Description

A DOUBLE ASSEMBLING STRUCTURE OF SLIDING

WINDOW FRAME ASSEMBLY FOR WINDOW CLOSING IN

THE SLIDING WINDOW SYSTEM

Technical Field

[1] The present invention relates to a window system (hereinafter, interchangeable with a door system) such as a horizontal sliding sash window/door for a building or a vehicle. More particularly, the present invention relates to a more stable and durable double coupling structure for a movable sash frame assembly in a horizontal sliding sash window system having a fixed sash (hereinafter, interchangeable with a fixed window or a fixed door) adapted to remain stationary and a movable sash (hereinafter, interchangeable with a movable window or a movable door) adapted to slide relative to the fixed sash to be opened/closed, the structure having double tilted guide grooves and double guide protrusions for connecting movable sash frames to a roller assembly and a rail guide assembly, respectively, so that, when the movable sash is opened/closed, the movable sash frames integrally compress the sealing member around the window frame in a perpendicular direction. Background Art

[2] A conventional horizontal sliding sash window system consists of sashes, which have a pane of glass installed therein, and a window frame, which is installed on the wall of a building to accommodate the sashes. More particularly, the window frame has rails for guiding the sliding movement of the movable sash. The movable sash has rail guides and rollers positioned on the upper and lower external portions thereof so that the movable sash can move smoothly along the rails of the window frame. The sashes have a pane of glass or other material installed therein, and are placed inside the window frame.

[3] However, such a conventional, simple structure makes it difficult to expect a high level of soundproofing, air tightness (windproofing), water tightness, heat resistance, wind pressure resistance, etc. in the entire window system. In an attempt to solve this problem, a sealing member, such as mohair or a windproof rubber gasket, may be attached between the window frame and the sashes. However, this type of sealing has its limitations. In addition, the sealing member is deformed or worn down as time elapses. This makes it difficult to maintain the same level of performance.

[4] In order to overcome the disadvantages of the above-mentioned conventional horizontal sliding sash window system, a lift & sliding type (in short, LS-type) opening/closing structure has been proposed. However, this structure has a problem in

that, when the sash is to be opened/closed, components related to rollers below the sash must lift/lower the heavy sash. The resulting concentration of load on the rollers is unfavorable in terms of dynamics. In addition, frequent lifting/lowering of the sash requires high-strength components having considerable durability. If the sash size increases above a predetermined threshold, it becomes difficult to properly bear the weight of the bulky sash frame and windowpane. This restricts the allowable range of the sash size.

[5] Furthermore, the sealing type (i.e. mechanism and direction of sealing) differs among the top, side, and bottom of the same sash. This means that, when the corners of the sash and the window frame having different sealing types contact each other, perfect sealing performance is hardly guaranteed. The sealing at the top of the sash relies on weak elastic force that compresses the top sealing member against the top guide. As a result, it is hard to expect perfect sealing. It is also difficult to block the heat transfer between the inside and outside of the window via the top guide.

[6] Another conventional structure of relevance is disclosed in Korean Patent

Publication No. 10-2004-0075123 laid-open on August 27, 2004 (Application No. 10-2003-0010568, Applicant: TAK, Dong-Ho). This publication discloses a sliding sash having guide pieces formed on its front and rear ends (shown in FIGs. 6-8 of the publication). The guide pieces of the front and rear ends are forced against corresponding guide rollers, which are respectively installed on the window frame and the fixed sash, in the final stage of closing the sliding sash. As a result, the siding sash is moved back (i.e. toward the window frame and the fixed sash) and is forced against a rubber buffer. When the sliding sash is closed in this manner, its guide pieces are fitted between the rollers and the rubber buffer at the end. The large friction force occurring in this case requires that the user exert much force to completely close the sliding sash. From another point of view, the large amount of force compressing the rubber buffer all around results in huge reaction force, against which a considerable amount of force must be exerted to open the sliding sash. At the final stage of closing the sliding sash, the sliding sash and the guide pieces slide further toward the window frame (i.e. in such a direction that the sliding sash is closed) while the rubber buffer contacts the guide pieces. The resulting sealing between the rubber buffer and the guide pieces applies transverse frictional pressure to the rubber buffer. This pressure degrades the durability of the rubber buffer and shortens its life. Besides, the technical construction and operating condition of the playing means related to the rollers of the sliding sash (shown in FIGs. 9-12 of the publication) have serious problems. The publication teaches that, when the sliding sash switches from an opened condition to a closed condition, the weight of the sliding sash is displaced toward the inside of the building by the tilted roller assembly and that the sliding sash can freely slide without any

contact or interference with the sealing means (rubber buffer) behind the sliding sash. However, when the user inside the building actually opens/closes the sliding sash, it is customary to grab the handle and push the sliding sash backward while applying force necessary to slide it in the transverse direction. In this case, the conventional structure disclosed in the above-referenced publication provides no means to actively control the gap between the rollers and rails. This means that, when the user pushes the sliding sash backward, the contact between the sliding sash and the sealing means inevitably creates friction. Furthermore, even if the bottom of the sliding sash leans toward the inside of the building, there occurs a vertical clearance between the top of the sliding sash and the window frame, because the top of the sliding sash conventionally has a groove larger than that of the bottom so that the sliding sash can be easily fitted to or removed from the window frame. This means that the same eccentricity of weight of the sliding sash resulting from the tilted roller assembly on the bottom of the sliding sash does not occur in the top of the sliding sash. As a result, the top of the sliding sash jolts back and forth in the forward/backward gap between the top guide of the window frame and the top of the sliding sash (the gap must have the same size as that at the bottom the sash), regardless of the tilting direction.

[7] In order to avoid the shortcomings of the above-mentioned conventional horizontal sliding sash window system, an arm rotation & sliding type opening/closing structure has been proposed. This system has a sash placed on an arm in a cantilever type. This makes it very difficult to analyze the load. More particularly, the size of the movable sash is limited, and components other than the arm (e.g. rollers, rails) also require sufficient strength and sophisticated treatment so that the cantilever support structure can bear the eccentric weight of the heavy sash. This is unfavorable to productivity and economy. It is conventional to install an arm only on the bottom of the sash in this arm-type rotation structure. This means that, unlike the bottom of the sash, the separately constructed top frame of the sash moves independently, i.e. its operation is not interlinked, until the sash is completely closed (if a strong wind blows while the sash is not completely closed, the resulting wind pressure jolts the top frame). This makes the user feel uneasy.

[8] In order to solve the above-mentioned structural problems of conventional window systems (e.g. horizontal sliding sash windows/doors), the inventors of the present application have proposed a novel window system as disclosed in PCT Application No. PCT/KR2006/005909 filed on March 15, 2007 prior to the present application. The proposed window system has a fixed sash adapted to remain stationary and a movable sash adapted to slide relative to the fixed sash to be opened/closed. The system has a simple opening/closing structure, i.e. the number of components constituting the window system is minimized, while ensuring the basic performance that the entire

window system is expected to exhibit, such as excellent soundproofing, air tightness (windproofing), water tightness, heat resistance, wind pressure resistance, stiffness for supporting a pane of glass or other material, etc. This reduces the sectional profile of the sash, on which components are installed, and improves the economy. As a result, a larger windowpane can be fitted to the same size of window frame. This increases the degree of lighting and openness. In addition, the horizontal sliding sash window system having such a structure (shown in FIGs. 1-9 of the accompanying drawings) requires a lower level of installation precision so that, when the system is assembled on the construction site, the possibility of erroneous installation can be lowered.

[9] The construction of the window system proposed in the above-referenced application, which precedes the present application, will now be described with reference to the drawings. Referring to FIGs. 1-3, top and bottom rails 1 Ia and 1 Ib are installed on the window frame 10 so that the movable sash 40 can slide along them. A rail guide assembly 41a, 42a is positioned above the top frame 40a of the movable sash 40. The rail guide 41a of the rail guide assembly 41a, 42a continuously engages with the top rail 1 Ia. A roller assembly 41b, 42b is positioned below the bottom frame 40b of the movable sash 40. The roller 41b of the roller assembly 41b, 42b continuously engages with the bottom rail 1 Ib. An opening/closing operation means (labeled 50 in FIG. 5) is installed on the lateral frame (labeled 40s in FIG. 5) of the movable sash 40 so that the top and bottom frames 40a and 40b of the movable sash 40 can be are separated from the roller assembly 41b, 42b below the bottom frame 40b and from the rail guide assembly 41a, 42b above the top frame 40a, respectively. After the separation, the top and bottom frames 40a and 40b can be moved in the forward/backward direction (labeled CL and OP in FIG. 1) together with a displacement component that is perpendicular to the direction of extension of the rails 11a and 1 Ib of the window frame 10. As a result, the same pressure acts on the sealing member 30 (made of an elastic material, for example) interposed between the window frame 10 or the fixed sash frame (labeled 20 in FIG. 7) and the frames of the movable sash 40 in a generally perpendicular direction.

[10] The detailed construction and operating principle regarding the movement of the frames of the movable sash 40 in a direction perpendicular to the direction of extension of the rails 1 Ia and 1 Ib will now be described with reference to FIGs. 2-4. FIG. 2 shows a condition before a sealed movement, and corresponds to (a) of FIG. 4. FIG. 3 shows a condition after a sealed movement, and corresponds to (b) of FIG. 4. The roller assembly 41b, 42b, which includes the underlying roller 41b, is pushed by movement force Fp including a component parallel to the direction of extension of the bottom rail 1 Ib. The movement force Fp is divided into two components of force Fh and Fv by the tilted connection structure between a tilted guide groove 43b, which

extends on the top plate 42b of the roller assembly 41b, 42b at an angle relative to the central axis of symmetry on the same plane, and a guide protrusion 44b protruding downward from the bottom surface of the bottom frame 40b of the movable sash 40. The vertical component of force Fv acting in a direction perpendicular to the direction of extension of the rails constrains the roller assembly 41b, 42b so that the underlying roller 41b is not displaced out of the bottom rail 1 Ib in the perpendicular direction. The resulting reaction force moves the bottom frame 40b of the movable sash 40 in the forward/backward direction, i.e. in the direction perpendicular to the direction of extension of the rails, as much as the width D of the tilted guide groove 43b. Use of such forward/backward movement constitutes the main principle of the proposed window system.

[11] FIGs. 5-7 show an exemplary opening/closing device embodying the above- mentioned operating principle. Particularly, the drawings show the action and effect of the window system when the rotation handle 4Oh of the opening/closing device 50 is rotated.

[12] When the window system is sealed by moving the frames of the movable sash 40 in the forward/backward direction together with a displacement component that is perpendicular to the direction of extension of the rails, the repulsive force from the window frame 10 and the sealing member 30 acts on the tilted guide grooves 43a and 43b and the guide protrusions 44a and 44b, which move in a staggering manner, because the underlying roller 41b and the overlying rail guide 41a are firmly fixed to the bottom plate 42a of the rail guide assembly and to the top plate 42b of the roller assembly, respectively, and because the guide protrusions 44a and 44b are firmly fixed to the top and bottom frames 40a and 40b of the movable sash 40, respectively. Such repulsive force causes distortion deformation of related components, particularly the bottom or top plate 42a or 42b having the tilted guide groove 43 a or 43b formed thereon. As a result, excessive separation displacement occurs between the frames of the movable sash 40 and the bottom plate 42a of the rail guide assembly 41a, 42a, as well as between the frames of the movable sash 40 and the top plate 42b of the roller assembly 41b, 42b. This raises concern that the frames of the movable sash 40 may be derailed. In order to prevent such derailment, the inventors have proposed that anti- separation plates 46a and 46b be additionally provided to prevent the bottom plate 42a of the rail guide assembly 41a, 42b and the top plate 42b of the roller assembly 41b, 42b from distorting, as shown in FIG. 8. More particularly, the anti-separation plates 46a and 46b are provided by forming steel bonding portions 48a and 48b on flanges extending above and below the frames of the movable sash 40, respectively, as shown in FIG. 9.

[13] However, the structure shown in FIGs. 8 and 9 has a problem in that the anti-

separation plates 46 and 46b are not easily installed, because it is not until seat-type sliding bearings 45a and 45b, the roller assembly 41b, 42b, and the rail guide assembly 41a, 42a are completely coupled to the frames 40a and 40b of the movable sash that the anti-separation plates 46a and 46b can be bonded to the frames 40a and 40b by the steel bonding portions 48a and 48b. Even after the installation, suppression of distortion deformation is limited to the area of contact between the tilted guide grooves 43a and 43b and the guide protrusions 44a and 44b. This means that the window system may become unstable due to possible overall distortion deformation of the bottom plate 42a of the rail guide assembly or the top plate 42b of the roller assembly. Furthermore, excessive concentration of load on the anti-separation plates 46a and 46b and the steel bonding portions 48a and 48b may deform the anti-separation plates 46a and 46b or even break the steel bonding portions 48a and 48b. Disclosure of Invention Technical Problem

[14] Therefore, the present invention has been made in view of the above-mentioned problems, and the present invention provides a double coupling structure for a movable sash frame assembly in a window system (e.g. horizontal sliding sash window/door) having a fixed sash adapted to remain stationary and a movable sash adapted to slide relative to the fixed sash to be opened/closed, the structure having a simple opening/ closing structure (i.e. the number of components constituting the window system is minimized) while ensuring the basic performance that the entire window system is expected to exhibit, including excellent soundproofing, air tightness (windproofing), water tightness, heat resistance, wind pressure resistance, and stiffness for supporting a pane of glass or other material, so that the sectional profile of the sash on which components are installed is reduced, the economy is improved, a larger windowpane can be fitted to the same size of window frame, and the degree of lighting and openness is improved, the structure ensuring that the window system can be easily assembled and installed on the construction site (i.e. the required level of installation precision is low) so that the possibility of erroneous installation can be decreased, and the structure providing stability high enough to prevent the movable sash from derailing from the window frame after installation, as well as sufficient durability.

[15] Also, the present invention provides a double coupling structure for a movable sash frame assembly in a window system having a fixed sash adapted to remain stationary and a movable sash adapted to slide relative to the fixed sash to be opened/closed, the structure guaranteeing not only that the movable sash can slide along rails installed on the window frame, but also that the movable sash can be separated from a rail guide and a roller positioned above and below the movable sash, respectively, and then

moved in the forward/backward direction toward the window frame or the fixed sash frame (i.e. in a direction perpendicular to the rails) at any location on the rails so that the sealing member, which is interposed between the window frame or the fixed sash frame and the entire movable sash frame, is compressed by even pressure in the perpendicular direction, and the structure structurally controlling deformation resulting from distortion stress acting on the rail guide assembly and the roller assembly, which are respectively installed on the top and bottom rails fixed to the window frame while being separated from the top and bottom of the movable sash frame, when the movable sash is opened/closed, so as to provide better structural stability.

[16] Meanwhile, the present applicant has filed another patent application on the same date as the present application, and it discloses a means for controlling deformation resulting from distortion stress acting on the bottom plate of the rail guide assembly and the top plate of the roller assembly. However, the present application aims at obtaining a more direct and stronger effect by guaranteeing that the tilted guide grooves and the guide protrusions undergo a tilted sliding action at a location as close as possible to the rail guide and the roller, which are directly coupled to the top and bottom rails, respectively, and which must remain coupled thereto even during opening/closing operations, instead of the bottom plate of the rail guide assembly and the top plate of the roller assembly. This structure reduces the moment resulting from the tilted sliding action of the titled grooves and the guide protrusions, and provides stiffness high enough to withstand it.

Technical Solution

[17] It is a principle technical objective of the present invention to provide a means for minimizing distortion deformation resulting from a rotational moment occurring in the rail guide assembly and the roller assembly of the horizontal sliding sash system proposed by the preceding invention when they undergo a tilted sliding movement under the action of the titled guide grooves and the guide protrusions and when their movement in a direction perpendicular to the direction of extension of the rails is limited due to the fact that they are fixed to the rails of the window frame. Unless such distortion deformation is suppressed, the rail guide and the roller may be derailed from the window frame. In other words, the present invention aims at providing a means for guaranteeing that, even if the rail guide assembly and the roller assembly slide at an angle relative to the movable sash frame, they undergo little distortion deformation in the direction perpendicular to the direction of extension of the rails. It is another principle technical objective of the present invention to provide a lubricating means for preventing concentrated friction force from occurring between the movable sash frame and the rail guide assembly and between the movable sash frame and the top plate of

the roller assembly, respectively, so that the movable sash frame can smoothly move back and forth. The lubricating means also lessens friction between the guide protrusions and the tilted guide grooves. It is still another principle technical objective of the present invention to provide such a structure without causing any inconvenience during assembly while guaranteeing sufficient durability.

[18] In accordance with an aspect of the present invention, there is provided a double coupling structure for a movable sash frame assembly in a horizontal sliding sash window system, the double coupling structure including a rail guide assembly and a roller assembly respectively positioned above and below frames of a movable sash so that the movable sash can slide along top and bottom rails fixedly installed on a window frame to be opened/closed, wherein double flange channel guides of predetermined length and height are integrally installed on a top and a bottom of the frames of the movable sash, respectively, the rail guide assembly connected to an opening/closing operation means and the roller assembly connected to the opening/ closing operation means are respectively inserted into space between first flanges and second flanges of the double flange channel guides while being able to slide so that the frames of the movable sash and the double flange channel guides can have a relative movement displacement on a plane in a tilted direction with regard to the rail guide assembly and the roller assembly, respectively, and both the first flanges and the second flanges of the double flange channel guides are provided with a structure for fitting guide protrusions into tilted guide grooves, the first flanges and the second flanges lying one above the other, so as to guide a sliding movement displacement of the rail guide assembly and the roller assembly in the tilted direction.

[19] Those skilled in the art can easily understand that terminology used herein, including a horizontal sliding sash window, a movable sash, and a fixed sash, is not limited to glass windows on buildings, but is applicable to all types of doors adapted to slide to be opened/closed (e.g. sliding opening/closing doors for vehicles).

Advantageous Effects

[20] The double coupling structure for a movable sash frame assembly in a horizontal sliding sash window system according to the present invention is advantageous in that the elastic sealing member interposed between the window frame and the movable sash is substantially completely and integrally compressed regardless of the location of the movable sash on rails installed on the window frame when the movable sash is opened/ closed. This improves soundproofing, air tightness, water tightness, heat resistance, and wind pressure resistance. In addition, the durability is improved by preventing the sealing member from being damaged. Respective members constituting the system receive lesser load than in the case of conventional systems. In other words, the system

according to the present invention is more structurally advantageous, durable, and easier to maintain. Furthermore, the fact that the members constituting the system can be easily assembled makes it easier to install the system on the spot. [21] In particular, the structure according to the present invention strictly suppresses distortion deformation that may occur in the roller assembly or the rail guide assembly.

This prevents the sash from derailing from the window frame after installation. As such, the window system structure has high operational stability and sufficient durability, and undergoes little friction between the guide protrusions and the tilted guide grooves. [22] Furthermore, the tilted guide grooves according to the present invention include a combination of sections having complex shapes so that the elastic reaction force occurring when the movable sash compresses the sealing member of the window frame while contacting it provides a locking action. This provides excellent soundproofing, air tightness (windproofing), water tightness, and heat resistance without a separate locking device.

Brief Description of the Drawings [23] The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which: [24] FIG. 1 shows the basic construction of a horizontal sliding sash window system according to a preceding invention, to which the present invention is applied; [25] FIGs. 2 and 3 are perspective views showing the operating principle of the horizontal sliding sash window system according to the preceding invention, together with sectional views magnifying the major portion; [26] FIG. 4 is a sectional view showing the operating condition of the horizontal sliding sash window system shown in FIGs. 2 and 3; [27] FIG. 5 shows an opening/closing operation means according to a first embodiment of the preceding invention, which is used in the window system to which the present invention is applied; [28] FIG. 6 shows the major construction and operating condition of the opening/ closing operation means shown in FIG. 5; [29] FIG. 7 shows the operating condition of an entire window system to which the opening/closing operation means according to the first embodiment of the preceding invention shown in FIG. 5 is applied;

[30] FIG. 8 shows an alternative embodiment of the preceding invention;

[31] FIG. 9 is a sectional view of the embodiment shown in FIG. 8;

[32] FIG. 10 shows a double coupling structure between a movable sash frame and a

rail guide assembly according to a first embodiment of the present invention; [33] FIG. 11 shows a double coupling structure between a movable sash frame and a roller assembly according to the first embodiment of the present invention; [34] FIG. 12 shows a combination of the first embodiment of the present invention and the opening/closing operation means according to the first embodiment of the preceding invention; [35] FIGs. 13 and 14 are sectional views showing the operating conditions of a window system as a combination of the first embodiment of the present invention and the opening/closing operation means according to the first embodiment of the preceding invention, when taken along line B-B shown in FIGs. 10 and 11; [36] FIGs. 15 and 16 are sectional views showing the operating conditions of a window system as a combination of the first embodiment of the present invention and the opening/closing operation means according to the first embodiment of the preceding invention, when taken along line A-A shown in FIGs. 10 and 11; [37] FIGs. 17 and 18 show combinations of the first embodiment of the present invention and alternative opening/closing operation means; [38] FIGs. 19 and 20 are top and bottom perspective views showing a double coupling structure between a movable sash frame and a roller assembly according to a second embodiment of the present invention, respectively; [39] FIGs. 21 and 22 are top and bottom perspective views showing a double coupling structure between a movable sash frame and a roller assembly according to a third embodiment of the present invention, respectively; [40] FIG. 23 shows a double coupling structure between movable sash frames and roller and rail guide assemblies, respectively, according to a fourth embodiment of the present invention; [41] FIG. 24 shows a double coupling structure between movable sash frames and roller and rail guide assemblies, respectively, according to a fifth embodiment of the present invention; [42] FIG. 25 is a sectional view showing the operating condition of a window system as a combination of the embodiment shown in FIG. 23 or 24 and the opening/closing operation means according to the first embodiment of the preceding invention; [43] FIG. 26 shows a double coupling structure between movable sash frames and roller and rail guide assemblies, respectively, according to a sixth embodiment of the present invention; [44] FIG. 27 shows a double coupling structure between movable sash frames and roller and rail guide assemblies, respectively, according to a seventh embodiment of the present invention; [45] FIG. 28 is a sectional view showing the operating condition of a window system as

a combination of the embodiment shown in FIG. 26 or 27 and the opening/closing operation means according to the first embodiment of the preceding invention;

[46] FIGs. 29 to 33 show tilted guide grooves having various shapes according to embodiments of the present invention;

[47] FIG. 34 shows exemplary installation of a rotary bearing member for supporting a guide protrusion on a rail guide assembly above a movable sash;

[48] FIG. 35 shows exemplary installation of a rotary bearing member for supporting a guide protrusion on a double flange channel guide;

[49] FIG. 36 shows exemplary use of a dual tube-type rotary bearing member according to the embodiment shown in FIG. 34;

[50] FIG. 37 shows exemplary use of a dual tube-type rotary bearing member according to the embodiment shown in FIG. 35;

[51] FIG. 38 is a sectional view of the dual tube-type rotary bearing member shown in

FIG. 37 when it has been coupled;

[52] FIG. 39 is an enlarged sectional view showing the installation condition of a dual tube-type rotary bearing member;

[53] FIG. 40 shows a contact surface between a rotary bearing member and a tilted guide groove according to a preferred embodiment of the present invention; and

[54] FIG. 41 shows a structure for connecting the bottom plates of rail guide assemblies or the top plates of roller assemblies to each other by a variable-length member according to the present invention. Mode for the Invention

[55] Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

[56] Referring to FIGs. 10-41, a double coupling structure for a movable sash frame assembly in a horizontal sliding sash window system according to the present invention includes an overlying rail guide assembly 4 IaI, 42a2, 42a and an underlying roller assembly 4 IbI, 41b2, 42b for enabling a movable sash 40 to slide along top and bottom rails 1 Ia and 1 Ib, which are fixedly installed on a window frame 10, to be opened/closed; movable sash frames 40a and 40b separately positioned below and above the rail guide assembly 41al, 41a2, 42a and the roller assembly 41bl, 41b2, 42b, respectively, so as to fix and support a pane of glass or other material; and tilted guide grooves and guide protrusions positioned between the movable sash frames 40a and 40b and the rail guide assembly 41al, 41a2, 42a and the roller assembly 41bl, 41b2, 42b, respectively, to connect them to each other. Furthermore, double flange channel guides 146a, 246a, 146b, and 246b of predetermined length and height are integrally installed on the top and bottom of the movable sash frames 40a and 40b, re-

spectively. The rail guide assembly 4 IaI, 41a2, 42a and the roller assembly 4 IbI, 41b2, 42b, which are connected to an opening/closing operation means, are inserted into the space between the first flanges 146al, 246al, 146b 1, and 246b 1 of the double flange channel guides 146a, 246a, 146b, and 246b and the space between the second flanges 146a2, 246a2, 146b2, 246b2 thereof, respectively, while being able to slide so that the movable sash frames 40a and 40b and the double flange channel guides 146a, 246a, 146b, and 246b can be displaced at an angle relative to the rail guide assembly and the roller assembly on a plane. Both the first flanges 146al, 246al, 146b 1, and 246b 1 and the second flanges 146a2, 246a2, 146b2, 246b2 are provided with a structure for fitting guide protrusions 44a and 44b into tilted guide grooves 43al, 43a2, 43b 1, and 43b2 so as to guide the tilted sliding displacement of the rail guide assembly and the roller assembly.

[57] Referring to FIGs. 10-18, a window system according to a first embodiment of the present invention includes a window frame 10; top and bottom rails 1 Ia and 1 Ib installed on the window frame 10; a movable sash 40 adapted to slide along the top and bottom rails 1 Ia and 1 Ib; a rail guide assembly 42a, 41al, 41a2 positioned above a top frame 40a of the movable sash 40, the rail guide 41a2 of the rail guide assembly 42a, 41a2, 41a2 continuously engaging with the top rail 1 Ia; a roller assembly 42b, 4 IbI, 41b2 positioned below a bottom frame 40b of the movable sash 40, the roller 41b2 of the roller assembly 42b, 41bl, 41b2 continuously engaging with the bottom rail 1 Ib; an opening/closing operation means (labeled 50 in FIGs. 13-16) installed on the lateral frame (labeled 40s in FIGs. 13-16) of the movable sash 40; and double flange channel guides 146a and 146b integrally formed on the top and bottom frames 40a and 40b of the movable sash 40, respectively. The opening/closing operation means is used to separate the double flange channel guides 146a and 146b from the rail guide assembly 42a, 4 IaI, 42a2 above the top frame 40a of the movable sash 40 and from the roller assembly 42b, 4 IbI, 41b2 below the bottom frame 40b of the movable sash 40, respectively, (i.e. separate the movable sash 40). After the separation, the double flange channel guides 146a and 146b are moved in the forward/backward direction (labeled CL and OP in FIG. 1) together with a displacement component that is perpendicular to the direction of extension of the rails 1 Ia and 1 Ib of the window frame 10. As a result, a sealing member 30 (made of an elastic material, for example) interposed between the window frame 10 or the fixed sash frame (labeled 20 in FIGs. 15 and 16) and the frames 40a and 40b of the movable sash 40 is compressed by the same pressure in a generally perpendicular direction. This type of organized combination of motions guarantees that the window system is sealed evenly and efficiently.

[58] Embodiments of the present invention will now be described in more detail with reference to the drawings.

[59] The top double flange channel guide 146a of the double flange channel guides

146a, 146b, 246a, and 246b according to the first embodiment of the present invention is related to the top structure of the movable sash, and will now be described with reference to FIG. 10. The top double flange channel guide 146a consists of first and second flanges 146al and 146a2, which have tilted guide grooves 43al and 43a2 formed thereon, respectively. The bottom plate 42a of the rail guide assembly is adapted to slide on the first flange 146al. A rail guide installation table 41al protrudes upward from the bottom plate 42a of the rail guide assembly, and has a transverse guide slot 141s of a predetermined length so that the second flange 146a2 is fitted into and slides along it. A rail guide 41a2 is placed above the rail guide installation table 41al. As such, the rail guide assembly 42a, 41al, 41a2 consists of the bottom plate 42a, the rail guide installation table 41al having the guide slot 141s, and the rail guide 41a2. A guide protrusion 44a is fitted into both tilted guide grooves 43al and 43a2 from above so as to extend through the transverse guide slot 141s of the rail guide installation table 4 IaI and the bottom plate 42a of the rail guide assembly and to protrude from both top and bottom (although the guide protrusion is shown in the drawing to be fitted from above, it may be fitted from below), so that the tilted sliding movement of the rail guide assembly 42a, 4 IaI, 41a2 is guided by the titled guide grooves 43al and 43a2 of the first and second flanges 146al and 146a2.

[60] The bottom structure of the movable sash according to the first embodiment of the present invention shown in FIG. 11 reflects the same constructional concept as the above-mentioned top structure. Particularly, the bottom double flange channel guide 146b consists of first and second flanges 146bl and 146b2, which have tilted guide grooves 43b 1 and 43b2 formed thereon, respectively. The top plate 42b of the roller assembly is adapted to slide beneath the first flange 146bl. A roller guide installation table 4 IbI protrudes downward from the top plate 42b of the roller assembly, and has a transverse guide slot 142s of a predetermined length so that the second flange 146b2 is fitted into and slides along it. A roller 41b2 is placed below the roller installation table 4 IbI. As such, the roller assembly 42b, 4 IbI, 41b2 consists of the top plate 42b, the roller installation table 41bl having the guide slot 142s, and the roller 41b2. A guide protrusion 44b is fitted into both tilted guide grooves 43b 1 and 43b2 from below so as to extend through the transverse guide slot 142s of the roller installation table 41bl and the top plate 42b of the roller assembly and to protrude from both top and bottom (although the guide protrusion is shown in the drawing to be fitted from below, it may be fitted from above), so that the tilted sliding movement of the roller assembly 42b, 4 IbI, 41b2 is guided by the titled guide grooves 43b 1 and 43b2 of the first and second flanges 146b 1 and 146b2.

[61] When a combination of the movable sash 40 incorporating the coupling structure

according to the first preferred embodiment of the present invention shown in FIGs. 10 and 11 and the opening/closing operation means 50 according to the first embodiment of the preceding invention shown in FIG. 12 is applied to a window system, it is opened/closed as shown in FIGs. 13-16. The opening/closing operation means 50 shown in FIG. 12 includes a rotation shaft member 50c extending on the lateral frame 40s of the movable sash 40 in the longitudinal direction and having a rotation handle 50h, and components for converting the rotational movement of the rotation shaft member 50c into a reciprocating movement. Particularly, the components include connecting rod members 52a and 52b linked with the bottom plate 42a of the rail guide assembly and the top plate 42b of the roller assembly, respectively, and rotation end members 51a and 51b coupled to the upper and lower ends of the rotation shaft member 50c, respectively, so that, when the rotation shaft member 50c rotates, the connecting rod members 52a and 52b push/pull the bottom plate 42a of the rail guide assembly and the top plate 42b of the roller assembly and ensure that they simultaneously move in the same direction as the top and bottom rails l la and 1 Ib together with a displacement component parallel to them. First ends of the rotation end members 51a and 51b are fixedly coupled to the upper and lower ends of the rotation shaft member 50c at the same location, respectively, and second ends thereof are linked with the connecting rod members 52a and 52b, respectively. The window system is operated as follows: when the rotation handle 50h is rotated, the rotation shaft member 50c and the rotation end members 51a and 51b, which are rigidly coupled to the upper and lower ends of the rotation shaft member 50c, respectively, rotate accordingly and push/pull the connecting rod members 52a and 52b, the bottom plate 42a of the rail guide assembly, and the top plate 42b of the roller assembly. The resulting action affects the coupling structure of the movable sash frame assembly according to the present invention.

[62] FIGs. 13 and 14 are sectional views taken along line B-B shown in FIGs. 10 and

11, and magnify portions of the window system during operation. FIGs. 15 and 16 are sectional views taken along line A-A shown in FIGs. 10 and 11, and magnify portions of the window system during operation. Particularly, FIGs. 13 and 14 respectively show conditions before and after an opening/closing operation by rotating the rotation handle 50h while the movable sash 40 abuts the window frame 10 (i.e. movement in a direction perpendicular to the direction of extension of the rails). FIGs. 15 and 16 respectively show conditions before and after an opening/closing operation by rotating the rotation handle 50h when the movable sash 40 is positioned halfway on the rails 1 Ia and 1 Ib of the window frame 10 (i.e. movement at an angle relative to the direction of extension of the rails). Such a difference in location of the movable sash 40, however, is not noticeable in the sectional views.

[63] As is clear from the enlarged sectional views of FIGs. 13-16, components ranging from the bottom plate 42a of the rail guide assembly to the rail guide installation table 4 IaI having the guide slot 141s, as well as components ranging from the top plate 42b of the roller assembly to the roller installation table 41bl having the guide slot 142s, are adapted to slide inside the double flange channel guides 146al, 146a2, 146bl, and 146b2 above and below the movable sash 40, respectively, while receiving force. This structure guarantees that, even if the double flange channel guides 146al and 146a2 (146a, as a whole, in FIG. 10) that are integral with the movable sash frame 40a slide at an angle and generate a moment while the rail guide 41a2 engages with the top rail 11a, the entire rail guide assembly 42a, 4 IaI, 41a2 between the first and second flanges 146al and 146a2 resists the moment and undergoes little distortion deformation, because both first and second flanges 146al and 146a2, which lie one above the other, are provided with a structure for fitting the guide protrusion 44a into the tilted guide grooves 43al and 43a2. The bottom of the movable sash has the same structure. That is, even if the double flange channel guides 146bl and 146b2 (146b, as a whole, in FIG. 11) that are integral with the movable sash frame 40b slide at an angle and generate a moment while the roller 41b2 engages with the bottom rail 1 Ib, the entire roller assembly 42b, 41bl, 41b2 between the first and second flanges 146bl and 146b2 resists the moment and undergoes little distortion deformation, because both first and second flanges 146bl and 146b2, which lie one above the other, are provided with a structure for fitting the guide protrusion 44b into the tilted guide grooves 43b 1 and 43b2. This prevents the movable sash frames from derailing and improves the operational stability. This also avoids concentration of stress in a specific part of the structure, e.g. the bottom plate of the rail guide assembly or the top plate of the roller assembly, which is otherwise damaged, and improves the durability.

[64] According to a preferred embodiment of the present invention, a seat-type lubricating means 45b is preferably installed at the interface between the top internal surface of the double flange channel guide 146b below the movable sash frame and the top plate 42b of the roller assembly in order to lower the frictional resistance. Such a lubricating means may be omitted if either the top internal surface of the double flange channel guide 146b or the top plate 42b of the roller assembly is made of a material having a self-lubricating function. In addition, the lubricating means, if necessary, is not limited to the seat type, and any equivalent may be adopted as long as it incorporates the same function.

[65] The seat-type sliding bearing 45b preferably includes a self-lubricating material

(e.g. Turcite) containing, as its main component, at least one compound selected from the group consisting of fluorocarbon complex, polyoxymethylene, nylon monomer, MC nylon, high molecular weight polyethylene, and Teflon. More preferably, the seat-

type sliding bearing 45b is made of a material capable of facilitating the sliding movement between the top internal surface of the double flange channel guide 146b and the top plate 42b of the roller assembly, as well as improving the durability and abrasion resistance of all components. Those skilled in the art can understand that the seat-type sliding bearing 45b must have a hole through which the guide protrusion 44b can extend. This means that, more generally speaking, the seat-type lubricating means can be installed not only at the entire interface undergoing a relative displacement, but also only on a part of the interface.

[66] More preferably, another seat-type lubricating means 45a is installed at the interface between the bottom internal surface of the double flange channel guide 146a above the movable sash frame and the bottom plate 42a of the rail guide assembly in order to lower the frictional resistance.

[67] FIGs. 17 and 18 show opening/closing operation means 150 and 250 as alternatives to the above-mentioned opening/closing operation means 50, when installed on a movable sash incorporating the coupling structure for a movable sash frame assembly according to the first embodiment of the present invention. The opening/closing operation means 150 and 250 have the same basic action and effect as the opening/ closing operation means 50. The sliding-type opening/closing operation means 150 shown in FIG. 17 includes a lateral sliding bar 150c extending on the lateral frame of the movable sash 40 in the longitudinal direction so as to move up and down; a rotation handle 150h for applying operation force necessary to move the lateral sliding bar 150c up and down; gear mechanisms 150L and 150P for converting the rotational movement of the rotation handle 150h into an upward/downward reciprocating movement of the lateral sliding bar 150c; flexible sliders 150S connected to the top and bottom of the lateral siding bar 150c so as to transmit the reciprocating movement to the top and bottom of the movable sash 40, respectively; top and bottom sliding bars 151a and 151b respectively installed on the top and bottom of the movable sash 40 in the horizontal direction so as to interwork with the flexible sliders 150S; and connecting rod members 152a and 152b for linking the top and bottom sliding bars 151a and 151b with the bottom plate 42a of the rail guide assembly and the top plate 42b of the roller assembly, respectively. Another type of opening/closing operation means 250 shown in FIG. 18 includes a rotation handle 25Oh installed on the lateral surface of the movable sash; a gear mechanism consisting of a lateral sliding bar 250C, a pinion 250P, and a rack 250L; and connecting rod members 252a and 252b connected to the top and bottom structures of the movable sash, respectively. These components are the same as those of the above-mentioned embodiment. However, the opening/closing operation means 250 shown in FIG. 18 has joint link members 251a and 251b positioned at the corners so as to transmit the upward/downward displacement occurring at the lateral

surface of the movable sash into a transverse displacement occurring at the top and bottom thereof after inverting the direction. In the case of the embodiments shown in FIG. 17 and 18, when the rotation handles 15Oh and 25Oh are operated, the horizontal displacement occurring at the bottom plate 42a of the rail guide assembly of the movable sash and the horizontal displacement occurring at the top plate 42b of the roller assembly have opposite directions, unlike the embodiment shown in FIG. 12. Therefore, the tilted guide grooves 43al, 43a2, 43b 1, and 43b2 respectively formed on the top and bottom have opposite directions, and the guide protrusions 44a and 44b respectively fitted to the tilted guide grooves 43al, 43a2, 43b 1, and 43b2 have opposite initial locations.

[68] Various opening/closing operation means other than those disclosed and shown in the specification and drawings of the present invention may be used in combination with the double coupling structure for a movable sash frame assembly according to the present invention, such as those disclosed and shown in the specification and drawings of the preceding application (PCT Application No. PCT/KR2006/005909).

[69] Regarding the bottom structure of the movable sash according to the present invention, FIG. 19 provides exploded and assembled perspective views showing, from above, a bottom double flange channel guide 246b according to a second embodiment of the present invention, and FIG. 20 provides exploded and assembled perspective views showing the same from below. The bottom double flange channel guide 246b consists of a first flange 246b 1 coupled to the top, particularly to the movable sash frame 4Oh, and second flanges 246b2L and 246b2R separately formed on opposite ends. The first and second flanges 246b 1, 246b2L, and 246b2R respectively have two tilted guide grooves 43b 1 and 43b2 formed thereon at a predetermined distance from each other. A roller assembly is adapted to slide at an angle in the space between the first and second flanges 246b 1, 246b2L, and 246b2R, and has a double-plate structure, i.e. top and bottom plates 42b and 42c. A portion of the bottom plate 42c is bent upward so that a roller installation table 4 IbI is installed on the bent portion together with a roller 41b2. The second flanges 246b2L and 246b2R of the bottom double flange channel guide 246b are formed on opposite ends with an opening between them so that the roller 41b2 of the roller installation table 4 IbI can be coupled to the bottom rail 1 Ib on the window frame. The top plate 42b of the roller assembly is adapted to slide beneath the first flange 246b 1, and the bottom plate 42c of the roller assembly is adapted to slide on the second flanges 246b2L and 246b2R. In addition, guide protrusions 44b are installed from below so that they protrude upward from the top plate 42b of the roller assembly and protrude downward from the bottom plate 42c of the roller assembly, in order to ensure that the tilted guide grooves 43b 1 and 43b2 formed on the first and second flanges 246b 1, 246b2L, and 246b2R guide the tilted

sliding movement of the top and bottom plates 42b and 42c of the roller assembly.

[70] More preferably, a stiffness reinforcement plate 42f is placed between the top and bottom plates 42b and 42c of the roller assembly for better structural stability.

[71] FIGs. 21 and 22 show a bottom structure of a movable sash according to a third embodiment of the present invention as an alternative to the second embodiment described with reference to FIGs. 19 and 20. The third embodiment has the same construction and operational effect as the second embodiment, except that two guide protrusions 44b are installed between the first and second flanges 246b 1, 246b2L, and 246b2R, which constitute the bottom double flange channel guide 246b, while being spaced a predetermined distance from each other, and that the top and bottom plates 42b and 42c of the roller assembly respectively have tilted guide grooves 43b 1 and 43b2 formed thereon so that the guide protrusions 44b guide the tilted sliding movement of the top and bottom plates 42b and 42c of the roller assembly.

[72] FIG. 23 shows, in its upper half, a top double flange channel guide 146a for a top structure of a movable sash according to a fourth embodiment of the present invention as an alternative to the embodiment described with reference to FIG. 10. The top double flange channel guide 146a consists of first and second flanges 146al and 146a2, which respectively have titled guide grooves 43al and 43a2 formed thereon. The bottom plate 42a of the rail guide assembly is adapted to slide on the first flange 146al. A rail guide installation table 41al protrudes upward from the bottom plate 42a of the rail guide assembly, and has two separate rail guides 41a2 formed on its top. The rail guide installation table 41al is adapted to slide beneath the second flange 146a2. Guide protrusions 44a are fitted into both tilted guide grooves 43al and 43a2, which lie one above the other, so as to extend through the bottom plate 42a and the rail guide installation table 4 IaI of the rail guide assembly and to protrude form both top and bottom, in order to ensure that the titled guide grooves 43 a 1 and 43 a2 guide the tilted sliding movement of the rail guide assembly 42a, 4 IaI, 42a2. The difference between the first and fourth embodiments lies in the fact that, instead of the guide slot 141s, two separate rail guides 41a2 are formed on the rail guide installation table 4 IaI so that a relative sliding action can occur on the top surface of the rail guide installation table 4 IaI and the bottom surface of the second flange 146a2 in the space defined between both rail guides 41a2.

[73] FIG. 23 also shows, in its lower half, a bottom double flange channel guide 146b for a bottom structure of a movable sash according to the fourth embodiment of the present invention as an alternative to the embodiment described with reference to FIG. 11. The bottom double flange channel guide 146b consists of first and second flanges 146bl and 146b2, which respectively have titled guide grooves 43b 1 and 43b2 formed thereon. The top plate 42b of the roller assembly is adapted to slide beneath the first

flange 146bl. A roller installation table 4 IbI protrudes downward from the top plate 42b of the roller assembly, and has two separate rollers 41b2 formed on its bottom. The roller installation table 41bl is adapted to slide on the second flange 146b2. Guide protrusions 44b are fitted into both tilted guide grooves 43b 1 and 43b2, which lie one above the other, so as to extend through the top plate 42b and the roller installation table 4 IbI of the roller assembly and to protrude form both top and bottom, in order to ensure that the titled guide grooves 43b 1 and 43b2 guide the tilted sliding movement of the roller assembly 42b, 4 IbI, 42b2. The difference between the first and fourth embodiments lies in the fact that, instead of the guide slot 142s, two separate rollers 41b2 are formed on the roller installation table 4 IbI so that a relative sliding action can occur on the bottom surface of the roller installation table 4 IbI and the top surface of the second flange 146b2 in the space defined between both rollers 41b2.

[74] Particularly, FIG. 23 shows the positional relationship between the double flange channel guides 146a and 146b and the rail guide and roller assemblies, as well as that of the guide protrusions 44a and 44b inside the tilted guide grooves 43al, 43a2, 43b 1, and 43b2, before and after a tilted sliding operation (shown in the left and right halves, respectively), in order to facilitate understanding of the circumstance involving such a relative sliding action.

[75] FIG. 24 shows an alternative movable sash frame assembly according to a fifth embodiment of the present invention. The top double flange channel guide 246a includes a first flange 246al and two separate second flanges 246a2L and 246a2R (or a second L- flange and a second R-flange). The first and second flanges 246al, 246a2L, and 246a2R respectively have tilted guide grooves 43al and 43a2 formed thereon. The bottom plate 42a of the rail guide assembly is adapted to slide on the first flange 246al. A rail guide installation table 41al protrudes upward from the bottom plate 42a of the rail guide assembly, and has a rail guide 41a2 formed at the center of its top. The rail guide installation table 4 IaI is adapted to slide beneath the second flanges 246a2L and 246a2R. The second flanges 246a2L and 246b2R are formed on opposite ends with an opening between them so that the rail guide 41a2 of the rail guide installation table 4 IaI can be coupled to the top rail 1 Ia on the window frame. Guide protrusions 44a are fitted to both tilted guide grooves 43al and 43a2, which lie one above the other, so as to extend through the bottom plate 42a and the rail guide installation table 4 IaI of the rail guide assembly and protrude from both top and bottom, in order to ensure that the tilted guide grooves 43al and 43a2 guide the tilted sliding movement of the rail guide assembly 42a, 4 IaI, and 41a2.

[76] FIG. 24 also shows the bottom structure of the movable sash. Particularly, the bottom double flange channel guide 246b includes a first flange 246b 1 and two separate second flanges 246b2L and 246b2R (or a second L-flange and a second R-

flange). The first and second flanges 246b 1, 246b2L, and 246b2R respectively have tilted guide grooves 43b 1 and 43b2 formed thereon. The top plate 42b of the roller assembly is adapted to slide beneath the first flange 246b 1. A roller installation table 4 IbI protrudes downward from the top plate 42b of the roller assembly, and has a roller 41b2 formed at the center of its bottom. The roller installation table 4 IbI is adapted to slide on the second flanges 246b2L and 246b2R. The second flanges 246b2L and 246b2R are formed on opposite ends with an opening between them so that the roller 41b2 of the roller installation table 4 IbI can be coupled to the bottom rail 1 Ib on the window frame. Guide protrusions 44b are fitted to both tilted guide grooves 43b 1 and 43b2, which lie one above the other, so as to extend through the top plate 42b and the roller installation table 4 IbI of the roller assembly and protrude from both top and bottom, in order to ensure that the tilted guide grooves 43b 1 and 43b2 guide the tilted sliding movement of the roller assembly 42b, 4 IbI, 41b2.

[77] FIG. 25 is a sectional view showing the operating condition of a window system when the fourth or fifth embodiment described with reference to FIG. 23 or 24 is applied to a movable sash opening/closing system shown in FIG. 12. The left half of FIG. 25 corresponds to an open condition in which the movable sash 40 is spaced from the sealing member 30 installed on the window frame 10. The right half of FIG. 25 corresponds to a condition in which the movable sash 40 makes contact with the sealing member 30 when a tilted sliding action has occurred between the tilted guide grooves 43al, 43a2, 43b 1, and 43b2 and the guide protrusions 44a and 44b and, consequently, the movable sash frames 40a and 40b and the double flange channel guides 246a (246al, 246a2L, and 246a24) and 246b (246b 1, 246b2L, and 246b2R), which are integral with them, have been separated from the rail guide and roller assemblies and displaced in a direction perpendicular to the rails l la and 1 Ib.

[78] FIG. 26 shows an alternative movable sash frame assembly according to a sixth embodiment of the present invention. Referring to the drawing, a guide protrusion 44a is installed between the first and second flanges 146al and 146a2 of the top double flange channel guide 146a. The bottom plate 42a of the rail guide assembly is adapted to slide on the first flange 146al. A rail guide installation table 41al protrudes upward from the bottom plate 42a of the rail guide assembly, and has two separate rail guides 41a2 formed on its top. The rail guide installation table 4 IaI is adapted to slide beneath the second flange 146a2. The bottom plate 42a and the rail guide installation table 4 IaI of the rail guide assembly 42a, 4 IaI, 41a2 respectively have tilted guide grooves 43al and 43a2 formed thereon so that the guide protrusion 44a is fitted to both tilted guide grooves 43al and 43a2, which lie one above the other, in order to ensure that the guide protrusion 44a guides the tilted sliding movement of the rail guide assembly 42a, 4 IaI, 41a2.

[79] FIG. 26 also shows the bottom structure of the movable sash. Particularly, a guide protrusion 44b is installed between the first and second flanges 146bl and 146b2 of the bottom double flange channel guide 146b. The top plate 42b the roller assembly is adapted to slide beneath the first flange 146bl. A roller installation table 41bl protrudes downward from the top plate 42b of the roller assembly, and has two separate rollers 41b2 formed on its bottom side by side. The roller installation table 41bl is adapted to slide on the second flange 146b2. The top plate 42b and the roller installation table 4 IbI of the roller assembly 42b, 4 IbI, 41b2 respectively have tilted guide grooves 43b 1 and 43b2 formed thereon so that the guide protrusion 44b is fitted to both tilted guide grooves 43b 1 and 43b2, which lie one above the other, in order to ensure that the guide protrusion 44b guides the tilted sliding movement of the roller assembly 42b, 4 IbI, 41b2.

[80] The difference between the sixth and fourth embodiments respectively shown in

FIGs. 26 and 23 lies in the fact that the positional relationship between the tilted guide grooves and the guide protrusions is the opposite.

[81] FIG. 27 shows a seventh embodiment of the present invention, which is the same as the fifth embodiment described with reference to FIG. 24, except that the installation location of the tilted guide grooves and the guide protrusions is the opposite. Particularly, the double flange channel guide 246a according to the seventh embodiment consists of a first flange 246al and second flanges 246a2L and 246a2R. Two guide protrusions 44a are placed at a predetermined distance from each other between the first and second flanges. The rail guide assembly includes a bottom plate 42a and a rail guide installation table 4 IaI protruding upward from the bottom plate 42a and having a rail guide 41a2 on its top. The second flanges 246a2L and 246aR2 are separately formed on opposite ends so that the rail guide 41a2 of the rail guide installation table 4 IaI can be coupled to the top rail 1 Ia on the window frame. The bottom plate 42a of the rail guide assembly is adapted to slide on the first flange 246al. The rail guide installation table 41al of the rail guide assembly is adapted to slide beneath the second flanges 246a2L and 246a2R. The bottom plate 42a and the rail guide installation table 4 IaI of the rail guide assembly respectively have tilted guide grooves 43al and 43a2 formed thereon so that the guide protrusions 44a guide the tilted sliding movement of the bottom plate 42a and the rail guide installation table 41al of the rail guide assembly.

[82] FIG. 27 also shows the bottom structure in its lower half. The bottom double flange channel guide 246b consists of a first flange 246b 1 and second flanges 246b2L and 246b2R. Two guide protrusions 44b are placed at a predetermined distance from each other between the first and second flanges. The roller assembly includes a top plate 42b and a roller installation table 4 IbI protruding downward from the top plate 42b

and having a roller 41b2 on its bottom. The second flanges 246b2L and 246b2R are separately formed on opposite ends so that the roller 41b2 of the roller installation table 4 IbI can be coupled to the bottom rail 1 Ib on the window frame. The top plate 42b of the roller assembly is adapted to slide beneath the first flange 246b 1. The roller installation table 4 IbI of the roller assembly is adapted to slide on the second flanges 246b2L and 246b2R. The top plate 42b and the roller installation table 4 IbI of the roller assembly respectively have tilted guide grooves 43b 1 and 43b2 formed thereon so that the guide protrusions 44b guide the tilted sliding movement of the top plate 42b and the roller installation table 4 IbI of the roller assembly.

[83] FIG. 28 is a sectional view showing the operating condition of the structure shown in FIGs. 26 and 27 in a similar manner as FIG. 25. It is clear from a comparison between FIGs. 28 and 25 that, although the positional relationship between the guide protrusions and the titled guide grooves is the opposite, there is little difference in the actual operating process or effect.

[84] Reference numeral 41b3 shown in FIGs. 10-28 designates a bottom rail guide. This component is not indispensable to the construction according to the above-mentioned embodiments of the present invention, but can be employed optionally. When adopted, the bottom rail guide 41b3 is installed on the bottom of the movable sash 40 so as to support both lateral surfaces of the bottom rail 1 Ib separately from the roller 41b2. This prevents the bottom of the movable frame from escaping from the bottom rail 1 Ib in a twofold manner.

[85] FIG. 29 shows the detailed shape of the tilted guide grooves 43al, 43a2, 43b 1, and

43b2 (hereinafter, simply 43a and 43b), which have been given as examples in FIGs. 10-28 to describe the present invention. Referring to FIG. 29, the tilted guide grooves 43 a and 43b have a combination of a central tilted section S extending at an angle relative to the direction of extension of the rails, and parallel linear sections Ll and L2 positioned on both sides of the tilted section S while extending in parallel with the direction of extension of the rails. More particularly, the parallel linear sections Ll and L2, which are parallel to the direction of extension of the top or bottom rail 1 Ia or 1 Ib, guarantee that, once the forward/backward sealed movement of the movable sash is completed, the movable sash does not jolt on the rails 11a and 1 Ib in the forward/ backward direction due to external force (e.g. elastic repulsive force from the sealing member or strong wind force), but remains at a fixed location as long as the rotation handle of the sealing operation means is not operated in the opposite direction (i.e. as long as no force is applied in parallel with the direction of extension of the rails). As such, the parallel linear sections Ll and L2 act as locking means.

[86] Although the tilted guide grooves shown in FIG. 29 have parallel linear sections on both sides of the tilted section, they may have a parallel linear section only on one side.

Alternatively, the tilted guide grooves shown in FIG. 30 have a first tilted section S 1 lying at the center while extending at an angle θ and a second tilted section S2 positioned on one side (e.g. left) of the first tilted section S 1 while extending at an angle θ that is opposite to the angle θ of the first tilted section Sl. The angle and length of the sections are preferably determined in such a manner that the range δ of movement enabled by the second tilted section S2 in a direction perpendicular to the direction of extension of the rails is smaller than the range δ of movement enabled by the first titled section Sl (i.e. in order to keep the sealing member fastened properly).

[87] FIG. 31 shows a tilted guide groove as an alternative to that shown in FIG. 29. The alternative tilted guide groove guarantees that the rotation handle 50h can be rotated further when the guide protrusions 44a and 44b move along the tilted guide grooves 43a and 43b and compress the sealing member 30 against the window frame to the greatest extent. Then, the movable sash can receive the elastic repulsive force from the sealing member 30 and move backward. In order to realize such an operating condition, a stopping groove G may be formed in the first parallel linear section Ll on one side of the central tilted section Ll as a space having a diameter d2 larger than the diameter dl of the guide protrusions 44a and 44b, as shown in FIG. 31. The depth of the stopping groove G is preferably determined in such a manner that the range δ of movement of the guide protrusions 44a and 44b in a direction perpendicular to the direction of extension of the rails, when they enter the stopping grooves G due to the elastic repulsive force from the sealing member 30, is smaller than the range δ of movement of the guide protrusions 44a and 44b in the central tilted section S (i.e. in order to keep the sealing member fastened properly).

[88] Tilted guide grooves having the shape shown in FIGs. 30 or 31 are advantageous in that, when the user rotates the rotation handle 50h to close the movable sash while forcing the top frame 40a (only the top frame appears in the top view) of the movable sash against the sealing member 30, the user can feel, via the rotation handle 50h, that the degree of compression decreases in the section of maximum compression of the sealing member 30. As such, the user can sense how much the movable sash has been closed.

[89] FIGs. 32 and 33 show tilted guide grooves 43a and 43b, which are slightly modified versions of those shown in FIGs. 30 and 31, respectively. The tilted guide grooves 43a and 43b have an additional stopping groove G at the end of a parallel linear section L or L2 to the right of the central tilted section Sl or S. Those skilled in the art can easily understand that various types of tilted guide grooves can be obtained by variously combining any of the above-mentioned shapes.

[90] Besides the shapes shown in FIGs. 29-33, the tilted guide grooves may have a simpler shape, e.g. a linear shape or the shape of a circular arc having a predetermined

curvature.

[91] When guide protrusions 44a according to the present invention are installed on a rail guide assembly as shown in (a) and (b) of FIG. 34, or when guide protrusions 44b according to the preset invention are installed on double flange channel guides 246b 1, 246b2L, and 246b2R as shown in FIG. 35, various types of rotary bearing members 47a are placed in respective installation holes so that the guide protrusions 44a are supported in the axial direction while being able to rotate. This prevents the guide protrusions 44a from generating friction when they slide along the tilted guide grooves of various above-mentioned shapes and collide with the lateral walls of the tilted guide grooves. Such a structure for preventing friction is not limited to the example shown in the drawing, and can be variously modified depending on specific applications.

[92] Those skilled in the art can easily understand that, although the rotary bearing members 47a are solely installed on the rail guide assembly above the movable sash to support the guide protrusions 44a according to the embodiment shown in (a) and (b) of FIG. 34, the roller assembly below the movable sash may also have rotary bearing members installed thereon to support the guide protrusions 44b. Furthermore, although the rotary bearing members 47a are interposed between the installation holes and the fixed ends of the guide protrusions 44a as shown in the left half of FIG. 35, the positional relationship may be modified as long as friction is reduced. For example, as shown in the right half of FIG. 35, the fixed ends (upper and lower ends shown in the drawing) of the guide protrusions 44b are fixedly installed in the installation holes, and the rotary bearing members 47b are placed on parts of the guide protrusions 44b, which make contact with the lateral surface of the tilted guide grooves 43b 1 and 43b2, so that the friction between the guide protrusions 44b and the titled guide grooves 43b 1 and 43b2 is reduced.

[93] The rotary bearing members 47a, 47b are not limited to the conventional cylindrical ball bearings shown in FIG. 34(a) and FIG. 35. Alternative rotary bearing members 47a and 47b shown in FIG. 34(b) and FIG. 39 have a dual-tube structure and, particularly, include cylindrical lubricating means 47al and 47b 1 made of a self- lubricating material and axially coupled to a portion (e.g. upper end) of the guide protrusions 44a and 44b which makes contact with the lateral surface of the tilted guide groove 43al, 43a2, 43b 1, and 43b2, and cylindrical rotary caps 47 a2 and 47b2 coupled to the outer peripheral surface of the lubricating means 47al and 47b 1 (after the dual tube is fitted, the upper end of the guide protrusions is compressed and deformed to fixedly couple it). Various examples of guide protrusions 44a and 44b having rotary bearing members 47a and 47b of such a dual-tube structure are shown in FIGs. 36-38.

[94] More particularly, the contact surfaces of the rotary bearing members 47a and 47b formed on the guide protrusions 44a and 44b and/or the tilted guide grooves 43a 1,

43a2, 43b 1, and 43b2 include convex surfaces as shown in (a) and (b) of FIG. 40. This reduces the contact surfaces as much as possible so that, when the tilted guide grooves 43al, 43a2, 43b 1, and 43b2 are at a high level, the guide protrusions 44a and 44b undergo minimized friction even if they are tilted.

[95] Meanwhile, the height δv of the space between the first and second flanges of the double flange channel guides according to the present invention, typically shown in FIG. 10, is preferably larger than a component δh of the tilted sliding displacement of the rail guide assembly, which is perpendicular to the direction of the rails, so that distortion deformation caused by the tilted sliding action of the rail guide assembly can be controlled more efficiently (the same description is applied to the roller assembly).

[96] Furthermore, although it has been assumed that, among the major components of the device for opening/closing the horizontal sliding sash window system according to the present invention, a single rail guide assembly 41al, 41a2, 42a and a single roller assembly 41bl, 41b2, 41b3, 42b are placed above and below each movable sash, respectively, more than one rail guide assemblies and roller assemblies may be used. In this case, it is convenient to connect a number of double flange channel guides 146a, 146b, 246a, and 246b, rail guide assemblies, and roller assemblies, which respectively have a predetermined length, to one another. Considering that the size (width) of the sashes is not the same, it is preferred to use intermediate connection members 49b, which have a number of connection holes, between the bottom plates of respective rail guide assemblies or between the top plates of respective roller assemblies as shown in FIG. 41 so that the distance between the connected plates can be adjusted. This is favorable to mass production and ease of assembly.

[97] In addition, although seat-type sliding bearings 45a and 45b have been provided as seat-type lubricating means in the above-mentioned embodiments of the present invention, they may be either omitted or replaced with equivalents (e.g. ball bearings) having similar functions, depending on the friction at the interface, which is determined by the load of the movable sash and the material, as mentioned above.

[98] Although several exemplary embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.