JPH07103309A - Continuously variable transmission - Google Patents

Abstract

PURPOSE:To obtain a reciprocal rotation condition easily without requiring a reciprocal rotation mechanism while reducing the burden by reducing a frequency in which large driving motive power is applied to a belt of a pulley mechanism in a continuously variable transmission by combining a speed change pulley mechanism and a planetary gear mechanism with each other. CONSTITUTION:Cam mechanisms 47 and 54 to contact/separate a sheave 35 in the inverse direction with/from a fixed sheave 34 between both pulleys 28 and 33, are arranged on the back side of a movable sheave 35 of the speed change pulleys 28 and 33, and an interlocking mechanism 64 is arranged to interlock both cam mechanisms 47 and 54 with each other so that belt winding diameters of both pulleys 28 and 33 change mutually in the inverse direction. A pinion carrying output gear 22 of a planetary gear mechanism 19 is switched to respective conditions of forward rotation, neutral or reverse rotation to a rotary shaft 2, and the speed is changed, and it is made adjustable in a neutral condition by a thrust balance of a belt 38 between both pulleys 28 and 33, and a speed change pulley mechanism 27 is used as a circulating motive power passage on the vehicle advance side which is frequently used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuously variable transmission,
In particular, it relates to a combination of a speed change pulley mechanism and a differential gear mechanism.

[0002]

2. Description of the Related Art As an example of a belt type continuously variable transmission,
A fixed sheave fixed to each of the pair of rotating shafts arranged in parallel to each other so as to rotate integrally and non-slidably with respect to each rotating shaft, and a V-shaped member between the fixed sheave and the fixed sheave to the rotating shaft. In addition to having a speed change pulley formed of a movable sheave that is arranged to face each other so as to form a belt groove and is rotatably integrated and slidably supported, a V belt wound between the belt grooves of both speed change pulleys is provided. It is known to include a speed change pulley mechanism that has a variable speed ratio between the rotary shafts by changing the effective radius with respect to the V belt by moving the movable sheave in the axial direction.

By the way, heretofore, in Japanese Patent Laid-Open No. 62-11815.
As disclosed in Japanese Patent Publication No. 9, a continuously variable transmission including the above-described speed change pulley mechanism and a planetary gear mechanism (differential gear mechanism) as a speed change gear mechanism has been proposed.

[0004]

In the continuously variable transmission equipped with the speed change pulley mechanism and the differential gear mechanism, when the output shaft is rotated from the stopped state using the differential gear mechanism, the power transmission path is changed. Is divided into two parts, the driving power and the circulation power. That is, in the closed circuit type differential gear device, one of the three gear elements of the differential gear mechanism is connected to the output shaft, and the rotation speed of the remaining one gear element of the differential gear mechanism is adjusted by adjusting the pulley ratio of the pulley mechanism. By changing the rotation direction and the rotation speed between the gear element and the remaining other gear elements, the rotation direction and the rotation speed of the output side gear element, that is, the output shaft are determined. However, at that time, driving power and circulating power are generated as power, and the output power is the driving power minus the circulating power. Which of the two power transmission paths from the input shaft to the output shaft is the drive power path or the circulating power path is determined by the rotation speed of the gear element in the differential gear mechanism, and the one with the higher rotation speed is driven. It becomes a power route.
The rotation speed of the gear element represents the peripheral speed of the gear element on the pitch circle.

In this case, in order to reduce the transmission load of the belt in the speed change pulley mechanism, the output shaft is used only in a predetermined direction with respect to the rotation of the input shaft, and
At that time, the belt side of the speed change pulley mechanism is used as a circulating power path through which circulating power smaller than driving power is transmitted.

However, since the output shaft rotates only in one direction, when it is mounted on a vehicle such as an agricultural machine, the rotation of the drive wheels is switched between the forward and reverse directions in order to switch between forward and backward traveling of the vehicle. A mechanism is required, and it is inevitable that noise and the like will occur when switching.

The present invention has been made in view of the above problems, and an object of the invention is to provide a continuously variable transmission which is a combination of a speed change pulley mechanism and a differential gear mechanism, by providing a predetermined means for the vehicle. Even when it is mounted on the vehicle, the forward / backward traveling can be switched without separately requiring a forward / reverse rotation mechanism.

[0008]

In order to achieve the above object, in the invention of claim 1, the speed change pulley mechanism side can be used as a drive power path for transmitting drive power, and this drive power path is By switching to the differential gear mechanism side or the speed change pulley mechanism side, it is possible to rotate the output part forward and reverse, and at that time, in order to reduce the belt transmission load of the speed change pulley mechanism as described above, In the state where it is frequently used, the speed change pulley mechanism side serves as the circulation power path.

Specifically, the continuously variable transmission of the present invention is
It is provided with first and second rotating shafts arranged in parallel with each other, a speed change pulley mechanism and a differential gear mechanism. The speed change pulley mechanism rotatably drives both rotary shafts in a variable speed manner, and includes a pair of speed change pulleys in which fixed sheaves and movable sheaves are respectively arranged and supported on the respective rotary shafts in opposite directions, The belt wound between both speed change pulleys and the rear side of the movable sheave of each speed change pulley are arranged on the back side of the movable sheave. A pair of drive mechanisms, an interlocking mechanism that interlocks the two drive mechanisms so that the belt winding diameters of the two speed change pulleys change in opposite directions, and changes the pulley ratio between the two pulleys; and the interlocking mechanism. The slack side span of the belt between the speed change pulley and the switching operation part to be operated is pushed so that the tension on the slack side span is larger than the tension generated corresponding to the pulley ratio between the pulleys. And a tension mechanism to generate.

Further, the differential gear mechanism has first to third gear elements connected to each other, and the first gear element is connected to the first rotary shaft, while the second gear element is connected to the second rotary shaft. Are linked to.

One of the first rotary shaft and the third gear element serves as an input portion and the other serves as an output portion, and the output portion is normally rotated with respect to the input portion by the switching operation of the switching operation portion. , And is switched to a neutral state or a reverse rotation state to shift gears.

Further, it is possible to adjust the movement to the neutral state by the thrust force balance of the belt between the transmission pulleys in the transmission pulley mechanism, and the first rotation shaft is used in the normal rotation state or the reverse rotation state, whichever is more frequently used. A differential gear mechanism and a rotation speed of a first gear element (peripheral speed on the pitch circle) connected to the second gear shaft are always higher than a rotation speed of a second gear element connected to the second rotation shaft. It is assumed that the gear ratio to the differential gear mechanism is set.

According to a second aspect of the present invention, in the speed change pulley mechanism, the directions of the movable sheaves of the speed change pulleys and the fixed sheave are opposite to each other.

Further, the drive mechanism is a cam mechanism, and each of the cam mechanisms includes a cylindrical rotating cam rotatably supported on the boss portion of the movable sheave of the speed change pulley via a bearing.
A fixed cam that comes into cam contact with the rotary cam, and a cam surface is formed on one of the rotary cam and the fixed cam, while the other is a cam follower that contacts the cam surface. The movable sheave is moved in the axial direction by the relative rotation of the fixed cam.

Further, the speed change mechanism has a single link connecting the rotating cams of both cam mechanisms.

According to the third aspect of the invention, when the continuously variable transmission is mounted on a vehicle, the input section is drivingly connected to the engine side mounted on the vehicle, while the output section is drivingly connected to the driving wheels of the vehicle. The side with high frequency of use is the forward side where the drive wheels are rotated so that the vehicle travels forward.

[0017]

With the above construction, the first aspect of the invention is the first aspect.
Since the speed change pulley mechanism and the differential gear mechanism are arranged in parallel between the second rotary shaft and the second rotary shaft, the power input using one of the first rotary shaft or the third gear element of the differential gear mechanism as an input unit is , One of the speed change pulley mechanism or the differential gear mechanism is used as a drive power path and the other is transmitted as a circulating power path,
The other of the first rotating shaft or the third gear element is output as an output unit. Then, by operating the switching operation section to change the pulley ratio of the speed change pulley mechanism, the output section is switched to the normal rotation state, the neutral state or the reverse rotation state with respect to the input section.

In the above-mentioned speed change pulley mechanism, when one of the drive mechanisms is operated by the operation of the switching operation unit to move the movable sheave of one speed change pulley in the axial direction, the other drive mechanism also operates accordingly. The movable sheave of the other speed change pulley moves by the operation opposite to the moving operation of the movable sheave with respect to the fixed sheave in the one speed change pulley, and the pulley ratio between the two pulleys is increased by the movement of both movable sheaves in the opposite direction. Be changed.

At this time, the respective drive mechanisms are arranged such that the fixed and movable sheaves of the respective speed change pulleys are located on opposite sides with respect to the axial direction, and the respective movable sheaves are opposed to each other from the rear side. Since both drive mechanisms are linked by the interlocking mechanism, when the continuously variable transmission is in the neutral state,
Both of the speed change pulleys in the speed change pulley mechanism are drive side pulleys (or driven side pulleys), the belt tension distribution between the two pulleys is balanced, and the belt thrust forces are the same.

However, when the continuously variable transmission changes from the neutral state to the forward rotation side or the reverse rotation side and the belt winding diameter of one pulley becomes larger than the other, the tension distribution of the belts on both pulleys becomes unbalanced. Then, the belt thrust of the pulley on the side where the belt winding diameter is increased becomes larger than that on the side where the belt winding diameter is decreased, and the difference in the belt thrust increases as the load increases. That is, when the continuously variable transmission changes from the neutral state even a little, due to the difference in the belt thrust, the winding diameter of the pulley on the side where the belt winding diameter increases increases so as to decrease, and A restoring force that returns to the neutral state acts on the neutral state, which allows the neutral state to be stably maintained.

Then, in the normal rotation state or the reverse rotation state, the first side connected to the first rotation shaft is the side that is used most frequently.
Since the differential gear mechanism and the gear ratio to the differential gear mechanism are set so that the rotation speed of the gear element is always higher than the rotation speed of the second gear element connected to the second rotation shaft. On the frequently used side, of the power transmission path from the input section to the output section, the differential gear mechanism side becomes the drive power path, and the speed change pulley mechanism side becomes the circulation power path. Circulating power that is smaller than the driving power is transmitted. On the other hand, on the less frequently used side, the rotation speed of the second gear element becomes higher than the rotation speed of the first gear element, and conversely to the above, the speed change pulley mechanism side is the drive power path and the differential gear mechanism side is the The driving power is transmitted to the belts of the speed change pulley mechanism, which are the circulation power paths. However, the driving power is transmitted to this belt is
Since the frequency of use is low, the frequency of applying large driving power to the belt in the speed change pulley mechanism is low. Therefore, it is possible to easily obtain the forward / reverse rotation state of the continuously variable transmission without reducing the forward / reverse rotation mechanism while reducing the burden on the belt.

According to the second aspect of the present invention, when the ratio of the number of revolutions of the output portion to the input portion, that is, the gear ratio of the transmission is changed, the rotating cams of the cam mechanisms of the two transmission pulleys have one link. Since it is linked so that it can be interlocked by the switching mechanism, the rotating cam of the cam mechanism of one pulley is rotated around the rotation axis, and the movable sheave of the pulley is moved in the axial direction by the cam contact with the fixed cam. And let
Along with this, the movable sheave of the other pulley moves in the opposite direction of the moving operation of the movable sheave with respect to the fixed sheave in the one pulley, and the movement of both movable sheaves in the opposite direction causes the pulley ratio of the speed change pulley mechanism to change. Is switched and changed.

At this time, for example, the rotating cam in each cam mechanism has a cam surface inclined at a predetermined inclination angle with respect to the surface orthogonal to the rotation axis, and the fixed cam is provided with a cam follower that moves on the cam surface. Then, a force acts on the cam surface of the rotating cam from the cam follower on the fixed cam in the direction perpendicular to the cam surface, and this force is a parallel component force in the direction parallel to the rotation axis and a right angle in the direction orthogonal to the rotation axis. The latter component acts at a right angle to the line connecting the axis of the rotary shaft and the connecting point to one link of the speed change mechanism. As a result of this action, a cam rotation reaction force that is perpendicular to the line connecting the axis of the rotating shaft and the connection point to the link, regardless of changes in the pulley ratio, and that is opposite to the right-angle component force, is generated. The reaction force acts on the boss portion of the movable sheave supporting the rotating cam so as to press the boss portion at the center position in the range where the belt of the pulley is wound. That is, the cam rotation reaction force on the boss is a clearance in the sliding portion between the boss and the rotary shaft, and is a moment acting in the direction of tilting the movable sheave with respect to the rotary shaft when the movable sheave receives thrust from the belt. The action acts to generate a moment in the direction opposite to, and the original moment is offset by this moment and becomes smaller, and the surface pressure distribution of the inner circumference of the boss of the movable sheave with respect to the outer circumference of the rotating shaft is dispersed in the axial direction. Such a large peak disappears and the sliding resistance of the boss portion decreases.
The load applied to the fixed point of the belt-generated thrust by the rotating cam by the amount that this sliding resistance becomes small (that is, the extraction thrust)
Is increased, in other words, the belt-generated thrust is transmitted to the rotating cam as a take-out thrust without great resistance.

In the speed change pulley mechanism, the rotating cams of both cam mechanisms are set so that the opening / closing forces between the speed change pulleys are reversed and the opening / closing forces between the two pulleys partially cancel each other out.
Since it is connected by a book link and the take-out thrust force of one cam mechanism is used for the belt thrust force of the other cam mechanism, when comparing this relationship to a seesaw, gear shifting is performed with a constant pulley ratio. When not present, the extraction thrust itself becomes larger in the case of the present invention than in the conventional case, but the extraction thrust becomes the same on the drive side and the driven side, and these are balanced with each other, and the thrust extraction efficiency is the same as in the conventional case. is there. However, when changing the pulley ratio, the difference between the belt-generated thrust and the take-out thrust is the load (operating force) required for gear shifting operation, so in the conventional case, the remaining take-up force is large due to the small take-out thrust. On the other hand, in the present invention, since the ejection thrust is large, conversely, the operation force can be correspondingly small. As a result, the resistance at the time of shifting to the neutral state becomes small due to the thrust force balance of the belt between the both shifting pulleys in the above shifting pulley mechanism, and the neutral state is smoothly adjusted.

According to the third aspect of the invention, the frequently used side is the forward side for driving the vehicle forward, and the forward side is higher than the frequency for the backward running, so that the continuously variable transmission is in the normal rotation state or The reverse rotation state can be appropriately made to correspond to the traveling mode of the vehicle.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show the entire configuration of a continuously variable transmission A according to an embodiment of the present invention. This transmission A is provided in a power transmission path between an engine and drive wheels in a vehicle such as a lawn mower or an agricultural machine. It is arranged.

1 and 2, reference numeral 1 denotes a casing of a continuously variable transmission A. The casing 1 is divided into first to third divided casings 1a to 1c from the left side to the right side in FIG.
It is divided into three parts.

Inside the casing 1, there are rotatably supported first and second rotating shafts 2 and 12, which are arranged parallel to each other in a substantially horizontal plane. The first rotating shaft 2 is an input unit (input shaft)
The gear shaft portion 3 and the pulley shaft portion 4 are divided into two parts. One end (the left end in FIG. 1) of the gear shaft portion 3 is projected to the outside of the casing 1, while the other end portion is located between the first and second divided casings 1a and 1b. A gear 5 having a boss portion 5a penetrating the second divided casing 1b is concentrically welded to the end thereof so as to rotate together. The middle portion of the gear shaft portion 3 is supported by the first split casing 1a, and the hollow boss portion 5a of the gear 5 is supported by the second split casing 1b via bearings 6 and 7, respectively. On the other hand, the pulley shaft portion 4 is arranged between the second and third divided casings 1b and 1c.
One end portion (the left end portion in FIG. 1) has a small diameter and is fitted into the boss portion 5a of the gear 5 which is integral with the gear shaft portion 3 so as to be rotatable and integrally removable. The other half of the pulley shaft portion 4 is a small diameter portion. As shown in FIG. 3, the small diameter portion has a sleeve 8 on the gear shaft portion 3 side and a sleeve 8 on the opposite side to the gear shaft portion 3. The bushes 9 are fitted to each other, and the ends of the sleeve 8 are fitted to the large diameter portion 9 a formed on the bush 9. Then, the pulley shaft portion 4 is
It is supported by the split casing 1c via a bearing 10.

Similarly, the second rotating shaft 12 is also divided into a gear shaft portion 13 and a pulley shaft portion 14. As shown in FIGS. 3 and 4, the gear shaft portion 13 penetrates the second split casing 1b, one end (the left end in FIG. 1) of which is the first split casing 1a, and the middle portion is the second split casing. It is supported by 1b via bearings 15 and 16, respectively. On the other hand, the pulley shaft portion 14 includes the second and third split casings 1.
It is a tubular member arranged between b and 1c, and the other end of the gear shaft 13 is spline-coupled to the one end (the left end in FIG. 1) so that the gear shaft 13 can be rotationally integrated and can be pulled out. The three divided casings 1c are supported via bearings 17. With this structure, the casing 1 is divided into the first and second divided casings 1a and 1b and the third divided casing 1c, and the rotary shafts 2 and 12 are respectively divided into the gear shaft portions 3 and 13 and the pulley shaft portion 4, respectively. By dividing into 14 and 2,
The continuously variable transmission A is unitized into a planetary gear mechanism 19 and a speed change pulley mechanism 27, which will be described later, and can be divided into two parts.

As shown in FIGS. 13 and 14, a driven pulley 91 composed of a V pulley is rotatably attached to the end of the first rotary shaft 2 projecting from the casing 1, and the driven pulley 91 and the engine E are integrated with each other. Between the drive pulley 92, which is a V pulley attached to the output shaft E1, is V
A belt 93 is wound around, and the power of the engine E is transmitted to the first rotating shaft 2 of the transmission A via the V belt 93.

A tension pulley 94 for pushing the loose side span of the V belt 93 from the back side is disposed between the pulleys 91 and 92, and the tension pulley 94 is rotatably attached to the tip shaft portion of the tension arm 95. The tension arm 95 is supported and the tension pulley 94 is attached to the belt 9
It is urged to rotate by a spring (not shown) in the direction of pushing 3. Further, an actuator 96 such as an air cylinder for rotating the tension arm 95 against the biasing force of a spring or the like in the direction opposite to the belt pressing direction is provided, and the tension pulley 94, the tension arm 95, the actuator 96, etc. A tension clutch 97 is configured to cut off the power transmission between the pulleys 91 and 92, that is, between the engine E and the transmission A by eliminating the thrust on the V-belt 93.

Further, a limit switch 98 for detecting that the continuously variable transmission A is in a neutral state by switching the operating lever 66 to a neutral position which will be described later.
Is provided, and the actuator 96 such as the air cylinder operates in response to a neutral detection signal from the limit switch 98. When the continuously variable transmission A is in neutral, the tension clutch 97 causes the engine E to shift gears. By interrupting the power transmission to the device A,
The transmission A is in a state of being drive-connected only to the wheel side.

In the casing 1, a planetary gear mechanism 19 as a differential gear mechanism arranged on the left end portion of the second rotary shaft 12 in FIG. 1 and both rotary shafts 2 and 12 are shifted by a V belt 38. A transmission pulley mechanism 27, which is driveably connected to the transmission, is housed therein.

The planetary gear mechanism 19 is, as shown in enlarged detail in FIG. 5, a second rotary shaft 12 formed on a gear shaft portion 13 located between the first and second divided casings 1a and 1b. A sun gear 20 as a gear element, a plurality of pinions 21, 21, ... That mesh with the sun gear 20, and bearings 24, 24 near the first split casing 1a of the gear shaft portion 13 of the second rotating shaft 12 described above. An output gear 22 (pinion carrier), which is rotatably supported and rotatably carries the pinions 21, 21, ..., and an output gear 22 (pinion carrier), which is arranged at the outermost periphery and has bearings 25, 25 on the gear shaft portion 13. And a ring gear 23 as a first gear element that is rotatably supported via a pinion and engages with the pinions 21, 21 ,. Ring gear 2
The outer circumference 3 is meshedly connected to the gear 5 on the first rotary shaft 2. The output gear 22 constitutes an output portion of the transmission A and is drivingly connected to driving wheels (not shown).

The speed change pulley mechanism 27 includes the first rotary shaft 2
The first transmission pulley 28 is disposed on the pulley shaft portion 4 between the second and third divided casings 1b and 1c. As shown in the enlarged detailed view of FIG. 3, the first transmission pulley 28 is keyed to the sleeve 8 on the pulley shaft portion 4 of the first rotation shaft 2 by a boss portion 29a so as to be integrally rotatable and non-slidable. A flange-shaped fixed sheave 29 and a flange-shaped movable sheave supported on the sleeve 8 (first rotating shaft 2) so as to be opposed to the fixed sheave 29 by a boss portion 30a so as to be slidable and relatively rotatable. 30 and a pulley groove 31 is formed between the sheaves 29 and 30. The movable sheave 30 is made of iron and has a boss portion 3
0a is integrally formed with the sheave body 30b by forging.

On the other hand, a second speed change pulley 33 having the same diameter as that of the first speed change pulley 28 is provided on the pulley shaft portion 14 of the second rotary shaft 12. As shown in the enlarged detail of FIG. 4, the second speed change pulley 33 has the same structure as the first speed change pulley 28, and the boss portion 3 is provided on the pulley shaft portion 14 of the second rotary shaft 12.
4a, a flange-shaped fixed sheave 34 which is rotationally integrally and non-slidably key-joined, and the pulley shaft portion 14 of the movable sheave 30 facing the fixed sheave 29 of the first transmission pulley 28 with respect to the fixed sheave 34. A flange-shaped movable sheave 35 that is slidably and relatively rotatably coupled to the boss portion 35a so as to face each other in the opposite direction.
A pulley groove 36 is formed between the sheaves 34 and 35.

A V-belt 38, which is a block belt, is wound between the pulley groove 31 of the first speed change pulley 28 and the pulley groove 36 of the second speed change pulley 33. Each movable sheave 30,3
5 is moved toward and away from the fixed sheaves 29 and 34, respectively, to change the belt winding diameter of the pulleys 28 and 33. For example, the movable sheave 30 of the first speed change pulley 28 is fixed to the fixed sheave 2
9 and the movable sheave 3 of the second speed change pulley 33.
When 5 is separated from the fixed sheave 34, the belt winding diameter of the first transmission pulley 28 is made larger than that of the second transmission pulley 33, so that the rotation of the first rotary shaft 2 is increased to the second rotary shaft 12. And communicate. On the other hand, conversely, when the movable sheave 30 of the first speed change pulley 28 is separated from the fixed sheave 29 and the movable sheave 35 of the second speed change pulley 33 is brought close to the fixed sheave 34, the belt winding of the first speed change pulley 28 is performed. By reducing the attachment diameter and increasing the belt winding diameter of the second speed change pulley 33, the rotation of the first rotary shaft 2 is decelerated and transmitted to the second rotary shaft 12.

As shown in FIG. 3, the V-belt 38 has a pair of endless tensions formed by embedding a plurality of core wires in the upper and lower central portions of a shape-retaining layer made of fiber-reinforced rubber or fiber-reinforced plastic. Bands 39, 39 and fitting portions 40a, 40a for fitting the tension bands, respectively, are provided on the left and right side surfaces of the pulley 2
8 and 33, which are a plurality of substantially trapezoidal blocks 40, 40, ... Abuttable on the side surfaces of the pulley grooves 31, 36, and the upper and lower surfaces of the tension bands 39 and the fitting portions of the blocks 40. The blocks 40, 40, ... Are locked and fixed to the tension bands 39, 39 in the belt longitudinal direction by engaging the concavo-convex portions (not shown) formed on the upper and lower surfaces of the 40a so as to correspond to each other. For high load transmission,
It can withstand high lateral pressure.

Movable sheave 30 of the first speed change pulley 28
A torque cam mechanism 42 is arranged between the boss portion 30 a and the pulley shaft portion 4 of the first rotating shaft 2. As shown in FIGS. 6 to 8, the torque cam mechanism 42 is a torque pin 43 formed of a linear pin fixed to the first rotating shaft 2 so as to have a tip portion protruding from the outer peripheral surface and penetrating in the radial direction thereof.
And a torque ring 44 rotatably fitted to the protruding end of the torque pin 43, and the boss portion 3 of the movable sheave 30.
Torque cam holes 45, 45 penetratingly formed in the torque pin 43 and engaging with the torque ring 44 at the tip of the torque pin 43.
Consists of. The torque cam holes 45 are shown in FIGS.
As shown in FIG. 3, the one side wall has a predetermined lead angle θ1 with respect to the direction parallel to the axis of the rotary shaft 2.
The forward cam surface 45 inclined by (for example, θ1 = 26 °)
Similarly, on the other side wall, a reverse drive side cam surface 45b is formed which is inclined by a lead angle θ2 (eg, θ2 = 8 ° <θ1) smaller than the forward drive side cam surface 45a. The torque cam mechanism 42 is actuated during each power transmission of A (vehicle) in the forward traveling state and the reverse traveling state, and the thrust on the belt 38 is applied in the opposite direction during the forward traveling and the reverse traveling. In order to obtain the movable sheaves 30 and 35, fixed sheave 2
It is designed to be moved to the 9, 34 side.

On the pulley shaft portion 4 of the first rotary shaft 2, a driving mechanism for bringing the movable sheave 30 into and out of contact with the fixed sheave 29 on the rear side of the movable sheave 30 in the first transmission pulley 28. A first cam mechanism 47 is provided. The cam mechanism 47 has a rotating cam 48, and the rotating cam 48 is fitted on the boss portion 30 a of the movable sheave 30 so as to cover the torque cam holes 45 and is cylindrically mounted.
The outer ring 1 is supported by external fitting via a bearing 49 so as to be relatively rotatable and axially movable integrally. Rotating cam 48
A pair of inclined cam surfaces 48a, 48a are formed on the end surface opposite to the first speed change pulley 28 at equal angular intervals (180 ° intervals) in the circumferential direction, and a turning lever 50 is turned on the outer circumference. It is projected integrally.

A cylindrical fixed cam 51 as a cam follower integrally formed concentrically with the first rotary shaft 2 in the second split casing 1b is arranged on the rear side of the rotary cam 48. Rollers 52, 52 are rotatably supported by 51 so as to be in contact with the cam surfaces 48a of the rotating cam 48 and roll.

On the other hand, on the pulley shaft portion 14 of the second rotary shaft 12, the movable sheave 3 of the second speed change pulley 33 is provided.
The second cam mechanism 5 as a drive mechanism for bringing the movable sheave 35 into and out of contact with the fixed sheave 34 on the back side of
4 are provided. The second cam mechanism 54 has the same configuration as the first cam mechanism 47, and is externally fitted and supported on the boss portion 35a of the movable sheave 35 via a bearing 55 so as to be relatively rotatable and axially movable integrally. It has a rotating cam 56. A pair of inclined cam surfaces 56a, 56a are formed on the end surface of the cam 56 on the side opposite to the second speed change pulley 33 at equal angular intervals in the circumferential direction, and a rotary lever 57 is integrally rotated on the outer circumference. It is projected.

On the rear side of the rotating cam 56, there is arranged a fixed cam 58 as a cam follower, which is formed by bulging the third divided casing 1c outside in a concentric cylindrical shape with the second rotary shaft 12, and this fixed Rollers 59, 59 that roll by contacting with the cam surfaces 56a of the rotating cam 56 are rotatably supported by the cam 58.

As shown in FIGS. 2 and 9, one end of a link 62 is connected to the tip of the rotary lever 50 of the first cam mechanism 47 via a pin 61, and the other end of the link 62 is the above-mentioned first. The rotation lever 57 of the two-cam mechanism 54 is connected to the tip of the rotation lever 57 via a pin 63.
7. Link mechanism 64 by link 62 and pins 61, 63
Is configured. By the interlocking mechanism 64, the cams 48, 56 of the cam mechanisms 47, 54 are interlocked with each other to rotate around the boss portions 30a, 35a of the movable sheaves 30, 35, and the rollers 52 are moved on the cam surfaces 48a, 56a. ，
By rolling 59, the movable sheaves 30 and 35 are moved in the axial direction to come into contact with and separate from the fixed sheaves 29 and 34, and the effective radii of the pulley grooves 31, 36, that is, the pulleys 28, 33. The belt winding diameter is variable, and the pulley ratio between the speed change pulleys 28 and 33 is changed.

Further, as shown in FIG. 15, in the interlocking mechanism 64 of the speed change pulley mechanism 27, the second cam mechanism 54 is used.
One end of a rod 65 is connected to the tip of the rotary lever 57, and the other end of the rod 65 is connected to an operation lever 66 as a switching operation unit via the rod. This operation lever 66 is, for example, a forward maximum speed position around the swing shaft,
It swings back and forth between the neutral position and the reverse maximum speed position.The shifting pattern is such that when moving from the reverse maximum speed position through the neutral position to the forward maximum speed position, it is once perpendicular to the turning direction at the neutral position. It is designed to move in the direction. The rod 67 is connected to the end portion of the operating lever 66, and the switching mechanism of the operating lever 66 actuates the interlocking mechanism 64 to rotate the rotating arms 50 and 56 protruding from the rotating cams 48 and 56. 5
7 is rotated between the forward maximum speed position, the neutral position and the reverse maximum speed position (see FIG. 2), and the transmission pulley mechanism 27
By changing the pulley ratio of the output gear 22 (output unit) as the pinion carrier of the planetary gear mechanism 19 to the first
The rotating shaft 2 (input portion) is switched to a normal rotation state, a neutral state, or a reverse rotation state to change the speed. In the neutral state, the belt winding diameter of the first speed change pulley 28 is, for example, 1.
It is configured so that the belt winding diameter of the second speed change pulley 33 is 72 mm, for example. Further, by setting the planetary gear mechanism 19 and the coupling gear ratio for the planetary gear mechanism 19, the first rotating shaft 2 is rotated when the output gear 22 is rotated in the reverse direction with respect to the first rotating shaft 2.
The rotation speed of the ring gear 23 that is drive-connected to is higher than the rotation speed of the sun gear 20 that is connected to the second rotating shaft 12.

Further, there is provided a dead zone 68 for making it impossible to transmit the operating force of the operating lever 66 to the interlocking mechanism 64. The dead zone 68 is provided, for example, at a pin member 69 provided on the opposite side of the rotation lever 38 of the rod 65 and at an end of the rod 67 on the operation lever 66 side, and the length of the rod 67 is provided on the pin member 69. And an engaging member 71 in which an engaging portion 70 that engages in the direction is formed.
Reference numeral 0 denotes a long groove (or a long hole) that slidably engages the pin member 69 by a predetermined distance, and the relative movement of the pin member 69 at the engaging portion 70 causes the operation lever 66 to be in the neutral position. At this time, the operating force of the operating lever 66 cannot be transmitted to the interlocking mechanism 64.

The first and second speed change pulleys 28,
A pair of spans 38a of a V-belt 38 stretched between 33,
A tension mechanism 73 is provided which generates a belt thrust by pressing the span of the loosening side of 38b outward from its inner surface to give tension to the belt 38. As shown in the enlarged detail in FIG. 4, the tension mechanism 73 has a boss portion 75 via a collar 74 on a bearing portion that is provided concentrically around the second rotary shaft 12 in the second split casing 1b.
First tension arm 75 in which a is rotatably supported
And a second tension arm 76 having a boss portion 76a rotatably supported on the boss portion 75a of the first tension arm 75.
The boss portion 76a of No. 6 is formed with a notch 76b through which the first tension arm 75 penetrates. As shown in FIG. 2, the first tension arm 75 extends toward the first rotating shaft 2 and its tip portion is bent upward. In addition, FIG.
As will be described in detail in an enlarged manner, one end of a tension shaft 77 extending parallel to both the rotary shafts 2 and 12 is fixedly attached to the intermediate portion of the first tension arm 75, and the other end of the tension shaft 77 is attached to each transmission pulley 28. , 33 pulley pulley grooves 31, 3
A first tension pulley 78, which is located at the sixth portion and is capable of pressing one (upper) span 38a of the V belt 38 from the inner surface, is rotatably supported by a bearing 79 at the other end. On the other hand, one end of a tension shaft 80 extending parallel to both the rotary shafts 2 and 12 is attached and fixed to the tip end portion of the second tension arm 76, and the other end of the tension shaft 80 is the pulley groove 31 in each of the speed change pulleys 28 and 33. ，
The second span which is located at the portion 36 and is capable of pressing the other (lower) span 38b of the V-belt 38 from the inner surface to the other end thereof.
A tension pulley 81 is rotatably supported via bearings (not shown). The positions of the tension pulleys 78 and 81 are such that the outer surfaces of the tension pulleys 78 and 81 are always in contact with a part of the inner surface of the belt 38 and can press the belt 38 regardless of the axial movement of the belt 38 due to the gear shift. It is set.

A spring attachment arm 82 extending upward is integrally attached to the boss portion 76a of the second tension arm 76, and between the tip of the spring attachment arm 82 and the tip of the first tension arm 75. Is a tension spring 8
3, the first tension arm 75 is rotated clockwise by the spring force of the tension spring 83 in FIG. 2, and the second tension arm 76 is rotated counterclockwise in FIG. The tension pulleys 78 and 81 press the inner surfaces of the spans 38a and 38b of the V-belt 38, respectively. The tension biasing force of the tension spring 83 with respect to the tension arms 75 and 76 causes the tension pulleys 78 and 81 to loosen the spans 38 a and 3 of the belt 38.
8b is set to be pressed with a tension larger than the maximum tension generated in the loose side spans 38a, 38b,
The belt thrust is generated by this tension.

Further, the above tension pulleys 78, 8
1 is externally fitted and fixed to the outer surface of the outer race of the bearing 79 as shown in detail in FIGS.
Both side surfaces of each tension pulley 78, 81 in cross section have an angle parallel to the side surfaces of the pulley grooves 31, 36 of the speed change pulleys 28, 33.
The inclination angle θ3 of the side surface corresponds to the sectional angle of the pulley grooves 31 and 36, and the axial length of the outer peripheral surface of each tension pulley 78, 81 is smaller than the width on the inner surface side of the belt 38.
The tension pulleys 78 and 81 are made of fiber reinforced resin mixed with polyamide fiber (specifically,
For example, 66 Nylon resin mixed with 30% of glass fiber).
The contact sound for 0, 40, ... Is reduced.

Next, the operation of the above embodiment will be described. The in-vehicle engine E is drivingly connected to the first rotary shaft 2 of the continuously variable transmission A through the driving and driven pulleys 92, 91 and the V belt 93, and the pinion 21, of the planetary gear mechanism 19,
Since the output gear 22 as a pinion carrier that supports 21, ... Is drivingly connected to the drive wheels of the vehicle, the rotational power of the engine E is transmitted to the drive wheels after being speed-shifted by the continuously variable transmission A. At this time, in the transmission A, the planetary gear mechanism 19 and the transmission pulley mechanism 27 are arranged in parallel in the power transmission path between the first rotary shaft 2 which is the input portion and the output gear 22 which is the output portion. When the transmission A is in operation, the power input from the first rotary shaft 2 is
After being transmitted to the speed change pulley mechanism 27, the gear 5 on the first rotary shaft 2 and the planetary gear mechanism 19, the output power is output from the output gear 22 as a pinion carrier in the planetary gear mechanism 19.

(Neutral) Specifically, when the operation lever 66 is positioned at the neutral position,
The output gear 22 of the planetary gear mechanism 19 has stopped rotating,
The continuously variable transmission A is in the neutral state and the engine E
Is not transmitted to the drive wheels, and the vehicle stops.

In this neutral state, the belt winding diameter of the first speed changing pulley 28 of the speed changing pulley mechanism 27 is 108 mm, the belt winding diameter of the second speed changing pulley 33 is 72 mm, and the pulley ratio is 0. At a predetermined value of 0.666, both the first and second speed change pulleys 28 and 33 are on the drive side (or the driven side).

Further, the tension spring 83 of the tension mechanism 73
Since the first tension arm 75 is urged in the clockwise direction in FIG. 2 and the second tension arm 76 is urged in the counterclockwise direction by the spring force of the control lever 66 in the neutral position, , The first tension pulley 78 is the upper span 38 of the V-belt 38 in FIG.
The inner surface of a and the second tension pulley 81 press the inner surface of the lower span 38b with the same pressing force.

When the operating lever 66 is positioned at the neutral position, this is detected by the limit switch 98, and the actuator 96 such as the air cylinder in the tension clutch 97 is activated in response to the neutral detection signal from the limit switch 98. Then
The tension arm 95 is rotated in the direction opposite to the direction in which the tension pulley 94 is pressed against the belt 93 against the biasing force of a spring or the like, and is pressed against the loose side span of the V belt 93 between the drive and driven pulleys 92 and 91. Is stopped, power transmission between the engine E and the transmission A is cut off,
The transmission A is connected only to the drive wheels.

At this time, in the speed change pulley mechanism 27, the fixed sheaves 29, 34 and the movable sheaves 30, 35 of the speed change pulleys 28, 33 are arranged so as to be located on the opposite sides with respect to the axial direction. Since the cam mechanisms 47 and 54 that bring the movable sheaves 30 and 35 into contact with and separate from the fixed sheaves 29 and 34 facing each other from the back side are linked by the interlocking mechanism 64, in the neutral state, both the transmission pulleys 28 and 33 will eventually move. Also on the drive side (or the driven side), the tension distribution of the belt 38 on both pulleys 28 and 33 is balanced, and the belt thrust forces are the same.

Then, in this neutral state,
Due to an external load from the driving wheels, the rotation of the output gear 22 with respect to the first rotating shaft 2 changes to the forward rotation side or the reverse rotation side even a little, and the belt winding diameter of one of the first or second speed change pulleys 28 and 33 changes to the other. More than two pulleys 2
8 and 33, the tension distribution of the belt 38 becomes unbalanced, and the belt thrust of the pulley 28 (or 33) on the side where the belt winding diameter is increased becomes smaller.
(Or 28), and the difference in the belt thrust increases as the load increases. This means that if the continuously variable transmission A changes from the true neutral state,
Due to the difference in the belt thrust, the winding diameter of the pulley 28 (or 33) on the side where the belt winding diameter is increased changes so as to be small, and a restoring force that automatically returns to the neutral state acts. Means that. In this embodiment, since the operation force transmission path from the operation lever 66 to the interlocking mechanism 64 is provided with the dead zone portion 68 for disabling the operation force of the operation lever 66 in the neutral state to the interlocking mechanism 64, When trying to return to the neutral state, the pin member 69 in the dead zone portion 68 freely moves at the engaging portion 70, and the restoration to the neutral state is not restricted. As described above, the continuously variable transmission A itself has a self-locking function to restore the neutral state. Therefore, if the tension clutch 97 cuts off the power on the input side (engine E side), the neutral state is stabilized. Therefore, the vehicle does not move carelessly and the stopping stability at the time of neutral can be improved.

Since the rotating levers 50 and 57 of the cam mechanisms 47 and 54 on the side of the speed change pulleys 28 and 33 are linked by the link 62, the pulley ratio of the speed change pulley mechanism 27 is changed by switching the operation lever 66. Can be changed to the output gear 22 of the planetary gear mechanism 19, that is, the output of the continuously variable transmission A in the normal rotation or reverse rotation state, and the rotation speed thereof can be increased.

(For forward movement) That is, when the operation lever 66 is positioned at the forward movement position from the neutral state, the operation lever 66 is connected to the rotation lever 57 on the outer circumference of the rotation cam 56 in the second cam mechanism 54. Therefore, in the state of switching to the forward position, the cam 56 moves around the boss portion 35a of the movable sheave 35 in the second transmission pulley 33 while rolling the cam rollers 59, 59 on the cam surfaces 56a, 56a, respectively. Rotate in one direction. As a result, the cam surface 56a is pushed by the roller 59 and the cam 56
Moves on the second rotary shaft 12, and the movable sheave 35, which is integrated with the cam 56 via the bearing 55, moves in the same direction to approach the fixed sheave 34. As a result, the second speed change pulley 33 is closed and the belt winding diameter is increased from 72 mm in the neutral state to a maximum of 120 mm. Due to the increase in the belt winding diameter, the V-belt 38 is pulled toward the second speed change pulley 33 side. To be

At the same time, the operating lever 66 is
Is switched to the forward position, the second speed change pulley 33
In synchronization with the movement of the movable sheave 35 of the first cam mechanism 47.
Of the second cam mechanism 5 on the first rotary shaft 2.
It rotates in the same direction as the cam 56 of No. 4. The rotation of the cam 48 eliminates the pressing force on the cam roller 52.
Therefore, the tension of the belt 38 moving to the side of the second speed change pulley 33 causes the cam 48 and the bearing 49 thereof to move.
The movable sheave 30 connected through the fixed sheave 2
The sheaves 29 and 30 are moved away from each other, and the first transmission pulley 28 is opened by the separation of the sheaves 29 and 30 to reduce the belt winding diameter from 108 mm in the neutral state to a minimum of 60 mm. As a result, the belt winding diameter of the second speed change pulley 33 becomes larger than that of the first speed change pulley 28, and the rotation of the second rotary shaft 12 is accelerated to increase the first speed.
It is transmitted to the rotary shaft 2. With this pulley ratio, the output gear 22 as the pinion carrier rotates in the reverse direction with respect to the first rotation shaft 2, and the drive power is rotationally driven in the forward direction of the vehicle by the output power of the engine E to move the pulley ratio forward. By changing the position to the maximum speed position, the rotational speed of the output gear 22 in the forward rotation direction, that is, the forward speed can be increased.

At this time, the input power is set as a drive power path through the gear 5 and the ring gear 23 of the planetary gear mechanism 19 to the output gear 22, and the sun gear 20 of the planetary gear mechanism 19 drives the second rotary shaft 12 to Speed change pulley mechanism 27
Is transmitted as a circulating power route. That is, generally, the frequency of use of the vehicle in the forward drive state is higher than that in the reverse drive, and since the speed change pulley mechanism 27 serves as the circulation power route during the forward drive, the drive power of the belt 38 is high frequently over a long period of time as a whole. It is possible to transmit a circulating power smaller than that, and it is possible to reduce the transmission load of the belt 38 even at the time of high output in a forward state where it is frequently used.

Further, in a state where the speed change pulley mechanism 27 serves as a circulating power path, the second speed change pulley 33 functions as a drive side pulley, while the first speed change pulley 28 functions as a driven side pulley, so that the belt 38 on the upper side in FIG. Although the span 38a of the V belt 38 is on the loose side, the first tension pulley 78 is
2, the tension springs 75 and 76 rotate in opposite directions so that the second tension pulley 81 presses the lower span 38b.
3, the second tension pulley 81 pressing the inner surface of the tension side span 38b moves upward in FIG. 2, and the second tension arm 76 rotates clockwise. As a result, the tension spring 83 is extended, the first tension arm 75 also rotates clockwise by that amount, and the first tension pulley 78 is on the loose side of the belt 38 in FIG. The inner surface of is pressed with a predetermined pressing force to obtain the belt tension.

Further, the boss portion 30a of the movable sheave 30 of the first speed change pulley 28 and the pulley shaft portion 4 of the first rotary shaft 2 are arranged.
A torque cam mechanism 42 is provided between the torque cam mechanism 42 and the torque cam mechanism 45, and forward and backward cam surfaces 45a and 45b are formed on both side walls of each torque cam hole 45 of the torque cam mechanism 42. When the movable sheave 30 and the first rotating shaft 2 rotate relative to each other due to the transmission load of the movable sheave 3, the forward cam surface 45a of each torque cam hole 45 comes into contact with the torque ring 44 at the tip of the torque pin 43.
0 is pushed in the axial direction to move away from the fixed sheave 29, and the movement of the movable sheave causes the rotating cam 48 of the first cam mechanism 47, the interlocking mechanism 64, and the second cam mechanism 54.
The movable sheave 35 of the second speed change pulley 33 is pressed toward the fixed sheave 34 side via the rotating cam 56, and the thrust of the speed change pulley 33 with respect to the belt 38 can be increased.

The tension spring 8 of the tension mechanism 73 is
Both tension arms 75 and 76 are urged to rotate in opposite directions by the urging force of 3, and the tension pulleys 78 and
81 is the slack side spans 38a, 38 of the belt 38, respectively.
The inner surface of the belt b is pressed, and a tension is applied to the belt 38 by this pressing. However, since this tension is larger than the maximum tension generated in the loose side spans 38a and 38b, the belt tension acts on the pulleys 28 and 33 of the belt 38. A wedge effect is generated to generate thrust, and this thrust causes both pulleys 28,
Power is transmitted between 33 via the belt 38.

(Reverse travel) On the other hand, when the operation lever 66 is positioned at the reverse travel position, the cam 48 of the first cam mechanism 47 causes the cam surfaces 4 of the respective cam surfaces 4 to switch to the reverse travel position.
While rotating the cam roller 52 on the 8a, the cam roller 52 rotates in the other direction around the boss portion 30a of the movable sheave 30 of the first transmission pulley 28. As a result, the cam surface 48a is pushed by the roller 52 and the cam 48 moves on the first rotary shaft 2, and the movable sheave 30 that is integral with the cam 48 moves in the same direction and approaches the fixed sheave 29. . As a result, the first speed change pulley 28 is closed and the belt winding diameter is increased from 108 mm in the neutral state to a maximum of 120 mm. Due to the increase in the belt winding diameter, the V-belt 38 is pulled toward the first speed change pulley 28 side. To be

Further, the cam 56 of the second cam mechanism 54 is moved to the second position as the operation lever 66 is switched to the reverse position.
The rotary shaft 12 is rotated in the same other direction as the cam 48 of the first cam mechanism 47. The rotation of the cam 56 eliminates the pressing force on the cam roller 59. Therefore, the first
Due to the tension of the belt 38 that moves to the speed change pulley 28 side,
The cam 56 and the movable sheave 35 connected thereto via the bearing 55 move on the second rotary shaft 12 in the direction away from the fixed sheave 34, and the separation of the sheaves 32, 33 opens the second transmission pulley 33. The belt winding diameter is reduced from 72 mm in the above neutral state to a minimum of 60 mm. As a result, the belt winding diameter of the first speed change pulley 28 becomes larger than that of the second speed change pulley 33.
The rotation of the rotary shaft 2 is accelerated and transmitted to the second rotary shaft 12. With this pulley ratio, the rotation direction of the output gear 22 is in the normal rotation state with respect to the first rotation shaft 2, and the drive power is driven to rotate in the reverse direction of the vehicle by the output power of the engine E, and the pulley ratio is set to the maximum reverse speed. By changing the position, the rotational speed of the output gear 22 in the reverse direction, that is, the reverse speed can be increased.

At this time, contrary to the above-described forward movement, the input power is driven by the path from the speed change pulley mechanism 27 or the second rotary shaft 12 to the sun gear 20 of the planetary gear mechanism 19 as the drive power path. From the output gear 22 as the pinion carrier to the pinion 21, 21 ,.
3 and the gear 5 are transmitted to the first rotary shaft 2 as a circulating power route.
Is a driving power path, a large driving power acts on the V-belt 38, which may reduce its durability. However, as described above, the frequency of use of the vehicle in the reverse drive state is generally lower than that in the forward drive. Since the V-belt 38 is low, a high transmission load is applied to the V-belt 38 for only a short time, and the durability of the belt 38 is not significantly reduced.

In this reverse drive state, the first speed change pulley 28 becomes the drive side pulley while the second speed change pulley 33
Is the driven pulley, and the lower span 38b of the belt 38 in FIG. 2 is the loose side. At this time as well, since both tension arms 75 and 76 are urged to rotate in the reverse direction by the tension springs 83, the tension side span 38a is the same as above.
The first tension pulley 78 pressing the inner surface moves downward in FIG. 2, the first tension arm 75 rotates counterclockwise, and the second tension arm 76 also rotates due to the spring force of the tension spring 83. By rotating counterclockwise, the second tension pulley 81 presses the inner surface of the lower span 38b on the loose side of the belt 38 with a predetermined pressing force to obtain the belt tension.

Further, in this reverse drive state, when the movable sheave 30 of the first shift pulley 28 and the first rotating shaft 2 rotate relative to each other due to the transmission load of the shift pulley mechanism 27, the reverse cam surface 45b of each of the torque cam holes 45 described above. Comes into contact with the torque ring 44 at the tip of the torque pin 43 to move the movable sheave 30 in the axial direction in the direction toward the fixed sheave 29, and the movement of the movable sheave 30 causes the belt 3 in the first transmission pulley 28 to move.
The thrust on 8 can be increased.

Therefore, in this embodiment, as described above, the planetary gear is set so that the rotation speed of the ring gear 23 is always higher than the rotation speed of the sun gear 20 on the forward side, which is frequently used in the forward or reverse traveling state of the vehicle. Since the gear ratio to the mechanism 19 and the planetary gear mechanism 19 is set, the frequency of transmitting small circulating power to the belt 38 of the speed change pulley mechanism 27 is increased, and the large driving power is transmitted to the belt 38. The frequency of the transmitted state can be reduced, and therefore, the load on the belt 38 can be reduced, and the forward / reverse state of the continuously variable transmission A can be easily obtained without separately providing the forward / reverse mechanism.

Further, the boss portion 30 of the movable sheave 30, 35 in each of the transmission pulleys 28, 33 of the transmission pulley mechanism 27.
a, 35a, the rotation cam 48 of each cam mechanism 47, 54,
56 is supported via bearings 49 and 55, and the rotary levers 50 and 57 on the outer circumferences of both rotary cams 48 and 56 are connected by one link 62. Therefore, when shifting the speed of the shift pulley mechanism 27, A force acts on the cam surfaces 48a, 56a of the rotating cams 48, 56 from the rollers 52, 59 supported by the fixed cams 51, 58 in a direction perpendicular to the cam surfaces 48a, 56a, and the rotary shafts 2, 12 of this force are applied. When the perpendicular component force in the orthogonal direction acts at right angles to the line connecting the axis of the rotating shafts 2 and 12 and the connecting point to the link 62, the axis of the rotating shafts 2 and 12 and the connecting point to the link 62 are Despite the change in the pulley ratio, a cam rotation reaction force that is perpendicular to the line connecting the lines and that is opposite to the above-mentioned right angle component force is generated, and this cam rotation reaction force is generated by the rotation cams 48, 56.
Boss 30 of movable sheave 30, 35 supporting
a, 35a, the boss portion 30 at the center position in the range in which the belt 38 of the pulleys 28, 33 is wound.
It acts so as to press a and 35a. That is, the cam rotation reaction force on the boss portions 30a and 35a is
When the movable sheaves 30 and 35 receive thrust from the belt 38, the movable sheaves 30 and 35 are moved by the clearances in the sliding portions between the rotary shafts 2 and 0a and 35a.
12 acts to generate a moment in the direction opposite to the moment acting in the tilting direction, and the original moment is offset by this moment and becomes smaller, and the inner circumference of the boss portions 30a, 35a of the movable sheaves 30, 35 rotates. Axis 2,
12 The surface pressure distribution on the outer circumference is dispersed in the axial direction, and the sliding resistance of the boss portions 30a and 35a is reduced. The rotation cam 4 of the thrust generated by the belt corresponds to the decrease in the sliding resistance.
Load applied to fixed points by 8,56 (that is, extraction thrust)
Is increased, in other words, the belt-generated thrust is transmitted to the rotating cams 48 and 56 as extraction thrust without great resistance. And when changing the pulley ratio,
Since the difference between the belt-generated thrust and the take-out thrust is the load (operating force) required for the gear shifting operation, the larger the take-out thrust is, the conversely the smaller the operating force is required. As a result, the resistance at the time of shifting to the neutral state due to the thrust balance of the belt 38 between the transmission pulleys 28 and 33 in the transmission pulley mechanism 27 becomes small, and the neutral state is smoothly adjusted, so that the neutral state is further improved. It can be held stably.

The first tension pulley 78 always presses the upper span 38a of the V-belt 38 in FIG. 2, and the second tension pulley 81 constantly presses the lower span 38b of the V-belt 38. 76
Is urged to rotate in the reverse direction by a tension spring 83, and the belt 3
Since the pressing force for the loose side span 38b (or 38a) is obtained by the return of the tension side span 38a (or 38b) of 8, the tension side of the belt 38 is changed as described above with the switching between forward and reverse. Even if the loose side span is switched, both tension pulleys 78, 8
While keeping the distance between 1 constant, the loose side span can be automatically pressed, and stable belt tension can be obtained.

Moreover, since each tension arm 75, 76 is urged to rotate by using the tension spring 83, there is no risk of buckling of the spring as in the case of using a compression spring, and an appropriate spring constant is obtained. It is also possible to stabilize the belt tension. Incidentally, in this way, both spans 38 of the belt 38 are
The inner surfaces of a and 38b are respectively tension pulleys 78 and 81.
Instead of pressing with a pair of tension pulleys, the pair of tension pulleys are arranged so that the back surfaces of the spans 38a and 38b of the belt 38 can be pressed, and the tension arms supporting the tension pulleys are rotated in the belt pressing direction by tension springs. A biasing force may be applied.

Further, the above two tension pulleys 7
The axial length of each outer peripheral surface of each of the belt pulleys 8, 81 is smaller than the width of the inner surface of the belt 38, and the tension pulleys 78,
Since 81 is arranged between both spans 38a and 38b of the belt 38 and presses the respective spans 38a and 38b from the inner surface side to apply the belt thrust, the space between both spans 38a and 38b of the belt 38 is provided. The tension pulleys 78 and 81 can be arranged using the dead space, and the transmission A can be made compact. Moreover, since the inclination angle θ3 of the side surface of each tension pulley 78, 81 matches the cross-sectional angle of the pulley grooves 31, 36 of the speed change pulleys 28, 33, the tension pulleys 78, 81 are pulleys of the speed change pulleys 28, 33. Even if it moves into the grooves 31 and 36, it does not interfere with the side surfaces of the pulley grooves 31 and 36, and the tension pulleys 78 and 81 having a large outer diameter are used to change the bending ratio of the spans 38a and 38b of the belt 38. While making it smaller, shorten the distance between the two rotating shafts 2 and 12,
It is possible to make the transmission A compact in the axial direction between the rotary shafts 2 and 12.

The positions of the tension pulleys 78 and 81 are irrespective of the axial movement of the belt 38 due to the gear shift,
Since the outer surfaces of the tension pulleys 78, 81 are always in contact with a part of the inner surface of the belt 38 and can press it, the width of the tension pulleys 78, 81 is equal to the width of the belt 3 as described above.
8 is smaller than the width of the inner surface, and the belt 38 moves axially along the side surface of the pulley grooves 31, 36 on the side of the fixed sheaves 29, 34 while the winding diameter is changed by opening and closing the speed change pulleys 28, 33. Even tension pulleys 78, 8
1 does not deviate from the position of the belt 38 in the axial direction so that the loose side spans 38a and 38b cannot be pressed.
8 can be pressed stably.

Further, the tension pulleys 78, 81
Is made of a fiber reinforced resin mixed with polyamide fibers, wear of the block V-belt 38 due to contact with the tension pulleys 78, 81 can be reduced, and the blocks 40, 40, ... Even if the block belt 38 is on, each block 4
It is possible to reduce the hitting sound when 0 comes into contact with the tension pulleys 78 and 81 intermittently, and to reduce noise.

First speed change pulley 28 of speed change pulley mechanism 27
Since the boss portion 30a of the movable sheave 30 is subjected to high surface pressure by the torque cam mechanism 42, the boss portion 30a and the sheave body 30b are forged instead of being cast.
Since and are integrally formed, compared with the case where both are separately manufactured and then welded to be integrated, the roundness of the movable sheave 30 can be improved by eliminating welding distortion, and high load transmission can be achieved. The runout of the V-belt 38 that is performed can be reduced, its wear can be suppressed, and reliability can be improved.

Movable sheave 30 of the first transmission pulley 28
A torque cam mechanism 42 is provided between the boss portion 30a of the first rotating shaft 2 and the pulley shaft portion 4 of the first rotating shaft 2, and the torque cam holes 45 of the torque cam mechanism 42 are provided with forward and backward cam surfaces 45a and 45b. Since they are respectively formed, the movable sheaves 30 and 35 can be axially moved by the torque cam mechanism 42 to increase the belt thrust not only when the vehicle moves forward but also when the vehicle moves backward.

At this time, on the forward side, the pulley ratio of the speed change pulley mechanism 27 is in the Lo state in which the belt winding diameter of the first speed change pulley 28 is smaller than that of the second speed change pulley 33.
The belt thrust difference between the driving side pulley and the driven side pulley becomes large, while the pulley ratio of the speed change pulley mechanism 27 becomes Hi on the reverse side.
In this state, the belt thrust difference between the drive side driven pulley 28 and the driven side pulley 33 becomes small, but the lead angle θ1 of the forward cam surface 45a in each torque cam hole 45 is larger than the lead angle θ2 of the reverse cam surface 45b. Therefore, it is possible to obtain an appropriate belt thrust force in accordance with the characteristics of the belt thrust force difference during forward and backward travels.

In addition, the torque pin 43 of the torque cam mechanism 42 is diametrically penetrated by the pulley shaft portion 4 of the second rotary shaft 12, and the torque ring 44 is supported by the tip protrusions on both sides thereof. The verticality of 43 itself can be increased, and it is possible to prevent one-sided contact of the torque ring 44 with the cam surfaces 45a and 45b of the torque cam hole 45.

Further, the pinions 21, 21, ... In the planetary gear mechanism 19 are output gears 22 on the second rotary shaft 12.
Since the output gear 22 is drivingly coupled to the drive wheels, the output gear 22 can also be used as a pinion carrier to reduce the number of parts, and the pinion carrier as an output portion can be mounted on the second rotary shaft 12. The length of the second rotating shaft 12 can be shortened as compared with the case of being connected to the drive wheel side, and the continuously variable transmission A can be made compact in the axial direction.

Further, the casing 1 of the continuously variable transmission A is divided into three first to third divided casings 1a, 1b and 1c, and the first and second rotating shafts 2 and 12 are respectively first and second. Gear shaft portions 3 and 13 located between the split casings 1a and 1b, and second and third split casings 1b and 1
It is divided into two parts in the axial direction into the pulley shaft parts 4 and 14 located between c, the planetary gear mechanism 19 and the gear 5 on the gear shaft parts 3 and 13, and the speed change pulley mechanism 27 on the pulley shaft parts 4 and 14.
Are arranged respectively, the continuously variable transmission A can be divided into two by unitizing each arrangement portion of the transmission pulley mechanism 27 and the planetary gear mechanism 19. Therefore, when inspecting or repairing, for example, the belt 38 of the speed change pulley mechanism 27 or exchanging parts of the planetary gear mechanism 19, the remaining parts of both units may be left as they are and only the necessary side unit may be removed and disassembled. , Maintenance and inspection of parts and steel pipes can be performed easily.

A sleeve 8 is provided on the side of the gear shaft 3 and a bush 9 is provided on the side opposite to the gear shaft 3 in the small diameter portion of the half portion of the pulley shaft portion 4 of the first rotary shaft 2 on the side of the speed change pulley mechanism 27.
Of the fixed sheave 29 of the first shift pulley 28 is supported on the sleeve 8 and the bush 9 is supported by the third split casing 1c via the bearing 10. The sleeve 8 as a supporting portion is separated from a bush 9 for supporting the bearing 10. Therefore, when an axial load is applied to the fixed sheave 29 from the V-belt 38, the fixed sheave 29 faces inward with the position of the bearing 10 serving as a fulcrum, that is, the outer peripheral edge of the sheave 29, as in the case of the non-separated structure. It is possible to prevent tilting toward the groove 31 side, and it is possible to suppress partial wear of the belt 38 and the fixed sheave 29.

Furthermore, as shown in FIG.
The torque pin 43 of the torque cam mechanism 42 on the rotating shaft 2
The sleeve 8 is externally fitted onto the pulley shaft portion 4 on which the fixed sheave 29 is mounted, and both the fixed and movable sheaves 29 and 30 of the first transmission pulley 28 are fitted and supported on the sleeve 8. As in the case where the pulley is directly keyed to the pulley shaft portion 4, the relative movement between the movable sheave 30 and the pulley shaft portion 4 of the first rotating shaft 2 by the action of the force from the belt 38 on the fixed and movable sheaves 29, 30. The rotation is not impaired, and the movable sheave 30 and the pulley shaft portion 4 of the first rotary shaft 2 can be relatively rotated while the belt thrust is obtained by both sheaves 29 and 30, and the operation of the torque cam mechanism 42 is favorably performed. Can be secured.

Moreover, since the torque cam mechanism 42 is provided on the first speed change pulley 28 side that is the driven side of the circulating power when the continuously variable transmission A is in the forward drive state, the forward cam surface 45a of the torque cam hole 45 is provided. Even if the lead angle θ1 is constant, the required belt thrust force according to the pulley ratio can be easily taken out.

The movable sheave 3 of the first speed change pulley 28
A cylindrical collar 51 is fitted on the boss portion 30a of No. 0 so as to cover each torque cam hole 45, and a bearing 49 is mounted thereon.
Since the rotating cam 48 of the first cam mechanism 47 is supported via the, the torque cam hole 45 of the torque cam mechanism 42 can be sealed with the collar 51, and the lubricating oil filled in the torque cam hole 45 is exposed to the outside. Can be effectively prevented.

In the above embodiment, the ring gear 23 of the planetary gear mechanism 19 is connected to the first rotating shaft 2, but the gear 22 as a pinion carrier is connected to the first rotating shaft 2 to connect the ring gear 23. It may be an output gear. In addition, the sun gear 20 may be used as an output unit. In short, one of the sun gear 20, the pinion carrier, and the ring gear 23 of the planetary gear mechanism 19 is the first rotating shaft 2, and the one is the second rotating shaft 12. It may be connected and the rest may be used as an output unit.

Furthermore, it is possible to use the pinion carrier of the planetary gear mechanism 19 as the power input section and the first rotary shaft 2 as the output section.

Further, in the above embodiment, the circulatory power is transmitted to the speed change pulley mechanism 27 when the vehicle moves forward. However, when the frequency of use of the vehicle in the reverse is higher than that in the forward, the reverse drive is performed. Circulating power may be applied to the belt 38 in this state.

[0089]

As described above, according to the invention of claim 1, the speed change pulley mechanism and the differential gear mechanism having the first to third gear elements are arranged in combination between the pair of rotary shafts. With respect to the continuously variable transmission in which the first and second gear elements of the differential gear mechanism are drivingly connected to the respective rotary shafts, the movable sheave is opposed to the rear side of the movable sheave of each shift pulley in the shift pulley mechanism. A pair of drive mechanisms are provided to make the fixed sheave contact and separate between the two speed change pulleys in opposite directions, and the switching operation section is operated so that the belt winding diameters of the two speed change pulleys change in opposite directions. By providing an interlocking mechanism for interlocking both drive mechanisms with each other to change the pulley ratio, one of the rotating shafts or one of the third gear elements of the differential gear mechanism is used as an input section, and the other is used as an output section. Output section by switching operation The input section is switched to the normal rotation state, the neutral state or the reverse rotation state to change the speed, and the thrust balance of the belt between the two speed change pulleys makes it possible to adjust the movement to the neutral state. On the side of high frequency of use, the frequency of the large drive power applied to the belt in the speed change pulley mechanism is increased by setting the speed change pulley mechanism side of the power transmission path from the input section to the output section as the circulating power path. It is possible to easily obtain the forward / reverse rotation state of the continuously variable transmission without requiring the forward / reverse rotation mechanism while lowering the load on the belt to reduce the load on the belt.

According to the second aspect of the present invention, the movable sheaves of the two speed change pulleys are opposite to the fixed sheave, and the drive mechanism is rotatably supported on the boss portion of the movable sheave via bearings. And a fixed cam that comes into cam contact with the rotating cam. A cam surface is formed on one of the rotating cam and the fixed cam, while the other is used as a cam follower. In addition, the movable sheave is moved in the axial direction by relative rotation of the fixed cam and the shift changeover mechanism has one link connecting the two rotary cams to each other. Due to the thrust balance of the belt between the two speed change pulleys, the resistance at the time of shifting to the neutral state becomes small, and it is smoothly adjusted to the neutral state,
It is possible to stably maintain the neutral state.

According to the third aspect of the present invention, the frequently used side is set to the forward traveling side which is higher than the frequency during the backward traveling in the traveling state of the vehicle, so that the continuously variable transmission is in the normal rotation state or the reverse rotation state. Can be appropriately adapted to the traveling mode of the vehicle.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an overall configuration of a continuously variable transmission according to an embodiment of the present invention.

FIG. 2 is a front view showing the structure of a speed change pulley mechanism in the continuously variable transmission.

FIG. 3 is an enlarged cross-sectional view showing a structure around a first pulley of the transmission pulley mechanism.

FIG. 4 is an enlarged cross-sectional view showing a structure around a second pulley of the speed change pulley mechanism.

FIG. 5 is an enlarged cross-sectional view showing a structure around a differential gear mechanism.

FIG. 6 is an enlarged cross-sectional view of a movable sheave of the first transmission pulley.

FIG. 7 is an enlarged front view of a movable sheave.

FIG. 8 is an enlarged front view of a torque cam groove.

FIG. 9 is an enlarged plan view showing a link of the interlocking mechanism.

FIG. 10 is an enlarged cross-sectional view showing a state in which a spring is attached to the first tension arm.

FIG. 11 is a sectional view of a tension pulley of the tension mechanism.

FIG. 12 is a front view of a tension pulley of the tension mechanism.

FIG. 13 is a plan view showing a drive connection state of the continuously variable transmission with respect to the engine.

FIG. 14 is a front view showing a drive connection state of the continuously variable transmission with respect to the engine.

FIG. 15 is a diagram schematically showing a connecting structure of an interlocking mechanism and an operation lever.

[Explanation of symbols]

 A continuously variable transmission 1 casing 2 first rotary shaft 8 sleeve 9 bush 12 second rotary shaft 19 planetary gear mechanism (differential gear mechanism) 20 sun gear (second gear element) 22 output gear (third gear element) 23 ring gear (First gear element) 27 speed change pulley mechanism 28, 33 speed change pulley 29, 34 fixed sheave 30, 35 movable sheave 30a, 35a boss portion 31, 36 pulley groove 38 block V belt 38a, 38b span 42 torque cam mechanism 45 torque cam hole 45a Forward cam surface 45b Reverse cam surface θ1, θ2 Lead angle 47,52 Cam mechanism (drive mechanism) 48,56 Rotating cam 48a, 56a Cam surface 51,58 Fixed cam 52,59 Roller 62 Link 64 Linkage mechanism 66 Operation Lever (switching operation part) 68 Dead band part 69 Pin member 70 Engagement part 7 Tension mechanism 75 and 76 tension arm 78 and 81 tension pulley 83 tension spring 97 tension clutch 98 limit switch E engine

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaka Furukawa 3-15-15 Meiwa Dori, Hyogo-ku, Kobe, Hyogo Prefecture Bando Kagaku Co., Ltd.

Claims (3)

[Claims] 1. A first and a second rotating shafts arranged in parallel with each other, and a pair of speed change pulleys, wherein a fixed sheave and a movable sheave are arranged and supported on the respective rotating shafts so as to be opposite to each other. A belt wound between the speed change pulleys and a rear side of the movable sheave of each speed change pulley, and the movable sheave is brought into contact with and separated from a fixed sheave facing each other, and a belt winding diameter of the speed change pulley. A pair of drive mechanisms that change the drive ratio, a linkage mechanism that links the drive mechanisms so that the belt winding diameters of the speed change pulleys change in opposite directions, and changes the pulley ratio between the pulleys. Press the slack side span of the belt between the speed change pulley and the switching operation part that operates the mechanism so that the tension on the slack side span is greater than the tension generated corresponding to the pulley ratio between the pulleys. Belt thrust A tensioning mechanism for generating, a speed change pulley mechanism for drivingly connecting both rotary shafts in a variable speed manner, and first to third gear elements connected to each other, wherein the first gear element is connected to the first rotary shaft. On the other hand, a second gear element is connected to the second rotating shaft, and a differential gear mechanism is connected to the second rotating shaft. One of the first rotating shaft and the third gear element serves as an input unit, and the other serves as an output unit. It is configured such that the output section is switched to the forward rotation state, the neutral state or the reverse rotation state with respect to the input section by the switching operation of the switching operation section to perform the speed change, and the speed change between the both speed change pulleys in the speed change pulley mechanism is performed. It is possible to adjust the movement to the neutral state by the thrust force balance of the belt. In the forward rotation state or the reverse rotation state, the rotation speed of the first gear element is higher than the rotation speed of the second gear element on the frequently used side. The gear ratio of the differential gear mechanism and the differential gear mechanism is set to be higher continuously variable transmission according to claim. 2. The continuously variable transmission according to claim 1, wherein in the speed change pulley mechanism, the movable sheaves of both speed change pulleys are opposite to each other, and the drive mechanism is a cam mechanism. The mechanism has a cylindrical rotation cam rotatably supported on a boss portion of the movable sheave of the speed change pulley via a bearing, and a fixed cam that comes into cam contact with the rotation cam. One of the fixed cams has a cam surface, while the other is a cam follower that contacts the cam surface, and is configured to move the movable sheave in the axial direction by rotation and relative rotation of the fixed cam. The continuously variable transmission, wherein the speed change mechanism has one link connecting the rotating cams of the both cam mechanisms. 3. The continuously variable transmission according to claim 1, wherein the input portion is drivingly connected to an engine mounted on the vehicle, while the output portion is drivingly connected to driving wheels of the vehicle. A continuously variable transmission characterized in that the side that is frequently used is the forward side that rotates the drive wheels so that the vehicle travels forward.