Sensing system for coordinate measuring equipment

• US 5,884,410 A
• Filed: 12/17/1996
• Issued: 03/23/1999
• Est. Priority Date: 12/21/1995
• Status: Expired due to Term

• Current Assignee: Carl Zeiss Industrielle Messtechnik GmbH (Carl-Zeiss-Stiftung)
• Original Assignee: Carl-Zeiss-Stiftung
• Inventors: Prinz, Reinhard
• Primary Examiner(s): Fulton, Christopher W.
• Application Number:
  US08/767,887
• Time in Patent Office: 826 Days
• Field of Search: 33/559, 33/560, 33/561, 33/556, 33/557, 33/558, 33/503
• US Class Current: 33/559
• CPC Class Codes: G01B 7/012 Contact-making feeler heads therefor

Abstract

A sensing system has a sensor arranged in the immediate neighborhood of a contacting shaped body. The sensor is connected to a circuit which is likewise arranged in the neighborhood of the contacting shaped body and emits electromagnetic radiation when the sensor responds to contact by the contacting shaped body with a surface to be measured.

Claims

1. A sensing system for coordinate measuring equipment, comprising:

a sensing head (1) with a tracer pin (12a, b, c) that is deflectable with respect to said sensing head,

a contact body (13a, b, c) arranged for contacting a surface to be measured and arranged at a first end of said tracer pin,

a sensor (16, 26,

     36) arranged at said first end of said tracer pin in the neighborhood of said contact body, and

a circuit (17, 27,

     37) connected to said sensor and arranged at said first end of said tracer pin in the neighborhood of said contact body, wherein said circuit (17, 27,

     37) is arranged to emit an electromagnetic radiation when said sensor (16, 26,

     36) responds to contact by said contact body (13a-c) with said surface to be measured.

2. The sensing system according to claim 1, wherein said sensor (16, 26, 36) comprises a piezoelectric crystal.

3. The sensing system according to claim 1, wherein said circuit (17, 27, 37) comprises a high frequency circuit.

4. The sensing system according to claim 3, wherein said circuit (17, 27, 37) operates at frequencies above 10 MHz.

5. The sensing system according to claim 1, wherein said coordinate measuring equipment comprises a sensing head, a measuring arm, control electronics for said coordinate measuring equipment and a receiver circuit (20) for detection of said electromagnetic radiation arranged in said sensing head or said measuring arm or said control electronics.

6. The sensing system according to claim 5, wherein said coordinate measuring system further comprises a mount for a resiliently mounted portion of said sensing head, a switch or a switch contact (5, 7) associated with said mount, and a logic circuit (21) connected to said switch or switch contact (5, 7) and to said receiver circuit (20).

7. The sensing system according to claim 1, further comprising an energy store (15, 25, 35) arranged in the neighborhood of said contact body, and connected to said circuit (17, 27, 37).

8. The sensing system according to claim 7, wherein said energy store (25) comprises a solar cell and a capacitor that is recharged by means of said solar cell.

9. The sensing system according to claim 7, wherein said energy store (25) comprises a piezoelectric crystal and a capacitor that is recharged by means of said piezoelectric crystal.

10. The sensing system according to claim 1, wherein at least one of said sensor (36) and said circuit (37) is arranged in a recess in said contact body (13c).

11. A process for generation of a contacting signal during contact sensing of surfaces with a sensing head of coordinate measuring equipment, comprising:

contacting a surface to be measured with a contact body of said sensing head,

at least partially converting impact energy produced during contact between said surface and said contact body into electromagnetic radiation, and

transmitting said electromagnetic radiation by radio without a further energy source.

12. The process according to claim 11, wherein said conversion of impact energy into electromagnetic radiation takes place in the neighborhood of said contact body.

13. A sensing system for coordinate measuring equipment, comprising:

a sensing head (1) with a tracer pin (12a, b, c) that is deflectable with respect to the sensing head,

a contact body (13a, b, c) arranged for contacting a surface to be measured and arranged at a first end of the tracer pin,

a sensor (16, 26,

     36) arranged at said first end of said tracer pin in the neighborhood of said contact body,

a circuit (17, 27,

     37) connected to said sensor and arranged at said first end of said tracer pin in the neighborhood of said contact body, wherein said circuit (17, 27,

     37) is arranged to emit an electromagnetic radiation when said sensor (16, 26,

     36) responds to contact by said contact body (13a-c) with said surface to be measured, and

an energy store arranged at said first end of said tracer pin in the neighborhood of said contact body and connected to said circuit (17, 27,

     37), wherein said energy store (25) comprises a solar cell and a capacitor that is recharged by means of said solar cell.

14. A sensing system for coordinate measuring equipment, comprising:

a sensing head (1) with a tracer pin (12a, b, c) that is deflectable with respect to the sensing head,

a contact body (13a, b, c) deflectable with respect to the sensing head,

a sensor (16, 26,

     36) arranged at said first end of said tracer pin in the neighborhood of said contact body,

a circuit (17, 27,

     37) connected to said sensor and arranged at said first end of said tracer pin in the neighborhood of said contact body wherein said circuit (17, 27,

     37) is arranged to emit an electromagnetic radiation when said sensor (16, 26,

     36) responds to contact by said contact body (13a-c) with said surface to be measured, and

an energy store arranged at said first end of said tracer pin in the neighborhood of said contact body and connected to said circuit (17, 27,

     37), wherein said energy store (25) comprises a piezoelectric crystal and a capacitor that is recharged by means of said piezoelectric crystal.