JP2006199392A - Crane having live mast - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent interference of a derricking rope and a swing body when a live mast is forwardly inclined in arrangement work. <P>SOLUTION: The crane having the live mast is provided with a derricking drum 8 mounted on the swing body 2; a rope sheave 11 supported on a rear end of the swing body 2; a bail sheave 13 provided movably around the periphery of the rope sheave 11 through an arm turnable in the fore-and-aft direction above the swing body 2; a bridle 12 provided on a distal end of the live mast 4; and bail movement restriction means 22a, 32 for restricting the movement of the bail sheave 13 such that the derricking rope 8a does not interfere with an upper part of the swing body 2 when the derricking rope 8a wound on the derricking drum 8 and laid between the bridle 12 and the bail sheave 13 via the rope sheave 11 is paid out and the live mast 4 is forwardly inclined. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a crane having a live mast that is pivotally supported on a swivel body so as to be able to move up and down.

  2. Description of the Related Art Conventionally, a crane having a live mast that is pivotally supported by a revolving body behind a boom so as to be movable up and down is known (for example, see Patent Document 1). In this crane, the tip of the boom and the tip of the live mast are connected with a pendant rope, and a rope sheave and a bail sheave are provided adjacent to the tip of the mast standing on the revolving structure, and a bridle is attached to the tip of the live mast. Provide. Then, the hoisting rope wound around the hoisting drum is hung between the bridle and the bail sheave via the rope sheave, and the live mast is rotated and the boom is raised and lowered by winding or feeding the hoisting rope.

JP-A-9-194190 (FIG. 13)

  By the way, in recent years, cranes with high lifting ability have been developed, and the ground clearance of the swivel body is high. Therefore, in order to cope with the transportation regulation in the height direction, it is necessary to make the height of the rope sheave relatively low with respect to the revolving structure. However, if the height of the rope sheave is lowered, the hoisting rope may interfere with the upper part of the revolving body when the live mast is rotated forward during the crane disassembly work.

The present invention has a live mast that is pivotally supported by a swinging body at the rear of the working boom, is raised with the boom at the rear of the working boom at the time of crane work, and is tilted forward of the swinging body at the time of setup work. It is a crane and can move around the rope sheave through a hoisting drum mounted on the swivel body, a rope sheave supported on the rear end of the swivel body, and an arm that can be rotated in the front-rear direction above the swivel body. The bail sheave provided at the front of the live mast, the bridle provided at the tip of the live mast, and the hoisting rope that is wound around the hoisting drum and passed between the bridle and the bail sheave through the rope sheave, A bail movement restricting means for restricting the movement of the bail sheave so that the hoisting rope does not interfere with the upper part of the revolving structure when tilted to the right. To.
In addition, the present invention is characterized by comprising interference preventing means for preventing the hoisting rope stretched from the rope sheave to the bridle from interfering with the bail sheave when the hoisting rope is extended and the live mast is tilted forward.
A guide roller that can be moved around the rope sheave via an arm that can be rotated in the front-rear direction above the swivel body, and a roller movement that pushes the hoisting rope upward by the guide roller by restricting the movement of the guide roller. The interference preventing means can be constituted by the limiting means.
It is preferable that the movement of the bail sheave is restricted by the bail movement restriction means after the movement of the guide roller is restricted by the roller movement restriction means.
A biasing means for biasing the arm for supporting the guide roller to the arm for supporting the bail sheave may be provided.

  According to the present invention, when the hoisting rope is drawn out and the live mast is tilted forward, the movement of the bail sheave is restricted so that the hoisting rope does not interfere with the upper part of the revolving structure, or the rope sheave is stretched from the bridle. The hoisting rope was prevented from interfering with the bail sheave. Thereby, even when the height of the rope sheave is relatively lowered, the undulating rope does not interfere with the upper part of the revolving structure or the bail sheave, and the transportation regulation can be easily dealt with.

Hereinafter, an embodiment of a crane according to the present invention will be described with reference to FIGS.
1 and 2 are side views of a crane according to the present embodiment. 1 shows the working posture of the crane, and FIG. 2 shows the exploded posture.

  As shown in FIG. 1, a swiveling body 2 is mounted above the traveling body 1 so as to be turnable. A lattice-type boom 3 is pivotally supported at the front part of the swing body 2 so as to be pivotable in the front-rear direction, and the live mast 4 is pivotable in the front-rear direction through the top of the swing body 2 behind the boom 3. Is supported. A driver's cab 5 is mounted on the front part of the revolving body frame 2a, a main winding drum 6, an auxiliary winding drum 7 and an undulating drum 8 are mounted on the rear side, and a counterweight 9 is mounted on the rear end of the revolving body frame 2a. It is installed. A main winding rope 6a is wound around the main winding drum 6, and the main winding rope 6a is connected to the hook 10 via a sheave 11 at the tip of the boom. When the main winding rope 6a is wound or unwound by driving the main winding drum 6, the hook 10 moves up and down.

  The hoisting drum 8 is disposed at the rear end portion of the revolving unit 2, and a rope sheave 11 is provided obliquely upward on the rear side of the hoisting drum 8. A hoisting rope 8a is wound around the hoisting drum 8, and the hoisting rope 8a is routed between a bridle 12 provided at the tip of the live mast and a bail sheave 13 near the rope sheave via a rope sheave 11. The tip of the boom and the tip of the live mast are connected by a pendant link 14, and when the hoisting rope 8a is wound or fed out by driving the hoisting drum 8, the live mast 4 rotates and the boom 3 rises and lowers.

  The crane shown in FIGS. 1 and 2 has a high lifting capacity, and the diameters of the drums 6 to 8 are also large. Therefore, it is necessary to make the traveling body 1 and the revolving structure 2 strong, and the height of the revolving structure 2 is necessarily high. In this case, if the mast is erected on the revolving structure and the rope sheave 11 is attached, there is a possibility that transportation regulations cannot be dealt with. Therefore, in the present embodiment, as shown in FIG. 2 and FIG. 4 described later, the rope sheave 11 is directly attached to the bracket 2b provided at the upper end portion of the revolving body frame 2a.

  On the other hand, when the rope sheave 11 is provided as described above, the height of the rope sheave 11 with respect to the revolving structure 2 is relatively low. Therefore, in the disassembled posture, the hoisting rope 8a hung between the bridle 12 and the bail sheave 13 may interfere with the covers 2c of the drums 6 and 7 protruding from the upper part of the revolving unit 2, the operator cab 5, and the like. Further, the hoisting rope 8a stretched from the rope sheave 11 to the bridle 12 may interfere with the bail sheave 13 made of resin, for example. In order to avoid this, in this embodiment, the rope support portion is configured as follows.

  FIG. 3 is a diagram showing the configuration of the rope support portion at the rear end of the revolving unit, and FIG. 4 is a top view of FIG. 3 (view IV view of FIG. 2). A pair of left and right brackets 2b are provided at the upper end of the swing body frame 2a so as to be spaced apart from each other in the width direction (left and right direction) of the swing body 2. A rotating shaft 21 is supported on the bracket 2b, and a pair of left and right rope sheaves 11 are rotatably supported on the rotating shaft 21. A pair of left and right bail arms 22 are supported at both ends of the rotating shaft 21 so as to be rotatable in the front-rear direction within a vertical plane, and a plurality of bail sheaves 13 are supported at the tip of the bail arm 22 so as to be rotatable. The hoisting rope 8a passing through the rope sheave 11 is routed a plurality of times between the bail sheave 13 and the bridle 12 via the bridle 12, and is connected to the sheave 23 in the vicinity of the bail sheave.

  Further, a roller arm 24 is supported on the rotary shaft 21 so as to be rotatable in the front-rear direction within a vertical plane, and a substantially cylindrical guide roller 25 is rotatably supported at the tip of the roller arm 24. The width of the guide roller 25 in the left-right direction is substantially equal to the range in which the bail sheaves 13 are juxtaposed in the left-right direction. Further, an arm 26 is rotatably supported on the rotary shaft 21, and a roller 27 provided at the tip of the arm functions as a detachment stopper for the hoisting rope 8 a from the rope sheave 11.

  FIG. 5 is a cross-sectional view taken along line VV in FIG. A spring 31 is interposed inside the arms 22 and 24, and the roller arm 24 and the bail arm 22 are connected by the spring 31. As a result, a spring force that always approaches the bail arm 22 acts on the roller arm 24 as shown in the figure, and the roller arm 24 can rotate integrally with the bail arm 22. Protrusions 22a and 24a are provided on the base end side edges of the arms 22 and 24, respectively, and a stopper 32 is fixed to the revolving body frame 2a corresponding to the protrusions 22a and 24a.

  The protruding portions 22a and 24a are provided so that the lower end surface of the protruding portion 24a is positioned below the lower end surface of the protruding portion 22a in a state where the arms 22 and 24 approach each other and rotate forward as illustrated. It is done. As a result, when the arms 22 and 24 are rotated forward, the lower end surface of the protrusion 24a comes into contact with the stopper 32 first, and the roller arm 24 is prevented from further rotating forward. When the bail arm 22 is further rotated forward, the arms 22 and 24 are separated from each other against the spring force as shown in FIG. When the lower end surface of the protrusion 22a comes into contact with the stopper 32, further forward rotation of the bail arm 22 is prevented. That is, the roller arm 24 is prevented from rotating at an angular position larger than the bail arm 22, and the bail arm 22 can be rotated to an angular position smaller than the roller arm 24 (a state closer to the revolving body 2). ing.

Next, main operations of the crane according to the present embodiment will be described.
When carrying out the crane work, the boom 3 is attached to the revolving structure 2 and the crane posture is as shown in FIG. In this state, when the hoisting drum 8 is driven and the hoisting rope 8a is wound up or fed out, the live mast 4 moves up and down behind the boom 3, whereby the boom 3 moves up and down. Further, the position of the bridle 12 is moved by the rotation of the live mast 4, and accordingly, the bail sheave 13 moves around the rope sheave 11 through the arm 22. In this case, since the roller arm 24 is biased by the bail arm 22 by the spring force, the roller arm 24 and the guide roller 25 approach the bail arm 22 and retreat from the movement locus of the hoisting rope 8a, and the hoisting rope 8a. Does not contact the guide roller 25. Therefore, an excessive load on the hoisting rope 8a during crane operation does not act on the guide roller 25, and the guide roller 25 can be protected.

  On the other hand, when the crane is disassembled (at the time of setup work) after the completion of the crane work, the hoisting rope 8a is fed out and the live mast 4 is rotated forward as shown in FIG. In this case, the bail arm 22 rotates forward as the live mast 4 rotates forward, and the roller arm 24 also rotates forward due to the biasing force of the spring 31. When the forward inclination angle of the live mast 4 with respect to the horizontal plane reaches a predetermined value, the lower end surface of the protrusion 24a comes into contact with the stopper 32 as shown in FIG. 5, and the roller arm 24 is prevented from rotating forward. . Thereby, the downward movement of the guide roller 25 is restricted.

  When the live mast 4 is further rotated forward, only the bail arm 22 is rotated forward, leaving the roller arm 24 in that position, and the arms 22 and 24 are separated from each other. When the forward inclination angle of the live mast 4 reaches a predetermined angle that is further smaller than the predetermined value described above, the lower end surface of the projection 22a comes into contact with the stopper 32 as shown in FIG. Is prevented from rotating. Thereby, the downward movement of the bail sheave 13 is restricted, and the hoisting rope 8a can be prevented from interfering with the cover 2c on the upper part of the revolving structure 2 and the cab 5. At this time, the hoisting rope 8 a that has moved downward as the live mast 4 tilts forward is prevented from further moving downward by the guide roller 25, so that the gap with the bail sheave 13 is widened, and interference with the bail sheave 13 is caused. Is prevented. Since the load acting on the hoisting rope 8a during the disassembling work is small, the hoisting rope 8a can be supported by the guide roller 25 without any problem.

  Note that the crane according to the present embodiment has a function of automatically stopping the driving of the hoisting drum 8a when the forward inclination angle of the live mast 4 reaches a predetermined automatic stop angle (for example, 10 °). This automatic stop angle is set smaller than the angle at which the protrusions 22a, 24a abut against the stopper 32, and the boom 3 is removed from the revolving structure 2 in a state where the automatic stop is activated.

According to the above embodiment, the following effects can be obtained.
(1) A bail arm 22 is provided so as to be rotatable in the front-rear direction within a vertical plane with a rotating shaft 21 that supports the rope sheave 11 as a fulcrum, and a protrusion 22a is provided at an edge of the bail arm 22, and the protrusion 22a By making contact with the stopper 32, the forward rotation of the bail arm 22 is restricted. This restricts the downward movement of the bail sheave 13 when the live mast 4 is tilted forward, and when the position of the rope sheave 11 is relatively lowered, the hoisting rope 8a is provided with the cover 2c on the upper part of the revolving structure and the cab 5 Can be prevented from interfering with.

(2) A roller arm 24 is provided so as to be pivotable in the front-rear direction in the vertical plane with the rotary shaft 21 that supports the rope sheave 11 as a fulcrum, the roller arm 24 and the bail arm 22 are connected by a spring 31, and the roller arm 24 A protrusion 24 a is provided at the edge of the roller 24, and the protrusion 24 a abuts against the stopper 32 to restrict the forward rotation of the roller arm 24. As a result, the downward movement of the guide roller 25 is restricted, and the hoisting rope 8a from the rope sheave 11 to the bridle 12 is pushed up by the guide roller 25, so that the interval between the hoisting rope 8a and the rope sheave 11 is widened. Therefore, it is possible to prevent the hoisting rope 8a passing through the rope sheave 11 from interfering with the bail sheave 13 before reaching the bridle 12. As a result, only a normal load acts on the bail sheave 13, and damage to the bail sheave 13 can be prevented when the bail sheave 13 is made of resin for weight reduction.

(3) Since the protruding portion 22a of the bail arm 22 contacts the stopper 32 after the protruding portion 24a of the roller arm 24 contacts the stopper 32, interference between the hoisting rope 8a, the upper part of the revolving unit, and the bail sheave 13 is caused simultaneously. Can be prevented.
(4) Since the bail arm 22 and the roller arm 24 are connected by the spring 31, it is possible to prevent the guide roller 25 from interfering with the hoisting rope 8a during crane work. Therefore, since only a relatively small load is applied to the guide roller 25 during the setup operation, it is not necessary to increase the strength of the guide roller 25 and the design is easy.
(5) Since it is not necessary to increase the diameter of the rope sheave 11 in order to avoid interference between the hoisting rope 8a and the bail sheave 13, it is possible to easily cope with transportation restrictions.
(6) Since it is not necessary to reduce the diameter of the bail sheave 13, the rope life is not deteriorated.
(7) Since the forward tilt angle of the live mast 4 can be reduced, the setup work such as attachment / detachment of the pendant rope 14 can be easily performed.

  In the above embodiment, the rope sheave 11 is directly attached to the revolving body frame 2a, but it may be attached via a mast. If the bail sheave 13 and the guide roller 25 are provided so as to be movable around the rope sheave 11 via an arm that can pivot in the front-rear direction, a bail sheave support arm (bail arm 22) and a guide roller support arm (roller arm 24) are provided. ) Is not limited to that described above. Although the protrusion 22a is provided on the bail arm 22 and the protrusion 22a abuts against the stopper 32, the movement of the bail sheave 13 is restricted. However, other bail movement restricting means may be used. Although the protrusion 24a is provided on the roller arm 24 and the protrusion 24a abuts against the stopper 32, the movement of the guide roller 25 is limited. However, other roller moving means may be used. Further, other interference preventing means for preventing the hoisting rope 8a from interfering with the bail sheave 13 may be used.

  In the above-described embodiment, the protrusions 22a and 24a are provided on the arms 22 and 24, respectively, and the movement of the bail sheave 13 is limited after the movement of the guide roller 25 is limited, but either the guide roller 25 or the bail sheave 13 is limited. You may make it restrict | limit the movement of only one side. Although the roller arm 24 is urged toward the bail arm 22 by the spring 31, the urging means is not limited to this. That is, as long as the features and functions of the present invention can be realized, the present invention is not limited to the crane according to the embodiment. The above description is merely an example, and when interpreting the invention, there is no limitation or restriction on the correspondence between the items described in the embodiment and the items described in the claims.

It is a side view of the crane which concerns on embodiment of this invention, and is a figure which shows a working posture. It is a side view of the crane which concerns on embodiment of this invention, and is a figure which shows a disassembly attitude | position. The figure which shows the principal part structure of the crane which concerns on embodiment of this invention. FIG. 4 is a top view of FIG. 3 (an arrow IV view of FIG. 2). The figure which shows an example of the operation | movement at the time of tilting a live mast forward. The figure which shows an example of the operation | movement at the time of making a live mast lean forward from the state of FIG.

Explanation of symbols

2 Revolving body 3 Boom 4 Live mast 8 Hoisting drum 8a Hoisting rope 11 Rope sheave 12 Bridle 13 Bail sheave 22 Bail arms 22a and 24a Protruding part 24 Roller arm 25 Guide roller 31 Spring 32 Stopper

Claims (5)

A crane having a live mast that is pivotally supported by the revolving structure, moves up and down with the boom behind the working boom during crane work, and tilts forward of the revolving structure during setup work,
An undulation drum mounted on the revolving structure;
A rope sheave supported by the rear end of the revolving structure;
A bail sheave provided so as to be movable around the rope sheave through an arm that is pivotable in the front-rear direction above the revolving structure;
A bridle provided at the tip of the live mast;
When the hoisting rope that is wound around the hoisting drum and is wound between the bridle and the bail sheave via the rope sheave is tilted forward, the hoisting rope is moved to the swivel body. A crane having a live mast, further comprising bail movement limiting means for limiting movement of the bail sheave so as not to interfere with an upper portion of the bail. A crane having a live mast that is pivotally supported by the revolving structure, moves up and down with the boom behind the working boom during crane work, and tilts forward of the revolving structure during setup work,
An undulation drum mounted on the revolving structure;
A rope sheave supported by the rear end of the revolving structure;
A bail sheave provided so as to be movable around the rope sheave through an arm that is pivotable in the front-rear direction above the revolving structure;
A bridle provided at the tip of the live mast;
When the hoisting rope wound around the hoisting drum and wound between the bridle and the bail sheave via the rope sheave is extended and the live mast is tilted forward, the rope sheave is stretched from the rope sheave to the bridle. A crane having a live mast, comprising interference preventing means for preventing a suspended undulating rope from interfering with the bail sheave. In the crane which has the live mast of Claim 2,
The interference preventing means is
A guide roller provided so as to be movable around the rope sheave via an arm that is pivotable in the front-rear direction above the revolving structure;
A crane having a live mast, comprising: roller movement restriction means for restricting the movement of the guide roller to push the hoisting rope upward by the guide roller. In the crane which has the live mast of Claim 3,
Further comprising bail movement limiting means for limiting the movement of the bail sheave so that the hoisting rope does not interfere with the upper part of the revolving structure,
The crane having a live mast, wherein the movement of the bail sheave is restricted by the bail movement restriction means after the movement of the guide roller is restricted by the roller movement restriction means. In the crane which has the live mast of Claim 3 or 4,
A crane having a live mast comprising biasing means for biasing the arm for supporting the guide roller to the arm for supporting the bail sheave.

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