JP3470237B2 - Agricultural work machine transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed change device for an agricultural work machine such as a management machine that is equipped with a rotary work machine and performs plowing work.

[0002]

2. Description of the Related Art Conventionally, there is a technique of using a ball clutch to shift gears without interrupting power transmission, that is, without a clutch. A movable cam is attached to one side of a shifter shaft having a projection for engaging the ball clutch. The movable cam is mounted on the other side of the shifter shaft by pressing the shifter shaft to one side to press the cam faces against each other while mounting and making the surface contact with the fixed cam supported on the mission case side. The shifter shaft is moved in the axial direction by displacing it by operating the operation wire.

[0003]

However, in the above, since the shifter shaft is moved by the surface contact between the cams, the contact resistance is large, and the compression spring for urging the shifter shaft to one side is provided. By using this, the shifter shaft is moved to one side against this compression spring, so a large operating force is required as a whole, and the operation of the shift lever becomes heavy,
There is a problem that the operability is bad.

A main object of the present invention is to provide an agricultural work machine which has an advantage that a shifter shaft can be moved with a light operating force and a gear shift can be performed without a clutch, and the gear shift operability can be further improved. The point is to provide a transmission.

[0005]

In order to achieve the above-mentioned object, the invention according to claim 1 is capable of engaging and disengaging a plurality of transmission gears via a ball clutch, as clearly shown in FIG. 5 or 9. A shifter for an agricultural work machine, comprising: a shift shaft having a hollow hole and a shifter shaft movably inserted into the hollow hole and having a projection for engaging the ball clutch. Is arranged around the axis of
A cylindrical fixed cam having a cam groove on its cylindrical surface is provided, and the shifter shaft is provided with a moving operation body having a roller that slides in the cam groove.

The invention according to claim 2 is the same as that according to claim 1, in order to make the operating load substantially constant over the entire operating range, as clearly shown in FIG.
The moving operation body has a wire guide for connecting the operation wire by bending it in an arc shape.

The invention according to claim 3 achieves the above main object with a different structure. As clearly shown in FIG. 10, a plurality of speed change gears are rotatably supported by a ball clutch. In a transmission device of an agricultural work machine comprising a speed change shaft having a hollow hole and a shifter shaft movably inserted into the hollow hole and having a projection for engaging the ball clutch, the shifter shaft is arranged in the axial direction. An end portion of a pair of operation wires that reversibly move forward and backward is coupled to the displaced position, and a circular rotating body that guides the middle portion of the operation wire by bending it in an arc shape is used as the shifter shaft. It is characterized by being equipped near the.

The invention according to claim 4 achieves the above-mentioned main object with a further different configuration. As clearly shown in FIGS. 11 and 12, a plurality of transmission gears can be engaged and disengaged via a ball clutch. In a transmission device for an agricultural machine equipped with a shaft support, a speed change shaft having a hollow hole, and a shifter shaft movably inserted into the hollow hole and having a projection for engaging the ball clutch, the shifter shaft is A movable cam plate having a plurality of rollers that rotate around an axis orthogonal to the axis of the shifter shaft, and having a multi-step surface for moving the shifter shaft in the axial direction between the rollers facing each other. It is characterized by being held.

[0009]

According to the first aspect of the invention, the shifter shaft is moved in the axial direction by the roller provided in the moving operation body sliding inside the cam groove of the cylindrical fixed cam. Along with this, the protrusion moves, the ball clutch engages, and power is transmitted from the shift gear to the shift shaft. The shifter shaft is moved by sliding contact between the roller and the cam groove,
Further, since the roller is held in the cam groove, the free movement of the shifter shaft in the axial direction can be restricted even if the conventionally required spring for pressing the cam surfaces against each other is eliminated. It is possible to reduce the operation load required for moving.

According to the second aspect of the present invention, since the operation wire follows the arc of the wire guide, the load applied to the operation wire is substantially constant regardless of the moving position of the moving operation body, that is, the entire operation range. can do.

According to the third aspect of the invention, when one of the pair of operation wires is on the forward side and the other is on the return side, the position of the shifter shaft is specified by the pair of operation wires. Therefore, even if the compression spring that urges the shifter shaft to one side, which is conventionally required, is abolished, the free movement of the shifter shaft in the axial direction can be restricted. In this state, the shifter shaft can be moved to a predetermined position. You can Further, since the middle part of each operation wire is guided in an arc shape along the circular rotating body, the movement of each operation wire becomes smooth, and the operation load can be made substantially constant over the entire operation range.

According to the fourth aspect of the invention, the shifter shaft moves in the axial direction by rolling the multistage surface of the movable cam plate while the roller holds the movable cam plate. The shifter shaft is moved by sliding contact between the roller and the movable cam plate, and because the roller holds the movable cam plate, the shifter shaft is free to move even if the conventional compression spring is abolished. The movement of the shifter shaft can be restricted, and the operation load required to move the shifter shaft can be reduced as a whole.

[0013]

1 and 2, 1 is an engine, 2 is an engine base, 3 is a mission case, 4 is a transmission case for transmitting the power of the engine 1 to the mission case 3, and 5 is an axle extending from the mission case 3, 6 is a pair of left and right traveling wheels mounted on the axle 5, 7 is a hitch for mounting a rotary working machine, 8 is a handle base mounted on the upper part of the transmission case 3, 9 is a steering handle, 10 is a main gear shift lever, 11 is a sub gear shift A lever, 12 is an operation lever of the main clutch for turning on and off transmission of power in the transmission case 4, 13
Is a pair of left and right side clutch operation levers for turning on and off the transmission of power to the axle 5 in the mission case 3.

As shown in FIGS. 3 and 4, the mission case 3 has an input pulley 1 for inputting the power of the engine 1.
5, PT for extracting power to the main transmission gear 19 and the working machine side
An input shaft 21 provided with an O output shaft 20 and a shift fork 2
Fork shaft 23 for sliding the main transmission gear 19 through
And a counter shaft 25 provided with the reverse gear 24 and a main transmission shaft 28 provided with the first speed gear 26 and the second speed gear 27. The first speed gear 26 is supported by the main transmission shaft 28 as an idle shaft, and the counter shaft 25 is rotated by the counter gears 29 and 30.
Is linked to. The counter shaft 25 is the counter gear 3
The main transmission shaft 28 is interlocked via 1, 32. In this way, the main transmission mechanism 33 having two forward gears and one reverse gear is configured, and the first forward gear is represented by reference numerals 21, 19, 26, 29, 3 and 3.
0, 25, 31, 32, 28 in the order of forward second speed is code 2
In the order of 1, 19, 27, and 28, the reverse code is 21, 19,
Power is transmitted in the order of 24, 25, 31, 32, and 28, respectively. In FIG. 3, reference numeral 34 denotes a shift arm that interlocks the fork shaft 23 and the main shift lever 10. Further, 67 is a side clutch arm that is interlocked with the operation lever 13 of the side clutch via the operation wire 68, and a pair of this arm 67 is provided on both left and right sides of the mission case 3.

Further, as shown in FIG. 5, the mission case 3 pivotally supports a sub-transmission shaft 41 that transmits power to the axle 5 via a sprocket 48a and a chain 48b. On the sub-transmission shaft 41, 3 rows of ball clutches 35,3
6 and 37, a low speed gear 38, a medium speed gear 39, and a high speed gear 40, which are constantly meshed with the low speed output gear 42, the medium speed output gear 43, and the high speed output gear 44 provided on the main transmission shaft 28 side, respectively. It is pivotally supported freely. A shifter shaft 45 is inserted in the sub-transmission shaft 41 so as to be movable in the axial length direction (hereinafter referred to as the axial direction), and each of the ball clutches 35, 36, 37 is selectively attached to the shifter shaft 45. Projection 46 to be engaged with
The cylindrical sleeve 46a having the above is joined by the pins 46d together with the collars 46b and 46c at both ends thereof.
In this way, the protrusion 46 is displaced by following the shifter shaft 45 in the axial direction, and the low, medium, and high speed gears 38 to 40 are selectively engaged with the auxiliary transmission shaft 41 via one of the ball clutches 35 to 37. The sub-transmission mechanism 47 having three stages of low speed, medium speed, and high speed is constrained to be combined.

In the above structure, as shown in FIGS. 3 and 5, the shifter shaft 45 is arranged around the axis of the shifter shaft 45.
Of the transmission case 3 through which one end of the low speed flat portion A, the middle flat portion C,
A high-speed flat portion E, and a taper portion B connecting between the flat portions,
Cylindrical fixed cam 4 provided with a total of three cam grooves 49a having D
Fix 9 Also, at the protruding end of the shifter shaft 45, three rollers 50a that project into the inside of each cam groove 49a and slide in the groove 49a, a shaft 50b that supports these rollers 50a, and each shaft 50b. A moving operation body (hereinafter, referred to as a shifter shaft moving operation body) 50 having a boss 50c for holding the base portion of is attached by a screw 52 and a nut 53 via the boss 50c.

Further, a wire guide 60 having a V-shaped wire insertion groove 61 is arranged on the outer peripheral portion of the cylindrical fixed cam 49, and the wire guide 60 and the shifter shaft moving operation body 50 are arranged.
Between the outer end of each shaft 50b in the pin body 6
Combine at 2. Then, the wire guide 60 is provided with a pair of operation wires 55, 550 extending from the auxiliary transmission lever 11.
Along the arc shape, in other words, curved in the arc shape, and the ends are connected by the pins 63 and 64.

As shown in FIGS. 6 and 7, the auxiliary speed change lever 11 for operating the operation wires 55, 550 is supported by a bracket 90 fixed to the steering handle 9 via a support shaft 91. By the one-way rotation transmission mechanism such as a one-way clutch built in the support shaft 91, the auxiliary transmission lever 1
In one swing motion of one stroke, the inner shaft portions 91a and 91b protruding at both ends of the support shaft 91 and the pair of cam plates 92 and 93 fixed to the inner shaft portions 91a and 91b are rotated by a predetermined angle, and the respective cam plates 92 and 93 are rotated. The rocking arms 96 and 97 that pivotally support the rollers 94 and 95 that come into contact with the outer peripheral portions of the rocking arms are rocked around the rocking shafts 98 and 99, and the coil springs 56 and 560 are attached to the ends of the rocking arms 96 and 97. Each operation wire 5 to be connected via
The inner and outer 55a and 550a of the 5,550 are operated to move forward and backward.

Each cam plate 92, 93 has a ridge portion 92 on the major axis side.
a and 93a are provided with troughs 92b and 93b on the minor axis side, and one major axis is made to coincide with the other minor axis.
The cam plate 9 on one side is arranged to be displaced by 0 degree.
When the second valley portion 92b is in contact with the roller 94 and is in a position in which the contact position is gradually changed toward the mountain portion 92a by operating the auxiliary shift lever 11, the mountain of the cam plate 93 on the other side is formed. The portion 93a is in contact with the roller 95, and is in a position in which the contact position is gradually changed toward the valley portion 93b side by operating the auxiliary shift lever 11.

In FIG. 6, reference numeral 81 is the operation wire 5.
The outer shell supports the outer shells 55b and 550b of the 5,550, and is fixed to the left and right connecting bars 80 of the steering handlebar 9. Reference numerals 82 and 83 are lever swing angle positioning holes provided in the cam plates 92 and 93, and are adapted to engage with a ball-insertion type positioner 84. Reference numeral 85 is a gear position indicating piece that projects from the upper end of one swing arm 97. Further, in FIG. 7, reference numeral 86 is a return spring of the sub-transmission lever 11, and 87 and 88 are stoppers that regulate the rocking dead center of the sub-transmission lever 11.

In this way, when the one operation wire 55 is operated in the pulling direction by the swing operation of the auxiliary transmission lever 11, the other operation wire 550 is operated in the loosening direction,
By such reversible forward and backward movements, the shifter shaft moving operation body 50 shown in FIG. 3 is rotated clockwise and counterclockwise, and the outer operation body 50 is moved to the cam groove 49a shown in FIG. The shifter shaft 45 is moved along with the forward and backward movements.

By the way, in FIG. 5, each operation wire 5
Outer 55b, 550 on the working end side of 5,550
b is an outer holder 5 supported on the mission case 3 side
7, when one of the inner 55a, 550a is on the pulling operation side, one side is higher in the height direction of the cylindrical fixed cam 49 so that a tensile load can be applied from the front side in the advancing direction of the cam groove 49a. The other side is supported on the lower side. Further, in FIGS. 3 and 5, one side portion 57a of the outer support 57 that supports the outer 55b on the higher side is bent so as to cover the mission case 3 side slightly, and the outer 550b that supports the outer 550b on the lower side is supported. The other side portion 57b of the bridge 57 is bent in the opposite direction. Thus, the load is satisfactorily transmitted to the wire guide 60 side during the pulling operation of each inner 55a, 550a due to the change in the vertical support position of each wire 55, 550 relative to the outer receiver 57 and the difference in the warp direction.

FIGS. 8 and 9 show a second embodiment in which two sets of cam grooves 49a and rollers 50a are provided, and the wire guides 60 are not provided, and the shafts 50b are fitted into the outer ends thereof. Each operation wire 5 directly through the connecting piece 600
It is a combination of 5,550.

FIG. 10 shows a third embodiment of the shifter shaft 4.
5, the pair of operation wires 5 described above reversibly moved forward and backward by the auxiliary speed change lever 11.
Each inner 55a, 550a of 5, 550 is axially displaced and coupled via each coupling piece 700, and has a wire insertion groove 70a composed of a V-shaped groove in the vicinity thereof.
A circular rotary body 70 is disposed which guides the inner parts 55a and 550a along the arc shape, in other words, curved and curved in the arc shape, and the bracket 570 which supports the circular rotary body 70 on the mission case 3. It is supported by the rotary shaft 70b.

11 and 12 show a fourth embodiment,
The shifter shaft 45 is provided with a pair of rollers 71, 72 that rotate around an axis orthogonal to the axis of the shifter shaft 45.
The rollers 71 and 72, which are supported via a and 72a and have a predetermined thickness, connect the low-speed flat portion A, the middle flat portion C, the high-speed flat portion E, and the flat portions. A movable cam plate 73 having two sets of tapered portions B and D is held between them. The rotating cam plate 73 is supported by a rotating shaft 74 protruding from the mission case 3 side, and the back surface of the rotating cam plate 73 is in contact with the thrust support seat 75. The operation wires 55, 550 are connected to the connecting pieces 76,
It is connected via 77. The operation wire 5 on one side
5 or 550 may be omitted, and instead, a compression spring such as a coil spring may be interposed. In this case, only one operation wire is provided, and the structure can be simplified.

[0026]

According to the first aspect of the present invention, the shift operation of the shifter shaft for performing the shift can be performed while the shift operation is performed by using the ball clutch and the non-clutch shift. Since it is performed by sliding contact with the cam groove provided in the fixed cam and the conventional compression spring is not necessary, the operating force required to move the shifter shaft can be reduced and the gear shifting operability can be improved. it can.

According to the second aspect of the present invention, since the operation wire follows the arc shape along the wire guide, the load applied to the operation wire can be made substantially constant over the entire operation range.

According to the third aspect of the invention, the shifter shaft can be moved to a predetermined position while the free movement of the shifter shaft in the axial direction is restricted by the pair of operation wires. Is guided along the circular rotary body in an arc shape, the movement of each operation wire can be made smooth, the operation load can be reduced, and the load can be made substantially constant over the entire operation range.

According to the fourth aspect of the present invention, the operation load required to move the shifter shaft can be reduced by the roller and the movable cam plate held by the roller.

[Brief description of drawings]

FIG. 1 is a side view of an agricultural work machine equipped with a transmission according to the present invention.

FIG. 2 is a plan view of the agricultural working machine.

FIG. 3 is a side view of an essential part showing the first embodiment of the transmission.

FIG. 4 is an upper sectional view of the first embodiment.

FIG. 5 is a bottom cross-sectional view of the first embodiment.

FIG. 6 is a perspective view of a lever portion for operating the transmission.

FIG. 7 is a sectional view of the lever portion.

FIG. 8 is a side view of an essential part showing a second embodiment of the transmission.

FIG. 9 is a sectional view of a main part of the second embodiment.

FIG. 10 is a cross-sectional view of essential parts showing a third embodiment of the transmission.

FIG. 11 is a cross-sectional view of essential parts showing a fourth embodiment of the transmission.

FIG. 12 is a plan view of an essential part of the fourth embodiment.

[Explanation of symbols]

3; mission case, 41; transmission shaft (sub-transmission shaft), 3
5,36,37; ball clutch, 38,39,40;
Always meshing transmission gear, 45; shifter shaft, 46; protrusion, 4
9: Cylindrical fixed cam, 49a; Cam groove, 50; Shifter shaft moving operating body, 50a; Roller, 55,550; Operating wire, 60; Wire guide, 70; Circular rotating body, 71, 7
2; roller, 73; movable cam plate

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-10443 (JP, A) JP-A-5-149397 (JP, A) JP-A 62-2047 (JP, A) JP-A 61- 127949 (JP, A) Actually opened 56-37748 (JP, U) Actually opened 61-150633 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 63/18 F16H 3 / 083

Claims (4)

(57) [Claims] 1. A plurality of speed change gears via a ball clutch.
A transmission shaft that has a hollow hole,
It is movably inserted in the hole and engages the ball clutch.
In the transmission of agricultural machine equipped with a shifter shaft having a projection to be operated, it is arranged around the axis of the shifter shaft
And is equipped with a tubular fixed cam having a cam groove on the tubular surface ,
The shift device for an agricultural work machine, wherein the shifter shaft includes a moving operation body having a roller that slides in the cam groove . Wherein said moving operation body operating wire in an arc
The transmission device for an agricultural work machine according to claim 1, further comprising a wire guide that is bent and connected. 3. A plurality of speed change gears via a ball clutch.
A transmission shaft that has a hollow hole,
It is movably inserted in the hole and engages the ball clutch.
In the transmission of agricultural machine equipped with a shifter shaft having a projection to be operated, the shifter shaft is displaced in the axial direction
In position, <br/> end portions of the pair of operating wires that reversibly reciprocate is coupled, a circular rotational body to be guided by curved middle portion of the operation wire in an arc Said shifter
A gearbox for agricultural work machines, which is equipped near the shaft . 4. A plurality of speed change gears via a ball clutch.
A transmission shaft that has a hollow hole,
It is movably inserted in the hole and engages the ball clutch.
In the transmission of agricultural machine equipped with a shifter shaft having a projection to be operated, the shifter shaft Contact comprises a plurality of rollers which rotates about the axis orthogonal to the axis of the shifter shaft
Ri, between the rollers which face each other, the axis of the shifter shaft
Transmission of agricultural machines movable cam plate having a multi-stage surface to be moved in the long direction, characterized in that it is挾<br/> lifting.