Abstract:
A bath lift system comprises a seat which is raised and lowered inside of a bath by a lifting device positioned inside the bath. The lifting device provides an aesthetically appealing system with the seat substantially concealing the lifting device, thus obscuring its view. The lifting device reduces leakage while providing straight line movement positioning of the seat from a central position to a position along side of the top rim of the bath. Also, an alternative internal lifting device that eliminates the need for openings through the wall of the bath is provided.

Description:
SPECIFICATION 
     CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
     Not applicable. 
     FIELD OF THE INVENTION 
     This invention relates generally to a bath system for raising and lowering an individual in and out of a bath, and more particularly, to a bath system with a seat and a lifting device, where the lifting device is positioned within the bath, substantially out of sight. 
     BACKGROUND OF THE INVENTION 
     Bath lifting systems have been available in the past to raise and lower individuals in and out of a bath. For example, U.S. Pat. No. 2,361,474 proposes a bath lifting system for raising and lowering an individual in and out of a bath using two exposed U-shaped crankshafts. A table spanning the shafts is connected to the bights of the U-shaped crankshafts. The crankshafts rotate in unison to rotate the table from a lowered position within the bath to a raised or extended position out of the bath. 
     Another bath lifting system is proposed in U.S. Pat. No. Re. 33,624. This system proposes a lifting device on the outside of the bath connected to a seat support member that extends through the bath wall. In particular, the seat support member extends through an elongated wall opening, or slot, to lift the seat from a lowered position to a raised position. 
     Yet another bath lifting system is proposed in U.S. Pat. No. 5,146,638. This system proposes a telescoping lifting column which is positioned in an upright position through one end of the upper rim of a bath. The lifting column includes a first actuator that vertically raises and lowers the seat in and out of a bath. A second actuator then swivels or rotates the lifting column about its cylindrical axis to position the front portion of the seat from a central position in the bath to a position over the rim of the bath. If desired, the seat can be swiveled through a smaller angle from its central position in the bath for transfer from a wheelchair to the seat. 
     Many other bath lift systems, available in the past, have an appearance that is bulky and mechanical. In particular, exposed lifting devices located adjacent to the bath are not considered aesthetically appealing. In the lifting devices positioned out of sight behind a side bath wall and extending through the upper rim of the bath, dual actuators, electronic circuitry and mechanical parts are proposed to provide a two step movement to first raise the seat and then swivel the seat, even if only to swivel the seat a preferred smaller angle from a central position to position the seat for transfer from a wheelchair. (See &#39;638 patent, col. 3, In. 62 to col. 4, ln. 41). Also, support members which extend through an elongated opening or slot in the bath wall, that begin at the bottom of bath in the drain area, are particularly susceptible to seal wear and resulting water leakage from the area where fluids collect caused by the sliding movement of the member that extends through the wall. 
     Therefore, an aesthetically appealing lifting device, concealed behind the seat, would be desirable. Moreover, a lifting device substantially concealed behind a lift seat that reduces leakage while providing straight line movement positioning of the seat from a central position to a position along side of the rim of the bath for transfer from a wheelchair would be desirable. 
     SUMMARY OF THE INVENTION 
     According to the invention, a bath that substantially conceals the lifting device behind the seat and reduces leakage while providing straight line movement to position the seat from a central position to a position along the side of the rim of the bath for transfer from a wheelchair is disclosed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The object, advantages, and features of the invention will become more apparent by reference to the drawings which are appended hereto and wherein like numerals indicate like parts and wherein an illustration of the invention is shown, of which: 
     FIG. 1 is a cut-away side elevational view of the preferred embodiment of the bath lift system with the seat in the lowered position; 
     FIG. 2 is a view similar to FIG. 1 with the seat in the raised position; 
     FIG. 3 is a top view of the bath lift system as shown in FIG. 1, with the seat also shown in phantom view in its rotated position; 
     FIG. 4 is a view taken along line  4 — 4  of FIG. 1; 
     FIG. 5 is a view taken along line  5 — 5  of FIG. 2, with the seat alga sown in phantom view in its rotated position; 
     FIG. 6 is a side elevational view taken along line  6 — 6  of FIG. 3 showing the lifting power system of the preferred embodiment; 
     FIG. 7 is a side elevational view, similar to FIG,  6 , showing the seat in the raised position; 
     FIG. 8 is a perspective view of the preferred embodiment looking down, and towards the back of the bath, with the seat removed, to better illustrate the lifting device; 
     FIG. 9 is a view of the bath taken along line  9 — 9  of FIG. 8 showing a cross section view of the seat rotation assembly; 
     FIG. 10 is a cut-away side elevational view of an alternative embodiment A of the present invention showing the seat in the lowered position; 
     FIG. 11 is a view similar to FIG. 10 of an alternative embodiment A of the present invention showing the seat in the raised position; and 
     FIG. 12 is a side elevational view of an alternative embodiment B of the present invention showing the seat in the raised position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The bath lift system of the present invention is shown in the Figures (FIGS.) In particular, the preferred embodiment of the bath lift system is shown in FIGS. 1-9 and alternative embodiments are shown in FIGS. 10-12. 
     The preferred embodiment comprises: a bath, generally indicated at  20 , seat, generally indicated at  22 , guiding assembly, generally indicated at  26 , lifting device, generally indicated at  28 , and lifting power system, generally indicated at  30 . As shown in the Figures, bath  20  includes bath walls  24 A,  24 B,  24 C,  24 D, and bath bottom  24 E, along with other standard bath features including openings  24 F and  24 G for drains. This preferred embodiment includes a seat recess  36  in the bath bottom  24 E and channel recess  38  for communicating fluid from the seat recess  36  to the drain opening  24 F. Other recess formations may be used or no recess formations could be used. Also, other embodiments may relocate standard bath features, such as the drain, or may modify standard bath features, for example, by using multiple drains. In addition, other embodiments may use a hot tub, pool, a whirlpool bath or shower in place of a bath. 
     Seat  22 , preferably fabricated from a non-corrosive material such as plastic, can be seen in FIGS. 1-7. Seat  22  is sized and positioned to substantially obscure the view of both the guiding assembly  26  and the lifting device  28 , when seat  22  is in the lowered position. As best shown in FIGS. 2,  8  and  9 , seat  22  is rotatably attached to a seat rotation assembly, generally indicated at  40 , via seat bottom  22 A. As best shown in FIG. 9, seat bottom  22 A is attached to rotor  48  of rotation assembly  40  by means of stainless steel bolts  56 . Rotor  48  rotates about post  50  within housing  44  of rotation assembly  40  and is secured about post  50  via securing ring  54 . Rotor  48  rotates within housing  44  contacting bearings  52  and bushings  58 . Housing  44  is preferably integral with cantilevered seat bracket  46 , which is in turn attached to guiding assembly  26 . Other embodiments may not substantially obscure the view of guiding assembly  26 , such as with an opening in seat back  22 B. In addition, other embodiments may exclude rotation assembly  40  and directly fixedly attach the seat bottom  22 A directly to the seat bracket  46 . 
     As best shown in FIGS. 2,  3  and  5 , locking pin, generally indicated at  60 , along with pin holes  62  and  64  in rotation assembly  40  are used to lock seat  22  into predetermined desired positions. Locking pin  60  has a pin head  75 , a left and right (when viewing FIG. 2) shaft portions,  66  and  68 , respectively, separated by collar  70  therebetween. Left shaft portion  66  extends through seat bottom extension  72 . Right shaft portion  68  extends through seat bottom opening  74 . Collar  70  is urged away from seat bottom opening  74  by a coil spring  76  compressed between collar  70  and seat bottom opening  74  to urge the end of locking pin  60  to contact the cylindrical exterior  40 A and the desired pin holes  62  and  64  of rotation assembly  40 . Locking pin hole  62 , located on the front cylindrical exterior  40 A of rotation assembly  40 , is located in the rotation path of locking pin  60 . When the desired pin hole is aligned with locking pin  60 , coil spring  76  urges locking pin  60  to be received in selected pin hole to lock the seat in the desired position as shown in FIG.  2 . Locking pin hole  64 , preferably located 90° from hole  62  on the side of the cylindrical exterior  40 A of rotation assembly  40 , is also located in the rotational path of locking pin  60 . When the locking pin  60  engages pin hole  64  the seat  22  is locked in the lateral position, as shown in phantom view in FIGS. 3 and 5. Other alternative embodiments may use other forms of locking mechanisms and locked positions. 
     Guiding assembly  26  of the preferred embodiment is best shown in FIGS. 1,  2 ,  4 ,  5 ,  7  and  8 . In the preferred embodiment, the guiding assembly  26  is made up of first set of arms  34 A and  34 B and second set of arms  80 A and  80 B, and the entire assembly is mounted to wall  24 A at an angle Ø, as best shown in FIG. 5, with respect to the bottom  24 E of bath  20 . The angle Ø at which the arms are attached is such that when the seat is in the lowered position, the seat is located substantially along the longitudinal axis D of the bath, as best shown in FIG. 3, and when the seat is in the raised position, the seat overlaps the top of the side wall  24 D of the bath, as best shown in FIG.  5 . In the preferred embodiment, both sets of arms are attached at one end to the bath wall  24 A and at the other end to seat bracket  46 . As best shown in FIGS. 1,  2 ,  4  and  5 , the second set of arms  80 A and  80 B are pivotally attached at one end to upper wall rod  82  and at the other end to upper seat rod  84 . Upper wall rod  82  is, in turn, attached to bath wall  24 A via attachment blocks  81 A and  81 B. The first set of arms  34 A and  34 B are fixedly attached at one end to rotatable member  32 , and, at the other end, to lower seat rod  86 . Rotatable member  32  is attached to bath wall  24 A via attachment blocks  83 A and  83 B. Other alternative embodiments may use a single first arm and a single second arm, and others only a structurally stable first set of arms, and yet others with only a single first arm. Also, other alternative embodiments may mount any existing first or second sets of arms horizontally, rather than at an angle Ø to the bottom of the bath. Other embodiments may not use rods that extend the fall width of the bath, but rather, only extend between the side of the bath and the connection arm(s). Yet even other alternative embodiments may utilize different types of guiding assemblies which transform rotational movement into vertical displacement of the seat. 
     Lifting device  28  can best be seen in FIGS. 1,  2 ,  3 ,  4 ,  5 ,  6 ,  7 , and  8 . In the preferred embodiment, as best shown in FIGS. 4 and 5, the lifting device  28  is rotatable member or steel rod  32 . The rod  32  is positioned in the bath  20  using lower wall opening  88 , upper wall opening  90 , washer  92 , and rotatable member seal  93 . The seal  93  is preferably fabricated from an elastomer, such as rubber. The rotatable member  32  preferably extends from upper wall opening  90  and through lower wall opening  88 . Upper wall opening  90  is located above lower wall opening  88  such that rotatable member  32  is positioned at angle  0  with respect to the bottom  24 E of bath  20 . Washer  92  is positioned in bath wall  24 D such that washer  92  aides the rotation of rotatable member  32  relative to wall opening  90 . Rotatable member seal  93  sealing opening  88  provides a water tight seal about rotatable member  32 . Since seal  93  surrounds cylindrical rod  32 , the rotation of rod  32  about its cylindrical axis does not significantly distort the seal  93 . Thus, the seal  93  is maintained under constant static pressure which is an advantageous condition for maintaining a good seal. Other embodiments may use upper wall rod  82  as the lifting device and in doing so may alleviate the need for seal  93  by locating the lowest wall opening above the water line of the bath. Leverage mechanism, generally indicated at  98 , attaches to the portion of rotatable member  32  which extends though lower wall opening  88  to provide lifting device  28  its lifting force. Yet, other embodiments may use entirely different lifting devices, including such mechanisms which are not connected with the guiding assembly, or such mechanisms which require no proposed openings in bath walls  24 , as discussed below in alternative embodiment A. 
     A preferred lifting power system  30  is best shown in FIGS. 6 and 7. The lifting power system  30  has the following four components: a fluid control system, generally indicated at  94 , a drive system, generally indicated at  96 , a leverage system, generally indicated at  98 , and a return mechanism, generally indicated at  168 . The fluid control system  94  controls the in-flow and the out-flow of fluid, such as liquid, into the drive system  96  and, therefore, controls the lifting and raising of the seat  22 . The drive system  96  transforms the fluid pressure into a mechanical linear force. The leverage system  98  transforms mechanical linear force into a torquing force applied to rotatable member  32 . The return mechanism  168  supplies a force to lower seat  22  to its lowered position. In the preferred embodiment, the lifting power system  30  is located out of view, within the walls of bath  20 . For easy access to the components of lifting power system  30 , a removable outer panel  25 , as best shown in FIGS. 4 and 5, is preferably incorporated into the bath  20 . Other embodiments may place the lifting power system within the adjacent bathroom walls, or, if necessary, even expose such a system in the bathroom itself. Other alternative embodiments may even use other forms of lifting power systems that provide torque to rotatable member  32 , for example, an electric motor. 
     As best shown in FIGS. 6 and 7, the fluid control system  94  of the preferred embodiment is made up of the following components: a feeder pipe  100 , a control valve  102 , a discharge pipe  104 , a control knob  106 , a needle valve  180 , a needle valve adjustment mechanism  182 , and a control pipe  108  between needle valve  180  and a chamber inlet  110 . Feeder pipe  100  communicates fluid which lifts seat  22 . The preferred embodiment, the fluid used is preferably water supplied under standard tap water pressure. However, it is contemplated that the fluid could be pressurized by a pump. Other alternative embodiments may use other forms of fluid control systems that control the flow of fluid into and out of fluid control system  94  or the drive system  96 . Also, it is contemplated that other embodiments may utilize other fluids other than water, such as other liquids or even gaseous materials in place of tap water. 
     Control valve  102  controls the flow of fluid between feeder pipe  100  and control pipe  108 . Control knob  106  operates control valve  102  to allow fluid to enter into, and exit from, the drive system  96  which, in turn, raises and lowers seat  22 . Control pipe  108  communicates fluid into and out of drive system  96 . Discharge pipe  104  empties fluid from drive system  96  into bath  20  by moving the control knob  106  so the control valve  102  is in the discharge position, as shown in FIG.  6 . It is contemplated that the fluid control system  94  would be initially adjusted through the manipulation of needle valve adjustment mechanism  182 , such that when control valve  102  is fully open the restricted setting of needle valve  180  would result in the bather descending at a comfortable rate of speed. It should be noted that control knob  106  can be moved such that control valve  102  is in misalignment with feeder pipe  100  and control pipe  108  allowing the operator to further control the volume of fluid entering or exiting pipe  108 , and as a result, control the speed at which seat  22  rises or lowers. FIG. 7 shows control valve  102  in the lifting power position, where seat  22  would rise at its fastest rate. The diameter of control valve  102 , feeder pipe  100 , and/or control pipe  108 , should be sized that the resulting seat movement moves at rate that is within a comfort level for bathers. 
     As best shown in FIGS. 6 and 7, drive system  96  comprises a chamber housing  111 , a chamber  112 , a piston rod  114 , a piston head  116 , a rod seal  118 , a rod connector  120 , a chamber housing mount  122 , and a piston head seal  124 . Chamber housing  111  defines chamber  112 . Chamber  112  is filled and emptied of fluid from the fluid control system  94  causing piston head  116  to travel within chamber  112 . Piston head  116  and piston head seal  124  provide a seal between the filled and unfilled portion of chamber  112 . Chamber housing  111  is secured to bath  20  via chamber housing mount  122 . Piston rod  114  is connected to piston head  116  and moves linearly with the movement of piston head  116 . Rod seal  118  provides a seal about the piston rod  114  at the exit point of chamber  112 . Rod connector  120  connects the piston rod  114  to the leverage system  98 . In the preferred embodiment, as beat shown in FIG. 6, the travel distance B of piston head  116  is greater than the distance A traveled by seat  22 , thus giving a leverage advantage to drive system  96  over seat  22 . Other alternative embodiments are contemplated that may use other forms of drive systems to transform fluid pressure into mechanical energy. 
     Continuing with FIGS. 6 and 7, the leverage system  98  of the preferred embodiment comprises a pulley assembly  126 , cam  128 , cam cable  130 , and cam cable connection  132 . Pulley assembly  126  comprises a pulley wheel cable  134 , pulley wheel  136 , pulley wheel post  138 , pulley body  140 , pulley body cable connection  142 , pulley wheel cable anchor  144 , and anchor connection  146 . Pulley wheel cable  134  is connected between rod connector  120  at the end of piston rod  114 , and anchor connector  146  located on pulley wheel cable anchor  144 . Pulley wheel cable  134  is looped about pulley wheel  136 . Pulley wheel  136  is rotatably attached to pulley body  140  on pulley wheel post  138 . Cam cable  130  is attached between pulley body  140  at the pulley body cable connection  142 , and cam  128  at cam cable connection  132 . Since cam  128  is fixedly attached about rotatable member  32 , any movement of cam cable  130  results in the rotation of cam  128  which, in turn, rotates rotatable member  32  to move seat  22 . Other alternative embodiments may utilize upper wall rod  82  as the rotatable member, with upper wall rod  82  only spanning between the wall connections and not extend into the side walls of the tub, and thus avoiding the need for any sealing means associated with opening  88  in the preferred embodiment since the upper wall rod is accessible above the water line of the bath. Yet, other alternative embodiments may use other forms of leverage systems which transform a supplied mechanical energy into rotational energy. 
     Still continuing with FIGS. 6 and 7, the return mechanism  168  of the preferred embodiment comprises a return cam  170 , a spring  172 , a return cam cable  174 , a return cam cable connection  176 , and a spring mooring  178 . Spring  172  is connected at one end to spring mooring  178 , and at the other, to return cam cable  174 . Return cam cable  174  is, in turn, connected to return cam cable connection  176 . Since return cam  170  is fixedly attached about rotatable member  32 , any movement of return cam cable  174  results in the rotation of return cam  170  which, in turn, rotates rotatable member  32  to move seat  22 . Other alternative embodiments may use other configurations to supply the force needed to return seat  22  to its lowered position, for example, a weight attached to seat  22 , such that gravitational force provides the force necessary to lower the seat, or a torsional spring attached to rotatable member  32 , such that rotational force urges the seat in the lowering direction. In addition, alternative embodiments may use springs of different sizes and strength or may use cams with a different radius. Yet, other alternative embodiments may utilize a single cam to perform both the functions of cam  128  and return cam  170 . 
     USE AND OPERATION OF PREFERRED EMBODIMENT 
     A typical bather, being wheelchair assisted, would typically leave the bath system with seat  22  in its lowered position, as shown in FIG.  1 . To transfer to the bath  20 , bather wheels their chair along side of bath  20 . The operator of the bath system then uses control knob  106  to initiate the flow of water from feeder pipe  100  through control pipe  108  into chamber  112 . As water fills chamber  112 , the water pressure forces piston head  116  along chamber  112  towards the bath wall  24 C. 
     As shown in FIGS. 6 and 7, as piston head  116  travels along chamber  112 , piston rod  114  and pulley wheel cable  134  move. Since pulley wheel cable  134  is threaded through pulley wheel  136  and anchored by pulley wheel cable anchor  144 , the movement of pulley wheel cable  134  causes pulley wheel  136  to rotate and move in the same direction. The use of this leverage system  98  requires less force from the drive system  96  to lift seat  22 . The movement of cam cable  130  causes cam  128 , return cam  170 , fixedly attached to rotatable member  32  to rotate. Return mechanism  168  is also set into motion with the movement of cam cable  130 , however, its operation is essentially inconsequential while seat  22  is occupied with a bather, as the force supplied by return mechanism  168  is small in comparison to the weight of the bather. As shown in FIGS. 4 and 5, as rotatable member  32  rotates, guiding assembly  26 , moves seat  22  in a smooth fashion along a straight line path from its central location at or near the longitudinal axis D of the bath bottom  24 E, as best shown in FIG. 3, to a location, as best shown in FIG. 5, where the side of seat  22  is at or beyond the top of side wall  24 D. The angle Ø of the path is preferably between 10° and 20° from the orthogonal of the bath bottom  24 E. Preferably Ø is 15°. In so moving, the arm sets  34 A,  34 B and  80 A,  80 B of guiding assembly  26  move in unison from a position pointing substantially towards the bottom  24 E of bath  20  to a position pointing substantially away from the bottom  24 E of bath  20  to raise connected seat bottom  22 A above the top of bath  20 . 
     In it fully raised position, seat  22  is at or beyond the top of the side wall  24 D of bath  20 , so that bather can transfer to seat  22 . To transfer to seat  22 , the bather maneuvers his or her wheelchair so that it is substantially parallel to the bath and next to the seat  22 . The bather then slides off the chair onto the ledge of bath  20  and/or, if capable, directly onto seat  22 . Then, the bather brings the bather&#39;s legs over side wall  24 D and into bath  20 . 
     As best shown in FIGS. 4,  5  and  6 , and discussed above, once securely in seat  22 , control knob  106  is operated to release the water from chamber  112  and lower the bather into bath  20 . The discharged water travels through control pipe  108  and discharge pipe  104  into bath  20 . D ig this process, seat  22 , guiding assembly  26 , lifting device  28 , and lifting power system  30 , all reverse direction. During the lowering mode, the bather sitting on the seat  22  experiences a constant and smooth descent along a straight line path away from the side  24 D of bath  20 , towards the central position longitudinal axis D of the bath bottom  24 E. When seat  22  has been properly lowered, the bather can begin bathing. The filling of the bath with bath water may be done at any point before, during or after this process, or, if a shower is desired, may not be filled at all. If the seat  22  is used in conjunction with a shower, the seat may be stopped in any desired position along the path that seat  22  travels. Allowing the operator to choose to stop seat  22  in any location along the path of seat  22 , the bather can choose the most comfortable position. For example, the bather may want the seat slightly elevated while taking a shower as compared to the lowest position to be more fully submerged while taking a bath. To stop the seat in any position along the path traveled by seat  22 , the operator need only position control knob  106  such that control valve  102  is in a position that it does not communicate control pipe  108  to either discharge pipe  104  or feeder pipe  100 . 
     To allow the bather to exit bath  20 , the operator simply follows the steps describing earlier to position the seat for transfer. However, now the operator operates the control knob  106  while the bather is in seat  22 . The operator and bather can be different or the same person. While exiting bath  20 , seat  22  ascends smoothly, in one continuous straight line movement, along a proportional angular path, from the lowered position at or near the longitudinal axis D of the bath bottom  24 E, to a raised position at or above the side of bath  20 . Once fully raised, the bather reverses his/her earlier movements to transfer back into the wheelchair. Once in the chair, the operator would use control knob  106  to return the seat  22  to its lowered position. To lower the unoccupied seat  22 , the operator simply follows the steps described earlier for lowering the seat. However, with the absence of a bather from seat  22 , the additional force generated by return mechanism  168  assist the return of seat  22 , guiding assembly  26 , lifting device  28 , and lifting power system  30  to their respective positions when seat  22  is in its fully lowered position. 
     Rotation assembly  40  allows for the rotation of seat  22  at a location above the top of bath  20 . The operation of is mechanism has not been described, but may be usefull for bathers. It is contemplated that bathers, not in wheelchairs, could mount the seat  22  when rotated to face the side of the bath, as shown in phantom view in  5 FIGS. 3 and 5. 
     ALTERNATIVE EMBODIMENT A 
     Turning now to the alternative embodiment A shown in FIGS. 10-11, the alternative embodiment A utilizes similar component parts to the preferred embodiment, including bath  20 , seat  22  and guiding assembly, but includes an alternative bellows member  148 . The bellows member  148  includes an upper connector ring  150 , a lower connector ring  152 , a bellows casing  154 , and a bellows inlet member  156 . This alternative embodiment includes the additional feature of bellows recess  158  in the bath bottom  24 E. The bellows recess  158  provides adequate space below the seat when the bellows is in its compressed mode. The presence of tbellows recess  158  may require a deeper channel recess  38  communicating between bellows recess  158  and the drain opening  24 F, or alternatively another drain opening could be provided in bellows recess  158 . Other embodiments may use a different recess formation or may have no recess formations at all. 
     Bellows casing  154  is attached between the seat bottom  22 A and the bottom  24 E of bath  20  via upper ring  150  and lower ring  152 . The lower ring  152  is located within bellows recess  158 . Bellows inlet member  156  allows for fluid to move between the fluid control system  94  including the needle valve  180  (not shown in FIGS.  10  and  11 ), as previously described, and bellows member  148 . As the bellows member  148  fills with a fluid, the bellows member  148  expands and raises seat  22 . Guiding assembly  26  controls the direction that seat  22  moves, as movement is imparted to seat  22  by expanding bellows member  148 . Here, unlike the preferred embodiment, rotatable member  32  ig a passive rotatable member, that does not need to extend through any bath wall, like the other above-described guiding assembly rods  82 ,  84  and  86 . With this exception, the guiding assembly, in this alternative embodiment, is essentially the same as the one in the preferred embodiment. Other embodiments may use other guiding assemblies, such as, the use of a simple guide pole or poles that extend from the walls of the bath. Such a pole might be disposed within the bellows member  148  itself. Other embodiments may follow a path other than the described angular path, for example, the seat may rise at a 90° angle to the bottom  24 E and, therefore, not have any lateral movement. Other embodiments may also place the bellows member  148  in a location other than below seat  22 . For example, the bellows may instead contact a guiding assembly connected to the seat, which, in turn, causes seat  22  to move. In addition, other embodiments may use other forms of an expandable member, which when expanded, causes the raising of seat  22 , for example, a balloon type member. 
     USE AND OPERATION OF ALTERNATIVE EMBODIMENT A; 
     The bather mounts and dismounts seat  22  in the same manner as described in the preferred embodiment. However, as best shown in FIGS. 10 and 11 to raise seat  22 , an operator uses control knob  106  to initiate the flow of fluid, such as water, from feeder pipe  100  through control pipe  108  into alternative bellows member  148 . As water fills bellows member  148 , the water pressure expands bellows member  148 . 
     As bellows member  148  expands, it pushes against seat  22  and moves seat  22  away from the bottom  24 E of bath  20 . Guiding assembly  26  guides seat  22  along a smooth and continuous straight line proportional angular path from the longitudinal axis D of bath bottom  24 E, to a location where the side of seat  22  is at or beyond the top of side wall  24 D. In so moving, the set of arms  34 A,  34 B and  80 A,  80 B of guiding assembly  26  move in unison from a position pointing substantially towards the bottom of bath  20  to a position pointing substantially away from the bottom  24 E of bath  20 , and raise seat bottom  22 A above the top of bath  20 . 
     To lower seat  22 , the operator moves control knob  106  to release water from bellows member  148  to discharge pipe  104  into the bath. The weighted seat  22 , or, in case a bather is located thereon, the weight of a bather and the seat, on bellows member  148  urges the water within bellows member  149  to be discharged into control pipe  108 , through control valve  102  to discharge pipe  104  into bath  20 . During the lowering mode, seat  22  experiences a constant and smooth straight line decent along a proportional angular path away from the side  24 D of bath  20 , towards at or near the longitudinal axis D of the bath bottom  24 E. 
     ALTERNATIVE EMBODIMENT B 
     Turning now to the alternative embodiment B shown in FIG. 12, the alternative embodiment B utilizes similar component parts as those found in the preferred embodiment except that lifting power system  30  is significantly altered. Although the fluid control system  94  and the return mechanism  168  have remained very similar to those in the preferred embodiment, the drive system  96  and the leverage mechanism  98  of the preferred embodiment have been replaced with a lifting power system comprising a power piston system  184  and power cam system  186 , respectively. 
     The power piston system  184  comprises a power piston housing  188 , a power piston chamber  190 , a power piston rod  192 , a power piston head  194 , a power piston rod seal  196 , a power piston rod connector  198 , a power piston housing mount  200 , and a power piston head seal  202 . A power piston housing  188  defines power piston chamber  190 . Power piston chamber  190  is filled and emptied of fluid from the fluid control system  94 , tough power inlet member  210 , causing power piston head  194  to travel within power piston chamber  190 . Power piston head  194  and power piston head seal  202  provide a seal between the filled and unfilled portion of power piston chamber  190 . Power piston chamber  190  is secured to bath  20  via power piston housing mount  200 . Power piston rod  192  is connected to power piston head  194  and moves linearly with the movement of power piston head  194 . Power piston rod seal  196  provides a seal about the power piston rod  192  at the exit point of power piston chamber  190 . Power piston rod connector  198  connects power piston rod  192  directly to the cam system  186  via power cam cable  204 . 
     USE AND OPERATION OF ALTERNATIVE EMBODIMENT B 
     The operation of alternative embodiment B is similar to that of the preferred embodiment. However, power cam cable  204  is instead connected directly between power piston rod connector  198  and power cam connector  206 , eliminating pulley assembly  126  of the preferred embodiment. Rather than using a pulley assembly  126  to provide leverage to the force supplied by power piston system  184 , power cam cable  204  provides a direct connection between power piston system  184  and power cam system  186 . As shown in FIG. 12, as power piston head  194  travels along power piston chamber  190 , power piston rod  192  and power cam cable  204  move along a linear path. The movement of power cam cable  204  causes both power cam  208  and fixedly attached rotatable member  32  to rotate. This rotation, as described in the preferred embodiment, results in the lifting movement of seat  22 . 
     The foregoing disclosure and description are illustrative and explanatory thereof, and various changes in the size, shape, and materials, as well as in the details of illustrative construction and assembly, may be made without departing from the spirit of the invention.