JP2001198163A - Hand-push control system of motor car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cancel braking force and permit hand-push travel on actuation of a hand-push switch, and ensure safety in the hand-push travel at the same time, in motor car of a type where an electromagnetic brake, or the like, applies braking force for stopping. SOLUTION: This hand-push control system of a motor car comprises motor controlling means for controlling driving and dynamic braking of a wheel driving motor 1, electromagnetic brake controlling means for applying an electromagnetic brake 2 to brake and stop the rotation of the motor 1 for a stopping operation, hand-push mode selecting means for releasing the electromagnetic brake 2 and switching the motor 1 to a dynamic braking condition upon actuation of a hand-push switch 3, forward/reverse travel selecting means for detecting the direction of rotation of the motor 1 in the hand-push mode and switching a forward and a reverse changeover relays 4 and 5 in the direction same as the direction of rotation of the motor 1, and dynamic braking canceling means for detecting the rotation of the motor 1 likewise in the hand-push mode and reducing or canceling the dynamic braking force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle such as an electric wheelchair, and more particularly to a control device for manually pushing the electric vehicle without using power.

[0002]

2. Description of the Related Art In an electric vehicle of this type, particularly an electric wheelchair, in order to facilitate a driving operation, an accelerator for controlling a traveling speed is operated to a neutral position, that is,
In conjunction with the stop operation, the motor drive circuit is switched to a closed circuit to perform power generation braking, and a braking means such as activating an electromagnetic brake attached to the motor shaft is operated, and other manual brakes are operated even on a slope. It can be stopped without any trouble. For this reason, a clutch is provided at the end of the transmission path of the gear box that drives the wheels to enable manual driving when stored in a narrow garage, etc., so that the transmission relationship with the motor and electromagnetic brake is cut off and the wheels can rotate freely. There are technologies to configure. In this technology, when the clutch is disengaged and the vehicle is manually pushed on a downhill or the like, acceleration due to gravity may be applied, which may be dangerous. For this reason, the applicant of the present application
No. 255402, the above-mentioned braking force of the dynamic braking and the electromagnetic brake is released by the operation of a hand-operated switch to enable manual pushing, and when the detected value of the hand-held traveling speed exceeds a certain value, the dynamic braking and the electromagnetic brake are operated again. We have proposed a technology that regulates the speed and enables safe manual driving.

[0003]

In the above technique, when the hand switch is operated, all of the electromagnetic brake and the power generation braking are released or released. Therefore, on a slope, only the hand switch is operated and the hand push is performed by the gravitational acceleration. There is a danger that the vehicle will travel in a downward slope direction irrespective of the direction in which it is to be attempted. The present invention seeks to remedy such drawbacks.

[0004]

A motor control means for controlling the driving of the wheel driving motor 1 and the electric power generation braking, and an electromagnetic brake control means for applying the electromagnetic brake 2 to stop the rotation of the motor 1 during the stop operation. When the hand switch 3 is turned on, the electromagnetic brake 2 is released and the motor 1 is turned on.
And a forward / reverse switching means for detecting the rotation direction of the motor 1 in the manual pushing mode and switching the forward / backward switching relays 4 and 5 in the same direction as the rotation direction of the motor 1. Motor 1 in manual push mode
And a power generation braking release means for reducing or releasing the power generation braking force by detecting the rotation of the electric vehicle.

[0005]

Operation and effect of the present invention In the case of normal running, a speed command is issued by operating the accelerator lever as in the prior art,
The motor control means controls the driving of the motor 1 and the power generation braking, and travels at the command speed. In the case of performing hand-traveling without using power, such as turning in a narrow passage or entering a garage, when the hand-operating switch 3 is operated to switch to the manual-push mode,
The electromagnetic brake 2 is released, and the motor 1 is brought into the power generation braking state. Next, when manual driving starts, the motor 1
, The forward / reverse switching relays 4 and 5 are switched to the same direction as the rotation direction of the motor 1 and the rotation of the motor 1 is also detected to reduce or cancel the power generation braking force. Accordingly, when the manual driving is started, the braking force is reduced or released with this operation, so that the manual driving can be smoothly performed with a light force. Further, as described above, when switching to the manual pushing mode, the motor 1 maintains the power generation braking state while the manual pushing operation is not performed. By doing so, it is possible to provide resistance to the self-weight running in the downward slope direction, and it is safer.

[0006]

1 is a block diagram showing the connection between input means and control means. FIG. 1 is a block diagram showing a connection state of input means and control means.
U and 7 are key switches, which are configured to be able to supply the current of the battery power supply to the control circuit and the drive circuit by connecting the key switch 7. Reference numeral 8 denotes a speed command signal generator, which is specifically constituted by a variable resistor that is rotationally adjusted by an accelerator lever, and outputs an output voltage of the variable resistor to a CPU.
Input to 6. Note that the output voltage of the speed command signal generator 8 at the neutral corresponding position that is automatically reset when the accelerator lever is released is set to the stop command voltage. Reference numeral 9 denotes a forward / reverse changeover switch. By operating the switch 9, the forward relay 4 or the reverse relay 5 can be connected via the forward relay switch 10 or the reverse relay switch 11 to control the rotation direction of the motor 1. It is configured in. Reference numeral 12 denotes a main relay switch, which is excited by a power-on operation of the key switch 7 to connect the main relay 13 to enable supply of battery current to the drive circuit.

Reference numeral 14 denotes a drive transistor, the gate side of which is connected to a motor drive circuit 15. The CPU 14 calculates a command speed of the speed command signal generator 8 and an actual speed detected by a motor rotation sensor 17 described later. The operation is controlled by a drive pulse output from the CPU 6, and the motor 1 is supplied with a current and driven. Reference numeral 16 denotes a braking transistor, which is likewise a motor drive circuit 15.
The gate side is connected to the motor 1 and is controlled by a braking pulse output from the CPU 6 to give the motor 1 a power generation braking action. Further, the transistors 14 and 16 are connected in series, and diodes 14a and 16a which operate at the time of reverse bias are incorporated therein. The drain side of the driving transistor 14 is connected to the +24 V power supply side, and the source side of the braking transistor 16 is connected to the ground side. The motor rotation sensor 17 is formed of a tacho-dyne attached to the motor shaft, and is configured to detect the number of rotations and the rotation direction of the motor 1 by detecting rotation pulse outputs at two locations around the motor shaft. Numeral 2 denotes an electromagnetic brake of negative operation, which is configured to release braking by energization during traveling and to return by spring force to apply a braking force to the motor shaft during stopping. Reference numerals 18 and 19 are transistors for two-stage amplification of the electromagnetic brake. 20 is a current detection circuit, 21 is a 5-row LED
A battery meter consisting of: a motor temperature sensor 22;
23 is a control circuit temperature sensor, and 24 is an outside air temperature sensor.

Reference numeral 3 denotes a hand switch, which can be switched to the hand pressing mode only when the hand pressing switch 3 is turned on after the key switch 7 is turned on and before the accelerator operation. Next, the operation will be described. In the case of normal traveling, when the accelerator operation is performed after the key switch 7 is turned on, the electromagnetic brake 2 is released, and the speed command signal generator 8 is controlled in accordance with the operation amount. A command voltage is input to the CPU 6, a drive pulse and a braking pulse are output from the CPU 6 in accordance with the command value, the drive transistor 14 is driven by the drive pulse, and the vehicle runs by applying a battery current to the motor 1. At the same time, the value detected by the motor rotation sensor 17 is input to the CPU 6 to calculate the actual traveling speed and compare it with the commanded speed. Perform feedback control. If the actual speed is higher than the commanded speed, a braking pulse is output from the CPU 6 in accordance with the speed difference to drive the braking transistor 16 to suppress the speed by dynamic braking.

[0009] When the vehicle is stopped, releasing the hand from the accelerator lever automatically returns to the neutral position by the elastic force.
A stop voltage is output from the speed command signal generator 8, and a slow stop control means for gradually reducing the drive pulse and increasing the brake pulse is output from the CPU 6 based on this command, so that the electric vehicle is gradually decelerated. At the same time, the power supply to the electromagnetic brake 2 is cut off after a predetermined time from the output of the stop command voltage, a braking force is applied to the motor shaft, and the electric vehicle is reliably stopped.

Next, the operation using the hand switch 3 will be described with reference to the flowchart shown in FIG. When the accelerator operation is performed first after the key switch 7 is turned on, the above-described normal traveling mode is set. When the hand switch 3 is operated first after the key switch 7 is turned on, the mode is switched to the manual driving mode. When the mode is switched to the manual driving mode, first, the CPU 6 outputs a braking pulse of 100% motor braking ratio (B) to drive the braking transistor 16 to the power braking state. After that, the hand switch 3 is continuously pressed. If so, the electromagnetic brake 2 is released.

Next, when the operator starts hand pushing and the motor 1 starts rotating, the motor rotation sensor 17 detects the number of rotations and the rotation direction of the motor 1 and inputs them to the CPU 6. Mdir) is compared with the relay setting direction (Rdir) of the forward / reverse switching relays 4 and 5 which are set, and if they are the same direction, the manual push constant speed control is performed. That is, the traveling speed by the motor rotation sensor 17 by manual pushing is 2 km / h.
In the above case, the braking pulse is increased to increase the motor power braking rate (B). If the traveling speed is equal to or less than 1.8 km / h, the braking pulse is reduced to reduce the motor power braking rate (B). Decrease and control to a safe hand pushing speed. Also, at the start of manual pushing, the rotation direction of the motor 1 (Mdi
r) and the setting direction (Rdir) of the relays 4 and 5 are opposite, if the hand pushing speed at this time is 0.3 km / h or less, the motor power generation braking rate (B) is set to 100%, and After switching the relay setting direction (Rdir) to the same direction as the motor rotation direction (Mdir) in a decelerated state, the above-described manual push constant speed control is performed.

The setting direction (Rdir) of the relays 4 and 5
, The motor 1 cannot be closed, and the forward and backward sides can be manually pushed by the same light operating force. The same applies when the hand pushing direction is switched halfway. When the above-mentioned hand pushing speed is 0.3 km / h or more, the braking pulse is increased to increase the motor power generation braking rate (B), and the hand pushing speed is reduced to 0.3 km / h or less. The setting direction (Rdir) is switched. Therefore, relays 4 and 5
And the contact load of the relay can be reduced, and troubles such as relay welding can be prevented. As described above, when the hand switch 3 is turned on and the electromagnetic brake 2 is released, the power generation braking rate (B) = 100
Since the braking pulse of% is output and a braking force is applied, resistance can be given to the running of the body by its own weight even on a slope or the like, which is safer. At the start of the manual pushing operation, the braking force causes the driver to feel slightly heavy, but when the motor rotation sensor 17 detects the traveling due to the manual pushing, the power generation braking rate (B) is quickly reduced, so that the manual pushing traveling can be performed with a light operation without feeling uncomfortable. .

If the vehicle speed is not detected continuously for three seconds or more even though the hand switch 3 is operated, it is determined that the operation is different from the normal hand pressing operation. Since the erroneous operation of the hand switch 3 can be considered, the electromagnetic brake 2 is actuated, and if the release operation of the hand switch 3 is performed in this state, the process returns to the flowchart. When it is turned off, the actual speed is detected by the motor rotation sensor 17, and when the speed is approximately 0 km / h, the braking pulse is increased to increase the power generation braking rate (B) by 100.
% And the electromagnetic brake 2 is actuated to stop the aircraft and enter a standby state. If a predetermined speed is detected at this time, braking is performed to increase the braking pulse and reduce the speed to approximately 0 km / h.
If one second has passed since then, a forced stop operation is performed. In the above embodiment, a braking pulse of 100% of the motor braking ratio (B) is output at the time of switching the manual pushing mode. However, an abnormal current or the like flowing through the motor drive circuit is detected within a range that does not significantly impair the braking force. The same effect can be obtained even if a predetermined number of neutral pulses are provided.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control circuit.

FIG. 2 is a flowchart.

[Explanation of symbols]

 1 Motor 2 Electromagnetic brake 3 Hand switch 4 Forward switching relay 5 Reverse switching relay

Claims (1)

[Claims] 1. A motor control means for controlling the driving of a wheel driving motor (1) and a power generation braking, and an electromagnetic brake control for stopping the rotation of the motor (1) by applying an electromagnetic brake (2) at a stop operation. Means, hand pressing mode switching means for releasing the electromagnetic brake (2) by turning on the hand pressing switch (3) and switching the motor (1) to the power generation braking state, and detecting the rotation direction of the motor (1) in the hand pressing mode. Forward / backward switching means for switching the forward / backward switching relays (4) and (5) in the same direction as the rotation direction of the motor (1); A hand-held control device for an electric vehicle, comprising a power generation braking release means for reducing or releasing the power generation braking.