JP2018087086A - crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crane capable of both improving a hanging capacity and reducing a tension force required for raising a boom.SOLUTION: A crane has a boom 10 which has a structure capable of changing its length, and a derricking device 11 which guides the boom 10 to pivot and to be derricked relative to an upper pivotable body 4. The derricking device 11 has a coupling device 32 which couples one end of a guy line 30 to a boom head 13. The coupling device 32 has a connection part 36 which is connected with one end of the guy line 30, and a support device 38 which supports the connection part 36 relative to the boom head 13 so that the connection part 36 is disposed at a position away from a rear side 21 of the boom head 13 to the opposite side to a belly side 22. The support device 38 has a first link member 49 which is connected with the connection part 36 and permits a position of the connection part 36 to be shifted to a plurality of different positions in A direction which is orthogonal to a shaft center 10a of the boom 10 and a pivoting shaft of the boom 10.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a crane.

  2. Description of the Related Art Conventionally, a crane including a boom that can be raised and lowered and a raising and lowering device that raises and lowers the boom is known. Patent Document 1 below discloses an example of such a crane.

  In the crane disclosed in Patent Document 1 below, the base end portion of the boom is attached to the front portion of the machine body so as to be rotatable about an axis extending in the width direction of the machine body. A live mast is provided at a position behind the boom of the airframe, and a high mast is provided at a position behind the boom. The live mast and the high mast can be pivoted around their base end portions by being attached to the airframe so that their base end portions can be rotated around an axis extending in the width direction of the airframe. ing.

  A top link is provided on the front side of the tip of the boom, and a hook for hanging a suspended load is suspended from a top sheave provided on the top link via a hook rope. A pendant link is fixed on the rear surface side of the tip of the boom, and the rear end of the pendant link and the tip of the live mast are connected via a pendant corresponding to a guy line.

  Then, the boom rope is wound around the sheave provided at the tip of the high mast and the sheave provided at the tip of the live mast, and the boom rope is wound and fed out by the winch provided on the fuselage. It has become. When the winch winds up the boom rope, the live mast rotates backward so that the tip of the live mast approaches the tip of the high mast. Along with this, the pendant is pulled rearward, the tip of the boom is pulled rearward by the pendant, and the boom stands up.

  In this crane, the pendant link that protrudes backward from the tip of the boom moves the pendant connection position away from the tip of the boom, thereby acting as a resultant force of the pendant tension and the suspension load. The position where the compression force is applied is close to the axis of the boom. Thereby, the suspension capacity is improved by allowing the boom to withstand a large compressive force.

Japanese Patent Laid-Open No. 11-43288

  In a crane, a boom having a structure whose length can be changed is used, and the boom length is generally changed to an appropriate length in accordance with the contents of the hanging work, the situation at the work site, or the like. In the crane disclosed in Patent Document 1, the suspension capacity is improved by providing a pendant link, but when the boom length is reduced, the suspension capacity may be reduced. Further, when the length of the boom is increased, another problem arises in that the tensile force required to cause the boom in a lying state increases.

  Specifically, when the boom length is reduced, the angle between the direction in which the pendant extends and the direction in which the suspension load is applied increases, so that the position where the compressive force is applied moves away from the boom axis. As a result, the bending moment increases, and as a result, the suspension capacity has to be lowered to suppress the bending of the boom. On the other hand, when the length of the boom is increased, the vertical component of the pendant tensile force is reduced because the angle between the pendant and the axis of the boom is reduced in a state where the boom is lying down approximately horizontally. As a result, a greater pendant pulling force is required to cause the boom.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a crane capable of achieving both an improvement in suspension capacity and a reduction in tensile force required to cause a boom.

  In order to achieve the above object, a crane according to the present invention includes a fuselage, a boom attached to the fuselage so as to be rotatable, and having a structure capable of changing a length, and rotating the boom to A hoisting device for raising and lowering the fuselage, the hoisting device being provided at the tip of the boom, a connecting device for connecting one end of the guy line to the tip of the boom, and the guy line rearward And a guy line operating device that causes the boom to fall by sending the guy line forward while pulling to the front, and the tip of the boom has a back surface facing rearward with the boom standing up A connecting portion for connecting to one end of the guy line, and the connecting portion. And a support device that supports the coupling portion with respect to the tip portion so that the tip portion is located at a position away from the back surface of the tip portion to the side opposite to the abdominal surface, and the support device includes the tip of the boom And a support member that supports the member to be coupled between the member to be coupled and the back surface of the tip. The coupled member has a plurality of coupled parts arranged in the longitudinal direction of the coupled member, each of which is detachable from the coupled part, and is in contact with and separated from the back surface of the tip part. The coupling portion is coupled to the mounting portion so as to be rotatable in a direction, and the coupling portion to which the coupling portion is coupled is changed among the plurality of coupled portions, whereby the coupling portion is connected to the axis of the boom and In a first direction orthogonal to the pivot axis of the boom. The support member is coupled to the attachment portion so as to be rotatable in a direction in which the support member contacts and separates from the back surface of the tip portion, and the coupled portion is allowed to be changed to a plurality of different positions. Of the member, a portion provided with the predetermined coupled portion to which the coupling portion is coupled is supported via the coupling portion.

  In this crane, the member to be coupled that is coupled to the coupling portion allows the position of the coupling portion to be changed to a plurality of different positions in a first direction orthogonal to the axis of the boom and the pivot axis of the boom. Thus, it is possible to achieve both an improvement in the suspension capacity and a reduction in the tensile force required to cause the boom.

  Specifically, when the length of the boom is reduced, the connecting portion is disposed at a position further rearward from the axis of the boom in the standing state, and between the direction in which the guy line extends and the direction in which the suspension load is applied. By reducing the angle, it is possible to bring the operating position of the compressive force close to the boom axis from the boom center in the standing state due to the reduced boom length. . As a result, the bending moment generated in the boom can be reduced, the bending of the boom can be reduced, and the suspension capacity can be improved. On the other hand, when the length of the boom is increased, the joint portion is disposed at a position closer to the axis of the boom, so that the guide line with respect to the axis of the boom that has been reduced due to the increase in the length of the boom. The angle can be enlarged. As a result, it is possible to increase the vertical component of the tensile force of the guy line when the falling boom is caused, and as a result, it is possible to reduce the tensile force of the guy line required to cause the boom.

  Further, in this crane, the position of the coupling portion is changed in the first direction by removing the coupling portion that has been coupled to the predetermined coupled portion and coupling it to another coupled portion. Can do. Therefore, it is possible to specifically configure a coupled member that is coupled to the coupling portion and allows the position of the coupling portion to be changed to a plurality of different positions in the first direction.

  Moreover, in this crane, when a coupling part is coupled to a predetermined coupled part selected from a plurality of coupled parts, a part of the coupled member where the predetermined coupled part is provided is supported by the support member. be able to. For this reason, the supporting member can counter the large tension of the guy line applied from the coupling portion to the portion of the coupled member where the predetermined coupled portion is provided, and can prevent deformation and breakage of the coupled member. .

  As described above, according to the present invention, it is possible to provide a crane capable of improving the suspension ability and reducing the tensile force required to cause the boom in a lying state.

It is a side view in case the boom of the crane by 1st Embodiment of this invention exists in a standing state. It is an enlarged view of the boom front-end | tip part of the crane shown in FIG. FIG. 2 is a view corresponding to FIG. 2 showing a form of a guy line offset link adopted when a boom having a length larger than the boom length of the crane shown in FIG. 1 is used. It is a side view of the crane by a comparative example. FIG. 4 is an enlarged view of the tip of the boom for explaining the difference between the compressive force acting on the boom in the crane of the first embodiment shown in FIG. 1 and the compressive force acting on the boom in the crane of the comparative example shown in FIG. It is. It is a side view in case the boom of the crane by 1st Embodiment of this invention exists in a lying state. It is a side view of the crane by 2nd Embodiment of this invention. It is an enlarged view of the boom front-end | tip part of the crane shown in FIG. It is an enlarged view of the boom front-end | tip part of the crane by the modification of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
With reference to FIGS. 1-6, the crane by 1st Embodiment of this invention is demonstrated.

  As shown in FIG. 1, the crane according to the first embodiment includes a lower traveling body 2 configured to be self-propelled and an upper revolving body that is mounted on the lower traveling body 2 so as to be pivotable about a vertical axis. 4 is provided. In this 1st Embodiment, although the lower traveling body 2 is a crawler type, it is not necessarily limited to this, For example, a wheel type may be sufficient.

  In the following description, “front” and “rear” mean front and rear in the upper swing body 4. That is, the right side in FIG. 1 corresponds to “front”, and the left side in FIG. 1 corresponds to “rear”. In the following description, the “width direction” corresponds to the width direction of the upper swing body 4 and is a direction that is horizontal and orthogonal to the front-rear direction. That is, the “width direction” corresponds to a direction perpendicular to the paper surface of FIG.

  As shown in FIG. 1, the crane according to the first embodiment includes a boom 10 attached to the upper swing body 4 of the machine body 6 so as to be rotatable around a rotation axis extending in the width direction, and the boom 10. And a hoisting device 11 for hoisting the upper swing body 4.

  The boom 10 is a lattice boom having a lattice structure and extending in a specific direction. The boom 10 is configured such that its axial length can be changed. The boom 10 includes a boom body 12 and a boom head 13.

  The boom body 12 constitutes most of the boom 10 and is formed by connecting a plurality of unit booms 14 having a lattice structure. The base end portion, which is one end portion in the longitudinal direction of the boom body 12, corresponds to the base end portion of the boom 10 and is attached to the front end portion of the upper swing body 4. The base end portion of the boom body 12 is attached to the upper swing body 4 so as to be rotatable around a rotation axis extending in the width direction. Thereby, the boom 10 can be raised and lowered with the base end portion of the boom body 12 as a fulcrum.

  Each unit boom 14 includes four main members 15 and a plurality of lattice members 16 that connect the main members 15 to each other. In each figure, since the boom 10 is shown as viewed from the side, only two of the four main members 15 are shown. Each main material 15 is disposed at each position corresponding to four vertices of a rectangle in a cross section orthogonal to the longitudinal direction of the boom 10. The axis 10 a of the boom 10 extends in the longitudinal direction of the boom 10 through the center of the four main members 15 in a cross section perpendicular to the longitudinal direction of the boom 10. The corresponding main members 15 of the adjacent unit booms 14 are connected so as to be separable. The length of the boom 10 in the axial direction can be changed by changing the number of unit booms 14 to be connected or changing the unit boom 14 to be used to have a different length in the axial direction.

  The boom head 13 is attached to an end opposite to the base end of the boom body 12 to form the tip of the boom 10. The boom head 13 is an example of the tip of the boom in the present invention. As shown in FIG. 1, the boom head 13 has a back surface 21 facing rearward when the boom 10 is standing, a belly surface 22 facing frontward in this state, and a distal end surface 23 facing upward in that state.

  A top sheave 25 is provided at a portion of the boom head 13 on the stomach surface 22 side so as to be rotatable about a horizontal axis extending in the width direction. As shown in FIG. 1, the hook device 27 is suspended downward from the top sheave 25 via a suspension rope 26. The hook device 27 includes an unillustrated hook sheave that is rotatable. A hanging rope 26 drawn from a hoisting winch (not shown) mounted on the upper swing body 4 is hung around the hook sheave and the top sheave 25. When the hoisting winch winds / unwinds the suspension rope 26, the hook device 27 and the suspended load suspended thereon are wound up / down.

  The hoisting device 11 (see FIG. 1) includes two guy lines 30, two connecting devices 32, and a guy line operating device 34.

  The guy line 30 and the connecting device 32 connect a tip end portion 60b of a crane mast 60, which will be described later, and the boom head 13.

  The two guy lines 30 are arranged separately in the width direction of the upper swing body 4. Since the two guy lines 30 overlap each other when viewed from the side of the upper swing body 4, only one guy line 30 is shown in each figure. The two connecting devices 32 are provided on the boom head 13 and are arranged separately in the width direction. Since these two connecting devices 32 also overlap each other when viewed from the side of the upper swing body 4, only one connecting device 32 is shown in each figure.

  One connecting device 32 connects one end of the corresponding one guy line 30 to the boom head 13. The other connecting device 32 connects one end of the corresponding other guy line 30 to the boom head 13. The other end of each guy line 30 is connected to a tip 60b of a crane mast 60 described later. One connecting device 32 is provided at one end in the width direction of the boom head 13, and the other connecting device 32 is provided at the other end in the width direction of the boom head 13. Since the two connecting devices 32 are configured similarly, the structure of one connecting device 32 will be described below as a representative.

  As illustrated in FIG. 2, the coupling device 32 includes a coupling portion 36 and a support device 38.

  The coupling portion 36 is a portion to which one end of the guy line 30 is coupled. The coupling portion 36 includes a pin 55 and a connection member such as a shackle (not shown) attached to the pin 55. The pin 55 connects a first link member 49 and a second link member 50 described later of the support device 38 to each other. One end of the guy line 30 is coupled to the connecting member attached to the pin 55.

  The support device 38 supports the coupling portion 36 with respect to the boom head 13 so that the coupling portion 36 is located at a position away from the back surface 21 of the boom head 13 to the side opposite to the abdominal surface 22. As shown in FIG. 2, the support device 38 includes a mounting portion 42, a guy line offset link 44 (hereinafter simply referred to as a link 44), and pins 52 and 54.

  The attachment part 42 is a part to which the link 44 is attached. The attachment portion 42 is fixed to the back surface 21 so as to protrude from the back surface 21 of the boom head 13 to the side opposite to the abdominal surface 22, and supports the link 44. As shown in FIG. 2, the attachment portion 42 includes a first attachment member 46 and a second attachment member 47.

  The first mounting member 46 is composed of two plates that are erected on the back surface 21 in the vicinity of the front end surface 23 of the boom head 13. The two plate bodies of the first attachment member 46 are arranged such that their plate thickness directions coincide with the width direction. The two plates are arranged with a slight gap between them in the width direction. Each plate is formed with an attachment hole penetrating them in the thickness direction at the same position.

  The second mounting member 47 is made of a single plate that is erected on the back surface 21. The second mounting member 47 is disposed so that the plate thickness direction thereof coincides with the width direction, and is disposed at a position corresponding to the middle of the two plate bodies of the first mounting member 46. The second attachment member 47 is formed with an attachment hole penetrating the second attachment member 47 in the plate thickness direction. This mounting hole is disposed in the vicinity of the proximal end located on the opposite side (boom body 12 side) to the distal end surface 23 of the boom head 13.

  The link 44 is a support device that is attached to the attachment portion 42 and supports the coupling portion 36. The link 44 can be attached to and detached from the attachment portion 42. As shown in FIG. 2, the link 44 includes a first link member 49 and a second link member 50.

  The first link member 49 is an example of the coupled member of the present invention. The first link member 49 is coupled to the pin 55 of the coupling portion 36. The first link member 49 allows the position of the coupling portion 36 to be changed to a plurality of different positions in the A direction orthogonal to the axis 10 a of the boom 10 and the pivot axis of the boom 10.

  Specifically, the first link member 49 is an elongated flat plate. The first link member 49 is provided with a plurality of holes 49a penetrating the first link member 49 in the plate thickness direction. The hole 49a is an example of a coupled portion in the present invention. The plurality of holes 49 a are arranged at intervals in the longitudinal direction of the first link member 49. The first link member 49 has a base end portion 49b that is one end portion in the longitudinal direction and a distal end portion 49c that is the other end portion in the longitudinal direction. The holes 49a are also arranged at the base end portion 49b and the tip end portion 49c of the first link member 49.

  The base end portion 49 b of the first link member 49 is inserted between the two plates of the first mounting member 46. By inserting the pin 52 into the hole 49a provided in the base end portion 49b and the mounting holes provided in the two plates of the first mounting member 46, the base end portion of the first link member 49 is inserted. 49 b is attached to the first attachment member 46. The pin 52 can be inserted into and removed from the hole 49 a of the base end portion 49 b and the mounting hole of the first mounting member 46. The base end portion 49b can be separated from the first mounting member 46 by extracting the pins 52 from the holes. That is, the base end portion 49 b of the first link member 49 can be attached to and detached from the first attachment member 46.

  The second link member 50 is an example of a support member of the present invention. The second link member 50 extends in a direction intersecting the first link member 49 and the back surface 21 of the boom head 13, and the first link member 49 is interposed between the first link member 49 and the back surface 21 of the boom head 13. support. The 2nd link member 50 consists of two elongate flat plates. The two flat plates are formed in the same shape. Each flat plate of the second link member 50 has a base end portion 50a that is one end portion in the longitudinal direction and a distal end portion 50b that is the other end portion in the longitudinal direction. The base end portion 50a of each flat plate is formed with a hole 51a penetrating the flat plate in the plate thickness direction. A hole 51b that penetrates the flat plate in the thickness direction is formed at the tip 50b of each flat plate.

  The base end portions 50 a of the two flat plates of the second link member 50 are connected to the second mounting member 47. Specifically, these base end portions 50a sandwich the second mounting member 47 from both sides in the plate thickness direction so that the hole 51a overlaps the mounting hole of the second mounting member 47, and in this state, the pin 54 is The base end portion 50 a is inserted into the hole 51 a and the mounting hole of the second mounting member 47. Thereby, the base end portion 50 a of the second link member 50 is attached to the second attachment member 47. The pin 54 can be inserted into and removed from the hole 51 a of the base end portion 50 a and the mounting hole of the second mounting member 47. The base end portion 50a can be separated from the second mounting member 47 by extracting the pins 54 from the holes. That is, the base end portion 50 a of the second link member 50 can be attached to and detached from the second attachment member 47.

  Further, the tip portions 50 b of the two flat plates of the second link member 50 are connected to the first link member 49. Specifically, the tip portions 50b sandwich the first link member 49 from both sides in the plate thickness direction so that the hole 51b overlaps the predetermined hole 49a of the first link member 49. Are inserted into predetermined holes 49a corresponding to the holes 51b. As a result, the distal end portion 50 b of the second link member 50 is attached to the first link member 49. The pin 55 can be inserted into and removed from the hole 51 b of the tip end portion 50 b and the hole 49 a of the first link member 49. By extracting the pin 55 from the holes 49a and 51b, the first link member 49 and the distal end portion 50b of the second link member 50 can be separated from each other. That is, the front end portion 50 b of the second link member 50 is detachably connected to the first link member 49. The second link member 50 supports a portion of the first link member 49 provided with a hole 49a into which the pin 55 is inserted through the pin 55.

  The first link member 49 is attached to the first attachment member 46 and extends in a direction substantially along the A direction while being connected to the second link member 50 attached to the second attachment member 47. That is, the first link member 49 has a predetermined length in the A direction while being supported by the second link member 50 and the pin 55. Since the plurality of holes 49a are arranged in the longitudinal direction of the first link member 49, when the first link member 49 is supported by the second link member 50 and the pin 55, the plurality of holes 49a are formed in the A direction. Are arranged at a plurality of different positions. For this reason, the pin 55 is inserted into the predetermined hole 49a selected from the plurality of holes 49a and the hole 51b of the second link member 50, and the distal end portion 50b of the second link member 50 is placed at the position of the selected hole 49a. By connecting to the one link member 49, the coupling portion 36 can be installed at a predetermined position in the A direction corresponding to the selected hole 49a. Then, the pin 55 is extracted from the predetermined hole 49a and the hole 51b of the second link member 50, the hole 51b of the second link member 50 is aligned with another hole 49a, and the pin 55 is inserted into the holes 49a and 51b. By changing the connecting position of the tip 50b of the second link member 50 with respect to the first link member 49, the position of the coupling portion 36 can be changed in the A direction.

  For example, as shown in FIG. 2, a pin 55 is inserted into the hole 49a provided in the tip 49c of the first link member 49 and the hole 51b of the tip 50b of the second link member 50, and the first When the distal end portion 50b of the second link member 50 is connected to the distal end portion 49c of the link member 49, the coupling portion 36 is separated from the rear surface 21 of the boom head 13 within the range of change of the position of the coupling portion 36 in the A direction. It is arranged at the most distant position.

  For example, as shown in FIG. 3, a hole 49 a provided in a portion closer to the base end portion 49 b than the tip end portion 49 c of the first link member 49 and a hole 51 b of the tip end portion 50 b of the second link member 50. When the pin 55 is inserted and the distal end portion 50b of the second link member 50 is connected to the portion where the hole 49a is provided, the coupling portion 36 is located in the A direction from the position shown in FIG. Is also arranged at a position close to the back surface 21 of the boom head 13.

  As described above, the pin 55 is inserted into the hole 49a positioned closer to the base end portion 49b among the plurality of holes 49a provided in the first link member 49, and the distal end portion 50b of the second link member 50 is attached. If connected, the coupling portion 36 can be disposed at a position closer to the back surface 21 of the boom head 13. On the contrary, if the pin 55 is inserted into the hole 49a located on the distal end portion 49c side among the plurality of holes 49a provided in the first link member 49 and the distal end portion 50b of the second link member 50 is connected. The coupling portion 36 can be disposed at a position further away from the rear surface 21 of the boom head 13 to the side opposite to the abdominal surface 22.

  The guy line operating device 34 (see FIG. 1) is a device that raises the boom 10 by pulling the guy line 30 rearward and falls the boom 10 by sending the guy line 30 forward. The guy line operating device 34 includes a crane mast 60 and a mast rotating device 61.

  As shown in FIG. 1, the crane mast 60 has a base end portion 60 a attached to the upper swing body 4 behind the position where the base end portion of the boom 10 is attached. The base end portion 60a is attached to the upper swing body 4 so as to be rotatable around a horizontal axis extending in the width direction. Thereby, the crane mast 60 can be rotated around the horizontal axis around the base end portion 60a. The other end, which is the end opposite to one end of the guy line 30 connected to the coupling portion 36, is connected to the distal end 60b, which is the end opposite to the base end 60a of the crane mast 60. In a state where the boom 10 stands (see FIG. 1), the distal end portion 60 b of the crane mast 60 is disposed at a position considerably lower than the boom head 13. On the other hand, in a state (not shown) in which the boom 10 is laid down so as to extend substantially horizontally from the upper swing body 4, the boom head 13 is disposed at a position lower than the distal end portion 60 b of the crane mast 60. .

  The mast rotation device 61 is a device that pulls the guy line 30 backward and sends it forward by rotating the crane mast 60. As shown in FIG. 1, the mast rotating device 61 includes an upper spreader 62, a lower spreader 64, a hoisting winch 66, and a hoisting rope 68.

  The upper spreader 62 is attached to the tip 60b of the crane mast 60. The upper spreader 62 has an upper sheave 62a that is rotatable about a horizontal axis extending in the width direction.

  The lower spreader 64 is provided at the rear end of the upper swing body 4. The lower spreader 64 has a lower sheave 64a that is rotatable about a horizontal axis extending in the width direction.

  The undulating winch 66 is mounted on the upper swing body 4. A hoisting rope 68 drawn out from the hoisting winch 66 is wound around the upper sheave 62a and the lower sheave 64a. The hoisting winch 66 performs winding / unwinding of the hoisting rope 68.

  When the hoisting winch 66 winds up the hoisting rope 68, the upper spreader 62 is drawn toward the lower spreader 64, and accordingly, the crane mast 60 is rotated rearward. As a result, the guy line 30 is moved rearward by the crane mast 60. Be pulled. Thereby, the boom head 13 is pulled backward via the guy line 30 and the connecting device 32, and the boom 10 stands up.

  On the other hand, when the hoisting winch 66 feeds the hoisting rope 68, the distance between the upper spreader 62 and the lower spreader 64 is expanded, and the crane mast 60 supports the load and suspension load of the boom 10 via the guy line 30. As a result, the guy line 30 is fed forward. Thereby, the boom 10 falls down forward.

  In the first embodiment, as described above, the coupling portion 36 (see FIG. 2) coupled to one end of the guy line 30 is supported so as to be located at a position away from the rear surface 21 of the boom head 13 to the side opposite to the abdominal surface 22. Supported by device 38. For this reason, the action position of the compressive force acting on the standing boom 10 as a resultant force of the tension of the guy line 30 and the suspension load can be brought close to the axis 10 a of the boom 10. Thereby, the bending moment resulting from the compressive force which acts on the boom 10 becomes small.

  Specifically, as shown in FIG. 5, the compression force P <b> 1 of the boom 10 in the first embodiment is upward in the vertical direction from the extension line of the guy line 30 coupled to the coupling portion 36 and the center of the rotation shaft of the top sheave 25. It is calculated | required as a resultant force which combined the tension | tensile_strength T1 of the guy line 30 and the suspension load W in the intersection N1 with the straight line extended to.

  On the other hand, as shown in FIG. 4, the support device 38 is not provided, and the coupling portion 36 is provided on the second mounting member 47, and the coupling portion 36 is disposed at a position close to the back surface 21 of the boom head 13. A crane is used as a comparative example. In this comparative example, as shown in FIG. 5, the compressive force P2 of the boom 10 is applied at the intersection N2 between the extension line of the guy line 30a and the straight line extending upward in the vertical direction from the center of the rotation axis of the top sheave 25. It is calculated | required as a resultant force which synthesize | combined the tension T2 and the suspension load W.

  As shown in FIG. 5, the distance L1 between the position of the compression force P1 of the boom 10 according to the first embodiment and the axis 10a in the plane perpendicular to the axis 10a of the boom 10 is in the same plane. It becomes smaller than the distance L2 between the action position of the compression force P2 of the boom 10 and the shaft center 10a according to the comparative example. That is, the operating position of the compression force P1 of the boom 10 according to the first embodiment is closer to the axis 10a of the boom 10 than the operating position of the compression force P2 of the boom 10 according to the comparative example. For this reason, the bending moment generated in the boom 10 when the compression force P1 acts on the boom 10 in the first embodiment is smaller than the bending moment generated when the compression force P2 acts on the boom 10 in the comparative example. For this reason, in 1st Embodiment, the bending of the boom 10 by a bending moment can be reduced, and it becomes possible to suspend a bigger suspension load. As a result, the suspension capacity can be improved.

  In the crane according to the first embodiment, the length of the boom 10 is changed by changing the number of joints of the unit booms 14 or changing the unit booms 14 to be used with different lengths. Change to an appropriate length according to the situation at the site. In this case, since the first link member 49 allows the position of the coupling portion 36 to be changed to a plurality of different positions in the A direction, the suspension force is improved and the tensile force required to cause the boom 10 is reduced. And both.

  Specifically, when the length of the boom 10 is reduced, by inserting the pin 55 of the coupling portion 36 into the hole 49a near the distal end portion 49c of the first link member 49, the coupling portion 36 is in an upright state. It arrange | positions in the position which left | separated from the axial center 10a of the boom 10 back more. For example, the coupling part 36 is arranged at the position shown in FIG. In this case, the position of the compressive force that has moved forward from the axial center 10a of the boom 10 in a standing state due to the reduction in the length of the boom 10 is brought closer to the axial center 10a of the boom 10. be able to. For this reason, for the same reason as described above based on FIG. 5, the bending ability of the boom 10 due to the bending moment can be reduced and the suspension capacity can be improved.

  On the other hand, when the length of the boom 10 is increased, the pin 55 of the coupling portion 36 is inserted into the hole 49a positioned closer to the base end portion 49b than the distal end portion 49c of the first link member 49, and the coupling portion 36 is arranged at a position closer to the axial center 10a of the boom 10. For example, the coupling part 36 is arranged at the position shown in FIG. In this case, the angle of the guy line 30 with respect to the axis 10a of the boom 10 in the fallen state, which is reduced due to the increase in the length of the boom 10, can be increased. Specifically, the angle θ shown in FIG. 6 can be enlarged. Thereby, when causing the boom 10 in a lying state, the vertical component of the tensile force of the guy line 30 can be increased. As a result, the tensile force of the guy line 30 required to cause the boom 10 can be reduced.

  In the first embodiment, the second link member 50 extending in the direction intersecting the first link member 49 is provided with a hole 49 a into which the pin 55 of the coupling portion 36 of the first link member 49 is inserted. The part is supported through the pin 55. For this reason, the 2nd link member 50 can oppose the big tension | tensile_strength of the guy line 30 applied to the site | part in which the hole 49a in which the pin 55 of the 1st link member 49 was inserted is provided from the connection part 36. FIG. As a result, deformation and breakage of the first link member 49 can be prevented.

(Second Embodiment)
7 and 8 show the configuration of the crane according to the second embodiment of the present invention. In the crane according to the second embodiment, the relative position of the coupling portion 36 with respect to the boom head 13 can be changed to a plurality of different positions in the B direction along the axial direction of the boom 10 in addition to the A direction. The direction B is an example of the second direction in the present invention.

  Moreover, the crane by this 2nd Embodiment can change the specification into a normal specification and a heavy lift specification. The normal specification and the heavy lift specification are properly used according to the magnitude of the suspended load. That is, when the magnitude of the suspended load is less than or equal to a preset set value, the normal specification is adopted as the crane specification, and when the magnitude of the suspended load is larger than the set value, the crane specification As a heavy lift specification is adopted. And in this 2nd Embodiment, when making a crane into a heavy lift specification, the coupling | bond part 36 is arrange | positioned in the said B direction to the more front end side of the boom 10. FIG. Hereinafter, a specific configuration of the crane according to the second embodiment will be described.

  The normal specification corresponds to the specification of the crane shown in FIG. That is, since the configuration of the crane with the normal specification corresponds to the configuration of the crane according to the first embodiment, the description thereof is omitted here.

  The heavy lift specifications correspond to the crane specifications shown in FIG. In this heavy lift specification, the guy line operating device 34 includes an HL mast 76 different from the crane mast 60 in addition to the crane mast 60 and the mast rotating device 61. In addition, the crane mast 60 in this 2nd Embodiment is an example of the 1st mast by this invention. The HL mast 76 is an example of a second mast according to the present invention.

  The HL mast 76 is a mast having a lattice structure and extending in a specific direction. The HL mast 76 includes a base end portion 76a that is one end portion in the axial direction of the HL mast 76 and a front end portion 76b that is an end portion on the opposite side to the base end portion 76a.

  The base end portion 76a is detachably attached to the upper swing body 4. The base end portion 76 a is attached to the upper swing body 4 so as to be rotatable around a common axis with the base end portion 60 a of the crane mast 60. Thereby, the HL mast 76 rotates between the boom 10 and the crane mast 60 around the base end portion 76a.

  In the second embodiment, the guy line operating device 34 includes a connecting rope 78 that connects the distal end portion 60 b of the crane mast 60 and the distal end portion 76 b of the HL mast 76. The connecting rope 78 is an example of a connecting member according to the present invention. Further, the ends of the two guy lines 30 opposite to the connecting device 32 are connected to the tip 76 b of the HL mast 76. Thereby, the front-end | tip part 76b of the HL mast 76 and the boom head 13 are connected via the guy line 30 and the coupling device 32. The distal end portion 76 b of the HL mast 76 is disposed at a position higher than the distal end portion 60 b of the crane mast 60.

  In this second embodiment, the mast rotating device 61 rotates the HL mast 76 via the connecting rope 78 by rotating the crane mast 60, thereby pulling the guy line 30 backward and moving it forward. Send out.

  In the second embodiment, the mounting portion 42 of the support device 38 supports the first link member 49 and changes the position of the first link member 49 to a plurality of different positions in the B direction. Allow.

  Specifically, the attachment portion 42 includes a first attachment member 46 and a second attachment member 47 configured in the same manner as the first attachment member 46 and the second attachment member 47 of the first embodiment, and another third An attachment member 48 and a fourth attachment member 56 are included. The first mounting member 46 and the third mounting member 48 in the second embodiment are examples of the mounting member in the present invention.

  The third mounting member 48 is composed of two plates that are erected from the distal end surface 23 at a position near the stomach surface 22 in the distal end surface 23 of the boom head 13. Accordingly, the third mounting member 48 is provided on the boom head 13 at a position different from the first mounting member 46 in the B direction, and is disposed on the more distal end side of the boom 10 than the first mounting member 46. The two plate bodies of the third attachment member 48 are arranged such that their plate thickness directions coincide with the width direction. The two plates are arranged with a slight gap between them in the width direction, and are arranged at positions that coincide with the two plates of the first mounting member 46 in the width direction. Each plate body of the third attachment member 48 is formed with an attachment hole penetrating them in the thickness direction at the same position.

  The fourth mounting member 56 is formed of a single plate that is erected from the distal end surface 23 at a position near the rear surface 21 of the distal end surface 23 of the boom head 13. The fourth attachment member 56 is arranged so that the thickness direction thereof coincides with the width direction. The fourth attachment member 56 is disposed at a position corresponding to the middle of the two plates of the third attachment member 48 in the width direction. The fourth mounting member 56 is formed with a mounting hole penetrating the fourth mounting member 56 in the thickness direction.

  The first attachment state S1 (see FIG. 8) in which the link 44 is attached to the first and second attachment members 46, 47 to the second attachment state S2 in which the link 44 is attached to the third and fourth attachment members 48, 56. By changing the attachment state of the link 44 to the attachment portion 42 (see FIG. 8), it is allowed to change the position of the first link member 49 to a plurality of different positions in the B direction.

  The first attachment state S1 is the same as the attachment state of the link 44 of the first embodiment shown in FIG. In the first attachment state S1, the first link member 49 is attached to the first attachment member 46, and the second link member 50 is attached to the second attachment member 47. In the first attachment state S <b> 1, the position of the coupling portion 36 (pin 55) supported by the link 44 is closer to the boom main body 12 side (base end side of the boom 10) than the distal end surface 23 of the boom head 13. . This first attachment state S1 is employed in the normal specification of the crane.

  On the other hand, in the second attachment state S2, as shown in FIG. 8, the base end portion 49b of the first link member 49 is attached to the third attachment member 48 and the base end portion 50a of the second link member 50 is attached. Is attached to the fourth attachment member 56.

  In the second mounting state S2, the base end portion 49b of the first link member 49 is inserted between the two plates of the third mounting member 48, and the hole 49a provided in the base end portion 49b and the first end The base end portion 49 b of the first link member 49 is attached to the third attachment member 48 by inserting the pin 52 into the attachment hole of each plate body of the third attachment member 48. The pin 52 can be inserted into and removed from the hole 49 a of the base end portion 49 b and the mounting hole of the third mounting member 48. The base end portion 49 b can be separated from the third mounting member 48 by extracting the pins 52 from those holes. That is, the base end portion 49 b of the first link member 49 can be attached to and detached from the third attachment member 48.

  Further, in the second attachment state S2, the base end portions 50a of the two flat plates of the second link member 50 have the plate thickness of the fourth attachment member 56 such that the hole 51a overlaps the attachment hole of the fourth attachment member 56. In this state, the pin 54 is inserted into the hole 51a of each base end portion 50a and the mounting hole of the fourth mounting member 56. Thereby, the base end portion 50 a of the second link member 50 is attached to the fourth attachment member 56. The pin 54 can be inserted into and removed from the hole 51 a of the base end portion 50 a and the mounting hole of the fourth mounting member 56. By extracting the pins 54 from the holes, the base end portion 50 a can be separated from the fourth mounting member 56. That is, the base end portion 50 a of the second link member 50 can be attached to and detached from the fourth attachment member 56.

  In the second attachment state S2, the link 44 projects from the tip end surface 23 of the boom head 13 to the opposite side of the boom body 12 in the B direction. Accordingly, the coupling portion 36 supported by the link 44 is installed at a position spaced from the distal end surface 23 of the boom head 13 to the side opposite to the boom body 12 (the side opposite to the base end portion of the boom 10). This second attachment state S2 is adopted in the heavy lift specification of the crane.

  The other configuration of the crane according to the second embodiment is the same as the configuration of the crane according to the first embodiment.

  In the second embodiment, the bending of the boom 10 caused by the heavy lift specification can be reduced while the crane can be used for the heavy lift specification to perform the suspension work with a large lifting load.

  Specifically, in the normal specification of the crane (see FIG. 1), the distal end portion 60b of the crane mast 60 is disposed at a position considerably lower than the boom head 13 of the boom 10 in the standing state. The angle with the shaft center 10a is reduced, and as a result, the tensile force component of the guy line 30 in the direction orthogonal to the shaft center 10a of the boom 10 is reduced. For this reason, in the normal specification, it is difficult to suspend a large suspension load. On the other hand, by attaching the HL mast 76 to the upper swing body 4 and making the crane a heavy lift specification, the boom head 13 of the boom 10 in the standing state is positioned at a position higher than the distal end portion 60b of the crane mast 60. The guy line 30 is connected to the front end portion 76b of the HL mast 76 arranged at a close height position. For this reason, the angle of the guy line 30 with respect to the axis 10a of the boom 10 is larger than that in the normal specification, and the tensile force component of the guy line 30 in the direction orthogonal to the axis 10a of the boom 10 can be increased. it can. As a result, in the heavy lift specification, it is possible to perform suspension work with a suspension load larger than the suspension load that can be suspended in the normal specification.

  When the crane is in the heavy lift specification, the link 44 is moved from the position of the first attachment state S1 in the normal specification to the position of the second attachment state S2, and the coupling portion 36 is disposed at a position on the more distal end side of the boom 10. To do. Thereby, the angle between the guy line 30 and the axis 10a of the boom 10 can be adjusted to a slightly smaller angle.

  Specifically, as shown in FIGS. 7 and 8, when the link 44 is in the second attachment state S2 and the connecting portion 36 and the tip 76b of the HL mast 76 are connected by the guy line 30, The angle between the guy line 30 and the axis 10a of the boom 10 is slightly smaller than when the coupling part 36 and the tip 76b of the HL mast 76 are connected by the guy line 30 in the first mounting state S1. In this case, as compared with the case where the link 44 is in the position of the first attachment state S1, the direction in which the boom head 13 is pulled by the guy line 30 can be slightly downward, and the tensile force applied to the boom 10 in the A direction is reduced. Can weaken ingredients a little. As a result, it is possible to reduce the bending that occurs in the boom 10 in the heavy lift specification.

  Further, when the HL mast 76 is removed from the upper swing body 4 and the crane is returned from the heavy lift specification to the normal specification, the link 44 is returned to the position of the first attachment state S1 protruding from the rear surface 21 of the boom head 13. The same effects as those of the first embodiment can be obtained.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, the coupling portion of the present invention is not necessarily limited to the configuration shown in the above embodiment. For example, the coupling portion may include a pin 55, a second link member 50, and a connection portion provided on the second link member 50. In this case, the connecting portion is a portion to which the guy line 30 is connected, and is provided at, for example, an intermediate portion between the proximal end portion 50a and the distal end portion 50b of the second link member 50. In this case, the hole 49a of the first link member 49 that connects the tip 50b of the second link member 50 via the pin 55 is changed to another hole 49a, so that the second link member 50 is pin 54. It is possible to change the relative position of the connecting portion (connecting portion) with respect to the boom head 13 to a plurality of different positions in the A direction.

  Further, the coupled member of the present invention that couples with the coupling portion and allows the position of the coupling portion to be changed to a plurality of different positions in the A direction is not necessarily limited to the first link member 49 described above. Instead of the first link member 49, a member other than the first link member 49 can be used as the coupled member of the present invention.

  Further, the mounting portion of the present invention that supports the coupled member and allows the position of the coupled member to be changed to a plurality of different positions in the B direction is not necessarily limited to the mounting portion 42 described above. Instead, a configuration other than the mounting portion 42 can be employed as the mounting portion of the present invention.

  Moreover, the attachment form with respect to the boom head 13 of the 1st link member 49 and the 2nd link member 50 in 2nd attachment state S2 may be an attachment form like the modification shown in FIG.

  Specifically, in this modification, the attachment portion 42 includes a first attachment member 46, a second attachment member 47, and a third attachment member 60. The structure of the 1st attachment member 46 and the 2nd attachment member 47 is the same as that of the case of the said embodiment.

  The third mounting member 60 is provided on the distal end surface 23 of the boom head 13 at the same position as the third mounting member 48 of the second embodiment. However, the third attachment member 60 is composed of a single plate erected from the distal end surface 23. The third attachment member 60 is arranged so that the thickness direction thereof coincides with the width direction. The third mounting member 60 is disposed at a position that coincides with the position of the second mounting member 47 in the width direction. That is, the third mounting member 60 is disposed at a position corresponding to the middle of the two plates of the first mounting member 46 in the width direction. The third attachment member 60 is formed with an attachment hole that penetrates the third attachment member 60 in the plate thickness direction.

  And in 2nd attachment state S2 of this modification, the base end part 49b of the 1st link member 49 is attached to the 1st attachment member 46 similarly to 1st attachment state S1. However, in the second attachment state S2, the first link member 49 is disposed so as to protrude from the distal end surface 23 of the boom head 13.

  Further, in the second attachment state S <b> 2 of this modification, the base end portion 50 a of the second link member 50 is attached to the third attachment member 60. The attachment method of the base end portion 50 a to the third attachment member 60 is the same as the attachment method of the base end portion 50 a to the second attachment member 47. Therefore, the base end portion 50 a of the second link member 50 can be attached to and detached from the third attachment member 60.

  In this modification, when changing from the first attachment state S1 to the second attachment state S2, the pin 54 connecting the base end portion 50a of the second link member 50 to the second attachment member 47 is removed, and the second attachment state is obtained. The base end portion 50a is separated from the member 47, and the first link member 49 is rotated from the position in the first attachment state S1 in the direction of arrow D in FIG. The first link member 49 and the second link member 50 are arranged at the position of the second attachment state S2 shown in FIG. 9 by rotating the first link member 49 so as to be folded around the pin 55 as an axis. Then, the base end portion 50 a of the second link member 50 is connected to the third mounting member 60 by the pin 54. Moreover, in this modification, when changing from 2nd attachment state S2 to 1st attachment state S1, the change operation | work is performed in the reverse procedure to when changing from 1st attachment state S1 to 2nd attachment state S2.

6 Airframe 10 Boom 11 Hoisting device 13 Boom head (the tip of the boom)
21 Back 22 Abdominal Surface 30 Guy Line 32 Connecting Device 34 Guy Line Operating Device 36 Connecting Portion 38 Supporting Device 42 Mounting Portion 46 First Mounting Member (Mounting Member)
48 Third mounting member (mounting member)
49 First link member (joined member)
49a hole (joined part)
50 Second link member (support member)
60 Crane mast (first mast)
61 Mast rotation device 76 HL mast (second mast)
78 Connection rope (connection member)

Claims (1)

The aircraft,
A boom having a structure that is attached to the airframe so as to be rotatable and whose length can be changed;
A hoisting device for turning the boom and hoisting the airframe;
The hoisting device includes a guy line, a connecting device that is provided at the tip of the boom and connects one end of the guy line to the tip of the boom, and pulls the guy line backward to raise the boom, Including a guy line operating device that overturns the boom by feeding the guy line forward,
The tip of the boom has a back surface facing rearward when the boom is raised, and a belly surface facing frontward when the boom is raised,
The coupling device includes: a coupling portion coupled to one end of the guy line; and the coupling portion with respect to the distal end portion so that the coupling portion is located at a position away from the back surface of the distal end portion to the side opposite to the abdominal surface. And a supporting device for supporting
The support device includes an attachment portion fixed to the back surface of the tip portion of the boom, a coupled member coupled to the coupling portion, and the coupled member and the back surface of the distal portion. A support member that supports the member to be coupled;
The coupled member has a plurality of coupled parts arranged in the longitudinal direction of the coupled member, each of which is detachable from the coupled part, and is in a direction of coming into contact with and separated from the back surface of the tip part. The coupling portion is coupled to the mounting portion so as to be rotatable, and the coupling portion to which the coupling portion is coupled is changed among the plurality of coupled portions, whereby the coupling portion is connected to the boom axis and the boom. Allowed to be changed to a plurality of different positions in a first direction orthogonal to the rotation axis of
The support member is connected to the attachment portion so as to be rotatable in a direction in which the support member is brought into contact with or separated from the back surface, and the predetermined coupled portion in which the coupling portion is coupled among the coupled members. The crane which supports the site | part in which the part was provided through the said connection part.

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