JP2017186116A - Mobile crane and assembling method of mobile crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve working efficiency by performing accurate alignment when a multistage boom is stretched to fit the boom base end part to the boom cylinder mounting portion of an upper revolving body.SOLUTION: Provided is an assembling method of a mobile crane that mounts a boom base end portion of a multistage boom mounted on a boom transportation platform in a manner of capable of rising at a boom mounting portion of an upper swing structure, which comprises both a first positioning step for aligning the positions in the height, the right-left direction, and the front-rear direction and a second positioning step for matching the right-left inclinations of the upper swing body and the multi-stage boom between first and second positioning portions provided on the side of the upper swing body and two positioning members provided opposite to the first and second positioning portions on the side of the base for boom transporting.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a mobile crane and a method for disassembling a mobile crane.

When transporting a mobile crane, it may be transported after being disassembled into an upper swing body and a boom due to transport restrictions. In this case, after the upper swing body and the boom are respectively carried into the work site, the boom is attached to the upper swing body again.
As a method of attaching the boom to the upper swing body, there is a method of lifting and assembling the boom with an auxiliary crane. However, in this method, a large occupied space is required when disassembling and assembling the swing frame and the boom because the auxiliary crane is arranged. Is done.

Then, the following method of attaching a boom to an upper swing body without using an auxiliary crane is known.
A multi-stage boom is mounted on a boom transportation platform such as a trailer. The boom transportation platform is provided with a boom slide portion for adjusting the height of the multistage boom. By supplying hydraulic pressure for boom expansion / contraction to the multistage boom and extending the boom, the base boom of the multistage boom is brought closer to the upper swing body side. By rotating the boom transportation platform and adjusting the boom slide portion, the boom mounting portion of the upper swing body and the base boom of the multistage boom are aligned in the vertical and horizontal directions. Then, the boom mounting portion of the upper swing body and the base end side of the base boom of the multistage boom are assembled so that the multistage boom can be raised and lowered with respect to the upper swing body (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2015-221703

  In the method described in Patent Document 1, it is difficult to position the central axis of the base boom on the central axis of the base boom mounting portion set in the upper swing body before extending the base boom of the multistage boom. The possibility of interfering with other members on the way is very high. For this reason, it was necessary to repeat the extension of the base boom many times, and the work efficiency was low.

  According to one aspect of the present invention, there is provided a mobile crane assembling method for a mobile crane in which a boom base end portion of a multistage boom mounted on a boom transporting base is attached to a boom mounting portion of an upper swing body so that the boom can be raised and lowered. An assembling method comprising first and second positioning portions provided on the upper swing body side, and two-point positioning provided on the boom transport gantry side facing the first and second positioning portions. A first positioning step for adjusting the height, right and left, and front-rear direction positions of the members, and a second positioning step for adjusting left and right inclinations of the upper swing body and the multistage boom.

  ADVANTAGE OF THE INVENTION According to this invention, position alignment with the boom cylinder attaching part of an upper turning body and the boom base end part of the multistage boom mounted in the mount for boom transportation becomes accurate, and it can improve work efficiency.

It is a side view of the mobile crane which shows one embodiment of this invention. It is a side view of the mobile crane from which the multistage boom in FIG. 1 was removed. It is the figure which shows the base end vicinity of a base boom, (a) is the figure which looked at the base boom from the base end side, (b) is the figure which looked at the base end part vicinity of the base boom from the side. It is a side view of a boom head holding structure and its vicinity. It is sectional drawing of a boom slide structure and its vicinity. (A) is a perspective view of a boom support stand, (b) is a VIb-VIb line sectional view of (a). It is sectional drawing of the boom support stand for showing the structure where a guide bar is projected and retracted, (a) shows the state in which the guide bar was accommodated, (b) shows the state which pulled out the guide bar. It is the top view which looked at the upper turning body from the front. (A) is a perspective view of the vicinity of the first and second positioning portions provided on the upper swing body, and (b) and (c) are views of the first and second positioning portions from the front, respectively. It is a figure. (A), (b) is a figure which shows the modification of a 1st, 2nd positioning part. It is a side view which shows the positional relationship of the laser light source provided in the multistage boom, and the upper turning body. It is the figure which looked at FIG. 11 from the upper part. It is a side view which shows the initial process of assembling a multistage boom to a crane main body. FIG. 14 is a side view showing a step subsequent to FIG. 13. FIG. 15 is a side view showing a step subsequent to FIG. 14. FIG. 16 is a side view showing a step subsequent to FIG. 15.

DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a mobile crane and a mobile crane disassembling method according to the present invention will be described with reference to the drawings.
FIG. 1 is a side view of a mobile crane showing an embodiment of the present invention, and FIG. 2 is a side view of the mobile crane from which the multistage boom in FIG. 1 is removed.
The mobile crane 10 includes a crane main body 11 and a multistage boom 4 that can be pivoted in the vertical direction with respect to the crane main body 11, in other words, can be raised and lowered.
In the following description, the front-rear direction, the up-down direction, and the left-right direction (see FIG. 3 and the like) are as illustrated.

  The crane body 11 includes a lower traveling body 1 and an upper revolving body 3 provided on the lower traveling body 1 via a swivel wheel 21 so as to be able to swivel. The upper swing body 3 includes a swing frame 3a. A front drum 5 and a rear drum 6 are mounted on the revolving frame 3a. An operator cab 82 and a building cover 83 are disposed on the left side of the crane body 11. A building cover 84 (see FIG. 8) is arranged on the right side of the crane body 11.

  The lower traveling body 1 includes a jackup 22 (see FIG. 11 and the like) and side frames 23 connected to the left and right sides of the jackup 22. A crawler belt 1 a is attached to the side frame 23.

  A main frame 3b that constitutes a part of the turning frame 3a is provided with a boom mounting portion 31 that pivotally supports the multistage boom 4 so as to be rotatable. The boom mounting portion 31 is provided with a boom pin insertion hole 31a (see FIG. 2) for inserting a boom pin 81 (see FIG. 1). The boom pin 81 is a shaft-like member for pivotally supporting the multistage boom 4 so as to be rotatable at the boom mounting portion 31 of the main frame 3b. Further, a hoisting boom cylinder 7 for raising and lowering the multistage boom 4 is attached to the main frame 3b.

  The multistage boom 4 (hereinafter also simply referred to as “boom”) is a telescopic boom that can be expanded and contracted, and in other words, with respect to the base boom 41 on the base end side, in other words, the base boom 41 on the rear end side. It is a multistage boom of at least two stages of the inner cylinder 45 which is a boom on the distal end side that can be expanded and contracted. That is, the boom 4 is a boom on the base end side of the multistage boom and can extend and contract in the length direction to the base boom 41 on the base end side which is an outermost outer cylinder and the inner peripheral side of the base boom 41. And a plurality of stages of inner cylinders 45 accommodated therein. At the base end of the base boom 41, a boom pin insertion hole 41a (see FIG. 3B) for inserting the boom pin 81 is provided. When the boom pin 81 is inserted into the boom pin insertion hole 31a of the boom attachment portion 31 and the boom pin insertion hole 41a of the base boom 41, as described above, the boom 4 can be pivoted to the upper swing body 3, that is, the shaft can be raised and lowered. Be supported.

  On the lower surface side of the base boom 41, a cylinder rod mounting portion 42 (see FIG. 1) to which a tip 72 (see FIG. 2) of the cylinder rod of the hoisting boom cylinder 7 is mounted is provided. The cylinder rod mounting portion 42 is provided with a pin insertion hole 42a (see FIG. 11 and the like) for inserting the cylinder pin 86.

  A cylinder pin insertion hole 72 a (see FIG. 2) for inserting the cylinder pin 86 is provided at the tip 72 of the cylinder rod of the hoisting boom cylinder 7. The cylinder pin 86 is a shaft-like member for connecting the cylinder rod mounting portion 42 and the cylinder rod of the hoisting boom cylinder 7 and is inserted into the rod insertion hole and the cylinder pin insertion hole 72a as described above.

  A boom head 46 is provided on the inner cylinder 45 located on the most distal side among the plurality of stages of inner cylinders 45. The boom head 46 is provided with sheaves 47 and 48 around which a winding rope (not shown) is wound. A short jib 49 is attached in front of the sheave 47. Each of the sheaves 47 and 48 is pivotally supported on a shaft attached to the boom head 46.

3A and 3B are views showing the vicinity of the base end of the base boom. FIG. 3A is a view of the base boom viewed from the base end side, and FIG. It is the figure which it saw.
As shown in FIG. 3, the base boom 41 has a front surface 411 and a side surface 412 orthogonal to the front surface 411, and has a substantially rectangular cross-sectional shape. Further, the boom 4 includes a hydraulic cylinder 60 for extending and retracting the inner cylinder 45 positioned closest to the base end with respect to the base boom 41, and a hydraulic cylinder (not illustrated) for extending and contracting adjacent inner cylinders 45 to each other. Is provided. To each of these hydraulic cylinders, pressure oil is supplied from the crane body 11 via a hydraulic hose (not shown) in order to extend and contract the boom 4. Therefore, a hydraulic hose connection 61 is provided in the vicinity of the base end of the base boom 41.

  Moreover, in the boom 4 of this Embodiment, the base boom 41 is expanded-contracted at the time of the decomposition | disassembly of the crane main body 11 and the boom 4, and an assembly so that it may mention later. At that time, the hydraulic oil is supplied from the crane main body 11 to the hydraulic cylinder 60 through a hydraulic hose not shown in FIG. Therefore, in the vicinity of the base end of the base boom 41, a connecting portion 62 that connects the above-described hydraulic hose dedicated to disassembly and assembly, which is different from the connecting portion 61 described above, is provided. The connecting portion 62 includes a connecting portion 62 a that supplies pressure oil for extending the hydraulic cylinder 60 and a connecting portion 62 b that supplies pressure oil for retracting the hydraulic cylinder 60.

  In the mobile crane 10 configured as described above, the crane body 11 and the boom 4 are disassembled and transported separately, and reassembled at the work site, due to restrictions on transportation weight and length.

FIG. 4 is a side view of the boom head holding structure and the vicinity thereof.
When the boom 4 is assembled to the crane body 11, the boom 4 is placed on a boom transport base 201 (see FIG. 11 and the like) as described later. At this time, the boom head 46 provided in the innermost cylinder 45 of the boom 4 is held by the boom head holding structure 110.
The boom head holding structure 110 includes a support member 111 and a support bracket 112. Although not shown, a plurality of sheaves 47 are arranged along the longitudinal direction of the shaft member 113 that pivotally supports the sheave 47. The tip of the shaft member 113 protrudes from the left and right of the boom head 46. A pair of support members 111 are arranged on the left and right of the boom head 46. The support member 111 is provided with a recess into which the shaft member 113 is fitted. The boom head 46 is held by the support member 111 by fitting the left and right protrusions of the boom head 46 of the shaft member 113 into the recesses of the support member 111 and sandwiching the boom head 46 from above with the support bracket 112.

FIG. 5 is a cross-sectional view of the boom slide structure and the vicinity thereof.
The boom slide structure 220 includes a lower frame 221, an upper frame 222, and a slide roller 223. The boom slide structure 220 is mounted on the boom support base 210. The boom support base 210 is mounted on a boom transport base 201 such as a trailer having wheels 202.

  A base boom 41 is placed on the slide roller 223. As will be described later, the base boom 41 is extended by pressure oil. At this time, the base boom 41 moves on the slide roller while rolling the slide roller 223. The lower surface of the base boom 41 is provided with an inclined surface that is inclined obliquely upward from the central portion in the left-right direction toward each side surface. The slide roller 223 is attached to the upper frame 222 so that the outer peripheral surface is parallel to the inclined surface of the base boom 41. The lower frame 221, the upper frame 222, and the slide roller 223 are disposed symmetrically as a pair on the left and right. This symmetry plane is at the same position as the center plane of the base boom 41 in the left-right direction. As shown in FIG. 6A, a plurality of boom slide structures 220 are arranged along the front-rear direction.

6A is a perspective view of the boom support base, and FIG. 6B is a cross-sectional view taken along the line VIb-VIb of FIG. 6A. FIG. 7 is a cross-sectional view of the boom support base for showing a structure in which the guide bar is projected and retracted. FIG. 7A shows a state in which the guide bar is accommodated, and FIG. 7B shows that the guide bar is pulled out. Indicates the state.
A guide bar 231 extending in the front-rear direction is accommodated in the boom support base 210 so as to be able to appear and retract. A pair of guide bars 231 are provided in the left-right direction. The pair of guide bars 231 are arranged symmetrically with respect to the center plane in the left-right direction. As illustrated in FIG. 5, the symmetry plane of the pair of guide bars 231 is at the same position as the symmetry plane of the base boom 41 and the boom slide structure 220.

  As shown in FIGS. 7A and 7B, a flange 232 is provided at one end on the front side of the guide bar 231. The boom support base 210 is formed with a plurality of (four in the embodiment) inner walls 233 provided with through holes 233a through which the flanges 232 of the guide bar 231 are inserted. A stopper 234 having a through hole larger than the outer diameter of the guide bar 231 and smaller than the outer diameter of the flange 232 is attached to the two inner walls 233 on the rear side. The stopper 234 can be formed of a resin such as nylon. The stopper 234 can be a bush having a cylindrical portion that fits into the through hole 233a of the inner wall 233. The inner wall 233 may be provided with a through hole 233a female screw, the stopper 234 may be provided with a male screw, and the stopper 234 may be screwed into the inner wall 233. The guide bar 231 can be pulled out from the boom support base 210 by sliding the through holes 233a of the two front inner walls 233 and the through holes of the two stoppers 234 as guide holes. The guide bar 231 is restricted from moving rearward at the position where the collar 232 contacts the second stopper 234 from the rear side.

8 is a plan view of the upper swing body viewed from the front, and FIG. 9A is a perspective view of the vicinity of the first and second positioning portions provided on the upper swing body, and FIG. FIG. 9C is a diagram of the first and second positioning portions as viewed from the front.
FIG. 11 is a side view showing the positional relationship between the laser light source provided in the multistage boom and the upper swing body, and FIG. 12 is a view of FIG. 11 as viewed from above.
A front frame 51 and a side frame 52 are disposed between the cab 82 and the building cover 84 in the left-right direction of the crane body 11. The front frame 51 and the side frame 52 are provided with first and second positioning portions 171 and 172. As shown in FIG. 9A, the first positioning portion 171 includes a name plate 171 a provided on the front frame 51 and a name plate 171 b provided on the side frame 52. As shown in FIG. 9B, a vertical line 131a is marked on the nameplate 171a. As illustrated in FIG. 9C, a horizontal line 131b is marked on the nameplate 171b. An end line 131c is marked on the rear end of the horizontal line 131b. The second positioning portion 172 is the same, and has a name plate 172a provided on the front frame 51 and a name plate 172b (not shown) provided on the side frame 52. A vertical line 132a is marked on the nameplate 172a. A horizontal line 132b (not shown) and an end line 132c (not shown) are marked on the nameplate 172b (not shown).

  The end of the left guide bar 231 is aligned with the end line 131c of the nameplate 171b, the horizontal center line of the guide bar 231 is the vertical line 131a of the nameplate 171a, and the vertical centerline of the guide bar 231 is the nameplate. Align to the horizontal line 131b of 171b. Although not shown, the end portion of the right guide bar 231 is aligned with the end line 132c of the nameplate 172b, and the center line in the left-right direction of the guide bar 231 is the vertical line 132a (not shown) of the nameplate 172a. Further, the vertical center line of the guide bar 231 is aligned with the horizontal line 132b of the nameplate 172b. If it does in this way, the position of the height of the crane main body 11 and the boom 4, the left-right, and the front-back direction will suit.

  As shown in FIG. 8, a rear frame 53 is disposed on the rear side of the crane body 11 and in the vicinity of the boom attachment portion 31 in the front-rear direction. The rear frame 53 is provided with a third positioning portion 173. The third positioning portion 173 is marked with a double circle, for example. The center of the double circle in the left-right direction is coaxial with the boom 4 assembled to the crane body 11, in other words, the center axis in the left-right direction of the base boom 41. The center of the double circle in the vertical direction is the same position as the height of a laser light source 240 (see FIG. 11), which will be described later.

As shown in FIG. 11, a laser light source 240 is attached below the base end side of the boom 4. The laser light source 240 outputs a visible laser beam such as red. The diameter of the laser beam is substantially the same as the diameter of the double circle of the third positioning portion 173.
The direction of the laser beam output from the laser light source 240 coincides with the central axis in the left-right direction of the mounting portion of the base boom 41 in the left-right direction. Moreover, the up-down direction is a horizontal direction. Therefore, in the state where the boom 4 is lying down horizontally, the vertical direction of the laser beam is parallel to the central axis of the base boom 41 in the vertical direction.

  As shown in FIG. 12, the horizontal axis and the vertical axis of each guide bar 231 are positioned at the vertical lines 131a and 132a and the horizontal lines 131b and 132b of the first and second positioning portions 171 and 172, respectively. In the aligned state, the laser beam output from the laser light source 240 is aligned with the third positioning portion 173. Thereby, the shift | offset | difference of the right-and-left inclination of the crane main body 11 and the base boom 41 is eliminated. Therefore, if the base boom 41 is extended, the base end portion of the base boom 41 goes straight to the boom mounting portion 31 of the crane body 11 and interferes with other parts of the crane body 11. Absent.

As the shape of the third positioning portion 173, for example, a pattern other than a double circle such as a cross shape can be adopted.
The first and second positioning portions 171 and 172 can also use other patterns.

FIGS. 10A and 10B are views showing a modification of the first and second positioning portions.
As shown in FIGS. 10A and 10B, the front frame 51 is provided with a positioning portion 271 having a double circle pattern 271a. The side frame 52 is provided with a nameplate 271b. The vertical center line of the nameplate 271b coincides with the vertical center line position of the double circle pattern 271a. An end line 271c is marked on the nameplate 271b.
The end surface of the guide bar 231 is aligned with the end line 271c, and the center axis in the vertical direction of the guide bar 231 is aligned with the vertical center of the double circle pattern 271a. The center axis in the left-right direction of the guide bar 231 is aligned with the center line in the left-right direction of the double circle pattern 271a. Even in this case, alignment similar to that shown in FIG. 9 can be performed.

With reference to FIGS. 13-16, one Embodiment of the assembly method of a mobile crane is described.
A boom 4 is mounted on a boom transportation platform 201 such as a trailer. The boom head 46 of the boom 4 is held by a boom head holding structure 110 mounted on the boom transportation platform 201. Further, the base end side of the base boom 41 of the boom 4 is supported by a plurality of boom slide structures 220 provided on a boom support base 210 mounted on the boom transporting base 201. In this state, the boom transport base 201 travels backward to approach the crane body 11. The crane body 11 is fixed by a jackup 22. As shown in FIG. 12, the jack-up 22 includes four jacks 22a, and the vertical direction, that is, the height position can be adjusted by raising and lowering the jack 22a. This state is illustrated in FIG. In the method for assembling the mobile crane in the present embodiment, since the auxiliary crane is not used, the work area required for the assembly can be a small area as indicated by the dotted line R in FIG.

  11 and 12, the crane main body 11 and the boom transport base 201 are composed of a central axis of the boom 4 mounting portion of the crane main body 11 and the boom 4 mounted on the boom transport base 201. The center axis is assembled in the vertical direction and the horizontal direction. Therefore, the boom transport base 201 moves toward the crane body 11 from a direction in which the center axis of the boom 4 substantially coincides with the center axis of the assembly part of the boom 4 of the crane body 11.

  As illustrated in FIG. 14, the pair of guide bars 231 accommodated in the boom support base 210 are pulled out toward the crane body 11 side. As shown in FIG. 7B, the pair of guide bars 231 has a predetermined length set by pulling out until the collar 232 comes into contact with a stopper 234 attached to the inner wall 233 on the rear side. Thereby, the space | interval of the front-back direction of the boom attaching part 31 of the crane main body 11 and the base end part of the boom 4 is set to predetermined length.

As illustrated in FIG. 15, the boom transportation platform 201 is moved to the crane body 11 side.
The boom transportation platform 201 is configured such that the rear end surface of the guide bar 231 coincides with the end lines 131c and 132c (not shown) of the first and second positioning portions 171 and 172. This alignment is performed by visual inspection of the operator.
The front-rear positioning of the boom mounting portion 31 of the crane body 11 and the base end portion of the boom 4 is performed at a position where the rear end surface of each guide bar 231 of the boom support base 210 is in contact with the front frame 51. You may make it do.

  And while raising / lowering the four jacks 22a of the jackup 22, the crane main body 11 is rotationally driven, the center axis | shaft of the left-right direction and the up-down direction of each guide bar 231 is made into the 1st, 2nd positioning part 171, 172 is aligned with vertical lines 131a and 132a and horizontal lines 131b and 132b. This alignment is performed by visual inspection of the operator.

  Further, a laser beam is output from a laser light source 240 provided on the lower end surface of the base end portion of the boom 4, and the jack 22 a of the jack-up 22 is adjusted so that the projection pattern coincides with the third positioning portion 173. And the crane body 11 is driven to turn. This alignment is also performed visually by the operator.

  When the alignment between the pair of guide bars 231 and the first and second positioning portions 171 and 172 and the alignment between the laser beam and the third positioning portion 173 are completed, the base boom 41 is attached to the crane body 11. It extends toward the boom attachment portion 31. The base boom 41 is extended by connecting a hydraulic hose dedicated for disassembly and assembly to connection portions 62 a and 62 b provided near the base end of the base boom 41. You may make it connect the hydraulic hose of the crane main body 11 to the connection part 61 directly.

  When the base boom 41 is extended, the boom pin insertion hole 41a of the base boom 41 is aligned with the boom pin insertion hole 31a of the boom attachment portion 31, as shown in FIG. Accordingly, the boom pin 81 (see FIG. 1) is inserted in this state. If the position of the boom pin insertion hole 41a of the base boom 41 and the position of the boom pin insertion hole 31a of the boom mounting portion 31 are not exactly aligned only by extending the base boom 41, the position of the boom 22 can be slightly adjusted by the jack 22a of the jackup 22. The boom pin 81 is inserted into the boom pin insertion hole 41a and the boom pin insertion hole 31a of the boom attachment portion 31 by adjusting.

  Thereafter, the pin insertion hole 42a of the cylinder rod mounting portion 42 and the cylinder pin insertion hole 72a at the tip of the cylinder rod of the hoisting boom cylinder 7 are aligned, and the cylinder pin 86 is inserted (see FIG. 1).

  Further, the support bracket 112 of the boom head holding structure 110 is removed from the support member 111. Thereby, the attachment of the boom 4 to the crane main body 11 is completed.

  In order to remove the boom 4 from the crane main body 11, the boom 4 to the crane main body 11 described above can be performed by a procedure reverse to the assembling method. For this reason, description of the procedure of the method of removing the boom 4 from the crane main body 11 is abbreviate | omitted.

According to the one embodiment, the following effects are obtained.
(1) The first and second positioning portions 171 and 172 provided on the front surface of the crane main body 11 and a pair of guide bars 231 provided on the rear side of the boom transportation base 201 are arranged in height, left and right, and front and rear directions. A first positioning step for matching the positions of the crane body 11 and a second positioning step for matching the left and right inclinations of the crane body 11 and the multistage boom 4. For this reason, before extending the base boom 41, the height of the boom attachment part of the crane main body 11 and the boom 4 mounted in the boom transportation mount 201 can be accurately positioned. Thereby, when extending the base boom 41 to the boom attachment part 31, the probability that the base end part of the base boom 41 will interfere with the other site | part of the crane main body 11 can be reduced. As a result, the work efficiency can be improved as compared with the conventional assembly method in which the base boom 41 is repeatedly extended to extend the base boom 41 to the boom mounting portion 31.

(2) The alignment between the laser beam and the third positioning portion 173 is performed at a position closer to the boom mounting portion 31 than the alignment between the first and second positioning portions 171 and 172 and the guide bar 231. For this reason, the accuracy of alignment improves.
(3) Positioning to the third positioning portion 173 is performed using a laser beam. When the alignment with the third positioning portion 173 is performed by the guide bar 231 in the same manner as the alignment with the first and second positioning portions 171 and 172, the length of the guide bar 231 to be pulled out is increased and stored. The structure of the boom transportation platform 201 such as the place and the holding structure becomes complicated, and as a result, the work efficiency is lowered. That is, since the alignment is performed with the laser beam when the distance between the alignment members is long, the working time can be further shortened.

  In the above-described embodiment, the positioning to the third positioning portion 173 is exemplified as a method using a laser beam. However, instead of this method, in the projection projected from above, the central axis of the boom 4 mounted on the boom transportation platform 201 and the central axis of the hoisting boom cylinder 7 provided in the crane body 11 are made to coincide. It can be set as the method of aligning.

  In the said one Embodiment, it illustrated as a method of assembling the boom 4 to the crane main body 11 of the state which does not mount the side frame 23 and the crawler belt 1a to the jackup 22. However, you may make it assemble the boom 4 to the crane main body 11 which attached the side frame 23 and the crawler belt 1a to the jackup 22. FIG.

  The present invention is not limited to the contents shown in the above-described embodiment and modifications. Other embodiments conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 3 Upper turning body 4 Multistage boom 7 Hoisting boom cylinder 10 Mobile crane 31 Boom attachment part 171 1st positioning part 172 2nd positioning part 173 3rd positioning part 201 Boom transportation stand 231 Guide bar (positioning member)
240 Laser light source 271 Positioning unit

Claims (5)

A method for assembling a mobile crane in which a boom base end portion of a multistage boom mounted on a boom transportation platform is mounted on a boom mounting portion of an upper swing body so as to be able to undulate,
Heights of the first and second positioning portions provided on the upper swing body side and the two positioning members provided on the boom transportation platform side facing the first and second positioning portions A first positioning step for aligning positions in the left and right and front and rear directions;
A method for assembling a mobile crane, comprising: a second positioning step for aligning left and right inclinations of the upper swing body and the multistage boom. The method of assembling a mobile crane according to claim 1,
The second positioning step is provided at a position closer to the boom mounting portion than the first and second positioning portions of the upper swing body and the laser light emitted from the laser light source provided on the multistage boom. A method for assembling a mobile crane, the method comprising the step of aligning the third positioning portion formed. The method of assembling a mobile crane according to claim 1,
The upper swing body to which the multistage boom is attached is mounted with a hoisting boom cylinder having a central axis coaxially with the central axis of the boom mounting portion in a projection projected from above.
The method of assembling a mobile crane, wherein the second positioning step includes a step of aligning a central axis of the multistage boom mounted on the boom transportation platform and a central axis of the hoisting boom cylinder. An upper swing body having a boom mounting portion and a multistage boom to which the boom base end portion is mounted to be able to be raised and lowered to the boom mounting portion;
Further, the upper swing body includes first and second alignment portions for aligning the boom base end portion of the multistage boom with the boom mounting portion in height, left and right, and front and rear directions, A mobile crane comprising: the upper swing body and a third positioning portion that matches the left and right inclinations of the multistage boom. The mobile crane according to claim 4,
The third positioning portion is provided at a position closer to the boom mounting portion in the front-rear direction than the first and second two alignment portions,
Furthermore, the mobile crane in which the laser light source for aligning with the said 3rd positioning part is provided in the said multistage boom.

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