JP6904845B2 - Power supply control device for vehicle cargo handling device - Google Patents

Description

According to the present invention, a loading / unloading platform is provided on the loading platform at least so as to be able to move up and down by a vehicle handling device, and a power supply control device for the vehicle handling device that drives the vehicle handling device by supplying power to an electric motor from a battery mounted on the vehicle. Regarding.

Conventionally, in a vehicle equipped with a vehicle cargo handling device, the vehicle cargo handling device is driven by supplying power to an electric motor from a battery mounted on the vehicle.

For example, a vehicle cargo handling device includes a power unit having a hydraulic pump, an electric motor for driving the hydraulic pump, and a device such as a solenoid valve, and the power supply for the power unit is supplied from an in-vehicle battery. A contactor (electromagnetic contactor) is provided in the middle of the supply. When using the vehicle cargo handling device, the vehicle cargo handling device operates when the contactor is closed by operating the remote control switch of the operator with the main switch provided in the driver's cab turned on. The main switch is turned off after using the vehicle cargo handling device.

In this way, when power supply control of the power unit is performed using the contactor, discharge occurs between the contacts when the contactor is opened and closed, the contacts of the contactor are welded, and the contact portion of the contactor is worn, resulting in the result. It reduces the life of the power supply control device.

In order to solve the above problem, in Patent Document 1, a contactor and a FET (field effect transistor) are used for power supply control of the power unit, and the power supply control is performed by shifting the opening / closing timing of the contactor and the ON / OFF timing of the FET. A technique for suppressing a decrease in the life of an apparatus is disclosed. Specifically, when the power supply to the power unit is started, the contactor is closed (ON) and then the FET is turned on, and when the power supply is stopped, the FET is turned off and then the contactor is opened (OFF). Prevent discharge (spark).

Japanese Unexamined Patent Publication No. 2008-168815

Since vehicles equipped with such a vehicle cargo handling device (for example, a truck) are used at various work sites, the power unit and electric motor of the vehicle cargo handling device are also used in a harsh environment (high temperature environment, low temperature environment, and a lot of water). Exposed to the environment, etc.). Therefore, an abnormality such as a short circuit may occur in an electric component such as an electric motor or the electric circuit itself, and if power is supplied to the electric motor with such an abnormality occurring, the component is damaged or the battery is abnormally discharged. There is a problem of causing further troubles.

The present invention has been made in view of the above problems, and provides a power supply control device for a vehicle cargo handling device capable of preventing further troubles caused by supplying power in a state where an abnormality has occurred in an electric motor or the like. The purpose.

In order to solve the above problems, in the present invention, a loading / unloading platform is provided on the loading platform so as to be able to move up and down by a vehicle handling device, and the vehicle handling device is provided by supplying power to an electric motor from a battery mounted on the vehicle. A power supply control device for a vehicle cargo handling device to be driven, which includes a power supply circuit through which a drive current from the battery flows when the electric motor is driven, a contactor arranged in the power supply circuit to open and close the power supply circuit, and the power supply. A field effect transistor arranged in the electric circuit to open and close the power feeding circuit, an open / close control unit for controlling the opening and closing of the power feeding circuit by controlling the opening and closing of the contactor and ON / OFF of the electric current effect transistor, and the above. The configuration is characterized by including a detection unit that detects a current flowing through a power feeding circuit and an abnormality determination unit that determines the presence or absence of an abnormality in the vehicle cargo handling device based on the current detected by the detection unit. There is.

According to the above configuration, the detection unit detects the current flowing through the power supply electric circuit, and the abnormality determination unit determines whether or not there is an abnormality in the power supply electric circuit based on the detected current. It is possible to prevent further problems that occur when power is supplied in a state where an abnormality has occurred in the circuit or the like.

Further, in the power supply control device, when the power supply to the electric motor is started, the open / close control unit controls to turn on the field effect transistor after a predetermined time after closing the contactor, and also controls to turn on the field effect transistor for the predetermined time. The field effect transistor is controlled to be turned on for a short time, and the abnormality determination unit determines the current detected by the detection unit and the first threshold value when the field effect transistor is turned on for a short time. , And if the detected current exceeds the first threshold value, it can be determined that there is an abnormality.

Further, in the power supply control device, when the open / close control unit can continuously rotate the electric motor by continuously supplying power to the stopped electric motor for a certain period of time or longer, the power supply control unit starts from the fixed time. It is also possible to control the electric field effect transistor to be turned on only for a short time.

According to the above configuration, if the current detected by the detection unit exceeds the first threshold value, it can be determined that there is an abnormality such as a short circuit somewhere in the power feeding electric circuit (for example, an electric motor). In this case, it is possible to notify the abnormality detection in the circuit and prompt the inspection for detecting the abnormality. Further, since the time for turning on the field effect transistor for abnormality determination may be short, it is possible to prevent an excessive current from flowing in the power feeding circuit for a long time.

Further, in the power supply control device, when the abnormality determination unit detects the current flowing through the power supply electric circuit by the detection unit during the period when the contactor is closed and the field effect transistor is OFF. It can be configured to determine that there is an abnormality.

According to the above configuration, if a current flows only when the contactor is closed, it means that an electric leakage has occurred in the field-effect transistor, and it can be determined that the field-effect transistor has an abnormality. In this case, it is possible to notify the abnormality of the field-effect transistor and prompt the replacement of parts of the field-effect transistor.

Further, in the above power supply control device, the abnormality determining unit, configured determines the presence or absence of the abnormality based on the detection value of the detection unit definitive in the period in which the field effect transistor and the contactor is closed is ON Can be.

According to the above configuration, based on the detection value of the detection unit, for example, when the detection current exceeds the second threshold value, it is determined that a serious abnormality such as inoperability of the hydraulic circuit has occurred in the power supply electric circuit. can. In this case, it is possible to notify the abnormality detection in the circuit and prompt the inspection for detecting the abnormality.

Similarly, in order to solve the above-mentioned problems, in the present invention, a loading / unloading platform is provided on the loading platform so as to be able to move up and down by a vehicle cargo handling device, and power is supplied to the electric motor from a battery mounted on the vehicle. A power supply control device for a vehicle cargo handling device that drives a vehicle cargo handling device, and a power supply circuit through which a drive current from the battery flows when the electric motor is driven, and a contactor that is arranged in the power supply circuit and opens and closes the power supply circuit. An opening / closing control that controls the opening / closing of the feeding electric circuit by controlling the opening / closing of the contactor and the ON / OFF of the electric field effect transistor arranged in the feeding electric circuit and opening / closing the feeding electric circuit. In the power supply circuit, based on the unit, the detection unit that detects the power supply status from the battery to the electric motor in response to the control of opening and closing of the power supply circuit by the open / close control unit, and the power supply status by the detection unit. It is also characterized in that it is provided with an abnormality determination unit for determining the presence or absence of an abnormality requiring parts replacement or the presence or absence of an abnormality that does not require parts replacement in the power feeding circuit .

According to the above configuration, the power supply status from the battery to the electric motor can be detected according to the open / close control of the power supply circuit by the open / close control unit, so it is only necessary to determine the presence or absence of an abnormality based on the power supply status. Instead, it can be indicated whether the target of the anomaly is one that requires replacement of parts in the power supply circuit or one that does not require replacement of parts.

Further, the power supply control device has a temporary storage unit that stores the abnormality determination result determined by the abnormality determination unit and an output unit that outputs the abnormality determination result stored in the temporary storage unit to the external analysis device. it can be to that configuration.

According to the above configuration, the abnormality detection result is stored in the temporary storage unit, and the stored abnormality detection result can be output to the external analysis device via the output unit. This makes it easy to analyze the operating status of the vehicle cargo handling device, the parts requiring maintenance, and the maintenance history using an external analysis device.

Further, the power supply control device has an input unit for inputting an abnormality detection signal of the battery, the electric motor, the contactor, and the field effect contactor, and the input unit is also connected to the temporary storage unit. The output unit can be configured to be capable of outputting the abnormality determination result and the information of the abnormality input to the input unit.

According to the above configuration, even when various abnormalities are detected, they can be output to the external analysis device via the output unit. This makes it easier to grasp the maintenance target.

The power supply control device of the vehicle cargo handling device of the present invention detects the current flowing through the power supply electric circuit by the detection unit, and the abnormality determination unit determines whether or not there is an abnormality in the vehicle cargo handling device based on the detected current. Further problems that occur when power is supplied while an abnormality has occurred in the electric motor or hydraulic circuit of the device can be prevented.

It is a top view which shows the electric wiring system of the van vehicle provided with the power supply control device of the vehicle cargo handling device which concerns on embodiment of this invention. It is a side view which shows the underfloor storage state of a loading / unloading platform. It is a side view which shows the state which pulled out the loading / unloading platform from below the floor surface of a loading platform. It is a side view showing the state where the loading / unloading platform is in contact with the ground in a substantially horizontal posture with a solid line, and the state where the platform is raised to the floor height of the loading platform with a virtual line. It is a hydraulic circuit diagram of a vehicle cargo handling device. It is a figure which shows the correlation between the solenoid valve and the operation of a vehicle handling device in the hydraulic circuit of FIG. It is an electric system circuit diagram in the power supply control device which concerns on embodiment of this invention. It is a timing chart in power supply control of an electric motor, (a) shows a controller input, (b) shows a contactor control signal, and (c) shows an FET control signal. It is a timing chart of another example in the power supply control of an electric motor, (a) shows a controller input, (b) shows a contactor control signal, and (c) shows an FET control signal. It is a timing chart of still another example in the power supply control of an electric motor, (a) shows a controller input, (b) shows a contactor control signal, (c) shows an FET control signal, and (d) shows an error detection signal. It is a block diagram which shows the structure of a control box.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 4 show the rear end portion of the van vehicle A as a vehicle having the power supply control device 10 of the vehicle cargo handling device according to the embodiment of the present invention. In the figure, 1 is a chassis frame extending in the front-rear direction of the vehicle body on both sides of the van vehicle A in the vehicle width direction, and 3 is a lateral reinforcing member 5 extending in the vehicle width direction and a vertical reinforcing member 7 extending in the front-rear direction of the vehicle body fixed to the bottom surface. It is a box-shaped loading platform, and the loading platform 3 is mounted on the chassis frame 1 via a horizontal reinforcing member 5 and a vertical reinforcing member 7.

A vehicle cargo handling device 9 is mounted at the rear end of the vehicle body of the loading platform 3 below the floor surface 3a. The vehicle cargo handling device 9 is an underfloor retractable type equipped with a three-fold type loading / unloading platform 11 in which a top panel 11a, a middle panel 11b, and a bottom panel 11c are foldable and unfoldably connected by a hinge. The loading and unloading platform 11 (bottom panel 11c) base end near both ends in the vehicle width direction is cantilevered by two sets of parallel link mechanisms 21 provided with a lift arm 13, a lift cylinder 15, a compression arm 17, and a tilt arm 19. Has been done. The loading / unloading platform 11 may be a two-sheet folding type or a one-sheet product.

Two slide rails 23 are horizontally arranged on the rear end side of the chassis frame 1 so as to extend in the front-rear direction of the vehicle body, and the slide rails 23 have a closed-section mechanism frame 25 extending in the vehicle width direction. Is supported so as to be movable in the front-rear direction of the vehicle body by the expansion and contraction operation of the slide cylinder 27. The base end of the parallel link mechanism 21 is supported on the mechanism frame 25 via the bracket 29. Then, the loading / unloading platform 11 is folded and put in and out of the lower floor surface 3a of the loading platform 3 by the expansion / contraction operation of the slide cylinder 27 (see FIGS. 2 and 3).

As shown in FIGS. 2 and 5, a power unit 35 is arranged at the left end (lower end of FIG. 1) of the mechanism frame 25 in the vehicle width direction, and the power unit 35 drives the vehicle cargo handling device 9. Actually, the power unit 35 is provided with a push button type remote control switch 36 (see FIG. 7) as a remote switch, and the power unit 35 is housed in the housing together with the push button type remote control switch 36. In 1 to 4, for convenience, these are collectively represented as a power unit 35.

As shown in FIG. 1, the power unit 35 includes a battery cord 37 as a power supply circuit for driving a motor, a chassis ground cord 39 as a ground wire, and a main power switch cord in the cab (hereinafter referred to as a main switch cord in the cab). One end side of the four electric wires of 41A and the remote control cord 43 in the refrigerator is inserted into the corrugated tube 44 and focused over a predetermined length, and in this focused state, one end of each is below the floor surface 3a of the loading platform 3. It is connected to the power unit 35. The other ends of these four focused electric wires are arranged on a stay 51 fixed to the lateral reinforcing member 5 so as to extend to the rear of the vehicle body along the vertical reinforcing member 7, and attached with a clip 53, and are attached to the chassis frame. It extends inward in the vehicle width direction of 1.

Of the above four electrical wirings, the two electrical wirings of the battery cord 37 and the main switch cord 41A in the cab are the chassis frame 1 inside the chassis frame 1 in the vehicle width direction from that point onward, as shown in FIG. It is arranged so as to extend to the front of the vehicle body along the line. Of the other two electric wires, the other end of the chassis ground cord 39 is connected to the chassis frame 1 on the left side in the vehicle width direction. The other end of the remaining one remote control cord 43 in the refrigerator is connected to a push button type remote control switch 57 for driving the vehicle handling device 9 provided in the loading platform 3.

On the other hand, as shown in FIG. 1, a battery 45 is mounted on the chassis frame 1 on the left side in the vehicle width direction toward the front of the loading platform 3, and the other end of the battery cord 37 is connected to the battery 45. The other end of the main switch cord 41A in the cab is connected to the main power switch in the cab (hereinafter referred to as the main switch in the cab) 55 provided in the cab (not shown) in front of the loading platform 3. A fuse box 47 is interposed on the other end side of the battery cord 37, and one end of another main switch cord 41B in the cab is connected to the main switch 55 in the cab, and the other end of the main switch cord 41B in the cab is connected. Is connected to the battery 45 together with the battery cord 37 via the fuse box 47.

A control box 49 as a control circuit equipped with a CPU (Central Processing Unit), a memory, and the like is attached to the left end (left end in FIG. 2) of the lateral reinforcing member 5 near the rear end of the vehicle body in the vehicle width direction via a bracket 59. The control box 49 is interposed in the main switch cord 41A in the cab.

The main switch 55 in the cab is in the OFF state when the loading / unloading work is not performed, and can be switched to the ON state by a manual operation of the operator when the loading / unloading work is started.

Then, as shown in FIG. 2, power is supplied from the battery 45 (see FIG. 1) to the power unit 35, and the operator pushes the push button type remote control switch 57 on the loading platform 3 side or the push button type remote control switch 36 on the power unit 35 side. The operation command signal is output to the power unit 35 via the control box 49 to drive the vehicle cargo handling device 9.

As described above, the vehicle handling device 9 is driven by the power unit 35, and the power unit 35 has a hydraulic circuit for driving the vehicle handling device 9. FIG. 5 shows the hydraulic circuit diagram. Specifically, in the hydraulic circuit shown in FIG. 5, pressure oil is generated by the hydraulic pump 28 driven by the electric motor 30 and sent to the lift cylinder 15 and the slide cylinder 27 via the solenoid valve 34. There is. The solenoid valve 34 is composed of four solenoid valves SOL-1 to SOL-4, and can be switched by receiving a signal from the control box 49 when the push button type remote controller switch 36 or 57 is turned on.

Although detailed description is omitted, the control box 49 controls SOL-1 to SOL-4 by the combination as shown in FIG. 6, drives the lift cylinder 15 and the slide cylinder 27, and refers to the van vehicle A. Load and unload luggage. That is, the lift cylinders 15 of the two sets of parallel link mechanisms 21 are synchronously driven to raise and lower the loading / unloading platform 11 between the ground G and the floor surface 3a height of the loading platform 3 (see FIG. 4), while the slide cylinders. 27 is driven to move the loading / unloading platform 11 in and out from the floor surface 3a below the floor surface 3a at a position slightly lower than the floor surface 3a height of the loading platform 3 (see FIGS. 2 and 3).

FIG. 7 is a circuit diagram of an electric system in the power supply control device 10 according to the present embodiment. As shown in FIG. 7, the power supply control device 10 controls the power supply from the battery 45 to the electric motor 30, and the contactor 31 as the first switch for turning on / off the power supply of the electric motor 30. And an FET 32 as a second switch. The contactor 31 is a contact-type magnetic contactor that opens and closes an electric circuit by the operation of an electromagnet, and is configured so that the contact operates only while an electromagnetic coil (not shown) is excited. The FET 32 is a non-contact type switching device. Further, as the FET 32, it is preferable to use one in which a plurality of FETs are arranged in parallel so as to be able to cope with a large current. The electric motor 30, the contactor 31, and the FET 32 are provided in the power unit 35 together with the solenoid valve 34.

The FET 32 is arranged between the battery 45 and the electric motor 30, is connected to the battery 45 via the battery cord 37, and is connected to the electric motor 30 via the connecting cord 48. The contactor 31 is connected to the electric motor 30 via the motor ground cord 46 and is grounded by the chassis ground cord 39. In the configuration of FIG. 7, the FET 32 is arranged on the upstream side (battery side) of the electric motor 30, and the contactor 31 is arranged on the downstream side (earth side) of the electric motor 30, but the present invention is limited to this. It is not something that is done. As long as the electric motor 30, the contactor 31 and the FET 32 are connected in series, the connection order thereof is not particularly limited.

Further, a shunt resistor 60 and a flow detection circuit 62 are connected to a DC circuit through which a drive current flows through the electric motor 30 in order to measure the drive current flowing through the circuit. In the example of FIG. 7, the shunt resistor 60 is connected in the middle of the battery cord 37 (between the battery 45 and the FET 32), but the present invention is not limited to this, and any of the above DC circuits. It may be connected to the position. The flow detection circuit 62 is connected in parallel with the shunt resistor 60. The flow detection circuit 62 may be provided in the power unit 35 or may be provided in the control box 49.

Further, the first signal line 40 from the control box 49 is connected to the contactor 31. The second signal line 42 from the control box 49 is connected to the FET 32. That is, the contactor 31 and the FET 32 are ON / OFF controlled by the control signals sent from the control box 49 via the first signal line 40 and the second signal line 42, respectively.

The power supply control device 10 is put into an operable state when the main switch 55 in the cab is first switched to the ON state. Then, when the push button type remote controller switch 36 or 57 is operated in this operable state, the power supply control of the electric motor 30 and the opening / closing control of the solenoid valve 34 are controlled according to the state of the vehicle cargo handling device 9 and the content of the operation instruction. (Hydraulic circuit control) is performed. Although the push button type remote control switch 57 is not shown in FIG. 7, the push button type remote control switch 57 plays the same role as the push button type remote control switch 36.

In particular, in the power supply control of the electric motor 30, when the power supply to the electric motor 30 is started, the FET 32 is turned on after a predetermined time (for example, 100 ms) has elapsed after closing the contactor 31. In this case, no current flows through the circuit when the contactor 31 is closed, but a current flows when the FET 32 is turned on. Further, when the power supply to the electric motor 30 is stopped, the contactor 31 is opened after a predetermined time (for example, 5 s) has elapsed after the FET 32 is turned off. In this case, the current is cut off when the FET 32 is turned off, and no current is flowing in the circuit when the contactor 31 is opened. That is, since the circuit current does not change when the contactor 31 is opened / closed, a discharge occurs between the contacts when the contactor 31 which is a contact type electromagnetic contactor is opened / closed, and the contacts of the contactor 31 are welded or the contactor 31 is worn. It can be prevented from occurring. As a result, it is possible to suppress a decrease in the life of the power supply control device 10.

Further, the power supply control device 10 according to the present embodiment can not only prevent discharge between the contacts of the contactor 31 by utilizing the shift between the opening and closing of the contactor 31 and the ON / OFF timing with the FET 32, but also set the timing shift period. It is characterized in that it is used to determine abnormalities. Hereinafter, this feature will be described in detail.

8A and 8B are timing charts for power supply control of the electric motor 30, where FIG. 8A shows a controller input, FIG. 8B shows a contactor control signal, and FIG. 8C shows an FET control signal. The controller input here is an input to the control box 49 generated when the push button type remote controller switch 36 or 57 is operated by an operator. That is, when the push-button remote controller switch 36 or 57 is turned ON for loading / unloading the loading / unloading platform 11 or raising the loading / unloading platform 11, the controller input is turned ON. The contactor control signal and the FET control signal are control signals sent from the control box 49 to the contactor 31 and the FET 32 via the first signal line 40 and the second signal line 42, respectively.

First, when the controller input is turned ON at time t1, the contactor control signal is turned ON at the same time, and the contactor 31 is closed. Then, at the time t2 after the time T1, the FET control signal is turned ON, the FET 32 is turned ON, and the power supply to the electric motor 30 is started.

At this time, as the first abnormality determination, when it is detected by the flow detection circuit 62 that the circuit current is flowing during the time T1 (the period when the contactor 31 is closed and the FET 32 is OFF), the abnormality is detected. It is judged to be present. That is, since the FET 32 is OFF during the time T1, if it is normal, no current flows through the power feeding electric circuit (the electric circuit through which the driving current flows when the electric motor 30 is driven). Therefore, if a current flows only when the contactor 31 is closed, it means that an electric leakage has occurred in the FET 32, and it can be determined that the FET 32 has an abnormality. In this case, it is possible to notify the abnormality of the FET 32 and prompt the replacement of parts of the FET 32. As a method of notifying the abnormality, for example, a method of providing an abnormality notification lamp at an arbitrary position of the vehicle and turning on the abnormality notification lamp can be considered. Further, when it is determined that there is an abnormality in the first abnormality determination, the contactor 31 is immediately opened when the abnormality is determined, the power supply is stopped, and the circuit is protected.

As the second abnormality determination, the FET control signal is turned on for a short time after the contactor 31 is closed at time t1 and before the FET 32 is turned on at time t2 (that is, during time T1), and the power supply current is connected. Apply current for a short time. Then, the current value detected at this time is compared with the first threshold value, and if the detected current exceeds the first threshold value, it is determined that there is an abnormality. That is, if the detected current at this time exceeds the threshold value, it can be determined that there is an abnormality such as a short circuit somewhere in the power feeding electric circuit (for example, the electric motor 30). In this case, it is possible to notify the abnormality detection in the circuit and prompt the inspection for detecting the abnormality. Further, since the time for turning on the FET 32 for determining the abnormality may be short, it is possible to prevent an excessive current from flowing in the power feeding circuit for a long time. Further, when it is determined that there is an abnormality in the second abnormality determination, the FET 32 is immediately turned off when the abnormality is determined, and the power supply is stopped to protect the circuit. At this time, the reason why the FET 32 is turned off and the power supply is stopped is as follows. First, compared to the case where the contactor 31 is opened to stop the power supply, the power supply can be stopped more quickly by turning off the FET 32, and the time for the overcurrent to flow in the circuit is shortened by that amount, which adversely affects the circuit. Can be minimized. Secondly, when the contactor 31 is opened to stop the power supply, a discharge (spark) may occur between the contacts of the contactor 31, but when the FET 32 is turned off and the power supply is stopped, the discharge (spark) is generated. Can be prevented.

When the electric motor 30 is continuously rotated from a stopped state, it is necessary to continuously supply power for a certain period of time (for example, 10 ms) or more, but in the short-time power supply in the second abnormality determination, a time shorter than this fixed time (for example). Power is supplied only for 1 ms). Even if an abnormality occurs in the circuit or the like, this short-time power supply is not performed for a long time in that state, so that parts are not damaged. The first threshold value is set as a value larger than the detected current value in the case of a normal circuit.

When the FET 32 is turned on at time t2, both the contactor 31 and the FET 32 are turned on, and the power supply to the electric motor 30 is started. At this time, it is desirable that the FET control signal PWM (pulse width modulation) control of the FET 32 in the first period to gradually increase the drive current of the electric motor 30. In FIG. 8C, the period from time t2 to t3 indicates the PWM control period. The PWM control period in FIG. 8C is an image of the control result, and in this PWM control period, the pulse width is actually changed to repeatedly turn on / off the current or voltage. It is carried out.

When the controller input is turned off at time t4, the FET control signal is turned off at the same time, the FET 32 is turned off, and the power supply to the electric motor 30 is stopped. In this case as well, it is desirable that the FET control signal PWM (pulse width modulation) control of the FET 32 to gradually reduce the drive current of the electric motor 30. In FIG. 8C, the period from time t4 to t5 indicates the PWM control period. Then, the contactor control signal is turned off at the time t6 after the time T5 from the time t5, and the contactor 31 is opened to complete the power supply control.

As a third abnormality determination, the current value detected when power is supplied to the electric motor 30 (specifically, between time t3 and t4) is compared with the second threshold value, and the detected current is the second threshold value. If it exceeds, it is determined that there is an abnormality. The second threshold value is set to a value larger than the above-mentioned first threshold value.

Here, for example, the current value at the time of normal operation of the vehicle cargo handling device 9 (when the mass of the load loaded on the loading / unloading platform 11 is within the specified mass) is 100 A or less, and the relief in the hydraulic circuit. When the current value at the time of relief of the valve 33 (see FIG. 5) is 150 A, the second threshold value is set to, for example, 200 A. The mass of the luggage and the current value are in a proportional relationship. The hydraulic circuit of the vehicle cargo handling device 9 is usually provided with a relief valve 33 for preventing the oil pressure from rising above a specified value and damaging the hydraulic circuit when the vehicle cargo handling device 9 is used in an overloaded state. When the oil pressure rises above the specified value, the relief valve 33 is opened to lower the oil pressure.

That is, when the detected current exceeds the second threshold value, it is determined that a serious abnormality such as inoperability of the hydraulic circuit (for example, failure of the relief valve) has occurred, and power is supplied to the electric motor 30 in that state. If this is continued, secondary damage such as burning of the coil in the electric motor 30 may occur. Therefore, in such a case, the control box 49 immediately turns off the FET 32 and stops the power supply to the electric motor 30. When the third abnormality determination determines that there is an abnormality, the FET 32 is turned off to stop the power supply. When the second abnormality determination determines that there is an abnormality, the FET 32 is turned off and the power supply is stopped. For the same reason as you do.

FIG. 9 is a timing chart showing another example of power supply control of the electric motor 30. In the power supply control of the present embodiment, when the power supply to the electric motor 30 is stopped, the contactor 31 is opened after a lapse of a predetermined time after turning off the FET 32. Further, the predetermined time in this case is a relatively long time (for example, 5 s), and the controller input is turned ON again after the controller input is turned OFF (time t11 or t13) and before the contactor control signal is turned OFF. It may be (time t12 or t14). This may occur when the operator repeatedly operates the push-button remote control switch 36 or 57 for a short period of time in order to fine-tune the height of the loading / unloading platform 11.

Then, if the controller input is turned ON again after the controller input is turned OFF and before the contactor control signal is turned OFF, the FET control signal is turned ON at the same time as the controller input is turned ON. As a result, when the height of the loading / unloading platform 11 is finely adjusted, the power supply to the electric motor 30 can be controlled only by turning the FET 32 ON / OFF while the contactor 31 is closed.

FIG. 10 is a timing chart showing still another example in the power supply control of the electric motor 30. The vehicle cargo handling device 9 performs various error detections, and an error detection signal from the outside as shown in FIG. 10D is also input to the control box 49. When the input error detection signal is turned ON (when some error is detected), the control box 49 immediately stops the power supply to the electric motor 30 regardless of whether the controller input is ON / OFF. You may do it. In this case, the FET control signal may be turned off at the same time as the error detection signal is turned on at time t2, and the FET 32 may be turned off immediately. Then, the contactor control signal may be turned off at the time T22 after the time T2, and the contactor 31 may be opened.

Examples of the error detection signal input externally include the following (A) to (E).
(A) Motor continuous operation abnormality: The vehicle cargo handling device 9 sets an upper limit on the continuous operation (continuous power supply) time of the electric motor 30, and if the operation is performed beyond this time, it is regarded as an abnormality. Therefore, when the controller input is ON for 20 seconds or more, it is detected as an abnormality.
(B) FET temperature abnormality: Since the FET 32 is liable to be destroyed at a high temperature, when the temperature of the FET 32 exceeds a threshold value (for example, 100 ° C.), it is detected as an abnormality. Specifically, the temperature of the FET 32 is detected by a thermistor, and when the detected temperature exceeds a threshold value, an abnormality is detected.
(C) Overcurrent detection (third abnormality determination described above): An abnormality occurs when the current value detected by the flow detection circuit 62 becomes an overcurrent (greater than or equal to the second threshold value) when power is supplied to the electric motor 30. Is detected.
(D) Power-on error: If the controller input remains ON (the operation signal of the push-button remote controller switch 36 or 57 remains ON) when the main switch 55 in the cab is ON, this is detected as an abnormality. In this case, a failure (short circuit, etc.) of the push button type remote controller switch 36 or 57 may be considered.
(E) Battery voltage abnormality: An abnormality is detected when the voltage of the battery 45 drops. Specifically, when the voltage of the battery 45 after a lapse of a predetermined time (for example, 1 s) after the electric motor 30 is turned on becomes equal to or less than a threshold value (for example, 20 V), an abnormality is detected.

In the power supply control device 10 according to the present embodiment, it is possible to prevent an overcurrent from flowing by the first to third abnormality determinations before the fuse in the fuse box 47 is blown. Therefore, after the abnormality is determined and the power supply is stopped, the fuse can be restored without replacement. In addition, the input current and input time of a fuse generally vary widely when it blows, and an overcurrent may flow for several seconds before the fuse blows, causing damage to parts and abnormal battery discharge. be. If the power supply is stopped by the first to third abnormality determinations by the power supply control device 10 according to the present embodiment, there is no such possibility.

When these abnormalities are detected, it is possible not only to perform the motor power supply stop control described above, but also to store the abnormality detection results as maintenance information and analyze the stored abnormality detection results. desirable. The configuration for that purpose will be described with reference to FIG.

FIG. 11 is a block diagram showing the configuration of the control box 49. As shown in FIG. 11, the control box 49 includes a CPU (open / close control unit, abnormality determination unit) 491, RAM (temporary storage unit) 492, ROM493, control signal output circuit 494, control signal input circuit 495, and USB interface (output). Part) 496 etc. are provided.

The CPU 491 controls the vehicle cargo handling device 9 and determines an abnormality as a main controller. Specifically, it controls the opening and closing of the contactor 31 and ON / OFF control of the FET 32, valve control in a hydraulic circuit, and a current detection circuit. An abnormality determination is made based on the current value detected by 62. The RAM 492 stores data and the like necessary for controlling and determining the CPU 491. A control program or the like is stored in the ROM 493.

The control signal output circuit 494 is a means for generating and outputting the control signal of the contactor 31 and the control signal of the FET 32. The control signal input circuit 495 is an interface for incorporating various operation inputs by the operator and the current value detected by the flow detection circuit 62 into the control box 49. The USB interface 496 is an interface for connecting a portable personal computer 70, which is a mobile information terminal, to the control box 49 and exchanging data. The mobile information terminal is not limited to the portable PC, and may be any one provided with a display device such as a PDA, a mobile phone, or a mobile tool. Further, the interface used for connecting to the mobile information terminal is not limited to USB, and any other interface can be used.

When the above-mentioned various abnormalities are detected in the vehicle cargo handling device 9, the abnormality detection results are stored in the control box 49 as maintenance information. It is assumed that the stored abnormality detection result (maintenance information) is taken out to an external device after the vehicle cargo handling device 9 has been used for a certain period of time. Therefore, if the abnormality detection result (maintenance information) is to be stored in the RAM 492, for example, it is necessary to provide the RAM 492 with a backup power supply so that the stored contents can be maintained even when the power supply is turned off. The stored abnormality detection result is configured to be read and analyzed by a portable personal computer 70 connected via the USB interface 496. Specifically, the portable personal computer 70 analyzes the stored abnormality detection result, and analyzes the operating status of the vehicle cargo handling device 9, the part requiring maintenance, and the maintenance history. Further, the portable personal computer 70 may be provided with a printing device and may be configured to be able to print the analysis result.

Further, the control box 49 may also store information other than the abnormality detection result, and the portable personal computer 70 may perform analysis using such information. For example, it is conceivable to store the current detected by the flow detection circuit 62 as information, estimate the load from this detected current, analyze whether or not the load is overloaded, or use the estimated load as history for maintenance information. Be done.

The embodiments disclosed this time are examples in all respects and do not provide a basis for a limited interpretation. Therefore, the technical scope of the present invention is not construed solely by the above-described embodiments, but is defined based on the description of the claims. It also includes all changes within the meaning and scope of the claims.

A van (vehicle)
3 Loading platform 9 Vehicle handling device 10 Power supply control device 11 Loading and unloading platform 30 Electric motor 31 Contactor 32 FET (field effect transistor)
33 Relief valve 35 Power unit 36 Push button type remote control switch 37 Battery cord 39 Chassis ground cord 45 Battery 47 Fuse box 49 Control box (open / close control unit, abnormality determination unit, storage unit, output unit)
55 Main switch in cab 57 Push button type remote control switch 60 Shunt resistor 62 Flow detection circuit (detector)
70 Portable personal computer 491 CPU (open / close control unit, abnormality determination unit)
492 RAM (temporary storage)
493 ROM
494 Control signal output circuit 495 Control signal input circuit 496 USB interface (output section)

Claims (3)

A loading / unloading platform is provided on the loading platform so as to be able to move up and down by a vehicle handling device, and a power supply control device for the vehicle handling device that drives the vehicle handling device by supplying power to an electric motor from a battery mounted on the vehicle.
A power supply circuit through which the drive current from the battery flows when the electric motor is driven, and
A contactor that is placed in the power supply line and opens and closes the power supply line,
A field-effect transistor that is arranged in the power supply circuit and opens and closes the power supply circuit,
An opening / closing control unit that controls the opening / closing of the power feeding circuit by controlling the opening / closing of the contactor and the ON / OFF of the field effect transistor.
A detector that detects the current flowing through the power supply path and
An abnormality determination unit that determines the presence or absence of an abnormality in the vehicle cargo handling device based on the current detected by the detection unit, and an abnormality determination unit .
A storage unit that stores data in the open / close control unit and the abnormality determination unit,
It is equipped with an output unit that outputs the data in the storage unit to an external device.
The abnormality determination unit determines that the field effect transistor has an abnormality when the current flowing through the power feeding circuit is detected by the detection unit during the period when the contactor is closed and the field effect transistor is turned off. Has a configuration to judge
The power supply control device of the vehicle cargo handling device is characterized in that the storage unit stores the determination data that the abnormality determination unit determines as having an abnormality during the period, so that the output unit can output the determination data. .. A loading / unloading platform is provided on the loading platform so as to be able to move up and down by a vehicle handling device, and a power supply control device for the vehicle handling device that drives the vehicle handling device by supplying power to an electric motor from a battery mounted on the vehicle.
A power supply circuit through which the drive current from the battery flows when the electric motor is driven, and
A contactor that is placed in the power supply line and opens and closes the power supply line,
A field-effect transistor that is arranged in the power supply circuit and opens and closes the power supply circuit,
An opening / closing control unit that controls the opening / closing of the power feeding circuit by controlling the opening / closing of the contactor and the ON / OFF of the field effect transistor.
A detector that detects the current flowing through the power supply path and
It is provided with an abnormality determination unit that determines the presence or absence of an abnormality in the vehicle cargo handling device based on the current detected by the detection unit.
When starting power supply to the electric motor, the open / close control unit controls to turn on the field effect transistor after a predetermined time after closing the contactor, and also controls the field effect transistor to be turned on for a short time within the predetermined time. It controls to turn on the transistor.
The abnormality determination unit compares the current detected by the detection unit with the first threshold value when the field effect transistor is turned on for a short time, and when the detected current exceeds the first threshold value. Is a power supply control device for a vehicle cargo handling device, which is characterized in that it is determined that there is an abnormality. The power supply control device for the vehicle cargo handling device according to claim 2.
When the open / close control unit can continuously rotate the electric motor by continuously supplying power to the stopped electric motor for a certain period of time or longer, the open / close control unit performs the electric field for a short time shorter than the fixed time. Effect A power supply control device for a vehicle cargo handling device, which controls turning on a transistor.

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