Background Art As well known to those skilled in the art, in conventional toilets, a toilet seat is hingably mounted to a toilet bowl. Thus, a male user needs to manually elevate the toilet seat above the toilet bowl.

In order to solve this problem, several modifications to the conventional toilet have been introduced. For example, a spring is installed on the connection portion between the toilet bowl and the toilet seat. Thereby, the toilet seat comes to always stand upright by elastic force of the spring. However, this modification generates another problem. That is, in order to use the toilet in a seated position, the user presses the toilet seat by hand to lower the toilet seat on the toilet bowl.

Alternatively, the user steps on a pedal, thereby applying hydraulic pressure on a hose or a bellows and expanding the hose or the bellows. Then, the toilet seat is raised and erects upright by the expanding hose or bellows.

However, in order to erect the toilet seat using this modification, the user must keep his foot on the pedal, thereby causing another inconvenience.

Disclosure of the Invention Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide an apparatus for automatically opening and closing a toilet seat, in which seat erecting means is installed on one end of a rotary axis (hinge) of a toilet seat and seat lowering means is installed on the other end of the rotary axis. The seat lowering means is driven by the hydraulic pressure.

In accordance with the present invention, the above and other objects can be accomplished by the provision of an apparatus for automatically opening and closing a toilet seat included in a toilet including a toilet bowl, the toilet seat hingably mounted to the toilet bowl so as to uprightly erect or to be seated on the toilet bowl by an axial rotation of a hinge, and a washing device for washing the interior of the toilet bowl.

The apparatus for automatically opening and closing the toilet seat of the present invention further comprises seat lowering means (A), seat erecting means (B), and stopping means (C).

The seat lowering means (A) uses the hydraulic pressure of the washing device of the toilet. The hydraulic pressure contracts and expands a corrugated tube with an approximately semi-circular cross section within a designated angle, and the reciprocating movement of this corrugated tube is imposed to the hinge connecting the seat to the bowl, thereby lowering the seat.

The aforementioned seat lowering means (A) includes (A1) a cylindrical hinge housing having a fixing plate on one side of its inner surface and a stopping plate on an

opposite side; (A2) a rotating hinge extension axis coupled with one end of the hinge, which is a rotary axis of the seat, and having a protrusion formed in a longitudinal direction; and (A3) a water bag formed in a corrugated tube with an approximately semi-circular cross section and having one long side placed on the fixing plate of the hinge housing and the other long side placed on the protrusion, the water bag expanding by the hydraulic pressure of water supplied from the washing device and contacting the fixing plate.

The seat erecting means (B) serves to uprightly erect the seat, which is placed on the bowl by the seat lowering means (A), perpendicular to the bowl. The seat erecting means (B) always applies turning moment (torsion elastic force of the spring) on the hinge coupled with the seat toward the direction of a water tank of the washing device.

This turning moment applied on the hinge is controlled by the stopping means. The stopping means applies the turning moment by operating the washing device after using the toilet, thereby uprightly erecting the seat.

The aforementioned seat erecting means includes (B1) a rotary drum coupled with the other end of the hinge and having a recess on its outer surface; (B2) a drum housing fixed to the bowl and having an insertion hole on its outer surface, the drum housing having an inner diameter larger than an outer diameter of the rotary drum so that the drum housing surrounds the rotary drum; and (B3) a spring having one end inserted into one edge of the rotary drum so as to provide turning moment to the rotary drum and the other end fixed to a housing cap fixed to the drum housing.

The stopping means (C) of the apparatus passes through the insertion hole of the drum housing, and is inserted into

or separated from the recess of the rotary drum, thereby controlling the rotation of the hinge connected to the rotary drum.

Preferably, the stopping means may comprise a cylindrical housing including a through hole on its one end and a spring-receiving threshold on the inner wall of the through hole; a coil spring to be placed on the spring- receiving threshold; a T-type pin passing through the spring; and a bellows connected to the T-type pin and having a volume smaller than that of the water bag, the bellows contracting and expanding according to the hydraulic pressure of water supplied from the washing device. The T- type pin moves forward or backward via the through hole, and is inserted into or separated from the recesses of the rotary drum according to the contraction or the expansion of the bellows.

Further, preferably, the stopping means may comprise a cylindrical housing including a through hole on its one end and a threshold on the inner wall of the through hole; a T- type pin passing through the through hole; a spring connected to the T-type pin; a wire connected to the T-type pin; and wire pulling means for pulling the wire in a direction away from the through hole. The T-type pin moves forward or backward via the through hole by operation of the wire pulling means, and is thereby inserted into or separated from the recesses of the rotary drum.

Brief Description of the Drawings The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in

conjunction with the accompanying drawings, in which: Fig. 1 is a front view of a cistern tank type toilet using an apparatus for automatically opening and closing a toilet seat in accordance with the present invention; Fig. 2 is a front view of a compression tank type toilet using the apparatus for automatically opening and closing a toilet seat in accordance with the present invention; Fig. 3a is an enlarged view of seat lowering means (A) of Fig. 1; Fig. 3b is an exploded view of the seat lowering means (A) of Fig. 3a; Fig. 3c is a cross-sectional view showing an operation of the seat lowering means (A) of Fig. 3a; Fig. 4a is an enlarged view of seat erecting means (B) of Fig. 1; Fig. 4b is an exploded view of the seat erecting means (B) of Fig. 4a; Fig. 5a is an exploded view of stopping means (C); Fig. 5b is a cross-sectional view of the stopping means (C) of Fig. 5a; Fig. 6a is a cross-sectional view of modified stopping means (C); and Fig. 6b is an exploded view of the stopping means (C) of Fig. 6a coupled with the seat erecting means (B) of Fig.

4a.

Best Mode for Carrying Out the Invention Hereinafter, preferred embodiments of the present invention are described with reference to accompanying drawings.

Fig. 1 is a front view of a cistern tank type toilet using an apparatus for automatically opening and closing a toilet seat in accordance with the present invention, and Fig. 2 is a front view of a compression tank type toilet using the apparatus for automatically opening and closing a toilet seat in accordance with the present invention. Fig.

3a is an enlarged view of seat lowering means (A) of Fig. 1, and Fig. 3b is an exploded view of the seat lowering means (A) of Fig. 3a. Fig. 3c is a cross-sectional view showing an operation of the seat lowering means (A) of Fig. 3a.

Fig. 4a is an enlarged view of seat erecting means (B) of Fig. 1, and Fig. 4b is an exploded view of the seat erecting means (B) of Fig. 4a. Fig. 5a is an exploded view of stopping means (C), and Fig. 5b is a cross-sectional view of the stopping means (C) of Fig. 5a. Fig. 6a is a cross- sectional view of modified stopping means (C), and Fig. 6b is an exploded view of the stopping means (C) of Fig. 6a coupled with the seat erecting means (B) of Fig. 4a.

Generally, washing devices of the toilet are divided into two types, i. e., a cistern tank type and a compression tank type.

Figs. 1 and 2 show these two types of the toilets, respectively.

That is, Fig. 1 shows a cistern tank type toilet using the apparatus of the present invention, and Fig. 2 shows a compression tank type toilet using the apparatus of the present invention.

As shown in Fig. 1, a general hinge 13 (also, referred to as a hinge axis) for coupling a seat 3 with a bowl 1 extends in both directions. Thereby, seat lowering means 31 (A) is installed on the left of the hinge 13 and seat erecting means 51 (B) is installed on the right of the hinge

13. Of course, the installation positions of the seat lowering means 31 (A) and the seat erecting means 51 (B) are not limited thereto.

Figs. 3a to 3c show the seat lowering means 31 (A). As shown in Fig. 3a, the seat lowering means 31 (A) is fixed to the bowl 1 by a clamping bolt 43 and a nut 45.

As shown in Figs. 3a to 3c, the seat lowering means 31 (A) comprises a cylindrical hinge housing 33, a hinge extension axis 38, and a water bag 35. The hinge housing 33 includes a fixing plate 48 formed on a side of its inner wall and a stopping plate 47 formed on an opposite side of its inner wall. The hinge extension axis 38 is coupled with one end of the hinge 13, which is a rotary axis of the seat 3, and the other end of the hinge extension axis 38 is coupled with a bearing 39. A protrusion 37 is formed on the hinge extension axis 38 in a longitudinal direction. The water bag 35 is a corrugated tube with a semi-circular cross section. One longitudinal side of the water bag 35 is received by the fixing plate 48 of the hinge housing 33, and the other longitudinal side of the water bag 35 is received by the protrusion 37. The water bag 35 expands by a hydraulic pressure of water supplied from a water-supply pipe 11 of the washing device of the toilet so that one side of the water bag 35 contacts the stopping plate 47. Herein, reference number 41 denotes a lid, and reference number 6 denotes an interconnection pipe for connecting the water bag 35 to the water-supply pipe 11 for supplying water to a cistern tank (7 of Fig. 1) or a compression tank (7'of Fig.

2).

Fig. 3c is a cross-sectional view showing a process of contracting and expanding the water bag 35. The water bag 35 has a bellows form with corrugation or an expandable bag

form, thereby changing the size of the water bag 35 according to the volume of water within the water bag 35.

That is, when water is supplied to the cistern tank 7 or the compression tank (7'Fig. 2) by a nipple 15, the water flows into the water bag 35 or out of the water bag 35 according to the hydraulic pressure of the water-supply pipe 11, thereby changing the volume of the water bag 35 and rotating the protrusion (rotary plate) 37.

The apparatus of the present invention uses the contraction and expansion of the water bag 35 as a rotary force of the hinge 13, and its principle is described as follows.

The stopping plate 47 is formed within the housing 33 so that the rotary plate 37 stops at a point of approximately 100 degrees into the expansion direction of the water bag 35. The stopping plate 47 allows the rotary plate 37 to circularly reciprocate within a designated range. When water flows into the contracted water bag 35, the water bag 35 expands by the hydraulic pressure of the water. The expanding water bag 35 pushes the rotary plate 37. The rotary plate 37 is rotated by the pushing force of the water bag 35 until the rotation of the rotary plate 37 is blocked by the stopping plate 47. Since the rotary plate 37 is formed on the hinge extension axis 38, the hinge 13 fixed to the hinge extension axis 38 rotates, thereby lowering the toilet seat 3 toward the toilet bowl 1.

Figs. 4a and 4b show the seat erecting means 51 (B).

As shown in Fig. 4a, the seat erecting mean 51 (B) is fixed to the bowl 1 by a clamping bolt 63 and a nut 65.

As shown in Figs. 4a and 4b, the seat erecting means 51 (B) comprises a rotary drum 55, a drum housing 53, and a spring. The rotary drum 55 is coupled with one end of the

hinge 13 and includes a recess 55a on its outer surface.

The drum housing 53 is fixed to the bowl 1 and includes an insertion hole 53a. The drum housing 53 has an inner diameter larger than an outer diameter of the rotary drum 55 so that the drum housing 53 surrounds the rotary drum 55.

One end of the spring 61 is inserted into one edge of the rotary drum 55, thereby providing turning moment to the rotary drum 55, and the other end of the spring 61 is fixed to a housing cap 57 fixed to the drum housing 53.

Herein, reference number 59 is a spring holder. One end of the spring 61 is inserted into one edge of the rotary drum 55, and the other end of the spring 61 is inserted into the spring holder 59, thereby providing a torsion elastic force necessary to uprightly erect the seat to the hinge 13.

Elastic energy is stored in the spring 61 and the toilet seat 3 maintains its upright position by the elastic energy stored on the spring 61. When the toilet seat 3 is to be lowered, the elastic force of the spring 61 is made to be smaller than the rotary force of the rotary plate 37 rotating by the hydraulic pressure of the water-supply pipe 11. Thereby, a torsion force for lowering the toilet seat 3 adjacent to the toilet bowl 1 is applied on the hinge 13 at a normal time, and when the hydraulic pressure of the water- supply pipe 11 is removed by pressing a washing lever 9,9' of the seat 3, the torsion elastic force of the spring 61 becomes greater than the rotary force of the rotary plate 37, thereby applying a torsion force for erecting the toilet seat 3 on the hinge 13.

Reference number 71 represents stopping means. The stopping means 71 passes through the insertion hole 53a of the drum housing 53 and is inserted into or separated from the recess 55a of the rotary drum 55. Thereby, the stopping

means 71 serves to control the rotation of the rotary drum 55.

Figs. 5a and 5b show the stopping means 71. As shown in Figs. 5a and 5b, the stopping means 71 comprises a cylindrical housing 73, a coil spring 75, a T-type pin 77, and a bellows 79. The housing 73 includes a through hole on its one end and a spring threshold 76 on the inner wall of the through hole. The spring 75 is received by the spring threshold 76. The T-type pin 77 passes through the spring 75 and coupled with the housing 73. The bellows 79 is connected to the T-type pin 77 and has a volume smaller than that of the water bag 35. The bellows 79 contracts and expands according to the hydraulic pressure of water supplied from the washing device. Further, the bellows 79 also contracts and expands according to the hydraulic pressure of water supplied from the water-supply pipe (11 of Fig. 1), the nipple 15 and the interconnection pipe 6.

Thereby, the T-type pin 77 moves forward or backward via the through hole, and is inserted into or separated from the recess 55a of the rotary drum 55.

As shown in Fig. 5b, the inner wall of the cylindrical housing 73 is stepped. That is, an inner diameter of each level is different from other level. The T-type pin 77 passes through the through hole with the smallest inner diameter. The spring 75 surrounding the T-type pin 77 is received by the spring threshold 76.

The T-type pin 77 has a conical tip with a gentle slope. The T-type pin 77 moves forward by the hydraulic pressure and is inserted into the recess 55a of the rotary drum 55. Since not the whole body of the T-type pin 77 but the coned tip of the T-type pin 77 is inserted into the recess 55a, the T-type pin 77 moves backward by external

force larger than the force for inserting the T-type pin 77 into the recess 55a. Therefore, when a user softly pulls the toilet seat so as to use the toilet, the T-type pin 77 is separated from the recess, 55a. Then, the hinge 13 rotates, and the seat 3 lowers and rests on the bowl 1.

With reference to Figs. 1 to 5, the operation of the apparatus of the present invention is described in more detail hereinafter.

Before the user uses the toilet-the cistern tank 7 or the compression tank 7'are filled with water-the water bag 35 is in an expanded state by a designated hydraulic pressure of the water-supply pipe 11. Therefore, rotary force (+X), which is perpendicular to the axis of the hinge 13 and rotates in a reader's direction, is constantly applied on the left of the hinge 13.

Meanwhile, a torsion force (-X) of the spring 61, which is perpendicular to the axis of the hinge 13 and rotates in the paper's direction, is applied on the right of the hinge 13 provided with the seat erecting means 51. The torsion force (-X) of the spring 61, which rotates in the paper's direction, is designated to be smaller than the rotary force (+X), which rotates in the opposite direction by the expansion of the water bag 35.

Therefore, the seat 3 is lowered to rest on the bowl 1. However, since the bellows 79 of the stopping means 71 is also connected to the same water-supply pipe 11 and has a volume smaller than that of the water bag 35, the bellows 79 expands first, thereby inserting the T-type pin 77 into the recess 55a. Thus, the seat 3 maintains its upright position as long as any external force is not applied.

In order to use the toilet, when the user softly pulls the seat 3, the T-type pin 77 is separated from the recess

55a, thereby disengaging the rotary drum 55 from the T-type pin 77. Then, the hinge 13 rotates by the seat lowering means 31 and the seat 3 is lowered to rest on the bowl 1.

Herein, the T-type pin 77 separated from the recess 55a of the rotary drum 55 comes in contact with the outer surface of the rotary drum 55.

The lowered seat 3 is smoothly placed on the bowl 3 and the rotary plate 37 of the seat lowering means 31 is stopped by the stopping plate 47, thereby preventing immoderate force from being applied to the hinge 13.

After using the toilet, when the user operates the washing lever 9, the water level of the tank 7 becomes low.

Then, in order to fill up the tank 7, the valve operates and the hydraulic pressure of the water-supply pipe 11 becomes low.

When the hydraulic pressure of the water-supply pipe 11 becomes low, the water bag 35 and the bellows 79 contract. When the water bag 35 contracts, the force pushing the rotary plate 37 is eliminated, thereby eliminating the rotary force for rotating the hinge 13.

Since the bellows 79 also contracts, the T-type pin 77 moves backward by the restoring force of the spring (61 of Fig.

4b) and is separated from the recess 55a.

However, since the spring 61 of the seat erecting means 51 always applies its torsion force to the hinge 13, the activated torsion force is imposed on the rotary drum 55 and the hinge 13 the moment the T-type pin 77 is separated from the recess 55a, thereby uprightly erecting the seat 3.

Therefore, when the user presses the washing lever 9, the waste flows out of the bowl 1 and the seat 3 automatically stands.

That is, when the washing lever 9 is pressed, the

water in the tank 7 flows out and the tank 7 is again filled with water through the water-supply pipe 11. During filling of the tank 7 with water, the water bag 35 and the bellows 79 are not affected by the hydraulic pressure. However, after the tank 7 is filled with water and the valve of the tank 7 is closed, water is supplied to the water bag 35 and the bellows 79 via the water-supply pipe 11, thereby expanding the water bag 35 and the bellows 79. Since the bellows 79 has a volume smaller than that of the water bag 35, the bellows 79 expands prior to the water bag 35. When the bellows 79 expands, the T-type pin 77 moves forward by the hydraulic pressure and is inserted into the recess 55a of the rotary drum 55, thereby engaging the rotary drum 55 to the T-type pin 77. As the water bag 35 gradually expands and pushes the rotary plate 37, the hinge 13 and the seat 3 fixed to the hinge 13 are lowered. However, since the rotation of the hinge 13 is restricted by the T-type pin 77, the upright position of the seat 3 is maintained.

When a male user uses the toilet, that is, in case that the toilet is used while the position of the toilet seat 3 is upright, since the rotation of the seat 3 is restricted by the T-type pin 77, and the hydraulic pressure is removed simultaneously from the water bag 35 and the bellows 79 and then applied again, the upright position of the seat 3 is maintained.

Fig. 6b shows another embodiment of the present invention and illustrates modified stopping means 71. The stopping means 71 is operated by connecting a cable 93 to the T-type pin 77 and by pulling the cable 93. In this case, even if not shown in the drawings, cable pulling means 93 may be preferably used. The cable pulling means 93 may be operated by a switch (not shown), which is installed on a

back wall or a sidewall of the toilet.

Hereinafter, this embodiment of the present invention is described with reference to Figs. 6a and 6b.

When the user pushes the switch (not shown) so as to use the toilet, a wire 83 pulls the T-type pin 77, and the T-type pin 77 moves backward and is separated from the recess 55a of the rotary drum 55. Then, the rotary drum 55 is able to rotate within the drum housing 53. Thereby, the hinge 13 is also able to rotate and, as described above, the seat 3 lowers by the seat lowering means 31 and is placed on the bowl 1.

In this case, after using the toilet, when the user presses the washing lever 9, as described above, the seat 3 is automatically erected.

Industrial Applicability As apparent from the above description, the apparatus of the present invention automatically closes the toilet seat using hydraulic pressure and opens the toilet seat by the torsion spring, thereby relieving the users of the inconvenience of lifting up the toilet seat after or before using the toilet.

After using the toilet, the apparatus of the present invention always maintains the toilet seat in the upright position, thereby keeping the toilet clean and saving the trouble of cleaning the toilet.

Further, the toilet seat does not lower suddenly but is maintained in the upright position, thereby eliminating the problems of breakage of the toilet bowl and the toilet seat, and preventing old or feeble persons from being startled at noise generated by colliding the toilet seat

with the toilet bowl.

Although the preferred embodiments of the present invention have been disclosed 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.