Latch-Lock Structure

The present invention relates to an improved latch-lock structure for a container.

By way of background, there is in use a plastic hinged container having an exposed resilient latch structure. This latch structure consists of a latch member molded on one part and a keeper molded on the other part. The latch is exposed and it can be digitally pressed to unlatch the container. However, it is desirable to prevent unauthorized unlatching of the container.

It is the object of the present invention to provide a housing structure for use with the existing exposed latch structure of a container to thereby prevent unauthorized unlatching of the container.

Another object of the present invention is to provide a lock structure for a latch of a container which utilizes a key for unlatching the latch but which causes the latch to spring back to a latching position when the key no longer actuates the unlatching mechanism.

A further object of the present invention is to provide an improved latch-lock structure which includes a spring arrangement which biases the parts of the container to an open position as soon as the latching structure is unlatched. Other objects and attendant advantages of the present invention will readily be perceived hereafter.

The present invention relates to a lock structure comprising a first housing for concealing a latch, a second housing, a chamber in said second housing for surrounding a latch retainer, and a key-operated latch-moving member on said first housing for moving said latch out of latching engagement with said latch retainer.

The present invention also relates to a container having a first container part, a first side on said first container part, a second container part which is movable relative to said first container part, a second side on said second container part, a latch on said first side, and a latch retainer on said second side for retaining said latch when said first and second container parts are in a closed position: a lock structure on said container comprising a first housing on said first side, a second housing on said second side, a chamber in said second housing containing said latch retainer, and a latch-moving member on said first housing positioned adjacent said latch.

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:

FIG. 1 is a plan view of a container having the improved lock ,structure mounted thereon;

FIG. 2 is a side elevational view taken substantially in the direction of arrows 2--2 of FIG. 1;

FIG. 2A is a fragmentary perspective view, partially in cross section, of the latch which is formed integrally with the lip of the cover of the container;

FIG. 3 is an end elevational view taken substantially in the direction of arrows 3--3 of FIG. 1;

FIG. 4 is a fragmentary cross sectional view taken substantially song line 4--4 of FIG. 3 and showing the various components of the latch in a locked condition and also showing the tip of the key poised for entry into the lock housing;

FIG. 4A is a fragmentary cross sectional view similar to FIG. 4 but showing the latch of the lock moved to an unlatched condition which permits opening of the container;

FIG. 5 is a cross sectional view taken substantially along line 4--4 of FIG. 3 but showing the upper portion of a container moved away from the lower portion and showing the positions which the various parts assume after the container has been opened;

FIG. 6 is a view of the end of the key taken substantially in the direction of arrows 6--6 of FIG. 4;

FIG. 7 is a fragmentary cross sectional view taken substantially along line 7--7 of FIG. 5 and showing the manner in which the upper housing is secured to the side of the upper part of the container;

FIG. 8 a fragmentary cross sectional view taken substantially along line 8--8 of FIG. 5 and showing how the lower housing is secured to the side of the lower part of the container;

FIG. 9 is a fragmentary cross sectional view taken substantially along line 9--9 of FIG. 5 and showing the cam structure mounted on the key-receiving member and also showing the springs for biasing the housing apart when the latch is unlatched;

FIG. 10 is a fragmentary cross sectional view taken substantially a long line 10--10 of FIG. 9;

FIG. 11 is a fragmentary cross sectional view taken substantially along line 11--11 of FIG. 10 but showing the lock housing in a sprung-open condition;

FIG. 12 is a fragmentary view of a portion of FIG. 9 and showing the cam moved in a counterclockwise direction to an unlatching position;

FIG. 13 is a fragmentary view similar to FIG. 12 and showing the cam moved clockwise to an unlatching position; and

FIG. 14 is a side elevational view of a key which is used to unlatch the latch.

The lock structure 10 of the present invention is shown mounted on prior art container 11 consisting of a bottom part 12 and a top part or cover 13 which is hingedly mounted to bottom part 12 by a pair of hinges 14 which are adjacent container sides 15 and 17.

The lock structure 10 of the present invention includes a lower housing 19 mounted on container side 20 and an upper housing 21 mounted on container side 22. More specifically upper housing 21 comprises a block of plastic which is contoured as shown at 23 in FIG. 2 to fit against both side 22 and lip 16 formed integrally with side 22. Housing 21 is secured to side 22 by a pair of bolts 24 (FIG. 7) which extend through side 22. Lower housing 19 is attached to side 20 by bolts 25 (FIG. 8) which bear against bar 27 on the inside of side 20 and extend into sides 29 of lower housing 19.

The parts of the prior art container 11 are fabricated from molded plastic, and container side 22 includes a flexible resilient latch 30 which is formed integrally with and is an extension of lip 16 (FIGS. 2A, 4A and 5). Latch 30 normally assumes an unbiased position shown in FIGS. 4 and 5. A U-shaped latch retainer or keeper 31 (FIGS. 4, 5 and 8) is molded integrally with container side 20, and it includes a cross side 33 and sides 32 (FIG. 8) which extend outwardly from side 20. When the container part 13 moves toward container part 12 to a closed position, the cam surface 34 (FIG. 5) of barb 36 of latch 30 will engage the top 35 of keeper cross side 33 and be biased to the left as cam surface 34 rides along keeper side 33 until the container reaches a closed position, whereupon the latch 30 will spring back to the position shown in FIG. 4 wherein the latch surface 37 of barb 36 underlies keeper side 33, which prevents the container part 13 from being opened away from container part 12 unless latch 30 is moved to the position of FIG. 4A. As noted above, the container, latch structure and keeper are all prior art. The lock structure consisting of housings 19 and 21 and related parts have been added to this prior structure to prevent unauthorized unlatching of the container by digitally pressing exposed latch 30 from its position of FIG. 4 to its position of FIG. 4A.

The lock structure 10 includes the lower housing 19 which has a chamber 26 which houses latch retainer 31 within walls 29, 29' and 30' (FIGS. 5 and 8). Upper housing 21 conceals latch 30 and mounts a key-receiving member or bolt 37 which is pivotally mounted in wall 39. More specifically, square shank 40 of bolt 37 is held in cylindrical sleeve 44 which is pivotally mounted in bore 41 in wall 39. A latch-moving member in the form of a cam 42 is keyed to the square portion 43 of shank 37, and it lies against planar substantially rectangular surface 46' (FIGS. 5, 9 and 10) of upper housing 21. A spring clip 45 retains cam 42 on bolt 37. Key-receiving member 37 includes a head 47 which has a curvilinear groove 49 therein. Head 47 is recessed within bore 46 where it cannot be grasped by a plier or wrench. Cam 42 includes an edge 50 (FIGS. 9, 12 and 13) which normally lies parallel to the elongated portion 51 of latch 30.

A key 48 (FIG. 14) is used to unlock latch 30. Key 48 includes a handle 46' and a shank 48' which mounts a sleeve 49' (FIGS. 4, 6 and 14) surrounding curvilinear ridge 53 which fits into curvilinear groove 49. Sleeve 49' fits closely into bore 46, and, in operation sleeve 49' is inserted into bore 46 and turned until ridge 53 falls into groove 49. After the curvilinear ridge 53 of key 48 is received in curvilinear groove 49 and the key 48 is turned to pivot key-receiving member 37, cam 42 can be moved from its normal position of FIG. 9 to either of the positions of FIGS. 12 or 13, depending on the direction in which key-receiving member 37 is pivoted. This moves latch 30 from the position of FIG. 4 to the position of FIG. 4A wherein the end barb 36 of the latch is disengaged from keeper side 33 so that container part 13 can move upwardly to the position of FIG. 5. The movement of latch 30 from the position of FIG. 4 to the position of FIG. 4A is opposed by spring 52 which has been added along with housing 19. Spring 52 is retained in position by spring extension 56 which is held against container side 20 by bar 27. The bend 58 of spring 52 passes through hole 66 in container part 12 and through hole 68 in housing 19 (FIG. 5).

The pivotal movement of cam 42 is limited by boss 53 which protrudes outwardly from plate 54 which is screwed to housing wall 55 by screws 57 (FIG. 9). It can thus be seen that the ends 59 and 60 will engage boss 53 to define the limit of pivotal movement of cam 42. In each extreme limit of movement, either the edge portion 62 (FIG. 13) or the edge portion 63 (FIG. 12) engages the side 64 of resilient latch member 30. Thus, when the key 48 no longer exerts a pivotal force on key-receiving member 37, the natural resilience of latch 30 aided by the biasing force of spring 52 will move cam 42 from either of its positions of FIGS. 12 or 13 back to the neutral position of FIG. 9.

Once latch 30 has been released from its engagement with keeper 31 as described above relative to FIGS. 12 and 13, springs 65, which are housed in bores 67 and press against surfaces 69 (FIGS. 5 and 8) at the tops of sides 29 of housing 19, will spring upper housing 21 away from lower housing 19 (FIG. 11). Springs 65 are retained in bores 67 by having their upper turns distorted so as to frictionally engage the sides of the bores in which they are located.

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: