JPH045851B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a clutch control device for an automobile, especially one that automatically controls clutch engagement operation.
The present invention relates to a clutch control device that prevents harmful effects caused by being in a stall stop state for a long time when starting. Clutch control devices that automatically control the engagement and engagement of the clutch in accordance with the engine speed and the amount of depression of the accelerator pedal have already been put into practical use, and various improvements have been proposed. For example, according to JP-A-55-76224, it is possible to obtain a desired half-clutch state by engaging the clutch while comparing the amount of depression of the accelerator pedal, that is, the throttle opening, and the clutch stroke. An invention related to a "start control device for an automatic clutch operating device" is disclosed. However, in such an automatic clutch,
When starting by pressing down on the accelerator and brake pedals at the same time (so-called two-pedal starting or starting on a hill), the vehicle speed, that is, the output of the clutch, decreases even though the clutch is being engaged as the accelerator pedal is depressed or the engine speed increases. When the side rotational speed does not increase (at stall stop), the half-clutch state will be connected for a long time. Such a long-term half-clutch or stalled state causes an abnormal temperature increase in the clutch facing due to slippage, resulting in thermal damage and reduced durability of the clutch. By the way, in order to deal with the rise in temperature caused by clutch slipping, there is a device that measures the temperature of the clutch and issues an alarm when the temperature rises above a certain level, and a device that measures the temperature of the clutch and issues an alarm when the temperature rises above a certain level. A device is known that forcibly disconnects the However, the former device ignores the warning and may cause thermal damage to the clutch, and the latter device has the drawback that it is impossible to start with two pedals as described above. The present invention addresses the above-mentioned problems with automatic clutches, and automatically activates the clutch when the stall state continues for more than a certain period of time, such as when starting with two pedals or starting on a boarding road. Configure it to cut. As a result, the stall stop state is allowed within the above-mentioned certain period of time to enable two-pedal starting, etc., and the abnormal temperature rise of the clutch due to the stall stop state being connected after the certain period of time has elapsed, The purpose is to prevent thermal damage to the clutch. In particular, in the present invention, instead of uniformly setting the above-mentioned stall stop permission time, the time required to reach a certain clutch limit temperature is approximately inversely proportional to the energy absorbed per unit time by the clutch, as shown in Figure 1. Based on experimental results as shown, it is determined in each case by determining the absorbed energy of the clutch. As a result, the clutch is always released at the optimum timing when the stalled state continues, thereby effectively achieving the above object. That is, the present invention includes an actuator that operates a clutch engagement/disconnection operation member provided between an output shaft of an engine and an input shaft of a transmission, a discrimination circuit that detects the load state of the engine when the clutch is connected, and and a first control means for receiving the output of the discrimination circuit and controlling the actuator to limit the operation of the intermittent operation member in the clutch connection direction when the load increases due to the clutch connection. a timer means for detecting the energy absorbed by the clutch at and setting a permitted time until the clutch connecting operation is completed so that the larger the energy is, the shorter the permitted time is until the clutch connecting operation is completed within the set time of the timer means; and second control means for operating the actuator to release the connecting operation of the clutch when the clutch is opened. Hereinafter, the present invention will be explained based on embodiments shown in the drawings. As shown in FIG. 2, a clutch 3 is provided between the engine 1 and the transmission 2 to connect and disconnect power from the output shaft 1a of the engine 1 to the input shaft 2a of the transmission 2. The clutch 3 is configured to be connected when the lower end of the disconnecting operation member 4 moves to the left (direction A) in the drawing, and to be disconnected when the lower end moves to the right (direction B). A diaphragm actuator 6 for operating the operating member 4 via a rod 5 is provided. In this actuator 6, a negative pressure passage 8 led from the downstream side of the throttle valve 7 in the intake system 1b of the engine 1 is connected to a check valve 9 and a negative pressure tank 1 from the engine 1 side.
0 and a negative pressure control valve 11, and moves the operating member 4 in the clutch disengaging direction (direction B) when engine suction negative pressure is introduced. Also, the actuator 6 and the negative pressure control valve 1 in the negative pressure passage 8
1, an atmosphere introduction passage 13 in which an air control valve 12 is installed merges. A control circuit 14 is provided for outputting first and second opening/closing signals a and b to the negative pressure control valve 11 and the air control valve 12, respectively. An engine rotation signal c from an engine rotation sensor 15 that detects the rotation speed, and a vehicle speed sensor 16 that detects the rotation speed of the output shaft 2b of the transmission 2.
and the vehicle speed signal d from the clutch operating rod 5.
A clutch stroke signal e from a clutch stroke sensor 17 provided at An accelerator signal g is input. Here, the engine rotation signal c and vehicle speed signal d are input as pulse signals. Further, the neutral signal f and the accelerator signal g become "H" signals when the vehicle is in neutral and when the accelerator is depressed, respectively. Furthermore, the first and second opening/closing signals a and b are the control valve 1 corresponding to the "H" signal.
Open 1 and 12 respectively. Next, the configuration of the control circuit 14 will be explained with reference to FIG. The engine rotation signal c from the engine rotation sensor 15 indicating the rotational angular speed ωe of the engine 1 is converted into a voltage signal _c1 by the frequency-voltage converter 21 and then input to the differentiating circuit 22. It is taken as a signal C ₂ indicating the rate of change ω〓e, and
Furthermore, it is compared with the O voltage in the comparator 23, and ω〓e
It is converted into a signal _C3 which becomes an "H" signal when >O, and becomes an "L" signal when ω〓e<O. Further, the engine rotation signal C ₁ converted into the above voltage signal is input to the comparator 24 . In this comparator 24, a vehicle speed signal d from a vehicle speed sensor 16 indicating the vehicle speed V is converted into a voltage signal _d1 by a frequency-voltage converter 25, and a clutch rotational angular velocity ωc is further converted by a converter 26 into a voltage signal d1. It is input after being converted into the signal d ₂ shown in FIG.
Then, in the comparator 24, the engine rotation angular speed ωe indicated by the signal c ₁ and the clutch rotation angular velocity ωc indicated by the signal d ₂ are compared. ” signal h is output. This signal h and the comparator 2
The signal _c3 output from 3 is input to the XOR circuit 27, where the exclusive OR of both signals h and _c3 is calculated, and the switching between "H" and "L" is performed as shown in Table 1. A determination signal i to be performed is output.

[Table] In addition, the vehicle speed signal _d1 indicating the vehicle speed V converted into the above voltage signal is input to the comparator 28, and the first set vehicle speed (for example, 10 km/h) set in the comparator 28 is inputted to the comparator 28.
The signal d ₃ is compared with V ₁ and becomes an "H" signal when V>V ₁ . And with this signal d ₃ ,
When the accelerator signal g output from the accelerator switch 20 is inverted and input to the AND circuit 29, and both signals d ₃ and g are "L" signals, that is, the vehicle speed V is the first set vehicle speed V. ₁ or less and the accelerator is off, for example, a stop signal j that becomes an "H" signal when the vehicle is stopped is output. This stop signal j is passed through the OR circuit 30,
It is input to the negative pressure control valve 11 as the first opening/closing signal a. The first open/close signal a is inverted together with the discrimination signal i, and then sent to the AND circuit 31.
is input. Then, a second opening/closing signal b, which becomes an "H" signal when both signals a and i are "L" signals, is output to the air control valve 12. Also,
The above OR circuit 30 has a neutral switch 18.
A neutral signal f output from is input,
When the signal f is an "H" signal, that is, in a neutral state, a first opening/closing signal a of an "H" signal is output to the negative pressure control valve 11 and the AND circuit 31. The configuration of the control circuit 14 up to this point relates to the first control section that controls the clutch 3 according to the load condition of the engine 1. To summarize this, if the stop signal j or neutral signal f is "H"
In the case of a signal, the first opening/closing signal a becomes an "H" signal and the negative pressure control valve 11 opens. In this case, the second opening/closing signal b becomes the "L" signal, so that the air control valve 11 is always closed. On the other hand, when the first opening/closing signal a becomes an "L" signal and the negative pressure control valve 11 is closed, the second opening/closing signal b is switched or the air control valve 12 is switched by the discrimination signal i according to Table 1 above.
Opening/closing control is performed. Next, the second control section of the control circuit 14, that is, the control section for maintaining and canceling the stall stop state at the time of starting the vehicle will be explained. From the vehicle speed sensor 16 to the frequency-voltage converter 2
5 and the comparator 28, that is, the signal is "H" when the vehicle speed V is greater than the first set vehicle speed _V1 .
The signal _d3 , which is a signal, and the accelerator signal g, which becomes an "H" signal when the accelerator is turned on, which is output from the accelerator switch 20, are obtained by inverting only the former _d3.
The signal k is input to the AND circuit 32, and the circuit 32 outputs a signal k that becomes an "H" signal when the vehicle speed V is lower than the first set vehicle speed _V1 and the accelerator is on. Also,
The vehicle speed signal d ₁ converted into a voltage signal by the converter 25 is input to the comparator 33 . This comparator 33 compares the vehicle speed V with a second set vehicle speed V ₂ (for example, 2 km/h) which is smaller than the first set vehicle speed V ₁ , and outputs a signal d ₄ which becomes an "H" signal when V>V ₂ . Output. Then, this signal d ₄ and the above-mentioned signal k are inputted to the AND circuit 34 after only the former d ₄ is inverted, and the AND circuit 34 determines that the vehicle speed V is smaller than the second set vehicle speed V ₂ and that the accelerator is on. In other words, the stall signal l, which becomes an "H" signal when the stall stops, is input to the gate terminal of the counter 35, and as a result, the counter 35 starts counting the constant frequency pulse signal input from the oscillator 36. Further, the signal k and the signal _d4 are both input to the AND circuit 37 without being inverted, and from the AND circuit 37, it is determined that the vehicle speed V is below the first set vehicle speed _V1 and above the second set vehicle speed _V2 . and a reset signal m that becomes an “H” signal when the accelerator is on.
is output and input to the reset terminal of the counter 35 via the OR circuit 38. The OR circuit 3
8 or the reset terminal of the counter 35 are further connected to a signal d3 which becomes an "H" signal when the vehicle speed V is equal to or higher than the first set vehicle speed _V1 , and a signal _d3 which opens the negative pressure control valve 11 when the signal is "H". 1 open/close signal a is input as a reset signal. However, the control circuit 14 is further provided with a stall stop permission time setting circuit 39.
The engine rotation signal _c1 converted into a voltage signal by the frequency-voltage converter 21 and the clutch stroke signal e outputted from the clutch stroke sensor 17 are input. This clutch stroke signal e indicates the stroke amount of the clutch operation rod 5 shown in FIG.
The stroke amount of the rod 5 corresponds to the amount of engagement between the input member 3a and the output member 3b of the clutch 3, and this amount of engagement corresponds to the clutch transmission torque Tc. Furthermore, the engine rotational angular velocity ωe indicated by the engine rotational signal c ₁ is different from the input and output member 3 at the clutch 3 at the time of stall stop.
The slip speed between a and 3b is shown. Therefore, in the permission time setting circuit 39, these signals e,
The clutch absorbed energy per unit time (ωe×Tc) is determined based on c ₁ , and the stall stop permission time t ₀ is determined based on the relationship shown in the graph of Figure 1.
is required. Then, a signal n indicating this stall stop permission time t ₀ and a signal o indicating a count time (stall stop time) t from the input of the stall signal l outputted from the counter 35 are input to the comparison circuit 40. , both signals n and o are connected to the circuit 40
When the stall stop time t exceeds the stall stop permission time to, a time over signal p that becomes an "H" signal is output. This signal p is input to the alarm device 41, and when the signal is “H”, the alarm device 41
At the same time, the negative pressure control valve 11 and
It is input to the AND circuit 31. Next, the operation of the above embodiment will be explained with reference to the flowchart of FIG. First, when the transmission 2 shown in FIG. 2 is in neutral, that is, when changing gears while stopped or running, the neutral signal f or the first opening/closing signal a becomes an "H" signal, and the second opening/closing signal b becomes an "H" signal. "L"
As a signal, the negative pressure control valve 11 opens and the air control valve 12 closes. Therefore, engine intake negative pressure is introduced from the intake system 1b of the engine 1 to the actuator 6 through the negative pressure passage 8 and the negative pressure control valve 11, and the actuator 6 operates to cause the rod 5 to
The clutch 3 is then disconnected via the disconnection operation member 4 (FIG. 4, steps S ₁ and S ₃ ). At this time, the counter 35 is reset by the first opening/closing signal a (step S ₂ ). Furthermore, even if the transmission 2 is in a position other than neutral, when the vehicle speed V is lower than the first set vehicle speed V ₁ (for example, 10 km/h) and the accelerator is off, that is, when the vehicle is stopped or when it is decelerating, it is in a state immediately before stopping. etc., the stop signal j becomes an "H" signal, and the first opening/closing signal a becomes an "H" signal, thereby similarly opening the negative pressure control valve 11 and closing the air control valve 12. , the clutch 3 is disengaged (steps S ₁ , S ₄ , S ₅ , S ₂ , S ₃ ). On the other hand, when the transmission 2 is in a position other than neutral and the vehicle speed V is higher than the first set vehicle speed _V1 , both the neutral signal f and the stop signal j are "L" signals, and therefore the first opening/closing The signal a is also an "L" signal and the negative pressure control valve 11 is closed.
In this case, the opening and closing of the air control valve 12 is controlled by the discrimination signal i according to Table 1 (step S ₁ ,
_S4 , _S6 , _S7 ). In other words, when the relationship between the engine rotational angular speed ωe and the clutch rotational angular speed ωc and the rate of change ω〓e of the engine rotational angular speed are ωe>ωc and ω〓e>O, and when ωe<ωc and ω〓e<O. In other words, during normal acceleration or deceleration, the discrimination signal i is "L".
The input signals a and i of the AND circuit 31 are
When both become "L", the second opening/closing signal b
becomes an "H" signal, and the air control valve 12 opens. This allows the actuator 6 to enter the atmosphere introduction passage 13.
Atmosphere is introduced from the rod 5 and the intermittent operation member 4.
Clutch 3 is connected via (step S ₈ ).
Also, when ωe<ωc and ω〓e>O, that is, when the engine speed increases even though the engine brake is effective on a descending slope, and when ωe>ωc
In addition, when ω〓e<ωO, that is, when the accelerator pedal 19 is depressed, the load on the engine 1 increases due to an increase in the amount of engagement of the clutch 3, etc., and the engine rotation speed decreases. In this case, the discrimination signal i becomes an "H" signal and the second opening/closing signal b becomes an "L" signal.
The signal causes the air control valve 12 to close.
Therefore, in these cases, both the negative pressure control valve 11 and the air control valve 12 close, and the actuator 6
is closed and the clutch 3 is held in the currently engaged state (step _S9 ). As a result, if, for example, the rotational speed of the engine 1 decreases even though the accelerator pedal 19 is depressed, the increase in the amount of engagement of the clutch 3 is temporarily stopped, and the engine rotational speed increases again. If the above vehicle speed V is greater than the first set vehicle speed _V1 , the counter 35 is reset by the signal _d3 (step
_S6 ). However, when starting with two pedals, etc., even though the transmission 2 is in a position other than neutral and the accelerator is on, the vehicle speed V is less than the second set speed (for example, 2 km/h), that is, at a stall stop. In response to input of the stall signal 1, the counter 35 starts counting the stall time t (steps S ₁ , S ₄ , S ₅ , S ₁₀ , S ₁₁ ). On the other hand, the stall stop permission time setting circuit 39 receives signals c ₁ and e
The stall permission time to is set based on the engine rotational angular speed (clutch slip speed) ωe at that time indicated by and the stroke amount of the rod 5 (clutch transmission torque Tc) (step S ₁₂ ). and,
Until the stall time t reaches the allowable time to, the control from step _S13 to steps _S7 to _S8 is carried out to connect the clutch 3 or hold the clutch 3. but,
When the stall time t exceeds the allowable time to and the stall state continues, the comparison circuit 40 outputs a time over signal p and the first opening/closing signal a becomes an "H" signal, so that the negative pressure control valve 11 opens and Air control valve 12 is closed. As a result, the clutch 3 is disengaged and the stall stop condition is prevented from continuing beyond the above-mentioned allowable time to. At this time,
The alarm 41 is activated by the time-over signal p. When the vehicle speed V becomes greater than the second set vehicle speed _V2 immediately after the accelerator is turned on, control is performed from steps _S5 and _S10 to steps _S6 and _S7 , and the clutch 3 is connected or held. This control is carried out. Here, in order to accurately detect the stall stop state when starting with two pedals, the brake pedal 42 is equipped with a brake switch 43 as shown by the chain line in FIG. 2, and the brake signal q is controlled from the switch 43. It may also be input to the circuit 14. As described above, according to the present invention, in a clutch in which intermittent operation is automatically performed, a stall stop state is allowed up to a certain limit when starting with two pedals or starting on an uphill road, but the stall state continues beyond this limit. It is prevented from doing so. This prevents thermal damage and decreased durability due to abnormal temperature rise of the clutch.

[Brief explanation of drawings]

Fig. 1 is a graph showing the experimental results that are the basis of the control according to the present invention, Fig. 2 is a control system diagram showing an embodiment of the present invention, Fig. 3 is a control circuit diagram in the embodiment, and Fig. 4 is a diagram showing the control system according to the embodiment of the invention. FIG. 2 is a flowchart showing the operation of the embodiment. 1...Engine, 2...Transmission, 3...Clutch, 4
A control circuit including an intermittent operation member, 6 an actuator, and 14 a first control means and a second control means.

Claims (1)

[Claims] 1. An actuator that operates a clutch intermittent operation member provided between the output shaft of the engine and the input shaft of the transmission, a discrimination circuit that detects the load condition of the engine when the clutch is connected, and an output of the discrimination circuit. a first control means for controlling the actuator to limit the operation of the intermittent operation member in the direction of clutch connection when the load increases due to clutch engagement; and detecting energy absorbed by the clutch when the clutch is engaged; a timer means for setting a permitted time until the clutch connection operation is completed so that the timer means is large and almost short; A clutch control device for a motor vehicle, comprising a second control means for disengaging the clutch.