GB2159633A

GB2159633A - A box, especially for an electric meter or the like

Info

Publication number: GB2159633A
Application number: GB08413973A
Authority: GB
Inventors: Pierre Bourrieres
Original assignee: Manufacture dAppareillage Electrique de Cahors SA
Current assignee: Manufacture dAppareillage Electrique de Cahors SA
Priority date: 1984-06-01
Filing date: 1984-06-01
Publication date: 1985-12-04
Also published as: DE3568640D1; GB2159633B; EP0168279A1; ATE41243T1; GB8413973D0; MY101459A; EP0168279B1

Abstract

A box for protecting an electric meter or similar apparatus against fraud, theft and the like comprises a hollow body (1) provided with an aperture (2) and a cover (3) adapted to close the aperture (2) of the body (1). The cover (3) carries a locking mechanism (29) operable by a key (33) and provided with a locking member (34) rotatable with respect to cover (3) between a locked position in which the member (34) engages retainers (37) of the body (1) and a release position. The locking mechanism (31) allows removal of the key (33) when the locking member (34) is in the locked position and unremovably retains the key (33) when the locking member (34) is in the release position. The box comprises spring loaded bolt means (43) for irreversibly maintaining the locking member (34) in the locked position when the locking member (34) and the retainers (37) are mutually engaged. <IMAGE>

Description

1

SPECIFICATION

A box especially for and electric meter or the like This invention relates to a box for an electric meter or the like, and more generally for any apparatus requiring protection against fraud, theft and the like.

The door or cover of such boxes may be provided with any well-known locking means such as those with a key. Fraud is theoretically prevented if the door has actually been closed and locked by means of the key.

However, the key or a master key may be stolen or imitated with the result that the box is no longer safe. Moreover, intentionally or not, the box may appear to be closed while in fact it has not been locked by means of the key. This allows fraudulent traffic between for example an electricity user and an employee, the employee being paid for -forgetting- to lock the box by means of the key.

It could be proposed to overcome this problem by providing a spring catch closing means for the door or cover instead of a key. However, any spring catch closing means is easy to fraud by obturating with a foreign object the recess intended to receive the latching member of the spring catch means. The cover may then be closed normally and remain so; however, instead of being thereafter locked in place, the cover is on the contrary easy to reopen since the latching member has been prevented from engaging the recess. Thus, a traffic similar to the above remains possible.

The object of this invention is to provide a box rendering such fraudulent traffic at least much more difficult.

According to the invention, there is provided a box, especially for an electric meter or similar apparatus needing protection against fraud, theft and the like, comprising two casing portions which are a hollow body provided with an aperture and a cover adapted to close the aperture of the body, one of the casing portions carrying a locking mechanism operable by a key and provided witha locking member movable with respect to said one casing portion between an operative position allowing engagement of a retaining means of the other casing portion and a release position, the locking mechanism being adapted to allow removal of the key when the locking member is in the locking position and to unremovably retain the key when the locking member is in the release position, and the box comprising means for substantially irreversibly maintaining the locking member in the locked position when the locking member and the retaining means are mutually engaged.

Thus, when the cover has been correctly closed and locked with the key, the employee withdraws the key. Since the key may be withdrawn only when the locking member is GB 2 159 633A 1 in the locked Position, the employee, by bringing back the key, proves that the locking member has been placed in the locked position. It might be thought that the employee could bring the locking member in the locked position while maintaining the cover away from the body. In fact, this will rarely happen because the locking member in the locked position would prevent the cover from fitting tothe body.The cover would thus remain obviously open and fraud would be too evident. Once the cover is correctly locked, the locking member is automatically and irreversibly maintained in the locked position. The cover cannot be reopened, even with the key or with a master-key. It is therefore useless to steal or imitate the key.

As mentioned above, the key is now nothing more than the evidence that the cover is correctly closed.

In a preferred embodiment, there is provided a means biasing the cover towards an open position clearing the aperture of the body. Thus, the cover cannot remain partly closed if the locking member does not engage the retaining means. Accordingly the cover is either closed and locked or wide open, rendering fraud very obvious if the employee tries to withdraw the key without having engaged the locking member and the retaining means.

Preferably, part of the means for maintaining the locking member in the locked position are carried by the said other casing portion. Thus, retention of the locking member in the locked position occurs only when the cover is fitted to the body, and may not occur while actuating the key inadvertently before said fitting.

Other features and advantages of the inven- tion will become apparent from the detailed description of a non limitative example, with reference to the attached drawings in which:

Figure 1 is a schematic perspective exploded view of a box according to the inven- tion; Figure 2 is a perspective exploded view, at an enlarged scale, of a retaining block of the body and a retaining plate of the cover; Figure 3 is a part view of the box in cross- section along a vertical plane perpendicular to the plane of the body aperture; Figure 4 is a perspective, partly sectional wiew of the securing means of the body; Figure 5 is a sectional part-view of the box along line V-V of figure 3; Figure 6 is a part view of the cover along arrow VI of figure 1 when the latch is in the release position; Figures 7 and 8 are respectively a plan view and an elevation of the latch Figures 9 and 10 are respectively a plan view and a side view of the retaining plate of the cover; Figure 11 is a sectional view of the retain- ing block of the body along line X1-Xl of 2 GB2159633A 2 1 figure 5; Figure 12 is a detail of figure 11 at an enlarged scale, also showing part of the latch cooperating with the immobilization bolt before spring catch of the latch by the bolt Figures 13 and 14 show along arrow XIII of figure 1 two stages of the latch clearing the bolt from a foreign object intended to fraudulently prevent immobilization of the latch in l 0 the locked position, the latch being shown in section along line X111- Xlil of figure 8.

As shown in figure 1, a box in accordance with the invention comprises two casing portions, i.e. a substantially parallelepipedic, hollow body 1, one larger face of which is an aperture 2, and a rectangular cover 3 adapted to close aperture 2.

The body 1 has a wall 4 opposite to the aperture 2, side walls 6, an upper, substan- tially horizontal wall 7 and a lower, substantially horizontal wall 8.

The inner face of wall 4 carries weliknown means 9 for securing an electric meter or the like apparatus needing protection against fraud. The cover 3 is provided with a window 11 allowing the electric meterto be read without opening the box. Window 11 is reinforced on the inside with a grid 12. The body 1 may be secured to a support such as the wall of a house by means of securing devices 13 one of which is seen in figures 3 and 4. Each device 13 comprises a screw 14 adapted to be screwed in the wall 16 with its head 17 on the inner face of wall 4 of body 1. The region of wall 4 which receives the head 17 is surrounded by a thin breakable connection 18 with the remaining portion of wall 4. The connection 18 is in turn surrounded by an annular wall 19 protruding towards aperture 2. The space surrounded by wall 19 is closed by a lid 21 which is secured to wall 19 by screws 22. The head 23 of said screws, which is inside the body 1, is of a known special type allowing screwing thereof by means of a screw driver, but not unscrewing.

The body 1 and the cover 3, as well as the lids 21 may be made of plastic material, connections 18 being obtained by convenient molding of said material.

The aperture 2 extends in a vertical plane.

As shown in figures 1 and 3, the upper edge of aperture 2 is provided with a downwardly opening groove 24. The two ends 26 of a spring blade 27 are secured against the upper face of groove 24. Between its ends 26, blade 27 is arcuated downwardly. The top edge of cover 3 is provided with a rib 28 adapted to fit in groove 24. The other edges of aperture 2 and cover 3 may be placed against each other so as to close aperture 2, but no means other than groove 24 and rib 28 are provided for retaining the cover 3 against the body 1, except for locking means29 in cover 3, 31 in body 1 -which will be described hereinafter. The arrangement is 130 such that blade 27 must be compressed by rib 28 for the edges of aperture 2 and those of the cover 3 to face each other and for the locking means 29, 31 to be able to coop- erate. Thus, when the locking means 29, 31 are not engaged, the cover 3 cannot be fitted to the body 1 in a stable manner, but only in such a manner that the cover 3 will slide open vertically under the effect of its own weight.

As shown in figures 1, and 5 to 8, the locking means carried by cover 3 comprise a locking mechanism 29 comprising a lock 32 actuated by a key 33 and actuating a locking member or latch 34 which is rotatable about an axis XX which is perpendicular to the plane of the aperture 2 when cover 3 closes said aperture. The latch 34 is movable between a locked position (figure 5) and a release position (figure 6) by rotation about axis XX. In the locked position, two diametrically opposed wings 36 of the latch 34 respectiveley engage two retainers 37 belonging to the locking means 31 carried by the body 1. The retainers 37 are shells which are mutually symmet- rical with respect to an axis which corresponds to axis XX when the cover 3 closes the body 1; Each shell 37 is opened towards said axis andalso on a side allowing entry of the corresponding wing 36. In the release position, the wings 36 are disengaged from the shells 37.

The lock 32 is adapted to allow withdrawal of the key 33 only when the latch 34 is in the above mentioned locked position. In the example as shown, this is obtained by the fact that the lock 32 is secured to the cover 3 near a lower shoulder 38 thereof so that one of the wings 36 (figure 6) abuts at 39 against said shoulder 38 when the latch 34 It should also be noted from figure 13 that the two short sides 48 of boss 47 are sharply inclined with respect to each other.

As shown in figure 6, the plate 41 carries two pegs 49 which point towards the body 1 and are disposed on each side of the path of bolt 43 on the plate 41 between the phantom position and the hole 42. As seen in figures 13 and 14, during rotation of the latch, the boss 47 travels between the pegs 49 which are so adapted as to clear the boss 47 of any foreign object such as a U- shaped member 51 which could have been placed on boss 47 to prevent operation of bolt 43 and thus prevent spring catching of the latch34 by the bolt 43, with a view to rendering the key 33 operative to reopen the box after apparently correct locking thereof. The distance between the pegs 49 is substantially equal to the broadest transverse dimension ofthe boss 47. The boat shape of boss 47 allows the boss 47 to easily enter between the pegs 49 while being scraped by the pegs 49 adjacent the walls 45. Due to the fact that the faces 48 of the boss 47 are relatively small, far apart and inclined with respect to each other, it would 3 be very difficult to secure a U-shaped member against said faces 48.

According to another feature of the inven tion, the latch 34 (figure 6) comprises two further diametrically opposed wings 52 which are bent back (figure 5) so that their path avoids the shells 37. The wings 52 are adapted to cooperate with two respective channel-like retainers 53 which are symmetri cally disposed with respect to axis XX and which are carried by a plate 54 secured to the cover 3 between the latch 34 and the lock 32. The retainers 53 are so disposed as to ensure that both wings 52 engage the retain ers 53 when both wings 36 engage the shells 37.

According to a further feature of the inven tion, the retaining block 44 is adapted so as to receive therein two packing boxes 56 through which the electric wires 57 for con- 85 necting the electric meter to respectively the network and. the user's installation are re ceived. Each packing box 56 is provided with a packing screw 58 attainable from inside the body 1 and not from the outside thereof.

The box just described operates as follows:

While the cover 3 is apart from the body 1, the latter is secured to a support such as the wall 16 by means of the screws 14 and then the lids 21 are secured to the respective walls 95 19 by means of the special screws 22. Then, an electric meter and/or another apparatus is secured to the body 1 by means of the slides9. The wires 57 are inserted into the packing boxes 56 and the screws 58 are tightened from inside the body 1. The wires 57 are also connected to the apparatus or apparatuses. The latch 34 being in the release position, the cover 3 is placed on the body 1 by the employee by inserting the rib 28 (figure 1) in the groove 24 while compressing the spring blade 27. While holding the cover 3 with all of its edges facing the correspond ing edges of body 1, the employee rotates the key 33 until the latch 34 reaches its locked position in which the wings 36 engage the shells 37 while the wings 52 engage the retainers 53. At the same time, bolt 43 irre versibly penetrates the hole 42 so that the box is irreversibly closed. The employee can withdraw key 33 from lock 32 and bring back said key constituting evidence of the correct closure of box 1.

Anyone trying thereafter to fraudulently open box 1 cannot use the key 33 or a master key. If he tries to pull the cover 3 to separate it from the body 1, the pulling force will be transmitted from cover 3 to the housing of the lock 32 to the plate 54, the retainers 53, the latch 34, the shells 37, the retainer block 44 and the body 1. In other words, due to the provision of retainers for the latch 34 both on the cover 3 and on the body 1, the pulling action is not transmitted by delicate parts of the lock 32. Moreover, if the pulling action is GB 2 159 633A 3 very strong such pulling action will break the breakable connections 18 before any damage is done to the locking means 29, 31. The body 1 will then come free from its support wall and the pulling effort will be discontinued for this reason. However, the lids 21 of each fastening means 13 prevent access to the inside of the box even after breakage of the connections 18.

If someone should try to open the box by drilling the lock 32, this will also have low chances of success because it would be very difficult to remove the latch 34 from its retain ers 37 and 52. As a matter of fact, even if the defrauder succeeds in completely disconnecting the latch 34 from the lock 32, the latch 34 is held in place by the retainers 37 and 53 and by the spring catch means 41 to 43.

The employee cannot withdraw the key 33 without having correctly shut the box. Especially, if he rotates the key 33 to place the latch 34 in the locked position without its engaging the retaining means 37 of the body 1, it will be impossible for him to maintain the cover 3 in an apparently closed position. On the one hand, the latch 34 will prevent the lateral edges and the lower edge of cover 3 from being brought in close contact with the corresponding edges of the body 1, and on the other hand, the spring blade 27 will push the cover 3 downwardly. As a consequence, the cover 3 necessarily falls down and the body 1 remains obviously open.

Should the employee try to prevent spring catching of the latch 34 when engaged with the shells 37 by inserting the U-shaped object 51 of figures 13 and 14, this U-shaped object will be swept away by the pegs 49 before the bolt 43 matches with hole 42. Therefore spring catching will neverthe less take place and reopening of the box will be prevented.

It should also be noted that due to the packing screws 58 being inside the box, it is impossible to get access to the box 1 once closed by disassembling the packing boxes 56.

For all these reasons, it will be apparent that the invention provides a very efficient means for protecting electric meters or the like against fraud.

The invention is not limited to the embodiment as depicted and shown and various modifications may be made thereto. For example, instead of being vertical, the plane of the aperture 2 may be oblique provided that the slope is sufficient to allow the cover 3 to slide down when not locked.

The means for irreversibly maintaining the locking member in the locked position may be for example ratchet means.

Claims

1. A box, especially for an electric meter or similar apparatus needing protection against fraud, theft and the like, comprising two cas- 4 GB2159633A 4 ing portions (1, 3) which are a hollow body (1) provided with an aperture (2) and a cover (3) adapted to close the aperture (2) of the body (1), one of the casing portions (3) carry ing a locking mechanism (29) operable by a key (33) and provided with a locking member (34) movable with respect to said casing por tion (3) between an operative position allow ing engagement of a retaining means (37) of l 0 the other casing portion (1) and a release position, the locking mechanism (31) being adapted so as to allow removal of the key (33) when the locking member (34) is in the locked position and to unremovably retain the key (33) when the locking member (34) is in the release position, and the box comprising means for substantially irreversibly maintain ing the locking member (24) in the locked position when the locking member (34) and the retaining means (37) are mutually en- 85 gaged.

2. A box according to claim 1 wherein said means (41, 42, 43) for maintaining the lock ing member (34) in the locked position are partly carried by said other casing portion (1).

3. A box according to claims 1 or 2, wherein said means for maintaining the lock ing member in the locked position comprises spring catch means (41, 42, 43).

4. A box according to claim 3 wherein the spring catch means comprises mutually cooperating locking elements (41, 43) and wherein at least one (41) of said locking elements (41, 43) is provided with clearing means (49) adapted to clear the other (43) said locking element of foreign objects (51).

5. A box according to claim 4, wherein the spring catch means comprises a spring loaded bolt (43) and an apertured element (41) dis- placeable in front of the bolt (43) when the cover (3) is being secured to the body (1), wherein the bolt (43) is surrounded by a boss (47) and the apertured element (41) carries at least one peg (49) travelling alongside the boss (47) during displacement of the apertured element (41).

6. A box according to claim 5, wherein there are two pegs (49) and the boss (47) has substantially a boat shape elongated in the travelling direction of the pegs (49), the distance between the pegs (49) being substantially equal to the broadest transverse dimension of the boss (47).

7. A box according to one of claims 5 or 6, wherein the apertured element (41) is secured to the locking member (34) of the locking mechanism (29) and the spring loaded bolt (43) is carried by said other casing portion (l).

8. A box according to one of claims 1-7, wherein both casing portions (1, 3) are provided with retaining means (37, 53) adapted to engage the locking member (34) in the locked position thereof.

9. A box according to claim 8, wherein the retaining means (37, 53) and the means (41, 43) for irreversibly maintaining the locking member in the locked position are adapted to position the locking member (34) independently of a lock (32) actuated by the key (33).

10. A box according to claims 8 or 9, wherein the locking member (34) is rotatable about an axis of rotation (XX) and is adapted so as to cooperate with retaining means (53) of the one casing portion (3) in two regions located on each side of the axis of rotation (XX), and with retaining means (37) of the other casing portion (1) in two regions located on each side of the axis of rotation (XX).

11. A box according to one of claims 1 -10 comprising means biasing the cover towards an open position clearing the aper ture.

12. A box according to claim 11, wherein the biasing means are operable by gravity of the cover (3).

13. A box according to claim 12, wherein the aperture (2) extends in a steep plane while the body (1) and a top edge (28) of the cover (3) are engageable so as to be mutually slidable along the slope of said plane.

14. A box according to one of claims 1-13 wherein the body is provided with means (17) allowing it to befastened to a support structure such as a wall or the like (16), and wherein said fastening means (13) are connected to the body (1) proper by a breakable connection (18).

15. A box according to claim 14, wherein the fastening means (17) and the breakable connection (18) are insulated from the interior of the body by a lid (21) which is secured to the body (1) so as to be unremovable from outside the body (1) even after breakageof the breakable connection (18).

16. A box according to claim 15, wherein the lid (21) is secured to the body (1) so as to be unremovable from inside the body (1).

17. A Cox substantially as herein described with reference to the accompanying drawings.

18. Any novel feature or combination of features described herein.

Printed in the United Kingdom for Her Majesty's Stationery Office, Dd 8818935. 1985. 4235. Published at The Patent Office, 25 Southampton Buildings. London, WC2A lAY, from which copies may be obtained.