JP2011202749A - Power transmission control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquire a touch point of a clutch without affecting the acceleration/deceleration state of a vehicle during traveling of the vehicle in a power transmission control device for the vehicle using a double clutch transmission.SOLUTION: During vehicle traveling, an unselected system (system where the clutch is disengaged) within the transmission is made in an open state (t1). Then, a clutch stroke St2 of the clutch in the unselected system is gradually increased from zero (after t2). Thus, rotational frequency Ni2 of an input shaft in the unselected system is increased. After a time point (t3) where the increased Ni2 reaches engine speed Ne, the St2 is gradually decreased. This decreases the Ni2. The St2 at a time point (t4) where a change rate of the Ni2 becomes zero is acquired as the touch point of the clutch in the unselected system.

Description

  The present invention relates to a vehicle power transmission control device.

  Conventionally, as described in Patent Literature 1 and the like, first and second input shafts to which power is input from a vehicle engine, an output shaft that outputs power to drive wheels of the vehicle, An established state in which any one of a part (for example, a plurality of odd-numbered stages including the first speed) is selectively established to form a power transmission system between the first input shaft and the output shaft, or any shift stage 1st mechanism part which selectively achieves the open state which does not form a power transmission system between the 1st input shaft and the output shaft without establishing, and the remainder (for example, including 2nd gear) Any one of a plurality of even-numbered stages) is selectively established to form a power transmission system between the second input shaft and the output shaft, or the second input shaft without establishing any shift stage. And a second mechanism that selectively achieves an open state in which a power transmission system is not formed between the output shaft and the output shaft. To have.

  This transmission is interposed between the engine output shaft and the first input shaft, and can transmit the maximum torque (clutch torque) between the engine output shaft and the first input shaft by adjusting the clutch stroke. ) That can be transmitted between the engine output shaft and the second input shaft by adjusting the clutch stroke. A second clutch capable of adjusting torque (clutch torque) is combined. A mechanism obtained by such a combination is also called a “double clutch transmission” (hereinafter also referred to as “DCT”).

  Hereinafter, a system configured by the first clutch, the first input shaft, and the first mechanism unit is referred to as a “first system”, and a system configured by the second clutch, the second input shaft, and the second mechanism unit. This is called “second system”. A state where the clutch torque is greater than “0”, that is, a state where the clutch transmits power is referred to as a “engaged state”, and a state where the clutch torque is “0”, ie, the state where the clutch does not transmit power is divided. Called “state”.

  When controlling the DCT, one shift speed to be achieved (hereinafter referred to as “selected shift speed”) is selected based on the operation of the shift lever by the driver of the vehicle and / or the running state of the vehicle. . Hereinafter, among the first and second mechanism units, the first and second clutches, the first and second input shafts, and the first and second systems, the one corresponding to the selected gear stage is referred to as the “selection mechanism unit”. , “Selected clutch”, “Selected input shaft”, “Selected system”, and those that do not correspond to the selected gear stage are “Non-selected mechanism”, “Non-selected clutch”, “Non-selected input shaft”, “ It is called “non-selected line”.

  When the selected gear stage is selected, the selected clutch is controlled to be in an engaged state while the selected gear stage is established in the selection mechanism, and the non-selected clutch is controlled to be in a disconnected state. As a result, a power transmission system having a reduction gear ratio of the selected gear stage is formed between the output shaft of the engine and the output shaft of the transmission via the selected system. The driving torque of the engine (engine torque) is transmitted to the driving wheels via this power transmission system, and the vehicle can be accelerated.

  On the other hand, in the non-selected system, the non-selected clutch is in a disconnected state. Therefore, the non-selection mechanism unit can be kept in a standby state in a state in which the next selected gear stage will be established. If this is utilized, a shift operation (a shift up to change the gear position to the high speed side or a shift down to change to the low speed side) in which the selected system and the non-selected system are switched between the first and second systems is performed. The first and second clutches are simultaneously operated with "operation to change the clutch in the engaged state to the disconnected state" and "operation to change the clutch in the disconnected state to the connected state". Thus, the engine torque can be continuously transmitted to the output shaft of the transmission (accordingly, the drive wheel). As a result, the shift shock can be reduced.

JP 2010-48416 A

  As described above, the clutch torque is adjusted by adjusting the clutch stroke. More specifically, a map that defines the relationship between the clutch stroke and the clutch torque (stroke-torque characteristics) is created (see FIGS. 2 and 6 to be described later). Based on this map and the (target) clutch torque to be achieved, the target clutch stroke is determined. Then, the clutch actuator is controlled so that the actual clutch stroke matches the target clutch stroke. As a result, the actual clutch torque is adjusted to coincide with the target clutch torque.

  By the way, the actual “stroke-torque characteristics” may change due to wear of the friction member of the clutch. Therefore, there may occur a case where the actual characteristic deviates from the characteristic specified in the map. In this case, due to this “deviation”, the target clutch stroke cannot be determined to a value that should be originally determined, and as a result, the actual clutch torque may be adjusted to a value different from the target clutch torque. obtain.

  In order to cope with such a situation, it is necessary to correct the “stroke-torque characteristics” defined in the map so as to coincide with the actual “stroke-torque characteristics”. Hereinafter, the clutch stroke corresponding to the boundary between the engaged state and the disconnected state of the clutch is referred to as “touch point” (or standby point) (see FIG. 2).

  The tendency of the actual characteristic deviation with respect to the characteristic specified in the map appears as a touch point deviation. Therefore, conventionally, every time the engine is started, each time the engine is stopped, the touch point is acquired by actually changing the clutch stroke, and the “stroke-torque characteristic” is defined based on the acquired touch point. It has been widely done to correct.

  However, the actual “stroke-torque characteristics” can change not only due to wear of the friction member of the clutch but also due to expansion caused by heat generation of the friction member when an excessive load is applied to the clutch while the vehicle is running. Therefore, even when the map is corrected when the engine is started, there may still be a situation in which the actual characteristics deviate from the characteristics defined in the map while the vehicle is running.

  Therefore, it is desired to acquire a touch point while the vehicle is traveling. However, in order to acquire the touch point, it is necessary to actually change the clutch stroke so that the clutch is disengaged (clutch torque = 0) for at least a short period of time. For this reason, when a single clutch is provided between the transmission and the engine, it is very difficult to acquire a touch point without affecting the acceleration / deceleration state of the vehicle while the vehicle is running.

  In view of the above, an object of the present invention is to provide a vehicle power transmission control device using DCT that can acquire a touch point of a clutch without affecting the acceleration / deceleration state of the vehicle while the vehicle is running. It is to provide.

  A vehicle power transmission control device according to the present invention includes a first input shaft (Ai1) to which power is input from a drive source (E / G) of a vehicle and a second input shaft (Ai1) to which power is input from the drive source ( Ai2), an output shaft (AO) that outputs power to the driving wheels of the vehicle, and any one of “one or more gears of the first group” that is a part of all of the gears. One of the first input shaft and the first input shaft without establishing either the established state in which a power transmission system is formed between the first input shaft and the output shaft or the first group of gears. A first mechanism unit (M1) that selectively achieves an open state that does not form a power transmission system with the output shaft; and the remaining one of the total gears, “one or more of the second group A power transmission system between the second input shaft and the output shaft by selectively establishing any one of the "speed stages" Or a second mechanism that selectively achieves an open state in which a power transmission system is not formed between the second input shaft and the output shaft without establishing any of the second group shift stages. A transmission (T / M) including a portion (M2). Here, the plurality of shift stages of the first group are provided with a plurality of odd stages including the first speed, and the plurality of shift stages of the second group are provided with a plurality of even stages including the second speed. Is preferred.

  Further, the power transmission control device is interposed between the output shaft of the drive source and the first input shaft, and by adjusting the clutch stroke, the output shaft of the drive source and the first input shaft Between the first clutch (C1) capable of adjusting the clutch torque, which is the maximum torque that can be transmitted between, and the output shaft of the drive source and the second input shaft, and by adjusting the clutch stroke, A second clutch (C2) capable of adjusting a clutch torque that is a maximum torque that can be transmitted between the output shaft of the drive source and the second input shaft; That is, this power transmission control device is a power transmission control device using DCT.

  The power transmission control device includes storage means (ECU) that stores a map that defines the relationship between the clutch stroke and the clutch torque for the first and second clutches. The power transmission control device selects one gear as a selected gear based on the operation of the shift operation member of the vehicle and / or the running state of the vehicle, and the first and second mechanism units Among the first and second clutches, the clutch stroke of the selection clutch corresponding to the selection mechanism is controlled in a state where the selection gear is established. Control based on the map to control the clutch torque of the selected clutch to a target value greater than zero, control the clutch stroke of a non-selected clutch different from the selected clutch, and control the clutch torque of the non-selected clutch to zero The control means (ECU) which performs is provided. That is, the selected clutch is controlled to the engaged state, and the non-selected clutch is controlled to the disconnected state.

  The power transmission control device is characterized in that the control means adjusts the clutch stroke of the non-selection clutch while the non-selection mechanism unit different from the selection mechanism unit is maintained in the released state while the vehicle is running. Then, for the non-selection clutch, a joint in which a power transmission system is formed between the non-selection input shaft corresponding to the non-selection clutch among the first and second input shafts and the output shaft of the drive source. There is an acquisition means for acquiring, as a touch point, a clutch stroke corresponding to a boundary between the state and the divided state where the power transmission system is not formed.

  In the case of DCT, even if the clutch stroke of the non-selection clutch is actually changed while the vehicle is running in a state where the non-selection mechanism is maintained in the open state, the acceleration / deceleration state of the vehicle is not affected ( Few). The above configuration is based on this viewpoint. According to the above configuration, the touch point of the non-selected clutch can be acquired without affecting the acceleration / deceleration state of the vehicle while the vehicle is running by effectively utilizing the above-described viewpoint specific to DCT.

  Accordingly, when the first clutch is a non-selection clutch and when the second clutch is a non-selection clutch while the vehicle is running, the touch points of the non-selection clutch are acquired, respectively. For each clutch, the map defining the “stroke-torque characteristics” can be corrected.

  Specifically, the acquisition means is based on a change in rotational speed of the non-selected input shaft that changes by adjusting a clutch stroke of the non-selected clutch in a state where the non-selective mechanism is maintained in the released state. Configured to obtain the touch point. More specifically, the acquisition means gradually increases the clutch stroke of the non-selection clutch from zero toward the pressure-bonding direction in a state where the non-selection mechanism is maintained in the released state, After the rotational speed of the input shaft matches the rotational speed of the output shaft of the drive source, the clutch stroke of the non-selected clutch is gradually decreased in the separating direction, and the rate of change of the rotational speed of the non-selected input shaft is predetermined. A clutch stroke of the non-selected clutch when the value becomes equal to or less than the value is acquired as the touch point.

It is the schematic diagram which showed the power transmission control apparatus which concerns on embodiment of this invention. 3 is a graph showing a map defining “stroke-torque characteristics” for the clutch shown in FIG. 1. 2 is a graph showing a shift map in which a relationship between “a combination of a vehicle speed and an accelerator opening” and “a shift stage to be achieved” is determined in advance, which is referred to by the ECU shown in FIG. 1. 3 is a flowchart showing a flow of touch point acquisition processing executed by the ECU shown in FIG. 1. It is the time chart which showed an example in case a touch point acquisition process is made during driving | running | working vehicle by the power transmission control apparatus which concerns on embodiment of this invention. It is a figure for demonstrating correction | amendment of the map which prescribes | regulates "stroke-torque characteristic" performed based on the acquired touch point.

  Hereinafter, a vehicle power transmission control device (this device) according to an embodiment of the present invention will be described with reference to the drawings. This device includes a transmission T / M, a first clutch C1, a second clutch C2, and an ECU. The transmission T / M includes six shift speeds (1st to 6th speed) for forward travel of the vehicle and one shift speed (reverse) for reverse travel of the vehicle.

  The transmission T / M includes a first input shaft Ai1, a second input shaft Ai2, an output shaft AO, a first mechanism unit M1, and a second mechanism unit M2. The first and second input shafts Ai1 and Ai2 are supported by a case (not shown) so as to be coaxial and relatively rotatable. The output shaft AO is supported by the case in parallel with the first and second input shafts Ai1 and Ai2 at positions shifted from the first and second input shafts Ai1 and Ai2.

  The first input shaft Ai1 is connected to the output shaft AE of the engine E / G that is a drive source of the vehicle via the first clutch C1. Similarly, the second input shaft Ai1 is connected to the output shaft AE of the engine E / G via the second clutch C2. The output shaft AO is connected to drive wheels of the vehicle so that power can be transmitted.

  The first mechanism M1 is always meshed with a first-speed drive gear G1i and a first-speed driven gear G1o that are always meshed with each other, and a third-speed drive gear G3i and a third-speed driven gear G3o that are always meshed with each other. High-speed drive gear G5i and 5-speed driven gear G5o, reverse drive gear GRi and reverse driven gear GRo that do not always mesh with each other, reverse idle gear GRd that always meshes with drive gear GRi and driven gear GRo, respectively, and sleeve S1 and S2. The sleeves S1 and S2 are driven by sleeve actuators AS1 and AS2, respectively.

  Of the drive gears G1i, G3i, G5i, GRi, G1i, GRi are fixed so as to rotate integrally with the first input shaft Ai1, and G3i, G5i are supported by the first input shaft Ai1 so as to be relatively rotatable. Of the driven gears G1o, G3o, G5o, GRo, G1o, GRo are supported by the output shaft AO so as to be relatively rotatable, and G3o, G5o are fixed so as to rotate integrally with the output shaft AO.

  The sleeve S1 is always spline-fitted to the hub that rotates integrally with the output shaft AO so as to be movable in the axial direction. When the sleeve S1 is in the position shown in FIG. 1 (disconnected position), the sleeve S1 is spline-fitted to both the first speed piece that rotates integrally with the driven gear G1o and the reverse piece that rotates integrally with the driven gear GRo. do not do. When the sleeve S1 moves to the left position (first speed position) from the non-connection position, the sleeve S1 is spline-fitted to the first speed piece, and when the sleeve S1 moves to the right position (reverse position), the sleeve S1 becomes the reverse piece. The spline is mated to it.

  The sleeve S2 is always spline-fitted so as to be movable in the axial direction with respect to the hub that rotates integrally with the first input shaft Ai1. When the sleeve S2 is in the position shown in FIG. 1 (disconnected position), the sleeve S2 is spline-fitted to both the third speed piece that rotates integrally with the drive gear G3i and the fifth speed piece that rotates integrally with the drive gear G5i. Do not match. When the sleeve S2 moves to the left position (third speed position) from the non-connection position, the sleeve S2 is spline-fitted to the third speed piece, and when the sleeve S2 moves to the right position (fifth speed position), the sleeve S2 moves to the fifth speed. Spline fit to the piece.

  As described above, in the first mechanism unit M1, when the sleeves S1 and S2 are both adjusted to the non-connection position, a neutral state in which no power transmission system is formed between the first input shaft Ai1 and the output shaft AO is obtained. When the sleeve S1 moves to the 1st speed position in the neutral state, a power transmission system having a 1st speed reduction ratio is formed (1st speed is established), and when the sleeve S1 moves to the reverse position in the neutral state, the reverse reduction ratio Is formed (reverse is established). When the sleeve S2 moves to the 3rd speed position in the neutral state, a power transmission system having a reduction ratio of 3rd speed is formed (3rd speed is established), and when the sleeve S2 moves to the 5th speed position in the neutral state, A power transmission system having a reduction ratio is formed (5th speed is established).

  The second mechanism portion M2 is always meshed with a second-speed drive gear G2i and a second-speed driven gear G2o that are always meshed with each other, and a fourth-speed drive gear G4i and a fourth-speed driven gear G4o that are always meshed with each other. A high-speed driving gear G6i, a sixth-speed driven gear G6o, and sleeves S3 and S4 are provided. The sleeves S3 and S4 are driven by sleeve actuators AS3 and AS4, respectively.

  The drive gears G2i, G4i, and G6i are all fixed to the second input shaft Ai2 so as to rotate integrally. The driven gears G2o, G4o, G6o are all supported by the output shaft AO so as to be relatively rotatable.

  The sleeve S3 is always spline-fitted to the hub that rotates integrally with the output shaft AO so as to be movable in the axial direction. When the sleeve S3 is in the position shown in FIG. 1 (non-connection position), the sleeve S3 is splined to both the second speed piece that rotates integrally with the driven gear G2o and the fourth speed piece that rotates integrally with the driven gear G4o. Do not match. When the sleeve S3 is moved to the right position (second speed position) from the non-connection position, the sleeve S3 is spline-fitted to the second speed piece, and when the sleeve S3 is moved to the left position (fourth speed position), the sleeve S3 is fourth speed. Spline fit to the piece.

  The sleeve S4 is always spline-fitted to the hub rotating integrally with the output shaft AO so as to be movable in the axial direction. When the sleeve S4 is in the position shown in FIG. 1 (disconnected position), the sleeve S4 is not spline-fitted to the sixth speed piece that rotates integrally with the driven gear G6o. When the sleeve S4 moves to the right side position (sixth speed position) from the non-connection position, the sleeve S4 is spline-fitted to the sixth speed piece.

  As described above, in the second mechanism unit M2, when the sleeves S3 and S4 are both adjusted to the non-connection position, a neutral state in which no power transmission system is formed between the second input shaft Ai2 and the output shaft AO is obtained. When the sleeve S3 moves to the 2nd speed position in the neutral state, a power transmission system having a reduction ratio of 2nd speed is formed (2nd speed is established). When the sleeve S3 moves to the 4th speed position in the neutral state, the 4th speed A power transmission system having a reduction ratio is formed (fourth speed is established). When the sleeve S4 moves to the 6th speed position in the neutral state, a power transmission system having a 6th speed reduction ratio is formed (6th speed is established).

  The first and second clutches C1 and C2 are coaxially arranged in series in the axial direction. The clutch stroke St1 of the first clutch C1 is adjusted by the clutch actuator AC1. As shown in FIG. 2, the maximum torque (first clutch torque Tc1) that can be transmitted by the first clutch C1 can be adjusted by adjusting the clutch stroke St1. In the state of “Tc1 = 0”, a power transmission system is not formed between the output shaft AE of the engine E / G and the first input shaft Ai1. This state is referred to as “divided state”. In the state of “Tc1> 0”, a power transmission system is formed between the output shaft AE of the engine E / G and the first input shaft Ai1. This state is called a “joined state”. The clutch stroke means the amount of movement of the friction member driven by the clutch actuator from the original position (clutch stroke = 0) in the pressure-bonding direction (increase direction of the clutch torque).

  Similarly, the clutch stroke St2 of the second clutch C2 is adjusted by the clutch actuator AC2. As shown in FIG. 2, the maximum torque (second clutch torque Tc2) that can be transmitted by the second clutch C2 can be adjusted by adjusting the clutch stroke St2. Similarly to the first clutch C1, the “separated state” and the “engaged state” are defined for the second clutch C2.

  In addition, this apparatus detects a wheel speed sensor V1 that detects a wheel speed of a vehicle wheel, an accelerator opening sensor V2 that detects an operation amount (accelerator opening) of an accelerator pedal AP, and a position of a shift lever SF. Shift position sensor V3.

  Furthermore, this apparatus includes an electronic control unit ECU. The ECU controls the clutch actuators AC1 and AC2 and the sleeve actuators AS1 to AS4 based on the information from the sensors V1 to V3, and the first and second gears of the transmission T / M. The state of the clutches C1 and C2 is controlled. As described above, this device is a power transmission device using a double clutch transmission (DCT).

(Normal control)
In this apparatus, when the position of the shift lever SF is at a position corresponding to the “automatic mode”, the transmission T / M is controlled based on the shift map shown in FIG. 3 stored in the ROM (not shown) in the ECU. A gear position is determined. More specifically, in the present device, the combination of the vehicle speed calculated based on the wheel speed obtained from the wheel speed sensor V1 and the accelerator opening obtained from the accelerator opening sensor V2 indicates which speed change on the shift map. One gear to be achieved (hereinafter referred to as “selected gear”) is selected depending on whether the gear corresponds to the region of the gear. For example, when the current vehicle speed is α and the current accelerator opening is β (see the black dots shown in FIG. 3), “3rd speed” is selected as the selected shift speed.

  The shift map shown in FIG. 3 can be obtained by repeatedly performing an experiment that matches the optimum shift speed with respect to the combination of the vehicle speed and the accelerator opening while changing the combination in various ways. The shift map is stored in a ROM in the ECU. When the shift lever SF is in a position corresponding to the “manual mode”, the selected shift speed is selected based on the operation of the shift lever SF by the driver.

  Hereinafter, for convenience of explanation, a system including the first clutch C1, the first input shaft Ai1, and the first mechanism unit M1 is referred to as a “first system”, and the second clutch C2, the second input shaft Ai2, The system composed of the two mechanism units M2 is referred to as a “second system”. Further, the first and second mechanism portions M1 and M2, the first and second clutches C1 and C2, the first and second input shafts Ai1 and Ai2, and the first and second systems correspond to the selected shift speed. These are called “selection mechanism”, “selection clutch”, “selection input shaft”, and “selection system”, respectively, and the ones that do not correspond to the selected shift stage are “nonselection mechanism” and “nonselection clutch”, respectively. These are called “non-selected input shaft” and “non-selected system”.

  As described above, in the transmission T / M, an odd-numbered stage including the first speed (first speed, third speed, and fifth speed) can be selectively established in the first mechanism unit M1, and the second mechanism unit M2 Even-numbered stages including 2nd speed (2nd speed, 4th speed, 6th speed) can be selectively established. Therefore, every time the selected shift stage is changed (shifted up) from the current shift stage to a shift stage that is one speed higher than the current shift stage, or the selected shift stage changes from the current shift stage to the current shift stage. Each time the gear is changed (shifted down) to the lower speed side by one stage, the selected system and the non-selected system are switched between the first and second systems.

  When the selected shift speed is selected based on the shift map, the selected clutch is controlled to be in a connected state while the selected shift speed is established in the selection mechanism, and the non-selected clutch is controlled to be disconnected. The clutch torque of the selected clutch in the engaged state can be set to an arbitrary value within a range larger than the drive torque (engine torque) of the engine E / G (that is, within a range in which the selected clutch does not slip). For example, the clutch torque of the selected clutch in the engaged state may be set to the maximum value Tmax (see FIG. 2), or may be adjusted to a value that is larger than the engine torque by a certain value.

  Thereby, a power transmission system having a reduction gear ratio of the selected gear stage is formed between the output shaft AE of the engine E / G and the output shaft AO of the transmission T / M via the selected system. Therefore, engine torque can be transmitted to the drive wheels via the selected system.

  On the other hand, in the non-selected system, the non-selected clutch is in a disconnected state (clutch torque = 0). Accordingly, the non-selection mechanism unit is made to stand by in a state where the gear stage to be the next selected gear stage (specifically, the gear stage on the high speed side or the low speed side by one stage from the currently selected gear stage) is established. I can leave. Specifically, for example, when the currently selected shift speed is “3rd speed” (that is, when the first mechanism M1 becomes the selection mechanism), the second mechanism M2 that is a non-selection mechanism is set to “4”. It is possible to wait in a state where “speed” or “second speed” is established.

  In this device, one of the well-known methods is used to shift up and down based on the transition of the driving state of the vehicle up to now (for example, transition of vehicle speed, transition of engine torque, transition of accelerator opening, etc.). Which is to be done next is predicted. Then, when it is predicted that a shift up will be made, the non-selection mechanism unit is put on standby in a “state in which a shift stage on the high speed side is established by one stage from the currently selected shift stage”. When it is predicted that a downshift will be made, the non-selection mechanism unit is made to wait in a “state in which a shift stage on the lower speed side by one stage than the currently selected shift stage has been established”.

  In addition, in the present device, the first and second clutches are selected when the selected shift speed is changed by a change in the vehicle state (combination of vehicle speed and accelerator opening), that is, when upshifting or downshifting is performed. The operation of switching the selected clutch and the non-selected clutch between them (that is, “the operation of changing the clutch in the engaged state to the disconnected state” and “the operation of changing the clutch in the disconnected state to the connected state”) at the same time Executed. As a result, when shifting up or down, the engine torque can be transmitted to the output shaft AE (and hence the drive wheels) of the transmission T / M without interruption. As a result, the shift shock can be reduced. The normal control by this apparatus has been described above.

(Acquisition of touch points)
As described above, for the first and second clutches C1 and C2, the clutch torque is adjusted by adjusting the clutch stroke. More specifically, the target clutch stroke is determined based on a map that preliminarily creates the “stroke-torque characteristics” shown in FIG. 2 and the (target) clutch torque to be achieved. The clutch actuator is controlled so that the actual clutch stroke matches this target clutch stroke. As a result, the actual clutch torque is adjusted to coincide with the target clutch torque.

  By the way, the actual “stroke-torque characteristics” can change due to wear of the friction member of the clutch, expansion due to heat generation of the friction member due to an excessive load acting on the clutch during traveling of the vehicle, and the like. Therefore, there may occur a case where the actual characteristic deviates from the characteristic specified in the map. When such “deviation” occurs, the target clutch stroke cannot be determined to a value that should be originally determined. As a result, a situation may occur in which the actual clutch torque is adjusted to a value different from the target clutch torque.

  In order to cope with such a situation, it is necessary to correct the “stroke-torque characteristics” defined in the map so as to coincide with the actual “stroke-torque characteristics”. Here, the clutch stroke corresponding to the boundary between the engaged state and the disconnected state of the clutch is called a “touch point” (or a standby point) (see FIG. 2). The tendency of the actual characteristic deviation with respect to the characteristic specified in the map appears as a touch point deviation. From the above, in this device, a touch point is acquired while the vehicle is traveling.

  In order to acquire the touch point, it is necessary to actually change the clutch stroke so that the clutch is disengaged (clutch torque = 0) for at least a short period of time. Therefore, when a single clutch is provided between the transmission and the engine, it is very difficult to acquire a touch point without affecting the acceleration / deceleration state of the vehicle while the vehicle is running.

  On the other hand, in the case of DCT, in the state where the non-selection mechanism portion is maintained in the open state, even if the clutch stroke of the non-selection clutch is actually changed while the vehicle is running, the acceleration / deceleration state of the vehicle is affected. There is nothing (less). In this apparatus, this viewpoint peculiar to DCT is utilized effectively, and the touch point of a non-selection clutch is acquired.

  Hereinafter, the control of this apparatus in the case where the process of acquiring a touch point (touch point acquisition process) is performed while the vehicle is running will be described with reference to the flowchart shown in FIG. 4 and the time chart shown in FIG. . In FIG. 5, NE is the rotational speed (engine rotational speed) of the output shaft AE of the engine E / G, Ni1 and Ni2 are the rotational speeds of the first and second input shafts Ai1 and Ai2, respectively, and St1, St2 Are clutch strokes of the first and second clutches, respectively. Note that NE, Ni1, Ni2, St1, and St2 can be detected based on information from a sensor (not shown).

  In the present apparatus (ECU), first, in step 405, it is determined whether or not the acquisition condition is satisfied. If it is determined as “No”, this process ends. This acquisition condition is satisfied, for example, when the vehicle is traveling (vehicle speed> 0) and the vehicle has traveled more than a predetermined distance since the last acquisition of the touch point.

  When the acquisition condition is satisfied (“Yes” in step 405), in step 410, the non-selection mechanism unit is maintained in an open state. Specifically, when the non-selection mechanism unit is in the open state before the acquisition condition is satisfied, the non-selection mechanism unit is continuously maintained in the open state. On the other hand, if any shift stage is established in the non-selection mechanism unit before the acquisition condition is satisfied, the non-selection mechanism unit is changed / maintained to the open state based on the satisfaction of the acquisition condition.

  In the example shown in FIG. 5, before the time t1 when the acquisition condition is satisfied, the first and second systems are set to the selected system and the non-selected system, respectively, and “first speed” is selected in the first mechanism unit M1 that is the selection mechanism unit. Is established, and “fourth speed” is established in the second mechanism portion M2 which is a non-selection mechanism portion. The clutch stroke St1 of the first clutch C1, which is the selected clutch, is adjusted to a sufficiently large predetermined value so that the first clutch torque Tc1 is larger than the engine torque. Therefore, no slip has occurred in the first clutch C1, and therefore the rotational speed Ni1 of the first input shaft Ai1 that is the selected input shaft is the engine rotational speed NE (that is, the reduction ratio of “third speed” and the current The rotational speed determined by the vehicle speed). Further, the rotational speed Ni2 of the second input shaft Ai2, which is a non-selected input shaft, is a rotational speed determined by the reduction ratio of “fourth speed” and the current vehicle speed (Ni2 <Ni1). On the other hand, the clutch stroke St2 of the second clutch C2, which is a non-selected clutch, is maintained at “0” in order to set the second clutch torque Tc2 to “0”.

  At time t1, the above-described acquisition condition is satisfied (“Yes” in step 405), and step 410 is executed, so that the second mechanism unit M2, which is a non-selected mechanism unit, establishes “fourth speed”. The changed state is changed to the open state. As a result, the second input shaft Ai2 is in a state where it does not receive power transmission from either the engine side or the drive wheel side. As a result, after time t1, the rotational speed Ni2 of the second input shaft Ai2 decreases from the rotational speed determined by the reduction ratio of “fourth speed” and the current vehicle speed. Thereafter, the rotational speed Ni2 is affected by the inertia torque of the second input shaft Ai2 and the viscous torque caused by the lubricating oil in the transmission T / M, and changes at a certain small value.

  In step 415, the clutch stroke of the non-selected clutch is gradually increased from “0”. This process is started when a predetermined time elapses from the establishment of the acquisition condition described above. In the example shown in FIG. 5, the clutch stroke St2 of the second clutch C2, which is a non-selected clutch, is gradually increased from “0” from time t2 when the predetermined time has elapsed from time t1.

  By executing this process, the second input shaft Ai2, which is a non-selected input shaft, receives power from the engine side. The power received by the second input shaft Ai2 gradually increases as the second clutch torque Tc2 increases due to the increase in the clutch stroke St2. As a result, after time t2 (more precisely, after the time when the clutch stroke St2 exceeds the actual touch point of the second clutch C2), the rotational speed Ni2 of the second input shaft Ai2 is from the “small value” described above. It gradually increases.

  In step 420, it is determined whether or not the rotational speed of the non-selected input shaft matches the engine rotational speed NE. If it is determined “No”, the processing in step 415 is repeated. That is, the clutch stroke of the non-selected clutch continues to increase until the rotational speed of the non-selected input shaft matches the engine rotational speed NE. In the example shown in FIG. 5, the increase in the clutch stroke St2 of the second clutch C2 is continued until the time t3 when the rotational speed Ni2 of the second input shaft Ai2 matches the engine rotational speed NE.

  When the rotational speed of the non-selected input shaft matches the engine rotational speed NE, in step 425, the clutch stroke of the non-selected clutch is gradually reduced. In the example shown in FIG. 5, the clutch stroke St2 is gradually reduced from time t3. As a result, the power received by the second input shaft Ai2 from the engine side gradually decreases due to the decrease in the second clutch torque Tc2 due to the decrease in the clutch stroke St2. As a result, the rotational speed Ni2 of the second input shaft Ai2 gradually decreases after time t3.

  In step 430, it is determined whether or not the rate of change of the rotational speed of the non-selected input shaft matches “0”. If it is determined “No”, the processing in step 425 is repeated. That is, the reduction of the clutch stroke of the non-selected clutch is continued until the rate of change of the rotational speed of the non-selected input shaft becomes “0”. In the example shown in FIG. 5, the decrease in the clutch stroke St2 of the second clutch C2 is continued until time t4 when the decrease in the rotation speed Ni2 of the second input shaft Ai2 ends and the rate of change of the rotation speed Ni2 becomes “0”. Will continue.

  When the rate of change in the rotational speed of the non-selected input shaft matches “0”, in step 435, the current clutch stroke of the non-selected clutch is acquired as the touch point of the non-selected clutch. In the example shown in FIG. 5, the clutch stroke St2 at time t4 is acquired as the touch point Strearn of the second clutch C2. This process is as follows: “After the time when the clutch stroke passes the touch point, the power received by the non-selected input shaft from the engine side becomes zero, and the rotational speed of the non-selected input shaft changes constantly at the“ small value ”described above. It will be based on what is considered.

  The touch point Strarn acquired in this way is used for correction of a map that defines the “stroke-torque characteristic” of the non-selected clutch. For example, in the example illustrated in FIG. 5, the touch point Strearn of the second clutch C2 is acquired. As shown in FIG. 6, when the touch point in the map that defines the “stroke-torque characteristic” of the second clutch C2 currently stored in the ROM in the ECU is Stmem (<Strearn), the characteristic of this map is The characteristic indicated by the solid line is corrected to the characteristic indicated by the broken line. After this correction, the target clutch stroke of the second clutch C2 is determined to be a value that should originally be determined. As a result, the actual clutch torque of the second clutch C2 matches the target clutch torque.

  In the present device, the touch point acquisition process similar to that described above is also executed when the first clutch C1 is a non-selected clutch. As a result, the map (see FIG. 2) defining the “stroke-torque characteristics” is corrected for each of the first and second clutches C1 and C2.

(Action / Effect)
As described above, according to this device, “in the state where the non-selection mechanism portion is maintained in the open state, even if the clutch stroke of the non-selection clutch is actually changed while the vehicle is running, the acceleration / deceleration state of the vehicle is affected. By effectively utilizing the DCT-specific feature of “nothing”, the touch point of the clutch can be acquired without affecting the acceleration / deceleration state of the vehicle while the vehicle is running.

  The present invention is not limited to the above embodiment, and various modifications can be employed within the scope of the present invention. For example, in the above embodiment, the clutch stroke of the non-selected clutch when the rate of change in the rotational speed of the non-selected input shaft matches “0” is acquired as the touch point of the non-selected clutch. The clutch stroke of the non-selected clutch when the change rate (the absolute value thereof) of the rotational speed of the shaft is less than or equal to a small value greater than “0” may be acquired as the touch point of the non-selected clutch.

  In addition, in the above embodiment, the touch of the non-selected clutch is based on the fact that the change rate of the rotational speed of the non-selected input shaft has changed from non-zero to zero in the process of gradually decreasing the clutch stroke of the non-selected clutch. Although the point has been acquired (see time t4 in FIG. 5), the rate of change in the rotational speed of the non-selected input shaft changes from zero to non-zero in the process where the clutch stroke of the non-selected clutch gradually increases from zero. The touch point of the non-selected clutch may be acquired based on the change (see time t5 in FIG. 5).

  In the actual “stroke-torque characteristics” of the clutch, due to the influence of hysteresis, there may be a difference between the characteristics in the process of increasing the clutch stroke and the characteristics in the process of decreasing the clutch stroke. Therefore, the touch point when the clutch stroke increases (clutch stroke where the clutch torque changes from zero to non-zero) and the touch point when the clutch stroke decreases (clutch torque changes from non-zero to zero). Deviations can also occur between changing clutch strokes). Therefore, when this hysteresis is considered, it is necessary to distinguish these two touch points.

  T / M ... manual transmission, E / G ... engine, C1, C2 ... first and second clutches, Ai1, Ai2 ... first, second input shaft, AO ... output shaft, M1, M2 ... first, first 2 mechanical parts, AC1, AC2 ... clutch actuator, AS1 to AS4 ... sleeve actuator, V1 ... wheel speed sensor, V2 ... accelerator opening sensor, ECU ... electronic control unit

Claims (2)

A first input shaft to which power is input from a drive source of the vehicle; a second input shaft to which power is input from the drive source; an output shaft that outputs power to the drive wheels of the vehicle; and a plurality of all speed stages And establishes a power transmission system between the first input shaft and the output shaft by selectively establishing any one of one or a plurality of shift speeds of a first group that is a part of the first group. A first mechanism part that selectively achieves an open state in which no power transmission system is formed between the first input shaft and the output shaft without establishing any of the state or the first group of gears; and A power transmission system is formed between the second input shaft and the output shaft by selectively establishing one or a plurality of gears of the second group, which is the remaining of all gears. The second input shaft and the output shaft without establishing either the established state or the second group of gears A transmission having a second mechanism for selectively achieving an open state of not forming a power transmission system, the between,
The maximum torque that is interposed between the output shaft of the drive source and the first input shaft and can be transmitted between the output shaft of the drive source and the first input shaft by adjusting the clutch stroke. A first clutch capable of adjusting clutch torque;
The maximum torque that is interposed between the output shaft of the drive source and the second input shaft and can be transmitted between the output shaft of the drive source and the second input shaft by adjusting the clutch stroke. A second clutch capable of adjusting the clutch torque;
Storage means for storing a map defining a relationship between a clutch stroke and a clutch torque for the first and second clutches;
One shift stage is selected as the selected shift stage based on the operation of the shift operation member of the vehicle and / or the running state of the vehicle, and corresponds to the selected shift stage among the first and second mechanism portions. In the state where the selection gear stage is established by controlling the selection mechanism portion to be controlled, the clutch stroke of the selection clutch corresponding to the selection mechanism portion among the first and second clutches is controlled based on the map, and Control means for controlling the clutch torque of the selected clutch to a target value greater than zero, controlling the clutch stroke of the non-selected clutch different from the selected clutch, and controlling the clutch torque of the non-selected clutch to zero;
In a vehicle power transmission control device comprising:
The control means includes
While the vehicle is running, the clutch stroke of the non-selection clutch is adjusted in a state where a non-selection mechanism unit different from the selection mechanism unit is maintained in the released state, and the first and second Boundary between a joined state in which a power transmission system is formed between a non-selected input shaft corresponding to the non-selected clutch among the two input shafts and an output shaft of the drive source and a divided state in which the power transmission system is not formed An acquisition means for acquiring a clutch stroke corresponding to a touch point;
The acquisition means includes
In a state where the non-selection mechanism portion is maintained in the released state, the clutch stroke of the non-selection clutch gradually increases from zero in the pressure-bonding direction, and the rotational speed of the non-selection input shaft is increased by the output of the drive source. The non-selection clutch when the clutch stroke of the non-selection clutch is gradually decreased in the separation direction after the rotation speed of the non-selection clutch is equal to the rotational speed of the shaft, and the rate of change of the rotation speed of the non-selection input shaft becomes a predetermined value or less. A vehicle power transmission control device configured to acquire the clutch stroke of the vehicle as the touch point. The power transmission control device for a vehicle according to claim 1,
The transmission is
A power transmission control device for a vehicle, comprising: a plurality of odd speed stages including a first speed as the plurality of shift stages of the first group; and a plurality of even speed stages including a second speed as the plurality of shift stages of the second group.

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