Patent US3777629A successfully refreshed from Google Patents.
US3777629A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic cylinder for telescopic boom
Assignee: Harnischfeger Corp
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Filing: 1972-09-18
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Granted: 1973-12-11
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Expires: 1992-09-18
Abstract
Abstract A mobile crane has a boom comprising a plurality of telescopic hollow boom sections. Hydraulic operating cylinders for the boom sections are housed within the boom and each is provided with its own remotely operable electrically controlled main valve. Each cylinder comprises a housing and a rod therein which cooperate to define an extend chamber and a separate retract chamber. Passages in the rod connect these chambers to ports on the main control valve which is mounted on the rod. Hydraulic fluid is supplied to the valves by flexible hydraulic fluid hoses disposed between the side plates of adjacent boom sections and the hoses uncoil or coil in a frictionless manner as the sections are extended or retracted.
Inventors
- 👤 R Johnston
- 👤 D Wiencek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:45
CPC Classifications
F; F15; F15B; F15B21/00; F15B21/08; B; B66; B66C; B66C23/00; B66C23/62; B66C23/64; B66C23/70; B66C23/701; B66C23/705
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
142 words
A hydraulic cylinder assembly comprising: a tubular housing enclosed at one end and open at the other, supporting means on said housing located intermediate the ends of said housing, a tubular cylinder rod enclosed at one end and open at the other extending into said housing, supporting means on said rod located near one end thereof, said housing and rod cooperating to define a retraction chamber and to define an expansion chamber, sealing means carried by said rod to separate said retraction chamber an said expansion chamber, sealing means carried by said cylinder to seal the other end of said retraction chamber, a first fluid passage in said rod communicating with said retraction chamber, a second fluid passage in said rod communicting with said expansion chamber, and a valve on said cylinder rod for controlling fluid flow to and from said passages.
Claim 2
Dependent Claim
142 words
A hydraulic cylinder assembly comprising: a tubular housing enclosed at one end and open at the other, supporting means on said housing located intermediate the ends of said housing, a tubular cylinder rod enclosed at one end and open at the other extending into said housing, supporting means on said rod located near one end thereof, said housing and rod cooperating to define a retraction chamber and to define an expansion chamber, sealing means carried by said rod to separate said retraction chamber an said expansion chamber, sealing means carried by said cylinder to seal the other end of said retraction chamber, a first fluid passage in said rod communicating with said retraction chamber, a second fluid passage in said rod communicting with said expansion chamber, and a valve on said cylinder rod for controlling fluid flow to and from said passages.
Claim 3
Dependent Claim
12 words
An assembly according to claim 1 wherein said valve is remotely operable.
Claim 4
Dependent Claim
12 words
An assembly according to claim 2 wherein said valve is electrically operable.
Claim 5
Dependent Claim
21 words
An assembly according to claim 2 including a holding valve mounted on said rod for preventing retract operation of said cylinder.
Claim 6
Dependent Claim
129 words
A hydraulic cylinder assembly for use in a telescopic boom comprising at least two relatively movable boom sections comprising: a housing, means on said housing located near the middle of said housing to secure the assembly to one of said boom sections, a cylinder rod extending into said housing, means on said rod located near an end of said rod to secure the assembly to the other of said boom sections, said housing and said rod cooperating to define a retraction chamber and a separate expansion chamber, a remotely operable control valve mounted on said rod and having two fluid ports, a first passage in said rod interconnecting one port and said expansion chamber, and a second passage in said rod interconnecting the other port and said retraction chamber.
Claim 7
Dependent Claim
129 words
A hydraulic cylinder assembly for use in a telescopic boom comprising at least two relatively movable boom sections comprising: a housing, means on said housing located near the middle of said housing to secure the assembly to one of said boom sections, a cylinder rod extending into said housing, means on said rod located near an end of said rod to secure the assembly to the other of said boom sections, said housing and said rod cooperating to define a retraction chamber and a separate expansion chamber, a remotely operable control valve mounted on said rod and having two fluid ports, a first passage in said rod interconnecting one port and said expansion chamber, and a second passage in said rod interconnecting the other port and said retraction chamber.
Claim 8
Dependent Claim
14 words
An assembly according to claim 5 including a holding valve mounted on said rod.
Claim 9
Dependent Claim
187 words
In a telescopic boom: a plurality of linearly movable boom sections; a plurality of hydraulic cylinder assemblies, one assembly for each movable section, each cylinder assembly comprising: a housing, means on said housing intermediate the ends of said housing to secure the assembly to one of said boom sections, a cylinder rod extending into said housing, means on said rod near an end thereof to secure the assembly to another of said boom sections, said housing and said rod cooperating to define a retraction chamber and a separate expansion chamber; a remotely operable control valve mounted on said rod and having two fluid control ports and two other fluid ports, a first passage in said rod interconnecting one of said other fluid ports and said expansion chamber, a second passage in said rod interconnecting the other of said other fluid ports and said retraction chambers; and two pairs of hoses for said valve, each pair of hoses connected to the fluid control ports of said valve, one hose in each pair being a fluid supply hose and the other hose in each pair a fluid return hose.
Claim 10
Dependent Claim
187 words
In a telescopic boom: a plurality of linearly movable boom sections; a plurality of hydraulic cylinder assemblies, one assembly for each movable section, each cylinder assembly comprising: a housing, means on said housing intermediate the ends of said housing to secure the assembly to one of said boom sections, a cylinder rod extending into said housing, means on said rod near an end thereof to secure the assembly to another of said boom sections, said housing and said rod cooperating to define a retraction chamber and a separate expansion chamber; a remotely operable control valve mounted on said rod and having two fluid control ports and two other fluid ports, a first passage in said rod interconnecting one of said other fluid ports and said expansion chamber, a second passage in said rod interconnecting the other of said other fluid ports and said retraction chambers; and two pairs of hoses for said valve, each pair of hoses connected to the fluid control ports of said valve, one hose in each pair being a fluid supply hose and the other hose in each pair a fluid return hose.
Claim 11
Dependent Claim
21 words
A boom according to claim 7 wherein each hose is in a looped arrangement between the valves of adjacent cylinder assemblies.
Claim 12
Dependent Claim
21 words
An assembly according to claim 5 wherein said means on said rod and said means on said housing are trunnion-type mounts.
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) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |