JPH0767205B2 - Battery car controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a control device for a battery vehicle.

(Prior Art) The traveling operation and cargo handling operation of an industrial vehicle such as a battery-powered forklift are controlled by a traveling control circuit 71 and a cargo handling control circuit 72, respectively, as shown in FIG. Then, when the battery 73 is over-discharged, the relay 75 is actuated and excited by a signal from the battery capacity meter 74 to open the cargo handling contactor 76, the cargo handling control circuit 71 is cut off and the cargo handling operation is forcibly stopped, and the battery 73 is discharged. Will be protected.

(Problems to be Solved by the Invention) However, since the cargo handling control circuit 71 described above is configured to be turned on / off by the manual changeover switch 77, the manual switch 77 of the manual switch 77 is not activated during overdischarge. When the cargo handling control circuit 71 cut off by the operation is re-energized to perform the cargo handling work, a large current flows through the battery 73, and the battery 73
Will be consumed significantly and shorten the service life.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a battery vehicle control device capable of protecting the battery without imposing an excessive load on the battery during overdischarge.

Configuration of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention is to drive the vehicle based on the operation of the travel operation means, and a travel drive means that uses a battery as a drive power source. , The cargo handling mechanism provided in the vehicle is operated based on the operation of the cargo handling operating means, and the battery operating state is determined based on the battery residual capacity detected by the battery voltage detector and the battery handling power source. When the detection means for detecting the discharge and the detection means detect the over-discharge, for the simultaneous operation of the traveling operation means and the cargo handling operation means, only the operation of the traveling operation means is effective,
First control means for operating the traveling drive means and drive control of the cargo handling drive means such that the cargo handling operation speed becomes slower than usual when the detection means detects over-discharge and only the cargo handling operation means is operated. The gist of the present invention is that the second control means for

(Operation) By adopting the above-mentioned means, when the battery discharging is detected by the detecting means, only the traveling drive means is operated when the cargo handling operating means and the cargo handling operating means are simultaneously operated. The vehicle can be moved. as a result,
By simultaneously performing the traveling operation and the cargo handling operation in the over-discharged state, it is possible to prevent a large current from flowing, and it is possible to move the vehicle to a place where the battery is replaced or charged. Further, when the detection means detects the over-discharge and only the cargo handling operation means is operated, the cargo handling mechanism operates, but the cargo handling operation speed becomes slower than usual. As a result, the operator can continue the minimum cargo handling operation in the overdischarged state without performing any special operation, and the worker can easily grasp the overdischarged state of the battery by the change in the cargo handling operation speed. be able to.

(Embodiment) An embodiment of the present invention embodied in a control device for a battery-powered forklift will be described in detail below with reference to the drawings.

A forklift vehicle 1 shown in FIG. 3 travels forward and backward by forward and reverse rotations of drive wheels 2 provided at a rear portion thereof, and further includes a mast 4 provided at a front portion and a fork 3 supported thereby. 5, the cargo handling operation is performed. The cargo handling mechanism 5 is driven by the lifting and lowering operations of a lift cylinder L, a tilt cylinder, and a reach cylinder (none of which is shown), of which the reach cylinder moves the mast 4 along a guide portion 6 extending forward of the vehicle 1. Move back and forth. The lift cylinder L raises and lowers the fork 3 along the mast 4, and the tilt cylinder tilts the fork 3.

FIG. 2 shows a drive system electric circuit of a forklift. Of the main cargo handling circuits P, the cargo handling motor 7 is connected to the positive terminal of the battery 8 via a cargo handling connector 8a. The loading motor 7 is an armature 9
And the field winding 10 and the field winding 10
Is connected to the negative terminal of the battery 8 through the cargo handling transistor 11 for controlling the chopper and the current sensor 12. Then, by holding the cargo handling connector 8a in the illustrated ON state and controlling the cargo handling transistor 11 to be turned on and off, the rotation speed of the cargo handling motor 7 is controlled.

Next, the traveling main circuit M will be described. Motor for traveling
13 is connected to the plus terminal of the battery 8 via a current sensor 14 and a regenerative contactor 15. As the traveling motor 13, a series winding motor including an armature 16 and a field winding 17 is adopted, and a forward contactor 18 and a reverse contactor 19 are connected to both ends of the same field winding 17, respectively. A bypass contactor 20 and a main transistor 22 are connected in parallel between the contactors 18, 19 and the battery 8. Then, as shown in the figure, the regenerative contactor 15 is turned on, both contactors 18 and 19 are held at the forward movement position, and the traveling motor 13 is rotated in the forward direction to advance the vehicle 1. ing. At this time, the rotation speed of the traveling motor 13 is increased or decreased by the chopper control of the main transistor 22, so that the traveling speed of the vehicle 1 is adjusted.

A regeneration transistor 23 and a regeneration resistor are provided between the armature 16 of the traveling motor 13 and the positive terminal of the battery 8.
23a is connected in series. Further, flywheel diodes 24 and 25 are connected between the forward and backward contactors 18 and 19 of the field winding 17 of the traveling motor 13 and the positive terminal of the battery 8, respectively, for further regeneration. A regenerative diode 26 is also connected between the contactor 15 and the negative terminal of the battery 8.

Subsequently, a control configuration of the traveling main circuit M and the cargo handling main circuit P described above will be described with reference to FIG.

The central processing unit (hereinafter referred to as CPU) 27 as the detection means, the first control means and the second control means has a read-only memory (R
OM) 28 and a readable / writable memory (RAM) 29 are connected. The ROM 28 stores a control program for the CPU 27, and the RAM 29 temporarily stores digital data corresponding to analog data input from various input members.

The connection configuration of the input side of the CPU 27 will be described. The traveling accelerator sensor 30 and the cargo handling sensor 30 that are turned on and off by the stepping operation of the travel accelerator and the cargo handling accelerator, respectively, and increase and decrease the rotational speeds of the travel motor 13 and the cargo handling motor 7. Accelerator sensor 31 is connected via A / D converters 32 and 33, respectively. Further, the current sensors 12 and 14 of both main circuits M and P are connected via the A / D converter 34, respectively, and their analog output values are digitally converted and input to the CPU 27. Further, the CPU 27 is connected with forward and reverse limit switches 35a and 35b, which are selectively switched by operating the direction lever and indicate the traveling direction of the vehicle 1. The CPU27 has a lift lever,
A lift limit switch 36a, a reach limit switch 36b, and a tilt limit switch 36c, which are turned on / off by operating the reach lever and the tilt lever, are connected. By turning these switch groups 36a, 36b, 36c on and off, the valves of the cargo handling pump controlled by the cargo handling motor 7 are switched, and hydraulic oil is supplied to and discharged from the corresponding cylinders. There is.

The traveling accelerator sensor 30, the forward and backward limit switches 35a and 35b constitute traveling operation means, and further the cargo handling accelerator 31, the lift switch 36a,
The tilt switch 36b and the reach switch 36c constitute cargo handling operation means.

A battery voltage detector 37 that detects the voltage of the battery 8 is connected to the CPU 27.
Based on the battery voltage output from the CPU 27, the CPU 27 calculates the remaining capacity of the battery 8 and outputs the remaining capacity data one by one.
Write to RAM29. Further, a key switch 38 is connected to the CPU 27, and when the key switch 38 is turned on, control of both main circuits M and P is started.

Further, contactor drive circuits 40 to 44 are respectively connected to the output side of the CPU 27, and open / close control of the cargo handling contactor 8a, the regenerative contactor 15, the forward contactor 18, the reverse contactor 19, and the bypass contactor 20. Further, the cargo handling transistor 11, the traveling transistor 22, and the regeneration transistor 23 are connected to the CPU 27 through three transistor driving circuits 45 to 47, respectively, and the transistors 11, 22, 23 are connected.
ON / OFF control. These members connected to the output side are driven according to the programs stored in the ROM 28 in accordance with the operation of the members on the input side.

That is, for example, the cargo handling contactor 8a is provided with the lift switch 36
It is turned on / off by relay control of the contactor drive circuit 44 associated with the on / off operation of a, and the cargo-handling transistor 11 is turned on / off by the operation of the cargo-handling accelerator sensor 31. Detected at. Further, the regenerative contactor 15 has a forward or reverse switch 35a,
It is turned on / off by the control of the contactor drive circuit 40 associated with the operation of 35b.

Further, the forward contactor 18 and the reverse contactor 19 are switched from the forward position to the reverse position by switching the forward / backward and reverse switches 35a and 35b, respectively.

The traveling transistor 22 is driven by the transistor driving circuit 45 by the operation of the traveling accelerator 30, and the change in the current flowing through the traveling motor 13 when it is turned on is detected by the current sensor 14. Further, the bypass contactor 20 is driven by the contactor drive circuit in accordance with the operation of the traveling accelerator 30, and the current sensor 21 detects the current flowing in the ON state.

Further, a battery capacity meter 49 is connected to the output side of the CPU 27 via a display drive circuit 48. As shown in FIG. 4, this battery capacity meter 49 has one check lamp 50.
And six first to sixth indicator lamps 51 to 56 as six light emitting portions arranged side by side, and one battery lamp 57 provided at the bottom. These lamps 50, 51-56,
57 is formed of a light emitting diode, emits light in yellow, green, and red, respectively, and by turning on the key switch 38, all the lamps 50, 51 to 56, 57 are lit for several seconds,
It has been confirmed that the lamp will not burn out.
The battery capacity meter 49 calculates the decrease in the remaining capacity of the battery 8 calculated by the CPU 27 based on the output of the battery voltage detector 37 from the F side (no discharge) of the first to sixth indicator lamps 51 to 56 to the E side ( It is digitally displayed by extinguishing one by one to all discharge side). When the discharge amount of the battery 8 exceeds a preset allowable value, the battery lamp
57 lights up and a warning is displayed. The battery 8 is
When the discharge reaches 100% or more, that is, the over-discharge state, all the indicator lamps 51 to 56 of the capacity meter 49 are turned off as shown in FIG.

Now, the overdischarge prevention function of the control device configured as described above will be described below.

When the capacity of the battery 8 is discharged 100% or more and falls below a predetermined value during the loading of the vehicle 1, the CPU 27 uses the transistor driving circuit 46 for loading based on the signal input from the battery voltage detector 37. The on / off control of the transistor 11 is switched to the overdischarge mode. In accordance therewith, the current supplied from the battery 8 to the cargo handling motor 7 is reduced, and the cargo handling operation of the vehicle 1 is forcibly delayed. As a result, the driver recognizes that the over-discharge operation has been performed.

After that, when the switches corresponding to these are turned on by the simultaneous operation of the traveling and cargo handling levers, the CPU 27 prohibits both contactor drive circuits 40, 44 from operating at the same time, and only one contactor drive circuit 40 operates. A command is issued, the regenerative contactor 15 is switched to the ON position, and the traveling main circuit M is preferentially energized. Therefore, although the traveling motor 13 is rotationally driven and the vehicle 1 can be moved to the external charging device, the cargo handling motor 7 is held in a stopped state and a large current is prevented from flowing.

When only one of the traveling system operation and the cargo handling system operation is performed after the above-described forced operation of the vehicle 1, the CPU 27 causes the contactor drive circuits 40 and 44 to regenerate or load the contactor 1.
Turn on 5,8a. Therefore, the stopped cargo handling operation is not discharged in the middle of its execution, and the minimum necessary work can be continued.

As described above, when the battery 8 is used in over discharge,
Simultaneous operation of the traveling and cargo handling main circuits M and P is prohibited, and subsequent discharges are suppressed to call attention to the driver. After that, the traveling main circuit M is energized, and the vehicle 1 is moved to the external charging device. Therefore, after over-discharging, the traveling is continued due to the driver's carelessness, the cargo handling operation is avoided, and only the minimum current required for the vehicle 1 to move to the external charging device is supplied to the traveling main circuit M. Therefore, there is no fear that the battery 8 will be consumed early due to excessive load.

Effects of the Invention As described in detail above, according to the present invention, it is possible to prevent a large current from flowing by simultaneously performing the traveling operation and the cargo handling operation in the overdischarge state, and to protect the battery, The vehicle can be moved to a place where the battery is replaced or charged. In addition, the operator can continue the minimum necessary cargo handling operation while protecting the battery in the over-discharged state without performing any special operation, and the operator can change the cargo-loaded operation speed depending on the over-discharged state of the battery. It has the excellent effect that it can be grasped more easily.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electric control configuration of the present invention,
FIG. 2 is an electric circuit diagram showing a main circuit for traveling and cargo handling,
3 is a side view showing a forklift, FIG. 4 is a front view showing a battery capacity indicator, FIG. 5 is a front view showing a battery capacity indicator displaying 100% discharge, and FIG. 6 is a conventional technique. It is a circuit diagram. Vehicle 1, battery 8, detection means, first control means and second
CPU 27 as control means, travel accelerator sensor 30 as travel operation means, forward limit switch 35a and reverse limit switch 35b, cargo handling accelerator sensor 31 as cargo handling operation means, lift switch 36a, tilt switch 36b and reach. A switch 36c, a battery voltage detector 37, a traveling main circuit M as traveling drive means, and a cargo handling main circuit P as cargo handling driving means.

Claims (1)

[Claims] 1. A traveling drive means (M) for traveling a vehicle (1) based on an operation of traveling operation means (30, 35a, 35b) and using a battery (8) as a drive power source, and a cargo handling operation means ( 31,36a, 36b, 36c), the cargo handling mechanism provided in the vehicle (1) is operated based on the operation of the vehicle (1), and the cargo handling drive means (P) that uses the battery (8) as a driving power source, and the battery voltage detector ( Detecting means (27) for detecting over-discharge of the battery (8) based on the battery remaining capacity detected in (37), and the traveling operation means (30) when the detecting means (27) detects over-discharge. , 35a, 35b) and cargo handling operation means (31,36a, 36b, 36
For simultaneous operation with c), traveling operation means (30, 35a, 35b)
The first control means (27) for activating the traveling drive means (M) and the detection means (27) detect over-discharge, and the cargo handling operation means (31, 36a, 36b, 36c) A) a second control means (27) for driving and controlling the cargo handling drive means (P) so that the cargo handling operation speed becomes slower than usual when only one is operated.