JP3117791B2 - Crane hoisting stop control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane hoisting stop control device for stopping the boom hoisting drive without leaving the swing of a suspended load hung at the tip of the hoistable boom.

[0002]

2. Description of the Related Art A conventional crane of this type will be described below with reference to a mobile crane shown in FIG. As shown in FIG. 5, a conventional mobile crane has a telescopic boom 2 mounted on a vehicle 1 so as to be capable of turning and raising and lowering freely. Is suspended. The vehicle 1 is provided with outriggers 5a, 5b, 5c, and 5d that can protrude to the side of the vehicle 1 and contact the ground.
The telescopic boom 2 is pivotally attached to the vehicle 1 via a swivel 6 mounted on the vehicle 1 so that the telescopic boom 2 can be swiveled. The hydraulic cylinder 7 for raising and lowering is arranged between the telescopic boom 2 and the swivel table 6 at an appropriate position, and the hydraulic cylinder 7 for raising and lowering is driven so that the telescopic boom 2 can be raised and lowered. An operator cab 8 is arranged on the swivel 6. The hanging tool 3 is driven to be lifted and lowered by a wire rope 10 wound around a winch 9 arranged at the base end of the swivel base 6 or the telescopic boom 2. The swing drive of the swivel table 6 and the drive of raising and lowering the winch are performed by known drive means. During crane work, the outriggers 5a, 5b, 5c, and 5d are extended to touch the ground to stabilize the vehicle 1, and then the crane work is performed by extending and retracting the telescopic boom 2, raising and lowering, turning, and driving the winch. It is. Such mobile cranes are already known as truck cranes, rough terrain cranes, wheel cranes and the like.

A mobile crane of this type is provided with a safety device for ensuring safety during crane operation. This safety device is shown in FIG. 4 and described below.
In FIG. 4, A denotes a boom state detecting means for detecting the state of the telescopic boom 2 and is constituted by the following detecting means.
Reference numeral 11 denotes an undulation angle detecting means for detecting the undulation angle of the telescopic boom 2 and outputting an undulation angle signal of the telescopic boom 2. An angle meter composed of a weight and a potentiometer is attached to the telescopic boom 2, This is detection means for detecting the angle of elevation of the boom 2 by the angle to the ground. Numeral 12 is a length detecting means for detecting the length of expansion and contraction of the telescopic boom 2 and outputting a length signal of the telescopic boom 2, and a cord winder disposed between the distal end and the base end of the telescopic boom 2. And a potentiometer for detecting rotation of the cord winder. 13 is
A load detecting means for detecting a load acting on the telescopic boom 2, for example, a load cell provided on a rod of the hydraulic cylinder for raising and lowering the hydraulic cylinder 7 from the telescopic boom 2. Things.

[0004] Reference numeral 14 denotes a control unit, which is configured as follows. That is, the control unit 14 includes a limit value calculation unit 15 that calculates a limit value of a load that can be applied to the telescopic boom 2 based on signals from the undulation angle detection unit 11 and the length detection unit 12, Value and the load detecting means 1
3 is provided with a comparing means 16 which compares the detected actual value of the load with the detected actual value and outputs a work limit signal when the latter value reaches the former. Reference numeral 17 denotes a regulating unit which receives the work limit signal from the control unit 14 and regulates the related operation of the telescopic boom 2. In this case, the telescopic boom 2 moves up and down, expands and contracts, and the winch winds up. The operation on the dangerous side is restricted.

[0005] The control unit 14 includes an angle calculator 18 and a moment calculator 19. Angle calculator 18
Receives the signal from the undulation angle detecting means 11 to calculate the undulation angle of the telescopic boom 2, and receives the output signals from these to display the undulating angle of the telescopic boom 2 on the angle display 20. ing. The moment calculator 19 receives the signal from the load detecting means 13 and the limit value from the limit value calculating means 15, and the load acting on the telescopic boom 2 occupies the limit value obtained by the limit value calculating means 15. The ratios are calculated, and the output signals from these are displayed on the moment indicator 21 as the current moment value.

[0006] The safety device for a mobile crane constructed as described above operates as follows. That is, the state of the telescopic boom 2 during the crane operation is detected by the elevation angle detecting means 11 and the length detecting means 12, and the limit value calculating means 15 calculates the limit value of the load that can be applied to the telescopic boom 2. The comparing means 16 compares the limit value from the limit value calculating means 15 with the actual value of the load detected by the load detecting means 13, and when the latter value reaches the former, sends a work limit signal to the regulating means 17. Output. Then, telescopic boom 2
The operation on the dangerous side is avoided by restricting the undulating movement, the expansion and contraction movement, and the like. The operator operates while checking the state of the telescopic boom 2 sequentially with the angle display 20 and the moment display 21.

[0007]

However, in the crane provided with the above-described safety device for a mobile crane, when the actual value of the load reaches the limit value, a work limit signal is output from the comparison means 16 to the restriction means 17. Then, the operation on the dangerous side is stopped. However, if the operation is stopped suddenly, there is a problem that the suspended load suspended at the tip of the telescopic boom 2 is swung. Therefore, the operator operates the moment indicator 21 while constantly monitoring it. When the actual value of the load reaches the limit value, the operator performs an operation such as a fine adjustment operation so as not to swing the suspended load at the time of stop. I needed to. SUMMARY OF THE INVENTION It is an object of the present invention to provide a crane hoisting stop control device that stops the boom hoisting drive without leaving the swing of a suspended load hung at the tip of the hoistable boom.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, a crane hoisting / stopping control device of the present invention is a crane hoisting / stopping control device in which a suspended load is hung on the tip of a boom that can be raised / lowered. Detection of a boom state detecting means for detecting a boom state, an undulating angular velocity detecting means for detecting an undulating angular velocity of the boom, and a sway radius detecting means for detecting a sway radius of a suspended load suspended at a tip of the boom. In addition to placing the container, the regulating means that regulates the boom undulation drive is arranged,
Limit state calculating means for determining the limit state of the boom hoisting drive; and margin for calculating a marginal movement amount of the boom tip until the boom reaches the limit state by the hoisting drive based on signals from the boom state detecting means and the limit state calculating means. Amount calculating means, the undulating angular velocity detected by the undulating angular velocity detecting means, the swing radius of the suspended load detected by the swing radius detecting means,
And a deceleration signal calculating means for obtaining a deceleration signal of the boom tip for stopping the boom undulation drive based on a signal from the boom state detection means without leaving a swing of the suspended load, and stopping from the start of deceleration by the deceleration signal. By the stop amount calculating means for obtaining the stop movement amount of the boom tip, and when the marginal movement amount obtained by the margin amount calculation means reaches the stop movement amount obtained by the stop amount calculation means, the boom hoisting drive is performed. An arithmetic and control unit comprising control means for outputting a deceleration signal to the regulating means so as to decelerate with the deceleration signal obtained by the deceleration signal calculation means is arranged.

[0009]

The lifting / lowering stop control device for a crane according to the present invention having the above-described configuration is provided with an arithmetic and control unit that operates as follows. The up / down drive of the boom can be stopped without leaving vibration. That is, the margin movement amount of the boom tip until the boom reaches the limit state by the up-and-down driving is obtained by the margin amount calculation unit based on signals from the boom state detection unit and the limit state calculation unit. A deceleration signal of the boom tip for stopping the boom undulation drive without leaving the swing of the suspended load based on the signals from the respective undulation angular velocity detection means, runout radius detection means, and boom state detection means. The amount of stop movement of the tip of the boom from the start of deceleration to the stop is calculated by the deceleration signal by the deceleration signal. When the surplus movement amount obtained by the surplus amount calculation means reaches the stop movement amount obtained by the stop amount calculation means, the control means slows down the boom undulation drive by the deceleration signal obtained by the deceleration signal calculation means. A deceleration signal is output to the regulating means, and the boom hoisting drive is decelerated to stop the boom hoisting drive without leaving a swing of the suspended load when the limit state is reached. Thus, the deceleration signal of the boom tip for stopping the boom without leaving the swing of the suspended load is obtained, and the deceleration signal is used to decelerate the boom up and down motion to stop the boom. In addition, the boom up / down drive can be stopped. Moreover, when the vehicle is decelerated and stopped by the deceleration signal, the boom up / down drive can be decelerated and stopped at a stage that does not deviate from the limit state of the boom up / down drive, so that the boom up / down drive can be safely stopped. it can.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A crane hoisting / stopping control device according to the present invention is shown in FIG. Note that the up-and-down angle detecting means 11, the length detecting means 12, and the load detecting means 13 of the telescopic boom state detecting means A described in the related art are the same. Abbreviate. Reference numeral 23 denotes an undulating angular velocity detecting means for detecting the undulating angular velocity V1 of the telescopic boom (comprising an accelerometer or the like).
It is. Reference numeral 24 denotes a run-out radius detecting means for detecting a run-out radius l of a suspended load suspended at the tip end of the telescopic boom. What is necessary is just to detect the amount of the wire rope 10 to the hanger, and it is detected by an appropriate detection means such as detecting the amount of the wire rope 10 extended from the winch 9. 25
Is a restricting means for restricting the up-and-down driving, and receives a deceleration signal from an arithmetic and control unit to be described later, and
Is control means for a control valve for controlling the operation of the control valve.

Reference numeral 26 denotes an arithmetic and control unit, which is configured as follows. Reference numeral 27 denotes a working radius calculating unit that receives a signal from the telescopic boom state detecting unit A and obtains a working radius R in consideration of the bending of the telescopic boom 2. 28 is
An actual load calculating unit that receives a signal from the telescopic boom state detecting unit A and obtains an actual load of the suspended load. Reference numeral 29 denotes limit state calculating means which receives signals from the undulation angle detecting means 11, the length detecting means 12, and the actual load calculating means 28, and obtains a limit state of the undulating drive of the telescopic boom. In this case, the limit state determined by the moment load is calculated. In this case, the limit working radius R1 which reaches the limit by the raising / lowering drive of the telescopic boom is calculated. That is, when the telescopic boom 2 is driven up and down (in this case, the telescopic boom 2 is driven down), if the telescopic boom 2 is driven up and down any further, the crane falls or the strength of the telescopic boom 2 is destroyed. Then, the critical working radius R1 at which the undulating drive can no longer be performed is determined. 30 is the limit working radius R obtained by the limit state calculating means.
This is a margin calculating means for subtracting the working radius R obtained by the working radius calculating means 27 from 1 to calculate a surplus working radius R2 (= R-R1).

Reference numeral 31 denotes a boom lifting / lowering drive which stops a boom swing based on signals from the undulation angle detecting means 11, the length detecting means 12, the undulating angular velocity detecting means 23, and the sway radius detecting means 24 without leaving swing of the suspended load. This is a deceleration signal calculating means for calculating a deceleration signal α for causing the deceleration signal α to be calculated. That is, in general, for a single pendulum, when the pendulum fulcrum B is moving at a constant velocity V in the horizontal direction while the pendulum is not vibrating as shown in FIG. It is known that when the fulcrum B is stopped at a deceleration at the indicated acceleration, the pendulum does not swing. α = V / N * T where N: natural number T: period of a single pendulum [T = 2π√ (l / g)] g: gravitational acceleration l: length of pendulum (here detected by the deflection radius detecting means 24) When this is applied to the telescopic boom 2, as shown in FIG. 3, the velocity V2 in the direction of the undulation angle at the tip of the telescopic boom 2 is equal to the undulation angular velocity V1 detected by the undulation angular velocity detection means 23. The speed V2 of the tip of the telescopic boom 2 in the direction of the undulation angle is calculated by obtaining the speed as a function of the length L of the telescopic boom 2 detected by the detection means 12. (Mounting angle speed detecting means 23 is attached to the tip of telescopic boom 2 to directly adjust the speed V2
Is not required to be obtained as a function of the length L of the telescopic boom 2 detected by the length detecting means 12. ) The speed V2 of the tip of the telescopic boom 2 in the direction of the undulation angle is calculated as the speed Vx of the tip of the telescopic boom 2 in the working radial direction, and becomes Vx = V2 * sin θ = L * V1 * sin θ. The deceleration α in the direction is obtained as α = Vx / N * T. Here, N may be set to a natural number that provides the optimum deceleration α.

Reference numeral 32 denotes a stop amount calculating means for calculating a moving amount R3 of the distal end of the telescopic boom in the working radial direction from the start of the deceleration by the deceleration signal α (deceleration acceleration) to the stop.
It can be obtained from the deceleration signal α and the speed Vx in the working radial direction at the tip of the telescopic boom as follows. That is, the moving distance R3 in the working radial direction from the start of deceleration to the stop of the end of the telescopic boom is integrated with the speed Vx (t) = Vx-αt of the front end of the telescopic boom in the working radial direction by the time N * T until the stop. do it. Thus, R3 can be obtained from R3 = Vx * N * T- 1/2 * α * N 2 * T 2 becomes deceleration signal alpha and work radial velocity Vx in telescopic boom tip.

Numeral 33 denotes control means, which controls the marginal movement amount R2 obtained by the margin amount calculation means 30 to the stop amount calculation means 3.
When the stop movement amount R3 obtained in step 2 is reached, the up-down driving of the telescopic boom is performed by the deceleration signal α obtained by the deceleration signal calculating means 31.
Is a means for outputting a deceleration signal to the restricting means 25 so as to decelerate the motor.

The hoisting / falling stop control device for a crane according to the present invention having the above-described structure operates as follows. The work radius calculation means 27 calculates the current work radius R of the telescopic boom 2 by receiving signals from each detection means of the boom state detection means A. The limit state calculation means 29 receives signals from the work radius calculation means 27 and the actual load calculation means 28, and obtains a limit work radius R1. The surplus amount calculating means 30 obtains the working radius R2 from the current state of the telescopic boom 2 to the limit from the values of the working radius R and the limit working radius R1.

In the deceleration signal calculating means 31, the undulation angle detecting means 11, the length detecting means 12, the undulating angular velocity detecting means 23,
And a deceleration signal α for stopping the boom undulation drive without leaving the swing of the suspended load based on the signal from the swing radius detecting means 24. The stop amount calculating means 32 obtains a moving amount R3 in the working radial direction of the distal end of the telescopic boom from when the deceleration signal α (deceleration acceleration) starts to decelerate to when the boom stops.

In the control means 33, the margin calculating means 3
When the surplus movement amount R2 obtained at 0 reaches the stop movement amount R3 obtained at the stop amount calculation means 32, the up-and-down driving of the telescopic boom is decelerated by the deceleration signal α obtained by the deceleration signal calculation means 31. The deceleration signal is output to the means 25. The regulating means 25 calculates the deceleration signal α obtained by the deceleration signal calculating means 31.
Is output from the control means 33, and the undulating drive of the telescopic boom 2 is gradually decelerated and finally stopped.

In this way, the deceleration signal α of the boom tip for stopping the telescopic boom 2 without leaving the swing of the suspended load is obtained, and the deceleration signal α is used to decelerate the undulating movement of the telescopic boom 2 and stop it. Therefore, the up / down driving of the telescopic boom 2 can be stopped without leaving the swing of the suspended load. Moreover,
When the vehicle is decelerated by the deceleration signal α and stopped, the undulating drive of the telescopic boom 2 can be decelerated and stopped at a stage where the limit of the undulating drive of the telescopic boom 2 is not deviated. Can be stopped.

In the above embodiment, the current working radius R
The marginal work radius calculating means 30 calculates the marginal work radius R2 from the limit work radius R1 and the stop movement amount R3 as the movement amount in the work radial direction. It goes without saying that the processing method can be similarly implemented.

In the above embodiment, the limit state calculating means 29 calculates the limit state determined by the moment load acting on the telescopic boom 2 based on the detection signal from the boom state detecting means A. Not only the detection signal from the state detection means A but also the signals from the outrigger extension state detection means d1 to d4 for detecting the extension state of the outriggers 5a, 5b, 5c, and 5d as shown by the dashed line in FIG. Alternatively, the limit state may be calculated.

Furthermore, the limit state is not determined only by the moment load acting on the telescopic boom 2. For example, as shown in FIG. 1, there is a limit state determined by a head limit H, a working radius limit R, an undulation angle limit θ1 (upper undulation angle), θ2 (lower undulation angle), and the like at the tip of the telescopic boom 2. In this case, the head limit H and the undulation angle limit θ
1, the limit state based on θ2 may be temporarily replaced with the working radius, and the working radius that reaches the current state of the telescopic boom 2 as soon as possible may be output from the limit state calculating means 29 as the limit working radius R1. In addition, since the limit state may reach the limit state when the telescopic boom 2 is raised, as well as when the telescopic boom 2 is laid down, the detection signals from the undulation angle detecting means 11 are successively taken to determine the undulating operation direction of the telescopic boom 2. The working radius that can be reached earlier depending on the operation direction may be output from the limiting state calculating means 29 as the limiting working radius R1.

Next, in the above-described embodiment, the case where the undulating angular velocity is detected by the accelerometer or the like attached to the telescopic boom 2 as the undulating angular velocity detecting means 23 has been described. Alternatively, the speed detected by the speed detector may be obtained as the speed of the tip of the telescopic boom 2 in the direction of the undulation angle. Further, in the above-described embodiment, the boom is described as a telescopic boom. In this case, the boom state detection means A does not require the length detection means 12. Further, it goes without saying that the control unit 14 may be arranged in the arithmetic and control unit 26 of the present invention in order to arrange the angle indicator 20 and the moment indicator 21 described in the related art.

[0023]

The crane hoisting / stopping control apparatus of the present invention having the above-described structure can stop the boom hoisting drive without leaving the swing of the suspended load. Moreover, when the vehicle is decelerated and stopped by the deceleration signal, the boom up / down drive can be decelerated and stopped at a stage that does not deviate from the limit state of the boom up / down drive, so that the boom up / down drive can be safely stopped. it can.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a crane hoisting / stopping control device of the present invention.

FIG. 2 is an explanatory diagram of a simple pendulum.

FIG. 3 is an explanatory view of a pendulum by a suspended load suspended at the end of a boom.

FIG. 4 is an explanatory view of a conventional safety device for a mobile crane.

FIG. 5 is an explanatory diagram illustrating a mobile crane.

[Explanation of symbols]

 A boom state detecting means 2 boom 23 undulating angular velocity detecting means 24 deflection radius detecting means 25 regulating means 26 arithmetic control unit 29 limit state calculating means 30 margin calculating means 31 deceleration signal calculating means 32 stop amount calculating means 33 control means

Claims (1)

(57) [Claims] 1. A lifting / lowering stop control device for a crane in which a suspended load is hung on a tip of a boom which can be raised / lowered, comprising: a boom state detecting means for detecting a boom state; Detecting means, arranging each detector of oscillating radius detecting means for detecting the oscillating radius of the suspended load suspended at the end of the boom, and arranging regulating means for regulating the boom undulating drive, Limit state calculation means for determining the limit state of the boom state detection means and a margin amount calculation means for obtaining a marginal movement amount of the boom tip until the boom reaches the limit state by the hoisting drive by a signal from the limit state calculation means, Based on the undulating angular velocity detected by the undulating angular velocity detecting means and the swing radius of the suspended load detected by the sway radius detecting means and the signal from the boom state detecting means. A deceleration signal calculating means for obtaining a deceleration signal of the boom tip for stopping the boom up / down driving without leaving the load swing, and a stop for obtaining a stop movement amount of the boom tip from deceleration start to stop by the deceleration signal. An amount calculating means, and when the surplus moving amount obtained by the surplus amount calculating means reaches the stop moving amount obtained by the stop amount calculating means, the boom undulation drive is decelerated by the deceleration signal obtained by the deceleration signal calculating means. And a control means for outputting a deceleration signal to the restricting means.