Abstract:
A restraint mechanism for limiting the angular rotation of a first and a second component which move about a common hinge comprising a restraining arm adapted to extend along a portion of the first component in the direction of the hinge and having a change of direction away from the hinge, and an attachment member for attaching the restraint mechanism to said first component.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of mechanical devices for limiting angular rotation of members connected by a hinge or pivot. 
     BACKGROUND OF THE INVENTION 
     It is often desirable to define the relationship between two members which move with respect to one another about a hinge or pivot by limiting the allowed movement. One such situation arises in the case of a box having a top attached to a base by a hinge where the top moves in relation to the base. An especially significant example is an electrical or fiber optic box which has hook type hinges for quick engagement and disengagement when the singed members are in their fully open configuration. 
     The hook type hinge is used because it makes fabrication quick and easy. The hinge consists of a rod that is captured by a corresponding U-shaped member by clicking into place when the hinge is in the fully open position. Unfortunately, the hinge is just as easily disengaged when the box is in its fully open position. 
     Moreover, care must be taken with wires that pass from the top of the box to the base when opening the box to prevent damage to the wires or cable which may have a minimum bend radius. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a restraint mechanism for limiting the angular rotation between a first component and a second component which move about a common hinge comprising a restraining arm adapted to extend along a portion of the first component in the direction of the hinge and having a change of direction away from the hinge, and an attachment member for attaching the mechanism to said first component. 
     Preferably, the mechanism includes a base from which the restraining arm originates and a retention arm originating from the opposite side of the base from the restraining arm. The retention arm has a change of direction toward the hinge to create a D-shaped configuration with the restraining arm, having an opening for accepting wires or the like within the arms of the mechanism. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The attached drawings, in which like reference characters represent like parts, are included to better illustrate the preferred embodiment of the present invention, without limiting the invention, wherein: 
     FIG. 1 is a perspective view of an electrical box suitable for use with the present invention. 
     FIG. 2 is a partial perspective view of an exemplary hinge which provides quick assembly/release at a specific angle. 
     FIG. 3 is a partial side elevation of the hinged components of a box in its fully opened configuration. 
     FIG. 4 is a perspective view of the preferred restraint mechanism of the present invention. 
     FIG. 5 is a partial side elevation of the hinged components with the preferred restraint mechanism of the present invention mounted on one of the components. 
     FIG. 6 is a side elevation of the open box with the preferred restraint mechanism of the present invention limiting the rotation of the hinged components of the box. 
     FIG. 7 is a perspective view of a box mounted on a wall with the preferred restraint mechanism of the present invention mounted thereon, said restraint mechanism holding wire exiting from the box. 
     FIG. 8 is a front elevation of the preferred restraint mechanism of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A standard electrical box  2  as shown in FIG. 1, generally made of metal or high impact plastic, has two, three (as shown) or more hinged components for access to the wires, connections and devices therein. For purposes of this description, the two components  4  and  6  which move relative to a hinge  8  will be referred to. 
     Hinges  8  for these types of electrical boxes  2  have been simplified for field assembly by providing easy attachment/release of two corresponding hinge elements  10  and  12 . As shown in FIG. 2, the first component  4  includes a first hinge element  10  formed as a U-shaped member, the opening of which fits over a rod shaped member  12  included on the second component  6 . 
     To control unwanted release of the hinge members  10  and  12  the U-shaped member  10  is positioned in such a way that it can only be released from the rod member  12  when the components  4  and  6  are in their fully open configuration, as shown in FIG.  3 . Otherwise, the open portion of the U-shaped member  10  is restricted from moving off of the rod by the closed portion of the U-shaped member  10  hitting the body of the second component  6 . 
     Of course, the particular hinge  8  is not important to the present invention. However, the restraint mechanism  20  of the present invention is particularly useful when used on a box with hinges  8  that only release at the fully open configuration. This is because the restraint mechanism  20  prohibits the components from reaching the fully open configuration when properly engaged. 
     The restrain, mechanism  20  of the present invention, as shown in FIGS. 4 and 5, includes an attachment member  22  and a restraining arm  24  for stopping the angular rotation of the first and second components  4  and  6  of the box  2 . The restraining arm  24  extends from its connection to the box  2  along a portion of the second component  6  and turns away from the hinge  8 . 
     Preferably, the turn comprises a radial bend  40  which is contained within the hinge  8  as shown in FIGS. 5 and 6. It is also preferred that the end of the restraining arm  24  extend through an arc greater than 90° to a terminal end  42 , the angle of which most preferably depending on the preferred angle of the components  4  and  6  when in the open and restrained position shown in FIG.  6 . Moreover, the arm  24  is preferably flexible to provide some give when the top  4  contacts the restraining arm  24 . 
     The preferred attachment member  22  includes two extensions  26  and  28  having opposed outwardly extending catches  30  and  32  thereon. The attachment member  22  corresponds with a receiver  14  in the base  6  of the box  2  where the catches  30  and  32  of the attachment member  22  releasably engage shelves  16  in the receiver  14 . One of the extensions  26  is placed in the receiver  14  and the restraint mechanism  20  rotated until the other extension  28  enters the receiver  14  and the catch  32  clicks over the shelf  16 . 
     Of course, any other known or later developed attachment members  8  could be used. These include such known physical connections as a receiving channel and a corresponding “T” or “L”-shaped extension where the extension slides into the channel to hold the pieces together. In such an embodiment, it does not matter whether the extension resides on the restraint mechanism  20  or on the component  6  of the box  2 . Similarly, a screw and corresponding threads can be used for the mechanism  20  to be screwed onto the box  2 . Alternatively, a snap with corresponding receptacle, a key with corresponding keyway or a dog can be used without deviating from the invention. 
     More permanent mounting can be used, including epoxy, adhesives, double sided tape and the like materials. However, it is preferred that removable means be employed to provide for later disassembly of the components  4  and  6  if desired. 
     To aid stability, the restraining arm  24  is attached to a base  34  which can rest against a wall on which the box  2  is mounted. See FIGS. 6 and 7. To further increase stability, the base  34  is preferably secured to the wall by a screw passing through a screw mounting hole  36  in the base, which is then screwed into the wall. 
     On the side of the base  34  opposite that which the restraining arm  24  is attached, a retention arm  38  preferably extends toward the terminal end of the restraining arm  24  and the hinge  8 . The retention arm  38  also preferably includes a radial bend  44  through an arc which is less than 90°, to match with the angle of the end of the arm  24 , and terminates in a terminal end  46 . 
     The retention arm  38  acts to hold wires exiting from the box  2 . See FIG.  7 . As such, there is preferably a space between the terminal ends  42  and  46  of the restraining arm  24  and the retention arm  38  to allow a technician to slip wires into the mechanism  20 . As best seen in FIG. 8, the terminal ends  42  and  46  are most preferably offset, turning in different lateral directions, to aid in the separation of the terminal ends  42  and  46  to slip a bundle of wires. 
     It is preferred that the restraint mechanism  20  be formed of unitary construction, preferably injection molded of a high impact plastic material. Suitable materials are polycarbonate or polyvinyl chloride (PVC) with polycarbonate being most preferred. 
     Variations and modifications to the invention described herein will make themselves apparent to a person skilled in the art reviewing this disclosure. All such variations and modifications are intended to fall within the spirit and scope of the present invention, limited only by the following claims.