US4455977A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compression brake system
Assignee: Tecumseh Products Co
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Filing: 1981-08-31
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Granted: 1984-06-26
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Expires: 2001-08-31
Abstract
Abstract A safety device for an implement powered by a four-stroke cycle internal combustion engine having a deadman control for reducing the time required to stop the engine when the deadman control is released is disclosed and includes a switch operable upon release of the deadman control to disable the engine ignition system and an arrangement for opening an engine valve at a time other than its normal opening time in the engine cycle. In one preferred embodiment an engine exhaust valve is opened about maximum at 25 degrees prior to top deadcenter position of the engine piston during its compression stroke.
Inventors
- 👤 Steven R. Kuczenski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:19
CPC Classifications
F; F01; F01L; F01L13/00; F01L13/06; F02; F02B; F02B63/00; F02B63/02; F02B75/00; F02B75/02; F02B2075/022; F02B2075/027
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
135 words
A safety device for an implement powered by an internal combustion engine and having a deadman control normally biased toward a first position and actuable by a person operating the implement to a second position for reducing the time for the engine to come to a stop when the deadman control is released, the engine including inlet and exhaust valves and means for opening said valves at predetermined times in each normal operating cycle of the engine, the safety device comprising: an engine ignition impeding switch operable upon release of the deadman control to disable the engine ignition system, and means operable upon release of the deadman control during continued rotation of the engine for opening one of said engine valves at a time other than its normal opening time in the normal engine cycle.
Claim 2
Dependent Claim
135 words
A safety device for an implement powered by an internal combustion engine and having a deadman control normally biased toward a first position and actuable by a person operating the implement to a second position for reducing the time for the engine to come to a stop when the deadman control is released, the engine including inlet and exhaust valves and means for opening said valves at predetermined times in each normal operating cycle of the engine, the safety device comprising: an engine ignition impeding switch operable upon release of the deadman control to disable the engine ignition system, and means operable upon release of the deadman control during continued rotation of the engine for opening one of said engine valves at a time other than its normal opening time in the normal engine cycle.
Claim 3
Dependent Claim
16 words
The safety device of claim 1 wherein an engine exhaust one valve is the valve opened.
Claim 4
Dependent Claim
38 words
The safety device of claim 2 wherein the engine exhaust valve is opened at about the time in the engine cycle when ignition would normally occur thereby venting compressed fuel air mixture from the engine cylinder without combustion.
Claim 5
Dependent Claim
61 words
The safety device of claim 1 wherein the means for opening comprises an actuating rod axially movable within an engine camshaft, and a plunger movable in a radial direction under the control of the actuating rod between a retracted position where normal valve operation is unaffected and an extended position to periodically engage an engine valve lifter opening said one valve.
Claim 6
Dependent Claim
25 words
The safety device of claim 4 wherein the plunger is axially aligned with and angularly spaced from an actuating cam lobe for said one valve.
Claim 7
Dependent Claim
19 words
The safety device of claim 4 further comprising first spring means for biasing the plunger toward the retracted position.
Claim 8
Dependent Claim
21 words
The safety device of claim 4 wherein the actuating ring rod includes a tapered surface for engaging and moving the plunger.
Claim 9
Dependent Claim
41 words
The safety device of claim 5 further comprising first spring means for biasing the plunger toward the retracted position and second spring means for biasing the actuating rod toward a position to allow the first spring means to retract the plunger.
Claim 10
Dependent Claim
33 words
The safety device of claim 8 wherein an engine exhaust valve is opened by the means for opening at about 25 degrees before the associated piston reaches top deadcenter of its compression stroke.
Claim 11
Dependent Claim
65 words
The safety device of claim 4 wherein the means for opening further includes a lever pivotably attached near one end thereof to the engine and having the other end connected to the deadman control for pivotal movement between first and second positions in unison with movement of the deadman control between its corresponding first and second positions, the lever engaging and controlling the actuating rod.
Claim 12
Dependent Claim
46 words
The safety device of claim 10 wherein the lever pivots about an axis generally parallel to the actuating rod axis and includes an arm having a sloping surface for engaging and moving the actuating rod in its axial direction when the lever pivots about its axis.
Claim 13
Dependent Claim
33 words
The safety device of claim 11 further comprising a spring connected between the lever other end and the engine for urging the lever to pivot about its axis toward the first position thereof.
Claim 14
Dependent Claim
21 words
The safety device of claim 12 wherein the spring is the sole means biasing the deadman lever toward its first position.
Claim 15
Dependent Claim
43 words
The safety device of claim 10 wherein the ignition impeding switch comprises a normally open switch connected in parallel with an engine spark plug and actuable by movement of the lever to the first position thereof to short circuit the engine ignition system.
Claim 16
Dependent Claim
135 words
In an implement powered by an internal combustion engine and having a deadman control normally biased toward a first position and actuable by a person operating the implement to a second position, the engine including inlet and exhaust valves and a mechanism for opening the valves at predetermined times in each normal operating cycle of the engine, a method for reducing the time for the engine to come to a stop when the deadman control is released comprising: causing an engine ignition impeding switch to be operated upon release of the deadman control to disable the engine ignition system, and, further in response to release of the deadman control, opening one of the engine valves during continued rotation of the engine at a time other than its normal opening time in the normal engine cycle.
Claim 17
Dependent Claim
135 words
In an implement powered by an internal combustion engine and having a deadman control normally biased toward a first position and actuable by a person operating the implement to a second position, the engine including inlet and exhaust valves and a mechanism for opening the valves at predetermined times in each normal operating cycle of the engine, a method for reducing the time for the engine to come to a stop when the deadman control is released comprising: causing an engine ignition impeding switch to be operated upon release of the deadman control to disable the engine ignition system, and, further in response to release of the deadman control, opening one of the engine valves during continued rotation of the engine at a time other than its normal opening time in the normal engine cycle.
Claim 18
Dependent Claim
38 words
The method of claim 15 wherein the engine exhaust valve is opened to its maximum in response to release of the deadman control at about 25° prior to top deadcenter in the compression stroke of the engine cycle.
References Cited (Backward Citations)
US862448A
Cited
US2178152A
Cited
US2778349A
Cited
US3144009A
Cited
US3381676A
Cited
US3523465A
Cited
US3638632A
Cited
US3707952A
Cited
US3849620A
Cited
US3897768A
Cited
US3981289A
Cited
US4204384A
Cited
US4079721A
Cited
US4194485A
Cited
US4236494A
Cited
US4338893A
Cited
US4378765A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-26 | 1987-12-26 | 1988-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-26 | 1991-12-26 | 1992-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-26 | 1995-12-26 | 1996-06-26 | $7700.00 | Window Closed / Lapsed |