JPH03239822A - Automatic clutch controller for vehicle - Google Patents

Abstract

PURPOSE:To aim at optimum release and engagement during the operation of an anti-lock brake system (ABS) by providing a clutch release judgment means and a clutch engagement judgement means which are operated upon input of an operation signal and acceleration, respectively. CONSTITUTION:In case of wheel lock in a brake operation on a low frictional rod during traveling of a vehicle, the drive wheel lock is expected with abrupt decreases in vehicle speed, engine rotational speed and primary pulley rotational speed so that an anti-lock brake system (ABS) is operated. A clutch release signal is output from a clutch release judgment unit 40, and immediately, an electromagnetic powder type clutch 2 is released. In case of acceleration by depressing an accelerator pedal during the operation of the ABS, the clutch is engaged by a clutch engagement judgment unit 42 so as to eliminate unnecessary engine brake, thus realizing smooth acceleration.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an automatic clutch control device installed in a vehicle drive system that electronically controls clutch torque. This invention relates to clutch control when the anti-lock brake system (ABS) is activated.

[Conventional technology]

Generally, as a safety measure when braking a vehicle, even vehicles with continuously variable transmissions are being equipped with ABS in their brake systems. In a continuously variable transmission, when the ABS is activated, changes in wheel speed are transmitted to the primary pulley by the belt as the brake hydraulic pressure is reduced, and the rotational speed of the primary system is restored. Recovery may be delayed due to large squares. Therefore, in a drive system in which an automatic clutch is combined with a continuously variable transmission, it is desirable to improve the ABS performance by appropriately releasing the clutch when the ABS is activated.

On the other hand, if the clutch is released when the ABS is activated, the engine will start racing when the brake is released and the accelerator pedal is pressed to accelerate. For this reason, when the clutch is controlled to be disengaged when the ABS is activated, it is necessary to appropriately control the engagement to prevent the engine from racing during acceleration.

Therefore, conventionally, regarding the control when the ABS is activated in the above-mentioned automatic clutch for a vehicle, for example, Japanese Patent Laid-Open No. 47-3566
There are prior art techniques such as Japanese Patent No. 9 and Japanese Utility Model Application No. 1-125762. Here, it is shown that the clutch is immediately released when the ABS is activated, and the clutch is kept in the released state for a predetermined period of time even after the ABS is released.

[Problem to be solved by the invention]

By the way, in the prior art described above, since the clutch is immediately released when the ABS is activated, the effect of engine braking is lost early, and the effectiveness of the brake suddenly changes, which is undesirable. Furthermore, when the engine speed is high even when ABS is activated, the wheel speed recovers quickly even if the inertia mass is large as in a continuously variable transmission, so it is necessary to optimize the conditions for clutch release in this respect. Furthermore, if the clutch engagement condition is determined based on the time after ABS is released, the engine may run dry during acceleration, so it is necessary to take into consideration the acceleration time when optimizing the clutch engagement condition.

The present invention has been made in view of these points, and its purpose is to optimize clutch release and engagement when ABS is activated in a drive system that combines a continuously variable transmission and an automatic clutch. An object of the present invention is to provide a control device for an automatic clutch for a vehicle that can be used in a variety of ways.

[Means to solve the problem]

In order to achieve the above object, the automatic clutch control device of the present invention is a drive system that combines an automatic clutch with a continuously variable transmission. Clutch release determination means for releasing the automatic clutch when the engine speed becomes equal to or less than a set value when an activation signal is input to the anti-lock brake system during driving with the clutch engaged;
Clutch engagement determining means is provided for engaging the automatic clutch when the engine speed reaches a set value or more during acceleration during operation of the brake system.

[For production]

Based on the above configuration, the automatic clutch combined with the continuously variable transmission remains engaged even when the anti-lock brake system is activated when the engine speed is high, allowing for smooth recovery of wheel speed, etc. . When accelerating while the anti-lock braking system is operating, the automatic clutch is engaged at the set engine speed to prevent the engine from racing, preventing unnecessary engine braking and reducing the speed of the continuously variable transmission. The downshift will now be performed smoothly.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

Referring to FIG. 2, 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 electromagnetic powder clutch 21 and a forward/reverse switching device 3. Output shaft 6. Differential gear 7
The power is transmitted to the drive wheels 9 via the axle 8 .

The electromagnetic powder clutch 2 has a drive member 2a on the engine crank lO, and a driven member 2b on the input shaft U 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,
The resulting coupling force variably controls clutch engagement and clutch torque.

The forward/reverse switching device 3 is configured in a synchronized meshing manner between a human power shaft 11 and a primary shaft 12 by gears, a hub, and a sleeve, and has at least a forward position in which the input shaft 11 is directly connected to the primary shaft 12, and a forward position in which the input shaft 11 is directly connected to the primary shaft 12; and a retracted position where the rotation of the shaft 11 is reversed and transmitted to the primary shaft 12.

The continuously variable transmission 4 has a primary shaft I2 and a secondary shaft 13 arranged parallel to the primary shaft I2. 2 is provided with a primary pulley 14 with a pulley spacing of ++J, and the secondary shaft 13 is provided with a secondary pulley 15 that is similarly provided with a hydraulic cylinder 15a. In addition, primary pulley 14 secondary pulley 15
The drive belt is wound around the cylinder 14a for one day, and both cylinders 14a
, 15a are configured in the hydraulic control circuit 17. Then, line pressure corresponding to the transmission torque is supplied to both cylinders 14a and 1.5a to apply a pulley pressing force, and the primary pressure causes the primary pulley 14 of the drive belt to
．． The winding around the secondary pulley 15 is configured to change the ratio of diameters to perform stepless speed change control.

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 l. The continuously variable transmission 4 has a primary pulley and a secondary pulley rotation speed sensor 21, 22, and sensors 23 and 24 that detect the operating status of the air conditioner and choke. Also,
The shift lever 25 of the operation system is mechanically connected to the forward/reverse switching device 3, and is used for reverse (R), drive (D),
It has a shift position sensor 26 that detects each range of sporty drive (Ds). Furthermore, the accelerator pedal 27
is an accelerator switch 2 that detects the accelerator depression state.
8, and a throttle opening sensor 29 on the throttle valve side.
has.

The various signals from the switches and sensors are input manually 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 manually input to the electromagnetic powder clutch 2, and the shift control signal and line pressure control signal are input to the hydraulic control circuit 17 of the continuously variable transmission 4, so that each control operation is performed. It has become.

In FIG. 1, the electromagnetic clutch control system of the control unit 20 will be mainly explained.

First, the signals of the primary pulley rotation speed Np, the secondary pulley rotation speed Ns, the shift positions R, D, Ds, and the throttle opening θ of the sensors 2+, 22, 26, and 29 are input to the shift speed control section 30, and the signals are inputted to the shift speed control section 30 to control the shift speed. A control signal corresponding to di/dt is output. Also, the engine rotation speed Ne and the throttle opening θ of the sensor 19.

The signal of the actual gear ratio 1 (Ns/N15) is input manually to the line pressure control section 3I, which outputs a control signal corresponding to the target line pressure. These control signals are then manually applied to the continuously variable transmission 4 to control the line pressure to a predetermined level and to control the speed change.

The electromagnetic clutch control system includes a reverse excitation mode determination unit 32 in which parking (P) and neutral (N) signals other than the engine rotation speed Ne and R, D, and Ds of the shift position sensor 26 are manually operated. When Ne < 300 rpw or in the P or N range, it is determined that the mode is reverse excitation mode, and the output determination section 33 causes a minute 1@ flow in the opposite direction to the normal flow. Then, the residual magnetism of the electromagnetic powder clutch 2 is removed and it is completely released.

Also, the determination output signal of this reverse excitation mode determination section 32.

It has an energization mode determination section 34 that manually receives the depression signal of the accelerator switch 28 and the vehicle speed V signal of the secondary boot rotation speed sensor 22, and determines the running state such as starting, and this determination signal is used to determine whether the starting mode, drag mode, or Manually input each current setting section 35.3111°37 in direct connection mode.

The starting mode current setting unit 35 separately sets starting characteristics in relation to the engine rotation speed Ne, etc. in the case of normal starting or starting using an air conditioner or a choke. Then, the clutch current is set by correcting the starting characteristics based on each driving range of the throttle opening θ and the vehicle speeds VR, D, and Ds.

The drag mode current setting unit 36 determines a slight drag current when the accelerator is released at low vehicle speed in each of the R, D, and Ds ranges, 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 coupling mode current setting unit 37 determines the direct coupling current according to the relationship between the vehicle speed V and the throttle opening θ in each range of R, D, and Ds, fully engages the electromagnetic powder clutch 2, and
In addition, power is saved in the engaged state. These current setting sections 85
The output signals 36 and 37 are manually inputted to the output determining section 33, and the clutch current 1c is determined according to the instructions thereof.

In the electromagnetic clutch control system described above, clutch release/engagement control when ABS is activated will be described.

First, in the shift pattern of the continuously variable transmission shown in Fig. 3, the shift state during braking will be described. When braking with the accelerator released, the shift ratio changes from the minimum gear ratio i11 to the maximum gear ratio iL.
The minimum gear shift line j between and the minimum gear ratio 1.1! win
If the electromagnetic powder clutch 2 is engaged at this time, the engine rotational speed Ne and the primary pulley rotational speed Np are equal to the rotational speed N■in corresponding to the lowest shift line l1in. controlled at a constant rate. Therefore, when the ABS is activated, if the state of Ne≦N*in is maintained by the engagement of the electromagnetic powder clutch 2, the inertial mass will increase due to the downshift to follow the minimum shift line l sin, and the engine This is undesirable as it promotes braking effect and downshifting. That is, when the ABS is activated, it is desired to release the engine 1 in the continuously variable transmission 4, and in this respect, the set engine rotation speed N is higher than the rotation speed Nm1n of the lowest shift line JIll1n. A
This set engine speed N when BS is activated. The electromagnetic powder type clutch 2 is released and engaged in relation to the above.

Therefore, the direct connection mode signal of the direct connection mode current setting section 37,
It has a clutch release determination section 40 into which the ABS signal, engine rotation speed Ne, and secondary boot rotation speed Ns are input, and when the ABS signal is input manually while the electromagnetic powder clutch 2 is engaged in the direct connection mode, Ne< N. When the condition is met, the ABS mode current setting unit 41 outputs the output determination unit 33
Instructs the electromagnetic powder clutch 2 to be released. Here, the set engine rotation speed N at which the electromagnetic powder clutch 2 is released. is the third
As shown in Figure (b), when the secondary brake rotation speed Ns corresponding to the vehicle speed is high, it is set as an increasing function, and the electromagnetic powder clutch 2 is released early to increase the effectiveness of the brake.

In addition, in response to acceleration during ABS operation, the engine speed Ne, the secondary brake speed Ns, the accelerator depression signal of the accelerator switch 28, and the clutch release signal of the clutch release determination section 40 are input to the clutch engagement. It has a match determination section 42.

Then, the acceleration is determined based on the signal of accelerator depression, and Ne
If ≧No is reached and the clutch was previously released, the electromagnetic powder clutch 2 is engaged by the ABS mode current setting section 4I. In this case, since the continuously variable transmission 4 is shifting to a relatively high speed gear, the rise of the clutch current 1c is set smoothly to perform downshift control smoothly.

Next, the operation of the control device configured in this way will be explained as follows.
This will be described using the flowchart shown in the figure and the time chart shown in FIG.

First, when shifting to the driving range and starting by depressing the accelerator 27, the starting mode current setting section 35 is selected by the energization mode determining section 34 in the electromagnetic clutch control system. Therefore, the clutch current 1c is controlled to gradually increase in accordance with the increase in the engine speed Ne, and this clutch current 1c is controlled by the output determining section 33. The driving means 38 causes the flow to flow to the clutch coil 2C, producing a corresponding clutch torque. Therefore, the engine power is transmitted to the driven member 2b and subsequent parts of the electromagnetic powder clutch 2 according to the clutch torque to start running.In this case, in the case of a dry road surface, etc., the primary pulley rotation speed Np on the clutch output side
increases due to the characteristics of the clutch torque (clutch current) and road distance, and the vehicle speed V also increases. Then, the engine speed Ne and the brake rotation speed Np match relatively quickly,
When the direct coupling vehicle speed reaches v2, the direct coupling mode current setting section 37 is selected by the energization mode determining section 34. Therefore, from this point on, the direct coupling current IL flows through the clutch coil 2c, and the electromagnetic powder clutch 2 is maintained in the engaged state.

On the other hand, after the vehicle starts by engaging the electromagnetic powder clutch 2,
A line pressure control signal from the line pressure control unit 31 is manually input to the hydraulic control circuit 17, and the line pressure of the secondary cylinder 15a of the continuously variable transmission 4 applies a boob pressing force that prevents belt slip according to the transmitted torque etc. controlled as follows.

Further, the valve of the hydraulic control circuit 17 is operated by the shift control signal from the shift speed control section 30, and the primary pressure of the primary cylinder 14a is made variable. Therefore, depending on driving and running conditions, the belt 16 is shifted to one or the other of the bridle pulley pulley and the secondary pulley I5 depending on the driving and running conditions, and in this way, the power continuously variable by the continuously variable transmission 4 is transferred to the driving wheels 9. transmission, and the vehicle runs while changing gears optimally.

Regarding the case where the wheel locks due to brake operation on a low Fq friction road (low μ road) during the above-mentioned φ vehicle, in this case, the brake operation causes the wheel to lock as shown in Figures 5(b) and (e).
Vehicle speed V and engine speed Ne.

The primary pulley rotation speed Np suddenly decreased and the drive wheel 9
ABS operation starts when the T-lock is detected. Then, the flowchart shown in FIG. 4 is executed, and the clutch release determination section 40 makes a determination. That is, the engine rotation speed Ne or the set value N. If the brake pressure is higher, the clutch is held in the engaged state as shown in Figure 5(d), and even if the inertia mass of the continuously variable transmission primary system is large, the wheels can be easily rotated at a high engine speed when the brake pressure is reduced. If you don't hurry, you'll be left alone. Furthermore, if the brake is released under this condition, the brake will immediately return to its original state.

Next, after the ABS is activated, the engine speed Ne is a set value N higher than the lowest shift line Jl 1llin of the continuously variable transmission 4. When A is reached, a clutch release signal is output from the clutch */1' release determination unit 40 at this time t1, and A
The electromagnetic powder type clutch 2 is immediately released in the BS mode vehicle flow setting section 41. Therefore, from this point onwards, the engine speed N
e immediately becomes the idling quadrupling number N7. The continuously variable transmission 4 becomes independent of the engine 1 and changes the primary pulley rotation speed Np to the minimum shift line f4 based only on the wheel speed.
The speed is changed to be equal to the same rotation number Nmtn corresponding to win. Furthermore, since the engine 1 is disconnected, the inertial mass is reduced and the wheel speed can be smoothly restored when the ABS is activated. If you stop here, please stop at the 5th stop on the way.
The ABS is released as shown by the broken line in Figure (C), and at a predetermined vehicle speed, the clutch current in Figure 5(d) is changed to the drag current to shift to drag mode and return.

On the other hand, when accelerating by depressing the accelerator as shown in FIG. 5 ( ) while the ABS is in operation, the clutch engagement determining section 42 determines whether this is the case or not. In this case, as shown in FIG.
As shown in Fig. 5(d), when the clutch is released, the engine speed Ne increases as shown by the broken line in Fig. 5(b), and at time t2 when Ne≧No, the electromagnetic powder clutch 2 changes as shown in Fig. 5(d). Start engagement gently. In this way, as shown in Figure 5(b),
When Ne>Np, the electromagnetic powder clutch 2 is engaged, and unnecessary engine braking is no longer effective, and even if the vehicle is in continuously variable transmission*4 or a high speed gear, the vehicle can smoothly downshift and accelerate. Then, at a predetermined vehicle speed, the system shifts to direct connection mode and returns to its original state.

Although the embodiments of the present invention have been described above, the present invention is not limited thereto. Furthermore, it can be applied to both dry and wet multi-plate automatic clutches.

〔Effect of the invention〕

As described above, according to the present invention, in the control system of an automatic clutch combined with a continuously variable transmission, when ABS is activated, the engine speed is also taken into consideration when releasing and engaging, so that the engine braking effect is improved. This is preferable in terms of recovery, etc., and also prevents the engine from racing.

Furthermore, since the set engine speed for clutch disengagement and engagement is set higher than the lowest shift line of the continuously variable transmission, AB
Medium speed of the continuously variable transmission when S is activated.

Downshifting during acceleration can be performed for long hits.

[Brief explanation of drawings]

Figure 1 is a block diagram of an electronic control system showing an embodiment of an automatic clutch control device to which the present invention is applied, Figure 2 is an overall configuration diagram including the automatic clutch, and Figures 3 (a) and (b).
4 is a flowchart showing clutch control when ABS is activated. FIG. 5 is a time chart showing clutch control when ABS is activated.

Claims (3)

[Claims] (1) In a drive system that combines a continuously variable transmission with an automatic clutch, in a control system that automatically releases and engages the automatic clutch, the anti-lock braking system is activated during driving when the automatic clutch is engaged. Clutch release determination means for releasing the automatic clutch when the engine speed falls below a set value when an activation signal is input, and the anti-lock brake;
1. A control device for an automatic clutch for a vehicle, comprising: clutch engagement determining means for engaging the automatic clutch when the engine speed reaches a set value or more during acceleration during operation of the system. (2) Claim (1) characterized in that the set value of the engine speed is set higher than the lowest shift line of the continuously variable transmission.
A control device for the automatic clutch for a vehicle described above. (3) The control device for an automatic clutch for a vehicle according to claim (1), wherein the rise of the clutch torque when the automatic clutch is engaged is controlled to be gradual.