Patent Publication Number: US-6209172-B1

Title: Access door hinge arrangement for meter box cover

Description:
FIELD OF THE INVENTION 
     The present invention pertains to an improved hinge connection between an access door and a panel or cover member and is particularly adapted for a hinge connection between an access door and a utility meter box cover. 
     BACKGROUND 
     There are various structures wherein a hinge connection is required between a panel, cover member or similar structure and an access door in the panel or cover member and wherein the hinge connection is, desirably, uncomplicated and of rugged construction. One structural arrangement wherein a rugged hinge connection is desirable is between an access door and a panel or cover member for utility meter boxes. Typically, a utility meter for gas or water, for example, is disposed in a cast metal or plastic box having a removable cast metal or plastic cover which faces in a direction which provides access to the meter through a door hingedly connected to the meter box cover. In such an application the constructions of the door and the box cover are usually cast metal, such as ductile iron, or molded reinforced or non-reinforced plastic, and the parts are typically constructed wherein minimal or no machining operations are required so that the parts are finished as cast. Typical prior art meter box cover and access door arrangements include a hinge that comprises a hinge pin or rod which requires special coring or drilling operations to be used during the casting and finish fabrication of the access door or the box cover. These operations are complicated and undesirable when manufacturing inexpensive parts such as are required for certain articles including meter boxes and the like. Still further, it is desirable to provide an arrangement of a meter box cover and access door which cannot be readily disassembled from the exterior of the box cover by disconnecting the hinge structure, so that access to the meter box is only permitted through the use of a special tool or key to unlatch the access door. 
     In all events, it is desirable to provide inexpensive, rugged and uncomplicated parts for the hinge connections between access doors and associated panels or covers, such as the above-mentioned utility meter box application. It is to these ends that the present invention has been developed. 
     SUMMARY OF THE INVENTION 
     The present invention provides an improved hinge connection between an access door and a panel or cover member, particularly wherein the access door is provided as part of a utility meter box cover, for example. 
     In accordance with one aspect of the present invention, a hinge connection between an access door and a panel or cover member is provided wherein the access door includes opposed integral hinge pin members which are cast or formed as part of the door and which simplifies the fabrication of the door. The hinge pins fit within integral hinge-receiving channels or recesses which are formed as part of an integral boss structure provided as part of the panel or meter box cover, for example. 
     Still further in accordance with the invention, a hinge connection between an access door and a panel or meter box cover is provided wherein hinge pins on the access door are retained in hinge pin-receiving channels or recesses in the panel or cover member by conventional machine bolt and nut assemblies. In particular, the bolt and nut assemblies may comprise hexhead bolts which are disposed within spaced apart elongated slots formed in the panel or cover member and which are dimensioned such that the bolt heads are non-rotatable within the slots, respectively. In this way, the assembly of the access door to the panel or cover member is simplified and once the assembly is completed and the panel or cover is assembled to associated structure, the hinge-retaining bolt and nut assemblies are not removable from the exterior of the panel or cover member. 
     Those skilled in the art will appreciate that the provision of the access door-to-meter box hinge connection of the present invention is advantageous. The hinge pins are cast or molded as part of the access door and hinge-receiving channels are cast or molded integrally into the panel or cover supporting the access door. Conventional threaded fasteners are provided for retaining the hinge pins in the pin-receiving channels or recesses. Uncomplicated assembly and disassembly processes only are required. 
    
    
     Those skilled in the art will further appreciate the above-mentioned advantages and superior features of the invention upon reading the detailed description which follows in conjunction with the drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a utility meter box cover and access door including the improved hinge connection of the present invention; 
     FIG. 1A is a detail view on a larger scale showing one of the hinge pin-retaining bolt heads disposed in a slot in the utility meter box cover; 
     FIG. 2 is a perspective view of the opposite side of the meter box cover and access door showing the door in an open position and showing certain details of the hinge connection between the door and the cover; 
     FIG. 3 is a section view taken along the line  3 — 3  of FIG. 2 showing the access door in the closed position; 
     FIG. 4 is a section view taken along the line  4 — 4  of FIG. 2; and 
     FIG. 5 is a section view similar to FIG. 4 showing one of the channel-shaped recesses of the meter box cover. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     In the description which follows, like parts are marked throughout the specification and drawing with the same reference numerals, respectively. The drawing figures are not necessarily to scale and certain features may be shown exaggerated in scale or in somewhat generalized form in the interest of clarity and conciseness. 
     Referring to FIG. 1, there is illustrated, by way of example, a generally rectangular panel or cover member  10  comprising a generally planar wall part  12  and a depending peripheral flange  14 . The cover member  10  is adapted for use as a utility meter box cover and is preferably formed of cast metal, such as ductile iron. The cover member  10  includes a generally rectangular opening  16  formed therein for disposition of a hinged access door  18  shown in a closed position of the door in FIG.  1 . The access door  18  is also preferably formed of a cast metal, such as ductile iron. The access door  18  is hinged for movement between a closed position shown in FIG.  1  and an open position, as shown in FIG.  2 . The drawings are lined for metal although those skilled in the art will recognize that the members  10  and  18  may be formed or molded plastic materials also. 
     FIG. 2 illustrates further features of the cover member  10  indicating that the cover member is preferably formed with integral grid-like reinforcing ribs  13 ,  15 ,  17   a  and  17   b  to reinforce the planar wall part  12  and the peripheral flange  14 . The generally rectangular opening  16  formed in the cover  10  between the ribs  17   a  and  17   b , FIG. 2, is defined by opposed walls  16   a ,  16   b  and opposed walls  16   c  and  16   d , as indicated. Opposed integrally-formed stops  21   a  and  21   b  limit the movement of the door  18  to the closed position shown in FIG.  1 . As shown in FIG. 2, the generally planar access door  18  is also provided with integrally-formed ribbing  19 , a peripheral flange  22  and opposed integrally-formed hinge pin bosses  24   a  and  24   b . The access door  18  is preferably cast to include a planar wall part  25  integrally formed with the ribbing  19 , the peripheral flange  22  and the hinge pin bosses  24   a  and  24   b , see FIGS. 2 and 3. 
     Referring primarily to FIG. 3, the door  18  is also advantageously provided with opposed integral, generally cylindrical hinge pins  26   a  and  26   b  which project in opposite directions from the respective bosses  24   a  and  24   b . The cylindrical hinge pins  26   a  and  26   b  are coaxial and are integrally cast with the remaining parts of the door  18 . Referring also to FIG. 2, the cover member  10  is also provided with opposed integrally-cast bosses  28   a  and  28   b  which project in opposite directions from the ribs  15  and  13 , respectively, and are provided with channel-shaped recesses  30   a  and  30   b , see FIG. 3, which open in a direction away from the planar wall part  12  and are also axially aligned with each other. The channel-shaped recesses  30   a  and  30   b  are, as shown by way of example in FIG. 5, provided with semi-cylindrical base wall surfaces  31   a  and  31   b  for receiving respective ones of the hinge pins  26   a  and  26   b  journaled in the channel-shaped recesses  30   a  and  30   b , respectively. Fastener receiving bores  33   a  and  33   b , FIG. 3, open into the recesses  30   a  and  30   b  and also open into elongated slots  34   a  and  34   b  which intersect the surface  12   a  of wall part  12 . 
     As shown in FIGS. 1,  1 A,  3  and  4 , the slots  34   a  and  34   b  are each adapted to receive hex head bolts  36  having hex shaped heads  36   a , respectively. The bolts  36  project through the respective bores  33   a  and  33   b  and into the respective recesses  30   a  and  30   b , as also shown in FIG.  3 . The depths of the slots  34   a  and  34   b  are such as to provide for the heads  36   a  of the respective bolts  36  to be substantially co-planar with the surface  12   a  and the widths of the slots  34   a  and  34   b  are only slightly greater than the distance across opposed flats  36   b  of the bolt heads  36   a , see FIG.  1 A. In this way, the boltheads  36   a  may be non-rotatably disposed in the slots  34   a  and  34   b , respectively, substantially co-planar with the surface  12   a  to provide a secure hinge connection, as will be further explained hereinbelow. 
     Referring again to FIGS. 3 and 4, each of the bolts  36  is adapted to be retained in one of the respective bores  33   a  and  33   b  by a generally cylindrical washer  37  and hex nut  38 , as shown. Alternatively, the nuts  38  can have integral washer faces, if desired. The diameter of each washer  37  is greater than the width of the recesses  30   a  and  30   b , respectively, so that, when the bolts  36  are assembled to their respective washers  37  and hex nuts  38 , as shown in FIGS. 3 and 4, the machine bolt assemblies so formed are adapted to retain the hinge pins  26   a  and  26   b  in the recesses  30   a  and  30   b . In this way, an uncomplicated but advantageous hinge connection is formed between the cover member  10  and the door  18 . 
     Accordingly, the door  18  may be assembled to the meter box cover  10  by projecting the door through the opening  16  from the side of the cover which includes the bosses  28   a  and  28   b  with the integral hinge pins  26   a  and  26   b  aligned with the recesses  30   a  and  30   b . With the door  18  generally in the position shown in the drawing figures, the hex head bolts  36  may be projected through the bores  33   a  and  33   b  while the washers  37  and hex nuts  38  are assembled to the bolts and tightened to retain the hinge pins  26   a  and  26   b  within the recesses  30   a  and  30   b , as shown. The door  18  is now free to be moved between the open position shown in FIG.  2  and the closed position shown in FIGS. 1 and 3, at will. Thanks to the configuration of the slots  34   a  and  34   b  for receiving the bolt heads  36   a , respectively, the bolts  36  may be tightened without applying a tool to the bolt heads  36   a  and with the box cover member  10  applied to a meter box or similar structure, access to the bolt heads for purposes of disassembling the door  18  from the cover  10  may not be carried out. 
     Moreover, by providing the door  18  with the opposed integrally-cast hinge pins  26   a  and  26   b , more complicated casting and possibly machining operations to provide the hinge connection between the door and the cover are obviated. In fact, the assembly of the cover  10  and the door  18  may not require any machining operation except, of course, for fabrication of the bolts  36  and nuts  38 . Accordingly, the recesses  30   a  and  30   b , the bores  33   a  and  33   b , and the slots  34   a  and  34   b  may all be cast to their final dimensions. The spacing of the bolt receiving bores  33   a  and  33   b  is, as shown in FIG. 3, such as to provide only minimum lateral movement of the door  18  in the opening  16 , which movement is substantially precluded by the dimensional relationships between the door and the opening  16 . The bolt heads  36   a  may comprise other geometries, such as square or octagonal, for example, rather than conventional hexagonal shapes, as shown. 
     The construction and operation of the hinge arrangement for a door to a panel or cover member in accordance with this invention is believed to be readily understandable to those of ordinary skill in the art based on a reading of the foregoing description in conjunction with the drawing. Although a preferred embodiment of the invention has been described in detail herein, those skilled in the art will also recognize that various substitutions and modifications may be made to the invention without departing from the scope and spirit of the appended claims.