Closure Device For Locks

Abstract

An integrally formed closure unit including an annular base, a cap and a flexible connector as member portions. An annular seal surface on the base is dimensionally mated to a mating surface on the cap so as to be slidably engagable therewith. After mounting of the annular base around an opening to be protected, the cap can be manipulated into either open or closed positions.

Description

BACKGROUND OF THE INVENTION

This invention relates generally to a cover device which when mounted over an opening can be manipulated into positions that either protect the opening or allow physical access thereto. A preferred embodiment of the invention functions as a keyhole cover for locks.

Various problems are caused by the entry of dirt, mosture and other foreign matter into the keyholes of locks. The penetration of such materials into a lock chamber results in wear, rust and other forms of deterioration that can ultimately cause failure and necessitate removal and replacement of the damaged lock. In all cases expensive and time consuming, the replacement of a lock that has become inoperative in the locked condition is particularly troublesome in that a forced entry generally must be made into a locked compartment. Other problems are caused by freeze-up of moisture that has entered a lock through its keyhole. In attempts to alleviate these problems, various types of lock covers have been developed. Such covers typically are multi-element devices including a cap member for covering the keyhole, a biasing spring member therefor and some mechanism for attachment to a lock case. In addition, prior lock covers have been designed either as an integral part of a lock or for use with one particular lock. All of these factors substantially increase the cost of a given lock and therefore have limited the use of covered locks.

The object of this invention, therefore, is to provide an improved, less expensive lock, particularly of the panel mounted cylinder type, that can be protected from deterioration caused by the inadvertent entry of foreign materials.

SUMMARY OF THE INVENTION

The present invention consists of a lock cover device integrally formed of a resilient plastic material and including a base member, a cap member and a connector therebetween. The annular base member is adapted for mounting around an opening to be protected and includes an annular shell with a wall portion that encloses that opening and forms a sealing surface. Formed on the cap member is a mating surface dimensionally mated to the seal surface and movable into sliding engagement therewith so as to create a seal around the protected opening. Because of its unitary construction, the cover can be produced at minimal cost by conventional plastic molding equipment. Furthermore, a given cover can provide tight seals for open structures of varied size since both surfaces used to create a closure seal are included in the cover unit itself.

A preferred combination embodiment of the invention utilizes a cover of the type described above with a conventional cylinder lock. The cover base portion has an aperture shaped to accommodate the typical, partially flatened cylindrical case of the lock. During assembly, the cover base is positioned between a panel and the head portion of the lock which extends through an opening in the panel and is secured thereto in a conventional manner. The base functions both as a gasket for the lock and as a seal surface that can be engaged by the mating surface of the cap member to provide a tight closure over the lock's keyhole.

In one featured embodiment of the invention, the seal surface of the base member is formed by the inner surface of a rectangular shell and the cap member includes a rectangular outer surface dimensionally mated to the seal surface so as to be slidably engagable therewith. A modified embodiment employs the outer surface of a cylindrical projection on the base member and the inner surface of a cylindrical projection on the cap member as seal and mating surfaces. A feature of the latter embodiment are resilient jaws formed by recesses in the cylindrical extension of the cap member. The jaws automatically latch over a flexible connector joining the base and cap members during engagement between their seal and mating surfaces so as to prevent inadvertent opening of the closure formed thereby.

DESCRIPTION OF THE DRAWINGS

These and other objects and features of the invention will become more apparent upon a perusal of the following description taken in conjunction with the accompanying drawings wherein:

FIG. 1 is a plan view of a preferred closure embodiment of the invention;

FIG. 2 is a cross-sectional view taken along lines 2--2 of FIG. 1;

FIG. 3 is a cross-sectional view taken along lines 3--3 of FIG. 1;

FIG. 4 is a bottom view of a lock assembly incorporating the closure shown in FIGS. 1-3;

FIG. 5 is a cross-sectional view taken along lines 5--5 of FIG. 4;

FIG. 6 is a plan view of a modified closure embodiment of the invention; and

FIG. 7 is a cross-sectional view taken along lines 7--7 of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1-3 there is shown a cover unit 11 including a base member 12 attached to a cap member 13 by a connecting band 14. The base member 12, cap member 13 and connector 14 are intregally formed as a single unit from a suitable resilient, plastic material. Composing the base member 12 is a right cylindrical shell 15 extending perpendicularly from the periphery of a circular bottom portion 16. The bottom 16 is made annular by a centrally located aperture 17 bounded by a pair of straight edges 18 separated by curved edges 19.

The cap member 13 similarly includes a tubular portion 21 in the form of a hollow right cylinder extending perpendicularly from the periphery of a circular top 22. As shown more clearly in FIG. 3, the tubular portion 21 possesses a pair of triangularly shaped recesses 23 separated by a central recess 24. A re-entrant portion 25 in the recess 24 is joined by a slot 26 that extends to the connector band 14. Together the recesses 23 and 24 form a pair of resilient latching jaws 27 and 28 the function of which is described in detail below.

FIGS. 4 and 5 illustrate a preferred covered lock embodiment 31 employing the closure 11 shown in FIGS. 1-3. In addition to the cover 11, the lock assembly 31 includes a conventional cylindrical lock having a case portion 32 and a head portion 33. The externally threaded cylindrical case 32 possesses the familiar flattened portions 34, one of which is shown in FIG. 5, that create a cross section having the shape of the aperture 17 shown in FIG. 1. To assemble the lock assembly 31, the base member 12 is first positioned so as to align its aperture 17 with a similarly shaped opening 35 in a mounting panel 36. Next, with the cap member 13 in the open position, shown dotted in FIG. 5, the case 32 is inserted through the aperture 17 and opening 35 until the head portion 33 engages the base bottom portion 16. A nut 37 is then screwed onto the threaded case 32 until engagement with the inner surface of the panel 36 secures the assembly in place.

With the cap member 13 in open position a key can be freely inserted into the head portion 33 to operate the lock in the normal manner. However, during periods of non-use, the interior of the lock can be fully protected from foreign materials such as dirt, moisture, etc., by merely moving the cap 13 into the closed position shown in FIGS. 4 and 5. This is accomplished simply by pushing the cap 13 onto the base 12 during which an outer seal surface 38 of the base cylinder 15 slidably engages the identically dimensioned inner mating surface 39 of the cap cylinder 21. The closure action is simplified by a centrally located recess 41 in the connecting band 14 that provides it with greater flexibility.

Once closed, inadvertent opening of the cover unit 11 is prevented by the latching action of the jaw members 27 and 28 shown in FIG. 3. During movement of the cap 13 onto the base 12, the jaws 27 and 28 engage the flexible connector band 14 and are slightly separated thereby. However, in fully closed position with the top 22 of the cap 13 engaging the upper edge of the base cylinder 15 (FIG. 5), the ears 27' and 28' extend past the band 16 allowing the jaws 27 and 28 to close as shown in FIG. 4. In that position, the ears 27' and 28' project behind the connecting band 14 and thereby restrain removal of the cap member 13.

The restraining force provided by the jaws 27 and 28 can be manually overcome to permit opening of the cap member 13 when access to the lock is desired. A specific advantage of the cover unit 11 is that the closure seal formed between the surfaces 38 and 39 is independent of the lock itself. For this reason, a given cover unit 11 can be used with a lock of any size provided that its head portion can be accommodated within the volume enclosed by the base cylinder 15.

FIGS. 6 and 7 illustrate another cover embodiment 51 including a base member 52 joined to a cap member 53 by a connector band 54. Again, the base 52, the cap 53 and the connector 54 are an integral unit formed of a suitable plastic material. The base member 52 includes a rectangular hollow shell 55 extending perpendicularly from the periphery of a flat bottom portion 56. A rectangular aperture 57 in the bottom portion 56 provides the base member 52 with an annular shape. The inner wall 58 of the rectangular shell 55 forms a seal surface dimensionally mated to a mating surface 59 formed by the edge of the cap block 53. Thus, a tight seal is created by the sliding engagement between the seal surface 58 and the mating surface 59 when the cap 53 is pressed into the base member 52 as shown by solid lines in FIG. 7. However, in this embodiment 51 a separate latching mechanism is not provided and the cap member 53 is maintained in closed position only by the frictional forces exerted between the seal surface 58 and the mating surface 59.

The cover unit 51 is used in a manner analogous to that described above in connection with the cover unit 11. After mounting the base member 52 on a structure (not shown) possessing an opening to be protected and aligning the aperture 57 therewith, the opening is sealed by merely pressing the cap block 53 into the base member 52 as shown in FIG. 7. Conversely, access to the opening is obtained by simply moving the cap member 53 into the open position shown by dotted lines in FIG. 7. Although the unit 51 can be secured around an opening to be protected by a structural arrangement of the type shown in FIGS. 4 and 5, other mounting techniques also can be employed. For example, the base member 52 can be secured to a surface (not shown) surrounding an opening by screws, nails, cement etc.

One preferred use of the embodiment 51 is as a closure for conventional electrical outlet receptacles. For mounting in that application the base member 52 is first positioned with the aperture 57 aligned around the receptacle's socket openings and after removal of a typical face plate (not shown). The face plate is then inserted into the cavity formed by the shell 55 and tightened in the customary manner against the flat bottom 56 to thereby fix the unit 51 in place. Appropriate manipulation of the cap 53 between open and closed positions, respectively, either provides access to the exposed plug receptacles or seals them from foreign elements.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is to be understood, therefore, that the invention can be practiced otherwise than as specifically described.

Claims

What is claimed is:

1. A cover device comprising:

a. an annular base member adapted for mounting around an opening to be closed, said base member comprising an annular seal surface for enclosing the opening to be closed;

b. a cap member for covering the opening, said cap member comprising a mating surface adapted to engage said seal surface;

c. a connector means connecting said base member to said cover member and permitting relative movement therebetween; and wherein said base member, said cover means and said connector are integrally formed of a flexible plastic material; and

d. latching means also integrally formed with said base member, said cap member and said connector means; said latching means being automatically activated in response to engagement between said seal and mating surfaces to restrict relative movement between said cap member and said base member, and wherein said connector means is a flexible band joining said cap and base members, and wherein said cap member comprises said latching means which is disposed for releasably engaging said band to restrict relative movement between said cap and base members in response to movement of said mating surface into contact with said seal surface.

2. A cover device according to claim 1 wherein said base member comprises an annular shell with a wall portion that forms said seal surface; and said mating surface is mated dimensionally to said seal surface so as to be slidably engagable therewith.

3. A cover device according to claim 2 wherein said annular seal surface comprises an outer surface of said annular shell, and said cap member comprises a hollow tubular portion the inner surface of which comprises said mating surface.

4. A cover device according to claim 3 wherein said annular shell is a hollow cylinder.

5. A cover device according to claim 4 wherein said annular seal surface is a right cylindrical wall surface of said hollow cylinder.

6. A cover device according to claim 2 wherein said annular seal surface comprises an inner surface of said annular shell, and said cap member comprises a projection with an outer surface that comprises said mating surface.

7. A cover device according to claim 6 wherein said annular shell is of rectangular cross-section.

8. A cover device according to claim 1 wherein said base member comprises an annular shell with a wall portion that forms said seal surface; and said mating surface is mated dimensionally to said seal surface so as to be slidably engagable therewith.

9. A cover device according to claim 8 wherein said annular seal surface comprises an outer surface of said annular shell, and said cap member comprises a hollow tubular portion the inner surface of which comprises said mating surface.

10. A cover device according to claim 9 wherein said latching means comprises resilient jaws that define recesses in said hollow tubular portion.

11. A cover device according to claim 1 wherein said annular base member defines an aperture bounded by a pair of straight edges separated by a pair of curved edges.

12. A lock apparatus with an interior protected from external elements comprising in combination:

a. a lock comprising a keyhole defining head portion, a case portion extending longitudinally from said head portion, said case portion being of reduced transverse cross-section so as to permit its insertion through a panel opening that restricts movement of said head portion;

b. an annular base member adapted for mounting around the opening and between the panel and said head portion, said base member comprising an annular seal surface for enclosing said keyhole;

c. a cap member for covering the head portion, said cap member comprising a mating surface adapted to engage said seal surface;

d. a connector means connecting said base member to said cover member and permitting relative movement therebetween; and wherein said base member, said cover member and said connector means are integrally formed of a flexible plastic material; and

e. latching means also integrally formed with said base member, said cap member and said connector means; said latching means being automatically activated in response to engagement between said seal and mating surfaces to restrict relative movement between said cap member and said base member, and wherein said connector means is a flexible band joining said cap and base members, and wherein said cap member comprises said latching means which is disposed for releasably engaging said band to restrict relative movement between said cap and base members in response to movement of said mating surface into contact with said seal surface.

13. A lock apparatus according to claim 12 wherein said base member comprises an annular shell with a wall portion that forms said seal surface; and said mating surface is mated dimensionally to said seal surface so as to be slidably engagable therewith.

14. A lock apparatus according to claim 13 wherein said annular seal surface comprises an outer surface of said annular shell, and said cap member comprises a hollow tubular portion the inner surface of which comprises said mating surface.

15. A lock apparatus according to claim 14 wherein said annular shell is a hollow cylinder.