JPH0830528B2 - Automotive automatic transmission - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic transmission of an automobile, and more specifically, to detection from a vehicle speed-throttle valve opening characteristic of an upshift and a downshift for a plurality of stored shift speeds. The present invention relates to an automatic transmission that specifies a shift speed that allows a shift based on the determined current vehicle speed and a current throttle valve opening, and determines the next shift speed based on the current shift speed from the permitted shift speeds.

(Prior Art) A conventional automatic transmission for a vehicle is described, for example, on pages 238 to 251 of Automotive Engineering Complete Volume 9, "Power Transmission Device" (published on November 20, 1980, Sankaido). What has been done is known. The automatic transmission of this automobile is configured to include a torque converter and a speed change gear mechanism in which constituent elements are connected via a clutch.
Shift positions such as R, N, D4, D3, 2 are set.

This type of automatic transmission, as is well known, when the shift lever is operated to the forward automatic shift position such as D4 or D3,
The clutch is automatically engaged and disengaged at a shift point determined by the valve opening degree of the throttle valve (accelerator pedal depression amount) and the vehicle speed to shift gears. This shift point is set to a shift characteristic (shift schedule) according to the performance of the engine mounted on the vehicle, the specifications of the vehicle body, etc., so that each vehicle can obtain an appropriate gear ratio.

(Problems to be Solved by the Invention) However, in such an automatic transmission of an automobile, the shift point is unique depending on the vehicle speed and the valve opening of the throttle valve at the time of upshift and downshift respectively. However, there is a problem that the degree of freedom in setting the shift characteristic is small and it is difficult to set the shift characteristic according to the running condition of the automobile. Particularly in an automatic transmission capable of selecting a shift mode proposed in recent years, it is indispensable to change the shift characteristics, and therefore, there has been a demand for solving the above-mentioned problems.

The present invention has been made in view of the above circumstances, and determines upper and lower limit shift speeds that allow a shift from the detected current vehicle speed and the current throttle valve opening, and determines the shift speed between the upper and lower limit from the current shift speed. It is intended to provide an automatic transmission for an automobile that determines the next gear shift stage based on the above, and to obtain a large degree of freedom in gear shift characteristics.

(Means for Solving the Problems) The present invention detects the vehicle speed and the valve opening of the throttle valve, and shifts between elements of the transmission gear mechanism according to a predetermined shift schedule determined by the vehicle speed and the valve opening of the throttle valve. In an automatic transmission of an automobile that selectively makes and disconnects and fluctuates, an upshift vehicle speed for each of a plurality of shift speeds
Throttle valve opening characteristics and downshift vehicle speed −
A storage means for storing the throttle valve opening characteristic and an allowable upshift vehicle speed-throttle valve opening characteristic for a plurality of shift stages stored in the storage means based on the detected current vehicle speed and the current throttle valve opening Minimum shift speed determining means for determining the minimum shift speed, and downshift vehicle speed-throttle valve opening for a plurality of shift speeds stored in the storage means based on the detected current vehicle speed and current throttle valve opening. A maximum speed shift determining means for determining an allowable maximum speed shift stage from characteristics, an allowable maximum speed shift stage determined by the maximum speed shift stage determining means, and a minimum allowable shift stage determined by the minimum speed shift stage determining means; And a gear shift stage selecting means for selecting one gear shift stage from the gear shift stages included between and based on the limit gear shift stage.

(Operation) According to the automatic transmission of the vehicle according to the present invention, at least the shift is allowed by defining the allowable maximum speed and the minimum allowable speed based on the detected current vehicle speed and the current throttle valve opening. One shift speed is specified, and one selected from the specified shift speeds based on the current shift speed is determined as the next shift speed. Therefore, the gear shift characteristic can be arbitrarily set by adjusting the gear shift stage that allows the gear shift specified by the current vehicle speed and the current throttle valve opening, and a great degree of freedom can be obtained in determining the gear shift characteristic. Since the permissible shift speed can be adjusted by changing the vehicle speed-throttle valve opening characteristics for upshifting and downshifting, a large storage capacity is not required for the storage means, and the size can be reduced and the manufacturing cost can be reduced.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

1 to 7 show an automatic transmission for an automobile according to an embodiment of the present invention. FIG. 1 is a skeleton diagram of a power transmission system, FIG. 2 is a hydraulic circuit diagram, FIG. 3 and FIG. FIG. 5, FIG. 5 and FIG. 6 are flowcharts, and FIG. 7 is a diagram showing a data table.

First, the outline will be described with reference to FIG. 1. The engine (E) is an engine, and the engine (E) has a crankshaft (1), a torque converter (T), a transmission gear mechanism (M), and a differential device (Df). ) Etc. are connected to the left and right drive wheels (W).

As is well known, the torque converter (T) has a pump impeller (2), a turbine runner (4) and a stator (5), and the output of the engine (E) input to the pump impeller (2) is generated by the action of fluid. Output from the turbine runner (4) to the speed change gear mechanism (M). The torque converter (T) is provided with a direct coupling clutch (Cd) between the pump impeller (2) and the turbine runner (4), which is capable of directly coupling the turbine runner (4) and the pump impeller (2). The direct coupling clutch (Cd) is supplied with hydraulic pressure from a hydraulic control circuit described later to directly couple the pump impeller (2) and the turbine runner (4). The details of the torque converter (T), and the details of the speed change gear mechanism (M) and the hydraulic control circuit described below, are set forth in the patent application filed by the applicant of the present application on June 13, 1985. Name; the method for controlling the direct coupling mechanism of the hydraulic power transmission device of the automatic transmission for a vehicle)
The following description will be simplified.

The transmission gear mechanism (M) includes a main shaft (3) connected to a turbine runner (4) of the torque converter (T).
And counter shaft (16) connected to the differential (Df)
Are arranged in parallel with each other, and five gear trains (G1), (G2), corresponding to the number of gear stages, are provided between the shafts (3), (16).
(G3), (G4), and (Gr) are installed in parallel. The forward first speed gear train (G1) includes a drive gear (17) connected to a main shaft (3) through a first speed clutch (C1) and a counter shaft (7) meshed with the drive gear (17). Driven gear (18) that can be connected to 16) via one-way clutch (Co)
And have. Similarly, the gear train (G2) for second forward speed is attached to the main shaft (3) by the second speed clutch (C).
A gear train for the third forward speed, which comprises a drive gear (19) connected via 2) and a driven gear (20) fixed to the counter shaft (16) and meshing with the drive gear (19). (63)
Is a drive gear (21) fixed to the main shaft (3)
And a driven gear (2 which is connected to the counter shaft (16) through the third speed clutch (C3) and meshes with the drive gear (21).
2) and a gear train for fourth forward speed (G4)
Is a drive gear (23) connected to the main shaft (3) through the fourth speed clutch (C4) and the main shaft (3), and a counter gear (16) through a switching clutch (Cs). And a driven gear (24) meshing with (23). Further, the reverse gear train (Gr) includes a drive gear (25) provided integrally with the drive gear (23) of the fourth speed gear train (G4), and the switching clutch (Cs) on the counter shaft (16). ) And driven gears (26) and both gears (2)
5) and idler gear (27) meshing with (26). Each clutch (C1), (C2), (C3), (C
4) is connected to the hydraulic control circuit, and connects and disconnects according to the hydraulic pressure supplied from the hydraulic control circuit. Switching clutch (Cs)
Is provided in the middle of the driven gear (24) and the idle gear (27) of the fourth speed gear train (G4), and the selector sleeve (S) of the clutch (Cs) is shown in FIG. This is because the driven gear (24) and the idle gear (27) are selectively connected to the counter shaft (16) by shifting to the left forward position or the right backward position. The one-way clutch (Co) transmits only drive torque from the engine (E) to the drive wheels (W), and does not transmit torque in the opposite direction.

This transmission gear mechanism (M) has a selector sleeve (S)
As shown in FIG. 1, if only the first speed clutch (C1) is connected when the vehicle is held at the forward position, the drive gear (17) is connected to the main shaft (3) and the first speed gear (17) is connected. The train (G1) is established, and torque is transmitted from the main shaft (3) to the counter shaft (16) through the gear train (G1). If the second speed clutch (C2) is connected while the first speed clutch (C1) is still connected, the drive gear (19) is connected to the main shaft (3) and the second speed gear train (G2 ) Is established, and torque is transmitted from the main shaft (3) to the counter shaft (16) via the gear train (G2). At this time, the first speed clutch (C1) is also engaged, but the first speed clutch (Co) moves
The second speed gear train (G2) is established instead of the third speed,
The same applies to the fourth speed and the fourth speed. Second speed clutch (C2)
Is released and the third speed clutch (C3) is connected, the driven gear (22) is connected to the counter shaft (16) to establish the third speed gear train (G3), and the third speed clutch ( C
When 3) is released and the fourth speed clutch (C4) is connected, the drive gear (23) is connected to the main shaft (3) and the fourth speed gear train (G4) is established. Further, by moving the selector sleeve (S) of the switching clutch (Cs) to the right in FIG. 1,
If only the fourth speed clutch (C4) is connected, the drive gear (23) is connected to the main shaft (3), the driven gear (24) is connected to the counter shaft (16), and the reverse gear train (Cr) is connected. Is established, and the reverse torque is transmitted from the main shaft (3) to the counter shaft (16) via the gear train (Gr).

The torque transmitted to the counter shaft (16) is transmitted from the output gear (28) provided at the end of the shaft (16) to the large diameter gear (Dg) of the differential device (Df). The gear (Dg)
One end of the speedometer cable (30) is fixed to the gear (29) meshing with the gear (Ds) fixed to the vehicle. The magnet (31a) of the vehicle speed sensor (31) is attached to the other end of the speedometer cable (30). ) Is connected to the speedometer (32), and the speedometer (32) is connected to the gears (Ds), (29).
And it is driven through the cable (30) and displays the vehicle speed. The vehicle speed sensor (31) is the magnet (31a).
And a reed switch (31b) driven by the magnet (31a), and the reed switch (31b) is opened and closed by the magnet (31a) rotating together with the speedometer cable (30). The OFF signal is supplied to the electronic control unit described later.

 FIG. 2 shows a hydraulic control circuit.

In the figure, (P) is the aforementioned hydraulic pump that pressurizes and discharges the hydraulic oil in the reservoir (R), and the hydraulic pump (P) is a regulator valve (Vr), a manual valve (Vm) and a governor valve ( Discharge pressure oil to Vg). The regulator valve (Vr) has a spool (62a) and a port (60b) that is supplied from the pump (P) with pressure oil and a spring (62b).
In response to the elastic force of the torque converter (T), the on / off valve (230) and the timing valve, a portion of the pressure oil supplied from the pump (P) to the ports (60a) and (60b) from the port (60c). The hydraulic pressure supplied to the manual valve (Vm) and the like is supplied to the reservoir (R) from the port (60d) and is supplied to the (210) to regulate the line pressure (Pl). Note that (25
3) is a relief valve installed in the port (60d) of the regulator valve (Vr).

As is well known, in the torque converter (T), the supplied pressure oil flows from the pump impeller (2) through the stator (5) toward the turbine runner (4), and torque is transmitted through the pressure oil. To do. This torque converter (T)
The oil pressure is returned to the reservoir (R) via the pressure maintaining valve (250) and the oil cooler (260). The pressure maintaining valve (250) uses the governor pressure (described later) generated by the governor valve (Vg) at the port (25
0b), the spool (251) responds to the governor pressure and the elastic force of the spring (252) to give resistance proportional to the vehicle speed to the pressure oil from the torque converter (T) flowing into the port (250a). From the port (250c) to the reservoir (R). The pressure maintaining valve (250) functions to reduce the internal pressure of the torque converter (T) at the high vehicle speed position.

In the manual valve (Vm), the spool (71) responds to the manual operation of the shift lever, and the drive position (P), the reverse position (R), the neutral position (N), and the forward four-speed automatic shift position (D).
4), each of the clutches (C1), (C2), (C3), (according to the six shift positions of the automatic shift position (D3) for the third forward speed except the fourth speed and the fixed position (2) for the second speed C4) and each port (70a) to (70) connected to the servo piston (90), etc.
n) is selectively opened and closed. For example, when the shift lever is operated to the N position, the manual valve (Vm) moves to the spool (71).
Is at the position shown in the figure and closes the port (70b), and connects all other ports (70a), (70c) to (70n) to the drain port (EX). Therefore, as is clear from the figure, the clutches (C1), (C2),
No pressure oil is introduced into (C3) and (C4), and these clutches (C1) to (C4) are placed in the disengaged state. Also,
For example, when the shift lever is operated to the (D4) position, the spool (71) moves left by one position in the figure, and the servo piston (90), the first throttle valve (Vt) and the pressure reducing valve (27).
The port (170c) connected to 0) and the port (70h) connected to the flow control valve (400) and the non-creep valve (Vc) are connected to the port (70b) connected to the pump (P), and Port (70 that contacted the speed clutch (C2)
g) communicates with the port (70f) that communicates with the second shift valve (V2), and further communicates with the port (70k) that communicates with the fourth speed clutch (C4) and the timing valve (210) and the second shift The ports (70m) and (70n) connected to the valve (V2) are isolated from the port (70i) and communicate with each other. It should be noted that description of the case where the shift lever is operated to another position is omitted.

Servo piston (90) has its ports (90a), (9
0b), (90c), animal valve (Vm) port (70i),
Pressure oil is introduced from (70c) and (70a), and spool (91
a) pressure of the chamber communicating with port (90b), port (90
It is displaced according to the pressure of the chamber communicating with c) and the elastic force of the spring (91b). In this servo piston (90), the right end of the spool (91a) in the figure is the aforementioned switching clutch (Cs).
When the line pressure (Pl) is introduced into the port (90b) through the manual valve (Vm), the selector sleeve (S) is held at the position shown in FIG. The driven gear (24) of the fourth speed gear train (G4) is connected to the counter shaft (16).

The governor valve (Vg) guides the discharge oil of the pump (P) to the port (80a), regulates the discharge oil to a pressure (governor pressure (Pg)) proportional to the vehicle speed, and then adjusts the pressure from the boat (80b) to the second position. Output to the shift valve (V2), the modulator valve (220) and the pressure holding valve (250).

The first throttle valve (Vt) has a second spool (102) connected via a spring (103) to a first spool (101) engaged with a cam (104) interlocking with the throttle valve. Driven by the cam (104) together with the spool (101), the pressure oil supplied from the manual valve (Vm) to the port (100a) is regulated to adjust the valve opening of the throttle valve, that is, the accelerator pedal depression amount. Proportional pressure (throttle pressure (Pt)) is generated at ports (100b) and (100c). The throttle pressure (Pt) generated by the first throttle valve (Vt) is the second accumulator (170), the fourth accumulator (190), the modulator valve (220), the on / off valve (230), the flow control valve (400 ), A first control valve (160), a second control valve (161) and a third control valve (16).
It is output to 2). Also, this first throttle valve (V
t)) changes the flow passage area between the drain port (EX) and the port (100d) in which the first spool (101) is displaced and communicated with the second shift valve (V2). It alleviates shift shock when downshifting.

The pressure reducing valve (270) is well known, and the pressure oil of the line pressure (Pl) introduced from the manual valve (Vm) to the port (270a) is decompressed to move from the port (270b) to the first shift valve (V1). Output.

In the flow control valve (400), the port (400a) is the first shift valve (V1), the ports (400b) and (400c) are the manual valves (Vm), and the port (400d) is the throttle valve (Vt). )
And the spool (401) is introduced from the throttle valve (Vt) and the throttle pressure (Pt) and spring (40
2) Adjust the flow rate supplied to the first shift valve (V1) in response to the elastic force. This flow control valve (400) controls the amount of oil supplied to the first shift valve (V1) in proportion to the throttle pressure (Pt) to prevent a plurality of clutches from being in the connected state at the same time, and a shift shock. To reduce.

The first shift valve (V1) has a port (120a) connected to the pressure reducing valve (270), a port (12b) connected to the first solenoid valve (140) that is in constant communication with the port (120a), The port (120c) opened to the drain (EX) and connected to the second control valve (161), the ports (120d) and (120e) connected to the second shift valve (V2), and the drain (EX ) Has a port (120f) connected to the second throttle valve (110) and a port (120g) connected to the flow control valve (400), and is opened by the first solenoid valve (140). Controlled port (120b) oil pressure or port (27
0b), the spool (121a) responds to the hydraulic pressure in the chamber communicating with the spring (121b) and the elastic force of the spring (121b), and the ports (120c), (12
0d), (120e), (120f) and (120g) are selectively connected. That is, at the illustrated position where the spool (121a) is at the right end in the figure, the ports (120c) and (120d) and the ports (120e) and (120g) communicate with each other, and the spool is displaced to the left end in the figure. At the port (120d) (12
0g) and ports (120e) and (120f) communicate.
A solenoid (140a) of the first solenoid valve (104) is connected to an electronic control unit described later, and opens when the solenoid (140a) is energized to open the port (120) of the first shift valve (V1).
Open b) to drain (EX).

In the second throttle valve (110), the spool (111) engaged with the cam (113) communicating with the throttle valve is driven by the cam (113) and displaced against the elastic force of the spring (112). The flow passage area is continuously changed between the port (110a) connected to the first shift valve (V1) and the drain port (EX) opened to the reservoir (EX). This second
The throttle valve (110) of the first shift valve (V1) adjusts the pressure of the port (120f) to change the speed from the fourth speed to the third speed.
Reduces shift shock when shifting down to high speed.

The second shift valve (V2) includes a port (130a) connected to the governor valve (Vg), a port (130b) connected to the first throttle valve (Vt), and a first shift valve (V1). Port (130c) connected to port (120d), Port (130d) connected to second solenoid valve (150), Port (130e connected to port (120e) of first shift valve (V1) ),
Port (130f) connected to the animal valve (Vm) port (70f), Manual valve (Vm) port (70m), (70n)
Port (130g), port (70a) of the manual valve (Vm), port (130i) opened through the first control valve (160), and third speed clutch It has a port (130h) connected to (C3), and the spool (131) responds to the hydraulic pressure in the room at the right end in the figure and the elastic force of the spring (132) communicating with the ports (130a) and (130d). . The second shift valve (V2) has a port (130b) and a port (130h), a port (130c) and a port (130f), and a port (when the spool (131) is at the right end position in the drawing. 130g) and drain port (EX)
, And when the spool (131) is at the left end position in the figure, the port (130c) and port (130h),
Port (130f) and port (130k) and port (130e)
And the port (130g). In the second shift valve (V2), the hydraulic pressure of the ports (130a) and (130b), that is, the movement of the spool (131) is controlled by the second solenoid valve (150), and the second solenoid valve (150) is controlled. When opening the valve,
When the second solenoid valve (150) is closed, the position at the left end in the figure is taken. Incidentally, (133) is a click motion mechanism for selectively limiting the position of the spool (131).

The non-creep valve (Vc) is a port (300a), (300b) connected to the manual valve (Vm), and a third solenoid valve (310).
Port (300c), which was connected to the manual valve (Vm) via
The spool (301) has a port (300d) connected to the first speed clutch (C1) and a port (300e) connected in parallel to the check valve (50v) and the third control valve (162). Pressure difference between ports (300a) and (300e) and spring (30
It responds to the elastic force of 2). The spring (302) is contracted between the bolt (303) fastened by the lock nut (304) and the spool (301), and is changed to the spool (301) by changing the screwing length of the bolt (303). The elastic force applied is adjusted. This non-creep valve (Vc) is equipped with a port (3
00c) is closed to communicate between the port (300b) and the port (300d), and when the spool (301) is at the upper end position in the figure, the port (300c) is further drain port (EX).
Communicate with The third solenoid valve (310) is a solenoid (310
a) is connected to the electronic control unit and opens when the solenoid (310a) is energized.

The third control valve (162) guides the throttle pressure (Pt) to the port (300e) of the non-creep valve (Vc) when the throttle pressure (Pt) is small, but when the throttle pressure (Pt) is large, the line pressure (Pl) ) Lead.

The timing valve (210) includes a port (210a) connected to the second speed clutch (C2), a port (210b) connected to the fourth speed slat (C4), and a port (210) connected to the regulator valve (Vr). 210c), a port (210d) connected to the inlet port of the torque converter (T) and two ports (210e) and (210f) connected to the modulator valve (220).
The spool (211) responds to the elastic force of the spring (212) and the pressure of the ports (210a) and (210b). This timing valve (210) has a spool (211) that moves to the left in the drawing when the second speed clutch (C2) or the fourth speed clutch (C4) is in the engaged state to take the position at the left end in the drawing. When the high speed clutch (C2) or the fourth speed clutch (C4) is in the released state, the spool (211) moves to the right in the drawing to take the illustrated position at the right end in the drawing. The timing valve (210) communicates between the ports (210c) and (210e) at both the left end and the right end in the figure, but the ports (210c) and (210e) are in the middle of the transition.
Shut off the space between them and connect the port (210f) to the drain port (E
X) isolated from.

The modulator valve (220) is the first throttle valve (V
port (220) from which throttle pressure (Pt) is introduced
a), the port (220b) where the governor pressure (Pg) is introduced from the governor valve (Vg) and the timing valve (210) 2
Has two ports (220c) and (220d), a port (220e) connected to the on / off valve (230) and a port (220f) connected to a direct coupling clutch (Cd), and the spool (221) has a direct coupling clutch (Cd). ) Internal pressure, throttle pressure (Pt) and governor pressure (Pg), and outputs a pressure proportional to the vehicle speed and the valve opening of the throttle valve to the on / off valve (230).

The on / off valve (230) is connected to the first throttle valve (Vt) and the port (23) where the throttle pressure (Pt) is introduced.
0a), the port connected to the regulator valve (Vr) (230
b), a port (230c) connected to the inlet port of the torque converter (T), a port (230d) connected to the outlet port of the torque converter (T), and a port (230e) connected to the modulator valve (220) With spool (231) throttle pressure (Pt) and spring (232)
Responds to the elastic force of. This on / off valve (230) connects the port (230a) to the drain port (EX) and connects the ports (230b) and (230c) directly during idle operation of an engine with a low throttle pressure (Pt). The amount of oil supplied to the torque converter (T) is increased while releasing the clutch (Cd).

The direct coupling clutch (Cd) is controlled by this fourth solenoid valve (240), whose outlet port is also in communication with the fourth solenoid valve (240). The fourth solenoid valve (240) has a solenoid (2
40a) is connected to the electronic control unit and solenoid (240a)
When is energized and excited, the port (241) connected to the direct coupling clutch (Cd) is opened to the drain port (EX) to shift the direct coupling clutch (Cd) to the released state.

The second speed clutch (C2) is connected in parallel with the second accumulator (170), and the third speed clutch (C3) is connected in parallel with the third accumulator (180) and the first control valve (160). The fourth speed clutch (C4) is connected in parallel with the fourth accumulator (190) and the second control valve (161). As is well known, each accumulator (17
0), (180), and (190) reduce shift shock, and the first control valve (160) and the second control valve (161) determine the characteristics when the clutch is released. In addition, in FIG. 2, (CH) represents a diaphragm.

(800) is an electronic control unit equipped with a one-chip microcomputer, etc. This electronic control unit (800) stores the shift schedule in ROM and detects the vehicle speed by the aforementioned vehicle speed sensor (31) and throttle valve valve. The above-mentioned solenoid valves (140), (150), (240), (310), etc. are connected together with various sensors such as an accelerator sensor (803) for detecting the opening degree, and the solenoid valves are based on the output signal of each sensor. Energization control is performed. The electronic control unit (800) corresponds to a storage means, a lowest speed shift stage determination means, a highest speed shift stage determination means, and a shift stage selection means.

Such a hydraulic control circuit, as shown in the table below,
And solenoids (14) of the second solenoid valves (140), (150)
0a), (150c) are selectively energized by the electronic control unit (800) to open the valves, and the clutches (C1), (C2), (C
3) and (C4) are controlled to establish one of the first speed to the fourth speed of the transmission gear mechanism (M) according to the vehicle speed and the opening of the throttle valve.

Next, the operation of this embodiment will be described.

The automatic transmission of this automobile is controlled by the electronic control unit (800) repeatedly executing a series of processes shown in the flowcharts of FIGS. 3, 4, 5, and 6 at predetermined intervals.

First, when the ignition switch is turned on, initialization (initialization) processing of the CPU of the electronic control unit (800) is performed in step (P1). In the next step (P2), it is determined whether or not the engine (E) is operating by itself, that is, the engine speed (Ne) of the engine (E) is a predetermined engine speed (Neo) (for example, 300
[Rpm]) is exceeded, and the engine (E) rotational speed (Ne) exceeds a predetermined rotational speed (Neo) and the engine (E) is in operation, the process proceeds to step (P3). If the engine speed (Ne) of the engine (E) is equal to or lower than the predetermined engine speed (Neo), the process proceeds to step (P4).

In step (P3), input data is read from various sensors such as the vehicle speed sensor (31), and in subsequent step (P5), input data processing such as storage of input data is performed. Then, in the next step (P6), the speed ratio (e) of the torque converter (T) is calculated. The speed ratio (e) is obtained as a ratio between the rotation speed of the turbine runner (4) and the rotation speed of the pump impeller (2). In the subsequent step (P7), non-creep control is performed based on the vehicle speed data and the like. In this step (P7), the current to be applied to the solenoid (310a) of the third solenoid valve (310) is determined, and the energization control of the third solenoid valve (162) is performed by the output process of step (P11) described later. Adjust the hydraulic pressure supplied to the 1st speed clutch (C1).

In the next step (P8), the processing shown in the flowcharts of FIGS. 4, 5, and 6 described later is executed to perform the shift control, and thereafter, in step (P9), in the aforementioned step (P6). The capacity of the direct coupling clutch (Cd) is controlled based on the calculated speed ratio (e) and the like.

On the other hand, in the above-mentioned step (P4), the process of maintaining the shift stage of the automatic transmission at the third forward speed is performed, and the subsequent step (P1
0) to release the clutch (Cd).

Thereafter, in step (P11), output processing such as energization of the solenoid valve is performed based on the processing results of the above-described steps. Then, after the processing of this step (P11) is completed, the series of processing from step (P2) is repeatedly executed again.

The shift control in step (P8) is performed by executing the processing shown in the flowchart of FIG. First,
After performing a map search in step (Q1),
Decode the shift schedule retrieved from the map in 2). The process of step (Q1) will be described later with reference to FIG. 5, and the process of step (Q2) will be described later with reference to FIG. In the next step (Q3), the control signal (internal signal) of the direct coupling clutch (Cd) is output based on the result of decoding the shift schedule, and in the subsequent step (Q4), the shift command (internal command) is output.

The map search is performed as shown in FIG. First, a specific example of the map will be described. As shown in FIG. 7, this map is for forward four speeds, and upshift lines (fu1), (fu2), (fu3) (hereinafter, The number is represented by n, f
represented by un) and downshift lines (fd1), (fd
2) and (fd3) (hereinafter, represented by fdn) partition the permissible area for each shift speed (1), (2), (3), and (4). Some of these areas overlap, for example:
The shift permitted region of the shift stage (3) defined by the downshift line (fd2) and the upshift line (fu3) is defined by the downshift line (fd1) and the upshift line (fu2). The shift range of the gear (2) is defined by the allowable range and the downshift line (fd3) defined by the shift range (4).
3) and the upshift line (fu2) overlap. That is, in the region defined between the downshift line (fd3) and the upshift line (fu2), the shift speeds (2), (3),
The gear shift of (4) is allowed.

To search for a map using such a map, first, in step (R1), set 1 to the variable (n) for counting the number of executions.
Then, in the next step (R2), it is determined whether or not the vehicle speed (V) is lower than the determined vehicle speed (Vθu-n) according to the upshift line (fun) based on the throttle valve opening. Naturally, the upshift line (fu1) is specified by the step (R2), and the upshift line (fu2), (fu3) is sequentially specified by the step (R4) described below.
Is specified. In this step (R2), if it is determined that the vehicle speed (V) is lower than the vehicle speed (Vθu-n), the process proceeds to step (R5) described later, and the vehicle speed (V) is equal to or higher than the vehicle speed (Vθu-n). If it is determined that, 1 is added to the variable (n) in step (R3). And the following steps (R
In 4), it is judged whether or not the variable (n) is smaller than 4 corresponding to the number of gears, and if the variable (n) is smaller than 4, the processing from step (R2) is repeated, and the variable (n) is also repeated. If is 4 or more, proceed to step (R5). In this step (R5), the variable (n) is set as the allowable lowest speed shift stage (Sl).

Next, in step (R6), the variable (n) is set to 1, and in subsequent step (R7), the vehicle speed (V) is determined according to the downshift line (fdn) based on the throttle valve opening (Vθd). -N) It is determined whether it is smaller than. When it is determined in this step (R7) that the vehicle speed (V) is lower than the vehicle speed (Vθd-n), the process proceeds to step (R10) described later, and the vehicle speed (V) is equal to or higher than the vehicle speed (Vθd-n). If it is judged that the step (R
In step 8), add 1 to variable (n). Subsequent steps (R9)
Then, it is judged whether or not the variable (n) is smaller than the corresponding number 4 in the number of gear stages, and if the variable (n) is smaller than 4, the processing from step (R7) is repeated again, and the variable (n) is also repeated.
If is 4 or more, proceed to step (R10). Step (R
In 10), the variable (n) is set as the allowable maximum speed (Sh).

Subsequently, the gear stage is designated as shown in FIG. First, in step (T1), it is determined whether the allowable maximum speed (Sh) and the allowable minimum speed (Sl) determined by executing the above-described routine are the same, and the maximum allowable speed and If the minimum permissible shift speeds (Sh) and (Sl) are the same, the process proceeds to step (T6), and if the upper and lower limit shift stages (Sh) and (Sl) are different, the process proceeds to step (T2). In step (T2), it is determined whether or not the current gear stage (So) is the same as or lower than the allowable lowest speed gear stage (Sl). If the gear is lower than the gear (Sl), the process proceeds to step (T6), and if the current gear (So) is the same as or higher than the gear (Sl) of the allowable minimum speed, the gear is a higher gear. Go to step (T3). In step (T3), similarly, it is determined whether or not the current gear stage (So) is the same as or lower than the allowable maximum speed stage (Sh), and the current gear stage (So) is allowed. If the speed is higher than the highest speed (Sh), proceed to step (T5). If the current speed (So) is the same as or lower than the allowable highest speed, proceed to step (T4). )
Go to. At the step (T4), the current gear (So) is maintained, and at the step (T5), the allowable maximum speed (S) is maintained.
h) is set, and in step (T6), the minimum permissible shift speed (Sl) is set, and these commands are output.

As described above, in the automatic transmission of this embodiment, the upshift and downshift vehicle speed-throttle valve opening characteristics are stored as data for a plurality of shift speeds.
The minimum allowable shift speed is determined from the vehicle speed-throttle valve opening characteristic for upshifting, and the maximum allowable shift speed is determined from the vehicle speed-throttle valve opening characteristic for downshifting. The shift speed of the shift speed between the shift speeds is permitted, and the next shift speed is selected from the shift speeds permitted to shift based on the current shift speed. Therefore, the vehicle speed-throttle valve opening characteristics for upshifting and downshifting are correlated and adjusted for each shift speed, so that the shift characteristics can be set arbitrarily, and the capacity required for storing data is reduced. The cost can be reduced. Further, as shown in FIG. 7 and FIG. 8 which will be described later, the upshift lines (fu1), (fu2), (fu3) and the downshift line (fd1) which are the vehicle speed-throttle valve opening characteristic for each gear position. ), (Fd2), (fd3) are set to direct characteristics, the region is subdivided according to the throttle valve opening and the vehicle speed as proposed by the applicant in Japanese Patent Application No. 61-291759. Even if it is difficult to directly store the allowable shift speed in the area of 1) due to the limitation of the storage capacity, the allowable shift speed can be easily known from the vehicle speed-throttle valve opening characteristic for each shift speed. It also has an effect.

In addition, in the above-described embodiment, the data table having the regions in which the shifting of the three shift speeds is allowed is used as shown in FIG. 7, but it is also possible to use the data table as shown in FIG. . The data table of FIG. 8 has a region in which two shift speeds allowed to shift are included.

(Effects of the Invention) As described above, according to the automatic transmission for an automobile of the present invention, regions in which a plurality of shift speeds are allowed to be shifted are specified by the vehicle speed and the throttle valve opening in an overlapping manner. Since a shift schedule is provided and the shift control is performed based on the detected vehicle speed, throttle valve opening, and current shift stage according to this shift schedule, the shift schedule does not require a large amount of storage capacity, The degree of freedom in setting the characteristics can be increased.

[Brief description of drawings]

1 to 7 show an automatic transmission of an automobile according to an embodiment of the present invention, in which FIG. 1 is a skeleton diagram of a power transmission system, FIG. 2 is a hydraulic circuit diagram, FIG. 3 and FIG. , Figures 5 and 6
FIG. 7 is a flowchart and FIG. 7 is a diagram showing a shift schedule. FIG. 8 is a diagram showing a shift schedule of an automatic transmission for an automobile according to another embodiment of the present invention. E: Engine Cd: Directly connected clutch T: Torque converter M: Speed change gear mechanism (C1), (C2), (C3), (C4), (Cs): Clutch (31): Vehicle speed sensor ( 140), (150), (240) (310) ...... Solenoid valve (800) ...... Electronic control device (storage means, lowest speed shift speed determination means, maximum speed shift speed determination means, shift speed selection means) (803 ) …… Accelerator sensor

Claims (1)

[Claims] 1. A vehicle speed and a valve opening of a slot valve are detected, and a gear shift operation is performed by selectively connecting and disconnecting each element of a transmission vehicle speed mechanism according to a predetermined shift schedule determined by the vehicle speed and the valve opening of the slot valve. In an automatic transmission of an automobile, a storage means for storing an upshift vehicle speed-slot valve opening characteristic and a downshift vehicle speed-slot valve opening characteristic for a plurality of shift speeds, and a detected current vehicle speed and current slot valve Minimum speed shift speed determining means for determining an allowable minimum speed shift speed from an upshift vehicle speed-throttle valve opening characteristic for a plurality of shift speeds stored in the storage means based on the opening, and the detected current vehicle speed and Downshift vehicle for a plurality of shift stages stored in the storage means based on the current slot valve opening A maximum speed shift stage determining means for determining the allowable maximum shift stage from the throttle valve opening characteristic, an allowable maximum shift stage determined by the maximum shift stage determining means, and a minimum shift stage determining means; An automatic transmission for an automobile, comprising: a shift speed selecting unit that selects one shift speed from among the shift speeds included between the allowable minimum speed shift speed and the current minimum shift speed.