JP2006137504A - Storage release controller for crane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage release controller for a crane with improved operation properties by automatically performing storage release control for returning a crane from storage attitude (running attitude) to working attitude by simple operation. <P>SOLUTION: A controller 31 of this storage release controller outputs a valve switching signal for switching a rising and falling-down control valve 17 to a rising and elevation side and a winch control valve 18 to a winding-down side based on an operation signal of a storage release indicating switch 29 for indicating storage release control for returning the crane to the working attitude from the storage attitude, drives the rising and elevation movement of a telescopic boom 7 and the winding-down movement of a hook block 10 simultaneously, outputs a valve switching signal for switching an expansion and contraction control valve 16 to an elongation side after shutting off a valve switching signal to the rising and falling-down control valve 17 based on an operation signal of an elongation operation means 26 during control, and drives the elongation movement of the telescopic boom 7 and the winding-down movement of the hook block 10 simultaneously. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention hangs a hook block so that it can be wound up and down freely at the tip of a telescopic boom that can be raised and retracted, and retracts the telescopic boom in the retracted state and collapses the hook block along the lower surface of the tip of the telescopic boom. The present invention relates to a storage release control device for a crane configured to be stored in a hook storage position.

  A crane configuration that hangs a hook block on the tip of a telescopic boom that can be raised and lowered and that can be wound and unwound, and that carries the cargo on the hook block is located between the truck cab and the loading platform. An example of a vehicle-mounted crane that is mounted on a chassis frame and used mainly for loading and unloading loads on a loading platform will be described.

  As shown in FIG. 2, the vehicle-mounted crane A is mounted on a chassis frame 1a positioned between the cab 2 and the loading platform 3 of the truck 1 and includes outrigger devices 4 and 4 that can be installed by extending left and right. A crane base 5, a swing post 6 that is pivotably mounted on the crane base 5, and is pivotally supported on the upper part of the swing post 6 so as to be raised and lowered. , 7-3... Can be moved up and down from the distal end portion 7a of the telescopic boom by a telescopic boom 7 in which the telescopic booms 7 are sequentially inserted and retracted, a wire rope 9 fed from a winch device 8 attached to the swivel post 6 or the proximal boom 7-1. A suspended hook block 10 for loading and unloading, a hoisting cylinder 11 interposed between the swivel post 6 and the proximal boom 7-1 and driving the telescopic boom 7 to move up and down, and built in the telescopic boom 7 with respect to the proximal boom 7-1 Tip boom 7-2, 7- 3. Consists of a telescopic cylinder 12 that extends and retracts. Reference numeral 13 denotes a turning drive means for turning the turning post 6 (the telescopic boom 7).

  14 is a switching control valve for controlling the pressure oil discharged from the hydraulic pump 15 to supply and discharge to the swing driving means 13 and drive the swing post 6 to turn right or left. An expansion / contraction control valve 17 that supplies and discharges the expansion / contraction cylinder 12 to drive the expansion / contraction boom 7 to extend / contract, and similarly controls the pressure oil to supply / discharge the expansion / contraction cylinder 11 to drive the expansion / contraction boom 7 up or down. Similarly, the undulation control valve 18 is a winch control valve for switching and controlling the pressure oil to supply and discharge the winch device 8 and to drive the hook block 10 up or down. Reference numeral 19 denotes a relief valve interposed in the discharge oil passage 20 of the hydraulic pump 15. An unloading solenoid valve 21 is interposed in the vent oil passage 19a of the relief valve 19, and by closing the solenoid valve 21, the set pressure of the relief valve 19 is controlled to the normal driving pressure, and the valve is opened. By doing so, the set pressure of the relief valve 19 is controlled to the unloaded state.

  Also, this type of vehicle-mounted crane A is provided with a known overwinding prevention device 22 that prevents the hook block 10 from being rolled up until it abuts against the boom tip 7a during the operation to prevent an overwinding state. ing. The overwinding prevention device 22 suspends an overwinding detection weight 22c via a detection wire rope 22b of a predetermined length from an overwinding detection switch 22a attached to the boom tip 7a as shown in FIG. When the hook block 10 is wound over the overwinding position U (winding upper limit position), the hook block 10 abuts against the overwinding detection weight 22c, and the supporting force of the detection wire rope 22b is excessively decreased. The winding detection switch 22a is configured to detect. Then, the unloading solenoid valve 21 is activated during each of the hoisting operation, boom raising operation, and boom extending operation, which is the operation that promotes the overwinding state by the overwinding detection signal, and the relief valve 19 is unloaded. And the crane drive (hook hoisting, boom raising and boom extension driving) is stopped. This prevents the hook block 10 from being overwound. Note that the overwinding prevention device 22 does not restrict hook lowering, boom overturning, and boom reduction driving that do not promote an overwinding state as avoidance movements to the safe side.

  Further, reference numeral 23 denotes a hook storage along the lower surface of the telescopic boom tip 7a so that the hook block 10 is not swung due to vibration during running when the crane is moved and moved, and the boom tip 7a is not damaged. A hook storage device for storing in a position. The hook storage device 23 drives the hook block 10 in a state where the restriction of the hook hoisting motion by the overwinding prevention device 22 is released, and the hook block 10 is directly connected to the boom tip 7a or the hook storage link 23a or the like. 2 is configured to be stored in the hook storage position as shown by the solid line in FIG. As a result, the swinging of the hook block 10 is restricted, and damage to the boom tip can be prevented.

  The vehicle-mounted crane A configured as described above is configured to hang a load on the hook block 10 with the outrigger devices 4 and 4 extended to the left and right and support the crane, and switch the turning control valve 14 to turn. The drive means 13 is swiveled, and the expansion / contraction control valve 16 is switched to expand / contract the expansion / contraction cylinder 12, and the undulation control valve 17 is switched to drive the undulation cylinder 11 to undulate. After moving 7a to the upper position of the load, the winch control valve 18 is switched and the winch device 8 is driven to wind up and down to raise and lower the hook block 10 to an arbitrary height to perform crane work. Yes.

  On the other hand, when the operation is completed and the crane is stored in the traveling posture, the swing control valve 14 is switched and the telescopic boom 7 is moved to a predetermined storage swing position (usually provided at the rear position of the truck 1). After the turning, the retractable control valve 16 is switched and the telescopic boom 7 is contracted to the minimum, and the hoisting control valve 17 is switched and the telescopic boom 7 is collapsed to the retracted position as shown by the solid line in FIG. Next, the winch control valve 18 is switched to drive the hook block 10 in the state where the restriction of the hook hoisting movement by the overwinding prevention device 22 is released, and the hook block 10 is driven to wind up. It is supposed to be stored in. In this retracted state, the crane can be moved or parked.

  In order to return the hook block 10 in the hook retracted state to the crane working position, the normal winch control valve 18 is switched and the hook block 10 is driven to be lowered so as to be below the overwinding position U (release the overwinding state). Boom drive is enabled), and then the hoisting control valve 17 and the telescopic control valve 16 are switched so that the telescopic boom 7 is lifted and extended to return to the working posture (shown by the one-dot chain line in FIG. 2). It has become. However, as shown in FIG. 3, when there is a load B on the loading platform 3 of the truck 1 and the hook block 10 cannot be lowered below the overwinding position U due to interference with the load B, the telescopic boom 7 Since the raising and lowering movement is regulated by the overwinding prevention device 22, there is a problem that the telescopic boom 7 cannot be raised and cannot be returned to the working posture.

Therefore, when the hook storage release switch is provided in the controller and the hook block 10 cannot interfere with the load B on the loading platform 3 and return to the working position, the hook storage release switch is operated to raise and lower the undulation control valve. The winch control valve is switched to the lowering side, and the hook retracting device can release the hook retracted state without interfering with the loading platform B by simultaneously driving the raising and lowering of the telescopic boom and the lowering motion of the hook block. Has been proposed (see, for example, Patent Document 1).
JP 2003-182978 A

  However, the hook storage release device described in Patent Document 1 simultaneously drives the raising and lowering of the telescopic boom and the lowering movement of the hook block by operating the hook storage release switch, and loads the loading platform at a position where the hook block interferes. Even if an object is loaded, the hook storage state can be released without interfering with the load on the loading platform, and the workability is greatly improved. However, in order to shift the crane from the hook retracted state to the working posture (the state indicated by the one-dot chain line in FIG. 2), it is necessary to further switch the expansion / contraction control valve to the expansion side and extend the expansion / contraction boom. In general, when the telescopic boom is extended, the hook block rises with the extension movement and approaches an overwinding state, so that it is necessary to simultaneously drive the hook block to be lowered. For this reason, the operator presses the hook storage release switch to perform hook storage release control, and then switches between the expansion control valve and the winch control valve to simultaneously drive the boom extension movement and the hook lowering movement to shift to the working posture. There is a problem that the operation is complicated.

  The present invention has been made in view of the above problems, and is a crane improved in workability by automatically performing return control to a working posture including extension movement of a telescopic boom by a simple operation. An object of the present invention is to provide a storage release control device.

  The present invention has the following configuration as means for solving the above problems.

  That is, the crane storage release control device of the present invention is a swing post that is pivotably mounted on a base, and is pivotally supported on the upper portion of the swing post so that it can be wound up and down via a wire rope from the tip. Telescopic boom with hanging hook block, hoisting cylinder driven by control oil from hoisting control valve, hoisting cylinder driving telescopic boom, telescopic cylinder driven by control oil from telescopic control valve, telescopic boom driving telescopic boom, winch control valve Equipped with a winch device that is driven by control oil from and drives the wire rope to wind up and down, and a controller that outputs a valve switching signal for switching the control valves, and retracts the telescopic boom in the crane retracted state.・ For cranes configured to store the hook block in the hook storage position along the bottom surface of the tip of the telescopic boom That.

  The storage release control device of the present invention comprises a storage release instruction switch for instructing storage release control for returning the crane from the storage state to the working position, and an extension operation means for instructing extension driving of the telescopic boom. Outputs a valve switching signal for switching the hoisting control valve to the raising side and the winch control valve to the lowering side based on the storage release instruction signal from the storage release instruction switch to raise and lower the telescopic boom and hook block. Simultaneously, the valve switching signal to switch the expansion / contraction control valve to the expansion side is output after the valve switching signal to the undulation control valve is cut off based on the operation signal from the expansion operation means. The boom extension movement and the hook block lowering movement are driven simultaneously.

  According to the storage release control device configured as described above, in order to return to the working posture in order to start work from the crane storage state, if the operator operates the storage release instruction switch to indicate the start of the storage release control. Good. Upon receiving this operation signal, the controller outputs a valve switching signal for switching the hoisting control valve to the raising side and a valve switching signal for switching the winch control valve to the lowering side to raise and lower the telescopic boom. The hook block lowering movement is simultaneously driven. As a result, the hook block is lowered while the telescopic boom is raised, and the hook block can be returned to the suspended state without interfering with the load on the loading platform (the state shown in FIG. 1 in a chain line). The control speed of the boom raising and lowering movement in this control may be adjusted to a speed at which the hook block descends during the control and does not interfere with the load on the loading platform.

  And if a hook block will be in a hanging state, an operator should just operate the expansion | extension operation means and instruct | indicate the expansion | extension drive of a telescopic boom. Upon receiving this operation signal, the controller cuts off the valve switching signal being output to the hoisting control valve, stops the raising / lowering drive of the telescopic boom, and instead outputs a valve switching signal for switching the telescopic control valve to the expansion side. Thus, the extension movement of the telescopic boom and the hook block lowering movement are driven simultaneously. As a result, the telescopic boom extends while the hook block is being lowered while the boom raising and lowering motion is stopped, and the working posture as shown in FIG. During this control, the hook block will change the speed of the telescopic boom (the telescopic speed will increase significantly when the telescopic boom's telescopic system is switched from linear cylinder movement to wire simultaneous expansion / contraction), fluctuations in the control oil amount, etc. As a result, the hook block may rise and approach an overwound state. In this case, for example, when the hook block is wound up to the overwinding position U, the extension boom is temporarily stopped to drive only the hook block lowering movement, and then the extension control valve and the winch control valve are switched. The ratio (interlocking ratio) may be adjusted so that the hook lowering movement becomes relatively large, and the boom extension movement and the hook lowering movement may be simultaneously driven again.

  If the hook block is in a suspended state and the telescopic boom is lifted and extended by an arbitrary amount by these series of controls, the operation of the storage release instruction switch may be stopped to end the control. In response to the disappearance of the operation signal, the controller cuts off the valve switching signal being output to each control valve, stops driving, and ends the series of storage release control.

  In the storage release control device of the present invention, if the storage release instruction switch is operated, the boom raising motion and the hook lowering motion are performed in conjunction with each other to release the hook storage state, and the extension operation means can be additionally operated during the control. Since the boom extension movement and the hook lowering movement are performed in conjunction with each other and can be easily returned to the working position, the crane storage release control, which has been complicated in the past, can be performed with a simple operation, and the workability is greatly improved. It is. In addition, since the control can be switched to the boom extension movement at the operator's discretion, it can be switched after confirming the safety of the surroundings, thereby enabling safe control.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to FIG.

  A is a vehicle-mounted crane mounted on a chassis frame 1 a located between the cab 2 and the loading platform 3 of the truck 1. The vehicle-mounted crane A includes a crane base 5 having outrigger devices 4, 4 that can be installed to extend left and right, and a swing post 6 that is pivotably mounted on the crane base 5 by swing drive means 13. The telescopic boom 7 is pivotally supported by the hoisting cylinder 11 on the upper part of the swivel post 6 and the distal booms 7-2, 7-3,. A winch device attached to the telescoping cylinder 12, the swivel post 6, or the base end boom 7-1, which is housed in the telescopic boom 7 and sequentially drives the front end boom 7-2, 7-3. 8, a cargo handling hook block 10 suspended from a telescopic boom distal end portion 7a by a wire rope 9 drawn out from 8 so as to be freely wound up and down.

  23, when the work is finished and the crane is moved and moved, the hook block 10 suspended from the boom tip 7a is not swung due to vibration during running and the like so that the boom tip 7a and the like are not damaged. Is a hook storage device for storing the hook in the hook storage position along the lower surface of the telescopic boom tip 7a. In the case of this embodiment, the hook storage device 23 swings around the boom tip 7a when the hook block 10 is driven to wind up with the restriction of the hook winding movement by the overwinding prevention device 22 being released. Engage with the lower end of the hook storage link 23a that is pivotally supported, and swing further in the boom proximal direction together with the link 23a by further hoisting movement, and the hook storage position along the bottom surface of the boom tip (shown in the solid line in FIG. 1) ) Is stored. As another embodiment, the hook block 10 engages with an inclined cam (not shown) attached to the boom tip 7a, and is guided to the cam surface by further hoisting motion and swings in the boom proximal direction. Then, it can be configured to be stored in the hook storage position along the bottom surface of the boom tip.

  Reference numeral 14 denotes a swing control valve constituted by an electromagnetic switching type three-position switching valve, which supplies and discharges the hydraulic oil discharged from the hydraulic pump 15 to the swing drive means 13 by the switching operation to the right or left turning position. The telescopic boom 7 is driven to turn. Similarly, 16 is an expansion / contraction control valve composed of an electromagnetic switching type three-position switching valve, which supplies and discharges the hydraulic oil to and from the expansion / contraction cylinder 12 by the switching operation to the expansion or contraction position to extend / contract the expansion / contraction boom 7. It is like that. Similarly, 17 is a hoisting control valve composed of an electromagnetic switching type three-position switching valve. The hoisting cylinder 7 is driven by hoisting by supplying and discharging pressure oil to the hoisting cylinder 11 by switching to the raising or lowering position. It is supposed to be. 18 is a winch control valve similarly constituted by a three-position switching valve of electromagnetic switching type, and pressure oil is supplied to and discharged from the winch device 8 by switching operation to a hoisting or lowering position, and the hook block 10 is hoisted and wound. It is designed to drive down.

  Reference numeral 24 denotes a wired or wireless remote control means. The operation panel 24a has a turning operation means 25 for switching the turning control valve 14 to the right or left turning position, and an expansion / contraction control valve 16 is extended or reduced. Telescopic operation means 26 for switching to the position, hoisting operation means 27 for switching the hoisting control valve 17 to the raising or lowering position, winch for switching the winch control valve 18 to the hoisting or lowering position An operating means 28 is provided. Reference numeral 29 denotes a storage release instruction switch for instructing storage release control for returning the crane in the storage state to a working position by a push operation, and 30 is a power switch for on / off control of the power supply of the crane. In this embodiment, the storage release instruction switch 29 is configured by a pushbutton switch that outputs a storage release instruction signal only during a push operation, but is held after the storage release instruction signal is output by the push operation, A momentary switch that is released by pressing again may be used.

  Reference numeral 31 denotes a controller that receives the operation signal transmitted from the remote operation means 24, and switches the control valves 14, 16, 17, and 18 based on the operation signal received by the reception means 31a. Operation signal output means 31b for outputting a valve switching signal for the purpose. The operation signal output means 31b receives a turning operation signal from the remote operation means 24, and outputs a valve switching signal for switching the turning control valve 14 in the corresponding direction. In response to the signal, the expansion / contraction operation signal output unit 31b2 outputs a valve switching signal for switching the expansion / contraction control valve 16 in the corresponding direction. Similarly, in response to the undulation operation signal, the undulation control valve 17 is switched in the corresponding direction. The hoisting operation signal output unit 31b3 that outputs the valve switching signal of the winch, the winch operation signal output unit 31b4 that outputs the valve switching signal for switching the winch control valve 18 in the corresponding direction in response to the winch operation signal, and the storage The release operation signal output unit 32 is configured.

  The storage release operation signal output unit 32 of the controller 31 includes an operation signal (storage release instruction signal) of the storage release instruction switch 29 transmitted from the remote operation means 24 and an operation signal (extension operation signal) to the expansion side of the expansion / contraction operation means 26. ), The following valve switching signal is output to the undulation control valve 17, the expansion / contraction control valve 16, and the winch control valve 18 to perform the storage release control. That is, the storage release operation signal output unit 32 first sets the undulation control valve 17 to the rising side based on the operation signal of the storage release instruction switch 29 (the storage release instruction signal transmitted from the remote operation means 24 wirelessly or by wire). A valve switching signal for switching the winch control valve 18 to the lowering side is output to switch both control valves 17 and 18 so that the raising and lowering movements of the telescopic boom 7 and the hook block 10 are driven simultaneously. It has become. As a result, the hook block 10 is lowered while the telescopic boom 7 is raised, and the hook block 10 can be returned to the suspended state as shown in FIG. is there. In this control, if the hook block 10 is wound down until it is in a suspended state, the raising / lowering state of the telescopic boom 7 is arbitrary, and the operator may control the rising state as necessary.

  Next, when the telescopic boom 7 is in an arbitrary raising state and the operator operates the telescopic operation means 26 of the remote operation means 24 to the expansion side, the storage operation signal output unit 31 receives the operation signal on the expansion side (remote operation Based on the expansion operation signal transmitted from the means 24 wirelessly or by wire), the valve switching signal being output to the hoisting control valve 17 is cut off to stop the raising / lowering drive of the telescopic boom 7, and the telescopic control valve 16 is extended instead. The control valve 16 is switched by outputting a valve switching signal for switching to the side to drive the extension movement of the telescopic boom 7 and the lowering movement of the hook block 10 simultaneously. As a result, the hook block 10 is unwound while the telescopic boom 7 is extended in a state in which the boom raising and lowering motion is stopped, and the working posture is as shown in FIG. During this control, the hook block 10 may rise due to a change in the speed of the telescopic boom 7 and approach an overwinding state. In this case, the overwinding prevention device 22 is activated to temporarily extend the telescopic boom 7. Stop and drive only the lowering movement of the hook block 10, and then adjust the switching ratio of the expansion / contraction control valve 16 and winch control valve 18 so that the hook lowering movement becomes relatively large, and the boom extension movement and the hook winding again. What is necessary is just to comprise so that a downward motion may be driven simultaneously. Even in this control, when the hook block 10 is in an overwound state, the interlock ratio may be adjusted again by adjusting the switching ratio. Note that this overwinding state avoidance control can be omitted depending on the individual operation of the operator.

  Then, when the crane retracted state is released through the series of controls and the working posture is reached, the operation of the storage canceling instruction switch 29 may be stopped. Since the storage operation signal output unit 32 receives the disappearance of the storage release command signal, it stops the drive by cutting off the valve switching signal being output to the expansion / contraction control valve 16 and the winch control valve 18, and ends the series of storage release control. is there.

  Further, the remote control means 24 is provided with speed command means 33 for increasing / decreasing the crane drive speed in the grip portion 24b, and the speed command means 33 is set to the speed increasing side during a series of storage release control. When operated, the storage operation signal output unit 32 performs speed-up control of the valve switching signal output to each control valve 16, 17, 18 based on this speed command signal, and performs storage release control at high speed. For this reason, the storage release control can be promptly terminated.

  Further, if the turning operation means 25 is operated to the right or left turning side during the storage release control, in addition to the normal storage release control, the turning control valve 14 is switched from the turning operation signal output unit 31b1 to the right or left turning position. A valve switching signal is output, and the turning drive of the telescopic boom 7 can be controlled simultaneously. Thus, when the turning control of the telescopic boom 7 is controlled together during the storage release control, it is possible to quickly shift to the working posture.

  Next, the operation of this embodiment will be described.

  In order to return the crane to the working position, the truck 1 is first stopped at the work site and the outrigger devices 4 and 4 are installed. Next, the storage release instruction switch 29 of the remote operation means 24 may be pushed to instruct the start of storage release control. The storage release operation signal output unit 32 receives the storage release instruction signal and outputs a valve switching signal for switching the hoisting control valve 17 to the raising side and the winch control valve 18 to the lowering side. Drive the lifting and lowering movement of the hook block 10 simultaneously. As a result, the hook block 10 is lowered while the telescopic boom 7 is raised, and the hook block 10 can be suspended without interfering with the load B on the loading platform 3.

  Next, when the telescopic boom 7 is raised to an arbitrary raising state, the operator may operate the telescopic operation means 26 of the remote operation means 24 to the extension side. The storage operation signal output unit 32 receives this expansion operation signal, cuts off the valve switching signal being output to the hoisting control valve 17 and stops the raising / lowering drive of the telescopic boom 7, and instead moves the telescopic control valve 16 to the expansion side. A valve switching signal for switching is output, and the extension movement of the telescopic boom 7 and the lowering movement of the hook block 10 are simultaneously driven. As a result, the hook block 10 is unwound while the telescopic boom 7 is extended in a state where the boom raising and lowering motion is stopped, and the working posture as shown by the one-dot chain line in FIG. 1 can be returned.

  When the crane is in the working posture, the operation of the storage release instruction switch 29 is stopped and the storage release control is stopped. Thereafter, the control valves 14, 16, 17, 18 may be switched to perform normal crane work. Further, when it is desired to end the storage release control promptly, the speed command means 33 may be operated to the speed increasing side. If the speed command means 33 is operated to the acceleration side, the valve switching signal output from the storage operation signal output unit 32 to each control valve 16, 17, 18 is subjected to acceleration control, and storage release control is performed at high speed. is there.

  In addition, if the turning operation means 25 is operated to the right or left turning side during the storage release control, a valve switching signal is output from the turning operation signal output unit 31b1 to the turning control valve 14 simultaneously with the storage release control, and the storage release control is in progress. At the same time, the boom turning drive is driven, and it is possible to promptly shift to the working posture.

It is explanatory drawing explaining the structure of the storage cancellation | release control apparatus of the crane in this invention. It is explanatory drawing explaining the structure of a vehicle mounting type crane. It is explanatory drawing of hook storage cancellation | release control.

Explanation of symbols

A vehicle-mounted crane,
B Load,
1 track,
1a chassis frame,
2 cab,
3 cargo bed,
4 Outrigger device,
5 Crane base,
6 swivel post,
7 telescopic boom,
8 winch device,
9 Wire rope,
10 hook block,
11 Rolling cylinder,
12 telescopic cylinder,
13 swivel drive,
14 swivel control valve,
15 hydraulic pump,
16 telescopic control valve,
17 Undulating control valve,
18 winch control valve,
19 Main relief valve,
21 Solenoid valve for unloading,
22 Overwinding prevention device,
23 hook storage device,
24 remote control means,
25 swivel operation means,
26 Telescopic operation means,
27 Relief operation means,
28 Winch operating means,
29 Command switch for releasing storage,
30 power switch,
31 controller,
31a receiving means,
31b Operation signal output means,
31b1 Turn operation signal output section,
31d2 Telescopic operation signal output section,
31b3 Undulating operation signal output section,
31b4 winch operation signal output section,
32 Store release operation signal output section,

Claims (1)

From a swivel post that is pivotably mounted on a base, a telescopic boom that is pivotally supported on the upper part of the swivel post and that is suspended from the tip via a wire rope and suspended from a hook block, and a hoisting control valve The hoisting cylinder driven by the control oil of the hoisting mechanism, the hoisting cylinder for hoisting the telescopic boom, the telescopic cylinder driven by the control oil from the telescopic control valve, and the telescopic boom driven by the control oil. A winch device for driving down, and a controller for outputting a valve switching signal for switching each of these control valves, and retracting the telescopic boom to the lowest level when the crane is retracted, and lowering the hook block to the lower surface of the distal end of the telescopic boom In the storage release control device of the crane that stores in the hook storage position along
A storage release instruction switch for instructing a storage release control for returning the crane from the storage state to the working position; and an extension operation means for instructing an extension drive of the telescopic boom. Based on the release instruction signal, a valve switching signal for switching the hoisting control valve to the raising side and the winch control valve to the lowering side is output to simultaneously drive the raising and lowering movement of the telescopic boom and the lowering movement of the hook block. The extension boom is extended and hooked by outputting a valve switching signal for switching the extension control valve to the extension side after cutting off the valve switching signal to the undulation control valve based on the extension operation signal from the extension operation means. A crane retract release control device characterized in that the block lowering motion is driven simultaneously.

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