Fastener stretch measurement fixture
AssigneeToyota Motor Engineering & Manufacturing North America, Inc.
InventorChristopher T. Clark
Life of this patent
Estimating the term…
Abstract
Fixtures and methods are described herein to measure fastener stretch after fastener application. The measurement fixtures may include fastener contacting portions having contact plates that may move orbitally about a measurement shaft to allow contact plates to abut against non-parallel end surfaces of a fastener. The fixtures may also include datum assemblies that have datum plate mounted in fixed relation to the contacting portions that allow for measurements to be made between the datum plates. Adjustable dials may be included to transfer rotational movement of the dial to translation movement of the contacting portions. Measurement fixtures may further include a frame and mounting portions.
Claims19
A fastener stretch measurement fixture, comprising:
- a first contact portion and a second contact portion, each configured to abut against an end of a fastener;
- an adjusting portion configured to adjust the position of the first contact portion relative to the second contact portion;
- and
- a first datum plate and a second datum plate, wherein the first datum plate is attached in fixed relation to the first contact portion and the second datum plate is attached in fixed relation to the second contact portion, each datum plate having a datum face,
- wherein each contact portion includes:
- a mounting shaft;
- a swivel joint having a first end and a second end, the first end attached to the mounting shaft;
- and
- a contact plate having a contact face, wherein the contact plate is attached to the second end of the swivel joint such that the contact plate may be moved orbitally relative to a longitudinal axis of the mounting shaft.
A fastener stretch measurement fixture, comprising:
- a first contact portion and a second contact portion, each configured to abut against an end of a fastener, wherein each contact portion comprises a contact plate, a swivel joint, and a mounting shaft, a first portion of the swivel joint being attached to the mounting shaft and a second portion of the swivel joint being attached to the contact plate allowing for orbital movement of the contact plate about a longitudinal axis of the mounting shaft;
- a first adjusting portion and a second adjusting portion, each adjusting portion comprising a rotatable dial configured to adjust the position of the contact portions relative to each other upon rotational movement of the dial;
- and
- a first datum plate and a second datum plate, wherein the first datum plate is attached in fixed relation to the first contact portion and the second datum plate is attached in fixed relation to the second contact portion, each datum plate defining a substantially planar datum face.
A method for measuring fastener stretch, comprising the steps of:
- positioning a measuring fixture around a fastener such that a first contact portion of the measuring fixture faces a first end of the fastener and a second contact portion of the measuring fixture faces a second end of the fastener;
- abutting a first contact face of the first contact portion against the first end of the fastener and a second contact face of the second contact portion against the second end of the fastener;
- measuring a first distance between a first datum plate and a second datum plate, wherein the first datum plate is attached in fixed relation to the first contact portion and the second datum plate is attached in fixed relation to the second contact portion;
- removing the fixture from the fastener;
- tightening the fastener;
- repositioning the measuring fixture around the fastener such that the first contact portion of the measuring fixture faces the first end of the fastener and the second contact portion of the measuring fixture faces the second end of the fastener;
- abutting the first contact face of the first contact portion against the first end of the fastener and the second contact face of the second contact portion against the second end of the fastener;
- measuring a second distance between the first datum plate and the second datum plate;
- and
- determining a difference between the first distance and second distance.
A fastener stretch measurement fixture, comprising:
- a first contact portion having a first mounting shaft and a first contact plate orbitally connected to the first mounting shaft via a first swivel joint;
- a second contact portion having a second mounting shaft and a second contact plate orbitally connected to the second mounting shaft via a second swivel joint;
- an adjusting portion configured to adjust the position of the first contact plate relative to the second contact plate;
- and
- a first datum plate and a second datum plate, wherein the first datum plate is attached in fixed relation to the first contact plate and the second datum plate is attached in fixed relation to the second contact plate.
Dependencies are inferred from the claim text.