Crane and method for assembling crane

Abstract

To provide a crane capable of improving assembly workability when being used in any of a first specification and a second specification.SOLUTION: A crane comprises a boom, a mast, and a connection member that connects the mast and the boom, derricking the boom by rotating the mast. The connection member includes a length changing member capable of changing a specification to any specification out of multiple specifications at least including a first specification that connects the mast and the boom using the connection member of a first length and a second specification that connects the mast and the boom using the connection member of a second length. The crane includes a fixing unit for fixing the length changing member when the length changing member is not used.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a crane and a method for assembling a crane. [Background technology]

[0002] Patent document 1 describes a crane that can be changed between a first specification in which the boom is connected to the live mast by a pendant member of a first length, and a second specification in which the boom is connected by a pendant member of a second length that is shorter than the first length. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-154846 A Summary of the Invention [Problem to be solved by the invention]

[0004] With conventional cranes, when using the second specification, some of the pendant parts used with the first specification had to be stored in a separate location from the crane. Therefore, there was room for improvement in the ease of assembly when using the crane with the first specification.

[0005] An object of the present invention is to provide a crane and a method for assembling the crane that can further improve the ease of assembly when used in the first specification and the second specification, respectively. [Means for solving the problem]

[0006] The crane according to the present invention comprises: Boom and Mast and A connecting member that connects the mast and the boom; A crane that raises and lowers the boom by rotating the mast, The connection member is a crane including a length changing member that can be changed to one of a plurality of specifications including at least a first specification in which the mast and the boom are connected by the connection member of a first length and a second specification in which the mast and the boom are connected by the connection member of a second length, The length change member includes a fixing portion for fixing the length change member when the length change member is not in use.

[0007] The method for assembling a crane according to the present invention comprises the steps of: A method for assembling a crane, comprising changing a first specification in which a boom and a mast are connected via a connecting member of a first length to a second specification in which the boom and the mast are connected via a connecting member of a second length, the method comprising the steps of: The length-changing member that was fixed to the fixed part of the crane in the second specification is removed when changing to the first specification, and the boom and the mast are connected by the connecting member including the length-changing member. Effect of the Invention

[0008] According to the present invention, it is possible to obtain an effect of improving the ease of assembly when using a crane in the first specification and in the second specification. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an example of a crane of a first specification according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an example of a crane of a second specification according to the first embodiment of the present invention. [Diagram 3] 1A is a side view showing the lower boom and the length changing member, and FIG. 1B is a front view showing the rotating side end of the lower boom as viewed from the rotating side. [Figure 4] FIG. 2 is a diagram showing assembly steps 1 to 3 of a first specification for the crane of the first embodiment. [Diagram 5] FIG. 11 is a diagram showing assembly steps 4 to 6 of a first specification for the crane of the first embodiment. [Figure 6] FIG. 11 is a diagram showing assembly steps 7 to 9 of a first specification for the crane of the first embodiment. [Figure 7] FIG. 4 is a diagram showing assembly steps 1 to 4 of a second specification for the crane of the first embodiment. [Figure 8] FIG. 11 is a diagram showing assembly steps 5 to 7 of the second specification for the crane of the embodiment 1. [Figure 9] FIG. 2 is a diagram showing the configuration of a control system for a crane in the first embodiment. [Figure 10] FIG. 11 is a side view showing a lower boom and a length changing member of the second embodiment. [Figure 11] FIG. 11 is a diagram showing assembly steps 1 to 3 of a first specification for a crane of embodiment 2. [Figure 12] FIG. 11 is a diagram showing assembly steps 4 to 7 of a first specification for a crane of the second embodiment. [Figure 13] 11 is a diagram showing assembly steps 6 and 7 of a second specification in the crane of the second embodiment. FIG. [Figure 14] FIG. 11 is a side view showing a lower boom and a length changing member of a third embodiment. [Figure 15] FIG. 11 is a diagram showing assembly steps 1 to 4 of a first specification for a crane of a third embodiment. [Figure 16] FIG. 11 is a diagram showing assembly steps 5 to 7 of a first specification for the crane of the third embodiment. [Figure 17] FIG. 11 is a diagram showing an assembly process 7 of the second specification for the crane of the embodiment 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0011] (Embodiment 1) Fig. 1 is a diagram showing an example of a crane of a first specification according to the first embodiment of the present invention. Fig. 2 is a diagram showing an example of a crane of a second specification according to the first embodiment of the present invention.

[0012] The crane 1 of the first embodiment is a crane that can be changed to a plurality of specifications, including a first specification (e.g., crane specification) shown in Fig. 1 and a second specification (e.g., tower specification) shown in Fig. 2.

[0013] The first specification, as shown in Fig. 1, is a configuration in which a hook 10 is suspended from the tip of a boom 4. The second specification, as shown in Fig. 2, is a configuration in which a hook 10 is suspended from the tip of a jib 5 connected to a boom 4.

[0014] The boom 4 is configured so as to be disassembled and assembled into a plurality of elements. The plurality of elements include a lower boom 41, an upper boom 42, and a extension boom 43 (see FIG. 2). The length of the boom 4 can be changed by changing the number of extension booms 43. In the first specification of FIG. 1, the boom 4 is connected to the lower boom 41 and the upper boom 42, but one or more extension booms 43 may be connected between the lower boom 41 and the upper boom 42 in the first specification as well. In the second specification, the boom 4 is configured from the lower boom 41 and a plurality of extension booms 43, and the jib 5 is rotatably connected to the extension boom 43 at one end.

[0015] The lower boom 41 is an element that is rotatably connected to the upper rotating body 3 among the disassemblable elements of the boom 4, and corresponds to elements inclined relative to each other in a direction in which the distance between the upper main member 411 and the lower main member 412 increases as the distance from the center of rotation of the boom 4 increases. The upper main member 411 is a main member that is located at the top when the lower boom 41 is laid down, and extends away from the center of rotation. The lower main member 412 is a main member that is located at the bottom when the lower boom 41 is laid down, and extends away from the center of rotation. That is, the lower boom 41 is composed of four main members and diagonal members between the main members, and the two upper main members when the lower boom 41 is laid down correspond to the upper main member 411, and the two lower main members correspond to the lower main member 412.

[0016] As shown in Fig. 1 and Fig. 2, the crane 1 of the first embodiment includes a travelable lower traveling body 2, an upper rotating body 3 rotatably provided with respect to the lower traveling body 2, a boom 4 connected to the upper rotating body 3 so as to be rotatable in a hoisting direction, a live mast 6 supporting the boom 4, a connection member 20 connecting the live mast 6 and the boom 4, a winch (not shown) for winding or unwinding the wire ropes W1 to W3, and a counterweight 9 mounted on the rear of the upper rotating body 3. A cab 8 for an operator to operate the crane is mounted on the upper rotating body 3. The second specification crane 1 further includes a jib 5 connected to the boom 4 so as to be hoistable, and a strut 7 for supporting the jib 5. The live mast 6 corresponds to an example of a mast according to the present invention.

[0017] The live mast 6 is rotatably connected to the upper rotating body 3, and supports the boom 4 via a connecting member 20. The live mast 6 is supported by a wire rope W1, and the wire rope W1 is wound around a winch.

[0018] In both the first and second specifications, the winch drives the wire rope W1 to wind or pay out, thereby changing the hoisting angle of the live mast 6. As the hoisting angle of the live mast 6 changes, the rotation of the live mast 6 is transmitted to the boom 4 via the connection member 20, thereby changing the hoisting angle of the boom 4. Furthermore, in the first and second specifications, the winch winds or pays out the wire rope W3, thereby raising or lowering the hook 10. In the second specification, the winch winds or pays out the wire rope W2, thereby raising or lowering the jib 5.

[0019] <Connection parts> The connecting member 20 is a member that connects the live mast 6 and the boom 4. The connecting member 20 may be called a pendant member. The connecting member 20 is rod-shaped, long plate-shaped, rope-shaped, or a combination of these, and is mainly made of metal.

[0020] The connection member 20 has a main connection member 21 and a length changing member 22, which are connected together when used.

[0021] The main connection member 21 may be a single member or may include multiple connecting members 21a-21c (see FIG. 2) that can be separated and connected. The main connection member 21 has a length corresponding to the elements of the boom 4 excluding the lower boom 41 (one or more extension booms 43, the upper boom 42, etc.).

[0022] The length changing member 22 includes a basic length changing member 221 and an additional length changing member 222. In the first specification, the basic length changing member 221 and the additional length changing member 222 are joined together when used. In the second specification, the basic length changing member 221 is used, and the additional length changing member 222 is not used. With this configuration, the overall length of the length changing member 22 in the first specification is longer than the overall length of the length changing member 22 in the second specification. By appropriately selecting the length of the length changing member 22, the live mast 6 can be tilted at an appropriate angle during loading and unloading work to operate the crane 1.

[0023] When assembling the crane 1 and the boom 4 at a work site, a worker joins the main connection member 21 and the length changing member 22 to form a continuous connection member 20. The connection member 20 is a set of two pieces, but it may be a single piece or three or more pieces.

[0024] Before assembling the boom 4, the main connecting member 21 is stored in the extension boom 43 or the upper boom 42 by being fixed to the upper part of the extension boom 43 or the upper boom 42 (the upper part when in a reclined position).

[0025] Before assembling the boom 4, the additional length change member 222 of the length change member 22 is stored in the crane 1 by being fixed to the crane 1. Before assembling the boom 4, the basic length change member 221 of the length change member 22 is used to support the lower boom 41.

[0026] <Boom assembly process> Next, the assembly process of the boom 4 will be described. Fig. 3 is a side view (A) showing the lower boom and the length changing member, and a front view (B) of the rotating end of the lower boom as viewed from the rotating side. Figs. 4(A)-(C), 5(A)-(C), and 6(A)-(C) are diagrams showing assembly processes 1-9 of the first specification for the crane of embodiment 1, respectively.

[0027] 4(A) shows the transport posture of the crane 1. The transport posture refers to the posture when the crane 1 is placed on a trailer and transported from another location to a work site, or when it is transported from a work site to another location. In the transport posture of the crane 1, the lower boom 41 is connected to the upper rotating body 3, and the extension boom 43 and the upper boom 42 are separated from the crane 1.

[0028] <Support structure of the lower boom 41 in the transport position> In the transportation posture of the crane 1, the lower boom 41 is supported by the live mast 6 via the basic length changing member 221 in a state where it is floating above the ground and lying down.

[0029] More specifically, a connection part 61 to which one end of the basic length change member 221 is connected is provided at the tip of the live mast 6. A connection part 33 connectable to the other end of the basic length change member 221 is provided at the rotation side end part 41a of the lower boom 41. The rotation side means the side opposite to the rotation center. The rotation side end part 41a means the end part on the rotation side. In the transport posture, one end of the basic length change member 221 is connected to the connection part 61 of the live mast 6, and the other end is connected to the connection part 33 of the lower boom 41, so that the live mast 6 supports the lower boom 41 via the basic length change member 221. The connection between the basic length change member 221 and the connection part 33 is not particularly limited, but a pin connection can be used.

[0030] As shown in FIG. 3B, the connection portion 33 of the lower boom 41 is located within the frame of the pivot side end 41a when the pivot side end 41a of the lower boom 41 is viewed toward the pivot center. Furthermore, the connection portion 33 is provided so as not to protrude toward the pivot side from the joint portion 414 of the lower boom 41 when the lower boom 41 is viewed from the side. The joint portion 414 is also called a connect lug. The joint portion 414 is a portion that connects the lower boom 41 and the upper boom 42, or a portion that connects the lower boom 41 and the joint boom 43. For example, when the pivot side end 41a of the lower boom 41 is viewed toward the pivot center, the joint portion 414 is located at the four corners of the pivot side end 41a and is provided so as to protrude from the pivot side end 41a toward the pivot side. The joint portion 414 is configured so as to be connectable to a joint portion 424 of the upper boom 42 (see FIG. 6A) or a joint portion 434 of the extension boom (see FIG. 6A) by a pin connection.

[0031] More specifically, the connection portion 33 is a bracket having a hole for inserting a pin, and is connected to a frame material or a reinforcing material of the lower boom 41 by welding or via a connecting member such as a bolt.

[0032] <Storage Structure of Additional Length-Adjusting Member 222 in Transportation Posture> The crane 1 is provided with fixing parts 31, 32 for fixing the additional length adjustable member 222. In the transport posture, the additional length adjustable member 222 is stored in the crane 1 by being fixed to the fixing parts 31, 32. The fixing parts 31, 32 are configured to be capable of fixing one end and the other end of the additional length adjustable member 222, respectively. As the fixing structure, a structure in which fixing is performed by a pin connection may be adopted.

[0033] The fixing parts 31 and 32 are disposed on the extension boom side of the lower boom 41. The extension boom side of the lower boom 41 corresponds to the side opposite to the upper rotating body of the crane 1 (i.e., the side farther from the upper rotating body 3) and also corresponds to the tip side of the boom 4 (the side closer to the tip of the boom 4). Hereinafter, the extension boom side of the lower boom 41 is also referred to as the rotating side end 41a of the lower boom 41. The fixing parts 31 and 32 fix the additional length change member 222 so that the longitudinal direction A1 (see FIG. 4(B)) of the fixed additional length change member 222 is within a range B1 of 45 degrees from the vertical direction when the lower boom 41 is in a grounded state. By providing the fixing parts 31 and 32 in this manner, the workability of connecting the basic length change member 221 and the additional length change member 222 can be improved when the additional length change member 222 is used in the assembling process of the boom 4. Because the additional length changing member 222 is heavy, it requires a lot of effort for an operator to translate and rotate the additional length changing member 222. However, by providing the fixing parts 31 and 32 as described above, the additional length changing member 222 can be connected to the basic length changing member 221 and detached from the fixing parts 31 and 32 with only a small translational movement and a small rotational movement from the fixed state. Therefore, the workability of connecting the additional length changing member 222 can be improved.

[0034] The state where the lower boom 41 is on the ground means a state where the crane 1 is placed on a horizontal plane and the tip side of the lower boom 41 is on the plane without a sleeper or the like. In addition, when the tip of the lower boom 41 is not placed on the plane first when the lower boom 41 is rotated around the base end as shown in Fig. 4(B) but other parts are placed on the plane, it means a state where the part of the tip side of the lower boom 41 that is to be placed on the plane first when the lower boom 41 is rotated around the base end is placed on the plane. Fig. 4(B) described later shows a state where the lower boom 41 is on the ground via a sleeper as in actual work.

[0035] As shown in FIG. 3B, the fixing parts 31 and 32 are provided within the frame of the rotating end 41a of the lower boom 41 when the rotating end 41a of the lower boom 41 is viewed toward the center of rotation. The fixing parts 31 and 32 are further provided on the rotation center side of the lower boom 41 than the tip of the joint part 414 of the lower boom 41 when the lower boom 41 is viewed from the side. By disposing the fixing parts 31 and 32 as described above, even if the upper boom 42 or the extension boom 43 is connected to the lower boom 41 with the additional length changing member 222 fixed to the lower boom 41, it is possible to prevent the additional length changing member 222 from interfering with the upper boom 42 or the extension boom 43. Furthermore, it is possible to prevent the overall length or width of the crane 1 in the transport posture from being changed depending on the presence or absence of the additional length changing member 222 and the presence or absence of the fixing parts 31 and 32.

[0036] More specifically, the fixing parts 31, 32 are brackets having holes for inserting pins, and are connected to the frame material or reinforcing material of the lower boom 41 by welding or via connecting members such as bolts.

[0037] <Assembly process of the first specification boom> When assembling the crane 1 in accordance with the first specification, first, a worker lays the live mast 6 further down from the transportation posture at the assembly site to bring the tip side of the lower boom 41 into contact with the ground (FIG. 4(B)). The grounding may be via a sleeper or the like. Next, the worker releases the connection between one end of the basic length change member 221 and the lower boom 41 (FIG. 4(C)). Next, the worker rotates the live mast 6 to slightly raise the basic length change member 221, releases the connection between the upper end of the additional length change member 222 and the fixed part 31, and connects the upper end to the lower end of the basic length change member 221 (FIG. 5(A)). An example of the release of the connection is removing a pin from a pin connection, and an example of the connection is inserting a pin to perform a pin connection. The same applies below.

[0038] Next, the worker disconnects the lower end of the additional length-adjusting member 222 from the fixed portion 32 (Figure 5(B)), and raises the live mast 6 to connect the lower end of the additional length-adjusting member 222 to the upper connection portion 416 of the lower boom 41 (Figure 5(C)).

[0039] Then, the worker carries in the remainder of the boom 4 (the extension boom 43 and the upper boom 42 in FIG. 6(A)) and connects the upper joint portion 434 of the remaining boom 4 to the upper joint portion 414 of the lower boom 41 (FIG. 6(A)). After that, the worker rotates the live mast 6 so as to raise it, thereby aligning the positions of the lower joint portion 434 of the remaining boom 4 and the lower joint portion 414 of the lower boom 41, and connects them (FIG. 6(B)). Next, the worker releases the connection between the lower end portion of the additional length changing member 222 and the lower boom 41, and connects the lower end portion to one end portion of the main connecting member 21 (FIG. 6(C)).

[0040] The main connection member 21 is disposed above the extension boom 43 and the upper boom 42 in the reclined state, and the other end of the main connection member 21 is connected to one end of the upper boom 42. When the main connection member 21 is separated into multiple linking members 21a, 21b and disposed above each extension boom 43 and above the upper boom 42, an operator connects one ends of the multiple linking members 21a, 21b together. As a result, the length changing member 22 and the main connection member 21 are connected to form a set of connection members 20.

[0041] Through the above assembly process, the lower boom 41, the extension boom 43 and the upper boom 42 are connected to form the boom 4. Furthermore, the boom 4 and the live mast 6 are connected via the connecting member 20. As a result, the boom 4 is raised and lowered by the rotation of the live mast 6, making it possible to use the crane 1 in the first specification.

[0042] When returning the crane 1 from the first specification usage state to the transportation attitude, the above assembly steps can be carried out in reverse order.

[0043] <Assembly process of the second specification boom> 7(A) to (D) and 8(A) to (C) are diagrams showing assembly steps 1 to 7 of the second specification for the crane of embodiment 1. Here, an example is shown in which the crane specification shown in Fig. 1 is assembled to the second specification without using the additional length adjusting member 222, instead of the tower specification shown in Fig. 2.

[0044] When using the crane 1 in the second specification, as shown in Figures 7(A) to (C), similar to Figures 4(A) to (C), the worker grounds the lower boom 41 from the transport posture of the crane 1 and removes the basic length changing member 221 from the connection part 33 of the lower boom 41.

[0045] After removing the basic length changing member 221, the worker then raises the basic length changing member 221 by rotating the live mast 6, and connects the lower end of the basic length changing member 221 to the upper connection part 416 of the lower boom 41 (Figure 7 (D)).

[0046] Then, the worker carries in the remainder of the boom 4 (the extension boom 43 and the upper boom 42 in FIG. 8(A)) and connects the upper joint part 434 of the remaining boom 4 to the upper joint part 414 of the lower boom 41 (FIG. 8(A)). After that, the worker rotates the live mast 6 so as to raise it, aligning the positions of the lower joint part 434 of the remaining boom 4 and the lower joint part 414 of the lower boom 41, and connects them (FIG. 8(B)).

[0047] Next, the worker releases the connection between the lower end of the basic length changing member 221 and the upper connection part 416 of the lower boom 41, and connects the lower end to one end of the main connection member 21 (FIG. 8(C)). The main connection member 21 is disposed on the upper side of the extension boom 43 and the upper boom 42 in the reclined state, and the other end of the main connection member 21 is connected to one end of the upper boom 42. When the main connection member 21 is separated into a plurality of connecting members 21a, 21b and disposed on the upper side of each extension boom 43 and on the upper side of the upper boom 42, the worker connects one ends of the plurality of connecting members 21a, 21b to each other. As a result, the length changing member 22 and the main connection member 21 are connected to form a set of connecting members 20.

[0048] Through the above assembly process, the lower boom 41, the extension boom 43 and the upper boom 42 are connected to form the boom 4. Furthermore, the boom 4 and the live mast 6 are connected via the connecting member 20. As a result, the boom 4 is raised and lowered by the rotation of the live mast 6, making it possible to use the crane 1 in the second specification.

[0049] Since the additional length-adjusting member 222 is not used, the overall length of the connecting member 20 is shorter than that of the first specification, and even if the boom 4 is used at the same hoisting angle, the live mast 6 can be prevented from projecting rearward as much as in the first specification. In other words, the rear radius of the crane 1 can be made smaller.

[0050] When returning the crane 1 from the second specification usage state to the transportation attitude, the above assembly steps can be carried out in reverse order.

[0051] As described above, the crane 1 of the first embodiment includes the boom 4, the live mast 6 that raises and lowers the boom 4, and the connection member 20 that connects the live mast 6 and the boom 4. The connection member 20 includes a length change member 22 that can be changed to one of a plurality of specifications including at least a first specification in which the live mast 6 and the boom 4 are connected by a connection member 20 of a first length and a second specification in which the live mast 6 and the boom 4 are connected by a connection member 20 of a second length different from the first length, and includes fixing parts 31 and 32 that fix the length change member 22 (specifically, the additional length change member 222) when the length change member 22 is not used. A length shorter than the first length may be adopted as the second length. Also, a length longer than the first length may be adopted as the second length. Also, the first length and the second length may be equal overall regardless of whether the additional length change member 222 is used or not. Therefore, when transporting the crane 1, there is no need to transport the length changing members 22 separately from the crane 1, and when storing the crane 1, there is no need to store the length changing members 22 separately from the crane 1, improving the workability during transportation and storage. Furthermore, when assembling the crane 1 using all of the length changing members 22, there is no need to transport the length changing members 22 from a location distant from the crane 1 to the crane 1, improving the workability of assembling the crane 1.

[0052] Furthermore, the crane 1 of the first embodiment includes the upper rotating body 3 and the lower boom 41 connected to the upper rotating body 3, and the fixing parts 31, 32 are provided on the lower boom 41. In the assembly process of the crane 1, it is convenient if the installation of the length changing member 22 can be performed near the lower boom 41, since this does not require a large movement of the live mast 6. Therefore, by arranging the fixing parts 31, 32 as described above, the workability of installing the length changing member 22 can be further improved.

[0053] Furthermore, according to the crane 1 of the first embodiment, the fixing parts 31, 32 fix the length change member 22 in a position in which the longitudinal direction A1 of the length change member 22 (specifically, the additional length change member 222) is oriented at an angle of 45 degrees or less from the vertical when the lower boom 41 is in a grounded state. The above angle may be more preferably 30 degrees or less, and even more preferably 15 degrees or less. When the length change member 22 is assembled, the length change member 22 is hung vertically from the tip of the live mast 6. Therefore, since the length change member 22 is fixed as described above, the amount of rotational movement of the length change member 22 can be reduced when assembling the length change member 22. The length change member 22 has a large weight. Since the amount of rotational movement can be reduced as described above, the labor required for assembling the length change member 22 is reduced, and the workability of assembling the crane 1 can be improved.

[0054] Furthermore, according to the crane 1 of the first embodiment, the length changing member 22 has a basic length changing member 221 that is used in both the first specification and the second specification, and an additional length changing member 222 that is used in the first specification but not in the second specification. When the connection member 20 is configured to the second specification, the fixing parts 31, 32 fix the additional length changing member 222. Therefore, even when the additional length changing member 222 is not used, it is not necessary to store the additional length changing member 222 in a location different from the crane 1. This improves the workability of storing the length changing member 22.

[0055] More specifically, according to the crane 1 of the first embodiment, it is possible to connect the extension boom 43 or the upper boom 42 to the lower boom 41 with the additional length adjusting member 222 fixed to the fixing parts 31, 32. Therefore, when using the crane 1 in the second specification, the additional length adjusting member 222 can remain fixed to the fixing parts 31, 32 of the lower boom 41.

[0056] Furthermore, according to the crane 1 of the first embodiment, the fixing parts 31, 32 fix the additional length changing member 222 at a position lower than the upper main member 411 of the lower boom 41 when the lower boom 41 is in a reclined state. According to this configuration, the additional length changing member 222 is disposed at a height that can be handled by an operator from the ground when the lower boom 41 is in a grounded state. Therefore, when assembling the additional length changing member 222 or fixing it to the fixing parts 31, 32, an operator can work from the ground, improving workability. In addition, since the length changing member 22 is fixed while avoiding the upper part of the lower boom 41, the upper part of the lower boom 41 is less likely to become crowded with parts, improving workability when an operator walks on the lower boom 41.

[0057] Furthermore, according to the crane 1 of the first embodiment, the crane 1 can be transported in a state in which the live mast 6 supports the lower boom 41 via the basic length change member 221. Therefore, when transporting or storing the crane 1, it is not necessary to transport the basic length change member 221 separately from the crane 1 or to store it in a location separate from the crane 1. This improves the ease of handling the basic length change member 221. Also, since the crane 1 can be transported in a state in which the basic length change member 221 is connected to the live mast 6, it is possible to save the effort of connecting the basic length change member 221 to the live mast 6 when assembling the crane 1. Also, it is possible to save the effort of providing a separate structure for supporting the lower boom 41 during transportation.

[0058] <Confirmation of specifications for connection parts> FIG. 9 is a diagram showing the configuration of a control system of the crane in the first embodiment.

[0059] As shown in Fig. 9, the crane 1 is equipped with a determination unit 50 that determines whether the connecting member 20 is of the first specification or the second specification. The determination unit 50 is a computer, and is mounted on the crane 1. The specifications of the connecting member 20 when the crane 1 is operated are input to the determination unit 50 by an operator. The determination unit 50 may determine the operating range of each part (the boom 4, the live mast 6, the rotating drive part of the upper rotating body 3, etc.) according to the specifications of the connecting member 20, and control each part so that it does not exceed the operating range.

[0060] The determination unit 50 performs a process (called a "first determination process") to determine whether the specifications of the connecting member 20 input by the worker match the actual specifications. For the first determination process, sensors 51, 52 are provided to detect whether the additional length changing member 222 is fixed to the fixing parts 31, 32 of the lower boom 41 or around them. The sensors 51, 52 send detection outputs to the determination unit 50.

[0061] The first judgment process is executed, for example, at the stage of completing the assembly of the crane 1. In the first judgment process, the judgment unit 50 judges whether or not a length-changing member 22 conforming to the specifications is used based on the detection output of the sensors 51 and 52 and the inputted specification information. Then, when the first specification is inputted and the sensors 51 and 52 detect the additional length-changing member 222, or when the second specification is inputted and the sensors 51 and 52 do not detect the additional length-changing member 222, the judgment unit 50 executes a warning process to inform the worker that the specifications are not conformed. On the other hand, when the first specification is inputted and the sensors 51 and 52 do not detect the additional length-changing member 222, or when the second specification is inputted and the sensors 51 and 52 detect the additional length-changing member 222, the judgment unit 50 judges that the specifications are conformed and does not execute the warning process or executes a process to inform the worker that the specifications are conformed.

[0062] Furthermore, when the crane 1 starts to be used, the determination unit 50 performs a process (referred to as the "second determination process") to determine whether the length of the connection member 20 complies with the specifications. In the second determination process, the determination unit 50 determines whether the relationship between the hoisting angles complies with the specifications of the connection member 20 based on the hoisting angle of the live mast 6 and the hoisting angle of the boom 4. The hoisting angles of the live mast 6 and the boom 4 are measured by angle meters 53 and 54, and the measured values ​​are sent to the determination unit 50. Since the relationship between the above two hoisting angles differs depending on whether the additional length change member 222 is used or not, the determination unit 50 determines whether the additional length change member 222 is used or not as per the specifications from the relationship. If the determination result indicates that the specifications are not met, the determination unit 50 performs a warning process.

[0063] The determination unit 50 may perform the second determination process based on electrical detection via the harness 56. The harness 56 is provided along the connection member 20, and when at least the additional length change member 222 is used, the worker performs the assembly work so that the harness 57 provided along the additional length change member 222 and the harness 56 extending to the determination unit 50 are connected by connectors. The additional length change member 222 has a circuit (resistance circuit or short circuit, etc.) 58 having a specific electrical characteristic, and the circuit 58 is connected to the harness 57. If it is a resistance circuit, the resistance value changes from the total electrical resistance of the harnesses 56 and 57 by connecting the circuit 58. If it is a short circuit, the connection of the circuit 58 changes the open circuit to a closed circuit. The determination unit 50 determines whether the circuit 58 is connected to the harness 57 based on the detection of an electrical variable (current, voltage, resistance, etc.) via the harness 56, and determines whether the additional length change member 222 is used. If the result of the determination is not according to the specifications, the determination unit 50 performs a warning process.

[0064] As described above, according to the crane 1 of this embodiment, the judgment unit 50 judges whether the connection member 20 is of the first specification or the second specification based on whether the additional length change member 222 is fixed to the fixing parts 31, 32. Therefore, the worker can check whether the connection member 20 is according to the specifications at an early stage based on the result of the judgment by the judgment unit 50. Also, even if the additional length change member 222 is not fixed to the fixing parts 31, 32, it does not necessarily mean that the additional length change member 222 is added to the connection member 20. Therefore, by the judgment unit 50 performing the above-mentioned second judgment process, the worker can more accurately check whether the connection member 20 is according to the specifications.

[0065] (Embodiment 2) A crane 1A according to a second embodiment of the present invention is similar to that of the first embodiment except for the configuration of a length adjusting member 22A and the method of using the same. Fig. 10 is a side view showing the lower boom and the length adjusting member of the second embodiment. Figs. 11(A)-(C) and 12(A)-(D) are diagrams showing assembly steps 1-7 of the first specification for the crane of the second embodiment.

[0066] 10, the length changing member 22A has a first member 223 and a second member 224, and one end 223a of the first member 223 is configured to be slidable in the longitudinal direction of the second member 224. Furthermore, one end 224a of the second member 224 is connected to the live mast 6, while the other end 224b of the second member 224 is configured to be fixable to the other end 223b of the first member 223. The fixation is not particularly limited, but a configuration realized by pin connection can be adopted.

[0067] According to the length changing member 22A having this configuration, the other end 223b of the first member 223 and the other end 224b of the second member 224 are fixed by a pin connection, thereby shortening the length changing member 22A. On the other hand, the length changing member 22A can be lengthened by releasing the connection between the other end 223b of the first member 223 and the other end 224b of the second member 224 and sliding the first member 223 relative to the second member 224.

[0068] The other end 223b of the first member 223 has two connection parts (specifically, pin holes) b1 and b2, one of which, b1, is configured to be able to fix the other end 224b of the second member 224, and the other connection part, b2, is configured to be able to be connected to the fixing part 35 of the lower boom 41. The fixing part 35 is located within the frame of the rotating side end part 41a. The connection part b2 can also be used when joining one end of the main connection member 21 and the length changing member 22A.

[0069] <Assembly process of the first specification boom> When the crane 1A of the second embodiment is in the transport posture, as shown in Fig. 11(A), the length changing member 22A is shortened, and the connection part b2 at the other end is connected to the fixed part 35 of the lower boom 41. With this configuration, the lower boom 41 is supported by the live mast 6 via the length changing member 22A in a state where it is lifted off the ground. In the crane 1A of the second embodiment, the length changing member 22A is fixed in the above-mentioned state by the live mast 6 and the lower boom 41.

[0070] When assembling the crane 1A in the first specification, first, the worker further lays the live mast 6 from the transportation posture at the assembly site to make the tip side of the lower boom 41 touch the ground (FIG. 11(B)). The touch may be made via a sleeper or the like. Next, the worker removes the connection pin of the connection part b1 between the first member 223 and the second member 224 of the length change member 22A, and raises the live mast 6 (FIG. 11(C)). As a result, the first member 223 slides along the second member 224, and the length change member 22A becomes longer. Next, the worker releases the connection between the lower boom 41 and the length change member 22A (FIG. 12(A)). Furthermore, the worker rotates the live mast 6 to raise the length change member 22A, and connects the other end 223b of the length change member 22A to the upper connection part 416 of the lower boom 41 (FIG. 12(B)).

[0071] Then, the worker carries in the remainder of the boom 4 (the extension boom 43 in Figure 12 (C)), adjusts the height of the live mast 6 and the lower boom 41, and connects the remainder of the boom 4 to the lower boom 41 (Figure 12 (C)).

[0072] Next, the worker releases the connection between the other end 223b of the length changing member 22A and the lower boom 41 (FIG. 12(D)), and connects the other end 223b to one end of the main connecting member 21. After that, the assembly process is performed in the same manner as in the first embodiment.

[0073] Through the above assembly process, the lower boom 41, the extension boom 43 and the upper boom 42 are connected to form the boom 4. Furthermore, the boom 4 and the live mast 6 are connected via the connecting member 20. As a result, the boom 4 is raised and lowered by the rotation of the live mast 6, making it possible to use the crane 1A in the first specification.

[0074] When returning the crane 1A from the first specification usage state to the transportation position, the above assembly steps can be carried out in reverse order.

[0075] <Assembly process of the second specification boom> FIG. 13 is a diagram showing assembly steps 6 and 7 of the second specification of the crane of the second embodiment. When assembling the crane 1A in the second specification, the steps of FIG. 11(A) to FIG. 12(B) are the same as those of the first specification. Next, the worker lays down the live mast 6 to slide the first member 223 of the length changing member 22A along the second member 224, and connects the other end 224b of the second member 224 to the other end 223b of the first member 223 by pin, thereby shortening the length changing member 22A (FIG. 13(A)). After that, the height of the live mast 6 and the lower boom 41 is adjusted, and the rest of the boom 4 is connected to the lower boom 41.

[0076] Next, the worker releases the connection between the other end 223b of the length changing member 22A and the lower boom 41 (FIG. 13(B)), and connects the other end 223b to one end of the main connecting member 21. After that, the assembly process is performed in the same manner as in the first embodiment.

[0077] Through the above assembly process, the lower boom 41, the extension boom 43 and the upper boom 42 are connected to form the boom 4. Furthermore, the boom 4 and the live mast 6 are connected via the connecting member 20. As a result, the boom 4 is raised and lowered by the rotation of the live mast 6, and the crane 1A can be used in the second specification.

[0078] When returning the crane 1A from the second specification usage state to the transportation position, the above assembly steps can be carried out in reverse order.

[0079] As described above, according to the crane 1A of the second embodiment, the crane 1A has the fixing portion 35 that fixes the length changing member 22A to the crane 1A. Therefore, when transporting the crane 1A, it is not necessary to transport the length changing member 22A separately from the crane 1, and when storing the crane 1A, it is not necessary to store the length changing member 22A separately from the crane 1A, improving the workability during transportation and storage. Furthermore, when assembling the crane 1 using the length changing member 22A, it is not necessary to transport the length changing member 22A from a location distant from the crane 1A to the crane 1, improving the workability during assembly of the crane 1A.

[0080] Furthermore, the crane 1A of the second embodiment includes an upper rotating body 3 and a lower boom 41 connected to the upper rotating body 3, and the fixing part 35 of the length changing member 22A is provided on the lower boom 41. In the assembly process of the crane 1, it is convenient if the installation of the length changing member 22A can be performed near the lower boom 41, since this does not require a large movement of the live mast 6. Therefore, by arranging the fixing part 35 as described above, the workability of installing the length changing member 22A can be further improved.

[0081] Furthermore, according to the crane 1A of the second embodiment, the fixing part 35 fixes the length change member 22A in a position in which the longitudinal direction of the length change member 22A faces within 45 degrees from the vertical when the lower boom 41 is in a grounded state. The above angle may be more preferably within 30 degrees, and even more preferably within 15 degrees. When the length change member 22A is assembled, the length change member 22A is in a state of hanging vertically from the tip of the live mast 6. Therefore, since the length change member 22A is fixed as described above, the amount of rotational movement of the length change member 22A can be reduced when assembling the length change member 22A. The length change member 22 has a large weight. And, since the amount of rotational movement can be reduced as described above, the labor required for assembling the length change member 22 is reduced, and the assembling workability of the crane 1A can be improved.

[0082] (Embodiment 3) A crane 1B according to a third embodiment of the present invention is similar to that of the first embodiment, except that the configuration of a length adjusting member 22B and the method of using the same are different. Fig. 14 is a side view showing the lower boom and the length adjusting member of the third embodiment. Figs. 15(A)-(D) and 16(A)-(C) are diagrams showing assembly steps 1-7 of the first specification for the crane of the third embodiment.

[0083] The length changing member 22B includes a first member 226 and a second member 227 having a long shape (such as a rod shape, a long plate shape, or a rope shape), and a bracket 228 that rotatably connects the first member 226 and the second member 227. The bracket 228 further includes a connection portion (for example, a pin hole that can be connected by a pin) 228a.

[0084] In the length changing member 22B, one end 226a of the first member 226 is connected to the tip of the live mast 6. The other end 226b of the first member 226 is rotatably connected to a bracket 228, and one end 227a of the second member 227 is rotatably connected to the bracket 228. Therefore, when the other end 227b of the second member 227 is connected to a connection object and the live mast 6 is raised to pull the length changing member 22B, the length changing member 22B becomes longer than the combined total length of the first member 226 and the second member 227, that is, becomes long.

[0085] On the other hand, if the connection part 228a of the bracket 228 is connected to the connection object and the live mast 6 is raised to pull the length changing member 22B, the length changing member 22B will connect the live mast 6 to the connection object with a length approximately equal to the entire length of the first member 226. In other words, the length changing member 22B can be used in a short form.

[0086] <Assembly process of the first specification boom> When the crane 1B of the third embodiment is in the transport posture, as shown in Fig. 15(A), the other end 227b of the second member 227 of the length changing member 22B is connected to the fixing part 37 located at the upper part of the lower boom 41 (the upper part when lying down), the connecting part 228a of the bracket 228 is connected to the fixing part 38 located within the frame of the rotating side end part 41a of the lower boom 41, and one end 226a of the first member 226 is rotatably connected to the live mast 6. The length changing member 22B is fixed by such connections. Furthermore, the live mast 6 supports the lower boom 41 in a state where it is lifted off the ground via the length changing member 22B connected as described above.

[0087] The fixing portion 37 located at the upper portion of the lower boom 41 may have a configuration corresponding to the upper connection portion 416 in the first and second embodiments.

[0088] When assembling the crane 1B in accordance with the first specification, first, at the assembly site, a worker further lays the live mast 6 down from the transport posture to allow the tip side of the lower boom 41 to touch the ground (FIG. 15(B)). The touch may be via a sleeper or the like. Next, the worker removes the connection pin connecting the bracket 228 of the length changing member 22B to the lower boom 41 (FIG. 15(C)), and raises the live mast 6 (FIG. 15(D) and FIG. 16(A)). This lengthens the length changing member 22B so that it can support the lower boom 41 (FIG. 16(A)).

[0089] Then, the worker carries in the remainder of the boom 4 (such as the extension boom 43 in Figure 16 (B)), raises the live mast 6 and the lower boom 41, and connects the remainder of the boom 4 to the lower boom 41 (Figure 16 (B)).

[0090] Next, the worker releases the connection between the other end 227b of the length changing member 22B and the lower boom 41 (FIG. 16(C)), and connects the other end 227b to one end of the main connecting member 21. After that, the assembly process is performed in the same manner as in the first embodiment.

[0091] Through the above assembly process, the lower boom 41, extension boom 43 and upper boom 42 are connected to form the boom 4. Furthermore, the boom 4 and the live mast 6 are connected via the connecting member 20. The connecting member 20 is configured so that the main connecting member 21 and the length changing member 22B in the long state are connected together. As a result, the boom 4 is raised and lowered by the rotation of the live mast 6, making it possible to use the crane 1B in the first specification.

[0092] When returning the crane 1B from the first specification usage state to the transportation position, the above assembly steps can be carried out in reverse order.

[0093] <Assembly process of the second specification boom> FIG. 17 is a diagram showing an assembly process 7 of the second specification for the crane of the third embodiment. When assembling the crane 1B of the second specification, the processes of FIG. 15(A) to FIG. 16(B) are the same as those of the first specification. Next, the worker lays down the live mast 6, and releases the connection between the other end 227b of the length changing member 22B and the lower boom 41. Furthermore, the worker lays down the live mast 6, thereby lowering the bracket 228 to a position where it can be connected to the main connection member 21 (FIG. 17). Then, the worker connects the connection part 228a of the bracket 228 to one end of the main connection member 21. Thereafter, the same process as the assembly process of the first embodiment is performed.

[0094] Through the above assembly process, the lower boom 41 and the extension boom 43 (and the upper boom 42, if any) are connected to form the boom 4. Furthermore, the boom 4 and the live mast 6 are connected via the connecting member 20 in a short state. As a result, the boom 4 is raised and lowered by the rotation of the live mast 6, and the crane 1B can be used in the second specification.

[0095] When returning the crane 1B from the second specification usage state to the transportation attitude, the above assembly steps can be carried out in reverse order.

[0096] As described above, according to the crane 1B of the third embodiment, the crane 1B has fixing portions 37, 38 for fixing the length changing member 22B to the crane 1B. Therefore, when transporting the crane 1B, it is not necessary to transport the length changing member 22B separately from the crane 1, and when storing the crane 1B, it is not necessary to store the length changing member 22B separately from the crane 1B, improving the workability during transportation and storage. Furthermore, when assembling the crane 1 using the length changing member 22B, it is not necessary to transport the length changing member 22B from a location distant from the crane 1B to the crane 1B, improving the workability during assembly of the crane 1B.

[0097] Furthermore, the crane 1B of the third embodiment includes an upper rotating body 3 and a lower boom 41 connected to the upper rotating body 3, and fixing parts 37, 38 of the length changing member 22B are provided on the lower boom 41. In the assembly process of the crane 1, it is convenient if the installation of the length changing member 22B can be performed near the lower boom 41, since this does not require a large movement of the live mast 6. Therefore, by arranging the fixing part 35 as described above, the workability of installing the length changing member 22B can be further improved.

[0098] Furthermore, according to the crane 1B of the third embodiment, the fixing parts 37, 38 fix the length change member 22B in a position in which the longitudinal direction of the length change member 22B (the longitudinal direction of the first member 226 and the longitudinal direction of the second member 227) is oriented at an angle of 45 degrees or less from the vertical when the lower boom 41 is in a grounded state. The above angle may be more preferably 30 degrees or less, and even more preferably 15 degrees or less. When the length change member 22B is assembled, the length change member 22B is in a state of hanging vertically from the tip of the live mast 6. Therefore, since the length change member 22B is fixed as described above, the amount of rotational movement of the length change member 22B can be reduced when assembling the length change member 22B. The length change member 22 has a large weight. And, since the amount of rotational movement can be reduced as described above, the labor required for assembling the length change member 22 is reduced, and the workability of assembling the crane 1B can be improved.

[0099] The above describes each embodiment of the present invention. However, the present invention is not limited to the above embodiments. For example, the fixing portion for fixing the length change member 22 is not limited to the configuration provided on the lower boom 41, but may be provided on any part of the crane, such as the side frame, the lower frame, or the lower weight. In addition, in the above embodiment, the length change members 22, 22A, and 22B are configured to be changeable to two lengths, but the length change members may be configured to be changeable to three or more lengths. In addition, in the above embodiment 1, the length change member 22 is configured to have one basic length change member 221 and one additional length change member 222, but may be configured to have two or more additional length change members 222. In addition, in the above embodiment, the one end of the length change member 22 is configured not to come off the live mast 6, but the one end may be detachable, and in that case, a fixing portion for fixing the one end may be provided separately on, for example, the rotating side end 41a of the lower boom 41. That is, a configuration in which the entire length change member 22 can be fixed to the fixing portion may be adopted. In addition, in the above embodiment, an example in which a crawler crane is used as the crane is shown, but the crane can be any other mobile crane such as a wheel crane, a truck crane, a rough terrain crane, an all-terrain crane, etc. Furthermore, the crane can be any crane having a boom and a mast such as a tower crane, a jib crane, a retractable crane, etc. In addition, the details shown in the embodiment can be appropriately changed without departing from the spirit of the invention. [Explanation of symbols]

[0100] 1, 1A, 1B Crane 2 Undercarriage 3. Upper rotating body 4. Boom 5. Jib 6 Live Mast 7 Strut 8 Cab 9 Counterweight 10. Hook W1~W3 Wire rope 20 Connection member 21 Main connecting member 22, 22A, 22B Length change member 221 Basic length change parts 222 Additional length change parts 31, 32, 35, 37, 38 Fixed part 33 Connection 41 Lower boom 411 Upper main material 412 Lower main material 414 Joint 416 Upper connection part 42 Upper Boom 43 Continuation boom 50 Judgment Department 51, 52 Sensor 53, 54 Angle gauge 56, 57 Harness 58 Circuit

Claims

1. Boom and Mast and A connecting member that connects the mast and the boom; A crane that raises and lowers the boom by rotating the mast, The connecting member is a crane including a length changing member that can be changed to one of a plurality of specifications including at least a first specification in which the mast and the boom are connected by the connecting member of a first length and a second specification in which the mast and the boom are connected by the connecting member of a second length, A crane comprising a fixing part for fixing the length change member when the length change member is not in use.

2. An upper rotating body and a lower boom connected to the upper rotating body, The fixing portion is provided on the lower boom. The crane of claim 1.

3. The fixing portion fixes the length change member in a position in which the longitudinal direction of the length change member is oriented within 45 degrees from the vertical when the lower boom is in a grounded state. The crane of claim 2.

4. the length change member includes a basic length change member used in both the first specification and the second specification, and an additional length change member used in the first specification and not used in the second specification, When the connection member is in the second specification, the fixing portion fixes the additional length changing member. The crane of claim 2.

5. The fixing portion is disposed on the extension boom side of the lower boom, With the additional length changing member fixed to the fixing portion, a extension boom can be connected to the lower boom. The crane according to claim 4.

6. The fixing portion fixes the additional length changing member at a position lower than the upper main member of the lower boom when the lower boom is in a grounded state. The crane according to claim 4.

7. 5. The crane according to claim 4, wherein said mast is transportable with said lower boom supported via said basic length changing member.

8. the length change member includes a basic length change member used in both the first specification and the second specification, and an additional length change member used in the first specification and not used in the second specification, a determination unit that determines whether the connection member is of the first specification or the second specification based on whether the additional length change member is fixed to the fixing portion, The crane of claim 1.

9. the length change member includes a basic length change member used in both the first specification and the second specification, and an additional length change member used in the first specification and not used in the second specification, the additional length-changing member has a circuit that is a short circuit or a resistive circuit; a harness connectable to the circuit via the mast and the basic length changing member; a determination unit that determines whether the additional length changing member is used based on detection of an electrical variable through the harness; The crane of claim 1.

10. A method for assembling a crane, comprising changing a boom and a mast to a first specification in which the boom and the mast are connected via a connecting member of a first length from a second specification in which the boom and the mast are connected via a connecting member of a second length, the method comprising the steps of: A crane assembling method in which a length change member that was fixed to a fixed part of the crane in the second specification is removed when changing to the first specification, and the boom and the mast are connected with the connecting member including the length change member.

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