Abstract:
A hydraulically lifted toilet seat. A hydraulic linear actuator mounted within a lift unit rigidly attached to the toilet bowl unit utilizes utility water pressure to provide a force to lift the toilet seat. In a preferred embodiment a drive arm of the hydraulic linear actuator applies a tension force to a flexible tension element which is in turn attached to a sheave that is rigidly attached to an axle rigidly attached to the toilet seat. Actuation of the drive arm of the linear actuator causes the sheave, axel and the toilet seat to pivot about 100 to 110 degrees from a horizontal position to a raised position leaning against the toilet tank. In the preferred embodiment the flexible tension element is a nylon cord attached to the sheave through a pulley. In this preferred embodiment the hydraulic linear actuator is controlled by a spring loaded three-way valve or two two-way spring loaded valves permitting users to raise or lower the seat by temporally positioning valve handles up or down. In this embodiment the pressure line to the actuator is connected to a vent line to a float cutoff valve in the toilet tank so that when the toilet is flushed, pressure in the hydraulic linear actuator is relieved causing the toilet seat to lower to its horizontal position each time the toilet is flushed. Embodiments are provided that come in kit form to permit easy installation without plumbing expertise on almost any toilet in the United States.

Description:
[0001]    The present invention relates to devices for raising and lowering toilet seats and toilet lids and in particular for hydraulic devices for raising the seats and lids. 
       BACKGROUND OF THE INVENTION 
       [0002]    Flush toilets consist of a bowl and a device for flushing the contents of the bowl down a sanitary drain. Almost all flush toilets have a detachable hinged toilet seat (mostly made now days of plastic) and almost all toilets installed in residences include a hinged lid. Features of particular toilets found in many residences are shown in  FIGS. 1A through 1E . These toilets comprise a toilet seat  2  and a toilet seat cover  4 . Other features are the toilet bowl unit  6  and the water tank  8 . The tank typically has a tank cover  10 . The cover  4  and the seat  2  pivot about a pivot axis  12  in each of two hinge units  14 A and  14 B. The hinge units are rigidly mounted to the bowl unit in each case with a bolt, washer and nut with the bolt passing through a frame portion of bowl unit  6 . The cover and seat is typically lifted by hand by men and boys so they can pee in the bowl without wetting down the seat. Girls and women typically lift the cover by hand. However since they pee sitting down, they rarely lift the seat. In fact, this can lead to a big problem especially in residences where only women live, since the girls and women grow accustom to the seat being in a down position. A man or boy visiting will typically leave the seat in the up position after peeing. Then the girl or woman comes in to use the toilet sometimes will sit down thinking the seat is down when it is not. The result can be very disturbing and can in some cases lead to injuries. To solve this problem, several techniques have been proposed to return the seat to the down position after it has been raised. For example, see U.S. Pat. Nos. 5,400,442, 5,343,571 and 5,884,342. 
         [0003]    Most toilets in public locations comprise a hinged toilet seat but no seat cover and have the general features shown in  FIGS. 2A and 2B . The seat has the general shape of a C as shown in  FIG. 2B  instead of the general O shape as in the residential unit. Public rest rooms in the United States are usually equipped with a dispenser holding paper toilet seat covers that the user can place over the toilet seat so that his skin does not touch the seat. Some people lift and lower the seat in public places with their shoe, since they prefer not to touch the seat with their hand. Many designs have been proposed for devices that permit users to raise and lower toilet seats without touching them. Many such designs include a foot powered mechanism with gears and levers configured to raise and lower the seat or the seat and the lid. Other devices are motor driven with remotely located push button controls. Several designs are hydraulically powered with flush water pressure providing the energy to raise and/or lower the seat and/or lid. Examples of prior art hydraulically operated toilet seats are U.S. Pat. No. 4,291,422 to Shoemaker et al and U.S. Pat. No. 5,774,904 to McWilliams. 
         [0004]    Although many remotely lifted toilet seats have been proposed and many patents exist covering various designs for remotely lifted toilet seats, none, to the best of Applicants knowledge, have become widely utilized. 
         [0005]    What is needed is a better remotely lifted toilet seat. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention provides a hydraulically lifted toilet seat. A hydraulic linear actuator mounted within a lift unit rigidly attached to the toilet bowl unit utilizes utility water pressure to provide a force to lift the toilet seat. In a preferred embodiment a drive arm of the hydraulic linear actuator applies a tension force to a flexible tension element which is in turn attached to a sheave that is rigidly attached to an axle rigidly attached to the toilet seat. Actuation of the drive arm of the linear actuator causes the sheave, axel and the toilet seat to pivot about 100 to 110 degrees from a horizontal position to a raised position leaning against the toilet tank. In the preferred embodiment the flexible tension element is a nylon cord attached to the sheave through a pulley. In this preferred embodiment the hydraulic linear actuator is controlled by a spring loaded three-way valve or two two-way spring loaded valves permitting users to raise or lower the seat by temporally positioning valve handles up or down. In this embodiment the pressure line to the actuator is connected to a vent line to a float cutoff valve in the toilet tank so that when the toilet is flushed, pressure in the hydraulic linear actuator is relieved causing the toilet seat to lower to its horizontal position each time the toilet is flushed. Embodiments are provided that come in kit form to permit easy installation without plumbing expertise on almost any toilet in the United States. Embodiments of the present invention are also provided that utilize electric controlled valves to control the hydraulic linear actuator to raise and lower the seat. 
     
    
     
       BRIEF DESCRITION OF THE DRAWINGS 
         [0007]      FIGS. 1 through 1E  show features of a prior art residential toilet. 
           [0008]      FIGS. 2A and 2B  show features of a prior art public toilet. 
           [0009]      FIGS. 3 and 3A  show features of a toilet seat lift mechanism according to the present invention with the toilet seat in the down position. 
           [0010]      FIGS. 4 and 4A  show features of a toilet seat lift mechanism according to the present invention with the toilet seat in the up position. 
           [0011]      FIGS. 5A ,  5 B and  5 C show a three way valve for controlling the above lift mechanism. 
           [0012]      FIGS. 6A through 6F  show various positions of the toilet seat, the lift mechanism and the lift mechanism control valve. 
           [0013]      FIGS. 7A and 7B  show an aquarium shutoff float valve used as an actuator drain when the toilet is flushed. 
           [0014]      FIGS. 8A ,  8 B, and  8 C show a seat position control technique using two two-way valves. 
           [0015]      FIGS. 9A and 9B  show technique for toilet seat position control with electric operated valves. 
           [0016]      FIG. 10  shows a seat control actuator with a push type actuator. 
           [0017]      FIGS. 11A ,  11 B and  11 C show features for mounting embodiments of the present invention on virtually any toilet. 
           [0018]      FIG. 12  show embodiment of the present invention using mechanical operated valves. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     First Preferred Embodiment 
       [0019]    A first preferred embodiment of the present invention can be described by reference to  FIG. 3  to  FIG. 7B . This embodiment preferably is sold as a kit that can be easily installed without any special equipment as replacements for regular toilet seats or regular toilet seats and seat covers. Preferred embodiments of the kit will fit nearly all toilets. Power to raise and lower the seat is provided by utility water pressure with the user providing control by operating a control valve with no need for the user to touch the seat. 
       Lift Mechanism 
       [0020]      FIGS. 3 and 3A  show features of a toilet seat lift mechanism  20  according to the present invention with the toilet seat in the down position and  FIGS. 4A and 4B  show those features with the toilet seat in the up position.  FIGS. 6A through 6E  show the mechanism for lifting a toilet seat of the type used in public toilets of the type shown in  FIGS. 2A and 2B , but it can also be used applied to lift seats such as seat  2  shown in  FIG. 1 . The lift mechanism  20  is contained in a lift mechanism housing  22  that is bolted to a toilet bowl unit with bolts through bolt holes that are common in prior art toilets as described in the background section. Mechanism  20  includes a hydraulic linear actuator  24  which in this preferred embodiment is a slightly modified off-the-shelf version of Part No. DNSU supplied by Automation Controls with offices in Hauppauge, N.Y. It includes an approximately two-inch diameter piston that produces a linear force of 204 pounds with water pressure of 65 psi and a linear travel of about two inches. Actuator  24 , with its modified actuator arm  26 , is positioned as shown in  FIGS. 3 and 4 .  FIGS. 3 and 3A  show the mechanism with toilet seat  2  in its down position and  FIGS. 4 and 4A  show the mechanism with seat  2  in its up or its 110 degree raised position. Attached to the end of actuator arm  26  is flexible tension element  28  which in this case is a nylon cord. As shown in  FIGS. 3 and 3A , flexible tension element  28  wraps 450 degrees around 1¼ inch pulley  30  mounted on post  32  and attaches to axle sheave  34  at location  36  which is about 110 degrees around sheave from the point where tension element  28  intersects sheave  34  with toilet seat  2  in its down position as shown in  FIGS. 3 and 6A . The power source for actuating actuator  24  is utility water pressure, the same water pressure that is used to flush the toilet. Utility water under pressure (in the range of about 65 psi) enters actuator  24  through water line  38  as shown in  FIGS. 3 and 4 . This water pressure causes modified actuator arm  26  to advance from its position shown in  FIG. 3  to its position shown in  FIG. 4  about 1¼ inch pulling tension element  28  about 1¼ inch. Tension element  28  acts through pulley  30  to pivot sheave  34  about 110 degrees. Sheave  34  is rigidly attached to axle  38  that is rigidly attached to seat  2  through seat lift arms  40  so the 110 degree pivot of sheave  34  causes seat  2  to pivot upward about 110 to rest against water tank  8  as shown in  FIG. 6B . The utilization of a flexible nylon tension unit  28  allows the lid to be raised manually without activating the actuator  24 . 
       Control of Lift Mechanism 
       [0021]    In this preferred embodiment lift mechanism  20  is controlled by three-way spring positioned valve  42  as shown in  FIGS. 5A ,  5 B and  5 C and  6 A through  6 E. The neutral position of this valve is shown in  FIG. 5B . Hand force is required to position the valve in positions  5 A and  5 C. In the  5 B position the valve is closed and no water passes through. In position  5 A the valve connects actuator  24  to utility water pressure line  44  as shown in  FIG. 6A  to provide approximately 65 psi water pressure to actuator  24 . In position  5 C valve  42  connects actuator to drain line  46  to drain actuator  24  into water tank  8  as shown in  FIG. 6D . Actuator  24  is also drained through drain line  47  by flushing the toilet. Aquarium float shutoff valve  60  as shown in  FIGS. 7A and 7B  is closed when tank  8  is full and open when the water level is low. 
       Utility Water Supply Attachment Unit 
       [0022]    In this preferred embodiment water supply attachment unit  48  is provided as a part of a standard kit to provide a pressurized water supply to actuator  24 . This water supply attachment unit includes a standard tube connection coupling  50  and a threaded tube connection section  52  which is equivalent to the standard 7/16 inch tubing on standard toilet tank connections. The attachment unit also includes a pipe section  54  a ¼ inch O.D. tube connection  56  for connecting water pressure line  44  to provide water under pressure to actuator  24 . This attachment unit permits an easy connection to utility water pressure without the need of special plumbing skills. 
       Raising and Lowering the Seat 
       [0023]    Operation of this first preferred embodiment is explained by reference to  FIGS. 6A through 6E .  FIG. 6A  shows features of the embodiment with the seat in the down position. Valve  42  is in its neutral closed position. No pressure is applied to actuator  24  and seat  2  is in its down position. Tank  8  is full. 
       Raising the Seat 
       [0024]    In  FIG. 6B  valve  42  is moved by a user to its raised position as shown at  64  so that actuator  24  is connected by valve  42  to 65 psi utility water pressure through water supply attachment unit  48 . Water flows according to arrows  66  as shown in  FIG. 6B . Actuator arm  26  of actuator  24  is driven about 1¼ inch as shown by comparing  FIG. 6B  to  FIG. 6A  which causes seat  2  to rise to the position shown at  68  in  FIG. 6B .  FIG. 6C  shows the condition of the elements of the present invention after the raising of seat  2 . No water is flowing and seat  2  remains in its up position, held there by trapped pressure in actuator  24 . 
       Lowering the Seat 
       [0025]    In  FIG. 6D  valve  42  is moved by a user to its lower position as shown at  70  so that actuator  24  is connected by valve  42  to drain line  46 . Water flows out of actuator to tank  8  as shown by arrows  74  in  FIG. 6D . Spring element  76  attached to axle  38  as shown in  FIG. 6C  is positioned to apply a lowering torque to axle  38  when the seat  2  is in a position higher than about 70 degrees. At 70 degrees spring element  76  presses against the bottom of tank  8 . So once the water pressure in actuator decreases to atmospheric, spring element  76  causes seat  2  to rotate to about 70 degrees. This causes a rotation of sheave  34  which through tension element  28  drives actuator arm  26  pushing water out of actuator  24 . Once seat is rotated to about 70 degrees gravity will take over causing it to lower slowly to its horizontal position driving actuator arm  26  to its withdrawn position as shown at  72  in  FIG. 6D  as the remaining water is forced out of the actuator. 
       Flushing Automatically Lowers the Seat 
       [0026]      FIG. 6E  shows what happens if seat  2  is left in its up position after use by a man or boy when the toilet is flushed. The flushing of the toilet causes the water level in tank  8  to drop. This opens aquarium float shutoff valve  60  as shown in  FIG. 7A  allowing the action of spring element  76  and the weight of seat  2  to force the water out of actuator  24  and forcing seat  2  to lower slowly to its horizontal position. The flow of water is shown by arrows  80  in  FIG. 6E . The rising of water level in tank  8  closes valve  60  as shown in  FIG. 7B . 
       Two Two-Way Valves Replacing the Three-Way Valve 
       [0027]    An alternative to the three-way control valve shown in  FIGS. 5A ,  5 B and  5 C is two two-way valves. In this case two two-way valves can be used as shown in  FIGS. 8A ,  8 B and  8 C. These are spring operated valves with the neutral position as shown in  FIG. 8B . To raise the seat a user should operate valve  42 A as shown in  FIG. 8A  and to lower the seat the user should operate valve  42 B as shown in  FIG. 8C . 
       Electric Controlled Valves 
       [0028]    Instead of the manually operated valves described above and shown in  FIGS. 5A  though  6 E, actuator  24  can be controlled by electric actuated valves.  FIG. 9A  shows control using a three-way electric controlled valve  52 .  FIG. 9B  shows similar control using two two-way electric control valves  52 A and  52 B. The functioning of the remainder of the system is the same as described above for the manually controlled valves. The valves  52  and  52 A and  52 B in  FIGS. 9A and 9B  are controlled by electric switches  50  as shown in  FIGS. 9A and 9B . These switches can be finger operated switches or switches  50  could be remotely operated switches using a signal transmitter and receiver. The signal transmitter and receiver could be an infrared device or it could be a device operated at radio frequencies. Such devices are readily available from many suppliers. 
       Pushing Actuator 
       [0029]    Actuator  24  can be configured to operate in a push mode as shown in  FIG. 10  instead of the pull configuration in  FIGS. 3 ,  3 A,  4  and  4 A and  FIGS. 6A through 6E . In this case pulley unit  30  is replaced by a cam  30 A that is pushed by actuator  24  instead of being pulled. The reader should note that this drawing shows the components of the seat raising unit to occupy only one half of lift mechanism  20 . This leaves room for an equivalent mechanism and controls for controlling the positioning of seat cover  4  as shown in  FIG. 1 . Preferably the control mechanism for cover  4  would be substantially the same as described for seat  2  and the axel for cover  4  would be positioned at a higher level than axel  76  for seat  2 . 
       Remotely Controlled Embodiment 
       [0030]    Applicant currently expects to provide a preferred embodiment for use with toilets similar to the one shown in  FIG. 1 . The unit will be marketed as a kit and will contain hydraulic controls for both the seat  2  and cover  4 . Each of the hydraulic devices will be controlled by a two-way miniature battery operated solenoid valves each of which in turn will be actuated by a battery powered, radio frequency transmitter and receiver unit. The transmitters preferably will be mounted at a convenient location on the bathroom wall and the receivers will be located adjacent to the valves. Each transmitter is actuated by button control unit. These remote transmitter/receiver units can be provided by many suppliers such as Aerotech with offices in Pittsburgh, Pa. and the miniature valves are available from suppliers such as Asco Scientific with offices in Orange, Calif. The kit is expected to include an infrared sensor unit that will be adapted to lower the seat when there is no one in the vicinity of the toilet for a specified period of time. 
       Mounting the Preferred Embodiments 
       [0031]    In all toilets known to Applicants two holes are provided on each toilet to mount the toilet seat or toilet seat and the toilet lid if there is one. However, the two holes are not spaced at a standard dimension. The distance between the holes varies from 5¼ inches to 8½ inches. A mounting unit is shown in  FIGS. 11 ,  11 A and  11 B which comes as a part of a kit to permit preferred embodiments of the present invention to be installed easily on almost any toilet in the United States. The mounting unit is comprised of two mounting brackets  60 A and  60 B. Bracket  60 A is I shaped and  60 B is L shaped. Both have a hollow threaded post  62  that extends through the two seat mounting holes on virtually every toilet in the United States. The two mounting brackets are firmly mounted to the toilet with nuts  64 . Each of the two mounting brackets have two threaded studs  66  extending upward as shown in  FIG. 11A . These threaded studs extend upward through slots  70  in the bottom  68  as shown in  FIG. 11B  of lift mechanism housing  22 . These slots permit easy attachment of the lift mechanism to toilets with wide variation in the distance between the two mounting holes. Therefore the location of the lift mechanism  20  is not dependent on the attachment holes in the stool. Lift mechanism  20  is firmly attached to the toilet structure by four nuts (not shown) attached to the four studs shown in  FIG. 11B . Housing  22  of lift mechanism  20  is fitted with a rubber base edge to seal against the stool base between the seat  2  and the tank  8 . Actuator fill/vent line  72  passes through hollow threaded post  62  and slot  74  in bottom plate  68  to connect to actuator  24 . 
       Other Design Considerations 
       [0032]    The actuator size is controlled by three main factors. The force required to lift the lid, the internal return spring space, and the cable sheave diameter. The smaller the sheave diameter the larger the force required to lift the lid. The larger the force the greater will be the actuator diameter. The spring force of spring  76  is controlled by the ‘stack’ distance and the lb-inch force to return the actuator piston. An open vent line may be provided connecting the air portion of actuator  24  to tank  8  this line could pass through one of the hollow threaded posts  62  to allow any water that might get past the lip seal of actuator  24  to be returned to the tank  8 . With the electronic valves, an infrared sensor can be provided that will sense when no one is in the stool area and operate the control valve to lower the seat. 
         [0033]    Three-way miniature solenoid valves at a single unit price less than $8 appear to be available from at least two vendors. While a specific valve to the specifications required for the compact assembly has not been identified, both vendors claim able to adjust their existing products to satisfied needs. Piezoelectric valves were examined to see if they were able to provide the service since they require very little power to operate. They are not able to meet the needs and are very expensive. The battery size required to operate the remote controls and solenoid valves is expected to be 9 volts DC or less. Valves with ⅛ inch connections provide ample water flow for the operation required. 
         [0034]    Preferred embodiments of the present invention have been described in detail above. However, a great many variations from these specific embodiments could be made and will be obvious to persons skilled in the art to which this invention belongs. For example, as suggested above the techniques described for lifting seat  2  could also be used to lift seat cover  4 . Lift mechanism housing  22  could contain two lift mechanisms, one for the seat and one for the cover. For the battery operated electronic embodiments, water flow to the toilet could be harnessed to generate enough electric power to recharge batteries needed for operating the solenoid valves to lift the seat(s). The following features could be provided to accommodate someone who manually lifts a lid. For the manual valve concept, a manual valve could be added in the housing to be triggered when the lid is lifted in order to fill the actuator and hold the lid up against the spring return force. For the solenoid valves, a magnet on the sheave could be used to detect the manual raising of the seat so that when the seat is raised, a signal can be sent that will trip the fill valve to keep the lid up. Therefore, the scope of the invention should be determined by the appended claims and their legal equivalence and not by the specific embodiments described above. The primary functions of the actuators, piston returns, top and bottom lid lifting and lowering, manual and solenoid valve operations, have been tested successfully on a proof-of-principle test bed.