JP4661813B2 - Crane with jib - Google Patents

Description

  The present invention relates to a crane with a jib that includes a boom and a jib that is rotatably connected to the tip of the boom and that can be disassembled in a predetermined posture.

  Some cranes equipped with a boom have a relatively large jib rotatably connected to the tip of the boom in order to expand the working range. In order to safely dismantle such a crane with a jib, it is necessary to form a posture in which the boom falls and further the jib lies on the ground.

2. Description of the Related Art Conventionally, as a means for facilitating such a transition to a dismantling posture, one provided with a wheel as described in Patent Document 1 is known. The wheel is rotatably attached to the tip of the jib, and the attachment position is set so that the tip of the jib is landed on the ground before the jib is lowered. Specifically, it is set at a position protruding from the tip of the jib toward the abdominal surface of the jib. This wheel can roll on the ground by its rotation after landing, and the operation of projecting the jib is smoothly performed using the rolling while the boom is lying down. And by this operation, the attitude | position which lies on the ground in the state which the said boom and the said jib finally opened at about 180 degrees is achieved.
JP 2002-46981 A

  As described above, considerable space is required for dismantling with the jib fully projecting from the boom. When such a space cannot be secured, instead of the above-mentioned projecting posture, the jib is landed in a folded state on the abdominal surface side (falling side) of the boom as shown in FIG. An internal hug is adopted.

  However, since this hugging posture is a posture in which the back side of the jib lands, the wheel cannot be used effectively. Specifically, in order for the wheel to land earlier than any part of the jib in the overhanging posture, the wheel needs to be positioned on the abdominal surface side with respect to the central axis of the jib. Although the position is set (Patent Document 1), in order to position the wheel on the ground side with respect to any part of the jib in the holding posture, the wheel is on the back side with respect to the central axis of the jib. There must be. Therefore, if the wheel is provided at a position on the abdominal surface side of the jib for the purpose of landing in the overhanging posture as described above, the wheel cannot function in the holding posture.

  As a method for eliminating such inconvenience, that is, as a method for making the wheels available for both postures, it is conceivable to replace the wheels according to the postures. Is cumbersome and inefficient.

  In view of such circumstances, the present invention provides a crane capable of using a common wheel even when either an extended posture or an internal holding posture is selected as the dismantling posture of the crane in a simple operation. For the purpose.

As means for solving the above-mentioned problems, the present invention provides a crane main body, a boom connected to the crane main body so as to be rotatable in a hoisting direction, and a tip of the boom parallel to the rotation central axis of the boom. A projecting posture in which the boom falls down and the jib projects from the boom along the ground, as a posture for disassembling the boom and the jib. In a crane with a jib in which the boom is folded down and an internal holding posture in which the jib is folded with respect to the boom so that the jib is close to the lower surface of the boom in the lying state can be selected, A wheel support member that is rotatably mounted about an axis parallel to the rotation center axis of the jib, and is rotatably supported by the wheel support member. The wheel support member is provided with a wheel-side connecting portion at a position deviating from the rotation center axis of the wheel support member. The member is provided with a rotating side connecting portion that fixes the wheel supporting member to the overhanging supporting position by being detachably connected to the wheel side connecting portion at a position deviated from the rotating central axis, The wheel side connecting portion is detachably connected to the tip end of the jib at a position away from the rotation center axis of the wheel support member and the rotation member, so that the wheel support member is brought into an internal holding support position. A jib-side connecting portion to be fixed is provided, and the support position for the extension of the wheel support member is such that the boom stands up from the extension posture and the tip of the jib is grounded when the jib falls on the boom. Close to the first The wheel is a position where the wheel can roll on the ground from the ground position to the extended position, and the support position for the inner holding of the wheel support member is higher than the inner holding position. And the position where the wheel can roll on the ground from the second landing posture in which the tip of the jib approaches the ground to the inner holding posture due to the jib lying on the boom Further, the wheel support member or the jib has a position at which the rotating member is separated from the wheel and the ground when the wheel side connecting portion is connected to the jib side connecting portion. The holding member is attached to the tip of the jib so as to be rotatable about an axis parallel to the rotation center axis of the wheel support member. Provided on the wheel support member. The wheel support member is moved from the overhanging support position while rolling the wheel on the ground in a posture in which the tip of the jib is directed downward and the rotating member is suspended from the tip of the jib. It is in a position to receive the lower end portion of the pivoting member in the suspended position when it pivots to the internal holding support position .

  According to this crane, the wheel support member itself can be switched between the overhang support position and the internal support position by turning the wheel support member. That is, the wheel supported by the wheel support member is switched between a position suitable for disassembly in the extended position and a position suitable for disassembly in the holding position by the rotation of the wheel support member. Such position switching by turning the wheel support member eliminates the need to attach and detach these wheels and wheel support members to the jib in order to switch the positions of the wheels and the wheel support members. To increase work efficiency.

  Furthermore, in this crane, while the wheel support member is fixed to the overhang support position by the connection of the wheel side connection portion of the wheel support member and the rotation side connection portion of the rotation member, the wheel side connection The wheel support member is fixed to the internal support position by the connection of the part and the jib side connection part of the jib. Therefore, by selecting the connection destination of the wheel side connection part from the rotation side connection part and the jib side connection part, the wheel can be used for both the overhang support position and the internal hug support position. The support member can be fixed.

  In addition to this, when the support position for the internal hug is selected and the rotating member is separated from the wheel side connecting portion, the holding portion provided on the wheel supporting member or the jib holds the rotating member. By holding, the rotating member is prevented from contacting the wheel or the ground. This enables the wheel to roll well in the holding position without performing a cumbersome operation of removing the rotating member from the tip of the jib.

In addition, the holding portion is provided on the wheel support member, and the tip of the jib is directed downward and the rotating member hangs down from the tip of the jib while rolling on the ground of the wheel. Since the wheel support member is in a position to receive the lower end portion of the pivoting member in the suspended posture when the wheel support member rotates from the support position for overhanging to the support position for internal holding, from the support position for overhanging In addition to the switching of the wheel support member to the internal holding support position, it is not necessary to perform a special operation for holding the lower end portion of the rotating member on the holding portion, thereby further improving work efficiency.

  Further, the wheel support member is extended to the wheel support member while rolling the wheel on the ground in a posture in which the tip of the jib is directed downward and the rotating member is suspended from the tip of the jib. If there is provided a guide portion that guides the lower end portion of the hanging member in the suspended posture to the holding position by the holding portion when rotating from the supporting position to the inner holding supporting position, the rotating member The lower end of is more reliably guided to the holding part. Thereby, the holding reliability of the said rotation member increases.

  In the present invention, in addition to the above-described components, a main winding point sheave that is rotatably provided at the tip of the jib and on which a main winding rope for hanging loads is hung, and is rotatable on the rotating member And an auxiliary winding point sheave on which an auxiliary winding rope for a suspended load is hung. Further, the main winding rope that is suspended from the main winding sheave when the suspension operation is performed in the overhanging posture at the support position for the overhang or the suspension tool provided on the main winding rope and the auxiliary winding By setting the position of the auxiliary winding point sheave to the position where interference with the auxiliary rope hanging from the sheave or the suspension provided on the auxiliary rope is avoided, The hanging work used can be performed.

The present invention also includes a crane main body, a boom connected to the crane main body so as to be rotatable in a hoisting direction, and connected to the tip of the boom so as to be rotatable about an axis parallel to the rotation central axis of the boom. The boom and the jib are disassembled as postures for disassembling the boom and the jib, and an overhanging posture in which the jib projects from the boom along the ground, In a crane with a jib that allows selection of an internal holding posture in which the jib is folded with respect to the boom so that the jib is close to the lower surface of the boom, the tip of the jib is parallel to the rotation center axis of the jib. A wheel support member that is pivotally mounted about an axis, a wheel that is rotatably supported by the wheel support member and that can roll on the ground by the rotation, and a wheel that rotates around the tip of the jib. And capable mounted rotating member, rotatably provided on the tip of the jib, and hanging the main hoisting points sheave main winding rope is multiplied for load, rotatably mounted to said wheel support member, suspended An auxiliary winding point sheave on which a load auxiliary winding rope is hung, and a jib side connected to the wheel support member at a position away from the center axis of rotation of the wheel support member at the tip of the jib A connecting portion is provided, and the wheel support member is configured such that, by rotating, the boom stands up from the projecting posture, and the jib tip falls close to the boom so that the tip of the jib approaches the ground. A projecting support position at which the wheels can roll on the ground from the landing position 1 to the projecting position, and the boom stands up from the inner holding position and is in front of the boom. Switching from the second landing position where the tip of the jib is close to the ground to the inner-holding position when the jib falls down switches to an inner-holding support position where the wheel can roll on the ground. The wheel support member is provided with a first connection part and a second connection part that are detachably connected to the jib side connection part, and the first connection part includes the first connection part and the first connection part. The wheel support member is provided at a position where the wheel support member is fixed to the overhanging support position by connection to the jib side connection portion, and the second connection portion is connected to the jib side connection portion by the connection between the second connection portion and the jib side connection portion. A wheel support member is provided at a position where the support member is fixed to the internal support position, and the overhang support position is suspended from the main roll sheave when a suspension operation is performed in the overhang posture. Rope or rope for this main winding Is a position where interference between the hoisting rope provided on the auxiliary hoisting sheave and the auxiliary hoisting rope suspended from the auxiliary hoisting sheave or the hoisting equipment provided on the auxiliary hoisting rope is avoided, and the wheel and the auxiliary hoisting point The sheave is provided so as to be rotatable about a common axis, and the wheel has a larger diameter than the point sheave .

According to the present invention, the support position for the overhang is set to the main winding rope suspended from the main winding sheave or the suspension provided on the main winding rope when the suspension work is performed in the overhanging posture. By making the position for avoiding interference with the auxiliary winding rope suspended from the winding sheave or the suspension provided on the auxiliary winding rope, the auxiliary winding point can be obtained by using the overhang landing posture. Suspension work using a sheave can be performed . Further, the wheel and the auxiliary winding point sheave are provided so as to be rotatable about a common axis, and the wheel has a larger diameter than the point sheave, so that the wheel and the auxiliary winding point are provided. Simplifying the structure and making the arrangement compact by sharing the rotating shaft of the sheave, the diameter of the auxiliary sheave point sheave is that the auxiliary sheave point sheave touches the ground when the wheel is landing. The difference is surely avoided.

  As described above, according to the present invention, it is possible to use a common wheel in a simple operation even when either the extended posture or the internal holding posture is selected as the dismantling posture of the crane. Can be smoothly and efficiently performed.

The implementation of the embodiment of the present invention will be described with reference to FIGS. 1 to 12.

  FIG. 1 shows an overall configuration of a crane 10 according to this embodiment. The crane 10 includes a revolving body 12 corresponding to a crane body, a traveling body 14 that supports the revolving body 12 in a turnable manner, a hoisting member that includes a boom 16 and a jib 18, and a mast 20 that is a boom hoisting member. A counterweight 13 is loaded on the rear part of the revolving unit 12.

  The boom 16 shown in the drawing is a so-called lattice type, and includes a base end side member 16A, one or a plurality of (two in the illustrated example) intermediate members 16B and 16C, and a front end side member 16D. Specifically, the base end side member 16 </ b> A is connected to the front portion of the revolving body 12 so as to be rotatable in the undulation direction. The intermediate members 16B and 16C are detachably added to the distal end side of the base end side member 16A in that order. The distal end side member 16D is detachably connected to the distal end side of the intermediate member 16C, and a rear strut 21 and a front strut 22 for rotating the jib 18 as described later are attached to the distal end portion of the distal end side member 16D. Are rotatably coupled.

  However, the specific structure of the boom is not limited in the present invention. For example, the boom may be composed of a single member.

  Although the specific structure of the jib 18 is not limited, it has a lattice structure in the illustrated example. And the base end part of this jib 18 is connected with the front-end | tip part of said front end side member 16D so that rotation is possible, The rotation center axis | shaft of the said jib 18 is rotation of the said boom 16 with respect to the said rotary body 12. The horizontal axis is parallel to the central axis. This rotation makes it possible to realize both an overhanging posture and a holding posture described later.

The mast 20 has a base end and a rotation end, and the base end is rotatably connected to the revolving body 12. The pivot axis is parallel to the pivot axis of the boom 16 and is located immediately behind the pivot axis of the boom 16. That is, the mast 20 can be rotated in the same direction as the undulation direction of the boom 16. On the other hand, the rotating end of the mast 20 is connected to the tip of the boom 16 via a pair of left and right boom guy lines 24. This connection links the rotation of the mast 20 with the rotation of the boom 16.

  A pair of left and right backstops 23 are provided on the revolving structure 12. These backstops 23 come into contact with the left and right sides of the base end side member 16A of the boom 16 when the boom 16 reaches the standing posture shown in FIG. To prevent it from being beaten backwards

  The rear strut 21 is held in a posture that protrudes from the tip of the tip side member 16D to the boom standing side (left side in FIG. 1). As means for maintaining this posture, a pair of left and right backstops 25 and a pair of left and right guy lines 26 are interposed between the rear strut 21 and the boom 16. The backstop 25 is interposed between the distal end side member 16D and the intermediate portion of the rear strut 21, and supports the rear strut 21 from below. The guy line 26 is stretched so as to connect the distal end portion of the rear strut 21 and the proximal end side member 16A, and the position of the rear strut 21 is regulated by the tension.

  The front strut 22 is connected to the jib 18 so as to rotate in conjunction with the jib 18. Specifically, a pair of left and right jib guy lines 28 are stretched so as to connect the front end of the front strut 22 and the front end of the jib 18. Accordingly, the jib 18 is also rotationally driven by the rotational driving of the front strut 22.

  Various winches are mounted on the crane 10. Specifically, a boom hoisting winch 30 for raising and lowering the boom 16, a jib hoisting winch 32 for rotating the jib 18 in the hoisting direction, and lifting and lowering a suspended load. The main winding winch 34 and the auxiliary winding winch 36 are mounted. In the crane 10 according to this embodiment, the boom hoisting winch 30 is installed in the vicinity of the base end of the mast 20. Further, the jib hoisting winch 32, the main winding winch 34, and the auxiliary winding winch 36 are all installed on the base end side member 16 </ b> A of the boom 16. These winches 30, 32, 34, 36 may be mounted on the revolving structure 12.

  The boom hoisting winch 30 winds and unwinds the boom hoisting rope 38. The boom hoisting rope 38 is routed so that the mast 20 is rotated by the winding and unwinding. Specifically, sheave blocks 40 and 42 in which a plurality of sheaves are arranged in the width direction are provided at the rotating end portion of the mast 20 and the rear end portion of the revolving body 12, respectively. The drawn boom hoisting rope 38 is stretched between the sheave blocks 40 and 42. Accordingly, when the boom hoisting winch 30 winds and unwinds the boom hoisting rope 38, the distance between the sheave blocks 40, 42 changes, and thereby the mast 20 and further interlock with the mast 20. The boom 16 rotates in the undulation direction.

The jib hoisting winch 32 winds and feeds the jib hoisting rope 44. Then, the jib hoisting rope 44 is routed so that the front strut 22 is rotated by the winding and feeding. Specifically, a guide sheave 46 is provided at the longitudinal intermediate portion of the rear strut 21, and a plurality of sheaves have a width at the rotating end portion of the rear strut 21 and the rotating end portion of the front strut 22. Sheave blocks 47 and 48 arranged in a direction are provided, and the jib hoisting rope 44 pulled out from the jib hoisting winch 32 is hung on the guide sheave 46 and hung between the sheave blocks 47 and 48. Passed. Therefore, the winding and unwinding of the jib hoisting rope 44 by the jib hoisting winch 32 changes the distance between the sheave blocks 47 and 48, and raises and lowers the front strut 22 and the jib 18 associated therewith. Rotate in the direction.

  The main winding winch 34 performs hoisting and lowering of the suspended load by the main winding rope 50. With respect to the main winding, main winding guide sheaves 52, 53, and 54 are rotatably provided at the vicinity of the proximal end of the rear strut 21, the vicinity of the proximal end of the front strut 22, and the tip of the jib 18, respectively. Further, a main winding sheave block in which a plurality of main winding point sheaves 56 are arranged in the width direction is provided at a position adjacent to the main winding guide sheave 54, and is pulled out from the main winding winch 34. Further, the main winding rope 50 is hung on the main winding guide sheaves 52, 53, 54 in order, and the main winding point sheave 56 of the sheave block and the sheave block provided on the main hook 57 for suspended loads. It is spanned between the sheaves 58. Accordingly, when the main winding winch 34 winds or feeds the main winding rope 50, the distance between the sheaves 56 and 58 changes, and the main hook 57 is wound and lowered.

  Similarly, the auxiliary winding winch 36 performs lifting and lowering of the suspended load by the auxiliary winding rope 60. With respect to this auxiliary winding, auxiliary winding guide sheaves 62, 63, 64 are rotatably provided coaxially with the main winding guide sheaves 52, 53, 54, respectively, at positions adjacent to the auxiliary winding guide sheave 64. An auxiliary winding point sheave 66 as shown in FIG. 4 described later is rotatably provided. The auxiliary winding rope 60 drawn out from the auxiliary winding winch 36 is hung on the auxiliary winding guide sheaves 62, 63, 64 in order and is suspended from the auxiliary winding point sheave 66. Accordingly, when the auxiliary winding winch 36 winds or unwinds the auxiliary winding rope 60, a supplementary hook for unillustrated suspension connected to the end of the auxiliary winding rope 60 is wound or lowered. It is done.

  Next, the dismantling work of this crane 10 and the structure for it are demonstrated.

  The crane 10 is transported in a disassembled state. The dismantling work includes a work of separating the boom 16 and the mast 20 from the revolving structure 12. In order to perform this dismantling work safely, the boom 16 and jib 18 need to be in a posture lying on the ground.

  When shifting to such a posture, first, as shown in FIG. 2, the jib 18 is in a landing posture (first landing posture) in which the jib 18 projects outward (right side in FIG. 2) from the tip of the boom 16. The tip of 18 is lowered onto the ground G. Then, by continuing the overhang of the jib 18 as it is, the jib 18 and the boom 16 are shifted to an overhanging posture that extends in a straight line (that is, a posture in which the jib 18 is fully opened to about 180 °). Such an overhanging posture is a posture that is excellent in stability and has less stress on the boom 16 and the jib 18.

  However, since the space for the dismantling work is small, there is a case where the projecting posture cannot be taken. In that case, an internal holding posture as shown in FIG. 3 is adopted. This internal holding posture is a posture folded so that the abdominal surface (surface on the lying side) of the jib 18 and the abdominal surface of the boom 16 are close to each other, and this posture is less stable than the overhanging posture, but is space. It is a posture that does not require.

Therefore, the overhanging posture and the holding posture are appropriately selected depending on the size of the space for dismantling work, but in either case, the first landing posture shown in FIG. In order to shift from the landing posture similar to the above to the overhanging posture or the holding posture, it is necessary that the tip of the jib 18 smoothly moves on the ground G. Therefore, in this embodiment, a pair of left and right wheels 70 that can roll on the ground G are provided at the tip of the jib 18. As a feature of the crane 10, the wheel 70 is attached to the tip of the jib 18 so that it can be used when shifting to either the extended position or the internal holding position. The mounting structure of the wheel 70 will be described with reference to FIGS.

  The wheel 70 has a larger diameter than the auxiliary winding point sheave 66 and is rotatably supported by a common wheel support member 72 in a coaxial arrangement with the auxiliary winding point sheave 66. The wheel support member 72 is attached to the tip of the jib 18 so as to be rotatable about a pin 74 parallel to the rotation center axis of the jib 18. The rotation of the wheel support member 72 is as shown in FIG. 3 in which the wheel support member 72 itself is suitable for the suspension work as shown in FIG. 1 and the transition to the extended posture as shown in FIG. It is possible to switch to an internal support position suitable for shifting to the internal support posture.

  Here, the overhanging support position is such that the wheel 70 can land on the ground G before the tip of the jib 18 in the first landing posture as shown in FIG. This is a position where the wheel 70 can roll on the ground G until it reaches the overhanging posture. On the other hand, the support position for the internal holding is such that the boom 16 stands up slightly from the first landing posture and the jib 18 rotates relative to the boom 16 so that the tip of the jib 18 is close to the ground G. The wheel 70 is a position where the wheel 70 can roll on the ground G at a position below the jib 18 from the second landing position to the holding position as shown in FIG.

  The first landing posture and the second landing posture may be the same. That is, it may be possible to shift from the common landing posture to either the overhanging posture or the internal holding posture. Examples of such a common landing posture include a posture in which the jib 18 is suspended substantially vertically downward from the tip of the boom 16.

  The wheel support member 72 includes a pair of left and right first main members 75 and a pair of left and right second main members 76 that are located closer to the back surface (stand-up surface) of the jib 18 than the first main members 75. Have. The first main members 75 and the second main members 76 are connected to each other via a reinforcing member 78, and the first main member 75 and the second main member 76 are connected to each other via a reinforcing plate 80. . That is, all the seed materials 75 and 76 are integrated so as to move together.

  On the other hand, the jib 18 has a pair of left and right mounting plates 19 at the tip thereof, and the rear end portions (lower end portions in FIG. 4) of the first main members 75 are respectively connected to the mounting plates 19 via the pins 74. And are pivotally connected. The positions of these pins 74 are set at positions (right positions in FIG. 4) of the mounting plate 19 on the side of the abdominal surface (the lying side surface) of the jib 18.

  The first main material 75 and the second main material 76 are arranged in a V shape such that the distance between the first main material 75 and the second main material 76 decreases toward the front end side, and the end portions on the front end side are respectively connected to the left and right shaft support portions 82. Yes. The wheel 70 and the auxiliary winding point sheave 66 are pivotally supported by these pivotal support portions 82.

  Specifically, a cylindrical boss 83 is fixed to each of the shaft support portions 82 so as to pass through the shaft support portion 82 in a direction parallel to the rotation center axis of the jib 18, and the support shaft 84 is inserted into the boss 83. It is fixed. Both the wheel 70 and the auxiliary winding point sheave 66 are rotatably attached to the support shaft 84. The auxiliary winding point sheave 66 is attached to the support shaft 84 via a sheave bearing 86 in a region between the shaft support portions 82, and the wheels 70 are attached to both ends of the support shaft 84. ing. These wheels 70 have a disk-shaped inner wall 70a and a cylindrical peripheral wall 70b joined to the peripheral edge of the inner wall 70a. The outer peripheral surface of the peripheral wall 70b constitutes a rolling surface, and Inner walls 70 a are rotatably attached to both ends of the support shaft 84 via wheel bearings 88.

In addition to the wheel support member 72, a rotation link (rotation member) 90 is provided at the tip of the jib 18.
Is installed. Then, the wheel support member 72 is selectively fixed to the projecting support position and the inner support position by using the rotation link 90.

  The pivot link 90 includes a pair of left and right main members 92 extending in parallel to each other and a sub member 94 that connects these main members 92 to each other. The positions of the main members 92 in the width direction of the jib 18 correspond to the positions of the second main members 76 of the wheel support member 72. Then, one end portion (base end portion) in the longitudinal direction of each main material 92 is disposed on the rear side portion (left side portion in FIG. 4) of the distal end of the mounting plate 19 via a pin 96 parallel to the pin 74. The pin 96 is pivotally connected around the pin 96. On the other hand, the other end portion (tip portion) of each of the main members 92 is a rotation side connecting portion 98 into which the connecting pin 100 as a connecting material can be inserted. In addition, a jib-side connecting portion 102 through which the pin 96 can be inserted is provided at a position adjacent to the pin 96 at the tip end of the jib 18 on the jib abdominal surface side.

  On the other hand, the base end portion of the second main member 76 of the wheel support member 72 (the end portion on the side close to the tip end of the jib 18), that is, the portion that is disengaged from the pin 74 that is the rotation center axis, A wheel side connecting portion 104 through which the connecting pin 100 can be inserted is provided. The wheel-side connecting portion 104 is connected to the wheel-side connecting portion 98 by inserting the connecting pin 100 through the wheel-side connecting portion 104 and the rotating-side connecting portion 98, while the wheel-side connecting portion 104 is connected to the wheel-side connecting portion 98. When the connecting pin 100 is inserted into the connecting portion 104 and the jib side connecting portion 102, the connecting portion 104 is connected to the jib side connecting portion 102. The wheel side connecting portion 104 is connected to the rotating side connecting portion 98, whereby the wheel support member 72 is fixed to the overhanging support position shown in FIGS. Each of the connecting portions 98, 102, and 104 is connected to the jib side connecting portion 102 so that the wheel support member 72 is fixed to the internal support position shown in FIG. The position of is set.

  Further, the wheel support member 72 is provided with a holding portion 110. The holding part 110 is disconnected from the wheel side connecting part 104 when an inner holding support position is selected as the position of the wheel support member 72 and the wheel side connecting part 104 is connected to the jib side connecting part 102. The rotating link 90 is held.

  The holding portion 110 rotates the rotation link 90 so as to prevent the rotation link 90 from coming into contact with the wheel 70 or the ground G (that is, hold at a position that does not affect the rolling of the wheel 70). The link 90 is held, and has a pair of left and right support plates 112, a connecting pipe 114, and a stopper pin 116.

  The support plates 112 project from the bosses 83 in the direction substantially perpendicular to the first main member 76 along the radial direction and to the back side, and the ends of the support plates 112 connect the connecting pipe 114 to each other. Connected through. The stopper pin 116 protrudes outward from the side surface of each support plate 112, and the amount of protrusion is sufficient for the tip of the stopper pin 116 to overlap the main material 92 of the pivot link 90. Is set.

  As shown in FIGS. 7 to 11, the stopper pin 116 is positioned so that the tip of the jib 18 faces downward and the rotating link 90 hangs down from the tip of the jib 18. When the wheel support member 72 is rotated from the overhanging support position (FIG. 7) to the inner support position (FIG. 11) while rolling upward, each of the rotary links 90 in the suspended posture is rotated. The lower end portion of the main material 92 is set to a position so as to enter the holding position between the stopper pin 116 and the support shaft 84.

Furthermore, the wheel support member 72 according to this embodiment is provided with a pair of left and right guide plates 118 for guiding the lower end portion of the main material 92 to the holding position. These guide plates 11
8 has a guide surface extending from the back surface of the second main material 76 to the boss 83, and the lower end portion of the main material 92 slides on the guide surface. Details thereof will be described later.

  Next, the position switching of the wheel support member 72 in the crane 10 with jib and the dismantling work using the position switching will be described.

  During normal suspension work as shown in FIG. 1, the jib 18 is projected outward from the tip of the boom 16 (that is, the jib 18 stands up with respect to the boom 16). At this time, as the position of the wheel support member 72, an overhang support position as shown in FIG. 4 is adopted, and the wheel support member 72 is fixed at this position. This fixing is performed by connecting the wheel side connecting portion 104 of the wheel support member 72 and the rotating side connecting portion 98 of the rotating link 90, and this connection is made between the main material 92 of the rotating link 90 and the wheel. This is performed by inserting a common pin 100 through the connecting portions 104 and 98 in a state where the second main member 76 of the support member 72 is arranged in a straight line. The relative rotation between the main material 92 and the second main material 76 around the pin 100 is such that the support plate 119 provided on the second main material 76 side rotates the main material 92. This is prevented by coming into contact with the side surface of the moving side connecting portion 98.

  This overhanging support position is a position where the wheel 70 and the auxiliary winding point sheave 66 overhang on the abdomen surface side of the jib 18 further than the main winding point sheave 56 at the tip of the jib 18. A position where the main winding rope 50 and the main hook 57 hanging from the point sheave 56 do not interfere with the auxiliary winding rope 60 hanging from the auxiliary winding point sheave 66 supported by the wheel support member 72 and the unillustrated auxiliary hook. It is. Therefore, by adopting this position, lifting and lowering of the suspended load using the main winding rope 50 and the auxiliary winding rope 60 can be performed without any trouble.

  On the other hand, when the crane 10 is disassembled, first, the operation of lowering the jib 18 on the ground G by tilting the boom 16 with the posture at the time of operation (the posture corresponding to the first landing posture) is performed. . At this time, since the wheel support member 72 is fixed at the overhang support position, the wheel 70 lands before any part of the jib 18 as shown in FIGS.

  After the landing, as the dismantling posture, the posture in which the boom 16 and the jib 18 are aligned in a straight line, that is, the projecting posture in which the jib 18 opens approximately 180 ° with respect to the boom 16 is adopted. From the state shown in FIG. 7, the extension of the jib 18 to the boom 16 (rotation in the standing direction) and the fall of the boom 16 may be performed in parallel. At this time, since the wheel 70 landing on the ground G rolls on the ground G as it is, the overhanging of the jib 18 is smoothly advanced in a stable state.

  On the other hand, when the working space is small and the projecting posture cannot be taken, the internal holding posture as shown in FIG. 3 is adopted. This internal holding posture is a posture in which the abdominal surface of the jib 18, that is, the surface on the lying side is folded so as to be close to the abdominal surface of the boom 16, that is, the surface on the lying side. However, there is an advantage that it can be formed in a limited work space.

  In order to shift to the internal holding posture, it is necessary to switch the position of the wheel support member 72 as the boom 16 and the jib 18 rotate. Specifically, for example, it is achieved by sequentially performing the following operations.

  1) Pull out the connecting pin 100 from the rotating side connecting part 98 and the wheel side connecting part 104 to separate the connecting parts 98 and 104 from each other.

  2) Lift the tip of the jib 18 slightly to lift the wheel 70 from the ground G. As shown in FIG. 8, this operation causes the wheel 70 and the wheel support member 72 to hang from the pin 74 and also causes the rotation link 90 to hang from the pin 96. Due to these droops, the rotation-side connecting portion 98 is largely separated from the wheel-side connecting portion 104 of the wheel support member 72 toward the back side (right side in FIG. 8).

  3) The tip of the jib 18 is lowered and the wheel 70 is landed again. At the time of this re-landing, as shown in FIG. 9, the rotation center axis (support shaft 84) of the wheel 70 is positioned on the back side of the jib 18 with respect to the rotation center axis (pin 74) of the wheel support member 72. The wheel support member 72 is tilted with respect to the vertical axis. This inclined state can be automatically generated by setting the center of gravity of the wheel support member 72.

  4) The tip of the jib 18 is further lowered little by little to increase the inclination of the wheel support member 72 (FIG. 10). Then, the connecting portions 104 and 102 are connected to each other by passing the connecting pin 100 through the connecting portions 104 and 102 at a position where the wheel side connecting portion 104 and the jib side connecting portion 102 of the wheel support member 72 coincide with each other. (FIG. 11). As a result, the wheel support member 72 is fixed to an internal support position where the wheel 70 projects from the tip of the jib 18 to the back side (right side in FIG. 11). At this time, the posture of the boom 16 and the jib 18 is the second landing posture, and the lower end portion of each main material 92 of the rotary link 90 which is separated from the wheel side connecting portion 104 and becomes a free end portion is While sliding on the guide surface of the guide plate 118 provided on the wheel support member 72, it slides between the support shaft 84 and the stopper pin 116 and is held at this position (holding position).

  5) While the wheel 70 is rolling on the ground G, the rotation of the jib 18 relative to the boom 16 (rotation in the folding direction) and the rotation of the boom 16 in the collapse direction are appropriately performed. By making it parallel, it finally shifts from the second landing posture to the holding posture as shown in FIGS. At this time, the wheel 70 supported by the wheel support member 72 at the inner support position protrudes to the back side of the jib 18 so that the wheel 70 is lower than any part of the jib 18. Keep the side position. Therefore, the rolling of the wheel 70 on the ground G continues to prevent the jib 18 from contacting the ground G even during the movement of the jib 18. Further, since the holding portion 110 including the stopper pin 116 holds the rotation link 90, the rotation link 90 is prevented from hanging down on the ground G or coming into contact with the wheel 70. This helps the wheel 70 to roll normally.

  As described above, in this crane 10 with a jib, the position of the wheel 70 can be switched by the rotation of the wheel support member 72 without changing the wheel 70. Furthermore, the wheel support member 72 is selectively connected by connecting the wheel side connection portion 104 of the wheel support member 72 to the rotation side connection portion 98 of the rotation link 90 and the jib side connection portion 102 on the jib 18 side. It can be fixed to either the overhanging support position or the internal support position. Moreover, when the wheel side connecting portion 104 is connected to the jib side connecting portion 102 and the rotating link 90 is separated from the wheel side connecting portion 104, the main material 92 of the rotating link 90 Holding the end portion by the holding portion 110 prevents the rotation link 90 from hindering the rolling of the wheel 70.

In particular, in this embodiment, as shown in FIGS. 7 to 11, the tip of the jib 18 is directed downward and the rotating link 90 is suspended from the tip of the jib 18. When the wheel support member 72 rotates from the projecting support position to the inner support position while rolling on the ground, the lower end portion of the main member 92 of the pivot link 90 in the suspended position is Since it is automatically received by the holding portion 110 (that is, slips between the stopper pin 116 and the support shaft 84), no special work for holding the rotating link 90 is required.
This further increases work efficiency.

  However, the holding part according to the present invention is not limited to the illustrated one. For example, the rotation link 90 may be manually set, or may be provided on the tip side of the jib 18.

Next, a first embodiment different from the embodiment of the present invention will be described with reference to FIGS. The crane wheel support member according to this embodiment has a first link 138 and a second link 140.

The first link 138 is equivalent structures and wheel support member 72 according to the above embodiment, i.e., has a structure having a pair of left and right first main material 75 and the second main material 76 and the shaft support 82, the pin 74 Is connected to the connecting plate 19 of the jib 18 so as to be rotatable around the center.

  The second link 140 has a second connecting portion 147 having a hole into which the connecting pin 100 can be inserted at one end thereof, and a first connecting portion 146 into which the pin 101 can be inserted at the other end. . The connecting pin 100 is also provided in a hole in the wheel side connecting portion 104 provided at the end of the second main member 76 and also in a hole in the jib side connecting portion 102 provided in the connecting plate 19 on the jib 18 side. The second link 140 and the first link 138 can be rotated around the pin 100 by being inserted into the second connecting portion 147 and the wheel side connecting portion 104. Connect as possible. On the other hand, the connecting pin 101 can be removably inserted into a hole of another jib side connecting portion 103 provided at a position adjacent to the jib side connecting portion 102 in the connecting plate 19.

  The first link 138 can be switched between the overhang support position shown in FIG. 13 and the internal support position shown in FIG. 17 and can be fixed at each position by rotating around the pin 74. It is. Specifically, as shown in FIG. 13, the connecting pin 100 is inserted into the second connecting portion 147 and the wheel side connecting portion 104 in a state where the second connecting portion 147 and the wheel side connecting portion 104 overlap with each other, and the jib side connecting portion 103. When the connecting pin 101 is inserted in a state where the first connecting portion 146 and the first connecting portion 146 overlap with each other, the first link 138 is fixed to the overhanging support position. On the other hand, as shown in FIG. 17, when the wheel-side connecting portion 104 and the second connecting portion 147 overlap the jib-side connecting portion 102, the connecting pin 100 is inserted into the jib-side connecting portion 102. One link 138 is fixed at the supporting position for the internal holding.

  The second link 140 has a guided groove 144 that penetrates the second link 140 in the thickness direction. The guided groove 144 forms a straight line parallel to a straight line connecting the second connecting part 147 and the first connecting part 146. On the other hand, a guide pin 142 that fits into the guided groove 144 protrudes from the connecting plate 19, and the guide pin 142 is separated from the jib side connecting portion 103 and the first connecting portion 146. In this state, the second link 140 is guided so that the second link 140 draws a specific movement locus as the first link 138 rotates. This movement locus is a locus that can avoid interference between the second link 140 and the jib 18 and members attached to the jib 18 (for example, guide sheaves 54 and 64).

In the form status of this, as in the form of pre-you facilities, the first link 138 is switched to the Body supporting position among shown in FIG. 17 from projecting supporting position shown in FIG. 13 in the procedure, for example, the following .

  1) In the state shown in FIG. 13, the connecting pin 101 is pulled out from the jib side connecting portion 103 and the first connecting portion 146 to separate the connecting portions 103 and 146.

  2) As shown in FIG. 14, the wheel 70 and the first link 138 are suspended from the pin 74 by slightly lifting the tip of the jib 18 and floating the wheel 70 from the ground G. Due to this drooping, the first link 138 is slightly inclined to the jib back side (right side in FIG. 14), and the jib side connecting portion 103 is slightly separated from the first connecting portion 146.

  3) The tip of the jib 18 is lowered and the wheel 70 is landed again. During this re-landing, the wheel 70 rolls slightly to the jib back side (FIG. 15).

  4) The tip of the jib 18 is further lowered gradually to increase the inclination of the first link 138 (FIG. 16). The jib side connecting portion 102 is also connected to the connecting pin at a position where the wheel side connecting portion 104 of the first link 138 and the second connecting portion 147 of the second link 140 coincide with the jib side connecting portion 102 of the connecting plate 19. By passing 100, the connecting portions 102, 104, and 145 are connected in a coaxial position (FIG. 17). As a result, the first link 138 is fixed to the inner holding support position where the wheel 70 projects beyond the tip of the jib 18 to the back side (right side in FIG. 17), and the boom 16 and the jib 18 are fixed to the second landing. Take a posture. The second link 140 receives the guidance of the guide pin 142 and draws a trajectory that avoids interference with the jib 18 and the members attached to the jib 18 when reaching the inner holding support position. It rotates around the connecting pin 100.

Accordingly, even in the jib with the crane 10 according to the shape condition of this, I replaced it is possible to perform the position switching without wheels 70, projecting supporting position of the first link 138 using connecting pins 100 and 102 It can be fixed to any of the supporting positions for holding the inner body. In particular, the connection pin 100 that connects the first link 138 and the second link 140 can be used effectively for fixing the holding position for the inner holding.

A second embodiment different from the embodiment of the present invention is shown in FIGS.

The wheel support member according to the second embodiment includes a first link 121 and a second link 150. The first link 121 includes an end that is rotatably connected to a connecting plate 19 provided at the tip of the jib 18 via a pin 123, and an end that is rotatably connected to a support shaft 124 of the wheel 70. Part. The second link 150 expands and contracts to allow the rotation of the first link 121 around the pin 123, and the first link 121 extends to the overhanging support position and the internal holding support position. It has a structure in which the expansion / contraction can be fixed in the expansion / contraction state to be positioned respectively.

  Specifically, the second link 150 has a so-called telescope type telescopic structure. Specifically, the second link 150 is composed of three cylindrical link members 151, 152, and 153, and the link member 151 has an inner diameter into which the link member 152 can be inserted. The link member 153 has an inner diameter into which the link member 153 can be inserted. One end of the link member 151 is rotatably connected to the support shaft 124, and the link member 152 is slidably inserted into the other end. One end of the link member 153 is rotatably connected to the connecting plate 19 on the jib 18 side via a pin 158, and the other end is slidably inserted into the link member 152.

  The entire second link 150 expands and contracts while sliding between the links 151, 152, and 153. The second link 150 expands most when the first link 121 is in the overhanging support position shown in FIG. 18, and contracts most when the first link 121 is in the internal support position shown in FIG. To do. And it has the structure which can fix the expansion-contraction in the most contracted state and the most contracted state, respectively.

  Specifically, pin insertion holes 154, 155, and 156 are formed in the end portions on the jib side (upper end portions in FIGS. 18 to 20) of both end portions of the link members 151, 152, and 153, respectively. Pin insertion holes 157 and 158 are also drilled in the end portions of the link members 152 and 153 on the wheel side (lower end portions in FIGS. 18 to 20). As shown in FIG. 18, the pin insertion hole 154 and the pin insertion hole 157, and the pin insertion hole 155 and the pin insertion hole 158 are aligned with each other when the second link 150 is most extended as shown in FIG. In this fully extended state, the fixing pin 161 is inserted into the pin insertion holes 154 and 157, and the fixing pin 162 is inserted into the pin insertion holes 155 and 158, whereby the second link 150 is fixed in the same state. . On the other hand, as shown in FIG. 20, the pin insertion holes 154, 155, and 156 are positioned so as to coincide with each other when the second link 150 is most contracted, and the pin insertion holes 154 to 156 are in the most contracted state. When the common fixing pin 160 is inserted into the second link 150, the second link 150 is fixed in the same state.

The crane according to the shape condition of this, by the first link 121 is rotated about the pin 123 accompanied by expansion and contraction of the second link 150, shown in projecting supporting position and 20 shown in FIG. 18 It is switched to the supporting position for the internal holding. In addition, the expansion and contraction of the second link 150 can be fixed by the fixing pins 161 and 162 in the most extended state shown in FIG. 18, and this fixing fixes the first link 121 to the overhanging support position in FIG. Similarly, the expansion and contraction of the second link 150 can be fixed by the fixing pin 160 even in the most contracted state shown in FIG. 20, and this fixing fixes the first link 121 to the overhanging support position in FIG.

In the above in each form state described, but the said auxiliary hoisting point sheave 66 respectively to the wheel support member in addition to the wheel 70 is mounted, the mounting of the auxiliary hoisting point sheave 66 is indispensable in the Absent. However, the structure is simplified by adopting a configuration in which the wheel 70 and the auxiliary winding point sheave 66 are rotatably supported by a common shaft (support shaft 84 or support shaft 124 in the illustrated example) as described above. In addition, downsizing of the arrangement is realized.

It is an overall side view showing the hanging work state of the jib with the crane according to the implementation of the embodiment of the present invention. It is a whole side view which shows the landing state in the extended attitude | position of the said crane with a jib. It is a whole side view which shows the landing state in the internal holding attitude | position of the said crane with a jib. It is a side view which shows the wheel and wheel support member of the said crane with a jib in the said suspension work state. FIG. 5 is a view taken in the direction of arrow V in FIG. It is the VI-VI sectional view taken on the line of FIG. It is a side view which shows the state which the said wheel landed in the state in which the said wheel support member was being fixed to the overhang | supporting support position. It is a side view which shows the state by which the wheel side connection part of the said wheel support member was cut | disconnected from the rotation side connection part of the rotation link in the state where the said wheel floated. It is a side view which shows the state which the said wheel re-landed. It is a side view which shows the state which the tilting of the said wheel support member advanced after the said wheel re-landed. It is a side view which shows the state in which the said wheel support member reached | attained the support position for internal holding and was fixed. It is a side view which shows the said wheel and the said wheel support member in the state which the said crane with a jib reached the holding position. The implementation of the embodiment of the present invention is a side view showing a state where the wheel landed with the first link is secured to the projecting supporting position according to another first embodiment. It is a side view which shows the state which the wheel floated in the state which the 1st connection part of the 2nd link cut | disconnected from the jib side connection part in the said 1st form. It is a side view which shows the state which the wheel re-landed in the said 1st form. It is a side view which shows the state which the tilting of the said 1st link advanced after the wheel landed again in the said 1st form. It is a side view which shows the state which the 1st link reached | attained the support position for internal holding in the said 1st form, and was fixed. The implementation of the embodiment of the present invention is a side view showing a state where the wheel landed with the first link is secured to the projecting supporting position according to another second embodiment. In a 2nd form, it is a side view which shows the state in the middle of the said 1st link shifting from the said overhanging support position to the internal support position. It is a side view which shows the state in which the said 1st link was fixed to the said internal support position in the 2nd form.

G Ground 10 Crane with jib 12 Rotating body (crane body)
16 boom 18 jib 50 main winding rope 56 main winding point sheave 57 main hook 60 auxiliary winding rope 66 auxiliary winding point sheave 70 wheel 72 wheel support member 84 support shaft 90 rotation link (rotation member)
96 pins (rotation center axis)
98 Rotating side connecting portion 100 Connecting pin 102 Jib side connecting portion 104 Wheel side connecting portion 110 Holding portion 118 Guide plate 121 First link 122 Second link 123 Pin (rotating central axis)
124 Support shaft 125 First connection hole 126 Second connection hole 128 Guided groove 130 Rotating holding plate 132 Guide pin 134 Connection pin 136 Jib side connection hole 138 First link 140 Second link 142 Guide pin 144 Guided Groove 146 First connecting portion 147 Second connecting portion 150 Second link 151-153 Link member 160-162 Fixing pin

Claims (4)

A crane main body, a boom connected to the crane main body so as to be rotatable in the undulation direction, and a jib connected to the tip of the boom so as to be rotatable about an axis parallel to the rotation central axis of the boom. The boom and the jib are disassembled in an overhanging posture in which the boom overturns and the jib overhangs from the boom along the ground surface, and on the lower surface of the boom in the overturned and inflated state. In a crane with a jib that allows selection of an internal holding posture in which the jib is folded with respect to the boom so that the jib is close,
A wheel support member attached to the tip of the jib so as to be rotatable about an axis parallel to the rotation center axis of the jib;
A wheel rotatably supported by the wheel support member and capable of rolling on the ground by the rotation;
A rotating member that is rotatably attached to the tip of the jib,
The wheel support member is provided with a wheel side connecting portion at a position deviating from the rotation center axis thereof,
The rotating member is provided with a rotating side connecting portion that is detachably connected to the wheel side connecting portion at a position deviating from the rotation center axis, thereby fixing the wheel supporting member to the overhanging supporting position. And
The wheel support member is attached to the front end of the jib by removably connecting the wheel side connecting portion at a position away from the rotation center axis of the wheel support member and the rotation member. Jib side connecting part to be fixed to is provided,
The support position for the extension of the wheel support member is the first landing posture in which the tip of the jib is close to the ground when the boom stands up and the jib falls on the boom from the protruding posture. It is a position where the wheel can roll on the ground until it reaches an overhanging posture,
The support position for internal holding of the wheel support member is a second landing posture in which the boom stands up from the internal holding posture and the tip of the jib approaches the ground when the jib falls on the boom. The wheel is a position where the wheel can roll on the ground from the inner holding posture to
Further, the wheel support member or the jib holds the rotating member at a position where the rotating member is separated from the wheel and the ground when the wheel side connecting portion is connected to the jib side connecting portion. A holding part is provided ,
The pivot member is attached to the tip of the jib so as to be pivotable about an axis parallel to the pivot center axis of the wheel support member,
The holding portion is provided on the wheel support member, and the wheel while rolling on the ground of the wheel in a posture in which the tip of the jib is directed downward and the rotating member is suspended from the tip of the jib. A crane with a jib, wherein the support member is in a position to receive the lower end portion of the pivoting member in the suspended posture when the support member pivots from the overhanging support position to the internal support position . The crane with a jib according to claim 1 ,
The wheel support member is supported by the wheel support member while rolling the wheel on the ground in a posture in which the tip end of the jib is directed downward and the rotating member is suspended from the tip end of the jib. A crane with a jib provided with a guide portion for guiding a lower end portion of the pivoting member in the suspended posture to a holding position by the holding portion when rotating from a position to the support position for holding the inside. . The crane with a jib according to claim 1 or 2 ,
A main-winding point sheave that is rotatably provided at the tip of the jib and on which a main-winding rope for a suspended load is hung;
An auxiliary winding point sheave that is rotatably attached to the wheel support member and on which an auxiliary winding rope for hanging is hung.
The overhang support position includes the main winding rope that is suspended from the main winding sheave when the hanging operation is performed in the overhanging posture, or a suspension provided on the main winding rope and the auxiliary winding sheave. A crane with a jib, wherein the crane is in a position where interference with the suspended winding rope or the suspension provided on the auxiliary winding rope is avoided. A crane main body, a boom connected to the crane main body so as to be rotatable in the undulation direction, and a jib connected to the tip of the boom so as to be rotatable about an axis parallel to the rotation central axis of the boom. The boom and the jib are disassembled in an overhanging posture in which the boom overturns and the jib overhangs from the boom along the ground surface, and on the lower surface of the boom in the overturned and inflated state. In a crane with a jib that allows selection of an internal holding posture in which the jib is folded with respect to the boom so that the jib is close,
A wheel support member attached to the tip of the jib so as to be rotatable about an axis parallel to the rotation center axis of the jib;
A wheel rotatably supported by the wheel support member and capable of rolling on the ground by the rotation;
A rotating member rotatably attached to the tip of the jib ;
A main winding point sheave that is rotatably provided at the tip of the jib and on which a main winding rope for a suspended load is hung;
An auxiliary winding point sheave that is rotatably attached to the wheel support member and on which an auxiliary winding rope for hanging is hung .
The wheel support member is provided with a wheel side connecting portion at a position deviating from the rotation center axis thereof,
The rotating member is provided with a rotating side connecting portion that is detachably connected to the wheel side connecting portion at a position deviating from the rotation center axis, thereby fixing the wheel supporting member to the overhanging supporting position. And
The wheel support member is attached to the front end of the jib by removably connecting the wheel side connecting portion at a position away from the rotation center axis of the wheel support member and the rotation member. Jib side connecting part to be fixed to is provided,
The support position for the extension of the wheel support member is the first landing posture in which the tip of the jib is close to the ground when the boom stands up and the jib falls on the boom from the protruding posture. It is a position where the wheel can roll on the ground until it reaches an overhanging posture,
The support position for internal holding of the wheel support member is a second landing posture in which the boom stands up from the internal holding posture and the tip of the jib approaches the ground when the jib falls on the boom. The wheel is a position where the wheel can roll on the ground from the inner holding posture to
Further, the wheel support member or the jib holds the rotating member at a position where the rotating member is separated from the wheel and the ground when the wheel side connecting portion is connected to the jib side connecting portion. A holding part is provided ,
The overhang support position includes the main winding rope that is suspended from the main winding sheave when the hanging operation is performed in the overhanging posture, or a suspension provided on the main winding rope and the auxiliary winding sheave. It is a position where interference with the hanging rope provided on the auxiliary rope or the auxiliary rope to be suspended is avoided,
A crane with a jib, wherein the wheel and the auxiliary sheave point sheave are provided so as to be rotatable about a common axis, and the wheel has a larger diameter than the point sheave .

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