APPARATUS FOR STACKING OR UNSTACKING CONTAINERS

• US 3,765,546 A
• Filed: 10/06/1971
• Issued: 10/16/1973
• Est. Priority Date: 10/06/1971
• Status: Expired due to Term

• Current Assignee: David E. Westerling
• Original Assignee: David E. Westerling
• Inventors: Westerling, David E.
• Primary Examiner(s): Spar, Robert J.
• Application Number:
  US05/187,042
• Time in Patent Office: 741 Days
• Field of Search: 214/6BA,8.5K,6P,8.5A,8.5R
• US Class Current: 414/795.2
• CPC Class Codes: B65G 59/062 by means of reciprocating or oscillating escapement-like mechanisms
• CPC Class Codes: B65G 60/00 Simultaneously or alternatively stacking and de-stacking of articles
• CPC Class Codes: Y10S 414/112 Group formed or dispensed by reversible apparatus

Abstract

An apparatus which can be converted to either a stacker or an unstacker of relatively heavy objects, such as bins of fruit, that are delivered to and from the apparatus by means of a conveyor. The bins are supported upon dogs which are pivotally mounted upon a pair of carriages positioned at each side of the conveyor. The carriages are slidably mounted upon upright posts and are arranged for joint switch-controlled vertical movement on the posts. This joint movement is provided by vertically extending racks which are attached to the carriages and which are arranged to be driven through pinions affixed to a common horizontal shaft at the top of the apparatus.

Claims

1. Apparatus for stacking or unstacking containers comprising conveying means arranged in a generally horizontal plane, a pair of vertical posts one being mounted adjacent each opposed side of said conveying means, control means for bringing said containers to a position adjacent to said posts, a carriage mounted for vertical movement on each post of said pair of posts, each of said carriages including pivotably mounted lift fingers movable between a first position wherein they project toward said conveying means to receive and support a lower surface of one of said containers and a second position wherein they are out of the path of the containers, a vertically extending rack connected to each of said carriages, each rack extending parallel to and being supported by its associated post for vertical movement relative thereto, each carriage including a mounting frame structure which encompasses the associated post upon which it is mounted whereby all forces other than vertical forces which are imposed on said carriages will be transferred to said posts rather than to said racks, said posts and racks comprising the sole support means for said carriages, a shaft having a pair of pinions thereon arranged to engage said racks, and drive means arranged to rotate said shaft so as to jointly move said carriages and said one container vertically while said container is supported on said lift fingers.

2. Apparatus according to claim 1 including vertically extending guide tracks provided on each of said posts, each of said carriages being provided with inwardly projecting guide means arranged to be received in said tracks.

3. Apparatus according to claim 2 wherein said guide means comprise rollers mounted for free rotary movement.

4. Apparatus according to claim 1 wherein each of said racks extend upwArdly adjacent to one of said posts and wherein said shaft is located in a generally horizontal plane at the top of said apparatus.

5. Apparatus according to claim 4 including roller guide means for supporting the upper end of each of said racks.

6. Apparatus according to claim 1 wherein said lift fingers are pivotally mounted upon said carriages for movement between a first position wherein said fingers extend inwardly in a generally horizontal orientation to engage and support said containers and a second position wherein said fingers are pivoted upwardly so that they are out of the vertical path of travel of said containers in said apparatus.

7. Apparatus according to claim 6 wherein said first position of said fingers is the normal position thereof when said fingers are not in engagement with one of said containers, said fingers being arranged to be pivoted to said second position by engagement with one of said containers upon downward movement of the associated carriages, and control means for operating said drive means so that said apparatus is programmed to stack successive containers delivered thereto by said conveying means.

8. Apparatus according to claim 7 wherein said control means for operating said drive means includes means for sensing the presence of a container on said conveying means between said posts and means for sensing the presence of a container near the upper ends of said posts.

9. Apparatus according to claim 6 wherein said second position of said fingers is the normal position thereof when said fingers are not in engagement with one of said containers, stationary cam means for pivoting said fingers to said first position upon upward movement of the associated carriages, and control means for operating said drive means so that the apparatus is programmed to successively elevate all but the lowermost container in a stack of containers to permit said lowermost container to be moved from said stack by said conveying means until each of the containers in said stack has been individually moved from said apparatus.

10. Apparatus according to claim 9 wherein said control means for operating said drive means includes means for sensing the presence of a container atop the lowermost container in said stack and means for sensing the discharge of the lowermost container from said apparatus.