US3591016A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Boom extension means having more than three boom extension members for use with a truck crane
Assignee: Tadano Ltd
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Filing: 1967-07-19
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Granted: 1971-07-06
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Expires: 1987-07-19
Abstract
Abstract A boom construction comprises a tubular base member which is adapted to be mounted on a platform or a vehicle in a manner permitting it to be pivoted about a horizontal axis and to be swung about a vertical axis. Three separate additional boom members are telescoped within the base boom member and are movable relative to the base member and each other under the control of a plurality of fluid control cylinders which are mounted within the boom members. The first control cylinder is pivoted to the first inner one of the additional boom members preferably at the inner end thereof and it carries a piston having a piston rod which is pivoted at its inner end to the base boom member. A second fluid cylinder is pivoted to the second inner boom member and has a piston which is slidable therein with a piston rod which is pivoted at its inner end to a second boom member. Finally, a third inner boom member which is telescopic within the interior of all of the other boom member carries a third fluid cylinder having a third fluid piston slidable therein with a third connecting rod therefor which is connected at its inner end to the second innermost boom member. A feature of the construction is that the piston rods connected between the base member and the first boom member and the second boom member and the first boom member are provided with a double set of flow passages therethrough so that the fluid pressure which is directed into the first fluid cylinder on a pressure side thereof and which will cause expansion of the first boom member in respect to the base member will be directed through the other passage and into the pressure side of the second fluid cylinder to facilitate expansion of the second boom member in respect to the first boom member. The outermost fluid cylinder requires a piston rod with only one passage to complete the pressurization cycle for each of the fluid control cylinders and the expansion of all the boom members to an erected position simultaneously.
Inventors
- 👤 Masatoshi Hanada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:03
CPC Classifications
B; B66; B66C; B66C23/00; B66C23/62; B66C23/64; B66C23/70; B66C23/701; B66C23/705
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
1023 words
A boom construction comprising a truck chassis, a turning bed mounted on said truck chassis for rotation through a horizontal plaNe, an extendible-retractible boom pivotally connected on said turning bed, means for raising and lowering said boom in a vertical plane about is pivoted connection to said turning bed, said boom comprising a stationary tubular base boom member attached to said turning bed and said means for raising and lowering said boom being secured to said base boom member, a plurality of concentrically arranged tubular boom members being disposed within said base boom member and being displaceable between a fully retracted position at least partially within said base boom member and a fully extended position with said boom members projecting in a series arrangement outwardly from said base boom member for providing a selected length of said boom, said concentrically arranged boom members comprising at least a first boom member, a second boom member and a third boom member, in the fully retracted position said third boom member being positioned within said second boom member said second boom member being positioned within said first boom member and said first boom member being positioned within said base boom member, in the retracted position the inner ends of said first, second and third boom members closer to said turning bed being spaced outwardly from the end of said base boom member secured to said turning bed with the end of said second base member being spaced outwardly from the end of said first base member and the end of said third base member being spaced outwardly from the end of said second base member, a first hydraulic hoist is positioned between said base boom member and said second boom member and comprises an axially extending cylinder, a piston axially movable within said cylinder, and a piston rod secured to said piston and extending outwardly from said cylinder having an outer end spaced axially outwardly from said cylinder, the outer end of said piston rod being pin connected to said base boom member at a location between the inner end of said first boom member and the end of said base member secured to said turning bed and said cylinder connected at its inner end closer to said turning bed to the inner end of said first boom member, a second hydraulic hoist is positioned between said first boom member and said second boom member and comprises an axially extending cylinder a piston axially movable within said cylinder and a piston rod secured to said piston and extending axially therefrom outwardly from said cylinder toward said turning bed, said piston rod of said second hydraulic hoist being pin connected at its inner end to the inner end of said first boom member at approximately the same transverse location as the connection of said cylinder of said first hydraulic hoist to said first boom member and the inner end of said cylinder of said second hydraulic hoist being connected to the inner end of said second boom member, a third hydraulic hoist being positioned between said second and third boom members and comprising an axially extending cylinder, a piston axially movable within said cylinder, and a piston rod secured to said piston and extending outwardly from the outer end of said cylinder, said piston rod being secured at its inner end within said cylinder of said third hydraulic hoist to said piston therein and extending outwardly and being secured at its outer end to said third boom member at a point spaced intermediate the ends of said third boom member, said cylinder of said third hydraulic hoist being secured to said second boom member adjacent the inner end of said second boom member so that said first and second boom members are displaced outwardly into their extended positions by the action of said cylinders of said first and second hydraulic hoists riding outwardly on said piston rods and said third boom member is displaced outwardly by the action of said piston rod of said third hydraulic hoist being displaced outwardly from the cylinder of said third hydraulic hoist secured at its inner end to said second boom member, said piston rods of said first and seCond hydraulic hoists having a centrally arranged axially extending passageway and an annular axially extending passageway disposed concentrically about said central passageway, said piston in each of said cylinders of said first and second hydraulic hoists dividing the interior of said cylinder into a pair of variable volume chambers as said piston is moved between the extended and retracted positions, said centrally arranged passageway extending through said piston rod and said piston into the chamber located in the outer end of said cylinder and said annular passageway terminating in said piston rod before it reaches said piston and having an opening therefrom into the chamber on the opposite side of said piston from the other said chamber so that said annular passageway is connected to the chamber located in the cylinder closer to the turning bed, said chamber closer to said turning bed in said first and second hydraulic hoists having an opening extending through the end of said cylinders connected to said first and second boom members, respectively, the walls of said cylinders of said first and second hydraulic hoists providing a passageway extending for the length of said cylinder from the outer end thereof to the end of said cylinders located closer to said turning bed, and the inner end of said cylinder of said first hydraulic hoist being positioned adjacent the inner end of said piston rod of said second hydraulic hoist and the inner end of said cylinder of said second hydraulic hoist being positioned adjacent the inner end of the cylinder of said third hydraulic hoist so that the flow of hydraulic fluid for displacing said first, second and third boom members between the extended and retracted positions passes between the respective first, second and third hydraulic hoists without additional crossover connections and the interconnecting flow of hydraulic fluid between adjacent said hydraulic hoists are located at the inner ends of said cylinders of said hydraulic hoists.
Claim 2
Dependent Claim
1023 words
A boom construction comprising a truck chassis, a turning bed mounted on said truck chassis for rotation through a horizontal plaNe, an extendible-retractible boom pivotally connected on said turning bed, means for raising and lowering said boom in a vertical plane about is pivoted connection to said turning bed, said boom comprising a stationary tubular base boom member attached to said turning bed and said means for raising and lowering said boom being secured to said base boom member, a plurality of concentrically arranged tubular boom members being disposed within said base boom member and being displaceable between a fully retracted position at least partially within said base boom member and a fully extended position with said boom members projecting in a series arrangement outwardly from said base boom member for providing a selected length of said boom, said concentrically arranged boom members comprising at least a first boom member, a second boom member and a third boom member, in the fully retracted position said third boom member being positioned within said second boom member said second boom member being positioned within said first boom member and said first boom member being positioned within said base boom member, in the retracted position the inner ends of said first, second and third boom members closer to said turning bed being spaced outwardly from the end of said base boom member secured to said turning bed with the end of said second base member being spaced outwardly from the end of said first base member and the end of said third base member being spaced outwardly from the end of said second base member, a first hydraulic hoist is positioned between said base boom member and said second boom member and comprises an axially extending cylinder, a piston axially movable within said cylinder, and a piston rod secured to said piston and extending outwardly from said cylinder having an outer end spaced axially outwardly from said cylinder, the outer end of said piston rod being pin connected to said base boom member at a location between the inner end of said first boom member and the end of said base member secured to said turning bed and said cylinder connected at its inner end closer to said turning bed to the inner end of said first boom member, a second hydraulic hoist is positioned between said first boom member and said second boom member and comprises an axially extending cylinder a piston axially movable within said cylinder and a piston rod secured to said piston and extending axially therefrom outwardly from said cylinder toward said turning bed, said piston rod of said second hydraulic hoist being pin connected at its inner end to the inner end of said first boom member at approximately the same transverse location as the connection of said cylinder of said first hydraulic hoist to said first boom member and the inner end of said cylinder of said second hydraulic hoist being connected to the inner end of said second boom member, a third hydraulic hoist being positioned between said second and third boom members and comprising an axially extending cylinder, a piston axially movable within said cylinder, and a piston rod secured to said piston and extending outwardly from the outer end of said cylinder, said piston rod being secured at its inner end within said cylinder of said third hydraulic hoist to said piston therein and extending outwardly and being secured at its outer end to said third boom member at a point spaced intermediate the ends of said third boom member, said cylinder of said third hydraulic hoist being secured to said second boom member adjacent the inner end of said second boom member so that said first and second boom members are displaced outwardly into their extended positions by the action of said cylinders of said first and second hydraulic hoists riding outwardly on said piston rods and said third boom member is displaced outwardly by the action of said piston rod of said third hydraulic hoist being displaced outwardly from the cylinder of said third hydraulic hoist secured at its inner end to said second boom member, said piston rods of said first and seCond hydraulic hoists having a centrally arranged axially extending passageway and an annular axially extending passageway disposed concentrically about said central passageway, said piston in each of said cylinders of said first and second hydraulic hoists dividing the interior of said cylinder into a pair of variable volume chambers as said piston is moved between the extended and retracted positions, said centrally arranged passageway extending through said piston rod and said piston into the chamber located in the outer end of said cylinder and said annular passageway terminating in said piston rod before it reaches said piston and having an opening therefrom into the chamber on the opposite side of said piston from the other said chamber so that said annular passageway is connected to the chamber located in the cylinder closer to the turning bed, said chamber closer to said turning bed in said first and second hydraulic hoists having an opening extending through the end of said cylinders connected to said first and second boom members, respectively, the walls of said cylinders of said first and second hydraulic hoists providing a passageway extending for the length of said cylinder from the outer end thereof to the end of said cylinders located closer to said turning bed, and the inner end of said cylinder of said first hydraulic hoist being positioned adjacent the inner end of said piston rod of said second hydraulic hoist and the inner end of said cylinder of said second hydraulic hoist being positioned adjacent the inner end of the cylinder of said third hydraulic hoist so that the flow of hydraulic fluid for displacing said first, second and third boom members between the extended and retracted positions passes between the respective first, second and third hydraulic hoists without additional crossover connections and the interconnecting flow of hydraulic fluid between adjacent said hydraulic hoists are located at the inner ends of said cylinders of said hydraulic hoists.
References Cited (Backward Citations)
US3212604A
Cited
CH418560A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |