JPH10227341A - Tractor power transmission structure - Google Patents

Abstract

(57) [Problem] Conventionally, a tractor is provided with a plurality of transmissions of a traveling system in order to cope with various works. In addition, the tractor is provided with an external power take-off shaft for driving a work machine connected to the rear part, and also with a transmission for changing the coaxial rotation speed. For this reason, the mission case tends to be long before and after, and a compact and inexpensive tractor has been desired especially for small-scale farmers. A forward gear (15) and a reverse gear (61) are provided so as to freely rotate on one axis, and a sliding operation of a forward / reverse switching clutch (60) between the two gears (15) and (61) causes the two gears (15) to slide.
The forward / reverse switching device 16 is configured to transmit one of the rotational powers of the shaft 61 to the shaft 10, and the forward gear 15 is configured by a two-stage gear. The interlocked power take-off gear 14 was engaged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tractor power transmission structure.

[0002]

2. Description of the Related Art Conventionally, a tractor is provided with a plurality of transmissions of a traveling system in order to cope with various operations. In addition, the tractor is provided with an external power take-off shaft for driving a work machine connected to the rear part, and also with a transmission for changing the coaxial rotation speed. For this reason, the transmission case of the tractor tends to be long before and after, and a compact and inexpensive tractor has been desired especially for small-scale farmers.

[0003]

SUMMARY OF THE INVENTION The present invention proposes to solve the above-mentioned conventional problems, and has a tractor power transmission structure as follows. That is, a forward gear 15 that transmits the rotational power and constantly rotates, and a reverse gear 61 that constantly rotates reversely with respect to the forward gear 15 are provided on a traveling system drive shaft 10 that transmits the rotational power of the engine. A forward / reverse switching device 16 that transmits the rotational power of one of the two gears 15 and 61 to the drive shaft 10 by operating a clutch 60 that is provided idle and provided between the two gears 15 and 61, One of the gears of the forward / reverse switching device 16 is constituted by a two-stage gear, and a tractor power transmission structure is formed by meshing the power take-out gear 14 interlocked with the external power take-off shaft 29 from the gear.

[0004]

According to the power transmission structure of the tractor constructed as described above, one of the gears of the forward / reverse switching device 16 is constituted by a two-stage gear, and a power take-off gear interlocked with the external power take-off shaft 29 from the same gear. Since the gears 14 mesh with each other, the apparatus can be simplified and the cost of parts can be reduced as compared with a configuration in which a reduction gear or a shaft is separately provided for taking out external power and the rotational power is branched.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing the inside of the transmission case of the tractor. The rear end of the engine body of the tractor is connected to the clutch housing 2, and the rear end is further connected to a front bearing case 9 containing a forward / reverse switching device 16. Further, the tractor is provided with a front wheel speed increasing device 18 which can drive the peripheral speed of the front wheels higher than that of the rear wheels.

More specifically, a clutch shaft 12 for outputting rotational power is output from a rear wall portion 19 of the engine body.
A weight wheel 20 and a clutch disc 21 are pivotally supported on the clutch shaft 12, and a shifter ring 22 that slides back and forth on the clutch shaft 12 behind the disc 21 is provided. The clutch 1 is turned on and off by rotating the shifter arm shaft 23 on the side of the housing 2 by operating a clutch pedal or the like and moving the shifter arm 24 connected thereto forward and backward.

The connecting housing 8 connected to the rear part of the clutch housing 2 is made of sheet metal for covering a front bearing case 9 described later. The front end 25 is joined to the rear end face 26 of the clutch housing 2 to tighten bolts or the like. The rear end is similarly joined to and connected to the front end 27 of the front transmission case 7. A forward / reverse switching device 16 is provided in the front bearing case 9, and the rotational power input into the case from the clutch shaft 12 is used as the forward rotation of the traveling system.
Or, in reverse and output from the traveling drive shaft 10,
The power take-out drive shaft 11 is separately protruded to interlock the external power take-out shaft 29 at the rear of the vehicle body.

A drive gear 13 for transmitting the rotation of the clutch shaft 12 protrudes from an upper portion of the front bearing case 9 and a rear wall portion 1 of the clutch housing 2 is provided below the drive gear 13.
The traveling drive shaft 1 extends between the rear bearing 9 and the rear part of the front bearing case 9.
0 is pivotally supported. This traveling drive shaft 10
Is a two-stage gear 15 which always meshes with the drive gear 13 and idles, a back gear 61 which always rotates reversely with respect to the two-stage gear 15, and a two-stage gear 15 and the back gear 61
And a forward / reverse switching clutch 60 is provided.

The case 9 also includes a power take-out drive shaft 11 that constantly meshes with the rear gear of the two-stage gear 15 to transmit this rotational power to an external power take-out shaft 29 at the rear of the vehicle body.
An intermediate gear 62 that reverses the rotation of the coaxial 11 and returns the same to the traveling drive shaft 10 again is supported. That is, when the forward / reverse switching clutch 60 is moved forward,
The rotational power is transmitted to the drive gear 13, the two-stage gear 15, the forward / reverse switching clutch 60, and the traveling drive shaft 10. When the forward / reverse switching clutch 60 is moved rearward, the rotational power is transmitted from the driving gear 13, the second gear 15, the power take-off gear 14, the intermediate gear 62, the back gear 61, and the forward / reverse switching clutch 60.
Transmitted to the traveling drive shaft 10; Also, the rear end of the traveling drive shaft 10 is provided so as to protrude outside the case in a straight line,
The coupling 63 is connected to the transmission case input shaft 3, and the power take-off shaft 11 is similarly connected to the coupling 6.
4 to the connecting shaft 39.

The transmission case mainly comprises a front transmission case 7 containing a transmission, and a rear transmission case 31 containing a rear wheel differential 56, a power take-out transmission 30, and the like. , 31 are connected by fasteners such as bolts. The front transmission case 7 has an intermediate wall portion 32 formed at an intermediate portion, and front and rear ends thereof are formed to be open. At the rear end portion, a front wall portion 33 of the rear transmission case 31 is joined and closed. Configuration. Inside the case 7, a gear shaft 34 for inputting rotational power between the middle wall portion 32 and the front wall portion 33 of the rear transmission case 31, a main transmission shaft 36 for appropriately shifting the rotation of the gear shaft 34, An auxiliary transmission shaft 35 for further shifting the rotation of the main transmission shaft 36, and a front wheel take-out shaft 17 for branching the rotation of the auxiliary transmission shaft 35 to the front wheels are provided as bearings.

The front end surface 28 of the front transmission case 7 is
The front cover 37 is closed with a fastener such as a bolt, and a rear bearing case 38 is attached to the front of the front cover 37. The transmission case input shaft 3 bears across the rear bearing case 38 and the front cover 37, and the front part of the power take-out interlocking shaft 4 that transmits power to the external power take-out shaft 29 is supported by the front cover 37. The front end and the rear end of the connection shaft 39 supported by the rear bearing case 38 are connected by a coupling 40.

Further, the front cover 37 is provided with a front wheel speed increasing device 18 between the front wheel take-out shaft 17 supported by the front cover 37 and the connecting shaft 41 supported by the rear bearing case 38. The front wheel speed increasing device 18 includes a direct coupling clutch 42 that rotates integrally with the front wheel take-out shaft 17, and a counter shaft 43.
Speed increasing clutch 44 which rotates by increasing the speed through
Is provided to increase the peripheral speed of the front wheels relative to the peripheral speed of the rear wheels when the tractor turns by turning on either one of the clutches.

A gear shaft 34 and an auxiliary transmission shaft 35 are provided on an extension of the transmission case input shaft 3, and a front main transmission shaft 36 and a rear main transmission shaft 45 are rotatable around the power take-out interlocking shaft 4. , And the rear main transmission shaft 45 is supported by the middle wall portion 32 and the front wall portion 33 of the rear transmission case 31. Main transmission 5
The power transmission is switched by an axial movement of a pre-main-speed transmission clutch 46 or a post-main-speed transmission clutch 47 on the main transmission shaft 36. The input gear 48 at the rear end of the input shaft 3 and the main transmission shaft 36 When the drive gear 49 at the front end is engaged and constantly rotated to move the transmission clutch 46 before the main transmission forward, the power is transmitted to the gear shaft 3 by the engagement of the transmission gear 50.
Transmit to 4. When the transmission clutch 47 is moved forward after the main transmission, the power is transmitted to the gear shaft 34 by the engagement of the transmission gear 51. In addition, the transmission clutch 47 after the main transmission
When the gear is moved rearward, the power is transmitted to the gear shaft 34 by the engagement of the transmission gear 45. The auxiliary transmission 6 directly connects the auxiliary transmission gear 52 that moves along the auxiliary transmission shaft 35 to the front gear shaft 34. The rotational power is transmitted to the transmission shaft 35 by meshing with the rear main transmission shaft 45, meshing with the rear gear 53, and meshing with the reduction gear 54 meshing with the gear 53. It has a configuration. A bevel pinion gear 55 is provided at the rear end of the auxiliary transmission shaft 35, and meshes with a bevel ring gear 56 of the differential gear.

In addition, the linkage with the front wheel take-out shaft linked to the front wheels is performed from the gear 57 at the rear end of the auxiliary transmission shaft 35, through the gear 58 at the rear end of the gear shaft 45, and to the front wheel clutch gear 59 on the front wheel take-out shaft 17. The front wheel clutch gear 59 is disengaged from the gear 58 so as to stop driving the front wheels. In the power transmission structure of the tractor configured as described above, in particular, one of the gears of the forward / reverse switching device 16 is constituted by a two-stage gear, and a canter gear that transmits power from the two-stage gear 15 to the back gear 61 is used. Since this is meshed as the power take-off gear 14, the device is simplified and the parts cost is reduced as compared with a configuration in which a reduction gear or a shaft is separately provided for external power take-out and the rotational power is branched. be able to.

[Brief description of the drawings]

FIG. 1 is a side view showing the inside of a transmission case of a tractor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Clutch 2 Clutch housing 3 Input shaft 4 Power take-out interlocking shaft 5 Main transmission 6 Sub-transmission 7 Transmission case 8 Connection housing 9 Front bearing case 10 Travel drive shaft 11 Power take-off drive shaft 15 Two-stage gear 16 Forward / reverse switching device 29 External power take-off shaft

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Matsuhiko Tsunekawa 1 Toyo-cho, Tobe-cho, Iyo-gun, Ehime Pref.

Claims (1)

[Claims] 1. A forward gear 15 that constantly rotates by transmitting the rotational power on a traveling system drive shaft 10 that transmits rotational power of an engine, and a reverse gear that always rotates reversely with respect to the forward gear 15. 61 and the two gears 1
The rotation of one of the two gears 15 and 61 is transmitted by the operation of the clutch 60 provided between the drive shaft 10 and the drive shaft 10.
A forward-reverse switching device 16 that transmits the gears to one another, and one of the gears of the forward-reverse switching device 16 is constituted by a two-stage gear;
A tractor power transmission structure in which a power take-off gear 14 interlocked with an external power take-off shaft 29 is engaged with the gear.