JPH0993725A - Device for controlling traveling of battery car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for controlling traveling of battery car which can weaken the field of a traveling motor with a simple constitution. SOLUTION: The common contact 22a of the cargo contactor 22 of a main cargo circuit 9 is connected to a cargo transistor 23. The other contacts 22b and 22c of the contactors 22 are respectively connected to a cargo motor 21 and the connecting point P among the armature 12a of a drive motor 12 and forward and backward contactors 14 and 15. When a battery car is run at a high speed, the common contact 22a of the contactor 22 is connected to the contact 22c of the contactor 22 by means of a cargo running control circuit 10 and the transistor 23 is connected in parallel with the field winding 12b of the drive motor 12. The conducting rate of the transistor 23 reaches a value corresponding to the duty ratio of a chopper signal inputted to a base terminal of the transistor 23 and the weakened field current corresponding to the conducting rate flows to the drive motor 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a running controller for a battery vehicle, and more particularly to a running controller for weakening a running motor of a battery vehicle to increase a running speed.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 2, in a battery vehicle such as a battery-powered forklift, a traveling main circuit 51 for traveling the battery vehicle and a cargo handling main circuit 52 for carrying out a cargo handling operation are provided. Both circuits 51 and 52 are provided.
Is connected to the battery 53.

A traveling motor 54 is provided in the traveling main circuit 51. The traveling motor 54 is a direct-winding DC motor and includes an armature 54a and a field winding 54b. A forward contactor 55 and a backward contactor 56 are connected to the field winding 54b, and the direction of the field current flowing through the field winding 54b is changed based on the switching operation of the two contactors 55, 56 to drive the traveling motor 54 forward and backward. By rotating the battery, the battery car can move forward and backward. The traveling transistor 57 is connected in series to the traveling motor 54 and is driven and controlled based on a known chopper signal input to its base terminal.

A cargo handling motor 58 is provided in the cargo handling main circuit 52, and the cargo handling motor 58 has a cargo handling contactor 59.
It is connected to the positive side terminal of the battery 53 via the, and is also connected to the negative side terminal of the battery 53 via the cargo handling transistor 60. Then, the cargo handling contactor 59 is turned on (closed), and the cargo handling transistor 60 is turned on / off based on a known chopper signal input to its base terminal to rotate the cargo handling motor 58 to be illustrated. Do not carry out cargo handling operations such as raising and lowering forks.

Further, the traveling main circuit 51 is provided with a field weakening circuit 61. The field weakening circuit 61 is composed of a field weakening contactor 62 and a field weakening resistor 63 which are connected in series, and is connected in parallel to the field winding 54b of the traveling motor 54. The field weakening circuit 61 causes a part of the current flowing through the field winding 54b during high-speed traveling of the forklift to flow through the field weakening contactor 62 to the field weakening resistor 63, thereby allowing the field winding 54b to generate the field. Is to reduce the restraint force on the armature 54a and increase the traveling speed.

[0006]

However, in the above forklift, since the field weakening contactor 62 and the field weakening resistor 63 are required to increase the traveling speed, the number of parts of the traveling main circuit 51 is large. Therefore, there is a problem that the cost is increased.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a running control device for a battery vehicle capable of weakening the field of the running motor with a simple structure. .

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, a first aspect of the present invention is a direct-current winding type traveling motor which is rotationally driven by a direct-current power source, the traveling motor and a direct-current power source. And a traveling switching element for driving and controlling the traveling motor, a cargo handling motor that is rotationally driven by a DC power supply, and a cargo handling motor that is connected between the cargo handling motor and the DC power supply. A cargo handling switching element that is drive-controlled, and a connection means that connects the cargo handling switching element to the cargo handling motor during a cargo handling operation, and connects the cargo handling switching element to a field winding of the travel motor during high-speed traveling. The point is to have and.

According to a second aspect of the invention, in the cargo handling control device for a battery vehicle according to the first aspect, the connecting means is connected between the cargo handling motor and the cargo handling switching element, and A contactor having a contact point connected to the field winding of the cargo handling motor, a contact point connected to the traveling motor, and a common contact point that is switch-connected to both contacts, and a cargo task switch-connecting the contactor. The gist is that it is composed of a traveling control circuit.

Therefore, according to the invention described in claim 1,
The switching means for cargo handling is connected to the field winding of the traveling motor during high-speed traveling by the connecting means, and a part of the field current flowing through the field winding is passed through the switching element for cargo handling to weaken the field. Be magnetized.

According to the second aspect of the present invention, the contactor is connected to the position where the cargo handling switching element is connected to the cargo handling motor by the cargo handling traveling control circuit and the field winding of the traveling motor. Switched to position.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is embodied in a battery type forklift will be described below with reference to FIG.

As shown in FIG. 1, the forward / reverse switching lever 1 is provided in the driver's seat of a forklift (not shown).
The forward / reverse switching lever 1 is provided to set forward traveling or backward traveling of the forklift. The forward / reverse switching lever 1 is provided with a set position detection sensor 2 for detecting whether the forward / reverse switching lever 1 is in the forward position, the reverse position or the neutral position. Further, the forklift is provided with an accelerator pedal 3. Accelerator pedal 3
Is provided with an accelerator sensor 4 for detecting the depression amount of the accelerator pedal 3. Further, the forklift is provided with a cargo handling lever 5. The cargo handling lever 5 is provided with an operation amount detection sensor 6 for detecting the amount of operation of the cargo handling lever 5.

The forklift is also provided with a cargo handling control device 7. The cargo handling traveling control device 7 includes a traveling main circuit 8, a cargo handling main circuit 9, and a cargo handling control circuit 10. The traveling main circuit 8 and the cargo handling main circuit 9 are connected to a battery 11 as a DC power source. Although not shown, the cargo handling control circuit 10 is also connected to the battery 11.

The traveling main circuit 8 is provided with a traveling motor 12 as a traveling motor, and the traveling motor 12 is connected to the battery 11 via a regenerative contactor 13. The traveling motor 12 is a direct-winding DC motor, and the armature 1
2a and field winding 12b.

A forward contactor 14 and a backward contactor 15 as switching contactors are connected to the field winding 12b. Then, the direction of the magnetic field current flowing through the field winding 12b is changed by the complementary switching operation of both the contactors 14 and 15, and the traveling motor 12 is rotated forward and backward.

The traveling transistor 16 as a traveling switching element has its collector terminal at the forward contactor 1.
4 and the reverse contactor 15 and the emitter terminal is connected to the negative side terminal of the battery 11. Therefore, the traveling transistor 16 is connected in series to the traveling motor 12. The base terminal of the traveling transistor 16 is connected to the cargo handling traveling control circuit 10.

The flywheel diode 17 has its anode connected to the armature 12a and the forward and reverse contactors 14, 1
5 is connected to the connection point P between the
1 is connected to the positive terminal. The flywheel diode 18 has its anode connected between the forward and reverse contactors 14 and 15 and the running transistor 16,
The cathode is connected to the positive terminal of the battery 11.

A traveling current sensor 19 is connected between the traveling motor 12 and the regenerative contactor 13. The traveling current sensor 19 detects the drive current supplied from the battery 11 and outputs it to the cargo handling traveling control circuit 10.

The regenerative diode 20 has its anode connected to the negative terminal of the battery 11 and its cathode connected between the regenerative contactor 13 and the traveling current sensor 19.

The cargo handling main circuit 9 is provided with a cargo handling motor 21 as a cargo handling motor, and the cargo handling motor 21 is directly connected to the battery 11. The cargo handling motor 21 is a direct-winding DC motor, and includes an armature 21a and a field winding 21b. One end of the armature 21a is connected to the plus side terminal of the battery 11, and the other end of the armature 21a is connected to the field winding 2
It is connected to the cargo handling contactor 22 as a connecting means via 1b.

The cargo handling contactor 22 is provided with a common contact 22a and contacts 22b and 22c. Contact 22b,
22c is alternately connected to the common contact 22a.
The contact 22b is connected to the field winding 21b of the cargo handling motor 21, and the contact 22c is connected to a connection point P between the armature 12a of the traveling motor 12 and the forward / reverse contactors 14, 15.

The cargo handling transistor 23 as a cargo handling switching element has its collector terminal at the cargo handling contactor 2.
It is connected to the two common contacts 22a, and the emitter terminal is connected to the negative side terminal of the battery 11. Therefore, the cargo handling transistor 23 is connected in series to the cargo handling motor 21. The base terminal of the cargo handling transistor 23 is connected to the cargo handling control circuit 10.

The cargo handling contactor 22 and the cargo handling transistor 2
A cargo handling current sensor 24 is inserted between and connected to the No. 3 and No. 3. The flywheel diode 25 has its anode connected to the collector terminal of the cargo handling transistor 23 and its cathode connected to the positive terminal of the battery 11.

The cargo handling control circuit 10 includes the sensors 2,
It is connected to 4,6. The cargo handling traveling control circuit 10 receives a detection signal from the set position detection sensor 2, controls switching of the forward and backward contactors 14 and 15 based on the detection signal, and controls the field flowing in the field winding 12b of the traveling motor 12. Switch the direction of magnetic current. Further, the cargo handling traveling control circuit 10 inputs a detection signal from the accelerator sensor 4 and outputs a chopper signal having a duty ratio based on the detection signal to the base terminal of the traveling transistor 16. The running transistor 16 is on / off controlled by the chopper signal, and has a conduction rate according to the duty ratio of the chopper signal input to the base terminal. The current flowing through the traveling motor 12 is controlled by the conduction rate of the traveling transistor 16, and the traveling motor 12 rotates at a rotation speed according to the current.

Further, the cargo handling control circuit 10 receives a detection signal from the cargo handling lever 5 and outputs a chopper signal having a duty ratio based on the detection signal to the base terminal of the cargo handling transistor 23. The cargo handling transistor 23 is on / off controlled by a chopper signal, and has a conduction rate corresponding to the duty ratio of the chopper signal input to the base terminal. The current flowing through the cargo handling motor 21 is controlled by the conductivity of the cargo handling transistor 23, and the cargo handling motor 21 rotates at a rotation speed corresponding to the current.

Further, the cargo handling traveling control circuit 10 switches the cargo handling contactor 22 to the contact 22c side during high speed traveling. Then, the cargo handling transistor 23 is connected in parallel to the field winding 12b of the traveling motor 12. Further, the cargo handling traveling control circuit 10 outputs a chopper signal having a duty ratio based on the detection signal from the accelerator sensor 4 to the base terminal of the cargo handling transistor 23. Then, the cargo handling transistor 23 has a conduction rate according to the duty ratio of the chopper signal input to the base terminal, and a field weakening current according to the conduction rate flows.

The high-speed traveling means that the conduction ratio of the traveling transistor 16 controlled by the cargo handling traveling control circuit 10 according to the depression amount of the accelerator pedal 3 is 100%, that is, the traveling transistor 16 is always on. Is. In the present embodiment, the accelerator pedal 3 is set to run at a high speed when the accelerator pedal 3 is depressed by a predetermined amount of the depression amount of the accelerator pedal 3. That is, the cargo handling traveling control circuit 10 outputs a chopper signal to the traveling transistor 16 to control the on / off of the transistor 16 while the depression amount of the accelerator pedal 3 is up to a predetermined amount. When the depression amount of the accelerator pedal 3 exceeds a predetermined amount or more, the cargo handling traveling control circuit 10 controls the traveling transistor 16 to be always on, and connects the common contact of the cargo handling contactor 22 to the contact 22c so that the cargo handling transistor 23 is connected. On the other hand, a chopper signal is output to control ON / OFF of the transistor 23.

Next, the operation of the battery type forklift configured as described above will be described. Now, after operating the forward / reverse switching lever 1 to move forward or backward to drive the forklift, the accelerator pedal 3 is depressed. Then, the cargo handling traveling control circuit 10 causes the set position detection sensor 2 to
The operation direction of the forward / reverse switching lever 1 is detected via the forward and backward contactor 1 according to the detected operation direction.
4, 15 are switched and controlled. Also, the cargo handling control circuit 1
0 outputs a chopper signal having a duty ratio corresponding to the depression amount of the accelerator pedal 3 detected via the accelerator sensor 4 to the traveling transistor 16. Then, the traveling transistor 16 has a conduction ratio corresponding to the duty ratio of the chopper signal, that is, the depression amount of the accelerator pedal 3, and a field current corresponding to the conduction ratio flows to the field winding 12b, so that the traveling motor 12 is positive. The forklift runs by turning or reversing. At this time, the cargo handling contactor 22 has its common contact 22
a and the contact 22b are connected. Therefore, the cargo handling operation can be performed by operating the cargo handling lever 5 and controlling the rotation of the cargo handling motor 21 according to the operation amount.

Next, when the accelerator pedal 3 is depressed by a predetermined amount or more, the cargo handling traveling control circuit 10 causes the traveling transistor 16 to travel.
Is always turned on to make its conductivity 100%. Further, the cargo handling traveling control circuit 10 switches and connects the common contact 22a of the cargo handling contactor 22 and the contact 22c, and
The cargo handling transistor 23 is on / off controlled by a chopper signal having a duty ratio corresponding to the depression amount of the accelerator pedal 3. Then, the field winding 12b of the traveling motor 12
The field current flowing in the field winding 1 is reduced by the weakening field current flowing through the cargo handling transistor 23.
The field due to 2b is reduced. As a result, the armature 12a
Since the restraint force is reduced, the rotation speed of the traveling motor 12 increases and the traveling speed of the forklift increases.

Further, the cargo handling transistor 23 is on / off controlled by a chopper signal having a duty ratio corresponding to the depression amount of the accelerator pedal 3. Then, the conductivity of the cargo handling transistor 23 changes according to the depression amount of the accelerator pedal 3, and a field weakening current corresponding to the conductivity of the transistor 23 flows. As a result, a field current reduced according to the conductivity of the cargo handling transistor 23 flows through the field winding 12b, and the field changes. Therefore, during high-speed traveling, the rotation speed of the traveling motor 12, that is, the forklift. The traveling speed of can be finely controlled.

As described above, according to this embodiment, the following actions and effects can be obtained. (1) A cargo handling contactor 22 having contacts 22b and 22c that are switched and connected to the common contact 22a is connected between the cargo handling motor 21 and the cargo handling transistor 23, and the contact 2
2c is connected to a connection point P between the armature 12a of the traveling motor 12 and the forward / reverse contactors 14, 15. Then, when traveling at high speed, the common contact 22 of the cargo handling contactor 22.
In addition to connecting a and the contact 22c, a chopper signal having a duty ratio corresponding to the amount of depression of the accelerator pedal 3 is output to the base terminal of the cargo handling transistor 23 so that a field weakening current flows through the transistor 23. as a result,
Since the conventional field weakening resistor 63 is unnecessary, the number of parts can be reduced and the configuration can be simplified.

(2) By controlling the cargo handling transistor 23 to change the conductivity of the transistor 23, the field weakening current flowing in the transistor 23 can be continuously varied, and accordingly, the traveling motor 12 correspondingly. The field current flowing through the field winding 12b can be continuously changed. As a result, the rotational speed of the traveling motor 12, that is, the traveling speed of the forklift can be finely controlled even during high-speed traveling.

The present invention is not limited to the above-mentioned embodiment, and may be carried out as follows without departing from the spirit of the present invention. (1) In the above embodiment, the cargo handling current sensor 24 may be provided at any position as long as it can detect the current flowing through the cargo handling motor 21, for example, the cargo handling motor 2
1 may be provided between the cargo handling contactor 22 and the like.

(2) In the above embodiment, a resistor may be inserted and connected between the contact point 22c of the cargo handling contactor 22 and the connection point P. (3) In the above embodiment, the cargo handling contactor 22 having the contact point 22b connected to the cargo handling motor 21 and the contact point 22c connected to the traveling motor 12 is used, but the conventional cargo handling contactor 59 shown in FIG. 2 is used. 21 is connected between the cargo handling transistor 23 and the conventional field weakening contactor 6
2 is connected between the cargo handling transistor 23 and the connection point P. Then, when traveling at a high speed, the cargo handling contactor 59 is controlled to be off and the field weakening contactor 62 is controlled to be on. With this configuration, the number of parts can be reduced by the amount corresponding to the conventional field weakening resistance 63, and the conduction rate of the cargo handling transistor 23 can be continuously changed to finely control the traveling speed of the forklift.

(4) The present invention is not limited to the forward / reverse switching lever 1, the accelerator pedal 3, and the cargo handling lever 5 in the above-described embodiment, and may be, for example, a toggle-type forward / backward switch, an accelerator lever, or a toggle-type cargo handling switch. Good.

(5) In the above-described embodiment, the field weakening control may be performed only when moving forward or only when moving backward. (6) In the above embodiment, the forklift is embodied, but it may be embodied in another electric industrial vehicle.

(7) In the above embodiment, the case where the traveling motor and the cargo handling motor are driven is embodied. However, the embodiment is embodied when other motors including a series-wound DC motor are chopper-controlled. You may carry out.

(8) In the above embodiment, the traveling switching element and the cargo handling switching element are not particularly limited as long as they have a switching function.
You may implement using SIT and SIT.

[0040]

As described above in detail, according to the present invention, it is possible to provide a traveling control device for a battery vehicle capable of performing the field weakening of the traveling motor with a simple structure.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a travel control device for a battery vehicle that embodies the present invention.

FIG. 2 is a circuit diagram of a travel control device for a conventional battery vehicle.

[Explanation of symbols]

10 ... Cargo handling traveling control circuit as connecting means, 11 ... Battery as DC power source, 12 ... Traveling motor as traveling motor, 12a ... Armature, 12b ... Field winding, 16 ...
A traveling transistor as a traveling switching element, 2
2 ... a cargo handling contactor as a connecting means, 22a ... a common contact, 22b, 22c ... a contact, 23 ... a cargo handling transistor as a cargo handling switching element.

Claims (2)

[Claims] 1. A direct-current winding type traveling motor that is rotationally driven by a DC power source; a traveling switching element that is connected between the traveling motor and the DC power source and that drives and controls the traveling motor; A cargo handling motor that is driven to rotate by a power supply, a cargo handling switching element that is connected between the cargo handling motor and a DC power source, and drives and controls the cargo handling motor, and the cargo handling switching element is used during the cargo handling operation. A traveling control device for a battery vehicle, comprising: a connecting means that is connected to a motor and that connects the cargo handling switching element to a field winding of the traveling motor during high-speed traveling. 2. The connection means is connected between the cargo handling motor and the cargo handling switching element, and is connected to a contact that is connected to a field winding of the cargo handling motor and to the traveling motor. The traveling control device for a battery vehicle according to claim 1, comprising a contactor having a contact point and a common contact point that is switched and connected to both contacts, and a cargo handling traveling control circuit that switches and connects the contactor.