JPS62270864A - Lockup mechanism controller for transmission - Google Patents

Abstract

PURPOSE:To make proper control over a lockup mechanism performable at all times, by setting a feedback controlled variable on the basis of a feedback gain conformed to a deviation in sliding velocity of a hydraulic power transmission and another feedback gain conformed to engine load. CONSTITUTION:A difference between engine speeds at both input and output sides of a hydraulic power transmission, to be detected by each of engine speed detecting devices A and B at both input output sides is calculated at an operational device C. And, a deviation between this engine speed difference and a desired engine speed difference out of a setting device D is calculated at a deviation operational device E, and according to this deviation, a first feedback gain is set at a determinating device F. In addition, a second feedback gain is set at a determinating device H on the basis of output of an engine load detecting device G. And, on the basis of the aforesaid deviation and both first and second feedback gains, a feedback controlled variable is set at a determinating device I, and a solenoid valve K is controlled via a feedback controlling device J in conformity with this controlled variable.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (a) Field of Industrial Application The present invention relates to a lock-up mechanism control device for a transmission.

(B) Prior Art A conventional lock-up mechanism control device for a transmission is disclosed in Japanese Patent Application Laid-Open No. 59-217056.

The lock-up mechanism of this transmission is configured to engage and release the lock-up mechanism of the fluid transmission device using a solenoid valve whose duty ratio is controlled. When the lock-up mechanism is engaged, the duty ratio of the solenoid valve is feedback-controlled so that the difference in rotational speed between the input side and the output side of the fluid transmission device changes according to a preset target value. This allows the lock-up mechanism to be smoothly fastened.

(C) Problems to be Solved by the Invention However, in the conventional lock-up mechanism control device as described above, the feedback control gain is constant, so the difference in engine load may cause the lock-up mechanism to engage. The problem is that time changes.

For example, if the gain is set so that a shock does not occur when the lock-up mechanism is engaged when the engine load is low, when the engine load is large, the time required to close the lock-up mechanism becomes longer and the durability of the lock-up mechanism decreases. . On the other hand, if the gain is set to provide an appropriate engagement time when the engine load is high, a lock-up mechanism engagement shock will occur when the engine load is low. The present invention aims to solve these problems.

(d) Means for Solving the Problems The present invention solves the above problems by changing the feedback control gain when the lock-up mechanism is engaged in accordance with the engine load. That is, the lock-up mechanism control device for a transmission according to the present invention includes an engine load detection means for detecting the load state of the engine, an input side rotation speed detection means for detecting the input side rotation speed of the fluid transmission device, and a fluid transmission device. output side rotation speed detection means for detecting the output side rotation speed of the output side rotation speed detection means, and calculates the difference between the input rotation speed detected by the input side rotation speed detection means and the output rotation speed detected by the output side rotation speed detection means. A rotational speed difference calculation means, a target rotational speed difference setting means for setting a target value of the rotational speed difference in advance, and an actual value of the rotational speed difference calculated by the rotational speed difference calculation means and the target rotational speed difference setting means. a first feedback gain determining means for determining a first feedback gain based on the deviation calculated by the deviation calculating means; and an engine load detecting means. second feedback gain determining means for determining a second feedback gain based on the calculated engine load; and determining a feedback control amount based on the deviation calculated by the deviation calculating means, the first feedback gain, and the second feedback gain. It has a feedback control amount determining means, and a feedback control means for controlling the operation of the solenoid valve based on the feedback control amount determined by the feedback control amount determining means.

(E) Effect The first feedback gain is in response to the slip speed deviation of the fluid transmission device, and the second feedback gain is in response to the engine load.
Since the 7-note hack control amount is determined by 18 points, the larger the deviation of the sliding speed, the more
Furthermore, the larger the engine load, the larger the feedback control amount. As a result, for example, if the setting is made so that no shock occurs when the lock-up mechanism is engaged when the engine load is low, when the engine load is large, the feedback control amount will increase and the lock-up mechanism will be engaged in a relatively short time. Therefore, the lock-up mechanism can be appropriately controlled whether the engine load is large or small.

(F) Embodiment FIG. 2 shows a power transmission mechanism of a continuously variable transmission. This continuously variable transmission has a fluid coupling 12 and a forward/reverse switching mechanism 15.
, ■ It has a belt type continuously variable transmission mechanism 29, a differential device 56, etc., and converts the output of the engine 10 @ 10 a rotation into outputs 1IIllI66 and 68 at a predetermined gear ratio and rotation direction.
can be transmitted to. This continuously variable transmission includes a fluid coupling 12 (including a lock-up oil chamber 12a, a pump impeller 12b, a turbine runner 12c, etc.), a rotating shaft 13, a drive shaft 14, a forward/reverse switching mechanism 15, and a drive pulley IS ( Fixed conical plate 18, drive pulley cylinder chamber 20 (chamber 20a, chamber 20b), movable conical plate 22, groove 22a, etc.), planetary gear mechanism 17 (sun gear 1
9, consisting of a pinion gear '21, a pinion gear 23, a pinion carrier 25, an internal gear 27, etc.), ■
Belt 24, driven pulley 26 (consisting of fixed conical plate 30, driven pulley cylinder chamber 32, movable conical plate 34, etc.)
, driven shaft 28, forward clutch 40, drive gear 46, idler gear 48, reverse brake 50, idler shaft 52
, a pinion gear 54, a final gear 44, a pinion gear 58, a pinion gear 60, a side gear 62, a side gear 64, an output shaft 66, an output shaft 68, etc., but a detailed explanation of these will be omitted. In addition,
The structure of the parts whose explanation is omitted is described in Japanese Patent Application No. 1982-226706 filed by the present applicant.

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, speed change motor (step motor) 110, speed change operation mechanism 112, throttle valve 114, constant pressure pressure adjustment button t-
116, solenoid valve 118, coupling pressure regulating valve 120,
It has a lock apple control valve 122, etc., which are connected to each other as shown in the figure, and also includes a forward clutch 40, a reverse brake 50, and a fluid coupling 1.
2. Lock-up oil chamber 12a, drive pulley cylinder chamber 2
0 and the driven pulley cylinder chamber 32 as shown. A detailed explanation of these valves and the like will be omitted.

For the parts omitted from explanation, please refer to the above-mentioned patent application 1986-22.
No. 6706. In addition, each reference numeral in FIG. 3 indicates the following members. Pinion gear 110a, tank 130, strainer 131, oil passage 132, relief valve 1
33, Methole 134, Port 134aNe, Spool 1
36, lands 136a-b, oil passage 138, one-way orifice 139, oil passage 140, oil passage 1'42, one-way orifice 143, valve hole 146, port 146aNg, spool 148, land 148a''-e, sleeve 150,
Spring 152, spring 154, pressing member 158
, oil passage 164, oil passage 165, orifice 166, orifice 170, valve hole 172, port 172aNe, spool 174, runt 174aA-rc, spring 175
, oil passage 176, orifice 177, lever 178, oil passage 179, pin 181, lot 182, land 182a~
b, rack 182c.

Pin 183, pin 185, valve hole 186, port 186
a Nd, oil path 188, oil path 189, oil path 190, valve hole 192, ports 192a-g, spool 194, lands 194a-e1 negative pressure diaphragm 198, orifice 1
99, orifice 202, orifice 203, valve hole 20
4. Port 204a-e1 spool 206, land 20
6aNb, spring 208, oil passage 209, -7. Old Kawa 11 Su1177 and 216. Port 222, solenoid 224, plunger 224a, spring 225,
Valve hole 230, port 230aNe, spool 232, lands 232a-b, spring 234, oil path 235, orifice 236, valve hole 240, ports 240a-h
, spool 242, lands 242a-e, oil passage 243
, oil passage 245, orifice 246, orifice 247,
Orifice 248, orifice 249, choke Jf throttle valve 250, relief valve 251, choke type throttle valve 252, holding pressure #253, oil passage 254, cooler 25
6. Cooler pressure holding valve 258, orifice 259, changeover detection switch 278. FIG. gear shift + td
The control device 300 includes a human power interface 311, a reference pulse generator 312, and a CPU (central processing unit) 313.
, ROM (read only memory) 314, RAM (
(b) Tam access memory) 315 and an output interface 316, which are connected to the address bus 31.
9 and data bus 320. This shift control device 300 includes an engine rotation speed sensor 3.
01, vehicle speed sensor 302, throttle opening sensor 3
03, shift position switch 304, turbine rotation speed sensor 305, engine coolant temperature sensor 306
, brake sensor 307 and changeover detection switch 298
The signal from the waveform shaper 308, 309 and 3
22, and an AD converter 310, while a signal is output to the step motor 110 through an amplifier 317 and lines 317a-d, and a signal is also output to the solenoid 224, but a detailed explanation of these will be omitted. . The structure of the parts whose explanation is omitted is described in the above-mentioned Japanese Patent Application No. 59-226706.

Next, the details of the specific control of the solenoid 224 performed by the shift control device 300 will be explained.

The lj control circuit for step motor 110 and solenoid 224 is shown in FIGS. 5 and 6. First, the shift position is read from the shift position switch 304 (step 502), and it is determined whether the shift position is in the driving position (ie, D, L or R range). is solenoid 22
The duty ratio of 4 is set to 0 (506), and the process proceeds to step 630, which will be described later. When the shift position is in the driving position, the throttle opening TH is read from the throttle opening sensor 303 (50B>, the vehicle speed sensor 302
The vehicle speed V is read from the engine rotation speed sensor 301 (510), the engine rotation speed NE (input side rotation speed of the fluid transmission device) is read from the engine rotation speed sensor 301 (512), and the turbine rotation speed N is read from the turbine rotation speed sensor 305.
t (output side rotational speed of the fluid transmission device) is read (step 514). Next, the rotational speed difference N between the engine rotational speed Nε and the turbine rotational speed Nt. Calculate the same 516
), then the lock-up-on vehicle speed V. N and lock-up-off vehicle speed V OFF are searched (518). Lock-up on vehicle speed ■. N and lock-up-off vehicle speed V
For OFF, characteristics such as those shown in FIG. 7 are stored as functions of vehicle speed V and throttle opening TH. Next, it is determined whether the lock-up flag LUF is set (520), and if the flag LUF is not set, it is determined whether the actual vehicle speed is greater than the lock-up on vehicle speed VoN. 522),
In the case of V>Vo, 4, N□-Nm is set as the deviation e (524). Note that Nm is a target value of the rotational speed difference between the engine rotational speed NE and the turbine rotational speed Nt. Next, the first feedback gain G1 is searched based on the value of the deviation e (2001). The deviation e and the first feedback gain Gl have a relationship as shown in FIG. 8, for example. Next, throttle opening T
The second feedback gain G2 is searched based on the value of H (2003). The relationship between the throttle opening TH and the 27th gain G is as shown in FIG. 9, for example. Next, it is determined whether No is smaller than a predetermined small value No (528). N
O is a rotational speed difference at which feedback control is performed when N o- is larger than this, and feedforward control is performed when it is smaller than this. N,
<If No, set the value obtained by adding a small value α% to the current duty ratio as the new duty ratio.
0), then it is determined whether the duty ratio is smaller than 100% (532), and if it is smaller than 100%, the process proceeds to step 602, which will be described later.On the other hand, if it is 100% or more, the duty ratio is set to 100%. 534), then set the lockup flag LUF (536),
Similarly, the process proceeds to step 602, which will be described later (that is, feedforward control is performed). Step 5 above
If N0≧No in 28, the duty ratio is determined based on the deviation e, the first feedback gain GI, and the second feedback gain G2.
The process advances to step 602 (ie, feedback control is performed). Also, in step 522 described above, ■≦VOH
In this case, the duty ratio is set to 0% (540),
Next, clear the lockup flag LUF (542
). This releases the lock-up mechanism. Also, in step 520 described above, the lockup flag L
If UF is set, it is determined whether the vehicle speed V is smaller than the lock-up off vehicle speed VOFF.
), steps 540 and 542 if V<VOFF
Proceed to (lock-up release), and if V≧V OFF, set the duty ratio to 100% (546)
(This maintains the lockup state).

The steps 502 to 546 described above result in uniform control. That is, the lock-up mechanism is always released when the shift position is in the P and N positions other than the driving position (step 506), and when the shift position is in the driving position, the lock-up mechanism is set at a predetermined lock-up-off vehicle speed Vo,
In the above cases, the lock-up state is maintained (step 546), and the lock-up off vehicle speed is maintained. FF
At lower vehicle speeds, the lock-up mechanism is deactivated (step 540), and when the lock-up mechanism switches from a non-activated state to an activated state, feedback control is performed according to the amount of slippage of the fluid coupling 12 (step 2005). Alternatively, the lock-up mechanism is smoothly engaged by feedforward control (step 530). When feedback control is performed, the feedback control amount is determined based on the deviation e, the first feedback gain Gl, and the second feedback gain G2 (for example, e, Gl, and G2 are multiplied by a constant and added). ), so in addition to the feedback control amount changing depending on the size of the deviation e, the throttle opening TH (
In other words, it changes depending on the engine load. Therefore, when the engine load is low, feedback control is performed slowly, and when the engine load is high, feedback control is performed rapidly. As a result, the lock-up clutch can always be appropriately engaged regardless of changes in engine load.

Note that the control from step 602 onward shown in FIG. 6 is not directly related to the present invention, and therefore a description thereof will be omitted.

(g) As described in detail, according to the present invention, the feedback control amount when the lock-up mechanism is engaged is changed in accordance with the engine load, so that it can be maintained in an appropriate state regardless of the magnitude of the engine load. The lock-up mechanism can be engaged, and it is possible to prevent the occurrence of a shock at the time of engagement and a decrease in the durability of the lock-up clutch.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the relationship between the constituent elements of the present invention, Fig. 2 is a diagram showing the power transmission mechanism of a continuously variable transmission, and the fourth section is ##-control table, which shows the control table. Section 6 shows the control routine of the transmission control device, and FIG. 7 shows lock-up-off vehicle speed and lock-up. FIG. 8 is a diagram showing the relationship between the deviation and the first feedback gain, and FIG. 9 is a diagram showing the relationship between the throttle opening and the second feedback gain. 12...Fluid coupling (fluid transmission device), 1
10... variable speed motor (step motor), 118...
- Solenoid valve, 122...Lockup control valve.

Claims (1)

[Scope of Claims] A lock-up mechanism control device for a transmission having a fluid transmission device equipped with a lock-up mechanism whose engagement state is controlled by a solenoid valve, comprising: engine load detection means for detecting a load state of an engine; An input side rotation speed detection means for detecting the rotation speed on the input side of the transmission, an output side rotation speed detection means for detecting the rotation speed on the output side of the fluid transmission device, and an input detected by the input side rotation speed detection means. rotation speed difference calculation means for calculating the difference between the rotation speed and the output rotation speed detected by the output side rotation speed detection means; target rotation speed difference setting means for setting a target value of the rotation speed difference in advance; a deviation calculating means for calculating the deviation between the actual value of the rotational speed difference calculated by the calculating means and the target value of the rotational speed difference set by the target rotational speed difference setting means; and a deviation calculating means based on the deviation calculated by the deviation calculating means. a first feedback gain determining means for determining the first feedback gain based on the engine load detected by the engine load detecting means; a second feedback gain determining means for determining the second feedback gain based on the engine load detected by the engine load detecting means; feedback control amount determining means for determining the feedback control amount based on the deviation, the first feedback gain, and the second feedback gain; and controlling the operation of the solenoid valve based on the feedback control amount determined by the feedback control amount determining means. 1. A lockup mechanism control device for a transmission, comprising: feedback control means for controlling a transmission lockup mechanism.