JPS63137045A - Control device for automatic clutch for vehicle - Google Patents

Abstract

PURPOSE:To prevent the abnormal blow-up of an engine at the time of start by changing the clutch torque characteristic to the high-rising rate characteristic using the engine rotating speed acceleration and the throttle opening acceleration as a function to control the starting clutch torque in proportion to the engine rotating speed. CONSTITUTION:A start mode is judged by an electronic control unit 20 based on the engine rotating speed Ne, throttle opening theta, car speed V, and R, D, Ds signals of the travel range, the clutch current is determined, and the clutch control signal is outputted to control an electromagnetic powder type clutch 2. In this case, the engine rotating speed acceleration alphae due to the change of the engine rotating speed Ne and the throttle opening acceleration alphatheta due to the change of the throttle opening theta are determined, and the clutch torque characteristic is changed from the low-rising rate characteristic to the high-rising rate characteristic based on correction values obtained from alphae and alphatheta. At the time of a fully opened start, the clutch torque characteristic is transferred to the high-rising rate characteristic, thus the abnormal blow-up of an engine is prevented.

Description

[Detailed description of the invention] [Industrial application field]

The present invention is 11! Regarding the automatic clutch control system installed in both drive systems to electronically control the clutch torque,
More specifically, it relates to variable stall control at the time of starting. Many automatic clutches for vehicles of this type, such as electromagnetic clutches, have already been proposed by the applicant. Most of the time, the accelerator pedal and shift lever are operated in transient states such as when starting, and in steady states after the clutch is directly connected. The clutch torque is optimally controlled in relation to driving conditions, engine status, etc., and furthermore, in combination with a manual transmission or a belt-type continuously variable transmission, appropriate control is performed. Particularly in recent years, electronic control of not only engines but also drive system clutches, transmissions, etc. has progressed, and there is a tendency for automatic clutches to be even more precise (control 9FJ-).

[Prior Art] Conventionally, in the above-mentioned automatic clutch for vehicles, clutch torque i and II control in the start mode have been controlled by, for example,
There is a prior art disclosed in Japanese Patent No. 0-161224, which describes that the clutch torque at the time of starting is determined as a function of the engine speed, and is controlled so that it increases in proportion to the engine speed. In addition, variable stall control has been proposed that takes into account the upper bound state of the engine rotational speed and the striking acceleration in this case, and lowers the stall rotational speed as the acceleration increases, shifting to a direction where the upper bound rate of the clutch torque is larger. . Such variable stall control makes it possible to engage the clutch cleanly and in accordance with the driver's intention in accordance with the rise in engine speed and its degree. [Problems to be Solved by the Invention] Incidentally, the above-mentioned prior art does not take into account the running condition of the vehicle at the time of starting. In other words, both starting the vehicle from a stopped state and restarting the vehicle from a coasting state with the clutch released,
-m is 11111. Therefore, when restarting the vehicle in a coasting state, a transient slipping feeling and engine revving occur, especially when the clutch torque increases. Therefore, when starting by pressing the accelerator, it is desirable to initialize the clutch torque depending on whether the vehicle is stopped or coasting. In addition, the acceleration of the engine rotational speed changes little with respect to situations such as sudden acceleration or slow acceleration at the time of starting, and it is not possible to clearly detect the starting state from this alone. Furthermore, it is desirable to quickly shift to a characteristic in which the clutch torque increases at a high rate to avoid transient racing when fully developed, and to shift relatively slowly and smoothly engage when starting at low speed. However, the above-mentioned engine speed acceleration alone is insufficient for variable stall control in relation to such engine load. The present invention has been made in view of the above points, and an object of the present invention is to provide a control device for an automatic clutch for a vehicle that has characteristics that are smooth and have little shock in various starting situations. It is said that

[Means to solve the problem]

In order to achieve the above object, the present invention changes the clutch torque characteristic from a low rate of increase characteristic to a sewing characteristic of a high rate of increase in a control system that makes the clutch torque characteristic at the time of start proportional to the engine speed, The speed of change is controlled as a function of both the speed of change of the throttle opening, the acceleration of the engine rotational speed, and the speed of change of the throttle opening.

[Function 1] Based on the above configuration, in variable stall control that changes the clap-torque characteristic at the time of start from a characteristic with a low upper limit rate to a characteristic with a high rate of increase, the larger the engine speed acceleration, the more the throttle opening The larger the value, the more quickly the change will occur. Thus, according to the present invention, it is possible to adapt the rise of the clutch torque at the time of starting the vehicle to the starting situation. [Embodiments] Hereinafter, embodiments of the present invention will be described based on the drawings. Referring to FIG. 1, the overall configuration of a drive system that combines an electromagnetic clutch and a belt-type continuously variable transmission will be described. The engine 1 is connected to a continuously variable transmission 4 via an 'im powder type clutch 22 forward/reverse l171 conversion device 13, and is connected to a continuously variable transmission 4 from a continuously variable transmission i4 to a set of transmission gears V5. Output @6. Transmission is configured to a drive shaft 9 via a differential gear 7 and an axle 8. The electromagnetic powder clutch 2 has a drive member 2a on the engine crankshaft 10, and a driven member 2b on the input shaft 11 with a clutch coil 2C. Then, due to the clutch current flowing through the clutch coil 2C, both members 2a,
Electromagnetic particles are combined and accumulated in a chain in the gap between 2b, and the resulting binding force can variably control clutch engagement and disconnection and clutch torque! l-ru. The forward/reverse switching device 3 is configured in a synchronous meshing manner with a gear 7, a hub, or a sleeve between the input shaft 11 and the main shaft 12 of the transmission, and has at least a forward position where the input shaft 11 is directly connected to the main shaft 12; It has a retreat position where the rotation of the input shaft 11 is reversed and transmitted to the main shaft 12. The continuously variable transmission 4 has a main shaft 12 and a subshaft 13 arranged parallel to the main shaft 12, and a primary pulley 14 with variable boob spacing equipped with a hydraulic cylinder 14a is attached to the main shaft 12, and the subshaft 13
A secondary pulley 15 equipped with a hydraulic cylinder 15a is provided like Irj1. Also, both pulleys 14°15
A drive belt 16 is wound around both cylinders 14a.
, 15a are configured in the hydraulic control circuit 17. Both cylinders 14a and 15a IC supply line pressure according to the transmitted torque to apply a boolean pushing angle force, and the primary pressure causes the driving belt 16 to wrap around the pulley 14.15 steplessly by changing the diameter ratio. It is configured to control the speed change. Next, the electronic control system of the electromagnetic powder clutch 2 and the continuously variable transmission 4 will be explained. Engine speed sensor 19 for engine 1. No-boot and secondary pulley rotation speed sensors 21, 22
. a sensor 23 that detects the operating status of the air conditioner or chili;
It has 24. In addition, the shift lever 25 of the operation system is
It is mechanically connected to the forward/forward switching device 3, and the reverse
R), Drive (D), Sporty Drive <1)s)
The shift position sensor 26 detects each range. Further, the accelerator pedal 27 has an accelerator switch 28 for detecting the accelerator depression state, and a throttle opening sensor 29 is disposed on one side of the throttle. The signals from the switches and sensors are input to the electronic control unit 20 and processed by software using a microcomputer or the like. Then, the clutch control signal output from the electronic control unit 20 is input to the electromagnetic powder clutch 2, and the speed change υ control signal and line pressure control signal are input to the hydraulic control circuit 17 of the continuously variable speed n4 to perform each control operation. It has become. In FIG. 2, the electromagnetic clutch control system of the control unit 20 will be mainly explained. First, the sensors 21, 22. 29 primary pulley rotation speed Np. The signals of the secondary pulley rotation speed Ns and the throttle opening θ are input to the speed change control section 3o,
A control signal corresponding to the shift speed di/dt is output. In addition, the engine rotation speed Ne of the sensor 19, the throttle rva
o, actual gear ratio i (NS /Nl) ) (The D signal is input to the line pressure control component 31 and outputs a control signal according to the target line pressure. Then, these control signals are sent to the continuously variable transmission 4. In the electromagnetic clutch control system, reverse excitation mode judgment is performed in which the engine rotational speed Ne and the driving range signals of R and D.Os of the shift position sensor 26 are input. For example, in the case of N e < 300rl)I, or in the case of parking (P) or neutral (N > range), the output determination unit 33 determines that the reverse excitation mode is set, and the output determination unit 33 outputs a slight wi in the opposite direction from the normal one. Then, the residual magnetism of the i-magnetic powder clutch 2 is removed and it is completely released. Also, the judgment output signal of this reverse excitation mode judgment section 32. The depression signal of the accelerator switch 28 and the secondary boot rotation speed sensor 22 It has an energization mode determination section 34 to which the medium speed V signal is input, and determines the running state such as starting, and this determination signal is used in starting mode, drag mode and straight 11 mode.
;! Each current setting section 35, 36 of the iT needle. 37. The starting mode current setting unit 35 separately sets starting characteristics in relation to the engine rotation aNe and the like in the case of normal starting or starting using an air conditioner or a choke. Then, throttle rM degree θ, vehicle speed V. R. D. The clutch current is set by correcting the starting characteristics according to each driving range of Ds. The drag mode current setting unit 36 determines a slight drag current when the accelerator is released at low vehicle speed in each range of R, D, and Ds, and generates drag torque in the electromagnetic powder clutch 2 to reduce play in the belt and drive system. to ensure a smooth start. In this mode, the current is set to zero until just before the vehicle stops after the clutch is released in the D range, to ensure coasting performance. The direct connection mode current setting section 37 is connected to the R. D. In each range of Ds, the direct current is determined based on the relationship between vehicle speed V and throttle opening θ, and 'M1
1. The powder type clutch 2 is fully engaged and power is saved in the engaged state. These current setting sections 35. The output signals of 36 and 37 enter the output determination section 33,
The clutch current is determined according to the instructions, and the map for each mode is as shown in Figure 3. An embodiment of start control in the electromagnetic clutch control system will be described with reference to FIG. 4Q. The starting mode current setting section 35 determines the energization mode. Engine u rotation speed Nc, throttle opening, vehicle speed V. Driving range R. D. It has a starting mode determining section 40 which receives each signal Ds and determines the starting mode, and based on the result of this determination, a current setting section 41 determines the clutch current lc.
It is output from the output section 42. The current setting unit 41 determines the clutch ff current IC in proportion to the engine rotation speed Ne°,
Further, the stall rotational speed is changed by the correction value C to perform variable stall control, which is expressed as follows. Ic −f(Nl >, Ni −Ne −<I
+C) Also, regarding after the start of the variable stall system, it has an acceleration calculation unit 43 into which the engine rotation speed No is input, and calculates the acceleration 11ae from ae −(Nen-1>−<Nen). On the other hand, it has a throttle opening change rate calculating section 47 to which the throttle opening degree θ is input, and the change rate αθ is similarly calculated by αθ−(Qn−1)−Qn, and these acceleration α0 and change rate αθ are calculated. The correction value is input to the correction value setting section 44. The correction value setting unit 44 sets the acceleration αe and the rate of change α
Using θ, the correction value C is falsified from time to time by 1 e (Ic3 +Kt correction αθ (K1.Kz is a constant) on Cn −cn−t +, and this correction mc is input to the current setting section 41. Further, it has a previous energization mode determination section 45 to which a signal for energization mode determination is input immediately after the start of the variable stall control, and determines whether or not the accelerator depression is the first time based on the previous energization mode.This determination result The signals Co and vehicle speed V are input to the initial value setting unit 46, and when the accelerator is depressed for the first time, the initial value Co is determined by the vehicle running state at that time, that is, a function of the vehicle speed V. Here, as shown in ) in FIG. , Go is given as an increasing function of .This initial value c is input to the correction value setting section 44 and initialized by C=Co. The operation of the control device is explained in the fifth section.
This will be explained with reference to the flowchart shown in the figure and the starting characteristics shown in FIG. First, when the axle is released, the vehicle is in drag mode, and the drag current fd shown in FIG. 6 flows, and the clutch 2 is stopped or coasting in a released state. On the other hand, if the accelerator is depressed, the start mode determination unit 40
It is determined that it is in launch mode. When the accelerator is depressed for the first time, an initial value CO is determined by the initial value setting unit 4G according to the determination result of the previous mode determination unit 45 according to the vehicle speed at that time, and a correction value C using this initial value Co is used to calculate the clap-current re. is calculated by the current setting section 41. Therefore, when the vehicle starts from a stop, since Co is at its lowest value at ■-○, the torque rises along with the clutch current 1c along curve A in FIG. 6 where the stall rotational speed is maximum and the rate of increase is minimum. Then, when the engine speed Ne increases by pressing the accelerator, the acceleration r! Then, the calculation unit 43 calculates the acceleration αe, and the throttle opening change rate calculation unit 47 calculates the change rate αθ, and based on these, the correction value Cn is determined. and Co<C
In the case of n, variable stall control is started, and the upper bound rate is shifted from the characteristic curve A with a low upper bound rate to the characteristic curve B with a high upper bound rate in FIG. Here, the value of Cn increases rapidly as the engine speed acceleration αe and the rate of change αθ of the throttle opening degree increase, and therefore the value of Cn quickly changes from 8 to 8 as shown by curve 21 in FIG. 6, and the clutch torque suddenly rises and the clutch engages quickly. On the other hand, in the case of a quiet start where the engine speed acceleration αe and the throttle opening change speed αθ are small,
Since the change in Cn is also small, the transition from 8 to 8 occurs slowly as shown by the curve L1 in FIG. 6, and the rise of the clutch torque gradually increases, resulting in smooth clutch engagement. Although one embodiment of the present invention has been described above, it can also be applied to automatic clutches other than electromagnetic clutches. Effects of the Invention 1 As described above, according to the present invention, in clutch torque control using variable stall at the time of starting, the speed of change in throttle opening is taken into account in engine rotational speed acceleration. The starting characteristics will be adapted to the intention of the person. In particular, the characteristics at the time of a sudden start become more appropriate, and the acceleration performance improves.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram showing an embodiment of the control device of the present invention, Fig. 2 is a block diagram of the rest of the electronic control system, Fig. 3 is a map diagram of each mode, and Fig. 4 O is the main part. Block diagram of 4th
FIG. 5B is a characteristic diagram of initial values, FIG. 5 is a flowchart diagram, and FIG. 6 is a starting characteristic diagram. ” 2...Electromagnetic powder clutch, 20...Electronic control 2
0 unit, 35... Starting mode current setting section, 40...
... Starting mode determination section, 41... Current setting section, 44.
...Correction value setting section, 45...Previous date judgment section, 46.
...Initial value setting section, 47... Throttle degree change speed setting section. Patent Applicant: Fuji Heavy Industries Co., Ltd. Agent, Patent Attorney: Nobu Kobashi, Patent Attorney: Toshin Mura, Figure 6, Figure 5 ED

Claims (1)

[Claims] A control system that makes the clutch torque characteristic at the time of start proportional to the engine speed, the clutch torque characteristic being changed from a characteristic with a low rate of increase to a characteristic with a high rate of increase, and the rate of change is controlled by a throttle. 1. A control device for an automatic clutch for a vehicle, characterized in that control is performed as a function of both the speed of change in opening degree, the acceleration of engine rotational speed, and the speed of change in throttle opening degree.