JPH03194218A - Controller of electromagnetic clutch for car - Google Patents

Abstract

PURPOSE:To easily carry out minute clutch control by multiplying different coefficients to an output of a clutch electric current computation means in accordance with a clutch control mode and by controlling a clutch electric current in accordance with deflection between the output and an output of a clutch electric current detection means. CONSTITUTION:An analog clutch electric current signal is outputted from a D/A converter 25 and to which a coefficient K corresponding to a clutch control mode is multiplied by a multiplier 22. Its output is inputted to a comparator 14, and a clutch electric current Ic is controlled in accordance with deflection after being compared with a feedback signal SF. The multiplier 22 is made to carry out multiplication by adding a multiplication signal SM from a clutch electric current computation means 2 in accordance with a clutch control mode. With this constitution, it is possible to improve a clutch torque resolution to a conventional 1/K by way of multiplication of a coefficient of 1.0 in a start mode or a drag mode and to carry out minute clutch torque control. Additionally, it is needless to make the D/A converter have a higher resolution and is possible to constitute it less expensive.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for an electromagnetic clutch for a vehicle.

[Conventional technology]

A conventional device of this type (Japanese Unexamined Patent Publication No. 1431/1983) is shown in FIG. In the figure, 1 is clutch current control means;
2 is a clutch current calculating means, 3 is an on-board battery, and 4 is an electromagnetic clutch consisting of a clutch coil 41 and a slip ring 42. 11.12 is an output transistor; 13 is a clutch current detection resistor; 14 is a comparator for detecting the deviation between the analog clutch current command signal SIA given from the clutch current calculation means 2 and the clutch current feedback signal SF; 15 is a comparator 14 1617 is a freewheeling diode, and 18.19 is a reverse excitation resistor for causing a minute reverse excitation current to flow through the electromagnetic clutch 4 when transistors 11 and 12 are both off. , 20 and 21 are output terminals of the clutch current control means 1, which are connected to the electromagnetic clutch 4. The clutch current calculation means 2 includes an interface circuit 23 that inputs travel control information S and engine control information SE and shapes the waveforms, a computer 24 that calculates a digital clutch current command signal SID, and a digital current command signal SI.
It is comprised of a D/A converter 25 that converts D into an analog current command signal SIA.

In the above configuration, the clutch current calculation means 2 inputs the traveling control information S and the engine control information SE to the interface circuit 23, and the computer 24 calculates the digital clutch current command signal Sll+ corresponding to the clutch torque from these information. The D/A converter 25 converts this into an analog value SIA and outputs it. When the flange is released, both transistors 11 and 12 are turned off by the output of the pulse width modulator 15 and the clutch release signal S0 from the clutch current calculation circuit 2, and a minute reverse excitation current is applied to the electromagnetic clutch 4 via the resistor 18 and 19. flows. Furthermore, when the clutch is connected, the transistor 12 remains on, and the feedback value S of the clutch current detected by the resistor 13 is
The comparator 14 compares the command value seA with the command value seA, and applies the deviation to the transistor 11 via the pulse width modulator 15 to turn on and off the transistor II, thereby increasing the clutch current I.
Control C. Note that when the transistor 11 is off, a return current flows through the diode 16.

Another conventional example is disclosed in Japanese Unexamined Patent Publication No. 62-231822, in which the clutch current is changed depending on the running condition of the vehicle/or the operation condition of the driver.

Additionally, the clutch torque capacity is generally larger than the maximum engine torque to eliminate clutch slippage in direct-coupling running conditions, but a small current motor is often used in start mode or drag mode.

[Problem to be solved by the invention]

However, in the conventional device described above, in order to improve the clutch torque resolution in start mode or drag mode, it is necessary to improve the digital control resolution from, for example, 8 bits to 10 to 12 bits. As the number of computer output ports increases, D/
It is also necessary to improve the resolution of the A conversion section 25, which makes it expensive.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a control device for a vehicle electromagnetic clutch that is inexpensive and capable of improving clutch resolution.

[Failure to solve the problem]

The control device for an electromagnetic clutch for a vehicle according to the present invention includes a multiplication means for multiplying the output of the clutch current calculation means by a different coefficient depending on the clutch control mode, and a deviation between the output of the multiplication means and the output of the flange current detection means. A clutch current control means for controlling the clutch current accordingly is provided.

[For production]

In this invention, the calculated clutch current is multiplied by a different coefficient depending on the clutch control mode, and the clutch current is controlled according to the deviation between this multiplied value and the detected value of the clutch current. Therefore, in the start mode or drag mode, the range is expanded by setting the multiplication coefficient to 1 or more.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figure shows the configuration of a control device for a vehicle electromagnetic clutch according to this embodiment, and 22 is a multiplier that multiplies the analog clutch current command signal SIA, which is the output of the D/A converter 25, by a coefficient K corresponding to the clutch control mode. And its output S'lA
= K-3IA is input to the comparator 14 together with the feedback signal S, and the clutch current 1c is controlled according to the deviation. A multiplication signal S8 is applied to the multiplier 22 from the clutch current calculation means 2 according to the clutch control mode, and multiplication is performed in accordance with this. The other configurations are the same as before.

FIG. 3 shows a specific configuration of the multiplier 22, where 30 is an operational amplifier, and its 10 input terminals receive an analog current command signal SI.
A is input. R1 and R2 are the setting resistances, 31 is a transistor, and R3 is a base resistance of the transistor 31. A multiplication signal SN from the computer 24 of the clutch current calculating means 2 is applied to the base of the transistor 31 in accordance with the clutch control mode, thereby turning the transistor 31 on and off. When transistor 31 is off,
When the multiplication coefficient is 1 and the transistor 31 is on, the multiplication coefficient K - RI + ' 2 ) is 1. Therefore, the digital current command signal 5l11 and the clutch current 1
The relationship between , is shown in Fig. 4, and when the clutch control mode is start mode or drag mode, the range is expanded by using K>1.0 as the multiplication coefficient.
Clutch torque resolution is improved. In addition, in the direct connection mode where the clutch current is large, the clutch current is set so as to obtain a latch torque that is larger than the normal engine torque, so the resolution of current control is lower than the clutch current that produces a clutch torque that is approximately equal to the engine torque. This is not necessary, and the multiplication coefficient is set to 1.0, which is the same as before.

〔Effect of the invention〕

As described above, according to the present invention, in the start mode or drag mode, by multiplying the command value of the clutch current by a coefficient of 1 or more, the range can be expanded and the resolution of the clutch torque can be improved.

Also, for this reason, the number of output ports of the computer increases and
It is not necessary to increase the resolution of the /A conversion section, and the structure can be constructed at low cost.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a device according to the present invention, Fig. 2 is a block diagram of a conventional device, Fig. 3 is a circuit diagram of a multiplier according to the present invention, and Fig. 4 is a diagram showing the relationship between a clutch current command value and a clutch current according to the present invention. It is a relationship diagram. DESCRIPTION OF SYMBOLS 1... Clutch current control means, 2... Clutch current calculation means, 4... Clutch, 13... Clutch current detection resistor, 22... Multiplier. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] Clutch current calculation means for calculating the current of the vehicle electromagnetic clutch in response to travel control information and engine control information, clutch current detection means for detecting the clutch current, and an output of the clutch current calculation means that differs depending on the clutch control mode. 1. A control device for an electromagnetic clutch for a vehicle, comprising a multiplication means for multiplying by a coefficient, and a clutch current control means for controlling a clutch current according to a deviation between an output of the multiplication means and an output of a clutch current detection means.