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'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 & 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.