JPS61206860A - Speed change controller for transmission - Google Patents

Abstract

PURPOSE:To improve speed change control by correcting a prescribed speed change instruction signal only in the case when a throttle is perfectly closed within a prescribed time after the reduction speed of the throttle opening-degree corresponding signal becomes over a judgment value determined according to the operation condition immediately before the start of closing operation. CONSTITUTION:When the throttle opening-degree 303 is reduced according to the step motor-control routine accommodated into the CPU 313 of a speed change controller 300, and the quantity of variation of the turottle opening- degree 303 is larger than a prescribed quantity, and a throttle is perfectly closed within a prescribed time, speed change control is carried-out on the basis of the L-range speed change pattern even if the shift position 304 is in D-range. Therefore, speed change ratio can be favorably controlled, and the operation of engine brake over necessary quantity can be prevented.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to a speed change control device for a transmission.

(B) Conventional technology As a conventional speed change control device for a transmission, for example,
There is one shown in Japanese Patent No. 8-203258. The speed change control device of this transmission is configured to control when the slow/torque opening changes to the fully closed state at a speed higher than a predetermined speed (i.e., when the accelerator pedal is quickly returned from the depressed state), the desired deceleration is adjusted. Therefore, the gear shift command signal is modified so as to obtain a relatively large gear shift (in other words, the gear ratio is set to a value that is somewhat larger than the minimum gear ratio). ratio, and an engine braking effect can be obtained.

(c) Problems to be Solved by the Invention However, the conventional speed change control device for a transmission as described above has the following problems. In other words, control is performed to shift the gear ratio to the larger side based only on the speed at which the throttle opening decreases, so even if the amount of change in the throttle opening is small, the speed of change is fast (for example, when the accelerator pedal is slightly depressed) (in the case where the driver steps on the pedal and immediately returns the pedal), control is performed to shift the gear ratio to the larger side, resulting in a state in which engine braking is applied more than necessary. Additionally, if a dashpot is provided to control the return state of the throttle to control the state of engine exhaust gas, the operation of the dashpot changes depending on the operating state of the engine.
Even though the driver requests the engine braking effect to occur, the gear ratio may not be shifted to the larger side.

The present invention aims to solve the above problems.

(d) Means for solving the problem The present invention determines whether to perform control to shift the gear ratio to the large side based on the operating conditions immediately before the throttle closing operation is started. This solves the above problems. That is, the speed change control device for a transmission according to the present invention includes a throttle closing operation detection means for detecting that a throttle closing operation has started, and a throttle opening corresponding to at least a signal immediately before the throttle closing operation is started. a determination value determining means for determining a determination value of the rate of change of the throttle opening corresponding signal; a throttle change speed determining means for determining that the rate of change of the throttle opening corresponding signal in the throttle closing direction is equal to or higher than the determination value;
Downshift means for modifying the shift command signal so that a predetermined deceleration is obtained only when the throttle is fully closed within a predetermined time after it is determined that the rate of change in the throttle closing direction is equal to or greater than the above-mentioned determination value. It has . Note that although the embodiments described below will be described with reference to a continuously variable transmission, the present invention can also be applied to a stepped automatic transmission having a downshift means.

(E) The action determination value determining means determines a larger determination value as the throttle opening degree immediately before the start of the throttle closing operation is smaller. Since the downshift means does not operate unless the throttle change speed exceeds this determination value, if the throttle opening degree immediately before the start of the throttle closing operation is small, control to shift the gear ratio to the large side becomes difficult to perform. Therefore, for example, when the accelerator pedal is slightly depressed or released in order to follow a vehicle in front while driving in a city area, unnecessary activation of the engine brake is prevented. In addition, if the throttle is not fully closed within a predetermined time after the throttle change speed exceeds the threshold, the downshift means will not work. Even if the speed of change of the throttle exceeds the determination value, if the throttle is then returned slowly, control to shift the gear ratio to the large side will not be performed.
Unnecessary application of engine braking is "prevented." Also, even if the throttle is not returned quickly due to the action of the dashpot installed on the engine,
If the throttle opening is large just before the start of the throttle closing operation, the leaf judgment value becomes small, so the throttle change speed easily becomes larger than the judgment value, and the downshift means acts to shift the gear ratio to the large side. Therefore, the engine braking effect can be obtained under driving conditions where the driver requires engine braking.

(f) Embodiment FIG. 2 shows the power transmission mechanism of a continuously variable transmission.
, (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 IO to the output shafts 66 and 68 at a predetermined gear ratio and rotation direction. This continuously variable transmission uses fluid coupling 1
2 (lock-up oil chamber 12a, pump impeller 12
b, has a turbine runner 12c, etc.).

Rotating shaft 13, drive shaft 14, forward/backward switching mechanism 15° drive pulley 16 (fixed conical plate 18, drive pulley cylinder chamber 2)
0 (chamber 20a, chamber 20b), movable conical plate 22. Groove 2
2a, etc.), planetary gear mechanism 17 (sun gear 19,
Pinion gear 21. Pinion gear 23, pinion carrier 25. (consisting of an internal gear 27, etc.), (2) a belt 24, and a driven pulley 26 (consisting of a fixed conical plate 30, a driven pulley cylinder chamber 32, a movable conical plate 34, etc.);

Driven shaft 28. Forward clutch 40. Drive gear 46, idler gear 48, reverse brake 50. Idler shaft 52.
Binion gear 54% Final gear 44, Pinion gear 58. Pinion gear 606, side gear 62. It is composed of 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 omitted parts is described in Japanese Patent Application No. 59-226706 filed by the present applicant.

FIG. 3 shows a hydraulic control device for a continuously variable transmission. This hydraulic control device includes an oil pump lot, 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 regulating valve 11
6, a solenoid valve 118, 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.
．． It is also connected to a reverse brake 50, a fluid canopy ring 12, a lock-up oil chamber 12a, a driving pulley cylinder chamber 20, and a 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, valve hole 134, port 134aNe, spool 13
6. Lands 136a-b, oil passage 138, one-way orifice 139, oil passage 140, oil passage 142, one-way orifice 143° valve hole 146. bow) 146aNg, spool 1
48, land 148a Ne, sleeve 150, spring 152. Spring 154. Pressing member 158, oil passage 164. Oil passage 165, orifice 166, orifice 1
70, valve hole 172% port 172a-e, spool 17
4. Lands 174a to C, springs 175, oil passages 17
6, orifice 177, lever 178, oil passage 179. Pin 181, rod 182. Land 182a Nb% rack 182c, pin 183, pin 185, valve hole 186, ports 186a to d, oil path 188, oil path 189% oil path 1
90. Valve hole 192, ports 192a-g, spool 19
4, land 194 a #e, negative pressure diaphragm 19
8. Orifice 199, orifice 202, orifice 203, valve hole 204, port 204a-e, spool 2
06. Lands 206a-b, spring 208, oil path 2
09° filter 211. Orifice 216, port 2
22, solenoid 224. Plunger 224a.

Spring 225, valve hole 230. Port 230a~e%
Spool 232. Lands 232a-b, springs 23
4, oil passage 235, orifice 236, valve hole 240, port 240a-h, spool 242, land 242a-e
, oil passage 243, oil passage 245, orifice 246, orifice 247, orifice 248. Orifice 249, choke type throttle valve 250, relief valve 251, chi-weight type throttle valve 252, pressure holding valve 253. Oil passage 254° Cooler 256, Cooler pressure holding valve 258, Orifice 259
．． The shift control device 51300 shows the shift control device 300 that controls the operation of the step motor 110 and the solenoid 224 at the 41i11th position.The shift control device 51300 includes an input interface 311, a reference pulse generator 312,
PU (Central Processing Unit) 313, ROM (Read Only Memory) 314, RAM (Random Access Memory) 3
15 and an output interface 316, which are communicated by an address bus 319 and a data bus 320. This speed change control device 300 includes:
Engine speed sensor 3゜1, vehicle speed sensor 302
, throttle opening sensor 303. Shift position switch 304, turbine rotation speed sensor 305, engine coolant temperature sensor 306, brake sensor 307
and the signal from the changeover detection switch 298 is transmitted directly or to the waveform shapers 308, 309 and 322, and the AD converter 31.
0, while intensifier 317 and line 317a
A signal is output to the step motor 110 through -d,
Further, signals are also output to the solenoid 224, but a detailed explanation of these will be omitted. The structure of the parts whose explanation is omitted can be found in the above-mentioned Japanese Patent Application No. 59-2267.
It is described in No. 06.

5 to 7 show the control contents performed by the transmission control device 300. Of these, the complete engagement control of the clutch by controlling the solenoid 224 and the lock-up control of the fluid coupling 12 are described in the above-mentioned patent application No. 5.
Since it is the same as that described in No. 9-228706, the explanation will be omitted.

A step motor control routine is shown in FIGS. 6 and 7. If the actual vehicle speed V is greater than a predetermined small value Vo in step 602, the process proceeds to step 624, where it is determined whether the shift position is in the D range, and if the shift position is not in the D range, the process proceeds to step 639, In the case of the range, the process proceeds to step 902 and subsequent steps. In step 902, it is determined whether the flag ENB is set. If it is not set, the throttle opening TH' in the previous routine (this is shown in FIG. 5) is determined. Step 507
The difference ΔTH between the previous throttle opening (set the previous throttle opening for each routine) and the throttle opening TH of the current routine
(step 904), then the calculated ΔT
Determine whether H is a positive value (that is, whether the throttle opening is decreasing) (906);
If ΔTH is positive, it is determined whether ΔTH is larger than a predetermined value ΔTHo (908).
If it is larger than Ho, search for the judgment value ΔTHh0
The judgment value ΔTHh is a predetermined value of the characteristics shown in FIG.
(In this example, the judgment value ΔTHh can be set corresponding to the throttle opening and vehicle speed, but it is also possible to set the judgment value ΔTHh corresponding to only the throttle opening.) However, the search criterion for the throttle opening is THs is used as the value. This TH
s is the one stored in step 912. That is, if ΔTH is 0 or negative in step 906, or if ΔTH is less than ΔTHO in step 908, TH-t at that time is set as THs in step 912.

From step 912, the process advances to step 914 where flag E is set.
Settle NB and proceed to step 924. After searching for ΔTHh in step 910 described above, ΔTH is equal to this judgment value Δ
To judge whether it is larger than THh (916), Δ
If TH is larger than the judgment value ΔTHh, flag EN is set.
918), and the timer value Tx is "rt".
(920), while in step 916 ΔT
If H is less than the judgment value ΔTHh, the step 9 described above is performed.
Proceed to step 14.

If the flag ENB is set in step 902 described above, it is determined whether the idle switch is on (step 926). Note that the idle switch is activated when the accelerator pedal depression amount is Ol, that is, when the throttle is fully closed. This is a switch that is turned on. If the idle switch is on, the flag L is set (928) and the process proceeds to step 924. If the idle switch is off, it is determined whether the timer value Tx is 0 (930), which is not O. In this case, the value obtained by subtracting 1 from Tx is set as the new Tx (932), and Tx=
If it is 0, the flag ENB is cleared (934) and the process proceeds to step 924.

In step 924, it is determined whether the flag L is set, and if it is set, it is determined whether the idle switch is on (936), and if the fiddle switch is off, the timer value Ty is determined. Step 62
Proceed to step 6 to search for the D range shift pattern, and
Even if the flag L is not set in step 924, the process proceeds to step 626. If the idle switch is on in step 936, T2 is set as the timer value Ty (942), and the process proceeds to step 628. Search for the L range shift pattern, and step 9
If TV is not 0 at step 38, 1 is subtracted from the TV value and this is set as a new TV value (944), and the process proceeds to step 628 to search for an L range shift pattern.

As a result, the throttle opening is reduced by the above control routine (step 906→step 90g), and the amount of change in the throttle opening is larger than the predetermined value (step 9).
16→Step 918) and the throttle is fully closed within the predetermined time (T'l) (Step 926→Step 928), even if the shift position is in the D range, the shift pattern will be changed based on the L range shift pattern. L is where the gear change control is performed (step 942→step 628).
Since the range shift pattern is set so that the gear ratio is larger than that of the D range shift pattern, the gear ratio shifts to the large side. In case of operating conditions other than the above,
In other words, if the throttle opening is not decreasing, if the rate of decrease in the throttle opening is less than or equal to the threshold value, or if the throttle is not fully closed within a predetermined time Tx after the rate of decrease in the throttle opening exceeds the threshold value, If the shift position is in the D range, driving is performed according to the D range shift pattern (step 626), and when the shift position is in the L range, the shift is performed according to the L range shift pattern (step 624 → step 639 → (step 628), and the determination value ΔTH in step 910
As mentioned above, the data of h is stored in correspondence with the throttle opening and vehicle speed, and the value of TH for searching is the value THs (step 9) immediately before the throttle opening starts decreasing.
12), it is possible to perform control to increase the gear ratio for engine braking in an optimal state corresponding to the operating conditions. In other words, if the throttle opening is small just before the start of the throttle closing operation, the judgment value will be large, making it difficult to control the gear ratio to a large side, and causing engine braking to be applied more than necessary due to a slight throttle operation. This can be prevented. Furthermore, even if the engine throttle is provided with a dashpot, if the throttle is fully closed within the predetermined time Tx, the engine brake will be applied, so that the vehicle will be driven in accordance with the driver's intentions. In addition,
The timer Ty set in step 942 is used to delay the speed ratio by 12 hours and return the gear ratio to the normal state when the accelerator pedal is pressed again. This prevents engine torque fluctuations and transmission gear changes from being synchronized.

(g) As described in detail, according to the present invention, the determination value is determined according to the operating conditions immediately before the start of the throttle closing operation, and the reduction rate of the throttle opening corresponding signal is determined.

The speed change command signal is modified so that the specified deceleration is obtained only when the throttle is fully closed within a specified time after the accelerator pedal speed reaches or exceeds this judgment value. If the gear ratio is immediately returned to the original position, control to shift the gear ratio to the larger side is not performed, which prevents engine braking from being applied more than necessary and provides a suitable driving feeling. Even when the dashpot of the vehicle is controlled according to the driving conditions, the gear shift can be performed in accordance with the driver's intention.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the relationship between the constituent elements of the present invention, the second factor is a diagram showing a sectional view of the continuously variable transmission, Fig. 3 is a diagram showing the hydraulic control device of the continuously variable transmission, and Fig. 4 is a diagram showing a speed change control device,
s5.6 and 7 are diagrams showing the speed change control routine, and FIG. 8 is a diagram showing characteristics of determination values.

Claims (1)

[Scope of Claims] In a speed change control device for a transmission that controls speed change based on an electrical signal corresponding to a throttle opening degree and other signals, a throttle closing operation detection means detects that a throttle closing operation has been started. a determination value determining means for determining a determination value of the rate of change of the throttle opening corresponding signal based on at least the throttle opening corresponding signal immediately before the throttle closing operation is started; Throttle change speed determining means for determining that the speed of change is greater than or equal to the above-described determination value, and when the throttle is fully closed within a predetermined time after it is determined that the rate of change in the throttle closing direction is equal to or greater than the aforementioned determination value. 1. A shift control device for a transmission, comprising: downshift means for modifying a shift command signal so that a predetermined deceleration is obtained only in