US3631327A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Devices for sensing relative rotational displacement
Assignee: Linde Material Handling UK Ltd
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Filing: 1970-05-05
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Granted: 1971-12-28
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Expires: 1990-05-05
Abstract
Abstract A device for sensing relative rotation between two members comprises two discs mounted on the members respectively, one disc having two areas of light-polarizing material each disposed opposite a corresponding area of light-polarizing material on the other disc. A light source transmits light through each pair of opposing discs, and two light-sensitive devices are disposed to receive the light transmitted through the pairs of opposing discs respectively. The discs of light-polarizing material are orientated to polarize the light in such planes that when there is rotational displacement from a datum position there is a decrease in the amount of light falling on one device and an increase in the light falling on the other device, the variation depending on the angle of displacement.
Inventors
- 👤 Ivan Salisbury Payne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:50
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/21; G02; G02B; G02B27/00; G02B27/28
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
186 words
A device for sensing the relative rotational displacement between a pair of relatively rotatable members comprising two relatively rotatable elements for rotation with said members respectively, first and second bodies of light-polarizing material on one of said elements, third and fourth corresponding bodies of light-polarizing material on the other element disposed opposite the first and second bodies respectively, a light source located to transmit light through each pair of opposing bodies, and two light-sensitive devices located to receive the light transmitted through the pairs of opposing bodies respectively, the plane of polarization of the third body, in a datum position, being displaced through an acute angle in one sense from the plane of polarization of the first body, and the plane of polarization of the fourth body, in the datum position, being displaced through an acute angle in the opposite sense from the plane of polarization of the second body, so that when relative rotation occurs from the datum position the angle between the polarization planes of one pair of bodies increases and the angle between the polarization planes of the other pair of bodies decreases.
Claim 2
Independent Claim
186 words
A device for sensing the relative rotational displacement between a pair of relatively rotatable members comprising two relatively rotatable elements for rotation with said members respectively, first and second bodies of light-polarizing material on one of said elements, third and fourth corresponding bodies of light-polarizing material on the other element disposed opposite the first and second bodies respectively, a light source located to transmit light through each pair of opposing bodies, and two light-sensitive devices located to receive the light transmitted through the pairs of opposing bodies respectively, the plane of polarization of the third body, in a datum position, being displaced through an acute angle in one sense from the plane of polarization of the first body, and the plane of polarization of the fourth body, in the datum position, being displaced through an acute angle in the opposite sense from the plane of polarization of the second body, so that when relative rotation occurs from the datum position the angle between the polarization planes of one pair of bodies increases and the angle between the polarization planes of the other pair of bodies decreases.
Claim 3
Dependent Claim
26 words
A device according to claim 1 wherein the angles between the polarization planes in the two pairs of bodies are substantially equal in the datum position.
Claim 4
Dependent Claim
39 words
A device according to claim 1 wherein the body of the first and second bodies on one element are parallel and the polarization planes of the third and fourth bodies on the other element are inclined to one another.
Claim 5
Dependent Claim
24 words
A device according to claim 3 wherein the first and second bodies on said one element comprise different portions of a single large body.
Claim 6
Dependent Claim
23 words
A device according to claim 1 wherein each body of light-polarizing material is in the form of a flat panel of such material.
Claim 7
Dependent Claim
24 words
A device according to claim 5 wherein the panels on each element are annular and coaxial with the axis of rotation of the element.
Claim 8
Dependent Claim
12 words
A device according to claim 1 wherein the two elements are coaxial.
Claim 9
Dependent Claim
37 words
A device according to claim 1 including shielding means provided between the two light-sensitive devices for preventing light transmitted by one pair of bodies from falling on the light-sensitive device associated with the other pair of bodies.
Claim 10
Dependent Claim
65 words
A power steering transmission for vehicles comprising: two relatively rotatable members to which relative rotation may be applied manually; a device according to claim 1 connected between the two members; and, light-sensitive devices controlling means for powering the transmission and operative for applying power to the transmission in a manner dependent on the extent and direction of relative rotation displacement applied between the two members.
Claim 11
Dependent Claim
51 words
A poweR steering transmission according to claim 9 wherein the two relatively rotatable members are connected by a torsional coupling so that relative rotation between the members applies a torque to the transmission, said light-sensitive devices controlling said power means in such a manner as to assist the manually applied torque.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |