US3817007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aerial lift mechanism
Assignee: American LaFrance LLC
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Filing: 1971-10-04
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Granted: 1974-06-18
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Expires: 1991-10-04
Abstract
Abstract The aerial lift mechanism disclosed includes a telescopic boom arrangement, involving a plurality of rectangular tubular sections having therewithin hydraulic piston and cylinder means connected to operate such sections inwardly and outwardly, one of such sections being extendable and retractable at substantially greater rate than another, means being provided for controlling the movement of such sections, in the elevation of the boom, such means including circuitry in which suitable elements are employed to operate the parts in chosen sequence and simultaneously with certain of the elements including instrumentalities common to the respective systems.
Inventors
- 👤 T Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:58
CPC Classifications
B; B66; B66C; B66C23/00; B66C23/62; B66C23/64; B66C23/70; B66C23/701; B66F; B66F11/00; B66F11/04; B66F11/044; B66F11/046
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
288 words
In an aerial lift mechanism of the class described, in combination, a main vertical support and actuating unit comprising first hydraulic piston and cylinder means, a boom assembly connected to the unit for raising and lowering movement thereby, said assembly including an outer boom member, a middle boom member telescopically mounted with respect to the outer boom member, an inner boom member mounted for telescopic movement with respect to said outer and middle boom member, a second hydraulic piston and cylinder means mounted on said outer boom member and together therewith constituting an outer boom unit, said second hydraulic piston having a rod means, means directly interconnecting the middle boom member to said rod of said second piston for moving said middle boom member a distance equal to the distance of movement of the piston rod in both the extension direction and the retraction direction thereof and constituting with said middle boom member a middle boom unit, and cable and pulley means interconnecting said outer boom unit and said middle boom unit and said inner boom member to positively drive said inner boom member at a rate twice the rate of movement of the middle boom member responsive to either extension or retraction movement of said piston, said pulley means including a pair of spaced pulleys mounted on said middle boom unit, and said cable means being reeved around said pulley means and both ends deadended on the outer boom unit with an intermediate portion thereof between the pulleys connected to the inner boom member, whereby the inner boom is extended and retracted at substantially twice the rate of that of the middle boom unit with respect to the outer boom unit, and control means for such movement.
Claim 2
Dependent Claim
288 words
In an aerial lift mechanism of the class described, in combination, a main vertical support and actuating unit comprising first hydraulic piston and cylinder means, a boom assembly connected to the unit for raising and lowering movement thereby, said assembly including an outer boom member, a middle boom member telescopically mounted with respect to the outer boom member, an inner boom member mounted for telescopic movement with respect to said outer and middle boom member, a second hydraulic piston and cylinder means mounted on said outer boom member and together therewith constituting an outer boom unit, said second hydraulic piston having a rod means, means directly interconnecting the middle boom member to said rod of said second piston for moving said middle boom member a distance equal to the distance of movement of the piston rod in both the extension direction and the retraction direction thereof and constituting with said middle boom member a middle boom unit, and cable and pulley means interconnecting said outer boom unit and said middle boom unit and said inner boom member to positively drive said inner boom member at a rate twice the rate of movement of the middle boom member responsive to either extension or retraction movement of said piston, said pulley means including a pair of spaced pulleys mounted on said middle boom unit, and said cable means being reeved around said pulley means and both ends deadended on the outer boom unit with an intermediate portion thereof between the pulleys connected to the inner boom member, whereby the inner boom is extended and retracted at substantially twice the rate of that of the middle boom unit with respect to the outer boom unit, and control means for such movement.
Claim 3
Dependent Claim
32 words
The combination as claimed in claim 1, wherein the middle boom unit includes a channel assembly having a channel part therein, the hydraulic piston and cylinder means operate within the outline thereof.
Claim 4
Dependent Claim
135 words
The combination as claimed in claim 1, wherein the main boom member is a first rectangular tube connected to the support and actuating unit for pivotal raising and lowering movement thereby, the middle boom unit includes a second similar tube guidingly mounted within the first tube, the inner boom is a third tube similar to the second tube, and operably guided for reciprocation with respect to the first and second tubes, the means interconnecting the main boom unit and inner boom unit comprise a channel assembly mounted within the middle boom unit, and operable within the outline of the inner boom, a single hydraulic piston and cylinder means actuates said middle boom unit and inner boom, and the control means regulates the movement of the support and actuating unit, middle boom unit, and inner boom.
Claim 5
Dependent Claim
67 words
The combination as claimed in claim 1, wherein the control means comprises solenoid operated valves, a single pressure pump supplies fluid under pressure to the first and second hydraulic piston and cylinder means through said valves in accordance with the operation thereof, a solenoid operates said pressure pump, common instrumentalities actuate all of said solenoids, and include means to regulate such actuation in chosen sequence and simultaneously.
Claim 6
Dependent Claim
56 words
The combination as claimed in claim 4, wherein the means to regulate actuation include separatE contact parts, all said contact parts being arranged to operate the pressure pump solenoid through a common circuit, and diodes are positioned intermediate said parts and circuit to facilitate selective operation of said pump solenoid and thus the pump controlled thereby.
Claim 7
Dependent Claim
118 words
The combination as claimed in claim 4, wherein certain of the valves comprise a pair of four-way valves, one valve regulating operation of the first hydraulic piston and cylinder means for the vertical support and actuating unit, to raise and lower the boom assembly, the other valve regulating operation of the second hydraulic piston and cylinder means, to extend and retract the boom assembly member, unit and inner boom, the respective valves being actuated by the solenoids thereof to effect such movements, the pressure pump being simultaneously operated to in turn provide fluid under pressure as required, and the elctric circuits are arranged to effect the operation stated, and include means to prevent interfering actuation of the solenoids.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |