GB643462A - Improvements in and relating to two-speed rams for hydraulic machinery - Google Patents

Improvements in and relating to two-speed rams for hydraulic machinery

Info

Publication number
GB643462A
GB643462A GB405647A GB405647A GB643462A GB 643462 A GB643462 A GB 643462A GB 405647 A GB405647 A GB 405647A GB 405647 A GB405647 A GB 405647A GB 643462 A GB643462 A GB 643462A
Authority
GB
United Kingdom
Prior art keywords
duct
oil
valve
space
piston
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB405647A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SKYHI Ltd
Original Assignee
SKYHI Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SKYHI Ltd filed Critical SKYHI Ltd
Priority to GB405647A priority Critical patent/GB643462A/en
Publication of GB643462A publication Critical patent/GB643462A/en
Expired legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F3/00—Devices, e.g. jacks, adapted for uninterrupted lifting of loads
    • B66F3/24—Devices, e.g. jacks, adapted for uninterrupted lifting of loads fluid-pressure operated
    • B66F3/25—Constructional features
    • B66F3/42—Constructional features with self-contained pumps, e.g. actuated by hand

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Actuator (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

643,462. Hydraulic jacks. SKYHI, Ltd., and STEAD, A. H. Feb. 12, 1947, No. 4056. [Class 78 (iii)] A quick lifting device for the piston of a hydraulic jack comprises a small bore quick lift cylinder 6 located concentrically in the large bore of the hollow piston - rod 4, and a tubular guide 5 for this cylinder secured in the base of the jack. The piston 4a, together with the cylinder 6, quickly slides up the guide 5 when oil is pumped by a hand pump 8 through valve 8i, duct 1b and housing 7 to the interior of the guide 5, and the reduced pressure in the space 3a behind the piston 4a causes pre-filling valve 10 to open and admit oil from the reservoir 2 through duct 1e and aperture 7e. When the head 4h engages the load the space 3a is filled with oil which, under the pressure produced by the load closes valve 10 and thereafter oil is delivered to the space 3a by the pump 8 through duct 1b, housing 7 and non-return valve 11 until the load has been lifted to the required height. To lower the jack a release valve 9, connected to the reservoir through a duct (not shown) and to the duct 1b by a duct 1c is opened, the pressure in the cylinder 6 falls, after which the high pressure oil in the space 3a lifts the escape valve 12 and allows the oil to return to the reservoir via housing 7, ducts 1b, 1c and release valve 9.
GB405647A 1947-02-12 1947-02-12 Improvements in and relating to two-speed rams for hydraulic machinery Expired GB643462A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB405647A GB643462A (en) 1947-02-12 1947-02-12 Improvements in and relating to two-speed rams for hydraulic machinery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB405647A GB643462A (en) 1947-02-12 1947-02-12 Improvements in and relating to two-speed rams for hydraulic machinery

Publications (1)

Publication Number Publication Date
GB643462A true GB643462A (en) 1950-09-20

Family

ID=9769887

Family Applications (1)

Application Number Title Priority Date Filing Date
GB405647A Expired GB643462A (en) 1947-02-12 1947-02-12 Improvements in and relating to two-speed rams for hydraulic machinery

Country Status (1)

Country Link
GB (1) GB643462A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1084003B (en) * 1956-08-16 1960-06-23 Wilhelm Koenig Jun Hydraulic jack
DE1259542B (en) * 1965-12-30 1968-01-25 Weber Emil Hydraulic lifting device, preferably for raising and lowering frames or the like.
DE3910583A1 (en) * 1989-04-01 1990-10-04 Weber Oelhydraulik Hydraulic lifting unit for a lifting appliance
US6035635A (en) * 1998-09-03 2000-03-14 Hung; Michael Hydraulic quick lifting unit of a jack
WO2005007555A1 (en) * 2003-07-21 2005-01-27 Priborsky Dusan Hydraulic jack
CN103072920A (en) * 2013-01-05 2013-05-01 常熟通润汽车零部件股份有限公司 Oil pressure elevation device for carrying and transporting vehicle parts

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1084003B (en) * 1956-08-16 1960-06-23 Wilhelm Koenig Jun Hydraulic jack
DE1259542B (en) * 1965-12-30 1968-01-25 Weber Emil Hydraulic lifting device, preferably for raising and lowering frames or the like.
DE3910583A1 (en) * 1989-04-01 1990-10-04 Weber Oelhydraulik Hydraulic lifting unit for a lifting appliance
US6035635A (en) * 1998-09-03 2000-03-14 Hung; Michael Hydraulic quick lifting unit of a jack
WO2005007555A1 (en) * 2003-07-21 2005-01-27 Priborsky Dusan Hydraulic jack
CN103072920A (en) * 2013-01-05 2013-05-01 常熟通润汽车零部件股份有限公司 Oil pressure elevation device for carrying and transporting vehicle parts

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