JP2860972B2 - Continuously variable transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission belt
By changing the diameter of each pulley of the pair of variable pulleys,
A continuously variable transmission that changes the speed ratio between both pulleys
Things. 2. Description of the Related Art Conventionally, a continuously variable transmission in a rice transplanter has been known.
Uses a pulley type transmission, and this transmission
Is, for example, a pair of rotating shafts
A pair of variable pulleys (drive and driven pulleys)
Each pulley is rotatable integrally with the rotating shaft,
Fixed split pulley fixed immovably and rotating integrally with rotating shaft
Slidably supported between the fixed split pulley
Form V-shaped belt groove around which power transmission belt is wound
The movable split pulley is fixed.
Pull and pull on the split pulley (effective belt and groove)
Radius) to change the gear ratio between the two rotating shafts.
It is designed to switch between low speed state and high speed state
is there. By the way, in rice transplanters, when planting rice,
The ability to run rice at a constant speed and run at a constant speed is required
Is done. However, among the pulley type transmissions described above,
The movable split pulley of the pulley is driven in the axial direction by the spring force
When this structure is used in rice transplanters, the viscosity of mud
The underbody load changes according to the belt pulley bell
The gear ratio fluctuates due to cutting into the ditch, etc.
It is difficult to plant at a constant pitch. [0003] To solve these problems, the transmission ratio
Drive or slave so that the
Use a cam with a movable pulley or a movable split pulley for both pulleys.
The belt tension is controlled by tension.
Is given. For example, 57-1
Japanese Patent No. 64352 discloses a technique in which one of
Of the variable pulley to the movable split pulley and the other
Direction of movable split pulley to fixed split pulley in pulley
And the movable split pulleys on the back of each pulley.
To the rotating cam that can rotate around the rotation axis
Rotating cam that consists of a fixed cam that is connected and cannot rotate
The movable split pulley is fixed by the relative rotation of the fixed cam
And a cam mechanism to move the
Connecting the rotating cam of the cam mechanism with a rod and a transmission shaft
As a result, one of the movable split pulleys of the drive and driven pulleys
When approaching the fixed split pulley facing this, the other movable pulley
Up from the fixed split pulley facing it.
The rotating cams of the two cam mechanisms are rotated in cooperation with each other to
Change the effective radius of the pulley to the belt member
The gear ratio between the rotating shafts is changed. [0004] In this proposal,
The rotating cams of both cam mechanisms are connected so as to be interlocked with each other.
Therefore, the operation of the speed changeover mechanism is performed at the time of speed changeover between the two rotating shafts.
The movable split pulleys of the drive and driven pulleys are
Opening and closing in synchronization with the direction, opening and closing force between driving and driven pulleys
Can partially cancel each other, and change gears between both rotating shafts
Can be performed promptly with a small operating force. Only
Actually, the bearing that supports the rotating cam is a movable split
The desired effect is obtained from the contact with the tip of the boss
Not be able to respond quickly, for example in an emergency
There is no problem. That is, the movable split pulley
When receiving thrust from the belt hung on almost half
The direction in which the movable split pulley is tilted with respect to the rotation axis.
But the bearing that supports the rotating cam
Is in contact with the tip of the boss of the movable split pulley.
Is received by the bearing at its tip
Therefore, the above moment is large and the movable split pulley
Both pressure distributions in the axial direction with respect to the rotation shaft outer circumference of the boss inner circumference are
Concentrated with a large peak, the sliding resistance of the boss was large
It will be good. Therefore, the rotating cams of both cam mechanisms are connected to each other.
Take out the thrust generated by the belt of one cam mechanism and
Although it is used for belt thrust of the
Shift operation requires a large operating force due to high sliding resistance,
Smooth switching of gear ratio between both rotating shafts with small operation force
It is difficult to do. In addition, the rotating cam and the fixed cam are
Contact, the sliding resistance is large.
In both cases, the shift operation force is increased. Moreover, the cam
The surface resistance is large, so the wear is fast and the wear is large.
If this occurs, the positioning accuracy of the pulley will deteriorate and the sliding resistance will decrease.
Is further increased. Therefore, the sliding resistance of the cam is reduced.
Lubrication oil maintenance is essential to keep
This was cumbersome and practically unsatisfactory. Further
In addition, since the fixed cam is fixed to the fuselage,
Difficult to adjust relative to fixed cam. In addition, the vibration of the variable pulley
When the dynamic system is different, the vibration of the engine
The transmission is transmitted to the transmission mechanism of the driven pulley, thereby
The pulley and the driven pulley behave differently, and the pulley opens and closes.
The gear ratio is not stabilized in a steady state, and as a result
Premature wear or belt wobble in the radial direction
There are problems such as increased heat generation and reduced durability.
You. The present invention has been made in view of such a point.
Of the above-mentioned cam mechanism and its movable split pulley.
By improving the connection structure, the operation of the transmission mechanism can be reduced.
Operation with smooth operation, and
The change in gear ratio due to movement is prevented by the cam mechanism.
To eliminate the disadvantages of increased operating force,
It is easy to adjust the relative relationship between the fixed cam and the rotating cam.
is there. [0005] The present invention has been made in consideration of the above-described problems.
In order to achieve the target, the following continuously variable transmission is provided.
Things. That is, a pair of parallelly arranged
Rotating shafts (24) and (29), and the rotating shafts (24) and (29)
Fixed so that it can be rotated integrally with it and cannot move in the axial direction
Split pulley (25a) (27a) and each rotating shaft (24)
The boss part (65) is rotatable and movable integrally with (29).
(68), the fixed pulley (25a) (2
7a) and a belt groove (25c) (27) having a V-shaped cross section.
From the movable split pulleys (25b) and (27b) forming c)
A pair of variable pulleys (25) and (27)
Between the belt grooves (25c) and (27c) of the ribs (25) and (27)
The transmission belt (26) wound around the
Moveable pulleys (25b) (27)
b) is moved toward and away from the fixed split pulleys (25a) and (27a).
And change the pulley diameter of the variable pulleys (25) and (27)
And a pair of cam mechanisms (A) and (B)
(25) Pulley diameters of (27) change in opposite directions
The two cam mechanisms (A) and (B) are linked to
Shift switching for changing the speed ratio between the turning shafts (24) and (29)
And each of the cam mechanisms (A)
(B) is a movable split pulley of the variable pulleys (25) and (27).
(25b) Boss (65) that rotates integrally with (27b)
(68) pivots on bearings (64) and (67)
Movable pulley side cam (42) (48) movably supported
And a rotating cam portion that comes into contact with the cams (42) and (48).
(43) and (44) for relative rotation of both rotating cams.
More movable split pulley (25b) (27b) is moved in the axial direction
In the configuration in which the movable split pulley (2
7b) and the bracket (51) provided with the boss (68)
A spring (50) is interposed in
The switching mechanism (C) is a flat mechanism orthogonal to the rotation axes (24) and (29).
Connecting members (43a) and (44a) extending substantially parallel to the surface;
The movable split pulley side cam of the cam mechanism of the other variable pulley
The movable split pulleys (25b) (2) of both cam mechanisms (A) and (B)
7b) are rotated around the rotation axes (24) and (29)
Connecting links (45), (47), (4)
And 6) a continuously variable transmission.
You. The speed ratio between the two rotating shafts (24) and (29) is switched.
Each pulley (25), each cam mechanism of (27)
(A) The rotating cams (43) and (44) in (B)
From one operating rod (45) and arms (46) (47)
Are connected so as to be interlocked with each other by a speed change mechanism (C).
Pulley (25) or cam mechanism of (27)
The rotating cams (43) and (44) of FIGS.
4) or (29), the movable split pulley
Pulley by cam contact with side cam (42) or (48)
(25) or (27) the movable split pulley (25b) or
When (27b) is moved in the axial direction, the other
Pulley (27b) or (25b) is one of the pulleys
Movable split pulley (25b) in (25) or (27)
Or (27b) fixed split pulley (25a) or (27b)
It moves with the operation opposite to the contact and separation operation to a), and
Of the two movable split pulleys (25b) and (27b) in the opposite direction
The gear ratio of both rotating shafts (24) and (29) is changed
Is done. An embodiment shown in the drawings will be described below.
First, the entire riding type rice transplanter will be described.
(1) is a passenger body, and a rear part of the passenger body (1)
The planting section (3) is connected via the lift mechanism (2).
You. The engine (5) is mounted on the body frame (4)
And there is a front wheel (6) below it. (7) is mi
Transmission case (8)
There is a rear wheel (9) at the rear end of the transmission case (8).
You. (10) is a driver's seat, (11) is a footrest, (1)
2) is a steering wheel. Lift mechanism (2)
Is the top link (13) of the link frame and Lowerlin
(14) is attached and the hydraulic cylinder expands and contracts.
To swing the links (13) and (14)
(3) to go up and down. Planting part (3) is seedling
Mounting platform (15), float (16), transmission case (17)
It consists of (18) is a rotary case
Yes, (19) shows a planting arm. [0008] The above-described transmission device will be described with reference to FIG.
To explain, pulley (20) and bell from engine (5)
The pulley (22) is driven via the
The amplifier (23) is driven. This hydraulic pump (23)
It sends hydraulic oil to the elevating part of the planting part. Pulley
A split pulley (25) is provided on the rotation shaft (24) of (22).
Has been cut, and it is now possible to split it through the belt (26).
(27) is driven. The split pulley (27) is also
Teeth in the transmission case (7) via the latch (28)
The car mechanism drives the rotating shaft (29) and the shaft (30). (3
0) is a planting drive shaft. Also, mission case (7)
The gear (31) driven by the internal gear mechanism is a propeller shaft
(32) to drive the differential gear mechanism (3
3) The front wheel (6) and the rear wheel (9) are driven via (34).
It is. (35) is the tooth in the transmission case (8) for rear wheel drive
2 shows a car mechanism. (36) and (37) are front and rear axles.
You. Next, a cam mechanism characterized by the present invention and its cam mechanism
Continuously variable transmission with improved connection structure for movable split pulley
To explain the arrangement, in FIG.
One of the fixed split pulleys (25)
a) is provided with a seedling connecting clutch (38), shown in FIG.
Do not use the seedling clutch lever provided on the operation column.
Forced release of fixed split pulley (25a) by operation
To position the bearing (39) on the rotating shaft (24)
The belt (26) can be dropped to stop the drive.
You. The fixed split pulley (25a) is pivoted by a spring (41).
The other movable split pulley (25b)
Is a rotation that rotates on a shaft (24) via a bearing (63).
It has a cam sliding surface (62) that engages with the moving cam (43).
The movable split pulley cam (42) supports
The movable split pulley side cam (42)
In both cases, the movable split pulley (25b) moves. And movable split
The bearing (6) is attached to the boss (65) of the pulley (25b).
4), the movable split pulley side cam (42) is supported and moved.
The moving cam is composed of a rotating cam.
(43) The movable split pulley side cam (42) is brought into contact with the
In addition, the bearing is smaller in diameter than the movable split pulley cam (42).
Integral with the boss (65) that is rotatable via the bush (64)
The rotating split pulley (25b) is arranged in the order of rotation.
You. Therefore, when the seedling clutch is not operating, the split
(25a) becomes a fixed split pulley,
Rotationally integrated with the shaft (24) and supported so that it cannot move in the axial direction
Around the fixed split pulley (25a) and rotating shaft (24)
At the boss (65) so that it can be rolled integrally and move in the axial direction
Supported, V-shaped cross section between fixed split pulley (25a)
Movable pulley (25) forming a belt groove (25c) of
b) constitutes a variable pulley. Above
Movable split pulley (25b) of variable pulley is fixed split pulley
(25a) to change the pulley diameter of the variable pulley
The cam mechanism is a movable split pulley side cam (42) and a rotating cam.
(43). On the other hand, the rotating shaft (29), which is the driven shaft,
Also, there is a rotating cam (44), and the rotating cam (43)
Both are the main clutch petals (independent of the seedling clutch
Operating tool) and an arm (46) of an operating rod (45) interlocked therewith
(47) and levers (43a) and (44a) are operated.
In this case, the arm (46) (47) and the lever (43a)
(44a) is rotatably connected with pins (71) and (72).
Is done. The cam is moved by the arms (46) and (47).
(43) and (44) rotate, but the shafts (24) and (29)
Does not move in the direction. The operating rod (45) is also provided with
Works together with Therefore, planting work using the lifting lever
Sometimes a gear change operation can be performed. To the rotating cam (44)
Movable split pulley side cam having sliding cam surface (70) to engage
(48) is one movable split pulley of the split pulley (27).
(27b) and a spring (50) receiving member (5
The boss (68) of 1) is supported via the bearing (67).
Have been. Then, the movable split pulley is placed on the rotating cam (44).
Contact the rear side (48), and further move the movable split pulley side cam.
(48) Boss smaller in diameter and rotatable via bearing
Variable split pulley (27b) that rotates integrally with the
It is location. A key is attached to the external fitting pipe (52) of the shaft (29).
(53) so that the pulley (27b)
It rotates integrally with (52). In addition, other than split pulley (27)
The pulley (27a) has a case cover (54).
And the main clutch (28)
Power is being transmitted to the case. Therefore, like a seedling clutch lever.
The split pulley (25a) is forcibly separated by a simple manual operation tool.
Operating in the direction, bearing (39) position on axis (24)
The belt (26) can be dropped to stop the drive.
However, on the other hand, the operating lever
By operating the rotating cams (43) and (44) via (45),
Power to the transmission case is cut off and the cam is moved to the low speed side.
Can be migrated. From the above,
Starting can always be performed from the low speed side. And Wari Pooh
Split pulley driven by transmission belt (26) from ri (25)
Ri (27) is connected to the main clutch (2) from the case cover (54).
Drive shaft (29) via 8). Therefore the rotation axis
Fixed split fixed to (29) via clutch (28)
The pulley (27a) and the rotating shaft (29) rotate integrally with each other.
Boss (69) movably in the axial direction and fixed
V-shaped belt groove (2) between the split pulley (27a)
7c) and a movable pulley (27b) forming a variable pulley.
Are configured. Also, the movable split pulley of this variable pulley
(27b) is moved toward and away from the fixed split pulley (27a).
The cam mechanism that changes the pulley diameter of the variable pulley
Integrated with pulley (27b) and spring (50)
On the boss (68) of the metal fitting (51) that rotates
Movable pulley rotatably supported via ring (67)
A revolving cam (48) and a rotating cam that comes into contact with the cam.
And a cam member (44). Rotating cam (4
4) is a cam sliding surface (70) in contact with the cam (48).
The arm (47) of the operating rod (45) cannot move in the axial direction.
Enabled and rotatable relative to the externally fitted pipe (52)
There is a bearing (66) so that In addition,
(50) is a movable split pulley (27b) and a metal fitting (5).
1) and rotate integrally, but transmission of vibration between variable pulleys
Can be suppressed. That is, the vibration of the variable pulley
When the system is different, the vibration of the engine
It is transmitted to the speed change mechanism of the dynamic pulley,
The pulley and the driven pulley behave differently, and the pulley opens and closes.
Speed ratio is not stable in a steady state, and as a result
Caused by premature wear or radial wobble of the belt
There is a problem that the amount of heat increases and the durability decreases.
However, if the above-mentioned spring (50) is used, both are acceptable.
Even if the vibration system of the variable pulley is different, both variable pulleys
Transmission of vibration between the members is suppressed by a spring (50).
It is possible to eliminate pulley opening and closing in steady state
The gear ratio can be maintained stably, so that the sliding part of the pulley
Wear can be suppressed and the belt pulley
To prevent excessive heat generation to reduce excessive heat generation and improve its durability
Can be achieved. By the way, the operating rod (45) and the arm
(46) and (47) are compatible with pulleys (25) and (27)
Adjust so that the pulley diameters of the changing pulleys change in opposite directions.
Mechanism (A) (B) in conjunction with both rotating shafts (24) (2)
9) The transmission gear ratio is variable, but arranged in parallel with each other.
Extending substantially parallel to a plane orthogonal to the rotating axes (24) and (29).
Levers (43a) and (44a)
The movable split pulley side cams rotate around the rotation shafts (24) and (29).
Arm (46) connected to rotate in conjunction with the arm
(47) a connecting link composed of an operating rod (45);
Constitute the speed changeover mechanism (c). Both times
When changing the gear ratio between the turning shafts (24) and (29), both
For each cam mechanism (A) (B) of the variable pulley (25) (27)
The rotating cams (43) and (44) in the
Interlocking is possible by the speed change mechanism (c) having two links
, One pulley (25) or (2)
7) The rotating cam (43) or (4) of the cam mechanism A or B
4) Rotate around the rotation axis (24) or (29)
With the movable split pulley side cam (42) or (48).
Movable split of pulley (25) or (27) by cam contact
When the tool (25b) or (27b) is moved in the axial direction,
The cam sliding surfaces (62) and (70) are formed in opposite directions.
The other pulley (27) or
The split pulley (27b) or (25b) of (25)
Movable split pulley (2) in pulley (25) or (27)
5b) or (27b) fixed split pulley (25a) or
(27a) moves with the opposite operation to the contact / separation operation
The opposite direction of the two movable split pulleys (25b) and (27b)
Gear ratio between both rotating shafts (24) and (29)
Is changed. That is, the movable split of the pulley (25)
Pull the pulley (25b) close to the fixed split pulley (25a).
And fix the movable split pulley (27b) of the pulley (27).
Pulley when separated from fixed pulley (27a)
Make the pulley diameter of (25) larger than the pulley (27)
This increases the rotation of the rotating shaft (24) to the rotating shaft (29).
Promptly transmit. On the other hand, movable pulley of pulley (25)
(25b) is separated from the fixed split pulley (25a),
And the movable split pulley (27b) of the pulley (27) is fixedly split.
Pulley (25) when approaching pulley (27a)
Of the pulley, and increase the diameter of the pulley (27).
By reducing the rotation of the rotating shaft (24),
Can be transmitted to the turning axis (29). A place like above
In this case, the opening / closing force between the variable pulleys (25) and (27) is reversed.
The opening and closing force between the pulleys (25) and (27) partially
The two cam mechanisms (A) and (B)
Link (45) (4)
6) It is connected at (47). And mosquito
The movable split pulley (25b) (2
7b) to drive the pulleys (25) and (27)
The load fluctuates due to the
Thus, the gear ratio can be kept constant even when the vehicle is driven. others
Therefore, the traveling speed of the rice transplanter is
Plant rice at a constant pitch, regardless of load
Can be. The rotating cam (43) and the movable split as described above
Wheel cam (42), rotating cam (44) and movable split pulley
Upper and lower overlapping cams such as the side cam (48)
The cam sliding surface of the split pulley operation cam (62)
In (70), when the cam is turned, a turning resistance is applied.
The operating force of the bars (43a) and (44a) increases. There
The cam sliding surface of the split pulley operation cam (62) (70)
Slide resistance by inserting a ball or thrust bearing into the sliding part
An operation force reducing device for reducing power consumption is provided. The one in Figure 2 is Bo
(55) provided on the sliding parts (62) (70)
To provide a tear groove (56) on one cam and a half on the other cam.
The figure provided with a spherical groove (57) is shown. As above
The sliding resistance is greatly reduced by providing
As a result, the gear ratio is maintained for a long period
Nonce can be made unnecessary. In any case, the speed changeover mechanism (c) is a single
Since it has a straight rod-shaped link,
Rotating cams (43) and (44) in cam mechanisms A and B
Can be connected with high rigidity, and the operating force is
Loss can be reduced. Also, the link is
The thrust of the other mechanism (A) or (B)
(B) or (A) can be transmitted efficiently,
The operating force can be reduced. From the above,
Ming is a pair of rotating shafts (24) arranged in parallel with each other.
(29) and the rotating shafts (24) and (29) are integrally rotated.
And a fixed split pulley (25
a) One rotation is applied to (27a) and each rotation axis (24) (29).
Boss (65) (68) movably supported by the body
Between the fixed pulleys (25a) and (27a)
Movable to form V-shaped belt grooves (25c) (27c)
A pair of variable pulleys composed of split pulleys (25b) and (27b)
(25) (27) and the variable pulleys (25) (27)
Between the belt grooves (25c) and (27c)
The moving belt (26) and each of the variable pulleys (25) (2)
7) The movable split pulley (25b) (27b)
(25a) (27a)
(25) A pair of cam machines for changing the pulley diameter of (27)
Structures (A) and (B) and both variable pulleys (25) and (27)
So that the diameters of the pulleys change in opposite directions.
By linking the mechanisms (A) and (B), both rotating shafts (24) (2)
9) a speed changeover mechanism (C) for changing the speed ratio between
Each of the cam mechanisms (A) and (B) is a variable pulley.
(25) The movable split pulley (25b) (27b) of (27)
Bearings on the bosses (65) (68) that rotate together with the
(64) and (67) rotatably supported via
Split pulley side cams (42) and (48) and the cams (42)
Rotating cam member (43) (44) that makes cam contact with (48)
And a movable split pulley by the relative rotation of the two rotary cams.
(25b) (27b) is configured to move in the axial direction
The movable split pulley (27b) and the boss portion
Spring between the metal fitting (51) provided with (68)
(50) and the speed changeover mechanism (C)
Is substantially parallel to a plane orthogonal to the rotation axes (24) and (29).
The extended connecting members (43a) (44a) and the other variable
With the movable split pulley side cam of the
(A) (B) movable split pulleys (25b) (27b)
Is rotated in cooperation with the rotation axes (24) and (29).
Connecting links (45), (47) and (46) for connecting to
It features a continuously variable transmission provided. According to the present invention, the movable split of the variable pulley is
To the fixed split pulley to separate the diameter of the variable pulley.
And a pair of variable pulleys
The two cam mechanisms are linked so that the diameter changes in the opposite direction.
And a speed changeover mechanism for changing the speed ratio between the two rotating shafts.
On the boss that is provided and rotates integrally with the movable split pulley.
Movable split pulley rotatably supported via an ring
Relative rotation between the cam and a rotary cam member that comes into contact with the cam
To move the movable split pulley in the axial direction
The movable split of each pulley is
Driving the pulley, that is, firmly setting the open / close position of the pulley
It can be fixed, so that even if load changes occur,
Gear ratio can be kept constant. Because of this
The traveling speed of the planting machine depends on the muddy state of the rice field,
No matter what, the rice can be planted at equal pitch
You. In both rotating shafts, a rotating cam, a movable split pulley
Since the side cam and variable split pulley are arranged in this order, the rotating cam
When the movable split pulley side cam is pushed from the outside by rotation of
In addition, the variable split pulley can be moved,
Is smooth, and a good belt shift can be performed. Further
The diameter of the movable split pulley cam is larger than that of the boss.
And operate the cam via the bearing.
Adopted to increase the cam contact area
To greatly reduce sliding resistance and reduce wear.
Even so, it was greatly improved. Furthermore, on both pulleys
Drive of the movable split pulley by the speed change mechanism
Between the driven and driven pulleys
The opening and closing force of the two pulleys is reversed.
Since they cancel each other, the operating force is light. Plus movable
The split pulley side cam bears around the boss of the movable split pulley.
Moving in the axial direction through the
The movable split pulley side cam and the rotation that comes into contact with it
The operating force is reduced by the relative rotation of the cam member.
Lighter weight, movable pulley cam and contact
The rotating cam member is not fixed to the
The adjustment of the engagement is easy, and a resistance reducing member is provided on the cam sliding part.
By using it, the operating force can be reduced and
The work is performed smoothly. Also, one of the gear changeover mechanism
Of the variable pulley cam mechanism
Rotating cams are connected with high rigidity to save operating force.
And the extraction thrust of one cam mechanism is applied to the other cam mechanism.
Transmission can be performed efficiently, greatly reducing the shifting operation force.
Emergency response can be taken quickly. In addition,
Vibration system of a pair of variable pulleys is different when using a pulling
Even in this case, transmission of vibration between a pair of
Can be suppressed by pulling, and in the steady state
The gear ratio can be stably maintained without opening and closing the pulley,
Prevents early wear of pulley sliding parts
To prevent excessive heat generation by preventing the belt from moving in the pulley radial direction.
And other effects such as improved durability
It plays a fruit.

[Brief description of the drawings] FIG. 1 is a sectional view of a transmission according to the present invention. FIGS. 2A and 2B are a plan view and a sectional view of a cam sliding portion. [Fig. 3] Overall view of rice transplanter FIG. 4 is an explanatory view of a transmission device. [Explanation of symbols] 7 Missions 24 Drive shaft (rotary shaft) 25% pulley (variable pulley) 26 belt 27 split pulley (variable pulley) 28 main clutch 29 Driven axis (rotary axis) 43 Rotating cam 44 Rotating cam 45 Operating rod 46 arm 47 arm 48 Movable split pulley side cam 50 spring 51 Bracket 64 bearing 65 Boss 67 bearing 68 Boss

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Nimonori Yamamoto               1-32 Chaya-cho, Kita-ku, Osaka-shi, Osaka               Ma Agricultural Machinery Co., Ltd.                (56) References: Japanese Utility Model, Sho 55-132544 JP, U)                 Shokai Sho 57-164352 (JP, U)                 Jiko 38-3213 (JP, Y1)

Claims (1)

(57) [Claims] A pair of rotating shafts (24) (2)
9) and a fixed split pulley (25a) fixed to the rotary shafts (24) and (29) so as to be rotatable integrally and immovable in the axial direction.
(27a) and the rotating shafts (24) and (29) are supported by the bosses (65) and (68) so as to be rotatable and movable integrally, and have a cross section V between the fixed pulleys (25a) and (27a). A pair of variable pulleys (25) and (27) including movable split pulleys (25b) and (27b) forming a U-shaped belt groove (25c) (27c), and the variable pulleys (25) and (27)
The transmission belt (26) wound between the belt grooves (25c) and (27c) of the variable pulley (25) (2c)
7) A pair of cam mechanisms (A) and (A) that change the pulley diameter of the variable pulleys (25) and (27) by moving the movable split pulleys (25b) and (27b) toward and away from the fixed split pulleys (25a) and (27a). B) and both variable pulleys (25) and (27)
The two cam mechanisms (A) and (B) are linked so that the diameters of the pulleys change in opposite directions.
9) a speed changeover mechanism (C) for making the speed change ratio variable between each of the cam mechanisms (A) and (B).
7) Swivel with the movable split pulley (25b) (27b)
Bearings (64) on the bosses (65) (68)
Movable split pulley rotatably supported via (67)
The cams (42) and (48) and the cams (42) and (48)
Rotating cam members (43) and (44) that come into contact with each other.
The movable split pulley (25b) (2
7b) that is configured to move in the axial direction
And a movable split pulley (27b) and a boss (68) are provided.
A spring (50) is interposed between the metal fitting (51) and the metal fitting (51).
In addition, the speed changeover mechanism (C) is connected to the rotating shafts (24) and (29).
A connecting member (43a) (4) extending substantially parallel to the orthogonal plane.
4a) and the movable split pulley of the other variable pulley cam mechanism
And the movable split pulley (2) of both cam mechanisms (A) and (B).
5b) (27b) around rotation axis (24) (29)
A link (45) for linking and pivoting connection
(47) A stepless variable characterized by having (46).
Speed device.