Patent US3897695A successfully refreshed from Google Patents.
US3897695A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Linkage system, particularly for aircraft control
Assignee: Lockheed Martin Corp
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Filing: 1974-02-06
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Granted: 1975-08-05
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Expires: 1994-02-06
Abstract
Abstract A linkage, particularly for an aircraft control surface utilizing an arrowhead cam and a follower member. The shape of the arrowhead in cooperation with the location of the pivot points of this cam and of the follower predetermines the output motion of the follower in response to input motion on the arrowhead cam. The linkage produces a variable gain; i.e., a different output response at the follower for the same increment of input motion at different places in the total range of input motion.
Inventors
- 👤 Nels C Rostad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:03
CPC Classifications
G; G05; G05G; G05G7/00; G05G7/02; G05G7/04; Y; Y10; Y10T; Y10T74/00; Y10T74/20; Y10T74/20558; Y10T74/2057; Y10T74/21; Y10T74/2101
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
256 words
In a control linkage for controllably converting an input signal to a variable output signal, the improvement comprising: a dual driving surface cam for providing an input signal and secured for pivotable movement; a follower secured for pivotable movement for providing a variable output signal responsive to said input signal, said follower having dual follower surfaces and a neutral position, said dual follower surfaces being contactable by the respective driving surfaces of said cam, one said follower surface being located upon each side of said neutral position; whereby output motion of said follower in response to input motion of said cam is chartable as an inverted S-shaped curve asymmetrical about the origin, such curve having a relatively low gain portion of response close to the origin on both sides of the origin and a contiguous smoothly connected and smoothly curving, rapidly increasing gain portion at each of its extremities after the low gain portions on both sides of the origin; and feedback force means comprising a pair of lobes on said follower remote from said follower surfaces and extending opposite one another, one to each side of a neutral position substantially centrally thereof, a depressed detent in said follower member at said neutral position, a spring-loaded roller separate from and pivotably mounted adjacent said lobes and normally urged into said detent, whereby the shapes of said lobes define the nature and extent of an increasing feedback force at said cam in response to increasing motion of said cam away from a neutral position in said linkage.
Claim 2
Dependent Claim
256 words
In a control linkage for controllably converting an input signal to a variable output signal, the improvement comprising: a dual driving surface cam for providing an input signal and secured for pivotable movement; a follower secured for pivotable movement for providing a variable output signal responsive to said input signal, said follower having dual follower surfaces and a neutral position, said dual follower surfaces being contactable by the respective driving surfaces of said cam, one said follower surface being located upon each side of said neutral position; whereby output motion of said follower in response to input motion of said cam is chartable as an inverted S-shaped curve asymmetrical about the origin, such curve having a relatively low gain portion of response close to the origin on both sides of the origin and a contiguous smoothly connected and smoothly curving, rapidly increasing gain portion at each of its extremities after the low gain portions on both sides of the origin; and feedback force means comprising a pair of lobes on said follower remote from said follower surfaces and extending opposite one another, one to each side of a neutral position substantially centrally thereof, a depressed detent in said follower member at said neutral position, a spring-loaded roller separate from and pivotably mounted adjacent said lobes and normally urged into said detent, whereby the shapes of said lobes define the nature and extent of an increasing feedback force at said cam in response to increasing motion of said cam away from a neutral position in said linkage.
Claim 3
Dependent Claim
26 words
The control linkage of claim 1 wherein: said cam has a generally arrowhead shape, said dual driving surfaces comprising the leading edges of said arrowhead shape.
Claim 4
Dependent Claim
175 words
A linkage comprising an arrowhead cam pivoted at a first point and a follower member pivoted at a second point, said arRowhead cam comprising an arrowhead shaped portion having a first cam surface and a second cam surface, said follower member comprising first and second follower means cooperable with said first and second cam surfaces respectively, the spacing of said first and second pivot points and of said first and second follower means being such that rotation of said arrowhead cam in a first direction causes one of said surfaces to cooperate with its respective follower means while said second surface is inoperative to move its follower means, whereby said follower member moves in response to motion of said cam in said first direction, and rotation of said arrowhead cam in a second direction causes the other of said surfaces to cooperate with its respective follower means while said first surface is inoperative to move its follower means, and whereby said follower member moves in response to motion of said cam in said second direction.
Claim 5
Dependent Claim
175 words
A linkage comprising an arrowhead cam pivoted at a first point and a follower member pivoted at a second point, said arRowhead cam comprising an arrowhead shaped portion having a first cam surface and a second cam surface, said follower member comprising first and second follower means cooperable with said first and second cam surfaces respectively, the spacing of said first and second pivot points and of said first and second follower means being such that rotation of said arrowhead cam in a first direction causes one of said surfaces to cooperate with its respective follower means while said second surface is inoperative to move its follower means, whereby said follower member moves in response to motion of said cam in said first direction, and rotation of said arrowhead cam in a second direction causes the other of said surfaces to cooperate with its respective follower means while said first surface is inoperative to move its follower means, and whereby said follower member moves in response to motion of said cam in said second direction.
Claim 6
Dependent Claim
15 words
The combination of claim 3, and control motion input means connected to said arrowhead cam.
Claim 7
Dependent Claim
18 words
The combination of claim 4, said control motion input means comprising a link pivoted to said arrowhead cam.
Claim 8
Dependent Claim
14 words
The combination of claim 3, and output motion means connected to said follower member.
Claim 9
Dependent Claim
56 words
The combination of claim 6, said output motion means comprising a feedback loop of a servo having an actuator rod and a control valve rod, said feedback loop comprising a walking beam interconnecting the actuator rod and the control valve rod of said servo, and link means pivotably connecting said output motion means to said follower.
Claim 10
Dependent Claim
18 words
The combination of claim 3, each of said follower means comprising a roller pivoted on said follower member.
Claim 11
Dependent Claim
13 words
The combination of claim 7, and feel simulator means cooperable with said linkage.
Claim 12
Dependent Claim
64 words
The combination of claim 9, and an indented detent means in said follower, said feel simulator means comprising a spring-loaded roller which is urged into contact with said detent means, whereby an increasing feedback simulated feel force is provided at said input portion of said arrowhead cam in response to increasing motion of said arrowhead cam away from a neutral position of said linkage.
Claim 13
Dependent Claim
89 words
The combination of claim 10, said simulator means of said follower member comprising a pair of elongated lobes extending one to each side of a neutral position defined by said detent in said follower member, said spring-loaded roller is normally nested in said detent to further define said neutral position, and said lobes, including cam surfaces shaped for cooperation with said spring-loaded roller as said follower member moves to either side of the neutral position, whereby the shape of said lobe cam surfaces determines the feedback simulated feel force.
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) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |