Test head manipulator configured to address uncontrolled test head rotation

Patent metadata

Field	Value
Publication number	US-11498207-B2
Application number	US-202117144937-A
Country	US
Kind code	B2
Filing date	Jan 8, 2021
Priority date	Jan 8, 2021
Publication date	Nov 15, 2022
Grant date	Nov 15, 2022

Abstract

An example test head manipulator includes a tower having a base and a track, where the track is vertical relative to the base, and arms to enable support for the test head. The arms are connected to the track to move the test head vertically relative to the tower, and the arms are configured to control rotation of the test head. Each of the arms includes a cam that is rotatable, and at least one plunger in contact with the cam and that is configured to contact the test head. Rotation of the cam is controllable to move the at least one plunger to offset an uncontrolled rotation the test head.

First claim

What is claimed is:

1. A test head manipulator comprising:
a tower having a base and a track, the track being vertical relative to the base; and
arms to enable support for the test head, the arms being connected to the track to move the test head vertically relative to the tower, the arms being configured to control rotation of the test head, each of the arms comprising (i) a cam that is rotatable and (ii) at least one plunger in contact with the cam and that is configured to contact the test head, where rotation of the cam is controllable to move the at least one plunger to offset an uncontrolled rotation of the test head;
wherein the at least one plunger comprises:
a first plunger on a first side of the cam, the first plunger comprising a first roller that contacts the cam;
a second plunger on a second side of the cam, the second plunger comprising a second roller that contacts the cam: and

wherein the cam is controllable to rotate relative to the first plunger and the second plunger so that, at different angles of rotation. different parts of the cam contact the first plunger and the second plunger causing movement of at least one of the first plunger or the second plunger that is transferred to the test head to offset the uncontrolled rotation.

2. The test head manipulator of claim 1 , wherein cross-sections of the cam have radii that vary continuously along at least part of each cross-section.

3. The test head manipulator of claim 1 , wherein each of the at first plunger and the second plunger comprises:
a ball configured to contact a part of the test head, the ball being rotatable at least in tumble and theta directions relative to an ann of the test head manipulator.

4. The test head manipulator of claim 3 , wherein the at least one plunger comprises:
a housing to house the ball;
a shaft to which the housing connects; and
at least one spring that is at least partly compressible to change a longitudinal dimension of the at least one plunger.

5. The test head manipulator of claim 4 , wherein the at least one plunger comprises:
a roller to contact the cam, the roller being configured to transmit displacement produced by rotation of the cam to the plunger.

6. The test head manipulator of claim 1 , further comprising:
a handle, at least a part of which is external to an arm of the test head manipulator, the handle connecting mechanically to the cam, the handle being controllable to rotate the cam manually.

7. The test head manipulator of claim 1 , wherein the cam is controllable to move the at least one plunger to offset a ±1.5° rotation of the test head or less.

8. The test head manipulator of claim 1 , further comprising:
one or more motors to drive movement of the arms along the track.

9. The test head manipulator of claim 1 , wherein the cam comprises a first angular structure and a second angular structure that are rotatable about a same axis, the first angular structure having a first radius that changes along part of the first angular structure, and the second angular structure having a second radius that changes along at least part of the second angular structure.

10. The test head manipulator of claim 9 , wherein the first radius increases in a first angular direction, and the second radius that increases in a second angular direction, the first angular direction being opposite to the second angular direction.

11. The test head manipulator of claim 10 , wherein at a maximum radius of the first angular structure, the first angular structure comprises a straight edge discontinuity connecting the maximum radius to a minimum radius of the first angular structure; and
wherein at a maximum radius of the second angular structure, the second angular structure comprises a straight edge discontinuity connecting the maximum radius to a minimum radius of the second angular structure.

12. A test head manipulator comprising:
a tower having a base and a track. the track being vertical relative to the base; and
arms to enable support for the test head, the arms being connected to the track to move the test head vertically relative to the tower. the arms being configured to control rotation of the test head, each of the arms comprising (i) a cam that is rotatable and (ii) two plungers in contact with the cam and configured to contact the test head, where rotation of the cam is controllable to move the two plungers to offset an uncontrolled rotation of the test head;
wherein the two plungers are oriented in opposite directions relative to the test head such that each of the two plungers is configured to contact a different part of the test head;
wherein rotation of the cam causes longitudinal movement of the two plungers, where the longitudinal movement of at least one of the two plungers is transferred to the test head to offset the uncontrolled rotation;
wherein the two plungers comprise:
a first plunger on a first side of the cam, the first plunger comprising a first roller that contacts the cam; and
a second plunger on a second side of the cam, the second plunger comprising a second roller that contacts the cam:

wherein the cam is in between the first plunger and the second plunger; and
wherein the cam is controllable to rotate relative to the first plunger and the second plunger so that, at different angles of rotation, different parts of the cam contact the first plunger and the second plunger.

13. The test head manipulator of claim 12 , wherein the cam comprises a first angular structure and a second angular structure that are rotatable about a same axis, the first angular structure having a first radius that changes along part of the first angular structure, and the second angular structure having a second radius that changes along at least part of the second angular structure.

14. The test head manipulator of claim 13 , wherein the first radius increases in a first angular direction, and the second radius that increases in a second angular direction, the first angular direction being opposite to the second angular direction.

15. The test head manipulator of claim 14 , wherein at a maximum radius of the first angular structure, the first angular structure comprises a straight edge discontinuity connecting the maximum radius to a minimum radius of the first angular structure; and
wherein at a maximum radius of the second angular structure, the second angular structure comprises a straight edge discontinuity connecting the maximum radius to a minimum radius of the second angular structure.

16. The test head manipulator of claim 15 , wherein the first angular structure and the second angular structure are each constrained to rotation that is less than 360° .

17. The test head manipulator of claim 15 , wherein the first angular structure and the second angular structure are each constrained to rotation that is between 0° and 145° .

18. The test head manipulator of claim 12 , wherein the first plunger and the second plunger are about 180° apart such that the first plunger is oriented towards a top of an arm of the test head manipulator and the second plunger is oriented towards a bottom of the arm.

19. A test head manipulator comprising:
a tower having a base and a track, the track being vertical relative to the base: and
arms to enable support for the test head. the arms being connected to the track to move the test head vertically relative to the tower, the arms being configured to control rotation of the test head, each of the arms comprising a cam that is rotatable and at least one plunger in contact with

Assignees

• Teradyne Inc

Inventors

• Silva Isaac N

Classifications

• G01R31/2887

  involving moving the probe head or the IC under test; docking stations (moving single probes G01R1/06705; moving individual probes in multiple probes G01R1/07392) · CPC title

• B25J9/041 Primary

  Cylindrical coordinate type · CPC title

• G01N29/265

  by moving the sensor relative to a stationary material · CPC title

• B25J17/0208 Primary

  Compliance devices · CPC title

• G01N29/225 Primary

  Supports, positioning or alignment in moving situation · CPC title