Abstract:
A hinge apparatus allows a door to be opened from either the left or right side. The apparatus has a guide member defining an guide channel that interacts with a hinge pin. Preferably, the hinge pin is attached to the door and the guide member is attached to a frame having an opening that is covered by the door. The hinge pin can slide along the guide channel like a latch pin or rotate within the channel like a conventional hinge pin.

Description:
TECHNICAL FIELD  
       [0001]     This invention relates to a hinge apparatus for use with doors on furniture and fixtures. In particular, the invention relates to a hinge system for opening a door from either side and having hinge units with hinge pins that readily engage or disengage either side of the door by sliding action.  
       BACKGROUND OF THE INVENTION  
       [0002]     Traditionally, hinges are permanently attached to doors, allowing the door to be opened only on the side opposite the hinge, which limits the usefulness and convenience of the door. Nearby walls or furniture can obstruct the opening of the door to one side. Also, personal preferences may differ on which side of the door to open. Thus a door that can be opened from either side would be preferable for some uses.  
         [0003]     Over the years, a number of devices have been developed to allow a door to be opened from either the left or right side. U.S. Pat. No. 5,530,992, issued to Baermann on Jul. 2, 1996, discloses a device for use primarily on a refrigerator. The device makes use of an elongated hinge rod attached to the door and mating magnetized receivers mounted on the frame along the length of the hinge rod. Magnetic attraction between the receivers and the hinge rods holds the door in place when closed. Mechanical interlocks are also used to retain the hinge rod in the receiver when the hinge rod is rotated in the receiver. These interlocks do not come into effect until the hinge is rotated, i.e. when the door is opened in the normal fashion, so it is possible for the door to be pulled off the cabinet when in a closed position. This means that the door can accidently fall off the frame. Accidental opening becomes more likely as the receivers&#39;s magnetic strength decreases with age, until the door may fall off during a normal opening operation.  
         [0004]     Other devices have attempted to avoid the drawback of accidental release of the door in the closed position. However, these devices generally require the operation of a release mechanism such as a handle or button before releasing the side of the door to be opened. These mechanisms add to the cost and the parts count of the device, and add more steps to the opening procedure. If the release mechanisms are not located in an obvious place, they can unintentionally confuse a new user and even prevent them from opening the door.  
         [0005]     A need remains for a latching hinge device that allows a door to be opened from either side. The device should prevent the door from being removed when in a closed position without the need for buttons, rotating handles, or similar release mechanisms. A device that can be used like a traditional simple hinge, and can be constructed inexpensively with a minimum of parts is also desired.  
       SUMMARY OF THE INVENTION  
       [0006]     In general, an apparatus having the desired features and advantages is achieved by a plurality of hinge units, wherein each hinge unit includes a hinge pin and a guide member having a guide channel defined in the guide member. The guide channel has an opening adapted to receive the hinge pin transversely and a closed distal end at the opposite end of the guide channel. The hinge pin can move laterally along the length of the guide channel and rotate about its axis while in the guide channel. Thus, the combination of the guide member and the hinge pin allows the hinge unit to perform the functions of both a conventional hinge and a sliding latch. The guide channel can take a number of different shapes, being curved, straight or various combinations of curved and straight sections.  
         [0007]     In a preferred embodiment, the door initially must move transversely from a closed position until the hinge pin on the side to be opened can exit its respective guide channel At this point, the door is opened by rotating the door about the opposed hinge pin, just like a conventional hinged door. Typically, the door moves transversely without significant rotation. However, in some embodiments the door will rotate slightly during its transverse motion. Preferably, the hinge units employ mechanical interlocks to prevent the hinge pins still in the guide channels from moving laterally while the door is being rotated.  
         [0008]     Additional features and advantages of the invention will become apparent in the following detailed description and in the drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is a front elevation of a hinge apparatus according to the invention, as it appears when in use with a cabinet and door.  
         [0010]      FIG. 2  is a detail view of one of the hinge units seen in  FIG. 1 .  
         [0011]      FIG. 3  is a partially cross-sectional detailed top plan view of the hinge unit and guide member as seen along lines  3 - 3  in  FIG. 1 .  
         [0012]      FIG. 4  is a partially cross-sectional top plan view of the invention with the door closed, as seen along lines  4 - 4  in  FIG. 1 .  
         [0013]      FIG. 5  is another top plan view of the invention, with the door positioned so that the left side hinge pins are at the point of initial engagement with their respective guide member&#39;s guide channel.  
         [0014]      FIG. 6  is a partially cross-sectional view of an embodiment of the guide member, showing lateral retaining means for holding the door in a closed position.  
         [0015]      FIGS. 7 and 8  are cross-sectional top plan views as in  FIGS. 4 and 5  of an embodiment with different guide members.  
         [0016]      FIG. 9  is a detail view of an alternative embodiment of a typical hinge pin and support member.  
         [0017]      FIGS. 10 and 11  are a cross-sectional top plan view and front elevation, respectively, of the preferred embodiment of the hinge unit having optional mechanical interlocks.  
         [0018]      FIGS. 12 and 13  illustrate the operation of the mechanical interlocks. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]     In the various drawings, equivalent elements are given the same reference numbers. Also, the drawing figures are not necessarily to scale and in certain views proportions may have been exaggerated for clarity.  
         [0020]      FIG. 1  shows the preferred embodiment of the hinge apparatus  11  of the invention as installed on a cabinet  13  with a door  15 . The hinge apparatus  11  includes a number of hinge units  17 ,  19 ,  21 , and  23 , with the left side hinge units  17  and  21  being installed as mirror images of the right side hinge units  19  and  23 . Preferably, the hinge units  17 ,  19 ,  21 , and  23  are identical to minimize the number of different parts that need to be manufactured. The hinge units are symmetrical about a horizontal centerline, so that each unit can be used on either the left or right side of the door  15  simply by rotating the unit by 180 degrees.  
         [0021]     As seen in  FIGS. 2 and 3 , the hinge units  17 ,  19 ,  21 , and  23  each comprise a hinge pin  25  and a guide member  27 . The hinge pin  25  is preferably attached to the door  15  by means of a support member  29  having a base  31  and support arms  33  and  35  that hold the hinge pin  25  offset from the base  31 .  
         [0022]     As shown, the guide member  27  has a base  28  on which are mounted two upright sections  37  and  39 , which can be replaced by a single section spanning the entire volume occupied by the upright sections  37  and  39  and the empty space between them. Identical guide channels  41  are defined in the upright sections  37  and  39 , which interact with the hinge pin  25  in a manner to be discussed later. Because the weight of the door  15  is borne by the guide members  27 , materials and dimensions should be selected to provide sufficient strength while still providing low contact friction and a close fit with the hinge pin  25  and the support arms  33  and  35 . Additional guide arms  38  and  40  can also be used. These arms provide the means to help keep the hinge pins  25  from twisting in the guide channels  41 .  
         [0023]     The guide channel preferably is substantially arcuate in shape, but it can be partially or totally linear. As shown, the guide channel  41  forms a semicircular arc, but it can be noncircular in shape, such as a logarithmic, hyperbolic, sinusoidal, or other curve, or a combination of one or more of such curves. The arcuate section(s) preferably all curve in the same direction, i.e. there are no S-shaped sections, but this is not a necessary feature.  
         [0024]     The guide channel  41  has an opening  43  for admitting the hinge pin  25  in a transverse relation to the guide channel. The opening  43  is preferably ‘flared’ to permit the hinge pin  25  to enter the guide channel  41  easily even if the pin is off-center in relation to the guide channel. However, the width of the guide channel  41  preferably narrows quickly, so that the width of the guide channel  41  from at least the channel midpoint  44  (see  FIG. 5 ) to the end  45  of the guide channel  41  distal to the opening  43  is just larger than the diameter of the hinge pin  25 . This width is selected to minimize play when the hinge pin  25  is located at the distal end  45  of the guide channel  41 . Preferably, the distal end  45  is semicircular to match the hinge pin  25 .  
         [0025]      FIGS. 4 and 5  illustrate the basic operation of the hinge apparatus  11 .  FIG. 4  shows the various elements when the door  15  is closed. The hinge pins  25  are located substantially at the midpoints  44  of their respective guide channels  41 . To open the door on the left side, a user would grasp the doorknob  47  nearest the left side hinge units  17  and  21  and pull the doorknob  47  away from the frame  13 . Preferably the doorknob is also pulled toward the center of the door  15  to ensure that the hinge pins  25  are biased toward the guide channel openings  43 . The hinge pins  25  will move along the guide channels  41  until the hinge pins  25  in the right side hinge units  19  and  23  reach the distal ends  45  of their guide channels  41 . At this point, the hinge pins  25  in the left side hinge units  17  and  21  will be located at the openings  43  of their guide channels  41 , as shown in  FIG. 5 . Applying a force generally in the direction of the arrow  49  in  FIG. 5  will cause the door  15  to rotate about the hinge pins  25  in the right side hinge units  19  and  23  in the same manner as a conventionally hinged door. To close the door  15 , the process is reversed. It can be seen that as the door  15  goes from the closed position of  FIG. 4  to the position in  FIG. 5 , the door  15  moves laterally in an arcuate path across the face of the cabinet  13 , with the door  15  remaining substantially parallel to the face of the cabinet  13 . Also, when the hinge pins  25  reach the midpoints  44  of their respective guide channels  41  as shown in  FIG. 4 , the hinge pins  25  and therefore the door  15  are at their closest approach to the cabinet  13 .  
         [0026]     In the preferred embodiment the door  15  contacts the cabinet  13  when in the closed position. Friction between the door  15  and the cabinet  13  serves to keep the door in place in the closed position. A more sophisticated lateral retaining means is depicted in  FIG. 6 . The guide member  27  is modified to include a leaf spring  53  ending in a projection  55 . The leaf spring  53  is located in the void between the guide member upright sections  37  and  39 . The projection  55  is located so that the hinge pin  25  will displace the projection  55  during its lateral movement just before the door reaches the closed position. The projection  55  and leaf spring  53  will at least partially spring back to their undisplaced configuration as the door  15  reaches the closed position. The leaf spring and projection then bias the hinge pin  25  to prohibit movement of the hinge pin back toward the guide channel opening  43 . Preferably, retaining means should be employed on both right and left side hinge units. Detents and other equivalent temporary retaining means known in the art can also be used.  
         [0027]      FIGS. 7 and 8  depict an alternative embodiment of the apparatus, wherein a resilient seal  57  is located between the cabinet  13  and the door  15  to seal the interior of the cabinet  13  against the outside environment. In this embodiment, the guide channels  41  are configured essentially as inclined linear slots. In the closed position the hinge pins  25  of both the left side hinge units  17  and  21  and the right side hinge units  19  and  23  substantially at the midpoints of the guide channels  41 . This inherently creates a gap between the door  15  and the frame  13  in which the seal  57  is located. Opening and closing the door proceeds in a similar manner as in the embodiment of  FIGS. 4 and 5 , except that there is no need to pull the doorknob toward the center of the door, as the straight-line channel guide configuration will inherently guide the hinge pin toward the opening  43 .  
         [0028]     As previously discussed, in the preferred embodiment of  FIGS. 4 and 5  the door remains substantially parallel to the cabinet as it is moved laterally. This is not the case in the embodiment of  FIGS. 7 and 8  however, where the door rotates slightly along with its lateral movement. The result is that the seal  57  is compressed to a greater extent on the side where the hinge pins  25  travel toward the distal end  45  of the guide channel  41  than it is when the door is in the closed position (see  FIG. 7 ). If this is not desired, the guide channels from the embodiment of  FIGS. 4 and 5  can be used, with the proper modifications to create the necessary gap (e.g. displacing the guide channels and/or the hinge pins).  
         [0029]      FIG. 9  shows a modification to the guide member for use when there is a gap between the cabinet and the door in the closed position, with or without the resilient seal  57 . In this embodiment, an eccentricity  59  extends from the support arm base  31  along the entire length of the base  31  on the side of the support member facing the door. The eccentricity  59  contacts the cabinet  13  when the door  15  is in the closed position. This contact helps steady the door  15  and provides friction to hold the door in the closed position, but acts over a much smaller surface area than the full contact between the door and the cabinet. This may be preferable even when a gap between door and cabinet is not necessary, but where the static friction from full contact between door and cabinet would cause the door to stick.  
         [0030]     As previously discussed, mechanical interlocks are preferably used to retain the hinge pin  25  in place laterally while the hinge pin is being rotated.  FIGS. 10 and 11  show one possible embodiment of a mechanical interlock. In this embodiment, an annular groove  61  is defined in one or both of the hinge pin support arms  33  and  35 , adjacent to the hinge pin  25  and circumscribing it. An opening  63  extends radially from the annular groove  59  out to the edge of the support member  33  or  35 . A mating interlock pin  65  is attached to the guide member  37  and  39  adjacent to the hinge pin support arm  33  and  35  and located so that the pin  65  will pass through the opening  63  as the hinge  25  enters the distal end  45  of the guide channel  41 , as shown in  FIG. 12 . Rotating the hinge  25  at the distal end will cause the interlock pin  65  to enter into and be retained by the annular groove  61 , thereby preventing the hinge pin from leaving the distal end  45  of the guide channel  41  while the door is open, as shown in  FIG. 13 . It will be apparent to a person of ordinary skill in the art that the interlock pins can be located on the hinge pin support arm with the annular grove defined in the guide member. Other mechanical interlocks known in the art can also be employed, such as the interlock shown in U.S. Pat. No. 5,530,992, issued to Baermann, the disclosure of which is incorporated herein.  
         [0031]     Another embodiment is possible, wherein the hinge pin  25  is attached to the door without additional parts, such as by cutting a notch out of the side of the door  15  and drilling mounting holes through the door  15  in the plane of the notch to hold the hinge pin  25  in the notch. While this embodiment has the advantage of fewer parts and therefore is potentially less expensive to make, it requires the door to be oversized compared to the preferred embodiment and weakens the area of the door surrounding the notch. This embodiment is also impractical when the door is designed to rotate during its lateral motion, as in  FIGS. 7 and 8 .  
         [0032]     The invention has several advantages over the prior art. The hinge apparatus can be constructed simply and inexpensively, with a minimum of different parts. It is extremely rugged and durable, and can be easily installed. It prevents the door from being accidently opened, yet requires a simple mechanical movement similar to a conventional hinged door in order to open the door. In applications where a seal is fitted between the door and the cabinet, the present invention applies sealing force on both sides of the door, which can result in a more even and secure seal.  
         [0033]     The invention has been shown in several embodiments. It should be apparent to those skilled in the art that the invention is not limited to these embodiments, but is capable of being varied and modified without departing from the scope of the invention as set out in the attached claims.