JPS61103048A - Controller for stepless speed changer - Google Patents

Abstract

PURPOSE:To prevent deterioration of control accuracy of rotary speed at the input side by setting predetermined difference between input side rotary speed and target speed as a function of intake throttle opening. CONSTITUTION:Outputs from input side rotary speed sensor 363 and target input side rotary speed calculating means 365 are fed to difference calculating means 366 the output of which is fed together with the output from predetermined level calculating means 368 to case detecting means 370 thus to set predetermined difference between the target input side rotary speed and the input side rotary speed as a function of intake throttle opening. Since variation of input side rotary speed within response delay under switching of changing speed will be such level as corresponding with the magnitude of target input side rotary speed and the input side rotary speed, the input side rotary speed can be controlled will irrespectively of the intake throttle opening and response delay due to switching of speed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application: The present invention relates to a control device for a continuously variable transmission for a vehicle (hereinafter referred to as "continuously variable transmission").

In the conventional technology CVT control device, the CVT gear ratio T (γ=Nin
/Nout: However, Nin+Nout are each CVT
are the input side rotation speed and the output side rotation speed. ) is C
Controlled by the inflow and outflow of hydraulic medium in one hydraulic cylinder of the VT, for example the input hydraulic cylinder,
In order to smoothly transition from the actual input side rotational speed Nin of the VT to the target input side rotational speed Nino, the input side oil pressure is set to 1 in relation to the 0 difference between Nino and Nin. :/f It is advantageous to control the speed of inflow and outflow of the hydraulic medium in the LCia, that is, the speed of the gear change, as described for example in Japanese Patent Application No. 58-203130.
In this issue, the inflow of hydraulic medium in the input hydraulic cylinder,
a first spool valve which switches the supply of hydraulic medium to the input hydraulic cylinder and the discharge of the hydraulic medium from the input hydraulic cylinder by means of a control pressure controlled by a first solenoid valve; and a second spool valve that controls the flow passage cross-sectional area between the input side hydraulic cylinder and the first spool valve by the control pressure controlled by the second solenoid valve, and the target input side rotational speed Nino and A predetermined value is set for the difference ΔNin from the actual input side rotational speed Nin, and when 1 mm Nin l changes from a value greater than the predetermined value to a value smaller than the predetermined value, the flow rate in the second spool valve is switched from a large value to a small value. There is.

There is a response delay in switching the flow rate at the second spool valve, and the shift width of the CVT within this response delay is constant regardless of the intake throttle opening θ, whereas the actual input side rotational speed Nin and the target 1 input end rotation speed Ni
Since no increases as the intake throttle opening increases, the amount of change in the input side rotational speed Nin during response pain increases as the intake throttle opening e increases. In conventional control devices, the above-mentioned predetermined value regarding the difference between Nino and Nin is fixed, so if this predetermined value is adapted when the intake throttle opening θ is small, Nin when the intake throttle opening θ is large. will greatly exceed Nino, and conversely, if this predetermined value is applied when the intake throttle opening θ is large, there will be a problem that Nin will be delayed in approaching Nino when the intake throttle opening θ is small. be.

Problems to be Solved by the Invention An object of the present invention is to provide a CVT control device that can prevent a decrease in the accuracy of input side rotational speed control due to a response delay when switching the CVT transmission speed. It is.

Means for Solving the Problems In order to achieve this object, according to the present invention, the transmission mechanism of the CVT is controlled by the inflow and outflow of hydraulic medium in one hydraulic cylinder of the CVT, and the actual input side rotation of the CVT is The gear ratio T of the CVT is controlled so that the speed Nin becomes the target input side rotational speed Nino, a predetermined value is set for the difference between the target input side rotational speed Nino and the actual input side rotational speed Nin, and the hydraulic cylinder In a control device for a vehicle CVT in which the inflow and outflow speeds of hydraulic medium are controlled in relation to a comparison result between the difference and the predetermined value, the predetermined value is set as a function of an intake throttle opening degree. .

Effects of the Invention As a result of the fact that the predetermined value of the difference between Nino and Nin when the speed of inflow and outflow of the hydraulic medium in one hydraulic cylinder of the CVT, that is, the shift speed is switched, is set as a function of the intake throttle opening θ, The amount of change in the input side rotational speed Nin within the response delay when changing the gear speed is Nin+N
This is an appropriate value depending on the size of ino. In this way, the input side rotational speed Nin can be well controlled regardless of the intake throttle opening degree, despite the delay in response when changing the speed change speed.

Preferably, the hydraulic cylinder is an input-side hydraulic cylinder, and the inflow and outflow speeds of the hydraulic medium in the input-side hydraulic cylinder are switched depending on the target input-side rotational speed and the actual speed.

In addition, the inflow and outflow of the hydraulic medium in the input hydraulic cylinder and their speeds are controlled by the control pressure controlled by the first solenoid valve. The control pressure controlled by the first spool valve that switches the discharge of the hydraulic medium and the second solenoid valve connects the input hydraulic cylinder to:
The second spool valve controls the cross-sectional area of the flow path between the first spool valve and the first spool valve.
may be controlled by a spool valve.

Example The present invention will be described in detail with reference to the drawings.

In Fig. 2, CVT I is a pair of input sheaves 2a.
+2b, I pair of output-side sheaves 4a+4b, and a belt 6 that is hung over the input-side and output-side sheaves to transmit engine power. One input side sheave 2a is the input shaft 8
The input sheave 2b is provided movably in the axial direction and fixed in the rotational direction, and the other input side sheave 2b is fixed to the input shaft 8. Further, one output side sheave 4a is fixed to the output shafts 1, 0, and the other output side sheave 4b is provided on the output shaft 10 so as to be movable in the axial direction but fixed in the rotational direction. Opposing surfaces of input side sheaves 2a and 2b and output side sheave da
, 4b are formed in a tapered shape such that the distance between them increases toward the outside in the radial direction, and the cross section of the belt 6 is formed in the shape of an isosceles trapezoid. The pressing force of the output side sheaves 4a + 4b is set to the minimum value that can avoid muddying of the belt 6 and ensure power transmission, and the pressing force of the input side sheaves 2a, 2b is set to the CVT l's transmission modification (= input shaft 8). Rotational speed N
in/rotational speed Nout of the output shaft lO) is determined. The fluid coupling 12 is a pump connected to the crankshaft 14 of Tonoseki! 6, and a turbine 18 which is rotated by oil from the pump 16 and is fixed to the input shaft 8. The lock-up clutch 22 controls the connection between the crankshaft 14 and the input shaft 8, and the damper 24 absorbs shock and engine torque fluctuations when the lock-up clutch is switched from a disengaged state to an engaged state. When the vehicle speed or engine rotational speed exceeds a predetermined value, the lock-up clutch 22 is held in an engaged state to avoid loss of power transmission due to oil in the fluid coupling 12. The oil pump 26 rotates integrally with the pump 16 and sends oil to the CVT I, the fluid coupling 12, etc. via a hydraulic control device. The counter shaft 28 is provided parallel to the output shaft IO of the CVT I and has two gears 30, 32. The engine power of the output shaft 10 is generated by a gear 3 coaxial with the output shaft 10.
4 to the differential gear 36 via gears 30, 32 on the countershaft 28, and further from the differential U36 to the left 6 driving NJ wheels via the left and right axles 38,40. Sub-transmission 42 is CVT! It is provided coaxially with respect to the output axis lO of.

The auxiliary transmission fi 42 includes a Ravigneau type compound planetary gear set 43, and this planetary gear set 43 includes first and second sun gears 44, 46, a first planetary gear 48 that meshes with the first sun gear 44, and this first planetary gear. 48 and second planetary gear 5 meshing with second sun gear 46
0, a ring gear 52 that meshes with the first planetary gear 48, and the first and second planetary gears 48, 5
0 rotatably supported.

The second sun gear 46 is the output shaft of the CVT l as the input part of the sub-transmission 42! 0 and is connected to a shaft 64 integral with
Carrier 54 is I! Connected to li+*34. The high speed clutch 56 controls the connection between the shaft 64 and the first sun gear 44, and the low speed brake 58 controls the connection between the shaft 64 and the first sun gear 1.
4, and the reverse brake 60 is connected to the ring gear 5.
Controls the fixation of 2.

FIG. 3 shows the operating state of each frictional engagement element of the auxiliary transmission 8!42 and the reduction ratio in each range. ◯ means an engaged state, × means a released state, and pl and ρ2 are defined from the following equation.

p I = Zsl /Zr - p2 = Zs2/Zr where Zsl is the number of teeth of the first sun gear 44, Zs2 is the number of teeth of the second sun gear 46, and Zr is the number of teeth of the ring gear 52. In other words, the low-speed engine gear clutch 56 in the D range is engaged and the planetary gear unit 43 rotates together, thereby transmitting engine power at a reduction ratio of 1, and in the R range, the reverse brake is engaged. Ring gear 5 by 60
2 is fixed, engine power is transmitted through reverse rotation with a reduction ratio of 1-1/p2.

4 to 6 are detailed views of the hydraulic control device. The oil pump 26 pressurizes the oil sucked in through the strainer 72 and supplies it to the line pressure oil path 74. The throttle valve 76 generates a throttle pressure pth related to the intake throttle opening θ to the output port door 8. The spool 77 of the throttle valve 76 receives an acting force that increases as the throttle opening θ increases from the throttle cam 79 and a throttle pressure pth as a feedback pressure from the control port 8I, and is connected to the line pressure oil path 74. Controls the connection with the output port door 8. The manual valve 80 is
Shift lever L (low), D (drive), N
The axial position is controlled in relation to the neutral), R (reverse), and P (parking) ranges, and the first line pressure PII of the line pressure oil passage 74 is sent to the boat 83 in the R range and to the boat 83 in the L range. leads to boat 85, and when in D range, leads to boat 85.87.

The relief valve 89 has n 617 as a safety valve that releases the oil in the line pressure oil passage 74 when the first line pressure P/I of the line pressure oil passage 74 exceeds a predetermined value.

The secondary hydraulic oil passage 82 has an orifice 84 and a boat 8 where excess oil from the primary regulator valve 198 is discharged.
The secondary pressure regulator valve 86 is connected to the line pressure oil passage 74 via the orifice 8.
A control chamber 9 connected to a secondary hydraulic oil line 82 via 8
0, and controls the connection between the secondary hydraulic oil passage 82 and the boat 94 in relation to the oil pressure in the control chamber 90 and the load on the spring 92;
The secondary hydraulic pressure Pz of the secondary hydraulic oil passage 82 is maintained at a predetermined value.

The lubricating oil passage 95 is connected to the secondary hydraulic oil passage 82 via a boat 94 or an orifice 97. The lock-up control valve 96 connects the secondary hydraulic oil passage 82 to the fluid clutch 12.
The lock-up clutch 22 is selectively connected to the engagement side and release side of the lock-up clutch 22 in parallel with the lock-up clutch 22 . 'Ft solenoid valve 100 controls the connection between the control chamber +02 of the lock-up control valve 96 and the drain 104, and when the solenoid valve +00 is off (de-energized), the secondary hydraulic oil path is connected to the release side of the lock-up clutch 98. The secondary hydraulic pressure Pz from 82 is transmitted, the engine power is transmitted via fluid clutch +2, and solenoid valve +00 is turned on (excitation ri!
t), the secondary hydraulic pressure Pz from the secondary hydraulic oil passage 82 is supplied to the engaged side of the lock-up clutch 98 and the oil cooler 106, and the wet power is transmitted via the lock-up clutch 98. Cooler bypass valve +07 controls cooler pressure.

The gear ratio control device 108 includes first and second spool holes O1 and 2, and first and second solenoid valves 114 and 116. The period during which the first solenoid valve port 4 is off is the first solenoid valve port 4.
The spool of the spool valve 110 is pressed toward the spring 8 by the secondary hydraulic pressure Pz of the chamber +17, and the spool of the spool valve 110 of the boat +1
9 first line pressure PI! I is the first spool valve +10
Boat! 20 to the boat + 22 of the second spool valve 112, and the boat! 24 and the drain 126 are disconnected. During the period when the first solenoid valve port 4 is on, the hydraulic pressure in the chamber 7 is discharged through the drain 128 of the first solenoid valve port 4, and the spool of the first spool valve , and the boat 120 has line pressure PI! , does not occur, and the boat 124 drains 1
26. Also, during the period when the second solenoid valve +16 is off, the spool in the second spool is in the chamber 128.
The secondary hydraulic pressure Pz pushes the spring 130 toward the boat! 22 and the boat 132 are connected, and the boat 13
4 is connected to boat +36. Boat 132.1
34 is connected to the input hydraulic cylinder of the CVT l via an oil passage 138. During a certain period when the electromagnetic field 6 of @2 is on, the hydraulic pressure in the chamber 128 is discharged from the drain 139 of the second electromagnetic valve 116, and the spool of the second spool valve 112 is moved toward the chamber +28 by the spring 130. When pressed, boat +22 is connected to boat 132, and boat 134 and boat 136 are disconnected.

Boat +36 is connected to boat 124 via oil line 142. The orifice 140 guides a small amount of oil from the boat +22 to the boat 132 when the second solenoid valve 6 is turned off. Hence the first solenoid valve! 14 is off and the second
During the period when the solenoid valve 116 is on, oil is promptly supplied to the input hydraulic cylinder of the CVT I.
The gear ratio T decreases. The first solenoid valve! During the period when 14 is off and the second solenoid valve 6 is off, oil is supplied to the input hydraulic cylinder of CVT '1 through orifice 140.
The gear ratio of CVT 1 is gradually lowered. When the first solenoid valve +14 is on and the second +4 solenoid valve 116 is on, oil is not supplied to or discharged from the input hydraulic cylinder of C, VT I, and the CVT
The gear ratio T of l is held constant. 1st @magnetic valve 11
4 is on and the second electromagnetic valve 116 is off, the oil in the input hydraulic cylinder 46 is further discharged to the drain 126, so the transmission speed of the CVT I increases rapidly.

The gear ratio detection valve 146 is shown in detail in FIG.

Sleeves 148 and 150 are valve holes! 52 and fixed in the axial direction by a snap ring 154. Rod 156 passes through the end of sleeve +48;
A spring seat 158 is fixed.

Another rod +60 is coupled at both ends to the input movable sheave 2a and the rod 156, respectively, and moves the rod 156 in the axial direction by a displacement equal to the axial displacement of the input movable sheave 2a. The spool 162 has run and do 164
, 166, and the sleeve! 50 so as to be movable in the axial direction.

Land +64 is the space 16 between lands 164 and 166
8 to the oil chamber 170, and the land 166 has a sleeve +50 boat 174 to the space +68.
control the aperture area. Boat 174 is sleeve 148
It is connected to the drain 176 through the space around the outer periphery of the drain 176.

The oil chamber 170 has an output port I78 that generates a control pressure Pc, and the output port +78 is connected to the line pressure oil passage 74 via an orifice 180. The spring 182 is provided between the spring receiver 158 and the sleeve +50 and is attached to the rod 156.
The spring 184
It is provided between the splash receiver 158 and the flange 186 of the spool 162 to bias the spool 162 toward the oil chamber 170. As the amount of displacement of the input side movable sheave 2a of the CVT 1 with respect to the input side fixed sheave 32 increases, the lower gear ratio increases. Since the rod +56 is pushed out of the sleeve 148 due to an increase in the amount of displacement of the input side movable sheave 2a, the urging force on the spool 162 by the spring 184 in the direction of the oil chamber 170 decreases.

Since the land +66 increases the opening area of the boat 174 and increases the oil discharge flow rate, the gear ratio pressure lamp of the output port 178 decreases and the gear ratio pressure P7 increases to the output boat +7.
Since it is generated by controlling the discharge amount of the hydraulic medium of 8, the upper limit is set to the line pressure P7! stipulated in The broken lines in FIGS. 8 and 9 illustrate two relationships between the gear ratio pressure and the gear ratio. As will be described later, the first line pressure P
I! I decreases as gear ratio T EE, /J>,
The line pressure pI is between the gear ratio pressures! Gear ratio lower 1 equal to t
(This gear ratio T1 is the throttle pressure r'th.

Therefore, it is a function of the engine torque Te. ), in the gear ratio range below that, pH = pH. In addition, in FIGS. 8 and 9, the two-dot chain line indicates the first line pressure P.
I! The ideal value of I is TI>72.

The cut-off valve 190 has a chamber 19 that communicates with a control chamber 102 of the lock-up control valve 96 via an oil passage 192.
4, and the hydraulic pressure of chamber +94 and the spring 1 are raised, and the solenoid valve 10
0 is off, that is, when the lock-up clutch 22 is in the released state (when changing gears in the sub-transmission 42, the lock-up clutch 22 is released in order to absorb the shock of the power transmission system). ), the primary regulator valve 1 is in the closed state and the gear ratio pressure is
98.

The primary regulator valve 198 as a first line pressure generating means includes a boat 2001 supplied with throttle pressure Pth, a boat 202 supplied with gear ratio pressure, a boat 204 connected to the line pressure oil path 74, and an oil pump. 26 and the first line pressure Pj? through an orifice 208. 1
a boat 210 that is supplied with a boat 210, a spool 212 that moves axially to control the connection between boats 204 and 206, and a spool 21 that biases the spool 212 toward the boat 202 in response to throttle pressure pth.
4, and a spring 216 that urges the spuffle 212 toward the boat 202. 2 from the bottom of spool 212
[m product of two lands is AI, A2, throttle pressure Pt
When the area of the land of the spool 214 that receives h is defined as A3, and the acting force of the spring 216 is defined as Wl, the following equation holds true.

If the cut-off valve 190 is open and the gear ratio pressure light is on the boat 202, then Pj! 1==(A3・Pth −1−Wl −AI−P
7) / (A2-At)... (l When the cut-off valve 190fJi is closed and the gear ratio pressure is not applied to the boat 202, P/!1-=(A3・Pth+W111/(A2-
AI)... (2) Pjl? defined by equations (1) and (2)? 1 is shown by a solid line and a dash-dotted line in FIGS. 8 and 9, respectively.

The sub-primary regulator valve 220 as a second line pressure generating means generates the first line pressure PI! in the L and D ranges. 1 from the boat 85 of the manual valve 80, an output port 224 where the twelfth line pressure PA2 is generated, a boat 226 where the gear ratio pressure is guided, and a second line pressure P as feedback pressure.
j? 2 through orifice 228
0, a spool 232 that controls the connection between the input boat 222 and the output port 224, a boat 234 that receives throttle pressure pth, and a throttle pressure pth from the boat 234.
the spool 236 and the spool 232 that urge the spool 232 toward the boat 226.
It has a spring 238 biasing towards 6.

The area of the two lands from the bottom of the spool 232 is B1, B
2. If the area of the land of the spool 236 that receives the throttle pressure Pth is defined as B3, and the acting force of the spring 238 is defined as W2, the following equation holds true.

PJ2: (B3・Pth + W2− Bl−Pr
) / (B2-Bl)...(3) Figure 1O shows the second line pressure Pj? generated by the sub-primary regulator valve 220. 2 and its ideal value.

The shift valve 250 has an input port 252 and an output port 254 to which the second line pressure P12 is introduced when in the P and L ranges.
, 256, a boat 262 connected to a discharge oil passage 261 having an orifice 258 and ending at a drain 260, a control port 264 supplied with the first line pressure e71 from the boat 87 of the manual valve 80 in the D range, Other control boats 266.268, drain 2
70, a spool 272, and a spring 274 that biases the spool 272 toward the boat 268. The control boat 266 , 268 is guided through an orifice 276 with a secondary hydraulic pressure Pz, and the hydraulic pressure in the control port 266 , 268 is controlled by a solenoid valve 278 . The areas of the two bottom lands of the spool 272 are Sl and B2, and Sl<52.

Further, whether the solenoid valve 278 is turned on or off is controlled in relation to the driving parameters of the vehicle, and when the solenoid valve 278 is turned on, oil is discharged from the drain 280.

When the spool 272 is in the spring 274 side, the input port 252 is connected to the output port 254 and the output port 256 is connected to the boat 262 ffl! be done. Therefore, the second line pressure P12 is supplied from the output port 254 to the accumulator 282 having the piston 281 and the high-speed clutch 56, and the sub-shift 8!42 is set to the high speed.

When spool 272 is in the port 268 position, input port 252 is connected to output port 256 and output port 254 is connected to drain 270.

Therefore, the second line pressure PJ from the output boat 256
2 is supplied to the low speed accumulator 58, and the auxiliary transmission 42 becomes the low speed.

In the case of a microwave oven, the first line pressure Fll is not introduced to the split boat 264, so when the solenoid valve 278 is turned off, the spuffle 272 is initially activated by the secondary hydraulic pressure Pz acting on the land of the surface FiS2. Thereafter, the land moves toward the spring 274 due to the secondary hydraulic pressure Pz acting on the land with the area Sl, but when the solenoid valve 278 is turned on, the control port 266.
As the oil pressure at 268 decreases, the spool 272
74 towards port 268. That is, in the L range 1, the auxiliary transmission 42 can be switched between a high speed gear and a low speed gear by turning the solenoid valve 278 on and off.

In the D range, the first line pressure PA1 is applied to the control boat 264.
Since fJi is guided, the spool 272 is connected to the -tan spring 27.
When the position is on the 4 side, the control boat 2 is placed on the land with area S2.
The first line pressure PJI from 64 is applied, and regardless of whether the solenoid valve 278 is turned on or off thereafter, the spool 272 is held in the position on the spring 2711 side, and therefore the auxiliary transmission 42 is held in the high speed gear.

The shift timing valve 290 is connected to the high speed clutch 5.
6)-292, and control port 2
What is the spool 294 whose position in the f[h line direction is controlled by the oil pressure of 92, and the flow rate of oil supplied to the high speed clutch 56 and the speed setting brake 58 when upshifting from a low speed to a high speed? Controls the flow rate of oil discharge from.

The solenoid valves 100, 114, 116, 278 receive the secondary hydraulic pressure Pz from the secondary hydraulic oil passage 82, and control the discharge of the secondary hydraulic pressure Pz. In the hydraulic control device disclosed in Japanese Patent Application No. 59-12071, the solenoid valve is guided by the throttle pressure Pth. Therefore, in the Juto device, the spring force and solenoid suction force of the MFDI valve must be set to cope with the maximum throttle pressure, which has the disadvantage of increasing the size of the solenoid valve. There are reports that the responsiveness of the spool of the spool valve deteriorates or that setting the spring force acting on the spool becomes complicated.

In this embodiment, by using the secondary hydraulic pressure Pz, these problems are solved and the degree of freedom in design is improved.

FIG. 11 is a control block diagram. Electronic control device 310
receives parameters such as the intake throttle opening θ, the input side rotational speed Nin of the vehicle speed v1CVTI, the engine cooling water temperature Tw, and the shift position as input signals, and controls the solenoid valves 100.114.116 of the hydraulic control device 312.
, 278 via booster stage 314.

FIG. 12 shows a routine for selecting the control mode of CVT l. First, initialize the electronic control unit 310 (
Step 318), then data necessary for the following control, such as input from various sensors, is read (step 320).

In this way, diagnosis (step 322) is performed to check whether the various R devices are operating normally or not.
Mutual control with the engine computer (step 324), which controls the timing and fuel injection amount, etc., and lock-up control (step 326), which controls engagement and release of the lock-up clutch 22, are executed. The transmission section control includes shift control of CVT I (step 330) and switching of the sub-shift 8!42 between high speed and low speed (step 332). Finally, the control values calculated as a result of these controls are output (step 334). The present invention relates to the shift control of the CVT 1 in step 330.

FIG. 13 shows the relationship between the target input side rotational speed Nino and the shift control of the CVT 1. That is, the target input side rotational speed Nino is compared with the actual input side rotational speed Nin, and Nino≧Nin+ΔNl+Nln+ΔN2≦Ni
no < Nin+ΔN1+Nin < Nino <
Nin+ΔN2. Nin−ΔN3<Nino
<Nin+Nin-ΔN4 <Nino≦Nin
-ΔN3. and Nino≦Nin−ΔN4 (However, ΔN + +ΔN2.ΔN3.ΔN4 is a positive predetermined value)
A rapid downshift, a medium-speed downshift, a slow downshift, a slow upshift, a medium-speed upshift, and a rapid upshift are performed in each case. It will be done.

Figure 14 shows the case divided in Figure 13 and the first and second divisions.
The relationship between the control signals of the solenoid valves 114 and 116 is shown. If Nin0≦Nino, the first gLFa valve■
4 valves are set to 4, that is, the boat 124 of the first spool valve 11O is connected to the drain 126, oil is discharged from the input hydraulic cylinder of the CVT 1 through the drain 126, and a downshift occurs.
In the case of , the first solenoid valve +14 is turned off, i.e. the boat 119 of the first spool valve 110 is
Connected to F. 7.1 degrees. . Air 19 months old 7. An upshift will occur. Ni
In the case of non-Nin+ΔN1, the second solenoid valve + 1'6
is turned off and the boat 1 is turned off at the second spool valve ■2.
34 is connected to boat +36, thereby CVT I
As the cross-sectional area of the oil passage for discharging oil from the input hydraulic cylinder increases, a rapid downshift occurs. Nine
If < Nino < Nin + ΔN2, the second electric 6I! Resident +16 is turned on, boats 134 and 136
As a result, the cross-sectional area of the oil discharge path for oil from the input side hydraulic cylinder of the CVT I becomes zero, and a slow downshift occurs due only to oil leakage from the cylinder or valve.

In the case of Nin+ΔN2≦Nino <Nin+Δ, the second solenoid valve +16 is duty-controlled (controlled by a pulse signal), and the flow passage cross-sectional area of the discharge oil passage changes between the increased state and O at the duty-control frequency. The repetitions result in intermediate magnitudes and downshifts of speed intermediate between rapid and slow downshifts. If Nin-ΔN3 < Nino < Nio, the second solenoid valve 1116 is turned off and the second
Boat +22 and boat 132 at spool valve ■2
The cross-sectional area of the oil supply path for supplying oil to the input hydraulic cylinder of the CVT I is very small, resulting in slow upshifts. Nin0
If ≦N1n-bNd, the second MIJri! i valve port 6
is turned on, and boats +22 and boats +32 are connected at the second spool valve 112, which causes the CVT
The cross-sectional area of the oil supply path for supplying oil to the input hydraulic cylinder 1 is large, and a rapid upshift occurs. ,Ni
In the case of n-ΔN4 < Nino < Nin-ΔN3, the second electromagnetic valve 116 is duty-controlled, and the cross-sectional area of the supply oil passage is in the increased state and in the very small X I?
Repeating between Jl and Jl at the duty-controlled frequency results in an intermediate magnitude change and an intermediate speed upshift between a fast upshift and a slow upshift.

In the present invention, ΔNl to ΔN4 are functions of the intake throttle opening degree θ.

FIG. 15 is a flowchart of the CVT l shift control routine. Step 33: Determine the target input side rotational speed Nino carefully from the intake throttle opening degree 0 and the vehicle speed V.
8) Difference Nin between the target input side rotational speed Nino and the actual input side rotational speed Nio.

-Nio is substituted into 8Nin (step 34θ).

Compare ΔN with 0 (Step 342), ΔNin≧0
, that is, when downshifting is required, the predetermined value Δ
N+, 8N2 is calculated from the intake throttle opening θ (step 344), and when ΔNin<0, that is, when an upshift is required, a predetermined value ΔN3+ΔN4 is calculated from the intake throttle opening θ (step 345). Next, ΔNin and the predetermined value ΔN Sumire, ΔN2, -4 N4, -A
Compare with N3 step 346°347.348,
350), and controls the first and second solenoid valve ports 4, 116 as shown in the case classification of FIG.
steps 352-362).

FIGS. 16 to 18 show changes in the one-town rolling speed Nin on the input side. In Figures 16 and 17, Δ
Nl - ΔNla, ΔN1 = ΔNlb in FIGS. 18 and 19, and ΔN[a < ΔNlb. In Fig. 16 and Fig. 18, the intake throttle opening is 0.
=θa, e=θb in FIGS. 17 and 19, and θa<θb. If Nin≦Nino−ΔN1, a rapid downshift occurs, and Nln > N
When the speed reaches 1n0-ΔN1, an intermediate speed downshift is performed. In this switching, there is a response delay T, within which the rapid downshift continues, and after the response delay T, an intermediate speed downshift begins.

This response delay T is constant regardless of the intake throttle θ, and the shift width of the CVT l during the response delay T is constant, so the amount of change in the input side rotational speed Nin during the response delay T is The larger the input side rotational speed Nin and the target input side rotational speed Ni
The larger the number, the larger the value. ΔNla, ΔNlb
are values set to match θ=θa and θab, respectively, so in the cases of FIGS. 16 and 19, the amount of increase in Nin within the response delay T is appropriate, and Nin is
Approach ino smoothly. On the other hand, Figure 17: Oh! and ΔN I a +ΔNlb are too small and too large, respectively, in the case of FIG. 17 and FIG. 18, and an overshoot of Nin occurs in FIG.

Delay in approaching. In the present invention, since ΔN1 and the like are set as a function of the intake throttle opening degree θ, good control as in the cases of FIGS. 16 and 19 can be obtained.

FIG. 1 is a functional block diagram of the present invention.

Input side rotational speed sensor 363 and throttle opening sensor 364 detect input side rotational speed Nln and intake throttle θ, respectively. Target input side rotation speed calculation means 3
65 calculates the target input side rotation speed Nino based on the intake throttle opening θ, etc., and the difference calculation means 366 calculates the target input side rotation speed Nino based on the intake throttle opening degree θ etc.
o −Nin is calculated as the difference ΔNin. The predetermined value calculation means 368 calculates the predetermined values ΔNl to ΔN4 from the intake throttle degree θ, and the case calculation means 370 compares the difference Δ with the predetermined values ΔN1 to ΔN4 to determine which case in FIG. +), controlling the first and second solenoid valves 114, 116 in each case. The first solenoid valve 114 is used for shifting (upshift or downshift b)
Control: As an n-speed gear, the second solenoid valve 116 functions as a gear change speed control means.

Although the present invention has been described with reference to embodiments, it will be obvious to those skilled in the art that the present invention is not limited thereto and can be modified and modified in various ways.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram of the present invention, Fig. 2 is a skeleton diagram of a power transmission device with CVT, Fig. 3 is a diagram showing the relationship between the range and the operating state of the frictional engagement device, and Figs. 4 to 6
Figure 7 is a detailed diagram of the hydraulic control system, Figure 7 is a detailed diagram of the gear ratio detection valve, Figures 8 and 9 are graphs showing the characteristics of the first line pressure, and Figure 10 is the graph showing the characteristics of the second line pressure. Graphs showing characteristics, FIG. 11 is a control block diagram, FIG. 12 is a diagram showing a selection routine of the CvT control mode, and FIG. 13 is a diagram showing the relationship between target input side rotational speed and shift speed. Figure 14 is a chart showing the control of the first and second electric fuel valves in each case, Figure 15 is a flowchart of the CVT speed change control routine, and Figures 16 to 19 are the input side rotation speeds in various cases. FIG. l...CVT, 114...first solenoid valve, 11
6... Second solenoid valve, 363... Input side rotational speed sensor, 364... Throttle opening sensor, 365
. . . Target input side rotational speed calculation means, 366 . . . Difference detection means, 368 . . . Predetermined value calculation means, 370 . . . Case detection means. -1・-Ideal value of pH □ pH when Kazoto-off pulp is open 1-1 pH when Kazoto-off valve is closed ------ pγ □ Speed ratio r ---Ideal value of pH Maximum value 1 Minimum value □ Speed ratio r - Gear ratio γ Fig. 16 1 hour Fig. 17 1 hour Fig. 18 1 hour Fig. 19 1 hour t

Claims (1)

[Claims] 1. The gear ratio Y of the continuously variable transmission is controlled by the inflow and outflow of the hydraulic medium in one hydraulic cylinder of the continuously variable transmission, and the actual input side rotational speed Nin of the continuously variable transmission is controlled by the target. The gear ratio Y of the continuously variable transmission is controlled so that the input side rotational speed Nino is achieved, a predetermined value is set for the difference between the target input side rotational speed Nino and the actual input side rotational speed Nin, and the hydraulic pressure in the hydraulic cylinder is In a control device for a continuously variable transmission for a vehicle in which the speed of inflow and outflow of a medium is controlled in relation to a comparison result between the difference and the predetermined value, the predetermined value is set as a function of an intake throttle opening. A control device for a continuously variable transmission for a vehicle. 2. The control device according to claim 1, wherein the hydraulic cylinder is an input hydraulic cylinder. 3 Target input side rotation speed and actual input side rotation speed Nin
The first to fourth predetermined values ΔN1 regarding the difference ΔNin from
or ΔN4, and if ΔNin≧ΔN1, ΔN
When 2≦ΔNin<ΔN1, when 0≦ΔNin<ΔN2, when ΔN3<ΔNin<0, ΔN4<ΔNin
The control device according to claim 2, characterized in that the inflow and outflow speeds of the hydraulic medium in the input hydraulic cylinder are switched depending on the case where ≦ΔN3 and the case where ΔNin≦N4. 4. The inflow and outflow of the hydraulic medium in the input hydraulic cylinder and their speeds are controlled by the control pressure controlled by the first solenoid valve. A first spool valve that switches the discharge of the medium, and a second spool valve that controls the flow path cross-sectional area between the input side hydraulic cylinder and the first spool valve by a control pressure controlled by a second solenoid valve. The control device according to claim 3, characterized in that the control device is controlled by.