Patent Publication Number: US-10314440-B2

Title: Bathtub with door and drain

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a National Entry Application of PCT application No. PCT/CA2017/050658 filed on May 30, 2017 and published in English under PCT Article 21(2), which itself claims priority to U.S. provisional Patent application Ser. No. 62/343,241 filed on May 31, 2016. All documents above are incorporated herein in their entirety by reference. 
    
    
     TECHNICAL FIELD 
     The present application relates to a bathtub with a slide-down door for easy access by individuals. In particular, the present invention relates to a bathtub that provides an easy access, especially for older people that have lesser autonomy, reduced mobility or who require help for taking a bath. 
     BACKGROUND 
     Several models of relatively accessible bathtubs exist in the market, mostly with an access threshold that is lowered with respect to the ground. However, what exists in the market is suitable only for a short period of use. Indeed, such bathtubs do not adapt well with the physical degeneration of the user&#39;s age (loss of independence, need of a walker, need of a wheelchair) and become practically unusable if bathing assistance becomes necessary. In addition, people with lessening autonomy often feel embarrassed when visitors or other users of the bathroom see such a bathtub due to its appearance that is reminiscent of hospital furniture. 
     Other bathtub models are better suited for people who need a walker or wheelchair or are disabled or the like. Those known bathtubs use a side door and a raised seat, but still have numerous drawbacks. For example, those known bathtubs require electricity when the bather needs to get out of the bath, so that if a power blackout occurs, these are rendered inoperative. Also, such bathtubs require a long period of time for emptying the tub. Some of the existing bathtubs have a poor design that can increase the risk of back pain for caregivers that assist the bather. Also, installing these bathtubs requires significant changes to the existing plumbing of the facility. In addition, this creates a relatively small space for future maintenance of the drain, since these are installed under the existing drain. Moreover, many of these bathtubs have replaced manual sealing with pneumatic sealing systems, to reduce the effort required by the user, such as by using compressors, which besides being very expensive, are also very noisy and run against the principle of a relaxing bath. 
     Also known are the following patent documents: 
     U.S. Pat. Nos. 5,163,187 and 5,220,696 (Dannenberg et al.) assigned to Kohler Co., disclose a bathtub with a vertical axis hinged door and an inflatable seal. 
     US Patent Publication No. 2007067901 and U.S. Pat. No. 7,237,276 (Longman), disclose a bathtub with door movable along a horizontal direction between open and closed positions. 
     US Patent Publication Nos. 2011167555 and 2012198611 (Zierler et al.), assigned to Artweger GMBH &amp; Co., disclose a closing and securing assembly for a bathtub with a water-tight door. 
     WO2013125477 (Torii et al.), assigned to Sakai Medical Co., discloses lift mechanism for a bathtub with a support for a sitting section and a lift drive section which vertically moves the sitting section along the support. 
     WO2015198280 (Polo Filisan), assigned to Jacuzzi Europe SPA, discloses a bathtub with a door movable between open and closed positions. The door includes two panels that are hinged together. 
     U.S. Pat. Nos. 8,230,534; 9,254,066 (Torres et al.) assigned to Aquatic Co.; assigned to Kohler Co., disclose an accessible bathtub with a slide-down door that allegedly provides quick bathtub draining to minimize chilling of the bather. Indeed, a problem with known prior bathtubs is that the person inside such bathtub generally cannot leave the tub after bathing until the tub has fully drained and the door is then opened. As mentioned above, conventional tub draining systems take too long to drain, resulting in a chilling experience for the bather. 
     U.S. Pat. No. 8,863,323 and Patent publication No. 2015020305 (Knapp et al.) assigned to Kohler Co, discloses a bathtub with a door movable between lowered and raised positions, door position sensors for sensing the position of the door, and a controller in electronic communication with the position sensors for controlling components of the bathtub based on the position of the door. 
     SUMMARY 
     According to the present invention, there is provided a bathtub comprising a tub having an enclosure defined by at least one sidewall for holding a water capacity, a doorway on the sidewall for providing access to the tub, a door mountable onto the doorway for holding at least two water levels in the tub, an actuator for moving the door over the doorway allowing a user to move the door between at least three positions including a lowered, an intermediate and elevated positions, a mechanical drain for emptying the tub, a double reservoir for receiving water from the tub through the drain and a door drip, a control interface, door position sensors for detecting intermediate and elevated locking positions of the door, water detection sensors for detecting the water level in the tub and reservoir, a pressure sensor for detecting a pressure in a seal valve of the door, and a controller configured to receive input controls signals from the control interface for security control, receive input door lock position signals from the door position sensors, receive input water detection signals from the water detector sensor, receive input pressure signals from the pressure sensor for sealing the door, send control signals to control a sealing valve of the door, and send control signals for operating a drain valve. 
     In embodiments, a bathtub according to the present invention addresses the above drawbacks by incorporating innovative solutions and a modern design. 
     In embodiments, the bathtub has a side opening for receiving a slidable door that is movable at least between lowered and raised positions, and also at least to an intermediate position. The bathtub may include a raised seat. 
     In embodiments, the bathtub comprises walls defining a contour, in which at least a portion of one or more vertical walls is provided with a door. The bath may be made of a shell which defines an entrance on a portion thereof or on all of one or more vertical walls of the shell. 
     In embodiments, the bathtub may include at least one door for retaining water in one of its multilevel closed positions, and to provide free passage in its open position. 
     In embodiments, the door leaves a passage for a bather when in an open position or is closed or partially closed in its various closed levels. 
     In embodiments, the door has an integrated overflow system allowing the bathtub to meet safety standards and prevent spills regardless of the chosen door position. 
     In embodiments, the door can be moved in multiple positions, such as a middle position, which helps with bathing an incapacitated person, or washing a child, and in the highest position to contain a maximum water level to allow full relaxation of the bather. 
     In embodiments, the door, which can be moved to multiple positions, is provided with a frame allowing it to withstand the pressure of different sealing levels. 
     In embodiments, the door makes a movement from bottom to top in a circular direction, but it could also be a linear direction, an elliptical direction, or a combination of those movements. The inertia of the door due to its weight may be countered or alleviated for the user by means of an assisting device such as a gas cylinder and/or spring. The door could also be motorized with an actuator, a solenoid, a set of counterweights, or other known means for providing a straight linear movement and/or circular movement. 
     In embodiments, the bathtub includes a controller for managing the automation, safety devices, and an optional user keyboard. 
     In embodiments, the controller performs a bath sequence analysis of the various states of the system to control both the water supply and the cap closure of the drain. 
     In embodiments, the controller cuts off the water supply if water is detected in the drain reservoir so as to avoid an overflow of the bathtub. 
     In embodiments, the bathtub includes an automatic drain that is controlled by the controller. 
     In embodiments, the controller enables the water supply if the door is opened to permit cleaning of the bath and/or test the water temperature before filling the tub. 
     In embodiments, the controller allows the closure of the drain hole if the position of the door is not open, if the pressure required for the sealing is attained and maintained, and if the drain tank is detected as empty. 
     In embodiments, the automatic drain includes a cylinder for lifting a movable plate acting as a plug when it abuts against the drain hole to close the passage of water. 
     In embodiments, the drain can be operated with water, air or any gas or liquid, while achieve the same result. 
     In embodiments, the controller has an integrated power pack to allow a delay and for a user to safely get out of the bath, without the disagreement of an automatic open drain in the case of a rapid failure. 
     In embodiments, the drain could also be used for different door bathtub models, either hinged, counterweight, side slide, or double-axis as well as for conventional baths. 
     In embodiments, the drain function may also be operated by means of a flexible membrane assembly or a diaphragm, a lifting cushion, or any other similar actuator or lever. 
     In embodiments, the drain is installed in the same shell of the bathtub but may be installed outside the shell. 
     In embodiments, the drain is designed so as to be removably installed. The drain can be removed entirely from the interior of the tub by a plumber so as to allow for checking or maintenance of the drain or of the reservoir. 
     In embodiments, the drain has a round outlet in order to facilitate the molding of the shell, but could be of any shape without affecting the performance. 
     In embodiments, the drain has a hair filter to reduce the risks of the reservoir becoming blocked or clogged and to reduce its maintenance. 
     In embodiments, the tub has a drain cover for masking the non-aesthetic portion of the drain, to protect the user from the risk of being pinched by the automatic drain, to distribute the water removal in a way that diminishes swirls and noises and to control the draining speed. 
     In embodiments, the bathtub includes a buffer zone or reservoir for fast draining and/or rapid filling. 
     In embodiments, the reservoir allows for draining the tub in less than 30 seconds, eliminating the cooling and discomfort felt by the user in the bathtub, since the user must wait a full or partial drainage (in some type of bath doors) to get out of the bathtub. 
     In embodiments, the reservoir allows for draining the tub in less than 30 seconds, even if the tub has its highest volume of water possible with no bather in the tub and filled to the overflow. 
     In embodiments, the bathtub includes a retaining system of the draining mechanism for retaining the drain inside the shell. 
     In embodiments, the retaining system of the drain mechanism is designed to allow a watertight installation, without silicone, despite different process variations. 
     In embodiments, the retaining system of the drain mechanism allows it to be easily installed and removed to permit maintenance or a simplified replacement. 
     In embodiments, the retaining system of the drain mechanism includes fixing rods which move vertically by the clamping of holding bolts. When tightened, the holding bolts lift the fixing rods, which enter into contact with the structure of the bath, the drainage mechanism is then clamped in its position. 
     In embodiments, the bathtub includes a rapid drain system based on a concept that has long existed in the prior art, such as in DE 3508713 (Hawliczek). The rapid drain system uses a buffer reservoir, but which has been modified to provide an easy access to the drain through a removable drain that may be quickly removed from the inside of the bathtub. Maintenance service costs are very expensive for existing bathtubs of this type. However, by incorporating a fully removable drain installed inside the bathtub and provided with an attachment mechanism that does not require access under the bath like that of typical bathtubs, service costs can be reduced substantially by installing a simple access to the main drain. Once removed, the drain mechanism allows quick replacement in case of malfunction and/or gives way to an opening giving access to the buffer reservoir to a plumber. 
     In embodiments, the drain is an automatic drain comprising a cylinder for raising a movable plate acting as a cap that closes an opening to prevent passage of water. 
     In embodiments, the door, unlike others on the market, may be set to at least three positions: open, closed and intermediate or mid-height. An overflow is built into the door so as to always be at a height that is compliant to the industry standards and different plumbing codes. The mid-height of the door provides caregivers a more ergonomic bath when assisting the bather. This mid-height position makes it even possible for a caregiver to be sitting when assisting the bather. 
     In embodiments, the door is sealed with an expandable seal with textile reinforcement to act as a stop for the door. This design is based in prior art U.S. Pat. No. 3,042,980 (Brinsmade). Such seal is unlike the non-reinforced seal, which is frequently used in the bathroom market such as in U.S. Pat. No. 5,163,187 (Dannenberg et al.). Because at mid-height the upper seal does not contact the door, the textile reinforcement is used to limit the expansion thereof, and thereby avoiding premature wear of the seal. 
     In embodiments, the bathtub does not require a compressor, but rather uses the water pressure of the residential circuit. This allows to both seal the door and automatically close the drain. A pressure regulator on the line lowers the pressure to ensure a predetermined fixed pressure and reduces the risk of problems in places with high pressure networks. The actuator cap is connected to a normally closed supply valve and normally open drain valve allowing to cut the water supply and to perform drainage in case of power failure. Accordingly, water in the tub is drained automatically in case of power failure. 
     In embodiments, the double reservoir comprises a single discharge port. 
     In embodiments, the single discharge port comprises a non-return device preventing the return of water to the door drip. 
     In embodiments, the controller has several bath conditional protection devices, making it relatively safer compared to bathtubs in the market. The controller allows sealing of the cap if the pressure is not reached in the door sealing system and the water supply is cut if water is present in the reservoir, which prevents a possible overflow in case of blockage of the external drain system. In known bathtubs available in the market, the following sequence is often times observed: first the door is closed, then second, after a predetermined time period, the cap is closed. However, without the first step of closing being conditional upon the second step of closing the cap, problems may arise in case of a component malfunction. Moreover, in general the water supply is usually not controlled in the bathtubs that are currently available on the market. 
     In embodiments, the followings steps are followed:
         the bather sits in the bath or executes a transfer from a wheelchair to the tub;   the bather operates the handle to unlock the door;   the bather controls the lifting of the door to the desired height and releases the handle;   the spring return mechanism locks the door;   the bather presses on a door sealing command;   the door is sealed;   a pressure sensor validates that the door is well sealed;   a water level sensor of the reservoir and drain validates that the reservoir is empty;   the controller closes the tub plug;   the controller lets water pass from the filling source;   the bather can operate the filling, or the controller fills the tub with water having a predetermined temperature;   the bather stops the water to the desired level, or the controller stops the filling source to a predetermined level;   the bather activates the drain by pressing and maintaining the sealing button for about three seconds (the three second time period is to avoid unwanted or accidental drainage);   the controller operates the drain opening;   the tub is emptied into the drain and reservoir in less than 30 seconds;   a water level sensor detects that the tub is empty;   the controller unseals the door;   the bather operates the handle to unlock the door;   the bather lowers the door and releases the handle;   the spring return mechanism locks the door in the open position; and   the bather can get off the tub and get up or execute a transfer to a wheelchair.       

     In embodiments, the following control sequence is followed:
         the control button is held by the user or bather;   the controller checks the position of the door and whether there is water detected in the bath or in the tank;   if a desired condition is not achieved, the LED indicator blinks for 30 seconds or an error code is shown on the digital keyboard;   if the door is open and no water was detected:   the door is brought to the desired height and the handle is released by the bather;   the lock position switch is activated;   the sealing control button is activated by the bather;   the controller activates the sealing valve;   the pressure sensor validates that the door is properly sealed;   the controller closes the drain valve and opens the filling valve;   the controller lets water pass from the filling source;   the bather can operate the filling, or the controller fills the bath with water at a predetermined temperature;   the bather stops the water to the desired level, or the controller shuts down the filling source to a predetermined level by the user;   the water level in the tub is detected;   the sealing button is held for three seconds (to avoid unwanted or accidental drain);   the controller activates the opening of the cap of the drain valve;   the tub empties into the reservoir in less than 30 seconds;   detects the water level in the reservoir;   detects the absence of water in the tub;   the controller activates the opening of the drain valves;   the sensor alerts the controller that the bath is empty;   the controller unseals the door;   the bather operates the handle to unlock the door;   the bather lowers the door and releases the handle;   the spring return mechanism locks the door in its lowest position;   the bather can get off the tub and get up or execute a transfer to a wheelchair.       

     In embodiments, a status light is illuminated when proper sealing of the door is achieved. When a problem is detected, the status light may blink, or an error code may be displayed on the digital keyboard. 
     In embodiments, when the pressure sensor detects that a pressure limit is reached, it sends the information to the controller to indicate that the safety step has been reached (it could be used as a switch on the supply valve to reduce the number of “INPUTS” of the controller if single valves are use); 
     In embodiments, the drain valve for sealing the door can be only two 3-way valves or four single valves if the two actions of the actuator are controlled, or one 3-way valve or two single valves if a spring return actuator is used or for all other custom assembling valves. 
     In embodiments, the mechanical drain comprises a drain actuator that comprises two valves for controlling the opening and closing of the drain. 
     In embodiments, the input water valve can be automatically closed to prevent damage if water is detected in the reservoir. The water valve may close the tap water supply or any other device used to fill the tub. 
     According to the present invention, there is also provided a mechanical drain for a bathtub, comprising a drain actuator for opening and closing a drain plug on a drain plate, the drain plate being fixable in draining enclosures by means of a retention bracket, a compressed gasket sealing between draining enclosures and the drain plate. In embodiments, the drain actuator comprises two valves, the valves controlling the opening and closing of the drain. 
     In embodiments, the retention bracket is movable up and down by tightening mounting bolts and adapted to be maintained parallel by means of a guide rod. In embodiments, the mechanical drain comprises a drain cover. In embodiments, the mechanical drain comprises a hair filter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The various embodiments disclosed here in will be better understood by way of the following detailed description with reference to the appended drawings, in which: 
         FIG. 1  is a perspective schematic view of a bathtub according to a preferred embodiment of the present invention, showing its door open; 
         FIG. 2  is another schematic perspective view of the bath shown in  FIG. 1 , showing the door closed; 
         FIG. 3  is another schematic perspective view of the bath shown in  FIG. 1 , showing the door at mid-height; 
         FIG. 4  is a side view schematic view of the bathtub shown in  FIG. 1 ; 
         FIG. 5  is a sectional view of a drain in the closed position, used in the bath shown in  FIG. 1 , according to a preferred embodiment of the present invention; 
         FIG. 6  is another schematic perspective view of the drain of  FIG. 5 , showing the drain in the opened position; 
         FIG. 7  is a top schematic view of the bathtub shown in  FIG. 1 ; 
         FIG. 8  is another schematic top view of the bathtub of  FIG. 7 , showing the drain without its drain cover; 
         FIG. 9  is another schematic top view of the bathtub of  FIG. 8 , showing the drain without the hair filter; 
         FIG. 10  is another schematic top view of the bathtub of  FIG. 9 , showing the drain without drain valve assembly; 
         FIG. 11  is a front elevation view of the bathtub shown in  FIG. 1 ; 
         FIG. 12  is a side schematic view of the bathtub shown in  FIG. 1 ; 
         FIG. 13  is a side schematic view of the structural frame of the bathtub shown in  FIG. 1 ; 
         FIG. 14  is a back perspective view of the bathtub shown in  FIG. 2 ; 
         FIG. 15  is another schematic perspective view of the bathtub shown in  FIG. 14 ; 
         FIG. 16  is another schematic back perspective view of the bathtub shown in  FIG. 15 , showing the door without finishing panel; 
         FIG. 17  is another schematic perspective view of the bathtub shown in  FIG. 15 , showing its door open; 
         FIG. 18  is another schematic perspective view of the bathtub shown in  FIG. 16 , showing the door at mid-height; 
         FIG. 19  is another schematic perspective view of the bathtub shown in  FIG. 1 , showing the bathtub with the door in an open position and finishing panels; 
         FIG. 20  is a front elevation view of a bathtub according to another preferred embodiment of the present invention, wherein the bathtub is empty of water and its door is in a lowered position; 
         FIG. 21  is a front elevation view of a bathtub according to another preferred embodiment of the present invention, wherein the bathtub is empty of water and its door is in an elevated position; 
         FIG. 22  is a front elevation view of a bathtub according to a preferred embodiment of the present invention, wherein the bathtub is empty of water and its door is in a mid-height position; 
         FIG. 23  is a schematic perspective view of the sewage segregation system of the double reservoir. 
         FIG. 24  is a schematic perspective view of the side of the door. 
         FIG. 25  is a top schematic view of the double reservoir. 
         FIG. 26  is a schematic view of a controller of a bathtub and different elements connected to the controller, according to a preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 to 26 , there is shown a bathtub  10  that includes a tub  12  having an enclosure defined by at least one sidewall  14  for holding a water capacity, according to different embodiments of the present invention. The bathtub  10  has a doorway  16  on the sidewall  14  for providing access to the tub  12 . A sealing strip  18  is installed on the periphery of a doorway  16 . A set of finishing panels  20  are positioned in the front of the bath  10 , and are used to mask the sealing strip  18 . A door  22  is mountable onto to the doorway  14  for holding at least one water level in the tub  12 . The bathtub  10  has a unidirectional double side door lock mechanism  24  for holding the door  22  over the doorway  16  between at least two positions, preferably at least three positions such as a lowered, an intermediate and elevated positions. A receiver door drip  36  is fixed under the door  22  and incorporated to the double reservoir  62 , to catch the water in the sealing strip  18  when the door  22  is in the lower position. The door  22  has a door frame  30  to support pressure of the sealing strip  18 . The door frame  30  is fixed to the door arms  28 , themselves fixed to the pivot axis  26 . The pivot axis  26  is fixed to removable structural pivot plates  66 , themselves fixed to the tub frame  64  and the gas cylinder  68 . The door has a unidirectional lock actioned by the lock rod  70 . The door  22  has a door overflow  32  using, for example, a structural overflow pipe. The door overflow  32  allows the door  22  to receive water therein and allows the door  22  to be maintained in any position of the door  22  as it moves up and down. The door overflow  32  function may be achieved in other different ways other than the illustrated structural pipe. Indeed, one may use a flexible tube or pipe or a slidable tube or pipe that follows the movement of the door  22  to achieve the function of the door overflow  32  to control the height of the water level in respect to door  22  heights at a desired level. Alternatively, one or more draining valves may be used to achieve the function of the door overflow  32  to control the height of the water level in respect to door  22  heights at a desired level. 
     The bathtub  10  also has a frame  64  to hold together the tub  12 , the door  22 , and the reservoir with double compartment  62 . The reservoir with double compartment  62  is equipped with a sewage segregation system  72  that prevents water from the reservoir to the receiver door drip  36 . In embodiments, other systems could be used, such as a mechanical trap or a check valve. The sewage segregation system  72  has a reservoir drain  74 , a tail piece  76 , a segregation pipe  78 , and a receiver drain  80 . 
     The bathtub  10  includes a mechanical drain, as best shown in  FIG. 5 , for emptying the tub  12 . The bathtub  10  may have a reservoir  62  for receiving water from the tub  12  through the hole of drain  38 . A tub  12  has a draining enclosure  60  and hole drain  38 . 
     Referring to  FIG. 5 , the draining enclosures  60  contain the mechanical drain. The mechanical drain has a drain actuator  48  for opening and closing the drain plug  44  on the drain plate  46 . The drain actuator  48  may have an integrated spring return, water activation on both sides or an external spring return, managed by the controller  92 . The drain plate  46  is fixed in the draining enclosures  60  by the retention bracket  56 , the compressed gasket  52  sealing between draining enclosures  60  and the drain plate  46 . The retention bracket  56  is movable up and down by tightening the mounting bolts  54  and maintained parallel by the guide rod  58 . The mechanical drain also has a drain cover  40  and a hair filter  42 . 
     Referring to  FIG. 26 , in addition to  FIGS. 1 to 25 , the bathtub  10  includes a door push button  84  used by a user or bather. Also shown are door position sensors  86  for detecting the lowered, intermediate and elevated positions of the door  22 . Also shown are water detection sensors  88  for detecting water level in the tub  12  and reservoir  62 . Also shown is a pressure sensor  90  for detecting a pressure in the door sealing strip  18 . Also shown is a controller  92  configured to: receive input controls signals from the door push button  84 ; receive input door position signals from the door position sensors  86 ; receive input water detection signals from the water detector sensor  88 ; receive input pressure signals from the pressure sensor  90  for sealing the door sealing strip  18 ; send control signals to control a sealing valve  94  of the sealing strip  18 , illustratively at different levels for sealing the door  22 ; and send control signals for operating a drain valve  96 . 
     The bathtub  10  may include a water supply valve  98  that is connected to the controller  92  for controlling water input into the tub  12 . The bathtub  10  may include a status light  100  that is connected to the controller  92  to display a status of the different systems. A keyboard  104  may also be connected to the controller  92 . 
     While the invention has been shown and described with reference to preferred embodiments thereof, it will be recognized by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.