JP3557935B2 - Control device for automatic transmission for vehicles - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control apparatus for an automatic transmission for a vehicle, which automatically switches the shift speed of the automatic transmission for a vehicle, and in particular, suppresses a shift shock that is likely to occur in an engine brake range when a predetermined gear is established. It is about technology.
[0002]
[Prior art]
In the automatic transmission for a vehicle, a gear selected from a plurality of gears is established by a combination of operations of the plurality of hydraulic friction engagement devices. Normally, in a non-engine brake range such as a D range, a predetermined gear stage achieved by engagement of one hydraulic friction engagement device is, for example, an engine brake range in an engine brake range such as an L range or an L range. This is achieved by adding an element for generating an effect and engaging a plurality of hydraulic friction engagement devices.
[0003]
[Problems to be solved by the invention]
However, in the control device of the conventional automatic transmission for a vehicle as described above, the shift transient hydraulic pressure of the hydraulic friction engagement device for achieving the predetermined gear position is common regardless of the travel range, so that the non-engine As compared with the case of the brake range, the number of hydraulic friction engagement devices to be engaged in the engine brake range is increased and the total engagement torque is increased, so that the shift shock is increased and the shift feeling is impaired. There was a disadvantage.
[0004]
The present invention has been made in view of the above circumstances, and an object of the present invention is to control an automatic transmission for a vehicle in which a shift shock is suppressed when the predetermined gear is achieved even in an engine brake range. It is to provide a device.
[0005]
[Means for Solving the Problems]
The gist of the present invention to achieve this object is to establish a predetermined gear in an automatic transmission for a vehicle in which a gear is selected by a combination of operations of a plurality of hydraulic friction engagement devices. In the non-engine brake range, the first hydraulic friction engagement device is engaged, and in the engine brake range, the second hydraulic friction engagement device is engaged in addition to the first hydraulic friction engagement device. A control device for controlling the first hydraulic friction engagement device in the engine brake range under the same engine load or an input torque of an automatic transmission when upshifting to the predetermined gear position; And a shift transient hydraulic pressure control means for lowering the shift transient hydraulic pressure of the engine during the non-engine brake range.
[0006]
【The invention's effect】
With this configuration, the shift transient hydraulic pressure control means performs the first shift in the engine brake range when the upshift to the predetermined gear stage is performed under the same engine load or the same input torque of the automatic transmission. Since the shift transient hydraulic pressure of the friction engagement device is lower than that in the non-engine brake range, the engagement of the first hydraulic friction engagement device and the engagement of the second hydraulic friction engagement device in the engine brake range is also effective. In achieving the above-mentioned predetermined gear, a shift shock is suppressed.
[0007]
Other aspects of the invention
Preferably, the first hydraulic friction engagement device and the second hydraulic friction engagement device are respectively connected to accumulators for applying a line pressure as a back pressure, and the non-engine brake In a gear shift period to achieve the predetermined gear in the range, the shift transient hydraulic pressure control means reduces the line pressure as compared with an engine brake range. According to this configuration, there is an advantage that control is simplified and reliability is increased as compared with a case where the engagement pressures of the first hydraulic friction engagement device and the second hydraulic friction engagement device are directly controlled. .
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0009]
FIG. 1 shows a torque converter 12 connected to an engine 10 of a vehicle, an automatic transmission 14, a differential gear device 16, a hydraulic control device for controlling a shift speed of the automatic transmission 14, that is, a hydraulic control circuit 18, A shift electronic control device 20 for controlling the control circuit 18 and the like are shown. Power output from the engine 10 is transmitted to drive wheels (not shown) via the torque converter 12, the automatic transmission 14, the differential gear device 16, the left and right axles 22 and 24, and the like.
[0010]
The torque converter 12 is connected to a pump impeller 28 connected to the crankshaft 26 of the engine 10 and an input shaft 30 of the automatic transmission 14 and receives power from the pump impeller 28 via fluid. A lock-up clutch 40 for directly connecting the turbine wheel 32, a fixed wheel 38 fixed to a position-fixed housing 36 via a one-way clutch 34, and a pump wheel 28 and the turbine wheel 32 via a damper (not shown). And
[0011]
The automatic transmission 14 is a multi-stage transmission that achieves four forward gears and one reverse gear, and includes the input shaft 30, a set of Ravigneaux-type planetary gear devices 44, and a Ravigneaux-type planetary gear device. A ring gear 48 that rotates together with a ring gear 46 of 44 and functions as an output shaft that outputs driving force from the engine 10 to the differential gear device 16 or transmits power between the ring gear 48 and the differential gear device 16. And a counter shaft 50.
[0012]
In the Ravigneaux type planetary gear set 44, a single pinion planetary gear set 52 and a double pinion planetary gear set 54 share a carrier 56 and the ring gear 46. The single pinion planetary gear device 52 includes a sun gear 58, a planetary gear 60 attached to the carrier 56, and the ring gear 46. The double pinion planetary gear 54 includes a sun gear 62, a first pinion gear 64 and a second pinion gear 66 that are integrally connected to each other and rotatably attached to the carrier 56.
[0013]
Some of the components of the single pinion planetary gear set 52 and the double pinion planetary gear set 54 are not only integrally connected to each other but also selectively connected to each other by three clutches C1, C2, and C3. It has become. Some of the components of the single pinion planetary gear set 52 and the double pinion planetary gear set 54 are selectively connected to the housing 36 by three brakes B1, B2, and B3. Is engaged with the housing 36 by two one-way clutches F1 and F2 in the rotation direction. In addition, since parts other than the counter shaft 50 of the torque converter 12 and the automatic transmission 14 are configured symmetrically with respect to the axis of the input shaft 30 and the like, in FIG. The lower side is omitted.
[0014]
The clutches C1, C2, C3 and the brakes B1, B2, B3, which are hydraulic friction engagement devices, are, for example, multi-plate clutches or band brakes having one or two bands with opposite winding directions. The frictional engagement and the disengagement thereof are respectively controlled by the hydraulic control circuit 18 which operates according to a command from the electronic control unit 20 for shifting, so that the gear ratio γ as shown in FIG. (= The number of rotations of the input shaft 30 / the number of rotations of the counter shaft 50) can be obtained with four forward speeds and one reverse speed. “1ST”, “2ND”, “3RD”, and “4TH” in FIG. 2 respectively represent a first gear, a second gear, a third gear, and a fourth gear on the forward side. The gear ratio γ gradually decreases from the first gear to the fourth gear. In FIG. 2, “P”, “R”, “N”, “D”, “2”, and “L” are parking (P) ranges that are selectively selected by manual operation of the shift lever 84. , Reverse (R) range, neutral (N) range, drive (D) range, second (2) range, and low (L) range, respectively. The P range and the N range are non-travel ranges selected when the vehicle is not driven, and the R range, the D range, the 2 range, and the L range are travel ranges for moving the vehicle backward or forward. The two ranges and the L range are also engine brake ranges because they not only increase the driving force of the vehicle but also generate engine brakes.
[0015]
In FIG. 2, a mark “○” indicates an engaged or operating state, and a mark “X” indicates a released or non-operating state. In order to achieve the predetermined gear, that is, the second gear, the clutch C1 and the brake B2 are only engaged in the non-engine brake range D, whereas the engine brake ranges 2 and L are set. In the range, the brake B1 is further engaged in addition to the clutch C1 and the brake B2.
[0016]
The hydraulic control circuit 18 has three solenoid valves SV1 to SV3 used for controlling the gear position of the automatic transmission 14 and the like, and a size corresponding to a throttle opening TA detected by a throttle opening sensor 76 described later. the control oil pressure P the linear solenoid valves _S generates SLT, for example, frictional engagement of the lock-up clutch 40, the linear solenoid valve SLU for generating a hydraulic pressure for control of such release and slippage of the frictional engagement, and An oil temperature sensor 88 and the like functioning as a hydraulic oil temperature detecting device for detecting the hydraulic oil temperature T _OIL of the hydraulic oil in the hydraulic control circuit 18 is provided.
[0017]
The shift electronic control device 20 is a so-called microcomputer including a CPU 70, a RAM 72, a ROM 74, an input / output interface (not shown), and the like. The microcomputer includes an opening of a throttle valve provided in an intake pipe (not shown) of the engine 10. a throttle opening sensor 76 for detecting the TA, the input for detecting the rotational speed _{N iN} of the engine rotational speed sensor 78 for detecting the rotational speed _{N E} of the engine 10, the rotational speed _{N T} that is, the input shaft 30 of the turbine wheel 32 axial rotation speed sensor 80, a vehicle speed sensor 82 for detecting the rotational speed _{N C} i.e. the vehicle speed V of the counter shaft 50, the operating position i.e. L of the shift lever 84, S, D, N, R, either the P range The operating position sensor 86 for detecting the operating oil temperature and the oil temperature sensor 88 for detecting the operating oil temperature in the hydraulic control circuit 18 provide Signal representing the torque angle TA, signals indicative of engine rotational speed _N E (r.p.m.), a signal representing the input shaft speed _N IN (r.p.m.), the output shaft rotational speed _N C ( r.p.m.) that signal representing the vehicle speed V, the signal representing the operating position _{P ST} of the shift lever 84, a signal representative of the working oil temperature _{T oIL} of the hydraulic control circuit 18 are supplied. The CPU 70 of the shift electronic control device 20 processes the input signal using the RAM 72 according to a program stored in the ROM 74 in advance, and based on the processing result, for example, detects the traveling state of the vehicle, The control of SV1 to SV3, the linear solenoid valves SLT and SLU, and the like are executed.
[0018]
FIG. 3 is a diagram schematically illustrating a configuration of a main part of the hydraulic control circuit 18. 3, the original pressure generating device 90, the line pressure P _L that by regulating the value corresponding to the engine load pressure of the hydraulic fluid pumped from a hydraulic pump 92 rotationally driven by the engine 10, the hydraulic The frictional engagement devices C1, C2, C3, B1, B2, and B3 output the original pressure to the shift valve device 94 and the like. Manual valve 96 has been mechanically connected to the shift lever 84, by switching the line pressure P _L in response to the travel range selecting operation of the shift lever 84, to a selected running range The corresponding oil pressure, for example, R range pressure, D range pressure, 2 range pressure, L range pressure is output to shift valve device 94. Also, the solenoid on-off valves SV1 and SV2 are operated by the electronic shift control device 20 exclusively for selecting a gear position, and thereby output a signal pressure to the shift valve device 94.
[0019]
The shift valve device 94 is operated to switch at the time of gear shifting based on a hydraulic pressure corresponding to a travel range from the manual valve 96 and a hydraulic signal from the two first and second solenoid on-off valves SV1 and SV2. It is provided with a 2-shift valve, a 2-3 shift valve, a 3-4 shift valve, etc., and applies hydraulic pressure to each of the hydraulic friction engagement devices C1, C2, C3, B1, B2, B3 according to the operation shown in FIG. Is selectively supplied. Of the hydraulic friction engagement devices C1, C2, C3, B1, B2, B3, the clutches C1, C2, C3 and the brakes B1, B2 are used to alleviate an increase in the engagement hydraulic pressure, that is, the engagement torque. , The C1 accumulator A _C1 , the C2 accumulator A _C2 , the C3 accumulator A _C3 , the B1 accumulator A _B1 , and the B2 accumulator A _B2 are connected to each other. And the C1 accumulator _{A C1} and B1 accumulator _{A B1,} in the above C2 accumulator _A C2, C3 accumulator _{A C3,} and B2 accumulator _{A B2} is the line pressure _{P L} which can be varied by a command from the shift electronic control unit 20 The shift pressure is supplied as the accumulating back pressure, and shift transition control for adjusting the engagement hydraulic pressure of each hydraulic friction engagement device during the shift transition period is performed.
[0020]
The flow resistance between the shift valve device 94 and the clutches C1 and C1 accumulator A _C1 is determined based on the hydraulic pressure signal from the third solenoid on-off valve SV3 and the engagement pressure P _{B1 of the} brake B1. An orifice switching valve including a plurality of oil passages provided with orifices and an oil passage switching valve switching the plurality of oil passages for adjusting the engagement timing or the release timing of the clutch C1 according to the vehicle state by switching. A device 98 is provided. Since the engagement pressure P _{B1 of the} brake B1 is applied to the orifice switching valve device 98, the rise and fall of the engagement pressure P _C1 of the clutch C1 are caused by the fall and fall of the engagement pressure P _B1 of the brake B1. It is controlled in relation to the rise. For example, in the 4 → 3 downshift, the hydraulic fluid in the release-side brake B1 and the B1 accumulator A _B1 flows out. However, while the engagement pressure P _B1 is high, the orifice switching valve device 98 allows the hydraulic fluid to flow to the clutch C1. Hydraulic oil is supplied promptly after the resistance is reduced. However, when the hydraulic oil falls below a predetermined value, the flow resistance is increased and the engagement pressure PC1 of the clutch _C1 is slowly increased.
[0021]
4, the out of the hydraulic control circuit 18 is a diagram explaining in detail the original pressure generator 90 for generating a line pressure P _L as the original pressure of the hydraulic fluid supplied to the clutch C1 and the brake B1, etc. . In FIG. 4, the hydraulic pump 92 is rotationally driven by the engine 10 and sucks the recirculated hydraulic oil through the strainer 100 to pump it to the line pressure regulating valve 102.
[0022]
The line pressure regulating valve 102 includes a plunger 110, a spool valve element 112 that is provided to be movable in the axial direction while being in contact with the plunger 110, and opens and closes between an input port b and an output port d. A spring 116 for urging the valve element 112 in the valve closing direction via a spring receiving plate 114, and the hydraulic pressure of the hydraulic oil from the hydraulic pump 92 supplied to the input port b of the valve 116 is supplied to the linear solenoid valve SLT. from, based on the control oil pressure P _S is supplied to the input port a, pressure load or regulated to a line pressure P _L having a size corresponding to the input torque of the automatic transmission 14 of the engine 10. The input port c of the line pressure regulating valve 102 is supplied with the hydraulic pressure of the input port b as a feedback hydraulic pressure. The urging force of the spring 116 is W _REG , the area of the annular pressure receiving surface of the land 118 of the spool valve 112 is A _REG1 , and the pressure of the plunger 110 urges the spool valve 112 in the valve closing direction of the output port d. if the area of the surface and _{a REG2,} the line pressure _{P L} is represented by the following formula (1). Here, (1) indicates that the line oil pressure P _L is generated in proportion to the control oil pressure P _S. When the control oil pressure P _S is typically representative of the magnitude of the input torque T _IN of the engine load, or the automatic transmission 14, the line pressure P _L is necessary to the extent that sliding of hydraulic friction engagement device does not occur and a value sufficient to become the engine load, or are pressure adjusted to normal pressure value of a size corresponding to the magnitude of the input torque T _iN of the automatic transmission 14.
[0023]
(Equation 1)
_{P L = (A REG2 / A} REG1) · P S + W REG / A REG1 ··· (1)
[0024]
The linear solenoid valve SLT includes a spool valve 120 that opens and closes between an input port a and an output port b, and a spring 122 that urges the spool valve 120 in a valve opening direction. The aforementioned input port a, a constant pressure P _SOL is supplied, the control as a hydraulic whose constant pressure P _SOL is pressure regulated in response to the exciting current output from the shift electronic control unit 20 to the linear solenoid S _SLT hydraulic P _S is generated at the output port b. The urging force for urging the spool valve element 120 in the valve closing direction of the output port b in accordance with the exciting current of the linear solenoid S _SLT is F _I , the urging force of the spring 122 is W _SLT , _Assuming that the area of the annular pressure receiving surface of the land 124 is A _SLT , the oil chamber 128 between the land 124 and the land 126 and the output port b are communicated by the oil passage 130, and the annular shape of the land 124 since hydraulic pressure acting on the pressure receiving surface has a the control oil pressure P _S, the control oil pressure P _S is expressed by equation (2).
[0025]
(Equation 2)
_{P S = W SLT / A SLT} -F I / A SLT ··· (2)
[0026]
In FIG. 4, the pressure reducing valve 132 includes a spool valve 136 that opens and closes between an input port a and an output port b, and a spring 138 that urges the spool valve 136 in a valve opening direction. the line pressure P _L supplied to a, and by regulating the above constant pressure P _SOL is generated to the output port b, the linear solenoid valve SLT, and supplies the like the linear solenoid valve SLU. The input port c of the pressure reducing valve 132 is supplied with the hydraulic pressure of the output port b as a feedback hydraulic pressure. If the pressure receiving area communicating with the input port c of the spool valve element 136 is A _MOD , and the biasing force of the spring 138 is W _MOD , the constant pressure P _SOL is equal to the constant pressure represented by the equation (3). Become.
[0027]
(Equation 3)
P _SOL = W _MOD / A _MOD (3)
[0028]
FIG. 5 is a functional block diagram illustrating a main control function of the electronic control unit 20 for shifting. In FIG. 5, the shift control means 142 determines the vehicle speed V, the throttle opening TA, and the fuel injection amount F obtained from the vehicle speed sensor 82 from a shift diagram previously selected in response to the travel range selection operation of the shift lever 84. Shift point control for determining a shift of the automatic transmission 14 and outputting a shift command based on an engine load represented by any of an intake air amount Q and an accelerator pedal operation amount, and a shift of the automatic transmission 14 During the period, the degree of shift is determined based on the vehicle speed V, and shift transient control for improving the shift feeling by transiently controlling the engagement oil pressure of the hydraulic friction engagement device involved in the shift is executed. I do.
[0029]
That is, in the shift point control, in the two-dimensional coordinates including the vehicle speed axis representing the actual vehicle speed V and the engine load axis representing the engine load, the point representing the actual vehicle speed V and the engine load traverses the shift line. A shift determination is made based on which of the gear positions divided by the shift line has been entered. For example, when the point representing the actual vehicle speed V and the engine load crosses, for example, the 1 → 2 upshift line toward the high vehicle speed side, the 1 → 2 upshift is determined. Also, in the above-described shift transient control, for example, as shown in FIG. 6, the shift is controlled so that the engagement of the brake B2 involved in the 1 → 2 upshift is smoothly performed within the 1 → 2 upshift period. hydraulic raise the engagement pressure P _B2 of the brake B2 in accordance with the degree of progression of is basically formed. Then, it is determined whether or not the actual input shaft rotation speed N _IN has been synchronized with the input shaft rotation speed (G ₂ × N _O where G ₂ is the gear ratio of the second speed gear stage) after the establishment of the second speed gear stage. judgment, if it is determined terminates the maximum value (= P _L) as a 1 → 2 upshift controlling engagement pressure P _C2 of the clutch C2 after a predetermined time.
[0030]
The line pressure control means 144 uses a guard pressure determination means (not shown) based on the input shaft torque T _IN, that is, the turbine torque T _T , so as not to cause slippage in other hydraulic friction engagement devices engaged during gear shifting. the linear solenoid valve SLT so as to output the line pressure P _L of the same pressure or the same size as the pressure obtained by adding a margin value alpha thereto (P _{LGRD +} α) and the guard pressure P _LGRD determined from the line pressure regulating valve 102 Te Drive. Further, during the shift period, the line pressure control unit 144 does not _drop below the guard pressure P _LGRD based on a command from the learning control unit (not shown) or the shift transient hydraulic control unit 150 described later for the shift transient control. changing the line pressure P _L in the range, the engagement pressure P _C1 of the clutch C1 is 1 → 2 upshift engagement application pressure for example 2 range of hydraulic friction engagement devices involved in the _shift, the engagement pressure P of the brake B1 _B1, and controls the engagement pressure _{P B2} of the brake B2.
[0031]
The travel range determination means 146 determines whether the travel range selected by operating the shift lever 84 is the D range which is a non-engine brake range, the 2 range which is an engine brake range, or the L range, or not. Is determined based on the signal from The shift determining means 148 determines whether or not the shift is such that the number of hydraulic friction engagement devices for establishing the gear after the shift increases when the shift is in the 2, L range, compared to when the shift is in the D range. For example, the number of brakes for establishing the second gear is increased when the gear is in the 2, L range compared to when the gear is in the D range. It is determined whether there is a 1 → 2 upshift from the first gear to the second gear.
[0032]
The shift transient hydraulic pressure control means 150 determines that the traveling range determination means 146 determines that the engine brake range is the two range or the L range, and that the shift determination means 148 determines that the 1 → 2 upshift has been performed. it is within that 1 → 2 upshift period, by lowering only the predetermined pressure back pressure (= _{P L)} of to B1 accumulator _{a B1} and B2 accumulator _{a B2} compared to the case where the D-range, in FIG. 6 As shown by the two-dot chain line, the shift transient hydraulic pressure of the brakes B1 and B2 is reduced. The linear solenoid valve SLT is provided with a measurement driving signal D _SLT indicating the drive current or Diyuti ratio as shown in FIG. 7 outputs a control signal P _S becomes smaller as increasing. For this reason, the shift transient hydraulic control means 150 sets the drive signal _{DSLT as} the input torque T _IN (turbine torque T _T ) of the automatic transmission 14 increases with the travel range as a parameter, as shown in FIG. 8, for example. By determining and outputting the drive signal _DSLT which is increased in comparison with the case of the D range from the decreasing relationship, as shown in FIG. 9, the B1 accumulator A _B1 is compared with the case of the D range. and B2 accumulator _{a B2} of back pressure is to low (= _{P L)} only predetermined pressure.
[0033]
Hereinafter, a main part of the control operation of the shift electronic control device 20 will be described with reference to FIG. FIG. 10 shows a 1 → 2 shift transient hydraulic control routine.
[0034]
10, at SA1 corresponding to the shift determining means 148, it is determined whether or not the shift control means 142 has determined the power-on 1 → 2 shift. If the determination in SA1 is denied, this routine is terminated. If the determination is affirmed, in SA2 corresponding to the traveling range determination means 146, whether the 2 range or the L range has been selected by the shift lever 88. It is determined whether or not. If the determination of SA2 is denied, in SA3, the size for establishing the second gear in the D range, that is, the second gear is improved with a high responsiveness only by engagement of one brake B2. In order to obtain the back pressure (= P _L ) of the B2 accumulator A _{B2 in} order to obtain the engagement pressure P _B2 of the brake B2, which is the transient hydraulic pressure during the 1 → 2 shift period, so as to have a value that can be satisfied smoothly. The non-engine brake range drive signal _DSLT is determined and output from FIG.
[0035]
However, when the determination of SA2 is affirmative, for example, it is a case where the 1 → 2 shift is determined in a state where the shift lever 88 is operated to the 2 or L range, so that the engagement of the two brakes B1 and B2 is determined. In order to obtain the engagement pressure P _B2 of the brake B2, which is the transient hydraulic pressure in the 1 → 2 shift period in which the second gear stage is established without the shift shock in the combined case, the back pressure (= P _L ) of the B2 accumulator A _B2 is obtained. Drive signal _DSLT for the engine brake range is determined and output from FIG. As apparent from FIG. 8, the drive signal _DSLT for the engine brake range has a larger value than the drive signal _DSLT for the non-engine brake range, while the characteristic of the linear solenoid valve SLT is shown in FIG. since smaller control pressure P _S with increasing driving signals D _SLT as shown in is intended to be output, as shown in two-dot chain line in FIG. 6, in the 1 → 2 shift period when the engine brake B2 engagement pressure _{P B2} of the back pressure and the brake B2 of the accumulator _{a B2} is lower than the engagement pressure _{P B2} of the back pressure and the brake B2 of the B2 accumulator _{a B2} of when the engine brake.
[0036]
As described above, according to this embodiment, the shift transient hydraulic pressure control means 150 (SA4) reduces the engagement pressure P _B2 of the brake B2 in the engine brake range during the 1 → 2 shift period, that is, the shift transient hydraulic pressure. Since it is lower than that in the range, the shift shock is preferably suppressed when achieving the second gear by engagement of the brake B1 and the brake B2 in the 1 → 2 shift of the engine brake range. .
[0037]
Further, according to this embodiment, the brake B2 and the brake B1 are, B2 accumulator A _B2 and B1 accumulator A ₁ line pressure is acting as a back pressure are respectively connected, in the non-engine braking range in 1 → 2 shift period in order to achieve the second gear, since the shift transient hydraulic pressure control unit 0.99 (SA4) is to lower than the line pressure P _L to the engine braking range, the As compared with a case where the engagement pressure P _B2 of the brake _B2 and the engagement pressure P _{B1 of the} brake B1 are directly controlled, there is an advantage that the control is simplified and the reliability is increased.
[0038]
As described above, one embodiment of the present invention has been described with reference to the drawings. However, the present invention can be applied to other aspects.
[0039]
For example, although in the foregoing embodiments, the engagement pressure _{P B1} of the engagement pressure _{P B2} and the brake B1 of the brake B2, using the line pressure _{P L} exerted as back pressure to the B2 accumulator _{A B2} and B1 accumulator _{A 1} Although the control is performed, the engagement pressure P _B2 of the brake _B2 and the engagement pressure P _{B1 of the} brake B1 may be directly controlled by a linear solenoid valve provided individually.
[0040]
Further, in the above-described embodiment, the 1 → 2 shift has been described, but another shift may be performed according to the configuration of the automatic transmission 14. In short, it suffices that the number of hydraulic friction engagement devices for achieving the predetermined gear is increased in the L range and in the L range as compared with the D range.
[0041]
Further, the above-mentioned automatic transmission 14 may be configured to have five forward speeds, and the engine brake range in which the shift lever 88 is operated is three ranges between two ranges and the D range. It may be provided.
[0042]
The above is merely an example of the present invention, and the present invention can be variously modified without departing from the gist thereof.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of a vehicle power transmission device including a control device according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a shift speed achieved by a combination of operations of a friction engagement device provided in the automatic transmission of FIG. 1;
FIG. 3 is a block diagram schematically illustrating a main configuration of a hydraulic control device that controls the automatic transmission of FIG. 1;
FIG. 4 is a hydraulic circuit diagram specifically illustrating a hydraulic circuit configuration of the source pressure generating device of FIG.
FIG. 5 is a functional block diagram for explaining a main part of a control function of the shift electronic control device of FIG. 1;
FIG. 6 is a time chart for explaining an operation of a shift transient control of the shift electronic control device of FIG. 1;
FIG. 7 is a diagram illustrating characteristics of the linear solenoid valve SLT of FIG. 4;
FIG. 8 is a diagram showing a relationship selected by the shift transient hydraulic control means of FIG. 5 according to whether a non-engine brake range or an engine brake range is used to determine a drive signal.
By shifting the transient hydraulic pressure control means [9] 5 is a diagram showing a line pressure P _L is switched in accordance with whether the engine braking range is unsubstituted or engine braking range.
10 is a flowchart illustrating a control operation of the shift electronic control device of FIG. 1, and is a diagram illustrating a 1 → 2 shift transient hydraulic control routine.
[Explanation of symbols]
14: Automatic transmission 146: Running range determining means 148: Shift determining means 150: Shift transient hydraulic control means B2 Brake: (first hydraulic friction engagement device)
B1 brake: (second hydraulic friction engagement device)

Claims (1)

In an automatic transmission for a vehicle in which a gear is selected by a combination of operations of a plurality of hydraulic friction engagement devices, in order to establish a predetermined gear, a first hydraulic friction engagement device is used in a non-engine brake range. A control device of a type for engaging and engaging a second hydraulic friction engagement device in addition to the first hydraulic friction engagement device in an engine brake range,
At the time of the upshift to the predetermined gear, under the same engine load or the same magnitude of the input torque of the automatic transmission , the shift transient hydraulic pressure of the first hydraulic friction engagement device in the engine brake range is set to the A control apparatus for an automatic transmission for a vehicle, comprising: a shift transient hydraulic pressure control unit that lowers the shift transient hydraulic pressure control as compared with a non-engine brake range.

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