US3783312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Viscous deceleration damped incremental position motor
Assignee: Kearfott Guidance and Navigation Corp
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Filing: 1973-01-15
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Granted: 1974-01-01
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Expires: 1993-01-15
Abstract
Abstract Damping apparatus for use in a dual position stepper motor is shown. An arm on the motor shaft rotates therewith in a recess formed in a friction plate held for limited movement between two surfaces. Damping is obtained by the arm striking an edge of the recess of the friction plate and moving it slightly to absorb the momentum of the motor and its load. Means are provided to adjust the pressure on the friction plate to allow it to be effective for different motor loads.
Inventors
- 👤 A Schindel
- 👤 D Wojtowicz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:12
CPC Classifications
H; H02; H02K; H02K37/00; H02K37/22
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
123 words
In a stepper motor having a shaft rotatable between two positions in response to selected inputs, apparatus to damp the motion of the shaft when arriving at one of the two positions comprising: a. a friction plate placed against an end of the motor concentric with the motor shaft said friction plate having a pair of projections which have facing edges spaced by an angular amount substantially equal to the angular spacing between the two shaft positions; b. an arm attached to the motor shaft for rotation therewith and positioned so as to rotate between said facing edges; and c. means to hold said friction plate against said end, said means having provisions to adjust the pressure with which said plate is held.
Claim 2
Dependent Claim
123 words
In a stepper motor having a shaft rotatable between two positions in response to selected inputs, apparatus to damp the motion of the shaft when arriving at one of the two positions comprising: a. a friction plate placed against an end of the motor concentric with the motor shaft said friction plate having a pair of projections which have facing edges spaced by an angular amount substantially equal to the angular spacing between the two shaft positions; b. an arm attached to the motor shaft for rotation therewith and positioned so as to rotate between said facing edges; and c. means to hold said friction plate against said end, said means having provisions to adjust the pressure with which said plate is held.
Claim 3
Dependent Claim
39 words
The invention according to claim 1 and further including means to provide at least one projection from said end and an elongated recess in said friction plate fitting over said projection to permit limited rotation of said friction plate.
Claim 4
Dependent Claim
58 words
The invention according to claim 2 wherein said means to provide at least one projection comprises a stop plate secured to said end and having at least one projection thereon and said means to hold said friction plate comprises a cover plate concentric with said friction plate and means to hold said cover plate against said friction plate.
Claim 5
Dependent Claim
59 words
The invention according to claim 3 wherein said holding means comprise a pair of studs screwed into said end and passing through holes in said sTop plate, through slotted holes in the projecting portions of said friction plate and holes in said cover plate, and a Belleville washer and nut screwed onto the end of each of said studs.
Claim 6
Dependent Claim
28 words
The invention according to claim 1 wherein said arm projects in both directions along a diameter of the shaft and said projections on said friction plate are pie-shaped.
Claim 7
Dependent Claim
47 words
The invention according to claim 4 wherein said stop plate contains two pie-shaped projections diametrically opposed and said friction plate contains two pie-shaped recesses on the side of the plate opposite and under said pie-shaped projections of a size slightly larger than said stop plate pie-shaped projections.
Claim 8
Dependent Claim
31 words
The invention according to claim 2 wherein said means to provide at least one projection comprises a pin embedded in said end and said recess in said friction plate is kidney-shaped.
Claim 9
Dependent Claim
67 words
The invention according to claim 7 wherein said end contains a tubular projection having an inside thread at the outermost part, inside of which said friction plate is placed and said means to hold said friction plate comprises at least one friction washer contacting the projections on said plate, a Belleville washer contacting said friction washers and a nut screwed into said threads against said Belleville washer.
Claim 10
Dependent Claim
47 words
The invention according to claim 1 wherein the shaft has a narrow threaded portion on its end forming a shoulder and said arm contains a hole which is placed over said end and held against said shoulder by a nut screwed onto the end of the shaft.
Claim 11
Dependent Claim
14 words
The invention according to claim 1 wherein said friction plate is made of PENLON.
References Cited (Backward Citations)
US2671863A
Cited
US3110830A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |