JP3858314B2 - Control device for toroidal type continuously variable transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for a toroidal-type continuously variable transmission used in an automobile or the like.
[0002]
[Prior art]
Toroidal type continuously variable transmission, Sho 57-47060 publication, as is described in JP-58-54262 Publication and Japanese Patent 2-283949 discloses such a large power rollers between the input and output disks Force is transmitted by force, and power is transmitted by shearing of the oil film at the contact point between the input / output disk and the power roller.
The force acting at the time of power transmission is proportional to the vector of the difference between the velocity vectors of the disk and the power roller at the contact point.
[0003]
The speed change is performed by tilting the power roller to change the radius ratio of the input / output disk at the contact point. The power roller is supported by a roller support member so as to be rotatable and capable of tilting. The roller support member has a structure that can be displaced in the axial direction by a hydraulic cylinder device, and a lateral force is generated by this displacement to change speed.
[0004]
The hydraulic pressure of the hydraulic cylinder device is controlled by a shift control valve. This speed change control valve has a sleeve and a spool which are fitted in a state where they can move relative to each other. The position of one of the sleeve and the spool is controlled by an actuator such as a step motor in accordance with the target speed ratio obtained by the controller of the speed change control device, and the other is a cam (hereinafter referred to as a precess cam) in one of the roller support members. ), And the position is determined according to the tilt angle (transmission ratio) and the amount of displacement in the vertical direction by the effect of the slope of the recess cam.
[0005]
When the target speed ratio and the actual speed ratio fed back by the precess cam match, the relative positional relationship between the sleeve and the spool becomes the reference state, and the differential pressure of the hydraulic cylinder device, that is, the force acting in the axial direction of the roller support member is It will be in a state necessary to support the power for power transmission.
[0006]
On the other hand, when the target gear ratio is changed and the step motor is driven, or when the relative positional relationship between the sleeve and the spool deviates from the reference state due to the feedback of the recess cam due to some disturbance, the hydraulic pressure of the hydraulic cylinder device is The roller support member is configured to generate a force that displaces in the axial direction.
[0007]
[Problems to be solved by the invention]
However, in such a toroidal type continuously variable transmission, the conduit for supplying hydraulic oil from the transmission control valve to the hydraulic cylinder has a small diameter (about 1 cm or less) and a length of several tens of centimeters. Since it has a certain elongated shape, when the temperature is low and the viscosity of the hydraulic fluid is high, the pipe resistance increases, and it may not be possible to secure the hydraulic fluid flow rate to respond to the required shift control. There is a problem that there is.
[0008]
On the other hand, if the pipe diameter is increased, in the case of a general configuration in which a plurality of hydraulic cylinders are controlled by a single shift control valve, the mutual interference between the hydraulic cylinders becomes too strong.
[0009]
[Means for Solving the Problems]
In the present invention, in order to solve the above problems, means for heating the hydraulic oil is provided. Specifically, attention is paid to the fact that traction oil for transmitting torque is also used as hydraulic oil for lubrication between parts and gear shift control, and as hydraulic oil for torque converter.
[0010]
First, the temperature of the hydraulic oil is measured using an oil temperature detecting means such as a temperature sensor, and as a result, if it is determined that the oil temperature is lower than a predetermined reference value, it is determined where the shift position is. When it is in the parking range, the turbine runner cannot be rotated by controlling the clutch and brake of the forward / reverse switching device to directly connect the turbine runner and the torque transmission shaft of the continuously variable transmission mechanism. (When the shift position is parked, the output shaft of the continuously variable transmission mechanism is fixed because it is parked. Therefore, the torque transmission shaft is also fixed via the output disk, power roller, and input disk. The difference in rotational speed with the pump impeller is increased to convert most of the energy generated by the engine into heat energy in the torque converter. Be to conversion, it is to solve the above problems by causing soaring the hydraulic oil temperature.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on illustrated embodiments.
[0013]
1 and 2 show a toroidal-type continuously variable transmission according to the present invention, and FIG. 3 shows its cross section and the configuration of a transmission control system.
[0014]
In the toroidal continuously variable transmission 10 shown in FIG. 1, the rotation of an unillustrated engine as a power source provided on the left side in the drawing is input to the toroidal continuously variable transmission 10 via the torque converter 12. It has become.
[0015]
As is generally known, the torque converter 12 includes a pump impeller 12a, a turbine runner 12b, and a stator 12c. In particular, the torque converter 12 is provided with a lockup clutch 12d.
[0016]
The toroidal-type continuously variable transmission 10 is provided with a torque transmission shaft 16 disposed coaxially with the output rotation shaft 14 of the torque converter 12, and the torque transmission shaft 16 has a first toroidal transmission 18 and a first transmission. A two-toroidal transmission unit 20 is arranged in tandem.
[0017]
The torque transmission shaft 16 is hollow and is attached to the housing 22 so as to be slightly movable in the axial direction.
[0018]
The first and second toroidal transmissions 18, 20 have a pair of first input disk 18a, first output disk 18b, second input disk 20a, and second output disk 20b, each of which has a toroidal curved surface. And power rollers 18c, 18d, and 20c, 20d that are in frictional contact between the opposing surfaces.
[0019]
The first toroidal transmission unit 18 is disposed on the left side of the torque transmission shaft 16 in the drawing, and the second toroidal transmission unit 20 is disposed on the right side of the torque transmission shaft 16 in the drawing. The first input disk 18a and the second input disk 20a are arranged outside each other, and the first output disk 18b and the second output disk 20b are arranged inside each other.
[0020]
The first and second input disks 18a and 20a are attached to the torque transmission shaft 16 via ball splines 24 and 26 so as to be locked in the rotational direction and smoothly moved in the axial direction.
[0021]
On the other hand, the first and second output disks 18b and 20b are spline-fitted to an output gear 28 which is fitted to the torque transmission shaft 16 so as to be relatively rotatable, and are connected to the first and second output disks 18b and 20b. The transmitted rotational force is transmitted to the countershaft 30 through the output gear 28 and the input gear 30a meshed with the output gear 28, and further transmitted to an output shaft (not shown) through the rotational force output path.
[0022]
By the way, a loading cam device 34 is provided outside the first input disk 18a, and the engine rotation transmitted through the rotational force input path is input to the loading cam device 34, and according to the input torque. A pressing force is generated by the loading cam device 34.
[0023]
The loading cam 34 a of the loading cam device 34 is fitted to the torque transmission shaft 16 so as to be relatively rotatable, and is locked to the torque transmission shaft 16 via a thrust bearing 36. A disc spring 38 is provided between the second input disk 20a and the right end of the torque transmission shaft 16 in the drawing.
[0024]
Accordingly, the pressing force generated by the loading cam device 34 acts on the first input disk 18a and also acts on the second input disk 20a via the torque transmission shaft 16 and the disc spring 38, and The pre-pressure generated by the disc spring 38 acts on the second input disk 20a and also acts on the first input disk 18a via the torque transmission shaft 16 and the loading cam device 34. .
[0025]
By the way, a forward / reverse switching device 40 for switching the rotational direction during forward and reverse travel of the vehicle is provided in the rotational force input path between the loading cam device 34 and the torque converter 12.
[0026]
The forward / reverse switching device 40 includes a double planetary planetary gear mechanism 42, a forward clutch 44 capable of fastening the carrier 42a of the planetary gear mechanism 42 to the output rotating shaft 14, and a ring gear of the planetary gear mechanism 42. The reverse brake 46 can be fastened to the housing 22.
[0027]
In the forward / reverse switching device 40, the forward clutch 44 is engaged and the reverse brake 46 is released, so that the rotation in the same direction as the engine rotation is input to the loading cam device 34, and the forward clutch 44 is When the reverse brake 46 is engaged by releasing it, rotation in the reverse direction is input.
[0028]
In the planetary gear mechanism 42, 42c is a sun gear, and 42d and 42e are planetary gears engaged with each other.
[0029]
Incidentally, the power rollers 18c, 18d and 20c, 20d provided in the first toroidal transmission unit 18 and the second toroidal transmission unit 20 are arranged symmetrically with respect to the central axis c, and each power roller is a transmission control device. The first and second input disks 18a, 20a are rotated steplessly by being tilted (tilted) according to the vehicle operating conditions via the shift control valve 60 and the hydraulic actuators 50, 52, 54, 56. And is transmitted to the first and second output disks 18b and 20b.
[0030]
That is, the power rollers 18c, 18d and 20c, 20d are hydraulic actuators 50, 52, 54 provided corresponding to the power rollers 18c, 18d and 20c, 20d, respectively, as schematically shown in FIG. The trunnions 50a, 52a, 54a, 56a moved up and down by 56 are rotatably mounted via pivot shafts 50b, 52b, 54b, 56b, and the trunnions 50a, 52a, 54a, 56a are moved up and down. The power rollers 18c, 18d and 20c, 20d can be tilted.
[0031]
Accordingly, the amount of tilting of the power rollers 18c, 18d and 20c, 20d, that is, the amount of rotation of the trunnions 50a, 52a, 54a, 56a is determined by the operating amount of the hydraulic actuators 50, 52, 54, 56. become.
[0032]
When the select lever 95 (FIG. 2) is in the parking range, it is detected by the park switch 94, and the forward clutch 44 and the reverse brake 46 in the forward / reverse switching device 40 are both released, The parking pole 91 is engaged with the parking gear 90 via the rod 93 and the parking rod 92, and is parked.
[0033]
Here, the shift control of the present invention will be described with reference to FIG.
[0034]
The control valve 60 includes a rod 62 and a sleeve 63 that are driven by a step motor 61, a spool 64 that is fitted into the inner diameter portion of the sleeve 63, and a spring 65 that presses the spool 64 in a direction opposite to the step motor 61. ing.
[0035]
An axial groove is formed on the outer periphery of the sleeve 63, and a pin is engaged with the groove 63 so that the sleeve 63 can move in the axial direction without being rotated.
[0036]
Further, at the end of the spool 64 opposite to where the spring 65 is provided, the rotation amount and the axial movement amount of the trunnions 50a, 52a, 54a, 56a are connected to the recess cam 67 and the link 67a. Thus, the amount of movement in the axial direction is converted to the amount of movement through the shaft, and this amount of movement in the axial direction is introduced as a feedback amount.
[0037]
That is, the amount of rotation of the trunnions 50a, 52a, 54a, 56a is proportional to the amount of tilt of the power rollers 18c, 18d and 20c, 20d, and feeding back the amount of rotation of the trunnions The amount of tilt is fed back.
[0038]
Line pressure generated by the hydraulic pump 69 is introduced from the introduction port 68 to the control valve 60, and the line pressure is supplied to the first port 68a or the second port 68b depending on the relative positional relationship between the sleeve 63 and the spool 64. Is done.
[0039]
The line pressure from the first port 68a and the second port 68b is supplied to the hydraulic actuators 50, 52, 54, and 56 through pipes 70a, 70b, 72a, 72b, 74a, 74b, 76a, and 76b. Supplied through. The hydraulic actuators 50, 52, 54, and 56 are configured such that the upper chamber A and the lower chamber B are separated by pistons 50c, 52c, 54c, and 56c, and higher hydraulic pressure is supplied to the upper chamber A than the lower chamber B. Accordingly, each trunnion 50a, 52a, 54a, 56a is moved downward, and on the contrary, higher hydraulic pressure is supplied to the lower chamber B than the upper chamber A, whereby each trunnion 50a, 52a, 54a is supplied. , 56a are moved upward.
[0040]
On the other hand, the hydraulic actuators 50 and 52 of the first toroidal transmission unit 18 and the hydraulic actuators 54 and 56 of the second toroidal transmission unit 20 respectively include one upper chamber A and the other lower chamber B and one lower chamber B and the other. The upper chamber A intersects and communicates, and the hydraulic actuators 50 and 54 and the hydraulic actuators 52 and 56 are operated in opposite directions. The upper chamber A of the hydraulic actuators 50 and 54 and the lower chamber B of the hydraulic actuators 52 and 56 are connected to the first port 68a of the control valve 60, and the lower chamber B and the hydraulic actuators 52 and 56 of the hydraulic actuators 50 and 54 are connected. The upper chamber A is connected to the second port 68 b of the control valve 60.
[0041]
The controller 100 receives a throttle opening signal 101, a vehicle speed signal 102, a cvt input rotation speed signal 103, an oil temperature signal 104, a shift range signal 105, and the like. Based on a predetermined shift map and a shift control law, A shift control command 106 is output to the step motor 61, and the sleeve 63 is moved according to the command value.
[0042]
Here, the flow of the oil temperature increase control by the controller 100 will be described based on the flowchart of FIG.
[0043]
In step 200, first, based on the shift position sensor or the shift range signal 105 from the park switch 94, the shift position of the select lever 95 at that time is determined. If it is determined that the shift position is in the parking range, the process proceeds to the next step 210. If it is outside the parking range, the routine of the oil temperature rise control is exited.
[0044]
In step 210, an oil temperature signal 104 from an oil temperature sensor (not shown) is captured and compared with a predetermined reference value. If it is determined that the oil temperature is lower than the reference value, the process proceeds to the next step 220. If the oil temperature is higher than the predetermined value, the routine exits from the oil temperature increase control routine.
[0045]
In step 220, an idle speed increase request signal 107 is output to the engine. In the next step 230, the engagement signal 108 is output to the forward clutch 44 of the forward / reverse switching device 40, the forward clutch 44 is directly connected to the output rotating shaft 14, and the release signal 109 is output to the reverse brake 46. . By doing in this way, the turbine runner 12b of the torque converter 12 and the torque transmission shaft 16 rotate in the same direction.
[0046]
At this time, since the select lever 95 is in the parking range, the barking gear 90 and the parking ball 91 are engaged and the tire side (not shown) is locked, so the countershaft 30, the input gear 30a, the output gear 28, The torque transmission shaft 16 is also unable to rotate via the first and second output disks 18b and 20b, the power rollers 18C and 18d and 20c and 20d, and the first and second input disks 18a and 20a. Therefore, the turbine runner 12b is also stopped by the clutch control.
[0047]
On the other hand, since the pump impeller 12a is connected to an engine (not shown), it is rotating at the same speed as the engine. From the above, the rotational speed difference between the pump impeller 12a and the turbine runner 12b becomes equal to the engine speed, and almost all of the energy generated in the engine is converted into heat energy in the torque converter 12 to rapidly increase the oil temperature. It will be.
[0048]
Instead of the above-described clutch control, the forward clutch 44 is released, the reverse brake 46 is engaged, and the ring gear 42a of the planetary gear mechanism 42 is engaged with the housing 22, whereby the turbine runner 12b and the torque transmission shaft are engaged. It may be in a state in which 16 rotates in the opposite direction, or both may be fastened to a locked state. (In any case, since the shift position of the select lever 95 is parking, it is parked and the turbine runner 12b cannot rotate.)
Further, in the present embodiment, the process proceeds to step 240, and the warning light lighting signal 110 is output from the controller 100 as means for notifying the driver that the oil temperature increase control described above is being performed. A warning light (not shown) is turned on or flashed by the warning light lighting signal 110. In addition to this, for example, it is conceivable to notify the driver by blinking a lamp of an indicator indicating the shift position.
[0049]
The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the present invention. Are included in the present invention. For example, without controlling the clutch or brake of the forward / reverse switching device, the control only for increasing the idle rotational speed of the engine, or conversely, without controlling the idle rotational speed of the engine, It is possible to raise the temperature of the hydraulic oil only by controlling the brake, and it is conceivable to install a dedicated heater in an oil pan or the like that is usually installed at the bottom of the continuously variable transmission mechanism.
[0050]
Further, in the present embodiment, as a means to inform the driver that the operating oil is in a state of being heated, it is exemplified warning light, if it is possible to inform that it is the control state of the present invention to the driver Those using other means such as acoustic, optical, mechanical and vibration are also included in the present invention.
[0052]
【The invention's effect】
As described above, the traction oil for transmitting the torque is, the hydraulic oil for lubrication and gear shift control between components, noted that is also used as a hydraulic fluid in the torque converter, the oil temperature detected The temperature of the hydraulic oil is measured using the means, and if it is determined that the oil temperature is lower than a predetermined reference value, the engine idle speed is increased, and the pump impeller and the turbine runner in the torque converter are increased. Since the slip is increased and the rise of the hydraulic oil temperature is accelerated, an effect that the hydraulic oil flow rate for responding to the required shift control can be secured is obtained.
[0053]
Further, to determine whether there where the shift position, when in the parking range, by controlling the clutches and brakes of the forward-reverse switching device, and a torque transmission shaft of the turbine runner and the continuously variable transmission mechanism directly coupled As a result, the turbine runner cannot be rotated and the rotational speed difference from the pump impeller is increased to convert most of the energy generated by the engine into heat energy in the torque converter. The hydraulic oil temperature can be quickly raised, and an effect is obtained that the hydraulic oil flow rate for responding to the required shift control can be secured quickly.
[Brief description of the drawings]
FIG. 1 is an overall view of a toroidal continuously variable transmission according to the present invention.
FIG. 2 is a detailed view of a select lever in the present invention.
FIG. 3 is a cross-sectional view of a toroidal continuously variable transmission according to the present invention.
FIG. 4 is a flowchart of control in the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Toroidal type continuously variable transmission 12 Torque converter 12a Pump impeller 12b Turbine runner 12c Stator 12d Lock-up clutch 16 Torque transmission shaft 18 First toroidal transmission unit 20 Second toroidal transmission unit 18a, 20a Input disk 18b, 20b Output disk 18c, 18d, 20c, 20d Power roller 30 Countershaft 40 Forward / reverse switching device 50, 52, 54, 56 Hydraulic actuator 60 Shift control valve 61 Step motor 67 Precess cam 100 Control unit

Claims (2)

An input disk, an output disk arranged coaxially therewith, a plurality of power rollers pressed against the opposing surfaces of these disks, and a roller that supports the power roller in a rotatable manner and is capable of tilting and can be displaced vertically In a toroidal continuously variable transmission having a support member, a hydraulic cylinder device that displaces the roller support member in the vertical direction, and a shift control valve that controls the hydraulic cylinder device,
Oil temperature detection means for hydraulic oil, oil temperature determination means for comparing the oil temperature detected by the oil temperature detection means with a predetermined value set in advance, and determining that the temperature is lower than the predetermined value, and the oil temperature determination Hydraulic oil heating means operating on the basis of the results of the means;
The hydraulic oil heating means has shift position detection means, and when the signal from the shift position detection means is a parking range, the clutch runner in the forward / reverse switching device is controlled to control the turbine runner of the torque converter. And the torque transmission shaft of the continuously variable transmission mechanism are directly connected to increase the slip of the pump impeller and the turbine runner in the torque converter to increase the temperature of the hydraulic oil. Control device for toroidal type continuously variable transmission. Wherein the hydraulic oil heating means, the control device of the toroidal type continuously variable transmission according to claim 1, characterized in that it comprises a means for notifying the driver that are in a state in which hydraulic oil is heated.

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