JPH0756338B2 - Control method of continuously variable transmission for vehicle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a control method for a continuously variable transmission for a vehicle, and in particular,
The present invention relates to a control method for a continuously variable transmission that is suitable for use on a vehicle for traveling on rough terrain.

[Prior Art] Conventionally, as a control method of a continuously variable transmission for a vehicle, for example, a technology disclosed in Japanese Patent Application Laid-Open No. 57-161346 has been proposed.

As shown in the flow chart of FIG. 1, this technique reads the engine speed Ne, the vehicle speed V, and the gear ratio R after initializing the control system (step S1) (step S1).
2), Target gear ratio R for the read engine speed Ne
_M is set (step S3), it is determined whether the measured gear ratio R and the target gear ratio R _M match (step S4), and if R = R _M , the current The gear ratio R is maintained (step S5), and if they do not match, the magnitudes of the two are further compared (step S6).
When the measured gear ratio R is larger than the target gear ratio R _{M, the} transmission is gear-shifted to the TOP side so as to match the two (step S7), and the measured gear ratio R is set to the target gear ratio R _M. If it is smaller than the
The gear ratio is adjusted toward the W side (step S8), and the gear ratio R is adjusted to an appropriate value by continuously performing step S2 and subsequent steps.

[Problems to be Solved by the Invention] The present invention is intended to solve the following problems in the above-described conventional techniques.

In the above-mentioned conventional technique, the gear ratio of the continuously variable transmission is maintained at LOW when the engine is stopped, but when the engine is restarted by pushing in this state, the gear ratio is not appropriate. In addition, it is impossible to apply the force necessary for cranking to the engine,
Cannot restart quickly.

At the time of normal starting of the vehicle, generally, the clutch is held in a half-clutch state while increasing the engine rotation, and when the vehicle speed is sufficiently increased, the clutch is completely engaged, but in the initial stage, Even if the vehicle speed is not sufficient, it is assumed that the speed ratio is shifted to the TOP side by increasing the rotation of the engine, and sufficient driving force cannot be obtained at the time of starting.

When the correspondence between the rotational speed of the drive wheels and the actual vehicle speed is broken, for example, when the drive wheels are excessively rotated due to slip, the gear ratio is also increased due to the increase in the engine speed accompanying this.
It is assumed that when the shift is adjusted to the TOP side and the frictional force between the drive wheels and the traveling road surface is restored in this state, sufficient drive force cannot be applied to the drive wheels.

On the other hand, if the rotational speed of the drive wheels is reduced more than necessary due to locking, etc., the gear ratio is adjusted to the LOW side due to the decrease in engine speed, and the frictional force between the drive wheels and the road surface is reduced. When recovered, there is a risk that the engine will overspeed or excessive engine braking will occur.

[Means for Solving Problems] An object of the present invention is to provide a control method for a continuously variable transmission for a vehicle, which can effectively solve the above-mentioned problems in the conventional technique, and achieve the object. Therefore, a control method of a continuously variable transmission for a vehicle according to the present invention is, in particular, a control method of a continuously variable transmission provided between an engine mounted on a vehicle and a driving wheel, and an initial control, It consists of special control performed on condition that this initial control is determined to be unnecessary, and normal control performed on condition that this special control is determined to be unnecessary. It is characterized by including control of.

<Initial control> A) Detecting the operating state of each device mounted on the vehicle,
Fail-safe control performed when there is an abnormality in these operations.

B) On condition that each device is operating normally, it is judged whether the engine speed is below a set value, and if it is below the set value, shift of the continuously variable transmission is performed. Push-out control that adjusts the ratio to a value between TOP and LOW.

C) In B), on the condition that the engine speed is determined to be equal to or higher than the set value, it is determined whether or not the vehicle speed is equal to or higher than the set value, and when it is determined to be equal to or lower than the set value, Start control that adjusts the gear ratio of the continuously variable transmission to LOW.

<< Special control >> D) If the vehicle speed is judged to be equal to or higher than the set value in the above C), it is judged whether or not the driving wheels are in contact with the ground, and if it is judged that the driving wheels are not in contact with the ground. Jump control in which the speed ratio of the continuously variable transmission is maintained at a value immediately before the drive wheels are separated from the road surface or is adjusted to an optimum value set with this value as a reference.

E) On the condition that the drive wheel is in contact with the ground in D), it is determined whether the amount of change in the rotational speed of the drive wheel is within the set range, and it is determined that the change is outside the set range. In this case, the lock / slip control holds the gear ratio of the continuously variable transmission at a value immediately before the amount of change is out of the set range or adjusts it to an appropriate value.

F) When it is determined in E) that the amount of change in the rotational speed of the drive wheels is within the set range, it is determined that the vehicle clutch is disengaged, and it is determined that the clutch is disengaged. In addition, inertia traveling control that adjusts the gear ratio of the continuously variable transmission according to the elapsed time of power transmission interruption by this clutch and the amount of change in vehicle speed.

[Operation] According to the control method for the vehicle continuously variable transmission according to the present invention, the gear ratio of the continuously variable transmission is set to TOP when the engine is equal to or lower than the set rotational speed by the pushing control performed after the fail-safe control. Adjust the speed ratio between LOW and LOW to maintain the optimum gear ratio for pushing, and the subsequent start control makes it easy to start the gear ratio even if the engine speed is increased during start. If the drive wheels are kept at LOW and the vehicle shifts from the start to normal running and the driving wheels are separated from the road surface due to a vehicle jump or the like, and the relative relationship between the engine speed and the actual vehicle speed is lost, a jump following the start control is performed. By control
Adjust the gear ratio assuming the case where the driving theory is re-grounded,
Facilitates re-driving or suppresses engine overspeed,
In addition, during normal traveling, when the drive wheels are over-rotated due to slip or stopped due to lock or excessive deceleration,
The lock / slip control provides an appropriate driving force when the friction between the drive wheels and the road surface is restored,
Alternatively, adjust the engine to a value that prevents over-rotation, and further disengage the clutch during normal driving to cut off the power transmission to the drive wheels, and when the relationship between the actual vehicle speed and the engine speed collapses, inertia By adjusting the gear ratio according to the amount of change in the power cutoff elapsed time and the actual vehicle speed by the travel control, the driving force applied to the drive wheels at the time of re-driving can be achieved regardless of the change in the engine speed during power cutoff. Appropriate, or to prevent engine overspeed.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 2 to 24.

First, a continuously variable transmission for a vehicle to which this embodiment is applied will be described with reference to FIGS. 2 to 13.

This continuously variable transmission is mounted on a motorcycle as a vehicle. In FIGS. 2 and 3, the power of the engine E of the motorcycle is derived from the crankshaft 1 of the chain type primary reduction gear 2, Hydrostatic type continuously variable transmission (hereinafter abbreviated as continuously variable transmission) T, and chain type secondary speed reducer 3
Is transmitted to a drive wheel Wr (or a rear wheel when applied to a motorcycle) described later.

The continuously variable transmission T includes a constant displacement swash plate hydraulic pump (hereinafter abbreviated as hydraulic pump) P and a variable displacement swash plate hydraulic motor (hereinafter abbreviated as hydraulic motor) M. The crankcase 4 that supports the crankshaft 1 is housed inside as a casing.

The hydraulic pump P is a cup-shaped input member 5 in which the output sprocket 2a of the primary reduction gear device 2 is connected with three rivets 14, and a relative rotation via a needle bearing 6 on the inner peripheral wall of the input member 5. A freely-fitting pump cylinder 7 and a plurality of odd-numbered cylinder holes 8 in an annular array formed so as to surround the center of rotation of the pump cylinder 7.
It is composed of a pump plunger 9 that is slidably mounted inside, and a pump swash plate 10 that abuts the outer ends of these pump plungers 9.

The pump swash plate 10 is held so as to be tiltable within a range of a predetermined angle about a virtual trunnion axis O ₁ orthogonal to the axis of the pump cylinder 7, and its back surface (that is, the pump plungers 9 ... On the surface opposite to the contacting side), it is rotatably supported by the inner end wall of the input member 5 via a thrust roller bearing 11.

The surface of the input member 5 that supports the pump swash plate 10 is, as shown in FIG. 2, formed so as to be inclined by a predetermined angle with respect to the axis of the pump cylinder 7. When the input member 5 rotates, the pump swash plate
10 is reciprocally tilted to reciprocate the pump plungers 9 ... Abutting on the pump swash plate 10 along the axial direction of the pump cylinder 7 to suck and discharge hydraulic oil in each cylinder hole 8. Is to be repeated.

Here, in order to improve the followability of the pump plungers 9 ... With respect to the pump swash plate 10 as described above, the direction in which the pump plungers 9 ... You may make it interpose the spring which urges | biases.

The back surface (the outer end surface located on the right side in FIGS. 2 and 3) of the input member 5 is supported by a support cylinder 13 via a thrust roller bearing 12.

On the other hand, the hydraulic motor M is formed coaxially with the pump cylinder 7 on the left side thereof (on the left side in FIGS. 2 and 3) and the motor cylinder 17 so as to surround the rotation center thereof. 19 which are slidably mounted in a plurality of odd-numbered cylinder holes 18 ...
, And a motor swash plate 20 that abuts the outer ends of these motor plungers 19 and a back surface of the motor swash plate 20 (that is, a surface opposite to the side where the motor plungers 19 abut). It is composed of a swash plate holder 22 supported via a thrust roller bearing 21, and a swash plate anchor 23 supporting the swash plate holder 22.

The motor swash plate 20 can be tilted between an upright position that is perpendicular to the axis of the motor cylinder 17 and a maximum tilt position that tilts at a certain angle. Motor plunger 19 with rotation of 17
.. are reciprocated along the axis of the motor cylinder 17, so that suction and discharge of hydraulic oil are repeated in the cylinder holes 18.

In order to improve the followability of each of the motor plungers 19 to the motor swash plate 20, like the hydraulic pump P, a spring may be interposed between the motor plungers 19 and the motor cylinders 17. Is.

On the other hand, the pump cylinder 7 and the motor cylinder 17
Of the cylinder block B are connected to each other at their opposite ends to form an integral cylinder block B, and the output shaft 25 is inserted along the axis of the cylinder block B.

A flange 25a is integrally formed on the outer periphery of the output shaft 25, the outer end of the motor cylinder 17 is abutted against the flange 25a, and the pump cylinder 7 is fitted to the output shaft 25 by a spline. When the circlip 26 locked to the output shaft 25 is brought into contact with the outer end of the pump cylinder 7, the cylinder block B is attached to the output shaft 25 in the longitudinal direction and circumferential direction. In any of the directions, the movement is fixed while the relative movement is restricted.

The output shaft 25 also penetrates the input member 5 and rotatably supports the input member 5 via a needle bearing 27.

Further, the support cylinder 13 is fitted on the outer periphery of the right end portion (right side portion in FIGS. 2 and 3) of the output shaft 25, and the support cylinder 13 is attached to the output shaft 25 by a key 28. The rotation relative to and is constrained, and is fixed by a nut 30 screwed to the output shaft 25, and the support cylinder 13 is rotatably supported by the crankcase 4 via a roller bearing 31. Thus, the right end of the output shaft 25 is rotatably supported by the crankcase 4.

On the other hand, the output shaft 25 penetrates through the central portions of the motor swash plate 20, the swash plate holder 22, and the swash plate anchor 23, and at the left end thereof, the back surface of the swash plate anchor 23 is thrust roller bearing.
A support cylinder 33 supported via 32 is spline-fitted, and this support cylinder 33 is used as the input sprocket 3a of the secondary speed reducer 3.
Along with the nut 34, the support cylinder 33 is attached to the crankcase 4 via the roller bearing 35, so that the left end of the output shaft 25 is attached to the crankcase 4.
It is rotatably supported on.

Further, at a position of the output shaft 25 facing the pump swash plate 10, a hemispherical alignment body 36 slidably engaged with the inner peripheral surface of the pump swash plate 10 so as to be tiltable in all directions. The spline is fitted. The aligning body 36 receives the elastic force of a plurality of disc springs 38 interposed between it and the output shaft 25, and the pump swash plate.
The 10 is pressed against the thrust roller bearing 11, which constantly gives the pump swash plate 10 an aligning action.

On the other hand, at a position of the output shaft 25 facing the motor swash plate 20, a hemispherical centering body 37 slidably engaged with the inner peripheral surface of the motor swash plate 20 so as to be tiltable in all directions. The spline is fitted. The alignment body 37 receives the elastic force of a plurality of disc springs 39 interposed between the alignment plate 37 and the output shaft 25, and the motor swash plate.
20 is pressed toward the thrust roller bearing 21, whereby the motor swash plate 20 is always provided with the centering action.

The swash plates 10 and 20 have their centering action strengthened, and prevent slipping in the rotational direction between the pump swash plate 10 and the pump plunger 9 group, and between the motor swash plate 20 and the motor plunger 19 group. In order to do so, the corresponding spherical end of the plunger 9/19
Spherical recesses 10a and 20a with which 9a and 19a are engaged are formed, respectively.

A hydraulic closed circuit is formed between the hydraulic pump P and the hydraulic motor M described above as follows.

In the cylinder block B, an annular inner oil passage 40 and an outer oil passage 40 are concentrically arranged around the output shaft 25 between the group of cylinder holes 8 of the pump cylinder 7 and the group of cylinder holes 18 of the motor cylinder 17. The passage 41, the annular partition wall between the two oil passages 40, 41 and the outer peripheral wall of the outer oil passage 41 are radially penetrated, and the same number of first valve holes 42 ... The valve hole 43, the adjacent cylinder hole 8 and the first valve hole
A large number of pump ports a, which communicate with each other 42, and a large number of motor ports b, which mutually communicate with the adjacent cylinder holes 18 and second valve holes 43, are provided. At that time, the inner oil passage 40 is connected to the cylinder block B and the output shaft 25.
The outer oil passage 41 is formed between the outer circumferential surface of the cylinder block B and the outer circumferential surface of the sleeve 44 which is fitted and welded to the outer circumference of the cylinder block B, and the inner oil passage 40 is formed. The low pressure oil passage is formed, and the outer oil passage 41 is formed as the high pressure oil passage.

A first distribution valve 45 is slidably mounted in each of the first valve holes 42, and a second distribution valve 46 is slidably mounted in the second valve hole 43.

In this embodiment, a distribution mechanism is composed of these distribution valves.

Each of the first distribution valves 45 is formed in a spool type as shown in FIG. 9, and when it occupies the radially outer position of the first valve hole 42 in FIG. While communicating with the oil passage 41 and not communicating with the inner oil passage 40,
The corresponding cylinder hole 8 communicates only with the outer oil passage 41, and the first
When the valve hole 42 is located radially inward, the corresponding pump port a is communicated with the inner oil passage 40 and is not communicated with the outer oil passage 41, and the corresponding cylinder hole 8 is communicated only with the inner oil passage 40. When the central position of the first valve hole 42 is occupied, the pump port a and both oil passages 40 and 41 are cut off.

In order to give such an operation to each first distribution valve 45, the second
As shown in FIGS. 3 and 4, a first eccentric ring 47 surrounds the first distribution valve 45 ... Engages with the outer ends of the group, and the follower is arranged concentrically with the eccentric ring 47. Wheel 47 'is the first
Engagement with engagement grooves 45a formed at the inner ends of the distribution valves 45. The follower wheel 47 'and the first distribution valve 45 ...
The rotation of each first distribution valve 45 ... Is prevented by the engagement with.

On the other hand, the follower wheel 47 'is made of steel wire and
The follower wheels 47 'are arranged so as to spring the distribution valves 45 ... In a direction of contacting the inner surface of the first eccentric wheel 47.
In order to absorb the manufacturing error of its diameter, one cut is provided in a part in the circumferential direction.

The first eccentric wheel 47 is rotatably supported by a first control ring 51 connected to the input member 5 via a ball bearing 48, and usually, as shown in FIG. 4, the pump swash plate.
It is arranged at a first eccentric position e which is eccentric by a constant distance ε ₁ from the center of the output shaft 25 along the 10 virtual trunnion axis O ₁ . Therefore, when the relative rotation occurs between the input member 5 and the pump cylinder 7, each first distribution valve 45 ... Strokes in the valve hole 42 at a distance twice the eccentric amount ε ₁ of the first eccentric ring 47. It can be reciprocated between the outer position and the inner position.

2 to 4, the first control ring 51 has a rivet 14 for connecting the sprocket 2a to the input member 5.
One of them is pivotally connected to the input member 5 via a pivot 14a formed by extending one end thereof. That is,
The first control ring 51 swings around the pivot 14a between a clutch-on position g as shown in FIG. 4 and a clutch-off position h as shown in FIG. 4A. At the former clutch-on position g, the first eccentric wheel 47 is
It is controlled to a first eccentric position e which is eccentric from the center of the output shaft 25 along the virtual trunnion axis O ₁ by a distance ε ₁ , and in the latter clutch-off position h, the first eccentric wheel 47 is shown in FIG. 4A. Thus, the second eccentric position f is eccentric from the center of the output shaft 25 along the perpendicular L of the virtual trunnion axis O _{1 by} the distance ε ₁ .

In order to regulate the swing range of the first control ring 51 as described above,
As shown in FIGS. 6 and 7, a guide pin 52 fixed to the control ring 51 and projecting from the inner peripheral surface thereof is formed on the outer periphery of the input member 5 in a predetermined length along the circumferential direction thereof. The guide groove 53 is swingably engaged.

Between the first control ring 51 and the input member 5, as shown in FIG. 5, a leaf spring 54 for constantly elastically pushing the first control ring 51 toward the clutch-on position g is interposed. There is. This leaf spring 54 has its center portion riveted to the inner surface of the first control ring 51.
It is fixed at 55 and both ends thereof are brought into contact with the outer surface of the input member 5, whereby the first control ring is
It is designed to repel 51 in the direction described above.

As shown in FIGS. 3 and 5 to 7, a roller 56 is attached to the guide pin 52, and a push arm protruding from one side of the operating ring 57 is attached to the roller 56. 58 is engaged.

As shown in FIG. 3, the operating ring 57 is slidably and rotatably fitted to the outer peripheral surface of the input member 5 on the side opposite to the first control ring 51 with the output sprocket 2a interposed therebetween, and the push arm 58 thereof. Penetrates through a through hole 59 projecting from the output sprocket 2a and faces the guide pin 52 in the circumferential direction of the first control ring 51.

As shown in FIG. 7, the push arm 58 is provided with a recess 60 with which the roller 56 is engaged when the first control ring 51 is located at the clutch-on position g.
Further, as shown in the figure, the push arm 58 is formed in a mountain shape so as to gradually widen toward the operating ring 57, and one slope 58a forming the mountain shape is continuous with the recess 60, The other slope 58b is slidably engaged with a guide slope 59a formed on the inner wall of the through hole 59.

A release ring 62 is rotatably attached to the outer periphery of the operating ring 57 via a release bearing 61, as shown in FIGS. 2, 3, and 7.
A push protrusion 64a of an annular clutch lever 64, which is swingably supported by the crankcase 4 via a shaft 63 and surrounds the input member 5, is brought into contact therewith.

At the swinging end of the clutch lever 64, as shown in FIGS.
As shown in the figure, the inner lever 66a of the bell crank 66, which is swingably supported by the shaft 65 on the crankcase 4, is
The clutch lever 64 is in contact with the release ring 62 so that it can be pushed toward the release ring 62 side, and a return spring 67 that elastically springs the clutch lever 64 to the side opposite to the release ring 62 is connected.

As shown in FIG. 8, the bell crank 66 has the above-mentioned inner lever 66a arranged in the crank case 4 and an outer lever 66b arranged outside the case 4,
A clutch lever 141, which will be described later, operated by an operator is connected to the outer lever 66b via a wire 68.

In the present embodiment, the above-described first distribution valve 45, first eccentric ring 47, first control ring 51, actuation ring 57, push arm 58, release ring 6 are provided.
2, the clutch lever 64, and the bell crank 66 constitute a clutch mechanism.

Each of the second distribution valves 46 is also a first distribution valve as shown in FIG.
When it is formed in the same spool type as 45 and occupies the radially outer position of the second valve hole 43, the corresponding motor port b is communicated with the outer oil passage 41 and is not communicated with the inner oil passage 40, When the corresponding cylinder hole 18 is communicated only with the outer oil passage 41, and when it occupies the radially inner position of the second valve hole 43, the corresponding motor port b is communicated with the inner oil passage 40 and is not communicated with the outer oil passage 41. Then, when the corresponding cylinder hole 18 is communicated only with the inner oil passage 40, and when the center position between the above two positions is occupied, the corresponding motor port 6 is made incapable of communicating with both the inner and outer oil passages 40, 41. .

In order to give such an operation to each second distribution valve 46, the second
As shown in FIGS. 3, 3 and 10, a second eccentric wheel 49 surrounds the second distribution valves 46 ... Engages with their outer ends and is concentric with the second eccentric wheel 49. The follower wheels 49 'are disposed inside the second distribution valve 46 ... Group and engaged with the engagement grooves 46a formed at their inner ends.

The rotation of each second distribution valve 46 is blocked by the engagement between each second distribution valve 46 ... And the follower wheel 49 '.

The follower wheel 49 'is formed of steel wire and is arranged so as to elastically push the second distribution valves 46 ... In the engagement direction with the second eccentric wheel 49. This follower wheel 49 'is also preferably provided with one cut, like the follower wheel 47'.

As shown in FIG. 10, the second eccentric wheel 49 is a motor swash plate.
Output shaft along the 20 tilt axes or trunnion axis O _2.
An eccentric position l eccentric from the center of 25 by a constant distance ε ₂ ,
It is controlled to a concentric position m which is concentric with the output shaft 25.

Thus, when the motor cylinder 17 rotates when the second eccentric wheel 49 occupies the first eccentric position l, each second distribution valve 46 is rotated.
Is reciprocated between the outer position and the inner position with a stroke that is twice the eccentric amount ε ₂ of the second eccentric wheel 49 in the valve hole 43, and when the concentric position m is occupied, the motor is Regardless of the rotation of the cylinder 17, all the second distribution valves 49 ... Are retained in the central position.

Referring again to FIG. 3, a pair of upper and lower trunnion shafts 70, 70 ′ aligned on the trunnion axis O ₂ of the motor swash plate 20 are integrally provided at both ends of the swash plate holder 22. ′ Is rotatably supported on both side walls of a cylindrical motor housing 72 integral with the crankcase 4 via roller bearings 71, 71 ′. In other words, the trunnion axis O ₂ is defined by the trunnion axes 70 and 70 '. The motor housing 72 is a motor cylinder.
17 is also rotatably supported via a needle bearing 73.

Further, as shown in FIGS. 2, 11 and 12, a tilt angle control mechanism 80 for controlling the tilt angle of the motor swash plate 20 is continuously provided on the one trunnion shaft 70.

The inclination angle control mechanism 80 is fixed to the crankcase 4 with a bolt 79, a sector gear 81 rotatably supported by the trunnion shaft 70, a damper 82 elastically connecting the sector gear 81 to the trunnion shaft 70. The bracket plate 83 is supported via bearings 84, 84 'and is composed of a worm gear 85 that meshes with the sector gear 81, and a forward and reverse reversible DC electric motor 86 in which a drive shaft 86a is connected to the worm gear 85. The electric motor 86 is mounted on the crankcase 4 by fixing the stator 86b to the crankcase 4 at a proper position.

In such a configuration, the sector gear 81 and the worm gear 85 reduce the rotation of the drive shaft 86a to reduce the rotation of the trunnion shaft 70.
However, the speed reducer R is configured to be in a locked state when a reverse load is applied from the trunnion shaft 70.

The damper 82 has a fan-shaped buffer chamber 87 centered on the trunnion shaft 70, a damper main body 89 fixed to the trunnion shaft 70 with a bolt 88, and a pair of rubber buffers loaded in the buffer chamber 87. Both the cushioning members 90 and 90 'are provided.
A conductive piece 91 protruding from one side surface of the sector gear 81 is inserted between 90 '.

In such a tilt angle control mechanism 80, the electric motor 86
Rotation of the worm gear 85
Is transmitted from the sector gear 81 to the sector gear 81 after being decelerated.
The motor swash plate 20 attached to the trunnion shaft 70 is transmitted to the trunnion shaft 70 via the cushioning member 90, the cushioning member 90 or 90 ', and the damper body 89 to rotate the motor swash plate 20 in the standing direction or the tilting direction.

At that time, if a pulsation occurs in the thrust load applied to the motor swash plate 20 from the motor plungers 19 ... Group, the pulsation is absorbed by the elastic deformation of the cushioning members 90, 90 ', and the load on the worm gear 85 and the sector gear 81 is thereby absorbed. Is reduced.

Further, when the electric motor 86 is stopped and the motor swash plate 20 is held at an arbitrary angle, the motor swash plate 20 causes the motor plunger 19 ...
Even if a moment in the standing or tilting direction is received from the group and that moment is transmitted to the sector gear 81 via the trunnion shaft 70, the worm gear 85 cannot be driven by the sector gear 81, so both gears 81 and 85 are locked. The rotation of the trunnion shaft 70 is restricted, and the motor swash plate 20 is reliably held at the position at that time.

Then, in order to restrict the standing position and the tilted position of the motor swash plate 20 by the electric motor 86, the sector gear 81 is provided with an arcuate restriction groove 92 concentric therewith, and is freely slidable in the restriction groove 92. A restriction collar 93 that engages with is fixed to the bracket plate 83 with a bolt 94.

Further, in FIGS. 3 and 10, the second eccentric wheel is shown.
49 is rotatably supported by the second control ring 95 via the bearing 50. The second control ring 95 has a pair of ears 96, 96 'on both sides in the direction of the trunnion axis O ₂ and one ear 96
Has a U-shaped guide groove 97 extending in the direction of the trunnion axis O _2.
The guide pin 98 fixed to the crankcase 4 is slidably engaged with the guide groove 97. A second guide pin 99 is fixedly mounted on the other ear 96 ', and the guide pin 99 is formed on a supporting member 101 projecting from the inner wall of the crankcase 4 and the trunnion axis O _{2 is formed.} It is slidably engaged with a U-shaped guide groove 100 extending in the direction.

With such a configuration, the second control ring 95 can be displaced along the trunnion axis O ₂ , and the second eccentric wheel 49 can be controlled to the eccentric position 1 and the concentric position m by this displacement. In addition, the second eccentric ring 4 is moved by the return spring 102 formed of a leaf spring interposed between the guide pin 99 integrated with the second control ring 95 and the crankcase 4.
Along with 9, it is constantly repulsed toward the eccentric position l.

Further, a cam hole 103 is formed in the other ear portion 96 ',
A control lever 104 fixed to the trunnion shaft 70 'is inserted.

The cam hole 103 has a control lever whose inner surface on the return spring 102 side is swingably attached to the crankcase 4.
The control lever 104 is formed as a cam surface 103a with which the sliding contact is made, and can be moved substantially along the circumferential direction of the second control ring 95.
In cooperation with 104, the second control ring 95 is displaced against the force of the return spring 102 to displace the second eccentric ring 49 within the range between the eccentric position 1 and the concentric position m. It can be done.

In this embodiment, the second distribution valve 46, the second eccentric wheel 49, the second
Control ring 95, guide pin 98, second guide pin 99, support member 10
1, the return spring 102, the cam hole 103, and the control lever 104 form a flow rate adjusting mechanism.

Then, when the second eccentric wheel 49 reaches the concentric position m, all the second distribution valves 46 ... Are closed as shown in FIG. 10A, and the outer (high pressure) oil passage 41 and the inner (bottom pressure) oil passage 41. All of the oil passages 40 are shut off from the hydraulic motor M. As a result, the volume of the low-pressure circuit communicating with the hydraulic pump P is reduced by the volume of the hydraulic motor M, so that even if the operating oil contains some air bubbles, the amount of compression of the operating oil by the hydraulic pump P is extremely small, and The relative rotation between the input member 5 and the output shaft 25 is minimized, and the transmission efficiency is improved. Further, at the intermediate position reaching the concentric position, the opening degree of each pump port b of the hydraulic motor M can be adjusted to adjust the flow rate of the hydraulic oil from these pump ports b.

The displacement of the second eccentric wheel 49 to the concentric position m is determined by the cam hole 103.
By the action of the cam surface 103a, the operation is continuously performed in conjunction with the operation of the control lever 104, and the valve is closed, that is, the concentric position m described above is reached. Therefore, the improvement of the transmission efficiency starts gradually before reaching the valve closed state, so that the shift shock at the time of the valve closing is prevented.

On the other hand, the clutch mechanism, the tilt angle control mechanism 80, and
The flow rate adjusting mechanism has a control means U for controlling these operations.
Are lined up.

The control means U will be described below in relation to the hydraulic circuit shown in FIG.

First, the hydraulic circuit will be described.

In the drawing, reference character E is an engine, F is an oil pump driven by the engine E, C is a clutch mechanism, Q is a flow rate adjusting mechanism, Wr is a drive wheel rotationally driven by the output shaft 25, and Wf is a driven wheel. , Respectively, and a hydraulic closed circuit G is formed between the hydraulic pump P and the hydraulic motor M.

This hydraulic closed circuit G is the outside oil passage forming a high pressure oil passage.
41 and the inside oil passage 40 forming a low pressure oil passage.

The oil pump F is connected to the inner oil passage 40 and the outer oil passage 41 through the replenishment oil passage 120 and the check valve 121, and the working oil pumped up from the oil tank 122 is the replenishment oil passage. It is designed to be supplied via 120 and a check valve 121. Further, a relief valve for adjusting the pressure of the hydraulic oil to be supplied is provided in the middle of the supply oil passage 120.
123 are provided.

The clutch mechanism C is a first distribution valve as a clutch valve.
The actuator 125 is provided with a clutch sensor 124 for detecting the operating position of 45, and the flow rate adjusting mechanism Q includes the operating position of the second eccentric wheel 49, that is, the second
The actuator 127 is provided with a flow rate sensor 126 for detecting the operating position of the control ring 95, and the tilt angle control mechanism 80 further includes the tilt position of the electric motor 86 as an actuator and the motor swash plate 20, that is, the gear shift. And a ratio sensor 128 for detecting the position.

Then, the control means U electrically drives the clutch mechanism C, the flow rate adjusting mechanism Q, the actuators 125 and 127 and the electric motor 86 that configure the tilt angle control mechanism 80, the clutch sensor 124, the flow rate sensor 126, and the ratio sensor 128. Of the engine E and the engine speed Ne
The rotational speed sensor S _a for detecting the engine speed, the throttle sensor S _b for detecting the throttle opening of the engine E, the vehicle speed sensor S _c for detecting the rotational speed of the drive wheel Wr, and the operating states of the braking mechanism such as the brake lever of the vehicle. A brake sensor S _d for detecting and a vehicle speed sensor S _e for detecting the rotation speed of the driven wheels W _f are connected to each other, and information from these sensors is constantly input.

Next, the operation of the hydrostatic continuously variable transmission having the above-described configuration will be described.

First, the operation of each component in a normal gear shift operation will be described.

In the above-mentioned configuration, the first control ring 51 occupies the clutch-on position g so that the first eccentric wheel 47 is moved to the first eccentric position e.
On the other hand, when the second eccentric wheel 49 occupies the first eccentric position e, on the other hand, from the primary reduction gear transmission 2 to the input member 5 of the hydraulic pump P.
When the pump is rotated, suction and discharge strokes are alternately given to the pump plungers 9 by the pump swash plate 10. The suction stroke region S and the discharge stroke region D of this hydraulic pump P are shown in FIG.

The first distribution valve 45 in the intake stroke region S is moved inward by the cooperation of the first eccentric wheel 47 and the follower wheel 47 ', and the first distribution valve 45 in the discharge stroke region D is the first The eccentric wheel 47 and the follower wheel 47 'cooperate to move the wheel to the outer position. Therefore, each pump plunger 9 sucks the working oil from the inner oil passage 40 into the cylinder hole 8 in the suction stroke, and pumps the working oil from the cylinder hole 8 to the outer oil passage 41 in the discharge stroke.

The high-pressure hydraulic oil sent to the outer oil passage 41 is moved to the motor port b existing in the expansion stroke region Ex (see FIG. 10) of the hydraulic motor M, and is moved to the outer position by the second eccentric wheel 49 and the follower wheel 49 '. Delivered via a controlled second distribution valve 46. on the other hand,
Motor port b in contraction stroke region Sh (see Fig. 10)
The hydraulic oil discharged from the second eccentric wheel 49 and the follower wheel 4
It is guided to the inner oil passage 40 via a second distribution valve 46 which is controlled inward by 9 '.

During this time, the reaction torque that the pump cylinder 7 receives from the pump swash plate 10 via the pump plunger 9 in the discharge stroke,
The cylinder block B is rotated by the sum of the reaction torque that the motor cylinder 17 receives from the motor swash plate 20 via the motor plunger 19 in the expansion stroke, and the rotation torque is transmitted from the output shaft 25 to the secondary reduction gear 3. .

In this case, the gear ratio R of the output shaft 25 with respect to the input member 5 is given by the following equation.

Therefore, if the capacity of the hydraulic motor M is changed from zero to a certain value, the gear ratio can be changed from 1 to a certain required value.

By the way, since the capacity of the hydraulic motor M is determined by the stroke of the motor plunger 19, the gear ratio is continuously controlled from 1 to a certain value by tilting the motor swash plate 20 from the upright position to a certain tilt position. be able to.

During such an operation, by operating the clutch lever 141, which will be described later, the clutch lever 64 is swung toward the release ring 62 side against the force of the return spring 67 via the wire 68 and the bell crank 66. The pressing force applied to the ring 62 acts on the actuating ring 57 via the release bearing 61 and slides it to the left as shown by the arrow 74 in FIG. 7 to move the pushing arm 58 into the through hole of the output sprocket 2a. Push it deep into 59. Then, due to the pressing action of the guide slope 59a of the through hole 59 against the slope 58b of the push arm 58 and the pressing action of the slope 58a of the push arm 58 against the roller 56, even if the axial displacement 74 of the operating ring 57 is small,
A large circumferential displacement 75 (see FIG. 7) can be applied to 56, which causes the first control ring 51 to swing from the clutch on position g to the clutch off position h against the force of the leaf spring 54.

As a result, the first eccentric wheel 47 moves from the first eccentric position e to the second eccentric position f, and as shown in FIG.
In each of the regions S and D of the intake stroke and the discharge stroke, the first distribution valve 45 causes the portion of the pump port a ...
Since the other half is connected to the outer oil passage 41, the hydraulic pump P is short-circuited, so that the high-pressure hydraulic oil discharged from the pump port a in the discharge stroke region D of the hydraulic pump P is immediately sucked. The oil is sucked into the pump port a in the stroke region S, the transfer of hydraulic oil between the hydraulic pump P and the hydraulic motor M is stopped, and the transmission of power from the hydraulic pump P to the hydraulic motor M is cut off, resulting in a clutch-off state.

Pump swash plate during operation of hydraulic pump P and hydraulic motor M
10 is a thrust load from the pump plunger 9 group, and the motor swash plate 20 is a thrust load from the motor plunger 19 group, but the thrust load received by the pump swash plate 10 is the thrust roller bearing 11, the input member 5, and the thrust member. The thrust load that is supported by the output shaft 25 through the roller bearing 12, the support cylinder 13 and the nut 30 and that the motor swash plate 20 receives is the thrust roller bearing 21, the swash plate holder 22,
Swash plate anchor 23, thrust roller bearing 32, support tube 3
3, also supported on the output shaft 25 via the input sprocket 3a and the nut 34. Therefore, the thrust load only causes tensile stress in the output shaft 25 and does not act on the crankcase 4 supporting the output shaft 25 at all.

Then, the continuously variable transmission T configured as described above is mounted on a motorcycle as shown in FIGS. 14 and 15.

That is, the motorcycle includes a body frame 130, an engine E supported by the body frame 130, and a continuously variable transmission T arranged at a rear stage of the engine E.

The continuously variable transmission T in this case is a hydraulic type,
As shown in the figure, the output shaft 25 is arranged in the left-right direction of the vehicle body so as to be parallel to the crankshaft 1 of the engine E.

Reference symbol Wf denotes a driven wheel, and Wr denotes a driving wheel to which driving force is transmitted from the engine E. A fuel tank 131 is provided above the front of the vehicle body frame 130, and a seat rail 130 at the rear.
A seat 132 is fixed on a.

The driven wheel Wf is rotatably supported by a lower end of a front fork 134 attached to a head pipe 133 in the front part of the vehicle body frame 130, and a handle 135 attached to the front fork 134 is arranged above the head pipe 133. It is set up.

On the other hand, as shown in FIG. 15, the drive wheel Wr is mounted on a body frame 130 such that a swing arm 137 mounted so as to swing while receiving a reaction force of a cushion unit 136.
It is rotatably supported at the end on the rocking side of the vehicle and, as shown in FIG. 14, is connected to the output shaft 25 of the continuously variable transmission T by the secondary reduction gear 3 arranged on the left side of the vehicle body. There is.

On the other hand, reference numeral 138 is an air cleaner, 139 is an exhaust pipe, 140 is an accelerator grip, and 141 is a clutch lever. Also, 1
Both 42 and 143 are brake pedals.

In this case, the driving wheel Wr can be braked by operating either the left or right brake pedal 142/143.

Next, the control method of the present embodiment applied to the continuously variable transmission T having the above-described configuration will be described based on the flowchart of FIG.

The control method of the present embodiment includes an initial control I and this initial control I
Special control that is performed on condition that is determined to be unnecessary
II and a normal control III which is performed on condition that this special control II is judged to be unnecessary.
And special control II is step S1 for initializing the control system.
Then, following step S2 of reading each sensor value after step S1, the following procedure is performed.

<< Initial control I >> (Step S3) When the operating states of the devices mounted on the vehicle are detected, and if there is an abnormality in these operations, the process proceeds to Step S4, and if the operation of all devices is normal Then, the process proceeds to step S5.

(Step S4) For example, fail-safe control such as adjusting the gear ratio to the TOP side is performed, and the process returns to step S2.

(Step S5) It is determined whether the engine speed Ne is less than or equal to a set value. If it is determined to be less than or equal to the set value, the process proceeds to step S6, and if it is determined to be greater than or equal to the set value, the step is performed. Move to S7.

(Step S6) Adjust the continuously variable transmission T to a gear ratio between TOP and LOW and return to step S2 (pushing control).

(Step S7) It is determined whether the vehicle speed V is equal to or higher than the set value, and if it is determined to be equal to or lower than the set value, the process proceeds to step S8, and if it is determined to be equal to or higher than the set value, step S9 of the special control II. Move to.

(Step S8) After adjusting the gear ratio R of the continuously variable transmission T to LOW, the process returns to step S2 (start control).

<< Special control II >> (step S9) Whether or not the drive wheel Wr is in contact with the ground is determined. If it is determined that the drive wheel Wr is not in contact with the ground, the process proceeds to step S10,
If it is determined to be grounded, the process proceeds to step S11.

(Step S10) The gear ratio R of the continuously variable transmission T is maintained at a value immediately before the drive wheel Wr is separated from the road surface, or adjusted to an optimum value set with this value as a reference, and then the process returns to step S2 ( Jump control).

(Step S11) It is determined whether or not the amount of change in the rotation speed V _RR of the drive wheel Wr is within the set range. If it is determined that the change is outside the set range, the process proceeds to step S12, and the set range is determined. If so, the process proceeds to step S13.

(Step S12) The gear ratio R of the continuously variable transmission T is maintained at a value immediately before the amount of change out of the set range, or adjusted to an appropriate value, and then the process returns to step S2 (lock / slip control). ).

(Step S13) Whether the clutch mechanism C of the vehicle is engaged or disengaged is determined, and when it is determined that the clutch mechanism C is disengaged and the power transmission to the drive wheels Wr is interrupted, the process proceeds to step S14 and the clutch mechanism C is performed. When it is determined that is connected and the driving force is transmitted to the driving wheels Wr, the process proceeds to step S15 of normal control III.

(Step S14) The gear ratio R of the continuously variable transmission T is adjusted according to the elapsed time ΔT of interruption of power transmission to the drive wheels Wr by the clutch mechanism C and the amount of change in the vehicle speed V, and then the process returns to step S2 (inertial running control).

<< Normal Control >> (Step S15) After adjusting the gear ratio R of the continuously variable transmission T based on various control factors such as the throttle opening θ, the engine speed Ne, and the vehicle speed V, the process returns to step S2.

Next, details of each control will be described.

In the following description, the steps before and after the target control will be appropriately described together.

First, the pushing control (step S6) will be described with reference to FIG.

This pushing control is performed by the engine E in step S2.
Revolution speed sensor Sa, throttle sensor Sb, vehicle speed sensor S
c, and the ratio sensor 128, the rotational speed Ne of the engine E, the throttle opening θ, the vehicle speed V, the gear ratio R are read respectively, and based on these, the operation of each device is normal, and the engine E Number of revolutions Ne is set number of revolutions N _e1
The following procedure is performed on condition that it is determined to be smaller.

The set rotational speed N _e1 is, for example, an upper limit rotational speed at which the engine E can be considered to be stopped, and is set to a value that is a small percentage of the idling rotational speed.

(Step S61) It is judged whether or not the read actual gear ratio R is larger than the gear ratio R _T set on the TOP side (whether it is on the LOW side or the TOP side of the gear ratio R _T ). If it is determined to be on the TOP side, the process proceeds to step S62, and if it is determined to be on the LOW side, the process proceeds to step S63.

(Step S62) The continuously variable transmission T is shifted to the LOW side, and the process returns to step S61.

(Step S63) It is determined whether or not the gear ratio R is smaller than the gear ratio R _L set to the LOW side (whether it is on the TOP side or the LOW side of the gear ratio R _L ), and if it is larger (LOW Step S)
If it is smaller (if it is on the TOP side), the process proceeds to step S65.

(Step S64) The continuously variable transmission T is shifted to the TOP side, and the process returns to step S63.

(Step S65) The shifting operation of the continuously variable transmission T is stopped, the gear ratio R is maintained, and the process returns to step S2.

By the control from step S61 to step S64 described above,
When it is considered that the engine E has stopped, the gear ratio R of the continuously variable transmission T is adjusted between LOW and TOP, and the optimum crankshaft 1 of the engine E required for cranking is adjusted during pushing. It is held at a value that can give torque.

The optimum gear ratio R for pushing can be, for example, a value corresponding to the second speed or the third speed in a fifth speed multi-stage transmission.

Next, starting control (step S8) will be described with reference to FIG.

In this start control, it is determined in step S5 that the rotation speed Ne of the engine E is higher than the set rotation speed N _e1 based on various information read in step S2, and
The following procedure is performed on condition that the vehicle speed V is determined to be smaller than the set value V ₁ in step S7.

(Step S81) The gear ratio R of the continuously variable transmission T is adjusted to the LOW side, and the process proceeds to step S82.

(Step S82) It is judged whether or not the continuously variable transmission T has been shifted to LOW, and LOW
If not reached, the process returns to step S81, and if shifted to LOW, the process proceeds to step S83.

(Step S83) The gear shifting operation is stopped, the gear ratio R is maintained, and the process returns to step S2.

By such control, when the vehicle speed V is low and the vehicle is in a starting state, the gear ratio R of the continuously variable transmission T is held at LOW,
Optimal gear ratio R for starting even if the engine E speed is large
Is adjusted to a smooth start operation.

Moreover, when the engine E is stopped for some reason by performing the start control after the pushing control described above, the pushing control is given priority and the gear ratio R is changed from LOW to LOW. It is adjusted to the TOP side and set to the optimum state for pushing, and smooth operation is performed.

Jump control provided at the beginning of special control II (step
S10) is performed when the vehicle is in a traveling state through the initial control I, and is shown in FIG. 19 on condition that the drive wheel Wr is separated from the traveling road surface in step S9 following step S7. Done in steps.

Then, as a means for detecting the separation of the drive wheel Wr from the traveling road surface, for example, in the above-mentioned motorcycle,
This cushion unit 136
A configuration is conceivable in which a cushion switch that outputs a constant signal when is fully extended is provided. That is, when the vehicle reaches the jumping state, the cushion unit 136 is in a fully extended state. Therefore, by detecting the output signal from the cushion switch, it is determined whether or not the vehicle is in the jumping state. Judgment is made.

(Step S101) It is determined whether or not the duration of the jump (for example, the duration of the output signal from the cushion switch) has exceeded a certain time T ₁ , and if not, the process proceeds to step S102, If the time has passed, the process proceeds to step S103.

(Step S102) The gear ratio R is maintained at the gear ratio immediately before the jump, and the step
Return to S2.

(Step S103) The optimum gear ratio R ₁ is calculated based on the gear ratio immediately before the jump, and the process proceeds to step S104.

(Step S104) It is judged whether or not the actual gear ratio R matches the optimum gear ratio R ₁ obtained in step S103. If they do not match, the process proceeds to step S105, and if they match, Shifts to step S106.

(Step S105) In the direction of approaching the gear ratio R to the optimum gear ratio R ₁ , the continuously variable transmission T
Is operated and the process returns to step S104.

By this control, the gear shifting operation of the continuously variable transmission T is continuously performed until the actual gear ratio R and the optimum gear ratio R ₁ match.

(Step S106) After stopping the shift operation, the process returns to step S2.

In such control, in step S101, it is determined whether or not the jump duration time exceeds a certain time T _1, and the gear ratio R is adjusted thereafter, so that, for example, the vehicle travels on an uneven road surface. When the drive wheel Wr repeatedly jumps in small increments and the duration of the jump is short, the change in the vehicle speed V during the jump is small and the gear ratio R need not be adjusted. Therefore, the gear ratio immediately before the jump is maintained. Then drive wheels
When the driving force transmitted to Wr is appropriate and the duration of the jump is long, for example, a phenomenon in which the vehicle speed V drops on an uphill or a vehicle speed V increases on a downhill plate. Speed V during such a jump
By adjusting the gear ratio R corresponding to the change of the above, it is possible to apply an appropriate driving force to the drive wheels Wr at the time of landing, or prevent the engine E from over-rotating.

The lock / slip control (step S12) is performed in the procedure shown in FIG. 20 after it is determined in step S11 that the amount of change in the rotational speed of the drive wheel Wr is outside the set range.

In the following description, in order to clarify the description, the detailed procedure of step S11 is also included. Then, the procedure related to this step S11 is shown as step S11XX.

(Step S111) Calculate the difference (V _RR −V _F ) between the rotational speed V _{RR of} the drive wheel Wr and the previously measured rotational speed V _F of the drive wheel Wr, that is, the amount of change,
Whether the amount of change is zero or positive is determined, and if it is zero or positive, the process proceeds to step S112, and if negative, the process proceeds to step S113.

(Step S112) Whether the amount of change (V _RR −V _F ) in rotational speed of the drive wheel Wr calculated in step S111 exceeds the upper limit C ₁ of the range set as the control condition for this amount of change. (I.e., whether or not the driving wheel Wr is accelerated more than the set value) is judged, and if it is exceeded, it is determined that over-rotation due to slip has occurred in the driving wheel Wr, the process proceeds to step S121, and if it is not exceeded. Then, the process proceeds to step S113.

(Step S121) The difference (V _RR −V _FR ) between the rotational speed V _RR of the driving wheel Wr and the rotational speed V _FR of the driven wheel Wf is calculated, and this difference is set as the control condition for the rotational speed difference between the two. It is determined whether or not the upper limit value C ₃ of the specified range is exceeded (that is, whether the drive wheel Wr is rotated beyond the set value by the rotation of the driven wheel Wf), and if not, the process proceeds to step S113. However, if it exceeds, it is determined that over-rotation due to slip has occurred in the drive wheels Wr, and the process proceeds to step S122.

(Step S113) The change amount (V _RR −V _F ) of the rotational speed V _RR of the drive wheel Wr is the lower limit value C _{2 of the} range set as the control condition for this change amount.
(This value is negative) It is judged whether it is below (that is, the drive wheel Wr has been decelerated more than the set value), and if it is below, it is determined that the drive wheel Wr has reached the lock state. If it is not lower than step S123, the process proceeds to step S124.

(Step S123) The difference (V _RR −V _FR ) between the rotational speed V _RR of the driving wheel Wr and the rotational speed V _FR of the driven wheel Wr is calculated, and this difference is set as the control condition for both rotational speeds. Whether it is below the lower limit of the range C ₄ (which is negative) (ie the drive wheels
It is determined whether or not the rotation of Wr is lower than the rotation of the driven wheel Wf by a set value or more. If it is below, the process proceeds to step S125, and if it is not below, the process proceeds to step S124.

(Step S125) When the difference (V _RR −V _FR ) between the rotational speed V _RR of the driving wheel Wr and the rotational speed V _FR of the driven wheel Wf is below the lower limit value C ₄ ,
It is determined whether or not a certain period of time has elapsed. If not, the process proceeds to step S126, and if it has elapsed, the process proceeds to step S127.

(Step S126) A signal is output to the electric motor 86 to maintain the gear ratio R of the continuously variable transmission T at the gear ratio immediately before the start of over-rotation of the drive wheels Wr due to slip, and the process returns to step S2.

(Step S127) The estimated vehicle speed is calculated based on the rotation speed V _FR of the driven wheel Wf, and the process proceeds to step S128.

(Step S128) The optimum gear ratio R of the continuously variable transmission T is calculated according to the vehicle speed estimated in step S127, and the process proceeds to step S129.

(Step S129) The gear ratio R of the continuously variable transmission T is adjusted to the value calculated in step S128 by the electric motor 86, the gear ratio R is adjusted to the LOW side by a necessary amount, and then the process returns to step S2.

(Step S124) The previous rotational speed V _F of the drive wheel Wr is updated to the same value as the rotational speed V _RR of the drive wheel Wr detected this time, and the process proceeds to step S13.

(Step S122) The rotational speed V _{FR of} the driven wheel Wf and the previously measured rotational speed V _F of the driven wheel Wf (V _FR −V _F ), that is, the change amount is calculated, and the absolute value (| V _FR -V _F |) determines whether it has exceeded the set value C ₅ of the range set as the control condition (that is, whether it has been accelerated or decelerated more than the set value). Shifts to step S1210, and if it exceeds, it is determined that the vehicle is in an acceleration or deceleration state, and shifts to step S1211.

(Step S1210) In order to maintain the gear ratio R of the continuously variable transmission T at the gear ratio immediately before the start of over-rotation of the drive wheels Wr due to slip, the electric motor 86
A signal to and returns to step S2.

(Step S1211) Whether the amount of change in the rotational speed of the driven wheel Wf calculated in step S122 is positive or negative is determined. If negative, the process proceeds to step S1212, and if positive, the process proceeds to step S1213. Transition.

(Step S1212) The estimated vehicle speed is calculated based on the driven wheel rotation speed V _FR , and the process proceeds to step S1214.

(Step S1214) The optimum gear ratio R of the continuously variable transmission T is calculated according to the vehicle speed estimated in step S1212, and the process proceeds to step S1215.

(Step S1215) After the gear ratio R is adjusted to the LOW side by the necessary amount by the electric motor 86 so that the gear ratio R of the continuously variable transmission T becomes the value calculated in step S1214, the process returns to step S2.

(Step S1213) The estimated vehicle speed is calculated based on the rotation speed V _FR of the driven wheel Wf, and the process proceeds to step S1216.

(Step S1216) The optimum gear ratio R of the continuously variable transmission T is calculated according to the vehicle speed estimated in step S1213, and the process proceeds to step S1217.

(Step S1217) After the gear ratio R is adjusted to the TOP side by the necessary amount by the electric motor 86 so that the gear ratio R of the continuously variable transmission T becomes the value calculated in step S1216, the process returns to step S2.

Here, the operation of this control will be described by taking as an example the case where the motorcycle is driven on a traveling road surface having a muddy portion.

If the driving wheel Wr slips due to sudden opening of the throttle and slippage of the driving wheel Wr during traveling, the driving wheel Wr will be in a state close to idling, and the engine speed and the rotation speed of the driving wheel Wr will rapidly increase. Then, it is determined that the excessive rotation of the drive wheels Wr due to slip has started as the drive wheel rotation speed V _RR increases, and the gear ratio R of the continuously variable transmission T is maintained at the value immediately before the start of slip.

Also, if the driving wheel Wr slips due to sudden opening of the throttle when the vehicle is climbing on the road surface and reaching a muddy place on the road surface, the driving wheel Wr
Becomes a state close to idling, and the vehicle speed V sharply decreases because the vehicle is climbing uphill. Then, the drive wheel rotation speed
As V _RR rises, it is determined that the drive wheel Wr has started to over-rotate due to slip and that the driven wheel rotation speed V _FR has decreased, and the gear ratio R of the continuously variable transmission T is set to the gear ratio immediately before the start of slip. Adjusted to the LOW side of R.

On the contrary, if the drive wheels Wr slip when the throttle is suddenly opened when the vehicle reaches a muddy place down the inclined road surface, the drive wheels will be in a state close to idling, Since the vehicle is downhill, the vehicle speed is higher than when the slip started, that is, the vehicle is accelerated.
Then, it is determined that the driven wheel rotation speed V _FR has increased, and the gear ratio R of the continuously variable transmission T is adjusted to the TOP side.

As described above, when the frictional force between the drive wheel Wr and the traveling road surface is restored, the gear ratio R adapted to the actual vehicle speed is secured, and the driving force does not drop and sufficient acceleration is maintained. You can

On the other hand, while driving on a muddy road surface, sudden braking is applied to drive wheels.
When Wr is locked, the aforesaid locked state is detected as the rotational speed V _RR of the drive wheel Wr rapidly decreases, and the gear ratio R of the continuously variable transmission T is maintained at the value immediately before being locked.

Therefore, when the frictional force between the traveling road surface and the drive wheels Wr is restored, the gear ratio R adapted to the actual vehicle speed is secured, appropriate engine braking is obtained, or engine over-rotation is prevented.

On the other hand, the detection of the over-rotation state of the drive wheel Wr due to the slip or the escape from the locked state is performed by comparing the rotation speed V _RR of the drive wheel Wr and the rotation speed V _FR of the driven wheel Wf. Since the rotational speed V _FR of the driven wheel Wf is close to the actual vehicle speed, the drive wheel Wr for slipping as described above is used.
It is possible to accurately detect the excessive rotation state of the vehicle and the escape from the locked state, and it is possible to obtain the work of adjusting the gear ratio R in accordance with the actual vehicle speed.

Further, by performing this lock / slip control (step S12) in the latter stage of the jump control (step S10), it is possible to prevent over-rotation or deceleration of the drive wheel Wr during the jump from being judged to be a lock or a slip. Control is performed reliably.

The inertial running control (step S14) is performed according to the procedure shown in FIG. 21 on condition that the lock and slip are not generated in step S11 and the power transmission by the clutch mechanism C is cut off in step S13. Done.

(Step S141) It is judged whether or not the condition of the clutch one cycle before the control system is the clutch OFF as in the present time, that is, whether or not the clutch is OFF for the first time this time, and the clutch is disengaged for the first time. In this case, the process proceeds to step S142, and if the clutch was previously OFF, that is, the clutch is OFF.
If the state is the continuous state, the process proceeds to step S143.

(Step S142) The vehicle speed V _F and the gear ratio R _F at the time when the clutch is turned off are read based on the signals from the vehicle speed sensor Sc (Se) and the ratio sensor 128. Here, if the vehicle speed V _F and the gear ratio R _F have already been read, the new vehicle speed V _F
Then, the gear ratio R _F is updated and the process proceeds to step S143.

(Step S143) It is determined whether or not a predetermined time Ts has passed, and the predetermined time Ts
On the condition that has passed, the process proceeds to step S144.

(Step S144) A calculation for adding Ts to the previous elapsed time ΔT is performed, and the value after the addition is updated as a new elapsed time ΔT, and then step S145
Move to.

Here, when ΔT = 0, it means that the clutch is off for the first time, so the elapsed time ΔT is Ts,
When the clutch OFF state continues, the predetermined time Ts is sequentially added to calculate the clutch OFF duration.

(Step S145) The vehicle speed V _T after the elapsed time ΔT is read and the process proceeds to step S146.

(Step S146) ΔV = V _T −V _F , that is, the vehicle speed V _F at the time when the clutch is turned off and the vehicle speed V _T after the clutch is turned off.
And the difference is calculated, and the process proceeds to step S147.

(Step S147) Based on the duration ΔT calculated in step S144, the speed difference ΔV calculated in step S146, and the gear ratio R _F when the clutch is OFF read in step S142,
After obtaining the target gear ratio R _M from the map created in advance, the process proceeds to step S148.

(Step S148) The current gear ratio R is compared with the target gear ratio R _M obtained in step S147, and if R = R _M , then step S1
If R ≠ R _M , the process moves to step S1410.

(Step S149) When it is determined in step S148 that the current gear ratio R matches the target gear ratio R _M , the gear shifting operation of the continuously variable transmission T is stopped and the process returns to step S2.

(Step S1410) It is determined whether or not the current gear ratio R is larger than the target gear ratio R _M (is on the LOW side), and if it is larger than the target gear ratio R _M , the process proceeds to step S1411, If it is smaller, the process moves to step S1412.

(Step S1411) If the current gear ratio R is determined to be larger than the target speed ratio R _M is the electric motor 86 to match the current gear ratio R to the target speed ratio R _M and outputs a drive signal And continuously variable transmission T
Is operated to the TOP side, the gear shifting operation is stopped when the both coincide with each other, and then the process returns to step S2.

(Step S1412) When the current gear ratio R is smaller than the target gear ratio R _M (TOP
If it is on the side), the reverse operation to the operation in step S1411 is performed to operate the continuously variable transmission T to the LOW side, and then the process returns to step S2.

On the other hand, if it is determined in step S13 that the clutch is ON, in step S131 the ΔT calculated in step S144 is cleared, and then the process proceeds to step S15.

When the shift control of the continuously variable transmission T is performed based on such control, the clutch mechanism C is disengaged during traveling at a certain speed, the clutch disengaged state is continued for a certain period of time, and then the clutch is re-engaged. For example, maintain a gear ratio close to TOP until just before the corner, disengage the clutch at the same time as entering the corner, decelerate by braking, and re-engage the clutch when the corner is reached and drive. In the case of applying power to the wheel Wr to escape from the corner, follow steps S13 to S1412 to set the clutch
The target gear ratio R _M is set in accordance with the duration of OFF and the change in the vehicle speed V during that period (in the case of the above-described example, since the deceleration operation is performed, the negative vehicle speed change occurs, and step S1
At 47, the target gear ratio R _M is set to the LOW side of the gear ratio R _F at the time when the clutch is disengaged), and the actual gear ratio R is adjusted to this gear ratio R _M.

As a result, the continuously variable transmission T is adjusted to an appropriate gear ratio R (R _M ), and an appropriate driving force is applied to the drive wheels Wr when the clutch is reconnected.

Therefore, an acceleration operation that corresponds to the throttle operation can be obtained.

If the corner is slightly downhill and deceleration operation is not required, the vehicle speed rises while the clutch is disengaged, and at the time of re-driving, the value is higher than the value immediately before the clutch was disengaged. Furthermore, the gear ratio R closer to TOP is adjusted.

Further, by performing this inertial traveling control after the above-mentioned jump control and lock / slip control, even when the clutch mechanism C is disengaged during the jump or lock / slip of the vehicle, the operability of the vehicle is greatly affected. It is possible to ensure smooth operability by giving priority to jump control and lock / slip control.

In the present embodiment, the normal control III, which is performed subsequent to the special control II, is performed according to the procedure shown in FIG.

(Step S151) Based on the engine speed Ne, the throttle opening θ, the vehicle speed V, and the gear ratio R detected in step S2, “engine speed (N _e ) -gear ratio (R)” that is input in advance. As shown in FIG. 23, the target engine speed N _em corresponding to the actual gear ratio R on the boundary line B defining the appropriate engine speed region A is read from the “map”, and the target engine speed N is read. It compares the actual engine speed N _e and _em, when the actual direction of the engine speed N _e is high, the process proceeds to step S152, proceeds to step S153 otherwise.

Here, the target engine speed N _em can be regarded as the boundary line B.

(Step S152) Based on the current gear ratio R, that is, the inclination angle of the motor swash plate 20, the motor swash plate 20 is changed from a preset map.
The tilting speed of is calculated and the process proceeds to step S154.

(Step S154) A drive signal is output to the electric motor 86 to tilt the motor swash plate 20 at the tilting speed obtained in step S152, and TO
Shift to the P side and return to step S2.

As a result, the actual engine speed N _e is equal to the boundary line B.
Lowered towards.

(Step S153) It is determined whether or not the actual engine speed N _e is lower than the target engine speed N _em. If it is low, the process proceeds to step S155, and otherwise, the process proceeds to step S156.

(Step S155) Based on the current gear ratio R, that is, the inclination angle of the motor swash plate 20, the motor swash plate 20 is changed from a preset map.
The tilting speed of is calculated and the process proceeds to step S157.

(Step S157) A drive signal is output to the electric motor 86 to tilt the motor swash plate 20 at the tilt speed obtained in step S155, and LO
Shift to the W side and return to step S2.

(Step S156) By the time this step S156 is reached, the actual engine speed
As a result, it is determined that N _e and the target engine speed N _em match, so the shift operation is immediately stopped, and the process returns to step S2.

By repeating the above procedure, when the actual engine speed Ne coincides with the boundary line B, or when the actual engine speed Ne slightly exceeds the boundary line B, the proper engine speed region A is exceeded.
The shift operation is stopped when it is set inside the.

The control procedure will be specifically described below by taking a case where the actual engine speed Ne is higher than the proper engine speed region A as an example.

As shown in FIG. 7, it is assumed that the engine speed Ne is higher than the proper engine speed region A N _e1 and the gear ratio R at that time is R ₁ .

Here, first, the actual engine speed N _e1 and the actual gear ratio R
_Based on the proper engine speed N _em1 obtained from the relationship with _1, it is determined to be higher than the proper engine speed region A, and the gear ratio R is adjusted to the TOP side.

By such adjustment, the gear ratio R is reduced to R ₂ , and the engine speed Ne is also reduced from N _e1 to N _e2 .

Next, the reduced engine speed N _e1 and the gear ratio R ₂
Based on the proper engine speed N _em2 obtained from the relationship, the engine speed N _e2 is determined to be higher than the proper engine speed region A, and the gear ratio R is adjusted to the TOP side.

The above operation is sequentially performed, and finally, as shown in FIG. 23, the actual engine speed N _e is equal to the engine speed N _em0 within the proper engine speed region A including the boundary line B. At the same time, the gear ratio R at that time is set to R ₀ .

The final gear ratio R ₀ described above is obtained as a result of a series of control operations, is not a final target value, and serves as a criterion for determining whether the engine speed N _e is high or low.
N _em is not the target value during control.

Therefore, in the control operation described above, the target gear ratio
TOP of the actual gear ratio R without considering the change amount of R _M
Since the control is performed only by controlling the adjustment amount to the side, the control is extremely simplified.

Also, upon adjustment of the gear ratio R, as compared with a case where by setting the target speed ratio R _M to adjust the target speed ratio gear ratio toward R _M, to the speed ratio R ₀ to eventually reach The amount of adjustment is small, and as a result, the speed change speed can be improved.

On the other hand, when the actual engine speed N _e is lower than the proper engine speed region A, in the above-described control, the boundary line is set to the lower limit of the proper engine speed region A as shown in FIG. The same control is performed by setting the lower boundary line D for partitioning and setting the adjustment direction of the gear ratio R to the LOW side.

Further, in the present embodiment, in step S152 and step S155, the shift speed is changed according to the gear ratio R.

By this control, it is possible to maintain the speed of the rotation increase of the engine E and the shift speed of the continuously variable transmission T in an appropriate relationship.

For example, in a normal vehicle, as shown in Fig. 24,
As shown by the curve P ₁ , since the driving force given from the engine to the drive wheels is large, as shown by the curve N _e1 in the figure,
The engine speed is high and the transmission is TOP
When it is set to the side, as shown by the curve P ₅ in the figure, the driving force given from the engine to the drive wheels is small, so that as shown by the curve N _{e 5} in the figure, It has a characteristic that the ascending speed becomes slower, and as shown by the curve J in the figure, as the gear ratio goes to the TOP side,
It has a characteristic that the interval between the peaks of the driving force is narrowed.

Here, in order to maximize the characteristics of the engine E in the entire rotation range, it is effective to perform the shift control along the curve J. However, in the present embodiment, the tilting speed of the motor swash plate 20 causes the shift operation. By preparing the map so that it is fast in the initial stage and is gentle in the final stage, that is, it is fast in the LOW side and is gentle in the TOP side, it is possible to obtain control substantially along the curve J.

As a result, the speed of the rotation increase of the engine E and the speed change speed of the continuously variable transmission T are maintained in an appropriate relationship, and engine run-up on the LOW side and engine hunting on the TOP side are suppressed.

In addition, in FIG. 24, the gear ratio of the transmission is shown as five stages including LOW and TOP in order to facilitate understanding,
Subscripts 1 to 5 are attached to each from LOW to TOP, the curve P _n indicates the change curve of the driving force at each gear ratio, and N _en indicates the change in engine speed at each gear ratio. A curve is shown.

Then, by performing such normal control III in the latter stage of the special control II, when special traveling conditions are reached, control that immediately responds to changes in the traveling conditions is performed.

The above embodiment is an example, and various modifications can be made based on the type of vehicle to which it is applied.

[Effects of the Invention] As described above, the control method for a vehicle continuously variable transmission according to the present invention is a control method for a continuously variable transmission provided between an engine mounted on a vehicle and drive wheels. , Initial control, special control performed on condition that this initial control is determined to be unnecessary, and normal control performed on condition that this special control is determined to be unnecessary, the initial control, A) Detecting the operating status of each device installed in the vehicle,
Fail-safe control performed when there is an abnormality in these operations.

B) On condition that each device is operating normally, it is judged whether the engine speed is below a set value, and if it is below the set value, shift of the continuously variable transmission is performed. Push-out control that adjusts the ratio to a value between TOP and LOW.

C) In B), on the condition that the engine speed is determined to be equal to or higher than the set value, it is determined whether or not the vehicle speed is equal to or higher than the set value, and when it is determined to be equal to or lower than the set value, Start control that adjusts the gear ratio of the continuously variable transmission to LOW.

In addition, each of the special controls includes: D) the condition that the vehicle speed is determined to be equal to or higher than the set value in C), and it is determined whether or not the drive wheel is in contact with the ground, If it is determined that the variable speed has not been reached, the jump control for maintaining the gear ratio of the continuously variable transmission at a value immediately before the drive wheels are separated from the road surface or adjusting the gear ratio to an optimum value set based on this value.

E) On the condition that the drive wheel is in contact with the ground in D), it is determined whether the amount of change in the rotational speed of the drive wheel is within the set range, and it is determined that the change is outside the set range. In this case, the lock / slip control holds the gear ratio of the continuously variable transmission at a value immediately before the amount of change is out of the set range or adjusts it to an appropriate value.

F) When it is determined in E) that the amount of change in the rotational speed of the drive wheels is within the set range, it is determined that the vehicle clutch is disengaged, and it is determined that the clutch is disengaged. In addition, inertia traveling control that adjusts the gear ratio of the continuously variable transmission according to the elapsed time of power transmission interruption by this clutch and the amount of change in vehicle speed.

It is characterized by including each control of, the gear ratio of the continuously variable transmission, when the engine is stopped, at the start standby, when the jump,
When the vehicle is locked or slipped, and when the vehicle is traveling normally, the value is maintained at an appropriate value corresponding to all the states of the vehicle, and the smooth operation of the vehicle can be achieved.

[Brief description of drawings]

In the drawings, FIG. 1 is a flow chart for explaining a conventional method for controlling a continuously variable transmission for a vehicle, FIGS. 2 to 24 show an embodiment of the present invention, and FIG. 2 is a motorcycle. FIG. 3 is a vertical cross-sectional plan view of a hydrostatic continuously variable transmission installed in the power transmission system of FIG. 3, FIG.
IV-IV sectional view, FIG. 4A is an operation diagram of FIG. 4, FIGS. 5, 6, 7, and 8 are VV lines of FIG. 3, and VI-VI.
Line, sectional view taken along the line VII-VII and line VIII-VIII,
FIG. 9 is an external perspective view of the first distribution valve and the second distribution valve,
10 is a sectional view taken along line XX of FIG. 3, FIG. 10A is an operation diagram of FIG. 10, and FIGS. 11 and 12 are lines XI-XI and XI of FIG.
Sectional view taken along the line I-XII, FIG. 13 is a schematic view showing a hydraulic circuit, FIG. 14 is a plan view showing a motorcycle as a vehicle equipped with the hydrostatic continuously variable transmission, and FIG. FIG. 16 is a side view of the motorcycle shown in FIG. 14, FIG. 16 is a flowchart showing the whole one embodiment, FIG. 17 is a flowchart showing details of pushing control, and FIG. 18 is a flowchart showing details of start control. FIG. 19 is a flow chart showing details of jump control, FIG. 20 is a flow chart showing details of lock / slip control, FIG. 21 is a flow chart showing details of inertial running control, and FIG. 22 is showing details of normal control. FIG. 23 is a flowchart showing the relationship between the engine speed and the gear ratio in normal control, and FIG. 24 is an engine performance curve diagram for explaining the relationship between the engine and transmission in normal control. a ... Pump port, b ... Motor port, e ... First eccentric position, f ... Second eccentric position, g ... Clutch on position, h ... Clutch off position, D ... Discharge stroke region, E ... Engine, M
... hydraulic motor, P ... hydraulic pump, S ... suction stroke region, T
... continuously variable transmission, Ex ... expansion stroke area, Sh ... contraction stroke area,
C ... Clutch mechanism, Q ... Flow rate adjusting mechanism, G ... Hydraulic closed circuit, U ... Control means, 1 ... Crank shaft, 5 ... Input member, 7
… Pump cylinder, 9… Pump plunger, 10… Pump swash plate, 17… Motor cylinder, 19… Motor plunger, 20
... Motor swash plate, 25 ... Output shaft, 40 ... (Low pressure oil passage) Inner oil passage, 41 ... (High pressure oil passage) Outer oil passage, 45 ... First distribution valve, 46 ...
2nd distribution valve, 47 ... 1st eccentric wheel, 49 ... 2nd eccentric wheel, 51 ... 1st control ring, 57 ... Actuation ring, 62 ... Release ring, 64 ... Clutch lever, 66 ... Bell crank, 80 ... Inclination angle Control mechanism, 104
... Control lever, 124 ... Clutch sensor, 125 ... Actuator, 126 ... Flow rate sensor, 127 ... Actuator, 128 ...
Ratio sensor.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area F16H 59:56

Claims (1)

[Claims] 1. A control method for a continuously variable transmission provided between an engine mounted on a vehicle and driving wheels, which is performed on condition that initial control is performed and it is determined that this initial control is unnecessary. It is composed of special control and normal control performed on condition that the special control is determined to be unnecessary. These initial control and special control include the following control, and a continuously variable transmission for a vehicle. Control method. <Initial control> A) Detecting the operating state of each device mounted on the vehicle,
Fail-safe control performed when there is an abnormality in these operations. B) On condition that each device is operating normally, it is judged whether the engine speed is below a set value, and if it is below the set value, shift of the continuously variable transmission is performed. Push-out control that adjusts the ratio to a value between TOP and LOW. C) In B), on the condition that the engine speed is determined to be equal to or higher than the set value, it is determined whether or not the vehicle speed is equal to or higher than the set value, and when it is determined to be equal to or lower than the set value, Start control that adjusts the gear ratio of the continuously variable transmission to LOW. << Special control >> D) If the vehicle speed is judged to be equal to or higher than the set value in the above C), it is judged whether or not the driving wheels are in contact with the ground, and if it is judged that the driving wheels are not in contact with the ground. Jump control in which the speed ratio of the continuously variable transmission is maintained at a value immediately before the drive wheels are separated from the road surface or is adjusted to an optimum value set with this value as a reference. E) On the condition that the drive wheel is in contact with the ground in D), it is determined whether the amount of change in the rotational speed of the drive wheel is within the set range, and it is determined that the change is outside the set range. In this case, the lock / slip control holds the gear ratio of the continuously variable transmission at a value immediately before the amount of change is out of the set range or adjusts it to an appropriate value. F) When it is determined in E) that the amount of change in the rotational speed of the drive wheels is within the set range, it is determined that the vehicle clutch is disengaged, and it is determined that the clutch is disengaged. In addition, inertia traveling control that adjusts the gear ratio of the continuously variable transmission according to the elapsed time of power transmission interruption by this clutch and the amount of change in vehicle speed.