Patent US3938407A successfully refreshed from Google Patents.
US3938407A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable ratio parking brake control
Assignee: Ford Motor Co
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Filing: 1974-08-28
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Granted: 1976-02-17
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Expires: 1994-08-28
Abstract
Abstract According to the present disclosure a variable ratio parking brake control has a foot operated lever with a cam slot. A guide member is pivotally connected to the lever and it also has a cam slot. A clevis that is connected to a parking brake cable has a bearing pin which is slidably supported within the cam slots of the lever and the guide member. A spring is supported by the guide member and exerts a spring force urging the clevis to the outer ends of the two cam slots. The clevis is slidable from the outer ends of the cam slots to the inner ends of the slots in response to both displacement of the lever from a brake released position to a brake applied position and a load on the clevis that exceeds an amount determined by the force of the spring. The displacement of the clevis from the outer end of the cam slot of the lever to the inner end of the slot increases the mechanical advantage ratio of the brake control system. The increase in ratio occurs in response to displacement of the lever and the tension in the brake cable.
Inventors
- 👤 Kenneth J. Nisbet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:02
CPC Classifications
B; B60; B60T; B60T11/00; B60T11/04; B60T11/08; B60T7/00; B60T7/02; B60T7/04; B60T7/045; G; G05; G05G; G05G7/00; G05G7/02; G05G7/04; Y; Y10; Y10T; Y10T74/00; Y10T74/20; Y10T74/20558; Y10T74/2057
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
145 words
A variable ratio brake control for a vehicle brake; said control including a pivotally supported manually operated lever having a cam surface; said lever being angularly displaceable from a brake released position to a brake applied position; said cam surface having an outer end remote from the pivot axis of said lever and an inner end closer to said pivot axis than said outer end; a force transmitting device slidably engaging said cam surface and constructed to be coupled to a wheel brake; a spring means engaging said device and urging said device to said outer end of said cam surface; said device being displaced from said outer end to said inner end in response to displacement of said lever from said brake released position to said brake applied position and a brake applying load on said force transmitting device that exceeds a predetermined amount.
Claim 2
Dependent Claim
145 words
A variable ratio brake control for a vehicle brake; said control including a pivotally supported manually operated lever having a cam surface; said lever being angularly displaceable from a brake released position to a brake applied position; said cam surface having an outer end remote from the pivot axis of said lever and an inner end closer to said pivot axis than said outer end; a force transmitting device slidably engaging said cam surface and constructed to be coupled to a wheel brake; a spring means engaging said device and urging said device to said outer end of said cam surface; said device being displaced from said outer end to said inner end in response to displacement of said lever from said brake released position to said brake applied position and a brake applying load on said force transmitting device that exceeds a predetermined amount.
Claim 3
Dependent Claim
284 words
A variable ratio brake control for a cable actuated vehicle brake; said control including a housing, a manually operated lever and pivot means connecting said lever to said housing; said lever being angularly displaceable from a brake released position to a brake applied position; said lever having a cam slot with an outer end remote from the pivot axis of said pivot means and an inner end closer to said pivot axis than said outer end; a guide member pivotally connected to said housing by said pivot means and angularly displaceable relative to said lever; said guide member having a cam slot with an outer end remote from said pivot axis and an inner end closer to said pivot axis than said just mentioned outer end; said cam slot of said member overlapping said cam slot of said lever and cooperating therewith to define an opening of a size less than the size of said lever cam slot or said member cam slot; a force transmitting device disposed in said opening and slidably supported in said cam slot of said lever and said cam slot of said member; said device being constructed to be coupled to a brake cable; spring means supported by said member exerting a spring force urging said device toward said outer end of said member cam slot and said outer end of said lever cam slot; said device being slidable from said outer end of said lever cam slot to said inner end of said lever cam slot in response to displacement of said lever from said brake released position to said brake applied position and a brake applying load on said force transmitting device that exceeds a predetermined amount.
Claim 4
Dependent Claim
284 words
A variable ratio brake control for a cable actuated vehicle brake; said control including a housing, a manually operated lever and pivot means connecting said lever to said housing; said lever being angularly displaceable from a brake released position to a brake applied position; said lever having a cam slot with an outer end remote from the pivot axis of said pivot means and an inner end closer to said pivot axis than said outer end; a guide member pivotally connected to said housing by said pivot means and angularly displaceable relative to said lever; said guide member having a cam slot with an outer end remote from said pivot axis and an inner end closer to said pivot axis than said just mentioned outer end; said cam slot of said member overlapping said cam slot of said lever and cooperating therewith to define an opening of a size less than the size of said lever cam slot or said member cam slot; a force transmitting device disposed in said opening and slidably supported in said cam slot of said lever and said cam slot of said member; said device being constructed to be coupled to a brake cable; spring means supported by said member exerting a spring force urging said device toward said outer end of said member cam slot and said outer end of said lever cam slot; said device being slidable from said outer end of said lever cam slot to said inner end of said lever cam slot in response to displacement of said lever from said brake released position to said brake applied position and a brake applying load on said force transmitting device that exceeds a predetermined amount.
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) | 1979-02-16 | 1979-08-18 | 1980-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-16 | 1983-08-18 | 1984-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-16 | 1987-08-18 | 1988-02-17 | $7700.00 | Window Closed / Lapsed |