JP6819453B2 - Electric winch device - Google Patents

Description

The present invention relates to an electric winch device used in a crane.

In a crane that uses an electric motor as a power source for a winch drum, zero speed control is performed to maintain the speed of the electric motor at zero when the object is lifted and temporarily stopped. At this time, a sudden copper loss may occur in the electric motor, the heat of the electric motor may rise, the torque of the electric motor may decrease, and the object may fall. Therefore, in the crane, in addition to the zero speed control, the brake is operated to prevent the object from falling.

In Patent Document 1, at the start of zero speed control, the gain of the integral component is set to zero, the proportional component is gradually reduced, the load holding capacity of the brake is checked, and if there is an abnormality in the brake, PI control is used. The technology for returning to the normal speed control and preventing the load from falling is disclosed.

Patent Document 2 discloses a technique for starting zero-speed control of an electric motor when a drop in load is detected when a brake is operated to hold a load.

Japanese Unexamined Patent Publication No. 2000-103592 Japanese Unexamined Patent Publication No. 6-40677

However, in Patent Document 1, the gain of the proportional component is gradually reduced during zero speed control, and the holding force due to zero speed control is gradually reduced. Therefore, in Patent Document 1, if the braking force is weakened due to a brake failure, the brake cannot sufficiently cope with the switching from the static friction force generated when the load starts to fall to the dynamic friction force. , It may not be possible to suppress the drop of load.

Further, in Patent Document 2, when the required holding force of the load increases due to the dropping situation, there is a problem that the required holding force cannot be met only by zero speed control and the drop of the load cannot be sufficiently suppressed.

An object of the present invention is to provide a winch device for a crane that suppresses the sliding of an object to be held regardless of a failure of a brake that brakes the winch drum.

The electric winch device according to one aspect of the present invention is an electric winch device provided on a crane.
With an electric motor
A current detector that detects the current flowing through the electric motor,
An angle detection unit that detects the rotation angle of the electric motor,
A winch drum that rotates by the power of the electric motor and winds up or lowers an object,
A brake that brakes the rotation of the winch drum and
A winch operation unit for operating the winch drum and
A speed calculation unit that calculates the rotation speed of the electric motor based on the rotation angle detected by the angle detection unit, and
When an operation to stop the winch drum is input to the winch operation unit, a hoisting control unit that instructs the start of zero speed control for controlling the electric motor so that the calculated rotation speed becomes zero.
When the start of the zero speed control is instructed, the braking control unit that starts the zero speed control and operates the brake,
It is provided with a torque current calculation unit that calculates the torque current of the electric motor from the detection current detected by the current detection unit at the start of the zero speed control.
When the braking control unit starts the zero speed control, the braking control unit moves in the winding direction of the electric motor with reference to the start time of the zero speed control based on the rotation angle detected by the angle detection unit. The position deviation is calculated, the sum of the torque current and the value obtained by multiplying the position deviation by a predetermined gain is calculated as the torque command value of the electric motor, and the electric motor is controlled by the calculated torque command value.

According to this configuration, when an operation to stop the winch drum is input by the winch operation unit, zero speed control is started and the operation of the brake is started. At this time, the sum of the torque current at the start of zero speed control and the value obtained by multiplying the position deviation of the motor in the winding direction by a predetermined gain is calculated as the torque command value of the motor. Therefore, even if the object slides down due to a brake failure when the brake is operated during zero speed control, the torque corresponding to the amount of the slide down is added to the torque command value to control the electric motor. .. As a result, it is possible to suppress the sliding of the object regardless of the failure of the brake.

In the above aspect, the braking control unit may increase the gain as the calculated torque current increases.

According to this configuration, the larger the torque current when the zero speed control is started, the larger the gain is. Therefore, the heavier the object, the larger the value of the torque command value according to the position deviation. Therefore, an appropriate torque can be applied according to the weight of the object, and the sliding of the object can be suppressed.

In the above aspect, a load detecting unit for detecting the load of the object is further provided.
The hoisting control unit detects the ground cutting operation and
When the ground cutting operation is detected, the braking control unit releases the brake and calculates a load torque current corresponding to the load detected by the load detection unit using the calculated torque current. Based on the rotation angle detected by the angle detection unit, the position deviation of the electric motor in the unwinding direction when the ground cutting operation is detected is calculated, and the load torque current and the position deviation are predetermined. The value added to the value obtained by multiplying the gain of the above may be calculated as the torque command value of the electric motor.

According to this configuration, when a ground cutting operation is detected, the load torque current according to the load of the object at the time of ground cutting and the value obtained by multiplying the position deviation in the winding direction by the gain are added. The value is calculated as the torque command value. Therefore, even if the object to be held slides down from the time when the ground cutting operation is detected, the torque corresponding to the amount of the slide down is added to the torque command value to control the electric motor, regardless of the brake failure. , It is possible to prevent the object to be held from falling.

In the above aspect, the load detection unit that detects the load of the object and
A boom that suspends the object from the tip,
Further provided with a boom control unit for raising and lowering the boom,
The hoisting control unit detects an undulating ground cutting operation in which the boom is raised by the boom control unit while the winch drum is stopped to lift the object.
When the undulating ground cutting operation is detected, the braking control unit calculates a load torque current according to the load detected by the load detection unit using the calculated torque current, and the angle detection unit calculates the load torque current. Based on the detected rotation angle, the position deviation of the electric motor in the unwinding direction when the undulating ground cutting operation is detected is calculated, and a predetermined gain is applied to the load torque current and the position deviation. The value added to the multiplied value may be calculated as the torque command value of the electric motor.

According to this configuration, when a undulating ground cutting operation that raises a boom and lifts an object is detected, a gain is multiplied by the load torque current and the position deviation according to the load of the object when the undulating ground cutting is performed. The value added to the value is calculated as the torque command value. Therefore, even if the object to be held slides down from the time when the undulating ground cutting operation is detected, the torque corresponding to the amount of the slide down is applied to the torque command value to control the electric motor, so that the electric motor is controlled regardless of the brake failure. It is possible to prevent the object to be held from falling.

In the above aspect, the notification unit and
Further provided with an inverter controlled by the braking control unit to drive the electric motor.
The current detection unit detects the current flowing through the inverter and the electric motor, and detects the current.
While the brake is operating, the braking control unit energizes the electric motor with a torque current lower than the torque current indicated by the torque command value using the inverter, and based on the current detection result by the current detection unit. The presence or absence of an abnormality in the electric motor and the inverter may be detected, and if the abnormality is detected, the notification unit may be notified of the prohibition of releasing the brake.

According to this configuration, when an abnormality in the electric power system of the inverter and the electric motor is detected, the prohibition of releasing the brake is issued. Therefore, when the electric power system cannot hold the object due to a failure, it is possible to prevent the operator from releasing the brake and prevent the object from falling. Further, during the operation of the brake, a torque current lower than the torque current indicated by the torque command value calculated by using the above method is applied to the electric motor, so that the electric power system is abnormal while holding the object. Can be detected.

According to the present invention, when the brake is operated at the time of zero speed control, even if the object slides down due to a brake failure, the torque corresponding to the amount of the slide down is added to the torque command value to the electric motor. Is controlled. As a result, it is possible to suppress the sliding of the object regardless of the failure of the brake.

It is external drawing of the crawler crane when the electric winch device according to the embodiment of this invention is applied to a crawler crane. It is a block diagram which shows the electric structure of the electric winch apparatus according to embodiment of this invention. It is a block diagram which shows the detail of an inverter. It is a graph which shows the relationship between the operation amount of a winch operation part, and a speed command value. It is a flowchart which shows an example of the processing of the electric winch apparatus by Embodiment 1 of this invention. It is a flowchart which shows an example of the processing of the electric winch apparatus in Embodiment 2 of this invention. It is a block diagram which shows the structure of the winch apparatus according to Embodiment 3 of this invention. It is a flowchart which shows an example of the processing of the electric winch apparatus in Embodiment 3 of this invention. It is a flowchart which shows an example of the processing of the electric winch apparatus according to Embodiment 4 of this invention.

(Embodiment 1)
FIG. 1 is an external view of the crawler crane X1 when the electric winch device according to the embodiment of the present invention is applied to the crawler crane X1. As shown in FIG. 1, the crawler crane X1 includes an upper swinging body 2 and a lower traveling body 3.

The upper swivel body 2 has a swivel frame 4 and a working device 6 mounted on the swivel frame 4. The work device 6 is for performing a hanging work (crane work) or the like of a suspended load. Specifically, the working device 6 includes a boom 8, a hanging rope 10, a hook device 12, a winch drum 112, a gantry 16, a guy line 18, an upper spreader 20, a lower spreader 22, and an undulating rope 24. And a winch 26 for undulation.

The boom 8 is undulatingly attached to the front portion of the swivel frame 4, and a hook device 12 for suspending a suspended load is suspended from the tip of the boom 8 via a suspension rope 10. The winch drum 112 is mounted on the swivel frame 4, and winds / unwinds the hook device 12 by winding / unwinding the hanging rope 10. The gantry 16 is erected on the rear portion of the swivel frame 4. One end of the guy line 18 is connected to the tip of the boom 8, and the other end is connected to the upper spreader 20. The lower spreader 22 is provided at the upper end of the gantry 16, and the lower spreader 22 and the upper spreader 20 are arranged apart from each other. An undulating rope 24 is hung around the upper spreader 20 and the lower spreader 22. The undulating winch 26 is mounted on the swivel frame 4, and the distance between the upper spreader 20 and the lower spreader 22 is reduced / expanded by winding / extending the undulating rope 24. The boom 8 is undulated as the separation distance between the two spreaders 20 and 22 is reduced / expanded.

A cabin 9 for an operator to board is provided in front of the upper swivel body 2. The cabin 9 is provided with glass on the front surface and the side surface, and the operator visually observes the surrounding environment through the glass and operates the crawler crane X1. The cabin 9 includes a seat on which the operator sits, an operation unit for operating the crawler crane X1, an accelerator operation unit for adjusting the output of the engine, a monitor displaying information such as the operating status of the crawler crane X1 and the like. Is provided.

FIG. 2 is a block diagram showing a configuration of an electric winch device according to an embodiment of the present invention. In addition to the winch drum 112 shown in FIG. 1, the electric winch device includes a winch operation unit 101, a hoisting control unit 102, a braking control unit 103, an inverter 104, an electric motor 105, a speed reducer 106, a brake 107, and an angle detection unit 108. It includes a speed calculation unit 109, a notification unit 110, and a load detection unit 111.

The winch operating unit 101 is composed of, for example, a lever-type operating device, and is used by an operator to instruct the winch drum 112 to move up or down the object. Here, the object includes the hook device 12 and the suspended load suspended by the hook device 12.

The winch operation unit 101 outputs the tilt angle of the lever with respect to the neutral position as an operation amount. Here, when the lever is operated from the neutral position to the upper side of the winding, the winch operation unit 101 outputs an operation amount indicating the tilt angle of the lever as a positive value. Further, the winch operation unit 101 outputs an operation amount indicating the tilt angle of the lever as a negative value when the lever is operated from the neutral position to the lowering side.

When the operation amount output from the winch operation unit 101 falls from outside the neutral range to within the neutral range, the hoisting control unit 102 determines that an operation for stopping the winch drum 112 has been input. In this case, the hoisting control unit 102 outputs to the braking control unit 103 an instruction to start zero speed control that controls the electric motor 105 so that the rotation speed becomes zero.

When the start of zero speed control is instructed, the braking control unit 103 starts zero speed control and operates the brake 107.

When starting the zero speed control, the braking control unit 103 is positioned in the unwinding direction of the electric motor 105 with reference to the start of the zero speed control based on the rotation angle θ detected by the angle detection unit 108. The deviation is calculated, the sum of the torque current output from the inverter 104 and the value obtained by multiplying the position deviation by a predetermined gain is calculated as the torque command value of the electric motor 105, and the electric motor 105 is controlled by the calculated torque command value. ..

Specifically, the braking control unit 103 calculates the torque command value using the following equation (1) and outputs it to the electric motor 105.

Torque command value = start torque current + k x position deviation (1)
Here, the start torque current indicates the current iq (torque current) calculated by the 3/2 converter 206 (FIG. 3) of the inverter 104 at the start of the zero speed control. The position deviation indicates the position deviation of the rotation angle θ of the rotor of the electric motor 105 in the unwinding direction with respect to the start of zero speed control. k indicates a predetermined gain. The torque command value is a signal output to the inverter 104 to adjust the torque of the electric motor 105.

As a result, when the brake 107 is operated during zero speed control, even if the object slides down due to a failure of the brake 107, the torque according to the amount of the slide down becomes the torque at the start of zero speed control. Since it is added, it is possible to suppress the sliding of the object.

The braking control unit 103 calculates the position deviation by integrating the amount of change in the rotation angle θ output from the angle detection unit 108 in the unwinding direction at regular time intervals from the start of zero speed control. do it.

On the other hand, in the normal control different from the zero speed control, the braking control unit 103 determines the speed command value according to the operation amount with reference to the graph shown in FIG. 4, and the determined speed command value and the speed calculation unit 109. The torque command value for setting the deviation from the rotation speed (actual rotation speed) of the electric motor 105 calculated in 1 to 0 is calculated by PI control and output to the inverter 104.

FIG. 4 is a graph showing the relationship between the operation amount of the winch operation unit 101 and the speed command value. The vertical axis shows the speed command value, and the horizontal axis shows the operation amount. In FIG. 4, when the speed command value is positive, the winch drum 112 rotates in the hoisting direction, for example, and when the speed command value is negative, the winch drum 112 rotates in the hoisting direction, for example.

When the operation amount of the winch operation unit 101 is in the neutral range near 0, the speed command value is 0. When the operation amount of the winch operation unit 101 exceeds the neutral range, the braking control unit 103 maintains the speed command value at the minimum speed slightly larger than 0 in both the winding direction and the winding direction until the operation amount exceeds a certain value. To do. Then, when the operation amount of the winch operation unit 101 exceeds a certain value, the braking control unit 103 linearly increases the speed command value as the operation amount increases in both the hoisting direction and the lowering direction. To determine.

Returning to FIG. 2, the inverter 104 generates, for example, three-phase AC power based on the torque command value output from the braking control unit 103 and the rotation angle θ of the electric motor 105 output from the angle detection unit 108. It is supplied to the electric motor 105. Further, the inverter 104 calculates the torque current supplied to the electric motor 105 and outputs it to the braking control unit 103. The details of the inverter 104 will be described later with reference to FIG.

The electric motor 105 is composed of, for example, a three-phase motor and is driven by a three-phase alternating current output from the inverter 104.

The speed reducer 106 is connected to the drive shaft Z1 of the electric motor 105, decelerates the torque of the drive shaft Z1 at a predetermined reduction ratio, and transmits the torque to the drive shaft Z2 of the winch drum 112.

The brake 107 is composed of, for example, a mechanical brake provided on the drive shaft Z2, and under the control of the braking control unit 103, prevents the winch drum 112 from rotating in the hoisting direction and the hoisting direction.

The angle detection unit 108 is composed of, for example, a rotary encoder or a resolver, detects the rotation angle θ of the rotor of the electric motor 105 at regular time intervals, and outputs the speed calculation unit 109 and the braking control unit 103. Here, the angle detection unit 108 may detect the rotation angle θ of the rotor with respect to the reference position. Further, the rotation angle θ takes a positive value when the electric motor 105 is rotating in the hoisting direction, and takes a negative value when the electric motor 105 is rotating in the hoisting direction.

The speed calculation unit 109 calculates the rotation speed of the electric motor 105 from the rotation angle θ detected by the angle detection unit 108 at regular time intervals, and outputs the rotation speed to the braking control unit 103. Here, the speed calculation unit 109 may calculate the rotation speed of the electric motor 105 by differentiating the rotation angle θ detected by the angle detection unit 108.

The notification unit 110 includes, for example, a monitor that displays information about the crawler crane X1 and a speaker that issues information about the crawler crane X1.

The load detection unit 111 includes a load sensor that detects the load of the object. The load detection unit 111 detects the load of the object by, for example, detecting the tension of the suspension rope 10.

The winch drum 112 includes a drive shaft Z1 of the electric motor 105 and a drive shaft Z2 connected via a speed reducer 106, and rotates for hoisting or lowering an object. The winch drum 112 winds up the hanging rope 10 by rotating in the hoisting direction, and winds up the object. Further, the winch drum 112 unwinds the hanging rope 10 by rotating in the winding down direction, which is a rotation direction opposite to the winding direction, and winds down the object.

FIG. 3 is a block diagram showing details of the inverter 104. The inverter 104 includes a current control unit 201, a 2/3 converter 202, a PWM signal generation unit 203, an inverter circuit 204, a current detection unit 205, and a 3/2 converter 206 (an example of a torque current calculation unit).

The current control unit 201 calculates the voltage command values vd and vq based on the torque command value output from the braking control unit 103 and the currents id and iq output from the 3/2 converter 206. Here, the current control unit 201 determines the d-axis current target value and the q-axis current target value from the torque command value, and sets the d-axis current target value and the d-axis current deviation, which is the deviation of the d-axis current target value and the current id. , The current target value of the q-axis and the current deviation of the q-axis, which is the deviation of the current iq, are calculated. Then, the current control unit 201 calculates the voltage command value vd of the d-axis and the voltage command value of the q-axis so that the current deviation of the d-axis and the current deviation of the q-axis become 0.

The 2/3 converter 202 coordinates the voltage command values vd and vq to calculate the voltage command values of the u phase, v phase, and w phase.

The PWM signal generation unit 203 generates PWM signals of u-phase, v-phase, and w-phase according to the voltage command values of u-phase, v-phase, and w-phase.

The inverter circuit 204 is composed of, for example, a three-phase inverter circuit, and generates u-phase, v-phase, and w-phase alternating currents according to the u-phase, v-phase, and w-phase PWM signals generated by the PWM signal generation unit 203. Then, it is supplied to the electric motor 105.

The current detection unit 205 is composed of, for example, a current sensor such as a Hall element, detects u-phase, v-phase, and w-phase alternating currents supplied from the inverter circuit 204 to the motor 105, and causes the 3/2 converter 206. Output.

The 3/2 converter 206 performs coordinate conversion of the u-phase, v-phase, and w-phase alternating currents detected by the current detection unit 205 using the rotation angle θ, and calculates the currents id and iq. Here, the current iq is output to the braking control unit 103 as a torque current.

FIG. 5 is a flowchart showing an example of processing of the electric winch device according to the first embodiment of the present invention. In this flowchart, the operation amount of the winch operation unit 101 enters the neutral range from outside the neutral range, an operation of stopping the winch drum 112 is input, and an instruction to start zero speed control is output from the hoisting control unit 102. When it starts.

First, the braking control unit 103 determines whether or not the rotation speed of the electric motor 105 calculated by the speed calculation unit 109 is equal to or lower than the reference speed V0 (S301). Here, as the reference speed V0, for example, a speed at which the speed of the electric motor 105 can be regarded as substantially 0 can be adopted.

If the rotation speed of the motor 105 is not equal to or less than the reference speed V0 (NO in S301), the process waits. On the other hand, if the rotation speed of the electric motor 105 is equal to or less than the reference speed V0 (YES in S301), the braking control unit 103 starts zero speed control (S302).

Next, the braking control unit 103 operates the brake 107 (S303). Next, the braking control unit 103 resets the timer time t to 0 (S304). Here, the timer time t is a variable for counting the execution time of the zero speed control using the equation (1).

Next, the braking control unit 103 calculates the torque command value using the above equation (1) (S305).

Next, the braking control unit 103 increases the timer time t by a predetermined value unless the position deviation of the rotor of the electric motor 105 with respect to the start of zero speed control is equal to or greater than the reference deviation L (NO in S306). The timer time t is updated (S307). Here, as the reference deviation L, a value indicating that the braking force of the brake 107 is reduced to the extent that it can be regarded as a failure can be adopted. That is, by controlling the equation (1), a torque corresponding to the amount of sliding of the object is added to the torque at the start of zero speed control, so that the sliding of the object is basically stopped. Will be done. However, if the braking force of the brake 107 is reduced, the electric motor 105 may not be able to withstand the weight of the object and the object may slide down only by the control of the equation (1). Therefore, when the position deviation after the start of the zero speed control is equal to or greater than the reference deviation L (YES in S306), the braking control unit 103 determines that the brake 107 has failed and proceeds to the process in S309.

Next, the braking control unit 103 determines whether or not the timer time t is equal to or greater than the reference time T0 (S308). Here, the reference time T0 is a predetermined time indicating the end timing of the zero speed control using the equation (1).

If the timer time t is not equal to or greater than the reference time T0 (NO in S308), the process returns to S306, and the processes of S306 to S308 are repeated.

On the other hand, if the timer time t is equal to or greater than the reference time T0 (YES in S308), the brake 107 is normal, and the process ends.

In S309, the braking control unit 103 instructs the notification unit 110 to issue a winding notification to the operator. In this case, the notification unit 110 may display a message such as "The brake may be out of order, so lower the object." On the monitor, for example. Further, the notification unit 110 may output the voice for uttering the above message from the speaker.

Next, when an operation for rotating the winch drum 112 in the downward winding direction is input by the operator using the winch operation unit 101 (YES in S310), the braking control unit 103 sets the zero speed using the equation (1). The control is switched from the control to the normal control (S311). Next, the braking control unit 103 releases the brake 107 (S312).

Next, when the braking control unit 103 detects the end of the operation of rotating the winch drum 112 in the winding down direction (YES in S313), the braking control unit 103 stops the notification unit 110 of the winding down (S314). On the other hand, when the operation of rotating the winch drum 112 in the lowering direction is not completed (NO in S313), the braking control unit 103 waits for processing.

As described above, according to the first embodiment, even if the object slides down from the start time of the zero speed control, the torque corresponding to the amount of the slide down is added to the torque at the start of the zero speed control. It is possible to suppress the slipping of objects. Further, when the object slides down even by the zero speed control using the equation (1), the operator is notified of the unwinding, so that the object can be prevented from falling.

In the first embodiment, the gain k of the equation (1) has been described as a constant, but the present invention is not limited to this, and the gain k may be calculated by k = start torque current / K0. Here, K0 is the maximum value of the assumed starting torque current. In this case, the gain k has a larger value as the starting torque current increases. As a result, the heavier the object, the larger the torque command value according to the position deviation. Therefore, an appropriate torque can be applied according to the weight of the object.

(Embodiment 2)
In the second embodiment, the hanging rope 10 is wound up while maintaining the posture of the boom 8 to prevent the object from slipping down when a ground cutting operation for lifting the object from the ground is detected. It is a feature. In the present embodiment, the same components as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the second embodiment, the hoisting control unit 102 detects the ground cutting operation. Here, when the hoisting control unit 102 detects the start of the hoisting operation from the operation amount of the winch operation unit 101, the hoisting control unit 102 monitors the change in the load detected by the load detection unit 111. Then, the hoisting control unit 102 determines that the ground cutting operation has been performed if the load change pattern shows a pattern in which the load gradually increases from 0 and stabilizes at a constant value. This is because when the ground cutting operation is performed, the load of the object gradually increases until the object moves off the ground, and when the object moves off the ground, the load of the object stabilizes at a constant value. This is a consideration.

In the second embodiment, when the hoisting control unit 102 detects the ground cutting operation, the braking control unit 103 controls the electric motor 105 using the following equation (2) or equation (3).

Torque command value = load / Kq + k x position deviation (2)
The first term of the equation (2) indicates the load torque current calculated when the ground cutting operation is detected. The load torque current is a current for generating the torque required for holding the object in the electric motor 105. In the first term, the load is the load of the object detected by the load detecting unit 111 when the ground cutting operation is detected, that is, when the object is separated from the ground. In equation (2), Kq is a coefficient for converting the load into a torque command value.

The position deviation of the second term of the equation (2) is the position deviation of the rotor of the electric motor 105 in the winding direction with respect to the detection time point of the ground cutting operation. The gain k is the same as in Eq. (1). In this case, the braking control unit 103 may calculate the position deviation by integrating the rotation angle θ in the winding direction detected by the angle detection unit 108 from the time when the ground cutting operation is detected.

As a result, even if the object slides down from the time when the ground cutting operation is detected, the torque according to the amount of sliding down is applied to the torque according to the load at the time when the ground cutting operation is detected, so that the object slides down. It can suppress the fall.

On the other hand, equation (3) is as follows.

Torque command value = k1 x speed deviation + k2 x Σ speed deviation (3)
Equation (3) shows a formula for calculating the torque command value in normal control. The first term of the equation (3) shows the proportional component of PI control, and the second term shows the integral component of PI control. The speed deviation is a deviation between the speed command value according to the operation amount shown in FIG. 4 and the actual rotation speed of the electric motor 105. k1 is the gain of the proportional component and k2 is the gain for the integral component.

Then, when the ground cutting operation is detected, the braking control unit 103 controls the electric motor 105 using the torque command value having the larger value of the equation (2) or the equation (3).

FIG. 6 is a flowchart showing an example of processing of the electric winch device according to the second embodiment of the present invention. Before the flowchart is started, it is assumed that the operation amount of the winch operation unit 101 is within the neutral range and the brake 107 is operated.

First, when the hoisting control unit 102 detects the ground cutting operation (YES in S401), the process proceeds to S402, and if the ground cutting operation is not detected (NO in S401), the process ends.

In S402, the braking control unit 103 releases the brake 107.

Next, the braking control unit 103 acquires the load of the object from the load detection unit 111 (S402). Next, the braking control unit 103 calculates the torque command value using each of the equations (2) and (3) (S404).

If the torque command value of the formula (2) is larger than the torque command value of the formula (3) (YES in S405), the braking control unit 103 outputs the torque command value of the formula (2) to the inverter 104, and the torque command value of the formula (2) is output to the inverter 104. ) Is used to control the electric motor 105 (S406). As a result, it is possible to suppress the sliding of the object when the object is lifted by the ground cutting operation.

On the other hand, if the torque command value of the formula (2) is not larger than the torque command value of the formula (3) (NO in S405), the braking control unit 103 outputs the torque command value of the formula (3) to the inverter 104. The electric motor 105 is controlled by the torque command value of the equation (3) (S407).

When the torque command value of the formula (2) is larger than the torque command value of the formula (3), if the electric motor 105 is controlled by using the torque command value of the formula (3), the object slides down. Therefore, when the torque command value of the equation (2) is large and the torque command value of the equation (3) is good, the electric motor 105 is controlled by using the torque command value of the equation (2), and the sliding of the object is suppressed. .. On the other hand, when the torque command value of the equation (3) is larger than the torque command value of the equation (2), the object does not fall off even if the electric motor 105 is controlled by using the torque command value of the equation (3). .. Therefore, when the torque command value of the equation (3) is larger than the torque command value of the equation (2), the electric motor 105 is controlled by using the torque command value of the equation (3) to improve the operability.

Next, when the operation amount of the winch operation unit 101 reaches the neutral range and the end of the winding operation is detected (YES in S408), the braking control unit 103 ends the process. In this case, since the object is in the lifted state, the braking control unit 103 may output the torque command value of the equation (1) to the inverter 104 to suppress the object from slipping off.

On the other hand, when the end of the winding operation is not detected (NO in S408), the braking control unit 103 may return the process to S404 and repeat the processes of S406 to S408.

As described above, according to the second embodiment, when the ground cutting operation is detected, the torque command value is calculated using the equation (2). Therefore, even if the object slides down from the time when the ground cutting operation is detected, the torque according to the load of the object at the time when the ground cutting operation is detected is added to the torque according to the amount of sliding down. Slip-off can be suppressed.

(Embodiment 3)
The third embodiment is characterized in that when an operation of raising the boom 8 and lifting the object from the ground (hereinafter, referred to as “undulating ground cutting operation”) is detected, the object is prevented from slipping down. To do. In the present embodiment, the same components as those in the first and second embodiments are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 7 is a block diagram showing a configuration of a winch device according to a third embodiment of the present invention. In the third embodiment, the winch device further includes a boom operation unit 121 and a boom control unit 122 as compared with the first embodiment.

In the third embodiment, the hoisting control unit 102 indicates that the operation amount output from the winch operation unit 101 is in the neutral range, and the operation amount output from the boom operation unit 121 indicates an operation for causing the boom 8. , The change of the load detected by the load detecting unit 111 is monitored. Then, the hoisting control unit 102 determines that the undulating ground cutting operation has been performed if the load change pattern shows a pattern in which the load gradually increases from 0 and stabilizes at a constant value. This is because when the undulating ground cutting operation is performed, the load of the object gradually increases until the object moves off the ground, and when the object moves off the ground, the load of the object stabilizes at a constant value. It is considered to be done.

In the third embodiment, when the hoisting control unit 102 detects the undulating ground cutting operation, the braking control unit 103 controls the zero speed by using the equation (2) or the equation (3) as in the second embodiment. I do.

Then, the braking control unit 103 controls the electric motor 105 using the equation (2) when the undulating ground cutting operation is detected, and when the winding operation is started after the undulating ground cutting operation is detected, the equation The electric motor 105 is controlled by using the torque command value of (2) or the formula (3), whichever is larger.

The boom operating unit 121 is composed of, for example, a lever-type operating device, and is used by an operator to instruct an operation of raising and lowering the boom 8. The boom operation unit 121 outputs the tilt angle of the lever with respect to the neutral position as an operation amount. Here, when the lever is operated from the neutral position to the side that raises the boom 8, the boom operation unit 121 outputs an operation amount indicating the tilt angle of the lever as a positive value, and the lever tilts the boom 8 from the neutral position. When operated to the side, the operation amount indicating the tilt angle of the lever as a negative value is output.

The boom control unit 122 includes an undulating winch 26 and an electric motor for driving the undulating winch 26, and undulates the boom 8 according to the amount of operation from the boom operating unit 121. Specifically, the boom control unit 122 includes the same components as the braking control unit 103, the inverter 104, the electric motor 105, the speed reducer 106, the brake 107, the angle detection unit 108, and the speed calculation unit 109.

The boom control unit 122 generates a torque command value according to the amount of operation output from the boom operation unit 121, and controls the electric motor that drives the undulation winch 26 to undulate the boom 8. Here, for example, when the operation amount shows a positive value, the boom control unit 122 generates a torque command value for causing the boom 8, and when the operation amount shows a negative value, the boom control unit 122 generates a torque command value for defeating the boom 8. It should be generated.

FIG. 8 is a flowchart showing an example of processing of the electric winch device according to the third embodiment of the present invention. Before the flowchart is started, it is assumed that the operation amount of the winch operation unit 101 is within the neutral range and the brake 107 is operated.

First, when the hoisting control unit 102 detects the undulating ground cutting operation (YES in S801), the process proceeds to S802, and if the undulating ground cutting operation is not detected (NO in S801), the processing ends.

Next, the braking control unit 103 acquires the load of the object from the load detection unit 111 (S802). Next, the braking control unit 103 calculates the torque command value using the equation (2) (S803). As a result, it is possible to suppress the sliding of the object when the object is lifted by the undulating ground cutting operation.

Next, the braking control unit 103 detects that the operation amount of the boom operation unit 121 is set to the neutral range and the operation amount of the winch operation unit 101 is set to a positive value, and the operator performs the winding operation of the winch drum 112. If it is determined that it has started (YES in S804), the process proceeds to S805. On the other hand, when the winding operation is not started (NO in S804), the braking control unit 103 returns the process to S803.

Since the winding operation is started in S805, the braking control unit 103 releases the brake 107.

Since S806, S807, S808, and S809 are the same as S404, S405, S406, and S407 in FIG. 4, description thereof will be omitted.

When the hoisting operation is not started while the object is lifted, the torque command value of the equation (2) is larger than that of the equation (3) because the speed deviation is 0. Therefore, in this case, the electric motor 105 is controlled by using the equation (2), and the sliding of the object is suppressed (S803). On the other hand, when the hoisting is started while the object is lifted, the speed deviation increases, so that the torque command value of the equation (3) eventually exceeds the torque command value of the equation (2). Therefore, in this case, the electric motor 105 is controlled by using the equation (3) (S809), and the sliding of the object is suppressed.

Next, when the operation amount of the winch operation unit 101 reaches the neutral range and the end of the winding operation is detected (YES in S810), the braking control unit 103 ends the process. In this case, since the object is in the lifted state, the braking control unit 103 may output the torque command value of the equation (1) to the inverter 104 to suppress the object from slipping off.

On the other hand, when the end of the winding operation is not detected (NO in S810), the braking control unit 103 may return the process to S806 and repeat the processes of S806 to S810.

As described above, according to the third embodiment, when the undulating ground cutting operation is detected, the torque command value is calculated using the equation (2). Therefore, even if the object slides down from the time when the undulating ground cutting operation is detected, the torque corresponding to the load of the object at the time when the undulating ground cutting operation is detected is added to the torque according to the amount of sliding down. It is possible to suppress the slipping of objects.

Further, when the torque command value of the equation (3) becomes larger than that of the equation (2) after the hoisting operation of the object is started, the electric motor 105 is controlled by using the torque command value of the equation (3). Toque. That is, the control is switched from the control using the equation (2) to the normal control. Therefore, the operability can be improved.

(Embodiment 4)
The fourth embodiment is characterized in that an abnormality in an electric power system including an inverter 104 and an electric motor 105 is detected while the brake 107 is operating. In the present embodiment, the same components as those in the first to third embodiments are designated by the same reference numerals, and the description thereof will be omitted. Further, FIG. 2 or FIG. 7 can be adopted as the overall configuration of the electric winch device according to the fourth embodiment.

In the fourth embodiment, the braking control unit 103 applies a torque current lower than the torque current indicated by the torque command value calculated by the equation (1) to the electric motor 105 by using the inverter 104 while the brake 107 is operating. Then, based on the current detection result by the current detection unit 205, the abnormality of the electric power system is determined.

Specifically, the braking control unit 103 outputs a torque command value smaller than the torque command value calculated using the equation (1) to the inverter 104 for a certain period of time, and the electric motor 105 winds up or winds up the object. A weak current that cannot be applied is passed through the motor 105.

Then, if the current detected by the current detection unit 205 is smaller than the reference current value, the braking control unit 103 determines that the electric power system is abnormal. Here, as a fixed period, a very short period can be adopted, for example, about 1 second to several seconds. Further, as the reference current value, a value that can be regarded as a disconnection or the like occurring in the circuit elements constituting the inverter circuit 204 and the electric motor 105 can be adopted.

Specifically, the braking control unit 103 outputs a torque command value for sequentially passing the ascending side current and the descending side current to the electric motor 105 to the inverter 104. Here, the raising side current is a current smaller than the torque current indicated by the torque command value of the equation (1), and is a current for driving the winch drum 112 in the hoisting direction. Further, the lowering side current is a current smaller than the torque current indicated by the torque command value of the equation (1), and is a current for driving the winch drum 112 in the winding direction.

Further, as the torque command value of the equation (1), the torque command value most recently calculated by the braking control unit 103 can be adopted.

In the present embodiment, the current detection unit 205 detects the current flowing through the circuit element of the inverter circuit 204 in addition to the current supplied to the electric motor 105.

FIG. 9 is a flowchart showing an example of processing of the electric winch device according to the fourth embodiment of the present invention. This flowchart may be executed, for example, when the ignition key of the crawler crane X1 is turned on, or when the brake 107 is activated by the braking control unit 103.

First, in S501, the braking control unit 103 determines whether or not the brake 107 is operating. If the brake 107 is not operating (NO in S501), the braking control unit 103 waits for processing, and if the brake 107 is operating (YES in S501), the braking control unit 103 advances the processing to S502.

In S502, if the winch operation unit 101 is not operated (YES in S502), the braking control unit 103 outputs a torque command value for passing the raising side current to the electric motor 105 to the inverter 104.

Next, the braking control unit 103 acquires the current value detected by the current detection unit 205, and if the acquired current value is smaller than the reference current value, determines that there is an abnormality in the electric power system (YES in S504). The process proceeds to S505. On the other hand, if the acquired current value is not smaller than the reference current value, the braking control unit 103 determines that the electric power system is normal (NO in S504), and proceeds to the process in S506.

In S505, the braking control unit 103 notifies the notification unit 110 of a message prohibiting the release of the brake 107. In this case, the notification unit 110 may display a message such as "Do not release the brake because there is a risk of the suspended load falling when the brake is released" on the monitor, or utter this message. The sound to be generated may be output from the speaker.

In S506, the braking control unit 103 outputs a torque command value for passing the lowering current to the electric motor 105 to the inverter 104.

In S507, the braking control unit 103 determines whether or not there is an abnormality in the electric power system, as in S504. If there is an abnormality in the electric power system (YES in S507), the braking control unit 103 notifies the notification unit 110 of a message prohibiting the release of the brake 107 (S505). On the other hand, if there is no abnormality in the electric power system (NO in S507), the process ends.

As described above, according to the fourth embodiment, when an abnormality in the electric power system is detected, the prohibition of releasing the brake 107 is issued. Therefore, when the electric power system cannot hold the object due to a failure, it is possible to prevent the brake 107 from being released by the operator and prevent the object from falling. Further, while the brake 107 is operating, a torque current lower than the torque current indicated by the torque command value calculated by the equation (1) is applied to the electric motor 105, so that the electric power system is abnormal while holding the object. Can be detected.

In the fourth embodiment, an abnormality in the electric power system may be detected by using a torque command value smaller than the torque command value calculated by the formula (2) instead of the formula (1). In this case as well, the braking control unit 103 may output a torque command value smaller than the torque command value recently calculated using the equation (2) to the inverter 104.

101 Winch operation unit 102 Winding control unit 103 Braking control unit 104 Inverter 105 Electric motor 106 Reducer 107 Brake 108 Angle detection unit 109 Speed calculation unit 110 Notification unit 111 Load detection unit 112 Winch drum 121 Boom operation unit 122 Boom control unit

Claims (5)

An electric winch device installed on a crane.
With an electric motor
A current detector that detects the current flowing through the electric motor,
An angle detection unit that detects the rotation angle of the electric motor,
A winch drum that rotates by the power of the electric motor and winds up or lowers an object,
A brake that brakes the rotation of the winch drum and
A winch operation unit for operating the winch drum and
A speed calculation unit that calculates the rotation speed of the electric motor based on the rotation angle detected by the angle detection unit, and
When an operation to stop the winch drum is input to the winch operation unit, a hoisting control unit that instructs the start of zero speed control for controlling the electric motor so that the calculated rotation speed becomes zero.
When the start of the zero speed control is instructed, the braking control unit that starts the zero speed control and operates the brake,
It is provided with a torque current calculation unit that calculates the torque current of the electric motor from the detection current detected by the current detection unit at the start of the zero speed control.
When the braking control unit starts the zero speed control, the braking control unit moves in the winding direction of the electric motor with reference to the start time of the zero speed control based on the rotation angle detected by the angle detection unit. The position deviation is calculated, the sum of the torque current and the value obtained by multiplying the position deviation by a predetermined gain is calculated as the torque command value of the electric motor, and the electric winch that controls the electric motor with the calculated torque command value. apparatus. The electric winch device according to claim 1, wherein the braking control unit increases the gain as the calculated torque current increases. Further provided with a load detection unit for detecting the load of the object,
The hoisting control unit detects the ground cutting operation and
When the ground cutting operation is detected, the braking control unit releases the brake and calculates a load torque current corresponding to the load detected by the load detection unit using the calculated torque current. Based on the rotation angle detected by the angle detection unit, the position deviation of the electric motor in the unwinding direction when the ground cutting operation is detected is calculated, and the load torque current and the position deviation are predetermined. The electric winch device according to claim 1 or 2, wherein the value added to the value obtained by multiplying the gain of is calculated as the torque command value of the electric motor. A load detection unit that detects the load of the object and
A boom that suspends the object from the tip,
Further provided with a boom control unit for raising and lowering the boom,
The hoisting control unit detects an undulating ground cutting operation in which the boom is raised by the boom control unit while the winch drum is stopped to lift the object.
When the undulating ground cutting operation is detected, the braking control unit calculates a load torque current according to the load detected by the load detection unit using the calculated torque current, and the angle detection unit calculates the load torque current. Based on the detected rotation angle, the position deviation of the electric motor in the unwinding direction when the undulating ground cutting operation is detected is calculated, and a predetermined gain is applied to the load torque current and the position deviation. The electric winch device according to any one of claims 1 to 3, wherein the value added to the multiplied value is calculated as the torque command value of the electric motor. Notification unit and
Further provided with an inverter controlled by the braking control unit to drive the electric motor.
The current detection unit detects the current flowing through the inverter and the electric motor, and detects the current.
While the brake is operating, the braking control unit energizes the electric motor with a torque current lower than the torque current indicated by the torque command value using the inverter, and based on the current detection result by the current detection unit. The electric winch device according to any one of claims 1 to 4, wherein the presence or absence of an abnormality in the electric motor and the inverter is detected, and when the abnormality is detected, the notification unit is notified of the prohibition of release of the brake.

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