JPH10109572A - Controller for vehicle power unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce blow-up of an engine generated in changing it from a lock-up state to a converter state by synchronizing the start of an engine output reduction with the start of the release of the lock-up, in releasing the lock-up in changing the speed by pushing down an accelerator pedal. SOLUTION: When a driver pushes down an accelerator so as to perform manual upshift in traveling under a lock-up state, the driver set a shift lever 9 to the upshift position once so that the manual upshift instruction is emitted to a controller 200 and the controller 200 turns off the lock-up solenoid 8 so as to release the lock-up. Then, synchronized with this lock-up release signal, the engine 1 starts an ignition time retarding control (retard control) for retarding the ignition time of the engine by an engine controller 100. This constitution can reduce the blow-up of the input element side rotation speed during releasing the lock-up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention includes a fluid transmission device having a lock-up mechanism for transmitting power from an engine to a stepped automatic transmission. The present invention relates to a control device for a vehicle power unit that releases lockup of a transmission.

[0002]

2. Description of the Related Art A power unit for a vehicle is generally provided with a fluid transmission device in order to require a torque increasing function and a torque fluctuation absorbing function. However, since the fluid transmission device generates a slip between input and output elements, a power transmission device is required. Fluctuation in transmission efficiency is inevitable.

[0003] Therefore, in today's fluid transmission device, when shifting to an operating state that does not require a torque increasing function or a torque fluctuation absorbing function, the converter state is changed from a converter state in which the input and output elements are not slip limited to a mechanical state between the input and output elements. In many cases, a lockup mechanism capable of switching to a lockup state directly connected is provided.

In the lock-up control of such a fluid transmission, when a lock-up region is individually defined for each of a plurality of shift speeds, a shift occurs while the lock-up state is maintained. At the time of the shift, since the torque fluctuation absorbing function of the fluid transmission cannot be used and a large shift shock occurs, it is necessary to temporarily unlock the fluid transmission during the shift even in the lock-up region. General.

[0005]

However, for example, at the time of gear shifting involving depression of the accelerator pedal, if the lock-up is to be released for gear shifting, the engine output is high, and the engine output associated with the lock-up release is increased. A run-up may occur, giving the driver an uncomfortable feeling.

A stepped automatic transmission in which a power transmission device transmits power from an engine is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-2.
As described in Japanese Patent Application Laid-Open No. 7220, while a manual shift range other than the conventional shift range is selected, a manual shift stage corresponding to a manual shift command by a driver can be selected. The above-mentioned problem is remarkable because the stepped automatic transmission having the configuration can be in a lockup state even at a low vehicle speed and a high engine output.

[0007] The present invention has been made in view of the above facts.
An object of the present invention is to solve the above-described problem by reducing engine wake-up that occurs when a converter state in which the direct connection is released from a lock-up state in which the input / output element of the fluid transmission device is directly connected is released. is there.

[0008]

According to the present invention, there is provided a control device for a vehicle power unit, comprising: a fluid having a lock-up mechanism for transmitting power from an engine to a stepped automatic transmission; In a vehicle having a transmission, in a lock-up state in which the input / output elements of the fluid transmission are directly connected to each other, the speed of the fluid transmission is set to a converter state in which the direct connection between the input / output elements is released. When performing lock-up release at the time of gear shifting accompanied by depression of an accelerator pedal, the start of engine output reduction for preventing the engine from rising due to the lock-up release is synchronized with the start of the lock-up release. It is characterized by having comprised.

According to a second aspect of the present invention, there is provided a vehicle power unit control device according to the first aspect,
The stepped automatic transmission is configured to enable selection of a manual gear position corresponding to a manual gearshift command by a driver during selection of a manual gearshift range. The shift is a shift corresponding to a manual shift command when a range is selected.

Further, according to claim 3, which is the present invention,
A control device for a power unit for a vehicle includes:
, Characterized in that the engine output reduction is terminated during a shift accompanied by depression of the accelerator pedal.

[0011] In addition, according to claim 4 of the present invention,
The control device for a power unit for a vehicle according to any one of claims 1 to 3, wherein a start time of a shift accompanied by depression of the accelerator pedal is delayed from a start time of lock-up release. Is what you do.

[0012]

According to a first aspect of the present invention, in the control device for a vehicle power unit, when the lock-up is released at the time of gear shifting accompanied by the depression of an accelerator pedal, the engine blows up due to the release of the lock-up. The engine output is reduced in order to prevent the occurrence of the lock-up, and the start of the engine output reduction is synchronized with the start of the lock-up release. Can be prevented from running up when the engine is released, and the driver does not feel uncomfortable.

According to a second aspect of the present invention, there is provided a vehicle power unit control device according to the first aspect.
Since the shift accompanied by the depression of the accelerator pedal is a shift when a manual shift range that enables a manual shift corresponding to a manual shift command from the driver is selected, the following operational effects are obtained. In the shift in the manual shift range, lockup can be performed even in a region where the vehicle speed is low and the engine output is high. Therefore, especially when the lockup is released, the engine speed is large. Therefore, in shifting with the manual shifting range,
The function and effect of claim 1 become more remarkable.

Further, according to claim 3 of the present invention,
A control device for a power unit for a vehicle includes:
In the above, since the engine output reduction is terminated during a shift accompanied by depression of the accelerator pedal, a shock that occurs when the engine output reduction ends and the engine output rises again can be absorbed as a shift shock, Does not give the driver a sense of incompatibility.

[0015] In addition, according to claim 4 of the present invention,
The control device for a vehicle power unit according to any one of claims 1 to 3, wherein a start time of a shift accompanied by depression of the accelerator pedal is delayed from a start time of lock-up release. The effect is obtained. During the lock-up release operation, a considerable amount of sliding occurs between the lock-up clutches due to slippage. In addition, when a gear shift is performed during the lock-up releasing operation, a torque fluctuation due to the gear shift is transmitted from the output element side of the fluid transmission, and the friction between the lock-up clutches may increase. Therefore, if the shift start time is delayed from the lock-up release start time, during the lock-up release operation, the torque fluctuation due to the shift is not transmitted to the output element side of the fluid transmission. Therefore, a large rub caused by shifting during the lock-up release operation is prevented,
By protecting the facing of the lock-up clutch, the durability of the lock-up mechanism can be improved.

[0016]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows a control device for a vehicle power unit according to the present invention, wherein 1 is an engine controllable by an engine controller 100, and 2 is a stepped automatic transmission. The stepped automatic transmission 2
Basically, “R” issued by the applicant of the present application in March 1987
E4R01A Automatic Transmission Maintenance Manual "(A261C07)
It is assumed that the power of the engine 1 is input via a torque converter 3 which is a fluid transmission device, the input rotation is shifted at a gear ratio corresponding to a selected shift speed, and transmitted to the output shaft 4.

At this time, the stepped automatic transmission 2 can select the first to fourth speeds by controlling the first shift solenoid 6 and the second shift solenoid 7 in the control valve unit 5 to be ON and OFF. Further, the torque converter 3 controls the lock-up solenoid 8 in the unit 5 to turn on and off, thereby changing the lock-up state in which the input / output elements are directly connected to the converter state in which the direct connection between the input / output elements is released. can do.

These ON and OFF signals are controlled by a controller 200. The controller 200 receives a position signal from a shift lever 9 operated by a driver and detects a throttle opening TVO of the engine 1. A signal from a throttle opening sensor 10 and a signal from a vehicle speed sensor 11 for detecting a vehicle speed VSP are input.

The shift lever 9 has a parking (P) range position, a reverse running (R) range position, a neutral (N) range position, an automatic forward shift (D) range position, and an engine brake (L) range position. Are in a range having an automatic shift range arranged on a straight line and a manual shift range (M) offset from the shift range. In the manual shift range (M), the shift lever 9 is supported between the upshift (+) position and the downshift (-) position in a self-returning manner, and the driver shifts upshifting to one step higher speed. The shift lever 9 is set to the upshift (+) position each time the user desires, and the shift lever 9 is set to the downshift (-) position each time a downshift to one step lower speed is desired. Output.

In the stepped automatic transmission 2, the controller 2 determines whether the shift lever 9 is in the manual shift range (M) or not.
00, different shift control is performed. When it is not the manual shift range (M), an automatic shift based on the automatic shift range is performed, and this automatic shift is performed in the P range, the R range, the N range, the D range, and the L range in substantially the same manner as in the above literature. Shift control and lock-up control are performed. However, the L range is 1 in the literature.
It is described as a range.

Here, the shift control in the D range will be described as a representative example of the automatic shift based on the automatic shift range. The controller 200 shows a shift map illustrated in FIG. 4 (a solid line is an upshift shift line, and a broken line is a downshift shift line). The vehicle speed VSP and the throttle opening T
A suitable gear is searched from VO. Next, it is determined whether or not the currently selected shift speed matches the preferred shift speed,
If the speeds do not match, the shift solenoids 6, 7 are turned on and off so that the shift to the preferred gear stage is performed. If the speeds match, the shift solenoids 6, 7 are turned on and off as they are. Automatically executes the shift control according to the D range shift map.

On the other hand, if it is determined that the manual shift range (M) has been selected, the controller 200 determines each of the shift maps M _{1 to} M ₄ illustrated in FIG. 5 (solid lines are upshift shift lines, broken lines are downshift shift lines). Is shown))
A suitable shift speed is searched from the manual shift command of the shift lever 9. However, each on these shift map M ₁ ~M _4, showing the area of the available gear position by manual shift command.

At the beginning of the shift from the D range to the M range, the ON / OFF of the shift solenoids 6, 7 is not changed so as to maintain the gear immediately before the shift, and the driver moves the shift lever 9 to the M range. After that, every time a manual upshift command is issued by setting the gear to the upshift (+) position, a manual upshift to one step higher speed is performed, and conversely, the driver downshifts the shift lever 9 (−). ) When the manual downshift command is issued at the position, the shift solenoids 6 and 7 are set to the O position so that the manual downshift to the one-step lower speed side is performed.
N and OFF are to be switched.

The controller 200 performs lock-up control in the manual shift (M) range based on a lock-up area line L shown by a dashed line in FIG.
That is, when the second speed selected, as shown in the map M _2, the right side area of the lock-up region line L2, that is, the vehicle speed V
SP is at at the lock-up vehicle speed V2 (= 34) or more, the torque converter 3 lockup state by turning ON the lock-up solenoid 8, third speed selected, as shown in the map M _3, the lock-up region line In the right region of L3, that is, when the vehicle speed VSP is the lockup vehicle speed V3
(= 52) or more, the lock-up solenoid 8
The torque converter 3 lockup state with ON, and the fourth speed selected, as shown in the map M _4, in the right region of the lock-up region line L4, that is, the vehicle speed VS
When P is higher than lockup vehicle speed V4 (= 75),
The lock-up solenoid 8 is turned on to bring the torque converter 3 into a lock-up state.

During manual 1st speed selection, the map M
_As shown in FIG. ₁ , the torque converter 3 is not locked up, and the lock-up vehicle speeds V2 to V4 are:
The lower the lock-up vehicle speed in the lower gear, the lower the speed so that the lock-up is started at the same engine speed when the manual second to fourth speed is selected.

According to the setting of the lock-up vehicle speeds V2 to V4, even if the vehicle speed is lower than the high lock-up vehicle speed V4, if the manual speed is lower than the lock-up vehicle speed V3, the manual speed becomes lower. High-speed lock-up is possible, and a large engine brake can be generated between the gear position and the lock-up state of the torque converter 3. In the case of manual second speed, the vehicle speed is reduced until the vehicle speed becomes lower than the lock-up vehicle speed V2. In the meantime, lockup at manual second speed is possible, and a large engine brake can be generated between the gear position and the lockup state of the torque converter 3, and an area where the engine brake can be generated can be expanded. Becomes

However, the lock-up vehicle speed V2
When V4 is set, the range in which lockup is possible is expanded to a region where the vehicle speed is low and the throttle opening is high, so that the shift is accompanied by depression of the accelerator pedal. In the manual upshift when the lock-up is performed in the opening range, the engine is greatly blown up as the lock-up is released. This blow-up gives the driver an uncomfortable feeling.

Accordingly, the control device for a vehicle power unit according to the present invention, when performing lock-up release at the time of gear shifting accompanied by depression of an accelerator pedal, controls the engine output in order to prevent the engine from running up due to the lock-up release. The start of engine output reduction is synchronized with the start of lock-up release.

As means for lowering the engine output,
For example, ignition timing retard control for retarding the ignition timing of the engine (retard control), fuel supply stop control for stopping fuel supply to an arbitrary engine cylinder (fuel cut control)
In general, the engine torque is reduced by controlling an exhaust gas recirculation amount that recirculates the exhaust of the engine. In the present embodiment, the retard control will be described as an example.

FIG. 2 is a time chart using the horizontal axis as a time axis for explaining the operation when the driver selects the manual shift range (M) from FIG. 1 and performs an upshift with the depression of the accelerator pedal. It is. FIG. 5A shows a vehicle speed VSP that increases with the passage of time, and reference numeral VL denotes a lockup vehicle speed. FIG. 2B shows the rotation speed Ne on the input element side and the rotation speed Nt on the output element side of the torque converter 3 according to the present embodiment with solid lines, and the broken line shows the rotation speed Ne on the input element side according to the conventional technique. is there. Figure (c)
A shift switch signal indicating that the driver has set the shift lever 9 to the upshift (+) position, and FIG. 4D is a lockup signal for turning the lockup solenoid 8 on and off. 3 is in the lockup state, and the OFF signal (lockup release signal) causes the torque converter 3 to be in the converter state. FIG. 5E shows ON and OF of the shift solenoids 6 and 7.
F shows the start timing of the manual upshift, and FIG. 7F shows the output torque T of the engine 1.

More specifically, referring to FIG.
Consider a case in which a shift to manual third speed is attempted while traveling at a vehicle speed V _X (V 2 <V _X ) of a high speed (M ₂ ). If the driver performs a manual upshift by depressing the accelerator pedal during traveling in the lock-up state, as shown in FIG. 2, when t = to, the driver _raises the shift lever 9 once. In order to set the shift (+) position, a manual upshift gear change command is issued to the controller 200 (FIG. C), and the controller 200 turns off the lockup solenoid 8 to release the lockup (FIG. D). At this time, the engine controller 100 starts retard control in synchronization with the lockup release signal (FIG. F).

Accordingly, in a shift accompanied by depression of the accelerator pedal in the lock-up state, in this case, in a manual up-shift shift in the lock-up state, FIG.
As shown in (1), the output torque T of the engine 1 decreases in synchronization with the start of the lockup release. From this, focusing on the input element-side rotational speed Ne during lock-up release,
The input element-side rotational speed Ne corresponds to the shaded area X in FIG.
Is smaller than the conventional one shown by the broken line.

Conventionally, retard control is sometimes performed to reduce the engine torque. Usually, the start and end timings of the retard control are determined by turning on and off the shift solenoids 6 and 7, respectively. It synchronizes with the timing, and does not synchronize with the start of lock-up release unlike the present invention.

Furthermore, in the present embodiment, as shown in FIG. 2, ON shift solenoids 6 and 7, the start time of the shift by OFF, only the start time of the lock-up release t = t _o than the time t ₁ delayed (FIG. E). During the lock-up release operation, a considerable amount of sliding occurs between the lock-up clutches due to slippage. In addition, if a gear shift is performed during the lock-up releasing operation, a torque fluctuation due to the gear shift is transmitted from the output element side of the torque converter 3, and the friction between the lock-up clutches may increase. Therefore, the delaying time t ₁ than the start time of the lock-up release start timing of the shift, in the lock-up release operation, the output element side of the torque converter 3, does not transmit the torque variation due to the shift. Therefore, it is possible to prevent large rubbing caused by shifting during the lock-up releasing operation, and to improve the durability of the lock-up mechanism by protecting the facing of the lock-up clutch.

After the shift is completed, it is necessary to return the output torque of the engine 1 to a normal torque again. However, when the retard control is terminated and the engine torque increases again, a shock due to the fluctuation of the engine torque occurs. Therefore, in the present embodiment, the retard control for reducing the output torque of the engine 1 is performed until the time t _{2 at} which the shift by the ON / OFF of the shift solenoids 6 and 7 is completed, as shown in FIG. Terminate. As a result, the shock that occurs when the engine torque suppressed by the retard control increases again can be absorbed as a shift shock,
There is no discomfort to the driver.

After the gear shifting is completed, FIG.
As shown in (a) and (b), until the vehicle speed VSP exceeds the lock-up vehicle speed VL (= V3), the converter in which the input and output elements of the torque converter 3 slip by ΔN = (Ne−Nt). State. Thereafter, at t = t _L , when the vehicle speed VSP becomes the lock-up vehicle speed VL (FIG. A), the lock-up signal is turned ON again (FIG. D), and the converter state is changed from the converter state in which the slip between the input / output elements is not limited to the input / output elements. Is mechanically directly connected to the lock-up state, and the power transmission efficiency is stabilized.

On the other hand, for example, FIG. 3 is a time chart for explaining a manual upshift in the prior art, and the same parts as those in FIG. During traveling in the lock-up state, t = t _o
When the driver depresses the accelerator pedal to set the shift lever 9 once to the upshift (+) position and issues a manual upshift command (FIG. C), the driver locks to release the lockup of the torque converter 3. The up signal is turned off (FIG. D). ON / OFF of the shift solenoids 6, 7 in synchronization with the lock-up release signal
Control is started and the current selected gear (gear ratio i) is increased by one.
The shift to the selected higher gear (gear ratio i + 1) is performed (FIG. E).

However, in the prior art, as shown in FIG. B, the relationship between the input element-side rotational speed Ne and the output element-side rotational speed Nt at time t ₂ from the start to the end of the manual upshift is locked. After the input element-side rotation speed Ne greatly rises with the release of the up, the gear ratio (i
Since the input element rotation speed Ne decreases to +1), the driver feels strange.

As described above, in the present embodiment, when the lock-up is released at the time of gear shifting accompanied by the depression of the accelerator pedal, the output torque of the engine 1 is reduced in order to prevent the engine from rising due to the lock-up release. Moreover, since the start of the output torque reduction is synchronized with the start of the lock-up release, the engine is prevented from running up when the lock-up of the torque converter 3 is released due to the shift accompanied by the depression of the accelerator pedal. It does not give the driver a sense of discomfort.

Further, since the decrease in the engine torque due to the retard control is terminated during the shift, the shock that occurs when the retard control is terminated and the engine torque increases again can be absorbed as the shift shock, and the driver does not feel uncomfortable. .

In addition, since the shift start time is delayed from the lock-up release start time, large friction between the lock-up clutches caused by shifting during the lock-up release operation is prevented, and the lock-up clutch By protecting the facing, the durability of the lock-up mechanism can be improved.

In the present embodiment, the shift accompanied by the depression of the accelerator pedal has been described as the manual upshift when the manual shift range is selected. However, if the shift involves the depression of the accelerator pedal, P, D, R, and N,
The shift may be an automatic shift range in which an automatic shift is performed for each L range. However, as described in the present embodiment, when the shift accompanied by the depression of the accelerator pedal is a shift in a manual shift range (M) corresponding to a manual shift command from the driver, as shown in FIG. Since the lock-up can be performed even in a low and high engine output area, the engine speeds up particularly when the lock-up is released. Therefore, in a shift involving depression of the accelerator pedal in the manual shift range (M),
The effect of preventing the engine from rising up is more remarkable than that of the automatic transmission range.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a control device for a vehicle power unit according to the present invention.

FIG. 2 is a time chart illustrating a control device for a vehicle power unit according to the present invention.

FIG. 3 is a time chart illustrating a conventional technique.

FIG. 4 is a diagram illustrating a shift control pattern used in an automatic shift (D) range of the automatic transmission.

FIG. 5 is a diagram illustrating a shift control pattern of a manual shift range.

[Explanation of symbols]

 Reference Signs List 1 engine 2 stepped automatic transmission 3 torque converter with lock-up mechanism 4 output shaft 5 control valve unit 6, 7 shift solenoid 8 lock-up solenoid 9 shift lever 10 throttle opening sensor 11 vehicle speed sensor 100 engine controller 200 controller

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // F16H 59:04 59:18

Claims (4)

[Claims] 1. A fluid transmission device having a lock-up mechanism for transmitting power from an engine to a stepped automatic transmission, wherein the fluid is transmitted during a gear shift in a lock-up state in which input / output elements of the fluid transmission device are directly connected. In a vehicle in which the transmission is in a converter state in which the direct connection between the input and output elements has been released, when the lockup is released during a gearshift with the accelerator pedal depressed, the engine blows up due to this lockup release A control device for a power unit for a vehicle, characterized in that the start of engine output reduction for preventing the occurrence of a lock-up is synchronized with the start of lock-up release. 2. The accelerator according to claim 1, wherein the stepped automatic transmission is capable of selecting a manual shift speed corresponding to a manual shift command by a driver while selecting a manual shift range. A shift control accompanied by pedal depression is a shift corresponding to a manual shift command when a manual shift range is selected. 3. The control device for a vehicle power unit according to claim 1, wherein the engine output reduction is terminated during a shift accompanied by depression of an accelerator pedal. 4. The power unit for a vehicle according to claim 1, wherein a start time of a shift accompanied by depression of an accelerator pedal is delayed from a start time of a lock-up release. Control device.