JPH05229797A - Control method of load balancing device - Google Patents

Abstract

PURPOSE:To improve the safety of a device and make it safe and easier to use by making time deviation between the memorized value and the detected value of a load weight to the elevating command of an elevating mechanism and calculating a gain corresponding to its bigness and amplifying the elevating command by the gain signal so as to chance an elevating speed. CONSTITUTION:A load balancing mechanism provides a mechanism elevating a load, a motor 2 for driving an elevation driving the elevating mechanism of this load, a speed detector 18 for detecting the speed of the elevating mechanism, the speed control means of the elevating mechanism, the load weight detector 14 of a load and the weight memory part 16 of a load and acts making the memory value of a load weight to a target. A calculation part 10 for calculating a gain corresponding to the bigness of this elevating command by making the deviation between the memory value of the load weight and a detection value to the elevating command of the elevating mechanism is provided and the elevating command is amplified by an amplifier 23 in which the gain is changed by a gain signal from the calculation part 10 and the elevating speed of the elevating mechanism is changed by making the output of this amplifier 23 to the elevating command.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a hoisting type or parallelogram type link mechanism as an actuator (for example, an electric motor).
The present invention relates to a method for controlling a load balancer that elevates and lowers a load by using.

[0002]

2. Description of the Related Art As a method of controlling a load balancing device of this type, there is an actual Kaihei 1-303297 (a control circuit for a balancing device).

The device of Japanese Utility Model Laid-Open No. 1-303297 is a balanced cargo handling device for raising and lowering a load by using a hoisting mechanism using an actuator (electric motor), and an elevating mechanism for raising and lowering the load, and a drive circuit for driving the mechanism. , A speed commander for a worker to input a speed command, a load detector for detecting a load of a load, a speed detector for detecting a hoisting speed, a position detector for detecting a position of a hoisting mechanism, and each detector In an equilibrium loading and unloading device equipped with an arithmetic circuit that outputs an input signal to a drive circuit of a lifting mechanism based on the detection signal of the lifting mechanism, the lifting detector moves up and down based on the load detection signal of the load detector, a previously stored weight stored value, and a lifting speed. A calculation unit for calculating a speed command for the mechanism is provided, and is configured to be sent to the drive circuit of the lifting mechanism so that the load can be lifted and lowered with a light force. Deviation multiplied by a gain circuit and the lifting mechanism is small when the low speed, when high speed is provided an adder for adding the output of the circuit of the circuit as well as the both multiplied by the large velocity gain to the lifting speed command.

A signal obtained by multiplying the speed signal of the lifting mechanism by a small speed gain when the speed of the lifting mechanism is low, and a large speed gain when the speed is high, and by multiplying the deviation signal between the stored value of the load weight and the detected value by the gain. By adding, the speed gain is increased when moving the load at high speed to reduce the operating force, and the speed gain is decreased when moving at low speed so that the lifting mechanism can be operated with an appropriate operating force. is there.

[0005]

In the load balancing device of the prior art, the speed command to the lifting device is based on the stored value of the load weight suspended by the lifting mechanism, and the deviation between the stored value of the weight and the detected value. Is operating as a command.
At this time, the value corresponding to the speed feedback signal of the lifting mechanism is further added to the speed command to obtain the actual speed command of the lifting mechanism, so even when the difference between the stored value of the load weight and the detected value is zero. Since the speed feedback signal of the lifting mechanism is added to the command, the lifting mechanism continues to operate without stopping. For this reason, the operator who is actually operating needs to apply a force in the opposite direction to the load in order to stop the lifting mechanism, and adds the deviation between the stored value of weight and the detected value based on the moving speed. It must be stopped by changing the polarity to the same value.

Further, when the lifting mechanism is moved while the hand is released from the load, the difference between the stored value of the load weight and the detected value becomes zero.
Since the speed feedback signal is not zero, the elevating mechanism continues to operate without stopping, and in some cases, the device may be destroyed or it may be a very dangerous situation for the operator.

The present invention has been made to solve the above problems, and reduces the operation force when the load is moved at high speed or low speed, and further, even when the operator releases his hand, the device and the operator It is also an object of the present invention to provide a safe load balancing device.

[0008]

In order to achieve the above object, a load balancing apparatus according to the present invention comprises a load lifting mechanism for lifting a load, a drive mechanism for driving the lifting mechanism, and a load for detecting the weight of the load. A detector, a weight storage unit that stores the detected load weight, a speed detector that detects the speed of the load lifting mechanism, and a speed command device that is connected to an operating lever for the operator to command the speed of the lifting mechanism. A deviation calculator for calculating the deviation between the load detector signal and the weight storage signal, a calculator for calculating each of the signals and outputting a speed command to the drive unit of the lifting mechanism, and an output from the calculator It has a speed command calculation unit that performs a calculation to change the gain or change the added value according to the signal, and controls the lifting speed of the load balancing mechanism by this output signal.

In addition, a gain calculation unit for calculating a gain for the calculation unit based on the magnitude of the speed detector signal instead of the output signal from the calculation unit is provided, and the lift mechanism is moved up and down corresponding to the lifting speed of the lifting mechanism. The calculation unit that calculates the speed controls the lifting and lowering of the load balancing mechanism.

[0010]

When the elevating mechanism suspends a load to perform the elevating operation, the elevating speed is output from the speed command device as a speed command signal to the speed computing section in response to a change in the operation amount of the operation lever by the operator. And the suspended load weight is detected by the load detector, the load weight is stored in the weight storage unit, and the deviation between the stored weight and the detected weight is input to the arithmetic unit as a speed command signal to operate. ..

In the operation mode in which the command from the speed commander is valid, a speed command signal proportional to the operation amount of the operating lever outputs a lift command to the drive unit of the lift mechanism, and the lift mechanism outputs the lift command. Along with this, the lifting operation is performed.

Further, in the equilibrium mode in which the lifting / lowering operation is performed with the weight stored in the weight storage unit as a target, the deviation between the stored load weight and the load weight detected by the load detector is taken, and this deviation is used as a lifting / lowering command. Moves up and down. At this time, the command to the lifting mechanism operates the deviation signal as a basic lifting signal, but in the speed command calculation unit that receives the deviation signal as an input, the gain is changed according to the magnitude of the basic lifting signal, By adding a value corresponding to the magnitude of the lifting signal, the apparent gain is increased and the operating force is lightened when moving the lifting mechanism at high speed, and the gain is similarly decreased when moving at low speed. Allows the lifting mechanism to be operated with an appropriate operating force.

Further, the command to the elevating mechanism is operated by using the deviation signal as the elevating command, and the gain of the arithmetic unit for giving the elevating command is set in accordance with the magnitude of the signal from the speed detector for detecting the speed of the elevating mechanism. It is possible to operate the elevating mechanism with an appropriate operating force by changing the gain and increasing the gain to lighten the operating force when moving the elevating mechanism at high speed, and reducing the gain when moving the elevating mechanism at low speed.

By the above, in the equilibrium mode in which the load weight is memorized and operated, the operator works so that the force applied to the load by the operator corresponding to the moving speed of the lifting mechanism becomes appropriate, and the load handling is further improved. By adopting an easy and safe control method, it is possible to avoid a situation that poses a danger to the operator.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS.

The parallel link type lifting mechanism 1 is driven up and down by a lifting drive motor 2 and a gear mechanism 3, and a lifting tool 5 is provided at the tip thereof to suspend a load 4. Further, the operating lever 7 of the speed command device 6 that commands the lifting speed of the lifting mechanism 1
Is provided, and the speed command signal S from the speed command device 6 is provided.
Is input to the determination unit 8, is digitally converted by the V / F converter 9, and is input to the target counter 12 through the mode selection unit 11 of the calculation unit 10, and is input to the position calculation unit 13 as the target position of the lifting mechanism 1. It

Further, the suspender 5 is attached to the tip of the lifting mechanism 1 via the load detector 14, and the weight 4 of the load W is detected by the load detector 14, and the load signal WA is A / D.
The converter 15 digitally converts it into a load signal WB, which is input to the weight storage 16 and the deviation detector 17.

The judgment unit 8 receives the judgment signal SH from the position calculation unit 13 of the calculation unit 10 and outputs a storage signal R to the weight storage unit 16. Further, the deviation detection signal 17 takes the deviation between the target weight WC from the weight storage unit 16 and the current weight WB from the load detector, and outputs the deviation signal WR to the mode selection unit 11 of the calculation unit 10.

The ascending / descending speed of the ascending / descending mechanism 1 is the speed detector 1
8 and is fed back to the drive unit 19 as a speed feedback signal SF, and the speed of the lifting mechanism 1 is controlled. Further, the position of the elevating mechanism 1 is detected by the position detector 20 and input to the current counter 21 of the arithmetic unit 10, and the elevating mechanism 1
Is input to the position calculation unit 13 as the current position of. The target position is input from the target counter 12 to the position calculation unit 13, and a speed command for the lifting mechanism 1 is calculated, and is input to the D / A conversion unit 24 via the amplifier 23 of the speed command calculation unit 22 and after analog conversion, The speed command signal XO is output to the drive unit 19 of the lifting mechanism 1. In addition, the position calculation unit 1
The speed command signal SO from 3 is also input to the gain calculator 25, which calculates the gain corresponding to the speed of the lifting mechanism 1 and gives the gain signal G to the amplifier 23. Next, the operation of the control circuit of the load balancing device according to the present invention will be described.

When a speed command signal S proportional to the operation amount of the operation lever 7 is output from the speed command device 6 by an operator operating the operation lever 7, the V / F converter 9 converts the speed command signal S into a digital value and calculates the value. The calculation is performed by the unit 10 and the drive signal X
By outputting O to the drive device 19 of the drive motor 2, the elevating mechanism 1 performs the elevating operation at a speed proportional to the operation amount of the operation lever 7.

At this time, the speed command signal S from the speed commander 6 connected to the operation lever 7 is supplied to the calculation unit 10 as V /
The command signal SA digitally converted by the F converter 9 is input through the mode selection unit 11, and this command signal SA is input to the target counter 12 that gives a position target to the lifting mechanism 1, and the output of the target counter 12 is the lifting mechanism 1. Is input to the position calculation unit 13 as the target position. Further, the current position of the lifting device 1 is input from the position detector 20 as a position detection signal XF to the current counter 21 to count the current position, and the current position signal X of the lifting mechanism 1 is used as the position calculation unit 13.
Entered in.

The position calculator 13 constantly compares and calculates the target position from the target counter 12 and the current position from the current counter 21, outputs a basic lifting command to the lifting mechanism 1 and amplifies by the amplifier 23, and then D The / A converter 24 performs analog conversion and outputs a drive signal XO to the drive device 19, whereby the drive motor 2 of the lifting mechanism 1 is driven and the lifting mechanism 1 is driven up and down.

The elevating mechanism 1 is driven up and down based on the drive signal XO output from the position calculating section 13, is detected by the ascending / descending speed detector 18, and is fed back to the drive section 19 as a speed feedback signal SF. The speed of is controlled.

Initially, the raising and lowering of the raising and lowering mechanism 1 is selected to the operation mode side which is performed by the operator operating the operation lever 7, and the mode conversion section 11 is selected to the operation mode side and the speed proportional to the operation of the operation lever 7. Is driven up and down. Here, when the speed command signal S becomes minute and the change in the position of the lifting mechanism 1 becomes minute, the judgment signal SH is output from the position calculation unit 13 and the judgment unit 8 outputs the weight storage signal R to the weight storage unit 16. Then, the weight storage unit 16 stores the weight of the load 4 suspended by the lifting mechanism 1. When the weight storage unit 16 stores the load 4 weights, the mode conversion unit 11 is selected to the balanced mode side and the operation mode shifts to the balanced mode.

The weight of the load 4 hung on the lifting mechanism 1 is detected by the load detector 14 and input as a load signal WA to the D / A converter 15 to be converted into an analog signal to become a load signal WB. Stored as 4 weights.
Here, the weight stored in the weight storage unit 16 is input to the deviation detection unit 17 as the target weight WC to be lifted by the lifting mechanism 1, and is constantly compared with the current load 4 weight. Deviation detection unit 1
The weight deviation obtained in 7 is used as a deviation signal WR in the calculation unit 1
It is input to 0 to drive the lifting mechanism 1 up and down.

At this time, the ascending / descending speed of the ascending / descending mechanism 1 is calculated by the position calculator 13 of the calculator 10 based on the weight deviation obtained by the deviation detector 17, and this output is further calculated by the speed command calculator 22. After being amplified by the amplifier 23, it is input to the driving device 19 via the D / A converter 24 to drive the lifting mechanism 1 up and down. Here, as the amplification gain of the amplifier 23 of the speed command calculation unit 22, the gain calculation unit 25 calculates the gain corresponding to the ascending / descending speed by the output of the position calculation unit 13. The gain signal G is given as a gain to the amplifier 23 of the speed command calculator 22. Here, in the gain calculator 24,
A gain curve of the ascending / descending speed and the gain as shown in FIG. 3 is calculated corresponding to the ascending / descending command speed for the ascending / descending mechanism 1, and works to change the gain of the amplifier 23.

As a result, in the operation of the elevating mechanism 1, the operating force of the operator changes depending on the elevating speed, and when a large force is applied to the load, that is, when moving at a high speed, the gain becomes large and the operating force is light and the operating force is too small. When no force is applied, that is, when moving at a low speed, the gain becomes small and the lifting mechanism can be operated with an appropriate operating force.

As described above, according to the present embodiment, in the equilibrium mode in which the load weight is stored and operated, the force applied by the operator to the load becomes appropriate in accordance with the moving speed of the lifting mechanism. Therefore, the force applied to the load suspended by the lifting mechanism becomes appropriate. Therefore, when the force applied to the load suspended by the lifting mechanism is large and you want to move quickly, a light operation force is sufficient, and when the force applied to the load is small and you want to move slowly, it is an appropriate operation force and is easy for the operator to handle. Become a device. Further, when the operator's operating force is exhausted, the lifting / lowering command disappears and the operation is stopped. Therefore, a safer control method is provided, the safety of the apparatus is improved, and the operator can provide a safe and easy-to-use load balancing apparatus. (Other embodiments)

If the minimum value Gmin of the gain curve is made variable with the gain curve as shown in FIG. 3 being used, it is possible to change the operating force at low speed. Furthermore, a gain curve like a combination of a plurality of straight lines can be used as shown in FIG. Further, a second embodiment will be described with reference to FIGS.

The structure of the speed command calculation unit 22 is changed as shown in FIG. 5, and the output of the position calculation unit 13 of the calculation unit 10 is input to the amplifier 23 and the addition signal calculator 26 of the speed command calculation unit 22 to add the addition signal. The arithmetic unit 26 performs an arithmetic operation based on the input speed command signal so as to obtain an output curve as shown in FIG. 6, and adds it to the output of the amplifier 23 of the speed command arithmetic unit 22 and outputs it to the D / A converter 24. By outputting, the lifting mechanism 1
The ascending / descending speed of addition to the basic ascending / descending command
6 outputs are added. Therefore, when a large force is applied to the load, that is, when moving at a high speed, the speed becomes higher and the operating force becomes lighter. Also, when you do not apply too much force to the load,
That is, since the added value is small when moving at a low speed, the lifting mechanism can be operated with an appropriate operating force. Also in this embodiment, it is possible to form an output curve as a combination of a plurality of straight lines as shown in FIG. Next, a third embodiment will be described with reference to FIG.

The modification of the first and second embodiments is as follows.
The target position is input from the target counter 12 to the position calculation unit 13, the speed command for the lifting mechanism 1 is calculated, and the amplifier 30
After being input to the D / A converter 31 via the analog conversion,
The speed command signal XO is output to the drive unit 19 of the lifting mechanism 1. Further, the speed feedback signal SF is calculated by the gain calculation unit 3
The gain signal G is also input to 2 and the gain corresponding to the speed of the elevating mechanism 1 is calculated to give the gain signal G to the amplifier 30.

Then, the position calculator 13 compares and calculates the target position from the target counter 12 and the current position from the current counter 21, outputs a lift command to the lift mechanism 1, and amplifies by the amplifier 30, The D / A converter 31 performs analog conversion and outputs a drive signal XO to the drive device 19 to drive the drive motor 2 and drive the elevating mechanism 1 up and down.

In this way, the ascending / descending speed of the ascending / descending mechanism 1 is detected by the speed detector 18 and input to the gain calculator 24, and the gain corresponding to the ascending / descending speed is calculated. The gain signal G calculated by the gain calculator 24 is calculated by the calculator 10
Is given to the amplifier 22 as a gain. Therefore, in the gain calculation unit 24, the gain calculation unit 24 corresponds to the ascending / descending speed of the ascending / descending mechanism 1.
A gain curve of the ascending / descending speed and the gain as shown in (3) is calculated and works to change the gain of the amplifier 22.

As a result, in the equilibrium mode in which the load weight is memorized and operated, the force applied by the operator to the load is adjusted so as to correspond to the moving speed of the elevating mechanism. When the speed is early, the operation force is light, and when the speed is slow, the operation force is moderate and the device is easy for the operator to handle. Further, when the operator's operating force is exhausted, the lifting / lowering command is stopped and the operation is stopped, so that the control method becomes safer, the safety of the apparatus is improved, and the operator can provide a safe and easy-to-use load balancing apparatus.

[0035]

As described above, by carrying out the present invention, the force applied by the operator to the load becomes appropriate in accordance with the moving speed of the lifting mechanism in the balance mode in which the load weight is stored and operated. Since it works like this, when the force applied to the load suspended by the lifting mechanism is large and it is desired to move quickly, it is a light operation force, and when the force applied to the load is small and it is desired to move slowly, the operation force is moderate. When the moving speed of the lifting mechanism is fast, the operating force is light, and when it is slow, the operating force is moderate.

Furthermore, since the operating characteristics can be changed by the load and the operator, the operator can easily handle the apparatus. Further, when the operating force by the work is lost, the lifting / lowering command disappears and the operation is stopped. Therefore, a safer control method is provided, the safety of the device is improved, and a worker can provide a safe and easy-to-use load balancing device.

[Brief description of drawings]

FIG. 1 is a structural diagram of an elevator showing a first embodiment of the present invention,

FIG. 2 is a control block diagram of the first embodiment of the present invention,

FIG. 3 is an explanatory diagram of a gain curve showing the ascending / descending speed and the gain characteristic of the first embodiment of the present invention,

FIG. 4 is an explanatory diagram of a gain curve showing the characteristics of the lifting speed and the gain according to the first embodiment of the present invention,

FIG. 5 is a control block diagram showing a configuration of a speed command calculation unit according to a second embodiment,

FIG. 6 is an explanatory diagram of a gain curve showing the characteristics of the elevation command and the gain of the second embodiment,

FIG. 7 is an explanatory diagram of a gain curve showing the characteristics of the elevation command and the gain of the second embodiment,

FIG. 8 is a view of the third embodiment corresponding to FIG.

[Explanation of symbols]

1 ... Lifting mechanism, 2 ... Lifting drive motor, 4 ... Load, 6 ... Speed commander, 7 ... Operating lever, 8 ... Judgment part, 9 ... V / F converter, 10 ... Calculation part, 11 ... Mode selection part , 12 ... Target counter, 13 ... Position calculation unit, 14 ... Load detector, 15 ... A / D converter, 16 ... Weight storage unit, 17 ... Deviation detection unit, 18 ... Velocity detector, 19 ... Driving device, 20 ... Position detector, 21 ... Current counter, 22 ... Speed command calculation unit, 23, 30 ... Amplifier, 24, 31 ... D /
A converter, 25, 32 ... Gain calculator, 26 ... Addition signal calculator.

Claims (3)

[Claims] 1. A mechanism for moving a load up and down, a means for driving the load lifting mechanism, a means for detecting the speed of the lifting mechanism,
A speed control means of the lifting mechanism, a means for detecting the weight of the load, a means for storing the weight of the load, and a load balancer that operates with the stored value of the load amount as a target. The deviation of the value is used as the lifting command of the lifting mechanism, and the lifting command is amplified by an amplifier that has a calculation unit that calculates a gain corresponding to the magnitude of the lifting command and that changes the gain with a gain signal from the calculation unit. A method of controlling a load balancing device, characterized in that the output of this amplifier is used as a lift command to change the lift speed of the lift mechanism. 2. A mechanism for moving a load up and down, a means for driving the load lifting mechanism, a means for detecting the speed of the lifting mechanism,
A speed control means of the lifting mechanism, a means for detecting the weight of the load, a means for storing the weight of the load, and a load balancer that operates with the stored value of the load amount as a target. The deviation of the value is used as the raising / lowering command of the raising / lowering mechanism, and an amplifier for amplifying the raising / lowering command and a calculation unit for calculating an addition signal corresponding to the magnitude of the raising / lowering command are waited for and the output of the amplifier and the output from the calculation unit are added A method of controlling a load balancing device, characterized in that the ascending / descending instruction is used as the addition signal to change the ascending / descending speed of the ascending / descending mechanism. 3. A mechanism for moving a load up and down, a means for driving the load lifting mechanism, and a means for detecting the speed of the lifting mechanism,
A speed control means of the lifting mechanism, a means for detecting the weight of the load, a means for storing the weight of the load, and a load parallel device that operates with the stored value of the load amount as a target, from the speed detection means of the lifting mechanism. And a gain control unit for giving a gain characteristic to the speed control unit, and changing the gain of the speed control unit according to the speed of the lifting mechanism.