US3481490A - Telescopic jib for jib cranes - Google Patents

Telescopic jib for jib cranes Download PDF

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Publication number
US3481490A
US3481490A US3481490DA US3481490A US 3481490 A US3481490 A US 3481490A US 3481490D A US3481490D A US 3481490DA US 3481490 A US3481490 A US 3481490A
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Prior art keywords
jib
rollers
surfaces
pair
components
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Peter Eiler
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LEO GOTTWALD KG
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LEO GOTTWALD KG
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66CCRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C23/00Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
    • B66C23/62Constructional features or details
    • B66C23/64Jibs
    • B66C23/70Jibs constructed of sections adapted to be assembled to form jibs or various lengths
    • B66C23/701Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic
    • B66C23/707Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic guiding devices for telescopic jibs

Description

Dec. 2, 1.969l

P. EILER TELESCOPIC JIB FOR JIB CRANES Filed June 29, 1967 I lllllflflllllllf IIII l..

United States Patent O 3,481,490 TELESCOPIC .IIB FOR JIB CRANES Peter Eiler, Langenfeld, Rhineland, Germany, assignor to Leo Gottwald K.G., Dusseldorf, Germany Filed June 29, 1967, Ser. No. 649,930 Claims priority, application Grmany, `lune 30, 1966,

Int. c1. Base 23/06, 23/68 U.S. Cl. 212-55 8 Claims ABSTRACT OF THE DISCLOSURE The invention relates to jib cranes having a telescopic jib.

In existing forms of telescopic jibs', the jib components are manufactured from rolled sections or welded box structures, which on their underside have horizontally disposed running or sliding surfaces for cooperation with skids or slide shoes carried by the other and lower component. Known constructions are complicated, expensive and have inadequate guidance of the telescopic components, with static stressing which is difficult to assess.

The aim underlying this invention is to provide a telescopically extensible and retractable jib for a crane which overcomes the disadvantages of known jibsI and in which the ratio of useful load to dead weight is higher.

According to the invention, in a crane jib of the type set out, by forming at least part of the box sections with bevelled wall portions there is provided on the one hand running or guide tracks and on the other hand the supports for rollers or slide shoes which have axes extending parallel to the bevels. This arrangement of the operative surfaces or guide tracks ensures that the rigidity of the entire construction is further increased. In addition, lateral guidance of the inner box is achieved, such as could be obtained in known jibs only with the aid of additional rollers disposed on the verticals. Satisfactory results with improved guidancepperformance of the individual jib components have been obtained where the bevels are at an angle of about 45 to the side walls. Furthermore, a crane jib constructed in acocrdance with the invention has a substantially lower weight than that of comparable crane jibs and in the case of slewing cranes this is synonymous with the ability to bear a greater useful load. At the same time the jib can carry heavier loads, since its jib components consist of a torsionally stii structure'.

According to a further feature of the invention, each box section of the jib is assembled by welding together two sheet metal parts, previously folded into U-form, thereby enabling particularly simple manufacturing meth ods to be employed. Moreover, those sheet metal parts subjected to greater stresses can -be made of thicker guage sheet than the less stressed part. Thus, the bottom portion of the box section, which is subjected to compression stressing, can be made of thicker sheet than the other portion which is under tension. Crane jibs constructed in this manner can thus be adapted in an optimum manner to varying loads.

One embodiment of the invention is described and illustrated in the drawingsI in which:

Tice

FIGURE 1 is a side elevation of a telescopic jib having two telescoping portions according to the invention;

FIGURE 2 is a transverse section on the line II-II of FIGURE l, and

FIGURE 3 is a transverse section on the line III-III of FIGURE 1.

Referring to the drawings, the crane jib consists of two components 1, 2, of box-shaped section, which are nested one within the other, .the upper or movable jib com-ponent 1 carrying the head sheave bracket 3 being telescopically extensible and retractable in relation to the lower and static jib component 2, the latter being mounted for luing movements about a fulcrum on the slewing base. On the cross-head 3 are guide rollers or pulleys 4 for the lifting ropes 5 or the like. At its inner end the jib component 1 is provided with rollers 6 which engage running surfaces 7 (FIGURE 2) on the inside of jib component 2. The rollers 6, as can be seen from FIG- URE l, are mounted on the upper side of the inner end of the moveable component 1, since, when under load, that end is thrust against the top wall of the stationary component 2, as in a lever, Iwith the rollers 8 `acting as a fulcrum. The rollers 8 are fastened on the underside of the component 2 and roll on running surfaces 9 (FIG- URE 3) provided at the corners and on the outside of the underside of the jib component 1.

As can be seen from FIGURES 2 and 3, the job components 1, 2, consist of box sections. These box sections may be assembled by uniting two folded metal sheets along weld seams 15. Each box section, at least at its edges, has longitudinally extending bevelled surfaces 7 and 9 with which surfaces engage rollers 6 and 8 respectively which are disposed on the other box section in each case. The moveable jib part 1 is constructed at its bottom .bevel with external bearing sur-faces 9, and the jib part 2, which is stationary, relative to the jib portion 1, is constructed on the inside at its upper bevel with internal bearing surfaces 7.

On the other hand the bevels 10, 11 to which are secured the support brackets 12, 13 for the rollers 6, 8, need to be provided only at the sections in which the rollers are located.

In order to provide additional stiffening and to accommodate the support surfaces 11 for the rollers 8, the stationary jib component 2 has at its outer end an additional box section 14 which is attached thereto such as by Welding. The roller surfaces 7 and 9 together with the axes of the rollers 6 and 8 are preferably inclined by about 45 in relation to the side walls, which has been shown to give good lateral guidance of the jib portions in relation to one another. It also ensures that the sheets are subjected to minimum stress during folding.

The weld seams v15 in the box sections preferably lie in the neutral fibre, i.e. approximately at the mid-point of the vertical wall, so that they are not unduly stressed. In addition, it is possible for folded sheet metal sections of different thicknesses to be used so that the bottom sheet which is subjected to heavier compressive loads is thicker than the top sheet where the tensile loads is less. For the purpose of taking the supporting forces, transverse stiffening webs or plates 16 (FIGURE 2) are disposed in the jib component 1 on both sides of the rollers 6. In order to ensure uniform loading of the rollers 6, 8, they are mounted on a rocker. In the embodiment illustrated only two jib sections are shown but clearly the invention is also aplicable where more than two jib component's are telescopically displaceable in relation to one another.

It will be seen that the present invention provides guide surfaces 7, 9, arranged in pairs and respectively 0n each of the box sections 1, 2 or other jib components, these guide surfaces 7, 9 being located upwardly and downwardly in relation to the longitudinal axis of the jib, the upper pair of surfaces 7 preferably facing inwardly and the faces of the lower pair 9 facing outwardly, for cooperation with thrust rollers or skids similarly arranged in pairs and provided on the other one of each of the box sections 1, 2. The axes of each pair of rollers and also their associated guide surfaces are at an angle to one another less than a straight angle and preferably such that the guide surfaces are at an angle of 45 or approximately 45 to the sides of the box sections or other components.

What is claimed is:

1. In a jib crane comprising a jib having at least two telescoping components the improvements in which each of said components is provided with a pair of substantially planar guide surfaces, the surfaces being angled in relation to one another so that the surfaces of one pair face inwardly and those of the other face outwardly, said components being provided with pairs of thrust elements, one pair of elements in relation to the longitudinal axis of the jib being located on the underside and the other pair on the upperside of their respective components, said pairs of elements having faces in slidable engagement respectively with said pairs of substantially planar guide surfaces, said faces having a width smaller than that of said substantially planar guide surfaces, the elements in each pair being spaced laterally and so arranged that the slidably engaging faces thereof extend in planes disposed at an angle corresponding to the angle at which the respective guide surfaces are disposed.

2. A jib crane as claimed in claim 1 wherein the guide surfaces extend in planes which are at angles of approximately 90 to one another.

3. In a jib crane comprising a jib having at least two telescoping components, the improvement in which each one of said components is provided with a pair of substantially planar guide surfaces, the surfaces being at an angle to one another with respect to the longitudinal axis of the jib so that the surfaces of one pair face inwardly and those of the other pair face outwardly, each of said components being provided with pairs of thrust rollers, one pair of rollers being located on the underside of one component and the other pair on the upperside of the other component for cooperation respectively with said pairs of guide surfaces, said thrust rollers having peripheral surfaces of a width smaller than that of said substantially planar guide surfaces, and the rollers in each pair being spaced laterally and being journalled to revolve about axes in a transverse plane, said axes at their point of intersection subtending an angle corresponding to the angle subtended by the guide surfaces.

4. A jib crane as claimed in claim 3 comprising a jib having telescoping components formed of box section members wherein the guide surfaces on the one member extend in planes which are at an angle of substantially 45 to the side walls thereof.

5. A jib crane as claimed in claim 4 wherein each box section member is fabricated from strip metal of U- section assembled end to end and united by weld seams.

6. A jib crane as claimed in claim 5 wherein the weld seam is located in the neutral area of the jib.

7. A jib crane as claimed in claim 6 wherein the box section members are fabricated from metal of different thicknesses, that subjected to greater stress being of increased thickness.

8. An extending jib for a crane comprising two telescopically arranged box-section members, angled substantially planar guide surfaces on one of said members and longitudinally spaced pairs of thrust members having faces for sliding engagement with said guide surfaces, said faces being smaller in width than said substantially planar guide surfaces, an inboard pair of rollers being adjacent the upper sides of said members, and an outboard pair of rollers being adjacent the lower sides of said members, the axes of the rollers being inclined so that the projected axes of each pair meet respectively above and below said members, and the guide surfaces being arranged in planes which are at corresponding angles.

References Cited UNITED STATES PATENTS 2,684,159 7/1954 Olenkamp 212-55 2,746,612 5/1956` Wirz 212-55 2,817,447 12/1957 Bianca 254-150 2,984,373 5/1961 Przybylski 214-141 3,322,206 5/ 1967 Gernhardt 212-55 FOREIGN PATENTS 1,164,334 2/ 1964 Germany.

HARVEY C. HORNSBY, Primary Examiner U.S. C1. X.R. 308-6

US3481490A 1966-06-30 1967-06-29 Telescopic jib for jib cranes Expired - Lifetime US3481490A (en)

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DE1966G0047320 DE1281651C2 (en) 1966-06-30 1966-06-30 Telescopically on and extendable crane boom

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GB (1) GB1122936A (en)

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3685673A (en) * 1970-05-28 1972-08-22 Crutcher Resources Side-loading self-propelled material transporting device
US3690742A (en) * 1971-11-19 1972-09-12 Grove Mfg Co Crane boom
US3802136A (en) * 1972-01-26 1974-04-09 Gottwald Kg Leo Extendible crane boom formed of telescopic box-shaped sections
US3807108A (en) * 1972-09-18 1974-04-30 Harnischfeger Corp Structural design of boom section with inverted {37 a{38 {11 frame cross-section
US3978957A (en) * 1973-11-13 1976-09-07 Fried. Krupp Gesellschaft Mit Beschrankter Haftung Hollow guiding mast for a charging device of a core reactor
US4004695A (en) * 1975-04-16 1977-01-25 Fulton Industries, Inc. Channel and plate telescopic crane boom
FR2329580A1 (en) * 1975-10-28 1977-05-27 Warner Swasey Co Crane Fleche
US4257201A (en) * 1979-04-19 1981-03-24 American Hoist & Derrick Company Self-centering telescoping beams
FR2502132A1 (en) * 1981-03-18 1982-09-24 Ppm Sa Telescopic jib for crane - has sections sliding on guide rollers fitted at intervals and following section contours
US4390315A (en) * 1978-05-18 1983-06-28 Hydra Rig Incorporated Fire fighting boom assembly for service vessel
US4534697A (en) * 1982-06-17 1985-08-13 Allibert S.A. Transfer device for robots
FR2600384A1 (en) * 1986-06-19 1987-12-24 Lamy Perret Paul Guidance device for a telescopic arm, especially for a manipulator
EP0583552A1 (en) * 1992-08-14 1994-02-23 LIEBHERR-WERK EHINGEN GmbH Telescopic jib for mobile cranes or the like
US5465854A (en) * 1993-07-30 1995-11-14 Par Systems, Inc. Telescoping tube assembly
US5762467A (en) * 1996-04-26 1998-06-09 Par Systems, Inc. Underground storage tank manipulator
US5865328A (en) * 1993-06-16 1999-02-02 Ec Engineering + Consulting Spezialmaschinen Gmbh Telescopic boom
EP0922664A2 (en) * 1997-12-12 1999-06-16 Grove U.S. LLC Telescopic jib bearing assembly with embossments
US20020045172A1 (en) * 2000-06-30 2002-04-18 Sturm Albert J. Segmented support structure and method and fixture for making the same
US6499612B1 (en) 2001-07-27 2002-12-31 Link-Belt Construction Equipment Co., L.P., Lllp Telescoping boom assembly with rounded profile sections and interchangeable wear pads
US6561368B1 (en) 2000-05-01 2003-05-13 Par Systems, Inc. Telescoping tube assembly with a cabling system
US20070098536A1 (en) * 2005-10-31 2007-05-03 Kooima Roger D Extendable telescoping boom and method of manufacturing
US20070172032A1 (en) * 1999-11-30 2007-07-26 Shook Mobile Technology, L.P. Boom with mast assembly
US20080164233A1 (en) * 2007-01-10 2008-07-10 Stellar Industries, Inc. Roller boom rest
US7624967B1 (en) 2006-04-19 2009-12-01 Par Systems, Inc. Opposed-rope hoist driven telescoping mast
US20100011731A1 (en) * 2008-07-08 2010-01-21 Bart Moutton Guides for an extendable harvesting header
US20120085723A1 (en) * 2010-10-08 2012-04-12 Liebherr-Werk Ehingen Gmbh Boom element, telescopic boom and construction vehicle
CN102887443A (en) * 2011-07-21 2013-01-23 马尼托瓦克起重机有限责任公司 Tailor welded panel beam for construction machine and method of manufacturing
CN103174715A (en) * 2011-12-23 2013-06-26 苏州海伦哲专用车辆有限公司 Telescopic boom sliding block device
US9033165B2 (en) 2011-02-09 2015-05-19 Oshkosh Corporation Crane assembly

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2148966C3 (en) * 1971-09-30 1978-11-23 Liebherr-Werk Ehingen Gmbh, 7930 Ehingen
US4417424A (en) * 1980-01-07 1983-11-29 Jacobson Darwin J Segmented extendible boom
CN103241663A (en) * 2013-05-07 2013-08-14 三一帕尔菲格特种车辆装备有限公司 Crane, and telescopic arm and knuckle arm thereof

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2684159A (en) * 1950-07-12 1954-07-20 Warner Swasey Co Telescoping boom actuating mechanism
US2746612A (en) * 1952-07-12 1956-05-22 Wirz Ernst Crane truck
US2817447A (en) * 1954-07-27 1957-12-24 Sicomatic A G Shunting arrangements for moving vehicles or the like
US2984373A (en) * 1958-07-16 1961-05-16 Warner Swasey Co Material handling apparatus
DE1164334B (en) * 1959-10-17 1964-02-27 Krupp Druckenmueller G M B H Strut for stiffening of Baugrubenwaenden
US3322206A (en) * 1964-10-09 1967-05-30 Ohio Brass Co Earth borer

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1009373B (en) * 1953-05-11 1957-05-29 Walter Alfred Golka telescopic boom
US3082881A (en) * 1960-04-20 1963-03-26 Wieger Ernst Telescopically variable overhang beam for dredges, cranes, and the like
DE1923569U (en) * 1964-02-22 1965-09-16 Krause Kg Robert Adjusting for moebelstuecke.

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2684159A (en) * 1950-07-12 1954-07-20 Warner Swasey Co Telescoping boom actuating mechanism
US2746612A (en) * 1952-07-12 1956-05-22 Wirz Ernst Crane truck
US2817447A (en) * 1954-07-27 1957-12-24 Sicomatic A G Shunting arrangements for moving vehicles or the like
US2984373A (en) * 1958-07-16 1961-05-16 Warner Swasey Co Material handling apparatus
DE1164334B (en) * 1959-10-17 1964-02-27 Krupp Druckenmueller G M B H Strut for stiffening of Baugrubenwaenden
US3322206A (en) * 1964-10-09 1967-05-30 Ohio Brass Co Earth borer

Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3685673A (en) * 1970-05-28 1972-08-22 Crutcher Resources Side-loading self-propelled material transporting device
US3690742A (en) * 1971-11-19 1972-09-12 Grove Mfg Co Crane boom
US3802136A (en) * 1972-01-26 1974-04-09 Gottwald Kg Leo Extendible crane boom formed of telescopic box-shaped sections
US3807108A (en) * 1972-09-18 1974-04-30 Harnischfeger Corp Structural design of boom section with inverted {37 a{38 {11 frame cross-section
US3978957A (en) * 1973-11-13 1976-09-07 Fried. Krupp Gesellschaft Mit Beschrankter Haftung Hollow guiding mast for a charging device of a core reactor
US4004695A (en) * 1975-04-16 1977-01-25 Fulton Industries, Inc. Channel and plate telescopic crane boom
FR2329580A1 (en) * 1975-10-28 1977-05-27 Warner Swasey Co Crane Fleche
US4038794A (en) * 1975-10-28 1977-08-02 The Warner & Swasey Company Boom assembly
US4390315A (en) * 1978-05-18 1983-06-28 Hydra Rig Incorporated Fire fighting boom assembly for service vessel
US4257201A (en) * 1979-04-19 1981-03-24 American Hoist & Derrick Company Self-centering telescoping beams
FR2502132A1 (en) * 1981-03-18 1982-09-24 Ppm Sa Telescopic jib for crane - has sections sliding on guide rollers fitted at intervals and following section contours
US4534697A (en) * 1982-06-17 1985-08-13 Allibert S.A. Transfer device for robots
FR2600384A1 (en) * 1986-06-19 1987-12-24 Lamy Perret Paul Guidance device for a telescopic arm, especially for a manipulator
EP0583552A1 (en) * 1992-08-14 1994-02-23 LIEBHERR-WERK EHINGEN GmbH Telescopic jib for mobile cranes or the like
US5865328A (en) * 1993-06-16 1999-02-02 Ec Engineering + Consulting Spezialmaschinen Gmbh Telescopic boom
US5465854A (en) * 1993-07-30 1995-11-14 Par Systems, Inc. Telescoping tube assembly
US5762467A (en) * 1996-04-26 1998-06-09 Par Systems, Inc. Underground storage tank manipulator
EP0922664A2 (en) * 1997-12-12 1999-06-16 Grove U.S. LLC Telescopic jib bearing assembly with embossments
US6086256A (en) * 1997-12-12 2000-07-11 Grove U.S. L.L.C. Telescopic jib bearing assembly with embossments
EP0922664A3 (en) * 1997-12-12 1999-10-20 Grove U.S. LLC Telescopic jib bearing assembly with embossments
US20070172032A1 (en) * 1999-11-30 2007-07-26 Shook Mobile Technology, L.P. Boom with mast assembly
US6561368B1 (en) 2000-05-01 2003-05-13 Par Systems, Inc. Telescoping tube assembly with a cabling system
US20020045172A1 (en) * 2000-06-30 2002-04-18 Sturm Albert J. Segmented support structure and method and fixture for making the same
US6499612B1 (en) 2001-07-27 2002-12-31 Link-Belt Construction Equipment Co., L.P., Lllp Telescoping boom assembly with rounded profile sections and interchangeable wear pads
US20070098536A1 (en) * 2005-10-31 2007-05-03 Kooima Roger D Extendable telescoping boom and method of manufacturing
US7624967B1 (en) 2006-04-19 2009-12-01 Par Systems, Inc. Opposed-rope hoist driven telescoping mast
US20080164233A1 (en) * 2007-01-10 2008-07-10 Stellar Industries, Inc. Roller boom rest
US20100011731A1 (en) * 2008-07-08 2010-01-21 Bart Moutton Guides for an extendable harvesting header
US8122696B2 (en) * 2008-07-08 2012-02-28 Cnh America Llc Guides for an extendable harvesting header
US20120085723A1 (en) * 2010-10-08 2012-04-12 Liebherr-Werk Ehingen Gmbh Boom element, telescopic boom and construction vehicle
US9938121B2 (en) 2011-02-09 2018-04-10 Oshkosh Corporation Crane assembly
US9033165B2 (en) 2011-02-09 2015-05-19 Oshkosh Corporation Crane assembly
US20130020274A1 (en) * 2011-07-21 2013-01-24 Arumugam Munuswamy Tailor welded panel beam for construction machine and method of manufacturing
US9290363B2 (en) * 2011-07-21 2016-03-22 Manitowoc Crane Companies, Llc Tailor welded panel beam for construction machine and method of manufacturing
CN102887443B (en) * 2011-07-21 2016-12-21 马尼托瓦克起重机有限责任公司 Welded plate girder construction machine and a method for producing
CN102887443A (en) * 2011-07-21 2013-01-23 马尼托瓦克起重机有限责任公司 Tailor welded panel beam for construction machine and method of manufacturing
CN103174715A (en) * 2011-12-23 2013-06-26 苏州海伦哲专用车辆有限公司 Telescopic boom sliding block device

Also Published As

Publication number Publication date Type
DE1281651C2 (en) 1975-02-13 grant
GB1122936A (en) 1968-08-07 application
DE1281651B (en) 1975-02-13 application

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