JPS622180B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shift change control device for an automatic transmission of an automobile, which achieves shift change control of an automatic transmission of an automobile by electro-hydraulic control.

In general, automatic transmissions using electro-hydraulic control electrically detect vehicle speed, throttle opening, etc., calculate and determine the optimum gear position according to the vehicle's driving conditions, and use the output to operate a solenoid valve. A plurality of hydraulic servo means are selectively operated to obtain a plurality of speed ratios. This method has the drawback that the number of solenoid valves increases depending on the number of gears of the transmission, and the hydraulic control section becomes larger.

Figure 1 shows a conventional torque converter type forward drive 3.
FIG. 1 is a configuration diagram showing an example of an automatic transmission with one reverse gear and one reverse gear, which is composed of a torque converter, a planetary gear mechanism, a hydraulic control mechanism, and an electric control mechanism.
In the exemplary transmission, the first forward speed is the clutch 6
The rotation of the engine is fluidly transmitted by the input shaft 8, pump impeller 2, turbine runner 3, turbine shaft 5, and torque converter 1, and the rotation of the engine is fluidly transmitted to the planetary gear system 11. It is transmitted to input sun gear 9.
At this time, since the carrier 13 is fixed by the brake 21, the pinion shaft 20 is also fixed, and the input rotation is transmitted from the input sun gear 9 via the gears 12 and 17 to the gear 19 of the output shaft 18 at a reduced speed. Incidentally, in the first speed, when the engine is driven from the engine side, the one-way clutch 23 is also operated, so the brake 21 does not necessarily need to be operated, and the brake 21 may be operated only when engine braking is required. Further, 4 indicates the stator of the torque converter.

Second speed is obtained by actuating clutch 6 and brake 22. In this case, the planetary gear system 11
The input to is performed by input sun gear 9,
Since the reverse sun gear 10 is fixed by the brake 22, the rotation of the input sun gear 9 is transmitted to the carrier 13 and gear 19 at a reduced speed.

Third speed is obtained by operating both clutches 6 and 7, and input to the planetary gear system 11 is from both input sun gear 9 and reverse sun gear 10, so the planetary gear system 11 is integrated. The rotation of the turbine shaft 5 and the rotation of the output shaft 18 become the same. For reverse, clutch 7 and brake 2
This is done by the operation of 1. In this case, the carrier 13 and therefore the pinion shafts 14 and 20 are fixed, and the input from the turbine shaft 5 is transmitted to the output shaft 18 via the reverse sun gear 10, idler gear 15, gears 16 and 17, and the output shaft 18 is rotated in reverse rotation. do. Note that 102 is a rotation sensor that detects the rotation of the output shaft, and obtains an electrical output related to the vehicle speed.

FIG. 2 is an example of a conventional device showing only the portion related to the forward automatic gear shift control according to the present invention among the hydraulic circuits that control the operation of each hydraulic servo means, that is, the clutch device and the brake device, of the device shown in FIG. 1. be.

In FIG. 2, a gear position determining circuit 101 is constructed of an electronic circuit to determine the optimum gear position according to the driving conditions of the automobile, and generally detects the rotation speed of the transmission output shaft related to the vehicle speed. a rotation sensor 102 that obtains an electrical signal related to the throttle opening of the engine; and a throttle opening sensor 10 that obtains an electrical signal related to the throttle opening of the engine.
Based on the signal No. 3, the shift change timing as shown in FIG. 5 is obtained, and the 2-3 solenoid 104 and the 1-2 solenoid 105 are turned on and off according to the indicated state. In the configuration shown in Fig. 2, when both the 2-3 solenoid 104 and the 1-2 solenoid 105 are in operation, the first speed is set, and when only the 1-2 solenoid 105 is inactive, the second speed is set. In the non-operating state, it is in the third speed.

106 is 2-3 speed switching valve, 107 is 1-2
It is a quick switching valve. Since both valves have substantially the same construction, only the 2-3 speed switching valve will be described in detail regarding its operation.

Now, when the coil 108 of the 2-3 solenoid 104 is energized by the gear stage determination circuit 101, the plunger 109 is attracted, and the 2-3 spool 110
presses the spring 111 and assumes the position shown in FIG. As a result, ports 112 and 113 are disconnected from each other, and at the same time port 113 is connected to oil drain port 1.
14 and drains oil. On the other hand, when the current in the coil 108 is cut off by the gear position determination circuit 101, the spool 110 is moved to the left in the figure by the spring 111, thereby bringing the ports 112 and 113 into communication.

The operation of the 1-2 switching valve 107 is similar to that of the 2-3 switching valve 106, and the spool 116 moves by pressing the spring 117 due to the operation of the solenoid 105, and the ports 118 and 11
9 is disconnected, and port 119 is connected to oil drain port 12.
0 and when solenoid 105 is inactive, ports 118 and 119 are connected. Note that 115 and 121 are oil drain ports for facilitating movement of the spools 110 and 116.

The operation of the hydraulic control circuit will be explained below based on the operation mode of each of the switching valves.

Reference numeral 122 indicates an engine (not shown), generally a hydraulic pump driven by the shaft of the pump impeller 2, and 123 indicates an oil reservoir to which oil returns via each hydraulic circuit. 124 is a pressure regulating valve that adjusts the oil pressure of the hydraulic pump 122 to a pressure suitable for control; a part of the pressure oil passes through the torque converter 1, is cooled by an oil cooler (not shown), and is returned to the oil reservoir 123; In addition, some of the oil is returned directly to the oil sump. 125 is a manual valve that manually controls the operating state of the transmission, and as is generally known, there are ranges such as forward D, reverse R, parking P, neutral N, hold 2, and L, and the valve is operated according to the range. supply pressure oil to the necessary hydraulic lines. Note that in FIGS. 2 and 3, only the hydraulic lines according to the present invention are shown.

Now, when the manual valve 125 is selected to the forward D range, the clutch 6 is supplied with oil through the manual valve 125 and is constantly operated. On the other hand, the calculation result of the gear stage determining circuit 101 determined by the rotation sensor 102 and the throttle opening sensor 103 is the first
When the speed is instructed, the 2-3 and 1-2 solenoids 104 and 105 are energized, and each switching valve 10
6, 107 is in the illustrated position in FIG. As a result, the clutch 7 is drained of oil through the oil drain port 114 and becomes inoperative, and the brake 22 is drained from the oil drain port 114 and the oil drain port 114 and the brake 22 is in a non-operating state.
Since the oil is drained at 20, the spring 128 makes it inactive. Therefore, as described above, the planetary gear system 11 is in the first speed.

Next, when the second gear is instructed by the gear stage determining circuit 101, the 1-2 solenoid 105 returns to its original state.
The spool 116 of the 1-2 switching valve 107 moves to the left in the figure, and ports 118 and 119 are brought into communication. As a result, the pressure oil being supplied to the port 118 by the manual valve 125 is supplied to the hydraulic chamber 126 of the brake 22 through the port 119.
The spring 128 is compressed and the brake 22 is activated. On the other hand, the clutch 7 is connected to the 2-3 switching valve 1.
06, the oil continues to be drained and the planetary gear system 11 is kept in a non-operating state, and becomes the second speed.

When the vehicle speed further increases and the output of the gear position determining circuit 101 reaches the third speed state, the solenoid 104,
105 are both inactive, and the spool 110 of the 2-3 switching valve 106 also moves to the left in the figure. Therefore, the pressure oil supplied to port 112 through manual valve 125 is transferred to port 1.
13 to operate the clutch 7, and further,
Since the hydraulic pressure is also supplied to the hydraulic chamber 127 of the brake 22, the hydraulic pressure applied to the hydraulic chambers 126 and 127 is balanced, and as a result, due to the action of the spring 128,
Brake 22 is restored. That is, as a result of both clutches 6 and 7 operating, the planetary gear system 1
1 rotates as one, the turbine shaft 5 and the output shaft 18 have the same rotation speed, and enter the third speed state.

As described above, in the conventional system, the number of solenoid valves increases as the number of gears increases, and as the number of gears increases, the size and complexity of the transmission increases.

In order to solve the above-mentioned drawbacks, the present invention disposes a hydraulic switching valve that selectively operates the hydraulic servo means in the hydraulic path between the hydraulic source and the hydraulic servo means, and operates the hydraulic switching valve by a pulse motor. The gear shift operation is achieved by operating a hydraulic distribution valve that is driven by a motor. Even if the number of gears increases, only one hydraulic distribution valve is required, and since the hydraulic distribution valve is driven by a pulse motor, an electronic It is an object of the present invention to provide a speed change control device for an automatic transmission that has a simplified circuit section, is small in size, and has high reliability.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 3 to 5 of the accompanying drawings.

In FIG. 3, the lower two digits of the same operating parts as in FIG. 2 are the same numbers. In FIG. 2 is similar to the 2-3 switching valve 106 and the 1-2 switching valve 107. 2-3 switching valve 206 is a driving hydraulic chamber 229
By supplying pressure oil to the spring 21
1 is compressed to the position shown in FIG. 3, and when the oil is drained, the spool 21 is
0 moves to the left and connects ports 212 and 213. Further, when pressure oil is supplied to the drive hydraulic chamber 230, the 1-2 switching valve 207 is activated by the spring 217.
is compressed, and each oil passage is in the position shown in Figure 3,
When the oil is drained, the spool 216 is moved to the left by the spring 217, and the ports 218 and 219 are communicated with each other.

231 indicates a single hydraulic distribution valve that drives hydraulic switching valves such as switching valves 206, 207, etc.;
232 is a pulse motor, 233 is a rotor, 234
As described later, the drive coil is composed of, for example, four coils, and by applying an appropriate combination of pulse voltages, the rotor 233 is rotated by a fixed rotation angle. The rotor 233 is fitted into a screw 236 provided at one end of a spool 235 of the hydraulic distribution valve 231, and the spool 235 is configured to be movable only in the axial direction but not rotated.

Therefore, the rotor 233 of the pulse motor 232
As the spool 235 rotates, the spool 235 is proportional to the number of pulses applied to the drive coil 234,
Accurately moved in the axial direction. 237 is a port to which the hydraulic pressure regulated by the pressure regulating valve 224 is supplied, and 238 and 239 are output ports of the hydraulic distribution valve 231, which are used to drive the 2-3 switching valve 206 and the 1-2 switching valve 207, respectively. It is connected to chambers 229 and 230. 240 and 241 are connected to the oil reservoir 223 through oil drain ports.

FIG. 4 shows a control circuit for the pulse motor 232 shown in FIG. 3. The drive coil 234 of the pulse motor 232 has four coils 232A,
An example in which B, 232C, and 232D are provided will be explained. In this case, as shown in the table shown in FIG. 4, the pulse motor 232 is controlled one step at a time by applying pulse currents of the combinations shown in the table to each of the drive coils 232A-D and sequentially shifting the combinations. When the spool 2 rotates at the rotation angle and changes the pulse combination from top to bottom, for example,
35 moves downward as shown in FIG. 4, and conversely, when the combination of pulse currents is changed in the order from bottom to top, the spool 235 is moved upward.

Reference numeral 242 denotes a gear position determination circuit that determines the gear position based on the signals from the rotation sensor 102 and the throttle opening sensor 103, and its characteristics are as shown in FIG. 5, similar to the electrical control circuit 101 shown in FIG. be done. Reference numeral 243 is a shift direction determination circuit, which indicates an upshift from 1st speed to 2nd speed, 2nd speed to 3rd speed, or 3rd speed to 2nd speed, or 2nd speed to 1st speed.
Determine whether it is a speed downshift. 244 is a pulse motor 232 based on the signal from the direction discrimination circuit 243.
A drive circuit that drives the spool 235 outputs pulses of a predetermined step according to the direction of change of the pulse combination according to the output state of the direction discrimination circuit 243, drives the pulse motor, and moves the spool 235 by a predetermined amount. Ports 238 and 239 are sequentially connected to oil drain port 2.
Connect to 40.

In the above configuration, the gear stage determination circuit 24
2 indicates the first speed based on the outputs of the rotation sensor 102 and the throttle opening sensor 103, the hydraulic distribution valve 231 is set to be in the state shown in FIG. 23
1 output port 238, 239 both port 237
communicate with. Therefore, the pressure oil whose pressure is regulated by the pressure regulating valve 224 is transferred to the 2-3 switching valve 206, 1-2.
The drive hydraulic chamber 229 of the switching valve 207, and 2
30 and each valve's spool 210,2
16 in the state shown, the clutch 7 and the brake 22 are deactivated and the planetary tooth system 11
is the first speed.

Next, for example, when the vehicle speed increases, the gear position determination circuit 2
42 indicates the second speed, the shift direction determination circuit 243 outputs an upshift signal, and the drive circuit 244 of the pulse motor 232 outputs a pulse in the determined direction, that is, from the bottom to the top of the table in FIG. The combination is changed a predetermined number of times and the pulse motor 232 is rotated. This rotation is spool 2
35 upward movement, and the output port 239 is brought into communication with the oil drain port 240 and stopped. As a result, the drive hydraulic chamber 230 is drained of oil, and the spool 2
16 is moved to the left in the figure by a spring 217, pressure oil is supplied to the brake 22 through ports 218 and 219, and the brake 22 is activated, resulting in second speed. Furthermore, a gear stage determination circuit, 2
42 commands third speed, the same state as the upshift to second speed is repeated, and the hydraulic distribution valve 231
spool 235 is moved upward by a predetermined amount, and port 238 is also connected to oil drain port 240. As a result, the drive hydraulic chamber 229 of the 2-3 switching valve 206
drains the pressure oil, connects ports 212 and 213, operates clutch 7, and on the other hand brake 2
As a result of disabling gear 2, the planetary gear system 11 is in the third speed.

Next, when the gear position determination circuit 242 instructs a change from third speed to second speed or from second speed to first speed, shift direction determination circuit 243 issues a downshift signal, and drive circuit 244 outputs a specified number of pulse combinations. The pulse motor 232 is rotated in the opposite direction to the specified rotation upshift direction, the spool 235 is lowered, and the output port 23
8, and 239 are sequentially connected to port 237,
Each hydraulic servo is activated or deactivated to achieve a gear position according to an instruction from the gear position determining circuit 242.

As described above, the present invention disposes a hydraulic switching valve that selectively operates the hydraulic servo means in the hydraulic path between the hydraulic source and the hydraulic servo means, and the hydraulic switching valve is operated by a pulse motor. It is operated by a hydraulic distribution valve that is driven to achieve speed change operation, so even if the number of stages in the transmission increases, only one hydraulic valve is electrically controlled, and it is driven by a pulse motor. This simplifies the control, making it possible to implement electronic control of automatic transmissions that is compact and highly reliable, including the electronic circuit section.

[Brief explanation of the drawing]

Figure 1 shows a torque converter type with 3 forward speeds and 1 reverse speed.
An example of a stepped automatic transmission is shown, and FIG. 2 shows only the hydraulic circuit related to the present invention of the device shown in FIG. 1. FIG. 3 is a configuration diagram showing an embodiment of the present invention, FIG. 4 is an electric control circuit diagram of the present invention, and FIG. 5 is a shift characteristic diagram showing an example of shift characteristics of a three-speed forward automatic transmission. . 1... Torque converter, 2... Pump impeller, 3... Turbine runner, 5... Turbine shaft,
6...Clutch, 7...Clutch, 11...Planetary gear system, 21...Brake, 22...Brake,
101... Gear stage determination circuit, 104... 2-3 solenoid, 105... 1-2 solenoid, 106
...2-3 switching valve, 107...1-2 switching valve, 122... Hydraulic pump, 124... Hydraulic valve, 125... Manual valve, 206...2
-3 switching valve, 207...1-2 switching valve,
229, 230... Hydraulic drive chamber, 231... Hydraulic distribution valve, 232... Pulse motor, 233... Rotor, 234... Drive coil, 235... Spool, 236... Screw, 237... Port, 2
38, 239... Output port, 242... Gear stage determining circuit, 243... Shift direction determining circuit, 24
4...Drive circuit. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] 1. In an automatic transmission in which a plurality of gear ratios are achieved by selectively operating a plurality of hydraulic servo means, an automatic transmission is provided that is arranged in a hydraulic path between a hydraulic power source and the hydraulic servo means. , a plurality of hydraulic switching valves that selectively operate the hydraulic servo means to perform a gear change operation by switching the hydraulic pressure; and a plurality of hydraulic switching valves that supply or drain hydraulic pressure that drives the hydraulic switching valves, and switch the plurality of hydraulic pressures. A shift control device for an automatic transmission, comprising a single hydraulic distribution valve that operates a valve, and a pulse motor that drives the hydraulic distribution valve based on a gear position determination signal. 2. A gear stage determining circuit that receives input from the rotation sensor and the throttle opening sensor, a shift direction determining circuit to which the output of this gear stage determining circuit is supplied, and a shift direction determining circuit that is controlled by this shift direction determining circuit and drives the pulse motor. A speed change control device for an automatic transmission according to claim 1, further comprising a drive circuit.