JP2004203595A - Hook operating device of crane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To securely interlock operation of rise of a boom from a hook storage condition and operation of hook storage release when starting work. <P>SOLUTION: This crane is provided with the boom rising and falling down, a winch for winding up and down a hook, an excessive winding prevention device, and a hook storage device. A change-over control valve 20 for raising and putting down the boom for controlling a hydraulic cylinder 9 for raising and putting down the boom and a change-over control valve 50 for winch for controlling a hydraulic motor 10 for winch are provided with proportional electromagnetic change-over valves 24, 25, 54, 55 for switching main spools 21, 51 and displacement detectors 23, 53 for detecting displacement amount of the main spools 21, 51, respectively. A computing device 40 is provided to obtain required displacement amount of the main spools 21, 51 by corresponding to an operation signal for changing from a running attitude at which the hook is stored to work attitude and send a control signal for interlocking operation of rise of the boom and operation of hook storage release to the proportional electromagnetic change-over valves 24, 25, 54, 55 only when the obtained displacement amount is in a stable operation region. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane hook operating device capable of interlocking the operation of standing up a boom and releasing a hook from storage.
[0002]
[Prior art]
In a vehicle-mounted crane, a base is fixed on a chassis frame between a truck bed and a driver's cab, and a column is provided on the base so as to be freely rotatable. Supported. The column is provided with a winch, from which the wire rope is guided to the tip of the boom, and the hook is suspended from the tip of the boom by hanging it on a hook via a pulley at the tip of the boom. ing.
[0003]
In this crane, when the hanging length of the hook is a predetermined length or less, a so-called winding state, the crane stops operating in the winding direction where the tip of the boom and the hook approach each other, and the boom and the hook collide. It is equipped with a winding prevention device for preventing
In addition, a hook storage device is provided for storing the hook in contact with the tip of the boom in a running state of the truck to prevent the hook from swinging during running. In this hook storage device, a winding operation for storing the hook can be performed regardless of whether the hook is in a winding state.
[0004]
As described above, in the crane having the winding-over prevention device and the hook storage device, when the boom is horizontal and the running posture in which the hooks are stored is changed to the working posture, the hooks are stored and in a winding state. However, the boom cannot be raised in this state. This is because the raising operation of the boom is performed in the winding direction in which the hook approaches the tip of the boom.
[0005]
Therefore, in such a case, the boom must be erected after the hook is once lowered to release the winding state.
However, when a load is loaded on the truck bed, the hook cannot hit the load and can be lowered, so once rotate the boom to position the hook outside the load bed, then lower the hook and roll The boom had to be erected after the transient was released. Therefore, the operation from the running posture to the time when the crane operation can be performed is troublesome.
[0006]
Therefore, a crane hook operating device has been proposed in which the operation of raising the boom and releasing the hook can be linked by simply operating one switching valve at the start of the work so that the crane operation can be easily started from the running posture ( Patent Document 1).
The hook operating device of this crane includes a hook storage switching valve and a storage up-and-down interlocking switching valve. When the traveling posture in which the hooks are stored is changed to the working posture, the operation of releasing the storage of the hook storage switching valve is performed. I do.
[0007]
When the hook storage switching valve is operated to the storage release side, the storage up / down interlocking switching valve is also switched to the storage release side, and as the hook is lowered, the boom raising / lowering cylinder extends and the boom rises. It is not necessary to lower the hook once to release the winding state before raising the boom.
However, in the above crane hook operating device, at the start of the work, the operation of releasing the storage of the hook from the stored state of the hook and the operation of raising the boom can be linked by operating only one switching valve. There is a problem that hydraulic piping is required.
[0008]
Therefore, there has been proposed a crane hook operating device that does not require complicated hydraulic piping, and can interlock the release of the hook and the operation of raising the boom from the stored state of the hook at the start of work.
The hook operating device of this crane was provided with a boom for raising and lowering operation by a hydraulic cylinder for boom raising and lowering, a winch for raising and lowering the hook by a hydraulic motor for winch, a winding prevention device, and a hook storage device. In a crane, a switching means for switching a main spool and a displacement for detecting a displacement amount of a main spool are provided to a switching control valve for lifting a boom and a switching control valve for operating a winch hydraulic motor for operating a hydraulic cylinder for raising and lowering a boom. And a calculating device for determining a required control amount for interlocking the hook storage release and the boom standing operation based on the detection data of the displacement detecting means, and transmitting a control signal to the switching means. .
[0009]
The hook operating device of this crane switches the boom-up / down switching control valve to perform the upright operation when changing from the running posture in which the hooks are stored to the working posture at the start of the work. Then, the displacement amount of the main spool of the switching control valve for raising and lowering the boom is detected by the displacement detecting means, and a detection signal is sent to the arithmetic unit.
The arithmetic unit obtains the control amount of the winch switching control valve necessary for interlocking the hook storage release and the boom standing operation based on the detection data of the displacement detecting means. Send control signal.
[0010]
The winch switching control valve is controlled by this control signal, and the winch is lowered corresponding to the rise of the boom, so that the release of the hook storage and the operation of the rise of the boom are properly linked.
Therefore, there is no need to lower the hook once to release the winding state before raising the boom. Also, when a load is loaded on the loading platform, the hook will not hit the loading, so once rotate the boom to position the hook outside the loading platform, lower the hook and release the winding state Then, the trouble of erecting the boom is not required, and the crane operation can be started immediately (refer to the prior application: Japanese Patent Application No. 2001-150825).
[0011]
[Patent Document 1]
JP 2001-39684 A
[0012]
[Problems to be solved by the invention]
However, the displacement detecting means detects the displacement of the main spool of the boom-up / down switching control valve and the winch switching control valve, and, based on the detected data, interlocks the hook storage release and the boom upright operation. In the crane hook operating device, when operating at low speed, the opening area of the main spool is extremely small, so the temperature of the hydraulic oil and its viscosity change, the boom hoisting cylinder which is the main spool and the actuator, and the hydraulic motor for the winch Due to factors such as unstable frictional force, the flow rate of pressure oil supplied from the switching control valve to the actuator is not constant, and the operating speed of the boom erecting and hook lowering occurs. And the hook release operation may not work properly (hereinafter, the opening area of the main spool is extremely small Ku unstable zone actuating the displacement range of the main spool actuation of upstanding hook store release does not properly interlock the boom, that operates stably zone a displacement zone of the main spool to properly interlocked).
[0013]
The present invention solves the above-mentioned problem in a hook operating device of a crane, and it is possible to reliably interlock the operation of raising the boom and releasing the hook storage from the hook storage state at the start of work, and the crane that is easy to operate It is an object of the present invention to provide a hook operating device.
[0014]
[Means for Solving the Problems]
A hook operating device for a crane according to the present invention includes a boom that raises and lowers an operation by a hydraulic cylinder for raising and lowering a boom, a winch that raises and lowers a hook by a hydraulic motor for a winch, a winding prevention device, and a hook storage device. In a crane equipped with a boom hoisting hydraulic control cylinder for controlling a boom hoisting hydraulic cylinder and a winch switching control valve for controlling a winch hydraulic motor, a switching means for switching the main spool and a displacement amount of the main spool are detected. And a required displacement amount of the main spool is obtained in accordance with an operation signal for changing the running posture in which the hook is stored to the working posture, and the obtained displacement amount is in the operation stable range. Only when the operation is performed, a control signal for interlocking the operation of raising the boom and releasing the hook storage is transmitted to the switching means. By providing the location, and the above-mentioned problems are eliminated.
[0015]
The hook operating device for a crane according to the present invention sends an operation signal from the operating means to the arithmetic unit when the working posture is changed from the running posture in which the hook is stored at the start of the work. The arithmetic unit determines a required displacement amount of the main spool in response to an operation signal for changing the running posture to the working posture, determines whether the obtained displacement amount is in the operation stable region, and determines whether the obtained displacement amount is in the operation stable region. At this time, a control signal is transmitted to the switching means for interlocking the operation of the boom standing and the hook storage release operation.
[0016]
The control signal controls the switching control valve for raising and lowering the boom and the switching control valve for winch, and the winch is lowered in response to the rising of the boom, so that the operation of the boom rising and the release of the hook storage are appropriately linked. .
When the amount of displacement of the main spool determined from the operation signal is extremely small and is in an unstable operation range, the arithmetic unit does not send a control signal to the switching means for interlocking the operation of the boom standing and the hook storage release. Therefore, unstable operation is not performed.
[0017]
Therefore, the operation of raising the boom and releasing the hook storage from the hook storage state at the start of the work can be reliably linked.
Providing manual interlocking operation means for outputting an operation signal for changing from the running posture in which the hook is stored to the working posture during manual operation, the interlocking operation of boom standing up and hook storage cancellation during manual operation can be easily performed. .
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a front view of a crane provided with a hook operating device according to an embodiment of the present invention, FIG. 2 is a configuration diagram of the hook operating device of the crane, and FIG. 4 is a side view of the crane showing a state mounted on the vehicle, FIG. 5 is an explanatory view of the operation of the crane, FIG. 6 is a front view of the remote controller, FIG. 7 is a side view of the remote controller, and FIG. FIG. 9 is a diagram showing a function formula for raising a hydraulic cylinder, FIG. 9 is a diagram showing a function formula for spool displacement for winch lowering and winch lowering, FIG. 10 is a diagram showing a function formula for raising a hydraulic cylinder for raising / lowering a boom, and FIG. FIG. 12 is a diagram showing a spool displacement amount function formula for boom erecting and winch lowering, and FIG. 12 is a flowchart showing an example of the operation of the hook operating device of the crane.
[0019]
In the crane 1, a column 6 is rotatably provided on a base 4 provided with an outrigger 2, and a boom 7 that expands and contracts is pivotally supported on the upper end of the column 6 so as to be able to move up and down. The column 6 is provided with a winch 11. From the winch 11, a wire rope 12 is guided to the tip of the boom 7, and is connected to a hook 13 for hanging loads via a pulley (not shown) at the tip of the boom 7. The hook 13 is suspended from the tip of the boom 7 by being hung.
[0020]
The crane 1 pivots the column 6, raises and lowers and expands and lowers the boom 7, and operates the winch 11 to lower and raise the winch 11. A winch hydraulic motor 10 is provided.
The crane 1 is mounted on a chassis frame 16 of the vehicle 15, and the hydraulic motor for turning 5, the hydraulic cylinder 9 for raising and lowering the boom, the hydraulic cylinder 8 for extending and retracting the boom, and the hydraulic motor 10 for winch are all powered by the engine of the vehicle 15. It operates by supplying pressure oil from a driven hydraulic pump (not shown) via the switching control valve device 3.
[0021]
The switching control valve device 3 is a turning switching control valve (not shown) for controlling respective actuators of a hydraulic motor 5 for turning, a hydraulic cylinder 9 for raising and lowering a boom, a hydraulic cylinder 8 for extending and retracting a boom, and a hydraulic motor 10 for a winch. ), A boom-up / down switching control valve 20, a boom expansion / contraction switching control valve (not shown), and a winch switching control valve 50. Remote operation by the operation device 70 is possible.
[0022]
The boom-up / down switching control valve 20 and the winch switching control valve 50 have built-in main spools 21 and 51, and the main spools 21 and 51 are normally held at neutral positions by springs 30 and 60. . One ends of the main spools 21 and 51 are connected to the operation lever 14 via links. Pilot pistons 22 and 52 are formed at the other end, and iron cores 27 and 57 are provided at the distal ends of the piston rods 26 and 56. The iron cores 27 and 57 are inserted into position detectors 23 and 53 having a hollow cylindrical differential transformer.
[0023]
The position detectors 23 and 53 are displacement detecting means for detecting the amount of displacement of the main spools 21 and 51. When the main spools 21 and 51 are displaced, the iron cores 27 and 57 move, and the position detectors 23 and 53 move. Since the induced electromotive force is generated in the differential transformer 53, the displacement amount of the main spools 21 and 51 can be detected. The detection signal is sent to the arithmetic unit 40 via the analog / digital converters 29 and 59.
[0024]
Proportional electromagnetic pilot valves 24, 25, 54 and 55 for controlling the main spools 21 and 51 are provided outside the boom-relief switching control valve 20 and the winch switching control valve 50, respectively. A control signal is sent from the arithmetic unit 40 to the solenoids 24S, 25S, 54S, and 55S via the amplifiers 24A, 25A, 54A, and 55A.
[0025]
The proportional electromagnetic pilot valves 24, 25, 54 and 55 have a port P to which pilot pressure oil is supplied from a hydraulic pump, a port P is always closed, and a port T for returning hydraulic oil to a tank is always open, and the solenoids 24S, 25S , 54S, 55S, the pilot spools 24R, 25R, 54R, 55R slide, and the opening amount of the P port can be controlled by the input current value. Accordingly, the supply of the pilot pressure oil to the left and right oil chambers 31, 32, 61, 62 of the pilot pistons 22, 52 is controlled.
[0026]
When the pilot pressure oil is supplied to one of the left and right oil chambers 31, 61 or 32, 62, the main spools 21, 51 move left or right, and the service ports A, B and the pump port P The boom-up / down switching control valve 20 and the winch switching control valve 50 operate the boom-up / down hydraulic cylinder 9 and the winch hydraulic motor 10.
[0027]
For example, as shown in FIG. 3, when the main spool 21 of the boom-up / down switching control valve 20 moves to the right to connect the service port B with the pump port P, the boom-up / down hydraulic cylinder 9 is extended and the boom 7 is extended. Erect.
When the main spool 51 of the winch switching control valve 50 moves to the right and the service port B communicates with the pump port P, the winch hydraulic motor 10 rotates downward and the winch 11 winds the hook 13. Perform lowering.
[0028]
When the main spools 21 and 51 are displaced, the iron cores 27 and 57 move, and the displacement of the main spools 21 and 51 is detected as a voltage value by the differential transformer of the position detectors 23 and 53. The obtained voltage values are converted into digital signals by the analog / digital converters 29 and 59 and fed back to the arithmetic unit 40.
The arithmetic unit 40 compares the value fed back with the output value of the control signal and corrects any excess or deficiency, so that the switching control valves 20 and 50 can accurately control the opening amount. If the feedback value is abnormal, a crane stop signal is output to the unload valve 44.
[0029]
When the crane 1 is remotely controlled, the switching control valve device 3 is switched by the remote controller 70.
As shown in FIGS. 6 and 7, the remote controller 70 includes a boom hoisting tact switch 71 for selecting the hoisting operation of the boom 7 and a winch winding up / down tact switch for selecting the hoisting and lowering operation of the winch 11. 72, a boom extension / retraction tact switch 73 for selecting the extension / retraction operation of the boom 7, a rotation tact switch 74 for selecting the left / right pivoting operation of the boom 7, a slow mode switch 75, and the speed of each operation of the crane are controlled. A speed lever 76 is provided.
[0030]
When the required hydraulic actuator is selected by the tact switches 71, 72, 73, 74 of the remote controller 70 and the speed lever 76 is pulled, the selection signal of the hydraulic actuator and the signal of the speed lever are changed to the remote controller 70 as operation signals. Is transmitted wirelessly to the switching control valve device 3. This operation signal is sent to the arithmetic unit 40 via the receiver 41.
[0031]
The arithmetic unit 40 stores necessary control data, calculates the displacement of the main spools 21 and 51 based on the selection signal and the displacement signal, and sends the pilot amount to the proportional electromagnetic pilot valves 24, 25, 54 and 55. Send control signal.
The crane 1 includes a well-known winding prevention device and a hook storage device (not shown). In a running posture, as shown in FIG. . In this state, the winding switch 42 of the winding prevention device is operating (on).
[0032]
When the work posture is changed from the traveling posture to the work posture at the start of the work, if the luggage W is loaded on the bed 17 of the vehicle 15, it is necessary to interlock the rising operation of the boom 7 and the retracting operation of the hook 13 as shown in FIG. is there.
In the hook operating device of this crane, when the operation signal of the boom erection is received from the remote controller 70 with the winding switch 42 being on, the arithmetic unit 40 calculates the boom erection hydraulic cylinder erecting function formula shown in FIG. The amount of indexing and the amount of pull-off are substituted into this function expression to determine the amount of displacement of the boom raising / lowering spool standing side.
[0033]
Further, the obtained displacement amount of the boom raising / lowering spool standing side is substituted into the boom raising / winch lowering spool displacement amount function formula shown in FIG. 9, and the winch spool lowering side with respect to the boom raising / lowering spool rising side displacement amount. The amount of displacement is determined, and a pilot control signal is sent to the proportional electromagnetic pilot valves 24, 25, 54, 55. At the same time, an accelerator opening control signal is sent to the engine.
[0034]
As a result, the operation of boom standing and hook storage release are linked.
When the speed lever 76 is operated only slightly and the pull-off amount is extremely small, and is substituted into the function formula for raising the hydraulic cylinder for raising and lowering the boom in FIG. If it is within the range, the arithmetic unit 40 does not calculate the winch spool lowering side displacement amount, and does not send out pilot control signals to the proportional electromagnetic pilot valves 24, 25, 54, 55.
[0035]
When the displacement amount of the speed lever 76 increases and the displacement amount of the boom raising / lowering spool standing side reaches the operation stability region S, the arithmetic unit 40 calculates the winch spool lowering side displacement amount, and the proportional electromagnetic pilot valve 24, Send pilot control signals to 25,54,55.
When operating at a low speed, the low speed mode switch 75 of the remote controller 70 is turned on to set the low speed mode.
[0036]
When the operation signal of the boom rising is received from the remote controller 70 in the state where the winding switch 42 is on and in the slow speed mode, the arithmetic unit 40 calculates the function formula for raising the hydraulic cylinder for raising and lowering the slow speed boom shown in FIG. The displacement amount is substituted into this function expression to determine the boom raising / lowering spool standing side displacement amount.
Further, the obtained displacement amount of the boom-raising main spool rising side is substituted into a slow speed boom rising / winch lowering spool displacement amount function formula shown in FIG. The amount of lower displacement is obtained, and a pilot control signal is sent to the proportional electromagnetic pilot valves 24, 25, 54, 55.
[0037]
As a result, the operation of boom standing and hook storage release are linked.
When the speed lever 76 is operated only slightly and the pull-off amount is extremely small, and when substituted into the function formula for raising the hydraulic cylinder for raising / lowering the boom of FIG. If it is within U, the arithmetic unit 40 does not calculate the winch spool lower displacement, and does not send out pilot control signals to the proportional electromagnetic pilot valves 24, 25, 54, 55.
[0038]
When the displacement amount of the speed lever 76 increases and the displacement amount of the boom raising / lowering spool standing side reaches the operation stability region S, the arithmetic unit 40 calculates the winch spool lowering side displacement amount, and the proportional electromagnetic pilot valve 24, Send pilot control signals to 25,54,55.
Therefore, the unstable operation in the unstable operation region is not performed, and the operation of raising the boom 7 and the operation of releasing the storage of the hook 13 from the hook storage state at the start of the work are reliably linked.
[0039]
When the crane 1 is manually operated, the operation lever 14 of the switching control valve device 3 is manually switched. However, at the start of the work, the operation of raising the boom 7 and releasing the storage of the hook 13 is performed by a switching control valve for boom raising and lowering. In order to interlock the operation lever 14 of the winch switching control valve 50 and the operation lever 14 simultaneously without manually operating the same, the hook operating device of this crane is provided with a boom-raising winch lowering interlock switch 43 as a manual interlocking operation means. I have.
[0040]
If there is no particular problem, the installation position of the boom-raising winch lowering interlocking switch 43 is preferably near the operation lever 14 as shown in FIG. The boom-raising winch lowering interlocking switch 43 can be used as appropriate, such as a toggle switch or a push button switch. However, a momentary switch that has a built-in spring and automatically returns to the original position is preferable because it is easy to click. This switch need only be released when it is desired to stop the operation.
[0041]
When the boom-raising winch lowering interlock switch 43 is turned on, an interlock operation signal is sent to the arithmetic unit 40. When the interlocking operation signal is received from the boom-raising winch lowering interlocking switch 43 while the winding switch 42 is on, the arithmetic unit 40 calculates a spool displacement amount function formula for boom raising and winch lowering shown in FIG.
A point corresponding to the number of clicks of the boom-raising winch lowering interlocking switch 43 is given to the boom-raising / winch lowering spool displacement amount function formula, and the arithmetic unit 40 sets the boom raising / lowering spool raising / lowering in accordance with the number of clicks. The side displacement amount and the corresponding winch spool lower displacement amount are obtained, and a pilot control signal is sent to the proportional electromagnetic pilot valves 24, 25, 54, and 55.
[0042]
Since the points corresponding to the number of clicks are all set within the operation stable area S, the operation of the boom standing and the hook retracting operation are reliably linked by pressing the boom standing winch lowering interlock switch 43.
When the operating speed is excessively increased, a separate deceleration switch (not shown) may be provided to reduce the operating speed. Clicking this deceleration switch can reduce the speed.
[0043]
The boom-raising winch lowering interlock switch 43 is easy to operate when installed near the operating lever 14. However, the operation of the boom raising winch lowering interlock switch 43 allows the main spool of the boom raising / lowering switching control valve 20 and the winch switching control valve 50. Since the members 21 and 51 are rapidly displaced, the operation lever 14 may move quickly and hit the operator.
[0044]
The spool displacement speed limiting function formula as shown in FIG. 13 is provided in the arithmetic unit 40, and the actual spool displacement speed obtained from the main spool displacement amount per operation time when the boom standing winch lowering interlock switch 43 is operated is the spool displacement speed. If the speed exceeds the speed limit by the limit function formula, the operation lever 14 can be operated slowly by reducing the spool displacement speed.
[0045]
To reduce the spool displacement speed, for example, reduce the amount of pilot pressure oil supplied to the operating proportional electromagnetic pilot valve, or send an operation signal to the opposite proportional electromagnetic pilot valve to It is advisable to take a method such as applying a brake to the operation.
Note that the boom standing-up winch lowering interlocking switch 43 is not provided, and the operation of the boom standing-up and the release of the hook storage can be linked by operating only one operation lever 14.
[0046]
In the crane 1, in the traveling posture, the hook 13 is stored, and the winding switch 42 of the winding prevention device is activated (on).
When the boom-raising winch lowering interlocking switch 43 is not provided, the operation lever 14 of the boom-raising / lowering switching control valve 20 is raised and the main spool 21 is displaced with the winding-over switch 42 being operated (on). By causing the arithmetic unit 40 to send a control signal to the proportional electromagnetic pilot valves 54 and 55 of the winch switching control valve 50 by a feedback signal from the position detector 23, the boom standing-up operation and the hook retracting operation can be linked. And
[0047]
In the state where the winding switch 42 is stopped (off), if the operation lever 14 of the switching control valve 20 for raising and lowering the boom is raised, only the boom is raised.
As shown in FIG. 14, a winch lowering interlock switch 45 may be provided instead of the boom standing winch lowering interlock switch 43.
In this case, when the winch lowering interlock switch 45 is turned on and the operating lever 14 of the boom raising / lowering switching control valve 20 is raised, an interlocking operation signal is sent to the arithmetic unit 40 so that the winch lowering operation is also interlocked, and the boom The main spool 21 of the up / down switching control valve 20 is displaced, and a feedback signal from the position detector 23 is sent to the arithmetic unit 40.
[0048]
The arithmetic unit 40 calculates the spool displacement function formula for boom erecting and winch lowering of FIG. 9 and substitutes the feedback displacement amount of the main spool 21 to calculate the required displacement amount of the main spool 51 of the winch switching control valve 50. Then, a control signal is sent to the lower proportional solenoid pilot valve 54. As a result, the operation of the boom standing and the hook storage release are linked.
[0049]
If the amount of operation of the operation lever 14 is small and the amount of displacement of the main spool 21 fed back is within the unstable operation range U in FIG. 15, the arithmetic unit 40 does not proceed to the next step and sends a crane stop signal to the unload valve 44. Output to prevent pressure oil from being supplied to the switching control valves 20 and 50.
Further, instead of the winch lowering interlocking switch 45, a boom upright interlocking switch (not shown) can be provided.
[0050]
In this case, when the operation lever 14 of the winch changeover control valve 50 is turned down by turning on the boom upset interlocking switch, an interlocking signal is sent to the arithmetic unit 40 so that the boom upset operation is also interlocked, and the winch changeover control is performed. The main spool 51 of the valve 50 is displaced, and a feedback signal from the position detector 53 is sent to the arithmetic unit 40.
[0051]
The arithmetic unit 40 calculates the spool displacement function formula for erecting the boom and lowering the winch shown in FIG. 9 and substitutes the feedback displacement amount of the main spool 51 for the required displacement amount of the main spool 21 of the switching control valve 20 for raising and lowering the boom. And sends a control signal to the standing-side proportional electromagnetic pilot valve 24. As a result, the hook storage release and the boom standing operation are linked.
[0052]
If the operation amount of the operation lever 14 is small and the feedback displacement amount of the main spool 51 is in the unstable operation range, the arithmetic unit 40 does not proceed to the next step and outputs a crane stop signal to the unload valve 44, Oil is not supplied to the switching control valves 20 and 50.
FIG. 16 is a diagram showing a function formula for raising a hydraulic cylinder for raising and lowering a boom and a function formula for lowering a hydraulic motor for a winch in another embodiment of the hook operating device. FIG. It is a figure which shows the functional formula for hydraulic motor lowering for a slow speed winch.
[0053]
In this case, the spool displacement amount function formula for raising the boom and lowering the winch as shown in FIG. 9 is not used, and the value of the displacement of the speed lever 76 is calculated by the function formula for raising the hydraulic cylinder for raising and lowering the boom and the function for lowering the hydraulic motor for the winch. The arithmetic unit 40 is configured to obtain control signals for the proportional electromagnetic pilot valves 24, 25, 54, 55 by substituting the respective values into the equations.
[0054]
That is, when the operation signal of the boom rising is received from the remote controller 70 while the winding switch 42 is in the on state, the arithmetic unit 40 performs the boom raising / lowering hydraulic cylinder rising function formula and the winch hydraulic motor lowering shown in FIG. And the displacement of the main spools 21 and 51 of the boom-up / down switching control valve 20 and the winch switching control valve 50 are obtained by substituting the displacement of the speed lever 76 into this function. A pilot control signal is sent to the electromagnetic pilot valves 24, 25, 54, 55. At the same time, an accelerator opening control signal is sent to an engine (not shown).
[0055]
As a result, the operation of boom standing and hook storage release are linked.
When the speed lever 76 is operated only slightly and the pull-off amount is extremely small, the main spool displacement obtained when substituting into the function formula for raising the hydraulic cylinder for raising and lowering the boom and the function formula for lowering the hydraulic motor for the winch in FIG. Is within the unstable operation range U, the arithmetic unit 40 does not send a pilot control signal to the proportional electromagnetic pilot valves 24, 25, 54, 55.
[0056]
When the displacement amount of the speed lever 76 increases and the displacement amount of the main spool reaches the operation stable region S, the arithmetic unit 40 sends a pilot control signal to the proportional electromagnetic pilot valves 24, 25, 54, 55.
When operating at a low speed, the low speed mode switch 75 of the remote controller 70 is turned on to set the low speed mode.
[0057]
When the operation signal of the boom erection is received from the remote controller 70 in the state where the winding switch 42 is on and in the low speed mode, the arithmetic unit 40 calculates the function expression for raising the hydraulic cylinder for raising and lowering the low speed boom shown in FIG. A hydraulic motor lowering function formula is determined, and the displacement amount is substituted into this function formula to determine the displacement amounts of the main spools 21 and 51 of the boom-up / down switching control valve 20 and the winch switching control valve 50, respectively. A pilot control signal is sent to the type pilot valves 24, 25, 54, 55.
[0058]
As a result, the operation of boom standing and hook storage release are linked.
When the speed lever 76 is slightly operated and the amount of pull-off is extremely small, the main spool obtained when substituting into the function formula for raising the hydraulic cylinder for raising / lowering the slow speed boom and the function formula for lowering the hydraulic motor for the slow speed winch in FIG. 17 is obtained. When the displacement is within the unstable operation range U, the arithmetic unit 40 does not send the pilot control signal to the proportional electromagnetic pilot valves 24, 25, 54, 55.
[0059]
When the displacement of the speed lever 76 increases and the displacement of the main spool reaches the operation stable region S, the arithmetic unit 40 sends a pilot control signal to the proportional electromagnetic pilot valves 24, 25, 54 and 55.
Therefore, the unstable operation in the unstable operation region is not performed, and the operation of raising the boom 7 and the operation of releasing the storage of the hook 13 from the hook storage state at the start of the work are reliably linked.
[0060]
When the crane 1 is manually operated, the boom upright winch lowering interlock switch 43 is turned on. When the boom-raising winch lowering interlock switch 43 is turned on, an interlock operation signal is sent to the arithmetic unit 40. When the interlocking operation signal is received from the boom erecting winch lowering interlocking switch 43 with the winding over switch 42 being on, the arithmetic unit 40 calculates the boom raising and lowering hydraulic cylinder erecting function equation and the winch hydraulic motor lowering function shown in FIG. Find out the expression.
[0061]
The function expression for raising the hydraulic cylinder for raising and lowering the boom and the function formula for lowering the hydraulic motor for the winch are each provided with a point corresponding to the number of clicks of the boom raising winch lowering interlocking switch 43. Then, the displacement amount of the boom raising and lowering spool and the displacement amount of the winch spool lowering side are calculated, and a pilot control signal is sent to the proportional electromagnetic pilot valves 24, 25, 54 and 55.
[0062]
Since the points corresponding to the number of clicks are all set within the operation stable area S, the operation of the boom standing and the hook retracting operation are reliably linked by pressing the boom standing winch lowering interlock switch 43.
When the operating speed is excessively increased, a separate deceleration switch (not shown) may be provided to reduce the operating speed. Clicking this deceleration switch can reduce the speed.
If you want to stop the operation, you only need to release the operation hand if it is a spring return type.
[0063]
【The invention's effect】
As described above, the hook operating device for a crane according to the present invention can reliably link the operation of raising the boom and releasing the hook storage from the hook storage state at the start of work with a simple operation.
[Brief description of the drawings]
FIG. 1 is a front view of a crane provided with a hook operating device according to an embodiment of the present invention.
FIG. 2 is a configuration diagram of a hook operating device of the crane.
FIG. 3 is an explanatory view of the operation of the hook operating device of the crane.
FIG. 4 is a side view of the crane showing a state where the crane is mounted on a vehicle.
FIG. 5 is an explanatory view of the operation of the crane.
FIG. 6 is a front view of the remote controller.
FIG. 7 is a side view of the remote controller.
FIG. 8 is a diagram illustrating a function formula for raising a hydraulic cylinder for raising and lowering a boom.
FIG. 9 is a diagram illustrating a spool displacement amount function formula for erecting a boom and lowering a winch.
FIG. 10 is a diagram showing a function formula for raising a hydraulic cylinder for raising and lowering a slow speed boom.
FIG. 11 is a view showing a spool displacement amount function formula for erecting a winch and lowering a winch;
FIG. 12 is a flowchart showing an example of the operation of the hook operating device of the crane.
FIG. 13 is a diagram showing a spool displacement speed limiting function formula.
FIG. 14 is a configuration diagram of a hook operating device of a crane provided with a winch lowering interlocking switch.
FIG. 15 is a diagram illustrating a relationship between an operation amount of an operation lever and a displacement amount of a spool.
FIG. 16 is a diagram showing a functional formula for raising a hydraulic cylinder for raising and lowering a boom and a functional formula for lowering a hydraulic motor for a winch.
FIG. 17 is a diagram showing a function formula for raising a hydraulic cylinder for raising and lowering a slow speed boom and a function formula for lowering a hydraulic motor for a slow speed winch.
[Explanation of symbols]
1 crane
3 Switching control valve device
4 Base
6 columns
7 Boom
9 Boom hoist hydraulic cylinder
10 Winch hydraulic motor
11 winches
12 wire rope
13 hooks
14 Operation lever
20 Boom hoist switching control valve
21 Main spool
23 Position detector
24 Proportional solenoid pilot valve
25 Proportional solenoid pilot valve
40 arithmetic unit
42 Winding switch
43 Boom standing winch lowering interlock switch
45 Winch lower link switch
50 Winch switching control valve
51 Main spool
53 Position detector
54 Proportional solenoid pilot valve
55 proportional solenoid pilot valve
70 Remote control
75 Fine speed mode switch
76 Speed lever

Claims (2)

In a crane provided with a boom that performs a raising and lowering operation by a hydraulic cylinder for boom raising and lowering, a winch that performs a hoisting and lowering operation of a hook by a hydraulic motor for a winch, a winding prevention device, and a hook storage device,
A switching control valve for controlling a hydraulic cylinder for raising and lowering a boom, a switching control valve for controlling a winch, a switching control valve for controlling a winch hydraulic motor, a switching means for switching a main spool thereof, and a displacement detecting means for detecting a displacement amount of the main spool. Together with each other,
A required displacement amount of the main spool is obtained in accordance with an operation signal for changing the running posture in which the hook is stored to the working posture, and only when the obtained displacement amount is in the operation stable region, the switching means causes the boom to stand up. A hook operating device for a crane, comprising an arithmetic unit for transmitting a control signal for interlocking the operation of releasing the hook storage. In a crane provided with a boom that performs a raising and lowering operation by a hydraulic cylinder for boom raising and lowering, a winch that performs a hoisting and lowering operation of a hook by a hydraulic motor for a winch, a winding prevention device, and a hook storage device,
A switching means for switching the main spool is provided in each of a boom-relief switching control valve for controlling the boom-lift hydraulic cylinder and a winch switching control valve for controlling the winch hydraulic motor,
Manual interlocking operation means for outputting an operation signal for changing the running posture in which the hook is stored to the working posture during manual operation, and a required displacement amount of the main spool in response to an operation signal from the manual interlocking operation means. A hook operating device for a crane, wherein the switching means is provided with an arithmetic unit for sending a control signal for interlocking the operation of boom standing and hook storage release.

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