Abstract:
A ring-type meter lock including a resilient ring, first and second ends on the ring, a lock housing on the first end, a first slot in the lock housing, a latch unit in a threaded bore in the lock housing, the latch unit consisting of a threaded plug and a stem slidably mounting a latch with a spring between the plug and the latch which biases the latch into the first slot, an apertured tongue on the second end of the ring enterable into the first slot, at least one second slot in the tongue for receiving the spring-biased latch, and a key-receiving configuration on the threaded plug.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     The present invention relates to an improved ring-type meter lock. 
     By way of background, there are numerous types of ring-type meter locks in existence. However, many of these types are relatively complex, or require a key to both lock and unlock them or cannot utilize different key-receiving configurations. 
     BRIEF SUMMARY OF THE INVENTION 
     It is one object of the present invention to provide a ring-type meter lock which is relatively simple in construction. 
     Another object of the present invention is to provide an improved ring-type meter lock which can be placed in a locked condition without the use of a key. 
     A further object of the present invention is to provide an improved ring-type meter lock in which the key-receiving configuration can be changed in a simple and expedient manner. 
     Another object of the present invention is to provide an improved ring-type meter lock which is of a construction wherein the key-receiving configuration, although removable, is maintained in position by an interference fit which, in turn, requires a relatively high torque to move it to an unlocked position, thereby enhancing the security against unauthorized unlocking. Other objects and attendant advantages of the present invention will readily be perceived hereafter. 
     The present invention relates to a ring-type meter lock comprising a ring, first and second ends on said ring, a lock housing on said first end, a slot in said lock housing, a latch unit in said lock housing, a latch on said latch unit enterable and withdrawable from said slot, an apertured tongue on said second end enterable into said slot, at least one slot in said tongue receiving said latch, and a key-receiving configuration in said latch unit. 
    
    
     The various aspects of the present invention will be more fully understood when the following portions of the specification are read in conjunction with the accompanying drawings wherein: 
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     FIG. 1 is a front elevational view of an electric meter mounting the improved ring-type meter lock thereon; 
     FIG. 2 is a fragmentary side elevational view taken substantially in the direction of arrows  2 — 2  of FIG. 1; 
     FIG. 2A is a reduced fragmentary cross sectional view of the side of the ring taken substantially along line  2 A— 2 A of FIG. 2; 
     FIG. 3 is a fragmentary cross sectional view taken substantially along line  3 — 3  of FIG. 1; 
     FIG. 4 is a fragmentary cross sectional view taken substantially along line  4 — 4  of FIG. 1; 
     FIG. 5 is a plan view of the ring-type meter lock in a locked condition in solid lines and in unlocked condition in dotted lines; 
     FIG. 5A is a fragmentary rear view of the ring-type meter lock in a locked condition taken substantially in the direction of arrows  5 A— 5 A of FIG. 3; 
     FIG. 6 is an enlarged cross sectional view taken substantially along line  6 — 6  of the solid lines of FIG. 5; 
     FIG. 7 is an enlarged fragmentary front elevational view showing the lock components of the ring-type meter lock in an unlocked condition; 
     FIG. 8 is a fragmentary perspective view of the rear of the lock structure of the ring-type meter lock in an unlocked condition; 
     FIG. 9 is an enlarged cross sectional view taken substantially along line  9 — 9  of FIG. 7; 
     FIG. 9A is a view of the lock structure taken substantially in the direction of arrows  9 A— 9 A of FIG. 7; 
     FIG. 10 is a fragmentary cross sectional view of the lock structure taken substantially along line  10 — 10  of FIG. 9 with parts omitted; 
     FIG. 11 is a plan view of the latch unit; 
     FIG. 12 is an end view of the latch unit taken substantially in the direction of arrows  12 — 12  of FIG. 11; 
     FIG. 13 is a cross sectional view of the latch unit taken substantially along line  13 — 13  of FIG. 11; 
     FIG. 14 is a cross sectional view similar to FIG. 9 showing the latch unit and tongue in an open condition; 
     FIG. 15 is a cross sectional view similar to FIG. 14 but showing the tongue entering the housing; 
     FIG. 16 is a cross sectional view similar to FIG.  15  and showing the tongue in a locked condition; 
     FIG. 17 is a view similar to FIG. 16 but showing the latch in a retracted condition and the tongue released therefrom; 
     FIG. 18 is a perspective view of the key used to unlock the ring-type meter lock; 
     FIG. 19 is a perspective view of a ring-lock key guide; 
     FIG. 20 is a cross sectional view taken substantially along line  20 — 20  of FIG. 19; and 
     FIG. 21 is a fragmentary view, partially in cross section showing the key guide installed in the front portion of the lock housing. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The improved ring-type meter lock  10  (FIG. 5) is shown in FIGS. 1-4 as being mounted on a meter  11  having a transparent globe  12  removably secured thereto by meter lock  10 . 
     The ring-type meter lock  10  (FIG. 5) includes a curvilinear resilient channel-like ring  13  having a leg or side  14  of substantially uniform width throughout its circumference and a leg  15  connected to leg  14  by web  17 . Leg  15  includes two large curvilinear portions  19  and  20  and a plurality of spaced shorter circumferential portions  21  with shorter side portions  22  therebetween. A shorter side portion  23  separates side portions  19  and  21  and a shorter side portion  24  separates side portions  20  and  21 . 
     In a locked condition (FIGS. 3 and 4) side portions  19 ,  20 ,  21 ,  22 ,  23  and  24  engage flange  25  at the outer end of annular portion  27  (FIGS. 2-4) which extends outwardly from the face  29  of meter  11 . Leg or side  14  engages side  30  of annular rim  31  of globe  12 , and side  32  of flange  25  bears against side  33  of globe rim  31 . 
     A lock housing  34  is mounted on end  35  of resilient ring  13 , and a tongue  37  is mounted on the opposite end  39  of resilient ring  13  (FIG.  8 ). The lock housing  34  includes a front portion  40  and a rear portion  41 . The rear portion  41  of housing  34  (FIGS. 5A and 8) is welded to end  35  of ring  13  at  42  on flange  43 , and flange  44  of end portion  35  is received in annular groove  45  which is located between front housing portion  40  and rear housing portion  41 . A front plate  47  includes flanges  49 ,  50  and  51  which extend perpendicularly thereto, and the outer ends of flanges  49 ,  50  and  51  are welded to flange  43  of end portion  35  at  52 ,  53  and  54 , respectively. The front plate  47  includes a circular cutout  55  (FIGS. 6,  7 ,  9  and  10 ) into which the front portion  40  of housing  34  fits. 
     The tongue  37  is mounted on end  39  of ring  13  in the following manner. A portion  57  (FIGS. 6,  8  and  9 ) of tongue  37  fits through a slot  59  in ring end  39  and is welded thereto at  60 . Tongue  37  also includes a substantially perpendicular portion  61  which extends across the rear of ring end  39 , and it includes a portion  62  which extends substantially parallel to latch  37  and a portion  63  which is substantially parallel to portion  61 . An aperture  64  is located in latch portion  62 . Tongue  37  also includes two slots  65  and  67 . 
     A plunger-type latch unit  69  (FIGS. 9,  11  and  13 ) is movably positioned in housing  40 . Latch unit  69  includes a threaded plug  70  which is threaded into tapered tapped bore  71  of housing  40 . The tapered threaded bore provides security against the unauthorized removal of plug  70  because the threaded connection between the plug  70  and the tapered bore  71  creates an interference fit which requires a large torque to undo. A stem  72  is threaded into plug  70  and the head  73  (FIG. 13) of stem  72  is slidably received in bore  74  of latch head  75  which has ratchet teeth  77  and  79  thereon. A coil spring  80  biases plug  70  and latch head  75  apart (FIG.  13 ). Latch head  75  (FIG. 10) is of substantially square cross sectional configuration, and it is slidably secured within substantially square bore  81 . As can be seen from FIG. 9, the portion  71  of bore in housing  40  is threaded and the portion  81  of the bore is substantially square. Thus, when the latch unit is inserted into the bore, the plug  71  will reach its limit of inward movement when it reaches the unthreaded portion  81 . At this time the latch unit will occupy the position shown in FIG. 9 because of the manner in which the various parts are proportioned, and the head  73  of stem  72  will be in the position shown in FIG.  13 . It will be appreciated that the latch head  75  and bore  81  can be of any noncircular shape as long as ratchet teeth  77  and  79  will be maintained in the proper orientation to be received in tongue slots  67  and  65 , respectively. 
     The ring  13  can be placed in a locked condition without the use of a key. As noted above, ring  13  is resilient, and when it is in an unlocked condition, the end carrying the tongue  37  will be biased to the dotted line position of FIG.  5 . Thus, the ring  13  will be expanded so that it can be mounted about the meter flange  25  and globe rim  31  as described above relative to FIGS. 3 and 4. Thereafter, the end of ring  13  carrying tab  37  is moved from its dotted line position in FIG. 5 to its solid line position against the resilience of the ring so that tongue  37  will enter slot  82  (FIGS. 8,  9 ,  9 A) of housing portion  41 . The beveled tip  83  (FIG. 9) of tongue  37  will ride along the inclined faces  84  and  85  of teeth  77  and  79 , respectively, as tongue  37  is guided between walls  87  and  89  of slot  82 . As the tongue  37  moves against teeth  77  and  79 , the latch head  75  will move inwardly into square bore portion  81  against the bias of spring  80 . This position is depicted in FIG.  15 . When the tongue reaches a position wherein slots  65  and  67  therein are abreast of teeth  77  and  79 , respectively, spring  80  will bias latch head  75  from its retracted position of FIG. 15 into slots  65  and  67  of tongue  37 . In the locked position, the tongue  37  cannot be withdrawn because the sides  90  and  91  (FIG. 9) of tongue slots  65  and  67 , respectively, will be in abutting relationship with sides  92  and  93 , respectively, of teeth  79  and  77 , respectively. 
     When tongue  37  is in the above-described locked position with teeth  77  and  79 , flanges  94  and  95  (FIG. 9) of ring end  39  will occupy the positions shown in FIG. 6 wherein flange  95  is received within annular groove  45  and flange  94  is located at the rear of rear housing portion  41  in opposition to flange  43  of ring end  35 . At this time opening  64  in tongue portion  62  will be aligned with slot  97  of front plate  47  so that a wire-type of locking seal can be placed through slot  97  and opening  64  to prevent unlatching of the lock without destroying the seal. 
     At this point it is to be noted that the latch may be engaged with only tooth  77  being received within slot  65  of tongue  37 . In this event also there will be an alignment of slot  97  in face plate  47  with opening  64  of tooth portion  62  for receiving a wire-type of seal. It will be appreciated that when the foregoing single tooth locking relationship is effected, the diameter of ring  13  will be slightly larger in its locked position than when both teeth  77  and  79  are positioned in tongue slot  67  and  65 , respectively. Therefore, the ring can fit onto a slightly larger annular rim  31  of a globe than when both teeth of the latch head are in slots  65  and  67 . 
     The ring-type meter lock  10  is unlocked to its position of FIG. 17 from its locked position of FIG. 16 by utilizing a key  99  having a curvilinear ridge  100  (FIG. 18) at the end of stem  101 . Curvilinear ridge  100  is of a configuration to mate with curvilinear groove  102  (FIGS. 12 and 13) in the face  103  of threaded plug  70 . When threaded plug  70  is threaded outwardly in threaded bore  71  from the position of FIG. 16 to the position of FIG. 17, the head  73  (FIG. 13) of stem  72  will bear against end wall  104  (FIG. 13) to pull latch head  75  into substantially square bore  81  to the position shown in FIG. 17 wherein the natural resilience of ring  13  will cause tongue  37  to be withdrawn from housing  34  to the position shown in dotted lines in FIG. 5, and when the ring  13  is in the dotted line position of FIG. 5, it can be removed from engagement with the globe and the meter so that the globe  12  can be removed from its mounted position. In order to reset the latch unit to receive tongue  37  in a locked condition, the plug  70  is threaded back from its position of FIG. 17 to its position of FIG. 14 whereupon latching engagement will be effected between tongue  37  and one or more teeth  77  and  79  in the manner described above when tongue  37  is inserted into slot  82 . The latch unit  69  can be replaced easily because of the fact that it can be removed from its bore by merely unscrewing it completely, rather than partially as in FIG.  17 . This provides the option of replacing the entire latch unit with a plug having a different key-receiving configuration. Also, if desired, the plug  70  itself can be unscrewed from stem  72  and replaced with a plug having a different key-receiving configuration. 
     In FIGS. 19,  20  and  21  a ring-lock key guide  110  is shown which fits into the front portion  40  of lock housing  34 . More specifically, the key guide  110  includes a hollow cylindrical body  111  having an annular collar  112  thereon which has a tapered upper surface  113 . Collar  112  is received in annular groove  114  of front portion  40  of lock housing  34 . In this respect, the tapered surface  113  of collar  112  slides along the inclined surface  115  of housing portion  40 , and when collar  112  reaches groove  114 , it snaps into place with the rear annular edge  117  of collar  112  bearing against the wall, not numbered, of groove  114 , to thereby retain collar  112  in groove  114 . 
     The ring-lock key guide  110  is fabricated of flexible plastic material which permits the collar  112  to distort during the installation process, and it thereafter snaps back into its annular shape to retain the ring-lock key guide  110  in position. 
     The ring-lock key guide performs a plurality of functions. In this respect, it acts as a guide for the stem  101  of key  99  (FIG.  18 ). Also, it prevents the plug  70  from falling out when it is unscrewed. Additionally, there are two diametrically opposed slots  119  and  120  in cylindrical body  111  which can be used to receive the wires of a seal of the type having the wire thereof extending through slots  119  and  120  with the ends of the wires fastened in a seal member, so that the portion of the wire extending across the opening prevents an effective tool from being passed through the ring-lock key guide  110  without the wire breaking. Also, if desired the wire can also extend through opening  64  in tongue portion  62  and slot  97  in front plate  47 , as discussed above. 
     While preferred embodiments of the present invention have been disclosed, it will be appreciated that it is not limited thereto but may be otherwise embodied within the scope of the following claims. 
     SEQUENCE LISTING 
     Not applicable