JPH0492158A - Speed change controller of continuously variable transmission - Google Patents

Abstract

PURPOSE:To quicken rise of torque of an output shaft by compensating an actuation amount to decide to the small side of a speed change ratio the more, the longer a detection time is in the case when the actuation amount of an electric actuator is on the large side of the speed change ratio rather than a target actuation amount at the time of down-shift. CONSTITUTION:Presupposed is a speed change control device of a stepless speed changer which has a target speed change ratio decision means to decide a target speed ratio in accordance with a driving condition and an actuation amount decision means of an electric actuator, which has an open loop actuation amount decision means and a closed loop actuation amount decision means to decide a closed loop actuation amount in accordance with deflection between the target speed change ratio and an actual speed change ratio. Then, a time after a throttle opening comes to be more than a specific amount is detected by a time detection means, and in the case when an actual actuation amount of the electric actuator is on the large side of the speed change ratio rather than the target actuation amount at the time of down-shift, the longer the time is, the more the actuation amount of the electric actuator decided by the actuation amount decision means is corrected to the small side of the speed change ratio by an actuation amount correction means.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a speed change control device for a continuously variable transmission.

(B) Prior art As a conventional speed change control device for a continuously variable transmission, for example, Japanese Patent Application Laid-Open No. 1983-1999. There is one shown in the publication No.-1.05351.

The gear change control device for the continuously variable transmission shown in this figure determines a target gear ratio from the vehicle speed and engine load, and operates the electric actuator of the continuously variable transmission to achieve this target gear ratio. It is configured. The amount of operation of the electric actuator is determined as follows. That is, the amount of operation of the electric actuator is the sum of the amount of open loop operation and the amount of closed loop operation.

The open loop operating amount is determined by a function using the target speed ratio as a variable. Further, the closed loop operation amount is determined as a function using the deviation between the target speed ratio and the actual speed ratio as a variable.

(c) Problems to be Solved by the Invention However, the conventional speed change control device for a continuously variable transmission as described above has the following problems. That is, during a downshift (shift to a larger gear ratio), the rise of the torque of the output shaft is delayed, resulting in poor responsiveness. This is due to the following reasons. That is, when the accelerator pedal is depressed for downshifting, the open-loop operation amount and the closed-loop operation amount become on the larger gear ratio side, and the actual operation amount of the electric actuator changes to the larger gear ratio side. At the same time, the input rotational speed starts to increase, and the actual manual rotational speed (gear ratio) approaches the target input rotational speed (gear ratio). Therefore, the amount of closed loop operation becomes smaller, and the amount of operation of the electric actuator changes toward the smaller gear ratio side. The actual manual rotation speed reaches the target input rotation speed and the output shaft torque increases. In order to speed up the rise of this torque, it is necessary to quickly switch the operating amount of the electric actuator from the downshift direction to the upshift direction, but with conventional control devices, the closed loop operating amount does not easily decrease, so the above operation is not possible. The reversal of quantity was delayed. For this reason, as mentioned above, the rise in torque was delayed.

The present invention aims to solve these problems.

(d) Means for Solving the Problems The present invention solves the above problems by correcting the operation amount of the electric actuator to the smaller gear ratio side in accordance with the passage of time from the increase in throttle opening. That is, the present invention provides a speed change control device for a continuously variable transmission in which the speed ratio is controlled according to the amount of operation of an electric actuator, and includes target speed ratio determining means (step) for determining the target speed ratio according to operating conditions. 504) and operation amount determination means for determining the operation amount of the electric actuator, the operation amount determination means being open-loop operation amount determination means for determining the open-loop operation amount of the electric actuator according to the target gear ratio. (Step 506), and closed-loop operation amount determining means for determining the closed-loop operation amount of the electric actuator according to the deviation between the target gear ratio and the actual gear ratio (Step 508)
This is based on the premise that the device has a time detection means (steps 503, 514) that detects the time after the throttle opening reaches a predetermined value, and a time detection means (steps 503 and 514) that detects the time elapsed since the throttle opening reaches a predetermined value, and a time detection means (steps 503, 514) that detects the amount of operation of the electric actuator when the downshift is performed. When the operation amount is on the larger side of the gear ratio than the operation amount, the longer the time detected by the time detection means, the more the operation amount of the electric actuator is determined by the operation amount determining means. Correction means (step 509.511513
).

Note that the operation amount of the electric actuator may be corrected to the smaller gear ratio side in accordance with a deviation when the actual value is on the larger gear ratio side than the target value.

Furthermore, controlling the gear ratio and controlling the input rotational speed are substantially the same thing.

(e) Operation The operation amount of the electric actuator is corrected to the smaller speed ratio side as the time elapses after the throttle opening exceeds a predetermined value. By doing this, the operation amount is quickly reversed from the downshift direction to the upshift direction, and the torque of the output shaft quickly rises and falls.

(F) Embodiment FIG. 2 shows a power transmission mechanism of a continuously variable transmission. This continuously variable transmission is a fluid coupling] 2, forward/reverse switching mechanism 15
, (2) a belt type continuously variable transmission mechanism 29, a differential device 56, etc., and can transmit the rotation of the output shaft 10a of the engine 10 to the output shafts 66 and 68 at a predetermined gear ratio and rotation direction. This continuously variable transmission has a fluid force/tubling 12 (lockup oil chamber 12a, pump impeller 12b).
, turbine runner 12c, lock-up clutch 1.2
d etc.), rotating shaft 13, drive shaft 14, forward/reverse switching mechanism 15, drive pulley 16 (fixed conical member 18
, drive pulley cylinder chamber 20 (chamber 20a, chamber 20b),
(consisting of movable conical member 22, groove 22a, etc.), planetary gear mechanism 17 (consisting of sun gear 19, binion gear 21, binion gear 23, binion carrier 25, internal gear 27, etc.), belt 24, driven pulley 26 (fixed conical member) 30, driven pulley cylinder chamber 32, movable conical member 34, etc.), driven shaft 28, forward clutch 4o, drive gear 46, idler gear 48, reverse brake 50, idler shaft 52, pinion gear 54, final gear 44, pinion gear 58, Binion gear 60,
Although it is composed of a side gear 62, a side gear 64, an output shaft 66, an output shaft 68, etc., a detailed explanation thereof will be omitted. The structure of the parts whose explanation is omitted is described in Japanese Patent Application Laid-Open No. 61-105353, which is the origin of the present applicant.
It is stated in the No.

FIG. 3 shows the hydraulic control system for the continuously variable transmission. This hydraulic control device includes an oil pump 101 and a line pressure regulating valve 102.
, manual valve 104, speed change control valve 106, adjustment pressure switching valve 108, temperature control valve 110, speed change operation mechanism 112
．． Throttle valve 114, constant pressure regulating valve 116, solenoid valve]
18, a coupling pressure regulating valve 120, a lock-up control valve 122, etc., which are connected to each other as shown in the figure, and a forward clutch 40, a reverse brake 50, a fluid coupling 12, a lock-up oil The chamber 12a, the driving pulley cylinder chamber 20, and the driven pulley cylinder chamber 32 are also connected as shown. A detailed explanation of these valves and the like will be omitted. The parts whose explanation is omitted are described in the above-mentioned Japanese Patent Laid-Open No. 105353/1983. In addition, each reference numeral in FIG. 3 indicates the following members. Binion gear 110a, tank 130,
Strainer 131, oil passage 132° leaf valve 133, valve hole 134. Boats 134a-e, spool 136, lands 136a-b, oil passage 138, one-way orifice 139
, oil passage 140, oil passage 142, one-way orifice 143° valve hole 146, boat 146a=g, spool 148, lands 148a-e, sleeve 150, spring 152
, spring 154, gear ratio transmission member 158, oil passage 16
4, oil passage 165, orifice 166, orifice 171
0, valve hole 172, boat 172a-e, spool 174
, land 174a=c, spring 175, oil passage 176
, orifice 177, lever], 78, oil passage 179,
Bin 181, rod 182, lands 182a-b, rack 182c, bin 183, bin 185, valve hole 186, boat 186a-d, oil passage 188, oil passage 189, oil passage 19
0, valve hole 192, boat 192a-g, spool 194
, lands 194a-e, negative pressure diaphragm 198, orifice 199, orifice 202. Orifice 203
, valve hole 204, port 204 a = e, spool 206, land 206 a - b, sub 1 nong 208
, oil passage 209, filter 211, filter 216
, port 222, solenoid 224, plunger 224
a. Suburunonku.

225, valve hole 230, port 230 a = e spool 232, land 232a-b, sub 234,
Oil passage 235, orifice 236, valve hole 240, port 2
40a-h, spool 242, land 242 a-e
, oil passage 243, oil passage 245, orifice 246, orifice 247, orifice 248, orifice 249, choke type throttle valve 250, relief valve 251, choke type throttle valve 252. Pressure holding valve 253, oil passage 254, cooler 256, cooler pressure holding valve 258, orifice 259, switching detection switch 278°. IO and solenoid 2
24 is shown. The electronic control device 300 includes a human interface 311, a reference pulse generator 312, a CPU (central processing unit) 313. R
It has an OM (read only memory) 314, a RAM (random access memory J) 31.5, and an output interface 316, which are communicated by an address bus 319 and a pig bus 320. This shift control device 300 includes an engine rotation speed sensor 301, a vehicle speed sensor 302, a throttle opening sensor 303, a shift position switch 304, a turbine rotation speed sensor 305, an engine coolant temperature sensor 306, a brake sensor 307, and a switching detection switch. 298 directly or waveform shapers 308, 309 and 322,
and is input through the AD converter 310, while the amplifier 3
17 and the step motor 110 through the line 317a=d.
A signal is output to the solenoid 224, and a signal is also output to the solenoid 224, but a detailed explanation of these will be omitted.

Note that the structure of the portions whose explanations are omitted are described in Japanese Patent Application Laid-Open No. 105353/1983 mentioned in No. 11.

The amount of operation of the step motor 110, which is an electric actuator, is determined according to the control flow shown in FIG.

First, the human rotation speed Nt, the vehicle speed vSP, and the throttle opening TVO are determined by the turbine rotation speed sensor 30, respectively.
5. Read from vehicle speed sensor 302 and throttle opening sensor 303 (step 501). Next, the throttle opening TVO is a predetermined large value T. The above is the same to judge whether it is futai or not! >02), TVO or T, in this case it is necessary to judge whether the flag is set or not.
02a), if it is not set, set the timer t to 0 (503), and then set the flag (503).
a). Meanwhile, TVO is T. If it is smaller than , the flag is canceled (502b). Next, the target input rotational speed T-Nt, which is set as a function of the vehicle speed VSP and the throttle opening TVO, is calculated based on the read VSP and TVO (step 504).

That is, T-Nt=f (VSP, TVO) Note that the function f is set to have a characteristic as shown in FIG.

Next, the open loop operation amounts θ and F are calculated using the following equations (step 506).

θrr=g (TN t/VSP) Note that the function g is set to have a characteristic as shown in FIG.

Next, the actual manual rotation speed Nt and the target input rotation speed T
-Nt is determined (step 507), and the closed loop operation amount θFB is calculated using the following formula (step 508).

θ1−B=K p X e+ΣK1Xe Note that Kp and Ki are constants.

Next, find the correction value H by the timer t (509
). That is, H=h (t) Note that the function is set to have characteristics as shown in FIG.

Next, a correction value S based on the vehicle speed VSP is determined (510
). That is, S=j (VSP) Note that the numerical aperture J is set to a characteristic as shown in FIG.

Next, determine whether θ is negative or not (511)
, if positive, θF and θF8 are added and this is set as the step motor rotation angle θm (step 512). That is, θm=θFF+θF8 On the other hand, if 01B is negative, 0m is calculated using the following formula (513).

θm=θFF10, B+HX S Then, the step motor 110 is rotated to 0 m (514), and the value of t plus 1 is newly set as t (5th step 5).

In the end, through the above control, the target gear ratio is first determined according to the operating conditions (step 504), and the open loop operating amount is determined according to the target gear ratio (step 506).
, the closed loop operating amount is determined according to the deviation between the target gear ratio and the actual gear ratio (step 508), and in the normal case, the step motor rotation angle θm is determined based on the sum of both operating quantities. (Steps 511→512).

However, if the gear ratio is on the larger side than the actual step motor rotation angle or the target step motor rotation angle during downshifting, the longer the time since the throttle opening has become larger than the predetermined value, Also, the lower the vehicle speed, the larger the step motor rotation angle θm is corrected (steps 509→510→511→513). If the step motor rotation angle θm increases, the gear ratio will be corrected to the smaller side. Therefore, the step motor 110 is quickly switched from the operating state in the town shift direction to the up shift direction, and the actual input rotation speed quickly reaches the target manual rotation speed.

By doing this, the torque of the output shaft can be increased quickly.

Incidentally, in the above embodiment, the correction is performed according to the timer value t, but in step 509, t is changed to the deviation e,
The correction value may be increased accordingly. Further, step 510) of adjusting the degree of correction depending on the vehicle speed is not necessarily required.

(G) As described in detail, according to the present invention, the operating amount of the electric actuator is corrected to the small gear ratio side in accordance with the passage of time or deviation, so that It is possible to accelerate the reversal in the upshift direction and to accelerate the rise of torque on the output shaft.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the relationship between the constituent elements of the present invention, Fig. 2 is a skeleton diagram of the continuously variable transmission, Fig. 3 is a diagram showing the hydraulic circuit, and Fig. 4 is a diagram showing the relationship between the components of the present invention.
Figure 5 shows the electronic control unit, Figure 5 shows the control flow, Figure 6 shows the characteristics of the target input rotation speed, Figure 7 shows the characteristics of the open loop operation amount, Figures 1 and 8 9 is a diagram showing the characteristics of the timer correction value, and FIG. 9 is a diagram showing the characteristics of the vehicle speed correction value. Figure 6 Figure 7 T-Nt/VSP

Claims (1)

[Scope of Claims] 1. A gear change control device for a continuously variable transmission in which the gear ratio is controlled according to the amount of operation of an electric actuator, comprising target gear ratio determining means for determining the target gear ratio in accordance with operating conditions. and operation amount determination means for determining the operation amount of the electric actuator, and the operation amount determination means includes open-loop operation amount determination means for determining the open-loop operation amount of the electric actuator according to the target gear ratio; In a gear change control device for a continuously variable transmission, the gear change control device includes a closed loop operation amount determining means for determining a closed loop operation amount of an electric actuator according to a deviation between a target gear ratio and an actual gear ratio, when the throttle opening is equal to or greater than a predetermined value. and a time detection means for detecting the time elapsed since 1. A speed change control device for a continuously variable transmission, comprising operation amount correction means for correcting the operation amount of the electric actuator determined by the operation amount determination means to a smaller gear ratio. 2. A gear change control device for a continuously variable transmission in which the gear ratio is controlled according to the amount of operation of the electric actuator, the target gear ratio determining means determining the target gear ratio according to the operating conditions, and the operation of the electric actuator. operation amount determining means for determining the open-loop operation amount of the electric actuator according to the target gear ratio; In a speed change control device for a continuously variable transmission, which has a closed-loop operation amount determination means that determines the closed-loop operation amount of the electric actuator according to the deviation from the ratio, the actual operation amount of the electric actuator and the target operation amount are determined. a movement amount deviation detection means for detecting the deviation of 1. A shift control device for a continuously variable transmission, comprising operation amount correction means for correcting the operation amount of the electric actuator determined by the operation amount determination means to a smaller gear ratio as the operation amount determination means increases. 3. The shift control device for a continuously variable transmission according to claim 1 or 2, wherein the lower the vehicle speed, the more the correction amount by the operation amount correction means increases.