True position probe

• US 5,109,610 A
• Filed: 04/23/1991
• Issued: 05/05/1992
• Est. Priority Date: 04/23/1991
• Status: Expired due to Fees

• Current Assignee: James D. Johnson
• Original Assignee: James D. Johnson
• Inventors: Johnson, James D.
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Wirthlin, Alvin
• Application Number:
  US07/690,060
• Time in Patent Office: 378 Days
• Field of Search: 33/556, 33/557, 33/558, 33/559, 33/560, 33/561, 33/503
• US Class Current: 33/559
• CPC Class Codes: G01B 5/004 for measuring coordinates of points
• CPC Class Codes: G01B 7/004 for measuring coordinates of points

Abstract

The present invention is directed to a contact-type probe for obtaining positional information concerning a workpiece characteristic, simultaneously in more than one positional axis. The probe comprises a probe body for mounting in a machine tool and to which other components may be mounted, a double swivel joint mounted to the probe body and a probe shaft mounted to the swivel and carrying a workpiece contact on one end. In operation, the workpiece contact attached to the probe shaft is moved over the workpiece, and the contact engages a characteristic such as an aperture in the workpiece. The probe body remains in a defined position, while the probe shaft may swivel in two axes to engage the characteristic. The magnitude of displacement necessary for the probe shaft to engage the characteristic may be determined to provide positional information concerning the characteristic.

Claims

1. A contact-type sensing probe comprising:

a probe body having an interior passageway along a longitudinal probe body axis and structured for mounting in a machine tool

a bearing mounted to said probe body having a bearing axis of rotation orthogonal to said longitudinal axis of said probe body;

swivel means having a first end structured to engage said bearing and rotate coaxially with said bearing axis of rotation and a second end having a slot and further having a swivel pin passageway defining a pivot axis of rotation orthogonal to said bearing axis of rotation and said longitudinal probe body axis; and

a probe shaft having a distal end, a proximal end extending into said interior passageway of said probe body and a probe shaft pin passageway structured to be coaxial with and a continuation of said swivel pin passageway in said swivel, said probe shaft being structured to fit into said slot in said swivel and receive a pin extending through said swivel and probe shaft pin passageways such that said probe shaft pivots around said pivot axis;

3. A contact-type sensing probe according to claim 1 wherein said probe body is structured such that a sensing means may be mounted thereon.

4. A contact-type sensing probe according to claim 3 wherein a component of said sensing means is a mechanical dial indicator.

5. A contact-type sensing probe according to claim 3 wherein a component of said sensing means is a linear variable differential transformer.

2. A contact-type sensing probe according to wherein a workpiece contact is attached to said distal end of said probe shaft.

6. A contact-type sensing probe for locating the position of a characteristic simultaneously in at least two axes comprising:

a probe body having an interior passageway along a longitudinal probe body axis, a mounting end structured for mounting in a machine tool, a sensor mounting portion structured to mount a sensing means, and a swivel mounting portion extending from the sensor mounting portion having a face parallel with said probe body axis;

a bearing mounted in said face of said swivel mounting portion and having a bearing axis of rotation orthogonal to said longitudinal axis of said probe body;

a probe shaft having a distal end, a proximal end extending into said interior passageway of said probe body and a probe shaft pin passageway defining a pivot axis;

swivel means having a first end structured to engage said bearing and rotate coaxially with said bearing axis of rotation and a second end having a slot structured to receive and support said probe shaft and having a swivel pin passageway extending on either side of said slot and structured to be coaxial with and a continuation of said probe shaft pin passageway, said passageways structured to receive a pin extending through said swivel and probe shaft pin passageways and defining a pivot axis orthogonal to said bearing axis and said probe body longitudinal axis and around which said probe shaft can pivot; and

sensing means mounted to said probe body and configured to sense the movement of said proximal end of said probe shaft.

7. A contact-type sensing probe according to claim 6 wherein a component of said sensing means is a mechanical dial indicator.

8. A contact-type sensing probe according to claim 6 wherein a component of said sensing means is a linear variable differential transformer.

9. A contact-type sensing probe according to claim 6 wherein a workpiece contact is attached to said distal end of said probe shaft.