Object manipulator and manipulation system

• US 6,435,582 B1
• Filed: 07/31/2000
• Issued: 08/20/2002
• Est. Priority Date: 07/31/2000
• Status: Expired due to Fees

• Current Assignee: Motoman Inc (Yaskawa Electric Corporation)
• Original Assignee: Motoman Inc (Yaskawa Electric Corporation)
• Inventors: DaSilva, Antonio Manuel, Brooks, Eric Cotera
• Primary Examiner(s): BATSON, VICTOR D
• Application Number:
  US09/628,969
• Time in Patent Office: 750 Days
• Field of Search: 294/87.1, 294/94, 294/95, 294/116, 294/115, 414/618, 414/744.8, 901/39
• US Class Current: 294/94
• CPC Class Codes: B25J 15/0052 multiple gripper units or multiple end effectors
• CPC Class Codes: B25J 15/10 with three or more finger members B25J15/0009 takes precedence
• CPC Class Codes: G01N 2035/0406 Individual bottles or tubes
• CPC Class Codes: G01N 2035/0465 Loading or unloading the conveyor
• CPC Class Codes: G01N 35/0099 comprising robots or similar manipulators robots per se B25J
• CPC Class Codes: G01N 35/026 having blocks or racks of reaction cells or cuvettes
• CPC Class Codes: G01N 35/04 Details of the conveyor system G01N35/021 - G01N35/028 take precedence

Abstract

An object manipulation system is provided including a plurality of objects arranged in an object plane, an X-Y positioner, and an object manipulator. The X-Y positioner is arranged to move within an X-Y plane displaced from and parallel to the object plane. The object manipulator is coupled to the X-Y positioner so as to be movable with the X-Y positioner. The object manipulator comprises a rotary turret assembly and a plurality of gripper assemblies. The rotary turret assembly defines a plurality of gripper assembly stations and a gripper pick/place position. The rotary turret assembly is arranged to rotate the gripper assembly stations about a turret axis so as to position a selected one of the gripper assembly stations in the pick/place position. The gripper assemblies are arranged in respective ones of the gripper assembly stations. The rotary turret assembly includes a gripper actuator assembly arranged to cause a gripper assembly positioned in the pick/place position to execute an object pick/place operation on one of the objects in the object plane.

Claims

1. An object manipulator including a gripper assembly arranged to grip and release an object, wherein said gripper assembly comprises:

a plurality of gripper fingers, each of said gripper fingers including

a camming surface portion,

a bearing surface portion, and

an object engaging portion;

a gripper finger pivot assembly arranged to accommodate respective bearing surface portions of said plurality of gripper fingers and wherein said gripper finger pivot assembly is arranged to define respective passages there through, and wherein said respective passages are arranged to accommodate respective bearing surface portions of said plurality of gripper fingers, and wherein each gripper finger has a pivot axis that is parallel to the longitudinal axis of that particular gripper finger; and

a finger spreader positioned to progressively engage respective camming surface portions of said plurality of gripper fingers, wherein said gripper fingers are shaped and said pivot assembly is arranged such that progressive engagement of respective camming surface portions by said finger spreader causes said object engaging portions to be drawn away from each other and such that progressive disengagement of respective camming surface portions and said finger spreader causes said object engaging portions to be drawn towards each other.

2. An object manipulator as claimed in claim 1 wherein said camming surface portion, said bearing surface portion, and said object engaging portion are arranged in succession along each of said gripper fingers.

3. An object manipulator as claimed in claim 1 wherein, upon disengagement of respective camming surface portions and said finger spreader, said object engaging portions converge radially inwards relative to said bearing surface portions.

4. An object manipulator as claimed in claim 1 wherein said bearing surface portion is substantially straight.

5. An object manipulator as claimed in claim 1 wherein said gripper finger pivot assembly is arranged to define respective passages there through, and wherein said respective passages are arranged to accommodate respective bearing surface portions of said plurality of gripper fingers.

6. An object manipulator as claimed in claim 5 wherein:

said bearing surface portions of said plurality of gripper fingers define a circular finger cross section; and

said respective passages define a circular passage cross section slightly larger than said circular finger cross section.

7. An object manipulator as claimed in claim 6 wherein said gripper finger fit comprise a radial portion arranged to define a path of movement of said object engaging portion upon said progressive engagement of said respective camming surface portions.

8. An object manipulator as claimed in claim 1 further comprising a biasing member arranged to urge said object engaging portions towards each other.

9. An object manipulator as claimed in claim 8 wherein said biasing member comprises a constrictive band arranged about said gripper fingers.

10. An object manipulator as claimed in claim 1 further comprising a biasing member arranged to oppose progressive engagement of respective camming surface portions by said finger spreader.

11. An object manipulator as claimed in claim 1 wherein said plurality of gripper fingers are shaped such that, upon progressive engagement of said camming surface portions by said finger spreader, a path of movement of said object engaging portions follows a path of movement of said camming surface portions.

12. An object manipulator as claimed in claim 1 wherein said finger spreader is arranged to initially engage said camming surface portions at a first cross sectional portion thereof and subsequently engage said camming surface at progressively larger cross sectional portions thereof.

13. An object manipulator as claimed in claim 12 wherein said first cross sectional portion and said progressively larger cross sectional portions of said finger spreader are circular.

14. An object manipulator as claimed in claim 1 further comprising an axial stop against which said causing surface portions are arranged to rest upon disengagement of said canning surface portions and said finger spreader.

15. An object manipulator as claimed in claim 14 wherein said axial stop defines an axial stop cross section that is no larger than a cross section of an object to be manipulated.

16. An object manipulator as claimed in claim 14 wherein said axial stop defines a circular axial stop cross section.

17. An object manipulator as claimed in claim 14 wherein said finger spreader is arranged to progressively engage and disengage said camming surface portions by moving along said axial stop.

18. An object manipulator as claimed in claim 1 further comprising a gripper finger bracket arranged along said gripper fingers between respective camming surface portions and respective bearing surface portions, wherein said gripper finger bracket is arranged to define respective finger bracket apertures through which respective gripper fingers move upon progressive engagement and disengagement of said camming surface portions by sad finger spreader.

19. An object manipulator as claimed in claim 18 wherein said respective finger bracket apertures define an arcuate shape.

20. An object manipulator as claimed in claim 1 further comprising:

a gripper finger bracket arranged along sad gripper fingers between respective camming surface portions and respective bearing surface portions, wherein said gripper finger bracket is arranged to define respective finger bracket apertures through which respective gripper fingers move upon progressive engagement and disengagement of said camming surface potions by said finger spreader, and

a biasing member arranged to urge said object engaging portions towards each other, wherein said biasing member comprises a constrictive band arranged about said gripper fingers adjacent said gripper finger bracket.

21. An object manipulator comprising:

a rotary turret assembly defining a plurality of gripper assembly stations and a gripper pick/place position, wherein said rotary turret assembly is arranged to rotate sad gripper assembly stations about a turret axis so as to position a selected one of said gripper assembly stations in said pick/place position; and

a plurality of gripper assemblies arranged in respective ones of said gripper assembly stations, wherein said rotary turret assembly includes a gripper actuator assembly arranged to cause a gripper assembly positioned in said pick/place position to execute an object pick/place operation, wherein said plurality of gripper assemblies are removably secured in respective ones of said gripper assembly stations, and wherein said gripper actuator is arranged to remove a gripper assembly positioned in said pick/place position from one of said gripper assembly stations.

22. An object manipulator as claimed in claim 21 wherein said plurality of gripper assemblies are removably secured in respective ones of said gripper assembly stations through magnetic coupling of said gripper assemblies and said gripper assembly stations.

23. An object manipulator as claimed in claim 21 wherein:

each of said gripper assemblies comprise

a plurality of gripper fingers and

a finger spreader positioned to progressively engage respective camming surface portions of said plurality of gripper fingers, wherein said gripper assembly is arranged such that progressive engagement of respective camming surface portions of said gripper fingers by said finger spreader causes object engaging portions of said gripper fingers to be drawn away from each other and such that progressive disengagement of respective camming surface portions of said gripper fingers and said finger spreader causes said object engaging portions to be drawn towards each other; and

said gripper actuator is further arranged to actuate a finger spreader of a gripper assembly positioned in said pick/place position following removal of said gripper assembly from one of said gripper assembly stations.

24. An object manipulator as claimed in claim 23 wherein said gripper actuator assembly further comprises a spreader actuator arranged to engage a selected finger spreader and move said selected finger spreader along an axis parallel to said turret axis.

25. An object manipulator as claimed in claim 21 wherein said gripper actuator assembly further comprises a Z-axis drive arranged to move a selected gripper assembly along a Z-axis parallel to said turret axis.

26. An object manipulator as claimed in claim 21 wherein each of said gripper assemblies comprise:

a plurality of gripper fingers, each of said gripper fingers including

a camming surface portion,

a bearing surface portion, and

an object engaging portion;

a gripper finger pivot assembly arranged to accommodate respective bearing surface portions of said plurality of gripper fingers; and

a finger spreader positioned to progressively engage respective camming surface portions of said plurality of gripper fingers, wherein said gripper fingers are shaped and said pivot assembly is arranged such that progressive engagement of respective camming surface potions by said finger spreader causes said object engaging portions to be drawn away from each other and such that progressive disengagement of respective camming surface portions and said finger spreader causes said object engaging portions to be drawn towards each other.

27. An object manipulator as claimed in claim 26 wherein, upon disengagement of respective camming surface portions and said finger spreader, said object engaging portions converge radially inwards relative to said bearing surface portions.

28. An object manipulator as claimed in claim 26 further comprising a bar code reader secured to said object manipulator.

29. An object manipulator as claimed in claim 28 wherein said bar code reader defines a field of view encompassing said pick/place position.

30. An object manipulation system comprising:

a plurality of objects arranged in an object plane;

an X-Y positioner arranged to move within an X-Y plane, wherein said X-Y plane is displaced from and parallel to said object plane; and

an object manipulator coupled to said X-Y positioner so as to be movable with said X-Y positioner, wherein said object manipulator comprises

a rotary turret assembly defining a plurality of gripper assembly stations and a gripper pick/place position, wherein said rotary turret assembly is arranged to rotate said gripper assembly stations about a turret axis so as to position a selected one of said gripper assembly stations in said pick/place position, and

a plurality of gripper assemblies arranged in respective ones of said gripper assembly stations, wherein said rotary turret assembly includes a gripper actuator assembly arranged to cause a gripper assembly positioned in said pick/place position to execute an object pick/place operation on one of said objects in said object plane.

31. An object manipulation system as claimed in claim 30 wherein each of said gripper assemblies comprise:

a plurality of gripper fingers, each of said gripper fingers including

a camming surface portion,

a bearing surface portion, and

an object engaging portion;

a gripper finger pivot assembly arranged to accommodate respective bearing surface portions of said plurality of gripper fingers; and

a finger spreader positioned to progressively engage respective camming surface portions of said plurality of gripper fingers, wherein said gripper fingers are shaped and said pivot assembly is arranged such that progressive engagement of respective camming surface portions by said finger spreader causes said object engaging portions to be drawn away from each other and such tat progressive disengagement of respective camming surface portions and said finger spreader causes said object engaging portions to be drawn towards each other.

32. An object manipulator as claimed in claim 31 wherein, upon disengagement of respective camming surface portions and said finger spreader, said object engaging portions converge radially inwards relative to said bearing surface portions.

33. An object manipulator as claimed in claim 30 further comprising a bar code reader secured to said object manipulator.

34. An object manipulator as claimed in claim 30 wherein said bar code reader defines a field of view encompassing said pick/place position.

35. An object manipulation system as claimed in claim 30 further comprising:

at least one additional X-Y positioner arranged to move parallel to said object plane;

an additional object manipulator coupled to each of said additional X-Y positioners so as to be movable with said X-Y positioner.

36. An object manipulator including a gripper assembly arranged to grip and release an object, wherein said gripper assembly comprises:

a plurality of gripper fingers, each of said gripper fingers including

a camming surface portion,

a bearing surface portion, wherein said bearing surface portions of said plurality of gripper fingers define a circular finger cross section; and

an object engaging portion;

a gripper finger pivot assembly arranged to accommodate respective bearing surface portions of said plurality of gripper fingers and wherein said gripper finger pivot assembly is arranged to define respective passages there through, and wherein said respective passages are arranged to accommodate respective bearing surface portions of said plurality of gripper fingers, and wherein the pivot axis of each gripper finger is located in a position that is parallel to said bearing surface portion of said finger; and

a finger spreader positioned to progressively engage respective camming surface portions of said plurality of gripper fingers, wherein said gripper fingers are shaped and said pivot assembly is arranged such that progressive engagement of respective camming surface portions by said finger spreader causes said object engaging portions to be drawn away from each other and such that progressive disengagement of respective camming surface portions and said finger spreader causes said object engaging portions to be drawn towards each other.