JPH0791535A - Creep preventing device for vehicle equipped with automatic transmission - Google Patents

Abstract

PURPOSE:To perfectly maintain the stop condition of a vehicle without generating a movement of a vehicle due to a creep even in the case where a vehicle is stopped under the condition that a select lever is positioned at a travelling stage. CONSTITUTION:A retarder device 7 is provided in a propeller shaft 4. A controller 13 outputs the control command to a retarder driving device 16 on the basis of the signal from a car-speed sensor 14 and an idle switch 17, and in the case where a vehicle is stopped under the idling condition, the controller 13 fastens the retarder device 7. Thus, when the vehicle is stopped, an output side of an automatic transmission 3 is thereby fixed independently of a position of a select lever 8 to prevent the generation of a movement of a vehicle due to a creep. When the retarder device 7 is fastened, even in the case where the select lever 8 is operated at the time of re-start, a select shock is not generated. Furthermore, when an acceleration pedal is operated to escape from the idle condition, the retarder device 7 is simultaneously opened to improve the responsiveness at the time of starting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a creep prevention device in a vehicle equipped with an automatic transmission.

[0002]

2. Description of the Related Art In a vehicle equipped with an automatic transmission equipped with a torque converter, if the select position of the select lever is left at the travel stage when the vehicle is temporarily stopped,
When the engine is in the first speed state and the engine is idling, a driving force is generated and a creep phenomenon occurs in which the vehicle moves at a low speed. As a countermeasure against such a creep, for example, Japanese Patent Publication No. 48-212 discloses that the first gear, which has a particularly large driving force, is avoided and the creep force is reduced by returning to the second gear in a low load condition such as idling. A shift control device is disclosed in which the first speed is set only when the vehicle starts in a high load state.

[0003]

However, in the above-mentioned conventional apparatus, since it is necessary to switch to the first speed when the vehicle normally restarts, it is necessary to accept the deterioration of the shift shock. Moreover, although the level of creep force is reduced, it does not completely reduce it to a level of zero, and a small amount of creep force is still generated although it is low, and movement of the vehicle cannot be avoided. Therefore, the driver must continue to depress the brake of the vehicle or return the select lever to the neutral position. Therefore, in view of the above-mentioned conventional problems, the present invention relates to a vehicle equipped with an automatic transmission in which even if the select lever is stopped in the traveling stage, the vehicle does not start to move due to creep and the stopped state is completely maintained. An object is to provide a creep prevention device.

[0004]

Therefore, the present invention is directed to a retarder device provided on the output side of an automatic transmission, a vehicle speed detecting means for detecting the traveling speed of a vehicle, and an idling state for detecting an idling state of an engine. According to the signals from the vehicle speed detecting means and the idling state detecting means, the detecting means and the control means for setting the retarder device in the engaged state when the vehicle is in the stopped state and in the idling state are provided.

[0005]

When the vehicle is stopped and idling, the retarder device is engaged and the output side of the automatic transmission is fixed. As a result, unintentional movement of the vehicle due to creep of the automatic transmission is completely prevented regardless of the selected position of the select lever. Since the retarder device is engaged as described above when the vehicle is stopped, when restarting, for example, from the N range to D
Select shock does not occur even when the select lever is operated to the range. Further, the accelerator pedal is stepped on and the retarder device is released at the same time as being released from the idling state, so that the responsiveness of starting is also high.

[0006]

FIG. 1 shows an embodiment of the present invention. An automatic transmission 3 is connected to an engine 1 via a torque converter 2, and an output of the automatic transmission 3 is transmitted to a differential gear 6 of a drive axle 5 by a propeller shaft 4. The automatic transmission 3 has its transmission mechanism section 11 and
Upon receiving a control command from the controller 13, the transmission mechanism unit 1
1, a vehicle speed sensor 14 for outputting a vehicle speed signal based on the rotational speed of the output shaft is provided. The hydraulic control device 12 is connected to the select lever 8 and realizes a required shift speed based on the selected position and a control command from the controller 13. Although not particularly shown, the hydraulic control device 12 is provided with a manual valve, and this manual valve is connected to the above-mentioned select lever 8 via a manual plate.

A multi-plate clutch type retarder device 7 is attached between the propeller shaft 4 and the vehicle body side, and is actuated by a retarder drive device 16. The retarder device 7 is adapted to generate a braking force on the propeller shaft 4 by engaging the multi-plate clutch.

The engine is provided with a throttle opening sensor 15 and an idle switch 17. The throttle opening sensor 15 and the idle switch 17 are connected to the controller 13, and the vehicle speed sensor 14 and the retarder switch 18 are also connected to the controller 13. The microcomputer provided in the inside of the controller 13 performs arithmetic processing to represent the normal throttle opening. Based on the engine load, the vehicle speed, etc., the control command for shifting the shift speed is sent to the hydraulic control device 12.

Further, when the retarder switch 18 is turned on, the controller 13 sends a retarder control command to the retarder drive device 16 according to the traveling state, and controls the retarder device 7 to operate. The retarder drive device 16 performs slip control or fastening control of the retarder device 7 according to the retarder control command.

Next, FIG. 2 shows a flow of processing in the controller 13 for controlling the retarder device 7. First, in step 101, it is checked whether the retarder switch 18 is turned on. If the retarder switch 18 is on, the routine proceeds to step 102, where the state of the idle switch 17 is checked. When the idle switch 17 is on and the engine is in the idle state, that is, when the accelerator pedal (not shown) is released, the vehicle speed is set to 0 k in the next step 103.
m / h, that is, whether or not the vehicle is stopped is checked.

If the vehicle is stopped, step 1
At 04, a retarder control command for engaging the multiple disc clutch of the retarder device 7 is output to the retarder drive device 16. By engaging the multi-plate clutch, the propeller shaft 4 is fixedly locked to the vehicle body side. When the vehicle is not stopped, the routine proceeds to step 105, where a retarder control command for half-engaging the multi-disc clutch of the retarder device 7 in the slip state is output. By this slip control, a resistance according to the rotation is added to the propeller shaft 4. On the other hand, when the retarder switch 18 is off or the engine is not in the idle state in step 102 in the check in step 101, the process proceeds to step 106 and the retarder device 7 is deactivated.

Since the embodiment is constructed as described above, when the retarder switch 18 is turned on during traveling, a normal retarder function is exerted and, for example, an effective auxiliary braking force on a long slope is obtained. Further, when creeping is useful such as driving in a traffic jam or entering a garage, the retarder device 7 is opened by turning off the retarder switch 18, so that normal creeping can be obtained.

When the accelerator pedal is released and the vehicle is stopped at a vehicle speed of 0 while the retarder switch 18 is turned on, the retarder device 7 is engaged and the propeller shaft 4 on the output side of the automatic transmission is engaged. Is fixed,
As a result, unintentional movement of the vehicle due to creep is completely prevented regardless of the selected position of the select lever 8.

Further, according to this embodiment, by engaging the retarder device 7 in this stopped state, on the other hand, when the vehicle restarts, for example, when the select lever 8 is operated from the N range to the D range, the select shock does not occur. On the other hand, the retarder device 7 is opened at the same time when the accelerator pedal is depressed. Therefore, as compared with the conventional one that stands by at the second speed during idling as described above, the response is high. In the embodiment, the idle switch 17 is connected to the throttle opening sensor 15
However, the present invention is not limited to this, and the throttle opening sensor may be used in common and a signal of the opening of zero may be used.

[0015]

As described above, according to the present invention, the retarder device is provided on the output side of the automatic transmission, and the retarder device is engaged when the vehicle is in the stopped state and in the idling state. The device is fastened and the output side of the automatic transmission is fixed, and even if the select position of the select lever is in any position, it is possible to completely prevent unintentional movement of the vehicle due to creep of the automatic transmission. In addition, since the retarder device is engaged as described above when the vehicle is stopped, the select shock does not occur even when the select lever is operated when the vehicle restarts, and the retarder device is released at the same time when the accelerator pedal is released from the idling state. Is open, and the responsiveness of starting is high.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing a control flow.

[Explanation of symbols]

1 Engine 2 Torque Converter 3 Automatic Transmission 4 Propeller Shaft 5 Drive Axle 6 Differential Gear 7 Retarder Device 8 Select Lever 11 Shift Mechanism 12 Hydraulic Controller 13 Controller (Control Means) 14 Vehicle Speed Sensor (Vehicle Speed Detecting Means) 15 Throttle Opening Sensor 16 Retarder drive device 17 Idle switch (idling state detection means) 18 Retarder switch

Claims (1)

[Claims] 1. A retarder device provided on an output side of an automatic transmission, and a vehicle speed detecting means for detecting a traveling speed of a vehicle,
Based on signals from the idling state detecting means for detecting the idling state of the engine and the vehicle speed detecting means and the idling state detecting means, the control means for putting the retarder device in the engaged state when the vehicle is in the stopped state and in the idling state A creep prevention device for a vehicle equipped with an automatic transmission, comprising: