TECHNICAL FIELD The present invention relates to apparatus for closing toilet seats and, in particular, to a novel automatic closure mechanism for controUably closing a toilet seat while permitting the seat to be forcibly urged to a lowered position without damaging the seat or the closure mechanism.

BACKGROUND ART

Toilet seats are a common cause of irritation in households where men and women share a bathroom equipped with a toilet fixture. Men must raise the toilet seat in order to use the toilet for urination. Women, however, use the toilet seat in its lowered position. Women are, therefore, often frustrated by finding the toilet seat in a raised position. This experience can be particularly frustrating and potentially hazardous when someone attempts to use the toilet in a sitting position in a dark or poorly lit room.

Considerable inventive ingenuity has been directed towards the development of apparatus for either closing toilet seats automatically and/or damping the descent of a toilet seat so that it closes without noise or damage to the seat or the toilet bowl.

Much of the prior art relates to bulky apparatus which clutters the toilet area with cylinders, electrical wires, hoses or other paraphernalia used to control the opening and/or closing of the seat or lid. Such paraphernalia is not only unattractive and difficult to clean, it can also represent a hazard which can potentially cause accidental tripping and the like.

More aesthetic and compact mechanisms for damping the closure of a toilet seat or automatically closing and damping the closure of a toilet seat have also been invented. One such mechanism is described in United States Patent 5,153,946 which issued October 13, 1992 to Yoke et al. This patent is entitled

APPARATUS AND METHOD FOR AUTOMATICALLY CLOSING A TOILET BOWL LID AND SEAT and describes an apparatus that includes a control mechanism

engageable with a toilet bowl lid for locking the lid in the open position after the lid is pivoted to the open position, and a timer mechanism for actuating the control mechanism to release the lid from the open position after a predetemined time interval. The timer mechanism is suspended while at least a predetermined weight is applied to the seat in a lowered position. The apparatus further includes a damper mechanism to retard the descent of the lid after the lid is urged to the closed position by the action of a coil spring when the predetemined time interval has expired.

United States Patent No. 5,193,228 which issued March 16, 1993 to Murasawa et al is entitled TOILET COVERING HINGE ASSEMBLY WITH

DAMPING CAPABILITY. This patent describes a hinge assembly for a toilet cover designed to dampen the motion of a toilet cover when it is moved from a raised to a lowered position. The assembly includes a hinge shaft connecting the toilet cover to the rear of the toilet so that it is rotatable together with the toilet cover between the lowered and raised positions. Connected to the hinge shaft is an automatic closure which is secured on the side of the toilet and includes a cylinder containing a volume of damper fluid and a rotor rotatably received within the cylinder. The rotor receives the hinge shaft to be rotatable together therewith and is provided with a flap extending outwardly into the damper fluid. The flap is pivotable relative to the rotor so that the to a folded condition when the seat cover is substantially no resistance to the upward When the cover is manually released from an the flap pivots to an unfolded position and damper fluid so that the cover descends slowly to the closed position.

British Patent No. 774,241 which was published May 8, 1957 to Thune is entitled DOOR CLOSURE. This patent describes a door closer hinge having a spring section and a fluid chamber section. The fluid chamber section is divided into two chambers by a stationary partition wall and a movable partition wall shaped as a flap.

The shortcoming in each of these apparatus is that none of the apparatus appear to accommodate a manual override of the damper mechanism to permit a manual override of the closure. Emergency situations arise wherein use of a toilet becomes urgent. In such situations, if a toilet seat is open or only partially closed,

it is not necessarily practical or possible to wait until the seat descends to a fully lowered position, which generally takes half a minute or so. Since no provision is made for forcibly closing the seats described above, a forced closure could damage the damper mechanism and/or the toilet seat or hinge assembly. A severe increase in fluid pressure created by a manual override of the damper mechanism could also damage the seals and/or the flap valve in these mechanisms.

United States Patent No. 5,279,000 which issued January 18, 1994 to Mercier et al. is entitled AUTOMATIC SEAT LOWERING HINGE ASSEMBLY. This patent describes an automatic toilet seat lowering hinge assembly having a chamber through which a shaft is disposed. The housing has a baffle extending from the inner surface of the housing to the surface of the shaft and a descent paddle that extends from the shaft outwardly toward the inner surface of the housing to partition the chamber into two compartments. An outer edge of the descent paddle includes a flexible tip seal which deflects under sufficient pressure to permit fluid to transfer from one side of the paddle to another. Thus, the closure may be manually overridden when temperature conditions permit the plastic tip seal to be adequately flexible. It does not appear, however, that this closure would be serviceable in unheated outdoor installations such as found in parks and the like.

DISCLOSURE OF INVENTION

It is an object of the invention to overcome the shortcomings of the prior art by providing an aesthetic, reliable and unobtrusive automatic closure mechanism for a toilet seat. It is a further object of the invention to provide an automatic closure for a toilet seat which is readily and economically manufactured.

It is yet a further object of the invention to provide an automatic closure for a toilet seat which mounts directly to a standard toilet fixture without additional hardware. In accordance with the invention there is provided an automatic closure mechanism with damping capability for controlling movement of a pivotable toilet seat assembly to permit the toilet seat assembly to be pivoted to a raised position

with little resistance while ensuring that the toilet seat assembly returns to a lowered position by a controlled closing action, unless the controlled closing action is overridden in which case the toilet seat assembly may be forcibly returned to a closed condition without damaging either of the automatic closure and the toilet seat assembly, the automatic closure mechanism including a stator and a cylindrical rotor rotatably received on the stator, the rotor being adapted for connection with the toilet seat assembly and the rotor and the stator defining a fluid tight reservoir containing a damper fluid, and a first flap valve and a second flap valve spaced-apart from each other and positioned in the fluid tight reservoir to define a first fluid chamber and a second fluid chamber, each flap valve being normally urged to a closed condition for defining the first and second fluid chambers, CHARACTERIZED IN THAT the first flap valve is hingedly mounted to an inner wall of the rotor, has a free edge and is adapted to rotate between a closed condition, wherein the free edge contacts a wall of the stator, and an open condition, wherein the free edge is spaced from the wall of the stator; and the second flap valve is hingedly mounted to the wall of the stator, has a free edge and is adapted to rotate between a closed condition, wherein the free edge of the second flap valve is adjacent the wall of the rotor, to an open condition, wherein the free edge is spaced from the wall of the rotor.

Thus, the invention in a first aspect provides an automatic closure mechanism for a closure assembly, such as a toilet seat or lid, the automatic closure providing a mechanism for damping the closing action of the closure assembly while ensuring that the damping action may be overridden by manual pressure to effect closure of the assembly without undue resistance. In order to provide this capability, the automatic closure assembly is constructed from a cylindrical rotor which rotates about an axial stator. A fluid tight reservoir is formed within the cylindrical rotor. Two flap valves mounted within the fluid tight reservoir control the rotation of the rotor. Each flap valve has a top and bottom edge and the bottom edge of each valve is provided with an anchor bulb which is rotatably received in an anchor cavity. The first flap valve is anchored to an inner side wall of the rotor and rotates from an open condition wherein the

top edge of the flap valve is adjacent the inner side wall of the rotor to a closed condition wherein the top edge abuts a side wall of the stator. The second flap valve is spaced apart from the first valve and mounted to the stator so that it is rotatable between a closed condition wherein its top edge is adjacent the inner wall of the rotor and a fully open condition wherein its top edge is adjacent the stator. Springs positioned at each end of the respective flap valves urge the flap valves to the closed condition. The springs on the first, or primary flap valve are less robust than the springs on the second, or relief, flap valve. When a hinge member connected to the rotor of the automatic closure is rotated as a seat connected to the hinge is rotated to a raised position, the weaker spring of the primary flap valve is overridden by fluid pressure and the primary valve opens to let the fluid flow by the valve so that the seat can be raised with substantially no resistance.

When the seat is moved toward a lowered position past the center of gravity of the seat so that gravity forces the seat closed, the damper fluid flows slowly around the side and ends of the flap valves so that the seat slowly descends to a closed position. If an urgent requirement for the seat occurs, manual pressure may be applied to the seat, in which instance the heavier spring of the relief valve is overridden and the seat may be forced to a lowered position with little further resistance. Thus, the closure damper mechanism is protected from damage and a reliable inexpensively constructed automatic closure mechanism is provided. In accordance with a further aspect of the invention there is provided an automatic closure assembly for a toilet seat which utilizes the automatic closure described above in conjunction with a coil spring that urges the seat to a lowered position. When the seat is rotated to the raised position, it rests against the toilet lid at an angle which is past the center of gravity with respect to a pivot point of the seat. Although the energy stored in the coil spring urges the seat to a lowered position, the fluid resistance in the automatic closure assembly and the action of gravity retains the seat in the raised position for two to five minutes depending on the viscosity of the fluid in the automatic closure. Once the coil spring has rotated the seat past its center of gravity, gravity assists the action of the coil spring to lower the seat to its lowered position on a top edge of the toilet bowl in

10-30 seconds, again depending on the viscosity of fluid in the automatic closure. If a seat that has been raised is required by someone who wishes to sit on the toilet, the raised seat can be forced to the lowered position using manual pressure. Manual pressure on the raised seat generates fluid pressure on the relief valve. The fluid pressure forces the relief valve to an open condition and the seat is readily lowered with little further resistance. Therefore, in emergency situations, the seat can be rapidly lowered without damaging the automatic closure, the seat, the hinge or the mounting bracket assembly.

Furthermore, the invention provides an automatic closure for a toilet seat which has substantially the same external appearance as a standard toilet seat and is adapted to be mounted to any standard toilet bowl without special fittings. Thus, there is no extraneous apparatus to clutter the toilet and inhibit cleaning or safe movement about the toilet area. While the closure mechanism in accordance with the invention is intended primarily for domestic fixtures, it is equally adapted to use in public washrooms where toilet seats are preferably maintained in a raised position rather than a lowered position. By reversing the orientation of the flap valves and the coil spring, a toilet seat is readily manufactured which normally rests in a raised position and is easily lowered for use. Such a seat will return to the raised position after a time interval which is dependent on the viscosity of the damper fluid in the automatic closure mechanism and the strength of the coil spring.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the invention will now be more fully explained by way of example only and with reference to the following drawings wherein:

FIG. 1 is a side elevational view of a toilet seat equipped with a closure mechanism in accordance with the invention, the toilet seat being mounted to a standard toilet fixture shown in phantom lines;

FIG. 2 is a rear elevational view of the toilet seat closure shown in FIG. 1 ; FIG. 3 is a top plan view of a rear portion of the toilet seat shown in FIGS. 1 and 2;

FIG. 4 is a longitudinal cross-sectional view taken along lines IV-IV of FIG. 3;

FIG. 5 is an enlarged cross-sectional view taken along lines V-V of FIG. 4;

FIG. 6 is an exploded view of the closure assembly in accordance with a preferred embodiment of the invention;

FIGs. 7a-e are cross-sectional views of the position of the flap valves in an automatic closure of the closure assembly in accordance with the invention during a normal operation, wherein:

FIG. 7a shows the toilet seat in a lowered position; FIG. 7b shows the toilet seat being rotated to a raised position;

FIG. 7c shows the toilet seat in a fully raised position;

FIG. 7d shows the toilet seat being lowered by the action of the automatic closure; and

FIG. 7e shows the toilet seat returned to the lowered position; and

FIGs. 8a-c are cross-sectional views of the action of the flap valves in the automatic closure of the closure assembly when the toilet seat is forcibly returned to a lowered position, wherein:

FIG. 8a shows the toilet seat in a raised position; FIG. 8b shows the toilet seat being forcibly lowered; and

FIG. 8c shows the toilet seat in a lowered position.

BEST MODE OF CARRYING OUT THE INVENTION

FIG. 1 shows a side elevational view of a preferred embodiment of a toilet closure, generally indicated by reference 10, in accordance with the invention.

The toilet closure 10 preferably includes a toilet seat cover 12, a toilet seat 14 and a closure mechanism 16, which is preferably an integral component of the toilet seat 14. The toilet seat also includes mounting brackets 18 that are adapted to fit any standard toilet fixture, generally indicated by reference 20 and shown in phantom lines.

FIG. 2 shows a rear elevational view of the toilet closure in accordance with the invention. As is readily apparent, the toilet closure is substantially identical in

appearance to a standard toilet closure assembly well known in the art. A distinct advantage of the closure mechanism in accordance with the invention is that it provides an economically manufactured toilet seat that automatically closes after a predetermined time interval. FIG. 3 shows a top elevational view of a rear portion of a toilet closure assembly 10 shown in FIG. 1. It is readily appreciated that the toilet closure assembly 10 in accordance with the invention provides a clean, neat appearance which permits ready access to a toilet fixture 20 for cleaning. The toilet closure assembly 10 also provides an uncluttered, aesthetically pleasing toilet closure assembly.

FIG. 4 shows a longitudinal cross-sectional view of the closure assembly 16, taken along lines IV-IV of FIG. 3. The closure assembly includes a cylindrical rotor 22 which is preferably an integral part of the rear portion of the toilet seat as can be seen in FIGS. 1-3. The closure assembly 16 also includes a stator 24 which is fixedly attached to the mounting brackets 18, as will be explained below in more detail with reference to FIG. 6. Provided on an outer side of each mounting bracket 18 is a hinge pin 26 which provides a pivot for the toilet seat cover 12 (see FIGS. 1-3). The closure assembly 16 is partitioned into a hydraulic section 30, hereinafter referred to as an automatic closure 30 and a dry spring section 36. The automatic closure 30 is delimited by an automatic closure center plate 32 and an automatic closure end plate 34. The construction and function of the automatic closure 30 is explained in detail below. The dry spring section 36 includes a coil spring 38 which engages a hole 40 in the stator 24 and a hole 42 in the rotor 22. The coil spring 38 stores energy generated when the toilet seat 14 is manually rotated to a raised position. The coil spring, therefore, urges the toilet seat to a lowered position.

FIG. 5 shows a cross-sectional view of the automatic closure 30 taken along lines V-V of FIG. 4. The automatic closure includes two flap valves which extend between the automatic closure center plate 32 and the automatic closure end plate 34 (see FIG. 4). A first flap valve, hereinafter referred to as the primary valve 46 is mounted to an inner wall of the rotor 22. A second flap valve, hereinafter referred to as the relief valve 48 is mounted to a relief valve mount 50 which is in

turn affixed to the stator 24 by an integral key 52 that engages a slot 54 in the stator 24. The relief valve mount 50 defines an edge of stator 24.

Each flap valve 46, 48 is respectively provided with an anchor bulb 56 on a bottom edge thereof. The anchor bulb 56 of the primary valve 46 is received in an anchor cavity 58 formed in an inner wall of the rotor 22. The anchor cavity

58 is shaped to. securely retain the primary valve 46 while permitting the primary valve to rotate from a closed condition shown in solid lines where a free edge of the primary valve abuts an edge of the stator 24 defined by the relief valve mount 50, to a fully open condition shown in phantom lines, where the free edge of the primary valve 46 is adjacent the inner wall of the rotor 22. Two torsion springs

60, respectively mounted to each end or side of the primary valve 46, constantly urge the primaiy valve to its closed condition. The relief valve 48 is received in an anchor cavity 62 formed in the relief valve mount 50. The anchor cavity 62 is shaped to permit the relief valve 48 to rotate from a closed condition wherein a free edge of the relief valve 48 is adjacent the-inner wall of the rotor 22, to a fully open condition shown in phantom lines where the free edge of the relief valve 48 is adjacent an inner edge of the stator 24, defined by the relief valve mount 50. Two torsion springs 64, respectively mounted on opposite ends or sides of the relief valve 48, constantly urge the relief valve to a closed condition. The torsion springs 64 are more robust than the torsion springs 60 on the primary valve 46, the purpose of which will be explained below. A stop 66 associated with the anchor cavity 62 prevents the relief valve 48 from rotating past a closed position.

FIG. 6 shows an exploded view of the components of the closure mechanism 16. The left mounting bracket 18 and the stator 24 as well as the left toilet cover hinge pin 26 are preferably molded from a resilient thermoplastic such as polyethylene, or the like, as an integral unit. Each component may, of course, be molded separately and heat welded or adhesively assembled as required. The stator preferably includes two integral cylindrical sections, the automatic closure section 30 and the dry spring section 36, the automatic closure section 30 being of a smaller diameter to accommodate the relief valve mount 50. This construction facilitates assembly as will be explained below.

The rotor 22 is preferably an integral part of the toilet seat 14. The rotor is a hollow cylinder having a closed left end with a bore for accepting the dry spring 36 of the stator 24 (see FIG. 4) and an open opposite end for accepting the automatic closure end plate 34. The spring 38 is attached to the rotor and the stator as explained above. The automatic closure center plate is installed against the free end of the dry spring section 36 and an 0-ring 68 is slipped over the automatic closure section 30 of the stator shaft. The relief valve mount 50 is slid over the stator shaft 24 after the relief valve 48 is fitted in the anchor cavity 62 in the relief valve mount 50 (see FIG. 5), and the primary valve 46 has been mounted in the anchor cavity 58 in the inner wall of the rotor 22 (see FIG. 5).

The fluid reservoir in the automatic closure 30 (see FIG. 4) is filled with a damper fluid of an appropriate viscosity, a vegetable oil for example, and a second 0-ring 68 is slid over the stator shaft. The automatic closure end plate 34 is then attached to the end of the rotor 22 using a threaded connector, an adhesive or some other appropriate method of producing a fluid tight seal. The mounting bracket 18 for the right side is attached to the free end of the stator shaft 24, and assembly of the closure mechanism 16 is complete.

FIGs. 7a-7e show a typical normal operation sequence of the automatic closure section of the closure mechanism 16. FIG. 7a shows the position of the flap valves when the toilet seat is in a lowered position. In the lowered position, the primary valve 46 and the relief valve 48 are both closed and a damper fluid 70, is at equilibrium. When a user raises the toilet seat 14, a fluid pressure degenerated by the displacement of the primary valve 46 in the damper fluid 70 causes the tension of the primary valve springs 60 to be overridden and the valve opens. Since the relief valve spring 64 is more robust, the relief valve remains closed as shown in FIG. 7b. After the seat is moved to the fully raised position shown in FIG. 7c, the fluid pressure reaches equilibrium and the primary valve 46 returns to a closed condition. When the toilet seat 14 is in the fully raised position shown in FIG. 7c, the toilet seat rests against the toilet seat cover 12 (see FIG. 1) which in turn generally rests against a front side of the toilet tank (not illustrated). In this position, the energy generated in the coil spring 38 (see FIG. 4) acts to urge the toilet seat 14 toward the lowered position. The primary valve

46 and the relief 48 are closed, however, and the damper fluid 70 cannot readily escape from the fluid chamber between the primary valve and the relief valve. Although, as described above, the free edge of the relief valve 48 in its closed position is adjacent the inner edge of the stator 24, the free edge of relief valve is distanced therefrom by a narrow gap 71. The damper fluid 70 is, therefore, forced slowly through a very narrow gap 71 along the free edge of the relief valve 48. The springs 64 at each end of the relief valve 48 are sufficiently resilient to resist the fluid pressure degenerated by the force exerted by the coil spring 38 so that the relief valve 48 remains in its closed condition. The seat, therefore, remains in the raised position for a period of 1-5 minutes or longer, depending on the viscosity of the damper fluid 70, even though it constantly creeps towards the lowered position.

FIG. 7d shows the toilet seat after the coil spring 38 has forced the seat past its center of gravity and gravity assists the coil spring in returning the seat to the lowered position. With the assistance of gravity, the damper fluid 70 is forced past the relief valve 48 at a faster rate and the descent of the seat increases so that full closure from that point typically requires about 10-30 seconds, depending on the viscosity of the damper fluid 70.

FIG. 7e shows the seat returned to the fully lowered position, the damper fluid 70 having- reached equilibrium between the closed primary valve 46 and the relief valve 48.

FIGs. 8a-8c illustrate what occurs when the toilet seat 14 is forced to the lowered position so that the toilet is available for use in a sitting position. Emergency situations may require that a toilet seat be lowered for immediate use. Prior art closure mechanisms generally do not accommodate an override of a damping mechanism. Prior art closure mechanisms may, therefore, be damaged if a toilet seat is forced down in an emergency situation.

The closure mechanism 16 permits manual override of the closure damper. As shown in FIG. 8a, the toilet seat 14 is in the raised position. As noted above, closure from this position will normally require about 1-5 minutes, depending on the viscosity of damper fluid 70. The toilet seat may be forcibly lowered, however, by manual override of the damping action of the automatic closure 30.

FIG. 8b shows the position of the Primary valve 46 and the relief valve 48 when the closure damper is manually overridden. As is apparent, due to the position of primary valve 46, it cannot be forced past the closed condition while the toilet seat is being lowered. The relief valve 48 can, however, be forced to an open condition against the bias of the relief valve springs 64. Manual pressure on the toilet seat 14, therefore, forces the relief valve 48 open and the damper fluid 70 flows readily past the relief valve to permit a user to lower the toilet seat 14 with very little further resistance. Once the toilet seat 14 is in the lowered position shown in FIG. 8c, the pressure of the damper fluid 70 between the primary valve 46 and the relief valve 48, is dissipated and the relief valve 48 returns to closed its position.

Although the preferred embodiment of the invention has been described above with reference to a specific toilet seat construction, it will be understood by those skilled in the art that the principles described may be applied to other closures and constructions not described above. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.

INDUSTRIAL APPLICABILITY

The invention provides a simple, durable automatic closure mechanism for closing a seat and/or seat cover. The automatic closure mechanism cannot be damaged by a manual override of the damping mechanism, therefore providing a mechanism that can function reliably for an extended period of time. In accordance with a preferred embodiment of the invention, the automatic closure mechanism is integrated with a toilet seat, providing an automatically closing toilet seat with a neat, trim appearance which is aesthetic and unobtrusive.

The invention also provides an automatic closure mechanism that is readily and economically manufactured from inexpensive molded plastic components that are readily integrated into a toilet seat structure. Thus, a toilet seat is provided which can be offered as a standard component of new toilet fixture units without contributing significantly to the unit cost. In addition, an automatically closing toilet seat that fits standard toilet seat mounts and may be reasonably priced is also provided.

The automatic closure mechanism in accordance with the invention is also designed to operate in automatic or override mode at practically any temperature. Therefore, a toilet seat with automatic closure is provided which is operative in unheated buildings in cold climates.