Chucking device for interchangeable holding of probe pins in a coordinate-measuring instrument

• US 4,649,623 A
• Filed: 05/16/1986
• Issued: 03/17/1987
• Est. Priority Date: 06/03/1983
• Status: Expired due to Fees

• Current Assignee: Carl-Zeiss-Stiftung
• Original Assignee: Carl-Zeiss-Stiftung
• Inventors: Zeeh, Rainer, Schneider, Horst, Neumann, Hans J.
• Primary Examiner(s): Weidenfeld, Gil
• Assistant Examiner(s): Howell, Daniel W.
• Application Number:
  US06/863,866
• Time in Patent Office: 305 Days
• Field of Search: 29/568, 33/172 E, 33/559, 33/558, 33/561, 279/1 M, 409/126, 409/127, 269/8, 335/288, 335/289, 335/290, 335/295
• US Class Current: 483/69
• CPC Class Codes: G01B 7/008 using coordinate measuring machines
• CPC Class Codes: G01B 7/012 Contact-making feeler heads therefor
• CPC Class Codes: H01F 2007/208 combined with permanent magnets
• CPC Class Codes: Y10T 279/23 with magnetic or electrostatic means
• CPC Class Codes: Y10T 29/5107 Drilling and other
• CPC Class Codes: Y10T 483/19 Miscellaneous

Abstract

The invention concerns a receiver (1) in the probe head of a multiple-coordinate measuring machine in which probe-pin combinations (21) can be replaceably chucked with high precision with respect to their position in space. The receiver contains an isostatic three-point support (14) against which the base (15, 16, 17, 18, 19) of the probe-pin combination is drawn by an electrically operated clamping device. The clamping device is coupled with the control computer of the measuring machine so that a probe change can be effected automatically.

In a preferred embodiment, the clamping device consists of a permanent magnet (11) and of an electromagnet (10) by which the field of the permanent magnet (11) can be selectively counteracted or increased to achieve pick-up and release functions. In another embodiment, a motor-driven screw thread performs the pick-up and release functions, and assures that the picked-up probe will unambiguously be drawn into correct isostatic engagement with the three-point support.

Claims

1. In combination, a measuring machine having a well defined working area;

a probe head mounted to said measuring machine and comprising a deflectable part;

said deflectable part carrying an exchangeably mounted probe-pin combination, said probe-pin combination being provided with a connecting member of magnetic-flux-conducting material;

a reference support on the deflectable part of said probe head and an electrically operated magnetic clamping device adapted to draw said connecting member against said reference support , said magnet clamping device comprising a permanent magnet core with a polarized end adjacent the magnetic flux-conducting material of said connecting member, and an electrical winding around said core; and

a

magazine arranged in said working area

and having a location for machine controlled storage of said probe-pin combination , said reference support having means engageable with said connecting member in such manner as to unequivocally determine its position in the probe head, whereby (1) upon excitation of said winding in the direction to oppose the polarized flux in said core, the probepin combination may be released from the clamping device and in a controlled storage location, (2) upon excitation of said winding in the direction to add to the polarized flux in said core, the probe-pin combination may be picked up by the clamping device from a controlled storage location, and (3) upon de-energizing said winding the probe-pin combination may be retained in its unequivocally determined position solely by attraction of said permanent magnet to the connecting member of the involved probe-pin combination.