JPS63130951A - Automatic transmission gear for vehicle - Google Patents

Abstract

PURPOSE:To smoothly perform speed change of the transmission gear in the caption by transmitting the transmitting torque of one speed change step to a speed change step having a multiple disk clutch at the time of speed change, and directly connecting the gear of the other speed change step to a shaft thereafter. CONSTITUTION:A shift clutch 12 comprising a multiple disk clutch is provided on an input shaft 5, on which is also mounted a 5-speed step gear 15a, which is put in/released from action by a shift actuator 13, in such a way as to allow idle running. At the time of speed change, the shift clutch 12 is controlled, and after the transmitting torque of one speed change step is transmitted to the shift clutch 12, the idle-running gear 15a of the other speed change step and the input shaft 5 are substantially synchronized as well as directly connected to each other. Therefore, torque is successively transmitted to an output shaft 14 during speed change, so that smooth speed change can be achieved without any feeling of lost power.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic transmission for a vehicle, and particularly to an automatic transmission for a vehicle suitable for automatically shifting gear transmissions.

[Conventional technology]

Hydraulic type automatic transmissions that use torque converters are the mainstream for automobiles, but power transmission by torque converters involves loss, and they are inferior to gear transmissions in terms of fuel consumption. Automation of gear transmissions has been delayed in practical application because the control is rotary compared to hydraulic type.
Several devices have been published utilizing modern electronics.

One such device is the device described in Japanese Patent Application No. 59-166438, which, when a gear shift condition is reached, shifts the transmission to a desired gear by placing it in neutral, and then increasing the operating force of a multi-disc clutch to input the gear. The shaft and output shaft are synchronized to change speed. This is the same shifting method as a manual transmission.

[Problems to be Solved by the Invention] The above-mentioned transmission device puts the transmission in neutral when changing gears, and during that time, driving torque is not transmitted to the vehicle, giving the driver a feeling of weakness and impairing comfort. Naturally, a manual transmission also causes a feeling of weakness, but this occurs when the driver consciously shifts gears, and the driver anticipates this, so it is not a problem.

In the case of an automatic transmission, the driver cannot predict when the gear will change, and therefore feels uncomfortable due to the sudden feeling of weakness.

Furthermore, since the torque generated by the engine connected to the input shaft is not controlled during gear shifting, the transmission torque changes in steps due to changes in the gear ratio before and after gear shifting.

An object of the present invention is to eliminate the feeling of weakness during gear shifting and to perform smooth gear shifting.

c. Means for Solving Problem] The above problem is caused by an input shaft and an output shaft that idly support one gear of a plurality of gear pairs having different gear ratios and fixedly support the other gear. The gears spin idly,
In an automatic transmission, a torque transmission means is provided between the gear and a shaft that supports the gear in idle rotation, and the gear ratio of the input/output shaft is automatically changed by selectively switching the torque transmission means. The torque transmission means is a multi-disc clutch, and when shifting from one gear to the other gear, the multi-disc clutch is controlled to transfer the transmitted torque of the one gear to the gear shift having the multi-disc clutch. This problem can be solved by taking measures to substantially synchronize and directly connect the idling gear of the other gear and the shaft supporting the gear after transmission to the other gear.

[Effect]

When shifting from one gear pair of gears (hereinafter referred to as A) to the other gear pair of gears (hereinafter referred to as B), the gear pair of a gear gear with a smaller gear ratio than A and B (hereinafter referred to as C) If you increase the pressing force of the provided clutch against the clutch plate and adjust it so that the rotational speed is slightly higher than the rotational speed of the output shaft driven by A, the output shaft will be driven by A more than the input shaft. The torque being transmitted is C
Since the torque is transmitted to the output shaft by 4A, the torque transmission means of A can be released.

Next, if the shift from A to B is a speed increase shift, as the pressing force on the clutch plate increases, the slip between the clutch plate and the idling gear decreases, and the gear shifts to a high speed.
Even if the torque of the output shaft is constant, the torque of the input shaft increases, so the rotational speed of the engine, that is, the rotational speed of the input shaft, decreases in order to increase the torque generated by the engine connected to the input shaft. When the rotational speed of this input shaft becomes equal to the rotational speed corresponding to B, which corresponds to the rotational speed of the output shaft,
That is, when synchronized with B, a speed-up shift can be performed by fixing the torque transmission means between the idling gear B and the shaft.

If the shift from A to B is a deceleration shift, as the pressing force on the clutch plate decreases, the slip between the clutch plate and the idling gear increases and the gear shifts to a lower gear, causing the output shaft to decrease. Even if the torque is constant, the torque of the input shaft decreases, so the torque generated by the engine connected to the input shaft decreases, so the rotational speed of the engine, that is, the rotational speed of the input shaft increases.

The rotation speed of this input shaft is B according to the rotation speed of the output shaft.
When equal to the rotational speed corresponding to B and synchronized with B, a downward shift can be performed by fixing the torque transmission means of B.

Further, the B torque transmission means is a clutch.

When increasing the speed, increase the pressing force of the clutch against the clutch plate and adjust the rotation speed to be slightly higher than the rotation speed of the output shaft driven by A. The torque that was being transmitted from the shaft to the output shaft is now transmitted to the output shaft by B, and A
Since A is released from torque transmission, the torque transmission means of A can be released. Next, the pressing force of the B clutch against the clutch plate is increased until there is no slippage, and the shift to B is completed.

When the torque transmission means of A is a clutch and the gear is decelerated, as the pressing force of the clutch against the clutch plate is reduced, the slip between the clutch plate and the idling gear increases and the gear shifts to a lower gear. As a result, even though the output shaft torque remains constant, the input shaft torque decreases, so the rotational speed of the engine connected to the input shaft, that is, the rotational speed of the input shaft increases. When the rotational speed of this input shaft becomes equal to the rotational speed corresponding to B, which corresponds to the rotational speed of the output shaft, it is fixed to the torque transmission means of B, and the clutch of A is released.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 15.

FIG. 1 is a system diagram of one device.

The engine 1 has a throttle valve 2 in the intake pipe, and a control circuit 8
The throttle valve is opened and closed by a throttle valve actuator 6 which is activated by a signal from the throttle valve. The output of engine 1 is the starting clutch 3
is transmitted to the input shaft 5 of the transmission via the first gear pair 2.
6a, 27a to 4th speed gear pair 26d to 27d, and 5th speed gear pair 15a.

The signal is transmitted to the output shaft 14 via the output shaft 15b, and is transmitted to the axle from the final reduction gear 20 provided on the output shaft 14. The first speed gear 27a to the fourth speed gear 27d are mounted on the output shaft 14 in a state where they can idle. Note that the reverse gear is not shown because it is not directly related to the present invention.
A 5th gear gear shaft 15 is attached to the top so that it can idle.
a is connected to or released from the input shaft 5 by the speed change actuator 13 operated by a signal from the control circuit 8. When the clutch is connected, the first speed gear 26a.

The torque that has been transmitted to the output shaft by any of the gear pairs 27a to 4th gear 26d and 27d is transferred to the 5th gear gear pair 15a.
, 15b.

The starting clutch 3 is connected and released by a starting clutch actuator 4 operated by a signal from a control circuit 8. 1 attached to the output shaft 14 so that it can idle
The speed gear 27a and the second speed gear 27b are fixed to and released from the output shaft 14 by a sleeve 28 provided between the two, and the sleeve 28 is driven by the switching actuator 17 operated by a signal from the control circuit 8. Similarly, the third speed gear 27c and the fourth speed gear 27d, which are attached to the output shaft 14 so that they can idle, are fixed to and released from the output shaft 14 by a sleeve 29 provided between them, and the sleeve 28 is connected to the control circuit 8. It is driven by a switching actuator 16 which is activated by a signal from

The switching actuators 4, 13, 16, 17 are driven by hydraulic pressure and the hydraulic tank 9. A hydraulic pump 10 is connected to a hydraulic pressure generating device consisting of a hydraulic regulator 11.
The control circuit 8 that controls this device includes the output of an accelerator signal generator 24 that detects the position of the accelerator pedal, and the output of an accelerator signal generator 24 that detects the position of the accelerator pedal.
), Parking (P).

A switch 18 for selecting a driving mode such as forward (D). Signal Tp of the gear position of the transmission.

Engine speed Na and vehicle speed N are input. The output signal is the throttle valve 9 transmission clutch and the speed change clutch.

There is a drive signal for the switching actuator.

FIG. 2 is an explanatory diagram of the operation of the device according to the present invention at the time of starting.

When the driver selects rDJ with the select switch 18 in FIG. 1 and depresses the accelerator pedal 23, the vehicle starts moving. The switching actuator 17 moves the sleeve 28 to the 1st gear gear 27a to connect the input shaft and the output shaft (1st gear) 0
The starting clutch actuator 4 connects the starting clutch in a half-clutch state. At this time, the connection speed Vc of the starting clutch actuator 4 is calculated by Vc''Kzθa · (D where 1Kg: constant, θ&: accelerator opening degree.

Furthermore, the strength of the connection when the clutch is engaged in a partially engaged state is determined by the engine rotation speed Ne. By connecting with a half-clutch, when Ne becomes smaller than the set rotation speed, the half-clutch is weakened,
If it is higher than that, the half-clutch is strengthened and the connection speed Vc
When the 6-start clutch is fully connected, the start is completed and the vehicle enters 1st gear operation.

FIG. 3 shows the operation when shifting from 3rd speed to 4th speed.

FIG. 3(a) shows third speed operation. The driving torque To during gear shifting when the third speed gear 27c is connected to the output shaft 14 through the sleeve 29 is expressed by the following equation.

To = KIX θaXTps
-(2) where Kl: Constant θa: Mini accelerator Tps: 3rd speed gear ratio The transmission torque Tc of the one-speed clutch 12 is.

Tc == KaX Pc ・
・(3) Here, Ka: Constant Pc: Represented by the operating pressure of the speed change clutch actuator.

Therefore, in order to release the torque applied to the output shaft by the third speed gear pair 26c, 27c, it is necessary to set Pa so that Tc=To and transfer the transmitted torque to the fifth speed gear pair 15a, 15b. For torque transmission, the rotational speed of the output shaft in the 5th gear may be set to be slightly higher than the rotational speed of the output shaft in the 3rd gear.

In this way, it is possible to move to the fifth gear without substantially changing the transmitted torque. FIG. 3(b) shows this state. FIG. 3(c) shows the state in which the sleeve 29 has been removed from the third gear gear 27c. Since the third gear is no longer transmitting torque, the sleeve 29 can be easily removed from the 0th and 5th gears. Transmission of torque from the gear pair 15a, 15b to the fourth gear gear pair 26d, 27d will be explained.

Currently, the torque is transmitted to the output shaft by the 5th gear gear pair 15a and 15b, but the transmission clutch 12 is used to connect the input shaft to the 5th gear gear 1.
5a is in a state of sliding. As the operating pressure Pc of the speed change clutch actuator 13 is increased, the shift becomes smaller, and the gear ratio changes from 3rd gear to 4th gear to 5th gear.When the gear ratio reaches 4th gear, the gear ratio becomes smaller. Figure 3 (d
), the sleeve 29 is switched by the switching actuator 16, and the fourth speed gear 27d is coupled to the output shaft.

Next, the operating pressure pc of the speed change clutch actuator 13 is reduced, the transmission torque of the speed change clutch 12 is released, and the shift from the third speed to the fourth speed is completed.

FIG. 4 is a detailed structural diagram of the control circuit 8 of FIG. 1. The analog input signal is the output θ of the accelerator signal generator 24.
a. Operation pressure detector 2 of the speed change clutch actuator 13
2 signal PC9 start There is a stroke La of the start clutch actuator, etc.

These signals are input to the multiplexer 130, each signal is selected in a time-division manner, and the AD converter 131
where it is converted into a digital signal. Information input as an on-off signal is "R" of the select switch 18.

There are rPJ, rDJ, the idle position of the accelerator pedal 23, and the gear position of the transmission iiTFz~Tpa, which are treated as 1-bit digital signals. Furthermore, as a pulse train signal, vehicle speed N, engine rotation speed N
e is also input. The ROM 132 is a storage element that stores control programs and fixed data, and the CPU 133 is a processing central unit that performs digital arithmetic processing. RAM 134 is a readable and writable storage element. The circuit 135 sends signals from the AD converter 131 and each sensor to the CPU 133, and also sends signals from the CPU 133 to the throttle actuator 6, starting clutch actuator 4. Speed change clutch actuator 13. and sleeve switching actuator 16
, 17.

Flowcharts of the control circuit programs are shown in FIGS. 5 to 8, and each program is executed in a time period according to a time schedule.

FIG. 5 is a flowchart of "speed change pre-processing". "Speed change processing"
is executed with a period of 20 ms. In FIG. 5, the "P" position of the select SW is determined.

In the case of 2nd place 1fYas, the process ends with all flags OFF, the transmission clutch released, and gear neutral. P position NO.
In other words, in the case of rRJ or rDJ, θa.

Take in Tp w Pc t Np Nll. 2
At step 04, it is determined that N≦7.5 Km/h, and if Yes, the start flag is turned on. If NO, bus 205.

The shift flag is determined at 206, and if it is OFF, the shift flag is determined at 207.
to determine whether to shift. In the case of Ygg, turn on the shift flag and turn off the shift preparation flag. If NO, bus 208.

At 209, the selection switch rRJ is determined and R(Ya
In the case of s), determine NN-0K/h at 210a
If N = OK m/h (Yes, the car has stopped), turn on R (reverse). If N>OKm/h, the process ends.If the select switch is set to D (No) in 209,
Determine the start flag at 211, and if it is ON, shift to 1st gear.0If the start flag is OFF, determine the change in N at 214, and if the change is positive, search the shift up map, and if it is negative, shift. Search the down map. If the shift flag is ON at 206, Pea”KzXθaXTpn ・(2
') Here, Pco: The target shift actuator operating pressure is calculated, and PcaPco is determined in step 218.

If No, increase Pc and complete @Y6B, Pc=
Determine Po, and if No, lower Pc and end. Y
In the case of es, Pc is held. At step 223, the gear position is determined, and if it is not in neutral (No), it is set to neutral and the process ends.If it is in neutral, the shift preparation flag is turned ON and the gear change flag is turned OFF and the process ends.

FIG. 6 is a flowchart of the "speed change clutch control" program. This program is also executed at a cycle of 20 m's. In FIG. 6, when the shift preparation flag is ON, the issue flag is OFF, and the idle 5W is OFF, 203 (7) N eo = N
-(4) Neo: Calculate the target engine speed. Take in Ne at 231, Ne> at 232
Determine Neo+50 @ If Yes, raise Pc to lower No and end, if NO, Ns at 233>
Determine Neo-50, if No, lower Pc to raise Ne, complete eIf Yes, turn on gear at 234.
Make a judgment. If the gear is not engaged (NO), the gear is engaged and the process is completed; if the gear is engaged (Yes), the gear change clutch is released and the shift preparation flag is turned OFF to complete the process.

Figure 7 shows a special case of downshifting when stopping the car.
12 is a flowchart of ``r shift down special control'' when the vehicle is stopped in neutral from the gear position in the running state. This program is executed in 5 cycles of 40 m. The idle switch is ON, the gear is not neutral, and the start flag is OFF, and 243 No is taken in. 244 is determined to be idle (800 rpm + m), and if Yes, it is set to neutral and the process ends.

FIG. 8 is a flowchart of "starting clutch control". This program is executed in 80m5 cycles. 24
Determine the start flag in step 6, and if it is OFF, it is finished, and it is ON.
In this case, 247 is used to determine neutral. If it is neutral (Yes), the starting clutch is determined at 259, and if it is engaged, the clutch is disconnected and the process ends.If it is disconnected, the shift preparation flag is determined at 261, and if it is OFF, it is finished, and if it is ON, the process ends. , put the gear (1st gear) and finish, 247
If it is not neutral (No, 1st gear), set the shift preparation flag to 0FFL, determine the idle sw with 249,
When ON (in case of idling), the start clutch is disconnected and the operation ends. When the idle SW is OFF, V c = K x Xo!
-(1) is calculated and Vc is set. 253 and Ns7
．． 5Km/h, if 08515% is Yes, 25
The half-clutch state is determined in step 4, and if the half-clutch is strong (Nil is smaller than the set value), the half-clutch is weakened and the process ends (return the starting clutch with Vc).

If the half-clutch is weak (if NO is greater than the set value)
continues the connection with Vc and ends, if 253 is NO, 2
57 determines whether the clutch is engaged, and if it is not completely connected (N
O) ends, and if connected, turns off the start flag and ends.

Figure 9 shows a shift map, where the X axis is N and the y axis is θ.
It is a. A solid line indicates an upshift, and a broken line indicates a downshift. Hysteresis is provided between upshifts and downshifts to prevent hunting. In addition, during downshifting, when θa is a low opening degree, the downshifting vehicle speed is reduced to widen the coasting range.

FIG. 10 shows the experimental results of a device according to the present invention. 1st
Figure 0 shows changes in the longitudinal acceleration of the vehicle when starting and shifting gears.The present invention changes the G at starting faster than the conventional device, and there is no change when shifting gears.

FIG. 11 shows another embodiment of the invention. In this figure, speed change clutches 50a, 50b, and 50c.

It has 50d. When the speed change clutch 50a is connected by the switching actuator 17, the input shaft 5→1st speed change gear 2
Torque is transmitted from 6a to 27a to transmission clutch 50a to output shaft 14, and the gear is shifted to first speed. The shift from the first speed to the second speed is completed by releasing the speed change clutch 50a with the switching actuator 17 and connecting the speed change clutch 50b. In this way, by providing the gear change clutches in accordance with the number of gears, the gear change operation becomes very simple. However, since there is no variable speed clutch that is small and has a large transmission torque, there is a drawback that the transmission becomes large.

FIG. 12 shows the relationship between the accelerator opening degree θ and the drive torque Te of the output shaft 14. In this figure, when the transmission is in first speed, the gear ratio is large, so Te is large. Also 5
Since the gear ratio is small in the case of high speed, Te is also small.

FIG. 13 shows the operating pressure Pc of the speed change actuator 13 and the driving torque T of the output shaft 14. The transmission clutch 12 is a multi-plate clutch, and the transmitted torque is proportional to the force (operating pressure Pc) applied to the clutch plates.

Therefore, as pc increases, Ts also increases.

FIG. 14 is a block diagram showing a portion of FIG. 5 showing a method of preloading the speed change actuator.

It is determined in step 201 whether or not the state of the select SW is rPJ. If not “P”, i.e. rRJ or rDJ
In the case of θa e Tpn, Pco is calculated from Kl. At 218, the calculation result at 217 is compared with Pc, and if NO, the shift actuator 13 shown in FIG.
Turn the operating valve Vz30 ONL to increase Pa. 21
If 8 is Yes, the judgment is made again in 219. If NO, the operation valve v131 of the speed change actuator 13 is turned on and P
Decrease C. If Yes, V130. Set both Vz31 to 0FFL and determine whether the gear position is neutral at 223. If it is not neutral (NO), the switching actuators 16 and 17 are set to neutral.

If the determination in step 223 is Yes (if the vehicle is neutral), the shift preparation flag is turned ON and the shift flag is turned OFF.

FIG. 15 is a structural diagram of the speed change actuator 13.

The speed change actuator 13 includes an operating pressure detector 22 and an operating valve V130. There is a control valve v231. Valve Vx30 is connected to the pump boat, and when valve v130 is opened, pressure oil is supplied. Valve v231 is connected to a drain boat, and when valve Vz31 is opened, hydraulic oil is discharged.

〔Effect of the invention〕

According to the present invention, during gear shifting, torque is transmitted from the gear gear pair before gear shifting to the gear gear pair having a clutch, and further,
After adapting the gear ratio of the input shaft and output shaft to the gear ratio of the gear to be shifted, torque is transmitted from the gear pair having the clutch to the gear pair of the gear to be shifted, so that the torque during the gear shifting period is It is continuously transmitted to the output shaft, achieving smooth gear changes without any feeling of weakness.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing an embodiment of the present invention, Fig. 2 is an explanatory diagram showing the operation at the time of starting, Fig. 3 is an explanatory diagram showing the operation at the time of shifting, and Fig. 4 is a detailed structural diagram of the control circuit. , FIG. 5 is a flowchart of the "shift preprocessing" program, FIG. 6 is a flowchart of the "shift clutch control" program, and FIG. 7 is a flowchart of the "shifting clutch control" program.
Flowchart of the “shift down special control” program,
Fig. 8 is a flowchart of the "starting clutch control" program, Fig. 9 is a shift map diagram, Fig. 10 is an experimental result of the device according to the present invention, Fig. 11 is another embodiment of the invention, and Fig. 12 is an accelerator opening diagram. 13 is a diagram showing the relationship between the operating pressure Pc of the speed change actuator and the drive torque To of the output shaft. FIG. 14 is a block diagram showing the preloading method for the speed change actuator. The figure is a structural diagram of a speed change actuator. 1.゛°Engine, 3... Starting clutch, 5... Input shaft, 8... Control circuit, 12... Speed change clutch, 1
4...Output shaft.

Claims (1)

[Scope of Claims] 1. A idling gear consisting of an input shaft and an output shaft that idly supports one gear of a plurality of gear pairs and fixedly supports the other gear of a plurality of pairs of gears each having a different gear ratio; In an automatic transmission, a torque transmission means is provided between the gear and a shaft that supports the gear in idle rotation, and the gear ratio of the input/output shaft is automatically changed by selectively switching the torque transmission means. The torque transmission means is a multi-disc clutch, and when shifting from one gear to the other gear, the multi-disc clutch is controlled to transfer the transmitted torque of the one gear to the gear shift having the multi-disc clutch. An automatic transmission for a vehicle, characterized in that, after the transmission is transmitted to the other gear, the idling gear of the other gear and a shaft supporting the gear are substantially synchronized and directly connected. 2. The device according to claim 1, wherein the torque transmission means for each gear pair are all clutches.