JPH02271158A - Speed change controller of automatic transmission - Google Patents

Abstract

PURPOSE:To restrain the occurrence of speed change shock by reading data corresponding to the judging results of a throttle opening judging means and a speed change mode means out of a memory mean to control an electromagnetic valve for a variable orifice. CONSTITUTION:A variable orifice operated by an electromagnetic valve 19 to vary the area of an oil path is provided at the upstream side of a speed change-over valve in the hydraulic circuit of an automatic transmission. An electromagnetic valve control means 51 reads data according to the throttle opening judged by a throttle opening judging means 52 and the speed change mode judged by a speed change mode judging means 53 out of a memory means 50 previously storing a period of time from the beginning of turning on a friction brake or friction clutch to the insertion of the variable orifice and a period of time taken for releasing the inserted orifice according to the speed change mode and throttle opening, so that said electromagnetic valve 19 is controlled on the basis of the periods of time and thus a speed change shock feeling in the low throttle opening can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a shift control device for an automatic transmission.

(Prior Art) Conventional automatic transmissions generally use a one-way clutch in the power train to improve the feeling of shifting, or a gear shifting system that controls engagement and disengagement of a friction brake or friction clutch. Modulation valves such as accumulator valves and timing valves were used in the switching valves to control speed changes. In addition, some electronic control systems that have been adopted in recent years use electromagnetic valves to perform speed change control by duty control, but these are still only auxiliary to modulation valves. Therefore, the shift valve has a complicated structure and is expensive to manufacture.

Therefore, in order to solve this problem, the applicant of the present invention proposed a method in which a two-stage piston is used as an actuator and a friction member of a friction brake or a friction clutch ρ is pressed through an elastic member (Japanese Unexamined Patent Publication No. 82 (Refer to Publication No.-13849).

That is, as shown in FIGS. 11 and 12, the rear stage of the four-element two-stage torque converter 61 has three forward speeds and one reverse speed.
A transmission 62, which is a planetary gear transmission, is connected thereto. The transmission 62 includes a planetary gear train consisting of a first planetary gear 64a and a second planetary gear 65a that share one planetary carrier 63, a clutch F3 as a friction clutch and a brake as a friction brake that control the planetary gear train. Fl, F2. It has R.

The torque converter 61 consists of a pump 67, a turbine 68, a fixed stator 69, a reversing stator 70, and a lock-up clutch 71.
The structure is such that engine power is transmitted to the

A piston 71a is slidably provided between the lock-up clutch 71 and the front cover 72, and when the piston 71a slides in the direction of the lock-up clutch 71 by hydraulic pressure, both sides of the lock-up clutch 71 are applied with torque. It is a so-called pressurized piston type that serves as a transmission surface.

The turbine 68 is connected to a turbine shaft 68a, and the reversing stator 70 is connected to a stator shaft 70a. The fixed stator 69 is fixed to the housing 62a by a shaft 69a,
The pump 67 is connected to a pump shaft 67a. A ring gear 67b is provided at the transmission side end of the pump shaft 67a.

The ring gear 67b meshes with a gear 74b of an intermediate shaft 74a disposed at the upper part of the housing 62a, and the gear 74b also engages with a PTO (Power Take Off).
) is meshed with the gear 74d of the shaft 74c. A charging pump 75, which is a hydraulic pressure generation source, is provided at the lower part of the housing 62a, and the charging pump 75 is slid by a sliding gear 75a that meshes with a ring gear 67b.

A clutch disk 76a of a third clutch F3 is fixed in the middle of the turbine shaft 68a. clutch F
The third clutch cover 76b is connected to the stator shaft 70a. A second brake F2 is arranged outside the clutch cover 76b, and the brake F2 is fixed to the housing 62a.

A second sun gear 65b is fixed to the end of the stator shaft 70a, and a first sun gear 64b is fixed to the end of the turbine shaft 68a. The first sun gear 64b meshes with the first planet gear 64a, and the second sun gear 65b meshes with the second planet gear 65a.

A first ring gear 64c is provided outside the first planetary gear 64a, and the first ring gear 64c meshes with the first planetary gear 64a. A first brake F1 fixed to the housing 62a is disposed further outside the first ring gear 64c.

A second ring gear 65c meshes with the outer side of the second planetary gear 65a, and a reverse brake R is arranged further outward of the second ring gear 65c.

Brake R is fixed to housing 62a.

As shown in FIG. 12, the first planetary gear 64a and the second planetary gear 65a are held on a planetary carrier 63 in a rotatably engaged state. An output shaft 77 is connected to the planet carrier 63.

The transmission 62 is shifted to first gear by engaging brake F1, shifted to second gear by engaging brake F2, shifted to third gear by engaging clutch F3, and shifted to third gear by engaging brake F2. By engaging the , the gear is shifted to reverse. That is, only brake F1 is engaged, and the other brakes F2. When shifting to 1st speed with R and clutch F3 released, the first ring gear 64c
Power from the engine is inputted from the pump 67 through fluid to the turbine 68, from the turbine shaft 68a to the first sun gear 64b, and through the first planetary gear 64a to the first ring gear 64c. At the same time, it is output to the carrier 63 as a reaction force due to being fixed, and at the same time, it is output to the turbine 68 via fluid from the pump 67.
The reversing force input from the stator shaft 70a to the reversing stator 70 and from the stator shaft 70a to the second sun gear 65b is similarly converted in direction to the carrier 63 via the second planetary gear 65a1 and the first a star gear 64a, and is decelerated and output. be done.

When shifting to second gear, only brake F2 is engaged and other brakes F1, R and clutch F3 are released.
Since only the clutch cover 76b is connected to the housing 62a and the stator shaft 70a stops rotating in reverse, the power from the torque converter 61 is input from the turbine shaft 68a to the first sun gear 64b, and the power is input to the first planetary gear 64a and the second planetary gear. It is decelerated and output to the carrier 63 as a reaction force due to the second sun gear 65b being fixed via the second sun gear 65a.

Only clutch F3 is engaged, and brakes F1, F2. R
During the third speed shift when the stator shaft 70a and the turbine shaft 68a are released, the stator shaft 70a and the turbine shaft 68a rotate together, so the sun gears 65b and 64b of the transmission 62 connected to these shafts 70a and 68a also rotate integrally, and the planetary The entire gear train rotates as one unit, and the reduction ratio i is set to 1.

Only brake R is engaged, and the other brake Fl is engaged.

When F2 and clutch F3 are released, the second ring gear 65c is fixed to the housing 62a, and the engine power is input from the pump 67 to the turbine 68 via fluid, and from the turbine shaft 68a to the first sun gear 64b. The rotational direction is changed as a reaction force from the fact that the second ring gear 65C is fixed via the planetary gear 64a1 and the second planetary gear 65a, and is output to the carrier 63, and at the same time, it is output from the turbine 68 via fluid from the pump 67. The reversing force manually applied to the reversing stator 70 and from the stator shaft 70a to the second sun gear 65b is similarly decelerated and output to the carrier 63 via the second planetary gear 65a.

Clutch F3 and brake Fl, F2. R has a configuration as shown in FIG. That is, a two-stage piston 79 serving as an actuator for the brake F1 is provided at the rear end, that is, the right end, of the housing 62a so as to be slidable in the axial direction. The second stage piston 79 has a substantially annular shape, and has a first stage pressure receiving surface 80 and a second stage pressure receiving surface 81 that are concentric with each other on the right end surface in the figure, and a suppressing part 82 on the left end surface in the figure. It is installed protrudingly. The two-stage piston 79 is slidably fitted into the cylinder wall 83a of the housing 62a.
A compression coil spring 85 supported by a retainer 84 is interposed between and the second stage piston 79, and this spring 85 urges the second stage piston 79 to the right in the figure.

A pressure oil flow port 86 is opened in the first stage pressure receiving surface 80 of the second stage piston 79 . The flow port 86 communicates with a first shift valve (not shown) via a passage 87, and the supply of pressure oil to the passage 87 is controlled by the operation of the first shift valve.

A passage 88 is formed in a portion of the first stage pressure receiving surface 80, and this passage 88 communicates with the second stage pressure receiving surface 81 via an orifice 89 set to a predetermined throttling ratio. The area ratio of the first-stage pressure-receiving surface 80 and the second-stage pressure-receiving surface 81 is approximately 1:2, and the area of the second-stage pressure-receiving surface 81 is set to be larger.

A disc spring 91 as an elastic member is provided between the second stage piston 79 and the brake F1. The disc spring 91 is installed between the outer disc 92 of the brake F1 and the suppressing part 82,
In the illustrated open portion, they are arranged at a predetermined distance d. The spring constant of the disc spring 91 is set to be significantly larger than that of the spring 85, and the maximum spring force of the disc spring 91 is greater than the hydraulic pressure, that is, the pressing force generated only on the first stage pressure receiving surface 80 of the second stage piston 79. is also set large. Therefore, when the hydraulic pressure is acting only on the first stage pressure receiving surface 80, the pressure force of the second stage piston 79 causes the disc spring 9 to
1 is not fully compressed, and the disc spring 91 is interposed between the second-stage piston 79 and the brake F1 in an elastic state.

The brake F1 consists of an outer disc 92, an inner disc 93, a facing 94, etc., and the outer disc 92 is attached to the spline 5i183b of the housing 62a.
It has spline external teeth 95 that are slidably spline-fitted in the axial direction. In addition, the inner disk 93 is the first
The ring gear 64c has spline internal teeth 97 that are slidably spline-fitted in the axial direction to spline external teeth 96 formed on the outer peripheral surface of the ring gear 64c.

Facings 94 are attached to both sides of the inner disk 93, and both disks 92, 93 are arranged opposite to each other alternately. Therefore, the brake F1 is a disc spring 9
Both discs 92 and 93 are configured to be able to be engaged or released by hydraulic pressure, that is, suppressing force, from the two-stage piston 79 transmitted through the piston 1.

A retainer 98 is provided on the left end surface of the brake F1 in the drawing, and the retainer 98 is fixed to the housing 62a to support the pressing force from the two-stage piston 79.

Also clutch F3, brake F2. Since R also has almost the same structure as brake F1, parts that are the same as or correspond to brake F1 are given subscripts T (indicates clutch F3), S (indicates brake F2), and R (indicates brake R), respectively. Illustrated with the addition of

A second-stage piston 79R for the brake R and a second-stage piston 79S for the brake F2 are housed in a substantially annular cylinder 100 so that the second-stage pressure receiving surfaces 8]R and 81S face each other. In addition, the first-stage pressure receiving surfaces 80R and 80S are connected to the manual valve, the briny regulator valve, the 2nd shift valve, and Pressure oil is supplied through passages 101 and 102.

Further, the clutch F3 is pressed by a three-stage piston 103 as an actuator, and is designed to ensure a wide pressure receiving surface within the narrow latch cover 76b and generate a predetermined pressing force. Pressure oil is supplied via passage 104.

For example, when shifting up from the first gear to the second gear, the brake F2 is engaged at a predetermined timing while the brake F1, which is in the engaged state, is released.

During this upshift, pressure oil is supplied to the passage 102 of the brake F2, and is discharged from the passage 87 of the brake F1. Due to the above switching operation, the oil pressure supplied to the first stage pressure receiving surface 80S of the second stage piston 79S rises. Passage 1
When pressure oil is supplied from 02 to the first stage pressure receiving surface 80S at a pressure that overcomes the spring force of the spring 85S, the second stage piston 7
9S slides within a stroke range of interval ds. In this stroke range, the brake F2 remains in the released state.

On the other hand, the oil pressure being supplied to the second stage piston 79 drops rapidly, and the pressure oil being supplied to the passage 87 of the second stage piston 79 is drained. Due to the above draining operation, the pressing load of the brake F1 is rapidly reduced, and from the time of the maximum spring force of the spring 91, the return speed of the second stage piston 79 becomes gentle due to the throttling action of the orifice 89, and eventually reaches zero. . Further, the brake F2 begins to receive the pressing load from the second stage piston 79S via the disc spring 91S. In this state, the pressure oil supplied from the flow port 86S flows only into the first stage pressure receiving surface 80S due to the throttling action of the orifice 89S, and the pressing load on the brake F2 increases relatively slowly. When the hydraulic pressure acting on the first stage pressure receiving surface 80S reaches a predetermined value, pressure oil starts flowing from the orifice 89S to the second stage pressure receiving surface 81S. After this, for a predetermined period, pressure oil only flows into the second stage pressure receiving surface 80S, and the second stage piston 79S
does not stroke, and the pressing load on brake F2 maintains a constant value. Within this period, the torque transmission value of the brake F1 and the torque transmission value of the brake F2 become equal, and after that, the engine torque transmitted to the brake F2 gradually increases, and the share of the brake F1 in torque transmission decreases. Finally, the disc spring 91S is fully compressed and the brake F2 is completely engaged or fixed.

(The problem that the invention seeks to solve M!J) However, in such an automatic transmission, as shown in Fig. 14(a), the pressure increase pattern of the hydraulic pressure acting on the pistons 79, 79S and 103 is independent of the throttle opening. Since it is constant, as the throttle opening becomes smaller as shown in FIGS. 14(b) to 14(d), the peak of the output torque becomes steeper, and the shock feeling of shifting increases. In FIG. 14(a), the solid line a indicates the hydraulic pressure acting on the pistons 79, 79S or 103 of the brakes Fl, F2 or the clutch F3 that are engaged, and the line 1b indicates the brakes F1, F2, . R
Alternatively, it shows the oil pressure acting on the piston 79, 79S or 103 of the clutch F3. Also, Fig. 14 (b
) to (d) are brake Fl, F2 or clutch F3
shows the output torque of the automatic transmission when the throttle opening is engaged, (b) is when the throttle opening is high, (C) is when the throttle opening is medium, and (d) is when the throttle opening is is the case of low opening.

(Means for Solving the Problems) In order to solve the above problems, a shift control device for an automatic transmission according to the present invention includes a plurality of friction brakes or a plurality of friction clutches in a downstream stage of a torque converter that transmits engine power using fluid. It has a planetary gear transmission that switches gears of a plurality of planetary gear elements by appropriately engaging or disengaging a hydraulic actuator, and a hydraulic circuit for driving the actuator is operated by a solenoid valve. In the automatic transmission, the automatic transmission has a transmission switching valve that switches the supply and discharge state of pressure oil to each actuator, and has a structure that supplies pressure oil to the actuator from the start to the end of engagement of the friction brake or friction clutch. A variable orifice is provided upstream of the speed change switching valve in the hydraulic circuit, and is operated by a solenoid valve to switch between inserting the orifice into the oil passage and not inserting the orifice into the oil passage, and controlling means for controlling each of the solenoid valves. , the time from the start of engagement of the friction brake or the friction clutch until the orifice is inserted into the oil passage by the variable orifice and the time until the insertion of the orifice is released are stored in advance according to the speed change mode and the throttle opening. a storage means for determining the throttle opening, a throttle opening determining means for determining the throttle opening, a shifting mode determining means for determining the shifting mode, and data corresponding to the determination results of the throttle opening determining means and the shifting mode determining means. 6) variable orifice solenoid valve control means for reading out the variable orifice solenoid valve from the storage means and controlling the variable orifice solenoid valve based on the reading.

(Function) The solenoid valve for the variable orifice is controlled by the control means,
An orifice is inserted into an oil path for pressure oil to the friction brake or friction clutch, and the engagement time of the friction brake or friction clutch during gear shifting is controlled according to the throttle opening.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 6. The mechanical configuration of the automatic transmission is shown in Figures 11 to 1.
Since it is similar to the conventional device shown in FIG. 3, the drawings are shared.

FIG. 1 is a configuration diagram of a hydraulic circuit of a shift control device for an automatic transmission in an embodiment of the present invention, in which a charging pump 75
The discharge port of is connected to the boat 2a of the manual valve 2 via the passage 1, and the boat 2b of the manual valve 2 is connected to the boat 2b of the manual valve 2.
communicates with the passage 101 of the brake R via the passage 3. A passage 4 branched from the passage 3 communicates with a boat 5a of a briny regulator valve 5, and a boat 2c of the manual valve 2 communicates with boats 7a and 7b of a variable orifice 7 via a passage 6. Solenoid valves 9 and 19 are installed in the passage 6 via orifices. The variable orifice 7 has an orifice 10 which communicates with the bow) 7b. The boat 2d of the manual valve 2 communicates via a passage 12 with the boat 13a of the 2nd shift valve 13, which serves as a shift switching valve, and the boat 2e of the manual valve 2 communicates with the 1st shift valve, which serves as a shift switching valve, via a passage 14. It communicates with the boat 15a of the shift valve 15. 11 change orifice 7 bow)
7c communicates with the boat 15b of the 1st shift valve 15 via a passage 16, and the boat 15b of the 1st shift valve 5 communicates with the 2nd shift valve 13 via a passage 17.
It communicates with the boat 13e. The boat 7d of the variable orifice 7 communicates with the passage 6 via a passage 18, and a solenoid valve 19 is interposed in the passage 18. The boat 13b of the 2nd shift valve 13 communicates with the passage 102 of the brake F2 via the passage 20, and the boat 13c of the 2nd shift valve 13 communicates with the passage 104 of the clutch F3 via the passage 21. The boat 13d of the second shift valve 13 communicates with a passage 24 branched from the passage 1 via a passage 23, and a solenoid valve 25 is interposed in the passage 23. The boat 15c of the 1st shift valve 15 communicates with the passage 87 of the brake F1 via the passage 27, and the passage 28 branched from the passage 27 communicates with the boat 5b of the primary regulator valve 5. 1st
The boat 15d of the shift valve 15 communicates with the passage 24 via a passage 29, and a solenoid valve 30 is interposed in the passage 29.

The boat 5C of the briny regulator valve 5 communicates with the passage 24 via a passage 31, and a solenoid valve 32 is interposed in the passage 31. Solenoid valves 32, 25, and 30 are installed in the passage 24 via orifices. Brimary regulator valve 5 boats 5d, 5e, 5
f communicates with the passage 24, and the boat 5g of the briny regulator valve 5 communicates with the boats 34a, 34b of the secondary regulator valve 34 via the passage 33. The boat 8b of the lock-up valve 8 communicates with the passage 33.
c communicates with the torque converter 61 via the passage 35. The boat 8d of the lock-up valve 8 communicates with the oil chamber of the lock-up clutch 71 in the torque converter 61 via the passage 36, and the boat 34c of the secondary regulator valve 34 communicates with the torque converter 61 via the passage 37. ing. An oil cooler 38 is interposed in the passage 37, and a passage 3 branched from the passage 37
9 communicates with each lubricating section of the automatic transmission. Solenoid valve9.
Solenoids 19, 25, 30, and 32 are electrically connected to the output end of a control circuit 40 as a control means consisting of a microcomputer. As shown in FIG. 2, the control circuit 40 includes a CPU (central processing unit) 42 that processes various data, and a CPU 42 that processes signals from various detectors.
, an output interface 44 that outputs the output signals of the CPU 42 to various control objects, and a memory 45 that is composed of ROM and RAM and stores various data. The CPU 42 receives detection signals via the human power interface 43 from a select position sensor 46 that detects the select position of a select lever (not shown), a vehicle speed sensor 47 that detects vehicle speed, a throttle opening sensor 48 that detects the throttle opening, etc. is manually operated, and the CPU 42 outputs control signals to the solenoids of the electromagnetic valves 9, 19, 25, 30, 32, etc. via the output interface 44.

The control circuit 40 controls the solenoid valves 9, 19, 25, 30, . . . based on a preset program. The automatic transmission is controlled by outputting a control signal to the solenoid F1.32, and one of its functions is to control the solenoid valve 19 as shown in FIG. ．． It has a function of controlling the time of the engagement operation of F2 and clutch F3. That is, the storage means 50 stores the time from the start of engagement of the brakes Fl, F2 or the clutch F3 until the variable orifice 7 inserts the orifice 10 into the oil passage leading from the passage 6 to the passage 16 via the variable orifice 7, and the orifice 10. 10 is stored in advance according to the speed change mode and throttle opening. Note that the shift mode refers to the type of shift, such as shifting from first speed to second speed, or shifting in a lock-up state. The variable orifice solenoid valve control means 51 includes a throttle opening determination means 52 that determines the throttle opening based on the signal from the throttle opening sensor 48, and a throttle opening determination means 52 that determines the throttle opening based on the signal from the select position sensor 46, the state of the solenoid valve 25, 30, etc. According to the result of the judgment with the speed change mode determining means 53 which determines the speed change mode, the optimum data is read from the storage means 50;
Based on this, a control signal is output to the solenoid valve 19. The storage means 50 is realized by the memory 45, and the RIJ variable orifice solenoid valve control means 51, the throttle opening degree judgment means 52, and the speed change mode judgment means 53 are realized by software by the CPU 42.

Next, the operation will be explained. When reverse is selected with the select lever, manual valve 2's boats 2a and 2b
The pressure oil in passage 1 passes through passage 3 to brake R.
passage 101, and the gear is changed to reverse.

Next, when the drive range is selected using the select lever, the boats 2a and 2c of the manual valve 2 communicate with each other, and the pressure oil in the passage 1 is supplied to the passage 6. are in communication, the pressure oil in the passage 6 is supplied to the boat 15b of the 1st shift valve 15 through the passage 16, and is further supplied to the boat 15b of the 1st shift valve 15 through the passage 17.
The water is supplied to the boat 13e of the 2nd shift valve 13 through the 2nd shift valve 13. On the other hand, a control signal is output from the control circuit 4o to the solenoid of the electromagnetic valve 3o, and the pressure oil in the passage 24 is supplied to the boat 15d of the 1st shift valve 15 through the passage 29. As a result, the boat 15 of the 1st shift valve 15
b and the boat 15c communicate with each other, so that the pressure oil in the passage 16 is supplied to the passage 87 of the brake F1 through the passage 27. Therefore, the brake F1 is engaged and the gear is shifted to the first speed. Note that the control signal from the control circuit 4o is stopped from the solenoid valve 32 only when starting with a high throttle opening, and the pressure oil in the boat 5c of the briny regulator valve 5 is drained through the passage 31, and the torque is increased. converter 6
The run-in pressure is set to a high pressure to cope with the increase in the stall torque ratio of 1. During gear shifting, a control signal is always output to the solenoid valve 32, pressure oil from the passage 24 is supplied to the boat 5C of the briny regulator valve 5 via the passage 31, and the run-in pressure is set to high pressure.

For example, if it is assumed that the gear should be shifted to the second speed at time L1 in FIG.
The output of the control signal to the solenoid of the solenoid valve 25 is stopped.
Outputs a control signal to the solenoid. This allows passage 2
4 is supplied to the boat 13d of the 2nd shift valve 13 through the passage 23, so the 2nd shift valve 1
3, the boat 13e and the boat 13b communicate with each other, and the passage 17
Pressure oil is supplied through the passage 20 to the passage 102 of the brake F2. Therefore, the oil pressure supplied to the brake F2 starts to rise as indicated by the solid line C in FIG. 4(a). On the other hand, since the control signal to the solenoid of the solenoid valve 30 is cut off, the pressure oil in the passage 24 is no longer supplied to the boat 15d of the 1st shift valve 15 through the passage 29. 15c communicates with a drain passage, and the pressure oil of the brake F1 is drained through the passage 27. Therefore, the oil pressure of the brake F1 decreases as indicated by the solid line d in FIG. 4(a). and control circuit 40
reads the optimum data according to the speed change mode and the current throttle opening from the memory 45 based on the signal from the throttle opening sensor 48 and the signal from the select position sensor 46, and at time t2 according to the data. A control signal is output to the solenoid of the electromagnetic valve 19, and at time t
3, the output of the control signal to the solenoid of the electromagnetic valve 19 is stopped. In other words, the data read from the memory 45 by the control circuit 40 are at times 81"t2-1l and 52-t3-1.
1. Note that the memory 45 stores the times s1 and 52-sl.
may be stored as data. When a control signal is output to the solenoid of the electromagnetic valve 19 at time t2, the pressure oil in the passage 6 passes through the passage 18 and enters the variable orifice 7.
The variable orifice 7 is supplied to the boat 7d of the variable orifice 7.
b and 7c are connected. Therefore brake F2
The orifice 10 is inserted into the oil passage for the pressure oil, and the supply amount of the pressure oil is restricted, and the rate of increase in the oil pressure decreases as shown by the solid line C. When the output of the control signal to the solenoid of the electromagnetic valve 19 is stopped at time t3, the orifice 10 is removed from the oil passage and returns to its original state, and the engagement of the brake F2 is completely completed at time t4. This is the first
The shift from speed to m2 speed is completed. Note that the engagement of the brake F2 is substantially completed just before time t3. The output torque of the automatic transmission at this time is shown in FIG. 4(b). Note that FIG. 4 shows the case where the throttle opening is high, FIG. 5 shows the case where the throttle opening is medium, and FIG. 6 shows the case where the throttle opening is low. In this way, as the throttle opening becomes lower, the time 5l=t2-
Data is stored in memory 45 such that tl is short.

When the shift to the third speed is reached, the control circuit 40 stops outputting the control signal to the solenoid of the electromagnetic valve 25. As a result, the pressure oil in the passage 24 is no longer co-supplied to the boat 13d of the 2nd shift valve 13 through the passage 23, so the boat 13b of the 2nd shift valve 13 is communicated with the drain passage, and the pressure oil of the brake F2 is At the same time as the drain is drained and the brake F2 is released, the boats 13e and 13c of the 2nd shift valve 13 communicate with each other, and the passage 1
7 pressure oil passes through the passage 21 to the clutch F3 passage]04
supplied to Then, as in the case of shifting from the first gear to the second gear, the $II control circuit 40 controls the solenoid valve 19 based on the data stored in the memory 45, and the gear is shifted to the third gear.

Thus, in the drive range, the control circuit 40 performs speed change control according to the driving state of the vehicle, and when the brakes Fl, F2 and clutch F3 are engaged, time control is performed according to the speed change mode and throttle opening; Similar time control is performed even during downtime.

In this way, since the time sl is shortened as the throttle opening becomes lower, the steepness of the peak of the output torque that occurs when the throttle opening is low can be removed, and the shock You can get an excellent shifting feeling without feeling.

(Another Embodiment) When emphasis is placed on fuel efficiency, it is necessary to lock up the torque converter 61 at all gears, and if the gears are shifted in a locked-up state, even the inertia of the engine itself must be absorbed, and the brake Fl.

Not only does this increase the load on the friction members of F2 and clutch F3, but it also increases the likelihood of shift shock. Therefore, as shown in FIG. 7, the passage 18 may be communicated with the passage 6, and the lock-up solenoid valve 9 may also be used as the solenoid valve for the variable orifice 7.

In the case of a shift in a lock-up state, for example, if the @ control signal is output from the control circuit 40 to the solenoid of the solenoid valve 25 at time tl in FIG. The control signal to is stopped, and the control signal is output again at time t3. That is, the data read from the memory 45 by the control circuit 40 are times 5l=L2-11 and 52-13-tl. This data is of course for lock-up and is based on the throttle opening. During the period from time l to t2, a control signal is output to the solenoid valve 9, so the pressure oil in the passage 6 is supplied to the boat 8a of the lock-up valve 8, and the boat 8a of the lock-up valve 8 is Since the boat 8b and the boat 8d are in communication, the pressure oil in the passage 33 is transferred to the passage 36.
The oil is supplied to the oil chamber of the lock-up clutch 71 through the lock-up clutch 71, and is in a lock-up state.

Also, since the pressure oil in the passage 6 is supplied to the boat 7d of the variable orifice 7 through the passage 18, the boats 7b and 7c of the variable orifice 7 are in communication, and the orifice 10 is inserted into the oil passage. has been done. From time t2 to 13
During this period, the output of the control signal to the solenoid of the electromagnetic valve 9 is stopped, so the orifice 10 is not inserted into the oil path, and the oil pressure of the brake F2 increases rapidly from a predetermined point. . On the other hand, lock-up clutch 7
The oil pressure in oil chamber 1 decreases as shown in FIG. 8(b), and the lockup is released. After time t3, a control signal is output to the solenoid of the solenoid valve 9, so the brake F2
The oil pressure increases slowly. Pressure oil is also supplied to the oil chamber of the lock-up clutch 71, but since there is a free running time of the lock-up piston 71a, lock-up is started at time t4 and completed at time t5.

The engagement of brake F2 is substantially completed just before time t4. The output torque of the automatic transmission at this time is shown in Figure 8 (
Shown in C). In FIG. 8(a), a solid line e indicates the hydraulic pressure of the brake F2 that is engaged, and a solid line f indicates the hydraulic pressure of the brake F1 or clutch F3 that is released.

The operation of the CPU 42 for realizing the above control will be explained with reference to the flowchart shown in FIG. CPU42
If it is determined that a shift is necessary, first read the current gear position from the state of the solenoid valve 30.25 in step a,
Proceed to step b to read the select position from the detection signal of the select position sensor 46, proceed to step C to read the throttle opening from the detection signal of the throttle opening sensor 48, and proceed to step d to read data from the memory 45, that is, regarding the speed change. Read each timer value and step e
The process proceeds to step f, where a control signal is output to the solenoid of the electromagnetic valve 9, and the process proceeds to step f, where it is determined whether or not the shift start timer has timed up.

If the time is up, proceed to step g and close the solenoid valve 25.
Alternatively, a control signal is output to the solenoid of the electromagnetic valve 30. This is time t1 in FIG. Next, the process proceeds to step h, where it is determined whether or not the solenoid valve 9 off timer has timed up. If the time has elapsed, the program proceeds to step i and stops outputting the control signal to the solenoid of the electromagnetic valve 9. This is time t2 in FIG. Next, the process proceeds to step j, where it is determined whether or not the solenoid valve 9 on timer has timed up. If the time has elapsed, the process advances to step k and a control signal is output to the solenoid of the electromagnetic valve 9. This is time t3 in FIG. Next, the process proceeds to step 1, where it is determined whether or not the shift end timer has timed up. If the time has timed up, the routine returns to the normal control routine. Note that if the shift start timer has not timed up in step f, the process proceeds to step h. Further, if the solenoid valve 9 off timer has not timed up in step h, the process proceeds to step j. Also step j
If the solenoid valve 9 on timer has not timed up in step 1, the process proceeds to step 1. Also, if the shift end timer has not timed up in step 1, step m
After waiting for a predetermined time, the process returns to step f.

Note that the shift start timer, solenoid valve 9 off timer, solenoid valve 9 on dimer, and shift path r timer are realized by software by the CPU 42, and the set values of each timer are stored in advance in the memory 45 according to the shift mode and throttle opening. has been done. Therefore, various speed changes in the lock-up region can be handled.

In this embodiment, the lock-up solenoid valve 9 is also used as the solenoid valve for the variable orifice 7, so manufacturing costs can be reduced. In addition, since the lock-up clutch 71 starts to be engaged immediately after the shift is substantially completed, smooth shift is possible. Note that if the lock-up clutch 71 is released at the same time as the shift starts, the engine will rev up before the brakes F1, F2 or clutch F3 on the engagement side begin to engage, since the lock-up region changes to the torque converter region. To prevent this, time t
At time t2 after time s1 from l, lock-up clutch 7
1 is being released. As a result, the brake Fl on the engagement side is applied before the engine starts up.

Since F2 or clutch F3 begins to be engaged, engine revving is suppressed.

Note that for shifting in the torque converter region, similarly to the first embodiment, a control signal is output to the solenoid of the solenoid valve 9 after time sI from the start of the shift, and when time s2 has elapsed from the start of the shift, the control signal is output to the solenoid of the solenoid valve 9. All you have to do is stop the control signal to the solenoid. Even if this is done, it takes time from the output of the control signal to the solenoid of the electromagnetic valve 9 until the lock-up actually starts, so the lock-up will not occur.

Note that the mechanical configuration of the automatic transmission is not limited to that in the above embodiment, and various modifications are possible. For example, as shown in FIG. 10, the piston of clutch F3 may be a two-stage piston 56, and a check ball 57 may be provided inside.

(Effects of the Invention) As explained above, according to the present invention, by controlling the solenoid valve of the variable orifice, the engagement time of the friction brake or friction clutch is controlled according to the throttle opening. It is possible to eliminate the shock feeling that occurs when the opening is low, and it is possible to improve the shift feeling.

Further, by sharing the lock-up solenoid valve as the variable orifice solenoid valve, manufacturing costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a hydraulic circuit of a shift control device for an automatic transmission according to an embodiment of the present invention, FIG. 2 is a block diagram of a control circuit of the shift control device, and FIG. 3 is a control diagram of the shift control device. A functional explanatory diagram of the circuit, FIGS. 4 to 6 are explanatory diagrams of the hydraulic pressure acting on the piston of the friction brake or friction clutch during gear shifting and the output torque of the automatic transmission, and FIG. 7 is an automatic gear shifting in another embodiment. Fig. 8 is an explanatory diagram of the hydraulic pressure acting on the piston of the friction brake or friction clutch and lock-up clutch during gear shifting, and the output torque of the automatic transmission, and Figure 9 is a diagram of the hydraulic circuit of the gear shift control device of the machine. FIG. 10 is a sectional view of essential parts of an automatic transmission in another embodiment, FIG. 11 is a schematic configuration diagram of the automatic transmission, and FIG. 12 is a flowchart showing the operation of the CPU in FIG. 11. -A schematic cross-sectional view taken along line A, Figure 13 is a cross-sectional view of the main parts of an automatic transmission, and Figure 14 shows a piston of a friction brake or friction clutch during gear shifting in an automatic transmission that employs a conventional transmission control device. FIG. 3 is an explanatory diagram of the applied hydraulic pressure and the output torque of the automatic transmission. 7...Variable orifice, 9, 19, 25.30°32
... Solenoid valve, 10... Orifice, 13...2n
d shift valve (switching valve for speed change), 15... 1st shift valve (switching valve for speed change), 40... control circuit (control means), 50... memory means, 51... solenoid for variable orifice Valve control means, 52... Throttle opening judgment means, 53... Speed change mode judgment means, 61... Torque converter, 62... Transmission (planetary gear transmission),
56.79.79R, 79S... 2nd stage piston (actuator), 103... 3rd stage piston (actuator), Fl, F2. R... Brake (friction brake), F3... Clutch (friction clutch) Patent applicant: Daikin Seisakusho Co., Ltd. Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 6 Figure 70 Figure 562 stage Hi0stone Figure 8 Figure 9 Figure 11 Figure 12 Figure 4b

Claims (1)

[Claims] 1. A plurality of friction brakes or friction clutches are appropriately engaged or disengaged by a plurality of hydraulic actuators at the downstream stage of a torque converter that transmits engine power using fluid, thereby controlling a plurality of planetary gear elements. It has a planetary gear transmission that switches gears, and the hydraulic circuit for driving the actuator has a shift switching valve that is operated by a solenoid valve to switch the supply and discharge state of pressure oil to each actuator. In the automatic transmission configured to supply pressure oil to the actuator from the start to the end of engagement of the friction brake or the friction clutch, the hydraulic circuit is operated by a solenoid valve upstream of the shift changeover valve. A variable orifice that can be switched between inserting and not inserting the orifice into the oil passage is provided, and the control means for controlling each of the electromagnetic valves includes a variable orifice that inserts the orifice into the oil passage from the start of engagement of the friction brake or friction clutch. a storage means for pre-memorizing the time until inserting the orifice and the time until releasing the orifice according to the speed change mode and the throttle opening; and a throttle opening determining means for determining the throttle opening; A speed change mode determination means for determining a speed change mode, and data corresponding to the determination results of the throttle opening degree determination means and the speed change mode determination means are read from the storage means and based on the data, the electromagnetic valve for the variable orifice is controlled. 1. A speed change control device for an automatic transmission, comprising a variable orifice solenoid valve control means. 2. The speed change control device for an automatic transmission according to claim 1, wherein a lock-up solenoid valve is commonly used as the solenoid valve for the variable orifice.