US2597691A - Jack adapted for moving loads along a rod - Google Patents

Jack adapted for moving loads along a rod Download PDF

Info

Publication number
US2597691A
US2597691A US178296A US17829650A US2597691A US 2597691 A US2597691 A US 2597691A US 178296 A US178296 A US 178296A US 17829650 A US17829650 A US 17829650A US 2597691 A US2597691 A US 2597691A
Authority
US
United States
Prior art keywords
rod
cylinder
piston
gripping device
balls
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 - Lifetime
Application number
US178296A
Inventor
Wikstrom Nils Einar
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Application granted granted Critical
Publication of US2597691A publication Critical patent/US2597691A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04GSCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
    • E04G11/00Forms, shutterings, or falsework for making walls, floors, ceilings, or roofs
    • E04G11/06Forms, shutterings, or falsework for making walls, floors, ceilings, or roofs for walls, e.g. curved end panels for wall shutterings; filler elements for wall shutterings; shutterings for vertical ducts
    • E04G11/20Movable forms; Movable forms for moulding cylindrical, conical or hyperbolical structures; Templates serving as forms for positioning blocks or the like
    • E04G11/22Sliding forms raised continuously or step-by-step and being in contact with the poured concrete during raising and which are not anchored in the hardened concrete; Arrangements of lifting means therefor
    • E04G11/24Construction of lifting jacks or climbing rods for sliding forms
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02BHYDRAULIC ENGINEERING
    • E02B17/00Artificial islands mounted on piles or like supports, e.g. platforms on raisable legs or offshore constructions; Construction methods therefor
    • E02B17/04Equipment specially adapted for raising, lowering, or immobilising the working platform relative to the supporting construction
    • E02B17/08Equipment specially adapted for raising, lowering, or immobilising the working platform relative to the supporting construction for raising or lowering
    • E02B17/0836Equipment specially adapted for raising, lowering, or immobilising the working platform relative to the supporting construction for raising or lowering with climbing jacks
    • E02B17/0854Equipment specially adapted for raising, lowering, or immobilising the working platform relative to the supporting construction for raising or lowering with climbing jacks with clamping wedges, eccentric clamping devices and so on
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/15Intermittent grip type mechanical movement
    • Y10T74/1526Oscillation or reciprocation to intermittent unidirectional motion
    • Y10T74/1553Lever actuator

Definitions

  • each gripping device including a plurality of balls or rollers which are movable along a wall of a gripping device head converging towards the longitudinal axis of the rod in the direction of transport, and constantly lie applied against the rod by the action of resilient means.
  • Known jacks of this type have gripping devices with a plurality of ball rows, each including several balls, which rows extend in the longitudinal direction of the rod and are distributed around the rod, said balls being acted upon by a resilient means common to all balls in all rows.
  • These known jacks have many disadvantages, among which there may be mentioned that, like the known gripping devices having gripping members formed as toothed jaws, the gripping devices are very sensitive to Variations of diameter and our- Nature of the rod and that for this reason and due to the constructive length of the gripping devices which must be relatively long, the jacks are able to move the load a relatively short distance only between the changes of grip of the gripping devices.
  • Fig. 1 diagrammatically shows the arrangement of a jack according to the invention when raising a sliding mould for concrete casting
  • Fig. 2 shows the jack of Fig. 1 on an enlarged scale, partly in vertical projection and partly in section,
  • Fig. 3 shows a section'on line IIIIII of Fig. 2.
  • Movable inthe cylinder 5 is a piston 1 having a piston rod 8 which enters the housing 6 from the top of the cylinder 5.
  • the piston 1 has a central hole and the piston rod 8 is tubular for the passage of the rod 3.
  • the housing 6 has an end wall 9 with a central sleeve ID for the passage of the rod 3 while the cylinder has a threaded cover II at its lower end;
  • a gripping device to be-described in the following is secured to the said cover I i and is provided with a central hole for the passage of the rod 3.
  • the gripping device secured to the threaded cover I l consists of a head in the form of a ring l2 in which there are provided (in this instance) eight bores l3, the centre axes of which converge upwardly towards the longitudinal axis of the rod 3, i. e. in the direction of transport of the jack.
  • 3. are closed at the top by means of an annular cover 14 screwed onto the ring l2, but are open adjacent the top over part of their lengths towards the inner side of the ring l2.
  • the balls [5 constitute a single ring of rolling wedge means as will be apparent from the mode of operation later set forth.
  • a gripping device of the same type as that described above and having a ring [1, an annular cover I8, upwardly converging bores I9, balls 20 and springs 2
  • a return spring 22 tending to move the piston back to its upper end position shown in Fig. 2 after a stroke thereof, said end position being determined by the piston abutting against an annular distance member 23 attached to the upper end wall of the cylinder 5.
  • the housing 6 contains an additional return spring 24 which, during the latter part of the stroke of the piston l1 directed downwardly in relation to the cylinder, engages with the gripping device rings l1 and is compressed thereby for a purpose to be mentioned hereinafter.
  • On the said ring I! there is further fixed a pin or index 25 projecting from the housing 6 through a slot in order that it may be possible to determine the position of the piston 1 in the cylinder 5 from the outside.
  • the above jack operates in the following manner. It is assumed in Fig. 2 that the piston I has just been brought back into its upper end position in the cylinder and that the jack with its load is held applied to the rod 3 by the balls l5 of the gripping device of the cylinder being jammed between the wall portion of the bores I3 opposed to the rod 3 and the said rod 3.
  • the cylinder On continued delivery of pressure medium to the cylinder 5, the cylinder will therefore be raised in relation to the rod 3 which is permitted by the gripping device of the cylinder since the balls l5 are thereby moved downwards in the bores 13 away from their jamming grip around the rod against the action of the springs i6, During the raising of the cylinder 5 and thus of the sliding mould 2 along the rod 3 the piston 'l compresses the return spring 22 and at the end of the stroke of the piston in relation to the cylinder 5 the additional return spring 24 is also compressed by the ring [1. When the piston has reached the lower end position of its stroke in relation to the cylinder 5, the pressure medium is discharged from the cylinder.
  • the cylinder 5 then tries to slide downwardly along the rod 3 but this motion is stopped almost immediately by the balls [5 of the gripping device of the cylinder being jammed against the rod 3, thus interlocking the cylinder with the rod.
  • the return springs 22 and 24 press the piston I upwardly with great force so that the balls 20 of the gripping device of the piston are released from their jamming grip around the rod and the piston moves upwardly in the cylinder while discharging the fiuid in the upper part of the cylinder.
  • the additional return spring 24 aids in returning the piston during the first part of the movement only in order to help the spring 22 in releasing the balls 20 from their jamming grip around the rod 3.
  • the parts again occupy the position according to Fig. 2 so that a new raise of the cylinder along the rod 3 can take place by supply of pressure medium through the pipe 26.
  • a jack for moving loads along a rod comprising a cylinder, a piston movable in said cylinder by means of pressure fluid, one gripping device on said cylinder, and a second gripping device operatively associated with said piston, said two gripping devices automatically interlocking with the rod when the respective gripping device begins to move in one direction along the rod, and automatically releasing from the rod, when the respective gripping device moves in the other direction which is the direction of transport, said gripping devices includingeach only one single ring of rolling wedge means, circumscribing said rod and lying in a plane at right angles to the longitudinal axis of the rod, individual channel means on each of said gripping devices for separately mounting each of said rolling wedge means, said channel means having a wall opposing and converging towards the longitudinal axis of said rod in the direction of transport and along which the associated one of said rolling wedge means is adapted to roll into and out of wedging engagement with said rod, and a spring in each of said channel means urging the associated one of said rolling wedge means into engagement with said rod

Description

y 1952 N. E. WIKSTROM 2,597,691
JACK ADAPTED FOR MOVING LOADS ALONG A ROD Filed Aug. 8, 1950 B B EV Patented May 20, 1952 .OFFICE JACK ADAPTED FOR'MOVING LOADS ALONGAROD Nils Ilinar Wikstriim, Strangnas, Sweden Application August 8, 1950, Serial No; 178,296 In Sweden April 14, 1949 along the rod; and to be automatically released from the rod, when the respective gripping device moves in the other direction, which is the direction of transport, each gripping device including a plurality of balls or rollers which are movable along a wall of a gripping device head converging towards the longitudinal axis of the rod in the direction of transport, and constantly lie applied against the rod by the action of resilient means.
Known jacks of this type have gripping devices with a plurality of ball rows, each including several balls, which rows extend in the longitudinal direction of the rod and are distributed around the rod, said balls being acted upon by a resilient means common to all balls in all rows. These known jacks have many disadvantages, among which there may be mentioned that, like the known gripping devices having gripping members formed as toothed jaws, the gripping devices are very sensitive to Variations of diameter and our- Nature of the rod and that for this reason and due to the constructive length of the gripping devices which must be relatively long, the jacks are able to move the load a relatively short distance only between the changes of grip of the gripping devices.
The principal object of the ,present invention is to provide a jack construction avoiding the above-mentioned disadvantages of the known jacks of said type. Other objects of the invention will be clear to those skilled in the art from the following description of a preferred embodiment of the invention shown in the accompanying drawings, in which? Fig. 1 diagrammatically shows the arrangement of a jack according to the invention when raising a sliding mould for concrete casting,
Fig. 2 shows the jack of Fig. 1 on an enlarged scale, partly in vertical projection and partly in section,
Fig. 3 shows a section'on line IIIIII of Fig. 2.
2 Claims. (01. 254? 106) able mannerfrom the topof a cylinder 5 included in the jack around a cylindrical housing 6 secured to the top of the cylinder.
Movable inthe cylinder 5 is a piston 1 having a piston rod 8 which enters the housing 6 from the top of the cylinder 5. The piston 1 has a central hole and the piston rod 8 is tubular for the passage of the rod 3. At the top the housing 6 has an end wall 9 with a central sleeve ID for the passage of the rod 3 while the cylinder has a threaded cover II at its lower end; A gripping device to be-described in the following is secured to the said cover I i and is provided with a central hole for the passage of the rod 3.
The gripping device secured to the threaded cover I l consists of a head in the form of a ring l2 in which there are provided (in this instance) eight bores l3, the centre axes of which converge upwardly towards the longitudinal axis of the rod 3, i. e. in the direction of transport of the jack. The bores |3.are closed at the top by means of an annular cover 14 screwed onto the ring l2, but are open adjacent the top over part of their lengths towards the inner side of the ring l2. Inserted in each bore I3 is a ball [5 which is pressed upwardly therein by a spring [6 whereby the ball will be held constantly applied against the rod. The balls [5 constitute a single ring of rolling wedge means as will be apparent from the mode of operation later set forth.
Attached "to the upper end of the piston rod 8 which is movable in the casing 6 is a gripping device of the same type as that described above and having a ring [1, an annular cover I8, upwardly converging bores I9, balls 20 and springs 2| and here the balls 20 constitute a single ring of rolling wedge means.
Below the piston I there is arranged in the cylinder 5 a return spring 22 tending to move the piston back to its upper end position shown in Fig. 2 after a stroke thereof, said end position being determined by the piston abutting against an annular distance member 23 attached to the upper end wall of the cylinder 5. The housing 6 contains an additional return spring 24 which, during the latter part of the stroke of the piston l1 directed downwardly in relation to the cylinder, engages with the gripping device rings l1 and is compressed thereby for a purpose to be mentioned hereinafter. On the said ring I! there is further fixed a pin or index 25 projecting from the housing 6 through a slot in order that it may be possible to determine the position of the piston 1 in the cylinder 5 from the outside.
The above jack operates in the following manner. It is assumed in Fig. 2 that the piston I has just been brought back into its upper end position in the cylinder and that the jack with its load is held applied to the rod 3 by the balls l5 of the gripping device of the cylinder being jammed between the wall portion of the bores I3 opposed to the rod 3 and the said rod 3.
When a pressure medium, e. g. pressure oil, is now delivered through a supply pipe 26 to the cylinder 5 between the top of the piston and the upper end wall of the cylinder, the piston 'l is depressed downwardly in relation to the cylinder 5 and the rod 3. When this downward movement starts, the balls 20 of the gripping device mounted on the piston rod are however jammed between the rod and the wall portions of the bores l9 in the ring H, opposed to the rod, whereby the gripping device of the piston is arrested on the rod 3 and the piston I is prevented from moving downwardly in relation to the rod 3. On continued delivery of pressure medium to the cylinder 5, the cylinder will therefore be raised in relation to the rod 3 which is permitted by the gripping device of the cylinder since the balls l5 are thereby moved downwards in the bores 13 away from their jamming grip around the rod against the action of the springs i6, During the raising of the cylinder 5 and thus of the sliding mould 2 along the rod 3 the piston 'l compresses the return spring 22 and at the end of the stroke of the piston in relation to the cylinder 5 the additional return spring 24 is also compressed by the ring [1. When the piston has reached the lower end position of its stroke in relation to the cylinder 5, the pressure medium is discharged from the cylinder. To begin with, the cylinder 5 then tries to slide downwardly along the rod 3 but this motion is stopped almost immediately by the balls [5 of the gripping device of the cylinder being jammed against the rod 3, thus interlocking the cylinder with the rod. Instead the return springs 22 and 24 press the piston I upwardly with great force so that the balls 20 of the gripping device of the piston are released from their jamming grip around the rod and the piston moves upwardly in the cylinder while discharging the fiuid in the upper part of the cylinder. The additional return spring 24 aids in returning the piston during the first part of the movement only in order to help the spring 22 in releasing the balls 20 from their jamming grip around the rod 3. Then the parts again occupy the position according to Fig. 2 so that a new raise of the cylinder along the rod 3 can take place by supply of pressure medium through the pipe 26.
What I claim and desire to secure by Letters Patent is:
1. A jack for moving loads along a rod, comprising a cylinder, a piston movable in said cylinder by means of pressure fluid, one gripping device on said cylinder, and a second gripping device operatively associated with said piston, said two gripping devices automatically interlocking with the rod when the respective gripping device begins to move in one direction along the rod, and automatically releasing from the rod, when the respective gripping device moves in the other direction which is the direction of transport, said gripping devices includingeach only one single ring of rolling wedge means, circumscribing said rod and lying in a plane at right angles to the longitudinal axis of the rod, individual channel means on each of said gripping devices for separately mounting each of said rolling wedge means, said channel means having a wall opposing and converging towards the longitudinal axis of said rod in the direction of transport and along which the associated one of said rolling wedge means is adapted to roll into and out of wedging engagement with said rod, and a spring in each of said channel means urging the associated one of said rolling wedge means into engagement with said rod.
2. A jack according to claim 1, in which said rolling wedge means consist of balls.
NILS EINAR WIKsTRoM.
No references cited.
US178296A 1949-04-14 1950-08-08 Jack adapted for moving loads along a rod Expired - Lifetime US2597691A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE2597691X 1949-04-14

Publications (1)

Publication Number Publication Date
US2597691A true US2597691A (en) 1952-05-20

Family

ID=20426447

Family Applications (1)

Application Number Title Priority Date Filing Date
US178296A Expired - Lifetime US2597691A (en) 1949-04-14 1950-08-08 Jack adapted for moving loads along a rod

Country Status (1)

Country Link
US (1) US2597691A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2648985A (en) * 1951-10-22 1953-08-18 Louis V Mallory Hoisting and stretching apparatus
US2673067A (en) * 1951-05-07 1954-03-23 Minot Builders Supply Co Inc Jack for raising forms and flooring in erection of concrete buildings
US2775869A (en) * 1952-04-22 1957-01-01 L B De Long Platform construction
US2969648A (en) * 1956-12-27 1961-01-31 Bethlehem Steel Corp Mobile drilling platform and method of operation
US20020117016A1 (en) * 2001-02-20 2002-08-29 Beckett Clifford Edward Hand actuated tool and clutch mechanism

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2673067A (en) * 1951-05-07 1954-03-23 Minot Builders Supply Co Inc Jack for raising forms and flooring in erection of concrete buildings
US2648985A (en) * 1951-10-22 1953-08-18 Louis V Mallory Hoisting and stretching apparatus
US2775869A (en) * 1952-04-22 1957-01-01 L B De Long Platform construction
US2969648A (en) * 1956-12-27 1961-01-31 Bethlehem Steel Corp Mobile drilling platform and method of operation
US20020117016A1 (en) * 2001-02-20 2002-08-29 Beckett Clifford Edward Hand actuated tool and clutch mechanism
US6745921B2 (en) * 2001-02-20 2004-06-08 P.C. Cox Limited Hand actuated tool and clutch mechanism

Similar Documents

Publication Publication Date Title
GB929946A (en) Improvements in or relating to double acting quick release pins
US2597691A (en) Jack adapted for moving loads along a rod
GB1437515A (en) Hydraulic drive for operating an elevator
US1779123A (en) Hydraulic casing spear
US2437014A (en) Dental and surgical hammer
US3656411A (en) Telescopic props
GB1026419A (en) Improvements in hydraulic pis ton and cylinder combinations
US682536A (en) Hydraulic cable safety device.
US2525687A (en) Separation device for rolling mills
US4352318A (en) Expandable cushion plunger for piston and cylinder devices
GB984952A (en) Fluid motor piston mechanism
US2786451A (en) Pneumatic rotary drill hammer
US3382929A (en) Oil well tools
US2172480A (en) Jar
US2057699A (en) Airplane and parachute connecting device
US3424093A (en) Pneumatically driven plunger construction
GB667550A (en) A jack adapted for moving loads along a rod
RU2018628C1 (en) Hydraulic packer of multiple use
JPS6138286B2 (en)
US2947086A (en) Release assembly for tubing caliper
SU421734A1 (en)
SE419900B (en) DISCONNECTING DEVICE, SEPARATE FOR RELEASING A MINA FROM ITS ANCHOR
SU566979A1 (en) Ball lock of a cylinder-piston assembly
US1051999A (en) Molding-machine.
SU371163A1 (en) HYDRAULIC JACK