JPS5910192A - Controlling method for dc motor - Google Patents

Abstract

PURPOSE:To enable to control ultrafine angle of a DC motor by energizing the current which drives the motor in the first rotating direction for the first period and then energizing the current which drives the motor in the second rotating direction for the second period. CONSTITUTION:The operating alpha0 of a throttle valve 2 necessary to obtain the predetermined idle rotating speed is set on the basis of the designation signal of an idle up switch 42, and a period T0 in which a DC motor 18 is energized is determined to obtain the opening alpha0. The first period which is longer than the period T0 is set, the current which drives the motor in the first rotating direction is supplied to the motor 18, and a throttle valve 2 is opened and operated at the angle alphaa. Then, the current which drives the motor in the second rotating direction is supplied to the motor 18 for the second period which is shorter than the first period, thereby closing the throttle valve at the angle alphab.

Description

[Detailed description of the invention] The present invention relates to a method for controlling a DC motor.

Conventional control devices control the supply of current to a DC motor to rotate or slide a load that has resistance in the direction of rotation of the DC motor. The motor was rotated in a predetermined rotation direction and at a predetermined rotation angle.

However, in order to rotate the DC motor against the above load, there is a time delay for the DC motor to start rotating against the inertia and static friction of the drive system including the DC motor, and Due to the above-mentioned inertia when stopping after 9 rotations, and due to overactuation occurring because the dynamic friction coefficient is smaller than the static friction coefficient, the minimum rotation angle of the DC motor for a given load is automatically determined, and therefore the above-mentioned load The minimum operating amount was determined.

For this reason, it is difficult to perform minute control of the load, and the responsiveness deteriorates.

The present invention solves the above-mentioned problems, and provides a control method for controlling the energization of a DC motor in which a resistance force is applied in one rotational direction. By energizing according to the energizing time Ta, and then applying a current that drives in a second rotation direction opposite to the first rotation direction according to the second energizing time Tb, one energizing time To is To = Ta - K Tb However, The gist of this invention is a method for controlling a DC motor, which is characterized in that the DC motor is controlled so that the coefficient is based on the difference in the resistance force in the first rotation direction and the second rotation direction. It is something to do.

An embodiment of the present invention will be described below with reference to FIGS. 1 to S.

Reference numeral 2 denotes a throttle valve disposed in the intake passage B of the carburetor 4; 9 its rotation is controlled by an accelerator pedal (not shown); and an idle control device having a plunger 1o that comes into contact with a lever 8 fixed to the throttle valve 2; 12 controls the fully closed position at idle. 14 is an operating circuit of the idle control device 12.

The idle control device 12 includes a case 16. which is fixedly arranged on the carburetor 4. DC motor 18 arranged inside the case 16. Worm gear 20 formed on the rotating shaft of the DC motor 18. A sliding shaft 24 having a worm wheel 22 that engages with the worm gear 20. It includes a threaded portion 26 formed on the sliding shaft 24 and the plunger 14.

28 is a switch device for detecting the position of the end 30 of the sliding shaft 24, which includes a first fixed contact 32, a second fixed contact 54,
It has a movable contact 36 that is always elastically biased in the direction of the end portion 30, and when the sliding shaft 24 is at the left end position in the figure, the movable contact roller 6 and the first fixed contact 62 are in contact with each other, and the sliding shaft 24 is at the right end position in Figure 1. Movable contact 3
6 and the second fixed contact 34 are configured to be in contact with each other.

The operating circuit 14 includes (1) an engine rotational speed detection device 40 (not shown); (9) an idle up switch 42 that issues an instruction to open the throttle valve 2 to a predetermined opening according to a load such as an electrical load (not shown) or a cooler compressor load; an idle detection switch 46 disposed at the tip 44 of the plunger 1o to detect contact with the lever 80 and indicate that the throttle valve 2 is in the idle position; and a switch device 28 for detecting the position of the sliding shaft 24. Based on the signal, the energization to the DC motor 18 is controlled to rotate and drive the DC motor 18 in the forward direction or in the reverse direction.

48 is the second coming.

The operation of the above embodiment will be explained below.

The illustrated state shows a normal idling operating state.

The throttle valve 2 is held at a substantially fully closed position by an idle stopper (not shown).

When an electrical load due to turning on the headlights tJ'K or a cooler compressor load due to cooler operation is applied, a signal instructing the idle amplifier switch 42 is inputted to the operating circuit 14. The idle amplifier rotation speed during idling operation of the engine is set according to the electrical load, cooler compressor load, etc., and in order to obtain the idle up rotation speed, the throttle valve 2 is opened to a predetermined opening. The operation of 14 will be explained below.

First, based on the instruction signal of the idle 7 knob 42, the throttle MELF 2 opening degree α0 necessary to obtain a predetermined idle rotation speed is set, and the DC motor 18 is energized to obtain the opening degree. A time To is determined.

Next, a first time Ta that is sufficiently longer than the time To is set, and by supplying current along the first time Ta, the DC motor 18 is driven to rotate in the first rotational direction. At this time, the throttle valve 2 is opened in the opening direction at an angular velocity Wa, and the opening angle color becomes α1a-Ta-Wa.

Next, after the first time Ta has elapsed, a current in the opposite direction is supplied during a second time Tb, which is shorter than the first time Ta, so that the DC motor 18 is rotated in the opposite direction to the first rotation direction. Rotation drive is performed in the rotation direction of 2. At this time, throttle valve 2
is closed in the closing direction with an angular velocity, and the closing angle from the opening angle peak is αb=Tb-Wb. At this time, V/b is smaller than Wa due to the influence of the closing spring of the throttle valve 2 (not shown).

Wb = K Wa However, ≧1 They have the following relationship.

Therefore, the opening angle α0 of the throttle valve 2 is.

α0-αa-αb =　　Ta　Wa　　-Tb　Wb ”” (Ta K Tb) Wa becomes.

FIG. 3 shows the change over time of the current supplied to the DC motor 18. On the one side, the current for opening the throttle valve 2 is -
The side shows the current that closes the throttle valve 2. Time j+ indicates the start of flow of current on the + side, j2 indicates the start of flow of current on one side after stopping the current on the + side, and t3
indicates interruption of current. Here, Tb' is Tb' = K - Tb, ie.

To = Ta −K Tb It shows.

Furthermore, the operating circuit 14 includes a rotational speed detection device 40.
A signal is input, and when the idle speed of the engine does not reach the target value or exceeds the target value by opening the throttle valve 2, it is controlled to match the target value by the same operation as described above. Ru.

In the actuating circuit 14, the first fixed contact 62 of the switch device 28 indicates the left end position of the sliding shaft 24;
When a failure of the rotational speed detection device 4o occurs, the second sliding shaft 24 is operated to hold the sliding shaft 24 at the left end position.
The fixed contact 34 indicates the right limit position of the sliding shaft 24,
Regulate excessive operation.

As is clear from the above work, even if the opening angle hook of the throttle valve 2 is smaller than the minimum rotation angle of the throttle valve 2, the current that drives the DC motor 18 in the forward rotation direction is first applied to the first The energization time To in the opening operation direction is set by applying current along the energization time Ta and then applying a current that drives in the reverse rotation direction along the second energization time TbK.

To = Ta - K Tb However, ■(≧1) This has the effect that the opening operation angle of the throttle valve 2 can be obtained by setting the time corresponding to the angle less than or equal to the minimum rotation angle.

Furthermore, according to this embodiment, the throttle valve 2 has good responsiveness and minute angle control can be achieved without using an excessively high torque DC motor, resulting in an overall reduction in size and weight.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing one embodiment of the present invention, FIG. 2 is a sectional view taken along the arrow T in FIG. 1, and FIG. 3 is an operational characteristic diagram of one embodiment of the present invention. 2: Throttle valve, 4: Carburetor. 8 Nilever, 12; Idle control device.

Claims (1)

[Scope of Claims] A control method for controlling energization of a DC motor on which a resistance force is acting in the rotational direction, wherein a current for driving the DC motor in a first rotational direction is energized according to a first energization time Ta. Then, a current for driving in a second rotational direction opposite to the first rotational direction is applied according to the second energization time Tb, thereby reducing the 9 energization time TO to To = Ta −K
A method for controlling a DC mortar, characterized in that Tb is controlled to be a coefficient based on the difference between the first rotation direction and the second rotation direction.