JPS61103049A - Controller for continuously variable transmission for vehicle - Google Patents

Abstract

PURPOSE:To improve the drive feeling by controlling the speed change ratio of continuously variable transmission during speed change of sub-speed change section. CONSTITUTION:It is decide whether speed change signal is inputted from sub- speed change section (step 164) and proceeds to following steps only when it is inputted. Then it is decided whether speed change in sub-speed change section is down shift or up shift (step 166) while actual input side rotary speed Min is compared with target input side rotary speed Nino (steps 168, 170) thus to control first and second solenoid valves. In case of (a), for example, two solenoid valves are turned off to feed oil slightly to input side hydraulic cylinder at CVT section through an orifice thus to perform quite slow up shift of CVT section. This condition will continue upto the end of speed change of sub-speed change section (steps 180, 182).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to continuously variable transmission for vehicles (hereinafter referred to as "continuously variable transmission").
It's called CVT J. ) related to control devices.

Japanese Patent Application No. 59-123620 and other patents have been proposed in order to increase the controllable speed change range of conventional technical engine power transmission systems that incorporate CVT in their power transmission paths, thereby improving driveability. Dan T! :The J sub-transmission section is added to the power transmission path so as to be in series with the CVT section.

Tokunej @ No. 59-149569 is a power transmission device that includes a CVT section and an auxiliary transmission section in series in the power transmission path of an engine, and the transmission ratio i' (r = N1n + N0) of the CVT section.
ut: However, N1n+N0ut are the input side and 8 force side rotational speeds of the CVT section, respectively. ) target input (!II and continuous rotation speed N1no (drive)
It is disclosed that the setting is made according to the shift range such as range and L (low) range, but when the CVT section shift and the sub-transmission section shift overlap, how should the opening of both shifts be specified? does not indicate anything. For example, if the CVT section continues to upshift during an upshift of the auxiliary transmission section, or if the CVT section continues to downshift during a downshift of the auxiliary transmission section, the amount of change in the gear ratio of the entire power transmission device increases. However, after the upshift or downshift of the auxiliary transmission section is completed, the amount of change in the gear ratio τ due to the downshift or upshift of the CVT section increases, which is disadvantageous in terms of driving sensation.

Problems to be Solved by the Invention It is an object of the present invention to provide a good driving feeling by performing appropriate shift control of the CVT section when a shift in the sub-transmission section occurs during a shift in the CVT section. An object of the present invention is to provide a control device for a vehicle CVT that can perform the following functions.

In order to achieve this object, the present invention provides a vehicle in which a CVT section is provided in series with a multi-speed auxiliary transmission section having a plurality of forward speeds in an engine power transmission path. In the opening device for a continuously variable transmission, the gear ratio of the CVT part is controlled so that a change in the gear ratio of the entire engine excitation transmission path is suppressed during gear shifting of the sub-transmission part.

ADVANTAGE OF THE INVENTION In this way, during a shift in the auxiliary transmission section, the change in the gear ratio of the entire engine excitation transmission path is reduced as a result of the shift control section of the CVT section. The amount of ratio change is reduced and the driving sensation can be improved.

Preferably, the gear ratio of S Ar and CVT m in which upshifts and downshifts of the auxiliary transmission section occur during upshifts and downshifts of the CVT section is stopped during the shift of the auxiliary transmission section, or the CVT section is shifted up and down. When downshifting and upshifting of the auxiliary transmission section occur during shifting and downshifting, the upshifting and downshifting of the CVT section continue at a predetermined speed change speed during the shifting of the auxiliary transmission section.

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

In the 22nd, cvrM51 has 1'N input sheaves 2a+2b-, and a pair of output sheaves 4a+41)N.
It is also provided with a belt 6 that is hung around the sheep on the input side and the output side and transmits the engine power. One input side sheave 2
A is provided on the input shaft 8 so as to be movable 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 JdlO, and the other output side sheave 4b is provided on the output shaft 10 so as to be movable in the axial direction and fixed in the rotational direction. Opposite surfaces of input side sheave 2a + 2b and output side sheave 4
The facing surfaces of a+4b are formed in a tapered shape that increases the mutual distance toward the outside in the radial direction, and the open cross section of the belt 6 is formed in the shape of an isosceles trapezoid. Output side sheave 4a+4b
The pressing force of the input side sheaves 2a + 2b is controlled to the minimum limit that can avoid fracturing of the belt 6 and ensure power transmission.
The pressing force is the gear ratio r of CVT section 1 (=input, i!II]
8 rotational speed Nin / output shaft 1o rotational speed Nout
) to determine. The fluid coupling 12 includes a pump 16 connected to the crankshaft 14 of the engine, and a turbine 18 rotated by oil from the pump 16 and fixed to an input @S. The lock-up clutch 22 controls the connection between the crankshaft 14 and the input shaft 8, and the damper 2
4 absorbs the shock of the moat when the locking clutch is switched from the disengaged state to the engaged state and engine torque fluctuations. When the vehicle speed or engine rotational speed exceeds a predetermined value, the lock-up clutch 22 is maintained 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 pumps oil to the CVT section 1 via the oil field control device.
Send it to the fluid coupling 12 etc. The counter shaft 28 is connected to the CVT section 1
The two gears 3 are provided parallel to the output NJlO of
0°32. The engine power of the output shaft 10 is transferred from the gear 34 coaxial with the output shaft 10 to the gear 3 on the counter shaft 28.
0.32 to the differential gear 36, and from the differential gear 36 to the left wheel drive wheel via the left and right axle shafts 38 and 40. The sub-transmission section 42 is provided coaxially with respect to the output MIO of the CVT section 1. The sub-transmission section 42 includes a Ravigneau type compound planetary gear unit 43, and this planetary gear unit 43 includes first and second sun gears 44, 46, a first
a first planetary gear 48 meshing with the sun gear 44;
A second planetary gear 50 that meshes with this first planetary gear 48 and second sun gear 46, a ring gear 52 that meshes with this il planetary gear 48, and a first
and a carrier 54 rotatably supporting the second planetary gear 48,50. The second sun gear 46 is a CVTV2O3 power shaft 10 as an input part of the sub-transmission section 42.
The carrier 54 is connected to a shaft 64 integral with the gear 34 .
connected to. The high speed gear clutch 56 controls the connection between the shaft 64 and the first sun gear 44, controls the fixation of the first "t:" gear 44 by the low speed gear brake 58, and controls the fixation of the first "t:" gear 44, and the reverse brake. 60 controls fixing of the ring gear 52.

FIG. 3 shows the operating state of each frictional engagement element of the sub-transmission section 42 and the reduction ratio in each range. ○ means an engaged state, × means a released part, and pl and ρ2 are defined from the following equation.

pl=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. That is, in the low gear of the D range, the first sun gear 44 is fixed by the low gear brake 58, so engine power is transmitted at a reduction ratio of 1+01 to 2, and in the high gear of the L and D ranges, the first sun gear 44 is fixed by the low gear brake 58. is engaged and the planetary gear unit 43 rotates as a unit, thereby transmitting the engine power at the reduction ratio l.In the R range, the ring gear 52 is fixed by the reverse brake 60, so the reduction ratio is 1. -1/1) Engine power is transmitted by the reverse rotation of 2.

FIG. 4 shows a selection routine for controlling the CVT. Initialize the shift control computer (step 70)
. Next, read the elevation value from each tumor sensor (step 72).
), Dia Gutsis (step 74) to check whether the various R units are operating normally, communication with the engine control computer that controls the fuel injection amount and ignition timing (step 76), Lock-up control a for controlling engagement and release of lock-up clutch 22 (step 78)
) and the CVTV2O3 transmission section 42. The speed change control includes speed ratio control of the CVT section 1 (step 82) and switching control between a low speed gear and a high speed gear of the auxiliary transmission section 42 (step 84). Normal D range control and L range side leg (
Step 86), CVT during shifting of the auxiliary transmission section 42
control a (step 88), and an N range that controls the gear ratio r of the CVT section l so that when the N range is set while the vehicle is running, the shift range to the next D range or L range is circular. Control (step 90) is included. The present invention provides CVT control during shifting of the auxiliary transmission section 42 in step 88.
Regarding part 1.

FIGS. 5 to 8 are diagrams for explaining the principle of value measurement of the present invention. At time t1, the sub-transmission section 42 starts shifting,
At time t2, the shift of the sub-shift section 42 ends. The target input side rotation speed N1no when the sub-transmission section 42 is in the +5 gear is lower than the innermost input [11t1 rotation speed N1no when the sub-transmission section 42 is in the low gear, and the target input side rotation speed N1no when the sub-transmission section 42 is in the low gear is lower than the target input side rotation speed N1no as the sub-transmission section 42 shifts. The input side rotational speed N1no changes discontinuously.

The broken line indicates the CVT section l when there is no gear shifting in the sub-transmission section 42.
This is the change in the actual input side rotational speed Ntn when the gear ratio control is turned down. In Figure 5, (a) CVTV2
A downshift of the auxiliary transmission section 42 occurs during the O3 downshift, and (b) in FIG. 6. A downshift of the auxiliary transmission section 42 occurs during the CVTV2 O3 upshift, and (c) in FIG.
An upshift of the auxiliary transmission section 42 occurs during the downshift of the CVTV2O3, and an upshift of the auxiliary transmission section 42 occurs during the upshift of the CVT section 1 (d) in FIG. 8. In the embodiment, in the case of (a) (FIG. 5) and (d) (FIG. 8), the CVTV2O3 upshift and downshift are performed during the shift of the sub-transmission section 42, that is, during the period from time t1 to (time t2). (b) (Figure 6) and (C)
In the case of (Fig. 7), while the sub-transmission section 42 is changing gears, the CVT section l
upshifts and downshifts continue. Fifth
In Figures 6 and 7, the dashed-dotted line represents the change in the input side rotational speed Nin when the CVTV2O3 upshift and downshift are stopped. It shows. In the case of a single-point chain, n j41. At time t2 when the amount of change in the gear ratio of the entire force transmission path increases and the shift of the sub-transmission section 42 is completed, the actual input side rotational speed Nin and the target input side rotational speed Nin.

In contrast, in the embodiment, the change in the gear ratio of the entire force transmission path of the engine l is suppressed, and the difference between The amount of change in the gear ratio r of the CVT section l can be small, and a good sense of luck and control can be obtained. Note that (a) (
Figures 5, l and (d) (CV in the case of Figure 8)
Instead of canceling the TV2O3 upshift and downshift, respectively, CVTV2O3 always performs a gradual downshift and upshift to further reduce the amount of change in the entire R open power transmission path, or CVTV2O3
Instead of completely aborting 3-pshifts and downshifts, very gradual upshifts and downshifts may be performed.

FIG. 1 is a block diagram of the main parts of the present invention.

Gear ratio control a! &ff1tos are the first and second spool valves 110, 112, the first and second solenoid valves 11
4.116. During the period when the first solenoid valve 114 is off, the spool 1 of the first spool valve 110
is pushed towards the spring 118 by the secondary Pz of the chamber 117, and the first line pressure pH of the port 119 is applied to the second spool valve 112 via the port 120 of the first spool valve 110. Sent to port 122, boat 124
The connection between the drain 126 and the drain 126 is cut off. During the period when the first solenoid valve 114 is on, the hydraulic pressure in the chamber 117 is discharged through the drain 128 of the first solenoid valve 114, and the spool of the first spool valve 110 is splashed 118 into the chamber 117.
is pushed toward the boat 120, and the line pressure P/! does not occur and the boat 124 is connected to the drain 126. Further, during the period when the second solenoid valve 116 is off, the spool of the second spool valve 112 is pressed toward the spring 130 by the secondary oil field P2 of the chamber 128, and
2 is severed, and boat 134 is connected to boat 136. Ports 1-132, 134 are connected to the CVTV2O3 power side hydraulic cylinder via oil line 138. During the period when the second solenoid valve 116 is on, the hydraulic pressure in the chamber 128 is discharged from the drain 139 of the second solenoid valve 116, and the spool of the second spool valve 112 is pressed toward the chamber 128 by the spring 130. Boat 122 is port 13
2, and the connection between boat 134 and boat 136 is severed. Port 136 is connected to port 1 via oil passage 142.
It is connected to 24. Orifice 140 directs a small amount of oil from boat 122 to port 132 when second solenoid valve 116 is off. Therefore, during the period when the Kl zWt valve 114 is off and the second solenoid valve 116 is on, the CV
Oil is quickly supplied to the TV2O3 power side hydraulic cylinder, and the gear ratio r decreases. During the period W when the first solenoid valve 114 is off and the second solenoid valve 116 is off, the CVT section l
Oil is supplied to the input side hydraulic cylinder through orifice 1.
40, and the gear ratio Y of the CVT section 1 gradually decreases. When the first solenoid valve 114 is on and the second solenoid valve 116 is on, oil is not supplied to or discharged from the input cylinder of the CVT section l, and the CVT
The V2O3 speed ratio r is held constant. First solenoid valve 11
4 is on and the second solenoid valve 116 is off, the oil in the input cylinder 46 is discharged from the drain 126, so the gear ratio r of the CvT section 1 rapidly increases.

The speed change detection means 150 of the auxiliary transmission section detects upshifts and downshifts of the auxiliary transmission section 42, and the target input side rotational speed calculation means 152 calculates the target input side rotational speed N1no based on the intake throttle opening θ, etc. , the input side rotation speed sensor 154 detects the actual input side rotation speed Nin. When Nil<N1no, CVT section l is downshifted, and when Nin>N1no, CVT section l is downshifted.
An upshift is performed. The case detection means 156 includes the speed change detection means 150 and the target input side rotational speed calculation means 152.
, and based on the input from the input side rotational speed sensor 154.
(C) A downshift of the auxiliary transmission section 42 occurs during an upshift of the CVT section l; or (a) A case where an upshift of the auxiliary transmission section 42 occurs during a downshift of the CVT section l.
It is detected whether an upshift of the auxiliary transmission section 42 occurs during an upshift of the T section 1). The solenoid valve control means 158 controls the first and second solenoid valves 114 and 116 depending on the case detected by the case detection means 156. In the case of (a), the first and second solenoid valves 114,1
16 are both turned off, and a small amount of oil is supplied to the input side hydraulic cylinder of the CVT section 1 through the orifice 140, thereby causing an extremely gradual upshift of the CVT section 1 (this upshift is almost the same as a shift stop). ), and in case (b), the first and second solenoid valves 11
4 and 116 are controlled in the same way as in normal times, that is, in the same way as when the auxiliary transmission section 42 is not shifting, so that the upshift of the CVT section 1 is continued, and in the case of (C), the first and second solenoid valves are controlled. 114 and 116 are controlled in the same way as in normal times to continue the downshift of the CVT section 1, and in the case of (d), both the first and second solenoid valves 114 and 116 are turned on and the CVT sl is shifted extremely slowly. downshift (
This downshift is almost the same as shifting and stopping. ).

FIG. 9 shows details of the CVT control routine during the shift of the auxiliary transmission section 42 in step 88 of FIG. 4. First, sub-transmission section 4
Step 1 to determine whether there is a shift signal input in step 2 or not.
64), proceed to the next step only if there is one. Next, in step 166, it is determined what type of shift the sub-transmission section 42 is to perform, that is, whether it is a downshift or an upshift.
), the actual input side rotational speed Nin and the target input side rotational speed N1no are compared (steps 168 and 170),
Any of the cases (a) to (d) described above is detected. Thus, depending on each case, the first and second solenoid valves 114
．． 116 as described in FIG. 1 (steps 172, 1741, 176, 178). Step 172
The control from 178 to 178 is continued until the sub-transmission section 42 completes the shift (steps 180 and 182).

Although the present invention has been described with reference to embodiments, it will be apparent to those skilled in the art that the present invention is not limited thereto, and includes various modifications, variations, and embodiments.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of the main parts of the present invention, Fig. 2 is a skeleton diagram of the engine power transmission path including the CVT section and the auxiliary transmission section, and Fig. 3 is the operating state of each friction engagement device in each shift range. Figure 4 is a diagram showing the selection routine of CVT control mode, Figures 5 to 8 are diagrams explaining the control principle of the present invention, and Figure 9 is CVT control during shifting of the sub-transmission section. It is a flowchart of a routine. 1... CVT section, 42... Sub-transmission section, 116...
First solenoid valve, 118...Second solenoid valve, 150...
Shift detection means of sub-transmission section, 152...Target input side rotation speed calculation means, 154...Input side rotation speed sensor, 1
56... Case detection means, 158... Solenoid valve control means. '! -:, :', -+f One hour in Figure 6 tl t2 One hour t tl t2 One hour in Figure 8 □ Time t

Claims (1)

[Scope of Claims] 1. In a control device for a continuously variable transmission for a vehicle, in which a continuously variable transmission section is provided in series with a stepped sub-transmission section having multiple forward stages in an engine assist transmission path, the sub-transmission section 1. A control device for a continuously variable transmission for a vehicle, characterized in that the gear ratio of the continuously variable transmission section is controlled so that a change in the gear ratio of the entire engine power transmission path is suppressed during gear shifting. 2. If an upshift or a downshift of the auxiliary transmission section occurs during an upshift or a downshift of the continuously variable transmission section, the gear ratio of the continuously variable transmission section is stopped during the shift of the auxiliary transmission section. , a control device according to claim 1. 3. If a downshift or upshift of the auxiliary transmission section occurs during an upshift or a downshift of the continuously variable transmission section, the upshift or downshift of the continuously variable transmission section is performed at a predetermined shift speed during the shift of the auxiliary transmission section. A control device according to claim 1 or 2, characterized in that the control device continues with .