US3736016A

US3736016A - Lock guard for trailer doors

Info

Publication number: US3736016A
Application number: US00205206A
Authority: US
Inventors: C G Garvey; H Mccoy
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-12-06
Filing date: 1971-12-06
Publication date: 1973-05-29
Anticipated expiration: 1990-05-29

Abstract

The lock guard includes an enclosure secured to one of pivoted double doors on a trailer. The enclosure projects beyond the edge of the one door and encloses a pair of hasps when the doors lie in a closed position. An access opening is provided through the bottom wall of the enclosure to facilitate locking and unlocking a padlock joining the hasps. A second opening is provided through the upper wall of the enclosure in registry with the bottom access opening. The standard locking cam rod for trailer doors extends through these openings.

Description

United States Patent 91 Garvey et al.

[541 LOCK GUARD FOR TRAILER DOORS [761' Inventors: C. Godfrey Garvey, 2918 Center Drive, Ellicott City, Md. 21043; Harry Paul McCoy, R.R. No. 1, Box 340 A, Owings Mills, Md. 21117 221 Filed: Dec. 6; 1911 211 Appl. No.: 205,206

[451 May 29,1973

FOREIGN PATENTS OR APPLICATIONS 64,533 6/1946 Denmark ..292/281 678,228 8/1952 Great Britain..... ...70/DIG. 56 103,308 2/1964 Norway ..70/56 Primary Examiner-Albert G. Craig, Jr. AttorneyRobert E. LeBlanc, Henry Shur, Leonard F. Stoll'et al.

57 ABSTRACT The lock guard includes an enclosure secured to one of pivoted double doors on a trailer. The enclosure projects beyond the edge of the one door and encloses a pair of hasps when the doors lie in a closed position. An access opening is provided through the bottom wall of the enclosure to facilitate locking and unlocking a padlock joining the hasps. A second opening is provided through the upper wall of the enclosure in registry with the bottom access opening. The standard locking cam rod for trailer doors extends through these openings.

8 Claims, 6 Drawing Figures Patented May 29, 1973 2 Sheets-Sheet 1 Patented May 29, 1973 2 Sheets-Sheet 2 LOCK GUARD FOR TRAILER DOORS The present invention relates to a lock guard for preventing unauthorized removal of a lock and particularly relates to a lock guard for use on trailer doors for preventing unauthorized removal of equipment and the like contained in the trailer van.

In many instances, locks, for example of the padlock type having a shackle extending through a pair of hasps, are utilized to secure doors and the like in a closed position and thereby prevent access to the associated containers. Such locks, however, do not effectively serve their intendedpurpose as they are readily broken. For example, a bar may be readily inserted within the shackle of an ordinary padlock and utilized as a lever to break or pry the shackle from the lock.

Thus, the very purpose of the lock is defeated and access is easily obtained to the locked container or the like.

This problem of unauthorized entry has become particularly acute at construction sites where construction trailers are locked and left unattended for extended periods of time. Theft of construction and other equipment contained within the trailers by breaking the locks and opening the trailers has reached substantial proportions. The usual trailer lock, provided in conjunction with one or more cam rods having pins at opposite ends engageable in keepers attached 'to the trailer frame at its upper and lower sides, has not proved effective to prevent unauthorized entry into the trailer.

A number of different types of guards for locks have been proposed and constructed in the past. Particularly, US. Pat. No. 3,590,607 discloses a guarded lock assembly comprised of a generally rectangular housing mounted on a swinginghasp. The housing is open at one end and a padlock is received within this opening. The opening provides access to the lock. An additional guard for the lock emcompasses the shackle inside the outer enclosure. In U.S. Pat. No. 3,392,555, there is provided a padlock having a guard assembly and which padlock and guard assembly are received within an enclosure. However, this enclosure is open along at least one side thereof and would not be effective topreclude unauthorized tampering with the shackle of the lock.

The present invention provides a guard for locks which eliminates and/or minimizes the foregoing described and other problems associated with prior lock guards and provides a novel and improved lock guard particularly useful with trailer doors and the like and having various advantages in construction and use as compared with such prior lock guards. Particularly, the present invention provides an enclosure having top, bottom, front and end walls secured along an edge of a trailer door and enclosing a hasp secured to the trailer door. The enclosure projects laterally beyond the edge of the trailer door. When the door lies in a closed position, the projecting portion overlies a hasp on a fixed portion of the trailer or on another door. An opening is provided through the bottom wall of the enclosure. This opening provides for access into the enclosure for the purpose of locking and unlocking a lock, the shackle of which is received through aligned openings in the hasps. While bars or other tools and the like which could be utilized aslevers to breakthe padlock maybe received through the access opening, this opening is small and close to the padlock whereby leverage of the magnitude sufficient to break the lock cannot be obtained. A second opening is provided through the top wall of the enclosure in vertical registry with the bottom access opening. These aligned openings receive the cam rod of a standard trailer door whereby the enclosure does not interfere with the cam rod.

In another form hereof, the lock guard is applied to a roller type door. In the closed position, the guard encloses a lock applied to hasps secured to the door and vehicle frame respectively. Access to the lock within the enclosure is limited whereby bars, levers or the like cannot be inserted with leverage sufficient to force the lock.

Accordingly, it is a primary object of the present invention to provide a novel and improved guard for a trailer door lock.

It is another object of the present invention to provide a novel and improved lock guard for trailer doors and the like which is readily and easily secured to existing trailer doors.

It is still another object of the present invention to provide a novel and improved lock guard for trailer doors and the like wherein access to the lock is limited.

It is a related object of the present invention to provide a novel and improved lock guard for substantially entirely enclosing a lock on a vehicle door wherein access to the lock issufficiently limited as to prevent forcing the lock by levers or the like.

It is a further object of the present invention to provide a novel and improved lock guard for the locks on trailer doors and the like wherein the guard per se is simple in construction, readily, easily and inexpensively fabricated.

These andfurther objects and advantages of the present invention will become more apparent upon reference to the following specification, claims and appended drawings, wherein:

FIG. 1 is a perspective view of a trailer illustrating a lock guard constructed in accordance with the present invention and applied to the double doors of a trailer;

FIG. 2 is an enlarged fragmentary perspective view of the lock guard with parts broken out and in cross sectron;

FIG. 3 is a cross-sectional view thereof taken generally about on line 3-3 in FIG. 2;

FIG. 4 is an enlarged cross-sectional view thereof taken generally about on line 4-4 in FIG. 2;

FIG. 5 is a fragmentary enlarged cross-sectional view of the carriage bolt securing the lock guard to the trailer door and taken generally about on line 55 in FIG. 4; and

FIG. 6 is a rear end elevational view of the lock guard of the present invention as applied to a roller type door.

Referring now to the drawings, particularly to FIG. 1, there is disclosed a conventional trailer, generally indicated 10, comprised of a van 12 mounted ona set of rear wheels 14 and a pair of supports 16 adjacent the front of the van. It will be appreciated that the trailer is releasably attached to a cab, not shown, whereby the trailer is transportable as part of a road vehicle. The trailer 10 may be utilized, for example at a construction site, for the storage of construction tools and the like. The trailer includes double doors l8 and 20 hinged to the opposite sides of van 12 at 22 and 24 respectively. Door 20 overlaps door 18 at their juncture and is provided with conventional locking cams 28 which cooperate with keepers mounted on the trailer frame for maintaining the

doors

18 and 20 in a locked closed position. The cams 28 are operated by a handle 30 secured to a vertically extending cam rod 32, the opposite ends of which carry the cams 28. It will be appreciated that handle 30 may be locked, for example by a padlock, to preclude rotation of the cam rod. However, as will be appreciated, this handle lock can be readily broken by a bar or lever whereby unauthorized access to the trailer can be easily obtained. The foregoing described trailer is, of course, conventional in construction and forms no part of the present invention.

In accordance with the present invention, there is provided an additional lock and a lock guard therefor which cooperate one with the other to prevent unauthorized entry into van l2. Particularly, the doors l8 and are provided with

hasps

34 and 36 respectively which, when the doors are closed, receive the shackle 38 of an additional padlock, generally indicated 40. Padlock 40 may be of any conventional type of padlock having a key opening along the underside of its locking body 41.

While the padlock conventionally used to lock handle 30 may be readily broken due to its external accessibility, according to the present invention, there is provided a lock guard, generally indicated 42, for padlock 40. Particularly, lock guard 42 limits access to lock 40 by bars, levers or the like to the extent that leverage sufficient to force lock 40 by application of such tools cannot be obtained. Lock guard 42, however, permits ready access to the key opening of lock 40 whereby the lock 40 can be readily removed by authorized individuals. Guard 42 comprises an enclosure 44 having top and

bottom walls

46 and 48 respectively, end walls 50, and a front wall 52. Enclosure 44 is open along the side thereof opposite front wall 52. For purposes which will become clear from the ensuing description, the top wall 46 is provided with an opening 54. Bottom wall 48 is also provided with an opening 56 in vertical alignment with the opening 54 for reasons set forth hereinafter.

Enclosure 42 is preferably secured to the door which overlaps the other door, in this instance, the door 20. To effect the securement,

angle brackets

58 and 60 are secured, for example by welding or the like, to the top wall 46 and an end wall 50, respectively. The brackets are secured such that, when the rear edges of enclosure 44 are located against door 20, the

flanges

62 and 64 of

brackets

58 and 60 respectively lie flush with the edges of the enclosure and against door 20. Suitable openings are provided in

flanges

62 and 64 to receive carriage bolts 66 of the type having a square shank portion. The bolts 66 are secured on the inside face of door 20 by lock washers 67 and nuts 69. It will be appreciated from the foregoing described construction that enclosure 44 swings with door 20. When door 20 is closed and overlaps the edge of door 18, an end portion of enclosure 44 also overlies door 18.

As best illustrated in FIG. 2, opening 54 in enclosure 44 provides a rearwardly opening slot for receiving c'am rod 32. Opening 56 permits access to the lock 40 within enclosure 44. This access opening is sufficiently small as to preclude forcing lock 40 by insertion of bars, levers or like tools. Since opening 56 is small and close to lock 40, leverage of the magnitude sufficient to break the lock cannot be obtained. Opening 56, on the other hand, is sufficiently large such that access to lock 40 within the enclosure for the purposes of locking and unlocking the double doors is readily obtained. The opening 56 is also located in vertical registry with padlock 40 as well as opening 54 whereby cam rod 32 extends through both

openings

54 and 56. That is, enclosure 42 does not interfere with the normal operation of the cam rod 32.

To utilize the lock guard and additional lock of the present invention, the

hasps

34 and 36 are first secured, by carriage bolts 37, to the

double doors

18 and 20 an equal distance from the double door centerline so that the hasps just miss one another when door 20 swings between open or closed positions. The hasps lie in lateral registry one with the other when the doors lie in a closed position. The door 20 is provided with openings to receive the carriage bolts 66. The enclosure is then secured to door 20 by bolts 66 with the

openings

54 and 56 receiving the cam rod 32. It will be appreciated that the right hand door is the primary opening door and that the enclosure is therefore secured to this door. Should the left hand door constitute the primary door, the enclosure would be secured to the left hand door in like manner.

After the enclosure is secured to the door 20, it will be appreciated that the enclosure overlies both doors when the latter lie in a closed position with the portion of the enclosure projecting laterally from door 20 overlying and engaging against door 18 thereby preventing access to within the enclosure. The shackle 38 of padlock 40 is then inserted through the openings in the hasps and secured in lock body portion 41. This is readily accomplished since the opening 56 is sufficiently large as to permit manipulation of the padlock for the purposes of closing the shackle. After the padlock is secured, it is readily apparent that crowbars or like tools cannot be utilized on opening 54 for the purpose of forcing the lock. Particularly, leverage to break lock 40 or its shackle by insertion of such tools through opening 56 simply cannot be obtained due to the limited access to the lock 40 through opening 56. Thus, unauthorized entry to the trailer is precluded, notwithstanding the breaking or removal of the conventional lock utilized with handle 30.

In a specific preferred embodiment of the present invention, the enclosure is 12 inches from end to end, 6 inches in depth, that is, from the front wall 52 to the face of the doors, and has a height of about 6 inches. The enclosure is formed of one-quarter inch or 3/16 inch plate steel with all seams welded one to the other. The opening 54 is about 1 inches wide and about I 7% inches deep. Opening 54 is offset about 1 inch from the center of the enclosure and hence about 1 inch to one side of the centerline of the double doors. The access opening 56 is preferably 4 inches wide and 3 inches deep. The enclosure and hasps are relatively located such that the key opening for padlock 40 is about one-half inch above the bottom wall of the enclosure. It will be appreciated that for those doors not having the cam rod and associated locking devices, the opening 54 through the top wall of the enclosure can be omitted.

In the embodiment hereof illustrated in FIG. 6, a lock guard, generally indicated 70, constructed in accordance with the present invention is applied to a roller typetrailer door. Particularly, the trailer includes a van 72 having an overhead articulated door 74 mounted on rollers positioned in guides along the side frame, the rollers and guides not being shown. It will be appreciatedthat adoor of this construction is conventional and thatthe'do'or is illustrated in the closed position.

The lock guard 70 comprises an enclosure similar to the enclosure previously described. Like numerals with the suffix a indicating the lock guard of this embodiment thus designate like parts. Particularly, lock guard 70 is secured to either the lower frame 76 of door 74 or to the truck body 78 by means of the angle brackets 62a and 64a and bolts 66a. Also secured to the frame 76 is a hasp 36a. A similar hasp 34a is secured to the lower frame 78 of the van. The enclosure is provided with side walls 80 and upper and lower end walls 82. The lower end wall is provided with an opening 84 for receiving' the fixed hasp 34a mounted on frame 78 when the door is moved between open and closed positions. The opening 84 is small and has dimensions sufficient only to provide sufficient clearance for the hasp. In one of the side walls 80, there is provided an access opening 86. It will be appreciated that, when the door is closed, the enclosure carried thereby encloses both hasps 34a and 36a with the former being received through the openings 84. The shackle of the padlock is then inserted through the openings in the hasps from the side access opening 80 which again has similar dimensions as the access'opening 56 of the previous embodiment. lt will be appreciated that the enclosure fully encompasses the hasps and lies flush against the

frame

76 and 78 when the door is closed. As in the previous embodiment, access to the padlock cannot be obtained to the degree necessary to obtain sufficient leverage with a lever or the like to force the padlock.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

-1. A lock guard for use on a vehicle having a swinging door with a generally vertically extending rod cooperable with keepers to retain the door in a closed position, the door including a lock cooperable with a pair of locking members to lock the door in the closed position comprising: an enclosure having top, bottom, front and end walls, means for securing said enclosure to the door in position substantially overlying the locking members and lock, said enclosure having an opening through one of said'walls providing for access to the lock within the enclosure and a second opening through another of said walls for receiving the retaining rod, said openings being sized to limit access within said enclosure such that the lock cannot be forced by insertion of levers or the like through said opening.

2. A lock guard according to claim 1 wherein said first and second openings are located in the respective vertically spaced walls of said enclosure in vertical registry one with the other whereby the rod is receivable through both of said openings.

3. A lock guard according to claim 1 wherein said securing means includes a pair of angle brackets welded to said enclosure.

4. A lock guard according to claim 2 wherein said second opening is smaller than said first opening.

5. A look guard according to claim 1 in combination with said vehicle, said vehicle mounting said swinging door and said rod, said locking members comprising a pair of hasps respectively secured to said swinging door and said vehicle, said enclosure encompassing said hasps when said door lies in a closed position.

6. A lock guard according to claim 5 wherein said vehicle has a second swinging door cooperable with said first mentioned door, the other of said hasps being carried by said second door, said enclosure being carried by said first door and projecting beyond its edge to overlie said second door, the projecting portion of said enclosure being open on its rear side to receive said other hasp when said doors are swung to a closed position.

7. A lock guard according to claim 1 wherein said access opening is no greater than 12 square inches with a dimension thereof from one side of the opening to the other being at least 3 inches.

8. A lock guard for use on a vehicle having a door and a lock cooperable with a pair of locking members carried by the vehicle frame and the door respectively for locking the door to the frame in the closed position comprising: an enclosure having top, bottom, front and end walls, means for securing said enclosure to one of the door and vehicle frame in position substantially overlying the locking members and lock, said enclosure having an opening through one of said walls providing for access to the lock within the enclosure and a second opening through another of said walls for receiving one of the locking members, said openings being sized to limit access within said enclosure such that the lock cannot be forced by insertion of levers or the like through said opening.

Claims

1. A lock guard for use on a vehicle having a swinging door with a generally vertically extending rod cooperable with keepers to retain the door in a closed position, the door including a lock cooperable with a pair of locking members to lock the door in the closed position comprising: an enclosure having top, bottom, front and end walls, means for securing said enclosure to the door in position substantially overlying the locking members and lock, said enclosure having an opening through one of said walls providing for access to the lock within the enclosure and a second opening through another of said walls for receiving the retaining rod, said openings being sized to limit access within said enclosure such that the lock cannot be forced by insertion of levers or the like through said opening.

5. A lock guard according to claim 1 in combination with said vehicle, said vehicle mounting said swinging door and said rod, said locking members comprising a pair of hasps respectively secured to said swinging door and said vehicle, said enclosure encompassing said hasps when said door lies in a closed position.