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

Definitions

• the present invention relates to a hydraulic crane according to the preamble of claim 1 .
• a hydraulic crane for instance in the form of a lorry crane or forestry crane, often comprises a column , which is rotatable about a vertical axis of rotation , and a crane boom system, which is mounted to the column and which is intended to carry a load in a load suspension point at an outer end of the crane boom system, wherein the crane boom system comprises two or more liftable and lowerable crane booms which form a connection between the load suspension point and the column and which are articulately connected to each other.
• liftable and lowerable crane boom refers to a crane boom which can be pivoted in a vertical plane so as to thereby perform liftings and lowerings of a load carried by the crane.
• hydraulic cylinder for lifting and lowering the crane boom here refers to the hydraulic cylinder which is associated with the liftable and lowerable crane boom and which carries out the pivoting thereof in a vertical plane.
• FIGs 1 -4 A previously known hydraulic crane according to the preamble of claim 1 is illustrated in Figs 1 -4.
• This crane comprises a first crane boom 1 in the form of a so-called inner boom , which is articulately connected to a rotatable column 2 , and a second crane boom 3 in the form of a so-called outer boom, which is telescopically extensible and articulately connected to the inner boom 1 , wherein the inner boom is 1 pivotable in relation to the column 2 by means of a first hydraulic cylinder 4 in the form of a so-called lifting cylinder and the outer boom 3 is pivotable in relation to the inner boom 1 by means of a second hydraulic cylinder 5 in the form of a so-called outer boom cylinder.
• the upper end of the lifting cylinder 4 of the crane illustrated in Figs 1 -4 is connected to the inner boom 1 through a first link 6 and to the column 2 through a second link 7, wherein each one of these links 6, 7 comprises two arms arranged in parallel with each other.
• the first and second links 6, 7 effect an automatic modification of the point of application of the lifting force exerted by the lifting cylinder 4 as the piston rod of the lifting cylinder is extended and they thereby influence the lever arm of the lifting force exerted by the lifting cylinder 4 in such a manner that the lifting moment of the crane becomes more uniform throughout the angular range of the inner boom 1 .
• the previously known crane illustrated in Figs 1 -4 is a foldable knuckle boom crane where the inner and outer booms 1 , 3 are foldable into a compact parking position when the crane is to be transported or stored , as illustrated in Fig 1 .
• the outer boom 3 is first pivoted downwards in relation to the inner boom 1 in order to reduce the angle between the outer and inner booms as much as possible (see Fig 4), whereupon the inner boom 1 is pivoted downwards in relation to the column 2 in order to reduce the angle between the inner boom 1 and the column 2 as much as possible and make the crane assume its final parking position (see Fig 1 ) with the outer boom 3 in an upwardly inclined position at the side of the column 2.
• the crane may subsequently be moved from the parking position to the working position by performing these movements of the inner and outer booms 1 , 3 in the opposite order.
• a hydraulic crane according to the preamble of claim 1 is also previously known from EP 1 580
• the object of the present invention is to achieve a further development of a hydraulic crane of the above-mentioned type so as to provide a hydraulic crane that is improved in at least some aspect. According to the invention , this object is achieved by means of a hydraulic crane having the features defined in claim 1 .
• the hydraulic crane of the present invention comprises:
• a liftable and lowerable first crane boom which is articulately connected to the column so as to be pivotable in relation to the column about an essentially horizontal second axis of rotation ;
• a first hydraulic cylinder for lifting and lowering the first crane boom in relation to the column , the first hydraulic cylinder having a lower end and an opposite upper end , wherein the first hydraulic cylinder at its lower end is articulately connected to the column ;
• a liftable and lowerable second crane boom which is articulately connected to the first crane boom so as to be pivotable in relation to the first crane boom about an essentially horizontal third axis of rotation ;
• a second hydraulic cylinder for lifting and lowering the second crane boom in relation to the first crane boom , the second hydraulic cylinder having an inner end facing the column and an opposite outer end facing the second crane boom;
• first link through which the upper end of the first hydraulic cylinder is connected to the first crane boom, wherein the first link is articulately connected to the upper end of the first hydraulic cylinder by a first joint and articulately connected to the first crane boom by a second joint;
• the inner end of the second hydraulic cylinder is connected to the first crane boom through the above- mentioned first link, wherein the first link is articulately connected to the inner end of the second hydraulic cylinder by a third joint.
• the first link is configured to mechanically guide the third joint in an arcuate path about the second joint when the first crane boom is pivoted about said second axis of rotation under the effect of the first hydraulic cylinder.
• the first link will consequently effect an automatic movement of the inner end of the second hydraulic cylinder in relation to the first crane boom when the first crane boom is pivoted in relation to the column , which will give certain advantages as explained in closer detail in the description following below.
• Fig 1 is a frontal view of a hydraulic crane according to prior art, as seen in a compact parking position
• Fig 2 is a lateral view of the hydraulic crane of Fig 1 , as seen in an erected working position with the outer boom cylinder fully extended ,
• Fig 3 is a lateral view of the hydraulic crane of Fig 1 , as seen in another erected working position ,
• Fig 4 is a frontal view of the hydraulic crane of Fig 1 , as seen in an intermediate position between the parking position illustrated in Fig 1 and the working position illustrated in Fig 2, is a frontal view of a hydraulic crane according to a first embodiment of the present invention , as seen in a compact parking position , is a lateral view of the hydraulic crane of Fig 5, as seen in an erected working position with the outer boom cylinder fully extended , is a planar view from above of the hydraulic crane of Fig 5, as seen in the erected working position illustrated in Fig 6, is a lateral view of the hydraulic crane of Fig 5, as seen in another erected working position , is a frontal view of the hydraulic crane of Fig 5, as seen in an intermediate position between the parking position illustrated in Fig 5 and the working position illustrated in Fig 6, is a detail enlargement of a section from Fig 5, is a detail enlargement of a section from Fig 9, is a frontal view of a hydraulic crane according to a second embodiment of the invention ,
• Fig 14 is a frontal view of the hydraulic crane of Fig 12 , as seen in an intermediate position between the parking position and the working position ,
• Fig 1 5 is a lateral view of a hydraulic crane according to a third embodiment of the invention , as seen in an erected working position , and
• Fig 16 is a lateral view of a hydraulic crane according to a fourth embodiment of the invention , as seen in an erected working position .
• a hydraulic crane 10 according to different embodiments of the present invention is illustrated in Figs 5- 16.
• the crane 10 is for instance a lorry crane or forestry crane.
• the crane 10 is mounted on a frame 1 1 , which for instance may be connected to the chassis of a lorry or a forestry vehicle.
• the frame 1 1 may be provided with adjustable support legs (not shown) for supporting the crane 10.
• the crane 1 0 comprises:
• a liftable and lowerable first crane boom 15 in the following denominated inner boom, which is articulately connected to the column 13 in such a manner that it is pivotable in relation to the column about an essentially horizontal axis of rotation A2;
• first hydraulic cylinder 16 in the following denominated lifting cylinder, for lifting and lowering the inner boom 15 in relation to the column 13;
• the lifting cylinder 1 6 comprises a cylinder part 16a which is articulately connected to the column 13, and a piston which is received in the cylinder part 16a and displaceable in relation to it, wherein the piston is fixed to a piston rod 16b which is articulately connected to the inner boom 15 through a link system 20.
• the outer boom cylinder 18 has an inner end facing the column 13 and an opposite outer end facing the outer boom 1 7.
• the outer boom cylinder 18 comprises a cylinder part 18a which is articulately connected to the inner boom 15 through the link system 20, and a piston which is received in the cylinder part 18a and displaceable in relation to it, wherein the piston is fixed to a piston rod 18b which is articulately connected to the outer boom 1 7.
• the piston rod 18b of the outer boom cylinder is articulately connected directly to the outer boom 17 by a joint 21 provided on the outer boom.
• the piston rod 18b of the outer boom cylinder may be articulately connected to the outer boom 1 7 through a link system 22 of conventional type, as illustrated in Fig 1 5.
• the outer boom 1 7 is telescopically extensible to enable an adjustment of the extension length thereof.
• the outer boom 1 7 comprises a base section 1 7a, through which the outer boom 1 7 is articulately connected to the inner boom 1 5, and several telescopic crane boom sections 1 7b which are carried by the base section 1 7a and displaceable in the longitudinal direction of the base section by means of hydraulic cylinders 23 for adjustment of the extension length of the outer boom 1 7.
• a load handling tool (not shown) is to be mounted to the outer end of the outer boom 1 7.
• the above-mentioned link system 20 at the upper end of the lifting cylinder 16 comprises a first link 24, through which the upper end of the lifting cylinder 16, i .e. in the illustrated example the upper end of the piston rod 16b, is connected to the inner boom 15.
• the first link 24 is articulately connected to the upper end of the lifting cylinder 16 by a first joint J 1 , which forms an essentially horizontal axis of rotation , and articulately connected to the inner boom 15 by a second joint J2, which forms another essentially horizontal axis of rotation that extends in parallel with the axis of rotation formed by said first joint J 1 .
• the first link 24 is articulately connected to the inner end of the outer boom cylinder 18, i .e.
• the first link 24 is arranged to form a connection between the upper end of the lifting cylinder 16, the inner end of the outer boom cylinder 18 and the inner boom 15.
• the lateral walls of the inner boom 15 are illustrated in broken lines in Figs 5-16.
• the inner boom 15 has a U-shaped cross-sectional shape with a downwardly facing opening .
• An upper end of the first link 24 is received in an inner space of the inner boom 15 between the opposite lateral walls of the inner boom, wherein the first link 24 extends through a downwardly facing opening between these lateral walls.
• the link system 20 also comprises a second link 25, which is arranged to form a connection between the upper end of the first hydraulic cylinder 16 and the column 13 or between the first link 24 and the column 13.
• the second link 25 forms a connection between the upper end of the lifting cylinder 16 and the column 13.
• the second link 25 is at a first end articulately connected to the upper end of the lifting cylinder 16 by the above-mentioned first joint J 1 and at an opposite second end articulately connected to the column 13 by another joint J5, which forms an essentially horizontal axis of rotation that extends in parallel with the axis of rotation formed by the first joint J 1 .
• the second link 25 forms a connection between the first link 24 and the column 13.
• the second link 25 is at a first end articulately connected to the first link 24 by a fourth joint J4, which forms an essentially horizontal axis of rotation that extends in parallel with the axis of rotation formed by the first joint J 1 , and at an opposite second end articulately connected to the column 13 by another joint J5, which forms an essentially horizontal axis of rotation that extends in parallel with the axis of rotation formed by the fourth joint J4.
• the fourth joint J4 is located on the first link 24 between the first and second joints J 1 , J2.
• the second link 25 comprises two link elements which are arranged in parallel with each other on opposite sides of the column 13.
• the first link 24 is configured to mechanically guide the third joint J3 in an arcuate path 26 (see Figs 10 and 1 1 ) about the second joint J2 when the inner boom 15 is pivoted in relation to the column 13 about the second axis of rotation A2 under the effect of the lifting cylinder 16.
• the distance between the second axis or rotation A2 and the third joint J3, and thereby also the distance between the second axis or rotation A2 and the inner end of the outer boom cylinder 18 will vary when the piston rod 16b of the lifting cylinder 16 is extended in order to pivot the inner boom 15 upwards in relation to the column 1 3 and when the piston rod 16b of the lifting cylinder is retracted in order to pivot the inner boom 15 downwards in relation to the column 13.
• the crane 10 is a foldable knuckle boom crane, wherein the inner and outer booms 15, 1 7 of the crane are foldable into a compact parking position when the crane is to be transported or stored , as illustrated in Figs 5 and 12.
• the telescopic crane boom sections 1 7b of the outer boom 1 7 are laterally offset in relation to the inner boom 15 and arranged to extend in parallel with and at the side of the inner boom 15, as illustrated in Fig 7.
• the telescopic crane boom sections 1 7b of the outer boom 1 7 are first retracted into the base section 1 7a of the outer boom in order to make the outer boom as short as possible, whereupon the outer boom 1 7 is folded downwards towards the inner boom 15 by retracting the piston rod 18b of the outer boom cylinder 18 as far as possible into the cylinder part 18a of the outer boom cylinder and thereby reducing the angle between the inner and outer booms 15, 1 7, as illustrated in Figs 9 and 14.
• the inner boom 15 is folded downwards together with the outer boom 1 7 towards the frame 1 1 from the intermediate position illustrated in Figs 9 and 14 to the final parking position illustrated in Figs 5 and 12 by retracting the piston rod 16b of the lifting cylinder 16 as far as possible into the cylinder part 16a of the lifting cylinder and thereby reducing the angle between the inner boom 15 and the column 13 as much as possible.
• the inner and outer booms 15, 1 7 are moved in the opposite manner when they are to be moved from the parking position to the erected working position .
• the inner boom 15 is first pivoted upwards in relation to the column 13 about the second axis of rotation A2 by extending the piston rod 16b of the lifting cylinder 16, whereupon the outer boom 1 7 is pivoted upwards in relation to the inner boom 15 about the third axis of rotation A3 by extending the piston rod 18b of the outer boom cylinder 18.
• the third joint J3 is moved downwards and forwards in relation to the inner boom 15, whereby the distance between the second axis of rotation A2 and the third joint J3, and thereby the distance between the second axis of rotation A2 and the inner end of the outer boom cylinder 18, is increased , which in its turn implies that the outer boom 1 7 is automatically made to pivot somewhat upwards in relation to the inner boom 15 about the third axis of rotation A3.
• This automatic pivoting movement of the outer boom 1 7 is achieved without any extension of the piston rod 18b of the outer boom cylinder 18, which consequently will increase the angular range that can be achieved between the inner and outer booms 15, 1 7 by means of an outer boom cylinder 18 having a given length of stroke.
• the crane 10 according to the first embodiment of the invention illustrated in Figs 5-1 1 has exactly the same design as the prior art crane illustrated in Figs 1 -4.
• the outer boom cylinder 18 has the same length of stroke as the outer boom cylinder 5 included in the prior art crane shown in Figs 1 -4
• the inner end of the outer boom cylinder 18 has the same position in relation to the column 13 and the inner boom 15 in the parking position of the crane as the inner end of the outer boom cylinder 5 included in the prior art crane shown in Figs 1 -4
• the joint 21 between the outer end of the outer boom cylinder 18 and the outer boom 17 has the same position on the outer boom as the corresponding joint of the prior art crane shown in Figs 1 -4.
• Fig 2 illustrates the prior art crane with the outer boom cylinder 5 fully extended
• Fig 6 illustrates the crane 10 according to the first embodiment of the invention with the outer boom cylinder 18 fully extended
• the outer boom 3 of the prior art crane is essentially in line with the inner boom 1
• the outer boom 1 7 of the crane 10 according to the first embodiment of the invention is inclined slightly upwards in relation to the inner boom 15.
• Figs 3 and 8 illustrate the prior art crane and the crane 10 according to the first embodiment of the invention in one and the same working position , i .e.
• the position of the joint 21 between the outer end of the outer boom cylinder 18 and the outer boom 1 7 has been slightly altered as compared to the prior art crane illustrated in Figs 1 -4 and as compared to the crane 10 according to the first embodiment illustrated in Figs 5-1 1 .
• the crane 10 according to the second embodiment of the invention illustrated in Figs 12- 14 has exactly the same design as the prior art crane illustrated in Figs 1 -4.
• the outer boom cylinder 18 has the same length of stroke as the outer boom cylinder 5 included in the prior art crane shown in Figs 1 -4, and the inner end of the outer boom cylinder 18 has the same position in relation to the column 13 and the inner boom 15 in the parking position of the crane 10 as the inner end of the outer boom cylinder 5 included in the prior art crane shown in Figs 1 -4.
• This reduced space requirement for the outer boom 1 7 in the parking position makes it possible to increase the length of the outer boom 1 7 without exceeding the maximum allowed width of the crane 10 in the parking position , which in its turn implies that the length of the outer boom 1 7 in its fully extended state, and thereby the range of the crane, can be increased by increasing the length of the base section 1 7a and the telescopic crane boom sections 1 7b and/or by increasing the number of telescopic crane boom sections 1 7b.

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

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• 2016
  • 2016-12-16 EP EP16204799.7A patent/EP3336043B1/en active Active
  • 2016-12-16 DK DK16204799.7T patent/DK3336043T3/da active
• 2017
  • 2017-11-29 WO PCT/EP2017/080739 patent/WO2018108523A1/en not_active Ceased
  • 2017-11-29 CN CN201780077798.1A patent/CN110049940B/zh not_active Expired - Fee Related

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