WO1992004270A1 - Grue a fleche externe - Google Patents

Grue a fleche externe Download PDF

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Publication number
WO1992004270A1
WO1992004270A1 PCT/SE1991/000554 SE9100554W WO9204270A1 WO 1992004270 A1 WO1992004270 A1 WO 1992004270A1 SE 9100554 W SE9100554 W SE 9100554W WO 9204270 A1 WO9204270 A1 WO 9204270A1
Authority
WO
WIPO (PCT)
Prior art keywords
boom
articulation
link
section
boom section
Prior art date
Application number
PCT/SE1991/000554
Other languages
English (en)
Inventor
Hans Nilsson
Original Assignee
Hiab Ab
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 Hiab Ab filed Critical Hiab Ab
Publication of WO1992004270A1 publication Critical patent/WO1992004270A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C23/00—Cranes 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
    • B66C23/54—Cranes 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 with pneumatic or hydraulic motors, e.g. for actuating jib-cranes on tractors
    • B66C23/545—Cranes 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 with pneumatic or hydraulic motors, e.g. for actuating jib-cranes on tractors with arrangements for avoiding dead centre problems during cylinder motion
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C23/00—Cranes 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
    • B66C23/54—Cranes 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 with pneumatic or hydraulic motors, e.g. for actuating jib-cranes on tractors

Definitions

  • This invention relates to an .outer-boom crane of the type including a first boom section and an outer boom con ⁇ nected thereto by a first or main articulation and pivot- able in relation thereto with the aid of a double-acting hydraulic cylinder which is arranged on the upper side of said first boom section and whose one end, e.g. the cylin- der end, is articulated to said first boom section and whose other end, e.g.
  • the piston-rod end is articulated to at least a first link forming part of a link system which operates between said first boom section and said outer boom and which further includes at least a second link articulated to said first link by a second articu ⁇ lation and to the outer boom by a third articulation, said first link being connected to the first boom section by a fourth articulation, said outer boom being pivotable rela ⁇ tive to said first boom section between a first end or starting position on the underside of the first boom sec ⁇ tion and a second end position on the upper side of a longitudinal centre axis through the first boom section, the main outer-boom working range for lifting and lowering a load being located essentially within the semicircle of the pivotal movement closest to said first end position.
  • a double-acting hydraulic cylinder operates either by pulling or by push ⁇ ing action.
  • hydraulic oil is supplied to the chamber located on the piston-rod side, and at the same time oil is evacuated from the other chamber, while the length of the hydraulic cylinder is shortened.
  • a pushing cylinder operates by oil being pumped into the chamber on the piston side, and at the same time oil is evacuated from the chamber on the piston-rod side, while the cylin ⁇ der is lengthened. Since the piston rod takes up a certain amount of space in the associated chamber, the effective pressure area on the piston-rod side is considerably smaller than that on the piston side.
  • the link system serves to enable pivotal movement of the outer boom within a working range exceeding 180°, more precisely between a first end position in which the outer boom is parallel and immediately adjacent to the underside of the first boom section, and an opposite second end position in which it is directed upwardly and forms an angle of about 45° with an imaginary extension of the first boom section, i.e., the outer boom can maximally be pivoted about 225° between the two end positions.
  • the link system between the outer boom and the first boom section there is, in the link system between the outer boom and the first boom section, a comparatively short distance between the main articulation and the fourth articulation connecting the first link to the outer boom, at the same time as both the first and the second link are much longer than this distance.
  • the second link will, when the first link is pivoted by means of the hydraulic cylinder, move in an essentially arcuate path outside of and about the main articulation while trans ⁇ mitting power to the third articulation which is located in essentially the same plane as the main articulation that is perpendicular to the longitudinal axis of the outer boom, the stretch between the main articulation and the third articulation forming the required moment arm for carrying out the pivotal movement.
  • Outer-boom cranes of the type described above are advantageously used in forestry work and are usually mounted on the rear end of a lorry or a trailer. These cranes then include a timber grapple mounted at the tip of the outer boom or a projecting member forming part there ⁇ of, i.e.
  • the grapple may advantageously be set in a position of rest on the load carrier of the vehicle, at the same time as the first boom section can rest on the load carrier, owing to it being possible to set the outer boom in an upwardly directed position where it forms an angle of about 45° with the first boom sec ⁇ tion.
  • Another advantage of these prior-art cranes is that the hydraulic cylinder is mounted in a protected position on the first boom section, so as not to be damaged when the first boom section, as often happens in practice, strikes the upright stakes defining the loading space of the vehicle.
  • the prior-art cranes described also have several disadvantages.
  • the hydraulic cylinder ope ⁇ rates by pulling action within precisely that part of the working range where the power requirement is at its high ⁇ est, i.e. in the sector of more than 90° in which the outer boom is pointing outwards from the tip of the first boom section.
  • the piston rod of the cylinder has to be rather thick for reasons of strength, this means that the cylinder has to be extra ⁇ ordinarily sturdy, and consequently becomes not only expensive but also heavy.
  • the hydraulic system associated with the cylinder is rendered even more com ⁇ plicated and expensive by the necessary arrangement there ⁇ in of so-called lowering control valves. The reason for this is as follows.
  • Prior-art cranes further suffer from the disadvantage of a restricted range of pivotal movement, namely maximally about 225°. Further, the outer boom cannot be parked in a position where it is parallel to and above the first boom section.
  • One object of the present invention is to obviate the drawbacks of prior-art outer-boom cranes by providing a crane in which the hydraulic cylinder can operate by push ⁇ ing action when the power requirement is at a maximum and in which the hydraulic cylinder thus can be given minimum dimensions for a certain requirement.
  • a further object of the invention is to provide a crane in which there is no need of any special lowering control valves.
  • FIG. 1 is a side view showing the crane according to the invention in two different positions
  • FIG. 2 is a simplified top plan view showing the first boom section and the outer boom of the crane in a substantially horizontal extended position
  • FIG. 3 is an enlarged side view of the crane, showing the first boom section in a lowered position and the outer boom in a raised parking position
  • FIG. 4 is a partial side view showing a modified embodi ⁇ ment of the invention.
  • the crane illustrated in Figs 1-3 has a first boom section 1 and an outer boom 2. At its inner end, the first boom section 1 is articulated to a post or body 3 so as to be pivotable in relation thereto by a hydraulic cylinder 4 termed air cylinder.
  • a hydraulic cylinder 4 termed air cylinder.
  • the post 3 may, via a live ring 5, be mounted on a supporting girder 7 which stands on legs 6 and which in turn can be mounted on a vehicle chassis as indicated by frame girders 8, 8'.
  • the live ring 5 or an equivalent device By the live ring 5 or an equivalent device, the post 3 can be turned to different rotational positions relative to the supporting girder 7.
  • the outer boom 2 is connected to the first boom sec ⁇ tion 1 by a first or main articulation 9 and can be pivot ⁇ ed relative to the first boom section with the aid of a double-acting hydraulic cylinder 10 termed outer-boom cylinder, which is situated on the upper side of the first boom section.
  • the first boom section 1 is chiefly made up of a box girder 11 whose upper side is designated 11' and whose underside is designated 11", its side flanges being designated 11"' (see Fig. 2).
  • the outer boom 2 is chiefly made up a box girder 12 whose upper side is designated 12' and whose underside is designated 12", its side flanges being designated 12"'.
  • a tool carrier 13 which may be mounted either directly on the outer boom or on an extendable telescopic boom incorporated therein.
  • the tool carrier may carry a rotator from which is suspended a timber grapple. Natural ⁇ ly, the carrier 13 may carry any optional tools.
  • the hydraulic cylinder 10 which in conventional man- ner includes a proper cylinder member 14 and a piston rod
  • the link 16 is part of a link system which operates between the first boom section 1 and the outer boom 2 and further includes a second link 17.
  • the link 17 is con ⁇ nected to the first link 16 by a second articulation 18 and to the outer boom 2 by a third articulation 19.
  • the first link 16 is connected to the first boom section by a fourth articulation 20.
  • the link system further includes a fifth articulation 21 connecting the first link 16 to the hydraulic cylinder 10, more precisely to the piston-rod end thereof.
  • the cylinder member 14 is connected to the first boom section 1 by a sixth articulation 22.
  • the outer boom 2 can be pivoted relative to the first boom section 1 between, on the one hand, a first end or starting position A (indicated by broken lines in Fig.
  • the main outer-boom working range for lifting and lowering a load is located essentially within the semicircle of the pivo ⁇ tal-movement range closest to the first end position A.
  • the terms upper side and underside are used for conceptual simplicity, and these parts of the first boom section and the outer boom are not always situated respectively above and below one another.
  • the outer-boom surface or flange 12" termed underside may be turned upwards in relation to the oppo ⁇ site surface or flange 12' , namely when the outer boom is in the starting position A.
  • the first boom section 1 may also be set in other positions than the substantially horizontal position illustrated in Fig. 1, and strictly speaking the opposite surfaces 11' and 11" thus no longer are the upper side and the underside, respectively.
  • the distance between the third and the fourth articulation 9 and 20 exceeds that between the second and the fourth articulation 18 and 20.
  • the third articulation 19 connecting the second link 17 to the outer boom 2 has been removed from the main articulation 9 and located at least a certain distance out on the outer boom as seen from the main articulation 9. This enables positioning of the second link 17 (or a straight line between the second and the third articulation 18, 19) below the main articulation 9 in order - when the outer boom 2 is within its working range - to pivot the outer boom from the first end or starting position A by lengthening the hydraulic cylinder 10, and to pivot the outer boom in the opposite direction by shortening the hydraulic cylinder.
  • This geometry of the link system makes it possible for the hydraulic cylinder to lift the outer boom by exerting a pulling action in precisely that part or sector of the working range where the power requirement is the highest, namely in the sector where the outer boom is directed-out from the first boom section, as indicated in Fig. 1.
  • the first link 16 is made up of two halves 16', 16" which are rigidly interconnected by a connecting element 23 and are located one on each side of the first boom section.
  • the second link 17 is made up of two halves 17', 17" arranged one on each side of the outer boom and the first boom section, respectively.
  • the connecting element 23 also forms the articulation 21 connecting the link or link halves to the piston rod 15.
  • the element 23 may consist of a pivot on which is mounted a carrier ring 24 disposed at the free end of the piston rod.
  • the first boom section 1 has two spaced-apart side elements 25, 25' which are inclined relative to the longitudinal or centre axis of the first boom section and project a dis ⁇ tance upwards from the upper side of the first boom sec ⁇ tion to position the main articulation 9 away from said longitudinal axis. More precisely, the distance or dif ⁇ ference in level between the main articulation 9 and an imaginary extension of the upper side 11' of the first boom section perpendicular thereto should be substantially equal to the sum of the diameter of the cylinder member 14 and the distance between the upper side 12' of the outer boom and an axis 26 which is parallel thereto and extends through the main articulation 9.
  • the outer boom may, as is apparent from Fig.
  • each of the two side elements 25, 25' may be a sheet metal member of wedge-like tapering shape.
  • the thicker or broader end of the individual wedge- like side member is connected to the first boom section, whereas the narrow end forms an attchment for the main articulation 9.
  • the individual side element may advan ⁇ tageously, as is seen most clearly in Fig.
  • the outer end 29 of the box girder 11 is located at a certain distance inwardly of the main articulation 9 (see Fig. 2), and there is consequently a free space 30 in the area between the articulation 9 and the girder end 29.
  • two reinforcement plates 31, 31' for the articulation 19 can be partially contained in the space 30, more pre- cisely with portions thereof extending downwardly a short distance from the underside 12" of the outer boom.
  • the articulation 19, which in practice may be a throughgoing pivot or tubular member, is positioned at such a distance from the articu- lation 9 that it in the end position A will be located in the transitional area 32 (see Fig. 3) between the bent outer end portions 27 of the side elements 25, 25' and the edges 28.
  • the two articulations 18 and 21 are spaced apart from one another, advantageously a considerable distance along a circular arc whose centre is the articulation 20.
  • the articulation 19 may advan ⁇ tageously be located along the imaginary straight line 33 connecting the main articulation 9 to an attachment centre 13' on the tool carrier 13.
  • the link 17 or link halves 17', 17" act upon the lower half of the outer boom, i.e. below the longitudinal axis 26.
  • the crane described operates as follows.
  • the outer boom In its first end position A, the outer boom forms an angle of about 30° with the first boom section. More pre ⁇ cisely, the connecting line 33 between the main articula ⁇ tion 9 and the attachment centre 13' forms an angle of exactly 28° with the first boom section 1. From this end position, the outer boom is movable within its so-called working range which extends through about 180° from the end position A.
  • the first boom section 1 When the first boom section 1 is set as in Fig. 1, i.e. is directed essentially horizontally out ⁇ wardly from the post 3, a first sector of about 60° is located to the left of a vertical line through the main articulation 9, and a sector of about 120° is situated to the right of the vertical line.
  • the tool carrier 13 When the outer boom is moved from the end position A, the tool carrier 13 thus moves downwards in the left sector of the working range but will, when swung further into the right sector, move upwards.
  • the tool carrier When in the left sector, the tool carrier is located comparatively close to the post 3, for which rea ⁇ son the power required for lifting operations in this sec ⁇ tor is fairly restricted.
  • the distance between the load carrier and the crane post is larger, and the power requirement thus is much higher.
  • the power requirement is at a maximum when the outer boom is directed substantially horizontally out ⁇ wardly from the first boom section.
  • the first link 16 When the outer boom is in the right sector of the working range and the hydraulic cylinder 10 is lengthened by oil supply on the piston side, at the same time as oil is evacuated from the chamber on the piston-rod side, the first link 16 will be pivoted clockwise about the articu ⁇ lation 20, as seen in Fig. 1.
  • this movement is transmitted to the articulation 19 which applies to the outer boom a force' striving to pivot the latter anticlockwise about the main articulation 9.
  • the lifting moment required to pivot the outer boom about the main articulation is determined by the distance or the leverage between the main articulation 9 and the second link or link halves 17', 17" (or more precisely the straight line connecting the articulation 19 to the arti ⁇ culation 18).
  • the hydraulic cylinder may thus operate by pushing action, which, for reasons mentioned in the introduction, is advantageous in so far as the hydraulic cylinder thus can be given minimum dimensions for a given requirement.
  • the power required for lifting a load is so small that it can be fairly provided for despite the fact that the cylinder operates by pulling action when lifting in this sector.
  • the invention makes it possible to park the outer boom in a position on the first boom section, to which it is then parallel and comparatively close, at the same time as the cylinder retains its impact-protected position on the first boom section, more precisely between this section and the outer boom.
  • Fig. 4 shows an alternative embodiment of the inven ⁇ tion, in which the second link (or link halves) 17 are connected to the articulation 21' connecting the piston rod 15 of the hydraulic cylinder to the first link 16.
  • the articulations 18, 21 are replaced by a single common articulation 21' , which naturally simplifies the making of the link system proper, but also slightly impairs the ability of the outer boom to lift a load high up, since the leverage between the main articulation 9 and the second link here is reduced more quickly when the outer boom is swung upwards.
  • the hydraulic cylinder 10 may be so turned that the piston rod is connected to the first boom section and the cylinder member is connected to the link at issue, the embodiment shown being, however, the one preferred.
  • the relationship between the lengths of the first boom section, the outer boom and the crane post can be varied within wide limits, although the embo ⁇ diment shown is preferred, in which the first boom section is longer than the outer boom proper (when the projecting member is not pulled out) and the crane post, the post and the outer boom being of approximately the same length.
  • the crane according to the invention can be mounted in various ways.
  • the outer boom can be parked on the upper side of the first boom section advantageously permits the crane to be mounted between the driver's cab and a load carrier behind the cab, it is conceivable to mount the crane in other optional positions, not only on a vehicle but also elsewhere, e.g. on a ship or a stationary structure.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Jib Cranes (AREA)

Abstract

Une grue à flèche externe comprend une première partie de flèche (1) et une flèche externe (2). La flèche externe peut être pivotée par rapport à la première partie de flèche par l'intermédiaire d'un cylindre hydraulique (10) relié à un sytème d'accouplement fonctionnant entre la première partie de flèche et la flèche externe et comprend au moins un premier élément d'accouplement (16) et un second élément d'accouplement (17), Le système d'accouplement comporte au moins quatre articulations différentes, notamment une première articulation (9), une seconde articulation (18), une troisième articulation (19) et une quatrième articulation (20). De plus, la distance entre la première et la quatrième articulation (9, 20) est supérieure à celle entre la second et la quatrième articulation (18, 20), la troisième articulation (19), reliant le second élément d'accouplement (17) à la flèche externe (2), étant éloignée de la première articulation (9). Le second élément d'accouplement (17) peut alors être placé sous la première ou principale articulation (9) lorsque la flèche externe est dans son rayon de fonctionnement. Ainsi, la flèche externe peut être pivotée à partir d'une première position terminale lorsque le cylindre hydraulique (10) est allongé et dans la direction opposée lorsque le cylindre hydraulique est raccourci. De cette manière, le cylindre hydraulique peut fonctionner par une action de poussée lorsque les besoins de puissance sont à leur maximum.
PCT/SE1991/000554 1990-08-29 1991-08-22 Grue a fleche externe WO1992004270A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9002764-0 1990-08-29
SE9002764A SE466911B (sv) 1990-08-29 1990-08-29 Vipparmskran

Publications (1)

Publication Number Publication Date
WO1992004270A1 true WO1992004270A1 (fr) 1992-03-19

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ID=20380235

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1991/000554 WO1992004270A1 (fr) 1990-08-29 1991-08-22 Grue a fleche externe

Country Status (3)

Country Link
AU (1) AU8494191A (fr)
SE (1) SE466911B (fr)
WO (1) WO1992004270A1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT500873B1 (de) * 2004-02-25 2008-09-15 Stummer Guenter Hydraulische drehvorrichtung
WO2009031131A2 (fr) * 2007-09-07 2009-03-12 Vincent Southall Bras mécanique articulé
CN102887440A (zh) * 2012-11-01 2013-01-23 长沙桑尼重工机械有限公司 多功能智能随车旋挖起重机
EP2789566A1 (fr) * 2013-04-11 2014-10-15 HMF Group A/S Grue pliante
WO2018080403A1 (fr) * 2016-10-25 2018-05-03 Tajfun Liv, Proizvodnja In Razvoj D.O.O. Grue pliable
EP3339237A1 (fr) * 2016-12-20 2018-06-27 Cargotec Patenter AB Grue hydraulique
WO2019009818A1 (fr) * 2017-07-03 2019-01-10 Tajfun Liv, Proizvodnja In Razvoj D.O.O. Grue ou appareil de manipulation similaire avec ensemble intégré pour surmonter chaque position de point de repos entre une partie primaire et une partie secondaire de son bras opérationnel
US12043525B1 (en) 2022-07-06 2024-07-23 Tanner E. Mart Lifting apparatus mountable on a wall

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1572513A (fr) * 1968-05-10 1969-06-27
DE2908472A1 (de) * 1979-03-05 1980-09-11 Weserhuette Ag Eisenwerk Geraet zum ein- und ausbau von bandrollengirlanden
SE456575B (sv) * 1985-04-25 1988-10-17 Hiab Foco Ab Kran vars vipparm er svengbar relativt huvudarmen via ett lenksystem

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1572513A (fr) * 1968-05-10 1969-06-27
DE2908472A1 (de) * 1979-03-05 1980-09-11 Weserhuette Ag Eisenwerk Geraet zum ein- und ausbau von bandrollengirlanden
SE456575B (sv) * 1985-04-25 1988-10-17 Hiab Foco Ab Kran vars vipparm er svengbar relativt huvudarmen via ett lenksystem

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT500873B1 (de) * 2004-02-25 2008-09-15 Stummer Guenter Hydraulische drehvorrichtung
WO2009031131A2 (fr) * 2007-09-07 2009-03-12 Vincent Southall Bras mécanique articulé
WO2009031131A3 (fr) * 2007-09-07 2009-06-25 Vincent Southall Bras mécanique articulé
CN102887440A (zh) * 2012-11-01 2013-01-23 长沙桑尼重工机械有限公司 多功能智能随车旋挖起重机
EP2789566A1 (fr) * 2013-04-11 2014-10-15 HMF Group A/S Grue pliante
WO2018080403A1 (fr) * 2016-10-25 2018-05-03 Tajfun Liv, Proizvodnja In Razvoj D.O.O. Grue pliable
EP3339237A1 (fr) * 2016-12-20 2018-06-27 Cargotec Patenter AB Grue hydraulique
WO2018114250A1 (fr) * 2016-12-20 2018-06-28 Cargotec Patenter Ab Grue hydraulique
WO2019009818A1 (fr) * 2017-07-03 2019-01-10 Tajfun Liv, Proizvodnja In Razvoj D.O.O. Grue ou appareil de manipulation similaire avec ensemble intégré pour surmonter chaque position de point de repos entre une partie primaire et une partie secondaire de son bras opérationnel
RU2752106C1 (ru) * 2017-07-03 2021-07-22 Тайфун Лив, Производнйа Ин Развой Д.О.О. Кран или аналогичный манипуляционный механизм со встроенным узлом для преодоления мертвого положения между первичной и вторичной частями его рабочей стрелы
US11554940B2 (en) 2017-07-03 2023-01-17 Tajfun Liv, Proizvodnja In Razvoj D.O.O. Crane or similar manipulating apparatus with integrated assembly for overcoming each dead position between primary and secondary part of its operational arm
US12043525B1 (en) 2022-07-06 2024-07-23 Tanner E. Mart Lifting apparatus mountable on a wall

Also Published As

Publication number Publication date
SE9002764L (sv) 1992-03-01
SE466911B (sv) 1992-04-27
SE9002764D0 (sv) 1990-08-29
AU8494191A (en) 1992-03-30

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