JP3840079B2 - Anti-slip device for toroidal type continuously variable transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a device for preventing slipping in a power roller contact ellipse of a toroidal-type continuously variable transmission.
[0002]
[Prior art]
A toroidal-type continuously variable transmission usually has a power roller that is constricted between input and output cone disks arranged coaxially and is configured to transmit the rotation of the input and output cone disk to the output cone disk via the power roller. It is normal. Such transmission is performed by shearing an oil film sandwiched between contact ellipses between the input / output disk cone disk and the power roller.
[0003]
By the way, the thickness of the oil film in the contact ellipse depends on the temperature of the contact ellipse, and the thickness of the oil film increases because the viscosity of the hydraulic oil is high at low temperatures. As the oil film thickness of the contact ellipse increases, the area of the contact ellipse increases and the surface pressure here decreases, so that the traction force between the input / output cone disk and the power roller decreases. As a conventional technique for preventing slip generated due to the reduction in the traction force, for example, a technique described in Japanese Patent Application Laid-Open No. 2001-98965 is known.
[0004]
In this publication, the slippage of the power roller is prevented by performing torque smoothing control and N range upper limit engine rotation control for a predetermined time determined by the oil temperature (oil temperature in the oil pan) at the time of starting the engine. Is realized.
[0005]
[Problems to be solved by the invention]
However, the above-described prior art has the following problems. That is, when the engine is started and the oil temperature of the oil pan is low, it is uniquely estimated that the temperature of the rolling surface is low. Even when the engine is started, the oil temperature is low and the temperature of the rolling surface is low. In particular, no consideration is given to the situation where the temperature of the rolling surface changes, in particular, the temperature of the rolling surface changes under the influence of the outside air temperature.
[0006]
FIG. 8 is a characteristic diagram showing the relationship between engine water temperature, oil pan temperature, and rolling surface temperature. As shown in the figure, when the torque smoothing control and the N range upper limit engine rotation control are performed when the temperature is equal to or lower than the control start temperature T, the actual rolling contact surface temperature becomes the control start temperature when control is performed based on the oil pan oil temperature. In spite of being sufficiently higher than the above, the above control is performed at the point A where the oil pan temperature becomes T.
[0007]
That is, even when the oil temperature is low, the rolling surface temperature is high to some extent, and the torque smoothing control to prevent slipping is used in the prior art, even when the engine is started, which does not cause the power roller to slip. There was a problem that the running performance was deteriorated.
[0008]
The present invention has been made paying attention to the above-mentioned problems, and the purpose thereof is to accurately detect the temperature in the power roller contact ellipse of the toroidal-type continuously variable transmission, thereby deteriorating traveling performance. An object of the present invention is to provide a slip prevention device for a toroidal continuously variable transmission that can prevent slippage of a power roller.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, there is provided a combination of an engine having an electronically controlled throttle valve capable of changing the relationship of the throttle opening with respect to the accelerator pedal depression amount, and a toroidal continuously variable transmission. When the surface temperature of the power roller contact ellipse of the toroidal continuously variable transmission is below a predetermined value, the engine output is prevented so that the power roller of the toroidal continuously variable transmission does not slip. In the anti-slip device for a toroidal-type continuously variable transmission that restricts, a bearing support member that is adjacent to the toroidal transmission unit and is fixed to the transmission housing and rotatably supports the transmission output shaft via a bearing is provided. The surface temperature of the bearing support member on the outer peripheral side of the bearing support portion adjacent to the toroidal transmission portion. Characterized in that a temperature detecting means for output.
[0012]
Operation and effect of the invention
The anti-slip device for a toroidal continuously variable transmission according to claim 1 is adjacent to the toroidal transmission and is fixed to the transmission housing and rotatably supports the transmission output shaft via a bearing. By providing a bearing support member and providing temperature detection means for detecting the surface temperature on the outer peripheral side of the bearing support portion of the bearing support member and adjacent to the toroidal transmission portion , as in the prior art Since it is less affected by the outside air temperature than detecting the temperature inside the oil pan, the temperature drop characteristic is equivalent to the contact ellipse of the power roller. Therefore, the surface temperature of the power roller contact ellipse can be accurately estimated. Thereby, it is possible to prevent the deterioration of running performance by avoiding performing the anti-slip control although the surface temperature at which the power roller does not slip is ensured.
[0015]
The engine 1 includes an electronically controlled throttle valve 5 that is not linked to an accelerator pedal 3 that is operated by the driver, but is disconnected from the accelerator pedal 3 so that the opening degree is electronically controlled by the throttle actuator 4. By setting the rotational position corresponding to the target throttle opening y, the throttle valve 5 is set to the target throttle opening y, and the output of the engine 1 can be controlled by factors other than the accelerator pedal operation.
[0016]
The target throttle opening y is calculated by an engine controller (ECU) 6, and the engine controller 6 further executes a torque smoothing control and an N range upper limit engine rotation control program to control the throttle opening of the engine 1. In addition, the slip prevention of the toroidal type continuously variable transmission 2 is performed through fuel cut control. For this reason, the engine controller 6 includes a signal from the accelerator sensor 7 that detects the depression amount x of the accelerator pedal 3, a signal from the throttle opening sensor 8 that detects the throttle opening TVO of the throttle valve 5, and a toroidal type sensor. From a signal from the N range switch 9 that is turned on while the step transmission 2 is in the neutral (N) range where power transmission is not performed, and from an idle switch 10 that is turned on while the accelerator pedal 3 is released. , A signal from the vehicle speed sensor 11 that detects the vehicle speed VSP, a signal from the engine rotation sensor 12 that detects the engine speed Ne, and a signal from the intake air amount sensor 13 that detects the intake air amount Q of the engine 1 And a signal from the temperature sensor 14 for detecting the temperature in the toroidal type continuously variable transmission 2.
[0017]
The engine controller 6 commands the target throttle opening y to the throttle actuator 4 as a calculation result based on these input information, and also instructs the fuel cut device 1a of the engine 1 to appropriately perform the fuel cut operation, thereby toroidal-type continuously variable transmission. This is to prevent the machine 2 from slipping.
[0018]
FIG. 2 is a flowchart showing torque smoothing control and N-range upper limit engine rotation control executed in the embodiment of the present invention. The torque smoothing control is the same as the control described in Japanese Patent Application Laid-Open No. 2001-98965, and a description thereof will be omitted.
[0019]
In step 31, it is determined whether or not the N-range switch is on. If it is on, the process proceeds to step 32. Otherwise, this step is repeated.
[0020]
In step 32, it is determined whether or not the torque smoothing control time after start determined by the control time determination flow shown in FIG. 3 is reached, and if it is during the torque smoothing control time after starting, the process proceeds to step 33; Proceed to 35. Here, when describing a control time determination map in FIG. 3, the starting-period shift-apparatus temperature by the temperature sensor 1 4 provided within the transmission are detected current in the transmission temperature, based on the detected temperature map From this, the fuel cut / throttle fully closed control time at the time of selection and the torque smoothing control time after engine start are determined.
[0021]
In step 33, N range upper limit engine rotation control and torque smoothing control are performed based on the determined control time.
[0022]
In step 34, it is checked again whether or not the N range switch is ON. If it is the N range, the process proceeds to step 32.
[0023]
In step 35, it is determined whether or not the idle switch is on. If it is on, the process proceeds to step 36. Otherwise, the process proceeds to step 33. Here, it is possible to determine whether or not the idle switch is on when the N range switch is on in step 31 and the accelerator is depressed but the N range switch is stuck. This is because it is necessary to perform N range upper limit engine rotation control.
[0024]
In step 36, torque smoothing control is performed.
[0025]
In step 37, it is determined whether or not the vehicle speed is less than a preset vehicle speed VSP _S (= 10 km / h). If it is less than VSP _S , the process proceeds to step 38. Otherwise, the process proceeds to step 40. That is, since it is determined that the travel range is in step 34, it is determined whether or not the vehicle is in a low vehicle speed range where the power roller slips.
[0026]
In step 38, it is determined whether the fuel cut / throttle fully closed control time has elapsed after selection, or whether Z seconds have elapsed since the Yrpm rise from the lowest engine speed after the N-range switch is turned off. If not, the process proceeds to step 40. If not, the process proceeds to step 39. Here, “when the N range switch rotational speed Ne increases by the set amount Yrpm and a predetermined time Z seconds has elapsed” means that the power transmission is enabled by the selection operation from the neutral range to the traveling range and the engine rotational speed is reached. It means that the driver feels that the engine speed has decreased, and then desires to start and then depresses the accelerator pedal for a predetermined time to increase the engine speed.
[0027]
In step 39, the fuel cut / throttle full-closed control at the time of selection is performed, and the routine proceeds to step 34.
[0028]
The torque smoothing control is the same as the control described in Japanese Patent Application Laid-Open No. 2001-98965, and a description thereof will be omitted. Here, in order to perform slip prevention, how to accurately estimate the temperature of the rolling surface is an issue, so the temperature sensor will be described in detail below.
[0029]
( Reference Example 1 )
FIG. 4 is a cross-sectional view of the toroidal continuously variable transmission in Reference Example 1 . The first toroidal transmission unit 51 and the second toroidal transmission unit 52 are composed of a pair of power rollers 1L and 1R sandwiched between the input disk 20 and the output disk 21. These power rollers 1L and 1R are supported by a trunnion (not shown) so as to be tiltable and rotatable. The tilting motion of the power rollers 1L and 1R is a rotational motion that changes the contact radius with the input / output disk. Each trunnion is displaced in the axial direction of the trunnion by an actuator (not shown), and the power rollers 1L and 1R are tilted in accordance with the displacement to change the gear ratio.
[0030]
Angular ball bearings 59 are provided on the back surfaces of both output disks 21 and 21A. The angular ball bearing 59 is fixed to the inner periphery of the gear housing assembly 28 fixedly supported by the casing 19 and rotatably supports the output disks 21 and 21A and the output gear 26 which are integrated by the cylindrical portion 26A. . The gear housing assembly 28 houses a gear 27 a that transmits rotation to the output gear 26 and the counter shaft 30 of the toroidal transmission unit.
[0031]
Rotation input from a power source (not shown) is transmitted from the input disks 20 and 20A that rotate integrally with the transmission input shaft 25 to the output disks 21 and 21A via the power rollers 1L and 1R. A transmission output shaft that rotates integrally with the gear 46a via a counter shaft 30 that rotates with the gear 27a and a gear 32 that is provided on the counter shaft 30 via an idler gear (not shown). 46.
[0032]
In the vicinity of the transmission output shaft 46 side end portion of the transmission input shaft 25, disc springs 40 and 41 and a loading nut 43 for pressing the input disk 20A to the left side in the figure are provided, and further, the transmission input shaft end portion is shifted. It is supported by the shaft center part of the machine output shaft 46. Further, the transmission output shaft 46 is a tapered roller bearing 44 provided in a bearing support portion 45a which is an axial center portion of a retainer 45 press-fitted into the casing 19 and extends substantially perpendicular to the right side in the drawing in the axial direction. It is rotatably supported through
[0033]
(Temperature sensor mounting position)
A temperature sensor 14 is provided on the side surface of the gear housing assembly 28 on the first toroidal transmission 51 side and on the upper side facing the oil pan mounting side provided in the lower part of the casing 19 in the figure. As shown in the side view of the temperature sensor 14 viewed from the first toroidal transmission 51 side in FIG. 5 , the temperature sensor 14 is disposed on the outer circumferential side of the output disk 21 in the casing recess 19a for mounting the gear housing assembly 28. Has been. By providing the temperature sensor in the dead space in this manner, it is possible to prevent an increase in axial and radial dimensions, and it can be applied to a conventional toroidal continuously variable transmission without increasing costs. . The temperature sensor 14 directly detects the temperature on the upper side of the gear housing 28 that is not easily affected by the outside air temperature. When used as a temperature for estimating the rolling surface used in the anti-slip device of the present invention, More accurate temperature information can be provided.
[0034]
(First embodiment) FIG 6 is a sectional view of a toroidal type continuously variable transmission in the first embodiment according to the present invention. The description of the same configuration as that of Reference Example 1 is omitted, and only different points will be described in detail.
[0035]
(Temperature sensor mounting position)
A temperature sensor 15 is provided on the outer peripheral side of the bearing support portion 45 a and the toroidal transmission mechanism portion side with the retainer 45 press-fitted into the casing 19. The temperature sensor 15 is accommodated in an upper side facing the oil pan mounting side provided in the lower part of the casing 19 in the figure, and surrounded by the side wall of the retainer 45, the disc spring 41 and the loading nut 43. Has been. By providing the temperature sensor in the dead space in this manner, it is possible to prevent an increase in axial and radial dimensions, and it can be applied to a conventional toroidal continuously variable transmission without increasing costs. . Further, the temperature sensor 1 5 detects the temperature of the susceptible retainer 45 the influence of the outside air temperature directly when used as a temperature for estimating a rolling surface for forming the slip prevention device of the present invention, more accurate High temperature information can be provided.
[0036]
(Third embodiment)
FIG. 7 is a cross-sectional view illustrating a configuration of an infinitely variable transmission continuously variable transmission according to Reference Example 2 . In the reference example 1 and the first embodiment, the toroidal type continuously variable transmission applied to the rear wheel drive vehicle has been described, but in the reference example 2 , the infinite gear ratio continuously variable transmission applied to the front wheel drive vehicle is described. To do.
[0037]
First, the structure will be described. 60 is a toroidal transmission, 64 is a low clutch, 65 is a planetary gear mechanism, 67 is a high clutch, and 69 is a differential. The rotation input from the transmission input shaft 61 is output from the output gear 75 provided on the outer periphery of the output disk 73 of the toroidal transmission 60 to the gear 66 connected to the sun gear of the planetary gear mechanism 65. The gear 61 a that rotates integrally with the transmission input shaft 61 is output to the pinion carrier of the planetary gear mechanism via the intermediate gear 62 and the low clutch 64. The gear 66 connected to the sun gear and the transmission output shaft 68 can be connected and disconnected by a high clutch 67.
[0038]
The infinitely variable transmission of the front wheel drive vehicle is configured by connecting / disconnecting the low clutch 64 and the high clutch 67 and shifting the toroidal transmission.
[0039]
A temperature sensor 16 is provided in a partition wall 70 between the power source and the toroidal transmission unit (not shown). This temperature sensor 16 is provided on the outer peripheral side of the input shaft support portion 70a that protrudes substantially perpendicular to the axial direction so as to rotatably support the transmission input shaft 61, and on the upper side facing the oil pan mounting portion. Yes. By providing the temperature sensor in the dead space in this manner, it is possible to prevent an increase in axial and radial dimensions, and it can be applied to a conventional toroidal continuously variable transmission without increasing costs. . Further, the temperature sensor 16 directly detects the temperature of the partition wall 70 which is not easily affected by the outside air temperature, and is more accurate when used as a temperature for estimating the rolling surface used in the anti-slip device of the present invention. High temperature information can be provided.
[0040]
As described above, in the slip control device for the toroidal type continuously variable transmission in the first embodiment of the present invention and the reference examples 1 and 2 , the temperature sensors 14, 15 and 16 are provided at the above-described positions. The temperature of the power roller rolling surface can be accurately estimated, and the slip prevention control of the power roller can be performed without impairing running performance. In addition, although the temperature sensor attachment position was demonstrated in 1st Example and Reference Examples 1 and 2 , it is not restricted to the structure of 1st Example and Reference Examples 1 and 2 , Other toroidal type continuously variable transmissions Needless to say, the same applies to the configuration.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory diagram of a vehicle power train and a control system showing a slip prevention device for a toroidal-type continuously variable transmission according to an embodiment of the present invention.
FIG. 2 is a flowchart of engine output restriction control and torque smoothing control executed by the engine controller for preventing slipping of the toroidal-type continuously variable transmission in the embodiment.
FIG. 3 is a map diagram illustrating a time for torque smoothing control after engine start for limiting engine output and a time for fuel cut / throttle fully closed control during selection;
4 is a cross-sectional view of a toroidal continuously variable transmission in Reference Example 1. FIG.
FIG. 5 is a side view of the toroidal-type continuously variable transmission according to Reference Example 1 as viewed from the first toroidal transmission unit side.
FIG. 6 is a cross-sectional view of the toroidal continuously variable transmission in the first embodiment.
7 is a cross-sectional view of a continuously variable transmission with an infinite gear ratio in Reference Example 2. FIG.
FIG. 8 is a characteristic diagram showing a comparison between the relationship between the engine water temperature, the oil temperature in the oil pan, the rolling surface temperature, and the temperature sensor.

Claims (1)

An engine with an electronically controlled throttle valve capable of changing the relationship of the throttle opening to the accelerator pedal depression amount;
A power roller for a toroidal-type continuously variable transmission, comprising a power train for a vehicle that is combined with a toroidal-type continuously variable transmission, and when the surface temperature of the power roller contact ellipse of the toroidal-type continuously variable transmission is below a predetermined temperature In the anti-slip device of the toroidal type continuously variable transmission that limits the engine output so that the engine does not slip,
A bearing support member that is adjacent to the toroidal transmission unit and is fixed to the transmission housing and rotatably supports the transmission output shaft via the bearing,
A slip prevention for a toroidal continuously variable transmission, characterized in that a temperature detecting means for detecting the surface temperature is provided on the outer peripheral side of the bearing support part of the bearing support member and adjacent to the toroidal transmission part. apparatus.

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