JPH0791467A - Control method for transmission - Google Patents

Abstract

PURPOSE:To improve durability of the whole of a device through sharing of a load generated by a clutch with main and auxiliary transmissions by a method wherein during a start, when the load of one clutch is increased, inclination of the gradual increase of the oil pressure of the clutch is increased. CONSTITUTION:During control of a start, completion of filling is confirmed by a controller 10 from the output of the filling detecting sensor 303 of a valve 34 connected to a main shift clutch 2nd and the gradual increase of an oil pressure on the valve 34 of the main shift clutch 2nd is started. In this case, during the gradual increase of the oil pressure of the main shift clutch 2nd, the calculating heating value Q of the main shift clutch is compared with a given threshold QC and when the heating value Q exceeds the threshold QC, at this point of time, the gradual increase factor dp/dt of the main shift clutch 2nd is increased to a value higher than a gradual increase factor followed thereby by the controller 10. On and after the gradual increase factor, the oil pressure of the main shift clutch is controlled with a gradually increased gradual increase factor. Thereafter, when engagement of the main shift clutch 2nd is completed, the oil pressure is held at a given oil pressure value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a transmission in a traveling machine, a construction machine or the like, and more particularly, in a transmission having a two-stage clutch composed of a main transmission and an auxiliary transmission, when starting at high power. The present invention relates to a method for reducing clutch heat load and improving clutch durability.

[0002]

2. Description of the Related Art A first-stage clutch (auxiliary transmission) on the input shaft side (torque converter side) of a transmission and a second-stage clutch (main transmission) on the output shaft side of the same transmission. In the transmission including, the speed stage is selected by the combination of the clutch on the auxiliary transmission side and the clutch on the main transmission side.

Conventionally, in this type of transmission, when starting or shifting, a predetermined hydraulic pressure is applied to both the main and sub shift clutches to control the shifting and starting. However, due to the structure of the transmission, the output is controlled. Since the main shift clutch on the shaft side is easily loaded, the heat load capacity of the main shift clutch side is designed to be larger than that of the auxiliary shift clutch side.

FIG. 15 shows a conventional general starting control. In this case, the 2nd starting operation is performed in which the 2nd clutch on the main transmission side is turned on and the Low clutch on the auxiliary transmission side is turned on ( N → F2) is assumed. Further, in this case, the gear shift of the low clutch on the auxiliary transmission side is started earlier than the gear shift of the second clutch on the main transmission side. In such a normal start as shown in FIG. 15, the shift lever is changed from N to D while the accelerator is loosened, so that the heat load on both the main and sub sides is small and the load is small as shown in FIG. 15 (f). There is little bias.

However, if the same 2nd start is performed without loosening the accelerator, as shown in FIG.
Excessive load (heat generation) concentrates on the d-clutch. In such a case, the clutch will be greatly damaged,
In some cases, the clutch may be destroyed even once. Further, in such high power start control, as shown in FIG.
As shown in (g), a large peak torque is generated at the end of the engagement, resulting in an uncomfortable starting shock.

Particularly, when the engagement is started with the hydraulic pressure in the low load mode at the time of high engine output, excessive heat generation occurs.

This is because in the conventional system, the shift control is performed while the load (heat generation amount) of the clutch is unknown. In the conventional control, the clutch engagement is determined by the hydraulic characteristics previously confirmed by the simulation or the actual vehicle test. Control is performed. However, in such a conventional system, an abnormal load is generated when the load changes abruptly or when there is an error in the hydraulic characteristics.

As another method, as shown in FIG. 17, the gradient of the hydraulic pressure on the auxiliary transmission side is made smaller than usual so that the auxiliary transmission is slowly engaged and the load is shared by the main and auxiliary transmissions. However, as shown in FIG. 17 (f), the effect is not so good.

The present invention has been made in view of the above circumstances, and provides a transmission control method for improving the durability of the entire transmission by sharing the load generated in the clutch by the main and auxiliary transmissions. With the goal.

[0010]

According to the present invention,
A transmission having a plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft and selecting a speed stage by a combination of the sub-shift clutch and the main shift clutch. , A transmission control method comprising: a plurality of pressure control valves that are individually connected to a plurality of clutches of the transmission and that generate hydraulic pressures corresponding to the input electric commands in the clutches. When the state quantity corresponding to the clutch load of one of the speed change clutch and the sub speed change clutch exceeds a predetermined prescribed value, the gradient of the hydraulic pressure gradual increase of this one clutch is increased.

According to this invention, when the load on one of the clutches increases at the time of starting, the engagement of the clutch is accelerated by increasing the inclination of the hydraulic pressure of the clutch to increase the load more than now. I try to prevent it.

Further, according to the present invention, a combination of the auxiliary shift clutch and the main shift clutch is provided which has a plurality of sub shift clutches at the first stage and a plurality of main shift clutches at the second stage from the transmission input shaft. Control of a transmission including a transmission that selects a speed stage with a plurality of clutches, and a plurality of pressure control valves that are individually connected to a plurality of clutches of the transmission and that generate hydraulic pressure corresponding to an input electric command in the clutches. In the method, when the state quantity corresponding to the clutch load of one of the main speed change clutch and the auxiliary speed change clutch exceeds a predetermined specified value when starting,
The hydraulic pressure of the other clutch is temporarily reduced to a low pressure value.

According to the present invention, when the load on one clutch becomes large at the time of starting, the hydraulic pressure of the other clutch is temporarily reduced so that the clutch on the side having the larger load is engaged earlier. , I try to prevent the load from increasing more than now.

Further, according to the present invention, the plurality of sub-shift clutches at the first stage from the transmission input shaft and the second sub-shift clutch are provided.
A transmission having a plurality of main shift clutches at a stage and selecting a speed stage by a combination of an auxiliary shift clutch and a main shift clutch, and a plurality of clutches of this transmission are individually connected and input. In a control method of a transmission including a plurality of pressure control valves for generating a hydraulic pressure corresponding to an electric command in the clutch, when starting,
When the filling of both the main speed change clutch and the auxiliary speed change clutch is completed, the difference between the relative speed of the auxiliary speed change clutch and the relative speed of the main speed change clutch is maintained so as to maintain a predetermined value. The hydraulic pressure of one of the clutches is controlled.

According to this invention, since the relative rotational speed of the auxiliary transmission clutch and the relative rotational speed of the main transmission clutch are controlled so as to maintain a constant rotational speed difference, the load is preferably shared by the main and auxiliary transmissions. To be done.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the accompanying drawings.

FIG. 3 shows a transmission system to which the present invention is applied.

In FIG. 3, the output of the engine 1 is transmitted to the transmission 3 via the torque converter (torque converter) 2, and the output of the transmission 3 is transmitted to the drive wheels 5 via the differential gear and the final reduction gear 4. . A lockup clutch 6 that directly connects the input and output shafts of the torque converter 2 is interposed.

The engine 1 is provided with an engine rotation sensor 7 which outputs a signal of a number corresponding to the rotational speed n1, and the transmission 3 is provided with the rotational speeds n2, n3 and n4 of its input shaft, intermediate shaft and output shaft. Rotation sensors 8, 9 and 15 for outputting the same number of signals are respectively provided, and the outputs of these sensors are added to the controller 10.

The throttle amount sensor 11 detects the depression amount of the throttle pedal and inputs a signal S indicating the depression amount to the controller 10. The vehicle weight sensor 12 detects the vehicle weight I (load weight) and inputs the detected value to the controller 10. The shift selector 13 inputs a signal indicating the shift position (R, N, D, 1 ...) Selected by the shift lever 14 to the controller 10.

The transmission 3 is a first-stage auxiliary transmission clutch H (Hi) connected to the output shaft of the torque converter 2.
gh) and L (Low) and second-stage main transmission clutches 1st and 2nd connected to the output shaft of the transmission 3, and clutches H and L on the auxiliary transmission side and clutches 1st and 2nd on the main transmission side. In combination with the speed stage (L1: 1st speed,
(H1: 2nd speed, L2: 3rd speed, H2: 4th speed).

The clutch pressure oil supply device 20 for supplying pressure oil to these clutches is, as shown in FIG.
1. In addition to the relief valve 22, the clutches H, L,
Clutch hydraulic pressure control valves 31, 32, 33 and 34 for applying hydraulic pressure to the 1st and 2nd are provided separately for each clutch. The lockup clutch 6 is also an electronic pressure proportional control valve 35 that applies hydraulic pressure to the clutch.
The valves 31 to 35 are independently operated by an electric command from the controller 10.

FIG. 5 shows the clutch hydraulic pressure control valve 31.
To 34, the clutch hydraulic pressure control valves 31 to 34 respectively include a pressure control valve 301 for controlling the clutch hydraulic pressure and a flow rate detection valve 30 as shown in FIG.
2 and a sensor unit 303 for detecting the end of filling. The pressure control valve 301 is controlled by the controller 10, and the detection signal of the sensor unit 303 is input to the controller 10.

The clutch hydraulic pressure control valves 31 to 34 flow in the oil from the pump 21 via the input port 310 and supply the oil to the clutch via the output port 311. Port 312 is closed and ports 313, 31
4 is a drain port.

The electronic pressure control valve 301 has a spool 315.
The right end of this spool 315 has a proportional solenoid 3
16 plunger 317 and a spring 31 at the left end.
8 are provided. Spool 315 and piston 319
The oil pressure in the oil passage 322 is fed back to the oil chamber 320 defined by the above through an oil passage 321 formed in the spool 315.

The flow rate detection valve 302 has a spool 325, and the spool 325 defines oil chambers 326, 327 and 328. The oil chamber 32 of this spool 325
An orifice 330 is formed between 7,328. The spool 325 is configured to have three different pressure receiving areas A1, A2, and A3, with A1 + between these areas.
The relations of A3> A2 and A2> A3 are given. The spring 331 is at the left end of the spool 325, and the spring 3 is at the right end.
32 is provided, and this spool 325 is an oil chamber 32.
When the pressure is not applied to 7,328, the neutral position shown in FIG. 5 is held at the positions of the free lengths of the springs 331 and 332. That is, in this case, the spring 33
1 acts as a return spring for the spool 325, and the spring 332 acts as a pressure setting spring for detecting the clutch oil pressure.

A detection pin 334 made of metal is provided on the upper right side of the valve body 333, and by this detection pin 334, the spool 325 resists the spring force of the spring 332 and moves further to the right from the neutral position shown in FIG. Detect that you have moved. This detection pin 334 is covered with an insulating sheet 3 by a cover 335.
It is attached to the body 333 via 36, and a lead wire 337 is drawn out from this detection pin 334.

The lead wire 337 is connected to the point a between the resistors R1 and R2 connected in series. These resistance R
A predetermined DC voltage V (for example, 12V) is applied between 1 and R2, and the body 333 is grounded.

The operation of the valves 31 to 34 having the above construction will be described with reference to the time chart of FIG.

In FIG. 6, (a) is the controller 1
The command current I from 0, (b) shows the oil pressure (clutch pressure) of the oil chamber 328, and (c) shows the output of the sensor 303.

When attempting to engage the clutch, the controller 10 inputs a trigger command to the solenoid 316 of the corresponding clutch hydraulic pressure control valve, and then the command current I is applied to a predetermined initial pressure command corresponding to the clutch hydraulic pressure initial pressure. The current is dropped, and in this state, it waits until the end of filling (see FIG. 6 (a)).

By the input of the trigger command, the spool 315 of the pressure control valve 301 moves to the left, and the oil from the pump passes through the input port 310 and the oil passage 322 to the oil chamber of the flow rate detection valve 302. Flows into 327. The oil that has entered the oil chamber 327 flows into the oil chamber 328 through the orifice 330,
It flows into the clutch via the output port 311. At this time, the orifice 330 generates a pressure difference between the oil chambers 327 and 328, so that the spool 325 moves to the left.

As a result, the flow rate detection valve 302 is opened,
The oil from the pump that has flowed into the oil passage 329 flows into the oil chamber 327 through the oil chamber 326, and then the orifice 330,
It flows into the clutch through the oil chamber 328 and the output port 311. This oil flow continues until the clutch pack is filled with oil.

Here, when the spool 325 is in the neutral position shown in FIG. 5 and during the filling time tf during which the spool 325 is moving to the left of the neutral position, the spool 325 is used. Is separated from the detection pin 334.

Therefore, in this state, the potential at the point a has a voltage value obtained by dividing the voltage V by the resistors R1 and R2 as shown in FIG. 6 (c).

When the clutch pack is filled with oil, the filling is completed and the oil no longer flows, so there is no differential pressure before and after the orifice 330.

Therefore, the spool 325 has the spring 331.
To the restoring force of the spool 325 (A1 + A3-A)
2) Move to the right with the force added by the force.

When the spool 325 is returned, the hydraulic pressure from the pump is applied to the oil passage 329, the oil chamber 327, and the orifice 33.
0, the oil pressure is applied to the clutch via the oil chamber 328, and as a result, the overshoot pressure as shown in FIG. 6B is generated.

The spring constant of the spring 332 is shown in FIG.
As shown in (b), the pressure value Th is set to be smaller than the overshoot pressure.

Therefore, at the time of this return operation, the spool 32
5 goes right to the neutral position shown in FIG.
The right pressure surface overcomes the biasing force of the spring 332 and moves further to the right, and its right end surface contacts the detection pin 334.

As a result, the detection pin 334 is connected to the spool 32.
Since it is electrically connected to the body 333 grounded via 5, the potential at point a drops to zero as shown in FIG. 6 (c), and no voltage appears at point a.

The potential at the point a is input to the controller 10, and the controller 10 determines the end of filling at the fall of the potential at the point a. When it is determined that the filling is completed, the controller 10 immediately gradually increases the command current I for the clutch from the initial pressure command current value (FIG. 6 (a)).

As a result, the clutch pressure of the clutch drops from the overshoot pressure value to the initial pressure as shown in FIG. 6B, and then gradually increases. Therefore, the spool 325 temporarily moves leftward from the state of being in contact with the pin 334 toward the neutral position. After that, the clutch pressure is gradually increased and exceeds the set pressure Th of the spring 332 at a certain point. As a result, the spool 325 overcomes the biasing force of the spring 332 and moves to the right again, and its right end face contacts the detection pin 334. Therefore, the potential at the point a drops to zero again, and thereafter maintains this zero level.

That is, the potential at the point a is set to the clutch by the set pressure T
When the pressure over h is zero, it becomes zero, and when the clutch pressure is below the set pressure Th, it becomes a predetermined voltage value. Therefore, the controller 10 not only detects the filling end by monitoring the potential at the point a, but also the clutch. It is possible to know the presence or absence of pressure, that is, the engagement state of the clutch.

The present device calculates the load of the clutch at the time of starting in real time and reflects the result in the clutch hydraulic pressure to avoid an abnormal load at the time of starting. Detailed description thereof will be given. Before the above, a method of calculating the clutch heat generation amount Q will be described.

The clutch heat generation rate q is the clutch torque Tc.
Is proportional to the product of the clutch relative rotation speed ωc and is expressed by the following equation (1).

Q = Tcωc (1) Tc: Clutch torque ωc: Relative rotational speed of the clutch Further, the clutch heat generation amount Q is a time integration of the clutch heat generation rate q and is expressed by the following equation.

[0048] Further, the clutch heat load E is obtained by the following equation.

E = Q · qmax (3) qmax: clutch maximum heat generation rate Here, the clutch torque Tc is proportional to the clutch friction coefficient μ, the clutch hydraulic pressure P, and other coefficients, and is expressed by the following equation. Tc = μ · P · A · Rm · N (5) A: Piston area Rm: Effective average radius N: Number of clutches In the above formula (5), A: Piston area, Rm: Effective average radius, N: Number of clutches Are respectively constant values, the friction coefficient μ and the clutch hydraulic pressure P may be known in order to calculate the clutch torque Tc. Further, in order to calculate the clutch heat generation rate q, it suffices to know the clutch relative rotational speed ωc.

That is, if the friction coefficient μ, the clutch oil pressure P and the clutch relative rotational speed ωc are known, the clutch heat load (clutch heat generation amount) can be obtained.

Here, the clutch oil pressure P can be calculated by the current command I input from the controller 10 to the pressure control valve 301, or can be directly detected by a sensor.

The coefficient of friction μ is determined by the sensors 8, 9, 15
It can be calculated using the shaft rotation speed and the gear ratio obtained from the above.

Further, the clutch relative rotation speed ωc can be calculated by using the outputs of the rotation sensors 8, 9, 15 provided in the transmission 3.

Therefore, the friction coefficient μ, the clutch oil pressure P, and the clutch relative rotation speed ωc obtained as described above.
The clutch heat generation amount Q can be calculated by substituting the above into the equations (5), (1), and (2).

Next, the controller 1 in such a configuration
A first embodiment of zero start control will be described with reference to the flowchart of FIG. 1 and the time chart of FIG.

When starting (step 100), the controller 10 first supplies pressure oil to the clutch oil pressure control valve 32 connected to the auxiliary transmission clutch (in this case, Low clutch) to be engaged. It starts (step 110, time t0 in FIG. 2).

At this time, the controller 10 causes the solenoid of the clutch hydraulic pressure control valve 32 of the clutch Low to be engaged to the command value pattern as described in FIG. 6 (a).
Add This command value pattern is shown in Fig. 2 (c).
As shown in, the high clutch pressure is applied to the clutch to speed up the end of filling, and the command pressure is lowered to a low level before the end of filling thereafter. Is kept low to prevent shift shock.

Next, the controller 10 confirms the completion of the filling from the output of the filling detection sensor 303 provided in the valve 32 connected to the auxiliary shift clutch Low (step 120), and the sensor 303 performs the above-mentioned filling. When the end detection signal is input (time t1 in FIG. 2)
Therefore, the hydraulic pressure of the auxiliary transmission clutch Low is gradually increased with an appropriate inclination (step 130).

At the time t1 at which the filling is completed, pressure oil supply is started to the clutch hydraulic pressure control valve 34 connected to the main shift clutch (in this case, 2nd) (step 130). At this time, the controller 10 applies a command value pattern similar to that of the sub speed change clutch Low to the solenoid of the clutch hydraulic pressure control valve 34 of the main speed change clutch 2nd.

Next, the controller 10 confirms the end of the filling from the output of the filling detection sensor 303 of the valve 34 connected to the main speed change clutch 2nd (step 140), and detects the above-mentioned filling end from this sensor 303. At the time when the signal is input (time t2 in FIG. 2), the following two controls are executed (step 150).

(A) Start the gradual increase of the hydraulic pressure to the valve 34 of the main speed change clutch 2nd (b) Calculate the heat generation amount Q of the main speed change clutch by the method described above. This calculation is continued in real time thereafter.

The controller 10 calculates the calorific value Q of the main shift clutch calculated while the hydraulic pressure of the main shift clutch 2nd is gradually increased.
Is compared with a predetermined threshold value Qc (set 30% to 40% lower than the Q limit value) (step 160), and the threshold value Qc is maintained until the amount of heat generation Q ends engagement of the main speed change clutch 2nd.
If it does not exceed, the hydraulic pressure of the main speed change clutch 2nd is gradually increased at the same gradual increase rate. When the engagement of the main shift clutch 2nd is completed, the hydraulic pressure of the main shift clutch 2nd is maintained at a predetermined hydraulic pressure value (steps 180, 190).

However, when the heat generation amount Q of the main transmission clutch exceeds the threshold value Qc during the gradual increase of the hydraulic pressure (step 1)
60) At this time t3, the controller 10 increases the gradual increase rate dP / dt of the main transmission clutch 2nd more than the gradual increase rate before this (see step 170 in FIG. 2 (a)). After that, the main shift clutch hydraulic pressure is controlled at the gradually increasing rate. After that, when the engagement of the main shift clutch 2nd is finished, the hydraulic pressure of the main shift clutch 2nd is maintained at a predetermined hydraulic pressure value (steps 180, 190).

That is, in this first embodiment,
If the amount of heat generated by the main speed change clutch exceeds a predetermined threshold during start control, the increase in the hydraulic pressure of the main speed change clutch is increased to reduce the increase in the load on the main speed change clutch thereafter, and the main transmission is engaged. By so doing, it is possible to prevent the load from being concentrated on the clutch (main transmission) on one side, and to appropriately perform load sharing in the main and auxiliary transmissions. Incidentally, FIG. 2 (f) shows that the load is well shared by the main transmission and the auxiliary transmission.

In the above embodiment, the clutch load is detected by the clutch heat generation amount Q, but the clutch load can be estimated by the clutch plate temperature T, for example.

That is, the clutch plate temperature Tcl is
It has the following relationship.

[0067] Tb: Lubricating oil temperature Kh: Temperature conversion coefficient Kc: Heat dissipation coefficient The second term on the right side of the above equation (6) is the heat generated by the clutch, and the third term is the heat released by the clutch. The clutch heat generation amount of the second term can be obtained according to the above equations (1) to (5). Further, the first and third terms can be calculated if the lubricating oil temperature and the heat radiation coefficient Kc can be obtained.

The lubricating oil temperature is detected by disposing a lubricating oil temperature sensor in the clutch. The heat dissipation coefficient Kc is
Since it is known by knowing the clutch engagement / disengagement state and the cooling oil amount, these are detected from the outputs of the shift selector 13 and the engine rotation sensor 7, respectively, and these detected values are input to the memory map in which the heat radiation coefficient Kc is stored. The heat dissipation coefficient Kc is determined by the fact.

Further, in the above embodiment, the shift is started on the auxiliary transmission side before the main transmission side. However, the shift on the main transmission side is started before the sub transmission side. Good.

Next, a second embodiment of the present invention will be described with reference to the flowchart of FIG. 7 and the time chart of FIG.

In this second embodiment, step 200
The procedure from step 260 to step 260 is the same as the procedure from step 100 to step 160 of the first embodiment shown in FIG. 1 above, and a duplicated description will be omitted.

In the second embodiment, after the hydraulic pressure of the auxiliary transmission clutch Low is gradually increased, the heat generation amount Q of the main transmission clutch 2nd is determined by the determination in step 260 until the hydraulic pressure of the auxiliary transmission clutch Low reaches a predetermined hydraulic pressure value P2. If the threshold value Qc is not exceeded, no special control is performed. Then, when the oil pressure of the auxiliary shift clutch reaches a predetermined oil pressure value P2, this oil pressure is maintained (steps 261 and 262).

However, when the heat generation amount Q of the main transmission clutch 2nd exceeds the predetermined threshold value Qc in the determination of step 260 during the gradual increase of the hydraulic pressure of the main transmission clutch 2nd, the hydraulic pressure of the auxiliary transmission clutch Low is set to the predetermined value at this time t3. To the low pressure value P1 (step 270, time t3 in FIGS. 8 (c) (d)), and in this state, the process waits until it is confirmed that the main transmission clutch 2nd has been engaged. When the completion of the engagement of the main shift clutch 2nd is confirmed by the output of the sensor 303 or the detection of the clutch relative rotation speed (step 280, FIG. 8 (c) (d) (e) time t4), the sub shift is performed. The hydraulic pressure of the auxiliary transmission clutch Low is raised to a predetermined hydraulic pressure value to rapidly engage the clutch Low, and the hydraulic pressure is gradually increased from the raised hydraulic pressure value (step 290). Then, when the hydraulic pressure of the auxiliary shift clutch reaches a predetermined hydraulic pressure value P2 thereafter, this hydraulic pressure is maintained (steps 261 and 262). If the startup hydraulic pressure value at time t4 is set to an output torque equivalent to that at the end of engagement of the clutch on the main shift side, shift shock can be reduced.

That is, in the second embodiment, when the amount of heat generated by the main transmission clutch exceeds a predetermined threshold during start control, the hydraulic pressure of the auxiliary transmission clutch is reduced to accelerate engagement of the main transmission clutch. The load of the main transmission clutch is prevented from further increasing, and the auxiliary transmission clutch having a sufficient load capacity is allowed to share the load. Therefore, according to the second embodiment, the load is prevented from being concentrated on the clutch (main transmission) on one side, and the load is suitably shared in the main and auxiliary transmissions. By the way, Fig. 8
In (f), it is apparent that the load is well shared by the main transmission and the auxiliary transmission. The control according to the second embodiment also has the secondary effect of reducing the peak torque of the output shaft torque and reducing the starting shock, as shown in FIG. 8 (g).

It is also possible to perform control by combining the first and second embodiments. That is, the clutch heat generation amount Q
Is greater than the threshold value Qc, the gradient of the increase in hydraulic pressure on the main transmission side is gradually increased, and the hydraulic pressure on the auxiliary transmission side is temporarily reduced to a low pressure value.

Next, a third embodiment of the present invention will be described with reference to FIG.
This will be described with reference to the flowchart of FIG.

In the third embodiment, the order of the clutches for starting the shift is opposite to that of the first or second embodiment, the engagement control of the main transmission is started first, and then the auxiliary transmission is started. It is assumed that the engagement control is performed.

First, when starting the vehicle (step 300), the controller 10 first applies pressure oil to the clutch oil pressure control valve 32 connected to the main transmission clutch (the second clutch in this case) to be engaged. Supply is started (step 310, time t0 in FIG. 10).

Next, the controller 10 confirms the completion of filling from the output of the filling detection sensor 303 provided in the valve 32 connected to the main speed change clutch 2nd (step 320), and the sensor 303 performs the above-mentioned filling. When the end detection signal is input (time t in FIG. 10)
From 1), the hydraulic pressure of the main transmission clutch 2nd is gradually increased with an appropriate inclination (step 330). Then, from this time point, the heat generation amount Q of the main shift clutch is calculated by the above-described method.
This calculation is continued in real time thereafter.

At the time t1 at which the filling is completed, pressure oil supply to the clutch hydraulic pressure control valve 34 connected to the auxiliary transmission clutch (Low in this case) is started (step 330).

Next, the controller 10 confirms the end of filling from the output of the filling detection sensor 303 of the valve 34 connected to the auxiliary transmission clutch Low (step 340), and detects the above-mentioned filling end from this sensor 303. At the time when the signal is input (time t2 in FIG. 10), the hydraulic pressure to the valve 34 of the auxiliary transmission clutch Low is gradually increased (step 350).

The controller 10 compares the calculated heat generation amount Q of the main transmission clutch with a predetermined threshold value Qc during the gradual increase of the hydraulic pressure of the main transmission clutch 2nd and the auxiliary transmission clutch Low (step 360). After the hydraulic pressure of gradually increasing, the special control is performed if the calorific value Q of the main speed change clutch 2nd does not exceed the predetermined threshold value Qc in the determination of step 360 until the hydraulic pressure of the sub speed change clutch Low reaches the predetermined hydraulic pressure value P2. Not performed. Then, when the hydraulic pressure of the auxiliary shift clutch Low reaches a predetermined hydraulic pressure value P2, this hydraulic pressure is maintained (steps 361 and 362).

However, if the calorific value Q of the main transmission clutch 2nd exceeds the predetermined threshold value Qc in the determination of step 360 during the gradual increase of the hydraulic pressure of the auxiliary transmission clutch 2nd, the hydraulic pressure of the auxiliary transmission clutch Low is set to a predetermined value at this time t3. To the low pressure value P1 (step 370, time t3 in FIGS. 10 (c) (d)), and in this state, the process waits until it is confirmed that the main transmission clutch 2nd is engaged. Then, when the completion of the engagement of the main shift clutch 2nd is confirmed by the output of the sensor 303 or the detection of the clutch relative rotation speed (step 380, FIG. 10 (c) (d)).
(e) At time t4), the hydraulic pressure of the auxiliary transmission clutch Low is raised to a predetermined hydraulic pressure value in order to rapidly engage the auxiliary transmission clutch Low, and the hydraulic pressure is gradually increased from the raised hydraulic pressure value (step 390). . After that, when the hydraulic pressure of the auxiliary shift clutch reaches a predetermined hydraulic pressure value P2, this hydraulic pressure is maintained (steps 361 and 362).

That is, in the third embodiment, the order of the clutches for starting the gear shift is opposite to that of the previous embodiment, but the other parts are the same as those of the second embodiment and the main control is performed during the start control. When the amount of heat generated by the speed change clutch exceeds a predetermined threshold value, the hydraulic pressure of the auxiliary speed change clutch is reduced to speed up the engagement of the main speed change clutch to prevent the load of the main speed change clutch from increasing any more. The auxiliary shift clutch, which has sufficient capacity, is responsible for that.

In the second and third embodiments described above,
The clutch load may be grasped by the clutch plate temperature.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
This will be described with reference to the flowchart of FIG. 1 and the time chart of FIG.

When starting (step 400), the controller 10 first supplies pressure oil to the clutch oil pressure control valve 32 connected to the auxiliary transmission clutch (in this case, Low clutch) to be engaged. Is started (step 405, time t0 in FIG. 12).

Next, the controller 10 confirms the completion of the filling from the output of the filling detection sensor 303 provided on the valve 32 connected to the auxiliary shift clutch Low (step 410), and the sensor 303 performs the above-mentioned filling. When the end detection signal is input (time t in FIG. 12)
From 1), the hydraulic pressure of the auxiliary transmission clutch Low is maintained at a predetermined low pressure value (step 415).

At the time t1 at which the filling is completed, pressure oil supply to the clutch hydraulic pressure control valve 34 connected to the main speed change clutch (2nd in this case) is started (step 415). At this time, the controller 10 applies a command value pattern similar to that of the sub speed change clutch Low to the solenoid of the clutch hydraulic pressure control valve 34 of the main speed change clutch 2nd.

Next, the controller 10 confirms the end of filling from the output of the filling detection sensor 303 of the valve 34 connected to the main speed change clutch 2nd (step 420), and detects the above-mentioned filling end from this sensor 303. At the time when the signal is input (time t2 in FIG. 12), the hydraulic pressure to the valve 34 of the main transmission clutch 2nd is gradually increased (step 425).

Next, the controller 10 executes the following control for the auxiliary transmission side (Low clutch in this case) until the engagement of the main transmission side clutch (2nd clutch in this case) is completed.

That is, the relative rotational speed ωlow on the auxiliary transmission side
Is compared with a value (ω2nd + α) obtained by adding an arbitrary rotation speed α to the relative speed ω2nd on the main transmission side (step 430),
The following control is executed.

(A) When ωlow <ω2nd + α, the hydraulic pressure on the auxiliary transmission side is decreased at a predetermined hydraulic pressure gradient. However, when the pressure is lower than the minimum pressure, the minimum pressure is maintained (step 435).

(B) When ωlow = ω2nd + α, the hydraulic pressure on the auxiliary transmission side is kept at that value (step 44).
0).

(C) When ωlow> ω2nd + α, the hydraulic pressure on the auxiliary transmission side is increased at a predetermined hydraulic pressure gradient. However, if the maximum pressure is exceeded, the maximum pressure is maintained (step 445).

That is, in the above control, the difference between the relative rotation speed on the side of the auxiliary transmission and the relative rotation speed on the side of the main transmission is controlled to always be a constant value α. It is possible to appropriately share the load.

After that, the controller 10 determines whether or not the engagement of the main transmission clutch 2nd is completed (step 45).
0), when it is determined that the engagement is completed (time t3), the hydraulic pressure of the auxiliary shift clutch is gradually increased at a predetermined gradient (step 45).
5).

Further, thereafter, the controller 10 determines whether or not the engagement of the auxiliary transmission clutch Low is completed (step 460), and when the completion of engagement is determined (time t4), the hydraulic pressure of the auxiliary transmission clutch is steeply increased. The gradient is gradually increased to converge to the specified pressure (step 465).

Next, a fifth embodiment of the present invention will be described with reference to FIG.
This will be described with reference to the flowchart of FIG. 3 and the time chart of FIG.

In the fifth embodiment, the order of shifting clutches is opposite to that in the fourth embodiment, the engagement control of the main transmission is started first, and thereafter the engagement of the sub-transmission is engaged. It is assumed that control will be performed.

First, when starting the vehicle (step 500), the controller 10 applies pressure oil to the clutch oil pressure control valve 32 connected to the main transmission clutch (the second clutch in this case) to be engaged first. The supply is started (step 505, time t0 in FIG. 14).

Next, the controller 10 confirms the completion of filling from the output of the filling detection sensor 303 provided in the valve 32 connected to the main speed change clutch 2nd (step 510), and the sensor 303 performs the above-mentioned filling operation. The time when the end detection signal is input (time t in FIG. 14).
From 1), the hydraulic pressure of the main transmission clutch 2nd is gradually increased with an appropriate inclination (step 515).

At the time t1 at which the filling is completed, pressure oil supply to the clutch hydraulic pressure control valve 34 connected to the auxiliary transmission clutch (Low in this case) is started (step 515).

Next, the controller 10 confirms the completion of filling from the output of the filling detection sensor 303 of the valve 34 connected to the auxiliary transmission clutch Low (step 520, time t2 in FIG. 14).

Next, as in the case of the fourth embodiment, the controller 10 controls the auxiliary transmission side (Low clutch in this case) as follows by the main transmission side (2nd clutch in this case).
It is executed until the engagement of the clutch is completed.

That is, the relative rotational speed ωlow on the auxiliary transmission side
Is compared with a value (ω2nd + α) obtained by adding an arbitrary rotation speed α to the relative rotation speed ω2nd on the main transmission side (step 525),
The following control is executed.

(A) When ωlow <ω2nd + α, the hydraulic pressure on the auxiliary transmission side is decreased with a predetermined hydraulic pressure gradient. However, when the pressure is lower than the minimum pressure, the minimum pressure is maintained (step 530).

(B) When ωlow = ω2nd + α, the hydraulic pressure on the auxiliary transmission side is kept at that value (step 53).
5).

(C) When ωlow> ω2nd + α, the hydraulic pressure on the auxiliary transmission side is increased at a predetermined hydraulic pressure gradient. However, if the maximum pressure is exceeded, the maximum pressure is maintained (step 540).

Thereafter, the controller 10 determines whether the engagement of the main speed change clutch 2nd is completed (step 54).
5) When it is determined that the engagement is completed (time t3), the hydraulic pressure of the auxiliary transmission clutch is controlled to be gradually increased at a predetermined gradient (step 55).
0).

Further, thereafter, the controller 10 determines whether or not the engagement of the auxiliary transmission clutch Low has ended (step 555), and when it determines that the engagement has ended (time t4), the hydraulic pressure of the auxiliary transmission clutch steeply increases. The gradient is gradually increased to reach the specified pressure (step 560).

In the above embodiment, the hydraulic pressure on the auxiliary transmission side is controlled so that the relative rotational speed on the main transmission side and the relative rotational speed on the auxiliary transmission side become the predetermined rotational speed difference α. The hydraulic pressure on the main transmission side may be controlled so that the rotation speed difference α is obtained.

In each of the above embodiments, the case of starting is shown, but the same control can be applied during shifting.

Further, in the above embodiment, the filling detection sensor 303 having the structure shown in FIG. 5 is used to detect the end of the filling. However, a filling detection sensor having another structure may be used. A time management method of setting an appropriate filling time may be used.

The present invention can be applied to both a manual transmission and an automatic transmission. Further, in the above embodiment, the present invention is applied to a transmission having two auxiliary transmissions H and L at the first stage and two main transmissions 1st and 2nd at the second stage. However, other types of transmissions, such as (main; H, L. sub; 1, 2, 3, 4, R) or (main; F, R. sub; 1, 2, 3, 4), etc. Of course, the present invention is also applicable.

[0116]

As described above, according to the present invention,
The clutch load at the time of starting can be appropriately shared by the main and auxiliary transmissions, and shift shock can be reliably prevented.

[Brief description of drawings]

FIG. 1 is a flow chart showing a first embodiment of the present invention.

FIG. 2 is a time chart for explaining a specific operation example of the first embodiment.

FIG. 3 is a block diagram showing an example of the overall configuration of a transmission system.

FIG. 4 is a hydraulic circuit diagram showing an internal configuration of a clutch hydraulic pressure supply device of the transmission system.

FIG. 5 is a sectional view showing an internal configuration of a clutch hydraulic pressure control valve.

FIG. 6 is a time chart for explaining the operation of the clutch hydraulic control valve.

FIG. 7 is a flowchart showing a second embodiment of the present invention.

FIG. 8 is a time chart for explaining a specific operation example of the second embodiment.

FIG. 9 is a flowchart showing a third embodiment of the present invention.

FIG. 10 is a time chart for explaining a specific operation example of the third embodiment.

FIG. 11 is a flow chart showing a fourth embodiment of the present invention.
To.

FIG. 12 is a time chart for explaining a specific operation example of the fourth embodiment.

FIG. 13 is a flowchart showing a fifth embodiment of the present invention.
To.

FIG. 14 is a time chart for explaining a specific operation example of the fifth embodiment.

FIG. 15 is a time chart illustrating a conventional technique.

FIG. 16 is a time chart explaining a conventional technique.

FIG. 17 is a time chart explaining a conventional technique.

[Explanation of symbols]

 1 ... Engine 2 ... Torque converter 3 ... Transmission 6 ... Lockup clutch 7, 8, 9 ... Rotation speed sensor 10 ... Controller 11 ... Throttle amount sensor 12 ... Vehicle weight sensor 13 ... Shift selector 1st, 2nd ... Main shift Machines H, L ... Auxiliary transmission 301 ... Flow rate control valve 302 ... Flow rate detection valve 303 ... Filling end detection sensor

Claims (13)

[Claims] 1. A speed stage having a plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft and a combination of the sub-shift clutch and the main shift clutch. Transmission to choose
A control method for a transmission, comprising: a plurality of pressure control valves that are individually connected to a plurality of clutches of this transmission and that generate hydraulic pressures corresponding to the input electric commands in the clutches. When the state quantity corresponding to the clutch load of one of the clutch and the auxiliary shift clutch exceeds a predetermined prescribed value, the gradient of the hydraulic pressure gradual increase of this one clutch is increased. Method. 2. A plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft, wherein a speed is obtained by combining the sub-shift clutch and the main shift clutch. A transmission control method comprising: a transmission that selects a stage; and a plurality of pressure control valves that are individually connected to a plurality of clutches of the transmission and that cause a hydraulic pressure corresponding to an input electric command to be generated in the clutch. When starting the vehicle, the first step of operating the pressure control valve corresponding to the auxiliary shift clutch to be engaged and the end of the filling time of the pressure control valve corresponding to the auxiliary shift clutch are confirmed. Activating a pressure control valve corresponding to the main shift clutch to be engaged and gradually increasing the hydraulic pressure of the sub shift clutch at an arbitrary inclination; When the step and the end of the filling time of the pressure control valve corresponding to the main transmission clutch are confirmed, a third step of gradually increasing the hydraulic pressure of the main transmission clutch at an arbitrary inclination, and after the completion of the filling time of the main transmission clutch , Detecting the state quantity corresponding to the clutch load of the main shift clutch,
And a fourth step of increasing the gradually increasing inclination of the main transmission clutch when the state quantity exceeds a predetermined value set in advance, and a transmission control method. 3. A speed stage comprising a plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft and a combination of the sub-shift clutch and the main shift clutch. Transmission to choose
A control method for a transmission, comprising: a plurality of pressure control valves that are individually connected to a plurality of clutches of this transmission and that generate hydraulic pressures corresponding to the input electric commands in the clutches. When the state quantity corresponding to the clutch load of one of the clutch and the auxiliary transmission clutch exceeds a predetermined prescribed value, the hydraulic pressure of the other clutch is temporarily reduced to a low pressure value. Method. 4. A plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft, wherein a speed is obtained by combining the sub-shift clutch and the main shift clutch. A transmission control method comprising: a transmission that selects a stage; and a plurality of pressure control valves that are individually connected to a plurality of clutches of the transmission and that cause a hydraulic pressure corresponding to an input electric command to be generated in the clutch. When starting the vehicle, the first step of operating the pressure control valve corresponding to the auxiliary shift clutch to be engaged and the end of the filling time of the pressure control valve corresponding to the auxiliary shift clutch are confirmed. Activating a pressure control valve corresponding to the main shift clutch to be engaged and gradually increasing the hydraulic pressure of the sub shift clutch at an arbitrary inclination; When the step and the end of the filling time of the pressure control valve corresponding to the main transmission clutch are confirmed, a third step of gradually increasing the hydraulic pressure of the main transmission clutch at an arbitrary inclination, and after the completion of the filling time of the main transmission clutch , Detecting the state quantity corresponding to the clutch load of the main shift clutch,
When the state quantity exceeds a preset predetermined value, a fourth step of reducing the auxiliary shift clutch to a predetermined low pressure value and maintaining this low pressure value; and when the engagement of the main shift clutch is confirmed, the auxiliary shift clutch is confirmed. And a fifth step for gradually increasing the hydraulic pressure of the above from an arbitrary hydraulic pressure value, and a control method for a transmission, comprising: 5. A plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft, wherein a speed is obtained by combining the sub-shift clutch and the main shift clutch. A transmission control method comprising: a transmission that selects a stage; and a plurality of pressure control valves that are individually connected to a plurality of clutches of the transmission and that cause a hydraulic pressure corresponding to an input electric command to be generated in the clutch. When starting the vehicle, the first step of operating the pressure control valve corresponding to the main speed change clutch to be engaged and the end of the filling time of the pressure control valve corresponding to the main speed change clutch are confirmed, Activating a pressure control valve corresponding to the auxiliary transmission clutch to be engaged and gradually increasing the hydraulic pressure of the main transmission clutch at an arbitrary inclination When the step and the end of the filling time of the pressure control valve corresponding to the sub speed change clutch are confirmed, a third step of gradually increasing the hydraulic pressure of the sub speed change clutch at an arbitrary inclination, and after the hydraulic pressure of the main speed change clutch is gradually increased, A fourth step of detecting a state quantity corresponding to the clutch load of the speed change clutch and, when the state quantity exceeds a preset predetermined value, reduces the auxiliary speed change clutch to a predetermined low pressure value and holds this low pressure value. And a fifth step of gradually increasing the hydraulic pressure of the sub speed change clutch from an arbitrary hydraulic pressure value when it is confirmed that the main speed change clutch is engaged, and a transmission control method comprising: 6. The method for controlling a transmission according to claim 1, wherein the state quantity is a clutch heat generation quantity or a clutch plate temperature. 7. A speed stage comprising a plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft and a combination of the sub-shift clutch and the main shift clutch. Transmission to choose
A transmission control method comprising: a plurality of pressure control valves that are individually connected to a plurality of clutches of this transmission and that generate hydraulic pressure corresponding to an input electric command in the clutch. When the filling of both the auxiliary shift clutch and the auxiliary shift clutch is completed, the difference between the relative rotational speed of the auxiliary shift clutch and the relative rotational speed of the main shift clutch is maintained at a predetermined value. A method for controlling a transmission, characterized in that the hydraulic pressure is controlled. 8. A plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft, wherein a speed is obtained by combining the sub-shift clutch and the main shift clutch. A transmission control method comprising: a transmission that selects a stage; and a plurality of pressure control valves that are individually connected to a plurality of clutches of the transmission and that cause a hydraulic pressure corresponding to an input electric command to be generated in the clutch. When starting the vehicle, the first step of operating the pressure control valve corresponding to the auxiliary shift clutch to be engaged and the end of the filling time of the pressure control valve corresponding to the auxiliary shift clutch are confirmed. A first control for actuating a pressure control valve corresponding to the main transmission clutch to be engaged and for maintaining the hydraulic pressure of the auxiliary transmission clutch at a predetermined low pressure value. When the step and the completion of the filling time of the pressure control valve corresponding to the main speed change clutch are confirmed, a third step of gradually increasing the hydraulic pressure of the main speed change clutch at an arbitrary inclination, and until the engagement of the main speed change clutch is completed. A fourth step of controlling the hydraulic pressure of either the auxiliary shift clutch or the main shift clutch so that the difference between the relative speed of the auxiliary shift clutch and the relative speed of the main shift clutch maintains a predetermined value, When the engagement of the clutch is finished, a fifth step of gradually increasing the hydraulic pressure of the auxiliary transmission clutch, and when the engagement of the auxiliary transmission is finished, a sixth step of raising the hydraulic pressure of the auxiliary transmission clutch to a specified value at a steep slope, A method for controlling a transmission, characterized in that 9. In the fourth step, the relative rotational speed ω1 of the auxiliary transmission clutch is compared with a value ω2 + α obtained by adding a predetermined value α to the relative rotational speed ω2 of the main transmission clutch, and if ω1 <ω2 + α, Decrease the oil pressure of the speed change clutch at an arbitrary gradient. If ω1 = ω2 + α, keep the oil pressure of the sub speed change clutch at the current value. If ω1> ω2 + α, increase the oil pressure of the sub speed change clutch at an arbitrary slope. 9. The method according to claim 8, wherein
A method for controlling the described transmission. 10. When lowering the oil pressure of the auxiliary shift clutch at an arbitrary gradient, it is prevented from falling below a predetermined minimum pressure, and when increasing the oil pressure of the auxiliary shift clutch at an arbitrary gradient, a predetermined maximum pressure. A control method for a transmission, characterized in that it is set so as not to exceed the limit. 11. A transmission comprising a plurality of sub-shift clutches at a first stage and a plurality of main shift clutches at a second stage from a transmission input shaft, wherein a speed is obtained by combining the sub-shift clutch and the main shift clutch. A transmission control method comprising: a transmission that selects a stage; and a plurality of pressure control valves that are individually connected to a plurality of clutches of the transmission and that cause a hydraulic pressure corresponding to an input electric command to be generated in the clutch. When starting the vehicle, the first step of operating the pressure control valve corresponding to the main speed change clutch to be engaged and the end of the filling time of the pressure control valve corresponding to the main speed change clutch are confirmed, Second step of actuating a pressure control valve corresponding to the auxiliary shift clutch to be engaged and gradually increasing the hydraulic pressure of the main shift clutch When the completion of the filling time of the pressure control valve corresponding to the sub speed change clutch is confirmed, the relative speed of the sub speed change clutch and the relative speed of the main speed change clutch are determined until the engagement of the main speed change clutch is completed. The fourth step of controlling the hydraulic pressure of either the sub speed change clutch or the main speed change clutch so that the difference between the main speed change clutch and the main speed change clutch is maintained. A fifth step of gradually increasing, and a sixth step of raising the hydraulic pressure of the auxiliary transmission clutch to a specified value at a steep gradient when the engagement of the auxiliary transmission is completed, Control method. 12. In the fourth step, the relative rotational speed ω1 of the auxiliary transmission clutch is compared with a value ω2 + α obtained by adding a predetermined value α to the relative rotational speed ω2 of the main transmission clutch. If ω1 <ω2 + α, Decrease the oil pressure of the speed change clutch at an arbitrary gradient. If ω1 = ω2 + α, keep the oil pressure of the sub speed change clutch at the current value. If ω1> ω2 + α, increase the oil pressure of the sub speed change clutch at an arbitrary slope. The method according to claim 1, characterized in that
2. The method for controlling the transmission according to 1. 13. When lowering the oil pressure of the sub-shift clutch at an arbitrary gradient, it is prevented from falling below a predetermined minimum pressure, and when increasing the oil pressure of the sub-shift clutch at an arbitrary gradient, a predetermined maximum pressure. A control method for a transmission, characterized in that it is set so as not to exceed the limit.