Linear actuated robotic packaging device and method

Abstract

An end of arm tool that is capable of handling fragile items such as eggs that are packaged in containers (e.g., egg cartons) that require special handling is provided. The end of arm tool comprises pivotal clamps operated by sliding-contact linear actuators and return springs. A retractable gripper for placing divider sheets between packages in the cases may be disposed above the clamps and oriented 90 degrees from the clamps, so that the clamps and gripper may be attached to the same tool without either obstructing the operation of the other. In addition, a method of loading packages, and optionally divider sheets, into cases using the end of arm tool apparatus of the present invention is provided.

1 . An end of arm tool comprising:
 first and second generally opposed clamping members pivotally connected to a base about a first clamping axis and a second clamping axis, respectively, the first and second clamping axes being generally parallel to each other; and   first and second linear thrusters mounted for linear movement relative to the base, the thrusters having contact ends configured to extend toward and press against contact surfaces of the first and second clamping members, respectively, to cause a clamping end of each of the first and second clamping members to pivot generally towards the clamping end of the other of the first and second clamping members, and to produce a clamping force for clamping a package between the first and second clamping ends.   
     
     
         2 . The tool of  claim 1 , further comprising a pusher mechanism adapted to push a package away from the clamping members in a direction transverse to a distance between the clamping members to release the package from the clamping members when the clamping members partially obstruct the movement of the package away from the clamping members. 
     
     
         3 . The tool of  claim 2 , wherein the clamping members comprise retention lips adjacent their clamping ends, the retention lips being a portion of each clamping member turned inwardly toward the opposed clamping member, wherein a distance between the retention lips is shorter than a distance between the ends of the partially obstructed package, and wherein the pusher mechanism is adapted to push the partially obstructed package in the direction transverse to the distance between the retention lips with sufficient force to cause at least one of the package and the clamping members to be deflected and to permit the clamped package to pass between the retention lips and away from the clamping members. 
     
     
         4 . The tool of  claim 1 , wherein the contact ends of the thrusters include generally convex, curved contact faces configured for sliding contact with the contact surfaces of the clamping members. 
     
     
         5 . The tool of  claim 1 , further comprising:
 first and second return springs configured to urge the contact surfaces of the first and second clamping members, respectively, to pivot toward and against the contact ends of the first and second thrusters, respectively, and to urge the first and second clamping ends apart from each other.   
     
     
         6 . The tool of  claim 1 , further comprising:
 third and fourth generally opposed clamping members pivotally connected to the base about a third clamping axis and a fourth clamping axis, respectively, the third and fourth clamping axes being generally parallel to each other and generally orthogonal to the first and second clamping axes; and   third and fourth linear thrusters mounted for linear movement relative to the base, the thrusters having contact ends configured to extend toward and press against contact surfaces of the third and fourth clamping members, respectively, to cause a clamping end of each of the third and fourth clamping members to pivot generally towards the clamping end of the other of the third and fourth clamping members, and to produce a clamping force for clamping a package between the third and fourth clamping ends;   wherein the first, second, third and fourth clamping members are configured to clamp a group of adjacent packages simultaneously between the first and second clamping members and between the third and fourth clamping members.   
     
     
         7 . An end of arm tool comprising:
 first and second clamping members movably mounted to generally opposite sides of a base for movement of generally opposed clamping portions of the first and second clamping members toward each other and into a clamping configuration for clamping a package between the clamping portions and movement of the clamping portions away from each other and out of the clamping configuration to release a package clamped between the clamping portions, wherein the clamping members are adapted to clamp a horizontally oriented package at its ends, where the package is located below the base when the end-of-arm tool is in a clamping orientation; and   a gripping tool movably mounted above the base, the gripping tool having first and second gripping members movable toward each other to grip a cardboard sheet between the gripping members and movable away from each other to release a cardboard sheet gripped between the gripping members;   wherein the end-of-arm tool has a profile defined by the horizontally outermost extents of the base and the clamping members when the end-of-arm tool is in the clamping orientation,   wherein the end-of-arm tool is adapted to be mounted to a robotic arm for movement to and from the clamping orientation and a sheet placing orientation,   wherein the gripping tool is mounted for linear movement to and from a retracted position located substantially within the profile of the end-of-arm tool and an extended position in which at least a portion of the gripping members extends outside the profile of the end-of-arm tool, and   wherein, when the end-of-arm tool is in the cardboard sheet placing orientation and the gripping tool is in the extended position, the at least a portion of the gripping members extends downwardly below the base and the clamping members, and the gripping tool is adapted to grip a substantially vertically oriented cardboard sheet that is located substantially entirely below the base and the clamping members.   
     
     
         8 . The end-of-arm tool of  claim 7 , wherein the end-of-arm tool is configured to be moved from the clamping orientation to the sheet placing orientation and from the sheet placing orientation to the clamping orientation by rotating the end-of-arm tool approximately 90 degrees about a substantially horizontal axis. 
     
     
         9 . A method of packing a package into a case, the method comprising:
 providing an end-of-arm tool mounted to a robotic arm, the end-of-arm tool comprising   first and second generally opposed clamping members pivotally connected to a base about a first clamping axis and a second clamping axis, respectively, the first and second clamping axes being generally parallel to each other, and   first and second linear thrusters mounted for linear movement relative to the base, the thrusters having contact ends configured to extend toward and press against contact surfaces of the first and second clamping members, respectively, to cause a clamping end of each of the first and second clamping members to pivot generally towards the clamping end of the other of the first and second clamping members, and to produce a clamping force for clamping a package between the first and second clamping ends;   operating the robotic arm to move the end-of-arm tool so that a package is located between the clamping members;   extending the linear thrusters to clamp the package between the clamping members;   operating the robotic arm to move the end-of-arm tool to move the package proximate to a desired location in the case; and   retracting the linear thrusters and permitting the clamping members to pivot apart from each other to release the package and place the package in the desired location.