← Back to Patent Explorer
US4848757A Expired / Lapsed US ⏱️ 0.0 years remaining

Remote center compliance device with fully or partially coil-bound springs

Assignee: Charles Stark Draper Laboratory Inc
•
Filing: 1988-01-25
•
Granted: 1989-07-18
•
Expires: 2008-01-25
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An improved remote center compliance (RCC) device having translational and rotational compliance. The RCC device includes at least two spaced monolithic members having a common axis extending therethrough. Adjacent pairs of monolithic members are interconnected by a stage including at least three discrete coil springs spaced about the axis of the monolithic members. Each spring is axially extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance. The improvement includes providing coil springs that are at least partially coil-bound to increase the ratio of axzial stiffness to lateral stiffness of the springs and increase the projection of the center of compliance away from the RCC device.

Inventors

  • 👤 Thomas L. De Fazio

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 22:16
CPC Classifications
F; F16; F16F; F16F15/00; F16F15/02; B; B25; B25J; B25J17/00; B25J17/02; B25J17/0208; F16F15/04; F16F15/06; F16F15/067

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 127 words
In an improved center compliance (RCC) device having translational and rotational compliance, said RCC including at least two spaced monolithic members having a common axis extending therethrough, each adjacent pair of said monolithic members interconnected by a stage including at least three discrete coil springs spaced about the axis of said monolithic members, each said spring being axially extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs in said stage being substantially coil-bound to make their axial stiffness greater than their lateral stiffness, and also being axially disposed at an angle of less than 40 degrees to the axis of said monolithic members to project said center of compliance away from said RCC device.
Claim 2
Dependent Claim 127 words
In an improved center compliance (RCC) device having translational and rotational compliance, said RCC including at least two spaced monolithic members having a common axis extending therethrough, each adjacent pair of said monolithic members interconnected by a stage including at least three discrete coil springs spaced about the axis of said monolithic members, each said spring being axially extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs in said stage being substantially coil-bound to make their axial stiffness greater than their lateral stiffness, and also being axially disposed at an angle of less than 40 degrees to the axis of said monolithic members to project said center of compliance away from said RCC device.
Claim 3
Dependent Claim 31 words
The improved RCC device of claim 1 in which each said spring is axially disposed along a generatrix of a cone whose vertex lies proximate the axis of said monolithic members.
Claim 4
Dependent Claim 23 words
The improved RCC device of claim 2 in which said RCC device includes two monolithic members and a single stage of coil springs.
Claim 5
Dependent Claim 25 words
The improved RCC device of claim 1 in which the ratio of axial stiffness to lateral stiffness of said springs is between 1 and 100.
Claim 6
Dependent Claim 20 words
The improved RCC device of claim 4 in which the ratio of axial stiffness to lateral stiffness is approximately 30.
Claim 7
Dependent Claim 14 words
The improved RCC device of claim 1 in which said springs are axially compressible.
Claim 8
Dependent Claim 18 words
The improved RCC device of claim 1 in which said springs are all wound in the same direction.
Claim 9
Dependent Claim 29 words
The improved RCC device of claim 1 in which at least one of said springs is wound in an oppositely directed helical path than the rest of said springs.
Claim 10
Dependent Claim 13 words
The improved RCC device of claim 1 in which said springs are preloaded.
Claim 11
Dependent Claim 15 words
The improved RCC device of claim 1 in which all of said springs are identical.
Claim 12
Dependent Claim 21 words
The improved RCC device of claim 1 in which said springs are equally spaced about the axis of said monolithic members.
Claim 13
Dependent Claim 21 words
The improved RCC device of claim 1 in which said center of compliance falls on the axis of said monolithic members.
Claim 14
Dependent Claim 39 words
The improved RCC device of claim 1 further including a support structure spaced from said RCC device and interconnected to said RCC device by at least one axially compressible discrete element for providing axial compliance to said RCC device.
Claim 15
Dependent Claim 18 words
The improved RCC device of claim 13 in which said axially compressible discrete element is a coil spring.
Claim 16
Dependent Claim 15 words
The improved RCC device of claim 14 in which said coil spring is partially coil-bound.
Claim 17
Dependent Claim 27 words
The improved RCC device of claim 13 in which said axially compressible discrete element is a shear pad of alternating stiff material and less stiff elastomeric laminations.
Claim 18
Dependent Claim 14 words
The improved RCC device of claim 13 in which said element is axially extensible.
Claim 19
Dependent Claim 13 words
The improved RCC device of claim 13 in which said springs are preloaded.
Claim 20
Dependent Claim 22 words
The improved RCC device of claim 13 further including means for preventing cocking rotation between said RCC device and said support structure.
Claim 21
Dependent Claim 36 words
The improved RCC device of claim 19 in which said means for preventing cocking rotation includes at least one pin attached to said support structure, each said pin engaging a complementary hole in said RCC device.
Claim 22
Dependent Claim 126 words
In an improved remote center compliance (RCC) device having translational and rotational compliance, said RCC including two spaced monolithic members having a common axis extending therethrough interconnected by at least three discrete coil springs spaced about said axis, said springs being axially disposed along generatrices of a cone and being axially compressible and extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs being substantially but not fully coil-bound to make the ratio of axial stiffness to lateral stiffness greater than one, the axis of each said spring forming an angle of less than 40 degrees with the axis of said monolithic members to project said center of compliance away from said RCC device.
Claim 23
Dependent Claim 126 words
In an improved remote center compliance (RCC) device having translational and rotational compliance, said RCC including two spaced monolithic members having a common axis extending therethrough interconnected by at least three discrete coil springs spaced about said axis, said springs being axially disposed along generatrices of a cone and being axially compressible and extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs being substantially but not fully coil-bound to make the ratio of axial stiffness to lateral stiffness greater than one, the axis of each said spring forming an angle of less than 40 degrees with the axis of said monolithic members to project said center of compliance away from said RCC device.
Claim 24
Dependent Claim 25 words
The improved RCC device of claim 21 in which the ratio of axial stiffness to lateral stiffness of said springs is between 5 and 50.
Claim 25
Dependent Claim 13 words
The improved RCC device of claim 21 in which said springs are preloaded.
Claim 26
Dependent Claim 117 words
In an improved remote center compliance (RCC) device having translational and rotational compliance, said RCC including two spaced monolithic members having a common axis extending therethrough interconnected by at least three discrete coil springs spaced about said axis, said springs being axially disposed along generatrices of a cone and being axially extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs being substantially coil-bound to make their axial stiffness greater than their lateral stiffness and also being axially disposed at an angle of less than 40 degrees to the axis of said monolithic members to project said center of compliance away from said RCC device.
Claim 27
Dependent Claim 117 words
In an improved remote center compliance (RCC) device having translational and rotational compliance, said RCC including two spaced monolithic members having a common axis extending therethrough interconnected by at least three discrete coil springs spaced about said axis, said springs being axially disposed along generatrices of a cone and being axially extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs being substantially coil-bound to make their axial stiffness greater than their lateral stiffness and also being axially disposed at an angle of less than 40 degrees to the axis of said monolithic members to project said center of compliance away from said RCC device.
Claim 28
Dependent Claim 136 words
In an improved remote center compliance (RCC) device having translational and rotational compliance, said RCC including at least two spaced monolithic members having a common axis extending therethrough, each adjacent pair of said monolithic members interconnected by a stage including at least three discrete coil springs spaced about the axis of said monolithic members, each said spring being axially compressible and extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs in said stage being substantially but not fully coil-bound to make the ratio of axial stiffness to lateral stiffness greater than one, and also being axially disposed at an angle of less than 40 degrees to the axis of said monolithic members to project said center of compliance away from said RCC device.
Claim 29
Dependent Claim 136 words
In an improved remote center compliance (RCC) device having translational and rotational compliance, said RCC including at least two spaced monolithic members having a common axis extending therethrough, each adjacent pair of said monolithic members interconnected by a stage including at least three discrete coil springs spaced about the axis of said monolithic members, each said spring being axially compressible and extensible and laterally deformable for providing both rotational and translational compliance about a center of compliance, the improvement comprising: said coil springs in said stage being substantially but not fully coil-bound to make the ratio of axial stiffness to lateral stiffness greater than one, and also being axially disposed at an angle of less than 40 degrees to the axis of said monolithic members to project said center of compliance away from said RCC device.

References Cited (Backward Citations)

DE244311C Cited
US355197A Cited
US485652A Cited
CA607438A Cited
US2068269A Cited
GB501130A Cited
GB622346A Cited
US4379363A Cited
US4414750A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-07-17 1993-01-16 1993-07-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-07-17 1997-01-16 1997-07-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-07-17 2001-01-16 2001-07-18 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag