Method and system for picking and placing vessels

Abstract

A method and system for picking and placing vessels are provided. The system includes a gripper assembly mounted on a positioning mechanism. The gripper assembly includes a cylinder, a plurality of flexible gripping members extending from the cylinder in a spaced-apart relationship for receiving therebetween a vessel and holding it by friction, a piston slideably inserted inside the cylinder, and a plunger connected to and movable with the piston and extending between the gripping members for engaging the vessel. The method includes the steps of positioning the gripper assembly, picking up and transferring a vessel, and placing, seating and releasing the vessel. The contents of the vessel may also be mixed simultaneously during the transferring of the vessel.

1 . A gripper assembly for picking and placing vessels, comprising: 
 a. a cylinder having an end rim; and    b. at least two gripping members having a spring-like property and extending from said end rim of said cylinder, wherein said gripping members are arranged in a spaced-apart relationship and form an expandable opening for receiving a vessel therebetween,    wherein when the vessel is inserted into the opening, the gripping members are deflected outwardly by the vessel thereby generating a frictional force between the vessel and the gripping members sufficient to hold the vessel.    
     
     
         2 . The gripper assembly of  claim 1 , wherein when the vessel is released from the opening, the gripping members are restored to their initial configurations.  
     
     
         3 . The gripper assembly of  claim 1 , wherein the gripping members each have a chamfered bottom end for receiving a misaligned vessel.  
     
     
         4 . The gripper assembly of  claim 1 , further comprising a plunger connected to and movable with a piston, wherein the piston is slidably disposed inside the cylinder, and the plunger extends from the piston towards the expandable opening, having one end adapted for engaging the vessel.  
     
     
         5 . The gripper assembly of  claim 4 , further comprising an actuating means for actuating said piston to push said plunger for releasing said vessel from said expandable opening.  
     
     
         6 . The gripper assembly of  claim 4 , further comprising a detecting means for detecting whether the vessel is received or released, wherein said detecting means comprises a magnet mounted to and movable with said piston and a sensor fixedly mounted on said cylinder for sensing magnetic field of the magnet.  
     
     
         7 . The gripper assembly of  claim 1 , further comprising a detecting means for detecting whether the vessel is received or released.  
     
     
         8 . The gripper assembly of  claim 1 , further comprising a mixing means for mixing the content of the vessel while it is being held by the gripping members.  
     
     
         9 . The gripper assembly of  claim 1 , further comprising an automatic positioning mechanism for controlling the receiving, transferring, and releasing of the vessel.  
     
     
         10 . The gripper assembly of  claim 1 , further comprising an adaptor for mounting the gripper assembly to a chemical analyzer.  
     
     
         11 . The gripper assembly of  claim 1 , wherein at least one gripping member is made of a semi-rigid flexible material.  
     
     
         12 . A method for picking and placing a vessel, comprising: 
 a. positioning a gripper assembly at a vessel, the gripper assembly including at least two gripping members extending from an end rim of a cylinder arranged in a spaced-apart relationship forming an expandable opening for receiving the vessel therebetween, wherein said gripping members have a spring-like property;    b. picking up said vessel by moving said gripper assembly towards said vessel, wherein said gripping members deflect as said vessel is inserted into the expandable opening; and    c. transferring said vessel as it is held by said gripping members by friction.    
     
     
         13 . The method of  claim 12 , further comprising a releasing step after the transfering step to release the vessel from the expandable opening.  
     
     
         14 . The method of  claim 13 , wherein the gripper assembly further comprises a plunger connected to and movable with a piston, wherein the piston is slidably disposed inside the cylinder, and the plunger extends from the piston towards the expandable opening, having one end adapted for engaging the vessel, and the releasing step is performed by actuating the piston and the plunger to push the vessel out of the expandable opening.  
     
     
         15 . The method of  claim 13 , wherein the releasing step further comprises a step of securing the vessel against a seating at a final position by extending the gripper assembly towards the seating until the vessel is pushed further inside of the expandable opening by the seating, thereby ensuring that the vessel is securely seated.  
     
     
         16 . The method of  claim 12 , further comprising a step of mixing the vessel's content while the vessel is being held by the gripper assembly, and wherein the assembly further comprises a mechanism for performing the mixing step.  
     
     
         17 . The method of  claim 12 , wherein the gripping members each have a chamfered bottom end for receiving a misaligned vessel.  
     
     
         18 . The method of  claim 12 , further comprising a detecting step to detect whether the vessel is inserted into or released from the expandable opening, and wherein the apparatus further comprises a detecting means for detecting whether the vessel is inserted or released.  
     
     
         19 . The method of  claim 14 , wherein the step of picking up said vessel further comprises engaging the vessel with the plunger, and wherein when the vessel is inserted into the expandable opening, the plunger and the piston are pushed to an upper position.  
     
     
         20 . The method of  claim 12 , wherein at least one of the gripping members is made of a semi-rigid flexible material.