US4097840A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic semi-trailer landing gear extension and retraction apparatus
Assignee: Individual
•
Filing: 1976-10-18
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Granted: 1978-06-27
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Expires: 1996-10-18
Abstract
Abstract An improved apparatus for automatically extending and retracting the landing gear of a semi-trailer. The apparatus includes a reversible electric motor and speed reducer removably drivingly securable to an existing manually operated mechanism for extending and retracting a landing gear. Electric circuitry is provided for permitting an operator to control the extension and retraction of the landing gear from within the cab of a tractor and, alternately, from the exterior of the semi-trailer. The electrical circuitry provides both audible and visual indication of the position status of the landing gear and automatic cutoff of the electric motor when the landing gear is fully extended, and alternately, when the landing gear is fully retracted.
Inventors
- 👤 Warner A. Chappelle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:13
CPC Classifications
B; B60; B60S; B60S9/00; B60S9/02; B60S9/04
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
328 words
In a tractor trailer rig of the type which includes a conventional tractor having an operator's cab, a source of electrical power, and a fifth wheel hitch member; a semi-trailer having hitch pin means on the forward end portion for engaging the fifth wheel hitch member, road wheels journaled on the rear end portion and an alternately extendable and retractable landing gear mounted intermediate the hitch pin means and the road wheels; the landing gear having gear drive means operatively engaged therewith which gear drive means includes an input drive shaft adapted to be engaged by a crank handle for manual rotation thereof in a first direction to extend the landing gear to engage the ground and support the semi-trailer independently of the tractor and, alternately, in a second direction to retract the landing gear from the ground engaging position to allow the forward end portion of the semi-trailer to be supported by the tractor with the hitch pin means engaging the fifth wheel hitch member; an improved automatic landing gear extension and retraction apparatus comprising: an electric drive motor mounted on the forward end portion of the semi-trailer and having a power output shaft; means for drivingly connecting the power output shaft to the input drive shaft of the gear drive means of the landing gear; position sensing means operatively connected to the landing gear for providing a first signal output when the landing gear is retracted and, alternately, for providing a second signal output when the landing gear is extended; and control circuit means mutually interconnecting the source of electrical power, the electric drive motor and the position sensing means, and responsive to external control thereof, for providing electrical power to the electric drive motor to rotate the input drive shaft in the first direction to extend the landing gear and, alternately, for providing electrical power to the electric drive motor to rotate the input drive shaft in the second direction to retract the landing gear.
Claim 2
Dependent Claim
328 words
In a tractor trailer rig of the type which includes a conventional tractor having an operator's cab, a source of electrical power, and a fifth wheel hitch member; a semi-trailer having hitch pin means on the forward end portion for engaging the fifth wheel hitch member, road wheels journaled on the rear end portion and an alternately extendable and retractable landing gear mounted intermediate the hitch pin means and the road wheels; the landing gear having gear drive means operatively engaged therewith which gear drive means includes an input drive shaft adapted to be engaged by a crank handle for manual rotation thereof in a first direction to extend the landing gear to engage the ground and support the semi-trailer independently of the tractor and, alternately, in a second direction to retract the landing gear from the ground engaging position to allow the forward end portion of the semi-trailer to be supported by the tractor with the hitch pin means engaging the fifth wheel hitch member; an improved automatic landing gear extension and retraction apparatus comprising: an electric drive motor mounted on the forward end portion of the semi-trailer and having a power output shaft; means for drivingly connecting the power output shaft to the input drive shaft of the gear drive means of the landing gear; position sensing means operatively connected to the landing gear for providing a first signal output when the landing gear is retracted and, alternately, for providing a second signal output when the landing gear is extended; and control circuit means mutually interconnecting the source of electrical power, the electric drive motor and the position sensing means, and responsive to external control thereof, for providing electrical power to the electric drive motor to rotate the input drive shaft in the first direction to extend the landing gear and, alternately, for providing electrical power to the electric drive motor to rotate the input drive shaft in the second direction to retract the landing gear.
Claim 3
Dependent Claim
69 words
The apparatus as defined in claim 1 wherein said control circuit means is characterized further to include: switch means for providing, in a first position thereof, electrical power to the electric drive motor to rotate the input drive shaft in the first direction and, alternately, for providing, in a second position thereof, electrical power to the electric drive motor to rotate the input drive shaft in the second direction.
Claim 4
Dependent Claim
16 words
The apparatus as defined in claim 2 wherein said switch means is mounted on said semi-trailer.
Claim 5
Dependent Claim
64 words
The apparatus as defined in claim 2 wherein said switch means is characterized further to include: a first switch mounted on said semi-trailer; a second switch mounted on said tractor; and said first and second switches being electrically interconnected and arranged so as to permit the electrical power provided to the electric drive motor to be switched at the semi-trailer, and at the tractor.
Claim 6
Dependent Claim
45 words
The apparatus as defined in claim 1 wherein said control circuit means is characterized further to include: a first control circuit mounted on the semi-trailer; a second control circuit mounted on the tractor; and electrical conduit means for interconnecting the first and second control circuits.
Claim 7
Dependent Claim
169 words
The apparatus as defined in claim 5 wherein said first control circuit is characterized further to include: first switch means having an input terminal and an output terminal for alternately electrically connecting and disconnecting the input and output terminals thereof in response to external manipulation thereof; means conneced to the input terminal of said first switch means for connecting said input terminal to the source of electrical power via said electrical conduit means; relay means interconnecting the output terminal of said first switch means and the electric drive motor for providing electrical power therethrough to the electric drive motor to alternately rotate the input drive shaft in the first direction and in the second direction in response to manipulation of said first switch means; and position sensing means responsive to the extension and retraction of the landing gear and connected to said relay means for providing a first signal output when the landing gear is fully retracted and a second signal output when the landing gear is fully extended.
Claim 8
Dependent Claim
55 words
The apparatus as defined in claim 6 wherein said second control circuit is characterized further to include: first indicator means connected via said electrical conduit means to said position sensing means for providing a visual indication in response to the first signal output of said position sensing means when the landing gear is fully retracted.
Claim 9
Dependent Claim
55 words
The apparatus as defined in claim 7 wherein said second control circuit is characterized further to include: second indicator means connected via said electrical conduit means to said position sensing means for providing a visual indication in response to the second signal output from said position sensing means when the landing gear is fully extended.
Claim 10
Dependent Claim
106 words
The apparatus as defined in claim 8 wherein said position sensing means is characterized further as being constructed and arranged for providing a third signal output when the landing gear is in a position other than the fully retracted position and the fully extended position; and wherein said second control circuit is characterized further to include: third indicator means connected via said electrical conduit means to said position sensing means for providing an audible indication in response to the third signal output from said position sensing means when the landing gear is in a position other than the fully retracted position or the fully extended position.
Claim 11
Dependent Claim
49 words
The apparatus as defined in claim 9 wherein said second control circuit is characterized further to include: fourth indicator means connected via said electrical conduit means to said relay means for providing a visual indication when electrical power is applied through said relay means to the electric drive motor.
Claim 12
Dependent Claim
186 words
The apparatus as defined in claim 10 wherein said second control circuit is characterized further to include: second switch means, having an input terminal and an output terminal, for alternately electrically connecting and disconnecting the input and output terminals thereof in response to external manipulation thereof; and means connected to the input terminal of said second switch means for connecting the input terminal thereof to the source of electrical power; and said first control circuit is characterized further to include: third switch means, having first and second input terminals and an output terminal, interposed between said relay means and the output terminal of said first switch means, the first input terminal of said third switch means being electrically connected to the output terminal of said first switch means, the output terminal of said third switch means being electrically connected to said relay means, and the second input terminal of said switch means being electrically connected via said electrical conduit means to the output terminal of said second switch means, for connecting said relay means to said first switch means and, alternately, to said second switch means.
Claim 13
Dependent Claim
24 words
The apparatus as defined in claim 11 wherein said second control circuit is characterized further as being located within the cab of the tractor.
Claim 14
Dependent Claim
62 words
The apparatus as defined in claim 11 wherein said first control circuit is characterized further to include: container means mounted on said semi-trailer for housing said first and third switch means; and door means on said container means for alternately opening and closing said container means to provide and prevent access to said first and third switch means in said container means.
Claim 15
Dependent Claim
41 words
The apparatus as defined in claim 13 wherein said control circuit is characterized further to include: lock means operatively engageable between said door means and said container means for selectively locking said door means in a position closing said container means.
Claim 16
Dependent Claim
74 words
The apparatus as defined in claim 14 wherein said means for drivingly connecting the power output shaft of the electric drive motor to the input drive shaft of the gear drive means of the landing gear is characterized further to include: speed reducer means for rotating the input drive shaft of the gear drive means at a rotational speed less than the rotational speed of the power output shaft of the electric drive motor.
Claim 17
Dependent Claim
22 words
The apparatus as defined in claim 15 wherein the electric drive motor is characterized further as being a reversible, direct current motor.
Claim 18
Dependent Claim
32 words
The apparatus as defined in claim 15 wherein the electric drive motor is characterized further as being a reversible, fractional horsepower, direct current motor having a power rating of approximately one-twentieth horsepower.
Claim 19
Dependent Claim
41 words
The apparatus as defined in claim 1 wherein said control circuit means is characterized further to include: means responsive to said position sensing means for substantially shutting off electrical power to the electric drive motor when the landing gear is extended.
Claim 20
Dependent Claim
40 words
The apparatus as defined in claim 1 wherein said control circuit means is characterized further to include: means responsive to said position sensing means substantially shutting off electrical power to the electric drive motor when the landing gear is retracted.
Claim 21
Dependent Claim
76 words
The apparatus as defined in claim 1 wherein said control circuit means is characterized further to include: means responsive to the first signal output of said position sensing means for automatically shutting off electrical power to the electric drive motor when the landing gear is retracted; and means responsive to the second signal output of said position sensing means for automatically shutting off electrical power to the electric drive motor when the landing gear is extended.
Claim 22
Dependent Claim
268 words
An improved automatic landing gear extension and retraction apparatus for use with a tractor having an operator's cab and a source of electrical power, and with a semi-trailer having hitch means on the forward end portion and road wheels journaled on the rear end portion thereof, comprising: an alternately extendable and retractable landing gear mounted on the forward end portion of the semi-trailer intermediate the hitch means and the road wheels; a gear drive mechanism operatively engaged with said landing gear and having an input drive shaft constructed and arranged such that rotation thereof in a first direction causes a corresponding extension of the landing gear and, alternately, rotation thereof in a second direction causes retraction of the landing gear; an electric drive motor mounted on the forward end portion of the semi-trailer and having a power output shaft; means for drivingly connecting the power output shaft to the input drive shaft of said gear drive mechanism; position sensing means operatively connected to said landing gear for providing a first signal output when said landing gear is retracted, and alternately, for providing a second signal output when said landing gear is extended; and control circuit means mutually interconnecting the source of electrical power, said electric drive motor and said position sensing means, and responsive to external control thereof, for providing electrical power to said electric drive motor to rotate the input drive shaft in the first direction to extend said landing gear and, alternately, for providing electrical power to said electric drive motor to rotate the input drive shaft in the second direction to retract said landing gear.
Claim 23
Dependent Claim
268 words
An improved automatic landing gear extension and retraction apparatus for use with a tractor having an operator's cab and a source of electrical power, and with a semi-trailer having hitch means on the forward end portion and road wheels journaled on the rear end portion thereof, comprising: an alternately extendable and retractable landing gear mounted on the forward end portion of the semi-trailer intermediate the hitch means and the road wheels; a gear drive mechanism operatively engaged with said landing gear and having an input drive shaft constructed and arranged such that rotation thereof in a first direction causes a corresponding extension of the landing gear and, alternately, rotation thereof in a second direction causes retraction of the landing gear; an electric drive motor mounted on the forward end portion of the semi-trailer and having a power output shaft; means for drivingly connecting the power output shaft to the input drive shaft of said gear drive mechanism; position sensing means operatively connected to said landing gear for providing a first signal output when said landing gear is retracted, and alternately, for providing a second signal output when said landing gear is extended; and control circuit means mutually interconnecting the source of electrical power, said electric drive motor and said position sensing means, and responsive to external control thereof, for providing electrical power to said electric drive motor to rotate the input drive shaft in the first direction to extend said landing gear and, alternately, for providing electrical power to said electric drive motor to rotate the input drive shaft in the second direction to retract said landing gear.
Claim 24
Dependent Claim
68 words
The apparatus as defined in claim 21 wherein said control circuitry is characterized further to include: switch means for providing, in a first position thereof, electrical power to said electric drive motor to rotate the input drive shaft in the first direction and, alternately, for providing, in a second position thereof, electrical power to said electric drive motor to rotate the input drive shaft in the second direction.
Claim 25
Dependent Claim
16 words
The apparatus as defined in claim 22 wherein said switch means is mounted on said semi-trailer.
Claim 26
Dependent Claim
60 words
The apparatus as defined in claim 22 wherein said switch means is characterized further to include: a first switch mounted on said semi-trailer; a second switch mounted on said tractor; and means electrically connecting said first and second switches for permitting the electrical power provided to said electric drive motor to be switched at the semi-trailer and at the tractor.
Claim 27
Dependent Claim
45 words
The apparatus as defined in claim 21 wherein said control circuit means is characterized further to include: a first control circuit mounted on the semi-trailer; a second control circuit mounted on the tractor; and electric conduit means for interconnecting the first and second control circuits.
Claim 28
Dependent Claim
42 words
The apparatus as defined in claim 21 wherein said control circuit means is characterized further to include: means responsive to said position sensing means for discontinuing the operation of said electric drive motor when said landing gear is in a predetermined position.
Claim 29
Dependent Claim
41 words
The apparatus as defined in claim 21 wherein said control circuit means is characterized further to include: means responsive to said position sensing means for substantially shutting off electrical power to said electric drive motor when said landing gear is extended.
Claim 30
Dependent Claim
41 words
The apparatus as defined in claim 21 wherein said control circuit means is characterized further to include: means responsive to said position sensing means for substantially shutting off electrical power to said electric drive motor when said landing gear is retracted.
Claim 31
Dependent Claim
73 words
The apparatus as defined in claim 21 wherein said control circuit means is characterized further to include: means responsive to the first signal output of said position sensing means for automatically discontinuing the operation of said electric motor when said landing gear is retracted; and means responsive to the second signal output of said position sensing means for automatically discontinuing the operation of said electric drive motor when said landing gear is extended.
References Cited (Backward Citations)
US3628811A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-26 | 1981-12-26 | 1982-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-26 | 1985-12-26 | 1986-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-26 | 1989-12-26 | 1990-06-27 | $7700.00 | Window Closed / Lapsed |