Abstract:
A hinge device for a door is provided. The hinge device has two hinge members which engage with each other and a hinge cap. A bearing with one or more tapered ends engages with the hinge members to allow easy opening and closing of a door attached to the hinge device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/947,655, filed Mar. 4, 2014, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention generally relates to gear hinges and more specifically to gear hinge devices employing a bearing having an end edge which is not entirely perpendicular to the longitudinal axis of the hinge. 
     Because doors attached to a door frame with traditional pin-type hinges have their weight concentrated at a few relatively small areas where the hinges are located, continuous gear hinges are often preferable. Gear hinges usually extend the entire length of a hinge jamb or door, and thus distribute the weight of the door over a much larger area. For this reason, gear hinges are often installed on doors which see heavy use, such as those found in bathroom stalls. 
     A gear hinge typically has two opposing hinge members, each having a longitudinal leaf and a gear segment for meshing with an opposing gear segment, a hinge cap or clamp for holding the gear segments together so that one leaf can rotate relative to the other leaf while the gear segments remain meshed, and one or more bearing blocks for preventing one hinge member from shifting longitudinally relative to another hinge member. A gear hinge for a typical door will have several bearing blocks fitted into cutouts formed in the leaves and gear segments, and these bearing blocks, which are usually molded from plastic, carry essentially the entire weight of the door. As the hinge opens and closes, the ends of the cutouts in the gear segments slide over the end edges of the plastic bearing blocks, which can cause unwanted friction and wear over time. Plus, such doors with common gear hinges do not open or close automatically, without additional hardware. 
     Bathroom stalls subject to the Americans with Disabilities Act (ADA) must have doors that are self-closing. To achieve such a self-closing door, some doors use springs. However, these springs are subject to failure. Moreover, for non-ADA bathroom stall doors, there is a demand for a door that returns to a specific, non-closed position. This position is typically 15°-20° with respect to the closed position, leaving enough of an opening for a person to easily determine whether the stall is occupied or not. 
     One embodiment of the present invention is a gear hinge assembly including a pair of mating hinge members and one or more bearing blocks. Each bearing block has one or more non-perpendicular—with respect to the longitudinal axis—end edge surfaces. This provides a low friction device which makes it easier to open and close the door, as well as reducing wear of the bearing blocks and gear hinge cutout edges. The end edges of the bearing blocks are preferably helically shaped. In addition, the gear segment portions may have ends which are shaped and sized to mate with the end edges of the bearings. Such a configuration results in a self-closing door. 
     A device such as a spring plunger may be used to hold the door open a desired amount so a person can easily see if a bathroom stall is occupied. The force of the spring in the spring plunger can easily be overcome to close the stall door. 
     Other advantages, objects and/or purposes of the invention will be apparent to persons familiar with constructions of this general type upon reading the following specification and inspecting the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective partial view of a wall containing a door frame to which a door is attached with a continuous gear hinge assembly constructed in accordance with and embodying the present invention. 
         FIG. 2  is a top plan view of a portion of the gear hinge assembly of  FIG. 1 . 
         FIG. 3  is an elevational view of a portion of the gear hinge assembly of  FIG. 1 . 
         FIG. 4  is a perspective view of the bearing of the gear hinge assembly of  FIG. 1 . 
         FIG. 5  is a rear perspective view of the bearing of the gear hinge assembly of  FIG. 1 . 
         FIG. 6  is an elevational cross-sectional view of a spring plunger that may be used with the door assembly of  FIG. 1 . 
         FIG. 7  is a perspective view of a portion of a stall door assembly including the gear hinge assembly of  FIG. 1  and the spring plunger of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the portion of the gear hinge assembly embodiment as oriented in  FIG. 3  with the front of the gear hinge assembly generally extending out of the page. However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings and described in the following description are exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
     As shown in  FIG. 1 , the door assembly may include a door jamb  2 , a door  4 , and a lengthwise gear hinge  10 . The gear hinge  10  includes a first hinge member  12 , a second hinge member  14 , a hinge cap  16 , and one or more bearings  18  (see  FIGS. 2-3 ). 
     Referring now to  FIGS. 2-3 , the first hinge member  12  includes an elongated leaf  20  and one or more gear segments  22  which are attached to the leaf  20 . The gear segment  22  is in the shape of an arc in cross-section and includes gear teeth  24  extending from the convex edge of the gear segment  22 , and a cylindrically shaped surface  26  at the concave side of the gear segment  22 . 
     The second hinge member  14  is essentially a mirror image of the first hinge member  12 , but with gear teeth positioned to mesh with the gear segment  22 . Accordingly, the second hinge member  14  has an elongated leaf  28  and one or more gear segments  30  which are attached to the leaf  28 . The gear segment  30  is in the shape of an arc and includes gear teeth  32  extending from the convex side of the gear segment  30 , and a cylindrically shaped surface  34  at the concave side of the gear segment  30 . 
     The gear segments  22  and  30 , including the gear teeth  24 ,  32 , of the first hinge member  12  and second hinge member  14 , respectively, are sized and shaped to mesh with one another and allow pivoting rotation of one or both of the hinge members with respect to each other and with respect to the hinge cap  16 . The hinge cap  16  includes a base wall  36 , opposing side walls  38  extending from the base wall  36 , and opposing rod-like members  40  each connected to a side wall  38 . The walls  36 ,  38  and members  40  together create an inner channel  41 . The rod-like members  40  are preferably substantially cylindrical in shape, and are sized and shaped to engage with the cylindrically-shaped surfaces  26 ,  34  of the first hinge member  12  and the second hinge member  14 . The respective rod-like members  40  are spaced apart enough such that the gear teeth  24 ,  32  may mesh with one another between the rod-like members  40  and the gear segments  22 ,  30  may pivot about the rod-like members  40 . 
     As shown in  FIG. 3 , the first hinge member  12  has spaced cutout portions  42  and the second hinge member  14  has spaced cutout portions  44 . The cutout portions  42  and  44  are preferably mirror images to one another and are spaced equally along the longitudinal axis of the gear hinge  10  such that the edges of the cutout portions match longitudinally. Edges  46  define the cutout portions  42  of the first hinge member  12 . The edges  46  may be any shape or configuration, but as shown are horizontal and vertical edges leading to the gear segments  22 . Likewise, edges  48 , which define the cutout portions  44  of the second hinge member  14 , may be any shape and configuration, but as shown are horizontal and vertical flat edges leading to the gear segments  30 . 
     The gear segments  22  have upper edge surfaces  50  and lower edge surfaces  51 . The upper and lower edge surfaces  50 ,  51 , specifically in the area of the gear teeth  24 , are preferably not perpendicular to the longitudinal axis of the gear hinge assembly  10 . More preferably, the upper and lower edge surfaces  50 ,  51  are not planar, but have a helical shape, rotating to the left as the edges extend toward the bearing  18 , as the gear hinge  10  is oriented in  FIG. 3 . The upper edge surfaces  50  face generally downwardly, as the hinge assembly is oriented in  FIG. 3 . The edges  50  adjoin the upper portion of the substantially horizontal edge  46  and extend downwardly moving rearwardly. Likewise, the bottom edge surfaces  51  of the gear segment  22  adjoin the bottom portion of the horizontal edge  46  and extend upwardly as they extend rearwardly. The gear segment  30  has mirror image edge surfaces  52 ,  53 , with respect to the edge surfaces  50 ,  51  of the gear segment  22 , in the area of the gear teeth  32 . Thus, the edges  52  adjoin the upper portion of the edges  48  and extend downwardly as they extend in the rearward direction, and the edges  53  adjoin the lower portions of the edges  48  and extend upwardly as they extend in the rearward direction. The edges  50 - 53  mate with the end edge surfaces of the bearings  18 , which are discussed in detail below. 
     As shown in  FIG. 3 , the bearings  18  fit within the matching cutout portions  42 ,  44 , and are positioned to engage with the edge surfaces  50 - 53  of the gear segments  22 ,  24 . The bearings  18  each include an outer member  54 , an inner member  56 , and a medial portion  58  which connects the outer member  54  to the inner member  56  (see  FIGS. 4-5 ). The inner member  56  resides entirely within, or substantially entirely within, the inner channel  41  of the hinge cap  16  when the gear hinge  10  is assembled. The outer member  54 , inner member  56 , and medial portion  58  together define a first channel  60  and a second channel  62 . Both channels  60 ,  62  are preferably substantially cylindrically shaped and are each shaped and sized to receive a portion of a rod-like member  40  of the hinge cap  16 . 
     The outer member  54  terminates longitudinally in end edges  64 ,  70 . The end edge  64  has a generally flat surface that is substantially perpendicular to the longitudinal axis of bearing  18 , and thus also substantially perpendicular to the longitudinal axis of the gear hinge assembly  10 . The inner member  56  and medial portion  58  together define two opposing non-perpendicular surfaces at each end edge of the bearing block  18 . The surfaces  66 ,  68  at a first end abut one another, and are preferably mirror images of one another. The end edge surfaces  66 ,  68  also abut the outer member end edge surface  64 . It is contemplated that the inner member  56  and the medial portion  58  could define a single surface or more than two surfaces at each end edge. The opposing end of the bearing block  18  preferably has identical end edge surfaces. Thus, the end edge surface  70  of the outer member  54  of the bearing block  18  is substantially perpendicular to the longitudinal axis of the bearing block  18 . In addition, the opposing end edge preferably has a first end edge surface  72  and a second end edge surface  74 , both defined by the inner member  56  and the medial portion  58 , and both of which are preferably substantially non-perpendicular to the longitudinal axis of the bearing block  18  and when installed to the gear hinge assembly  10 . 
     The non-perpendicular end edge surfaces  66 ,  68 ,  72 ,  74  are preferably not flat, more preferably tapered, and most preferably helical in shape. The helical end edge surfaces  66 ,  68 ,  72 ,  74  have a change in elevation per rotation of between about 0.0625 inches per 180° (approximately 0.000347 inches per degree) to about 0.875 inches per 180° (about 0.00486 inches per degree). Most preferably, the change in elevation per rotation is about 0.300 inches per 180° (0.00167 inches per degree). The “elevation” is the distance that the end edge surface extends in the direction of the longitudinal axis of the bearing block  18 , an example of which is depicted by the letter A in  FIG. 5 . The end surfaces  50 ,  52  of gear segments  22  and  24 , respectively, are mirror images with respect to the end edge surfaces  66 ,  68 ,  72 ,  74 , as shown in  FIG. 4 . In such a configuration, when installed as part of a door, the door will automatically close due to gravity and the helical nature of the end edges of both the gear segments  22 ,  24 , and the edge surfaces  66 ,  68 ,  72 ,  74  of the bearings  18 . 
     The door assembly may also include a spring plunger  80 . The spring plunger  80  is used to hold an automatically closing door open a desired amount. An embodiment of such a spring plunger is shown in  FIG. 6 . 
     The spring plunger  80  includes a housing  82  which has threads  84  on its exterior. The housing has a hollow interior  86 . A coil compression spring  88  resides within the hollow interior  86 . At one end of the housing  82  is a plunger member  90 . The plunger member  90  includes an inner cylindrical member  92 , which resides within the hollow interior  86  and has an outer diameter that is slightly smaller than the diameter of hollow interior  86 . Connected to the inner cylindrical member  92  is an outer member  94 , at least a portion of which is disposed outside of the housing when the spring plunger  80  is in the fully extended state. The spring plunger also may include a patch  96 , preferably made of a material such as a nylon, for extra stability when the spring plunger is attached to another item. 
     The spring plunger  80  may be attached to either the door jamb  2  or the door  4 , through a leaf  20  or  28  in the gear hinge  10 , positioned in such a way to contact the other of the door jamb  2  or door  4  when the door  4  is being closed.  FIG. 7  shows an embodiment with a spring plunger  80  attached to an edge of a door  4 . In this embodiment, which includes the gear hinge assembly  10  described above, the door  4  will automatically move toward the closed position, but will remain open a desired amount (determined by the length of the plunger outer member  94 ), such as 15° to 20° from the closed position. A user can easily close the door, as only a small force is needed to overcome the biasing force of the coil compression spring  88 .