JP4200698B2 - Starting clutch control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a starting clutch of a vehicle such as an automobile, and more particularly to a starting clutch control device.
[0002]
[Prior art]
As one of starting clutch control devices for controlling a starting clutch provided in a power transmission path between a driving source such as an engine and driving wheels, a garage is disclosed in, for example, JP-A-63-207733. There is already a start clutch control device configured to control the engagement clutch engagement pressure in an increasing direction when a shift is performed, that is, when the shift position of the shift lever is switched from the non-travel range to the travel range. Are known.
[0003]
According to such a start clutch control device, the start clutch can be surely brought into the loose engagement state in a short time, and even if the throttle opening is greatly increased immediately after switching to the travel range, the engine blows. The vehicle can be started quickly without rising.
[0004]
[Problems to be solved by the invention]
However, when the garage shift is performed, it is not necessary to control the starting clutch engagement pressure in an increasing direction, and it is necessary to increase the starting clutch engagement pressure according to the situation of the vehicle. The invention described in the above publication has room for improvement in this respect.
[0005]
  For example, if the engagement pressure of the start clutch is increased without considering the control mode in which the start clutch is controlled in accordance with the vehicle conditions during a garage shift, the start clutch is disengaged from the fully engaged state. There is a possibility that a delay may occur in the control because an operation such as returning to the position is required. If the shift lever is operated from the non-traveling position to the traveling position while the vehicle is traveling at a high vehicle speed range, the starting clutch is engaged from the disengaged state.Cut offThere is a risk that a shock may occur due to the change.
[0006]
  The present invention has been made in view of the above-mentioned problems in the conventional starting clutch control device, and the main problem of the present invention is as follows.A starting clutch control device that controls a starting clutch provided in a power transmission path for transmitting power from an engine to a driving wheel without going through a fluid torque converter, based on a shift position of a shift lever,When the shift position of the shift lever is switched from the non-traveling range to the traveling rangeTogetherThe shift position of the shift lever is changed to the non-running range by changing the control mode of the engagement clutch engagement pressure according to the vehicle condition.ThanTraveling rangeWhatSmooth transition of start clutch control without causing problems such as control delays and shocks when switched.Provided is a starting clutch control deviceThat is.
[0007]
[Means for Solving the Problems]
  The main problems mentioned above are according to the present invention.A start clutch provided in the power transmission path that transmits power from the engine to the drive wheels without going through the fluid torque converter.Based on the shift position of the shift leverSystemUntil the control of the engagement clutch engagement pressure associated with the shift operation from the non-travel position to the travel position is completed,By controlling the engagement pressure of the starting clutch in the first fill and constant pressure standbyThe start clutch is maintained in a non-engaged state immediately before torque transmission becomes possible, and after the control of the engagement pressure of the start clutch accompanying the shift operation from the non-travel position to the travel position is completed, the start clutch Is controlled to an engaged state corresponding to the control mode, or a starting clutch control device (configuration of claim 1), orA start clutch provided in the power transmission path that transmits power from the engine to the drive wheels without going through the fluid torque converter.Based on the shift position of the shift leverSystemThe starting clutch control deviceWhen it is determined whether or not the vehicle driving region is in the start clutch control region, and it is determined that the vehicle driving region is in the start clutch control region,Travel positionRunShift to line positionUntil the control of the engagement pressure of the start clutch is completed by controlling the engagement pressure of the start clutch in the first fill and constant pressure standby.The starting clutchNon- just before torque transmission is possibleKeep it engaged,After the control of the engagement pressure of the starting clutch accompanying the shift operation from the non-traveling position to the traveling position is completed,The starting clutchDepending on the control modeThis is achieved by a starting clutch control device (structure of claim 2) characterized by controlling to an engaged state.
[0009]
[Action and effect of the invention]
  According to the configuration of the first aspect, the start clutch control device is in a state where the control of the engagement pressure of the start clutch accompanying the shift operation from the non-travel position to the travel position is completed.By controlling the engagement pressure of the starting clutch in the first fill and constant pressure standbyAfter the start clutch is maintained in the non-engaged state immediately before torque transmission is possible and the control of the start clutch engagement pressure accompanying the shift operation from the non-travel position to the travel position is completed, the start clutch is controlled. Since the engagement state is controlled according to the mode, the control of the starting clutch accompanying the shift operation from the non-travel position to the travel position is any control mode control.By controlling the engagement pressure of the starting clutch in the first fill and constant pressure standbyUnengaged state just before torque transmission is possibleAtThe start clutch control can be started, and therefore the start clutch control can be smoothly transferred while reliably preventing a shock from being generated by switching the start clutch from the released state to the engaged state. .
[0010]
  According to the configuration of claim 2 above,When it is determined whether or not the vehicle driving region is in the start clutch control region, and it is determined that the vehicle driving region is in the start clutch control region,Travel positionRunShift to line positionUntil the control of the engagement pressure of the start clutch is completed by controlling the engagement pressure of the start clutch in the first fill and constant pressure standby.The starting clutchNon- just before torque transmission is possibleKeep it engaged,After the control of the engagement pressure of the starting clutch accompanying the shift operation from the non-traveling position to the traveling position is completed,The starting clutchDepending on the control modeSince it is controlled to the engaged state, the vehicleIs determined to be in the starting clutch control regionIn caseAs in the case of the configuration of claim 1, the start clutch control is started in the non-engagement state immediately before torque transmission becomes possible by controlling the engagement pressure of the start clutch in the first fill and constant pressure standby.Can and followDepartIt is possible to reliably prevent the occurrence of shock due to the forward clutch being switched from the non-engaged state to the engaged state,When it is determined that the vehicle operating region is not in the starting clutch control region, the control of the engagement pressure of the starting clutch is performed unnecessarily.This can be prevented.
[0014]
[Preferred embodiment of the problem solving means]
  The present inventionOneAccording to one preferred embodiment, the aboveClaim 1 orIn the configuration of 2, the start clutch control device has a first fill, a constant pressure standby, a sweep-up, and an end control when the start clutch control is not engaged when the vehicle operating range is not in the start clutch control range. Is configured to control the engagement pressure of the start clutch (preferred embodiment)1).
[0015]
  According to another preferred embodiment of the present invention, the preferred embodiment described above.1In this configuration, the start clutch control device sweeps up when coast control is terminated due to an increase in vehicle speed even when the vehicle operating range is not in the start clutch control range and the start clutch control is not engaged. And the control for controlling the engagement pressure of the starting clutch in the final control (preferred embodiment)2).
[0017]
  According to another preferred embodiment of the present invention, the above claim 1OrIn the configuration of 2, in the case where the starting clutch control device controls the starting clutch to the engaged state corresponding to the control mode, the transition to the control mode is a shift to the control for increasing the engagement pressure. Is configured to perform a first fill (preferred embodiment3).
[0018]
  According to another preferred embodiment of the present invention, the preferred embodiment described above.3In this configuration, when the control mode shifts to the control in which the engagement pressure is increased during execution of the first fill, the starting clutch control device performs the first fill based on the start of the previous control mode. Configured to control execution time (preferred embodiment4).
[0020]
  According to another preferred embodiment of the present invention, the above claim 1Or 2In this configuration, the starting clutch is configured to be positioned in a power transmission path between the engine and the transmission (preferred embodiment).5).
[0021]
  According to another preferred embodiment of the present invention, the preferred embodiment described above.5In this configuration, the transmission includes a continuously variable transmission mechanism and a forward / reverse switching device, and the starting clutch is configured to be a forward clutch of the forward / reverse switching device (preferred embodiment).6).
[0022]
  According to another preferred embodiment of the present invention, the preferred embodiment described above.6In this configuration, the transmission includes a continuously variable transmission mechanism and a forward / reverse switching device, and the starting clutch is configured to be positioned in a power transmission path between the engine and the forward / reverse switching device (preferred embodiment).7).
[0023]
  According to another preferred embodiment of the present invention, the above claim 1Or 2In this configuration, the starting clutch is configured to be positioned in a power transmission path between the transmission and the drive wheel (preferred embodiment).8).
[0024]
  According to another preferred embodiment of the present invention, the above claim 1Or 2The starting clutch is configured to be a starting clutch of an automatic transmission (preferred embodiment)9).
[0025]
DETAILED DESCRIPTION OF THE INVENTION
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments (hereinafter simply referred to as embodiments) of the present invention will be described in detail below with reference to the accompanying drawings.
[0026]
First embodiment
FIG. 1 is a skeleton diagram showing a vehicle power transmission device to which an embodiment of a starting clutch control device according to the present invention is applied. For the sake of simplification, only the upper half of the forward / reverse switching device is shown in FIG.
[0027]
In FIG. 1, a power transmission device 10 is configured to be suitable for a horizontal FF (front engine / front drive) vehicle, for example, and includes an engine 12 that is an internal combustion engine as a driving power source. . The output of the engine 12 is transmitted to the differential gear device 22 through the forward / reverse switching device 16, the belt-type continuously variable transmission mechanism (CVT) 18, and the reduction gear device 20, and a pair not shown in FIG. Is transmitted to the left and right drive wheels 24L and 24R through the universal joint.
[0028]
The forward / reverse switching device 16 is a device for switching forward / backward movement of the vehicle, and in the illustrated embodiment, is constituted by a double pinion type planetary gear device. The input shaft 26 of the forward / reverse switching device 16 connected to the crankshaft 12a of the engine 12 is connected to the sun gear 16s, and the input shaft 36 of the belt type continuously variable transmission mechanism structure 18 is connected to the carrier 16c.
[0029]
A hydraulic forward clutch 38 is disposed between the carrier 16c and the sun gear 16s. Although not shown in the drawing, the clutch plate of the forward clutch 38 is driven by the piston of the hydraulic cylinder, and the piston of the hydraulic cylinder. Is biased to the release position of the forward clutch 38 by a return spring. In particular, when the shift lever 28 is set to a forward travel range such as the D, 2 or L range, the hydraulic pressure Pclt of the hydraulic cylinder is increased by the hydraulic control circuit 39, and the piston moves against the spring force of the return spring 38. The forward clutch 38 is engaged, whereby the input shaft 26 is directly connected to the input shaft 36, and the forward / reverse switching device 16 rotates integrally with the input shaft 36, thereby moving forward. Is transmitted to the drive wheels 24R and 24L via the belt type continuously variable transmission mechanism 18 and the like.
[0030]
On the other hand, when the shift lever 28 is set to the R range that is the reverse travel range, the hydraulic reverse brake 40 disposed between the ring gear 16r and a non-rotating member such as a housing is controlled by the hydraulic control circuit 39. Thus, the ring gear 16r is engaged with the non-rotating member, and the forward clutch 38 is released by being controlled by the hydraulic control circuit 39, so that the input shaft 36 rotates in the direction opposite to that of the input shaft 26. As a result, the driving force in the reverse direction is transmitted to the drive wheels 24R and 24L via the belt type continuously variable transmission mechanism structure 18 or the like. In the illustrated embodiment, the forward clutch 38 is used as a starting clutch, as will be described later.
[0031]
The belt type continuously variable transmission mechanism 18 includes an input side variable pulley device 42 having a variable effective diameter provided on the input shaft 36, an output side variable pulley device 46 having a variable effective diameter provided on the output shaft 44, and And the transmission belt 48 wound around the V groove of the variable pulley devices 42 and 46, and the frictional force between the transmission belt 48 functioning as a power transmission member and the wall surface of the V groove of the variable pulley devices 42 and 46. Power is transmitted through the.
[0032]
The input-side variable pulley device 42 has an input-side hydraulic cylinder 42c for changing the V groove width, that is, the winding diameter (effective diameter) of the transmission belt 48, and the hydraulic fluid 42 supplied to and discharged from the hydraulic cylinder 42c. The oil pressure Pa is controlled by the oil pressure control circuit 52, whereby the V groove width of the variable pulley device 42 is changed to change the winding diameter of the transmission belt 48, and the gear ratio γ (= input side rotation speed Nin / output side rotation). The speed Nout) is continuously changed steplessly.
[0033]
Similarly, the output side variable pulley device 46 has an output side hydraulic cylinder 46c for changing the V groove width, and the hydraulic pressure Pb in the hydraulic cylinder 46c is also regulated by the hydraulic control circuit 52, whereby the transmission belt 48 is adjusted. The tension of the transmission belt 48 is adjusted by adjusting the clamping force of the output-side variable pulley device 46 against the transmission belt 48, and the transmission belt 48 is prevented from sliding with respect to the variable pulley devices 42 and 46. The hydraulic control circuits 39 and 52 are controlled by the electronic control unit 54.
[0034]
The electronic control unit 54 indicates a signal indicating the engine rotational speed Ne detected by the rotational speed sensor 60, a signal indicating the throttle opening θ detected by the throttle opening sensor 62, and the vehicle speed V detected by the vehicle speed sensor 64. A signal and an ON / OFF signal from an idle switch (SW) 66 are input via the engine control device 68.
[0035]
The electronic control unit 54 also includes a signal indicating the rotational speed Nin of the input shaft 36 of the belt type continuously variable transmission mechanism 18 detected by the rotational speed sensor 72 and a signal indicating the shift range detected by the shift position (SP) sensor 74. , A signal indicating the torque of the input shaft 36 (the torque of the output shaft of the forward clutch 38) Tout detected by the torque sensor 76, a signal indicating the hydraulic pressure Pclt of the hydraulic cylinder of the forward clutch 38 detected by the pressure sensor 78, a temperature sensor A signal indicating the temperature Toil of the clutch oil of the forward clutch 38 detected by 80, and an ON-OFF signal indicating whether or not a brake pedal (not shown) is depressed from the brake switch (SW) 82 are input. The
[0036]
The electronic control unit 54 controls the engagement state of the forward clutch 38 according to a forward clutch control routine not shown in the drawing, and the forward clutch 38 and the reverse brake 40 according to a forward / reverse switching control routine not shown in the drawing. Control the engagement state. The electronic control unit 54 controls the input-side rotational speed Nin of the belt-type continuously variable transmission mechanism 18 to a target input-side rotational speed Nint determined by the running state of the vehicle according to a shift control routine not shown in the drawing.
[0037]
In particular, in the illustrated embodiment, the electronic control unit 54 releases the forward clutch 38 when the shift range detected by the shift position sensor 74 is in the N range, P range or R range, but the shift range is D. When the vehicle is in the forward travel range such as the range, in principle, the target transmission torque Tcltt of the forward clutch 38 is calculated based on the throttle opening θ, and the coefficient α based on the oil temperature Toil of the forward clutch 38 detected by the temperature sensor 80. And the target transmission torque generation hydraulic pressure Pcltt necessary to achieve the target transmission torque Tcltt is calculated according to the following equation 1. In Equation 1 below, the coefficient A is the cross-sectional area of the hydraulic cylinder of the forward clutch 38, and W is the load of the return spring.
Pcltt = (α · Tcltt + W) / A (1)
[0038]
The electronic control unit 54 calculates an integral value ΔTi and a differential value ΔTd based on a deviation ΔTp (= Tout−Tcltt) between the output torque Tout detected by the torque sensor 76 and the target transmission torque Tcltt, and Kp, Ki, The PID feedback control amount Ppid is calculated according to the following equation 2 where Kd is a proportional term coefficient, an integral term coefficient, and a derivative term coefficient, respectively.
Ppid = Kp · ΔTp + Ki · ΔTi + Kd · ΔTd (2)
[0039]
The electronic control unit 54 calculates an offset ΔPclt (= Pclta−Pclt) between the instruction oil pressure Pclta for the oil pressure control circuit 39 and the actual oil pressure Pclt detected by the pressure sensor 78, and generates a target transmission torque according to the following equation 3. The command oil pressure Pclta is calculated as the sum of the oil pressure Pcltt, the PID feedback control amount Ppid, and the offset ΔPclt, and the oil pressure (engagement pressure) of the hydraulic cylinder of the forward clutch 38 is controlled based on the command oil pressure Pclta.
Pclta = Pcltt + Ppid + ΔPclt (3)
[0040]
When the garage shift is performed in accordance with the flowchart shown in FIG. 2, that is, when the shift lever 28 is switched from the non-traveling range to the traveling range, the electronic control unit 54 starts the vehicle with respect to the forward clutch 38. It is determined whether or not the clutch is in an area where clutch control is to be executed and in which control mode of the starting clutch control the forward clutch 38 should be controlled. Based on the determination result, the contents of the garage shift control are determined. change.
[0041]
In particular, the electronic control unit 54 determines in which control mode the starting clutch control should be executed based on the traveling state of the vehicle when the traveling state of the vehicle is in the region of the starting clutch control. The garage shift control is performed by controlling the engagement pressure Pclt until the first fill and constant pressure standby shown in FIG. 6A, and then the control shifts to the control of the engagement pressure in the determined control mode.
[0042]
For example, when a garage shift is performed when the vehicle is stopped and the idle switch 66 is ON, the garage shift control shifts to neutral control or creep control, and the vehicle is stopped and the idle switch 66 is OFF. When the garage shift is performed at this time, the garage shift control shifts to the start control.
[0043]
The “neutral control” means that the engagement pressure Pclt of the forward clutch 38 is advanced when the shift lever 28 is in the D range, the idle switch 66 and the brake switch 82 are ON, and the vehicle speed V is 0. In this control, the pressure is controlled so that torque is not transmitted by the clutch.
[0044]
In addition, “creep control” means that the creep torque is reduced when the shift range is in the forward travel range, the idle switch 66 is ON, the vehicle speed V is in the extremely low speed range, and the vehicle acceleration is not negative. In this control, the generated pressure Pcltcrp is used as an instruction oil pressure Pclta to control the engagement pressure Pclt of the forward clutch 38 and to prevent the drive torque of the engine 12 from being transmitted to the drive wheels.
[0045]
In this case, the creep control engagement pressure Pcltcrp is calculated according to the following equation (4). In equation (4), Pcrpb is a basic engagement pressure that generates creep torque, and the forward clutch 38 speed ratio β, that is, the forward clutch 38. Based on the ratio of the input rotational speed Ne to the output rotational speed Ncout, the calculation is performed so that the higher the speed ratio β is, the smaller the speed ratio β is from the map corresponding to the graph shown in FIG. Pcrpl is a pressure that compensates the forward load of the vehicle. For example, based on the forward load Lf of the vehicle based on the inclination angle of the uphill road, the loaded load, the traction amount, and the like estimated in a manner known in the art. The map corresponding to the graph shown in FIG. 8 is calculated so as to increase as the vehicle forward load Lf increases. Further, Pcrpr is a pressure applied when the road surface friction coefficient is estimated to be low in a manner known in the art, and is 0 when the road surface friction coefficient is a normal value.
Pcltcrp = Pcrpb + Pcrpl + Pcrpr (4)
[0046]
“Start control” refers to a situation in which the vehicle speed V is less than or equal to a reference value (positive constant) (very low vehicle speed), the forward clutch 38 is being released, and the idle switch 66 and the brake switch 82 are OFF. In this case, the vehicle is started by controlling the engagement pressure Pclt of the forward clutch 38 to the command hydraulic pressure Pclta calculated by the above equation 3.
[0047]
Further, when the vehicle is running and the vehicle driving region is in the coast control region (the idle switch 66 is ON and the vehicle speed V is equal to or less than a predetermined value), the garage shift control is shifted to coast control, and the vehicle travels. When the traveling state of the car is in the start control region (the idle switch 66 is OFF), the garage shift control is shifted to the start control.
[0048]
“Coast control” means that the vehicle is in a so-called “coast state”, that is, the idle switch 66 is ON and the engine 12 is in a driven state (for example, the differential value Vd of the vehicle speed V is a negative value). In some cases, the speed ratio γ of the belt type continuously variable transmission mechanism 18 is controlled to be the maximum value γmax, and the differential value Vd of the vehicle speed V is set, for example, in synchronization with the control of the continuously variable transmission mechanism 18 Accordingly, the hydraulic pressure of the hydraulic cylinder of the forward clutch 38 is controlled to be reduced, and the transmission of the deceleration torque from the drive wheels to the engine 12 during deceleration braking of the vehicle is suppressed.
[0049]
Further, the electronic control unit 54 determines whether or not the forward clutch 38 is in an engaged state when the vehicle operating region is not in the start clutch control region, and the forward clutch 38 is not in an engaged state. As a general rule, the garage shift control is performed by controlling the engagement pressure Pclt of the forward clutch 38 in the order of first fill, constant pressure standby, sweep-up, and final control shown in FIG. However, when the coast control is terminated due to the increase in the vehicle speed V, the garage shift control is performed by controlling the engagement pressure Pclt of the forward clutch 38 by the sweep-up and final control shown in FIG.
[0050]
Further, the electronic control unit 54 sets the engagement pressure Pclt of the forward clutch 38 to the input torque of the forward clutch when the vehicle operating region is not in the start clutch control region and the forward clutch 38 is engaged. Control accordingly.
[0051]
Although not shown in detail in the figure, the electronic control unit 54 and the engine control unit 68 have a CPU, a ROM, a RAM, and an input / output port unit, which are connected to each other by a bidirectional common bus. And a general configuration including a driving circuit.
[0052]
Next, with reference to the flowchart shown in FIG. 2, the starting clutch control performed by using the forward clutch 38 as the starting clutch in the first embodiment will be described. The starting clutch control according to the flowchart shown in FIG. 2 is started by closing an ignition switch (not shown), and is repeatedly executed every predetermined time.
[0053]
First, in step 10, it is determined whether or not the shift position detected by the shift position sensor 74 is a travel range such as the D range. If an affirmative determination is made, the process proceeds to step 30 and a negative determination is made. When it is performed, that is, when it is determined that the shift position is in the N range or the P range, the start clutch control is terminated in step 20.
[0054]
In step 30, the starting clutch control is performed in one of the control modes of neutral control, creep control, start control, and coast control for the forward clutch 38 based on the vehicle speed V detected by the vehicle speed sensor 64. A determination is made as to whether or not the region is to be executed. If a negative determination is made, the process proceeds to step 80. If an affirmative determination is made, the process proceeds to step 40.
[0055]
In step 40, whether the start clutch control to be executed for the forward clutch 38 based on the vehicle speed V detected by the vehicle speed sensor 64 is a neutral control, creep control, start control, or coast control mode. Determined.
[0056]
In step 50, it is determined whether or not the garage shift control, that is, the control of the engagement pressure of the forward clutch 38 accompanying the garage shift of the shift lever 28 is completed, and if the negative determination is made, the garage shift control is performed. As shown in FIG. 6A, the first fill and constant pressure standby engagement pressure control is executed. When an affirmative determination is made, the forward clutch is operated in the control mode determined in step 40 in step 70. 38 start clutch control is executed.
[0057]
In step 80, for example, is the engagement of the forward clutch 38 completed based on the comparison between the input rotational speed Ne and the output rotational speed Ncout (= Nin) of the forward clutch 38 or the engagement pressure Pclt of the forward clutch 38? When the determination is negative and the determination is affirmative, in step 90, control of the engagement pressure in accordance with the input torque (= output torque of the engine 12) to the forward clutch 38 (Pclta = Pcltt + ΔPclt) is set as the target engagement. The control proceeds to step 100 when a negative determination is made.
[0058]
In step 100, for example, it is determined whether or not the coast control is terminated due to an increase in the vehicle speed V such as when the vehicle is traveling downhill. When the sweep-up and final control shown in FIG. 6C is executed as the garage shift control and a negative determination is made, the first fill shown in FIG. 6B is shown as the garage shift control in step 120. , Constant pressure standby, sweep-up, and final control are executed in this order.
[0059]
Thus, according to the first embodiment shown in the figure, when a garage shift operation is performed by the driver, an affirmative determination is made in step 10, and in step 30, the vehicle operating region starts with respect to the forward clutch 38. When it is determined that the clutch control is in the region where the clutch control is to be executed, step 40 and subsequent steps are executed, and it is determined in step 30 that the vehicle operating region is not in the region where the start clutch control is to be executed for the forward clutch 38. If it is, step 80 and subsequent steps are executed.
[0060]
Therefore, according to the illustrated first embodiment, when the garage shift operation is performed, the garage shift control is performed depending on whether or not the vehicle operating region is in the region where the start clutch control should be executed for the forward clutch 38. Therefore, when the garage shift operation is performed, the engagement pressure of the forward clutch 38 is uniformly increased according to the control to be executed thereafter. It is possible to appropriately control the engagement pressure of the forward clutch 38 by garage shift control.
[0061]
In particular, according to the first embodiment shown in the drawing, when it is determined in step 30 that the vehicle operating region is in the region where the starting clutch control is to be executed for the forward clutch 38, it is executed in step 40. It is determined whether the starting clutch control is in the neutral control mode, the creep control mode, the start control mode, or the coast control mode.
[0062]
If it is determined in step 50 that the garage shift control is not completed, the first fill and constant pressure standby engagement pressure control shown in FIG. 6A is executed as the garage shift control in step 60. When this control is completed, it is determined in step 50 that the garage shift control has been completed, and in step 70, the neutral control, creep control, start control, coast control determined in step 40 above. The starting clutch control is executed in any one of the control modes.
[0063]
Therefore, according to the first embodiment shown in the figure, when the garage shift operation is performed, the engagement pressure control suitable for the subsequent start clutch control is performed by executing the first fill and constant pressure standby engagement pressure control. Therefore, when the garage shift operation is performed, the start clutch control to be executed after that is neutral control, creep control, start, compared to the case where the engagement pressure of the forward clutch 38 is uniformly increased. Even when the control mode is either the control mode or the coast control mode, the transition to the starting clutch control can be performed smoothly.
[0064]
Further, according to the first embodiment, when the vehicle operating region is not in the starting clutch control region and the forward clutch 38 is in the disengaged state, a negative determination is made in steps 30 and 80, and in principle, As in the case of the conventional garage shift control, the first fill, the constant pressure standby, the sweep-up, and the final control shown in FIG. 6B are executed in this order in step 120, but the coast control is performed by increasing the vehicle speed V. When the process is to be completed, an affirmative determination is made in step 100, and in step 120, the sweep-up and final control shown in FIG. 6C are executed as garage shift control.
[0065]
Therefore, for example, in the situation where the forward clutch 38 is in the disengaged state when the coast control is terminated due to the increase in the vehicle speed V when the vehicle is traveling downhill, compared to the case where the garage shift control in step 120 is performed. Thus, the forward clutch 38 can be quickly engaged. In this case, since the driving wheel side clutch plate is rotationally driven by the driving wheel, the difference in rotational speed between the driving wheel side clutch plate and the engine side clutch plate is small, so the forward clutch 38 is quickly engaged. There is no shock caused by
[0066]
Although not shown in the figure, the first fill pressure Pcltf and the time ΔTf in the first garage shift control after the engine 12 is started are set to values larger than the first fill pressure and time in the second transition, respectively. It is preferable. When the temperature Toil of the forward clutch 38 detected by the temperature sensor is low, the first fill time ΔTf is preferably set longer than when the temperature is high.
[0067]
In addition, when a repetitive shift operation (rocking operation) from the R range to the D range and from the D range to the R range is performed, the first fill pressure Pcltf and the engine 12 are quickly transmitted to the drive wheels. The time ΔTf is preferably set to a large value.
[0068]
  First reference example
  This firstoneofReference exampleIn this case, when the shift lever 28 is switched from the travel range such as the D range to the non-travel range by the driver, the electronic control unit 54 controls the forward clutch 38 according to the engagement pressure control routine shown in FIG. The engagement pressure Pclt is controlled.
[0069]
In particular, the electronic control unit 54 engages the forward clutch 38 when the shift lever 28 is switched from the travel range to the non-travel range (N range) when the vehicle is traveling at a high vehicle speed range. The pressure Pclt is not reduced, and the engagement pressure Pclt of the forward clutch 38 is controlled in accordance with the input torque Tcin to the forward clutch 38 as in the case where the shift lever 28 is in the travel range.
[0070]
Further, the electronic control unit 54 is operated when the shift lever 28 is switched from the traveling range to the N range in a situation where the vehicle is traveling at a low vehicle speed range, and an accelerator pedal (not shown) is not depressed. Then, in preparation for switching to the travel range thereafter, the engagement pressure Pclt of the forward clutch 38 is maintained at a pressure that weakly engages the forward clutch 38, and when the accelerator pedal is depressed, the engagement pressure Pclt of the forward clutch 38 is decreased. The pressure is reduced and the forward clutch 38 is released.
[0071]
  NextDepartureFirst clutch controlleroneofReference exampleReferring to FIG. 3 showing the starting clutch control routine in FIG.oneofReference exampleThe starting clutch control in will be described. The starting clutch control according to the flowchart shown in FIG. 3 is also started by closing an ignition switch not shown in the figure, and is repeatedly executed every predetermined time.
[0072]
First, in step 210, it is determined whether or not the shift range detected by the shift position sensor 74 is the P range. If an affirmative determination is made, the process proceeds to step 270, and if a negative determination is made. Proceed to step 220.
[0073]
In step 220, it is determined whether or not the shift range detected by the shift position sensor 74 is the N range. If a negative determination is made, the process proceeds to step 240. If an affirmative determination is made, the process proceeds to step 240. Proceed to 230.
[0074]
In step 230, it is determined whether or not the vehicle speed V is equal to or higher than the reference value Vc, with Vc being a positive constant reference value of, for example, about 50 km / h. The engagement pressure Pclt of the forward clutch 38 is controlled according to the input torque Tcin to the forward clutch 38 with Pclta = Pcltt + ΔPclt as the target engagement pressure, and when a negative determination is made, the routine proceeds to step 250.
[0075]
In step 250, it is determined whether or not the idle switch 66 is in an ON state, that is, whether or not an accelerator pedal not shown in the drawing is depressed by the driver. When the determination is made, the engagement pressure Pclt of the forward clutch 38 is maintained at a constant pressure (pressure for weakly engaging the forward clutch 38) at step 260, and when a negative determination is made, the engagement pressure Pclt of the forward clutch 38 is determined at step 270. When the engagement pressure Pclt is controlled to 0, the forward clutch 38 is released.
[0076]
  Thus this firstoneofReference exampleAccording to the above, when a shift operation from the traveling range to the N range is performed in a situation where the vehicle is traveling at a high vehicle speed range, a negative determination and an affirmative determination are made in steps 210 and 220, respectively. In step 230, the positive determination is made, so that the engagement pressure Pclt of the forward clutch 38 is controlled in accordance with the input torque Tcin to the forward clutch 38 without being reduced in step 240. Thereafter, when the shift operation from the N range to the travel range is performed, the engagement pressure Pclt of the forward clutch 38 is increased by the start control, and the occurrence of shock due to the fluctuation of the torque transmitted by the forward clutch 38 is caused. It can be surely prevented.
[0077]
  Especially in the figureoneofReference exampleAccording to the above, when the vehicle is traveling in the low vehicle speed range, the shift lever 28 is switched from the traveling range to the N range, and when an accelerator pedal not shown in the drawing is not depressed, Since the engagement pressure Pclt of the forward clutch 38 is held at a constant pressure that weakly engages the forward clutch 38 in preparation for switching to the travel range, the engagement pressure Pclt of the forward clutch 38 is controlled to 0 and the forward clutch 38 is released. Compared with the case where it is done, the engagement pressure of the forward clutch 38 can be controlled with good responsiveness when the shift operation to the travel range is subsequently performed.
[0078]
  Also shown in the figureoneofReference exampleWhen the shift lever 28 is switched from the traveling range to the N range in a situation where the vehicle is traveling in the low vehicle speed range, and the accelerator pedal (not shown) is depressed, the forward clutch 38 is operated. Since the engagement pressure Pclt is reduced and the forward clutch 38 is released, torque transmission by the forward clutch 38 can be prevented to reliably prevent the rotational speed Ne of the engine 12 from being excessively reduced. The durability of the forward clutch 38 can be improved.
[0079]
  Second embodiment
  FIG. 4 is a flowchart showing an engagement pressure control routine when the start clutch control mode shifts to control for increasing the start clutch engagement pressure in the first embodiment. The engagement pressure control according to the flowchart shown in FIG. 4 is executed as part of step 70 in the first embodiment described above, for example.
[0080]
First, at step 310, it is determined whether or not the control mode is the transition to the control mode of the starting clutch control and the control is to shift to the control for increasing the engagement pressure Pclt of the forward clutch 38, and the negative determination is made. If YES, the process proceeds to step 350. If an affirmative determination is made, the process proceeds to step 320.
[0081]
In step 320, it is determined whether or not the first fill is being executed. If an affirmative determination is made, it is stored in step 330 that the process has shifted to another control mode during the execution of the first fill. When a negative determination is made, the first fill pressure Pcltf and the time ΔTf are calculated in step 340, the first fill is executed, and a timer for managing the elapsed time of the first fill is started.
[0082]
In this case, the first fill pressure Pcltf and the time ΔTf are such that the lower the clutch oil temperature Toil detected by the temperature sensor, the higher the first fill pressure Pcltf and the time ΔTf. It is variably set according to Toil.
[0083]
In step 350, it is determined whether or not the first fill is being executed. When a negative determination is made, the control according to the routine shown in FIG. 4 is temporarily terminated and an affirmative determination is made. Sometimes go to step 360.
[0084]
In step 360, it is determined whether or not the current control mode has been shifted to another control mode during the first fill. If an affirmative determination is made, the process proceeds to step 380, where a negative determination is made. If YES, go to step 370.
[0085]
In step 370, it is determined whether or not a predetermined time (time ΔTf calculated for the current control mode) has elapsed since the start of the starting clutch control in the current control mode, and a negative determination is made. If it is determined, the control by the routine shown in FIG. 4 is once ended, and if an affirmative determination is made, the routine proceeds to step 390.
[0086]
In step 380, it is determined whether or not a predetermined time (time ΔTf calculated for the control mode before the transition) has elapsed since the start of the starting clutch control in the control mode before the transition, and a negative determination is made. When it is performed, the control according to the routine shown in FIG. 4 is once terminated, and when an affirmative determination is made, the first fill is terminated and the timer is stopped at step 390.
[0087]
  Thus this firsttwoAccording to the embodiment, the first fill pressure Pcltf and the time ΔTf are variably set in step 340 according to the clutch oil temperature Toil so as to increase as the clutch oil temperature Toil of the forward clutch 38 decreases. Therefore, even in a situation where the temperature Toil of the clutch oil is low and the responsiveness of the hydraulic control device 39 is low, the engagement pressure Pclt of the forward clutch 38 can be controlled with good responsiveness.
[0088]
  Also shown in the figuretwoAccording to the embodiment, during the first fill, for example, when the first fill is executed by the transition of the control mode to the start control during the first fill at the transition from the neutral control to the creep control. When fast fill is executed in accordance with the transition to another control mode, the first fill time ΔTf in the subsequent control mode is controlled based on the start point of the first fill in the previous control mode. Can be prevented from being executed unnecessarily long, and the subsequent engagement pressure Pclt of the forward clutch 38 can be controlled with good responsiveness.
[0089]
  Second reference example
  FIG.oneofReference example3 is a flowchart showing an engagement pressure control routine when the starting clutch control mode shifts to neutral control. Note that the engagement pressure control according to the flowchart shown in FIG.oneofReference exampleAs part of step 260 in FIG.
[0090]
First, in step 410, it is determined whether or not neutral control is started for the forward clutch 38. If a negative determination is made, the process proceeds to step 480, and if an affirmative determination is made, the process proceeds to step 480. Proceed to 420.
[0091]
In step 420, it is determined whether or not the previous control mode was garage shift control. If an affirmative determination is made, the process proceeds to step 450. If a negative determination is made, the process proceeds to step 430.
[0092]
In step 430, it is determined whether or not the previous control mode was creep control. If a negative determination is made, in step 440, the control mode of the engagement pressure Pclt of the forward clutch 38 (see FIG. 9). ) Is set to mode c, and when an affirmative determination is made, the routine proceeds to step 450.
[0093]
In step 450, it is determined whether or not the engagement pressure Pclt of the forward clutch 38 is higher than a set value Pclta (a positive constant larger than Pclto). If an affirmative determination is made, the process proceeds to step 460. When the control mode for the engagement pressure of the forward clutch 38 is set to mode a and a negative determination is made, at step 470, the control mode for the engagement pressure of the forward clutch 38 is set to mode b.
[0094]
In step 480, it is determined whether or not the neutral control is being executed for the forward clutch 38. If a negative determination is made, the control by the routine shown in FIG. If yes, go to step 490.
[0095]
In step 490, it is determined whether or not the engagement pressure control mode of the forward clutch 38 is mode c. If an affirmative determination is made, in step 500, the engagement pressure PClt of the forward clutch 38 is determined. Is controlled by feedback control of neutral control, for example, PID control for making the speed ratio β of the forward clutch 38 constant.
[0096]
In step 510, it is determined whether or not the control mode of the engagement pressure of the forward clutch 38 is mode a. If an affirmative determination is made, the engagement pressure Pclt of the forward clutch 38 is determined in step 520. Is quickly reduced to the set pressure Pclta, and then swept down to a second set pressure Pcltb (a positive constant smaller than Pclta and substantially the same as Pclto) with a predetermined depressurization gradient ΔPcltc (negative constant). When the control is performed by the feedback control of the post-neutral control and a negative determination is made, in step 530, the engagement pressure Pclt of the forward clutch 38 is swept down to the second set pressure Pcltb with a predetermined pressure decrease gradient ΔPcltc. It is controlled by feedback control of post-neutral control.
[0097]
  Thus this firsttwoofReference exampleTherefore, when the garage shift control shifts to the neutral control, an affirmative determination is made at steps 410 and 420, respectively, and when the creep control shifts to the neutral control, an affirmative determination is made at step 410. At the same time, a negative determination is made at step 420 and then an affirmative determination is made at step 430. When the engagement pressure Pclt of the forward clutch 38 is higher than the set value Pclta, the forward clutch 38 is turned off at step 460. When the engagement pressure control mode is set to mode a and the engagement pressure Pclt is equal to or lower than the set value Pclta, the engagement pressure control mode of the forward clutch 38 is set to mode b in step 470.
[0098]
Therefore, as shown in FIG. 9A, when the engagement pressure Pclt of the forward clutch 38 when shifting from the garage shift control or the creep control to the neutral control is higher than the set value Pclta, the engagement pressure Pclt is first set. Since the pressure is quickly lowered to the set pressure Pclta and then swept down to the second set pressure Pcltb at a predetermined pressure reduction gradient ΔPcltc, the engagement pressure is independent of the engagement pressure Pclt when the control mode is shifted. As compared with the case where the is swept down, the transition to the feedback control of the neutral control can be promptly performed without generating a shock.
[0099]
As shown in FIG. 9B, when the engagement pressure Pclt of the forward clutch 38 at the time of shifting from the garage shift control or the creep control to the neutral control is equal to or less than the set value Pclta, the second set pressure Pcltb Therefore, it is possible to reliably prevent the occurrence of a shock due to a sudden change in the engagement pressure.
[0100]
As shown in FIG. 9C, when the coast control is shifted to the neutral control, the engagement pressure Pclt of the forward clutch 38 is a pressure in the vicinity of Pcltb. No quick down or sweep down is performed, and the control shifts directly to the neutral control feedback control.
[0101]
Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to the above-described embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art.
[0102]
For example, in the first embodiment described above, it is determined in step 30 that the vehicle operating region is not in the starting clutch control region, and in step 80 the starting clutch 38 is not engaged. When the determination is made, the content of the garage shift control is changed by the determination in step 100, but steps 100 and 110 may be omitted.
[0103]
  Each of the above-described embodimentsAnd reference examplesIn this case, the forward clutch 38 as a start clutch is provided between the engine 12 as a drive source and the continuously variable transmission mechanism 18 as a transmission, but the start clutch is provided between the transmission and the drive wheel. In this case, the above equation 1 is replaced by the following equation 5 where γ is the transmission gear ratio.
    Pcltt = (α · Tcltt · γ + W) / A (5)
[0104]
  Each of the above-described embodimentsAnd reference examplesIn this case, the starting clutch is the forward clutch 38 of the forward / reverse switching device 16, but the starting clutch is provided between the engine 12 and the forward / reverse switching device 16 independently of the forward clutch 38 of the forward / reverse switching device 16. It may be provided between the machine and the drive wheel.
[0105]
  Each of the above-described embodimentsAnd reference examplesIn this case, the transmission mechanism is a belt-type continuously variable transmission mechanism 18, but the transmission mechanism is any continuously variable transmission mechanism known in the art such as a toroidal cone type continuously variable transmission mechanism. The transmission may be an automatic transmission, and particularly when the transmission is an automatic transmission, the start clutch may be a start clutch of the automatic transmission.
[Brief description of the drawings]
FIG. 1 is a skeleton diagram showing a vehicle power transmission device to which an embodiment of a starting clutch control device according to the present invention is applied.
FIG. 2 is a flowchart showing a start clutch control routine performed using the forward clutch shown in FIG. 1 as a start clutch.
[Fig. 3]DepartureFirst clutch controlleroneofReference example7 is a flowchart showing a starting clutch control routine in FIG.
FIG. 4 is a flowchart showing an engagement pressure control routine when the start clutch control mode shifts to control for increasing the start clutch engagement pressure in the first embodiment.
FIG. 5oneofReference example3 is a flowchart showing an engagement pressure control routine when the starting clutch control mode shifts to neutral control.
FIG. 6 shows a control pattern of the engagement pressure Pclt of the forward clutch 38 in the garage shift control, (A) shows the first fill and constant pressure standby engagement pressure control, (B) shows the first fill, Engagement pressure control for constant pressure standby, sweep up, and end control is shown, and (C) shows engagement pressure control for sweep up and end control.
FIG. 7 is a graph showing the relationship between the speed ratio β of the forward clutch 38 and the basic engagement pressure Pcrpb for creep control.
FIG. 8 is a graph showing a relationship between a vehicle forward load Lf and a pressure Pcrpl for compensating the vehicle forward load.
FIG. 9 shows a control mode of the engagement pressure Pclt when the control mode of the forward clutch 38 shifts to neutral control. FIG. 9A shows a case where the engagement pressure Pclt at the time of shift is higher than the set pressure Pclta. (B) shows a case where the engagement pressure Pclt at the time of transition is lower than the set pressure Pclta and higher than the second set pressure Pcltb, and (c) shows a case where the coast control is shifted to the neutral control. .
[Explanation of symbols]
        12 ... Engine
        14 ... Torque converter
        16 ... Forward / reverse switching device
        18 ... Belt type continuously variable transmission mechanism
        28 ... Shift lever
        39, 52 ... Hydraulic control circuit
        54 ... Electronic control unit
        60 ... Rotation speed sensor
        62 ... Throttle opening sensor
        64 ... Vehicle speed sensor
        66 ... Idle switch
        68. Engine control device
        72 ... Rotational speed sensor
        74: Shift position sensor
        76 ... Torque sensor
        78 ... Pressure sensor
        80 ... Temperature sensor
        82 ... Brake switch

Claims (2)

In the based have been bidding Gosuru starting clutch control device shift position of the shift lever starting clutch provided in a power transmission path for transmitting the power without using more fluid torque converter to the drive wheels engine, than the non-travel position Until the control of the engagement pressure of the starting clutch accompanying the shift operation to the running position is completed, torque transmission to the starting clutch can be performed by controlling the engagement pressure of the starting clutch in the first fill and constant pressure standby. After the control of the engagement pressure of the start clutch accompanying the shift operation from the non-travel position to the travel position is completed, the start clutch is engaged according to the control mode. A starting clutch control device characterized by controlling to a state. In the based have been bidding Gosuru starting clutch control device shift position of the shift lever starting clutch provided in a power transmission path for transmitting the power without a fluid torque converter to the drive wheels from the engine, the operating area of the vehicle there is judged whether the starting clutch control region, when the operating range of the vehicle is determined to be in the starting clutch control area, of the starting clutch due to the shift operation to the non-driving position by Rihashi row position Until the control of the engagement pressure is completed, the start clutch is maintained in the non - engagement state immediately before torque transmission becomes possible by controlling the engagement pressure of the start clutch in the first fill and constant pressure standby. after the control of the engaging pressure of the starting clutch due to the shift operation of the travel position from the traveling position is completed, control the starting clutch in the engaged state in accordance with the control mode Starting clutch control apparatus which is characterized in that.

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