Lid Lock For Front End Loader Container

Abstract

Disclosed is a spring loaded member or arm for locking closed and overlapping, dual top lids of a container adapted to be picked up and inverted for unloading by a conventional front end loader type truck. The lock member is automatically moved to lid-releasing position when the pick-up arms of the truck start their initial container-lifting motion.

Description

BACKGROUND OF THE INVENTION

Front end loader trucks for hauling refuse material are now in wide use and, generally, perform their function by utilizing two forwardly extending lift arms, operated from the truck's hydraulic system, to lift and tilt a container over the receptacle formed in the truck body. An example of such front-end loading vehicles is disclosed in U.S. Pat. No. 2,900,096. Conventionally the containers used with such vehicles have hinged doors or lids at their top and difficulty is often encountered in assuring that the lock or latch-type retaining mechanism on the lid permits the lids to open when the container is tilted or inverted. Further, after the unloading operation has been completed, to again latch the container lids in closed position, the operator of the truck must leave the truck cab and manually latch or lock the container lids closed.

The concept of the present invention provides a latching or locking structure for the hinged lids of front end loader containers which is actuated as the container lifting operation begins. This unlocks the lids so that they may open as the container is moved to tilted, unloading position. Return of the container to normal position causes the lids, as they drop closed, to engage the locking arm portion of the structure to return it to locking position.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a fragmentary side view of a container incorporating the lock structure of the present invention and the front end loading vehicle used with the container.

FIG. 2 is an enlarged, fragmentary view of the lock structure shown in FIG. 1.

FIG. 3 is a fragmentary, end view of the structure shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a container, indicated generally at 10, is provided with dual, top lids 11 and 12 which are hinged to the container adjacent their outer margins. Opposite sidewalls of the container carry pick-up pockets 13 which are welded or otherwise rigidly secured to the container's sidewalls and which accommodate the lift arms 14 of a conventional front end loader vehicle indicated generally at 16, the vehicle being capable of moving the container to a tilted or inverted position shown in broken lines in FIG. 1 by means of its lift arm structure 16a and the lift arm moving hydraulic cylinder 16b. It will be understood that the lift arms 14 and the vehicles 16 are of conventional construction and themselves form no part of the present invention.

Referring particularly to FIGS. 2 and 3, the lock structure for the container lids may be seen to include a generally L-shaped lock arm 21 pivotally mounted intermediate its ends at 22 on the container sidewall 23. It will be understood that an identical lock arm 21 is disposed on the opposite sidewall of the container and since the lock arms and accompanying structure are duplicated at each sidewall of the container only one of the arm structures is described and shown in detail.

As will be evident from FIG. 2, the lid 11, nearest the end 13a of the pocket through which the vehicle lift arm enters the pocket, overlaps somewhat the free end, indicated at 12a in FIG. 2, of the hinged lid 12. The overlapping, inclined end portion 11a of the lid 11 is reinforced by means of a transverse bar and is topped by a transverse angle iron 26. The inclined face of the bar 24 rests against the adjacent inclined margin of the free end 12a of the lid 12 when the lids are closed. The horizontally extending flange of the angle iron 26 provides a lock surface which is engaged by the extending portion 21a of the free end of the arm 21. The locking portion 21a of the arm rests upon the upper surface of the horizontal flange of the angle iron 26 when the lids are locked closed. The upper portion 21b of the extending arm is inclined for a purpose to be subsequently explained. The lower free end 21c of the arm 21 is pivotally attached at 27 to a link member 28. The link member 28 is mounted on the container sidewall for rectilinear motion by means of the tube guide 29 which is rigidly attached to the upper surface of the pocket 13. A resilient means, taking the form of tension spring 31 extends between a tab 32 carried by the tube 29 and the tab 33 extending from the adjacent portion of the arm 21. The guide tube overlies an aperture in the upper surface of the pocket 13 and the link member 28 extends into the interior of the pocket adjacent its upper surface as will be evident from FIG. 2.

Interiorly of the pocket 13, the lower end of the member 28 engages the upper face of a trip lever 36 which extends through the pocket 13 and is hinged at 37 to the body of the pocket. At its free end the lever 36 carries a member 38 which extends freely through an aperture in the upper surface of the pocket 13 and carries a head 38a which serves as a stop limiting the downward pivotal movement of the lever 36 within the pocket. In operation, the container will normally have its lids 11 and 12 locked closed with the components of the locking structure and the lids being in their positions shown in FIG. 2. When the pick-up vehicle approaches, the operator need only adjust the pick-up arms 14 of the vehicle to the proper height so that they will enter at 13a into the pick-up pockets 13. The operator need not dismount from the cab of the vehicle to unlock the lids of the container prior to hoisting it to its broken line position of FIG. 1 because of the presence of the locking structure of the present invention. After the lift arms 14 enter the pockets 13, and as the arms move upwardly, the trip lever 36 will be pivotally moved upwardly and this movement of the lever 36 will vertically move upwardly the member 28. This pivots the arm 21 clockwise about the pivot 22, thereby moving the portion 21a of the arm out of locking, overlying engagement with the free end of the lid 11. The lids 11 and 12 are thus freed to swing outwardly to open position under the force of gravity as the container is lifted to its broken line position of FIG. 1. This unlocking motion of the arm 21 takes place against the force exerted by the tension spring 31. As the container is returned from its broken line position to its solid line position of FIG. 1, the lid 12 will drop closed first and the overlapping lid 11 subsequently. The spring 31 moves the locking arm 21 again into lock position. If the lid 11 is delayed in returning to its closed position until after the arm 21 has reached locking position, the inclined surface 21b on the end portion of the locking arm will be engaged by the inclined margin of the lid 11 (defined by the plate 24) and will be cammed momentarily out of lid-overlying position thereby permitting the lid to complete its movement into closed position. After emptying, the container is thus left closed and locked as the operator of the vehicle removes the pick-up arms 14 from the container pockets. The operator of the vehicle need not leave the cab to lock the container lids closed after the container has been unloaded and again deposited in its proper location.

Claims

I claim:

1. A front end loader container having pick-up pockets on two of its opposite sidewalls adapted to be entered by the lift arms of a conventional front end loader vehicle, said container having a pair of lids hinged at opposite ends of the container and with the free end of one lid overlapping somewhat the free end of the other lid, a lock arm pivotally mounted intermediate its ends on a sidewall of said container, one end of said arm being formed to overlie and lock closed the overlapping free end of said one lid, resilient means for urging said lock arm into lid-overlying position, a link member mounted on said container for rectilinear movement and pivotally attached to said arm on the opposite side of the arm pivot from said lid-overlying arm end, a trip lever pivotally mounted to extend through the adjacent one of said pick-up pockets near the upper margin of the pocket and adapted to be engaged by vehicle lift arms as they raise the container, said trip lever engaging said link member whereby as the container is lifted said lock arm is moved out of its lid-overlying position through the motion-transmitting linkage provided by said trip lever and link member.

2. A front end loader container as claimed in claim 1 in which said end of the lock arm overlying said lid is provided with an inclined surface adapted to be engaged by said free end of said overlapping lid as the lid drops to closed position thereby momentarily camming said arm out of lid-overlying position to permit said lid to complete its movement to closed position.

3. A front end loader container as claimed in claim 2 in which said one overlapping lid is nearest the front end loader vehicle.