JP2015086953A - Power transmission device and clutch drive control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission device and a clutch drive control device, capable of properly correcting clutch transmission torque following heat deformation with temperature change of a clutch even in a case where the temperature change of the clutch is relatively fast and temporary (instantaneous).SOLUTION: A clutch ECU calculates accumulated energy of friction energy occurring between a pressure plate and a clutch disk in a period from a complete release state of the clutch to a complete engagement state (step S110); calculates a deformation amount of the thickness direction of the pressure plate on the basis of the calculated accumulated energy (step S112); and defines the calculated deformation amount as a stroke correction amount, and corrects a stroke instruction value with respect to a clutch drive mechanism by using the stroke correction amount (step S114).

Description

  The present invention relates to a power transmission device and a clutch drive control device.

  As a type of the clutch drive control device, one shown in Patent Document 1 is known. As shown in FIG. 2 of Patent Document 1, in the clutch drive control device, the ECU 50 transmits between the flywheel 10a and the clutch disk 21a based on the clutch stroke that is the amount of movement of the rod 25 of the clutch actuator 23. The controlled clutch torque is controlled to a required target clutch torque (step 101). The ECU 50 detects the temperature of the clutch disk, and corrects the clutch stroke based on the detected temperature of the clutch disk (steps 200, 102, 103). Furthermore, it is disclosed that a clutch torque temperature correction coefficient that takes into account the effects of thermal expansion of the clutch disk 21a, the rod 25, the clutch lever 22, the release bearing 27, the diaphragm spring 28, the pressure plate 29, etc. with respect to the clutch temperature may be adopted. (Paragraph 0034).

JP 2008-185217 A

  In the clutch drive control device described in Patent Document 1 described above, when the temperature change of the clutch is relatively gradual, the clutch torque can be suitably controlled according to the temperature of the clutch. However, when the temperature change of the clutch is relatively fast and temporary (instantaneous), there is a problem that the clutch torque cannot be corrected following the deformation (thermal deformation) accompanying the temperature change of the clutch. .

  The present invention has been made to solve the above-described problems, and even when the temperature change of the clutch is relatively quick and temporary (instantaneous), it follows the thermal deformation accompanying the temperature change of the clutch. An object of the present invention is to provide a power transmission device and a clutch drive control device capable of appropriately correcting clutch transmission torque.

  In order to solve the above problems, the invention of the power transmission device according to claim 1 shifts and outputs the input shaft for inputting the driving force of the engine of the vehicle and the input rotation to the input shaft at a plurality of gear ratios. A transmission including a plurality of shift speeds and an output shaft that outputs the driving force of the shifted engine to the drive wheel side, a transmission drive mechanism that changes the shift speed of the transmission, and an output shaft of the engine A pressure plate that is rotationally coupled to the clutch, and a clutch disk that is rotationally coupled to the input shaft of the transmission. The pressure plate and the clutch disk are brought into contact with or separated from each other, whereby the engine output shaft and the transmission A clutch that engages or disengages with the input shaft, a clutch drive mechanism that drives the clutch, and a clutch stroke-clutch transmission that indicates the relationship between the clutch stroke and the clutch transmission torque. A storage unit that stores torque characteristics, and a control device that controls the clutch drive mechanism by instructing the clutch drive mechanism with a stroke instruction value that is a clutch stroke corresponding to a desired clutch transmission torque. The cumulative energy calculation unit that calculates the cumulative energy of the friction energy generated between the pressure plate and the clutch disk between the fully disengaged state and the fully engaged state of the clutch, and the cumulative energy calculating unit A deformation amount calculation unit that calculates a deformation amount in the thickness direction of the pressure plate from the accumulated energy, and a deformation amount calculated by the deformation amount calculation unit is set as a stroke correction amount, and a stroke instruction value for the clutch drive mechanism is corrected by the stroke correction amount. And a correction unit.

  According to this, the control device calculates the cumulative energy of the friction energy generated between the pressure plate and the clutch disk between the fully disengaged state and the fully engaged state of the clutch (cumulative energy calculating unit). Then, the deformation amount in the thickness direction of the pressure plate is calculated from the calculated accumulated energy (deformation amount calculation unit), the calculated deformation amount is set as a stroke correction amount, and the stroke instruction value for the clutch drive mechanism is set as the stroke correction amount. (Correction unit). That is, the amount of deformation of the pressure plate accompanying the temperature change of the clutch is calculated by calculating the accumulated energy from the fully disengaged state to the fully engaged state of the clutch rather than the actual measurement result of the clutch temperature. The clutch transmission torque can be corrected following the amount of deformation. Thus, even when the temperature change of the clutch is relatively fast and temporary (instantaneous), the clutch transmission torque can be appropriately corrected following the thermal deformation accompanying the temperature change of the clutch.

According to a second aspect of the present invention, there is provided the power transmission device according to the first aspect, further comprising: an engine rotational speed sensor that detects the rotational speed of the engine; and an input shaft rotational speed sensor that detects the rotational speed of the input shaft of the transmission. The accumulated energy calculation unit includes friction energy from the engine rotation speed detected by the engine rotation speed sensor, the transmission input shaft rotation speed detected by the input shaft rotation speed sensor, and the clutch transmission torque for each control cycle. And the accumulated energy is calculated based on the calculated frictional energy.
According to this, the accumulated energy can be calculated with high accuracy, and accordingly, the clutch transmission torque can be appropriately corrected following the thermal deformation accompanying the temperature change of the clutch.

According to a third aspect of the present invention, there is provided the power transmission device according to the second aspect, wherein the accumulated energy calculation unit is configured to change the engine speed detected by the engine speed sensor and the speed change detected by the input shaft speed sensor for each control cycle. The friction energy is calculated as the current friction energy from the machine input shaft rotation speed and the clutch transmission torque, and the accumulated energy is calculated by weighting the calculated current friction energy and the previously calculated previous accumulated energy.
According to this, the accumulated energy can be calculated with emphasis on the previous accumulated energy calculated last time, and even if the calculated current friction energy fluctuates unnaturally, the influence can be suppressed. it can. As a result, the accumulated energy can be calculated with high accuracy, and accordingly, the clutch transmission torque can be appropriately corrected following the thermal deformation accompanying the temperature change of the clutch.

According to a fourth aspect of the present invention, there is provided a clutch drive control device comprising: a pressure plate that is rotationally connected to an output shaft of an engine; and a clutch disk that is rotationally connected to an input shaft of a transmission. The relationship between the clutch that engages or disengages the engine output shaft and the transmission input shaft by contact or separation, the clutch drive mechanism that drives the clutch, and the clutch stroke and clutch transmission torque A storage unit that stores a clutch stroke-clutch transmission torque characteristic, and a controller that controls the clutch drive mechanism by instructing the clutch drive mechanism a stroke instruction value that is a clutch stroke corresponding to a desired clutch transmission torque; Applied to the clutch drive device, the control device is in the fully released state of the clutch From the accumulated energy calculated by the accumulated energy calculating unit to calculate the accumulated energy of the friction energy generated between the pressure plate and the clutch disk. A deformation amount calculation unit that calculates a deformation amount in the thickness direction; and a correction unit that uses the deformation amount calculated by the deformation amount calculation unit as a stroke correction amount and corrects a stroke instruction value for the clutch drive mechanism with the stroke correction amount. That is.
According to this, the same operation and effect as the invention according to claim 1 described above can be obtained.

1 is a schematic diagram showing an outline of an embodiment of a vehicle including a power transmission device and a clutch drive control device according to the present invention. It is sectional drawing which shows the clutch periphery shown in FIG. 1, and the engagement state of a clutch drive mechanism. FIG. 2 is a cross-sectional view showing a released state of a clutch periphery and a clutch drive mechanism shown in FIG. 1. It is a figure which shows the clutch stroke-clutch transmission torque characteristic memorize | stored in the memory | storage part shown in FIG. It is a figure which shows the relationship between the accumulated energy memorize | stored in the memory | storage part shown in FIG. 1, and deformation amount (stroke correction amount). 2 is a flowchart of a control program executed by a clutch ECU shown in FIG. It is sectional drawing for demonstrating the thermal curvature of the pressure plate shown to FIG. It is a time chart for demonstrating the effect when this invention is not applied. It is a time chart for demonstrating the effect when this invention is applied. It is a figure for demonstrating that there is a correlation in the relationship between accumulated energy and deformation.

Hereinafter, an embodiment of a vehicle to which a power transmission device and a clutch drive control device according to the present invention are applied will be described with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of the vehicle.
As shown in FIG. 1, the vehicle M includes an engine 11, a clutch 21, a clutch drive mechanism 22, a transmission 12, a propeller shaft 13, a differential device 14, driving wheels (left and right rear wheels) Wrl and Wrr, and driven wheels (steering wheels). ; Left and right front wheels) Wfl, Wfr.

  The engine 11 is operated by combustion of fuel and generates driving force. The driving force of the engine 11 is configured to be transmitted to the drive wheels Wrl and Wrr via the clutch 21, the transmission 12, the propeller shaft 13, and the differential device 14. An intake passage 11a of the engine 11 is provided with a throttle valve 11b that is opened and closed in accordance with an operation amount of an accelerator pedal 15 (described later). The throttle valve 11b is opened and closed by a throttle motor 11c according to an instruction from an engine ECU 31 (described later). The opening of the throttle valve 11b (hereinafter referred to as the throttle opening) is detected by a throttle opening sensor 11d, and the detection result is output to the engine ECU 31. Further, the engine 11 is provided with a rotation speed sensor 11e. The rotational speed sensor 11e detects the rotational speed of the crankshaft of the engine 11 (that is, the engine rotational speed), and outputs the detected value to the engine ECU 31.

  As shown in FIG. 1, the clutch 21 is provided between the engine 11 and the transmission 12, interrupts power transmission between the engine 11 and the transmission 12 when released, and enables power transmission when engaged. It will be. The clutch drive mechanism 22 is operated by electricity or hydraulic pressure to drive the clutch 21 by hydraulic pressure or electric power, and engages or releases the clutch 21.

Further, the clutch 21 and the clutch drive mechanism 22 will be described in detail with reference to FIG.
The clutch 21 is a dry / single plate type hydraulically operated friction clutch. The clutch 21 is a so-called diaphragm spring type clutch. As shown in FIG. 2, the clutch 21 (40) includes a clutch disk 41, a pressure plate 42, a diaphragm spring 43, a clutch cover 44, a hydraulic direct cylinder (concentric slave cylinder) 45, and the like.

  The pressure plate 42, the diaphragm spring 43, and the clutch cover 44 are integrally attached to the flywheel 11g of the engine 11. The flywheel 11g is formed of cast iron or the like, has a thick disk shape, has a mass that maintains inertia, and is coaxially fixed to the output shaft 11f of the engine 11.

  The outer peripheral edge of the substantially cylindrical clutch cover 44 is fixed to the outer peripheral edge of the flywheel 11g opposite to the engine 11. A substantially disc-shaped clutch disk 41 is disposed inside the clutch cover 44 adjacent to the flywheel 11g. The clutch disc 41 includes a steel plate clutch plate 41a and a clutch facing 41b. On the other hand, the central portion (boss portion) of the clutch plate 41a is splined to the input shaft 12a of the automatic transmission 12, and the clutch disk 41 rotates integrally with the input shaft 12a. Clutch facings 41b formed in an annular shape with a friction material are fixed to both surfaces of the outer peripheral edge of the clutch disc 41, respectively.

  The pressure plate 42 is provided adjacent to the clutch disk 41 so as to be movable along the axial direction (the axial direction of the input shaft 12a). The pressure plate 42 is made of iron and has a substantially annular shape. The pressure plate 42 includes an annular disc portion 42a and a connection portion 42b. The annular disk portion 42a has a friction surface that comes into contact with and friction with the clutch facing 41b. A connecting portion 42b is provided on the back surface of the annular disc portion 42a opposite to the friction surface. The connecting portion 42b is connected to the outer peripheral edge of the diaphragm spring 43.

  The diaphragm spring 43 is a spring that is formed by press-molding with a spring steel plate and has a disk shape. The diaphragm spring 43 also functions as a coil spring type release lever. A diaphragm spring 43 is attached to an attachment portion 44 a of the clutch cover 44 between the outer peripheral edge portion and the inner peripheral edge portion (center portion). The diaphragm spring 43 is supported by the mounting portion 44a as a fulcrum. The outer peripheral edge of the diaphragm spring 43 urges the pressure plate 42 toward the clutch disc 41 with the mounting portion 44a as a fulcrum. When the central portion of the diaphragm spring 43 is pushed by the hydraulic direct cylinder 45, the diaphragm spring 43 warps with the mounting portion 44a as a fulcrum.

The hydraulic direct cylinder 45 includes an annular cylinder 45b having an annular pressure chamber 45a and an annular piston 45c that slides inside the cylinder 45b. The pressure chamber 45a communicates with the pressure chamber 22b1 of the clutch master cylinder 22b2.
A release bearing 46 is provided between the piston 45c and the diaphragm spring 43 to allow the axial rotation of the piston 45c and the diaphragm spring 43 while allowing relative rotation between the piston 45c and the diaphragm spring 43. The release bearing 46 transmits a clutch operating force from the piston 45c to the diaphragm spring 43 and a spring reaction force from the diaphragm spring 43 to the piston 45c.

The clutch drive mechanism 22 operates the hydraulic direct cylinder 45, and includes an electric mechanism 22a1, an output rod 22a2, a hydraulic mechanism 22b, a stroke sensor 22c, and the like.
The electric mechanism 22a1 includes an electric motor, a speed reduction mechanism (both not shown), and the like, and reciprocates the output rod 22a2 along the axial direction and fixes the positioning. The hydraulic mechanism 22b includes a clutch master cylinder 22b2 having a pressure chamber 22b1, and a piston 22b3 that slides in the clutch master cylinder 22b2. The stroke sensor 22c detects a clutch stroke that is an operation amount of the clutch drive mechanism 22 (an operation amount of the output rod 22a2), and outputs the detected clutch stroke to the clutch ECU 33.

  In the clutch 40 in the connected state (completely engaged state) as shown in FIG. 2, when the electric mechanism 22a1 of the clutch drive mechanism 22 is driven and the output rod 22a2 is moved to the left (FIG. 2), the hydraulic pressure In the mechanism 22b, the piston 22b3 is moved to the left, and hydraulic pressure is generated in the pressure chamber 22b1. The generated hydraulic pressure is transmitted to the pressure chamber 45a of the hydraulic direct cylinder 45, and the piston 45c is moved to the left. When the piston 45c presses the central portion of the diaphragm spring 43 to the left via the release bearing 46, the diaphragm spring 43 warps around the mounting portion 44a (see FIG. 3). Along with this, the pressure plate 42 is driven rightward and is separated from the clutch disk 41. As a result, the clutch 40 is in a disconnected state for releasing the connection.

  On the other hand, in the clutch 40 in the disconnected state (completely released state) as shown in FIG. 3, when the electric mechanism 22a1 of the clutch drive mechanism 22 is driven and the output rod 22a2 is moved to the right (FIG. 3), In the hydraulic mechanism 22b, the piston 22b3 is moved (returned) to the right by a return spring (not shown). Therefore, the hydraulic pressure in the pressure chamber 22b1 decreases and finally the hydraulic pressure is released. As a result, the hydraulic pressure in the pressure chamber 45a of the hydraulic direct cylinder 45 communicating with the pressure chamber 22b1 is also reduced and finally released, and the piston 45c is moved to the right. By restoring the diaphragm spring 43 that has warped, the release bearing 46 is pushed to the right, and the pressure plate 42 is driven to the left to approach the clutch disc 41. Eventually, the pressure plate 42 sandwiches and presses the clutch disc 41 between the pressure wheel 42 and the flywheel 11g, and changes the pressure load of the clutch facing 41b of the clutch disc 41 that slides and rotates with respect to the flywheel 11g. it can.

  The transmission 12 is provided between the clutch 21 and the differential device 14. The transmission 12 is shifted with an input shaft 12a for inputting the driving force of the engine 11 and a transmission mechanism 12b having a plurality of shift stages for shifting and outputting an input rotation to the input shaft 12a at a plurality of gear ratios. And an output shaft 12c for outputting the driving force of the engine 11 to the driving wheel side. In this embodiment, the transmission 12 is an automated manual transmission (AMT). The transmission 12 is a transmission that is automatically shifted other than a torque converter type automatic transmission, such as a dual clutch transmission or a semi-automatic transmission.

  Furthermore, the transmission 12 includes a rotation speed sensor 12a1 (input shaft rotation speed sensor) that detects the rotation speed of the input shaft 12a. The detected value is output to the engine ECU 31. The transmission 12 also includes a transmission drive mechanism 12d that changes the gear position of the transmission mechanism 12b. The output shaft 12 c of the transmission 12 is connected to the propeller shaft 13.

  In the vehicle M, the engine 11 is electrically connected to the engine ECU 31, the transmission 12 is electrically connected to the automatic transmission ECU 32, and the clutch drive mechanism 22 is connected to the clutch ECU 33. The engine ECU 31, the automatic transmission ECU 32, and the clutch ECU 33 are communicably connected to each other by a CAN or the like. The engine ECU 31 is an ECU (electronic control unit: electronic control unit; the same applies in this specification) that controls the engine 11.

The engine ECU 31 is electrically connected to an accelerator opening sensor 15a that is attached to an accelerator pedal 15 that adjusts the output of the engine 11 and detects the opening thereof. The detection result of the accelerator opening sensor 15a is output to the engine ECU 31. The engine ECU 31 adjusts the opening degree of the throttle valve 11b according to the opening degree of the accelerator pedal 15.
The automatic transmission ECU 32 is an ECU that controls the transmission 12, and transmits a control command to the transmission drive mechanism 12d to establish each gear stage.

  The clutch ECU 33 is an ECU that controls the clutch 21, and controls the clutch 21 to be engaged or released by transmitting a control command to the electric mechanism 22 a 1 of the clutch drive mechanism 22. Specifically, the clutch ECU 33 refers to a clutch stroke-clutch transmission torque characteristic (hereinafter referred to as a clutch torque characteristic) shown in FIG. 4 in order to generate a desired clutch transmission torque in the clutch 21. A clutch stroke corresponding to the clutch transmission torque is acquired, and the clutch drive mechanism 22 is controlled so as to be the acquired clutch stroke.

  A storage unit 33 a is connected to the clutch ECU 33. The storage unit 33a stores a clutch torque characteristic indicating the relationship between the stroke of the clutch 21 and the transmission torque of the clutch 21. As shown in FIG. 4, the clutch torque characteristic is set so that the clutch transmission torque is zero when the clutch stroke is zero, and the clutch transmission torque increases as the clutch stroke increases. That is, when the clutch 21 is in the released state, the clutch stroke is 0, and the clutch stroke is set to increase as the clutch 21 operates in the engaged state.

  The storage unit 33a stores a map (see FIG. 5) showing the relationship between the accumulated energy Ea and the deformation amount (displacement amount) Δt in the thickness direction of the pressure plate 42. As shown in FIG. 5, the relationship between the accumulated energy Ea and the deformation amount Δt is in a proportional relationship, and the deformation amount Δt increases as the accumulated energy Ea increases.

  Each of the ECUs 31 to 33 includes a CPU unit that executes arithmetic processing, a storage unit such as a ROM or RAM that stores programs and various maps, and an input / output unit for exchanging information. ing. The “power transmission device” of the present application includes a transmission 12, a transmission drive mechanism 12d, a clutch 21, a clutch drive mechanism 22, a storage unit 33a, and a control device 33. The “power transmission device control device” and “clutch drive braking device” of the present application are configured only by the clutch ECU 33, but are configured by the clutch ECU 33 and the engine ECU 31 (or the automatic transmission ECU 32). Also good.

Next, an example of operation | movement of the power transmission device comprised in this way is demonstrated with reference to the flowchart shown in FIG.
The clutch ECU 33 repeatedly executes a program corresponding to the above flowchart every predetermined short time (control cycle time) when a start switch (or an ignition switch) (not shown) is in an ON state. Note that an engaging flag F described later is initially set to OFF. The engaged flag F indicates that the clutch 21 is engaged when it is on, and that it is not engaged when it is off.

  Each time the clutch ECU 33 starts executing the program in step S100 of FIG. 6, it determines in step S102 whether or not the engaging flag F is OFF. If the clutch ECU 33 is not engaged, it determines “YES” in step S102 and advances the program to step S104. On the other hand, if the clutch ECU 33 is engaged, it determines “NO” in step S102 and advances the program to step S108.

  If the clutch ECU 33 satisfies the conditions for starting the engagement process of the clutch 21, for example, if the clutch 21 is engaged when the vehicle M starts or shifts, in step S <b> 104. It determines with "YES", a program is advanced to step S106, and an engaging flag is set to ON. On the other hand, when the condition for starting the engagement process of the clutch 21 is not satisfied, the clutch ECU 33 determines “NO” in step S104, advances the program to step S122, and temporarily ends this flowchart.

  In step S108, the clutch ECU 33 calculates a target clutch transmission torque and a target stroke. The clutch ECU 33 calculates a target clutch transmission torque suitable for clutch control corresponding to the vehicle state. The target stroke is a control target value of the clutch stroke, that is, an instruction value (stroke instruction value). The target stroke is a clutch stroke corresponding to the target clutch transmission torque calculated using the clutch torque characteristic shown in FIG.

In step S110, the clutch ECU 33 calculates the accumulated energy Ea (accumulated energy calculation unit). This accumulated energy Ea is the accumulated energy of the friction energy Eb generated between the pressure plate 42 and the clutch disk 41 during the period from the fully released state to the fully engaged state of the clutch 21.
Specifically, the current friction energy Eb (n) calculated in the current control cycle is calculated first. The friction energy Eb (n) this time is calculated from the engine rotational speed Ne, the input rotational speed Ni that is the rotational speed of the input shaft 12a of the transmission 12, and the estimated clutch transmission torque Tc, as shown in the following equation (1).

(Equation 1)
Eb (n) = (Ne (n) −Ni (n)) × Tc (n) × TM1
The engine rotational speed Ne (n) and the input rotational speed Ni (n) are rotational speeds detected by the rotational speed sensors 11e and 12a1 in the current control cycle, respectively. These detections are performed in the process of step S110. TM1 is a control cycle time.

  Further, the current estimated clutch transmission torque Tc (n) calculated in the current control cycle is calculated (estimated) from the engine torque Te that is the torque of the engine 11 and the inertia torque Ie of the engine 11 as shown in the following formula 2. ) This is because the clutch transmission torque is the result of canceling the engine rotational speed by the amount that has been increased (or decreased).

(Equation 2)
Tc = Te (n) -Ie * (Ne (n) -Ne (n-1))
= Te (n) -Ie × α (n)
Here, the engine torque Te (n) obtained this time may be obtained from the engine ECU 31, and the accelerator opening (or throttle opening), the engine speed Ne (n), and the accelerator opening May be calculated from a map showing the correlation between the engine rotational speed Ne (n) and the engine torque. Ne (n) is the rotational speed of the engine 11 detected and acquired in the current control cycle, and Ne (n-1) is the rotational speed of the engine 11 detected and acquired in the previous control cycle. Α (n) is the rotational acceleration of the engine 11. The inertia torque Ie is a design value and is stored in advance in the storage unit 33a and the like.

  Next, the clutch ECU 33 calculates the current cumulative energy Ea (n) from the current friction energy Eb (n) and the previous cumulative energy Ea (n−1) calculated in the previous control cycle. Specifically, the clutch ECU 33 calculates the current cumulative energy Ea (n) by weighting the current friction energy Eb (n) and the previous cumulative energy Ea (n−1). For example, the current accumulated energy Ea (n) is expressed by the following formula 3.

(Equation 3)
Ea (n) = Ea (n−1) × c1 + Eb (n) × c2
Here, c1 and c2 are weighting coefficients, and c1 + c2 = 1 and c1> c2. For example, c1 = 0.99 and c2 = 0.01 are set. c1 and c2 are preferably set in consideration of heat transfer in the thickness direction of the pressure plate 42 (annular disk portion 42a).

  In step S112, the clutch ECU 33 calculates a deformation amount Δt in the thickness direction of the pressure plate 42 from the current accumulated energy Ea (n) calculated in step S110 (deformation amount calculation unit). Specifically, the clutch ECU 33 obtains the current cumulative energy from the current cumulative energy Ea (n) and the map showing the correlation between the cumulative energy Ea and the deformation amount Δt in the thickness direction of the pressure plate 42 shown in FIG. A deformation amount Δt corresponding to Ea (n) is calculated.

  In step S114, the clutch ECU 33 uses the deformation amount Δt calculated in step S112 as the stroke correction amount ΔS, and corrects the stroke instruction value (target stroke) for the clutch drive mechanism 22 with the stroke correction amount ΔS (correction unit). Specifically, the clutch ECU 33 calculates a corrected target stroke by subtracting the stroke correction amount ΔS from the target stroke previously calculated in step S108. This corrected target stroke is the target stroke corrected by the stroke correction amount ΔS.

  In step S116, the clutch ECU 33 instructs the clutch drive mechanism 22 to correct the corrected target stroke (corrected stroke instruction value) and controls the clutch drive mechanism 22. As a result, the clutch 21 can generate the target clutch transmission torque previously calculated in step S108.

  The clutch ECU 33 continues to determine “NO” in step S118 until there is an instruction to end the engagement process of the clutch 21, advances the program to step S122, and continues the engagement process of the clutch 21 described above. On the other hand, when there is an instruction to end the engagement process of the clutch 21, the clutch ECU 33 determines “YES” in step S 118, ends the engagement process of the clutch 21 and sets the engaging flag F to OFF. (Step S120). Thereafter, the clutch ECU 33 advances the program to step S122 and once ends the program.

  When the present invention is not applied, the rotational speed of the engine 11 decreases when the clutch is engaged when the vehicle starts (especially on an uphill road). The inventor has found that this reason is as follows. In other words, the pressure plate 42 undergoes thermal warping, and the clutch transmission torque increases from the target clutch transmission torque. As a result, when the clutch is engaged when the vehicle starts (especially on an uphill road), Increase more. Thereby, the rotational speed of the engine 11 decreases.

  This will be described in detail below. Friction heat is generated between the clutch facing 41b of the clutch disc 41 and the friction surface of the annular disk portion 42a of the pressure plate 42 during engagement of the clutch 21, particularly during starting (uphill road) or shifting. Occur. At this time, a temperature difference occurs between the friction surface and the back surface of the annular disk portion 42a in a short time. In particular, at the beginning of engagement, the temperature difference is significant. Thereafter, the temperature difference decreases. Due to the temperature difference generated between the friction surface and the back surface, the annular disk portion 42a undergoes thermal warping as shown in FIG.

  Specifically, the inner peripheral side of the annular disc portion 42a is deformed to the clutch disc 41 side, and the outer peripheral side is deformed to the diaphragm spring 43 side. As a result, the outer peripheral side of the annular disc portion 42 a is separated from the clutch disk 41, and only the inner peripheral side is in contact with the clutch disk 41. Compared with the case of full contact (left side in FIG. 7), the radius (effective working radius) of the contact portion becomes smaller (right side in FIG. 7), so the clutch transmission torque decreases. In addition, the effective action radius in the case of contact with the entire surface is the center in the radial direction (left side in FIG. 7).

  On the other hand, the pressure plate 42 is deformed so that the inner peripheral edge of the annular disk portion 42a moves toward the clutch disk 41 with the support point supported by the diaphragm spring 43 as a fulcrum. The displacement amount of the inner peripheral edge of the annular disc portion 42a at this time is the deformation amount Δt in the thickness direction of the pressure plate 42. As described above, although the effective working radius is reduced and the clutch transmission torque is reduced, the stroke is increased by the amount of deformation Δt, and the clutch transmission torque that increases as the stroke increases is increased. That is, even if the clutch 21 is controlled to have a target stroke, the actual clutch transmission torque increases because the stroke actually increases by the deformation amount Δt from the target stroke. As a result, as shown in FIG. 8, the increased actual clutch transmission torque becomes larger than the engine torque, so that the rotational speed of the engine 11 decreases.

  The time chart shown in FIG. 8 will be described. When the accelerator pedal is depressed at time t1, the engine speed starts to increase and the engagement of the clutch 21 is started. The engine speed once exceeds the required engine speed corresponding to the driving force required to travel on the uphill road. However, between the time t2 and the time t3, the clutch transmission torque becomes larger than the engine torque, so the rotational speed of the engine 11 decreases and falls below the required engine rotational speed, and the rotational speed of the input shaft 12a of the transmission 12 Decrease. As a result, the vehicle decelerates and cannot climb the uphill road.

  On the other hand, when the present invention is applied, the rotational speed of the engine 11 does not decrease when the clutch is engaged when the vehicle starts (especially on an uphill road). This is due to the following reason. As described above, the annular disk portion 42a is warped by frictional heat generated when the clutch 21 is engaged (see FIG. 7). However, the deformation amount Δt due to thermal warpage is calculated (estimated), and the target stroke is corrected using the deformation amount Δt as the stroke correction amount ΔS. That is, the post-correction target stroke is calculated by subtracting the stroke correction amount ΔS from the target stroke previously calculated in step S108. As a result, the clutch 21 is controlled so that the corrected target stroke is obtained. Therefore, even if the annular disk portion 42a undergoes thermal warping, the stroke corresponding to the deformation amount Δt is subtracted in advance, so that the desired stroke is obtained. (Target stroke) As a result, a desired clutch transmission torque (target clutch transmission torque) can be obtained.

  That is, when the target clutch transmission torque (target stroke) of the clutch 21 is calculated in advance (step S108), the clutch transmission torque (stroke) actually increases by the deformation amount Δt, that is, the actual clutch transmission torque. Can be controlled to the target clutch transmission torque (the clutch transmission torque calculated in step S108). As a result, as shown in FIG. 9, the actual clutch transmission torque can be suppressed from becoming larger than the engine torque, so that the rotational speed of the engine 11 increases without decreasing.

The time chart shown in FIG. 9 will be described. When the accelerator pedal is depressed at time t11, the engine speed starts to increase and the engagement of the clutch 21 is started. At time t12, the engine rotation speed exceeds the required engine rotation speed corresponding to the driving force necessary for traveling on the uphill road. After time t2, the actual clutch transmission torque does not become larger than the engine torque and remains small. Therefore, the rotational speed of the engine 11 does not decrease and exceeds the required engine rotational speed, and the input shaft 12a of the transmission 12 The rotational speed increases without decreasing. As a result, the vehicle can accelerate and climb the uphill road without decelerating.
It should be noted that the target clutch transmission torque when the present invention is applied is a value smaller than the target clutch transmission torque when the present invention is not applied by an amount corresponding to the deformation amount Δt.

Furthermore, the inventors of the present application have found that there is a correlation in the relationship between the cumulative energy Ea and the deformation amount Δt. This correlation will be described in detail. As shown in FIG. 10, the actual clutch transmission torque (actual Tc) is larger than the target clutch transmission torque (Tc). That is, the actual clutch stroke (stroke (actual Tc)) is larger than the target clutch stroke (stroke (Tc)). The difference between the actual clutch stroke and the target clutch stroke is the above-described deformation amount Δt. At this time, as shown in FIG. 10, it is clear that there is a correlation between the accumulated energy Ea calculated in the same manner as described above and the deformation amount Δt.
The relationship between the cumulative energy Ea and the deformation amount Δt may be created from data acquired using an actual vehicle. That is, the difference between the actual clutch stroke and the target clutch stroke may be calculated, and the calculated difference and the accumulated energy calculated at that time may be mapped and created.

  As is clear from the above description, the power transmission device according to the present embodiment changes the input shaft 12a for inputting the driving force of the engine 11 of the vehicle M and the input rotation to the input shaft 12a at a plurality of gear ratios. A transmission 12 having a plurality of shift speeds to be output and an output shaft 12c for outputting the driving force of the engine 11 that has been shifted to the drive wheel side, and a transmission drive mechanism for changing the shift speed of the transmission 12 12d, a pressure plate 42 that is rotationally connected to the output shaft 11f of the engine 11, and a clutch disk 41 that is rotationally connected to the input shaft 12a of the transmission 12, and the pressure plate 42 and the clutch disk 41 are in contact with each other. Alternatively, by separating, the clutch 21 that engages or releases the output shaft 11f of the engine 11 and the input shaft 12a of the transmission 12 and the clutch 21 are driven. The clutch drive mechanism 22, the storage unit 33a that stores the clutch stroke-clutch transmission torque characteristic indicating the relationship between the stroke of the clutch 21 and the transmission torque of the clutch 21, and the clutch drive mechanism 22 correspond to the desired clutch transmission torque. A control device (clutch ECU 33) that controls a clutch drive mechanism 22 by instructing a stroke instruction value that is a clutch stroke, and the clutch ECU 33 is in a state from a fully disengaged state to a fully engaged state of the clutch 21. A cumulative energy calculation unit (step S110) that calculates the cumulative energy of friction energy generated between the pressure plate 42 and the clutch disk 41, and the thickness direction of the pressure plate 42 from the cumulative energy calculated by the cumulative energy calculation unit. Deformation amount Δt A deformation amount calculation unit (step S112) that calculates the amount of deformation, and a correction unit (step S112) that uses the deformation amount Δt calculated by the deformation amount calculation unit as the stroke correction amount ΔS and corrects the stroke instruction value for the clutch drive mechanism 22 by the stroke correction amount ΔS ( Step S114).

  According to this, the clutch ECU 33 calculates the cumulative energy of the frictional energy generated between the pressure plate 42 and the clutch disk 41 during the period from the fully released state to the fully engaged state of the clutch 21 (cumulative energy). A calculation unit) calculates a deformation amount Δt in the thickness direction of the pressure plate 42 from the calculated accumulated energy (deformation amount calculation unit), and uses the calculated deformation amount Δt as a stroke correction amount ΔS, and the clutch drive mechanism 22 Is corrected by the stroke correction amount ΔS (correction unit). That is, the amount of deformation of the pressure plate 42 due to the temperature change of the clutch 21 is calculated by calculating the accumulated energy from the fully disengaged state to the fully engaged state of the clutch 21 instead of the measurement result of the actually generated clutch temperature. Δt can be calculated, and the clutch transmission torque can be corrected following the amount of deformation Δt. Thus, even when the temperature change of the clutch 21 is relatively fast and temporary (instantaneous), the clutch transmission torque can be appropriately corrected following the thermal deformation accompanying the temperature change of the clutch 21. it can.

The power transmission device according to the present embodiment further includes a rotation speed sensor 11e that detects the rotation speed of the engine 11 and a rotation speed sensor 12a1 that detects the rotation speed of the input shaft 12a of the transmission 12, and calculates cumulative energy. The unit (step S110) obtains friction energy from the engine rotational speed detected by the rotational speed sensor 11e, the transmission input shaft rotational speed detected by the rotational speed sensor 12a1, and the transmission torque of the clutch 21 for each control cycle. Calculate the accumulated energy based on the calculated frictional energy.
According to this, the accumulated energy can be calculated with high accuracy, and accordingly, the clutch transmission torque can be appropriately corrected following the thermal deformation accompanying the temperature change of the clutch 21.

Further, in the power transmission device according to the present embodiment, the accumulated energy calculation unit (step S110) performs the engine rotation speed detected by the rotation speed sensor 11e and the transmission input shaft detected by the rotation speed sensor 12a1 for each control cycle. The frictional energy is calculated as the current frictional energy from the rotational speed and the transmission torque of the clutch 21, and the cumulative energy is calculated by weighting the calculated current frictional energy and the previously calculated previous cumulative energy.
According to this, the accumulated energy can be calculated with emphasis on the previous accumulated energy calculated last time, and even if the calculated current friction energy fluctuates unnaturally, the influence can be suppressed. it can. As a result, the accumulated energy can be calculated with high accuracy, and accordingly, the clutch transmission torque can be appropriately corrected following the thermal deformation accompanying the temperature change of the clutch 21.

The clutch drive control device according to the present embodiment includes a pressure plate 42 that is rotationally connected to the output shaft 11 f of the engine 11, and a clutch disk 41 that is rotationally connected to the input shaft 12 a of the transmission 12. A clutch 21 that engages or disengages the output shaft 11f of the engine 11 and the input shaft 12a of the transmission 12 by making contact with or separating from the clutch disk 41, and a clutch drive mechanism 22 that drives the clutch 21. The storage portion 33a that stores the clutch stroke-clutch transmission torque characteristic indicating the relationship between the stroke of the clutch 21 and the transmission torque of the clutch 21, and the stroke that is the clutch stroke corresponding to the desired clutch transmission torque. Control the clutch drive mechanism 22 by indicating the command value The clutch ECU 33 is provided between the pressure plate 42 and the clutch disk 41 during the period from the fully disengaged state to the fully engaged state of the clutch 21. A cumulative energy calculation unit (step S110) for calculating the cumulative energy of the frictional energy generated in this manner, and a deformation amount calculation unit for calculating the deformation amount Δt in the thickness direction of the pressure plate 42 from the cumulative energy calculated by the cumulative energy calculation unit ( And a correction unit (step S114) for correcting the stroke instruction value for the clutch drive mechanism 22 by the stroke correction amount ΔS, using the deformation amount Δt calculated by the deformation amount calculation unit as the stroke correction amount ΔS. That is.
According to this, the same operation and effect as the power transmission device concerning this embodiment mentioned above can be acquired.

In the above-described embodiment, the present invention is applied to a vehicle in which only the engine 11 is mounted as a drive source, but can also be applied to a hybrid vehicle. In this case, a motor generator 23 provided between the clutch 21 and the drive wheels Wrr and Wrl and capable of outputting a drive force to the drive wheels Wrr and Wrl may be further provided.
Further, the clutch drive mechanism 22 may be driven only by electric power without intervention of hydraulic pressure.

DESCRIPTION OF SYMBOLS 11 ... Engine, 11b ... Throttle valve, 11e ... Rotational speed sensor (engine rotational speed sensor), 12 ... Automatic transmission, 12a ... Input shaft, 12a1 ... Rotational speed sensor (input shaft rotational speed sensor), 12d ... Transmission transmission Mechanism: 13 ... Propeller shaft, 14 ... Differential device, 15 ... Accelerator pedal, 15a ... Accelerator opening sensor, 21, 40 ... Clutch, 22 ... Clutch drive mechanism, 22c ... Stroke sensor, 23 ... Motor generator, 31 ... Engine ECU 32 ... Automatic transmission ECU, 33 ... Clutch ECU (control device, cumulative energy calculation unit, deformation amount calculation unit, correction unit), 33a ... Storage unit, 41 ... Clutch disk, 42 ... Pressure plate, M ... Vehicle, Wrl , Wrr: Drive wheels (left and right rear wheels), Wfl, Wfr ... driven wheels (left and right) Wheel).

Claims (4)

An input shaft for inputting the driving force of the engine of the vehicle, a plurality of shift stages for shifting and outputting the input rotation to the input shaft at a plurality of gear ratios, and the shifted driving force of the engine on the drive wheel side A transmission having an output shaft for outputting;
A transmission drive mechanism for changing the gear position of the transmission;
A pressure plate that is rotationally connected to the output shaft of the engine, and a clutch disk that is rotationally connected to the input shaft of the transmission, and the pressure plate and the clutch disk are brought into contact with or separated from each other. A clutch for engaging or releasing the output shaft of the engine and the input shaft of the transmission;
A clutch drive mechanism for driving the clutch;
A storage unit for storing a clutch stroke-clutch transmission torque characteristic indicating a relationship between a stroke of the clutch and a transmission torque of the clutch;
A control device for instructing the clutch drive mechanism with a stroke instruction value that is a clutch stroke corresponding to a desired clutch transmission torque, and controlling the clutch drive mechanism;
The controller is
A cumulative energy calculation unit for calculating a cumulative energy of friction energy generated between the pressure plate and the clutch disk during a period from a fully disengaged state to a fully engaged state of the clutch;
A deformation amount calculation unit that calculates a deformation amount in the thickness direction of the pressure plate from the accumulated energy calculated by the cumulative energy calculation unit;
A correction unit that uses the deformation amount calculated by the deformation amount calculation unit as a stroke correction amount, and corrects the stroke instruction value for the clutch drive mechanism by the stroke correction amount;
Power transmission device with An engine speed sensor for detecting the engine speed;
An input shaft rotation speed sensor that detects a rotation speed of the input shaft of the transmission, and
The accumulated energy calculation unit, for each control cycle, from the engine rotation speed detected by the engine rotation speed sensor, the transmission input shaft rotation speed detected by the input shaft rotation speed sensor, and the transmission torque of the clutch, The power transmission device according to claim 1, wherein the friction energy is calculated, and the accumulated energy is calculated based on the calculated friction energy. The accumulated energy calculation unit, for each control cycle, from the engine rotation speed detected by the engine rotation speed sensor, the transmission input shaft rotation speed detected by the input shaft rotation speed sensor, and the transmission torque of the clutch, Calculate the friction energy as friction energy this time,
The power transmission device according to claim 2, wherein the accumulated energy is calculated by weighting the calculated current friction energy and the previously calculated previous accumulated energy. A pressure plate that is rotationally connected to the output shaft of the engine, and a clutch disk that is rotationally connected to the input shaft of the transmission, and the pressure plate and the clutch disk are brought into contact with or separated from each other, A clutch for engaging or releasing the output shaft of the engine and the input shaft of the transmission;
A clutch drive mechanism for driving the clutch;
A storage unit for storing a clutch stroke-clutch transmission torque characteristic indicating a relationship between a stroke of the clutch and a transmission torque of the clutch;
The clutch drive mechanism is applied to a clutch drive device that includes a control device that controls the clutch drive mechanism by instructing a stroke instruction value that is a clutch stroke corresponding to a desired clutch transmission torque.
The controller is
A cumulative energy calculation unit for calculating a cumulative energy of friction energy generated between the pressure plate and the clutch disk during a period from a fully disengaged state to a fully engaged state of the clutch;
A deformation amount calculation unit that calculates a deformation amount in the thickness direction of the pressure plate from the accumulated energy calculated by the cumulative energy calculation unit;
A correction unit that uses the deformation amount calculated by the deformation amount calculation unit as a stroke correction amount, and corrects the stroke instruction value for the clutch drive mechanism by the stroke correction amount;
A clutch drive control device.

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