Abstract:
An automatic refuse container latch that is adapted to receive one of the opposed, outwardly-extending portions of a trunnion for a refuse container in order to secure the refuse container to a refuse collection vehicle. The latch comprises a forward stop that is adapted to be secured to the refuse collection vehicle and which forms a part of a channel for slidingly receiving one of the outwardly extending portions of the trunnion. An elongated locking arm is provided that has first and second ends with a pivot connection intermediate the first and second ends. The pivot connection is slidingly secured to an elongated track. A piston actuator is provided comprising a cylinder and a rod, with the rod being movable between a retracted and an extended position. A locking ear is provided for capturing the second end of the locking arm.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This Application is a continuation-in-part of U.S. application Ser. No. 09/824,128, filed Apr. 2, 2001 now U.S. Pat. No. 6,413,031. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to refuse collection vehicles and, more particularly, to an improved automatic refuse container latch for securing a refuse container to the refuse collection vehicle during the emptying of the contents of the container into the vehicle. 
     Large refuse collection containers are commonly used in commercial and high density residential settings. Refuse collected in a container is typically transferred to a refuse collection vehicle by placing an upper edge of the container adjacent a loading edge or sill of the hopper of the refuse collection vehicle. The upper edge of the container includes a trunnion structure, about which the container is pivoted to tip the container so that the contents are discharged into the hopper. The tipping of the container is commonly accomplished with the aid of a lift mechanism, such as a push bar, winch/cable/hook combination, or reeving cylinder, which are well known. 
     For safety reasons, a pair of latch mechanisms is typically used to secure the container to the truck hopper adjacent the sill, each latch mechanism defining an enclosed slot that captures an outwardly-extending portion of the trunnion. Many latch mechanisms require that the container be positioned with respect to the truck so that the trunnion bar extensions are within the slot area to be closed by the latch. It can be difficult to so position the container, due to its weight and/or the unevenness of the surface supporting the container. These difficulties are exacerbated if the latch must be manually closed by the truck operator, as the operator may not have sufficient strength to close the latch and move the trunnion bar into the desired area. 
     Accordingly, it is the principle object of the present invention to provide an improved refuse container latch for use with a refuse collection truck. 
     More specifically, it is an object of the present invention to provide an automatic refuse container latch that safely and securely locks a container to the refuse collection vehicle and that is relatively simple in design and reliable in operation. 
     It is a further object to provide an automatic refuse container latch that is durable and able to withstand heavy use and abuse. 
     It is a still further object to provide an automatic refuse container latch that retracts to an out-of-the-way position when not in use. 
     SUMMARY OF THE INVENTION 
     These objects, as well as others that will become apparent upon reference to the following detailed description and the accompanying drawings, are accomplished by a refuse container latch that is adapted to receive one of the opposed, outwardly-extending portions of a trunnion for a refuse container in order to secure the refuse container to a refuse collection vehicle. The latch comprises a forward stop that is adapted to be secured to the refuse collection vehicle and which forms a part of a channel for slidingly receiving one of the outwardly-extending portions of the trunnion. An elongated track is provided which is secured to the refuse collection vehicle. An elongated locking arm is provided that has first and second ends, with a pivot connection intermediate the first and second ends. This pivot connection is slidingly secured to the elongated track. A piston actuator is provided comprising a hydraulic cylinder and a rod, with the rod being moved between a retracted and an extended position, one of the cylinder and the rod being adapted to be pivotally connected to the refuse collection vehicle and the other of the cylinder and rod being pivotally connected to the first end of the locking arm. A locking ear is provided for capturing the second end of the locking arm. Thus, when the rod moves from its retracted position to its extended position, the pivot connection first slides along the elongated track, the latching arm rotates about the pivot connection to capture one of the outwardly-extending portions of the trunnion and draw the trunnion into the channel. Simultaneously, the locking ear captures the second end of the latching arm to secure the trunnion and the channel. 
     In a preferred embodiment, the track comprises a pair of spaced-apart plates, each having a substantially identical elongated slot for receiving the pivot connection of the latching arm. The latching arm is located between the plates and the pivot connection comprises a transverse shaft that is captured in the slots of the two plates. 
     Additionally, a major portion of the slot or track, beginning with the first end, is generally horizontal, while a minor portion of the slot or track at the second end is generally vertical. Accordingly, the latching arm moves horizontally as the pivot connection travels from the first end of the slot along the major portion of the slot, then rotates about the pivot connection and moves vertically as the pivot connection travels along the minor portion of the slot to the second end of the slot, with the second end of the latching part simultaneously being captured by the locking ear as the pivot connection reaches the end of the minor portion of the slot. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a rear hopper refuse collection truck and a refuse container. 
     FIG. 2 is an enlarged fragmentary perspective view of a portion of the refuse collection truck of FIG. 1 showing an automated refuse container latch according to the present invention. 
     FIG. 3 is a side view of the automated refuse container latch of FIG. 2, showing the latch in its retracted position. 
     FIG. 4 is a side view of the automated refuse container latch of FIG. 2, showing the latch in the extended or locked position. 
     FIG. 5 an enlarged fragmentary perspective view of an alternate embodiment of an automated refuse container latch according to the present invention. 
     FIG. 6 is a side view of the automated refuse container latch of FIG. 5, showing the latch in its retracted position. 
     FIG. 7 is a side view of the automated refuse container latch of FIG. 5, showing the latch in the extended or locked position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning to the figures of the drawings, there is seen in FIG. 1 a perspective view of a rear hopper refuse collection truck, generally indicated by  10 , with which an automated refuse container latch according to the present invention may be advantageously used. The truck  10  includes a hopper portion  12  depending from the truck generally rearward of the rear wheels  14  into which refuse is dumped for compaction. The hopper  12  includes a rearward-facing opening generally defined by sidewalls  16 , a lower loading edge or sill  18 , and an upper edge  20 . Each sidewall  16  includes an extension or ear  22  adjacent the loading sill  18  that cooperates with the container latch to be described in detailed below. 
     Also shown in FIG. 1 is a rollable refuse container  24  having an open end including, on one side, a trunnion bar  26  that has a portion that laterally extends beyond each sidewall of the container, referred to herein as the container arms  28 . The trunnion bar  26  of the container is typically between 1¼, inches to 1¾ inches in diameter and between 77½ inches and 78 inches from end-to-end. 
     As is well known, to empty the container  24  of its contents, the container is positioned with the trunnion bar  26  adjacent the loading edge  18  of the hopper, with the container arms  28  between the sidewall extensions  22 . The container arms  28  are then secured to the hopper  12  and the container  24  is then pivoted about the trunnion  26  by means of e.g., a hydraulically-actuated container push bar  30  (also called a tipper bar or kick bar), a drum winch  32  having a cable and hook (not shown), or a reeving cylinder  33 . The container push bar  30  includes support arms  34  that are pivotally connected to the hopper sidewall  16  by means of posts  36 . The push bar  30  may include lift pads  38  to prevent damage to the container when engaged by the push bar. A dumping cylinder  40  moves the push bar  30  to dump the contents of the refuse container  24 . 
     In keeping with the invention, a hydraulically-actuated refuse container latch, generally designated  42 , is provided at each side of the hopper  12  to form a pocket or channel that securely captures the container arms  28  of the container  24 . As best seen in FIGS. 2-4, the refuse container latch  42  includes a forward stop  44  made of, e.g., forged steel which is secured by welding to the loading sill  18  and sidewall extension  22 . (While only one container latch  42  is shown, it is understood that a container latch is located at each end of the loading sill  18  so that both container arms  28  are securely held prior to tipping the container  24 .) The forward stop  44  may be provided with a reinforcing member  46  of, e.g., square bar stock, on its aft side. Forward stop  44  limits the forward movement of the container arms  28 , and thus the container  24 , into the hopper  12 , while the sidewall extensions  22  prevent excessive movement of a container  24  in a direction lateral to the refuse collection truck  10 . 
     An elongated locking arm  48  is provided that cooperates with the forward stop  44  and sidewall extension  22  to close the pocket or channel after the container arm  28  is located therein. The locking arm  48  is movable by means of an hydraulically-actuated piston cylinder  50  and piston rod  52  between a retracted position (FIG. 3) that is substantially out-of-the-way under the loading sill  18  to an extended, locking position (FIG.  4 ). To this end, the locking arm  48  is mounted for both pivoting and sliding motion to a generally elongated track  54  secured to the bottom of the hopper  12  and/or loading sill  18 . As illustrated, the track  54  includes two substantially-identical, spaced-apart plate members  56 , each having an elongated slot  58 . Each slot  58  includes a generally horizontal major portion  58   a  and a shorter, minor portion  58   b  that is at an angle with respect to the major portion  58   a . The locking arm  48  is disposed between the two plates  56  and includes a transverse shaft  60  intermediate its two ends that is sized to be captured in the slots  58  of the plate members  56 . The shaft  60  is able to both pivot with respect to the plate members  56  and travel along the length of the slot  58 , thus providing for both linear and rotatory motion of the locking arm  48 . 
     A guide member  61 , preferably in the form of a roller, is secured to the track  54  aft of the elongated slot  58 . The guide member  61  underlies the free end of the retracted locking arm  48 . As the locking arm  48  moves along the track, the guide member  61  engages an angled portion  63  of the locking arm  48  to move the free end of the locking arm  48  upward to capture the end of the container arm  28  (FIG.  3 ). 
     To move the locking arm  48  from the retracted position to the extended position, one end of the locking arm  48  is pivotally secured by a clevis  62  to the piston rod  52 , the piston cylinder  50  being pivotally mounted to a bracket  64  secured to the underside of the hopper  12 . When in the extended or locked position, the other end of the locking arm  48  is received in a locking ear  66 . As illustrated, the locking ear  66  is formed integrally with the forwarded stop  44  and includes an aperture for receiving the end of the locking arm  48 . To facilitate the entry of the locking arm  48  into the aperture, the end of the locking arm  48  may be beveled, as shown at  68  in FIG.  2 . The locking ear  66  may also include a reinforcing member  70 , which can be positioned to guide the beveled end  68  of the locking arm  48  toward the aperture in the locking ear. 
     The track  54  is designed so that the locking arm  48  moves first generally horizontally as the pivot connection  60  moves along the major portion  58   a  of the slot  58  from its retracted position (FIG. 3) to an intermediate position. In this intermediate position, the beveled end  68  of the locking arm  48  is aft of the locking ear  66  and the container arms  28  of a container  24 . When the pivot connection  60  reaches the intersection of the major portion  58   a  and the minor portion  58   b  of the slot, the locking arm  48  then pivots about the pivot connection  60  in a clockwise direction (as illustrated) to capture the container arm  28  and draw it toward the forward stop  44 . The locking arm  48  then moves generally vertically as the pivot connection  60  moves along the minor portion  58   b  of the slot so that the beveled end  68  of the locking arm  48  passes through the aperture in the locking ear  66  to close the channel, thus capturing the arm  28  of the trunnion bar  26  (FIG.  4 ). This action is reversed to release the container arms  28  upon retraction of the locking arm  48 . 
     Turning to FIGS. 5-7, there is seen an alternate embodiment of an automatic container latch according to the present invention. To the extent that the structure of FIGS. 5-7 corresponds to that shown in FIGS. 1-4, identical reference numerals are used. 
     In the embodiment of FIGS. 5-7, the guide roller  61  has been eliminated. Instead, the locking arm  48  includes two spaced-apart pivot connections  60   a ,  60   b . In addition, the minor portion  58   b  of the slot  58  has been lengthened. Thus, as the two pivot connections  60   a ,  60   b  move along the track from the retracted position (FIG. 6) to the extended position (FIG.  7 ), pivot connection  60   a  first reaches the intersection of the major portion  58   a  and minor portion  58   b  of the slot  58  and the locking arm  48  then rotates clockwise about the pivot connection  60   a  to capture the container arm and draw it toward the forward stop  44 . The pivot connection  60   a  then travels up the minor portion  58   b  of the slot  58  followed by the second pivot connection  60   b , thus moving the locking arm  48  generally vertically so that the free end of the locking arm  48  is captured by the locking ear  66  to close the channel. To this end, the free end of the locking arm  48  includes a notch  72  that engages a lip  74  on the locking ear  66 . This action is reversed to release the container arms upon retraction of the locking arm  48 . 
     As can be appreciated, the hydraulic pistons for the locking arms can be controlled in a manner well known in the art, with the extension and retraction of both locking arms preferably occurring simultaneously. To further enhance operator safety, the controls for the push bar or winch  32  can also be configured so that the locking arms must first be in their extended, latched position capturing the trunnion bar before the push bar or winch can be operated. 
     Thus, an automated refuse container latch achieving all the objects of the present invention has been provided. While the latch has been described in terms of a preferred embodiment, there is no intention to limit the invention to the same. Instead, the invention is defined by the following claims.