JP7222791B2 - Continuously variable transmission and control method for continuously variable transmission - Google Patents

Description

The present invention relates to a continuously variable transmission and a control method for the continuously variable transmission.

As a continuously variable transmission capable of steplessly adjusting the gear ratio by changing the contact diameter of the belt with respect to a pair of variable pulleys, a plurality of lateral members, which are media or elements for transmitting power, are formed into rings or annular bands. It is known to provide a belt that is bounded by: Patent Literature 1 discloses a belt that is applied to such a continuously variable transmission and that includes an element that is substantially U-shaped. This element has a base portion and a pair of pillar portions extending in the same direction from opposite ends of the base portion, and is attached to one ring through openings between the pillar portions.

Special table 2017-516966 (paragraphs 0025 to 0027)

In a continuously variable transmission that transmits power through elements, the gap between adjacent elements (called "end play") may increase, increasing the total amount of end play over the entire circumference of the belt. In such a situation, local concentrations of endplay can lead to isolated elements. Further application of lateral force to the isolated element may cause the element to fall off the ring. In Document 1, a hook is provided on the pillar portion of the element, and the element is locked to the ring by this hook. This is because the lock by the hook is released by moving to . Enlargement of the end play is caused by elongation of the ring, compression of the element by other elements, and abrasion of the elements due to rubbing against each other.

The present invention has been made in view of such problems, and an object of the present invention is to suppress dropout of an element.

A continuously variable transmission according to one aspect of the present invention is a continuously variable transmission mounted on a vehicle, comprising a primary pulley, a secondary pulley, and a belt stretched over the primary pulley and the secondary pulley, comprising a ring and a plurality of elements bound by the ring, each of which has a receiving portion opening in the radial direction of the belt and receives the ring in the receiving portion; and a controller. composed of The continuously variable transmission further includes an oil supply device for blowing oil to the end play concentrated portions of the plurality of elements. The oil supply device sprays oil onto the elements of the plurality of elements in a direction opposite to a direction in which the elements are displaced, and oil is applied to a portion opposite to a portion where the receiving portion opens. and/or to spray the oil. The controller controls the oil supply device when detecting a predetermined operating state, which is an operating state of the vehicle and an operating state in which there is a high possibility that the elements of the plurality of elements will come off, A control unit is provided for executing oil supply control to increase the amount of oil blown to the end-play concentration point compared to when the predetermined operating state is not detected.

According to another aspect of the present invention, there is provided a continuously variable transmission control method corresponding to the above aspect of the continuously variable transmission.

According to these aspects, even in an operating state in which there is a high possibility of the element falling off, the element is supported against falling off in a preventative manner by increasing the amount of oil blown to the end play concentration point. In addition, it is possible to suppress lateral displacement of the element. Therefore, according to these aspects, it is possible to suppress the falling off of the element.

FIG. 1 is a schematic diagram showing the configuration of a power transmission system of a vehicle equipped with a continuously variable transmission according to one embodiment of the invention. FIG. 2 is a schematic diagram showing the configuration of the same continuously variable transmission. FIG. 3 is a cross-sectional view showing the configuration of a belt provided in the same continuously variable transmission. FIG. 4 is an explanatory view showing a method of assembling the same belt (procedure of mounting elements). FIG. 5 is an explanatory diagram schematically showing a state in which end plays are concentrated. FIG. 6 is a diagram showing the oil supply device together with the elements. FIG. 7 is a flow chart showing an example of control according to an embodiment of the present invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

(Configuration of vehicle drive system)
FIG. 1 schematically shows the overall configuration of a power transmission system (hereinafter referred to as "drive system") P1 of a vehicle equipped with a continuously variable transmission 2 according to one embodiment of the invention.

A drive system P1 according to the present embodiment includes an internal combustion engine (hereinafter simply referred to as "engine") 1 as a drive source of the vehicle. A transmission 2 is provided. The engine 1 and the continuously variable transmission 2 can be connected via a torque converter. The continuously variable transmission 2 converts rotational power input from the engine 1 at a predetermined gear ratio, and outputs the converted power to drive wheels 5 via a differential gear 3 .

The continuously variable transmission 2 includes a primary pulley 21 on the input side and a secondary pulley 22 on the output side as transmission elements. The continuously variable transmission 2 includes a metal belt 23 stretched over a primary pulley 21 and a secondary pulley 22. By changing the ratio of the contact portion radii of the metal belt 23 between these pulleys 21 and 22, the gear ratio can be changed. Stepless change is possible.

Primary pulley 21 and secondary pulley 22 are provided coaxially with fixed sheaves 211 and 221 and axially movable along rotation center axes Cp and Cs of fixed sheaves 211 and 221. movable sheaves 212, 222. A fixed sheave 211 of the primary pulley 21 is connected to the input shaft of the continuously variable transmission 2, and a fixed sheave 221 of the secondary pulley 22 is connected to the output shaft. The gear ratio of the continuously variable transmission 2 is formed between the fixed sheaves 211, 221 and the movable sheaves 212, 222 by adjusting the pressure of hydraulic oil acting on the movable sheaves 212, 222 of the primary pulley 21 and the secondary pulley 22. is controlled by varying the width of the V-groove.

In this embodiment, an oil pump 6 powered by the engine 1 or an electric motor (not shown) is provided as a source of the operating pressure for the continuously variable transmission 2 . The oil pump 6 raises the pressure of the hydraulic oil stored in the transmission oil pan, and using this pressure as a source pressure, hydraulic oil at a predetermined pressure is supplied to the hydraulic chambers of the movable sheaves 212 and 222 via the hydraulic control circuit 7. supply. FIG. 1 shows the hydraulic supply path from the hydraulic control circuit 7 to the hydraulic chambers by dotted lines with arrows.

Rotational power output from the continuously variable transmission 2 is transmitted to the drive shaft 4 via the final gear train or sub-transmission (both not shown) set to a predetermined reduction ratio and the differential gear 3 to drive the vehicle. Rotate wheel 5.

(Control system configuration and basic operation)
Operations of the engine 1 and the continuously variable transmission 2 are controlled by an engine controller 101 and a transmission controller 201, respectively. Both the engine controller 101 and the transmission controller 201 are configured as electronic control units, and consist of a microcomputer equipped with a central processing unit (CPU), various storage devices such as RAM and ROM, input/output interfaces, and the like.

A detection signal from an operating state sensor that detects the operating state of the engine 1 is input to the engine controller 101 . The engine controller 101 performs predetermined calculations based on the operating state, and sets the fuel injection amount, fuel injection timing, ignition timing, and the like of the engine 1 . As driving state sensors, an accelerator sensor 111 that detects the operation amount of the accelerator pedal by the driver (hereinafter referred to as "accelerator opening"), a rotation speed sensor 112 that detects the rotation speed of the engine 1, and a temperature of the engine cooling water are detected. In addition to the cooling water temperature sensor 113 and the like, an air flow meter, a throttle sensor, a fuel pressure sensor, an air-fuel ratio sensor, and the like (none of which are shown) are provided.

The transmission controller 201 is communicably connected to the engine controller 101 via a CAN standard bus. The transmission controller 201 includes a vehicle speed sensor 241 for detecting the running speed of the vehicle and an input side rotation speed sensor 242 for detecting the rotation speed of the input shaft of the continuously variable transmission 2 in relation to the control of the continuously variable transmission 2 . , an output-side rotation speed sensor 243 that detects the rotation speed of the output shaft of the continuously variable transmission 2, an oil temperature sensor 244 that detects the temperature of the working oil of the continuously variable transmission 2, and a shift position sensor that detects the position of the shift lever. 245 or the like is input.

In this embodiment, in addition to the above, signals and information from the acceleration sensor 246, the steering angle sensor 247, the suspension stroke sensor 248, the camera sensor 249, the car navigation device 250, the brake sensor 251, the gradient sensor 252, etc. 201. The transmission controller 201 also receives information about the operating state of the engine 1 such as the accelerator opening from the engine controller 101 . Signals and information input to transmission controller 201 may be input via other controllers such as an integrated controller that integrates control of the vehicle.

Acceleration sensor 246 detects acceleration (hereinafter also referred to as "lateral acceleration ACCl") acting in the lateral direction (that is, horizontal direction and perpendicular to the straight-ahead direction of the vehicle) with respect to the vehicle body. In this embodiment, the extending direction of the metal belt 23, in other words, the horizontal direction perpendicular to the rotation center axes Cp and Cs of the primary pulley 21 or the secondary pulley 22 coincides with the straight traveling direction of the vehicle, and the circumferential direction of the metal belt 23. and the direction perpendicular to the radial direction coincides with the lateral direction of the vehicle. Therefore, the lateral acceleration detected by the acceleration sensor 246 indicates the magnitude of acceleration or force (that is, inertial force) acting laterally on the metal belt 23 or its power transmission medium element. The element is an element 231, which will be described later, and the lateral direction is the lateral direction L, which will be described later.

The steering angle sensor 247 detects the steering angle of the vehicle (hereinafter also referred to as "steering angle Astr"). In this embodiment, the rotation angle of the steering wheel with respect to the reference angular position (that is, the turning angle of the steering wheel) is detected as the steering angle.

Suspension stroke sensor 248 is provided as a means for detecting the attitude of the vehicle, and in this embodiment, comprises a pair of stroke sensors attached to suspension devices on both the left and right sides of the front or rear wheels. In this embodiment, lateral vibration (hereinafter sometimes referred to as "lateral vibration") occurring in the vehicle is determined based on the detection signal from the suspension stroke sensor 248, which is a pair of left and right stroke sensors. As the stroke sensor 248, stroke sensors may be attached to the left and right suspension devices of both the front wheels and the rear wheels, respectively, so that it is possible to eliminate the influence of sway or inclination in the longitudinal direction on the determination of the sway.

Suspension stroke sensor 248 can be realized by a displacement sensor that detects the displacement of a piston rod provided in the shock absorber, or by an angle sensor that detects the angle of a suspension arm.

Camera sensor 249 is provided as means for detecting the condition of the road or road surface on which the vehicle is currently traveling. By analyzing the image or video captured by the camera sensor 249, it is possible to determine the presence or absence of unevenness on the road surface and its size as the state of the road or road surface.

The car navigation device 250 has road map information and a built-in GPS sensor, and compares the current position of the vehicle acquired by the GPS sensor (for example, the absolute position indicated by latitude and longitude) with the road map information. to detect the position of the vehicle on the road map. In this embodiment, the car navigation device 250 replaces or complements the camera sensor 249 as other means for detecting road or road surface conditions.

The brake sensor 251 detects the depression force of the brake pedal. A slope sensor 252 detects a road slope. The road gradient is the gradient of the road at the vehicle position, and is positive when the road slopes upward in the vehicle driving direction, and negative when the road slopes downward in the vehicle driving direction. For example, when the vehicle is on an uphill road, the road gradient is positive in the forward (D) range because it is an upward gradient in the vehicle driving direction, and is positive in the reverse (R) range because it is a downward gradient in the vehicle driving direction. negative.

Transmission controller 201 determines the shift range selected by the driver based on the signal from shift position sensor 245 as basic control related to gear shifting, and continuously adjusts the shift range based on the degree of accelerator opening, the running speed of the vehicle, and the like. A target gear ratio of the transmission 2 is set. The transmission controller 201 uses the oil pressure generated by the oil pump 6 as a source pressure to apply a predetermined oil pressure to the movable sheaves 212 and 222 of the primary pulley 21 and the secondary pulley 22 according to the target gear ratio. , outputs a control signal to the hydraulic control circuit 7 .

(Structure of continuously variable transmission)
FIG. 2 shows the configuration of the continuously variable transmission 2 according to the present embodiment by a cross section taken along line xx shown in FIG.

In this embodiment, the continuously variable transmission 2 includes a pair of variable pulleys, specifically a primary pulley 21 and a secondary pulley 22, and a metal belt 23 stretched between the pair of pulleys 21 and 22. . FIG. 2 shows the movable sheave 212 of the primary pulley 21, the fixed sheave 221 of the secondary pulley 22, and the metal belt 23 for convenience of illustration in cross section. The continuously variable transmission 2 is of a push belt type, and the metal belt 23 has a plurality of elements 231, which are power transmission media, arranged in the plate thickness direction, and a ring 232 (sometimes called a "hoop" or a "band"). ) bound together.

FIG. 3 shows the configuration of the element 231 according to this embodiment by a cross section perpendicular to the circumferential direction of the metal belt 23 .

In this embodiment, the ring 232 of the metal belt 23 is one ring configured by stacking a plurality of ring members 232a to 232d, and a plurality of elements 231 are attached to this one ring 232 to form a metal belt. A belt 23 is constructed. Since there is one ring 232, the metal belt 23 according to this embodiment is sometimes called a mono-ring type metal belt or simply a "mono-belt." Although FIG. 3 shows a case where there are four ring members (232a to 232d), it goes without saying that the number of ring members is not limited to this.

The element 231 generally comprises a base portion 231a and a pair of side portions 231b, 231b extending in the same direction perpendicular to the extending direction of the base portion 231a. None. The base portion 231a, also called a saddle portion, has a length that traverses the ring 232, and has contact surfaces for the sheaves 211, 212, 221, 222 of the primary pulley 21 and the secondary pulley 22 at both ends thereof. ing. The extending direction of the base portion 231 a is the width direction of the element 231 and coincides with the lateral direction L of the metal belt 23 . The side portions 231 b are also called pillar portions, and are connected to the base portion 231 a on each side of the ring 232 . A receiving portion 231r for the element 231 that opens in a direction perpendicular to the lateral direction L, that is, in the radial direction R of the metal belt 23 is formed by the inner surfaces of the pair of side portions 231b, 231b facing each other and the upper surface of the base portion 231a. . In the present embodiment, the opening direction of the receiving portion 231r is outward with respect to the radial direction R of the metal belt 23 . The element 231 is attached to the ring 232 from the inner peripheral side of the metal belt 23 in a state in which the ring 232 is received by the receiving portion 231r.

The element 231 has hooks or clamping pieces f protruding inward from the inner surface of the left and right side portions 231b forming the receiving portion 231r. A ring 232 is held between f. The element 231 has a pair of cutouts n on both the left and right sides 231b, 231b that partially expand the space of the receiving portion 231r in the lateral direction L. The notch n gives flexibility to the hook f, applies a force to hold down the ring 232, and forms a space for the ring 232 to escape when the element 231 is attached.

4(a) to 4(c) show a method of assembling the metal belt 23, more specifically, a procedure of attaching the element 231 to the ring 232 in chronological order. For convenience of illustration, FIG. 4 shows the procedure with the ring 232 in a different orientation, but it goes without saying that the orientation of the element 231 is changed in actual mounting.

First, the element 231 is placed on the inner peripheral side of the ring 232 with the element 231 inclined with respect to the ring 232 , and one side edge of the ring 232 is inserted into the receiving portion 231 r of the element 231 . Then, the element 231 is moved so that the base portion 231a is brought closer to the ring 232, and as shown in FIG. The side edge of the ring 232 reaches the notch n through the gap between the hook) f provided on the portion 231b.

Next, as shown in FIG. 4(b), the element 231 is rotated around the portion of the ring 232 located between the base 231a and the hook f (in the state shown in the figure, it is rotated counterclockwise). ) to eliminate the tilt of element 231 with respect to ring 232 . In this state, the element 231 is parallel to the ring 232 with the base 231a.

After making the base 231a of the element 231 parallel to the ring 232, as shown in FIG. (in the state shown in the figure, the element 231 is moved to the left), and the ring 232 is arranged at the center of the base portion 231a. This completes the mounting of one element 231 .

The metal belt 23 is completed by repeating such a procedure for all the elements 231 over the entire circumference of the metal belt 23 . Due to the tension of the ring 232, the front and rear elements 231 are bound together by the engagement of the protrusion p (FIG. 3) provided on the front surface of the element 231 and the recess provided on the rear surface of the adjacent element 231. .

Here, in the continuously variable transmission 2 using the element 231 as a power transmission medium, the end play EP, which is the gap between the adjacent elements 231, may expand and the total amount of the end play EP over the entire circumference of the metal belt 23 may increase. be. Specifically, when the ring 232 that bundles the elements 231 is stretched due to elastic or plastic deformation, the element 231 is pressed and crushed by another element 231, or the elements 231 are rubbed against each other and worn. This is the case when

If the end play EP concentrates locally in such a state, the element 231 may become isolated. When a force is applied to the isolated element 231 in a direction perpendicular to the circumferential direction and the radial direction R of the metal belt 23 (that is, in the lateral direction L), the element 231 moves in the lateral direction L with respect to the ring 232 . move to Therefore, there is a concern that the element 231 may drop out of the ring 232 by the reverse procedure of the procedure previously described with reference to FIG.

In this way, the dropout of the element 231 can occur when the three conditions of an increase in the total amount of the endplay EP, concentration of the endplay EP, and movement of the element 231 in the lateral direction L are satisfied.

Therefore, when at least one of these three conditions is satisfied, the possibility of the element 231 falling off is higher than when all three conditions are not satisfied and there is no possibility of the element 231 falling off. . Also, the more the number of conditions that are satisfied among these three conditions, the higher the possibility that the element 231 will fall off.

A driving state of the vehicle in which at least one of these three conditions is satisfied is a driving state in which the element 231 is likely to be dropped, and the element 231 is more likely to be dropped than when all three conditions are not met. It is considered to be a highly probable operating state.

FIG. 2 shows a state in which the end play EP concentrates, and FIG. 5 schematically shows an enlarged view of the portion of the metal belt 23 where the end play EP concentrates for easy understanding. In FIG. 2, the end play EP is concentrated in areas A and B indicated by dotted lines on the metal belt 23 .

In the present embodiment, the opening direction of the element 231, specifically, the receiving portion 231r of the element 231 is outward with respect to the radial direction R of the metal belt 23. Therefore, the receiving portion of the element 231 of the metal belt 23 In the part where 231r faces downward in the vertical direction, in other words, in the part below the straight line X connecting the rotation center axis Cp of the primary pulley 21 and the rotation center axis Cs of the secondary pulley 22, the end Even if a play EP occurs, the dropout of the element 231 is suppressed. On the other hand, there is a possibility that the part where the receiving part 231r faces upward may come off.

Furthermore, the force applied to the metal belt 23 from the pulleys 21 and 22 in the upper portion of the metal belt 23 tends to cause end play EP in the ranges A and B shown in FIG. In this case, when the element 231 advances in the direction in which the element 231 is sandwiched between the sheaves of the pulleys 21 and 22 according to the direction in which the pulleys 21 and 22 rotate, in other words, the metal belt 23 rotates between the pulleys 21 and 22. The case where the metal belt 23 advances in the direction of entering the space between the sheaves of the pulleys 21 and 22 and the case where the metal belt 23 advances in the direction of exiting the space between the sheaves of the pulleys 21 and 22 are distinguished. When advancing in the approach direction (range B in the example shown in FIG. 2), the element 231 is caught between the pulleys 21 and 22 even if the end play EP occurs, so falling off is suppressed. On the other hand, when moving in the escape direction (range A), there is no support from the pulleys 21 and 22, so there is a possibility that the element 231 will fall off when the end play EP occurs, and it is necessary to take countermeasures.

For example, during sudden braking, power is transmitted from the secondary pulley 22 to the primary pulley 21 in a direction opposite to the direction of rotation. At this time, in the range A, the metal belt 23 is stretched by the power in the direction opposite to the rotation direction, so the end play EP is concentrated. Further, in the range B, since the compression of the metal belt 23 that has been performing power transmission from the primary pulley 21 to the secondary pulley 22 in the push method is released, the end play EP is concentrated.

The concentration of the endplay EP not only creates a gap between adjacent elements 231, but also causes the protrusions p to move out of the recesses, disengage them, and move the elements 231 in the lateral direction L with respect to the ring 232. It can be seen that it is in a movable state.

In view of such circumstances, in the present embodiment, the continuously variable transmission 2 further includes an oil supply device OSD described below.

FIG. 6 is a diagram showing the oil supply device OSD. In FIG. 6 the oil supply device OSD is shown together with the element 231 . The oil supply device OSD is an oil supply device that blows oil to the end play concentrated portions of the plurality of elements 231, and has a plurality (three in this case) of oil injectors INJ1 to INJ3 and a valve V. As shown in FIG. A plurality of oil injectors INJ1-INJ3 are connected to the hydraulic control circuit 7 via oil passages H and are arranged to inject lubricating oil for the continuously variable transmission 2 toward the metal belt 23 .

The oil injectors INJ1 and INJ2 are provided at positions that spray lubricating oil onto the element 231 in the direction opposite to the direction in which the displacement occurs. The pressure of the lubricating oil sprayed from the sides by the oil injectors INJ1 and INJ2 against the element 231 suppresses the displacement of the element 231 itself. Therefore, movement of the element 231 in the lateral direction L is suppressed. The oil injector INJ3 is provided at a position that sprays lubricating oil onto the element 231 in a portion opposite to the opening direction of the receiving portion 231r.

A valve V is a flow control valve, and controls the flow rate of oil supplied to the plurality of oil injectors INJ1-INJ3 under the control of the transmission controller 201. FIG. A valve V is provided in an oil passage H that connects the plurality of oil injectors INJ1 to INJ3 and the hydraulic control circuit 7 . A valve V is provided as a common valve for the plurality of oil injectors INJ1 to INJ3.

The oil supply device OSD may have, for example, only the oil injectors INJ1 and INJ2 among the plurality of oil injectors INJ1 to INJ3, or only the oil injector INJ3. For example, the valve V may be provided individually for each of the plurality of oil injectors INJ1 to INJ3, or may be provided commonly for the oil injectors INJ1 and INJ2, while provided individually for the oil injector INJ3. may

A plurality of oil injectors INJ1 to INJ3 are provided so as to spray oil to the areas where the end play concentrates. FIG. 2 shows a plurality of oil injectors INJ1-INJ3 provided in this way. In FIG. 2, the oil injector INJ2 is provided behind the oil injector INJ1.

In this embodiment, in the area where the end play concentrates in the range B shown in FIG. No shedding of 231 occurs.

Therefore, in the present embodiment, a plurality of oil injectors INJ1 to INJ3 are provided for the area A where the end play concentrates. The end play concentrated portion of the range A is the end play concentrated portion formed at the most upstream position in the rotational direction in the contact area between the primary pulley 21 and the metal belt 23, and has a spread.

The oil injectors INJ1 and INJ2 are provided immediately after the position where the metal belt 23 starts to separate from the secondary pulley 22 in the rotation direction of the secondary pulley 22 . The oil injectors INJ1 and INJ2 can be configured, for example, by closed end pipes having one or more injection ports provided on the side.

The oil injector INJ3 is provided in a lower clearance space formed between the primary pulley 21, the secondary pulley 22 and the metal belt 23. The oil injector INJ3 can be composed of, for example, a closed end pipe having one or a plurality of injection ports on its side. The element 231 is supported by the pressure of the lubricating oil sprayed from below by the oil injector INJ3, and the dropout of the element 231 is suppressed.

The oil supply device OSD is controlled by the transmission controller 201 as follows.

FIG. 7 is a flowchart showing an example of control performed by the transmission controller 201. As shown in FIG. The transmission controller 201 is configured to have a control unit by being configured to execute the processing of this flowchart.

At step S1, the transmission controller 201 detects the driving state of the vehicle. In step S1, the driving state of the vehicle is detected based on the various input signals and input information described above with reference to FIG.

In step S2, the transmission controller 201 determines whether or not the operating state of the vehicle is a predetermined operating state. The predetermined driving state is a driving state in which there is a high possibility that the element 231 will fall off, and is a driving state of the vehicle that satisfies at least one of the three conditions regarding the element 231 falling off. Further, among the three conditions described above, the condition that the end play EP is concentrated is met, for example, during sudden braking as described above.

Therefore, the determination in step S2 can be made based on signals from the vehicle speed sensor 241 and the brake sensor 251, for example. During sudden braking, a larger braking torque is applied to the continuously variable transmission 2 than during normal deceleration, which promotes the collapse of the element 231 and the extension of the ring 232 due to compression, resulting in an increase in the total amount of end play EP. , is also satisfied.

If the determination in step S2 is affirmative, it is detected that the vehicle is in a predetermined driving state, and the process proceeds to step S3. Instead of being directly detected by a sensor that detects a parameter that indicates the predetermined operating state, the predetermined operating state is estimated based on a parameter that has a correlation with a parameter that indicates the predetermined operating state. may be If the determination in step S2 is negative, the process proceeds to step S4.

First, describing step S4, the transmission controller 201 controls the oil supply device OSD so that the amount of oil to be injected becomes the second oil amount M2. In step S4, by controlling the valve V, the amount of oil to be injected is set to the second oil amount M2.

In step S3, the transmission controller 201 controls the oil supply device OSD so that the amount of oil to be injected becomes the first oil amount M1. In step S3, by controlling the valve V, the amount of oil to be injected is set to the first oil amount M1.

The first oil amount M1 is set larger than the second oil amount M2. For this reason, in step S2, when a predetermined operating state is detected, the oil supply device OSD is controlled to increase the amount of oil blown to the point where the end play is concentrated compared to when the predetermined operating state is not detected. Oil supply control is executed. The first oil amount M1 and the second oil amount M2 are preset based on experiments or the like. The first oil amount M1 can be set in advance within a range in which dropout of the element 231 can be suppressed. The second oil amount M2 may be zero. After step S3 and step S4, the processing of this flowchart is temporarily terminated.

Next, main effects of this embodiment will be described.

The continuously variable transmission 2 is mounted on a vehicle. The continuously variable transmission 2 includes a primary pulley 21 and a secondary pulley 22, a metal belt 23 stretched over the primary pulley 21 and the secondary pulley 22, and a plurality of elements 231 bound by rings 232 and 232. a transmission controller 201; be. The continuously variable transmission 2 further includes an oil supply device OSD that sprays oil to the end play concentration locations of the plurality of elements 231 . The transmission controller 201 detects a predetermined operating condition of the vehicle, which is an operating condition in which the element 231 included in the plurality of elements 231, that is, the element 231 constituting the plurality of elements 231 is highly likely to fall off. In this case, by controlling the oil supply device OSD, oil supply control is executed to increase the amount of oil blown to the end play concentration point compared to when the predetermined operating state is not detected.

According to such a configuration, even in an operating state in which there is a high possibility that the element 231 will come off, by increasing the amount of oil blown to the point where the end play is concentrated, the element 231 can prevent the element 231 from coming off in a preventive manner. can be supported, and displacement of the element 231 in the lateral direction L can be suppressed. Therefore, according to such a configuration, it is possible to prevent the element 231 from coming off (effects corresponding to claims 1 and 5).

In this embodiment, the transmission controller 201 executes oil supply control when it detects an operating state in which the end play EP of the plurality of elements 231 concentrates as a predetermined operating state.

According to such a configuration, even if the possibility of the element 231 falling off increases due to the establishment of the condition that the end play EP is concentrated, the element 231 is prevented from falling off by blowing a large amount of oil to the point where the end play is concentrated. can be suppressed. In addition, according to such a configuration, the dropout of the element 231 is preventively dealt with before all the three conditions described above are satisfied, so the dropout does not occur as a result of delay in handling. Furthermore, according to such a configuration, it is possible to prevent the condition that the element 231 moves in the lateral direction L due to the oil that blows at the point where the end play is concentrated, so it becomes easier to prevent falling off ( Effect corresponding to claim 2).

Next, a modified example will be described.

Here, the end play occurrence area, which is the area where the end play EP that may cause the dropout of the element 231 occurs, can be defined as follows.

That is, the end play occurrence region solves the equation of motion regarding the balance of force applied to the metal belt 23, and the end play EP can be determined by calculating whether or not a force enough to cause is applied in the direction of opening the adjacent elements 231 . As described above, the end play generation area varies depending on the specifications of the power transmission system such as the radii of the pulleys 21 and 22 and the elastic modulus of the metal belt 23. Therefore, it is preferable to appropriately set the end play according to these parameters. preferable.

Such an end play occurrence region can be set in advance according to the operating state of the vehicle (specifically, accelerator opening and vehicle speed). Therefore, the transmission controller 201 may be configured to detect that the vehicle is in a predetermined driving state based on the accelerator opening APO and the vehicle speed VSP. In this case, when the accelerator opening and the vehicle speed are measured (that is, when both the accelerator opening and the vehicle speed are not 0), it is possible to determine whether or not the end play occurrence region exists.

The transmission controller 201 having such a configuration can further be configured to detect that the vehicle is in a predetermined driving state when the vehicle is on a slope. That is, the end play occurrence region can be set for, for example, the time when the vehicle is on a slope. Whether or not the vehicle is on a slope can be determined based on the longitudinal acceleration.

In this case, the transmission controller 201 further selects a travel range (a travelable range such as drive or reverse and a range other than a stop range such as parking or neutral) as the shift range of the continuously variable transmission 2. In addition, it can be configured to detect that it is in a predetermined operating state. That is, the end play occurrence region can be set for the case where the driving range is further selected.

Even if the possibility of the element 231 coming off increases, even with these configurations, it is possible to prevent the element 231 from coming off by blowing a large amount of oil onto the area where end play is concentrated (effects corresponding to claims 3 and 4).

As described above, if the element 231 is moved in the lateral direction L by applying a force in the lateral direction L to the element 231, the possibility of the element 231 coming off increases.

Therefore, the predetermined operating state may be, for example, an operating state in which a force in the lateral direction L is applied to the element 231 . Such a driving state can be detected by determining whether or not the lateral acceleration ACCl of the vehicle is equal to or greater than a predetermined value ACCthr.

As described above, the lateral acceleration ACCl is the acceleration that acts on the metal belt 23 and the element 231 in the lateral direction L due to the arrangement of the continuously variable transmission 2, and acts on the element 231 in the lateral direction L. Defines the magnitude of the acting force.

The lateral acceleration ACCl can be calculated by calculating the turning radius φtrn of the vehicle from the steering angle Astr and substituting the turning radius φtrn and the vehicle speed VSP into the following equation (1).

VSP/φtrn=ACCl (1)

Therefore, it is possible to detect, for example, based on signals from the vehicle speed sensor 241 and the steering angle sensor 247 that the element 231 is in a driving state in which the force in the lateral direction L is applied.

According to such a configuration, even if the element 231 moves in the lateral direction L and the possibility of the element 231 falling off increases due to the establishment of the condition, the element 231 can be prevented from It is possible to suppress the falling off of the In addition, according to such a configuration, preventive measures are taken, so there is no chance of falling off due to a delay in taking measures. Furthermore, according to such a configuration, it is possible to quickly suppress the displacement of the element 231 in the lateral direction L. Therefore, by suppressing the displacement of the element 231 before the remaining three conditions are satisfied, it becomes easier to prevent the element from falling off. Further, in this case, since the countermeasure is taken when the element 231 is in the operating state in which the force in the lateral direction L is actually applied, it is possible to avoid execution of unnecessary countermeasure (effect corresponding to claim 4).

In calculating the lateral acceleration ACCl, the radius of curvature of the road may be used instead of the turning radius φtrn. The radius of curvature of the road can be obtained from the car navigation device 250 as navigation information accompanying the road map information. In this case, it becomes possible to predict that the force in the lateral direction L will act on the element 231, so preventive measures are taken to prevent the condition that the element 231 moves in the lateral direction L from being satisfied. is also possible.

The operating state in which the force in the lateral direction L is applied to the element 231 may be detected based on the signal from the acceleration sensor 246 . In this case, the calculation load can be reduced by more directly detecting the lateral acceleration ACCl.

The operating state in which a force in the lateral direction L is applied to the element 231 includes a case where the lateral vibration is large and a force acts to cause a positional deviation in the lateral direction L on the element 231 . Therefore, such a driving state may be detected by determining the presence or absence of lateral vibration of the vehicle body and the magnitude thereof.

The presence or absence of rolling of the vehicle body and its magnitude can be detected based on the rolling display value Irll. The rolling indication value Irll is an index indicating the magnitude of the rolling in the lateral direction L occurring in the vehicle body.

Therefore, the driving state in which the force in the lateral direction L is applied to the element 231 can be detected by determining whether or not the roll indication value Irll is equal to or greater than a predetermined value Ithr.

In this embodiment, the difference (=ΔSTRr−ΔSTRl) between the change amount per unit time of the right suspension stroke amount STRr (hereinafter referred to as “suspension stroke change amount”) ΔSTRr and the left suspension stroke change amount ΔSTRl is calculated. This stroke change amount deviation Dstr is used as the roll display value Irll.

The stroke change amount deviation Dstr can be at least one of a difference in suspension stroke amount between the right front wheel and left front wheel and a difference in suspension stroke amount between the right rear wheel and left rear wheel. When both of these are used as the stroke change amount deviation Dstr, and accordingly as the rolling indication value Irll, the operating state in which the force in the lateral direction L is applied to the element 231 can be defined as the case where either of these is equal to or greater than the predetermined value Ithr.

From the above, when focusing on the presence or absence of lateral vibration of the vehicle body and its magnitude, it is possible to detect, based on the signal from the suspension stroke sensor 248, that the element 231 is in a driving state in which a force L in the lateral direction is applied. can.

In this case, it is determined whether or not a force is acting due to the condition of the road or road surface on which the vehicle is currently running. becomes possible. Further, by adopting the suspension stroke amounts STRr and STRl for calculating the rolling display value Irll that indicates the magnitude of the rolling, the rolling occurring in the vehicle body can be detected more reliably.

Road or surface conditions can also be determined by analyzing images or videos captured by camera sensor 249 . This makes it possible to anticipate the action of the lateral L force on the element 231 before actually driving on the road or surface causing the roll, and to take preventative measures.

Furthermore, road or road surface conditions can be determined not only by camera sensor 249 but also by navigation information obtained from car navigation device 250 . For example, if there is a road under construction in the traveling direction of the vehicle, or if there is a road with continuous unevenness or undulations, it is predicted that a force in the lateral direction L will act on the element 231 .

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of application examples of the present invention, and the technical scope of the present invention is not limited to the specific configurations of the above embodiments. do not have.

For example, the direction in which the receiving portion 231r opens when the element 231 is attached to the ring 232 may be the outer peripheral side (that is, the radially outer side) of the metal belt 23, or the inner peripheral side (the radially inner side). may be When the receiving portion 231r opens radially inward of the metal belt 23, the direction in which the lubricant is sprayed by the oil injector INJ3 in order to prevent the element 231 from falling off is different from the direction shown in FIG . On the contrary.

In the embodiment described above, the case where the transmission controller 201 implements the control unit has been described. However, the control unit may be implemented by, for example, multiple controllers.

In the above description , a drive source is provided and the engine 1 is adopted as the drive source. However , the drive source can be configured not only by an internal combustion engine but also by an electric motor (for example, a motor generator) or by a combination of an internal combustion engine and an electric motor.

1 engine 2 continuously variable transmission 21 primary pulley 22 secondary pulley 23 metal belt (belt)
231 element 231r receiver 232 ring 201 transmission controller (controller)
OSD oil supply device

Claims (6)

A continuously variable transmission mounted on a vehicle,
a primary pulley and a secondary pulley;
A belt stretched over the primary pulley and the secondary pulley,
a ring;
a plurality of elements bound by the ring, each having a receiving portion opening in the radial direction of the belt and receiving the ring in the receiving portion;
a belt having
a controller;
consists of
further comprising an oil supply device for blowing oil onto concentrated end play of the plurality of elements;
The oil supply device sprays oil onto the elements of the plurality of elements in a direction opposite to a direction in which the elements are displaced, and oil is applied to a portion opposite to a portion where the receiving portion opens. having an oil injector that sprays and/or
The controller controls the oil supply device when detecting a predetermined operating state, which is an operating state of the vehicle and an operating state in which there is a high possibility that the elements of the plurality of elements will come off, A control unit that executes oil supply control to increase the amount of oil blown to the end play concentration point compared to when the predetermined operating state is not detected,
A continuously variable transmission characterized by: A continuously variable transmission according to claim 1,
The control unit executes the oil supply control when detecting, as the predetermined operating state, an operating state in which end play of the plurality of elements concentrates.
A continuously variable transmission characterized by: A continuously variable transmission according to claim 1,
The control unit detects that the vehicle is in the predetermined driving state based on the accelerator opening and the vehicle speed.
A continuously variable transmission characterized by: A continuously variable transmission according to claim 3,
The control unit detects that the vehicle is in the predetermined driving state when the vehicle is on a slope.
A continuously variable transmission characterized by: A continuously variable transmission according to claim 1,
The control unit executes the oil supply control when detecting, as the predetermined operating state, an operating state in which a lateral force is applied to the element.
A continuously variable transmission characterized by: A primary pulley and a secondary pulley mounted on a vehicle, a belt that is stretched over the primary pulley and the secondary pulley, a ring, and a plurality of elements bound by the ring that are open in the radial direction of the belt. and a belt having a plurality of elements each having a receiving portion for receiving the ring in the receiving portion, the control method for a continuously variable transmission comprising:
The oil is blown to the end play concentration locations of the plurality of elements, and when the oil is blown to the end play concentration locations, the elements possessed by the plurality of elements are sprayed in a direction opposite to the direction in which the positional deviation of the elements occurs. at least one of spraying oil and spraying oil on a portion opposite to the portion where the receiving portion opens;
When a predetermined driving state, which is the driving state of the vehicle and is a driving state in which there is a high possibility that the elements of the plurality of elements will come off, is detected, the predetermined driving state is higher than when the predetermined driving state is not detected. Increase the amount of oil blown to the end play concentration point,
including,
A control method for a continuously variable transmission, characterized by:

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