JP2001330120A - Controller for continuously variable transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent slippage of a power transmission member of a continuously variable transmission in abrupt deceleration, or to make driving feeling kept favorably in addition thereto. SOLUTION: Since clamping-pressing force controlled by a clamping-pressing force control means 92 in response to a traveling condition of a vehicle is increased by a clamping-pressing force increasing means 104 when that variable speed for a belt type continuously variable transmission 18 is required to be increased is determined by a determination means 98 for determining whether the variable speed is required to be increased or not, the slippage of the transmission belt 48 is prevented favorably and the driving feeling is kept favorably while worsening of a fuel consumption and lowering of durability of the transmission belt 48 are prevented favorably, in the abrupt deceleration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a continuously variable transmission for a vehicle, and more particularly to a technique for optimally adjusting a clamping force of a power transmission member.

[0002]

2. Description of the Related Art In a continuously variable transmission for a vehicle that transmits power through friction between a power transmission member for transmitting power and a power transmission member, when a sensor for detecting the rotation speed of a prime mover is abnormal, the power transmission member is used. There has been proposed a control device for a continuously variable transmission for a vehicle of a type in which a squeezing pressure on the power transmission member is increased to a maximum value to prevent the power transmission member from slipping. For example,
This is the control device for a continuously variable transmission for a vehicle described in Japanese Patent Application Laid-Open No. 1-1245. According to this, when the vehicle is suddenly decelerated, the continuously variable transmission is suddenly decelerated, and the power transmission member is prevented from slipping by increasing the clamping pressure of the transmission belt by a constant value during that period. Has become.

[0003]

According to the conventional control apparatus for a continuously variable transmission for a vehicle, the amount of increase in the squeezing pressure of the power transmission belt during the rapid deceleration control period is a constant value that is set uniformly. Although slippage of the power transmission member is prevented, fuel pressure and durability of the power transmission member decrease due to unnecessarily large squeezing pressure in the running state, and the shift speed during downshifting of the continuously variable transmission. Was too high, and the driving feeling was sometimes impaired. For example, during rapid deceleration, if the rotational inertia energy on the engine side is excessively applied due to a sudden downshift, slippage of the power transmission member of the continuously variable transmission may occur, and if the input side rotational speed is excessively high. The shift feeling is impaired. Also, during the sudden acceleration request period, when the rotational inertia energy of the engine is excessively applied due to the sudden downshift, the power transmission member of the continuously variable transmission may slip, and the input side rotational speed may be reduced. Is excessive, and the shift feeling is impaired. Further, when the temperature of the hydraulic oil (lubricating oil) is low, the load on the input side (engine side) of the continuously variable transmission becomes large due to excessive friction due to an increase in the viscosity of the hydraulic oil, for example. In this case, there was a possibility that the power transmission member slipped.

The present invention has been made in view of the above circumstances, and a first object of the present invention is to prevent a power transmission member of a continuously variable transmission from slipping at the time of rapid deceleration shifting, or In addition, it is an object of the present invention to provide a control device for a continuously variable transmission for a vehicle in which a driving feeling is suitably maintained. It is a second object of the present invention to provide a control device for a continuously variable transmission for a vehicle in which the power transmission member does not slip even when the operating oil temperature is low.

[0005]

A first aspect of the present invention to achieve the above object is to transmit power through friction between a power transmission member for transmitting power. A continuously variable transmission for a vehicle, comprising: a control device for a continuously variable transmission for a vehicle, comprising a clamping force control means for controlling a clamping force to a power transmission member thereof in a necessary and sufficient manner. And (b) the shift speed increase request determining unit determines that the shift speed increase request of the continuously variable transmission is in progress. In such a case, a squeezing force increasing means for increasing a squeezing force controlled by the squeezing force control means according to a running state of the vehicle is included.

[0006]

In this way, when the shift speed increasing request determining unit determines that the shift speed increasing request of the continuously variable transmission is being performed, the clamping force increasing unit determines whether the vehicle speed is increasing. Since the squeezing pressure controlled by the squeezing pressure control means is increased in accordance with the running state, an appropriate squeezing pressure according to the running state can be obtained. , The slippage of the power transmission member is preferably prevented, and the driving feeling is suitably maintained during rapid deceleration shifting.

[0007]

A second aspect of the present invention to achieve the above object is that power is transmitted through friction between a power transmission member for transmitting power. A continuously variable transmission for a vehicle, comprising: a control device for a continuously variable transmission for a vehicle, comprising: a clamping force control unit configured to control a clamping force on a power transmission member of the vehicle continuously and in a necessary and sufficient manner;
(a) an oil temperature sensor for detecting the temperature of the operating oil of the continuously variable transmission; and (b) the clamping pressure control means when the operating oil temperature detected by the oil temperature sensor is lower than a predetermined value. And a squeezing force increasing means for increasing the squeezing force controlled by

[0008]

In this way, when the operating oil temperature detected by the oil temperature sensor is a low temperature equal to or lower than a predetermined value, the clamping pressure controlled by the clamping pressure control means is reduced by the clamping pressure increasing means. Increased. Therefore, the slippage of the power transmission member, which tends to occur due to an increase in the load on the input side when sudden deceleration running starts due to an increase in the friction on the input side due to the low oil temperature, is suitably prevented.

[0009]

Another aspect of the present invention is preferably that the first invention,
In the second invention, the continuously variable transmission includes a pair of input shafts and an output shaft that are parallel to each other, and a fixed rotating body fixed to the pair of input shafts and the output shaft, and a V between the fixed rotating body. A pair of variable pulleys, each having a variable effective diameter, comprising a pair of input shafts and a movable rotating body provided on the output shaft so as to be non-rotatable around the shafts and movable in the axial direction to form the grooves; And a pair of input-side hydraulic cylinders and output-side hydraulic cylinders that apply a thrust toward the solid rotating body to the movable rotating body. With this configuration, when the shift speed increase request determination unit determines that the shift speed increase request of the belt-type continuously variable transmission is being requested, the squeezing force increase unit determines the shift speed in response to the traveling state of the vehicle. Since the squeezing pressure controlled by the squeezing force control means is increased, slippage of the transmission belt is suitably prevented during a rapid deceleration shift, and the driving feeling is suitably maintained.

Preferably, in the first invention,
The shifting speed increase request determining unit determines whether or not the vehicle is in a manual shifting period. With this configuration, during the shift speed increase request period during the manual shift period, for example, during the period in which the manual shift mode is selected, the clamping force controlled by the clamping force control unit is increased according to the traveling state of the vehicle. Therefore, at the time of rapid deceleration shifting by manual shifting, slippage of the power transmission member is suitably prevented, and the shift is speeded up, and the driving feeling is suitably maintained.

[0011] Preferably, in the first invention,
The shifting speed increase requesting determining means determines whether or not a rapid acceleration period is in progress. With this configuration, the clamping force controlled by the clamping force control unit is increased according to the traveling state of the vehicle during the rapid acceleration operation,
At the time of a sudden deceleration shift at the time of a sudden acceleration operation, slippage of the power transmission member is suitably prevented, and the shift is promptly performed so that the driving feeling is suitably maintained.

Preferably, in the first invention,
When the shift speed increase request determining unit determines that the vehicle is in the manual shift period, the clamping force increasing unit determines the actual vehicle speed and the gear ratio of the continuously variable transmission from a relationship stored in advance. Is calculated based on the squeezing pressure, and the squeezing pressure increase value is added to the squeezing pressure controlled by the squeezing pressure control means. The above relationship is preferably
The squeezing pressure increase value is set such that the squeezing pressure increase value increases as the vehicle speed decreases, and the squeezing pressure increase value decreases as the vehicle speed ratio increases. With this configuration, the input-side rotation speed during the rapid deceleration shift is set to an appropriate value according to the vehicle speed and the speed ratio, so that an appropriate high shift speed is obtained, and slippage of the power transmission member is prevented. The driving feeling is suitably maintained.

Preferably, in the first invention,
When the shift speed increase request determining unit determines that the period is a rapid acceleration period, the clamping force increasing unit calculates a clamping pressure increase value based on an actual accelerator operation speed from a relationship stored in advance. And a squeezing force controlled by the squeezing force control means and an increased value of the squeezing force.
The above relationship is preferably set such that the higher the accelerator operation speed, the greater the value of the clamping pressure increase. With this configuration, the clamping force controlled by the clamping force control means is increased in accordance with the accelerator operation speed of the vehicle during the rapid acceleration operation, and therefore, during the sudden deceleration (sudden downshift) during the rapid acceleration operation. In addition, the transmission speed is set to an appropriate high speed corresponding to the accelerator operation speed, so that the slip of the power transmission member is suitably prevented, and the driving feeling is suitably maintained.

More preferably, the above relationship is such that as the accelerator operation speed increases, the clamping pressure increase value increases, as the vehicle speed decreases, the clamping pressure increase value increases, and as the transmission ratio increases, the clamping pressure increase value decreases. The squeezing force increasing means calculates an squeezing pressure increase value based on the actual accelerator operation speed, vehicle speed, and gear ratio from the above relationship, and is controlled by the squeezing force control means. The increase in the squeezing pressure is added to the squeezing pressure. With this configuration, the squeezing force controlled by the squeezing force control means is increased according to the accelerator operation speed, the vehicle speed, and the gear ratio, so that the accelerator operation speed, the vehicle speed, and An appropriate high shift speed is set according to the speed ratio, slippage of the power transmission member is suitably prevented, and the driving feeling is suitably maintained.

[0015]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a skeleton view of a power transmission device 10 including a vehicle belt-type continuously variable transmission 18 to which a control device according to one embodiment of the present invention is applied. The power transmission device 10 is suitably employed, for example, in a laterally mounted FF (front engine / front drive) driven vehicle, and includes an engine 12 which is an internal combustion engine used as a power source for traveling. The output of the engine 12 is supplied from a torque converter 14 to a forward / reverse switching device 16 and a belt-type continuously variable transmission (C).
VT) 18, and transmitted to the differential gear device 22 via the reduction gear 20, and distributed to the left and right drive wheels 24 </ b> L and 24 </ b> R. The belt-type continuously variable transmission 18 is provided with left and right driving wheels (for example, front wheels) 24L,
It is provided in a power transmission path leading to 4R.

The torque converter 14 is used for the engine 1
The pump impeller 14p connected to the second crankshaft, the turbine impeller 14t connected to the forward / reverse switching device 16 via the turbine shaft 34, and a non-rotating member rotatably supported via a one-way clutch. And a fixed-wing wheel 14s for transmitting power via fluid. A lock-up clutch (direct coupling clutch) 26 for integrally connecting the pump impeller 14p and the turbine impeller 14t so as to be able to rotate integrally with each other is provided between the pump impeller 14p and the turbine impeller 14t. Is provided.

The forward / reverse switching device 16 is constituted by a double pinion type planetary gear device. The turbine shaft 34 of the torque converter 14 is connected to the sun gear 16 s, and the input shaft 36 of the belt type continuously variable transmission 18. Is carrier 1
6c. Then, when the shift lever 67 is operated to the forward traveling range such as the D, 2, or L range, the hydraulic forward clutch 38 disposed between the carrier 16c and the sun gear 16s is engaged. The forward / reverse switching device 16 is integrally rotated so that the turbine shaft 34 is directly connected to the input shaft 36, and the driving force in the forward direction is transmitted to the drive wheels 24R and 24L. When the shift lever 67 is operated to the reverse travel range, which is the R range, the hydraulic reverse brake 40 disposed between the ring gear 16r and the housing is engaged, and the forward clutch 38 is released. Then, the input shaft 36 is rotated in the reverse direction with respect to the turbine shaft 34, and the driving force in the reverse direction is transmitted to the drive wheels 24R and 24L.

The belt-type continuously variable transmission 18 includes an input-side variable pulley 4 provided on the input shaft 36 and having a variable effective diameter.
2, an output variable pulley 46 provided on the output shaft 44 and having a variable effective diameter, and a transmission belt 48 wound around the V groove of the variable pulleys 42 and 46. Transmission belt 48 and variable pulley 4 functioning as
Power transmission is performed via frictional force between the inner wall surfaces of the V-grooves 2 and 46. Variable pulleys 42, 46
Is provided with an input-side hydraulic cylinder 42c and an output-side hydraulic cylinder 46c for changing the width of each V-groove, that is, the hanging diameter of the transmission belt 48, and is supplied to or from the hydraulic cylinder 42c of the input-side variable pulley 42. As the flow rate of the discharged hydraulic oil is controlled by the shift control valve device 50 (see FIG. 3) in the hydraulic control circuit 52, the V-groove width of both the variable pulleys 42 and 46 changes, and the transmission belt 48 is engaged. The diameter (effective diameter) is changed, and the speed ratio γ (= input-side rotation speed N _IN / output-side rotation speed N _OUT ) is continuously changed.

The hydraulic pressure P _B in the hydraulic cylinder 46c of the output-side variable pulley 46 corresponds to the squeezing pressure of the variable pulley 46 on the transmission belt 48 and the tension of the transmission belt 48, respectively. Since it is closely related to the tension, that is, the pressing force of the transmission belt 48 against the inner wall surfaces of the V-grooves of both the variable pulleys 42 and 46, it can also be called a belt tension control pressure, a belt clamping pressure control pressure, and a belt pressing force control pressure. In order to prevent the transmission belt 48 from slipping, the clamping pressure control valve 60 in the hydraulic control circuit 52 is
The pressure is regulated.

FIGS. 2 and 3 show an example of the hydraulic control circuit 52. FIG. 2 shows a circuit related to the pressure adjusting operation of the belt tension control pressure, and FIG. 3 shows a circuit related to the speed ratio control. Each is shown. In FIG. 2, the oil tank 5
Hydraulic oil refluxed 6 is pumped by a hydraulic pump 54 driven by the engine 12, after the pressure is regulated to a line pressure P _L by a not-shown line pressure regulating valve, a linear solenoid valve 58 and clamping pressure control valve 60 Supplied as source pressure. The linear solenoid valve 58 includes an electronic control device 66
By controlling the exciting current from (see FIG. 4),
From the hydraulic pressure of the hydraulic oil supplied from the hydraulic pump 54 is supplied to the clamping pressure control valve 60 by generating a control pressure P _S of a size corresponding to the exciting current. Clamping pressure control valve 60, the control pressure P _S to generate a hydraulic pressure P _B that is raised in accordance with increases, by feeding the hydraulic cylinder 46c of the output side variable pulley 46, to the extent that the transmission belt 48 does not slip The pinching pressure on the transmission belt 48, that is, the tension of the transmission belt 48 is reduced as much as possible. Its oil pressure P _B increases the frictional force between the accompanied in its raised and the belt clamping pressure or variable pulleys 42, 46 and the transmission belt 48.

[0022] The linear solenoid valve 58, while the oil chamber 58a of the control pressure P _S which is output therefrom at ON cutback valve 62 is supplied is provided, the cut-back valve 62 OFF times, to the oil chamber 58a are adapted to control pressure P _S supply is cut off by the oil chamber 58a of are opened to the atmosphere of, so that the time on the cut-back valve 62 characteristic of the control pressure P _S than when off is switched to the low-pressure side It has become. When the lock-up clutch 26 of the torque converter 14 is turned on (engaged), the cutback valve 62 is turned on by supplying a signal pressure P _ON from a solenoid valve (not shown).

In FIG. 3, the transmission control valve device 50
Is an upshift control valve 50 _U that exclusively supplies the hydraulic oil of the line pressure P _L to the hydraulic cylinder 42 c of the input-side variable pulley 42 and controls the upshift speed by controlling the hydraulic oil flow rate; and The hydraulic cylinder 42
The downshift control valve 50D controls the downshift speed by controlling the flow rate of the hydraulic oil discharged from the control valve _50D.
It is composed of This up-shift control valve 50 _U
A spool valve 50 _Uv that opens and closes between a line oil passage _L that guides the line pressure P _L and the input side hydraulic cylinder 42 c, and a spring 50 that urges the spool valve 50 _Uv in the valve closing direction.
_Us and a control oil chamber 50 _Uc for guiding the control pressure output from the up-side solenoid valve 64 _U. Further, downshift control valve 50 _D is input hydraulic cylinder and drain oil passage D 42
a spool valve element 50 _Dv that opens and closes between is c, a spring 50 for biasing the spool valve element 50 _Dv in the closing direction
And _ds, and a control hydraulic chamber 50 _Dc for guiding a control pressure that is output from the down side the solenoid valve 64 _D. The up-side electromagnetic valve 64 _U and the down-side electromagnetic valve 64 _D, the electronic control unit 6
The control pressure continuously changed by the duty drive by the control unit 6 is supplied to the control oil chamber 50 _Uc and the control oil chamber 50 _Dc, and the speed ratio γ of the belt-type continuously variable transmission 18 is continuously increased to the up side and the down side. Change. Note that the shift-down control valve 50 _D, the line oil passage L and the input-side hydraulic cylinder 42c in the closed position of the spool valve element 50 _Dv
And a flow passage 61 having a small flow cross-sectional area is formed between the transmission gear 61 and the speed change ratio γ when the upshift control valve _50U and the downshift control valve _50D are both closed. In order to prevent this, restrict from line oil passage L
3. The working oil is slightly supplied through the one-way valve 65 and the flow passage 61.

The electronic control unit 66 shown in FIG. 4 includes a signal indicating the operation position P _SH from an operation position detection sensor 68 for detecting the operation position of the shift lever 67, and a mode changeover switch 84.
, A signal indicating a manual shift operation from an upshift switch 88 _U and a downshift switch 88 _D, and an opening θ _ACC of an accelerator pedal 71 for changing an opening of a throttle valve 70. signal representing the accelerator opening theta _ACC from the accelerator operation amount sensor 72, a signal indicative of the rotational speed N _E of the engine rotational speed sensor 73 for detecting the rotational speed N _E of the engine 12, the vehicle speed V (specifically, output A signal representing the vehicle speed V from a vehicle speed sensor (output-side rotational speed sensor) 74 for detecting the rotational speed N _OUT of the shaft 44, and a signal from an input-side rotational speed sensor 76 for detecting the input shaft rotational speed N _IN of the input shaft 36. A signal representing the input shaft rotation speed N _IN , a hydraulic oil temperature T from an oil temperature sensor 78 that detects a hydraulic oil temperature T _OIL in the power transmission device 10, that is, the belt-type continuously variable transmission 18. A pressure sensor 80 for detecting a signal representative of the _OIL, the internal pressure P _B i.e. actual belt clamping pressure control pressure P _B of the hydraulic cylinder 46c of the output side variable pulley 46
, And a signal representing the oil pressure P _B is supplied.

FIG. 5 is a perspective view showing the console 82 of the vehicle, and FIG. 6 is a side view showing the steering wheel 86 of the vehicle. In FIG. 5, the shift lever 67 is provided upright on the upper surface of the console 82, and a mode changeover switch 84 is provided. The shift lever 67 has a P range position, an R range position, an N range position, It is designed to be selectively operated to a D range position, a 4 range position, a 3 range position, and a 2 range position. The mode changeover switch 84 is a seesaw type switch, and the shift lever 67 operates when the forward travel range (D,
The operation is performed to switch from the automatic transmission mode to the manual transmission mode or vice versa when the operation is performed in any of (4), (3) and (2). In FIG. 6, a pair of an automatic return type downshift switch 88 _D and an upshift switch 88 are provided on the left and right sides of the steering wheel 86.
_U is provided. When the manual shift mode is selected by the mode changeover switch 84, the upper limit value of the target input shaft rotational speed N _IN ^T of the belt-type continuously variable transmission 18 by the shift-down switch 88 _D is operated by a predetermined value is raised, the belt-type continuously variable transmission by the shift-up switch 88 _U is operated 1
Upper limit of the target input shaft rotational speed N _IN ^T 8 is adapted to be decreased by a predetermined value.

The electronic control unit 66 includes a CPU, an RO,
M, a RAM, a so-called microcomputer including an input / output interface, and the like.
By performing signal processing in accordance with a program stored in the ROM in advance while utilizing the temporary storage function, the shift control and the clamping pressure control of the continuously variable transmission 18 are performed.
Specifically, in the shift control, for example, an accelerator operation amount, that is, an accelerator opening degree θ representing an actual required output amount of the driver from a relationship (map) stored in advance shown in FIG.
Calculates a target rotational speed N _IN ^T based on _{AC C} (%) and the vehicle speed V (corresponding to the output rotational speed N _OUT), the actual input rotational speed N _IN coincides with the target rotational speed N _IN ^T By operating the transmission control valve device 50 as described above, the flow rate of the hydraulic oil supplied into the hydraulic cylinder 42c of the input-side variable pulley 42 or the hydraulic oil discharged from the hydraulic cylinder 42c is controlled. FIG. 7 shows, for example, a relationship previously determined for operating the engine 12 along an optimal curve in which the output and the fuel consumption are optimal, wherein γ _max is the maximum gear ratio, and γ _min is the minimum gear ratio. Ratio.

In the belt squeezing pressure control, the electronic control unit 66 uses a predetermined relationship (map) to obtain a necessary and sufficient necessary oil pressure (a target oil pressure corresponding to an ideal belt squeezing pressure). A belt clamping pressure control pressure (target value) is calculated based on the accelerator operation amount θ _ACC corresponding to the actual input torque T _IN or the transmission torque of the belt type continuously variable transmission 18 and the actual gear ratio γ, and the belt clamping is performed. The squeezing pressure control valve 60 in the hydraulic control circuit 52 is adjusted to obtain a pressure control pressure.

FIG. 8 is a functional block diagram for explaining a main part of the control function of the electronic control unit 66, that is, a belt clamping pressure control and the like. In FIG. 8, the shift control means 90
During the operation of the vehicle, the actual accelerator opening θ _{ACC is obtained} from a relationship (map) stored in advance shown in FIG. 7, for example.
(%) And calculates the target rotational speed N _IN ^T based on the vehicle speed V (corresponding to the output rotational speed N _OUT), so that the actual input rotational speed N _IN coincides with the target rotational speed N _IN ^T determining the shift control valve device 50 of the up-shift control valve 50 _U or down shift control valve 50 _D of the drive duty ratio D (%), by executing a feedback controlled to operate in its drive duty ratio D, the input side variable Pulley 42
Of the hydraulic oil supplied to the hydraulic cylinder 42c of the hydraulic cylinder 42c or the hydraulic oil discharged from the hydraulic cylinder 42c of the input-side variable pulley 42.

The squeezing pressure control means 92 is provided with a necessary and sufficient hydraulic pressure (corresponding to an ideal belt squeezing pressure) to obtain a squeezing pressure on the transmission belt 48 as small as possible without causing slippage of the transmission belt 48. From the predetermined relationship (map) to obtain the actual input torque T _IN or the accelerator operation amount θ _ACC and the actual gear ratio γ corresponding to the transmission torque of the belt type continuously variable transmission 18 in order to obtain the target hydraulic pressure. Te belt clamping pressure control pressure (target value) is calculated P _B ^T, the actual belt clamping pressure control pressure P _B is the target value P _B ^T
The pressure is controlled by the squeezing pressure control valve 60 in the hydraulic control circuit 52 so as to perform the feedback control that matches the pressure.

The vehicle speed calculating means 94 is provided by a vehicle speed sensor 74.
The rotation speed N of the output shaft 44 detected_OUTAnd drive wheels
The vehicle speed V is calculated based on the diameters of 24L and 24R. Strange
The speed ratio calculating means 96 is provided by an input-side rotational speed sensor 76.
Detected input shaft rotation speed N _INAnd the vehicle speed sensor 74
Output shaft rotation speed N_OUTFrom belt type stepless
The actual gear ratio γ of the transmission 18 (= N_IN/ N_OUT)
I do.

The shifting speed increasing request determining means 98 determines whether a downshift that occurs when the shift lever 67 is operated from the D range to the engine brake range (4, 3, 2 range), or a manual shifting mode, for example. and the manual downshift operation by the down-shift switch 88 _D when being selected, such as during rapid acceleration operation the accelerator pedal 71 is depressed rapidly, the input shaft rotational speed N _iN (engine quickly during downshifting It is determined whether a shift speed increase request of the belt-type continuously variable transmission 18 that needs to increase the speed N _E ) is being issued. When the manual shift mode is selected by the mode changeover switch 84, a crisp and sporty running property is required. Therefore, in order to realize a quick manual shift, an increase in the shift speed is required more than in the automatic shift mode. The shifting speed increase request determination unit 98
Manual shifting mode determining means determines that the mode changeover switch 84 manual shift mode is the manual shifting mode to manual shifting operation is performed by the selected and the down-shift switch 88 _D or upshift switch 88 _U 100
When the manual shift determination unit 100 determines that a manual shift is being performed, it is determined that a shift speed increase request is being issued. When the accelerator pedal 71 is rapidly depressed, a sudden increase in the driving force due to a downshift is required.
8 is a request for rapid acceleration based on the fact that the change rate (change speed) Δθ _{ACC of} the accelerator opening θ _ACC detected by the accelerator operation amount sensor 72 exceeds a predetermined reference value A (° / sec). And a sudden acceleration request determining means 102 for determining that the vehicle is in the middle of the vehicle.
When it is determined that a rapid acceleration request is being made, it is determined that a shift speed increase request is being made during the acceleration period. The criterion value A (° / sec) is used to reduce the clamping pressure of the power transmission belt 48 in order to obtain an optimum speed while preventing slippage of the power transmission belt 48 during a rapid deceleration speed associated with the rapid depression of the accelerator pedal 71. The purpose is to determine whether or not it is necessary to increase the speed quickly.

The squeezing pressure increasing means 104 is provided for increasing the shifting speed.
The shift speed increasing request is being made by the adding request determining means 98.
Is determined according to the running state of the vehicle.
The clamping pressure controlled by the pressure control means 92 is increased.
You. For example, it is controlled by the clamping force control means 92.
A predetermined clamping pressure increase value P_UPBy adding
Thus, the clamping pressure of the transmission belt 48 is increased. Above clamping pressure
In the increasing means 104, the manual shift determining means 10 is used.
0, it is determined that manual shifting is in progress.
Optimum clamping force is obtained during shifting by shifting operation
From relations (functions or maps) stored in advance
Vehicle speed V and the speed ratio γ of the belt-type continuously variable transmission 18 at the time of
Squeezing pressure increase value P based on_UPIs calculated. This clamping pressure increase
Added value P_UPBetween the vehicle speed V and the speed ratio γ
Slip of the power transmission belt 48 during sudden deceleration during shifting
The optimal shifting speed to prevent the shift feeling while preventing
This is for the purpose of
FIG. 10 shows the change tendency of each parameter.
Thus, as the vehicle speed V decreases, the clamping pressure increase value P_UPIncreases
And as the speed ratio γ increases, the clamping pressure increase value P_UPBut
It is obtained experimentally in advance so as to decrease. Ma
In addition, the pinching pressure increasing means 104 is
It is determined by the determination means 102 that a rapid acceleration request is being made.
In order to obtain the optimum clamping pressure when sudden acceleration is required,
From the stored relationship (function or map)
Cell opening θ_ACCChange rate (operation speed of the accelerator pedal 71)
Degree) Δθ_ACC, Vehicle speed V, and belt type continuously variable transmission 18
Pressure increase value P based on the gear ratio γ of _UPIs calculated.
This clamping pressure increase value P_UPAnd vehicle speed V, gear ratio γ, and change
Rate Δθ _ACCRelationship with sudden deceleration when sudden acceleration is requested
Prevents the transmission belt 48 from slipping at high speed and reduces the feeling of shifting.
In order to obtain the optimal shift speed for avoiding
For example, FIGS. 9, 10 and 11 show
As shown in FIG.
Indeed, the clamping pressure increase value P_UPIncreases, and the gear ratio γ increases.
Indeed, the clamping pressure increase value P_UPDecreases and the rate of change Δθ
_ACCIncreases, the clamping pressure increase value P_UPIncreases
Are determined experimentally in advance. More specifically,
9 shows that the clamping pressure increases as the vehicle speed V decreases.
The lower the vehicle speed, the faster acceleration is required.
Increase the downshift speed and increase the shift speed by increasing
Transmission caused by generation of inertia torque due to increase
It is set to prevent the belt 48 from slipping.
Also, the pinching pressure decreases as the gear ratio γ in FIG. 10 increases.
The relationship is that the transmission belt 48
Unnecessary to prevent slippage due to large contact area
Fuel consumption and the transmission belt 48
If the durability decreases or the downshift speed becomes larger than necessary
And set to prevent. Accelerator of Fig. 11
Pedal operation speed Δθ_ACCIncreases with increasing clamping pressure
As shown in FIG. 9, the higher the operating speed, the more rapid acceleration is required.
It is set up to address what is required.

Further, the clamping pressure increasing means 104 corrects the belt clamping pressure control pressure P _B that is controlled by the clamping pressure control unit 92 based on the hydraulic oil temperature T _OIL detected by the oil temperature sensor 78. For example, a belt-type continuously variable transmission 1
In FIG. 8, the friction due to the viscosity of the hydraulic oil, which increases as the temperature decreases, increases, and the rotational resistance of the engine 12 and the forward / reverse switching device 16 increases during deceleration, causing the transmission belt 4 to rotate.
In order to prevent the occurrence of the slip of No. 8 as the hydraulic oil temperature T _OIL decreases, the increase value P _{UP of the} belt clamping pressure control pressure P _B increases with the increase value P _UP determined from the relationship that the belt clamping force increases. It is added to the pressure control pressure P _B.

FIG. 12 is a flow chart for explaining a main part of the control operation of the electronic control unit 66, which shows a clamping pressure increasing control routine for increasing the shift speed, which is repeatedly executed at a predetermined cycle time. is there. In FIG. 12, first, in a step SA1 corresponding to the manual shift determining means 100 (hereinafter, the step is omitted) SA1, for example, during a downshift when the shift lever 67 is operated from the D range to the engine brake range, or during mode switching. whether a manual downshift in the manual downshift operation is performed by the down-shift switch 88 _D in a state where the manual shift mode is selected by the switch 84 is determined. If the determination at SA1 is affirmative, the control returns to SA2.
After the clamping pressure increase value P _UP is determined based on the actual vehicle speed V and the speed ratio γ from the relationship stored in advance,
In SA3, the squeezing pressure increase value P _UP determined in SA2 is added to the belt squeezing pressure control pressure P _B controlled by the squeezing force control means 92, so that the transmission belt 48 is increased.
Is increased.

If the determination in SA1 is denied, the change rate Δθ _ACC of the accelerator opening θ _ACC detected by the accelerator operation amount sensor 72, ie, the accelerator operation, is performed in SA4 corresponding to the sudden acceleration request determination means 102. Judgment reference value A (° / sec) where speed Δθ _ACC is set in advance
Is determined. If the determination in SA4 is denied, this routine is terminated. If the determination is affirmative, in SA5, the actual vehicle speed V, the gear ratio γ, and the accelerator operation speed Δθ are determined from the relationship stored in advance.
_The clamping pressure increase value P _UP is determined based on _ACC . Then, in SA3, the clamping pressure of the transmission belt 48 is increased by adding the clamping pressure increase value P _UP determined in SA5 to the belt clamping pressure control pressure P _B controlled by the clamping force control means 92. . In this embodiment, the above S
A2, SA3 and SA5 correspond to the clamping force increasing means 104.

As described above, according to the present embodiment, when the shift speed increase request determination means 98 (SA1, SA4) determines that the shift speed increase request of the belt type continuously variable transmission 18 is being requested. Is the clamping force increasing means 104 (SA2, S
A3, SA5), the squeezing force controlled by the squeezing force control means 92 is increased in accordance with the running state of the vehicle, so that the fuel consumption and the durability of the transmission belt 48 are prevented from being reduced during rapid deceleration shifting. In addition, slippage of the transmission belt 48 is suitably prevented, and a quick shift speed is obtained, so that the driving feeling is suitably maintained.

Further, according to the present embodiment, the shifting speed increasing request determining means 98 includes the manual shifting determining means 100 for determining whether or not the vehicle is in the manual shifting period. When the determination means 100 determines that the vehicle is in the manual gear shift period, it determines that a shift speed increase request is in progress. In this way, during the shift speed increase request period during the manual shift period, for example, during the period in which the manual shift mode is selected, the clamping force controlled by the clamping force control means 92 according to the running state of the vehicle is increased. Therefore, at the time of rapid deceleration shifting by manual shifting, slippage of the transmission belt 48 is suitably prevented, and the driving feeling is suitably maintained by the quick shifting speed.

Further, according to the present embodiment, the shifting speed increasing request determining means 98 includes the rapid acceleration request determining means 102 for determining whether or not the vehicle is in the period of requesting rapid acceleration.
If it is determined by the sudden acceleration request determination means 102 that the period is during the request for rapid acceleration of the vehicle, it is determined that the shift speed increase request is being performed. By doing so, the clamping force controlled by the clamping force control means 92 is increased according to the traveling state of the vehicle during the rapid acceleration operation,
At the time of a sudden deceleration shift during a sudden acceleration operation, slippage of the power transmission member is suitably prevented, and the driving feeling is suitably maintained by a quick shift speed.

Further, according to this embodiment, it is necessary to increase the shift speed.
It is determined that the vehicle is in the manual shift period by the requesting determination means 98.
If it is determined, the clamping force increasing means 104
Actual vehicle speed V and belt type continuously variable
The clamping pressure increase value P based on the speed ratio γ of the transmission 18_UPIs calculated
And the clamping force P controlled by the clamping force control means 92. _B
The increase value of the pinching pressure P_UPBecause it adds
Input side rotation speed N during rapid deceleration shifting_INIs the vehicle speed V and
Value appropriate for the gear ratio γ of the belt-type continuously variable transmission 18
The transmission bell is
To prevent slippage of the drive 48 and driving feeling
Is suitably maintained.

Further, according to the present embodiment, when the shift speed increasing request determining means 98 determines that the acceleration period is the rapid acceleration period, the clamping pressure increasing means 104 determines the actual accelerator position from the relationship stored in advance. Since the squeezing pressure increase value P _UP is calculated based on the operation speed Δθ _ACC and the squeezing pressure increase value P _UP is added to the squeezing pressure P _B controlled by the squeezing force control means 92, the rapid acceleration operation is performed. At this time, the squeezing force controlled by the squeezing force control means 92 is increased in accordance with the accelerator operation speed Δθ _ACC of the vehicle. And appropriate high shifting speed,
While the slip of the transmission belt 48 is suitably prevented,
The driving feeling is suitably maintained.

Further, according to the present embodiment, the relationship used by the clamping force increasing means 104 during the rapid acceleration request is such that as the accelerator operation speed Δθ _ACC increases, the clamping pressure increasing value P _UP increases and the vehicle speed V decreases. The clamping pressure increase value P _UP increases as the gear ratio decreases, and the clamping pressure increase value P _UP decreases as the gear ratio γ increases. A squeeze pressure increase value P _UP is calculated based on the accelerator operation speed Δθ _ACC , the vehicle speed V, and the gear ratio γ, and the squeeze pressure increase value P _UP is added to the squeeze pressure controlled by the squeeze force control means 92. since, the accelerator operating speed [Delta] [theta] _ACC at the time of rapid deceleration speed by rapid acceleration operation, is the vehicle speed V, and the gear ratio appropriate higher depending on the γ shift speed, slip of the power transmission member is prevented appropriately, luck Feeling can be suitably maintained.

Further, according to the present embodiment, the oil temperature sensor 78
When the hydraulic oil temperature T _OIL detected by the above is a low temperature equal to or lower than a predetermined value, the clamping pressure controlled by the clamping pressure control means 92 is increased by the clamping pressure increasing means 104, so that the input caused by the low oil temperature is increased. Due to the increase in the side friction, slippage of the transmission belt 48, which is likely to occur due to an increase in the load on the input side, when sudden deceleration starts, is suitably prevented.

Next, another embodiment of the present invention will be described. In the following description, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 13 shows a nip pressure increasing control routine for preventing the transmission belt from slipping at the time of rapid shifting.
In FIG. 13, the above-described shifting speed increase request determination means 9
In SB1 corresponding to 8 or the like, it is determined whether or not the rapid shift control is being performed. If the determination in SB1 is denied, this routine is terminated. If the determination is affirmative, in SB2 corresponding to the squeezing force increasing means 104, the squeezing pressure controlled by the squeezing force control means 92 is increased. . In this SB2, for example, the clamping force control means 92
The belt clamping force control pressure (target value) P _B ^T by increasing by increasing value P _UP within a period during the rapid change-speed control performed, as shown in the middle in the time chart of FIG. 14 in suddenly shift control performed The squeezing pressure of the transmission belt 48 is temporarily increased only in the middle period t _{1 to} t ₂ . The lower part of FIG. 14 shows the belt clamping pressure control pressure (target value) P _B ^T as described above.
Is not increased.

[0045] According to this embodiment, even pressure drop due to the hydraulic oil is consumed in large quantities in the abrupt speed change control period occurs, the target as described above value P _B ^T is increased value P _UP since is increased by, since in its abrupt speed change control period the belt squeezing force control pressure P _B obtained analogously to ordinary shift control period, slippage of the transmission belt 48 due to the pressure drop can be suitably prevented. As the increase value P _UP , for example, a value corresponding to the pressure drop of the belt clamping pressure control pressure P _B during the rapid shift control period is set.

Although the embodiment of the present invention has been described with reference to the drawings, the present invention can be applied to other embodiments.

For example, in the above embodiment, a pair of variable pulleys 42, 4 around which a transmission belt 48 is wound
Although the so-called belt-type continuously variable transmission 18 having the gear 6 is used, the present invention can be applied to other continuously variable transmissions such as a toroidal-type continuously variable transmission. In short, the gear ratio is stepless by changing the contact position of the power transmission member, which is interposed and pressed between the input side rotating body and the output side rotating body, with the input side rotating body and the output side rotating body. What is necessary is just a continuously variable transmission that can be changed to.

Further, in the above-described embodiment, the clamping pressure is increased.
In the means 104, the clamping pressure increase value P _UPTo ask for
The vehicle speed is a parameter that indicates the running state of the vehicle.
V and the gear ratio γ of the belt type continuously variable transmission 18 are used.
However, other parameters may be substituted. for example
If the output shaft rotation speed N_OUTAnd input shaft rotation speed N_INSpeed change
The value multiplied by the ratio γ may be used instead of the vehicle speed V,
For changing the groove width of the variable pulley 42 or 46 to the gear ratio γ
May be.

Although the embodiment of the present invention has been described in detail with reference to the drawings, this is merely an embodiment,
The present invention can be implemented in various modified and improved aspects based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram of a vehicle drive device to which a control device according to an embodiment of the present invention is applied.

FIG. 2 is a diagram showing a main part of a hydraulic control circuit for controlling a belt-type continuously variable transmission in the vehicle power transmission device shown in FIG. 1, showing a portion related to belt tension control.

FIG. 3 is a diagram illustrating a main part of a hydraulic control circuit for controlling a belt-type continuously variable transmission in the vehicle power transmission device in FIG. 1, illustrating a portion related to speed ratio control.

FIG. 4 is a diagram simply illustrating an electrical configuration of the control device of FIG. 1;

FIG. 5 is a perspective view showing a console portion provided in the cabin of the vehicle shown in FIG. 1;

FIG. 6 is a side view showing an upshift switch and a downshift switch provided on a steering wheel of the vehicle of FIG. 1 for performing a manual shift.

FIG. 7 is a diagram showing a relationship stored in advance that is used to determine a target rotation speed in a gear ratio control executed by the electronic control device of FIG. 4;

FIG. 8 is a functional block diagram illustrating a main part of a control function of the electronic control device of FIG. 4;

9 is a diagram for explaining a change tendency between a clamping pressure increase value and a vehicle speed in a relationship used for calculating a clamping pressure increase value by a clamping pressure increasing means in FIG. 8;

FIG. 10 is a diagram for explaining a change tendency between a clamping pressure increase value and a gear ratio in a relationship used for calculating a clamping pressure increase value by a clamping force increasing unit in FIG. 8;

11 is a diagram illustrating a change tendency between the clamping pressure increase value and the operation speed of the accelerator pedal in the relationship used for calculating the clamping pressure increase value by the clamping force increasing means in FIG. 8;

12 is a flowchart illustrating a main part of a control operation of the electronic control device in FIG. 8, and is a diagram illustrating a routine corresponding to a clamping pressure increase control unit and the like.

FIG. 13 is a flowchart illustrating a main part of a control operation of an electronic control unit according to another embodiment of the present invention.

FIG. 14 is a time chart for explaining the operation of the embodiment in FIG. 13;

[Explanation of symbols]

 18: Belt-type continuously variable transmission (continuously variable transmission) 48: Power transmission belt (power transmission member) 66: Electronic control unit 78: Oil temperature sensor 98: Shift speed increase request determination unit 100: Manual shift determination unit 102 : Sudden acceleration request determination means 104: Nipping pressure increasing means

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16H 59:44 F16H 59:44 59:72 59:72 (72) Inventor Daisuke Inoue Toyota-cho Toyota-cho, Aichi Prefecture 1 Toyota Motor Corporation (72) Katsumi Kono 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Koji Taniguchi 1 Toyota Town Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Hideki Yasue 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Ryoji Habuchi 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Koji Morioka Aichi (72) Inventor Hiroki Kondo 1 Toyota Town, Toyota City, Aichi Prefecture (72) Inventor Kenji Matsuo 1 Toyota Town, Toyota City, Aichi Prefecture F-term (reference) 3J552 MA07 MA09 MA12 MA17 MA26 NA01 NB01 PA12 PA59 PA63 PB03 RA07 RA12 RA23 RA24 RA27 RA29 RB16 RB19 SA32 SA36 SA53 SA54 SA57 SA59 TA01 TB06 VA18Y VA27Z VA32W VA32Y VA37Z VA48W VA62Z VA68Z VA70Z VA74W VA74Z VB01W VC01X VD02Z VD07W

Claims (5)

[Claims] 1. A continuously variable transmission for a vehicle that transmits power via friction between the power transmission member and a power transmission member for transmitting power, wherein a clamping pressure for controlling the clamping force on the power transmission member is necessary and sufficient. A control device for a continuously variable transmission for a vehicle, comprising: control means for controlling a continuously variable transmission for a vehicle, wherein a means for determining whether or not a request for increasing the speed of the continuously variable transmission is being performed is provided. A squeezing force increasing means for increasing a squeezing force controlled by the squeezing force control means in accordance with a traveling state of the vehicle, when it is judged by the judging means that a shift speed increase request of the continuously variable transmission is being issued; A control device for a continuously variable transmission for a vehicle, comprising: 2. The control device for a continuously variable transmission for a vehicle according to claim 1, wherein the shift speed increase request determination unit determines whether or not the vehicle is in a manual shift period. 3. The control device for a continuously variable transmission for a vehicle according to claim 1, wherein the shift speed increase request determination unit determines whether a rapid acceleration period is in progress. 4. The squeezing pressure increasing means calculates a squeezing pressure increase value based on a vehicle speed and a speed ratio of the continuously variable transmission.
2. The control device for a continuously variable transmission for a vehicle according to claim 1, wherein the increased value of the squeezing force is added to a squeezing force controlled by the squeezing force control means. 5. A continuously variable transmission for a vehicle that transmits power via friction between the power transmission member and a power transmission member for transmitting power, wherein a clamping pressure for controlling the clamping force on the power transmission member is necessary and sufficient. A control device for a continuously variable transmission for a vehicle, comprising a control unit, an oil temperature sensor for detecting a temperature of hydraulic oil of the continuously variable transmission, and a hydraulic oil temperature detected by the oil temperature sensor being a predetermined value. And a squeezing force increasing means for increasing the squeezing force controlled by the squeezing force control means when the temperature is low as described below.