JP4253882B2 - Clutch control device and recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a clutch control that performs engagement control for engaging a clutch while increasing the engine speed from a non-engaged state, for example, when starting a vehicle equipped with a continuously variable transmission with an electromagnetic powder clutch. The present invention relates to an apparatus and a recording medium.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, a clutch control device for controlling the operation of a clutch in a vehicle having an electromagnetic powder clutch in a belt type continuously variable transmission is known. In this type of clutch control device, for example, as shown in FIG. 1, the torque from the engine E is transmitted to the continuously variable transmission (CVT) 10 via the electromagnetic powder clutch 2, and the torque transmitted by the clutch 2 is Based on sensor signals such as the rotational speed and the throttle opening, adjustment is performed by a drive signal from the controller (control unit) 32 to the clutch 2.
[0003]
In the above-described clutch control device, when the vehicle starts, the controller determines a clutch drive signal based on a predetermined relationship from the engine speed, time, and the like (see Japanese Patent Publication No. 5-86489). ).
However, if the clutch has characteristic variations due to individual differences during manufacturing or changes over time, even if a drive signal is given in the same manner, the clutch engagement force will vary, resulting in overshooting of the engine speed (target function). A phenomenon in which the combined engine speed is exceeded) and undershoot (a phenomenon in which the target engagement engine speed is reduced) may occur. In such a case, there is a great influence on the fluctuation of the clutch torque and the behavior on the vehicle side, and there is a problem that a sense of incongruity due to the discontinuity of the acceleration feeling is likely to occur.
[0004]
Further, when the engine speed does not blow up sufficiently due to variations in clutch engagement force, and sudden engagement occurs due to this, there is a problem in that vehicle resonance is induced and hunting occurs.
[0005]
[Problems to be solved by the invention]
As a countermeasure against this problem, for example, in order to suppress overshoot of the engine speed, the engine speed overshoot is detected, and the relationship between the predetermined engine speed and the clutch current for controlling the clutch is increased (engaged) technique for correcting the side) to increase the force has been proposed (see JP-a-8-31 8 763 JP).
[0006]
Further, in order to suppress overshoot and undershoot, the clutch current is corrected according to the amount of change in the engine speed in an engagement control system configured by feedback of the target engagement engine speed and the actual engine speed. A technique has been proposed (see Japanese Patent Laid-Open No. 9-329161).
[0007]
However, both techniques have a problem that hunting that occurs on the vehicle side cannot always be prevented because engagement control is executed based only on the engine speed. On the other hand, as a method of suppressing the hunting of the vehicle side, there is a technique called flow clutch current of opposite phase to the vibration caused on the vehicle body (see Japanese Patent real-Open No. 4-80934).
[0008]
However, this technique has a problem that engine speed overshoot and undershoot occur because the behavior of the engine speed cannot be directly suppressed.
Therefore, in order to solve these problems, that is, to execute both overshoot and undershoot countermeasures and hunting countermeasures, it is conceivable to combine the two types of techniques described above. It becomes difficult and not always desirable.
[0009]
The present invention has been made to solve the above-described problems, and its object is to suppress all of the vehicle hunting, engine speed overshoot, and undershoot, which are problems during clutch engagement. A clutch control device and a recording medium that can be used.
[0010]
[Means for Solving the Problems and Effects of the Invention]
(1) The invention of claim 1
Clutch control for engaging and disengaging a clutch that exists between a vehicle engine and a wheel and that engages and disengages from the non-engaged state of the clutch. In the apparatus, target slip amount setting means for setting a target value of the slip amount on the driving side and the driven side of the clutch based on the information of the engine, and the actual driving side rotational speed and driven side rotation of the clutch The actual slip amount detecting means for detecting the actual slip amount of the clutch, and the slip amount control means for controlling the actual slip amount so as to match the target slip amount, and according to the state of the vehicle The target slip amount is set as an increase function with respect to the engine speed in the region below the reference engine speed, and in the region exceeding the reference engine speed, the target slip amount is Further comprising a target slip amount setting means for setting in rotation speed against) decreasing function is summarized as a clutch control apparatus according to claim.
[0011]
In the present invention, the target value of the slip amount on the driving side and the driven side of the clutch is set based on the information on the engine (for example, the actual engine speed). In this case, for example, as shown in FIG. Similarly, below the reference engine speed set according to the vehicle state (for example, the actual engine speed at the start of control), the target slip amount is set as an increase function with respect to the engine speed, and the reference engine speed is set to In the region above, it is set with a decreasing function.
[0012]
In other words, in the present invention, since the target slip amount is set as an increase function with respect to the engine speed below the reference engine speed, the problem caused by the variation in clutch engagement force, i.e., the engine speed during engagement control is reduced. Sudden engagement of the clutch due to not blowing up (insufficient rise) can be prevented. Therefore, hunting of the vehicle can be prevented.
[0013]
Further, by setting this increase function, it is possible to prevent another problem caused by the variation in the engagement force of the clutch, that is, an undershoot of the engine speed during the engagement control. This undershoot indicates that the clutch is engaged at an engine speed lower than the target engagement engine speed. However, in the present invention, the occurrence of the undershoot can be suppressed. You can prevent a sense of incongruity when driving.
[0014]
On the other hand, in a region where the engine speed exceeds the reference engine speed, the target slip amount is set as a decreasing function with respect to the engine speed, so that overshoot of the engine speed can be prevented. This overshoot indicates that the clutch is engaged at an engine speed higher than the target engagement engine speed. In the present invention, since the occurrence of the overshoot can be suppressed, It is possible to prevent a sense of incongruity when the vehicle travels due to the discontinuity of acceleration.
[0015]
That is, according to the present invention, since the engine speed behavior and the engaged side speed behavior at the time of engagement of the clutch can be set simultaneously, it is possible to suppress the occurrence of overshoot and undershoot of the engine speed, In addition, it is possible to prevent sudden engagement due to insufficient blowing of the engine speed, thereby preventing the occurrence of hunting of the vehicle.
[0016]
(2) The invention of claim 2
The gist of the clutch control device according to claim 1, wherein the reference engine speed is set based on an engine speed at the start of control.
In the present invention, the reference engine speed is set based on the engine speed at the start of control. By setting in this way, it is possible to determine whether the vehicle is starting from an idle state or starting after deceleration, and the control can be changed, effectively preventing the occurrence of overshoot and undershoot of the engine speed. In addition, it is possible to prevent the occurrence of vehicle hunting due to sudden engagement.
[0017]
(3) The invention of claim 3
The gist of the clutch control device according to claim 1, wherein the increase function is a function whose degree of increase changes during the increase.
The present invention illustrates an increase function. In the present invention, since the degree of increase changes in the middle, the occurrence of overshoot and undershoot of the engine speed can be prevented more effectively in accordance with the characteristics of the engine, etc. Hunting can be prevented.
[0018]
(4) The invention of claim 4
The gist of the clutch control device according to any one of claims 1 to 3, wherein the decreasing function is a function whose degree of reduction changes in the middle of reduction.
The present invention illustrates a decreasing function. In the present invention, since the degree of decrease changes in the middle of the process, it is possible to more effectively prevent the occurrence of overshoot and undershoot of the engine speed in accordance with the characteristics of the engine, etc. Hunting can be prevented.
[0019]
(5) The invention of claim 5
The clutch control device according to any one of claims 1 to 4, wherein the increase function and / or the decrease function is a function whose degree of change decreases in the vicinity of the reference engine speed. The gist.
[0020]
In the present invention, an increase function and a decrease function are illustrated. In the present invention, since a function whose degree of change decreases in the vicinity of the reference engine speed is used, the change from the increase function to the decrease function (or the reverse change) can be performed smoothly. Therefore, since abrupt engagement control can be suppressed, clutch torque fluctuation in the engagement control can be reduced, and quick and smooth engagement can be realized.
[0021]
(6) The invention of claim 6
The gist of the clutch control device according to any one of claims 1 to 5, wherein the slip amount control means performs control for advancing the phase of the engaged side of the clutch.
[0022]
In the present invention, the slip amount control means performs control to advance the phase on the engaged side (for example, the primary rotational speed) of the clutch. Therefore, even when hunting occurs, the slippage control means advances the phase on the engaged side. Can be suppressed.
For example, as shown in FIG. 6, when the actual slip amount varies according to the change in the primary rotation speed, the slip amount deviation that is the difference between the target slip amount and the actual slip amount also varies, and smooth engagement cannot be performed. In the present invention, for example, as shown in FIG. 5, the phase of the control signal is advanced by using, for example, a differential controller. For example, in an electromagnetic powder type clutch, when changing the magnitude of the clutch current that adjusts the engagement force, control to speed up the control timing to increase or decrease the clutch current (ie, the primary rotational speed on the engaged side of the clutch, for example) Hunting can be suppressed by performing control for advancing the phase.
[0023]
(7) The invention of claim 7
The gist of the clutch control device according to any one of claims 1 to 6, wherein the clutch engagement control is performed when the vehicle starts.
The present invention exemplifies the time when the clutch engagement control is performed. Here, the above-described engagement control is performed when the vehicle starts.
[0024]
In other words, when the vehicle is started, when the clutch is engaged, the above-described overshoot and undershoot of the engine speed and hunting due to sudden engagement are likely to occur. Implementing the control is extremely effective for a smooth start of the vehicle.
[0025]
(8) The invention of claim 8
The gist of the clutch control device according to any one of claims 1 to 7, wherein the clutch is an electromagnetic powder clutch.
The present invention exemplifies the types of clutches. Here, since the electromagnetic powder type clutch is used, the above-described engagement control can be suitably performed by controlling the current or voltage supplied to the clutch.
[0026]
Therefore, as the slip amount control means, for example, by adjusting the current value (or voltage) applied to the coil of the electromagnetic powder clutch so that the actual slip amount matches the target slip amount, the actual slip amount of the clutch is set. Means for controlling may be mentioned.
(9) The invention of claim 9
The gist of the clutch control device according to any one of claims 1 to 8, wherein a continuously variable transmission exists on the engaged side of the clutch.
[0027]
The present invention exemplifies the structure of a vehicle. Here, since the continuously variable transmission exists on the engagement side of the clutch, the engagement control described above is performed, so that the clutch is smoothly engaged, and the driving force is suitably applied to the continuously variable transmission. Transmission, thereby realizing a smooth start of the vehicle.
[0028]
(10) The invention of claim 10
A gist of a recording medium storing means for executing control by the clutch control device according to any one of claims 1 to 9.
For example, examples of the recording medium include various recording media such as an electronic control device configured as a microcomputer, a microchip, a floppy disk, a hard disk, and an optical disk.
[0029]
That is, there is no particular limitation as long as it stores a means such as a program that can execute the control of the clutch control device described above.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a clutch control device of the invention will be described in detail with reference to the drawings by way of examples (examples).
Example 1
a) First, the clutch control device of the present embodiment will be described based on the schematic configuration diagram of the continuously variable transmission unit of FIG.
[0031]
As shown in FIG. 1, a vehicle including the clutch control device of this embodiment uses an engine E as a power source, and this driving force is converted into an electromagnetic powder clutch (hereinafter also simply referred to as a clutch) 2 and a forward / reverse switching mechanism. (Not shown) is transmitted to the drive wheels via a continuously variable transmission (CVT) 10 having a primary pulley 4, a metal belt 6, and a secondary pulley 8.
[0032]
Specifically, the continuously variable transmission 10 includes a primary pulley 4 (drive pulley) on the driving side composed of the movable conical disk 12 and the fixed conical disk 14, and a secondary pulley on the driven side composed of the movable conical disk 16 and the fixed conical disk 18. 8 (driven pulley), a primary pulley cylinder 20 on the driving side, a secondary pulley cylinder 22 on the driven side, a metal belt 6 stretched between the primary pulley 4 and the secondary pulley 8, and an oil pump driven by the engine E 24, a primary hydraulic control actuator 26, a secondary hydraulic control actuator 28, a torque converter for adjusting transmission of torque from the engine E, and the like.
[0033]
The control device 30 performs various controls of the clutch 2 and the continuously variable transmission 10, and includes a control unit 32 including an electronic control circuit. The control unit 32 includes a primary rotation sensor 34 that detects the rotation speed of the primary pulley 4 (primary rotation speed NP), a secondary rotation sensor 36 that detects the rotation speed of the secondary pulley 8 (secondary rotation speed NS), and a throttle opening. It is connected to a throttle opening sensor 38 for detecting, an engine rotation sensor 40 for detecting the actual engine speed NE of the engine E, and the like.
[0034]
The control unit 32 is configured as a well-known microcomputer centering on a CPU, and is based on the detection data of the primary rotation sensor 34, the secondary rotation sensor 36, the throttle opening sensor 38, the engine rotation sensor 40, and the like. A ratio is set, and the primary hydraulic control actuator 26 is adjusted so as to be the target gear ratio, and the hydraulic pressure generated by the oil pump 24 and supplied to the primary pulley cylinder 20 is controlled.
[0035]
Further, the control unit 32 adjusts the secondary hydraulic pressure control actuator 28 so as to prevent the metal belt 6 from slipping, and controls the hydraulic pressure generated by the oil pump 24 and supplied to the secondary pulley cylinder 20.
Furthermore, the control unit 32 functions as a clutch control device that performs engagement control of the clutch 2 in order to start the vehicle smoothly, for example, when the vehicle starts. Specifically, based on each sensor signal, it is determined whether the clutch 2 is engaged or disengaged, and the amount of current (clutch current) that controls the clutch 2 is adjusted to control the clutch engaging force.
[0036]
That is, the control unit 32 calculates the target gear ratio based on the various sensor signals, and the secondary hydraulic control actuator 28 and the control unit 32 so that the actual gear ratio matches the target gear ratio without the metal belt 6 slipping. The primary hydraulic control actuator 26 is driven to perform shift control, and to perform engagement control of the clutch 2 that is a main part of the present embodiment.
[0037]
b) Next, among the controls executed by the control unit 32, the engagement control of the clutch 2 will be described with reference to FIGS.
FIG. 2 is a control block diagram of this control, FIG. 3 is a map for setting a target slip amount, and FIG. 5 shows changes due to this control.
[0038]
The engagement control of the clutch 2 is control for smoothly engaging the clutch 2 by increasing the engine speed NE from the non-engagement state of the clutch 2 when the vehicle starts, for example.
First, as shown in FIG. 2, in the target slip amount setting unit 42, as shown in FIG. 3A, based on the engine speed (actual engine speed) NE detected based on the signal of the engine speed sensor 40. From the map, the target slip amount MS, which is the optimal slip amount of the clutch 2 (the difference in rotational speed between the driving side and the driven side), is obtained.
[0039]
This map is such that the target slip amount MS is set to 0 above the target engagement engine speed NE (target meet speed MNE) that is the optimum engine speed NE when the clutch 2 is engaged. Yes, the target slip amount MS is set as an increase function at a reference engine speed KNE or less, and the target slip amount MS is set as a decrease function at a reference engine speed KNE or more. Here, the reference engine speed KNE is set to the engine speed (for example, 1400 rpm) at the start of control. The increase function is indicated by a broken line in which the degree of increase changes from large to small at a certain break point P1, and the decrease function changes from small to large to medium in two places P2 and P3. This is indicated by a broken line.
[0040]
On the other hand, the deviation between the actual primary rotational speed NP detected based on the signal from the primary rotational sensor 34 and the actual engine rotational speed NE, that is, the actual slip amount RS is obtained.
Then, a deviation between the actual slip amount RS and the target slip amount MS obtained from the above-described map, that is, a slip amount deviation ΔS is obtained and sent to the feedback control unit (FB control unit) 44.
[0041]
The FB control unit 44 performs feedback control of the actual slip amount RS by controlling the clutch current so that the slip amount deviation ΔS becomes small (for example, 0). For example, when the slip amount deviation ΔS is excessive with respect to the target slip amount MS, the clutch current is decreased so that the engagement force of the clutch 2 is reduced, and conversely, the slip amount deviation ΔS is excessively small. In this case, the clutch current is increased so that the engagement force of the clutch 2 is increased, and control is performed so that the actual slip amount RS matches the target slip amount MS.
[0042]
c) In the present embodiment, the following effects can be obtained by the control described above.
(1) In this embodiment, as shown in FIG. 3A, when the actual engine speed NE is equal to or higher than the target meet speed MNE that engages the engine side and the primary pulley side, the target slip amount MS is 0 or less. When the target rotation speed MNE is not reached, the target slip amount MS is set to a value exceeding 0.
[0043]
As a result, the actual slip amount RS becomes 0 and engages when the actual slip amount RS does not reach the target meet rotational speed MNE, or the actual slip amount RS is greater than 0 when the target meet rotational speed MNE is exceeded. Thus, it is possible to prevent an overshoot of the engine speed that occurs due to a so-called slip state.
[0044]
By performing the control described above, in this embodiment, as illustrated in FIG. 4A, the actual engine speed NE and the primary speed NP coincide with each other at the target meet speed MNE, and the actual slip The quantity RS becomes 0 and a very suitable engagement can be realized. In addition, G of FIG. 4 is a vehicle longitudinal acceleration.
[0045]
(2) In this embodiment, as shown in FIG. 3A, up to the reference engine speed KNE, the target slip amount MS is set as an increase function with respect to the actual engine speed NE, and the reference engine speed is set. For several KNE or more, the target slip amount MS is set by a decreasing function.
For example, as shown in FIG. 3B, when the target slip amount MS is set by a decreasing function, the actual engine speed NE does not blow up and the clutch 2 is suddenly engaged as illustrated in FIG. 4B. Hunting of the vehicle may occur due to the state, but by setting the target slip amount MS with an increase function and a decrease function as in this embodiment, as illustrated in FIG. Sudden engagement due to insufficient blow-up of the actual engine speed NE can be avoided, and therefore hunting of the vehicle due to sudden engagement can be prevented.
[0046]
That is, if the target slip amount MS is simply set by a decreasing function, the engagement force of the clutch 2 is sufficiently increased before the actual engine speed NE sufficiently increases, which may cause a sudden engagement. In the embodiment, the engagement force of the clutch 2 is not increased (that is, the target slip amount MS is increased) until the actual engine speed NE sufficiently increases, and after the actual engine speed NE sufficiently increases, the clutch 2 Therefore, the clutch 2 can be prevented from being suddenly engaged.
(Example 2)
Next, the second embodiment will be described, but the description of the same parts as the first embodiment will be omitted or simplified.
[0047]
In this embodiment, hunting is more effectively prevented by advancing the phase of the engaged side of the clutch 2.
As shown in FIG. 5, in the target slip amount setting unit 52, based on the actual engine speed NE detected based on the signal of the engine rotation sensor 40, the target slip amount is determined from the map as shown in FIG. Determine the quantity MS.
[0048]
On the other hand, the deviation between the actual primary rotational speed NP detected based on the signal from the primary rotational sensor 34 and the actual engine rotational speed NE, that is, the actual slip amount RS is obtained.
Then, a deviation between the target slip amount MS and the actual slip amount RS, that is, a slip amount deviation ΔS is obtained and sent to the feedback control unit (FB control unit) 54.
[0049]
The FB control unit 54 performs feedback control of the actual slip amount RS by controlling the clutch current so that the slip amount deviation ΔS becomes small (for example, 0) as in the first embodiment.
In particular, in the present embodiment, in the FB control unit 54, the differential controller 56 includes a derivative of the slip amount deviation ΔS so as to advance the phase of the slip amount deviation ΔS. The phase of the primary rotational speed NP on the engaged side can be advanced. In FIG. 5, K1 and K2 are feedback gains.
[0050]
That is, when hunting actually occurs in the vehicle, the phase of the primary rotational speed NP and the phase of the slippage deviation ΔS are the same as shown in FIG. By controlling the clutch current according to the configuration, the phase of the primary rotational speed NP can be advanced by 90 °, for example.
[0051]
As a result, the rotational fluctuation of the actual engine speed NE on the engaging side (engine E side) and the rotational fluctuation of the primary rotational speed NP on the engaged side (primary pulley 4 side) cancel each other out. Hunting is suppressed.
Needless to say, the present invention is not limited to the above-described embodiments and can be carried out in various modes without departing from the technical scope of the present invention.
[0052]
(1) For example, in the second embodiment, by configuring the feedback control system so as to calculate the actual slip amount RS by the actual engine speed NE and the primary engine speed NP obtained by adding the phase advance process, the phase of the primary engine speed May be advanced.
That is, in the second embodiment, the actual slip amount RS is the deviation between the actual engine speed NE and the primary engine speed NP, but instead of the primary engine speed NP, the primary engine speed NP to which the phase advance process is added is used. Use it.
[0053]
In this case, the control system can be configured so as to add the differential of the primary rotational speed NP to the primary rotational speed NP by removing the differential controller 56 from the FB calculation unit 56 in FIG.
(2) In the first and second embodiments, the clutch control device has been described. However, a recording medium storing means for executing control by this device is also within the scope of the present invention.
[0054]
For example, examples of the recording medium include various recording media such as an electronic control device configured as a microcomputer, a microchip, a floppy disk, a hard disk, and an optical disk.
That is, there is no particular limitation as long as it stores, for example, a program or the like that can execute the control of the transmission ratio control device for the continuously variable transmission described above.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a device configuration of a clutch control device according to a first embodiment.
FIG. 2 is a block diagram illustrating a control system of the clutch control device according to the first embodiment.
FIG. 3 shows the relationship between the actual engine speed and the target slip amount, where (a) is a graph of an example and (b) is a graph of a comparative example.
FIGS. 4A and 4B show the number of rotations and changes in G. FIG. 4A is a graph of an example, and FIG. 4B is a graph of a comparative example.
FIG. 5 is a block diagram illustrating a control system of the clutch control device according to the second embodiment.
FIG. 6 is a graph showing fluctuations in primary rotational speed and the like.
[Explanation of symbols]
E ... Engine 2 ... Electromagnetic powder clutch (clutch)
4 ... primary pulley 6 ... metal belt 8 ... secondary pulley 10 ... continuously variable transmission 30 ... control device 32 ... control unit 34 ... primary rotation sensor 36 ... secondary rotation sensor 38 ... throttle opening sensor 40 ... engine rotation sensor

Claims (10)

Clutch control for engaging and disengaging a clutch that is present between a vehicle engine and wheels and that engages and disengages by increasing the engine speed from the non-engaged state of the clutch. In the device
A target slip amount setting means for setting a target value of the slip amount on the driving side and the driven side of the clutch based on the information of the engine;
An actual slip amount detecting means for detecting an actual slip amount of the clutch from an actual drive side rotational speed and a driven side rotational speed of the clutch;
Slip amount control means for controlling the actual slip amount to match the target slip amount;
With
In the area below the reference engine speed set according to the vehicle state, the target slip amount is set with an increasing function with respect to the engine speed, and in the area exceeding the reference engine speed, it is set with a decreasing function. A clutch control device comprising target slip amount setting means.   The clutch control device according to claim 1, wherein the reference engine speed is set based on an engine speed at the start of control.   3. The clutch control device according to claim 1, wherein the increase function is a function whose degree of increase changes during the increase.   The clutch control device according to any one of claims 1 to 3, wherein the decreasing function is a function whose degree of reduction changes during the reduction.   The clutch control device according to any one of claims 1 to 4, wherein the increase function and / or the decrease function is a function whose degree of change decreases in the vicinity of the reference engine speed.   The clutch control apparatus according to any one of claims 1 to 5, wherein the slip amount control means performs control to advance a phase on the engaged side of the clutch.   The clutch control device according to any one of claims 1 to 6, wherein the timing for performing the engagement control of the clutch is when the vehicle starts.   The clutch control device according to any one of claims 1 to 7, wherein the clutch is an electromagnetic powder clutch.   The clutch control device according to any one of claims 1 to 8, wherein a continuously variable transmission exists on the engaged side of the clutch.   10. A recording medium storing means for executing control by the clutch control device according to claim 1.

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