Abstract:
A combination of a tub surface heating device and a tub has a tub wall with an inner surface which is in contact with water, and an outer surface which stays dry during use of the tub. A heat source heats by conduction the inner surface of the tub wall. A securing configuration secures the heat source on the outer surface of the tub wall. A method for heating the tub wall is also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This patent application claims priority on U.S. Provisional Patent Application No. 60/631,417, filed on Nov. 30, 2004, by the present applicant. 
     
    
     TECHNICAL FIELD  
       [0002]     The present invention generally relates to tubs, such as bathtubs, bathing enclosures, spas, whirlpools and the like, and, more particularly, to a heating system used in conjunction with such tubs.  
       BACKGROUND ART  
       [0003]     Tubs are well known for their primary use, namely a washroom installation in which a user person washes and bathes. Tubs have however evolved to add pleasure and comfort to practicality, and are found in many forms, such as bathtubs, spas, whirlpools. For instance, tubs are now provided with air jet systems and whirlpool systems. There is an increasing variety of products, such as bathing oils, creams, lotions, that emphasize the therapeutic and health-beneficial aspects of bathing.  
         [0004]     One of the factors that is adjusted by bathers is the temperature of the fluid within the tub. Taking a hot bath has a soothing effect, while taking a cool bath can be refreshing. In some cases, however, there is a temperature variation between the walls of the tub and the fluid in the tub. For instance, the walls of the tub above the water line can often be cooler than the water.  
         [0005]     As bathers typically rest or lean against parts of the tub above the water line, the skin of the bathers contacting these surfaces transmit a feeling of discomfort to the bather.  
         [0006]     In order to warm up tub walls, some air ducts systems have been added about hidden surfaces of tub walls so as to heat the tub wall with warm air (i.e., by convection). However, such systems are bulky, and are inefficient in distributing heat to the tub walls uniformly. Moreover, as tubs are often equipped with other systems such as air massage systems, air ducts can not be used due to a lack of space about the hidden surface of the tub wall.  
       SUMMARY OF INVENTION  
       [0007]     Therefore, it is a feature of the present invention to provide a tub surface heating device to heat parts of walls of a tub.  
         [0008]     It is a further feature of the present invention to provide a tub surface heating device and method that addresses issues associated with the prior art.  
         [0009]     Therefore, in accordance with the present invention, there is provided a combination of a tub surface heating device and a tub, comprising a tub having a tub wall with an inner surface which is in contact with water and an outer surface which stays dry during the bath, a heat source which heats by conduction the inner surface of the tub wall, and a securing configuration, said configuration securing the heat source on the outer surface of the tub wall.  
         [0010]     Further in accordance with the present invention, there is provided a method for heating a tub wall having an inner surface which is in contact with water and an outer surface which stays dry during the bath, comprising securing a heat source to the outer surface of the tub wall; connecting said heat source to a power source; and actuating said heat source to heat the tub wall. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     A preferred embodiment of the present invention will now be described with reference to the accompanying drawings in which:  
         [0012]      FIG. 1  is a plan view of a tub surface heating device in accordance with a preferred embodiment of the present invention;  
         [0013]      FIG. 2  is a rear elevation view of the tub surface heating device of  FIG. 1 ;  
         [0014]      FIG. 3  is a side elevation view of the tub surface heating device of  FIG. 1 ;  
         [0015]      FIG. 4  is a perspective view of a heating system in accordance with a preferred embodiment of the present invention, as mounted to a tub;  
         [0016]      FIG. 5  is a sectional view showing an installation of the heating system to the tub; and  
         [0017]      FIG. 6  is a schematic view of a heating circuit of the heating device of  FIG. 1 . 
     
    
     DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0018]     Referring to the drawings and, more particularly, to  FIG. 4 , a tub surface heating system in accordance with a preferred embodiment of the present invention is generally shown at  10 . The heating system  10  is shown as positioned for use with a tub A, and is secured to the hidden surface B of the tub wall. It is pointed out that the expression “hidden surface” is used together with the expression “outer surface” to identify the surface of the tub that remains dry during a bath.  
         [0019]     The tub surface heating system  10  has tub surface heating devices  12 . In the embodiment illustrated in  FIG. 4 , the heating system  10  has three heating devices  12 , but may have one or more of the heating device  12 . The heating devices  12  are serially interconnected, and are connected to a controller  13  by wire  14 . The controller  13  is connected to a power supply by feed line  15 . A user interface  16  is provided on an exposed surface C of the tub A.  
         [0020]     Referring concurrently to FIGS.  1  to  3 , the tub surface heating device  12  is shown having a heating panel  20 . The heating panel  20  has a first surface  20 A and a second surface  20 B. An electric plug  21  is provided at an upper end of the panel  20  on the second surface  20 B, and is wired to a heating circuit  22  ( FIG. 6 ) within the panel  20 . An electric receptacle  23  is oriented away from the electric plug  21 , and is also wired to the heating circuit  22  ( FIG. 6 ). The heating circuit  22  generates heat that will be distributed by the heating panel  20  to the tub wall, so as to heat the tub wall. The electric plug  21  and the electric receptacle  23  both project laterally from wire connectors  24 , which protrude from the second surface  20 B of the heating panel  20 .  
         [0021]     The wire connectors  24  are sealingly connected to the second surface  20 B of the heating panel  20 , so as to isolate live wires therein. The assembly of the wire connectors  24  with the heating panel  20  is sturdy, so as to prevent exposure of the wires in the wire connectors  24 , and thus prevent electrical shocks or short circuits.  
         [0022]     In an embodiment, the heating panel  20  receives heat generated by an electric source, i.e., the heating circuit  22 . However, it is contemplated to provide other types of heating, such as heat-transfer fluid piping in the heating panel  20 .  
         [0023]     As seen in  FIGS. 4 and 5 , the heating panel  20  is secured to the tub A, with the first surface  20 A against the hidden surface B of the tub A by a securing configuration. The heating panel  20  is glued or attached to the hidden surface B of the tub A, as shown by glue surplus  25  at the edge of the heating panel  20 . Any other way of securing the panel  20  to the tub A is considered. For instance, the heating panel  20  may be integrally formed in the fiberglass reinforcement of the tub A, or mechanical fasteners can provide mechanical support to the heating panel  20 .  
         [0024]     The heating panel  20  is preferably made of a flexible material, so as to conform to the shape of the hidden surface B, and be in an optimized thermal coupling therewith. The material of the heating panel  20  must also transfer heat of the heating circuit  22  uniformly, while being capable of sustaining heat. For instance, the heating panel  20  has a layer of silicone hosting the heating circuit  22 , and defining the first surface  20 A of the panel  20 , so as to transmit uniformly heat from the heating circuit  22  to the tub wall.  
         [0025]     The heating panel  20  preferably has an insulating layer defining the second surface  20 B of the panel  20 , such that heat generated by the heating circuit  22  is mostly directed to the tub wall.  
         [0026]     The orientation of the electric plug  21  and the electric receptacle  23  is such that the heating device  12  is readily connectable in series with other heating devices  12 , for a single power feed. This is well illustrated in  FIG. 4 , in which three heating devices  10  are serially connected. It is also contemplated to connect the heating devices  12  independently to the controller  13 . The controller  13  may then control the heating devices  10  individually to produce different temperatures at different locations in the tub A.  
         [0027]     The preferred configuration of the heating device  12  and its electric plug  21  and receptacle  23  is such that when the heating devices  12  are serially connected, as in  FIG. 4 , there is a space between panels  20  of adjacent devices  12 . Therefore, overlapping arrangements of jets of air massage systems/whirlpool systems with the heating system  10  of the present invention, so as to provide multiple effects to the user of the tub.  
         [0028]     For instance, as shown in  FIG. 4 , a pair of pipes D having jets E of a massage system are shown positioned in spaces between adjacent pairs of heating devices  10 . Moreover, the tub surface heating system  10  in accordance with a preferred embodiment of the present invention may be installed on a tub already equipped with massage system piping because of the space between adjacent heating panels  20 .  
         [0029]     Referring to  FIG. 6 , the heating circuit  22  is schematically shown within the heating panel  20 , and with the electric plug  21  and the electric receptacle  23 . The heating circuit  22  has a heating element  30  (e.g., heating resistor, heater wires). The temperature of the heating panel  20  is regulated by way of a regulator  31  (e.g., thermostat). The regulator  31  is for instance a preset regulator adapted to maintain the temperature at a predetermined value. A knob (not shown) may be provided for the manual adjustment of the temperature setting.  
         [0030]     As an additional safety feature, a thermal fuse  32  is provided in the heating circuit  22 , to prevent overheating of the heating panel  20 . The thermal fuse  32  is adapted to break off at temperature above the temperature setting of the regulator  31  (ensuring that the heating shuts off to avoid burning the skin of the occupant of the tub A).  
         [0031]     A temperature sensor  33  may also be provided in the heating panel  20 . The temperature sensor  33  is wired to the controller  13  ( FIG. 4 ), so as to provide temperature readings to the controller  13 .  
         [0032]     Referring to  FIG. 4 , the electronic controller  13  is shown connected to the serially connected heating devices  12  by wire  14 . The controller  13  receives a power supply from the feed line  15 , and selectively transmits the feed to the heating devices  12 , according to commands from the user interface  16 . The user interface  16  has an on/off switch, such that the occupant of the bath may actuate the heating system  10  of the present invention.  
         [0033]     Additionally, the user interface  16  may be provided with a temperature regulator, such that a user person may set a temperature for the heating system  10 . The user interface  16  is connected to the electronic controller  13 , which will control the power sent to the heating devices  12  in accordance with the temperature settings entered by the user person with the user interface  16 . As an example, the user interface  16  has a digital display to indicate the settings of the heating system  10 , as well as the temperature measured by the user interface  16 .  
         [0034]     In order to adjust the temperature of the heating devices  12 , the controller  13  may be wired to the sensor  33  of any one of the heating devices  12 , and thus modulate the power supply in accordance with the desired temperature.  
         [0035]     In an embodiment in which a heat transfer fluid is used rather than electric power to transmit heat to the tub surface, the controller  13  is a pump controlling the feed of the heat transfer fluid to the heating panels  20 .  
         [0036]     The heating system  10  of the present invention may be used with any type of tub/spa material, such as acrylic, ABS, steel (e.g., stainless steel), cast iron and the like. The heating devices  12  are preferably secured to parts of the hidden surface of the tub corresponding to parts of the exposed surface of the tub wall above the water line (e.g., the maximum water line), so as to reduce the temperature variation between the fluid and the tub wall. The heating devices  12  are strategically positioned where the bather contacts the tub wall, such as at the backrest of the exposed tub surface.  
         [0037]     It is within the ambit of the present invention to cover any obvious modifications of the embodiments described herein, provided such modifications fall within the scope of the appended claims.