JP3412640B2 - Control device for eddy current type reduction gear - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an eddy current type reduction device using a magnet for assisting a friction brake of a large vehicle. 2. Description of the Related Art An eddy current type speed reducer rotates when a magnet support wheel having a large number of electromagnets or permanent magnets is inserted into a brake drum connected to an output shaft or a propulsion shaft of a transmission. When the braking drum crosses the magnetic field, an eddy current is generated inside the braking drum and receives a braking torque. The eddy current type speed reducer according to Japanese Patent Application No. 4-137938 is provided with a pneumatic actuator that uses pressurized air in an air tank for an air brake in order to push a magnet support wheel into a brake drum. Can be The operating condition of the eddy current type reduction gear is when the retarder switch is closed and the clutch pedal and the accelerator pedal are respectively released. [0004] However, under the above-mentioned operating conditions, the eddy current type speed reducer may be held at the braking position even after the vehicle stops. In this case, it is necessary to return the eddy current speed reducer to the non-braking position before starting the vehicle.However, when the air pressure in the air tank is low or the ambient temperature is extremely low, the lubricating oil works. Unfortunately, if the pneumatic actuator lacks smooth operation, the eddy current speed reducer will not completely return to the non-braking position, and the braking action of the eddy current speed reducer will act on the propulsion shaft, and the vehicle will start smoothly. May be hindered. SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide an eddy current type speed reducer which automatically returns to a non-braking position immediately before or immediately after stopping. An object of the present invention is to provide a control device for a current-type reduction gear. In order to achieve the above object, according to the present invention, a magnet support wheel applies a magnetic field by an actuator to a rotary brake connected to an output shaft of a transmission of a vehicle. In an eddy current type speed reducer driven to be switched between a braking position to be applied and a non-braking position not to apply a magnetic field, a vehicle speed is predetermined when an accelerator pedal and a clutch pedal are in a release position in an energizing circuit of an electromagnetic switching valve for controlling an actuator. A release switch for switching the actuator to the non-braking position when the value is less than the value is inserted and connected. [0007] Even if the retarder switch is closed, the accelerator pedal and the clutch pedal are released to stop the vehicle, and when the vehicle speed falls below a predetermined value, the energizing circuit of the electromagnetic switching valve opens, and the actuator becomes eddy current decelerated. Serves to return the device to the non-braking position. Therefore, when the vehicle starts moving, the eddy current speed reducer does not return to the non-braking position, and the smooth start of the vehicle is not hindered. FIG. 1 is a schematic block diagram of a control device of an eddy current type reduction gear according to the present invention. The eddy current type reduction gear A includes a braking drum 2 as a braking body coupled to an output shaft 17 of a transmission.
5 and a magnet support wheel 27 that is axially movable along a fixed frame 24 disposed inside the braking drum 25.
The fixed frame 24 is an annular member having an inner space with a rectangular cross section. The plurality of (preferably three) actuators B coupled to the end wall 23 of the fixed frame 24 cause the magnet support wheels 27 to move into the braking position shown in FIG. And is driven.
The magnet supporting wheel 27 has a large number of permanent magnets (hereinafter simply referred to as magnets) 26 on its outer peripheral wall at regular intervals in the circumferential direction,
Are coupled so that the magnetic poles facing the inner peripheral surface are alternately different in the circumferential direction. The actuator B has a cylinder 21 fitted with a piston 21, and a rod 28 projecting from the piston 21 to the inner space of the fixed frame 24 is connected to a magnet support wheel 27. One of the two end chambers 20 and 22 of the actuator B is selectively connected to the air tank 10 and the other to the atmosphere by the electromagnetic switching valve 12. When the electromagnetic switching valve 12 excites the electromagnetic coil, the valve body moves to the illustrated braking position. Solenoid switching valve 1
2. When the electromagnetic coil is demagnetized, the valve body moves leftward due to the spring force, the pressurized air in the air tank 10 is supplied to the end chamber 22 of the cylinder 19, and the end chamber 20 of the cylinder 19 is released to the atmosphere. Is done. The magnet support wheel 27 moves to the left along with the piston 21, and the eddy current type reduction gear A switches to the non-braking position. The eddy current type reduction gear A is not limited to the drum type, but may be a disk type. Actuator B may be a hydraulic actuator or an electromagnetic actuator. An electromagnetic switching valve 12 is a release switch 13 which is opened and closed by an output of an electronic control unit 9 from a power supply battery 14.
Is passed through. An electronic control unit 9 for controlling the eddy current type speed reducer A switches the effectiveness of the eddy current type speed reducer A to two levels depending on whether or not there is a load and the retarder switch 3 disposed on the steering cylinder 4 supporting the handle 2. Empty switch 5 arranged on the instrument panel, an accelerator sensor 6a for detecting the release position of the accelerator pedal 6, and a clutch pedal 8
Sensor 8a for detecting the release position of the transmission, and the transmission 1
The braking condition is determined based on each input signal from a vehicle speed sensor 18 disposed opposite to the output shaft 17 and the release switch 13 is closed by the output signal. Further, the stop condition of the vehicle is determined, and the release switch 13 is opened by the output signal. Reference numeral 7 denotes a brake pedal. Since the vehicle equipped with the automatic transmission does not have the clutch pedal 8, the crankshaft 16a of the engine and the input shaft (not shown) of the transmission 16 are used instead of detecting whether the clutch pedal 8 is in the release position. The electronic control unit 9 determines whether or not the clutch is in the connected state based on the rotation difference. According to the present invention, when the accelerator pedal 6 and the clutch pedal 8 are released, the retarder switch 3 is closed, and the vehicle speed is equal to or lower than the predetermined value Vc (the vehicle speed may be 0),
The electronic control unit 9 generates a signal to open the retarder switch 3 and returns the eddy current type reduction gear A to the non-braking position just before the actuator B stops the vehicle. FIG. 2 is a flowchart of a control program for the electronic control unit 9 comprising a microcomputer for performing the above-described control. In the figure, p11 to p18 represent each step of the control program. This control program is repeatedly executed at predetermined time intervals. The control program starts at p11,
At p12, it is determined whether or not the accelerator pedal 6 is released. If the accelerator pedal 6 is not released, p
At 13 the release switch 13 is closed and the process ends at p18. If the accelerator pedal 6 is released at p12, it is determined at p14 whether the clutch pedal 8 is released. If the clutch pedal 8 has not been released, the process proceeds to p13. If the clutch pedal 8 has been released, it is determined at p15 whether the retarder switch 3 is closed. If the retarder switch 3 is not closed, proceed to p13. If the retarder switch 3 is closed,
At p16, it is determined whether or not the vehicle speed is lower than a predetermined value Vc (for example, 5 km / h). If the vehicle speed is higher than the predetermined value Vc, the process proceeds to p13. If the vehicle speed is lower than the predetermined value Vc, the release switch 13 is opened at p17 and the electromagnetic switching valve 12 is opened.
And the actuator B returns the eddy current reduction device A to the non-braking position. The present invention provides an eddy current type speed reducer of a type in which a magnet support wheel is separated from and attached to a brake disk, instead of a brake drum, and a magnet support wheel and a movable magnet which are immovable inside a brake drum. An eddy-current reduction gear of the type that switches from the non-braking position to the braking position by arranging the supporting wheel and rotating the movable magnet supporting wheel by the actuator forward and backward by the pitch of the magnet arrangement pitch. Applicable. As described above, according to the present invention, even if the retarder switch is closed, the accelerator pedal and the clutch pedal are released to stop the vehicle, and when the vehicle speed falls below a predetermined value,
The energizing circuit of the electromagnetic switching valve opens, and the actuator works to return the eddy current type speed reducer to the non-braking position. Therefore, when the vehicle starts, the eddy current type speed reducer does not return to the non-braking position, and the vehicle starts smoothly. Is not disturbed. When the vehicle speed is equal to or less than a predetermined value (for example, 5 km / h), the eddy current type speed reducer is controlled by the electronic control unit 9 so that the eddy current type speed reducer does not operate. When the vehicle is accelerated again, the fuel consumption is saved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a control device for an eddy current type reduction gear according to the present invention. FIG. 2 is a flowchart of a control program of the control device. [Description of Signs] A: Eddy current type reduction gear B: Actuator 3: Retarder switch 6a: Accelerator sensor 8a: Clutch sensor 9: Electronic control device 12: Electromagnetic switching valve 13: Release switch 17: Output shaft 18: Vehicle speed sensor 25 ： Brake drum 27 ： Magnet support wheel

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60L 7/28 B60T 7/12

Claims (1)

(57) Claims 1. A braking position in which a magnet support wheel applies a magnetic field by an actuator and a non-braking position in which a magnetic field is not applied to a rotary braking body coupled to an output shaft side of a transmission of a vehicle. In the eddy current type speed reducer which is driven to be switched to the above, when the accelerator pedal and the clutch pedal are in the release position and the vehicle speed is lower than a predetermined value, the actuator is switched to the non-braking position in the energizing circuit of the electromagnetic switching valve for controlling the actuator. A control device for an eddy current type speed reducer, wherein a release switch is inserted and connected.