JPH10184880A - Controller of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the accuracy in correction of duty drive control relative to the change of the line pressure, and reduce the shock at the gear change, by correcting the duty drive control to a solenoid valve according to the line pressure in a hydraulic controller at the gear change. SOLUTION: The outputs of an oil temperature sensor 4e, an oil pressure sensor 4f, or the like for detecting the oil temperature and the line pressure in a shift select lever switch and an oil pressure controller 3, are read in ECU 4, and a transmission input shaft torque is computed on the basis of an engine rotational speed and the transmission input shaft rotational speed. A target speed is read on the basis of the throttle opening, and the transmission output shaft rotational speed. Further a duty base value to a solenoid valve 400 (400A-400D) is read corresponding to the transmission output shaft torque or the like, and the output duty for driving the solenoid valve 400, is computed by multiplying the duty base value and a correction coefficient together, after the correction coefficient to the duty base value is read from the line pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission that can be shifted by hydraulic operation of a selected friction element.
Correction of duty drive control to the solenoid valve according to the line pressure in the hydraulic control device detected by the pressure sensor installed in the hydraulic control device, thereby improving the shock during shifting caused by changes in the line pressure The present invention relates to a control device for an automatic transmission.

[0002]

2. Description of the Related Art A shift lever switch operated by a driver, an engine shaft rotation speed detection sensor, and an oil temperature sensor are provided. During shifting, oil flow control to a hydraulic piston cylinder is controlled according to various rotation speeds, engine load, and the like. In a conventional automatic transmission that performs hydraulic control and engages and disengages hydraulic friction coefficients, as shown in FIG. 7, the discharge amount of an oil pump in a hydraulic control device changes due to the engine rotation speed, and the line pressure changes. I do. Due to the change in the line pressure, the hydraulic pressure applied to the hydraulic friction element also fluctuates. As shown in FIG. 8, the duty drive control (duty rate) for the solenoid valve required to maintain a certain hydraulic pressure P depends on the engine rotational speed. (NE1, NE2, NE3) causes variations (D1, D2, D3). For this reason, in the conventional device, the duty drive control for the solenoid valve is corrected by the engine rotation speed.

[0003]

However, in the pre-stop shift or the ND / NR shift, since the shift is performed in a region where the engine rotational speed is low in FIG. 7, the line pressure for the shift is sharply increased. It fluctuates unstable. Further, when the driver re-accelerates by depressing the throttle during the shift before stopping, the engine rotation speed increases, so that the discharge amount of the oil pump increases, and the line pressure fluctuates rapidly and unstablely. Therefore, in a shift in a region where the engine rotation speed is low as in the above-mentioned shift, there is a problem that if a correction is made to the duty drive control based on the engine rotation speed, a large error occurs, which leads to a shift shock.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and takes in a line pressure in a hydraulic control device detected by a pressure sensor attached to the hydraulic control device into a control device. An object of the present invention is to improve the accuracy of the correction to the duty drive control for a change in the line pressure by correcting the duty drive control for the solenoid valve in accordance with the line pressure.

[0005]

According to a first aspect of the present invention, there is provided a control device for an automatic transmission, which performs a correction to a duty drive control for a solenoid valve in accordance with a line pressure in a hydraulic control device at the time of shifting. Thus, the accuracy of the correction to the duty drive control for the change in the line pressure is improved, and the shock at the time of shifting is improved.

According to a second aspect of the present invention, there is provided a control apparatus for an automatic transmission, which performs a duty control on a solenoid valve in accordance with a line pressure in a hydraulic control apparatus during an ND shift to thereby correct a line drive. It is intended to improve the accuracy of correction to the duty drive control with respect to a change in pressure, and to improve shock during shifting.

According to a third aspect of the present invention, there is provided a control system for an automatic transmission, which performs a duty cycle control on a solenoid valve in accordance with a line pressure in a hydraulic control system during an NR shift to thereby correct a line drive. It is intended to improve the accuracy of correction to the duty drive control with respect to a change in pressure, and to improve shock during shifting.

According to a fourth aspect of the present invention, there is provided a control apparatus for an automatic transmission, which performs a duty shift control on a solenoid valve in accordance with a line pressure in a hydraulic control unit during a shift before stopping, so that a line pressure is corrected. In this case, the accuracy of the correction to the duty drive control with respect to the change of the speed is improved, and the shock at the time of shifting is improved.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a block diagram showing a schematic configuration of a main part of Embodiment 1 of the present invention. Reference numeral 1 denotes a main body of the engine, in which a pump as an input element of a torque converter 12 connected to a drive shaft 10 directly connected to a crankshaft of the engine 1 rotates internal hydraulic oil, and an output connected to a turbine as an output element. The driving force (torque increased) taken out from the shaft 26 is input to the transmission 2. In the transmission 2, an electro-hydraulic conversion valve (400 A, 400 A) interposed in the hydraulic control device 3 by the electronic control device 4 (hereinafter, referred to as ECU 4) in order to transmit driving force according to the running state of the vehicle to the drive wheels.
B, 400C, and 400D) to switch the operation combination of the hydraulic friction element 2A and the gear device 2B to achieve a desired shift speed, and from the output shaft 62 via the differential gear device 72 and the drive axle 74. To the drive wheels 78. E
The CU 4 has an output signal of a throttle opening sensor 4d for detecting an opening of a throttle valve 1A interposed in an intake pipe (not shown) of the engine 1, an engine rotation speed sensor 4a, and an input shaft rotation speed sensor of the transmission 2. 4b, output shaft rotation speed sensor 4c, oil temperature sensor 4e for detecting control oil temperature in transmission 2, signal for detecting line pressure in hydraulic control device 3 by oil pressure sensor 4f, longitudinal acceleration of vehicle Input, such as an acceleration sensor (not shown), a brake switch (not shown), a shift select lever switch (not shown) signal, etc., to detect the running state of the vehicle, and set the transmission 2 to the detected vehicle running state. Shift control is performed to the corresponding shift speed.

FIG. 2 is a skeletal view showing a gear transmission of an automatic transmission capable of achieving four forward speeds and one reverse speed according to the first embodiment of the present invention.
A drive shaft 10 directly connected to a crankshaft (not shown) is connected to a pump 16 of the torque converter 12 via an input casing 14 of the torque converter 12, and a stator 18 of the torque converter 12 is connected to a one-way clutch 20. Through the transmission casing 22.

The turbine 24 of the torque converter 12
Is an overdrive clutch 28 (hereinafter simply referred to as OD clutch 28) as a third engagement element, and an underdrive clutch 30 (hereinafter simply referred to as UD clutch 30) as a fourth engagement element via the input shaft 26. , And a reverse clutch 32 (hereinafter, simply referred to as an R clutch 32)
It is connected to.

The output shaft of the OD clutch 28 is connected via a first intermediate shaft 34 to a first carrier 38 of a first simple planetary gear set 36 (hereinafter simply referred to as a first gear set 36) and a second carrier 38.
While being connected to the second carrier 42 of the simple planetary gear device 40 (hereinafter simply referred to as the second gear device 40),
The first intermediate shaft 34 is connected to a low reverse brake 44 (hereinafter simply referred to as an L & R brake 44) as a first engagement element for stopping the rotation of the first intermediate shaft 34. The U
The output side of the D clutch 30 is connected to the first
It is connected to a sun gear 46. The output side of the R clutch 32 is connected to the first gear device 36 via a second intermediate shaft 48.
Is connected to the first ring gear 50 and the second sun gear 52 of the second gear train 40, and is connected to a 2-4 brake 54 as a second engagement element for stopping the rotation of the second intermediate shaft 48. Have been.

The first gear unit 36 includes the first sun gear 46, a first pinion gear 56 meshing with the sun gear 46, the first carrier 38 rotatably supporting the pinion gear 56, and being rotatable by itself. First
The first ring gear 5 meshing with the pinion gear 56
0. The second gear device 40 includes the second sun gear 52, a second pinion gear 58 that meshes with the sun gear 52, the second carrier 42 that rotatably supports the pinion gear 58, and that can rotate itself.
The second ring gear 60 is configured to mesh with the second pinion gear 58. The second ring gear 60 is connected to an output gear 64 via a hollow output shaft 62 through which the first intermediate shaft 34 is inserted. The output gear 64 is provided with a non-drive gear 6 provided on the right side of an intermediate transmission shaft 66 disposed substantially parallel to the input shaft 26.
The left end of the intermediate transmission shaft 66 is connected to a final reduction gear 76 connected to a drive axle 74 via a differential gear device 72. As is clear from FIG. 2, the transmission casing 22 extends from the torque converter 12 to the output gear 64.
And an intermediate transmission shaft 66, a differential gear device 72, and the like.

Each of the clutches and brakes has an engagement piston device or a servo device, respectively.
The engagement / release operation is performed by supplying / discharging the hydraulic pressure. The hydraulic pressure is selectively supplied to each of the clutches and brakes by the hydraulic pressure control device 3, and the forward hydraulic pressure is determined by a combination of the operation of each of the clutches and brakes.
A single reverse gear is achieved.

Table 1 shows the operating states of the clutches and brakes at each shift speed. In the same table, "O" indicates engagement of the clutch or brake, and "-" indicates release. Is shown.

[0016]

[Table 1]

In the above-described configuration, when the L & R brake 44 is engaged, the first carrier 38 and the second carrier 42 are fixed to form a reaction force element, and as is apparent from Table 1, there is no power transmission path and neutral is achieved. .

Next, when the UD clutch 30 is engaged while the connected state of the L & R brake 44 is maintained, the driving force from the torque converter 12 is applied to the input shaft 26, the UD clutch 30, the first sun gear 46, the first pinion gear. 56, a first ring gear 50, a second sun gear 52, a second pinion gear 58, and a transmission axle transmitted to an output shaft 62 via a second ring gear 60, and further via an output gear 64, an intermediate transmission shaft 66, and a final reduction gear 76. The first speed is attained as transmitted from FIG.

Next, when the L & R brake 44 is released and the 2-4 brake 54 is engaged while maintaining the engaged state of the UD clutch 30, the rotation of the first ring gear 50 and the second sun gear 52 is stopped. The first sun gear 46, the first carrier 38, and the second carrier 4
2, transmitted to the second ring gear 60 and the output shaft 62,
Speed is achieved.

Next, when the 2-4 brake 54 is released and the OD clutch 28 is engaged while the engaged state of the UD clutch 30 is maintained, the first sun gear 46 and the first carrier 38 are integrally formed. As a result, the entire first gear device 36 rotates integrally, and accordingly, the entire second gear device 40 also rotates integrally, so that the input shaft 26 and the output shaft 62 have the same rotational speed. Speed is achieved.

Next, the UD clutch 30 is released and the 2-4 brake 5
4, the rotation of the second sun gear 52 stops and becomes a reaction force element. Therefore, the driving force is transmitted from the input shaft 26 to the OD clutch 28, the first carrier 38, the first intermediate shaft 34, the second carrier 42, Second pinion gear 58, second ring gear 6
0, which is transmitted to the output shaft 62, and the fourth speed of overdrive in which the rotation of the output shaft 62 is faster than the rotation of the input shaft 26 is achieved.

Next, when the OD clutch 28, the 2-4 brake 54 is released and the L & R brake 44 is engaged, the first carrier 38 and the second carrier 42 are fixed to become a reaction element, and the R clutch 32 is engaged. As a result, the driving force is transmitted to the second intermediate shaft 48, the first ring gear 50, the second sun gear 52, the second pinion gear 58, the second ring gear 60, and the output shaft 62, thereby achieving the reverse gear.

Next, in the gear transmission shown in FIG.
The configuration and operation of the hydraulic control device 3 for achieving each shift speed shown in Table 1 will be described. The hydraulic control device according to the first embodiment of the present invention shown in FIG. 3 includes an oil pump 8 from an oil pan 80 through a filter 82 and an oil passage 84.
6 is supplied to the torque converter 12 and the hydraulic pressure discharged from the oil pump 86 to the oil passage 88 is supplied to the torque converter 12 and the clutches 28, 30, 32,
And selectively supplies and discharges the clutches and brakes to engage and disengage the brakes 44 and 54 in accordance with the driving state of the vehicle. The pressure regulating valve 100, the torque converter control valve 200, and the manual valve 300 , The first electro-hydraulic conversion valve 400A (hereinafter, L & R solenoid valve 400)
A), the second electro-hydraulic conversion valve 400B (hereinafter, referred to as A).
2-4 solenoid valve 400B), third electro-hydraulic conversion valve 400C (hereinafter referred to as UD solenoid valve 4B).
00C), a fourth electro-hydraulic conversion valve 400D (hereinafter, referred to as an OD solenoid valve 400D), and a line pressure switching valve 500, which are connected by an oil passage. The oil pressure sensor 4f is connected to the oil passage 88
And sends a signal to the ECU 4.

The pressure regulating valve 100 adjusts the oil pressure (line pressure) of the oil passage 88 to a desired value corresponding to the shift speed, and includes a land 10 having a pressure receiving surface 102 and a pressure receiving surface 104.
6. Pressure receiving surface 108 and pressure receiving surface 1 facing pressure receiving surface 104
And a land 11 having a pressure receiving surface 114 and a pressure receiving surface 116 opposed to the pressure receiving surface 110.
8. Pressure receiving surface 120 and pressure receiving surface 1 facing pressure receiving surface 116
22, a land 130 having a pressure receiving surface 126 and a pressure receiving surface 128 substantially opposed to the pressure receiving surface 122, and a pressure receiving surface 132 facing the pressure receiving surface 128.
The pressure receiving surface 108 is larger than the pressure receiving surface 104. The spool 138 includes a spool 138 having a land 136 formed thereon, and a spring 140 that abuts on the land 136 and biases the spool 138 rightward in FIG. The pressure receiving surface 114 has a pressure receiving area larger than the pressure receiving surface 110, and the pressure receiving surface 120 has a pressure receiving area larger than the pressure receiving surface 116, and the pressure receiving surface 122, the pressure receiving surface 126, the pressure receiving surface 128, and Each of the pressure receiving surfaces 132 has the same pressure receiving area. Then, the pressure receiving surface 102
An oil passage 144 having an orifice 142 interposed therebetween, an oil passage 88 between the pressure receiving surfaces 104 and 108 via an oil passage 148 having an orifice 146 interposed therebetween, and pressure receiving surfaces 110 and 114.
An oil passage 152 provided with an orifice 150 is interposed therebetween, an oil passage 156 provided with an orifice 154 between the pressure receiving surfaces 116 and 120, and an oil passage 158 provided between the lands 130 and 136. Orifice 16 of oil passage 88 and oil passage 160
The oil passage 164 communicated with the second downstream side is communicated with each other, and the land 130 and the land 124 are communicated with the oil passage 84 via the oil passage 166.

The torque converter control valve 200 includes a land 206 having pressure receiving surfaces 202 and 204, and a land 206 having the same.
A spool valve 214 formed with a land 212 having a pressure-receiving surface 208 having the same pressure-receiving area as the pressure-receiving surface 204, and a spool 21 abutting on the land 212.
4 and a spring 216 for urging the oil passage 88 to the right in FIG. 3. The oil pressure of the oil passage 88 regulated by the pressure regulating valve 100 is applied to the oil passage 160, the oil passage 168, and the orifice 170. The pressure is applied to the pressure receiving surface 202 via the passage 172 to adjust the oil pressure of the oil passage 168 to a predetermined pressure by balance with the urging force of the spring 216, and is supplied to the torque converter 12 via the oil passage 168. The oil discharged from the torque converter 12 is supplied to each lubrication unit of the transmission via an oil passage 174.

The manual valve 300 has a spool 302 in which the positions of R, N, P and D can be selected. The spool 302 sets lands 304, 306, 308 and 310 and sets the spool to a desired position. For this reason, it is arranged in the passenger compartment, and it is possible to change gears between the P position used during normal parking, the R position for reverse movement, the N position for stopping, and the first to fourth forward gears. D4 position, D3 position at which a shift between the first to third speeds is possible, 2 position at which shifting to third or higher speed is prohibited, and second or higher speed And a connecting portion mechanically or electrically connected to a conventionally known shift select lever (not shown) provided with an L position at which shifting to a gear is prohibited. Then, when the shift select lever is operated to select one of D4, D3, 2, and L, the spool 302 is moved to the D position, and communicates with the oil passage 88, the oil passage 314, and each solenoid valve. The oil passage 316 communicates with a space between the land 304 and the land 306, and the oil passage 144 and the oil discharge passage 320 communicating with the discharge port 318 communicate with the land 30.
8 and land 310, oil passage 322, land 3
04 is communicated via a hydraulic chamber 323 on the right side, and as will be described later, an L & R solenoid valve 400A, a 2-4 solenoid valve 400B, a UD solenoid valve 400C, OD
The gear transmission shown in FIG. 2 appropriately achieves the forward gear corresponding to the selected position of the shift select lever and the driving state of the vehicle according to the combination of ON and OFF of the solenoid valve 400D.

When the shift select lever is set to the P or N position, the spool 302 is set to the N or P position shown in the drawing, and the oil passage 88 and the oil passage 144 are located between the oil passage 324 and the land 308 and the land 310. Oil space 8 through the space of
8 and the oil passage 314 are communicated with each other via a space between the land 304 and the land 306, and the oil passage 3 connected to the R clutch 32 with the orifice 326 interposed therebetween.
28 and the oil drain 320 are communicated via the space between the land 306 and the land 308, the oil duct 322, and the hydraulic chamber 323, and the oil duct 316 is also communicated with the oil drain 320 to be in a neutral state. To achieve.

When the shift select lever is set to the R position, the spool 302 is set to the R position, and the oil passage 88, the oil passage 314, and the oil passage 328 are connected to the land 304 and the land 3 respectively.
06 and the oil passage 14
4 and the oil discharge passage 320 communicate with each other through the space between the land 306 and the land 308, the oil passage 322, and the hydraulic chamber 323, and the oil passage 316 also communicates with the oil discharge passage 320, as described later. Then, the gear transmission is caused to attain the reverse shift state (gear position).

The L & R solenoid valve 400A is ECU
A normally open three-way valve that operates in response to a control signal from 4,
A solenoid coil 402a, a valve body 404a, and a spring 406a for urging the valve body 404a in the opening direction are provided therein. When the solenoid coil 402a is in a non-excited state, the valve body 404a is connected to the oil passage 320 and the orifice. 408 is interposed to interrupt communication with the oil passage 410 connected to the L & R brake 44 and
And the oil passage 316 or the oil passage 3 via the check valve 412.
28 is communicated with an oil passage 414 through which the hydraulic pressure of the valve body 4 is guided.
An oil passage 04a is configured to cut off communication between the oil passage 410 and the oil passage 414 and communicate with the oil passage 410 and the oil discharge passage 320.

The solenoid valve 400B is a normally-closed three-way valve having a solenoid coil 402b and a valve body 4 inside.
04b, and a spring 406b for urging the valve body 404b in the closing direction are provided.
In the non-excited state of 2b, the valve body 404b is
6 and the orifice 415 are interposed, the communication between the oil passage 416 connected to the 2-4 brake 54 is cut off, and the oil passage 416 and the oil discharge passage 320 are communicated with each other. The valve element 404b is configured to block communication between the oil passage 320 and the oil passage 416 and to connect the oil passage 416 and the oil passage 316.

UD and OD solenoid valve 400C,
400D is a normally open three-way valve similar to the above L & R solenoid valve 400A, and has a solenoid coil 402 inside.
c, 402d, valve body 404c, 404d, and valve body 404
c, a spring 406c for urging the 404d in the opening direction;
When the solenoid coils 402c and 402d are not excited, the valve bodies 404c and 404d are connected to the oil discharge passage 320 and the orifice 41, respectively.
8, 420 are interposed to interrupt the communication with the oil passages 422, 424 connected to the UD clutch 30 and the OD clutch 28, and at the same time, the oil passages 422, 424 and the oil passage 316 are communicated. In the excited state of 402d, the valve bodies 404c and 404d
0 and the oil passages 422 and 424, and the communication between the oil passages 422 and 424 and the oil passage 316 is shut off.

Each solenoid valve 400A, 400B,
400C, 400D "ON" (excitation), "OFF"
The relationship between the combination of (non-excitation) and the shift speed is as shown in Table 2. "-" In the table indicates that either ON or OFF may be used.

[0033]

[Table 2]

The line pressure switching valve 500 is for switching the line pressure to a value corresponding to the shift speed, and has a pressure receiving surface 504 and a pressure receiving surface 506 on which the oil pressure of the oil passage 314 in which the orifice 502 is interposed acts. A spool valve 518 formed with a land 508 and a land 516 facing the pressure receiving surface 506 and having a pressure receiving surface 510 having the same pressure receiving area as the pressure receiving surface 506 and a pressure receiving surface 514 on which the oil pressure of the oil passage 424 acts. And a spring 520 that abuts against the pressure receiving surface 514 and urges the spool valve 518 rightward in FIG. 3. When the oil pressure is supplied to the oil passage 314 and the oil pressure is not supplied to the oil passage 424. Since the pressure acting on the pressure receiving surface 504 overcomes the urging force of the spring 520 and displaces the spool valve 518 to the left in the drawing, the oil passage 156 And Ex port is the land 508 5
10 and the oil passage 424 and the oil passage 31
4 is not supplied with oil pressure, or when oil pressure is supplied to the oil passage 424, the spring 5
The spool valve 518 is displaced rightward in the drawing by the urging force of 20 or the urging force and the pressure acting on the pressure receiving surface 514, so that the oil passage 156 and the oil passage 424 communicate with each other via the hydraulic chamber on the left side of the land 516. .

Next, the operation of the hydraulic control device 3 will be described. When the driver of the vehicle sets a shift select lever (not shown) disposed in the passenger compartment to the P or N position, the spool 302 of the manual valve 300 mechanically or electrically connected to the shift select lever also shifts to the shift select position. It is set to the PN position in conjunction with the lever. And
When the engine is started, the oil pressure generated by the oil pump 86 is discharged to the oil passage 88, and the oil pressure acts on the pressure receiving surfaces 104 and 108 of the pressure regulating valve 100 via the oil passage 148, and the oil passage 324 and the manual valve 300 between the land 308 and the land 310, the oil pressure passage 144 through the oil passage 144.
0 acts on the pressure receiving surface 102.

The spool 138 of the pressure regulating valve 100 is stabilized at a position where the pressure acting on each of the pressure receiving surfaces and the biasing force of the spring 140 are balanced, and is moved to the space between the lands 130 and 136 via the oil passage 158. A part of the guided oil pressure is discharged to the oil passages 164 and 166, and the oil pressure in the oil passage 88 is adjusted to the lowest predetermined pressure (referred to as a first line pressure).

The hydraulic pressure of the oil passage 88 and the oil passage 164 is
It is guided to the torque converter control valve 200 via the oil passage 160 and supplies a predetermined pressure to the torque converter 12 via the oil passage 168. Further, the oil pressure of the oil passage 88 is controlled by the manual valve 3
The space between the lands 304 and 306 of 00, an oil passage 314
Through the oil pressure line 156 and the oil discharge passage 320 by displacing the spool 518 to the left end position in FIG. 3 by overcoming the urging force of the spring 520 and acting on the pressure receiving surface 504. And the communication state. In addition, each solenoid valve 400A, 400B, 400
C and 400D are all kept in the OFF (non-excited) state.

Here, when the driver operates the shift select lever to select the D4 position, the manual valve 300 is set to the D position, the oil passage 324 is shut off by the land 310, and the oil passage 144 and the oil passage 322 are connected. And the hydraulic pressure in the right end hydraulic chamber of the pressure regulating valve 100 is discharged through the oil passage 322 and the oil discharge passage 320. The oil passage 88 is further provided with an oil passage 316 through a space between the land 304 and the land 306 of the manual valve 300.
The oil pressure in the oil passage 316 is guided to the space between the land 112 and the land 118 of the pressure regulating valve 100 via the oil passage 152. The spool 138 is connected to the pressure receiving surface 11.
0, 114, and the pressure acting on the pressure receiving surfaces 104, 108 and the biasing force of the spring 140 are stabilized at a position where they are balanced.
Then, the oil pressure in the oil passage 88 is adjusted to a relatively high pressure (for example, 10 kgf / cm 2) to a predetermined pressure (referred to as a second line pressure). The oil pressure in the oil passage 316 is guided to the solenoid valves 400B, 400C, and 400D, and is transmitted through the check valve 412 and the oil passage 414 to the L & R.
It is also led to the solenoid valve 400A. Oil passage 3
14 is held in communication with the oil passage 88 as in the case of the N and P positions.

When the shift select lever is set to the D4 position, as shown in Table 1, the L & R brake 44 and the UD clutch 30 are engaged to achieve the first speed, and the ECU 4 transmits the gear. As shown in Table 2, L & R, 2
-4, UD solenoid valve 400A, 400B, 40
0C is kept in the non-excited state, and the OD solenoid valve 40
0D is changed from the non-excited state to the excited state, and only the L & R and UD solenoid valves 400A and 400C are opened to output control signals for communicating the oil passages 414 and 410, and the oil passages 316 and 422, respectively. You.

FIG. 4 shows a schematic configuration inside ECU 4 according to the first embodiment of the present invention, in which output signals from an acceleration sensor (not shown) and the like are converted to level conversion circuit 600 and A / A
D converter 601, waveform shaping circuit 602 and input port 6
In order to control the speed of the automatic transmission 2 to a gear corresponding to the traveling state of the vehicle based on the analog signal, pulse signal, and switch signal obtained from the output signal 03, an output port 604 through the solenoid valve driving circuit 605 The clutch and brake solenoid valves corresponding to the gears are engaged / disengaged by, for example, duty driving to control the shift. Microprocessor (CPU)
The control procedure and data of 606 are stored in the ROM 607 in advance, and the data in the calculation process is temporarily stored in the RAM 608.

FIG. 5 is a main flowchart according to the first embodiment of the present invention. In step S100, the position of the shift select lever is detected by a shift select lever switch (not shown). In step S101, the oil temperature in the hydraulic control device 3 detected by the oil temperature sensor 4e is read, and in step S102, the line in the hydraulic control device 3 detected by the oil pressure sensor 4f is read. In S103, the throttle opening Th detected by the throttle opening sensor 4d provided in the throttle valve for controlling the intake air amount of the engine is read. In step S104, based on the signals of the engine shaft speed sensor 4a, the input shaft speed sensor 4b of the transmission 2, and the output shaft speed sensor 4c,
The engine rotation speed Ne, the transmission input shaft rotation speed Nt, and the transmission output shaft rotation speed No (corresponding to the vehicle speed) are calculated. In step S105, a transmission input shaft torque Tt is calculated from the engine rotation speed Ne and the transmission input shaft rotation speed Nt calculated in step S104. Step S10
In step 6, the target shift speed corresponding to the vehicle running state is read from the throttle opening Th read in step S103 and the transmission output shaft rotation speed No calculated in step S104 from the shift pattern map previously set in the ROM 607. In step S107, the current gear position of the transmission is read from the gear position data achieved in the previous gear shift stored in the RAM 608, and compared with the target gear speed read in step S106, it is determined whether or not gear shifting is to be performed. For example, the process returns to the beginning of the main routine, and if YES, the process proceeds to step S108. In step S108, step S
Shift select lever position and RA read at 100
It is determined whether the ND or NR shift should be performed from the position of the previous shift select lever stored in M608, and if YES, the process proceeds to step S110 to execute the ND or NR shift control subroutine. If NO, the process proceeds to step S109. In step S109, it is determined whether to perform the pre-stop shift based on the target shift speed read in step S106. If YES, step S1 is executed.
11 to execute the pre-stop shift control subroutine,
If NO, the process proceeds to step S112 and ND, NR
And a shift control subroutine other than the shift before stop is executed.

FIG. 6 shows N in Embodiment 1 of the present invention.
It is a flowchart of -D / NR and a shift control subroutine before stop. In step S200, the ROM
Based on the map set in step S607, step S105 in FIG.
The duty base value D0 in the duty drive control for the solenoid valve is read in accordance with the load of the engine such as the transmission output shaft torque calculated in step (1). Step S2
In FIG. 5, a map previously set in the ROM 607 is used.
The correction coefficient for the duty base value read in step S200 is read from the line pressure in the hydraulic control device 3 read in step S102. Step S20
In step 2, the duty base value read in step S200 is multiplied by the correction coefficient read in step S201 to obtain an output duty D for driving the solenoid valve.
Is calculated.

[0043]

As described above, the control device for the automatic transmission according to the first aspect of the present invention corrects the duty drive control to the solenoid valve in accordance with the line pressure in the hydraulic control device at the time of shifting. As a result, the accuracy of the correction to the duty drive control for the change in the line pressure can be improved, and the shock at the time of shifting can be improved.

Further, the control device for the automatic transmission according to the second aspect of the present invention corrects the duty drive control to the solenoid valve according to the line pressure in the hydraulic control device during the ND shift. In addition, it is possible to improve the accuracy of the correction to the duty drive control with respect to the change of the line pressure, and to improve the shock at the time of shifting.

Further, the control device for the automatic transmission according to the third aspect of the present invention corrects the duty drive control to the solenoid valve according to the line pressure in the hydraulic control device during the NR shift. In addition, it is possible to improve the accuracy of the correction to the duty drive control with respect to the change of the line pressure, and to improve the shock at the time of shifting.

Further, the control device for the automatic transmission according to the fourth aspect of the present invention corrects the duty drive control to the solenoid valve according to the line pressure in the hydraulic control device at the time of shifting before stopping. In addition, it is possible to improve the accuracy of the correction to the duty drive control with respect to the change of the line pressure, and to improve the shock at the time of shifting.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a main configuration of a control device for an automatic transmission according to a first embodiment of the present invention.

FIG. 2 is a forward view 4 applied to the first embodiment of the present invention.
FIG. 2 is a skeletal view showing a gear transmission of the automatic transmission capable of achieving the first reverse speed.

FIG. 3 is a hydraulic circuit diagram of the hydraulic control device for the automatic transmission applied to the first embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of an electronic control device applied to the first embodiment of the present invention.

FIG. 5 is a main flowchart according to the first embodiment of the present invention.

FIG. 6 is a flowchart of an ND / NR and a pre-stop shift control subroutine according to the first embodiment of the present invention.

FIG. 7 is a diagram showing a relationship between an engine rotation speed and a line pressure in a conventional device.

FIG. 8 is a diagram showing a relationship between duty drive control (duty ratio) of a solenoid valve and hydraulic pressure in a conventional device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Engine 2 Transmission 3 Hydraulic control device 4 Electronic control device 4a Engine rotation speed sensor 4b Input shaft rotation speed sensor of transmission 2 4c Output shaft rotation speed sensor of transmission 2 4f Oil pressure sensor 12 Torque converter 2A Hydraulic friction element 2B Gear transmission 28 OD clutch 30 UD clutch 32 R clutch 44 L & R clutch 54 2-4 brake 86 Oil pump 400A L & R solenoid valve 400B 2-4
Solenoid valve 400C UD solenoid valve 400D OD solenoid valve

Claims (4)

[Claims] 1. An automatic transmission having a shift select lever which can be shifted by a hydraulic operation of a selected friction element and manually switches between a plurality of ranges such as a traveling range and a neutral range. Automatic transmission characterized in that the line pressure in the hydraulic control device detected by the pressure sensor mounted in the device is taken into the control device, and the duty drive control to the solenoid valve is corrected according to the taken line pressure. Machine control device. 2. A hydraulic control which is detected by a pressure sensor mounted in a hydraulic control device during a shift (hereinafter referred to as an ND shift) when a shift select lever is switched from a neutral range to a drive range. 2. The control device for an automatic transmission according to claim 1, wherein a line pressure in the device is taken into a control device, and a duty drive control to a solenoid valve is corrected according to the taken line pressure. 3. A hydraulic control detected by a pressure sensor mounted in a hydraulic control device during a shift (hereinafter referred to as an NR shift) when the shift select lever is switched from a neutral range to a reverse range. 2. The control device for an automatic transmission according to claim 1, wherein a line pressure in the device is taken into a control device, and a duty drive control to a solenoid valve is corrected according to the taken line pressure. 4. A pressure installed in a hydraulic control device during a shift to a first speed (hereinafter referred to as a shift before stop) in a shift to a low speed in which the engine is decelerated when the hydraulic friction element is released. 2. The automatic transmission according to claim 1, wherein a line pressure in the hydraulic control device detected by the sensor is taken into the control device, and a duty drive control to the solenoid valve is corrected according to the taken line pressure. Control device.