JP4206601B2 - Auto clutch control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic clutch control device.
[0002]
[Prior art]
The auto clutch includes a clutch interposed between the transmission and the engine, a clutch actuator for connecting / disconnecting the clutch, and a control unit for giving a connection / disconnection command to the clutch actuator, and is controlled when starting, shifting, and stopping. The clutch actuator is operated based on a connection / disconnection command issued from the unit, and the clutch is appropriately connected / disconnected each time.
[0003]
[Problems to be solved by the invention]
In a vehicle equipped with such an auto clutch, when a predetermined braking force is generated by depressing a brake pedal with the clutch engaged, various kinds of engine speed reduction, vehicle speed reduction, accelerator opening, etc. Control is performed so that the clutch is disengaged by a clutch disengagement command issued from the control unit to the clutch actuator when a detected value from a sensor that monitors the parameters as needed satisfies a certain condition.
[0004]
However, especially when the engine is running at a low engine speed with the clutch engaged, if the brake pedal is depressed to generate a predetermined braking force, the engine speed will be low and the clutch will be disengaged by a normal clutch disengagement operation. There was a problem that it was easy to cause engine stalls in time. On low μ roads, the tire may lock when the brake pedal is depressed. With the above normal clutch disengagement control, the disengagement of the clutch is not in time, and the possibility of stalling is very high.
[0005]
In order to prevent the engine from being stopped, conventionally, when the brake pedal is suddenly depressed or when wheel lock occurs in a snowy road, the detection signal from the braking force detection means such as brake air pressure is used. On the basis of this, there has been a proposal (Japanese Patent Laid-Open No. 62-64641) for performing clutch disengagement control. That is, this proposal detects sudden braking according to the brake air pressure generated by the depression operation of the brake pedal, and performs a clutch disengagement operation based on the detected signal, so that deceleration is suddenly performed. This was to prevent the engine from stopping.
[0006]
However, in the conventional example, since the clutch disengagement operation is performed based on the signal that detects the sudden braking state of the brake, the clutch disengagement operation is performed in the same manner for the sudden braking in the high speed traveling or the high vehicle speed range. The driving feeling suddenly deteriorated due to the decrease in driving force and the release of the engine brake, causing the driver to feel uncomfortable.
[0007]
An object of the present invention, which was created in view of the above circumstances, is to provide an automatic clutch control device that can prevent an engine stall when a brake pedal is depressed during low engine rotation.
[0008]
[Means for Solving the Problems]
The present invention, which was created to achieve the above object, is an automatic clutch control device that appropriately connects and disconnects a clutch by a clutch actuator when starting, shifting, and stopping, and is turned on at a predetermined brake pressure when a brake pedal is depressed. A brake switch; an engine rotation sensor that detects an engine speed; and a control unit that transmits a clutch emergency disconnection command to the clutch actuator when the brake switch is on and the engine speed is equal to or lower than a predetermined speed. predetermined brake pressure the brake switch is turned on, based on the correlation of the road surface mu brake pressure is set to a brake pressure can be locked tire at a predetermined road surface mu, the control unit, the brake pedal When depressed, the brake pressure Stores the engine speed when another brake switch that is turned on at a low predetermined brake pressure is turned on, and turns on at the higher predetermined brake pressure on condition that the engine speed is equal to or lower than the predetermined speed. When the brake switch is turned on, a clutch emergency disconnection command is transmitted to the clutch actuator .
[0009]
According to the present invention, when the brake pedal is depressed and the brake switch is turned on, if the engine speed detected by the engine speed sensor is equal to or lower than the predetermined speed, a clutch emergency disconnection command is transmitted from the control unit to the clutch actuator. And the clutch is quickly disengaged. Thus, when the engine is running at a low speed while the clutch is connected, when the brake pedal is depressed to generate a predetermined braking force, the clutch can be quickly disconnected before the engine stalls, and engine stall is prevented. In particular, on a low μ road, the clutch is disengaged before the tire locks during braking, which is effective in preventing engine stall.
[0010]
Further, since the clutch disengagement control is not performed during the high engine speed traveling, it is possible to avoid a sudden decrease in driving force and a sudden deterioration in operation feeling due to the release of the engine brake. Therefore, the driver does not feel uncomfortable.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
[0012]
2 is a schematic diagram of an automatic transmission having an auto clutch according to the present embodiment, FIG. 1 is a flowchart showing a control flow of the control device for the auto clutch, and FIG. 3 is a diagram of a brake switch of the control device. It is explanatory drawing which shows a characteristic.
[0013]
As shown in FIG. 2, the auto clutch 1 includes a clutch 3 interposed between an engine (not shown) and the transmission 2, a clutch actuator 4 that connects / disconnects the clutch 3, and a connection / disconnection to the clutch actuator 4. And a control unit 5 for giving a command. The clutch actuator 4 is operated based on a connection / disconnection command issued from the control unit 5 when starting, shifting, or stopping, and the clutch 3 is appropriately connected / disconnected each time.
[0014]
The clutch 3 includes a flywheel 6 (drive plate) connected to the crankshaft of the engine, a driven plate 7 disposed opposite to the flywheel 6, and a pressure plate 8 that sandwiches the driven plate 7 between the flywheel 6. And have. The clutch actuator 4 appropriately controls the movement of the pressure plate 8 between the flywheel 6 side and the opposite side based on the connection / disconnection command issued from the control unit 5, and connects / disconnects the clutch 3 to transmit the engine output to the transmission 2. On / off for.
[0015]
As shown in FIG. 2, the transmission 2 includes an input shaft 9 coupled to the driven plate 7, a main shaft 10 disposed coaxially with the input shaft 9, an output shaft 11 disposed coaxially therewith, and the shafts 9, 10. , 11 and a counter shaft 12 arranged in parallel. A spline 13 is fixed to the input shaft 9 and an input gear 14 is pivotally supported. A spline 15 is fixed to the input gear 14.
[0016]
The counter shaft 12 includes an input counter gear 16 that meshes with the input gear 14, a fourth speed counter gear 17, a third speed counter gear 18, a second speed counter gear 19, a first speed counter gear 20, and a reverse counter gear 21. Are fixed. On the other hand, the main shaft 10 has a 4-speed main gear 22 meshed with the 4-speed counter gear 17, a 3-speed main gear 23 meshed with the 3-speed counter gear 18, and a 2-speed main gear 24 meshed with the 2-speed counter gear 19; A first-speed main gear 25 that meshes with the first-speed counter gear 20 and a reverse main gear 27 that meshes with the reverse counter gear 21 via an idle gear 26 are pivotally supported.
[0017]
Splines 28 and 29 are fixed on the left and right sides of the 4-speed main gear 22, respectively. A spline 30 is fixed on the left side of the 3-speed main gear 23, and a spline 31 is positioned on the right side of the 2-speed main gear 24. A spline 32 is fixed to the left of the first-speed main gear 25, and a spline 33 is fixed to the right of the reverse main gear 27. The main shaft 10 has a spline 34 fixed between the splines 29 and 30, and a spline 35 fixed between the splines 31 and 32, and is positioned to the right of the spline 33. The spline 36 is fixed.
[0018]
The spline 13 is provided with a sleeve 37 that meshes and connects adjacent splines 13 and 15 (13 and 28) to each other, or meshes only with the central spline 13, and the spline 34 includes adjacent splines 34 and 29 (34, 30) A sleeve 38 which meshes with each other or meshes only with the central spline 34 is provided, and the spline 35 is meshed with adjacent splines 35, 31 (35, 32) or only with the central spline 35. A meshing sleeve 39 is provided, and the spline 36 is provided with a sleeve 40 that meshes and connects adjacent splines 33, 36 or meshes only with the spline 36.
[0019]
As shown in FIG. 2, a sun gear 42 of the planetary gear mechanism 41 is fixed to the right end portion of the main shaft 10. Around the sun gear 42, a plurality of planetary gears 43 are arranged. Each planetary gear 43 is pivotally supported together by a carrier 44. A ring gear 45 is disposed outside the planetary gears 43. A spline 46 is fixed to the ring gear 45, and a spline 48 is fixed to the transmission case 47. An output shaft 11 is fixed to the carrier 44, and a spline 49 is fixed to the output shaft 11.
[0020]
The splines 46, 48, and 49 are provided with sleeves 50 that mesh and connect any one of adjacent splines. Further, a shift fork (not shown) is engaged with each of the sleeves 37, 38, 39, 40, 50 so that the sleeve 37, 38, 39, 40, 50 is moved in the axial direction as appropriate by a gear shift unit (not shown) that operates in response to a command from the control unit 5. It has become. For example, when the sleeve 37 is positioned on the spline 13, the rotation of the input shaft 9 is not transmitted to the input gear 14, and the counter shaft 12, the main shaft 10, and the output shaft 11 are stopped.
[0021]
When the sleeve 13 is moved onto the splines 15, 13, the rotation of the input shaft 9 is accelerated and transmitted to the counter shaft 12 via the input gear 14 and the input counter gear 16, and all the counter gears 16 to 21 and the main gear are transmitted. 22-27 rotate. When the sleeve 37 is switched and moved on the splines 13 and 28, the rotation of the input shaft 9 is transmitted to the countershaft 12 by being decelerated to the countershaft 12 via the 4-speed main gear 22 and the 4-speed counter gear 17. To 21 and main gears 22 to 27 are decelerated from before switching and rotate.
[0022]
Here, if the sleeves 38, 39, 40 are positioned on the splines 34, 35, 36, the main gears 22-27 only idle on the main shaft 10, and the main shaft 10 rotates. However, when the sleeve 39 is positioned on the splines 35 and 32, the first speed is achieved, and the main shaft 10 rotates at the first speed. Similarly, when the sleeve 39 is positioned on the splines 35 and 31, the second speed is set, when the sleeve 38 is positioned on the splines 34 and 30, the third speed is set, and when the sleeve 38 is positioned on the splines 34 and 29, the fourth speed is set. The main shaft 10 rotates at an equivalent speed of 2nd speed, 3rd speed, 4th speed.
[0023]
At this time, the sun gear 42 fixed to the right end of the main shaft 10 rotates at the same speed as the main shaft 10 to rotate the planetary gear 43 and the ring gear 45. When the sleeve 50 is in the position on the splines 48 and 46, the rotational speed of the sun gear 42 is decelerated at a predetermined reduction ratio of the planetary gear mechanism 41 and transmitted to the output shaft 11, and the sleeve 50 is on the splines 46 and 49. At the position, the rotation of the sun gear 42 is transmitted to the output shaft 11 in a directly connected state.
[0024]
In this way, the transmission 2 is shifted in two steps by the split transmission gear mechanism 51 shown in FIG. 2, is shifted in four steps by the downstream main transmission gear mechanism 52, and is shifted in two steps by the downstream range transmission gear mechanism 53. The speed is changed to 2 × 4 × 2 = 16 speeds. The auto clutch 1 operates the clutch actuator 4 based on a connection / disconnection command issued from the control unit 5 when shifting the transmission 2 or starting / stopping the vehicle, and appropriately connects / disconnects the clutch 3 each time. is there.
[0025]
Now, as shown in FIG. 2, the control device 54 of the auto clutch 1 according to the present embodiment depresses the brake switch A that is turned on with the first brake pressure when the brake pedal 55 is depressed, and further depresses the brake pedal 55. And a brake switch B that is turned on at a second brake pressure higher than the first brake pressure. In the present embodiment, “second brake pressure” corresponds to “predetermined brake pressure” in the claims, and “brake switch B” corresponds to “brake switch” in the claims.
[0026]
As shown in FIG. 3, the brake switch A is turned on at a brake pressure of 0.3 kgf / cm ² and merely turns on a stop lamp. When the brake switch A is turned on, almost no braking force is generated in the tire. As shown in FIG. 3, the brake switch B is turned on with a brake pressure = ² kgf / cm ² , and a predetermined braking force is generated on the tire when the brake switch B is turned on. Specifically, the braking force at the brake pressure = ² kgf / cm ² is set to such an extent that the tire can be locked on a low μ road.
[0027]
As shown in FIG. 2, an engine rotation sensor 56 that detects the engine speed is disposed in the vicinity of the flywheel 6. The engine rotation sensor 56 detects the rotation speed of the engine connected to the flywheel 6 by detecting the rotation speed of the flywheel 6. The control unit 5 for giving an operation command to the clutch actuator 4 is written with a program for transmitting a clutch emergency disconnection command to the clutch actuator 4 when the brake switches A and B are both on and the engine speed is equal to or lower than the predetermined speed. It is.
[0028]
A control flow of such a program is shown in FIG.
[0029]
As shown in the figure, after the start, it is determined in step 1 that the brake switch A = off. Since the answer is yes when the brake pedal 55 is not depressed, the flag 1 is turned on in step 2 and the flag 2 is turned off in step 3. And it becomes an end and returns to the start again. Such circulation is performed many times within one second. As a result, when the brake pedal 55 is not depressed, the flag 1 is set on and the flag 2 is set off.
[0030]
Next, when the brake pedal 55 is depressed, the brake switch A is turned on, step 1 becomes “no” and the process proceeds to step 4, and since flag 1 is on, step 4 becomes “yes” and the process proceeds to step 5. In step 5, flag 1 is turned off, and in step 6, the current engine speed is stored. The engine speed is detected by the engine speed sensor 56 shown in FIG. 2, and the detected value is stored in the control unit 5.
[0031]
Then, in step 7, it is determined that the storage engine speed ≤ 1000 rpm. If this is yes, flag 2 is turned on in step 8, and the start is started from the end. If the brake pedal 55 continues to be depressed, the brake switch A is on, so step 1 becomes no. First, the flag 1 is turned off in step 5, so step 4 becomes no. B = ON is determined.
[0032]
At this time, if the brake pedal 55 has been depressed or if the brake pedal 55 has been depressed strongly from the beginning, the brake switch B is turned on, so step 9 becomes yes and the process proceeds to step 10, Flag 2 = ON is determined. Here, since the flag 2 is previously turned on in step 8, step 10 becomes yes and the process proceeds to step 11, and a clutch emergency disconnection command is sent from the control unit 5 shown in FIG. The clutch 3 is quickly disconnected by the clutch actuator 4.
[0033]
As a result, when the vehicle is running with the clutch 3 connected in a low speed range where the engine speed is 1000 rpm or less, when the brake pedal 55 is pressed hard enough to turn on the brake switch B, or at first the brake is applied. Since the clutch is quickly disengaged when the brake switch B is strongly depressed so that only the switch A is turned on and then the brake switch B is turned on, the clutch 3 can be disengaged before the engine stalls. To be prevented.
[0034]
That is, in a vehicle equipped with this type of auto clutch 1, if a predetermined braking force is generated by depressing the brake pedal 55 with the clutch 3 connected during normal driving (engine speed 1000 rpm or more), The clutch 3 is disengaged by a normal clutch disengagement command (clutch disengagement command based on a decrease in engine speed, etc.) issued from 5, but with this clutch disengagement command, when the engine is running at a low engine speed of 1000 rpm or less Since the original engine speed is low, engine stall is likely to occur before the clutch 3 is disengaged.
[0035]
On the other hand, according to the present embodiment, in addition to the normal clutch disengagement command, the braking force is such that the brake switch B is turned on and the tire is locked on a low μ road when the engine speed is 1000 rpm or less. When the clutch is added, a clutch emergency disconnection command is issued from the control unit 5 to the clutch actuator 4, so that the clutch 3 can be quickly disconnected before the engine stall, which is not in time for the normal clutch disconnection command.
[0036]
Therefore, according to the present embodiment, when the engine 3 is running at a low speed with the clutch 3 connected (engine speed 1000 rpm or less), the brake pedal 55 is depressed or increased to increase the predetermined braking force (the brake switch B is turned on). In addition, when a braking force enough to lock the tire on a low μ road is generated, the clutch 3 can be disconnected before the engine stalls, and the engine stall is prevented. In particular, on a low μ road, the clutch 3 is disconnected before the tire is locked during braking, which is effective in preventing engine stall.
[0037]
By the way, in FIG. 1, if the stored engine speed ≤1000 rpm is no in step 7, that is, if the engine speed is higher than 1000 rpm, the flag 2 is turned off in step 12. If the brake pedal 55 is kept depressed after returning from the end to the start, the brake switch A is turned on, so step 1 becomes no and heads to step 4, and since flag 1 is turned off in step 5 first, step 4 If the brake pedal 55 is depressed deeply, the brake switch B is on and the process proceeds to step 10.
[0038]
Here, since the flag 2 has been turned off in step 12, the step 10 becomes no and heads to the end, and the clutch 3 is not urgently disconnected in this control flow. However, in this case, since the engine speed is higher than 1000 rpm as apparent in step 7, even if the clutch 3 is disconnected by the above-described normal clutch disconnection command (clutch disconnection command based on a decrease in engine speed, etc.) The clutch 3 can be disconnected before the engine stalls, and there is no problem. Therefore, in this case (when the engine speed is higher than 1000 rpm), the clutch emergency disconnection by this control flow is not performed.
[0039]
If the brake switch B is not turned on in step 9, the emergency clutch release by this control flow is not performed. In this case, only the brake switch A is turned on while the brake pedal 55 is kept lightly depressed. This is a state (a state in which almost no braking force is generated in the tire and the stop lamp is lit), and there is no problem because there is no concern about engine stall. When the foot is completely released from the brake pedal 55, step 1 becomes yes, flag 1 is turned on in step 2, and flag 2 is turned off in step 3.
[0040]
In the present embodiment, the operating brake pressure of the brake switch A = 0.3 kgf / cm ² , the operating brake pressure of the brake switch B = ² kgf / cm ² , and the comparative engine speed = 1000 rpm in step 7 are shown as examples. However, the present invention is not limited to these numerical values. Further, the transmission shown in FIG. 2 is not limited to this structure, and may be a normal two-shaft four-speed or five-speed transmission.
[0041]
【The invention's effect】
As described above, according to the auto clutch control device of the present invention, it is possible to prevent engine stall when the brake pedal is depressed during low engine speed travel. Further, since the clutch disengagement control is not performed when the engine is running at a high speed, it is possible to avoid a sudden decrease in driving force and a sudden deterioration in operation feeling due to the release of the engine brake, and the driver does not feel uncomfortable.
[Brief description of the drawings]
FIG. 1 is a flowchart showing a control flow of an automatic clutch control apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic view of an automatic transmission provided with the auto clutch.
FIG. 3 is an explanatory diagram showing characteristics of a brake switch of the control device.
[Explanation of symbols]
1 Auto clutch 3 Clutch 4 Clutch actuator 5 Control unit 54 Auto clutch control device 55 Brake pedal 56 Engine rotation sensor B Brake switch

Claims (1)

An automatic clutch control device that appropriately connects and disconnects a clutch by a clutch actuator when starting, shifting, and stopping,
When the brake pedal is depressed, a brake switch that is turned on at a predetermined brake pressure, an engine rotation sensor that detects the engine speed, and when the brake switch is on and the engine speed is equal to or lower than the predetermined speed, the clutch actuator A control unit that transmits a clutch emergency disconnection command,
The predetermined brake pressure at which the brake switch is turned on is set to a brake pressure that can lock the tire on the predetermined road surface μ based on the correlation between the road surface μ and the brake pressure .
The control unit stores the engine speed when another brake switch that is turned on at a predetermined brake pressure lower than the predetermined brake pressure is turned on when the brake pedal is depressed, and the engine speed is A clutch emergency disconnection command is transmitted to the clutch actuator when the brake switch that is turned on at a higher predetermined brake pressure is turned on on condition that the rotational speed is equal to or lower than a predetermined number of revolutions. Auto clutch control device.

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