JP3099601B2 - Transmission control device for continuously variable transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed change control device for a continuously variable transmission which uses a speed change actuator such as a step motor to control a speed ratio continuously.

[0002]

2. Description of the Related Art Conventionally, as a shift control device of a continuously variable transmission, for example, a shift control device described in Japanese Patent Application Laid-Open No. 63-11436 is known.

[0003] According to the conventional source described above, in the case of a control device that performs shift control using a shift motor, if noise is input to the shift command signal and an error occurs, the error is accumulated, and the shift command signal and the speed of the shift motor are accumulated. The actual rotational position does not correspond, and the shift control accuracy is reduced.

In order to solve this problem, it is determined whether or not the relationship between the signal from the shift reference position sensor and the actual shift command signal is in a preset relationship. A technique is disclosed in which a gear shift command signal is forcibly operated to a mechanical movement limit position on a maximum gear ratio side or a minimum gear ratio side, and a gear shift command signal is calibrated to a state corresponding to this position.

[0005]

However, in the conventional shift control device for a continuously variable transmission, when the sensor failure is determined, the shift actuator is moved to the mechanical movable limit position on the maximum gear ratio side or the minimum gear ratio side. In addition to the gear shift reference position sensor, a sensor or a switch for checking whether the mechanical movement limit position has been reached is required, and the gear shift actuator must be moved to the minimum gear ratio side ( In this case, the drive is driven to the high side to end the initialization, and the normal shift control is started. In this case, however, the high-speed start is started, and the drivability is impaired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide a speed change control device for a continuously variable transmission in which a speed ratio is steplessly controlled using a speed change actuator such as a step motor. In the above, when the reference position sensor is abnormal, the control is started from the state before the initialization of the shift actuator to ensure good startability.

[0007]

In order to achieve the above object, a shift control device for a continuously variable transmission according to the present invention, as shown in the claim correspondence diagram of FIG. a gear ratio command member b which controls the gear ratio by the amount of displacement is driven by the shift actuator a, the speed change ratio command member b are usually variations
And the reference position sensor c detects whether a overstroke region beyond the region of the speed ratio control, the normal shift control
Gear ratio command member b is overstroke before starting
The shift actuator a is driven to be in the region
Position sensor c overshoots beyond normal gear ratio control range
When the trolley area is output, the specified gear ratio
A shift actuator initialization means d for driving the shift actuator a to a position and initializing position information of the shift actuator a ;
The gear ratio command member b is set in the overstroke range by the step d.
Despite the reference position sensor c is O of displacing up
Reference position sensor abnormality determining means e for determining that the reference position sensor c is abnormal when the stroke area is not detected.
When the reference position sensor c is determined to be abnormal by the reference position sensor abnormality determining means e, the position information is initialized.
Drive the shift actuator a to the previous gear ratio position,
A sensor for initializing the position information of the shift actuator a
And a constant-speed actuator initialization means f .

[0008]

When the reference position sensor c is normal, the shift actuator initialization means d starts normal shift control.
Gear ratio command member b is in the overstroke range before
The speed change actuator a is driven in the
Sensor c exceeds the normal speed ratio control range
Output that the vehicle has entered the
Drives the shift actuator a, and the position information of the shift actuator a is initialized. Then, the shift control is performed based on the initialized position information of the shift actuator a.

When the reference position sensor c is abnormal, the reference position sensor abnormality judging means e causes the transmission gear ratio command member b to be overstruck by the transmission actuator initializing means d.
Despite the reference position sensor c of displacing up click region
Does not detect the overstroke region, it is determined that the reference position sensor c is abnormal, and when the reference position sensor c is determined to be abnormal by the reference position sensor abnormality determining means e, the speed change actuator initialization means when the sensor is abnormal to f
Gear ratio to the gear ratio position before the position information is initialized.
Driving the actuator a, the position of the speed change actuator a
The location information is initialized. And this initialized shift
The shift control is performed based on the position information of the actuator a.
Will be

Therefore, when it is determined that the reference position sensor c is abnormal , the speed ratio before the position information is initialized is determined.
The gear ratio control in the previous run.
Initialization to return to the low gear ratio position
When the quasi-position sensor is abnormal, at least high-speed start is prevented, and good startability is ensured.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

First, the configuration will be described.

FIG. 2 shows a power transmission mechanism of a continuously variable transmission to which the transmission control device according to the embodiment of the present invention is applied.

The continuously variable transmission comprises a fluid coupling 12, a forward / reverse switching mechanism 15, a V-belt type continuously variable transmission mechanism 2.
9, a differential device 56, etc., which rotates the output shaft 10a of the engine 10 at a predetermined speed ratio and rotation direction.
6 and 68.

The continuously variable transmission comprises a fluid coupling 12, a rotary shaft 13, a drive shaft 14, a forward / reverse switching mechanism 15, a drive pulley 16 (a fixed cone plate 18, a drive pulley cylinder chamber 20, a movable cone A planetary gear mechanism 17 (comprising a sun gear 19, pinions 21, 23, a pinion carrier 25, a ring gear 27, etc.);
V-belt 24 and driven pulley 26 (consisting of fixed conical plate 30, driven pulley cylinder chamber 32, movable conical plate 34, etc.)
, Driven shaft 28, forward clutch 40, drive gear 4
6, an idler gear 48, a reverse brake 50, an idler shaft 52, a pinion 54, and a final gear 44.
And pinions 58 and 60, side gears 62 and 64,
It is composed of output shafts 66, 68 and the like.

FIG. 3 shows a hydraulic control device for the continuously variable transmission.

This hydraulic control device includes an oil pump 10
1. Line pressure regulating valve 102, manual valve 104, shift control valve 106, regulating pressure switching valve 108, step motor 11
0 (corresponding to shift actuator a), shift operation mechanism 11
2. It has a throttle valve 114, a constant pressure regulating valve 116, an electromagnetic valve 118, a coupling pressure regulating valve 120, a lock-up control valve 122, etc., which are connected to each other as shown in FIG. The clutch 40, the reverse brake 50, the fluid coupling 12, the lock-up oil chamber 12a, the drive pulley cylinder chamber 20, and the driven pulley cylinder chamber 32 are also connected as illustrated.

The reference numerals in FIG. 3 indicate the following members.

Pinion 110a, tank 130, strainer 131, oil passage 132, relief valve 133, valve hole 13
4, ports 134a-e, spool 136, land 13
6a-b, oil passage 138, one-way orifice 138, oil passage 140, oil passage 142, one-way orifice 143, valve hole 1
46, ports 146a-g, spool 148, land 1
48a-e, sleeve 150, spring 152, spring 154, pressing member 158, oil passage 164, oil passage 16
5, orifice 166, orifice 170, valve hole 17
2, ports 172a-c, spool 174, land 17
4a-c, spring 175, oil passage 176, orifice 177, lever 178, oil passage 179, pin 181, rod 182 (corresponding to speed ratio command member b), land 182a
-B, rack 182c, pin 183, pin 185, valve hole 186, ports 186a-d, oil passage 188, oil passage 18
9, oil passage 190, valve hole 192, ports 192a-g, spool 194, lands 194a-e, negative pressure diaphragm 198, orifice 199, orifice 202, orifice 203, valve hole 204, ports 204a-e, spool 206, land 206a-b, spring 208, oil passage 209, filter 211, orifice 216, port 222, solenoid 224, plunger 224a, spring 225, valve hole 230, ports 230a-e, spool 232, land 232a-b, spring 234,
Oil passage 235, orifice 236, valve hole 240, port 2
40a-h, spool 242, lands 242a-e, oil passage 243, oil passage 245, orifice 246, orifice 247, orifice 248, orifice 249, choke type throttle valve 250, relief valve 251, choke type throttle valve 252, pressure holding valve 253, oil passage 254, cooler 25
6. Cooler pressure holding valve 258, orifice 259, limit switch 298 (corresponding to reference position sensor c).

Next, the electronic speed change control device 300 for controlling the operation of the step motor 110 and the solenoid 224 will be described.

As shown in FIG. 4, the electronic speed change control device 300 includes an engine speed sensor 301 and a vehicle speed sensor 30.
2. Electrical signals from the throttle opening sensor 303, shift position switch 304, turbine rotational speed sensor 305, limit switch 298, engine coolant temperature sensor 306, and brake sensor 307 are input.

The limit switch 298 is a switch that is turned on when the rod 182 of the speed change operation mechanism 112 further moves beyond the position where the gear ratio is greatest, that is, in the overstroke range.

The electronic speed change control device 300 has an input interface 311, a CPU (central processing unit) 313, a reference pulse generator 312, a ROM 314, a RAM 315, and an output interface 316, and these are an address path 319 and a data path 320. Has been contacted by

Signals from the engine speed sensor 301, the vehicle speed sensor 302, and the turbine speed sensor 305 are sent to the input interface 311 through waveform shapers 308, 309, and 322, respectively. The signal is AD converter 3
The signal is converted into a digital signal by 10 and sent to the input interface 311.

The reference pulse generator 312 includes a CPU 3
13 to generate a reference pulse. The ROM
314 includes a step motor 110 and a solenoid 22
4 and a data required for the control. The RAM 315 temporarily stores information from each sensor and switch, parameters necessary for control, and the like. An output signal from the electronic shift control device 300 is output to the step motor 110 via the amplifier 317 and is output to the solenoid 224.

Next, the operation will be described.

[Shift control and lock-up control operation] FIG. 5A is a flowchart showing a schematic flow of a shift control operation and a lock-up control operation performed by the electronic shift control device 300. Each step will be described below. .

In step 50, the step motor 110
Is performed according to the flowchart shown in FIG.

In step 51, information necessary for the shift control and the lock-up control is read.

In step 52, shift control is executed in accordance with a predetermined shift control processing program, such as controlling the gear ratio by determining the target turbine speed based on the throttle opening and the vehicle speed.

In step 53, lock-up control is executed according to a predetermined lock-up control processing program.

[Step Motor Initialization Processing Operation] FIG. 5B is a flowchart showing the flow of the initialization processing operation of the step motor 110 performed by the electronic transmission control device 300. Hereinafter, each step will be described (the transmission actuator initialization). Initializing means d, reference position sensor abnormality determining means e, and initial gear shifting actuator when sensor is abnormal
Means f ).

In step 54, the switch signal LOW from the limit switch 298 read in the previous process is
SW is set as the previous LOWSW.

In step 55, the limit switch 29
8 is read.

In step 56, it is determined from the initialization end flag whether or not initialization has not been performed.

In step 57, the motor position information is provisionally set as motor position information = 50. Here, the motor position information is information serving as a reference position of the step motor 110 in performing the shift control. In this case, the motor position information at the maximum speed ratio (low side) is set to 0 (zero), and the minimum speed The motor position information at the ratio (high side) is set to 100, and the motor position information = 50 indicates an intermediate speed ratio position.

In step 58, the limit switch 29
It is determined whether or not the switch signal LOWSW from 8 is on.

In step 59, the target motor position is set to the target motor position = 100, which is the minimum gear ratio position, and the motor position information (=
In order to make 50) coincide, the step motor 110 is driven to the upshift side.

In step 60, the limit switch 29
It is determined whether or not the switch signal LOWSW from 8 has changed from off to on.

In step 61, the motor position information is set to motor position information = 50. In step 62,
The initialization end flag is turned on, and the motor initialization processing ends.

In step 63, it is determined whether the motor position has reached 100.

In step 64, the target motor position is set to the target motor position = 50, which is the intermediate speed ratio position.
In order to make the motor position (= 100) coincide with the target motor position = 50, the stepping motor 11
0 is driven.

In step 65, the initialization end flag is turned on, and the motor initialization processing ends.

In step 66, the target motor position is set to the target motor position = 0, which is the maximum gear ratio position. In order to make the motor position information (= 50) coincide with the target motor position = 0, a step toward the downshift side is performed. Motor 110
Is driven.

At step 67, it is determined whether or not the motor position has become zero.

In step 68, the target motor position is set to a target motor position = 50, which is an intermediate speed ratio position.
In order to make the motor position (= 0) coincide with the target motor position = 50, the step motor 110 is driven to the upshift side.

In step 69, the initialization end flag is turned on, and the motor initialization processing ends.

[Motor Driving Process] FIG. 6 is a flowchart showing the flow of the motor driving process operation of the step motor 110 performed by the electronic shift control device 300. Each step will be described below.

In step 70, a deviation a between the target motor position and the motor position information is calculated.

In step 71, the sign of the deviation a is determined.

In step 72, when the deviation a is positive, a command to drive the step motor 110 rightward by one pulse is output.

In step 73, the motor position information is incremented by one.
Is added.

In step 74, if the deviation a is negative, a command to drive the step motor 110 to the left by one pulse is output.

In step 75, the motor position information becomes -1.
In step 76 in which the difference a is 0, a command to stop the step motor 110 is output when the deviation a is a = 0.

That is, the step motor 110 is driven by calculating the deviation a between the target motor position and the motor position information by a = a
The target motor position and the motor position information are set so that the size corresponding to one pulse is set to one.
, The magnitude of the deviation a becomes the number of pulses output to the step motor 110 as it is.

[When the limit switch 298 is normal] At the start of the motor initialization, since the gear ratio is the gear position at which the gear ratio control in the previous running is completed, that is, the gear ratio at the time of stopping the vehicle, the gear ratio is normally smaller than the intermediate gear ratio. In this state, the low position where the gear ratio is large is the motor position.

At the start of the motor initialization, first, the switch signal LOW from the limit switch 298 is output.
Since the SW is off, the flow proceeds from step 57 to step 58 to step 66 in the flowchart of FIG. 5, and the step motor 110 is set to the downshift side by setting the target motor position = 0 and the motor position information = 50. Driven.

During this driving, the switch signal LOWSW from the limit switch 298 is changed from off to o.
n, step 5 in the flowchart of FIG.
7 → Step 58 → Step 59
The step motor 110 is driven by the upshift side for 50 pulses by setting the target motor position = 100 and the motor position information = 50. In step 61, the motor position information is set to 50 and the initialization processing ends.

That is, the drive is performed as shown in FIG. 7 when it is normal, and when the limit switch 298 is normal, the step motor 110 is driven to the downshift side and the switch signal LOWSW is changed from off to on to be normal. When it is determined that the gear ratio is normal, the position returned to the intermediate gear ratio position that has been driven to the upshift side by 50 pulses with respect to the maximum gear ratio position is the motor position information = 5.
0 is set in the initialization processing.

Therefore, when the step motor 110 is located at the position of the actual intermediate speed ratio, the motor position information is set to 50, and the actual motor position and the motor position information used in the control match. Highly accurate shift control is ensured.

[When limit switch 298 is on abnormally]
Since the switch signal LOWSW from the limit switch 298 is on when the limit switch 298 is on abnormally, the flow proceeds from step 57 to step 58 to step 59 in the flowchart of FIG. Motor position information = 100
With the setting of 50, it is driven to the upshift side.

The switch signal LOW from the limit switch 298 despite the driving is in progress.
In the case of a switch abnormality that does not change while the SW remains on, FIG.
In the flowchart of FIG.
The flow proceeds to step 63. In step 63, it is determined whether or not the motor position is at the motor position = 100, that is, whether or not the motor position has been driven to the upshift side where the motor position becomes 100 by 50 pulses. Is determined, the target motor position is set to target motor position = 50 in step 64, and conversely, the step motor 110 is driven to the downshift side to return to the original position by 50 pulses by this setting, and the position is set to 50. Is set as motor position information = 50 (step 57), and the initialization processing ends.

That is, when the limit switch 298 is on abnormally, the drive is performed as shown in FIG.
An abnormality is determined by driving the step motor 110 to the upshift side. When the abnormality is determined, the position returned to the start position of the initialization processing is set to motor position information = 50.

Therefore, if the motor position is at a position offset from the intermediate speed ratio at the start of the initialization processing, an error in the motor position information corresponding to the offset occurs, but at least the low speed returned to the position before the start of the initialization processing. Driving at the time of starting is ensured by the step starting.

When the limit switch 298 is off, when the limit switch 298 is off, the switch signal LOWSW from the limit switch 298 is turned off.
Therefore, in the flowchart of FIG.
The flow proceeds from step 58 to step 66, and the step motor 110 is driven to the downshift side by setting the target motor position = 0 and the motor position information = 50.

If the drive is normal during the driving, the switch signal LOWS from the limit switch 298 is output.
W changes from off to on, but when there is no switch abnormality, the flow proceeds from step 66 to step 67 in the flowchart of FIG.
In step S7, it is determined whether or not the motor position is motor position = 0, that is, whether or not the motor has been driven by 50 pulses to the downshift side where the motor position is zero.
If it is determined to be es, the target motor position is set to target motor position = 50 in step 68, and by this setting, the step motor 110 is driven to return to the original position by 50 pulses to the upshift side. The position is set as motor position information = 50 (step 57), and the initialization processing ends.

That is, when the limit switch 298 is off, the step motor 110 is driven to the downshift side to determine the abnormality when the limit switch 298 is off, and when the abnormality is determined, the initialization process is started. Position returned to position is motor position information = 5
Set to 0. If the start position is at a position offset to the low side from the intermediate speed ratio, the end of the rod 182 contacts the stationary member and the stroke limit of the rod 182 is reached even if a drive command is output to the motor. By that
The actual motor position matches the motor position information used in the control.

Therefore, o of the limit switch 298
At the time of ff abnormality, the drivability at the time of starting is ensured by starting at the low speed stage by returning to at least the position before the start of the initialization processing.

Next, the effects will be described.

In the transmission control device for a continuously variable transmission that uses the step motor 110 to control the speed ratio in a stepless manner, the step motor 110 is driven based on the signal of the limit switch 298 at the start of the initialization process, and the rod 1 is driven.
When there is no signal change from the limit switch 298 even when the position of the switch 82 is displaced, the limit switch 298 is determined to be abnormal. When the switch is determined to be abnormal, the step motor 110 is returned to a state before the start of the initialization process to return to normal shift control. Since the control is performed to pass the process, when the limit switch 298 is abnormal, the vehicle shifts from the motor initialization process to the speed change control, and the vehicle starts with the low side gear ratio, so that good startability can be secured. .

Although the embodiment has been described with reference to the drawings, the specific configuration is not limited to the embodiment, and even if there are changes and additions without departing from the gist of the invention, the invention is included in the invention. It is.

For example, in the embodiment, as the continuously variable transmission, V
Although an example of application to a belt-type continuously variable transmission has been described, the present invention can also be applied to a trochoid-type continuously variable transmission using a transmission actuator.

In the embodiment, an example in which one limit switch is used as the reference position sensor has been described. However, two limit switches and a stroke sensor may be used.

[0074]

As described above, according to the present invention, a reference position sensor abnormality determination is provided in a shift control device of a continuously variable transmission that continuously controls a speed ratio by using a shift actuator such as a step motor. When the means determines that the reference position sensor is abnormal, the change before the initialization of the position information is performed.
Return to the gear ratio position, that is, the gear ratio control
A sensor that performs initialization to return to the completed low gear ratio position
Since the apparatus is provided with the constant-speed actuator initialization means , at the time of abnormality of the reference position sensor, at least high-speed start is prevented, and an effect of ensuring good startability is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims showing a shift control device for a continuously variable transmission according to the present invention.

FIG. 2 is a diagram illustrating a power transmission mechanism of a continuously variable transmission to which the shift control device of the embodiment is applied.

FIG. 3 is a diagram showing a hydraulic control device of the continuously variable transmission to which the shift control device of the embodiment is applied.

FIG. 4 is a block diagram illustrating a shift control device of the continuously variable transmission according to the embodiment.

FIG. 5 (a) is a flowchart showing a schematic flow of a shift control operation and a lock-up control operation performed by the electronic shift control device, and FIG. 5 (b) is a step motor performed by the electronic shift control device. 5 is a flowchart showing a flow of an initialization processing operation of FIG.

FIG. 6 is a flowchart showing a flow of a motor drive processing operation of a step motor 110 performed by the electronic shift control device.

FIG. 7 is an operation explanatory diagram illustrating the initialization processing of the step motor when the embodiment apparatus is normal, on-abnormal, and off-abnormal.

[Explanation of symbols]

a speed change actuator b speed ratio command member c reference position sensor d speed change actuator initialization means e reference position sensor abnormality determination means f speed change actuator initialization means when sensor is abnormal

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16H 9/00-9/26 B60K 20/00 F16H 59/00-63/48

Claims (1)

(57) [Claims] 1. A speed change actuator that is operated by a speed change command signal, a speed ratio command member that is driven by the speed change actuator and controls a speed ratio by an amount of displacement thereof, and wherein the speed ratio command member is in a normal speed ratio control range. Beyond
The reference position sensor for detecting whether the vehicle is in the overstroke region and the gear ratio command member are turned on before starting the normal gearshift control.
Drive the speed change actuator so that it is in the stroke range.
And the reference position sensor moves beyond the normal gear ratio control range.
When the overstroke area is output,
Drive the speed change actuator to the speed ratio position of
The shift actuator initializing means for initializing the position information of the shift actuator, and the shift actuator initializing means, the reference position sensor detects the overstroke area despite displacing the speed ratio command member to the overstroke area. Otherwise, the reference position sensor abnormality determining means for determining that the reference position sensor is abnormal, and the position information is initialized when the reference position sensor is determined to be abnormal by the reference position sensor abnormality determining means . Before shifting
Drive the speed change actuator to the relative position, and
Gear shift actuator that initializes the
A shift control device for a continuously variable transmission , comprising: a tutor initialization means .