Latch and lock structure

Abstract

Latch and lock structure for a door wherein the latch includes a bolt and is pivotally mounted upon the door for movement around an axis substantially perpendicular to the plane of the door when it is in its closed position. The latch has an end portion with a recess opening radially of said axis. A bracket is secured to the door for engagement by the latch when it is in the latch position. An L-shaped lever is pivotally secured to the bracket and has an abutment on one leg thereof which is receivable into said recess when said latch is in the latched position. Actuating means engages the other leg of said L-shaped lever for pivoting same and thereby moving said abutment out of said recess. Resilient means yieldably urges said abutment means into the locked position, said actuating means limiting the amount of said urging.

Description

BACKGROUND OF THE INVENTION

This invention relates in general to a latch and lock structure for a door and, more particularly, to a type thereof adapted for mounting upon an upwardly acting truck door, the latch means being capable of automatic self-adjustment to compensate for looseness, and a lock means including a tamper-proof device for locking the latch in the locked position whereby to provide maximum security within the truck.

Persons familiar with the manufacture, installation and maintenance of doors, particularly upwardly acting doors for truck vans, for example, have long been aware that the latch structures in such doors are subject to unusually rough treatment, even under substantially normal operating conditions. That is, truck doors and their latch structures are constantly exposed to the weather, they are often strained by the loads carried in the truck van or battered by external obstructions, and they are frequently subjected to excessive and distructive forces, sometimes intentionally for the purpose of effecting unauthorized access to the contents of the truck van.

Where looseness exists between the latch bolt on a door and the catch on the truck bed, the result is a noisy and unsightly door the movements of which tend to aggravate the wear problem and usually accelerate latch and/or lock failure. U.S. Pat. No. 3 642 314, which is assigned to the Assignee of this application, discloses and claims a lock structure which minimizes, if not virtually eliminates, most of the above discussed problems which develop from a loose latch and catch condition.

In order to prevent unauthorized entrance into the van of the truck, the door latch structure is usually furnished with some type of mechanism, such as a padlock, which releasably holds the latch handle in the latched position. However, this arrangement has not been altogether satisfactory, if only because it is necessary to furnish expensive padlocks which are frequently misappropriated. The latch and lock structure claimed and disclosed in U.S. Pat. No. 3,740,978 was developed in an effort to provide a tamper-proof lock for the latch structure. This patent is assigned to the Assignee of this application. The lock assembly shown in U.S. Pat. No. 3,740,978 was a step forward and overcame the combined problems of unauthorized entry and stolen padlocks. However, it lacks one highly desirable feature, namely, the ability to return automatically to the locked engagement with the latch handle when the latch handle is returned to its latched position. That is, the locking action is not automatic in the previous lock structure.

Accordingly, a primary object of this invention has been the provision of an improved latch and lock structure for a door, such as an upwardly acting truck door, wherein the latch mechanism is adapted to adjust automatically and thereby minimize looseness between the door and the truck bed resulting from normal wear, minor inaccuracies of installation and/or acceptable tolerances in parts, whereby the useful life of the latch and lock structure and/or the door is extended.

A further object of this invention is the provision of a latch and lock structure for a door in which the latch mechanism includes an elongated handle pivotally mounted upon the door and a spring urged catch lever which is pivotally mounted upon the door, said catch lever being engageable with the latch handle for holding same in the latched position.

A further object of this invention is the provision of a lock mechanism, as aforesaid which positively prevents pilferage of the lock mechanism, which minimizes the possibility of unauthorized opening of the lock, as by force, and which provides for an automatic locking of the latch handle when it is returned to the latched position.

Other objects and purposes of the invention will become apparent to persons familiar with latch and lock structures, particularly for upwardly acting truck doors, upon reading the following descriptive material and examining the accompanying drawings, in which:

FIG. 1 is a broken, fragmentary rear elevational view of a truck door and an adjacent portion of a truck bed including the latch and lock structure embodying the invention.

FIG. 2 is a broken, fragmentary rear elevational view of a truck door and an adjacent portion of a truck bed similar to that shown in FIG. 1 but with parts thereof in different operating positions.

FIG. 3 is an enlarged sectional view taken along the line III--III in FIG. 2.

FIG. 4 is a sectional view taken along the line IV--IV in FIG. 3.

FIG. 5 is a sectional view similar to that shown in FIG. 4 with parts thereof in different operating positions.

FIG. 6 is an enlarged view taken along the line VI--VI in FIG. 2.

FIG. 7 is a sectional view taken along the line VII--VII in FIG. 6.

FIG. 8 is a sectional view taken along the line VIII--VIII in FIG. 4.

For convenience in description, the terms "upper", "lower", "front", "rear" and words of similar import will have reference to the latch and lock structure of the invention and parts of the truck door associated therewith as appearing in FIG. 1 which discloses the rear side of the door. The terms "inner", "outer" and derivatives thereof will have reference to the geometric center of the latch and lock structure of the invention and parts thereof or associated therewith.

SUMMARY OF THE INVENTION

The objects and purposes of the invention, including those set forth above, have been met by providing a latch and lock structure comprising catch means mounted in the bed of a truck or similar vehicle and a latch mechanism mounted upon the lower end of an upwardly acting door of the truck van and having a latch bolt including an elongated hook portion engageable with the catch means. The latch bolt is pivotally mounted upon the door and is moved into the latched position by an actuating member which is releasably held in its latching position by a tamper-proof lock mechanism. Gravity also opposes release of the latch bolt from its latched position. The actuating member is held away from its latching position by a keeper.

DETAILED DESCRIPTION

The latch and lock structure of the invention, a preferred embodiment of which is disclosed in FIG. 1, is comprised of a latch assembly 11 mounted upon the lower end of an upwardly acting door 12 for engagement with a catch assembly 13 that is mounted in the bed 14 of an otherwise substantially conventional truck van, of which the door 12 is a part. The door 12 may be comprised of a plurality of horizontally hinged sections which are disposed in a substantially vertical plane, when the door is closed, and in a substantially horizontal plane near the roof of the van when the door is open. A resiliently flexible weather seal 15 (FIG. 1) is mounted on the lower edge of the door 12 and is engageable with the bed 14 in a conventional manner and for conventional purposes.

The catch assembly 13 (FIGS. 1 and 2) is comprised of an elongated, substantially rectangular casing 17 having a top flange 18, a pair of sidewalls 19 and 20 (FIG. 1) and a pair of end walls 21 and 22 (FIG. 6). The sidewalls 19, 20 and the end walls 21, 22 define a catch chamber 23 which preferably opens upwardly to receive the latch bolt 47 and downwardly for drainage.

The top flange 18 (FIG. 1) preferably extends beyond both end walls 21, 22 and the rear sidewall 20 for engagement with the upper surface 26 of the bed 14 when the casing 17 is located within the opening 27 in the bed 14. The top flange 18 may be secured to the bed 14 by welding, by screws or any other convenient, conventional means. The catch assembly 13 includes a catch pin 29, which is secured to and extends between the sidewalls 19 and 20 of the casing 17 about midway between the end walls 21 and 22.

The latch assembly 11 (FIG. 1) has a mounting plate 31 which is secured to the rear surface of the door 12 adjacent the lower edge thereof by means of rivets 32. The front end of the axle 30 is rigidly secured to the mounting plate 31 by means such as welding and/or staking.

A manually operated actuating member 33 (FIGS. 1 and 2), which is rotatably supported on axle 30, is comprised of a housing 34, the details of which are disclosed in said U.S. Pat. No. 3,642,314. The actuating member 33 (FIG. 1) has an integral handle 43 which projects from the housing 34 lengthwise thereof and substantially radially of the axle 30.

The latch bolt 47 (FIG. 1) has a shank 48, which is rotatably supported at its upper end upon the axle 30, and an elongated, arcuate hook 49 integral with the outer end of the shank 48 and having a slightly cammed inner surface 51. The portion of surface 51 adjacent shank 48 is nearer to axle 30 than is the portion of surface 51 adjacent the free end of the hook 49. The center of gravity of the latch bolt 47, when it is pivotally supported by axle 30 is near the shank 48. Thus gravity urges latch bolt 47 into its locked position of FIG. 2.

An unlatched keeper 53 (FIGS. 1 and 2) is pivotally mounted upon a pivot pin 54 which is rigidly secured to the mounting plate 31 near the housing 34. The keeper 53 has a hook 56 near one end which is engageable with a flange 57 (FIG. 2) on the housing 34 whereby the actuating member 33 and bolt 47 are held in their unlatched positions, which are approximately 180.degree. from their latched positions of FIG. 2.

The free or rightward end of the handle 43 (FIGS. 1 and 2) has a C-shaped portion 61 which, in this embodiment opens radially outwardly, relative to the axle 30.

The lock assembly 62 (FIGS. 4 through 8), which includes the portion 61 of handle 43, also includes the rectangular casing 63 (FIG. 3) which has a top wall 65, bottom wall 66, rear sidewall 67 and end walls 69 and 70. A pair of flanges 72 and 73 (FIG. 7) which are integral with and preferably perpendicular to the end walls 69 and 70, extend away therefrom for mounting the casing 63 on the door 12 by means such as rivets 74.

The top and bottom walls 65 and 66 (FIG. 8) have openings 76 and 77, respectively. The lower leg 78 and bight 79 of the C-shaped portion 61 can move through opening 76 into the positions thereof shown in FIG. 4 from the positions thereof shown in FIG. 1. When the C-shaped portion 61 is in its FIG. 4 position, lateral extensions of the upper leg 82 (FIG. 7) bear against the upper surface of the top wall 65 to positively limit downward movement of the portion 61.

A pivot axle 85 is rigidly secured, as by brazing or staking, to the rear side wall 67 so that it extends toward the door 12 near the lower edge thereof. A substantially L-shaped catch lever 86 is pivotally supported near the intersection of the arms 87 and 88 thereof for movement around a horizontal axis which, in this embodiment, is preferably parallel with the pivotal axis of the axle 85. The catch arm 87, which has a hook or projection 89 near its upper end, is laterally offset rearwardly from the locking arm 88.

The upper edge of the catch arm and its attached hook 89 have a downwardly and leftwardly sloping upper surface 92 which permits the lower leg 78 of the C-shaped portion 61 to slide therealong as it moves downwardly through the opening 76, thereby causing the arm 87 to pivot rightwardly away from the portion 61. A coil spring 93 has one end thereof anchored upon the casing 63, the other end thereof being hooked around the catch arm 87 whereby said catch arm is continuously urged into its locking position with the C-shaped portion 61, as shown in FIGS. 4 and 6. A substantially conventional lock cylinder 94 is mounted upon the rear sidewall 67 so that it extends axially toward the lower edge of the door 12. This is the reason for the offset of the arm 87 rearwardly form the arm 88. A crank 96 is included in the lock cylinder assembly and has a crank pin 97 which is engageable with the upper edge of the locking arm 88 near its outer end, as shown in FIGS. 4, 6 and 7, for rotating the catch lever 86 around its axle 85 from the locked position of FIG. 4 into the unlocked position of FIG. 7, while overpowering the contrary urging of the spring 93.

The lock cylinder 94 may be one of at least two different types. For example, the lock cylinder may be operated by a key 98 (FIG. 3) which cannot be removed unless it is in the vertical plane. This assures that the handle 43 will always be positively prevented from moving upwardly away form the casing 63 if said handle 43 has been moved into its latched position where the lateral extensions (FIG. 8) on the leg 82 have come into bearing engagement with the upper surface of the top wall 65. That is, with the upper leg 82 bearing against the top wall 65 of the casing 63 the hook 89 will automatically move into its locked position of FIG. 4 due to urging by the spring 93.

On the other hand, the lock cylinder 94 may be of the type wherein the key can be removed after the lock has been rotated 90.degree., as appearing in FIG. 2. In such case, the crank 96 and its pin 97 acting through the catch lever, will continue to hold the catch arm 87, away from engagement with the portion 61 of the handle 43. In that case, the handle 43 can be freely moved between positions where the bolt 47 is in and out of engagement with the catch pin 29.

It will be seen that the C-shaped portion 61 can open radially inwardly, relative to the axle 30, and produce the same results provided that the catch lever 86 is mounted upon the opposite side, namely the left side, of the C-shaped portion 61, as it appears in FIG. 5.

OPERATION

The operation of the door latch and lock structure described above will be apparent from such description to a person of ordinary skill in the manufacture of truck door latches and locks. However, primarily for the purpose of convenience, the latch and lock operation will now be summarized.

When it becomes desirable to unlatch the assembly 11, the key 98 (FIG. 2) is turned 90.degree. in the clockwise direction, whereby the hook 89 is moved sidewardly away from the lower leg 78 of the C-shaped portion 61, as shown in FIG. 7. The C-shaped portion 61 can now be moved upwardly away from the casing so that the handle 43 (FIG. 1) can be raised and pivoted around the axle 30, whereby the hook 49 of latch bolt 47 is moved from beneath the pin 29. After the bolt 47 is released from the pin 29, continued counterclockwise movement of the handle 43 brings the flange 57 (FIG. 2) into engagement with the hook 56 whereby the handle 43 is held in its unlatched or inoperative position.

When it becomes desirable to relatch the door and lock the handle in latched position, the hook 56 is released from the flange 57 and the handle 43 is rotated in the clockwise direction (FIG. 1) so that the C-shaped portion 61 can move through the opening 76 in the top wall of the casing 63. During such movement of the handle 43, the hook 49 of the latch bolt 47 slides under and engages the pin 29 in the catch assembly 13. During the downward movement of the handle 43, the door 12 is forced downwardly so that the seal 15 will be in engagement with the bed 14 of the truck van.

As the latch handle 43 is moved into its latched position, the lower leg 78 of C-shaped portion 61 slides down the upper sloped surface of the hook 89, thereby moving the catch arm 87 rightwardly. When the upper leg 82 bears against the casing 63, the spring 93 urges the catch arm 87 in the counterclockwise direction until the hook 89 is in locked position with respect to the C-shaped portion 61. At this point, a release of the hook 89 from the C-shaped portion 61 can be achieved only by placing the proper key in the cylinder 94 and rotating it clockwise.

Although a particular preferred embodiment of the invention has been disclosed above for illustrative purposes, it will be understood that variations or modifications of such disclosure, which come within the scope of the invention are fully contemplated.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In combination, a truck van having a door frame defining an access opening into the interior of said van, a door movably supported on said van and having interior and exterior surfaces, said door being positionable in a closed position wherein it closes said access opening and being movable upwardly into an open position, catch means mounted on the bed of said van, and latch means movably mounted on said door adjacent said exterior surface and coacting with said catch means for holding said door in said closed position, said latch means including a hook-shaped latch bolt swingably mounted on said door and releasably engageable with said catch means, said latch means further including an elongated actuating handle pivotally supported on said door for swinging movement about a pivot axis and coacting with said latch bolt for controlling the movement thereof, said actuating handle being pivotally movable relative to said door between latched and unlatched positions, the improvement comprising:

bracket means fixedly mounted on said door adjacent the exterior surface thereof and projecting outwardly therefrom, said bracket means comprising a boxlike casing cooperating with said exterior surface to define a substantially closed compartment therebetween, said compartment being totally closed except for an opening formed in the top wall of said casing;

said casing also having a front wall which is spaced outwardly from and is substantially parallel to the exterior surface of said door;

said actuating handle having a recessed portion defining a recess therein, the recessed portion of said handle comprising a C-shaped portion fixedly connected to said handle adjacent the free end thereof and defining said recess which extends radially with respect to said pivot axis, the bight and the lower leg of said C-shaped portion projecting through said opening and being totally enclosed within said compartment when said handle is in said latched position, the upper leg of said C-shaped portion abutting the top wall of said casing and overlapping said opening for closing same, whereby said compartment is totally closed when the handle is in said latched position;

lever means disposed within said compartment and pivotally mounted relative to said bracket means, said lever means having a projection means fixedly mounted thereon and disposed for movement between locked and unlocked positions responsive to swinging movement of said lever means, said projection means being disposed within said recess when said projection means is in said locked position and said actuating handle is in its latched position for positively preventing material movement of said handle away from said latched position;

resilient means coacting with said lever means for yieldably urging said lever means in a direction whereby said projection means is automatically moved into said locked position; and

key-operated release means mounted upon said bracket means and engageable with said lever means for pivoting said lever means so that said projection means is moved from its locked position into its unlocked position, said key-operated release means being operated solely by a key and being the sole means for permitting movement of said lever means away from its locked position so as to release said actuating handle, said key-operated release means including a rotatable lock cylinder disposed within said compartment for rotation about an axis which is substantially perpendicular to the front wall of said casing, said lock cylinder being rotatably mounted solely on said front wall and having the key-receiving end thereof projecting through said front wall.

2. In combination, a truck van having a door frame defining an access opening into the interior of said van, a door movably supported on said van and positionable in a closed position wherein said door closes said access opening, said door being movable upwardly into an open position, catch means mounted on the bed of said van, and latch means movably mounted on said door and coacting with said catch means for holding said door in said closed position, said latch means including a hook-shaped latch bolt swingably mounted on said door and releasably engageable with said catch means, said latch means further including an elongated actuating handle pivotally supported on said door for swinging movement about a pivot axis and coacting with said latch bolt for controlling the movement thereof, said actuating handle being pivotally movable relative to said door between latched and unlatched positions, the improvement comprising:

bracket means fixedly mounted on said door adjacent the exterior side thereof, said bracket means defining therein a substantially closed compartment;

said actuating handle having a recessed portion defining a recess therein;

lever means disposed within said compartment and pivotally mounted relative to said bracket means, said lever means having a projection means fixedly mounted thereon and disposed for movement between locked and unlocked positions responsive to swinging movement of said lever means, said projection means being disposed within said recess when said projection means is in said locked position and said actuating handle is in its latched position for positively preventing material movement of said handle away from said latched position;

said bracket means having an opening formed therein and providing communication with said compartment, and said portion of said handle projecting into said opening when said handle is in said latched position, said handle covering and closing said opening when said handle is in said latched position;

resilient means coacting with said lever means for yieldably urging said lever means in a direction whereby said projection means is automatically moved into said locked position; and

key-operated release means mounted upon said bracket means and engageable with said lever means for pivoting said lever means so that said projection means is moved from its locked position into its unlocked position, said key-operated release means being operated solely by a key and being the sole means for permitting movement of said lever means away from its locked position so as to release said actuating handle;

said lever means comprising an L-shaped lever having first and second legs laterally offset from one another and interconnected by a transversely extending intermediate portion which defines the pivot for said lever, said first leg having said projection means fixedly mounted thereon adjacent the free end thereof, and said release means including rotatable crank means disposed in engagement with said second leg.

3. The combination according to claim 2, wherein said recess opens radially relative to the pivot axis of said handle, said lever being mounted for pivoting movement about a second axis which is parallel to said pivot axis, and said release means including a rotatable lock cylinder rotatably mounted on said bracket means for rotation about a third axis which is spaced from but substantially parallel to said second axis.