JPH055434A - Automatic transmission for vehicle - Google Patents

Abstract

(57) [Summary] [Purpose] To effectively reduce the torque impact applied to the automatic transmission mechanism when the shift lever is switched from the stop range to the travel range due to an abnormal operation. When the shift lever is switched from a stop range such as a neutral range to a travel range such as a drive range when the vehicle speed is below a predetermined speed, the control unit 13 is stored in a storage area 13A. The control region determination map is read out, and it is determined whether or not it is within the control region of the control region determination map from the detected torque output from the torque sensor 7 and the torque increment value obtained by differentiating the detected torque. To do. When in the control region, the control unit 13 controls the fuel injection valve 8, the ignition coil 11, the sub throttle valve 12
A control signal is output to control the injection amount, the ignition timing, and the throttle to thereby reduce the torque of the engine 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission device for a vehicle, which is mounted on a vehicle such as an automobile and is suitable for automatic transmission by operating a shift lever.

[0002]

2. Description of the Related Art Generally, an engine mounted on a vehicle,
An automatic transmission mechanism that is connected to a drive shaft of the engine and that transmits a torque input from the drive shaft to an output shaft.
An automatic transmission for a vehicle, which is provided in the vehicle and includes a shift lever that is operated to switch between a traveling range and a stop range for traveling and stopping the vehicle, is known.

Here, the automatic transmission mechanism is generally a torque converter in which a pump impeller is connected to a drive shaft of an engine and a turbine impeller is connected to an input shaft, and an input from the torque converter via the input shaft. A transmission that multi-stages the generated engine torque (engine speed) by a transmission gear such as a planetary gear, a shift clutch that connects the transmission and the input shaft by increasing the clutch operating oil pressure, and the clutch operating oil pressure. It is composed of a variable speed control valve that is variably controlled.

Then, the driver shifts the shift lever from a stop range such as a neutral range (hereinafter referred to as N range) and a parking range (hereinafter referred to as P range) to a drive range (hereinafter referred to as D range) and a reverse range (hereinafter referred to as D range). , R range) or the like, the accumulator provided in the middle of the hydraulic pipe for supplying the clutch operating oil gradually increases the clutch operating oil pressure. As a result, the speed change clutch is connected while absorbing shock, and the engine torque of the input shaft is transmitted to the speed change gear. Then, the clutch operating oil pressure is variably controlled by the shift control valve, so that the shift gear shifts the engine torque transmitted from the input shaft in a plurality of stages to output the output shaft, the output shaft and the drive wheels of the vehicle. It is transmitted to a propeller shaft arranged between the vehicle and the vehicle, and the vehicle moves forward and backward.

[0005]

By the way, according to the above-mentioned prior art, the shift lever is switched from the N range to the D range while the accelerator pedal is strongly depressed due to an erroneous operation by a driver unfamiliar with driving. In this case, the accumulator does not buffer the hydraulic pressure in time, and the clutch operating hydraulic pressure rises rapidly and the speed change clutch is engaged. Is transmitted rapidly to.

Therefore, in the above-mentioned prior art, not only the vehicle suddenly starts and the danger increases, but also an excessive torque (torque shock) is applied to the transmission gears, the transmission clutch, the output shaft, etc. There is a problem in that the speed change gears are damaged and durability, life, etc. are greatly reduced. Also,
To deal with the excessive shift impact that occurs during this abnormal operation,
Since parts such as the transmission gear, output shaft, and propeller shaft must be formed with a strength higher than that required under normal operating conditions, the weight of the automatic transmission as a whole and the moment of inertia of the output shaft, etc. can be greatly reduced. Increased to
There is a problem that fuel efficiency and exercise performance of the vehicle are significantly reduced.

The present invention has been made in view of the above-mentioned problems of the prior art, and it is possible to effectively reduce the torque impact applied to the automatic transmission mechanism when the shift lever is switched from the stop range to the traveling range by an abnormal operation. An object of the present invention is to provide an automatic transmission for a vehicle as described above.

[0008]

The features of the configuration adopted by the present invention in order to solve the above-mentioned problems are that a torque detector provided on the output side of the automatic speed change mechanism for detecting output torque and a shift lever are provided. Range switching determination means for determining whether the stop range has been switched to the running range, vehicle speed determination means for determining whether the speed of the vehicle is less than or equal to a predetermined speed, and based on the detected torque from the torque detector A torque determining means for determining whether or not the output torque is an excessive torque, and the range switching determining means for determining that the driving range has been switched to, and the vehicle speed determining means for determining that the vehicle speed is less than or equal to a predetermined speed, and It is provided with engine torque reducing means for reducing the torque output from the engine when the torque determining means determines that the torque is excessive.

Further, the torque determination means determines that the output torque is excessive based on a control region determination map formed by a detected torque output from the torque detector and a torque increment value obtained by differentiating the detected torque. It is preferable to determine whether there is.

[0010]

With the above structure, when the range switching determination means determines that the vehicle has been switched to the running range, the vehicle speed determination means determines that the speed is less than or equal to the predetermined speed, and the torque determination means determines that the torque is excessive, the engine torque decreases. Means reduce the torque output from the engine and prevent excessive engine torque from being applied to the automatic transmission.

Further, whether the output torque is excessively large, based on a control region judgment map composed of the detected torque output from the torque detector and the torque increment value obtained by differentiating the detected torque. It can be determined whether or not.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In the figure, 1 is an engine mounted on a vehicle, 2 is an automatic transmission mechanism provided on the output side of the engine 1, and the automatic transmission mechanism 2 is a drive shaft (not shown) of the engine 1. Torque converter 3 connected to
And a transmission 5 for transmitting engine torque input from the torque converter 3 via an input shaft in multiple stages by a transmission gear such as a planetary gear (not shown) and transmitting the output torque to an output shaft 4. The clutch operating hydraulic pressure is variably controlled by a speed change clutch (not shown) provided in the machine 5 and connecting the transmission 5 and the input shaft by the increase of the clutch operating hydraulic pressure, and a control signal from a control unit 13 described later. The shift control valve 6 is included. Then, the automatic transmission mechanism 2 shifts the engine torque transmitted from the engine 1 via the torque converter 3 in multiple stages by the transmission 5, and transmits the shifted rotation speed (torque) to the output shaft 4 to propeller the propeller. The shaft (not shown) is rotated.

Reference numeral 7 denotes a torque sensor as a torque detector provided near the output shaft 4, and the torque sensor 7
Is composed of, for example, a 4-coil type magnetostrictive torque sensor. The torque sensor 7 detects the torque of the output shaft 4 and outputs it as the detected torque Vt to the control unit 13.

Reference numeral 8 denotes a plurality of fuel injection valves (only one is shown) provided in the cylinder head of the engine 1. The fuel injection valve 8 is connected to a fuel pump (none of which is shown) via a fuel pipe or the like. It is connected. The fuel injection valve 8 receives the fuel injection signal from the control unit 13,
The fuel supplied from the fuel pump is injected into a cylinder (not shown) of the engine 1.

Reference numeral 9 denotes a shift lever sensor which is attached to a shift lever (not shown) mounted on the vehicle and comprises an inhibitor switch or the like. The shift lever sensor 9 has a shift lever of N range, P range and D range. , R range or the like, which range is being switched is detected, and this detection signal is output as a shift position signal to the control unit 13 described later.

Reference numeral 10 denotes a vehicle speed sensor, and the vehicle speed sensor 1
0 detects the speed of the vehicle and outputs it as a vehicle speed signal V to the control unit 13. Reference numeral 11 denotes an ignition coil, and the ignition coil 1
1 is a control signal from the control unit 13,
A high voltage for ignition is applied to an ignition plug (not shown) to ignite the ignition plug.

Reference numeral 12 denotes a sub-throttle valve provided in the middle of the intake manifold, and when the control signal is output from the control unit 13, the sub-throttle valve 12 variably adjusts the valve opening degree thereof to adjust the intake air amount. Is to control.

Reference numeral 13 denotes a control unit composed of a microcomputer or the like, and a storage area 13A of the control unit 13 has a torque control processing program shown in FIGS. 2 and 3, and a control area determination map shown in FIG. 14 and 14 are stored. In addition, the control unit 13 has a torque sensor 7, a shift lever sensor 9, a vehicle speed sensor 10, a crank angle sensor,
A throttle sensor (neither is shown) is connected,
The shift control valve 6, the fuel injection valve 8, the ignition coil 11, and the sub throttle valve 12 are connected to the output side.

Here, the control area determination map 14 is
As shown in FIG. 4, the detected torque Vt from the torque sensor 7
And the torque increment value V obtained by differentiating the detected torque Vt
The relationship with t'is stored as a map, and the control area determination map 14 has a predetermined threshold level Vt0.
Is formed according to the magnitude of the torque increment value Vt ', and is formed on the upper side of the boundary line 14A.
The control region 14B performs the engine torque reduction process, and the non-control region 14C formed below the boundary line 14A and in which the engine torque reduction process is not performed.
Then, the control region determination map 14 shows the detected torque Vt.
Is above the threshold level Vt0, but if the torque increment value Vt 'is small, the engine torque reduction processing is not performed. Even if the detected torque Vt is below the threshold level Vt0, the torque increment value Vt is decreased.
When t'is large, the boundary line 14A is set so as to perform the engine lowering process, and thereby the engine torque lowering process can be efficiently performed.

The vehicular automatic transmission according to this embodiment has the above-mentioned structure. Next, the torque control process will be described with reference to FIGS. 2 to 4.

First, when the engine 1 starts and the processing operation starts, in step 1, the shift lever sensor 9
The shift position signal output from is read, and in step 2, based on the shift position signal, it is determined whether or not the shift lever is switched from the N range and P range as the stop range to the D range and R range as the travel range. judge. Here, in a vehicle equipped with an automatic transmission, a safety circuit is generally incorporated so that the engine 1 cannot be started unless the shift lever is in the N range. Therefore, when the processing operation starts, the shift lever is in the N range. It is in.

If "YES" is determined in the step 2, it means that the shift lever has moved from the stop range such as the N range to the running range such as the D range. Therefore, the process proceeds to step 3 and the "step 2" is executed. When it is determined to be "NO", the routine returns to the main routine and the normal automatic shift processing is performed. Next, in step 3, the timer T is started, and in step 4, this timer T is previously stored in the storage area 1.
It is determined whether or not the predetermined time T1 stored in 3A has been reached. Here, this predetermined time T1 is, for example, in the range of 0.0 to 1.5 seconds in order to perform the engine torque reduction processing described later only for the time during which the shift clutch is engaged, that is, during the time when a torque shock occurs during shifting. Preferably 0.3-0.7
It is set in the range of seconds.

When it is determined "YES" in step 4, it means that the timer T has not yet reached the predetermined time T1, so the process moves to step 5 and the vehicle speed signal V from the vehicle speed sensor 10 is read. In step 4, "N
If it is determined to be "O", it means that the timer T has exceeded the predetermined time T1, and therefore the routine returns to perform the normal automatic shift processing.

In the next step 6, it is determined whether the vehicle speed signal V read in step 5 is equal to or lower than the predetermined speed V1 stored in the storage area 13A in advance. here,
The predetermined speed V1 is, for example, 0 to 10 so that the engine torque reduction process is performed only while the vehicle is substantially stopped.
It is set in the range of km / h. When the determination in step 6 is "YES", the vehicle speed signal V is equal to or lower than the predetermined speed V1, so the process proceeds to step 7 shown in FIG. Further, when it is determined to be "NO" in step 6, when the vehicle speed signal V is higher than the predetermined speed V1, for example, while the vehicle is traveling, the shift lever is switched from the D range to the N range and then to the D range again. Since it is a case where it is not necessary to reduce the engine torque, for example, the routine returns and the normal automatic shift processing is performed.

Next, in FIG. 3, in step 7, the detected torque Vt from the torque sensor 7 is read, and in step 8
Then, the detected torque Vt is differentiated to obtain a torque increment value Vt ′ which is the amount of change in torque per unit time.
In the next step 9, the control area determination map 14 shown in FIG. 4 is read from the storage area 13A.

Then, in step 10, it is determined from the detected torque Vt from the torque sensor 7 and the torque increment value Vt 'obtained in step 8 whether or not it is within the control region 14B of the control region determination map 14. To do. If “YES” is determined in this step 10, it means that excessive torque is applied to the output shaft 4, and therefore steps 11 to 1 described later are performed.
The engine torque reduction process shown in 3 is performed. Further, when it is determined to be “NO” in step 10, the non-control area 1
Since it is in 4C, the routine returns and the normal automatic shift processing is performed, as in steps 2, 4, and 6.

Next, at step 11, a control signal is output to the sub-throttle valve 12, and the sub-throttle valve 12 is controlled.
The engine torque is reduced by closing the valve and reducing the intake air amount. In the next step 12,
The pulse width of the fuel injection signal output to the fuel injection valve 8 is adjusted to reduce the fuel injection amount injected from the fuel injection valve 8 into the engine 1 to reduce the engine torque. Then, in step 13, the engine torque is reduced by adjusting the control signal output to the ignition coil 11 to retard the ignition timing of the spark plug, and the process returns to step 2. Then, the steps 4, 6, 10
Until it is judged as “NO” in any of the
The engine lowering process of 13 is repeated.

Thus, according to this embodiment, when the vehicle speed V of the vehicle is equal to or lower than the predetermined speed V1, the shift lever is moved to N.
When the stop range such as the range is switched to the travel range such as the D range, the control unit 13 actually outputs the output torque to the output shaft 4 from the detected torque Vt output from the torque sensor 7 and the torque increment value Vt '. Control region 14B of control region determination map 14 based on the applied torque value
If it is within the control region 14B, it is possible to perform the engine torque reduction processing for a predetermined time T1.

As a result, when the abnormal operation is performed at time t0, as indicated by the characteristic line 15 shown by the solid line in FIG.
The torque of the engine 1 can be promptly reduced, and the torque of the output shaft 4 can be surely prevented from suddenly rising as shown by a characteristic line 16 shown by a dot-dash line in the prior art, and the vehicle can be prevented from suddenly starting. To improve safety.

Further, it is possible to reliably prevent an excessive torque from being applied to the output shaft 4, the transmission 5, the propeller shaft and the like, and prevent the transmission 5 and the like from being damaged, resulting in durability, life and reliability. Etc. can be greatly improved. further,
The transmission 5 and the like can be formed with normal mechanical strength required in a normal operation state, the entire automatic transmission mechanism 2 can be significantly reduced in weight, and the moment of inertia of the output shaft 4 and the like can be reduced. Fuel efficiency and exercise performance can be greatly improved.

The control area determination map 14 shown in FIG.
Since it is configured to determine whether the output torque is excessive based on the above, the engine torque can be efficiently reduced only when necessary based on the torque value actually applied to the output shaft 4. The reliability of the automatic transmission for a vehicle can be improved.

In the above embodiment, of the programs shown in FIGS. 2 and 3, steps 1 and 2 show concrete examples of the range switching judging means which is a constituent feature of the present invention, and steps 5 and 6 show vehicle speed judgment. A concrete example of the means is shown, and Steps 7-1
0 indicates a concrete example of the torque determination means, and steps 11 to 1
3 is a specific example of the engine torque reducing means.

Further, in the above-described embodiment, as a concrete example of the engine torque lowering means, three controls of throttle control, injection amount control and ignition timing control are performed as shown in steps 11 to 13, but The invention is not limited to this, and for example, only one or two of steps 11 to 13 may be executed.

Further, in the above embodiment, the torque sensor 7 as the torque detector is described as being provided in the vicinity of the output shaft 4, but instead of this, for example, between the torque converter 3 and the transmission 5. It may be provided in.

[0036]

As described above in detail, according to the present invention, it is determined that the range switching determination means has switched to the running range,
When the vehicle speed determination means determines that the vehicle speed is less than or equal to the predetermined speed and the torque determination means determines that the torque is excessive, the engine torque reducing means reduces the torque output from the engine, and the excessive engine torque causes the automatic transmission mechanism to shift. Can be prevented from joining. As a result, it is possible to reliably prevent the output torque from suddenly increasing, prevent the vehicle from suddenly starting, and improve safety. Further, it is possible to prevent the output shaft, the automatic transmission mechanism, and the like from being damaged, and it is possible to improve durability, life, reliability, and the like. Further, since the automatic transmission mechanism and the like can be formed with normal mechanical strength in a normal operation state, the automatic transmission device for a vehicle can be made lighter, and the fuel consumption and exercise performance of the vehicle can be improved.

Whether the output torque is excessively large, based on a control region judgment map composed of the detected torque output from the torque detector and the torque increment value obtained by differentiating the detected torque. Since it can be determined whether or not the engine torque can actually be reduced based on the output torque actually acting on the automatic transmission mechanism, the engine torque can be efficiently reduced and reliability can be improved. ..

[Brief description of drawings]

FIG. 1 is a block diagram showing an automatic transmission for a vehicle according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a torque control process.

FIG. 3 is a flowchart showing a torque control process subsequent to FIG.

FIG. 4 is an explanatory diagram showing a control area determination map.

FIG. 5 is a characteristic diagram showing a change in output shaft torque when a torque shock occurs.

[Explanation of symbols]

 1 Engine 2 Automatic Transmission Mechanism 4 Output Shaft 7 Torque Sensor (Torque Detector) 9 Shift Lever Sensor 10 Vehicle Speed Sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yutaka Muraoka, 1671 Kasukawa-cho, Isesaki-shi, Gunma 1 Nippon Electric Equipment Co., Ltd. Incorporated (72) Inventor Nobuaki Kobayashi 1671, Kasukawa-cho, Isesaki-shi, Gunma Nippon Electric Equipment Co., Ltd.

Claims (1)

Claim: What is claimed is: 1. An engine mounted on a vehicle, and an automatic speed change mechanism, which is connected to a drive shaft of the engine and changes a torque input from the drive shaft and transmits the torque to an output shaft. An automatic transmission for a vehicle, comprising: a shift lever provided on the vehicle and configured to switch between a travel range and a stop range to drive and stop the vehicle, the automatic transmission being provided on the output side of the automatic transmission mechanism to output torque. A torque detector for detecting, a range switching determining means for determining whether or not the shift lever is switched from a stop range to a traveling range, and a vehicle speed determining means for determining whether or not the speed of the vehicle is below a predetermined speed. And a torque determination means for determining whether or not the output torque is excessive torque based on the detected torque from the torque detector, and the range switching determination means for the traveling range. Engine torque reduction means for reducing the torque output from the engine when it is determined that the vehicle speed has been switched, the vehicle speed determination means determines that the vehicle speed is less than or equal to a predetermined speed, and the torque determination means determines that the torque is excessive torque. An automatic transmission for a vehicle, comprising: 2. The torque determining means determines that the output torque is excessive based on a control region determination map including a detected torque output from the torque detector and a torque increment value obtained by differentiating the detected torque. The automatic transmission for a vehicle according to claim 1, wherein it is determined whether or not there is.