Patent Publication Number: US-2011072613-A1

Title: Spring biased roller for a shower door or the like

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/272,461, filed Sep. 25, 2009 and entitled SPRING BIASED ROLLER FOR A SHOWER DOOR OR THE LIKE, the specification of which is enclosed herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a support structure for a sliding door of a shower or a similar sliding panel arrangement that is spring biased to assist the door to automatically move in one direction. 
     BACKGROUND OF THE INVENTION 
     Shower enclosures typically comprise a stall or base positioned adjacent to one or multiple walls and are enclose by one or multiple glass or polymer panels. To allow access to the shower while allowing keeping water inside the shower a door is generally provided. 
     There exist several possible door configurations. A first common configuration consists of a door mounted on hinges and pivoting about a vertical axis between an open position for accessing the shower and a close position for keeping the water inside the shower enclosure during its use. Some pivoting door configurations make use of mechanisms for maintaining the door in closed position to prevent unwanted opening of the door during the use of the shower, which could result in the shower leaking on the floor or on other structures, which in turn may cause water damages or create an environment favorable to the development of mold. 
     Although this solution may be advantageous, the use of a pivoting door is not possible or not practical in some instances. For example, the space available in some bathrooms may not allow for the use of a pivoting door of convenient size. Also, where the opening of the shower is relatively wide, the use of pivoting door may require the use of robust, relatively unaesthetic hardware to support a pivoting door, especially with glass doors which tend to be very heavy. Other instance where the use of pivoting doors is difficult includes mounting rigid doors to bath enclosures instead of shower curtains. In such instances, the use of sliding shower doors is generally preferred. 
     Sliding shower doors or other sliding panels used in bathrooms, kitchens or other similar environments typically comprise one or multiple vertical panels supported on or by rollers that ride in guide tracks. To operate the panel, the user pushes the panel in one direction to open the door and pushes it back in the opposite direction to close it. While this arrangement may be beneficial when pivoting doors are not suitable, sliding shower doors do not allow for automatic closing and therefore, are more prone to unwanted opening and water leaking. Further, some sliding doors tend to be very heavy, particularly if they are made from glass. This tends to make them difficult to move, especially for users with reduced strength and/or mobility (e.g. elderly people, handicapped people, etc.). 
     To avoid at least some of the above drawbacks, it would be desirable to provide an improved system that facilitates the operation of sliding door panels such that a panel, once moved to one position (opened, closed or to an intermediate position) can be moved back to its original position with less or no efforts. 
     SUMMARY OF THE INVENTION 
     According to a broad aspect of an embodiment of the present invention, there is provided a roller for slidably mounting a panel to a structure. The roller includes a first cylindrical portion having a rolling surface for engaging one of the panel and the structure. The roller also includes a second cylindrical portion fixedly securable to the other one of the panel and the structure. The second cylindrical portion is concentrically mounted to the first cylindrical portion and is rotatable relative thereto in a first rotation direction and in a second, opposed rotation direction. A resilient member is also provided for connecting the first cylindrical portion to the second cylindrical portion for storing a potential energy during rotation of the second cylindrical portion relative to the first cylindrical portion in the first rotation direction, the stored potential energy urging rotation of the second cylindrical portion relative to the first cylindrical portion in the second rotation direction. 
     In an additional feature, the second cylindrical portion is concentrically mounted inside the first cylindrical portion of the first portion. 
     In another feature, the resilient member is a torsion spring including a first end connected to the first cylindrical portion and a second end connected to the second cylindrical portion. 
     In still another feature, the first cylindrical portion includes a first circular side wall having an outer face, an inner face and a circular edge, and an outer cylindrical wall having a first diameter and extending from the inner face of the circular side wall in a first axial direction, the outer cylindrical wall defining the rolling surface. 
     In yet another feature, the second cylindrical portion includes a second circular side wall having an outer face, an inner face and a circular edge. The second cylindrical portion also includes a second cylindrical wall having a second diameter, the second diameter being smaller than the first diameter of the outer wall of the first cylindrical portion. The second cylindrical wall extends from the inner face of the second circular side wall in a second axial direction, opposed to the first axial direction, to concentrically engage the outer cylindrical wall of the first cylindrical portion. 
     In another feature, the resilient member is concentrically mounted between the outer cylindrical wall of the first cylindrical portion and the cylindrical wall of the second cylindrical portion of the roller. 
     In a further feature, the resilient member is a torsion spring comprising a first end connected to the first cylindrical portion and a second end connected to the second cylindrical portion. 
     In still a further feature, the first cylindrical portion comprises a first circular side wall having an outer face, an inner face and a circular edge, an outer cylindrical wall having a first diameter and an inner cylindrical wall having a third diameter smaller than the first diameter of the outer wall. The inner and outer cylindrical walls concentrically extend from the inner face of the circular side wall in a first axial direction, the outer cylindrical wall defining the rolling surface of the roller. 
     In yet a further feature, the second cylindrical portion comprises a second circular side wall having an outer face, an inner face and a circular edge, and a second cylindrical wall having a second diameter. In this feature, the second diameter is smaller than the first diameter of the outer wall but larger than the third diameter of the inner cylindrical wall of the first portion. The second cylindrical wall extends from the inner face of the second circular side wall in a second axial direction, opposed to the first axial direction, to concentrically engage between the inner and outer cylindrical walls of the first cylindrical portion. 
     In another feature, the resilient member is concentrically mounted between the inner cylindrical wall of the first cylindrical portion and the cylindrical wall of the second cylindrical portion. 
     In still another feature, the roller further includes a connector fixedly mounted to the second cylindrical portion for connecting the second cylindrical portion to the panel. 
     In yet another feature, the connector comprises a pin extending outwardly from the outer face of the circular wall. 
     In a further feature, the connector comprises an elongated member extending radially relative to the second cylindrical portion. The elongated member has a first end fixedly connected to the circular wall of the second cylindrical portion and a second end, which comprises a connection means for securing the panel to the connector. 
     In yet a further feature, the connection means comprise a pin extending parallel to a longitudinal axis of the second cylindrical portion and towards the second cylindrical portion to locate the panel secured to the second cylindrical portion below the second cylindrical portion. 
     In another feature, the structure is a shower enclosure and the panel is a shower door. 
     According to another broad aspect of an embodiment of the present invention, there is provided a roller assembly for slidably mounting a panel to a structure. The roller assembly includes a rail secured to the structure, the rail having a first end, a second end and a top surface extending therebetween. The roller assembly also includes at least one roller adapted for moving the panel along the rail. The roller includes a first cylindrical portion including a rolling surface for engaging the top surface of the rail and for rolling therealong when the panel is moved between the first and second ends. The roller also includes a second cylindrical portion fixedly secured to the panel. The second cylindrical portion is concentrically mounted to the first cylindrical portion and is rotatable relative thereto in a first rotation direction and in a second, opposed rotation direction. The roller further includes a resilient member connecting the first cylindrical portion to the second cylindrical portion. The resilient member stores a potential energy during rotation of the second cylindrical portion relative to the first cylindrical portion in the first rotation direction when the panel is moved toward the first end of the rail. The stored potential energy urges rotation of the second cylindrical portion relative to the first cylindrical portion in the second rotation direction thereby urging the panel to move toward the second end of the rail. 
     In one feature, the top surface of the rail and the rolling surface of the first cylindrical portion are complementary to one another. 
     In a further feature, the rolling surface is concave and the top surface is convex. 
     In yet another feature, the first cylindrical portion comprises first and second side walls defining a pair of spaced apart flanges extending radially on each side of the rolling surface and the rail comprises an elongated guide member. The elongated guide member has a rectangular cross-section and is sized to engage the rolling surface between the first and second flanges. 
     In still another feature, the rolling surface comprises a plurality of radially projecting teeth meshing with complementary teeth on the top surface of the rail. 
     In another feature, the structure is a shower enclosure and the panel is a shower door. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A detailed description of examples of implementation of the present invention is provided hereinbelow with reference to the following drawings, in which: 
         FIG. 1  is a top perspective view of a shower having a shower door slidably mounted by means of a roller assembly, in accordance with one embodiment; 
         FIG. 2  is a top perspective view of the roller assembly shown in  FIG. 1 , showing a roller mounted on a rail; 
         FIG. 3  is another top perspective view of the rolling assembly shown in  FIG. 2 ; 
         FIG. 4  is an exploded view of a rolling component for the roller shown in  FIG. 2 ; 
         FIG. 5  is another exploded view of the rolling component shown in  FIG. 4 ; 
         FIG. 6  is a front elevation view of a female portion of the rolling component shown in  FIG. 4 ; 
         FIG. 7  is a cross-section view of the female portion shown in  FIG. 6 , taken along cross-section line VII-VII; 
         FIG. 8  is a front elevation view of a male portion of the rolling component shown in  FIG. 4 ; 
         FIG. 9  is a cross-section view of the male portion shown in  FIG. 8 , taken along cross-section line IX-IX; 
         FIG. 10  is a cross-section view, taken along cross-section line X-X of  FIG. 3 , of the roller shown in  FIG. 2 , with a vertical panel attached to the rolling component via a connector; 
         FIG. 11  is a cross-section view of a roller, in accordance with an alternative embodiment, with a vertical panel attached to the rolling component via a connector; 
         FIG. 12  is a top perspective view of a roller, in accordance with yet another embodiment; 
         FIG. 13  is a cross-section view of a roller, in accordance with yet another embodiment, with a vertical panel attached to the rolling component via a connector; 
         FIG. 14  is a cross-section view of the rolling component shown in  FIG. 2 , taken along cross-section line XIV-XIV, with the spring member in a starting or unwound position; 
         FIG. 15  is another cross-section view of the rolling component shown in  FIG. 14 , with the spring member partly wound; 
         FIG. 16  is a front elevation view, partially cut, of the roller shown in  FIG. 2 , in use with a locking system the latch member of which is engaged; 
         FIG. 17  is a front elevation view, partially cut, of the roller shown in  FIG. 2 , in use with a locking system the latch member of which is released; 
         FIG. 18  is a roller assembly, in accordance with an alternative embodiment; 
         FIG. 19  is a cross-section, partially exploded view, showing assembly of a connector to a male portion, in accordance with one embodiment; 
         FIG. 20  is another cross-section, partially exploded view showing assembly of a connector to a male portion, in accordance with an alternative embodiment. 
     
    
    
     In the drawings, embodiments of the invention are illustrated by way of example. It is to be expressly understood that the description and drawings are only for purposes of illustration and as an aid to understanding, and are not intended to be a definition of the limits of the invention. 
     DETAILED DESCRIPTION 
     The description which follows, and the embodiments described therein are provided by way of illustration of an example, or examples of particular embodiments of principles and aspects of the present invention. These examples are provided for the purpose of explanation and not of limitation, of those principles of the invention. In the description that follows, like parts are marked throughout the specification and the drawings with the same respective reference numerals. 
     With reference to  FIG. 1 , there is shown a shower  100  comprising a base  102  mounted in a shower enclosure  104  defined by a pair of spaced-apart side walls  106 ,  108  and a back wall  110  extending perpendicular to the side walls  106 ,  108  and connecting the same. An opening  112  is defined between the side walls  106 ,  108  to access the shower enclosure  104 . In the embodiment shown in  FIG. 1 , the opening  112  is closed by a sliding door assembly  114  comprising a pair of generally vertical panels  118   a ,  118   b  and a roller assembly for slidably mounting the mounted to the vertical panels  118   a ,  118   b  to the side walls  106 ,  108 . The roller assembly comprises a generally horizontal track or rail  116  extending between the side walls  106 ,  108  of the shower enclosure  104 , spaced above the base  102  to allow a user to conveniently enter the shower enclosure  104 . The vertical panels  118   a ,  118   b  are suspended to the rail  116  by way of rollers  120  and are movable sideward to open and close the opening  112  of the shower  100 . Each of the vertical panels  118   a ,  118   b  comprises a lower end  122 , an upper end  124  and a pair of opposed side ends  126 . In the embodiment shown in  FIG. 1 , each of the vertical panels  118   a ,  118   b  is suspended to the rail  116  by two rollers  120  attached to the upper end  124 . As it will become apparent below, the rollers  120  of each of the vertical panels  118   a ,  118   b  are spring biased to facilitate lateral movement of the two vertical panels  118   a ,  118   b  to thereby assist the user in closing and/or to automatically close the shower opening  112  and prevent water leaks, or to assist the user in opening and/or to automatically open the shower opening  112 . 
     Now turning to  FIGS. 2 and 3 , the roller  120  will be described in connection with one embodiment. In this embodiment, the roller  120  comprises a rolling component  200  adapted for engaging the rail  116  and a connector  202  secured to the rolling component  200  for suspending a corresponding one of the vertical panels  118   a ,  118   b  to the rolling component  200 , as it will become apparent below. The rolling component  200  has a cylindrical wall  204  which defines a rolling surface  206  adapted for contacting and resting upon a top surface  208  of the rail  116  such that, when the sliding door assembly  114  is assembled, the rail  116  substantially supports the rolling component  200  and the corresponding vertical panel  118  attached thereto. In the embodiment illustrated in  FIG. 1 , the rail  116  is located near the top of the shower opening  110  and the corresponding vertical panel  118  is suspended from the rail  116  by means of the roller  120 , the lower end  122  of the vertical panels  118   a ,  118   b  being adjacent to the base  102  of the shower  100 . 
     Now referring to  FIGS. 4 and 5 , the rolling component  200  comprises a first, female portion  400  and a second, male portion  402  rotatably engaging the female portion  400 . As it will become apparent below, the male portion  402  is fixedly connected to the connector  202  and to the vertical panel  118   a ,  118   b , and the female portion  400  is free to rotate about the male portion  402 . Therefore, when the vertical panel  118   a  or  118   b  is moved sidewardly, the female portion  400  is allowed to rotate relative to the male portion  402  to displace the roller  120  along the rail  116 . 
     The rolling component  200  further comprises a resilient or spring member  404  which connects the male portion  402  to the female portion  400 . In the embodiment illustrated in  FIGS. 4 and 5 , the spring member  404  comprises a first end  406  connected to the female portion  400  and a second end  408  connected to the male portion  402 . When the vertical panel  118  is forced laterally in the first lateral direction  250 , for instance by a user desirous to enter or exit the shower  100 , the female portion  400  of the rolling component  200  engages the rail  116  and rotates relative to the male portion  402 , thereby causing the first end  406  of the spring member  404  to move relative to the second end  408  of the spring member  404  (best shown in  FIGS. 14 and 15 ). As it will be appreciated by a person skilled in the art, this causes the spring member  404  to be wound or unwound and to spring bias the rolling component  200 . On the other hand, when the rolling component  200  is biased and the vertical panel  118   a  or  118   b  is released by the user (i.e. not lateral force is exerted on the vertical panel  118   a  or  118   b , the wound spring member  404  will tend to unwind, therefore causing the rotation of the female portion  400  relative to the male portion  402  in an opposite rotation direction. Because the female portion  400  engages the rail  116 , unwinding of the spring member  404  will cause the roller  120  and the panel  118   a  or  118   b  attached thereto to move back towards its original position (i.e. in a travel direction opposite to direction  250 ). 
     In the embodiment illustrated in  FIGS. 4 to 7 , the female portion  400  has a generally cylindrical shape and comprises a first and second side ends  410 ,  412 . At the first side end  410  thereof, the female portion  400  comprises a circular wall  414  having an outer face  416 , an inner face  500  and a circular edge  418  having a diameter D 1  (shown in  FIG. 6 ). Extending from the inner face  500  of the circular wall  414 , toward the second side end  412  of the female portion  400  (i.e. in a first axial direction), are two cylindrical walls, namely an inner cylindrical wall  502  and an outer cylindrical wall  504 . The inner and outer cylindrical walls  502 ,  504  each have a first side end  700 ,  702  attached to the circular wall  414  and a second, opposed side end  704 ,  706  and extend longitudinally along a rotation axis R-R of the rolling component  200 . The inner and outer cylindrical walls  502 ,  504  are positioned concentrically relative to one another so as to define a cylindrical space  510  therebetween. As it will become apparent below, the space  510  is sized to accommodate the male portion  402  of the rolling component  200  and the spring member  404 . Accordingly, the inner cylindrical wall  502  has a diameter D 2 , smaller that a diameter D 3  of the outer cylindrical wall  504  (best shown in  FIG. 6 ). 
     At the second side end  412  thereof, the female portion  400  is provided with an annular wall  420  connected to the second side end  706  of the outer cylindrical wall  504 . The annular wall  420  has an inner face  422  generally facing towards the second end  706  of the outer cylindrical wall  504  and an outer face  512  generally facing away from second end  706  of the outer cylindrical wall  504 . The annular wall  420  further has an inner circular edge  514  having a diameter D 4  corresponding to the diameter D 3  of the outer cylindrical wall  504  and an outer circular edge  516  having a diameter D 5 , which generally correspond to the diameter D 1  of the circular wall  414 . As best shown in  FIG. 7 , the diameter D 3  of the outer cylindrical wall  504  is smaller than the diameters D 1  and D 5  of the circular and annular walls  414 ,  420  and therefore, the circular and annular walls  414 ,  420  protrude radially from the outer cylindrical wall  504 . Accordingly, the circular and annular walls  414 ,  420  define spaced apart guiding surfaces for maintaining the rolling component  200  on the rail  116  as the vertical panel  118  is moved laterally along the rail  116 , while the exterior of the outer cylindrical wall  504  defines the rolling surface  206  of the rolling component  200 , as it will be best described below. 
     Further, because the annular wall  420  has a thickness T 1 , the second end  704  of the inner cylindrical wall  502  is slightly recessed relative to the outer face  512  of the annular wall  420  (i.e. the second end  704  of the inner cylindrical wall  502  is in vertical alignment with the inner face  422  of the annular wall  420 ). 
     As shown in  FIG. 5 , the inner cylindrical wall  502  is provided with a longitudinal slot  550 . In the embodiment illustrated, the longitudinal slot  550  extends generally from the second side end  508  towards the first side end  506  of the inner cylindrical wall  502 , substantially parallel to the rotation axis R-R, and is configured to engage the first end  406  of the spring member  404 , as it will become apparent below. 
     Referring to  FIGS. 4 ,  5 ,  8  and  9 , the male portion  402  of the rolling component  200  will now be described. The male portion  402  is configured to fit within the space  510  defined between the inner and outer cylindrical walls  502 ,  504  of the female portion  400  and to rotate relative thereto. More specifically, the male portion  402  comprises a generally cylindrical wall  430  having a first end  800 , engaging the space  510 , and a second, opposed end  802 . The cylindrical wall  430  of the male portion defines a chamber  436  sized to receive the spring member  404  therein. The cylindrical wall  430  extends from a generally circular wall  438  in a second axial direction, opposed to the first axial direction of the female portion  400 , and is provided with a slot  450  extending generally between the first and second ends  800 ,  802  thereof, substantially parallel to the rotation axis R-R, for engaging the second end  408  of the spring member  404 . 
     More specifically, the generally circular wall  438  of the male portion  402  comprises an inner face  440  fixedly attached to the second end  802  of the cylindrical wall  430 , an outer face  518  and a thickness T 2  (shown in  FIG. 9 ), which corresponds generally to the thickness T 1  of the annular wall  420  of the female portion  400 . In the embodiment illustrated in  FIGS. 4 and 5 , a fastening hole  460  is defined in the circular wall  438  and is generally centered thereon to accommodate a fastener for fastening the connector  202  to the male portion  402 , as will be further described below. The cylindrical wall  430  further comprises a circular edge  442  having a diameter D 6  sized slightly smaller than the diameter D 4  of the inner circular edge  514  of the annular wall  512  of the female portion  400 . Accordingly, when the male portion  402  is properly engaged in the female portion  400 , the outer face  518  of the circular wall  438  of the male portion  402  is aligned with the outer face  512  of the annular wall  420  of the female portion  400  and yet, rotation of the male portion  402  relative to the female portion  400  is allowed. 
     Referring back to  FIGS. 4 and 5 , the spring member  404  interconnects the female and male portions  400 ,  402  and is adapted to urge rotation of the female portion  400  about the male portion  402 . In this embodiment, the spring member  404  is made of a strip of resilient material (such as metal or plastic) that is wound into a spiral form. More specifically, the spring member  404  is a torsion spring comprising the first and second ends  406 ,  408  and a coiled portion  444  extending therebetween. The first end  406  comprises a first or inner tab  446  extending generally radially and inwardly, towards the rotation axis R-R, the inner tab  446  being receivable in the slot  550  to engage the inner cylindrical wall  502  of the female portion  400 . Similarly, the second end  408  comprise a second or outer tab  448 , extending outwardly and generally radially, the outer tab  448  being receivable in the slot  450  to engage the cylindrical wall  430  of the male portion  402 . As it will be appreciated by a person skilled in the art, the rotation of the female portion  400  relative to the male portion  402  in one direction (e.g. when the door is opened) will cause the spring member  404  to wind and to store energy while the accumulated energy will cause the spring member  404  to unwind and to force rotation of the female portion  400  in the opposite direction and thereby to urge lateral movement of the vertical panel  118  attached to the rolling component  200  via the connector  202  (e.g. to close the door). It will be appreciated that the above configuration of the spring member  404  is provided merely as an example and that the spring member  404  may be attached to the female and male portions  400 ,  402  of the rolling component  200  using any other suitable means known to the skilled addressee. 
     Having described the rolling component  200 , the connector  202  attached thereto will now be described, with references to  FIGS. 2 and 3 . According to this embodiment, the connector  202  is generally elongated and comprises first and second opposed, bulbous end portions  210 ,  212 . A generally biconcave central portion  300 , which is substantially narrower than the first and second end portions  210 ,  212 , extends between the first and second end portions  210 ,  212 . The first end portion  210  is fixedly attached to the male portion  402  of the rolling component  200  and the connector  202  extends generally radially therefrom. A pin  216  extends from the second end portion  212 , towards the rolling component  200  and parallel to the rotation axis R-R thereof, for engaging the vertical panel  118   a ,  118   b , as best shown in  FIG. 10 . It will be appreciated that this configuration allows the weight of the vertical panel  118   a ,  118   b  to be balanced underneath the rail  116 . Therefore, the weight of the vertical panel  118   a ,  118   b  will advantageously urge the rolling component  200  in an upright position, which is desirable to obtain proper rolling of the rolling component  200 . Otherwise, the weight of the panel may cause the rolling component  200  to tip over. 
     In the illustrated embodiment, an opening  302  is defined in the central portion  300  of the connector  202 . It will be appreciated that the substantially narrow shape of the central portion  300  and the opening  302  advantageously contribute to reducing the weight of the connector  202  to thereby reducing the amount of force needed to move the vertical panel  118  laterally while providing sufficient structural strength to allow the connector  202  to support the vertical panel  118 . The substantially narrow shape of the central portion  300  and the opening  302  further reduce the amount of material needed to manufacture the connector  202 , which advantageously allows substantial savings on manufacturing costs, especially in a case in which a large number of connectors are to be manufactured, and provides an aesthetically pleasant look to the roller  120 . 
     To assemble the roller  120 , the connector  202  is secured to the male portion  402  of the rolling component  200 . In the embodiment illustrated in  FIG. 19 , a threaded fastener  1900  is used for this purpose. The threaded fastener  1900  comprises a head  1902  and an opposed tip  1904 . The tip  1904  of the threaded fastener  1900  is inserted through the fastening hole  460  of the male portion  402 , from the chamber  436  towards the outer face  512 . The head  1902  of the threaded fastener  1900  may be larger than the diameter of the fastening hole  460  such that the head  1900  may abut the inner face  440  of the circular wall  438  of the male portion  402 , or a suitable washer  1906  may be used to prevent the head  1902  of the threaded fastener  1900  from passing through the fastening hole  460 . The tip  1904  of the threaded fastener  1900  is then engaged in a corresponding threaded hole  1908  provided in the first end portion  210  of the connector  202 . The threaded hole  1908  extends generally parallel to the rotation axis R-R of the rolling component  200  such that when the connector  202  is fastened to the male portion  402  of the rolling component  200 , the connector  202  extends generally radially relative to the rolling component  200 . Referring to  FIG. 20 , a set screw  2000  may further be used to prevent unwanted rotation of a grooved pin  2002  during operation of the roller  120 . The set screw  2000  is fastened in a threaded bore  2004 , which extends perpendicularly to a pin receiving hole  2006  defined in the connector  202 , until the set screw  2000  abuts the grooved pin  2002  and exerts sufficient pressure thereon to prevent rotation of the connector  202  relative to the grooved pin  2002 . Alternatively, the pin receiving hole  2006  may be internally threaded, similarly to the threaded hole  1908  described above, and the set screw  2000  may engage a longitudinal groove of a threaded fastener, generally similar to the threaded fastener  1900  described above, to prevent rotation of the connector  202  relative to the threaded fastener. 
     A person skilled in the art will appreciate that many configurations for attaching the connector  202  to the male portion  402  are possible. For instance, the connector  202  may instead comprise a connecting pin, similar to the pin  216 , which extends from the first end portion  210  of the connector  202 , generally parallel to the pin  216  (not shown). The connecting pin may be threaded at its free end such that it may be inserted through the fastening hole  460  of the male portion  402  to extend into the chamber  436  for threadingly engaging a nut. In yet another embodiment, the male portion  402  of the rolling component  200  and the connector  202  may be manufactured as a single, monolithic member. 
     The rolling component  200  is assembled by first assembling the spring member  404  with one of the female and male portions  400 ,  402  of the rolling component  200 . In one embodiment, the spring member  404  is placed in the chamber  436  of the male portion  402  of the rolling component  200  and the outer tab  448  of the spring member  404  is inserted in the slot  450  of the cylindrical wall  430  of the male portion  402 . In an alternative embodiment, the spring member  404  is placed in the space  510  of the female portion  400  of the rolling component  200  and the inner tab  446  of the spring member  404  is inserted in the slot  550  of the inner cylindrical wall  502  of the female portion  400 . 
     The male portion  402  and the female portion  400  are then assembled together. The male portion  402  (to which the connector  202  was previously attached) is inserted in the space  510  of the female portion  400 . Specifically, the cylindrical wall  430  of the male portion  402  is lined up concentrically relative to the outer cylindrical wall  504  of the female portion  400 , with the chamber  436  of the male member  402  facing the space  510  of the female member  400 . The female and male members  400 ,  402  are then moved towards each other. If the outer tab  448  of the spring member  404  was previously inserted in the slot  450  of the cylindrical wall  430  of the male portion  402 , the inner tab  446  of the spring member  404  is aligned with the slot  550  of the inner cylindrical wall  502  of the female portion  400  such that movement of the male and female members  400 ,  402  towards each other will insert the inner tab  446  into the slot  550  of the inner cylindrical wall  502  of the female portion  400 . If the inner tab  446  of the spring member  404  was previously inserted in the slot  550  of the inner cylindrical wall  502  of the female portion  400 , the outer tab  448  of the spring member  404  is aligned with the slot  450  of the cylindrical wall  430  of the male portion  402  such that movement of the male and female members  400 ,  402  towards each other will insert the outer tab  448  into the slot  450  of the cylindrical wall  430  of the male portion  402 . Once assembled, the roller  120  may be placed on the rail  116 , as explained below. 
     The rolling component  200  and the connector  202  may be made of any suitable material known by the skilled addressee such as metal or a synthetic material. In one embodiment, the rolling component  200  and the connector  202  are made of a plastic material such as polyvinylchloride (PVC), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyethylene (PE) or polypropylene (PP). This is particularly advantageous if the roller  120  is used in an environment in which it may be exposed to water, such as on a shower door, because plastics generally have a substantially high tolerance to corrosion. 
     Now turning to  FIG. 10 , the roller  120  is shown, assembled and mounted on the rail  116 . The rail  116  itself is mounted over the panels  118   a  and  118   b  which extend vertically, substantially parallel to one another. 
     The rail  116  has a cross-sectional shape that is complementary to the shape of the rolling surface  206  of the rolling component  200 . Specifically, the rail  116  comprises an elongated guide member  1004  which defines the top surface  208  of the rail  116  and a bottom end  1008 . In the illustrated embodiment, the elongated guide member  1004  has a generally rectangular cross section and is slightly narrower than the outer cylindrical wall  504  of the female member  400 . When the rolling component  200  is properly mounted on the rail  116 , the top surface  208  of the rail  116  contacts the rolling surface  206  of the rolling component  200 , and the elongated guide member  1004  is therefore located between the circular and annular walls  414 ,  420  of the female portion  400 . This allows the rolling surface  206  of the rolling component  200  to roll on the top surface  208  of the rail  116  while the circular and annular walls  414 ,  420  of the female portion  400 , which define flanges acting as guiding surfaces, substantially prevent the rolling component  200  to move transversely relative to the rail  116  and thereby advantageously prevent the roller  120  from accidentally being disengaged from the rail  116 . 
     The rail  116  further comprises a pair of opposed sidewalls  1020  which extend generally downwardly from the elongated guide member  1004 . The sidewalls  1020  are spaced apart to define a panel guiding channel  1022  therebetween for guiding the first panel  118   a  along the rail  116 . In the illustrated embodiment, the panel guiding channel  1022  is adapted for guiding the first panel  118   a , which is movable, along the second panel  118   b , which is fixed. The width of the panel guiding channel  1022  is selected such as to accommodate the combined thickness of the first panel  118   a  and the second panel  118   b  as well as a sufficient clearance to allow the first panel  118   a  to slide past the second panel  118   b.    
     To further prevent transverse movement of the rolling component  200  relative to the rail  116 , an upper guiding track  1010  may further be provided. The upper guiding track  1010  is spaced upwardly from the rail  116  and is positioned slightly above the rolling component  200 . The upper guiding track  1010  comprises a substantially flat top wall  1012  and a pair of opposed sidewalls  1014 ,  1016  extending generally downwardly on each side of the top wall  1012 . The opposed sidewalls  1014 ,  1016  are spaced apart to define a roller guiding channel  1018  therebetween for receiving the rolling component  200  while allowing its rotation. To that end, the roller guiding channel  1018  is slightly wider than the rolling component  200  to allow the rolling component  200  to roll freely within the roller guiding channel  1018 . In this configuration, the rolling component  200  is located within the roller guiding channel  1018  and the opposed sidewalls  1016  substantially prevent transverse movement of the rolling component  200  relative to the rail  116 , as well as upward movement of the rolling component  200 . It will be appreciated that it may be particularly advantageous to prevent transverse movement of the rolling component  200  in order to prevent it from tipping over when the first panel  118   a  attached thereto is substantially heavy. 
     Still referring to  FIG. 10 , a hole  1024  is provided in the first panel  118   a  to receive the pin  216  of the connector  202 . In one embodiment, the hole  1024  has substantially the same diameter as the pin  216  to allow the pin  216  to be simply inserted in the hole  1024 . When the pin  216  is engaged in the hole  1024  of the first panel  118   a , the weight of the first panel  118   a  pulls the connector  202  downwardly and prevents it from rotating along with the female portion  400  when the rolling component  200  is rolling. Since the male portion  402  of the rolling component  200  is secured to the connector  202 , the male portion  402  is also prevented from rotating. Further, the rail  116 , which is securely positioned above the first panel  118   a , prevents the first panel  118   a  from moving upwardly, and thereby further prevents the male portion  402  from rotating. Therefore, since the female portion  400  rotates when the rolling component  200  rolls, but the male portion  402  is prevented from rotating, the female portion  400  rotates relative to the male portion  402  when the rolling component  200  is rolling to wind or unwind the spring member  404 . 
     Alternatively, prior to insertion, the pin  216  may be covered with an adhesive know in the art to secure the pin  216  in the hole  1024  and thereby prevent further movement of the connector  202  relative to the first panel  118   a . The hole  1024  may also have a diameter which is slightly inferior to the diameter of the pin  216  to allow the pin  216  to be secured in the hole  1024  by a press-fit engagement. It will be appreciated that the pin  216  may be secured in the hole  1024  of the first panel  118   a  using any fasteners or fastening methods known to a person skilled in the art. 
     Now, with references to  FIGS. 1 ,  14  and  15 , the operation of the roller  120  will be described, in accordance with one embodiment. In this embodiment, the roller  120  supports the vertical panel  118  which acts as a door of the shower  100 . In a starting position, shown in  FIG. 14 , the spring member  404  is unwound and at equilibrium. This position may correspond to the shower door  118  being in a closed position, for instance. In this embodiment, the shower door  118 , when closed, abuts a left wall  106  of the shower enclosure  104 . To open the shower door  118 , a user facing the shower  100  exerts a lateral, rightward force on the shower door  118  to displace it rightwardly. Due to the friction of the rolling surface  206  of the rolling component  200  on the rail  116 , the female portion  400  of the rolling component  200  rotates in the rotation direction indicated by arrow D. As the user keeps exerting a rightward force on the shower door  118 , the rolling component  200  continues rolling rightwardly and the female portion  400  of the rolling component  200  keeps rotating relative to the male portion  402 . As shown on  FIG. 15 , this causes the spring member  404  to deform from its starting or unwound position and to wind around the inner cylindrical wall  502  of the female portion  400  of the rolling component  200 . As the user is exerting a force and moving the shower door  118  rightwardly, the user also provides kinetic energy to the roller  120  by causing the female portion  400  of the rolling component  200  to rotate relative to the male portion  402 . This kinetic energy is transformed by the spring member  404  into potential energy, which is stored within the spring member  404 . When the user lets go of the shower door  118 , the spring member  404  urges the rolling component  200  back towards the starting, equilibrium position. It will be appreciated that the spring member  404  may be configured for providing the necessary force to move the shower door  118  back at the starting position without the need for any intervention from the user. Alternatively, the spring member  404  can be configured to provide a lesser degree of force that may not completely close the shower door  118  by itself, but can reduce the effort that would otherwise be required on the part of a user. 
     In an alternative embodiment, the spring member  404  may not be at equilibrium when in the start position, but already be partially wound. This would cause the shower door  118  to be biased against the left wall  106  of the shower enclosure  104 . This configuration would advantageously enhance watertightness of the shower stall  102  when the shower door  118  is closed, especially if the shower door  118  is provided with a shower door seal or shower door gasket. 
     In yet another embodiment, the roller  120  may instead be configured such that the shower door  118  is biased towards an open position instead of a closed position. For instance, the roller  120  described herein may be used with a locking mechanism  1600 , as shown in  FIGS. 16 and 17 . When in a locked position, shown in  FIG. 16 , the spring member  404  urges the shower door  118  rightwardly, but the shower door  118  is retained by a latch member  1602  which engages a retaining member, in this case a wall portion  1604  of a cavity  1606  defined in the left wall  106  of the shower enclosure  104 . The latch member  1602  is operable using a handle  1608  which, when activated—by turning in the illustrated embodiment—releases the shower door  118 . The spring member  404  may be configured for laterally moving the shower door without requiring any intervention from the user. In one embodiment, the latch member  1602  may only be released after a specific event, such as the payment of a fee or the like. This system may therefore advantageously be used to provide paying showers in public areas, for instance. 
     Although a single configuration, in which a single vertical panel  118  is movable and supported by two rollers  120 , is shown in  FIGS. 1 ,  14  and  15 , the skilled addressee will appreciate that various other configurations may be considered. For instance, the vertical panel  118  may be supported by more than two rollers  120 . In one embodiment, a shower door may comprise two vertical panels  118 , each movable. In this case, the rolling components  200  supporting a first panel may act as abutments for the rolling components  200  supporting a second panel, in order to avoid damaging the panels by opening them too forcefully and accidentally ramming them in the opposed sidewall. 
     The rail  116  may also be shaped according to one of various configurations known to the skilled addressee. In the embodiment illustrated in  FIG. 1 , the side walls  106 ,  108  are substantially parallel and the rail  116  extends generally linearly therebetween. Alternatively, the shower  100  may comprise only a single side wall  106  and the back wall  110 . This embodiment advantageously allows the shower  100  to be located in a corner of a room, such as a bathroom, adjacent to two existing walls. In this case, the rail  116  is curved in a substantially horizontal plane and extends between the side wall  106  and the back wall  110 . 
     To prevent undesired unwinding of the spring member  404  during movement of the rolling component  200  along the rail  116 , it may be desirable to enhance friction between the rolling component  200  and the rail  116 . For instance, the rolling component  200 , the rail  116 , or both can be made of friction-enhancing materials that reduce the likelihood of the rolling component  200  starting to slip as the spring member  404  is being wound. An example of such material is an elastomer (e.g. rubber or a rubber-like coating), that can be applied to the rolling surface  206  of the rolling component  200  and/or to the top surface  208  of the rail  116 . In addition to providing enhanced friction, the elastomeric material will also cushion movement of the vertical panel  116  to some degree. Alternatively, a surface finish may be applied to the rolling component  200 , the rail  116  or both to enhance friction of the rolling component  200  on the rail  116 . Such surface finish may include one or more of etching, embossing or otherwise treating the surface of the rolling component  200 , the rail  116  or both, such that the treated surface becomes rougher. It will be appreciated that a surface finish may be used in conjunction with a friction-enhancing material to yet further reduce the likelihood of slippage of the rolling component  200 . In yet another embodiment, shown in  FIG. 18 , the rolling component  200  may be gear-shaped and comprises, along its rolling surface  206 , a plurality of teeth  1800  which are adapted for meshing with corresponding teeth  1802  provided on the rail  116 , thereby substantially reducing or essentially eliminating slippage of the rolling component  200  on the rail  116 . 
     In an alternative embodiment, the rail  116  may be configured to completely unwind the spring member  404  when the shower door  118  is in the closed position. This can be achieved by providing along the rail  116  localized areas with a low-friction material that registers with the rolling components  200  when the shower door  118  is in the closed position. At this point, the rolling components  200  are allowed to slip and thus completely unwind the spring member  404 . 
     It will be appreciated that the rail  116  and the rolling component  200  may be constructed according to various other designs known to a skilled addressee which would allow the rolling component  200  to roll while being guided along the rail  116 . For instance, in an alternative embodiment shown in  FIG. 11 , the rolling component  200  comprises a generally concave wall  1100  which defines a curved rolling surface  1102 . The rail  116  has a generally dome-shaped cross-section and comprises a top bulging portion  1104  having a curvature substantially similar to the curvature of the curved rolling surface  1102  of the rolling component  200  to allow the rolling component  200  to be guided along the rail  116 . A generally rectangular recess  1106  further extends upwardly from a lower end of the rail  116  into the rail  116 . The rectangular recess  1106  is sized and shaped to form a panel guiding channel  1108  for guiding the first panel  118   a  along the second panel  118   b , as explained above. In the illustrated embodiment, a hemicylindrical recess  1110  further extends from the rectangular recess  1106  upwardly towards the top bulging portion  1104 . The hemicylindrical recess  1110  advantageously reduces the weight of the rail  116  while reducing the amount of material needed to manufacture the rail  116 , which advantageously allows substantial savings on manufacturing costs, especially in a case in which a large number of rails are to be manufactured. 
     An upper guide track  1112  is further provided to substantially prevent the rolling component  200  from moving transversely relative to the rail  116 . The upper guide track  1112  is spaced upwardly from the rail  116  and is adapted for receiving an upper portion  1150  of the rolling component  200 . In the illustrated embodiment, the upper guide track  1112  is similar to the rail  116  and comprises a generally rectangular recess  1114  which extends upwardly from a lower end  1116  of the upper guide track  1112  into the upper guide track  1112 . The rectangular recess  1114  is slightly wider than the rolling component  200  to allow the rolling component  200  to roll along the rail  116  while preventing the rolling component  200  from moving transversely relative to the rail  116 . A person skilled in the art will appreciate that it may be advantageous for the upper guide track  1112  to be similar to the rail  116 , for instance to reduce manufacturing cost if the sliding door assembly  114  is to be manufactured in large quantities. 
     Now turning to  FIG. 12 , there is shown yet another embodiment of a roller  1200 . The roller  1200  comprises a rolling component  1202  having a concave wall  1204  defining a curved rolling surface  1206 , as described above in connection with concave wall  1100 . The rolling component  1202  comprises a female portion  1208  and a male portion  1210  rotatably connected to the female portion  1208 . The roller  1200  further comprises a connector  1212  secured to the male portion  1210  of the rolling component  1202 . In this embodiment, the connector  1212  has a generally obround shape and has a first end  1214  secured to the male portion  1210  of the rolling component  1202  and a second, opposed end  1216 . A pin  1218  extends away from the second end  1216  of the connector  1212 , towards the rolling component  1202  and generally parallel to a rotation axis R-R thereof. As illustrated, the pin  1218  or a portion of the pin  1218  located at its free end  1220  may be threaded to receive a corresponding nut (not shown). When properly installed, the pin  1218  is inserted through a receiving hole of a corresponding panel. The pin  1218  has a length sufficient to allow its free end  1220  to protrude from the corresponding panel. The nut threadingly engages the free end  1220  of the pin  1218  and is tightened to sandwich the corresponding panel between the nut and the connector  1212  to thereby prevent further movement of the corresponding panel relative to the connector  1212 . 
     It will be appreciated that the rolling component  200  may have other configurations. For instance, instead of a concave wall  1204  defining a rolling surface  1206  curving inwardly, the rolling component  200  may instead comprise a convex wall defining a rolling surface curving outwardly. In this embodiment, the top surface of the rail  116  may be shaped to fit this outwardly curved rolling surface. For instance, the rail  116  may comprise a longitudinal guide member in which is defined a concave recess, the curvature of which corresponds to the curvature of the outwardly curved rolling surface of the rolling component  200 . Alternatively, the rolling component  200  may instead have a lenticular shape, in which case the rail  116  may be provided with a corresponding generally V-shaped recess. It will be appreciated that all of the above-described shapes may substantially prevent the rolling component  200  from moving transversely relative to the rail  116  when the rail  116  has a cross-section which is substantially complementary to the shape of the rolling component  200 . Various other shapes and configurations known to the skilled addressee may be considered. In yet another embodiment, the rolling component  200  does not comprise guiding surfaces, such as the annular and circular walls  414 ,  512  of the female portion  400 . Instead, the rolling component  200  is fully cylindrical and is adapted to engage a substantially planar top surface of the rail  116 . 
       FIG. 13  shows yet another embodiment of a roller  1300 . In the illustrated embodiment, the roller  1300  is located near a bottom portion  1302  of a vertical panel  1304   a . The roller  1300  comprises a rolling component  1306  having a female portion  1308  and a male portion  1310 , similarly to the rolling component  200  described above, and a connector  1312  for attaching the vertical panel  1304   a  to the rolling component  1306 . In this embodiment, the connector  1312  comprises a pin  1314  extending from the male portion  1310  of the rolling component  1306 , away from the female portion  1308  and generally parallel to the rotation axis R-R of the rolling component  1306 . A rail  1316  is further provided for the rolling component  1306  to engage. The rail  1316  is secured on a bottom surface such a bathroom floor or a shower base (e.g. shower base  102 ) and comprises a base  1318  and an elongated guide member  1320  extending upwardly from the base  1318 . The rail  1316  is positioned adjacent the vertical panel  1304   a  such that the pin  1314  may engage a hole  1322  of the vertical panel  1304   a . In one embodiment, the vertical panel  1304   a  is supported by the pin  1314  of the rolling component  1306 . Alternatively, the vertical panel  1304   a  may be supported in part by the rolling component  1306 , and in part by a guide track  1324  extending below the vertical panel  1304   a . In this embodiment, the guide track  1324  is distinct from the rail  1316  and comprises a base wall  1326  and a pair of opposed sidewalls  1328 ,  1330 , spaced apart to define a panel guiding channel  1332  therebetween. The vertical panels  1304   a  and  1304   b  engage the panel guiding channel  1332  and are partly supported on the base member  1326 . Although in this example, the rolling component  1306  supports the bottom portion  1302  of the vertical panel  1304   a , the skilled addressee will understand that the present configuration may be configured to engage a top portion of the vertical panel  1304   a.    
     In yet another embodiment, the male portion  402  of the rolling component  200  may be fixed to a wall structure such that the rolling component  200  is not allowed to move laterally. For instance, a first plurality of rolling components  200  may be aligned substantially horizontally near a ground surface and their male portion may be secured to the wall structure in this fashion. A second plurality of rolling components  200  may be aligned substantially horizontally and their male portion secured to the wall structure, above the first plurality of rolling components  200 . A panel, such as a glass panel, would then be slid between the first and second pluralities of rolling components, the first plurality of rolling components engaging the bottom edge of the panel while the second plurality of rolling components engages the top edge of the panel. Sliding the panel between the first and second pluralities of rolling components in a first direction would wind the spring member of the rolling components, which would be urged back towards their original position when the panel is released. 
     Although the foregoing description related mainly to shower doors, it will be appreciated that the roller assembly described herein may be used in various other applications which comprise a sliding panel or structure that is designed to be moved between an opened and a closed position. Examples of such alternative arrangements include sliding doors for bathroom stalls, kitchen or bathroom cabinets and even drawer structures for bookshelves or audio-visual entertainment centers, among others. Shower doors using the rollers described herein may also be installed over the rim of an existing bathtub to create an enclosed space. Further, the roller  200  may be suitably used with generally vertical, horizontal or slanted panels. 
     Although the above description relates to a specific preferred embodiment as presently contemplated by the inventor, it will be understood that the invention in its broad aspect includes mechanical and functional equivalents of the elements described herein.