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US3734253A Expired / Lapsed US ⏱️ 0.0 years remaining

Overload applied no-back brakes

Assignee: Individual
•
Filing: 1971-02-17
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Granted: 1973-05-22
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Expires: 1991-02-17
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Abstract

Abstract A device intended for transmitting from a driving shaft to a driven member, in a bi-directional and non-reversible way, a limited torque, wherein said driven member, rotatably mounted on the driving shaft, is braked at rest by a bi-directional logarithmic brake, suppression means provide for suppressing the braking action upon rotation of the driving shaft, a torsion balance is provided for transmitting a torque under angular displacement from the driving shaft to the driven member, and reinstatement means reinstate said braking action when said angular displacement overcomes a pre-determined limit angle.

Inventors

  • 👤 P Derossi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 21:46
CPC Classifications
F; F16; F16D; F16D7/00; F16D7/02; F16D7/022; F16H; F16H35/00; F16H35/10

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 275 words
A device intended for transmitting from a driving shaft to a driven member, in a bi-directional and nonreversible way, a torque to be limited to a predetermined amount, comprising a driving shaft, a driven member rotatably mounted on said driving shaft, a bi-directional logarithmic brake connected to said driven member for braking said driven member in both directions of rotation, said logarithmic brake comprising a pair of fixed tubular shells mounted coaxially with said driving shaft on both sides of said driven member, and a pair of helical springs, said helical springs being both wound in the same direction, each helical spring being inserted with a small previous contraction load within one of said fixed tubular shells, the inner ends of said helical springs adjacent to said driven member being connected to said driven memBer, suppression means connected to said driving shaft and to said bi-directional logarithmic brake for suppressing the braking action of said bi-directional logarithmic brake upon rotation of the driving shaft, a torsion balance connected to said driving shaft and to said driven member for transmitting a torque from said driving shaft to said driven member and for producing an angular displacement between said driving shaft and said driven member depending upon the transmitted torque, and reinstatement means connected to said driving shaft and to said bi-directional logarithmic brake for reinstating said braking action upon angular displacement of said driving shaft with respect of said driven member overcoming a limit angle, said limit angle being chosen so as to correspond, according to the transmission characteristic of said torsion balance, to the maximum torque to which the transmitted torque is to be limited.
Claim 2
Independent Claim 275 words
A device intended for transmitting from a driving shaft to a driven member, in a bi-directional and nonreversible way, a torque to be limited to a predetermined amount, comprising a driving shaft, a driven member rotatably mounted on said driving shaft, a bi-directional logarithmic brake connected to said driven member for braking said driven member in both directions of rotation, said logarithmic brake comprising a pair of fixed tubular shells mounted coaxially with said driving shaft on both sides of said driven member, and a pair of helical springs, said helical springs being both wound in the same direction, each helical spring being inserted with a small previous contraction load within one of said fixed tubular shells, the inner ends of said helical springs adjacent to said driven member being connected to said driven memBer, suppression means connected to said driving shaft and to said bi-directional logarithmic brake for suppressing the braking action of said bi-directional logarithmic brake upon rotation of the driving shaft, a torsion balance connected to said driving shaft and to said driven member for transmitting a torque from said driving shaft to said driven member and for producing an angular displacement between said driving shaft and said driven member depending upon the transmitted torque, and reinstatement means connected to said driving shaft and to said bi-directional logarithmic brake for reinstating said braking action upon angular displacement of said driving shaft with respect of said driven member overcoming a limit angle, said limit angle being chosen so as to correspond, according to the transmission characteristic of said torsion balance, to the maximum torque to which the transmitted torque is to be limited.
Claim 3
Dependent Claim 82 words
A device as set forth in claim 1, wherein the outer ends of said helical springs, opposite said inner ends connected to said driven member, have engagement members, and said driving shaft carrier, in vicinity of said engagement members, engagement surfaces for co-operating with said engagement members in the winding directions of the respective helical springs, between said co-operating engagement members and engagement surfaces being provided at rest a small angular space, said engagement members and engagement surfaces forming said suppression means.
Claim 4
Dependent Claim 173 words
A device as set forth in claim 1, wherein the outer ends of said helical springs, opposite said inner ends connected to said driven member, have engagement members, and said driving shaft carries, in vicinity of said engagement members, engagement surfaces for co-operating with said engagement members in the winding directions of the respective helical springs, between said co-operating engagement members and engagement surfaces being provided at rest a small angular space, said engagement members and engagement surface forming said suppression means, said driving shaft further carrying, in vicinity of said engagement members, contact surfaces for co-operating with said engagement members in the unwinding directions of the respective helical springs, between said co-operating engagement members and contact surfaces being provided at rest a second angular space, said second angular space being greater than said small angular space provided between said engagement members and engagement surfaces, and said second angular space corresponding, according to the transmission characteristic of said torsion balance, to the maximum torque to which the transmitted torque is to be limited.
Claim 5
Dependent Claim 46 words
A device as set fort in claim 3, wherein said driving shaft is provided with sleeves carrying said engagement surfaces and contact surfaces, said driven member has a hub, and said torsion balance is connected to said hub and at at least one of said sleeves.
Claim 6
Dependent Claim 118 words
A device as set forth in claim 1, wherein said driving shaft has a grooved portion and carries at least a sleeve, said driven member has a hub, and wherein said torsion balance comprises a ring mounted on said grooved portion of the driving shaft for axial movement thereon without the possibility of rotating with respect to said driving shaft, a compression spring mounted on said driving shaft between said sleeve and said ring for pushing said ring towards said hub, and mutually contacting inclined surfaces provided on said hub and on said ring for turning the axial force applied by said compression spring into a torque applied to said hub and to the driven member connected therewith.
Claim 7
Dependent Claim 149 words
A device as set forth in claim 1, wherein said driving shaft has a grooved portion and carries at least a sleeve, said driven member has a hub, and wherein said torsion balance comprises a ring mounted on said grooved portion of the driving shaft for axial movement thereon without the possibility of rotating with respect to said driving shaft, a compression spring mounted on said driving shaft between said sleeve and said ring for pushing said ring toward said hub, and mutually contacting inclined surfaces provided on said hub and on said ring for turning the axial force applied by said compression spring into a torque applied to said hub and to the driven member connected therewith, each one of said inclined surfaces comprising a first portion and a second portion having an inclination greater than said first portion, for providing a non-linear characteristic of said torsion balance.
Claim 8
Dependent Claim 172 words
A device as set forth in claim 1, wherein said driving shaft has a grooved portion and carries at least a sleeve, said driven member has a hub, and wherein said torsion balance comprises a ring mounted on said grooved portion of the driving shaft for axial movement thereon without the possibility of rotating with respect to said driving shaft, a compression spring mounted on said driving shaft between said sleeve and said ring for pushing said ring towards said hub, an mutually contacting inclined surfaces provided on said hub and on said ring for turning the axial force applied by said compression spring into a torque applied to said hub and to the driven member connected therewith, said inclined surfaces having steps intended for mutually corresponding and releasing in engagement upon angular displacement of said driving shaft with respect of said driven member overcoming said limit angle, whereby the drive is then stopped and its return to transmission condition is avoided until to the driving shaft is imparted an opposite rotation.

References Cited (Backward Citations)

US2946417A Cited
US3034619A Cited
US3329242A Cited
US3367456A Cited
US3499511A Cited
US3596740A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-05-21 1976-11-20 1977-05-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-05-21 1980-11-20 1981-05-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-05-21 1984-11-20 1985-05-22 $7700.00 Window Closed / Lapsed

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