JPS6347526A - Clutch control device for vehicle loading automatic transmission - Google Patents

Abstract

PURPOSE:To favorably maintain the connecting/disconnecting property of a clutch and prevent seizing, deterioration and the like by obtaining the correcting quantity of a clutch engaging quantity corresponding to the detected signal of a clutch circulating oil temp. by a converting means, and carrying out a clutch control by subtracting said correcting quantity. CONSTITUTION:An ordinary clutch engaging quantity f1 which is not corrected is obtained, an oil temp. T is detected by an oil temp. sensor 12, and a clutch engaging quantity f(T) to be corrected is obtained from the oil temp. T referring to a memory and made the correcting quantity f2 of the clutch engaging quantity. A desirable clutch engaging quantity F with respect to the oil temp. T is one in which the correcting quantity f2 is subtracted from the clutch engaging quantity f1. Therefore, the engaging correcting quantity f2 is subtracted form the engaging quantity f1 to obtain the clutch engaging target quantity F, and a clutch actuator 13 is energized so that a clutch disk 9 attains the clutch engaging target quantity F. Thereby, even if the oil temp. T is varied, the clutch engaging quantity is corrected by the amount of the function f(T) of the oil temp. T to obtain the desirable engaging quantity F, enabling the friction coefficient of a friction face to be kept nearly constant even if the oil temp. T is varied.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application 9'f) The present invention relates to a clutch control device for a vehicle equipped with an automatic transmission that corrects the engagement amount of a wet type clutch based on oil temperature.

(Prior Art) In recent years, vehicles equipped with automatic transmissions have been widely used to facilitate vehicle driving operations. Automatic clutches are used in such vehicles, and the hardware is mainly made of dry veneer. However, in large vehicles such as large trucks, the hardware is used to circulate lubricating and cooling oil to the clutch device. There are now many examples of using a wet type.

(Problems to be Solved by the Invention) However, in this type of wet clutch device, oil is circulated to lubricate the clutch mechanism and cool the clutch friction surface to reduce wear on the clutch friction surface. However, due to the change in viscosity caused by the change in oil temperature, the coefficient of friction of the clutch changes significantly as shown in FIG. When the oil becomes hot and its viscosity decreases extremely, an oil film is formed on the clutch friction surface when the clutch is engaged (during sleeve time), causing phenomena such as burning, cracking, and deterioration of the clutch friction surface.

Furthermore, the clutch facing swells due to oil immersion, and the thickness of the facing changes depending on the oil temperature.

Furthermore, the facing has been added to the clutch! When the pressure increases by 1, frictional heat is generated and the circulating oil temperature rises, sometimes exceeding the -F limit temperature of the facing.

As described above, the automatic transmission BJ! uses a wet clutch.
In heavy vehicles, there has been a problem in that the clutch connection/disconnection characteristics vary significantly depending on the oil temperature of the clutch circulating oil.

Furthermore, if the clutch is frequently used in a half-clutch state (clutch slip state) on congested roads, slopes, etc., there is a problem that in the worst case, the clutch may seize up and become impossible to drive.

The present invention cools the clutch circulating oil and at the same time corrects the clutch engagement amount in accordance with the oil temperature, thereby maintaining the clutch's engagement/disconnection characteristics in good condition and further preventing seizure, deterioration, etc. of the clutch friction surface. It is an object of the present invention to provide a clutch control device for an automatic transmission IaNS vehicle that prevents automatic transmission.

(Means for Solving the Problems) The present invention provides a clutch control device for an automatic transmission MG heavy vehicle using a wet clutch, which includes a detection means for detecting a clutch circulating oil temperature, and a clutch engagement correction based on the clutch oil temperature. Conversion means for determining quantities.

The problems of the prior art described above are solved by a clutch control device for a vehicle equipped with an automatic transmission, which is equipped with a correction means for correcting the clutch engagement amount using the clutch engagement correction amount obtained by the conversion means and controlling the clutch. be.

(Function) In the present invention, while the clutch circulating oil is forcibly cooled by the oil cooler, a correction amount of the clutch engagement amount is determined by the converting means in accordance with the signal from the clutch circulating oil temperature detecting means. By adding this correction amount to the normal clutch engagement amount, the desired clutch engagement amount is determined, and the clutch actuator is operated to perform clutch control. This cools the clutch circulating oil and changes the oil temperature. Since the clutch engagement amount is corrected accordingly, the friction coefficient of the clutch friction surface is always kept almost constant.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a configuration diagram of a wet clutch and its clutch control device. In Fig. 1, l is an oil tank for clutch circulation oil, 2 is a pump that sucks up oil from oil tank l and serves as a supply source, 3 is a nozzle that injects oil from pump 2, and 4 is a drive shaft of the vehicle. 5 is a sleeve retainer, 6 is a flywheel, 7 is a housing that accommodates the clutch, 8 is a pressure plate pressed by the flywheel 6, 9 is a clutch disc,
10 is an oil cooler that cools the oil injected from the nozzle 3; 11 is a strainer; 12 is an oil temperature sensor that detects the temperature of clutch circulating oil; and 13 is for controlling the amount of engagement between the clutch disc 9 and the flywheel 6. A clutch actuator 14 is an electronic control device that controls the operation of the clutch actuator 13, and 15 is a clutch stroke sensor. In such a wet clutch, oil from an oil tank 1 is sucked up by a pump 2, cooled by an oil cooler lO, and the cooled oil is injected from a nozzle 3 toward each part of the clutch.

In general, clutch circulating oil has a high viscosity at low temperatures and a low viscosity at high temperatures, so when the clutch engagement amount is the same, the friction coefficient of the clutch friction surface is large at low temperatures, and small at high temperatures. Become. Therefore, if the amount of clutch engagement is the same, the friction coefficient of the clutch friction surface changes depending on the temperature of the clutch circulating oil, and the dynamic friction torque of the clutch, that is, the torque at the time of clutch friction due to the transmission of power, differs. For example, when the vehicle starts, the clutch may slip more than necessary, or, conversely, the clutch may suddenly engage. In order to prevent such a phenomenon, in the present invention, an oil cooler 10 is provided in the path of the clutch circulating oil to forcibly cool the oil, and the cooled oil is injected from the nozzle 3 to each part of the clutch. I have to. Further, an oil temperature sensor 12 for clutch circulating oil is provided in the clutch housing 7 to detect the oil temperature, and the electronic control unit 2114 is configured to control the clutch engagement amount according to the detected oil temperature.

The operation of the electronic control unit 2114 that adjusts the clutch engagement amount in accordance with the oil temperature will be described below with reference to the flowchart of FIG.

The electronic control unit 2114 is composed of a microprocessor, and this microprocessor has a read-only memory (R
It is controlled according to a program stored in the OM). The flowchart in FIG. 2 shows the flow of processing by the microprocessor according to the control program stored in this ROM.

In FIG. 2, in step STI, the normal clutch engagement amount fl without any correction is determined.In step ST2, the oil temperature T is detected by the oil temperature sensor 12. Clutch engagement amount f, (T) to be corrected for oil temperature T
is stored in the memory in advance in the relationship shown in Fig. 3, and in step ST3, the clutch engagement amount f (T) to be corrected is determined from the oil temperature T detected in step ST2 by referring to the memory. This is the correction amount f of the clutch engagement amount.
Set it to 2. Desired clutch engagement i for the current oil temperature T
F is the clutch engagement amount fl that has not been corrected in any way by the correction amount f2 obtained in step ST3. Therefore, in step ST4, the clutch engagement amount fl
Then, in step ST5, the clutch actuator 13 is energized so that the clutch disc 9 reaches the clutch engagement target iF. As a result, even if the oil temperature T changes, the clutch actuator 13 is operated so that the clutch engagement amount is corrected by the function f (T) of the oil temperature T and becomes the desired clutch engagement amount F. Even if T changes, the friction coefficient of the clutch friction surface is always kept substantially constant, and there is no difference in the dynamic friction torque of the clutch.

(Effects of the Invention) As explained above, according to the present invention, since the clutch circulating oil is cooled by the cooling device, it is possible to prevent the oil viscosity from decreasing excessively, and to prevent seizure and deterioration of the clutch friction surface. This makes it possible to effectively prevent this from occurring. Furthermore, even if the clutch oil temperature changes, the clutch engagement is corrected by the amount of correction of the clutch engagement amount corresponding to this oil temperature, so the friction coefficient of the clutch friction surface is always kept almost constant. It is possible to effectively prevent shocks or unnecessary latch slips when the clutch is engaged or disengaged or when the clutch is half-engaged, thereby improving running sensitivity and effectively protecting the clutch facing.

[Brief Description of the Drawings] Fig. 1 is a configuration diagram of a clutch control device for a vehicle equipped with an automatic transmission according to the present invention, Fig. 2 is a flowchart showing the flow of its processing, and Fig. 3 is a diagram showing oil temperature T and clutch engagement. FIG. 4 is a diagram showing the relationship between the oil temperature T and the coefficient of friction. 6... Flywheel, 8... Pressure plate,
9...Clutch disc, 10...Oil cooler,
12...Oil temperature sensor, 13...Clutch actuator, 14...'-[Slave control device. Patent Applicant IsuC Automobile Co., Ltd. Representative Patent Attorney Minoru Tsuji Figure 1 δ --- 7 Retsushima Profile Figure 2 j Inner Temperature 7 3 Yuonto

Claims (1)

[Claims] In a clutch control device for a vehicle equipped with an automatic transmission using a wet clutch, a detection means for detecting clutch circulating oil temperature, a conversion means for calculating a clutch engagement correction amount based on the clutch oil temperature, and a clutch control device for determining a clutch engagement correction amount based on the clutch oil temperature. 1. A clutch control device for a vehicle equipped with an automatic transmission, comprising: a correction means for correcting a clutch engagement amount based on a clutch engagement correction amount and performing clutch control.