BACKGROUND OF THE INVENTION

[0001] The subject disclosure generally relates to elevator systems. More specifically, the subject disclosure relates to guide rails for elevator cars.

[0002] Elevator systems typically include an elevator car suspended in a hoistway by a number of suspension ropes. To guide the elevator car in the hoistway, a number of guide rails are arranged in the hoistway, for example, from the top to bottom of the hoistway. The elevator car is connected to the guide rails via one or more guide shoes such that the elevator car follows a path defined by the guide rails as it moves through the hoistway. Further, in some elevator systems, a braking mechanism connected to the elevator car acts on the guide rails to slow and/or stop the elevator car in the hoistway. The typical guide rail is a solid steel T-shaped rail. Such rail configurations are typically utilized because of their ability to withstand buckling and deflection during normal elevator operations and to withstand loads applied during emergency braking, or the use of safeties. An alternative to the typical solid rail is a rail formed from sheet metal.

[0003] Sheet metal rails are typically installed in sections along a length of the hoistway. During safety operation, the blades of the sheet metal rails often deflect or deform, especially at a joint between adjacent rail sections, necessitating the need for rail repair and/or replacement after operation of the safeties. Sheet metal rails have not been used with safeties, due to the problems described in this paragraph.

BRIEF DESCRIPTION OF THE INVENTION

[0004] According to one aspect of the invention, a guide rail for an elevator car includes a plurality of rail sections. Each rail section includes a base connectable with a wall of a hoistway and a blade connected to and extending from the base. The base and the blade are formed of one or more thicknesses of sheet metal material. The guide rail further includes a plurality of rail connectors. Each rail connector includes a first sleeve secured to a first base of a first rail section and a second sleeve secured to a second base of a second rail section and secured to the first sleeve. The plurality of rail connectors are configured to align the adjacent rail sections and improve guide rail strength at a joint between adjacent rail sections.

[0005] According to another aspect of the invention, an elevator system includes an elevator car disposed in a hoistway and a guide rail extending along the hoistway and operably connected to the elevator car for guiding the elevator car along the hoistway. The guide rail includes a plurality of rail sections, each rail section including a base connectable with a wall of the hoistway and a blade connected to and extending from the base. The base and the blade are formed of one or more thicknesses of sheet metal material. The guide rail further includes a plurality of rail connectors. Each rail connector includes a first sleeve secured to a first base of a first rail section and a second sleeve secured to a second base of a second rail section and secured to the first sleeve. The plurality of rail connectors are configured to align the adjacent rail sections and improve guide rail strength at a joint between adjacent rail sections.

[0006] According to yet another aspect of the invention, a guide rail for an elevator car includes a plurality of rail sections. Each rail section includes a base connectable with a wall of a hoistway and a blade connected to and extending from the base. The guide rail further includes a plurality of blade connectors, each blade connector extending from a first blade of a first rail section of the plurality of rail sections, to a second blade of a second rail section of the plurality of rail sections, adjacent to the first rail section. The plurality of blade connectors are configured to align the adjacent blades.

[0007] These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

[0009] FIG. 1 is a schematic of an embodiment of an elevator system;

[0010] FIG. 2 is a cross-sectional view of an embodiment of an elevator guide rail;

[0011] FIG. 3 is a plan view of an embodiment of a joint between elevator guide rail sections;

[0012] FIG. 4 is a cross-sectional view of an embodiment of a joint between elevator guide rail sections;

[0013] FIG. 5 is an exploded view of an embodiment of a joint between elevator guide rail sections;

[0014] FIG. 6 is a plan view of another embodiment of a joint between elevator guide rail sections; [0015] FIG. 7 is a cross-sectional view of another embodiment having a sleeve screwed to a guide rail section;

[0016] FIG. 8 is a cross-sectional view of an embodiment utilizing a T-shaped guide rail;

[0017] FIG. 9 illustrates an embodiment having a blade connector;

[0018] FIG. 10 illustrates another embodiment having a blade connector; and

[0019] FIG. 11 is a cross-sectional view of an embodiment having an internal alignment part.

[0020] The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.

DETAILED DESCRIPTION OF THE INVENTION

[0021] Shown in FIG. 1 is an embodiment of an elevator system 10. The elevator system 10 is located in a hoistway 12 and includes one or more guide rails 14 affixed to the hoistway 12. The guide rails 14 are connected to an elevator car 16 to guide the movement of the elevator car 16 through the hoistway 12. As shown in FIGS. 1 and 2, in some embodiments, the elevator car 16 includes at least one guide shoe 18 which interfaces with the guide rail 14.

[0022] As best shown in FIG. 1, the guide rail 14 includes a plurality of substantially identical guide rail sections 20. An embodiment of a guide rail section 20 is shown in FIG. 2. The cross-section is formed from a sheet metal, which may be bent, roll-formed, welded, and/or otherwise manipulated into the final shape. The guide rail section 20 includes a triangular- shaped base 22 which may be fixed to the hoistway 12, either directly or indirectly, and a blade 24 which extends outwardly from the base 22.

[0023] Referring now to FIG. 3, a sleeve 26 is located and secured at each end 28 of the rail section 20 to join adjacent rail sections 20. The sleeves 26 secured at adjacent rail sections 20 are secured to each other to provide a connection between adjacent rail sections 20 improving strength and alignment, and prevent movement and/or deformation of the rail sections 20 during use, for example, during safety engagement. The adjacent sleeves 26 may be secured to each other by any appropriate means, for example, welding or by threaded fasteners. In an exemplary embodiment, as shown in FIG. 3, each sleeve 26 has a sleeve flange 30 which abuts an adjacent sleeve flange 30, of the sleeve 26 secured to the adjacent rail section 20. The sleeve flanges 30 are provided with flange holes 32 through which fasteners such as bolts 34 may be installed to engage complimentary nuts 36 to secure the adjacent sleeves 26 together. In some embodiments, the bolt 34 or nut 36 may be permanently installed to the appropriate sleeve flange 30 by for example, welding, and its counterpart nut 36 or bolt 34 threaded into engagement when the sleeve flanges 30 are brought together. In some embodiments, the adjacent rail sections 20 are brought into contact with each other under a preload, and leaving a preload gap 64 between the sleeve flanges 30. Preloading the adjacent rail sections 20, ensures that joint stiffness in bending is provided by both a cross-sectional area of the rail sections 20 as well as the sleeves 26.

[0024] As shown, it may be desired to offset a sleeve joint 38 from a rail joint 40, such that the sleeve 26 secured at a first rail section 20 extends at least partially over a second rail section 20. This offset will further increase strength, stability and alignment of the rail joint 40.

[0025] Referring to FIG. 4, each sleeve 26 is wrapped at least partially around the base 22. To facilitate installation of the sleeve 26 onto the rail section 20, the sleeve 26 may be split into two sleeve halves 42, or more then two sleeve pieces. As shown in the illustrative embodiment, the sleeve halves 42 may include a sleeve half flange 44 at which the sleeve halves 42 are joined to each other by welding, threaded fasteners, or other suitable means.

[0026] Referring now to FIG. 5, each sleeve 26 or sleeve half 42 is secured to the rail section 20. In the exemplary embodiment shown, the sleeve 26 includes an array of sleeve tabs 46 protruding inwardly toward the rail section 20 and extending along a length of the rail section 20. In the embodiment of FIG. 5, one tab 46 is located at each sleeve side 48, but it is to be appreciated that other arrangements of tabs 46 may be utilized. For example, and as shown in FIG. 6, an array of four tabs 46 may be located at each sleeve side 48, and may be arranged substantially in a diamond- shaped pattern. Referring again to FIG. 5, the sleeve tabs 46 are engageable with complimentary rail slots 50 in each base side 52 of the rail section 20. In some embodiments, the rail slots 50 have a tapered width so that when the sleeves 26 are installed to the rail sections 20 and the adjacent rail sections 20 are secured to each other, the fit between the sleeve 26 and the rail section 20 tightens to secure the attachment therebetween. Even though the embodiment of FIG. 5 includes tabs 46 in the sleeve 26 engaging slots 50 in the rail sections 20, in other embodiments the configuration can be substantially reversed, with tabs 46 in the rail sections 20 engaging slots 50 in the sleeves 26. Further, as shown in FIG. 7, the sleeves 26 may be secured to the rail sections 20 by other means, for example screws 54 extending through the sleeves 26 and into the rail sections 20. Referring now to FIG. 8, this arrangement may be applied to rail shapes other than triangular. For example, as shown, the sleeves 26 may be configured to be secured to rail sections 20 having a t-shaped cross section.

[0027] Additionally, as shown in FIG. 9, some embodiments may include a blade connector 56 extending between adjacent blades 24 of adjacent rail sections 20. The blade connector 56 extends between the adjacent blades 24 to stabilize the blades 24 and improve blade 24 alignment between rail sections 20. In some embodiments, the blade connector 56 is a tongue 58 extending from a first blade 24 into a groove 60 formed in a second blade 24. In other embodiments, as shown in FIG. 10, the blade connector 56 is inserted in grooves 60 in adjacent blades 24. The blade connector 56 may be a separate piece of sheet metal that is secured in position by, for example, spot welding or countersunk fasteners (not shown) extending through the blade 24 and at least into the blade connector 56. The grooves 60 may be formed by removal of material from rail section 20 material (which material may then be used for the blade connector 56) prior to forming the material into a final rail section 20 shape.

[0028] Referring to FIG. 11, alignment of adjacent rail sections 20 can be further improved by utilizing an internal alignment part, which can take the form of a tube 62 inserted into the base 22 and fastened thereto by screws 54, as shown, or by other compatible fastening means. In some embodiments, the tube 62 is configured to abut the rail sections 20 at least partially around a perimeter of the tube 62. The tube 62 enhances lateral on vertical stiffness of the rail joint 40 between the tube sections 20, and also improves strength of the joint 40 and alignment between the adjacent rail sections 20.

[0029] While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.