JP5984499B2 - Air sheave unit drive mechanism - Google Patents

Description

  The present invention relates to a drive mechanism for an air sheave unit used in a crane work vehicle or the like.

  In a crane work vehicle, an aerial sheave is attached to the jib to raise and lower the jib attached to the tip of the boom. A jib attached to the tip of the boom is raised and lowered by winding a wire between an air sheave and a fixed sheave and winding or feeding the wire with a jib winch (Patent Document 1).

JP-A-11-165984

By the way, the aerial sheave is used together with the jib when the jib is attached to the tip of the boom, but is used in a pair with the fixed sheave. It is good to accommodate.
However, when the aerial sheave is accommodated in the storage unit, the aerial sheave is stored in the storage unit by stopping at the storage unit. As described above, the aerial sheave and the storage portion hit at the winding speed of the winch, so that when the winding speed is high, the aerial sheave and the storage portion hit strongly.
In order to weaken the contact between the aerial sheave and the storage unit, for example, a mechanical switch that detects an aerial sheave immediately before storage is provided, and the winding speed during storage is controlled to be low based on the detection signal of the mechanical switch. It is done. However, since the mechanical switch used for this detection is provided in an exposed state in order to detect an air sheave, there is a possibility that normal detection cannot be performed due to failure or freezing.
For example, if the mechanical switch breaks down or freezes in the detection state, the mechanical switch always outputs a detection signal, and the winding speed of the wire by the winch is always reduced. Work efficiency decreases.

  As described above, in the drive mechanism of the aerial sheave unit used in the crane work vehicle, it is required to weaken the hit when the aerial sheave unit is stored in the storage unit without reducing the work efficiency.

An aerial sheave unit drive mechanism according to the present invention is an aerial sheave unit drive mechanism that raises and lowers a jib attached to the tip of a boom in a crane work vehicle. The aerial sheave unit drive mechanism includes a storage unit that stores the aerial sheave unit, and an aerial sheave unit. A control unit that winds the wire to be rotated with a winch and stores the aerial sheave unit in the storage unit and a detection unit that detects the aerial sheave unit stored in the storage unit are provided, and the control unit is stored in the storage unit When the aerial sheave unit to be detected is detected by the detection unit, whether or not the aerial sheave unit is stored in the storage unit and the jib is removed from the tip of the boom is in a storage state that is a state of a crane work vehicle The winding of the wire by the winch is decelerated when it is in the retracted state, and it is reduced when it is not in the retracted state. Not decelerate the winding wire by, those.

  Preferably, the detection unit may include a mechanical switch that operates by hitting the aerial sheave unit stored in the storage unit, and detects the storage of the aerial sheave unit in the storage unit by the operation of the mechanical switch.

Preferably, the storage unit includes a plurality of sets of guide rails that pivotally support the shaft of the aerial sheave unit, and the aerial sheave unit is pivotally supported by entering from the front end side of the plurality of sets of guide rails. The mechanical switch, which is stored in the storage unit, is disposed at the distal end portion of the guide rail, and detects the aerial sheave unit stored in the storage portion by hitting the aerial sheave unit that has entered the distal end portion of the plurality of sets of guide rails. Good.

  Preferably, the boom of the crane working vehicle is a telescopic boom, and the control unit is configured to operate the crane when the undulation angle of the telescopic boom of the crane working vehicle is smaller than a predetermined value and the length of the telescopic boom is shorter than the predetermined value. It may be determined that the work vehicle is in the retracted state.

  Preferably, it has a control valve provided in the oil supply path to the winch that winds the wire at a speed according to the amount of supplied oil, and the control unit controls the opening of the control valve to control the oil to the winch. It is preferable to reduce the winding speed of the wire by the winch by limiting the supply amount.

  In the present invention, the control unit determines whether or not the crane work vehicle is in the retracted state when the aerial sheave unit stored in the storage unit is detected by the detection unit. And since it is decelerating winding of the wire by a winch in the retracted state, the hit at the time of storing an air sheave unit in a storage part can be weakened. Further, since the winding of the wire by the winch is not decelerated when the state is other than the retracted state, even if, for example, the detection unit breaks down or freezes in the detected state, it is not decelerated. Work efficiency is unlikely to decrease.

1 is an overall configuration diagram of a crane work vehicle in a working posture having a drive mechanism for an air sheave unit according to an embodiment of the present invention. It is a whole block diagram of the crane working vehicle which decomposed | disassembled the luffing jib of FIG. It is explanatory drawing of the mechanical structure of the drive mechanism of an air sheave unit. FIG. 4 is a schematic explanatory diagram of a control system of a drive mechanism of the aerial sheave unit of FIG. 3. It is a flowchart which shows drawing-in control of an air sheave unit. It is a figure explaining the relationship between the relative position of an air sheave unit, and drawing-in speed.

Hereinafter, the drive mechanism of the air sheave unit 14 according to the embodiment of the present invention will be described.
FIG. 1 is an overall configuration diagram of a crane work vehicle 1 in a working posture having a drive mechanism for an aerial sheave unit 14 according to an embodiment of the present invention.
Outriggers 3 are provided on the left and right sides of the vehicle body 2 of the crane work vehicle 1 of FIG. The outrigger 3 extends in the left-right direction of the vehicle body 2 and fixes the vehicle body 2 in a state where it is jacked up from the ground. A swivel unit 4 is turnably provided on the loading platform of the vehicle body 2. The turning unit 4 is provided with, for example, a telescopic boom 5, a hoisting cylinder 6, a crane winch 9, a jib winch 12, and a fixed sheave 13 as a crane mechanism. The telescopic boom 5 is a boom in which multistage booms are connected so as to be telescopic. One end of the telescopic boom 5 is provided on the revolving part 4 so as to be raised and lowered. The hoisting cylinder 6 is provided between the telescopic boom 5 and the turning part 4. The hoisting cylinder 6 expands and contracts by hydraulic pressure. The telescopic boom 5 stands when the hoisting cylinder 6 extends. The telescopic boom 5 in FIG. 1 is in a standing working posture. The telescopic boom 5 falls because the hoisting cylinder 6 is contracted. The telescopic boom 5 shown in FIG. 2, which will be described later, is in a retracted posture in which the telescopic boom 5 is collapsed.

A luffing jib 7, a first mast 85 and a second mast 86 are detachably attached to the tip of the telescopic boom 5. The luffing jib 7 in FIG. 1 is formed by connecting a base jib 80, a first jib 81, a second jib 82, a third jib 83, and a fourth jib 84. The leading end of the fourth jib 84 of the luffing jib 7 and the leading end of the first mast 85 are formed by a first tension rod 95, a second tension rod 96, a third tension rod 97, a fourth tension rod 98, and a fifth tension rod 99. Connected. The tip of the first mast 85 and the tip of the second mast 86 are connected by the first connecting rod 93 and the second connecting rod 94. The aerial sheave unit 14 is connected to the tip of the second mast 86 by a seventh tension rod 92 and a sixth tension rod 91. The luffing jib 7 and the like are assembled at the work site and attached to the tip of the telescopic boom 5. The luffing jib 7 and the like are removed from the tip of the telescopic boom 5 and disassembled at the work site.
Then, the luffing jib 7 can be raised and lowered by moving the air sheave unit 14 in the vertical direction of FIG. For example, when the air sheave unit 14 is moved downward, the leading end of the luffing jib 7 rises upward. The luffing jib 7 rotates around the tip of the telescopic boom 5.

The crane winch 9 is provided behind the hoisting cylinder 6 with respect to the telescopic boom 5 in the revolving part 4. The crane wire 10 wound around the crane winch 9 hangs down from the roller at the tip of the luffing jib 7 through the roller of the second mast 86 and the roller of the first mast 85. A work tool 11 such as a crane member is attached to the tip of the crane wire 10. The work tool 11 moves up and down in FIG. 1 by feeding or winding the crane wire 10.
The jib winch 12 is provided, for example, behind the crane winch 9 in the turning unit 4. The fixed sheave 13 is disposed in the vicinity of the jib winch 12. A jib wire 15 wound around the jib winch 12 is looped between the air sheave unit 14 and the fixed sheave 13. The tip of the jib wire 15 is fixed to the fixed sheave 13, for example. By sending or winding the jib wire 15, the air sheave unit 14 moves upward or downward in FIG. Roughing jib 7 can be raised and lowered.

  FIG. 2 is a diagram for explaining the assembling work and the disassembling work of the luffing jib 7 in the crane work vehicle 1 of FIG. An example of assembly work and disassembly work will be described with reference to FIG.

When the luffing jib 7 is assembled and attached to the tip of the telescopic boom 5, the telescopic boom 5 of the crane work vehicle 1 is tilted as shown in FIG. In this state, the base jib 80, the first mast 85, and the second mast 86 of the luffing jib 7 are attached to the tip of the telescopic boom 5. The tip of the first mast 85 and the tip of the second mast 86 are connected by the first connecting rod 93 and the second connecting rod 94. The seventh tension rod 92, the sixth tension rod 91, and the air sheave unit 14 are connected to the tip of the second mast 86 in order. The jib wire 15 is wound between the air sheave unit 14 and the fixed sheave 13, the jib winch 12 is operated, and the first mast 85 and the second mast 86 are set up.
Next, the first jib 81, the second jib 82, the third jib 83, and the fourth jib 84 are attached to the base jib 80 in order. The first tension rod 95, the second tension rod 96, the third tension rod 97, the fourth tension rod 98, and the fifth tension rod 99 are attached to the first mast 85 in order.
Through the above assembling work, the luffing jib 7 of FIG. 1 is completed.

When disassembling the luffing jib 7 and removing it from the telescopic boom 5, the above operations are performed in reverse. That is, in a state where the telescopic boom 5 of the crane work vehicle 1 is tilted, first, the fourth jib 84, the third jib 83, the second jib 82, and the first jib 81 are sequentially removed. FIG. 2 shows a state where the fourth jib 84, the third jib 83, and the second jib 82 have been removed. Further, the fifth tension rod 99, the fourth tension rod 98, the third tension rod 97, the second tension rod 96, and the first tension rod 95 are removed in order. Thereafter, the base jib 80, the first mast 85, and the second mast 86 are removed from the tip of the telescopic boom 5.
By the way, the disassembled luffing jib 7 and the various tension rods 91 to 99 are loaded on a transport vehicle different from the crane work vehicle 1 and transported. In this case, the air sheave unit 14 used with the luffing jib 7 may also be transported by another transport vehicle. However, the aerial sheave unit 14 is used as a pair with the fixed sheave 13 provided in the crane work vehicle 1. Therefore, it is desirable to provide a storage unit in the crane work vehicle 1 and store the aerial sheave unit 14 in this storage unit.

Next, a drive mechanism having such a storage unit for the aerial sheave unit 14 will be described.
FIG. 3 is an explanatory diagram of the mechanical structure of the drive mechanism of the aerial sheave unit 14 that raises and lowers the luffing jib 7 attached to the tip of the telescopic boom 5 in the crane work vehicle 1 of FIG.

  The air sheave unit 14 has an air sheave 32 as a pulley on which the jib wire 15 is laid. The aerial sheave shaft 33 of the aerial sheave 32 is pivotally supported by one end of a pair of aerial sheave frames 31. The air sheave frame 31 has a long shape longer than the radius of the air sheave 32. A link member 34 is attached to the other end of the pair of aerial sheave frames 31 by a link shaft 35. A link hole 36 for connecting the sixth tension rod 91 is formed at the tip of the link member 34.

The drive mechanism of the aerial sheave unit 14 in FIG. 3 has a winch reel 20 around which the jib wire 15 is wound. A winch shaft 22 of the winch reel 20 is rotatably supported by a pair of winch frames 21. The winch reel 20 rotates at a speed corresponding to the amount of oil supplied from a hydraulic motor 54 described later.
The fixed sheave shaft 25 of the fixed sheave 13 is rotatably supported by a pair of fixed sheave frames 24. The fixed sheave frame 24 is fixed to the winch frame 21 by the connecting frame 23.

The fixed sheave shaft 25 further supports the pair of storage support members 26 so as to be rotatable. The pair of storage support members 26 are long and store the air sheave unit 14 between them. The distal end portion on the free end side of the storage support member 26 is bifurcated. A storage port 29 is formed between the upper guide rail 27 and the lower guide rail 28 by this bifurcated branch.
The aerial sheave shaft 33 of the aerial sheave unit 14 stored between the pair of storage support members 26 enters between the two upper guide rails 27 and the lower guide rails 28 from the front end side thereof and is pivotally supported. The The air sheave unit 14 is stored between the pair of storage support members 26.
The storage support member 26 further detects a wire guide 30 that holds the jib wire 15 that is routed between the fixed sheave 13 and the air sheave unit 14, and the air sheave unit 14 that is stored in the storage support member 26. A mechanical switch 41 is provided.

The mechanical switch 41 is disposed at the tip portion of the upper guide rail 27. The mechanical switch 41 has a rod 41a that is inverted by a pressing force. The rod 41 a protrudes from the upper guide rail 27 toward the lower guide rail 28. When the aerial sheave unit 14 enters between the two upper guide rails 27 and the lower guide rail 28 from the storage port 29, the air sheave unit 14 hits the rod 41a and pushes it down. When the rod 41a is pushed down, the mechanical switch 41 outputs a detection signal.

FIG. 4 is a schematic explanatory diagram of a control system of the drive mechanism of the air sheave unit 14.
The control system in FIG. 4 includes a undulation angle detection unit 42, a boom length detection unit 43, a proximity detection unit 44, and a controller 45. The hydraulic system 50 in FIG. 4 includes a pump 51, a control valve 52, an electromagnetic proportional valve 53, and a hydraulic motor 54.

  The undulation angle detector 42 detects the undulation angle of the telescopic boom 5 and outputs it to the controller 45. The undulation angle detection unit 42 detects the undulation angle of the telescopic boom 5 as an angle based on the horizontal direction of the vehicle, for example. The undulation angle of the telescopic boom 5 may be calculated from the expansion / contraction length of the undulation cylinder 6.

  The boom length detector 43 detects the length of the telescopic boom 5 and outputs it to the controller 45. The length of the telescopic boom 5 may be calculated from the control data of the telescopic boom 5.

The proximity detector 44 detects a proximity state between the aerial sheave unit 14 and the pair of storage support members 26 that store the air sheave unit 14. The proximity detection unit 44 is connected to the mechanical switch 41.
The proximity detection unit 44 outputs a detection signal to the controller 45 when the rod 41a of the mechanical switch 41 is in a collapsed state.

The controller 45 is, for example, a one-chip microcomputer. A CPU (Central Processing Unit) of a one-chip microcomputer reads and executes a program stored in a memory. Thus, the storage posture determination unit 46 and the jib winch winding deceleration determination unit 47 are realized in the controller 45.
The controller 45 controls the overall operation of the crane work vehicle 1.

The storage posture determination unit 46 determines whether or not the telescopic boom 5 is in the storage posture.
The retracted posture determination unit 46 has, for example, the telescopic boom 5 detected by the boom length detecting unit 43 when the hoisting angle of the telescopic boom 5 detected by the hoisting angle detecting unit 42 is not more than a predetermined value, for example, 15 degrees or less. Is less than a predetermined value, for example, less than or equal to the total contracted length of the telescopic boom 5, it is determined that the telescopic boom 5 is in the retracted position.
When at least one of the conditions is not satisfied, the storage posture determination unit 46 determines that the telescopic boom 5 is in the working posture. The working posture is different from the retracted posture. However, depending on the work environment, the work may be performed in a work posture that is not different from the retracted posture. In this case, the posture of the telescopic boom 5 may temporarily become a retracted posture or a substantially retracted posture during work.

The jib winch winding deceleration determination unit 47 determines whether or not to reduce the winding speed of the jib wire 15 by the jib winch 12. Since the raising / lowering angle of the luffing jib 7 with respect to the telescopic boom 5 changes due to the winding of the jib wire 15, reducing the winding speed of the jib winch 12 slows the control speed of the raising / lowering angle of the luffing jib 7.
For example, when the retractable posture determination unit 46 determines that the telescopic boom 5 is in the stored posture and the detection signal is input from the proximity detection unit 44, the jib winch winding deceleration determination unit 47 decreases the winding speed. Judge that. In other cases, it is determined that the winding speed is not slowed down.
When it is determined that the winding speed is to be slowed down, the jib winch winding deceleration determination unit 47 outputs a control signal for restricting the electromagnetic proportional valve 53. When it is determined that the winding speed is not slowed down, the jib winch winding deceleration determination unit 47 outputs a control signal for returning the electromagnetic proportional valve 53 to the original state.

The electromagnetic proportional valve 53 is provided in an oil circulation path including the pump 51, the control valve 52, and the hydraulic motor 54. In the electromagnetic proportional valve 53, the opening degree of the valve is controlled by a control signal.
When the electromagnetic proportional valve 53 is throttled, the flow rate of the oil circulated in the hydraulic system 50 of FIG. 4 decreases. The amount of oil supplied to the hydraulic motor 54 decreases, the rotation of the hydraulic motor 54 decreases, and the rotation speed of the winch reel 20 also decreases. The pulling speed of the jib wire 15 decreases.

FIG. 5 is a flowchart showing the pull-in control of the air sheave unit 14 by the control system of FIG.
In FIG. 5, the controller 45 starts pull-in control of the air sheave unit 14 (step ST1).
After starting the pull-in control of the aerial sheave unit 14, the jib winch winding deceleration determination unit 47 of the controller 45 determines whether or not a detection signal is input from the proximity detection unit 44 (step ST2).
When the detection signal is not input from the proximity detection unit 44, the jib winch winding deceleration determination unit 47 of the controller 45 determines that the winding speed is not slowed down and continues winding at the normal speed (step ST3).

When a detection signal is input from the proximity detection unit 44, the jib winch winding deceleration determination unit 47 of the controller 45 further acquires the determination result of the storage posture determination unit 46.
The storage posture determination unit 46 determines whether or not the telescopic boom 5 is in the storage posture based on the detection results of the undulation angle detection unit 42 and the boom length detection unit 43 (step ST4).

For example, when the telescopic boom 5 is in the retracted position as shown in FIG. 2, the retractable attitude determination unit 46 determines that the telescopic boom 5 is in the retracted position. The jib winch winding deceleration determination unit 47 determines to decrease the winding speed based on the input of the detection signal from the proximity detection unit 44 (step ST5).
The jib winch winding deceleration determination unit 47 of the controller 45 outputs a control signal for restricting the valve to the electromagnetic proportional valve 53. The winding speed of the jib wire 15 by the winch reel 20 decreases.

  For example, when the telescopic boom 5 is in the working posture as shown in FIG. 1, the retractable posture determination unit 46 determines that the telescopic boom 5 is not in the retracted posture, and the jib winch winding deceleration determination unit 47 detects the detection signal of the proximity detection unit 44. It is determined that the winding speed is not slowed despite the fact that is input (step ST3). The jib winch winding deceleration determination unit 47 continues winding at the normal speed.

Next, the controller 45 determines whether or not to stop the pull-in control of the air sheave unit 14 (step ST6).
The controller 45 continues the process of FIG. 5 during the execution of the pull-in control. The controller 45 repeatedly determines whether it is necessary to decelerate the winding by the jib winch 12 during execution of the pull-in control, and executes the deceleration of the winding if necessary. In addition, when it is no longer necessary to reduce the winding, the winding speed is returned to the normal winding speed.
When stopping the pull-in control, the controller 45 ends the process of FIG.

FIG. 6 is a diagram for explaining the relationship between the relative position of the aerial sheave unit 14 and the retraction speed under the control of FIG. FIG. 6A shows a state in which the aerial sheave unit 14 is separated from the pair of storage support members 26 constituting the storage portion. FIG. 6B shows a state where the aerial sheave unit 14 is in contact with the rod 41 a of the mechanical switch 41. FIG. 6C shows a state where the air sheave unit 14 is stored between the pair of storage support members 26. On the right side of FIGS. 6A to 6C, the winding speed by the jib winch 12 during storage and the winding speed by the jib winch 12 during work are shown.
At the time of storage, the winding speed when the aerial sheave unit 14 is pulled into the storage section is a normal speed in the section from the separation position in FIG. 6A to the detection position in FIG. 6B. In the section from the detection position in FIG. 6 (B) to the storage position in FIG. 6 (C), the vehicle is decelerated.
On the other hand, for example, while the telescopic boom 5 is standing as shown in FIG. 1, not only the section from FIG. 6 (A) to FIG. 6 (B) but also FIG. 6 (B) to FIG. 6 (C). Even in the section up to, the winding speed at the time of drawing is always maintained at a normal speed. Not slowed down.

As described above, in this embodiment, the air sheave unit 14 can be stored in the storage portion between the pair of storage support members 26 by winding the jib wire 15 with the jib winch 12. The aerial sheave unit 14 can be transported while being fixed so as not to fall off the vehicle body 2 of the crane work vehicle 1.
In the present embodiment, when the storage of the aerial sheave unit 14 in the storage unit is detected, it is determined whether or not the telescopic boom 5 of the crane work vehicle 1 is in the storage position. Then, the winding of the jib wire 15 by the jib winch 12 is decelerated only when in the retracted posture. Therefore, the hit at the time of storage of the air sheave unit 14 and the pair of storage support members 26 can be weakened.
In the present embodiment, when the telescopic boom 5 is not in the retracted position, the winding of the jib wire 15 by the jib winch 12 is not decelerated. Even if the mechanical switch 41 detects that the air sheave unit 14 is stored in the storage unit, the winding speed of the jib winch 12 is maintained at a normal speed. When the telescopic boom 5 of the crane work vehicle 1 is not in the retracted position, for example, in a working position, the jib winch 12 winds the jib wire 15 at a normal speed. Even if the aerial sheave unit 14 is close to the storage support member 26 during the work, the work can be performed efficiently.

In the present embodiment, the storage of the air sheave unit 14 is detected by the mechanical switch 41. Since the mechanical switch 41 is installed so as to be exposed to the outside in the storage support member 26, there is a possibility that the mechanical switch 41 may be broken or frozen and cannot be normally detected. However, in this embodiment, the retracted posture of the telescopic boom 5 of the crane work vehicle 1 is determined, and deceleration control is executed only when the retracted posture is in the retracted posture. Therefore, even when the mechanical switch 41 is maintained in the detection state due to failure or freezing, the winding speed of the jib wire 15 can be maintained at a normal speed.
In particular, the mechanical switch 41 is disposed at the tip portion of the upper guide rail 27 of the storage support member 26. Therefore, the mechanical switch 41 detects the storage of the aerial sheave unit 14 in the storage portion at the timing when the aerial sheave unit 14 starts to enter the tip portion of the upper guide rail 27. Before the storage of the air sheave unit 14 is completed, the storage can be detected and the winding speed of the jib wire 15 can be reduced. It is possible to decelerate before the storage of the air sheave unit 14 is completed so that the air sheave unit 14 does not hit the storage support member 26 at a normal speed.

  The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications or changes can be made without departing from the scope of the invention.

DESCRIPTION OF SYMBOLS 1 Crane work vehicle, 5 Telescopic boom (boom), 7 Roughing jib (jib), 12 Jib winch (winch), 14 Aerial sheave unit, 15 Jib wire (wire), 26 Storage support member (storage part), 27 Upper guide rail (guide) Rail), 28 lower guide rail (guide rail), 33 aerial sheave shaft (axis), 41 mechanical switch (detection unit), 44 proximity detection unit (detection unit), 45 controller (control unit), 53 electromagnetic proportional valve (control) valve)

Claims (5)

A drive mechanism for an aerial sheave unit for raising and lowering a jib attached to the tip of a boom in a crane work vehicle,
A storage unit for storing the aerial sheave unit;
A control unit that winds a wire wound around the aerial sheave unit with a winch, and stores the aerial sheave unit in the storage unit;
A detection unit for detecting the aerial sheave unit stored in the storage unit;
Provided,
When the aerial sheave unit stored in the storage unit is detected by the detection unit, the control unit stores the aerial sheave unit in the storage unit and removes the jib from the tip of the boom. It is determined whether or not the crane working vehicle is in the retracted state. When the crane work vehicle is in the retracted state, the winding of the wire by the winch is decelerated, and when it is not in the retracted state, the winding of the wire by the winch is decelerated. do not do,
An aerial sheave unit drive mechanism. A drive mechanism for an air sheave unit according to claim 1,
The detection unit includes a mechanical switch that operates by hitting the aerial sheave unit stored in the storage unit, and detects storage of the aerial sheave unit in the storage unit by an operation of the mechanical switch.
An aerial sheave unit drive mechanism. A drive mechanism for an air sheave unit according to claim 2,
The storage portion includes a plurality of sets of guide rails that support the shaft of the aerial sheave unit,
The aerial sheave unit is stored in the storage unit by entering from the front end side of the plurality of guide rails and being pivotally supported.
The mechanical switch is disposed at a distal end portion of the guide rail, and detects the aerial sheave unit stored in the storage portion by hitting the aerial sheave unit that has entered the distal end portions of the plurality of sets of guide rails. ,
An aerial sheave unit drive mechanism. A drive mechanism for an air sheave unit according to claim 1,
The boom of the crane work vehicle is a telescopic boom,
The control unit determines that the crane work vehicle is in a retracted state when the undulation angle of the telescopic boom of the crane work vehicle is smaller than a predetermined value and the length of the telescopic boom is shorter than a predetermined value.
An aerial sheave unit drive mechanism. A drive mechanism for an air sheave unit according to claim 1,
A control valve provided in an oil supply path to the winch that winds the wire at a speed according to the amount of oil supplied;
The control unit reduces the winding speed of the wire by the winch by limiting the amount of oil supplied to the winch by controlling the opening of the control valve.
An aerial sheave unit drive mechanism.

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