US4513831A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Weighing system
Assignee: Setra Systems LLC
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Filing: 1983-05-09
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Granted: 1985-04-30
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Expires: 2003-05-09
Abstract
Abstract A weighing system includes a weighing pan connected to a rigid armature by a mechanical filter constraining the armature to motion along a reference axis with respect to a housing and damping out transient forces along this axis resulting from the placement of objects on the pan. The mechanical filter includes spring and damping elements that provide a low-pass filter, that is, one that efficiently and quickly eliminates high frequency oscillations. In one form, the mechanical filter couples the pan to the armature. Because of this connection, friction in the mechanical filter does not result in frictional errors in the weighing measurement. In another form, a mechanical linkage couples the armature to the housing. A force transducer, comprising a pair of complementary opposed surfaces having a mutual separation which is related to the force across the transducer, is coupled between the armature and the housing. Coupled to the transducer is a position sensor which generates a signal representative of the separation between the complementary opposed surfaces of the transducer.
Inventors
- 👤 Shih-Ying Lee
- 👤 Dennis K. Briefer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:04
CPC Classifications
G; G01; G01G; G01G7/00; G01G7/06; G01G21/00; G01G21/24; G01G21/244; G01G23/00; G01G23/06
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
122 words
A weighing system comprising: A. force input member for supporting an object-to-be-weighed, B. a rigid armature member, C. first linkage including means for coupling said armature and a reference member whereby said armature is constrained to motion substantially parallel to a reference axis, said reference axis being fixed with respect to said reference member, D. mechanical means for coupling said force input member and said armature, E. force transducer coupled between said armature and said reference member, said force transducer including a pair of complementary opposed surfaces having a mutual separation which is related to the force across said transducer, and F. a position sensor for generating a signal representative of the separation between said complementary opposed surfaces of said force transducer.
Claim 2
Dependent Claim
122 words
A weighing system comprising: A. force input member for supporting an object-to-be-weighed, B. a rigid armature member, C. first linkage including means for coupling said armature and a reference member whereby said armature is constrained to motion substantially parallel to a reference axis, said reference axis being fixed with respect to said reference member, D. mechanical means for coupling said force input member and said armature, E. force transducer coupled between said armature and said reference member, said force transducer including a pair of complementary opposed surfaces having a mutual separation which is related to the force across said transducer, and F. a position sensor for generating a signal representative of the separation between said complementary opposed surfaces of said force transducer.
Claim 3
Dependent Claim
14 words
A system according to claim 1 wherein said mechanical coupling means comprises spring means.
Claim 4
Dependent Claim
16 words
A system according to claim 1 wherein said mechanical coupling means comprises a substantially rigid connection.
Claim 5
Dependent Claim
42 words
A system according to claim 1, wherein said mechanical coupling means comprises: A. spring means for resiliently coupling said force input member and said armature, and B. means for damping relative motion of said force input member with respect to said armature.
Claim 6
Dependent Claim
37 words
A system according to claim 4, wherein said spring means includes first spring means connected in parallel with said damping means and second spring means connected in series with said damping means to attenuate high frequency oscillations.
Claim 7
Independent Claim
34 words
A system according to claims 1 or 5 further comprising overforce protection means that limits the maximum displacement of said force input member in response to a force applied to said force input member.
Claim 8
Dependent Claim
38 words
A system according to claim 6, wherein said overforce protection means comprises a stop member that is fixed with respect to said reference member that limits said maximum displacement of said force input member along said weighing axis.
Claim 9
Dependent Claim
35 words
A system according to claim 4 wherein said spring means includes a second linkage means with means to constrain said force input member to motion substantially along a weighing axis parallel to said reference axis.
Claim 10
Independent Claim
86 words
A system according to claims 4 or 8 wherein said damper is a fluid damper and includes a pair of opposed elements having complementary opposing surfaces, one of said pair being coupled to said armature and the other of said pair being coupled to said force input member and being adapted for relative motion along said weighing axis, wherein said opposing surfaces include a plurality of alternating ridges and troughs, whereby fluid flow between said ridges and troughs resulting from said relative motion provides said damping.
Claim 11
Dependent Claim
229 words
A weighing system comprising: A. force input member for supporting an object-to-be-weighed, B. a rigid armature member, C. first linkage including means for coupling said armature and a reference member whereby said armature is constrained to motion substantially parallel to a reference axis, said reference axis being fixed with respect to said reference member, D. mechanical means for coupling said force input member and said armature, wherein said mechanical coupling means comprises: a support member mounted on said armature, means for damping relative motion of said force input member with respect to said armature, wherein said damping means is a fluid damper and includes a fluid chamber composed of opposing surfaces of said force input member and said support member, said fluid chamber being equipped with an orifice, whereby fluid flow into or out of said chamber through said orifice resulting from said relative motion provides said damping, and spring means for resiliently coupling said force input member and said armature, said spring means comprising a resilient member located between said opposing surfaces, E. force transducer coupled between said armature and said reference member, said force transducer including a pair of complementary opposed surfaces having a mutual separation which is related to the force across said transducer, and F. a position sensor for generating a signal representative of the separation between said complementary opposed surfaces of said force transducer.
Claim 12
Dependent Claim
229 words
A weighing system comprising: A. force input member for supporting an object-to-be-weighed, B. a rigid armature member, C. first linkage including means for coupling said armature and a reference member whereby said armature is constrained to motion substantially parallel to a reference axis, said reference axis being fixed with respect to said reference member, D. mechanical means for coupling said force input member and said armature, wherein said mechanical coupling means comprises: a support member mounted on said armature, means for damping relative motion of said force input member with respect to said armature, wherein said damping means is a fluid damper and includes a fluid chamber composed of opposing surfaces of said force input member and said support member, said fluid chamber being equipped with an orifice, whereby fluid flow into or out of said chamber through said orifice resulting from said relative motion provides said damping, and spring means for resiliently coupling said force input member and said armature, said spring means comprising a resilient member located between said opposing surfaces, E. force transducer coupled between said armature and said reference member, said force transducer including a pair of complementary opposed surfaces having a mutual separation which is related to the force across said transducer, and F. a position sensor for generating a signal representative of the separation between said complementary opposed surfaces of said force transducer.
Claim 13
Dependent Claim
34 words
A system according to claim 10 wherein said resilient member comprises a closed loop of resilient material spanning the gap between said force input member and said support member thereby defining said fluid chamber.
Claim 14
Dependent Claim
21 words
A system according to claim 10 wherein said resilient means comprises a plurality of resilient supports deployed between said opposing surfaces.
Claim 15
Dependent Claim
32 words
A system according to claim 1 wherein said first linear motion linkage includes an adjustable means for controlling the range of motion of said armature to be substantially along said reference axis.
Claim 16
Dependent Claim
57 words
A system according to claim 1 wherein said force transducer includes conductive elements on opposing portions of said opposed surfaces, and wherein said position sensor includes an electrical circuit coupled to said conductive elements, whereby said conductive elements and said circuit form an oscillator having a characteristic frequency related to said separation of said complementary opposed surfaces.
Claim 17
Dependent Claim
182 words
A weighing system comprising: A. force input member for supporting an object-to-be-weighed, B. a rigid armature member, C. first linkage including means for coupling said armature and a reference member whereby said armature is constrained to motion substantially parallel to a reference axis, said reference axis being fixed with respect to said reference member, D. mechanical means for coupling said force input member and said armature, wherein said mechanical coupling means comprises a parallelogram linkage including a first vertical member attached to said force input member, a second vertical member attached to said armature, a pair of resilient members secured between said vertical members in a generally parallel, spaced relationship, and means connected between said force input member and said armature for damping their relative motion, E. force transducer coupled between said armature and said reference member, said force transducer including a pair of complementary opposed surfaces having a mutual separation which is related to the force across said transducer, and F. a position sensor for generating a signal representative of the separation between said complementary opposed surfaces of said force transducer.
Claim 18
Dependent Claim
182 words
A weighing system comprising: A. force input member for supporting an object-to-be-weighed, B. a rigid armature member, C. first linkage including means for coupling said armature and a reference member whereby said armature is constrained to motion substantially parallel to a reference axis, said reference axis being fixed with respect to said reference member, D. mechanical means for coupling said force input member and said armature, wherein said mechanical coupling means comprises a parallelogram linkage including a first vertical member attached to said force input member, a second vertical member attached to said armature, a pair of resilient members secured between said vertical members in a generally parallel, spaced relationship, and means connected between said force input member and said armature for damping their relative motion, E. force transducer coupled between said armature and said reference member, said force transducer including a pair of complementary opposed surfaces having a mutual separation which is related to the force across said transducer, and F. a position sensor for generating a signal representative of the separation between said complementary opposed surfaces of said force transducer.
Claim 19
Dependent Claim
60 words
A system according to claim 15 wherein said damping means comprises a pair of arms each secured at one end to opposite sides of said parallelogram structure and extending towards one another in a generally parallel, mutually spaced relationship, and an energy absorbing material located between said arms so that said relative motion flexes said material to produce said damping.
Claim 20
Dependent Claim
15 words
A system according to claim 16 wherein said arms are formed of a resilient material.
Claim 21
Independent Claim
20 words
A system according to claims 16 or 17 wherein said arms extend generally along a diagonal of said parallelogram linkage.
Claim 22
Dependent Claim
24 words
A system according to claim 18 wherein said arms are each secured at one end to one of said first and second vertical members.
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) | 1988-04-29 | 1988-10-29 | 1989-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-29 | 1992-10-29 | 1993-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-29 | 1996-10-29 | 1997-04-30 | $7700.00 | Window Closed / Lapsed |