JP2001301494A - Shift controller for mechanical automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shift controller for a mechanical automatic transmission, capable of suppressing shock and clumsiness in a clutch disengaging process. SOLUTION: This shift controller for a mechanical automatic transmission having a friction clutch comprises an actuator 6 for engage/disengage driving the friction clutch according to supplied fluid pressure, a fluid pressure detecting means 15 for detecting the fluid pressure, an actuator drive controlling means 3 for drive-controlling the actuator 6, and a throttle opening controlling means 5 for controlling the opening of a throttle. At the time of starting shift controlling, the throttle opening is controlled by the throttle opening controlling means 5 so as to be decreased. The actuator 6 is driven to a clutch disengaging side by the actuator drive controlling means 3 until the throttle opening achieves a specified opening, and stopped when the fluid pressure obtained from the fluid pressure detecting means 15 becomes a specified pressure with which the friction clutch starts to slip.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for a mechanical automatic transmission in which a manual transmission having a friction clutch is automated.

[0002]

2. Description of the Related Art In recent years, as a transmission for vehicles such as automobiles,
A so-called mechanical automatic transmission has been developed in which a manual transmission including a friction clutch and a parallel two-shaft transmission is automated. In such a mechanical automatic transmission, since a fluid clutch (torque converter) is not interposed in the driving force transmission system from the engine to the driving wheels, the transmission efficiency is higher than the automatic transmission using the torque converter, and the fuel efficiency is improved. Can be achieved. Also, since there is no slip feeling peculiar to the torque converter, drivability is also improved.

[0003]

By the way, in such a mechanical automatic transmission, when performing a shift operation, the clutch is disengaged by being driven by an actuator. The operation is controlled in coordination with the operation of the throttle. In other words, when the clutch is disengaged, the clutch is controlled to a half-clutch state in which the engine is separated from the drive wheels and the load of which is lightened does not blow up, and the throttle is independent of the accelerator pedal opening. Is driven in the closing direction by the actuator (this is called returning the throttle).

[0004] However, if the timing of disengaging the clutch is too fast with respect to the timing of returning the throttle, the engine will blow up or the driving force will decrease sharply, causing a shock. On the other hand, if the timing for disengaging the clutch is too late, there is a problem that a feeling of slack in shifting and a feeling of stall due to engine braking occur.

[0005] Japanese Patent Publication No. 4-64889 discloses that
A technique has been disclosed in which, when a clutch is disengaged without a shift operation, the clutch can be disengaged without generating a shock by disengaging the clutch after the throttle valve opening becomes equal to or less than a predetermined opening. However, this technique is not used for speed change control, and even if applied to speed change control, no clutch disengagement operation is performed until the throttle valve opening becomes equal to or less than a predetermined opening. There is a possibility that a sense of stall or a stall due to engine braking may be caused, and the above problem cannot be solved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and in the process of disengaging the clutch, it is possible to suppress a shock and a feeling of backlash in a mechanical automatic transmission. It is an object to provide a shift control device.

[0007]

Therefore, in the shift control apparatus for a mechanical automatic transmission according to the first aspect of the present invention, at the time of starting shift control, the throttle opening electrically connected to the accelerator pedal of the vehicle. The control means controls the throttle opening to decrease, and until the throttle opening reaches a predetermined opening, the actuator is driven and controlled by the actuator drive control means to the clutch disengagement side, and the fluid pressure detection means When the detected fluid pressure supplied to the actuator reaches a predetermined pressure at which the friction clutch starts to slip, the operation of the actuator is stopped, and the connection / disconnection driving of the friction clutch is stopped.

According to a second aspect of the present invention, in the shift control device for a mechanical automatic transmission according to the first aspect, when the throttle opening is equal to or less than a predetermined opening, the actuator is again controlled by the actuator drive control means. Is driven to the clutch disengagement side, and the friction clutch is disengaged. According to a third aspect of the present invention, the predetermined opening of the throttle is set based on an operation amount of an accelerator pedal.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a mechanical automatic transmission according to an embodiment of the present invention; FIG. FIG. 3 is a schematic diagram illustrating the configuration of the clutch actuator, FIG. 3 is a schematic diagram illustrating the configuration of the shift select actuator, and FIG. 4 is a diagram illustrating an example of a map for estimating the possible engine torque according to the throttle opening. FIG. 5 is a diagram for explaining the operation, and is a time chart showing a change in each state quantity of the vehicle with the passage of time. FIG. 6 is a flowchart for explaining a method of setting the target release stroke gradient. FIG. 7 is a flowchart for explaining a method of setting the throttle return determination value (predetermined opening).

First, a mechanical automatic transmission will be described. This mechanical automatic transmission is different from an automatic transmission having a fluid clutch such as a torque converter, and has a friction clutch and a parallel two-shaft type transmission. In addition, a general manual transmission is provided with an actuator for performing a clutch operation and a shift operation, an electronic control throttle (a so-called drive-by-wire system), etc. in place of a driver, and appropriately controls the operation of these actuators. , The automatic transmission is executed.

Here, a description will be given of a shift control device for a mechanical automatic transmission according to the present embodiment. As shown in FIG. 1, the shift control device includes a controller (A) for an automatic transmission.
/ T-ECU, hereinafter simply referred to as ECU) 30, various sensors 10 to 15, actuators 6 to 8, and a throttle (not shown). , A clutch actuator drive control section (actuator drive control means) 3, a shift select actuator drive control section 4, and a throttle actuator drive control section (throttle opening degree control means) 5.

[0012] Incidentally, the throttle actuator drive control unit 5 is electrically connected to an accelerator pedal (not shown), and a mode for controlling the throttle opening theta _S in accordance with the accelerator opening theta _A, accelerator opening theta _A And a mode for controlling the throttle opening θ _S independently of the above. On the vehicle side, as the sensors described above, an input shaft rotation speed sensor (hereinafter, also referred to as a vehicle speed sensor) 10 that detects the input shaft rotation speed of the transmission main body and functions as a vehicle speed sensor, and an accelerator opening θ _A or an accelerator opening sensor (accelerator opening detection means) that detects the depression amount of the accelerator pedal 11, the engine rotational speed sensor 12 for detecting the engine rotational speed, throttle opening sensor 13 and the clutch for detecting the throttle opening theta _S release stroke and the release pressure of the (fluid pressure, hereinafter referred to as release pressure) release stroke sensor 14 which detect the P _R, the release hydraulic pressure sensor (fluid pressure detecting means) 15 is provided.

Based on the detection information from the vehicle speed sensor 10 and the accelerator opening sensor 11, the shift determining unit 1 determines the shift-up or shift-down timing (shift determination). In response to a shift instruction from the shift determining unit 1, a control signal is set to each of the actuator drive control units 3 to 5.

Further, on the transmission side, as described above,
A clutch actuator (actuator) 6 for connecting and disconnecting the clutch, a shift select actuator 7 for switching a gear position of the transmission body, and a throttle actuator 8 for changing a throttle opening θ _S of an electronically controlled throttle are provided. Have been. The throttle actuator 8 is constituted by, for example, a stepper motor.

The actuator drive control units 3 to
In 5, the operation of the clutch actuator 6, the shift select actuator 7, and the throttle actuator 8 is controlled in accordance with the control signal from the shift execution section 2. Specifically, when a shift is determined by the shift determining unit 1, each operation is executed in the order of a throttle return operation, a clutch disengagement operation, a gear change (switching of a gear position), an engine speed adjustment, and a clutch engagement operation. The shift execution unit 2 controls each of the actuators 6 to 8 at an optimal timing when executing a shift operation.
The control signal is set to each of the drive control units 3 to 5 so that the control signal is operated.

Next, the configurations of the clutch actuator 6 and the shift select actuator 7 will be briefly described with reference to FIGS. 2 and 3, respectively. As shown in FIG. 2, the clutch actuator 6 is provided with a clutch release cylinder 61, and a release fork (not shown) is connected to an end of a push rod (drive shaft) 61b of the clutch release cylinder 61. By controlling the supply / discharge state of the working fluid (in this embodiment, the working oil) to / from the chamber 61a of the clutch release cylinder 61, the push rod 61b of the clutch release cylinder 61 is moved forward and backward to control the engagement state of the clutch. It has become. Here, the clutch is disengaged when hydraulic oil is supplied to the chamber 61a and the push rod 61b of the clutch release cylinder 61 extends rightward in the drawing (that is, when the release stroke increases).

As shown in the figure, between a chamber 61a and an oil tank 62, a hydraulic source (oil pump) 63, a pressure regulating valve (regulator) 64, and a solenoid 6 for supplying hydraulic pressure are provided.
5 and a solenoid 66 for discharging hydraulic pressure are provided. The clutch actuator drive control unit 3 controls the duty of each of these two solenoids (open / close valves) 65 and 66. The on / off control of the two solenoids 65 and 66 changes the state of the hydraulic pressure supply to the chamber 61a, and the connection and disconnection of the clutch is performed.

For example, when the solenoid 65 is turned on (open) and the solenoid 66 is turned off (closed), the chamber 61a
The clutch is disengaged by supplying the operating oil to the clutch. Conversely, the clutch is connected by turning the solenoid 65 off (closed) and turning the solenoid 66 on (open) to drain the hydraulic oil in the chamber 61a to the oil tank 62. As shown in FIG. 2, when both solenoids 65 and 66 are turned off (closed), the state of the clutch is maintained.

As described above, the clutch actuator 6 includes the stroke sensor 14 for detecting the position (release stroke) of the push rod 61b of the clutch release cylinder 61, and the pressure (release) of the working oil supplied to the chamber 61a. Pressure sensor 15 for detecting pressure P _R )
The detection information of these sensors 14 and 15 is fed back to the clutch actuator drive control unit 3.

Next, the shift select actuator 7 will be described with reference to FIG. 3. The shift select actuator 7 includes a shift actuator 71 and a select actuator 72. Among them, the shift actuator 71 is provided such that the operation direction thereof corresponds to the front-rear direction (shift direction) of the shift lever in the manual transmission.
The operation direction is provided so as to correspond to the left-right direction (selection direction) of the shift lever.

These actuators 71, 72
Are configured as three-position hydraulic power cylinders, each of which can take three positions.
By combining the position and the three positions in the select direction, the gear position can be switched by an operation corresponding to the shift pattern of the manual transmission. Here, the configuration of the actuators 71 and 72 will be briefly described by taking the shift actuator 71 as an example.
a, 71b are provided. Pistons 71a, 71b
If the oil pressure is constant, the force acting on the piston 71 increases according to the pressure receiving area. Therefore, by independently applying the oil pressure to the pistons 71a and 71b, the operating position of the actuator 71 is set to It can be switched to three positions as shown below. The actuator 72 has the same configuration as the actuator 71.

As shown in the figure, a hydraulic source (oil pump) 74, a pressure regulating valve (regulator) 75, solenoids 76 to 79, and the like are provided between each of the actuators 71 and 72 and the oil tank 73. Each of the solenoids 76 to 79 is similar to the clutch actuator 6 described above.
By controlling the duty of each piston 71
The state of supply of hydraulic oil to the a and 71b can be appropriately switched. The actuator 7
The operating positions of the gears 1, 72 are switched so that the gear position can be switched.

As described above, in the present shift control device, when a shift is determined by the shift determining unit 1, a throttle return operation, a clutch disengagement operation, a gear change (switching of a shift stage), an engine speed adjustment, and the like are performed. Each operation of the clutch connection operation is executed in this order to perform the shift control. Here, the return operation of the throttle and the clutch disengagement operation, which are features of the shift control device of the present invention, will be further described.

When a shift is determined by the shift determining unit 1, first,
Throttle return operation is performed,
In this throttle return operation, the throttle actuator drive control section 5 sets the throttle return speed (opening change rate in the return direction). The clutch disengagement is started by the clutch actuator drive control unit 3 almost simultaneously with the return operation of the throttle. That is, the operation of the solenoids 65 and 66 is controlled by the clutch actuator drive control unit 3, whereby the clutch release cylinder 61
Hydraulic fluid is supplied to the chamber 61a of the push rod 61b.
Is extended and the clutch disengagement operation is started.

When the clutch is disconnected, the push rod 61
b The so that the speed of extending (= speed of disengaging the clutch) becomes a predetermined target speed (target release stroke gradient) V _R, the clutch release cylinder 61 operates the solenoid 65 by the clutch actuator drive control unit 3 is controlled The supply of hydraulic oil to the engine is adjusted. The target release stroke gradient V _R is obtained by the accelerator opening θ _A obtained by the accelerator opening sensor 11, the throttle opening θ _S obtained by the throttle opening sensor 13, and the release hydraulic pressure sensor 15. is adapted to be set by the shift execution unit 2 was based on the release pressure P _R.

[0026] That is, the throttle opening theta _S is predetermined when the throttle return threshold opening above (predetermined opening) theta _S0 is the release pressure P _R must release pressure P _R0 [release pressure P _R than the pressure If it is higher than a predetermined release pressure (predetermined pressure) at which the engaged clutch starts to slip, the target release stroke gradient V _R is set to the first predetermined speed V ₁ (here, 10 mm / sec) (V _R = V _1), if the release pressure P _R must release pressure P _R0 above, the target release stroke gradient V _R is adapted to be set to zero (V _R = 0).

On the other hand, the throttle returning threshold opening the throttle opening theta _S is at less than (a predetermined opening) theta _S0, the target release stroke gradient V _R is the second predetermined speed V ₂ (in this case 30 mm / sec) It is adapted to be set (V _R = V _2). Thus, when the clutch is disengaged, a shock and a feeling of backlash in the speed change control can be suppressed. That is, when the throttle opening θ _S is equal to or larger than the throttle return determination opening θ _S0 immediately after the start of the shift control (immediately after the start of the throttle return operation), the engine torque is large, and if the clutch is completely disengaged, a shock may occur due to torque fluctuation. There is. Therefore, to increase the release pressure P _R is extended push rod 61b at a predetermined speed V _1,
When the clutch starts slipping becomes release pressure P _R must release pressure P _R0, by setting the target release stroke gradient V _R to zero, the clutch release cylinder 6
1 is stopped. As a result, the release pressure P _R is maintained at the required release pressure P _R0 , the clutch is maintained in a half-clutch state, and the shock is suppressed.

Thereafter, the throttle is returned to the
The throttle is the throttle return judgment opening θ _S0Is closed more than
The engine torque is reduced and the clutch is completely
Since there is no danger of shock even if cutting,
V₁The predetermined speed V greater than_TwoAnd push rod 61b
The clutch is extended to completely disengage
You. And at this point, the clutch is already half-clutched
And immediately disconnect the clutch completely.
(Reducing the time required to completely disengage the clutch)
It's designed to reduce the backlash of gear shifting control
It is.

As described above, the throttle opening θ
_SIs the throttle return determination opening θ_S0When the above,
Target release stroke gradient V_RIs the predetermined speed V₁Set to
On the other hand, the throttle opening θ_SBut throttle return judgment
Opening θ_S0Smaller than the target release stroke
Gradient V_RIs the predetermined speed V_TwoIs set to the predetermined speed V
₁Puts the clutch in a half-clutch state while returning the throttle.
If possible, and if too large, overshoot
10 mm / sec.
, While the throttle opening θ_SReturns throttle
Judgment opening θ_S0If it is smaller than
In order to immediately disengage the clutch, _TwoHako
Here, the predetermined speed V₁30mm / sec larger than
Is set.

Also, the above-described throttle return determination opening degree θ
_S0 is adapted to be set according to the accelerator opening theta _A, is adapted to be set larger as the accelerator opening theta _A is large. Specifically, if the accelerator opening θ _A is equal to or smaller than a predetermined opening θ _A0 (for example, 50%), the throttle return determination opening θ _S0 is set to one fifth of the accelerator opening θ _A (θ _S0 = Θ _A / 5) On the other hand, if the accelerator opening θ _A is larger than the predetermined opening θ _A0 , the throttle return determination opening θ
_S0 is adapted to be set to one third of the accelerator opening _{θ A (θ S0 = θ A} / 3).

By setting the throttle return determination opening degree θ _S0 in this manner, it is possible to suppress engine idle, deceleration shock, stall feeling, and the like. That is,
As described above, the disconnection of the clutch is performed after the throttle opening θ _S becomes smaller than the throttle return determination opening θ _S0 by the throttle returning operation. Therefore, the greater the throttle return determination opening θ _S0 is set, the earlier the timing at which the throttle opening θ _S becomes smaller than the throttle return determination opening θ _S0 , and the subsequent shifts such as complete clutch disengagement. The control is quickly performed.

Therefore, when the accelerator opening θ _A is equal to or smaller than the predetermined opening θ _A0 and quick acceleration is not requested by the driver, the throttle return determination opening θ _S0 is set to a relatively small value and the clutch disengagement is compared. Since it is performed very late, it is possible to prevent the clutch from being disengaged too early and causing the engine to idle or to cause a deceleration shock. On the other hand, when the accelerator opening θ _A is larger than the predetermined opening θ _A0 and a quick acceleration is requested by the driver, the acceleration is prioritized, and the throttle return determination opening θ _S0 is set relatively large and the clutch is opened. Since the disconnection is performed relatively early, it is possible to suppress the occurrence of a stall feeling due to the engine brake due to a delay in disconnection of the clutch against the driver's intention.

Here, the required release pressure _PR0 will be described. The required release pressure P _R0, a predetermined release pressure to start slipping clutch release pressure P _R as described above was the connected state is higher than the pressure (predetermined pressure), the release pressure P _R must release pressure At the time of _PR0 , the clutch is in a completely directly connected state, and the engine output shaft and the transmission input shaft connected by this clutch rotate integrally.

[0034] Stated differently, the required release pressure P _R0, and [generating engine torque T _E that it is input to the transmission input shaft via the clutch occurs the engine torque T _E that is input from the engine output shaft, Torque (clutch transmission torque) T transmitted to the transmission input shaft by the clutch
And a _C equal] As a required release pressure P _R to press the clutch with sufficient pressure, the release pressure P _R
Is smaller than the required release pressure P _{R0, the} force for pressing the clutch (clutch pressing additional load) F _C becomes lower than the pressing force required for completely directly coupling the clutch, and the clutch starts to slip as described above. is there.

[0035] Such need release pressure P _R0 varies in response to the occurrence engine torque T _E. Hereinafter, a method of calculating the required release pressure _PR0 will be described. The clutch transmission torque T _C is the clutch pressing load F _C and the outer diameter D of the annular friction material (fading) attached to the clutch disk.
_OUT, using an inner diameter D _IN and the friction coefficient mu, can be calculated by the right-hand side of the formula (1), therefore, generated engine torque T _E and the clutch transmission torque T _C and satisfies the following relation when the equal (1) To establish.

T_E= 2 × μ × F_C× (D_OUT ^Three-D_IN ^Three) / (D_OUT ^Two-D_IN ^Two) / 3 (1) Also, the clutch pressing additional load F_CAnd release pressure P_RRelationship with
Is pressing set weight F₀, Chamber 6 of release cylinder 61
Cross section A of 1a_R, Diaphragm lever ratio R_DAnd Lerry
Z fork lever ratio R_RAnd expressed by the following equation (2).
It is. F_C= F₀−P_R× A_R× R_D× R_R ... (2) Pressing set weight F₀What is release fork lever
No input to the diaphragm spring
In this case, the clutch spring is
The force with which the disc is pressed (connected)
Release pressure P _RAnd push rod 61b
To deform the diaphragm spring
More clutch pushing load F_CDisengage clutch by reducing
It can be driven to the side.

In the above equations (1) and (2), the pressing set
Weight F₀Sectional area of the chamber 61a of the release cylinder 61
A_R, Diaphragm lever ratio R_D, Release folk lever
-Ratio R _R, Fading outer diameter D_OUT, Inner diameter D_INAnd friction
The coefficient μ is determined by the structure of the clutch.
Therefore, it is stored as a constant value in the ECU 30 in advance,
Also, the generated engine torque T_EIs a slot
Throttle opening θ obtained by the throttle opening sensor 13_SOr
Can be uniquely determined.

[0038] Thus, it is possible to calculate from the above equation (1), the clutch pressing weighted F _C required to equally generated engine torque T _E and the clutch transmission torque T _C according to the throttle opening theta _S . Then, by substituting this clutch pressing weighting F _C in the above equation (2), from the relationship shown in the equation (2), generating the engine torque T _E and the release pressure necessary to equal the clutch transmission torque T _C P _R , that is, the required release pressure P _R0 can be calculated.

[0039] Here, the generation engine torque T _E in the formula (1), the torque of theoretical may occur in the throttle opening theta _S at that time (generable engine torque), a throttle opening In accordance with θ _S , the estimation is performed in accordance with a map as shown in FIG. The actual generated engine torque (actual engine torque) includes friction loss, etc.
It becomes smaller than the possible engine torque. Therefore, the possible engine torque is generated by the generated engine torque _TE.
From the above equations (1) and (2), the required release pressure P
_R0 by calculating the (release pressure P _R), as is apparent from these equations, must release pressure P _R0 (release pressure P _R) is to be smaller set than the actual required release pressure P _R0 It has become.

[0040] As described above, when the clutch disengagement, should release the release pressure P _R for the shock when the throttle opening theta _S is fully disengages the clutch when the throttle returning threshold opening theta _S0 or is likely to occur by but is set to pressure P _R0 is set to be a half-clutch state, setting the required release pressure P _R0 rather small with generable engine torque as a generator the engine torque T _E, as described above, The clutch is controlled to the connected side so that the shock can be reliably prevented.

If the actual engine torque can be accurately calculated, the required release pressure _PR0 is calculated from the above equations (1) and (2) using the actual engine torque instead of the possible engine torque. You may do it. Since the shift control device for a mechanical automatic transmission according to one embodiment of the present invention is configured as described above, the shift control is performed stepwise in five phases as shown in FIG. 5, for example. Is done. That is, in phase 0 (shift control standby state), when a shift instruction is output from the shift determination unit 1 to the shift execution unit 2, the process proceeds to phase 1.

[0042] In phase 1, the throttle begins to be returned, the control signals from the shift execution unit 2 to the clutch actuator drive control unit 3 is outputted, by the clutch actuator drive control unit 3, a target release stroke gradient V _R is given Solenoid 65 to reach speed
The operation of (see FIG. 2) is controlled. In this case, the target release stroke gradient V _R is set, for example, as shown in the flowchart of FIG. That is, first, step A
10, the release pressure P _R obtained in the throttle opening theta _S and the release hydraulic pressure sensor 15 obtained by the throttle opening sensor 13 is read into the clutch actuator drive control unit 3, the process proceeds to step A20, as described above , the generable engine torque T _E in accordance with the throttle opening theta _S is determined according to the map shown in FIG. 4, in accordance with the generative engine torque T _E and thus the throttle opening theta _S,
The required release pressure _PR0 is calculated from the above equations (1) and (2). Then, the process proceeds to Step A30, where the throttle return determination opening degree θ _S0 is calculated.

The calculation of the throttle return determination opening θ _S0 is performed, for example, as shown in the flowchart of FIG.
First, in step B10, the accelerator opening θ _A is read from the accelerator opening sensor 11 into the clutch actuator drive control unit 3, and in step B20, the accelerator opening θ _A
Is _smaller than or equal to the predetermined opening θ _A0 , and if the accelerator opening θ _A is equal to or _smaller than the predetermined opening θ _A0 , the process proceeds to step B40 and the throttle return determination opening θ _S0 is the accelerator opening θ _A
(Θ _S0 = θ _A / 5). On the other hand, if the accelerator opening θ _A is larger than the predetermined opening θ _A0 , the throttle return determination opening θ _S0 becomes the accelerator opening θ _A. It is set to 1/3 (θ _S0 = θ _A / 3).

When the throttle return determination opening θ _S0 is calculated in this manner, step A in FIG.
Proceeding to 40, it is determined whether or not the throttle opening θ _S is smaller than the throttle return determination opening θ _S0 , and the throttle opening θ _S becomes the throttle return determination opening immediately after the start of the throttle return operation as in phase 1. If θ _S0 or more, the process proceeds to step A50.

[0045] is determined or smaller or not than step A50 the release pressure P _R must release pressure P _R0 is, if the small clutch connected state than the release pressure P _R must release pressure P _R0, target release stroke gradient V _R is set to a predetermined speed V _1. Accordingly, in order to extend the clutch release fork at the predetermined speed V ₁ and shift the state of the clutch to the disengagement side, the solenoid 65 is controlled by the clutch actuator drive control unit 3, and the hydraulic oil is supplied to the clutch release cylinder 61. . Thus, as shown in FIG. 5, in phase 1, increased as shown release pressure P _R is in broken lines, the release stroke is extended as shown by the solid line at a predetermined speed V _1, the clutch coupling degree (clutch coupling degree Is described later) is 0
From 1 to 1.

Meanwhile, in step A50 of FIG. 6, if the release pressure P _R must release pressure P _R0 above, Step A
Proceed to 60, a target release stroke gradient V _R is set to zero. Thus, it is supplied stops in the hydraulic fluid to the clutch release cylinder 61, as shown in FIG. 5, the holding in Phase 1, with the release pressure P _R have the release pressure P _R0 until once required release pressure P _R0 rises is, the clutch is release stroke which has been stretched at a predetermined speed V ₁ is stopped until it is held in a half-clutch state. For this reason, as shown in FIG. 5, the rotation speed of the transmission input shaft (hereinafter referred to as T / M input shaft rotation speed) _NT is lower than the rotation speed of the output shaft of the engine (that is, the engine rotation speed) Ne. To go.

In step A40 of FIG.
Opening θ_SIs the throttle return determination opening θ_S0Smaller than
If so, proceed to step A80 to set the target release stroke
Distribution V _RIs the predetermined speed V_TwoIs set to As a result, FIG.
As shown, in phase 1, throttle return operation
The throttle return opening θ_S0Closed until
In other words, the phase shifts from phase 1 to phase 2 and the clutch
Supply of hydraulic oil to the release cylinder 61 is resumed,
As a result, as shown by a broken line in FIG._RBut
Ascends and the release stroke reaches the predetermined speed V_TwoTo extend
And the clutch which was held in the half clutch state until then
Is disengaged (the clutch engagement is raised above 3
).

Here, the degree of clutch engagement will be described. The degree of clutch engagement is a measure of the engaged / disengaged state of the clutch, and is uniquely determined according to the release stroke. The degree of clutch engagement is set to five levels. A degree of clutch engagement of 0 (zero) indicates that the clutch is completely connected, and a degree of clutch engagement of 1 indicates that the clutch is at the connection boundary (that is, when the degree of clutch engagement is higher than this). A clutch engagement degree of 3 indicates a clutch disengagement boundary (i.e., a state where the disengaged clutch starts sliding contact when the clutch engagement degree becomes smaller than this). ), The clutch engagement degree 4 indicates a state in which the clutch is completely disengaged, and the clutch engagement degree 2 indicates an intermediate state between the clutch engagement degrees 1 and 3.

In the present embodiment, the required release pressure P _R0 calculated according to the throttle opening θ _S as described above is used instead of the clutch engagement degree uniquely determined according to the release stroke. , The half-clutch state of the clutch is accurately determined. Then, as shown in FIG. 5, based on the detection information of the release stroke sensor 14, when it is detected that the clutch engagement degree is a predetermined engagement degree (here, engagement degree 3) and the clutch has reached the disconnection point, Move to phase 3.

In phase 3, the release stroke is extended and the clutch is completely disengaged (the degree of clutch engagement becomes 4). Further, a control signal is output from the shift execution unit 2 to the shift select actuator drive control unit 4, and the shift select actuator 7 is controlled by the shift select actuator drive control unit 4 to perform a gear change (shift up in this case). Accordingly, the T / M input shaft rotation speed _NT is greatly reduced. When a shift position sensor (not shown) detects that the shift position of the gear position is at a predetermined position, the process proceeds to phase 4.

In the phase 4, in order to suppress a shock at the time of a clutch connection performed thereafter, the engine speed Ne is substantially matched with the T / M input shaft speed NT so that the engine speed Ne is substantially equal to the T / M input shaft speed _NT .
The throttle opening is controlled by the throttle actuator drive controller 5 via the throttle actuator 8. Then, when conditions such as the difference between the engine rotation speed Ne and the T / M input shaft rotation speed _NT become equal to or less than a predetermined value are satisfied, the process proceeds to phase 5.

In phase 5, the release pressure is reduced by the control of the clutch actuator drive control unit 3 to reduce the release stroke and the degree of clutch engagement, whereby the clutch is engaged and the shift control ends. Incidentally, by decreasing the slope of the release stroke (change rate) in the clutch connection boundaries release pressure P _R is near required release pressure P _R0 are suppressed shift shock. Immediately before the clutch is completely engaged, the throttle opening θ _S becomes
To match the accelerator opening theta _A, operation of the throttle actuator 8 is controlled by a throttle actuator drive control unit 5.

Therefore, according to the present shift control device, the following advantages can be obtained. That is, in the clutch disengagement operation during the shift control, when the throttle opening theta _S is in throttle returning threshold opening theta _S0 or more, there is a fear that when cutting the clutch deceleration shock due to the torque fluctuation occurs, the release pressure P _R Is increased to the required release pressure P _R0 and held in the half-clutch state, so that there is an advantage that the deceleration shock due to torque fluctuation can be suppressed.

Thereafter, the throttle opening θ _S is changed to the throttle returning determination opening θ _S0 by a throttle returning operation.
Becomes below can be immediately cut by raising the release pressure P _R to (by extending the release stroke) clutch from the half clutch state. Therefore, since the clutch is already in the half-clutch state when the clutch is disengaged, there is an advantage that the time required for disengaging the clutch can be shortened and the feeling of backlash can be suppressed.

As described above, the throttle opening θ
_SRequired release pressure P according to_R0Can be calculated accurately
Release during throttle return operation.
Pressure P _RRequired release pressure P_R0Control to become
This allows the clutch to be used without letting the engine
From the point
To reduce the time required to disengage the clutch
There is an advantage that can be.

Further, the throttle return determination opening θ _S0 is set to be larger as the accelerator opening θ _A is larger, so that the clutch is disconnected at an appropriate timing according to the driver's intention, and the engine is idled. There is an advantage that the feeling of stall due to deceleration shock and engine braking can be suppressed. That is, when the accelerator opening θ _A is equal to or less than the predetermined opening θ _A0 and quick acceleration is not required, the throttle return determination opening θ _S0 is set relatively small, and the clutch disengagement is performed relatively late. In the case where the clutch is disengaged too early to prevent the engine from idling or deceleration shock, on the other hand, when the accelerator opening θ _A is larger than the predetermined opening θ _{A0 and} quick acceleration is required. In this case, the acceleration is prioritized, the throttle return determination opening degree θ _S0 is set relatively large, and the clutch disengagement is performed relatively early, so that the clutch disengagement is delayed and a stall feeling due to engine braking may occur Can be suppressed.

The shift control device for a mechanical automatic transmission according to the present invention is not limited to the above-described embodiment, but can be variously modified without departing from the spirit of the invention. For example, in the above-described embodiment, as shown in the flowchart of FIG. 7, the method of setting the throttle return determination opening θ _S0 is switched depending on whether the accelerator opening θ _A is larger than the predetermined opening θ _A. and which is, as long as the throttle returning threshold opening theta _S0 greater the accelerator opening theta _A is set larger, the accelerator opening theta _A by formula
_May be configured to set the throttle return determination opening degree θ _S0 according to.

[0058]

As described above in detail, according to the shift control device for a mechanical automatic transmission according to the first aspect of the present invention, the throttle opening may cause a deceleration shock even if the friction clutch is disconnected. Until the opening is reduced to a predetermined opening, the friction clutch is driven by the actuator drive control means to the disconnection side via the actuator, and when the fluid pressure supplied to the actuator reaches the predetermined pressure, the operation of the actuator is stopped. The friction clutch is maintained in the slip state (semi-friction clutch state).

Thus, in the process of disconnecting the friction clutch, it is possible to suppress a shock, and since the friction clutch is disconnected from the half-clutch state, the time required to disconnect the friction clutch can be reduced. There is an advantage that it is possible to suppress the feeling of backlash. According to the shift control device for a mechanical automatic transmission according to the second aspect of the present invention, after the throttle opening becomes equal to or less than the predetermined opening and there is no possibility that a shock will occur even if the friction clutch is disengaged, Again, the actuator drive control means drives the actuator to the clutch disengagement side and the friction clutch is completely disengaged. Therefore, the advantage that the time required to disengage the friction clutch can be reduced and the feeling of rattling can be suppressed. is there.

In the shift control device for a mechanical automatic transmission according to the third aspect of the present invention, the predetermined opening of the throttle is set based on the operation amount of the accelerator pedal. In addition, the friction clutch is disengaged at an appropriate timing, so that there is an advantage that the feeling of stall due to the engine idle, deceleration shock and engine brake can be suppressed.

[Brief description of the drawings]

FIG. 1 is a control block diagram showing a functional configuration of a shift control device for a mechanical automatic transmission as one embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a clutch actuator according to a shift control device for a mechanical automatic transmission as one embodiment of the present invention.

FIG. 3 is a schematic diagram showing a configuration of a shift select actuator according to a shift control device for a mechanical automatic transmission as one embodiment of the present invention.

FIG. 4 is a diagram illustrating an example of a map for estimating a possible engine torque applied to a shift control device of a mechanical automatic transmission according to an embodiment of the present invention in accordance with a throttle opening.

FIG. 5 is a diagram for explaining the operation of the shift control device of the mechanical automatic transmission as one embodiment of the present invention, and is a time chart showing changes in each state amount of the vehicle with time. is there.

FIG. 6 is a flowchart for explaining a method of setting a target release stroke gradient according to the shift control device of the mechanical automatic transmission as one embodiment of the present invention.

FIG. 7 is a flowchart illustrating a method of setting a throttle return determination value (predetermined opening) according to the shift control device for a mechanical automatic transmission as one embodiment of the present invention.

[Explanation of symbols]

3 Clutch actuator drive control section (actuator drive control means) 5 Throttle actuator drive control section (throttle opening degree control means) 6 Clutch actuator (actuator) 15 Release hydraulic pressure sensor (fluid pressure detection means)

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) EB01 EB03 EC04 FA04 FA08 FA12 FA14 FB03 3G301 JA03 JA04 JA14 KA11 KB10 LA03 NA03 NA07 ND05 ND41 NE03 NE04 NE08 NE09 NE18 NE20 PA12A PE01A PE01Z PF03A PF03Z PF06A PF06Z PF08A PF08Z01 GB01 GB01 GB01 GB01

Claims (3)

[Claims] 1. A shift control device for a mechanical automatic transmission having a friction clutch, comprising: an actuator that operates in accordance with a supplied fluid pressure to disconnect and drive the friction clutch; and a fluid pressure supplied to the actuator. Pressure control means for detecting the pressure of the vehicle, actuator drive control means for controlling the drive of the actuator, and throttle opening control means for controlling the opening of a throttle electrically connected to the accelerator pedal of the vehicle. At the start, while the throttle opening control means is controlled so as to decrease the throttle opening,
Until the throttle opening reaches a predetermined opening, the actuator is driven and controlled by the actuator driving control means to the clutch disengagement side, and the fluid pressure obtained from the fluid pressure detecting means is a predetermined pressure at which the friction clutch starts to slip. A shift control device for a mechanical automatic transmission, wherein the operation of the actuator is stopped when the pressure is increased. 2. When the throttle opening becomes equal to or less than the predetermined opening, the actuator is again controlled to be disengaged by the actuator drive control means, and the clutch is disengaged. Item 3. A shift control device for a mechanical automatic transmission according to Item 1. 3. The shift control device for a mechanical automatic transmission according to claim 1, wherein the predetermined opening of the throttle is set based on an operation amount of the accelerator pedal.