JPH0656195B2 - Agricultural tractor transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a configuration and an arrangement of a main transmission that shifts forward and backward among transmissions for agricultural tractors.

(B) Conventional Technology In the transmission mechanism, a technology in which a synchromesh transmission is arranged has been conventionally known. For example, Japanese Unexamined Patent Publication No. 49-105065 and Japanese Utility Model Publication No. 57
It is like the technique described in Japanese Patent No. 28923.

(C) Problems to be Solved by the Invention The present invention relates to a gearbox of a synchromesh transmission for reverse gear shifting in a transmission of an agricultural tractor configured by arranging a plurality of synchromesh transmissions as described above. The reverse rotation free-fitting gear to be meshed is shared by the other first synchromesh shaft without separately providing the reverse rotation free-fitting gear shaft, so that the synchromesh is formed by the three shafts arranged at the positions of the apexes of the triangle. This is a compact type transmission mechanism.

(D) Means for Solving the Problems The object of the present invention is as described above, and a configuration for achieving the object will be described below.

The first synchromesh axis 13 and the second synchromesh axis 14 are arranged at the positions of the two base vertices of the triangle whose apex is the counter axis 12, and a plurality of first synchromesh axes 13 and second synchromesh axes 14 are provided. A synchromesh transmission for rearward shifting is arranged on the second synchromesh shaft 14 in a configuration in which a synchromesh transmission is arranged and the rotation after shifting is transmitted to the counter shaft 12 by the plurality of synchromesh transmissions. 34 is arranged, and the reverse rotation loose fitting gear 8 meshing with the gear 7 of the synchromesh transmission 34 is loosely fitted on the first synchromesh shaft 13 to make the reverse rotation loose fitting gear 8 and the counter shaft 12 The gear is meshed with the upper gear 9.

(E) Embodiments and Functions The objects and configurations of the present invention are as described above. Next, detailed configurations of the present invention will be described based on the configurations of the embodiments shown in the accompanying drawings.

FIG. 1 is an overall side sectional view of a transmission of an agricultural tractor according to the present invention, and FIG. 2 is an enlarged sectional view of a synchromesh type main transmission.

The transmission of the agricultural tractor includes a clutch housing C,
Three cases, a transmission case M and a rear axle housing R, are connected and arranged inside thereof.

In the clutch housing C, the PTO main clutch device 2
2 and the traveling main clutch device 23 are configured as a dual clutch device. Therefore, when the clutch pedal is depressed one step, the traveling clutch device is disengaged, and when the clutch pedal is further depressed one step, the PTO clutch device is disengaged.

The rotation of the PTO clutch device after connection and disconnection is transmitted to the inside of the mission case M via the PTO main clutch shaft 2.
The rear end of the PTO main clutch shaft 2 is transmitted to the shaft 15 via the coupling, and is loosely fitted on the hydraulic clutch shaft 18 from the gear 30 on the shaft 15 via the gear 31 loosely fitted on the counter shaft 12. It is transmitted to the gear 32.

The hydraulic clutch device 33 is a PTO clutch device
It is used when the rotation of the TO shaft 21 is frequently connected and disconnected. The rotation of the hydraulic clutch device 8 is transmitted to the gear 37, the gear 39, the gear 41, and the gear 43. Gear 37
The gear 39, the gear 41, and the gear 43 are constantly meshed with the gear 38, the gear 40, the gear 42, and the gear 44 on the shaft 19, respectively, and the left and right movements of the shift shifters 70 and 71 cause the PT to move.
O shift is performed in four steps. The rotation after the PTO gear shift is transmitted from the shaft 19 to the PTO shaft 21 via the coupling.

The above is a description of the configuration of the PTO transmission.
Next, the main transmission device for traveling speed change will be described.

The rotation after being engaged and disengaged by the traveling main clutch device 23,
It is transmitted to the fixed gear 3 via the main traveling clutch shaft 1.
The fixed gear 3 is a loose fitting gear 4 loosely fitted on the counter shaft 12.
Power is transmitted to the loose fitting gear 4 having a wide width,
The fixed gear 5 on the synchromesh shaft 13 and the fixed gear 6 on the second synchromesh shaft 14 are simultaneously meshed.

The first synchromesh shaft 13 and the second synchromesh shaft 14 are arranged at the apexes of the base of the substantially isosceles triangle whose apex is the counter shaft 12.

On the first synchromesh shaft 13, a gear 26
The gear 29 is fixed, and the gear 26 and the gear 29 mesh with the fixed gears 27 and 28 on the upper counter shaft 12. One of these two sets of gear trains is selected by the synchromesh transmission 35. As a result, the first forward speed and the third forward speed can be obtained.

Further, the second synchromesh shaft 14 is driven by the fixed gear 6, and the fixed gear 7, on the second synchromesh shaft 14,
10 is rotated. The gear 7 is a first synchromesh shaft 1 which is a shaft on which another synchromesh device is installed.
3 is meshed with the fixed gear 9 on the counter shaft 12 through the reverse rotation loosely fitted gear 8 which is loosely fitted on the counter shaft 12. The gear 10 is directly meshed with the fixed gear 11 on the counter shaft 12. . By selectively connecting one of the two gear trains by the synchromesh transmission 34, the second forward speed and the reverse speed can be obtained.

The above is the synchromesh type main transmission, and the rotation after shifting in the main transmission is transmitted from the counter shaft 12 to the creep transmission.

That is, the gear 47 at the rear end of the counter shaft 12 meshes with the fixed gear 46 of the creep counter shaft 16, and further passes through the creep counter shaft 16 and bypasses the gear 45 to the gear 49 on the shaft 17 to transmit power. Is configured to be possible. The shift shifter 48 selects either this detour gear train or the direct connection between the counter shaft 12 and the shaft 17. As a result, creep speed change is performed. Further, a gear-sliding auxiliary shift is performed between the shaft 17 and the pinion shaft 20.

That is, the fixed gears 51, 52, 53 on the shaft 17 and the gears 54, 55, 57 on the pinion shaft 20 mesh with each other, and one of the three gear trains is moved forward and backward by the shift shifter 56. Select with and shift to 3 speeds.

Further, the power for driving the front wheels is taken out from the gear 61 at the front end of the pinion shaft 20.

That is, through the loose fitting gears 62 and 63 on the PTO shaft 21,
The power is transmitted to the gear 64 on the shaft 25, and the clutch shifter 65 slides to connect and disconnect the front wheel driving force. From the pinion 58 of the pinion shaft 20, the differential ring gear 59
Transmission power is transmitted.

Reference numeral 60 is a drum for a parking brake, 50 is a traveling inertia slip prevention brake device, and 36 is a drum of a PTO inertia slip prevention brake device.

The configuration of the present invention is as described above, and the traveling main clutch shaft 1
The main feature is that the position of the upper fixed gear 3 and the synchromesh transmissions 34 and 35 are juxtaposed on the different first synchromesh shaft 13 and second synchromesh shaft 14 of the main transmission unit. Further, it is characterized in that the reverse rotation loose fitting gear 8 of the reverse gear train is loosely fitted on the first synchromesh shaft 13 on which the other synchromesh device is installed.

In addition, after the main transmission clutch shaft 1 once transmitted to the intermediate position of the transmission case M, the gear train and the synchromesh type transmission again transmit power to the front like turning up and then power to the rear again. "Of" to convey
The point is that the power is transmitted by drawing the letters.

(F) Effects of the Invention Since the present invention is configured as described above, it has the following effects.

Firstly, the transmission of the agricultural tractor in which a plurality of sets of synchromesh transmissions are arranged is large in size, and therefore, if a shaft for the reverse rotation loosely fitted gear is further provided, the transmission case becomes larger. However, according to the present invention, the counter shaft 12 and the first synchromesh shaft 13 are
And the second synchromesh shaft 14 are arranged at the positions of the vertices of the triangle, and the reverse fitting free-fitting gear 8 of the reverse synchromesh transmission 34 arranged on the second synchromesh shaft 14 is By loosely fitting on the 1-synchromesh shaft 13, the reverse rotation loose fitting gear shaft can be eliminated,
A plurality of synchromesh transmissions can be compactly arranged on the three shafts.

As a result, the transmission of the agricultural tractor equipped with the synchromesh transmission can be made compact.

[Brief description of drawings]

FIG. 1 is an overall side sectional view of a transmission of an agricultural tractor according to the present invention, and FIG. 2 is an enlarged sectional view of a synchromesh type main transmission. 1 ... Running main clutch shaft 2 ... PTO main clutch shaft 4 ... Free-fitting gear 8 ... Reverse rotation free-fitting gear 12 ... Counter shaft 13 ... First synchromesh shaft 14 ... Second synchromesh shaft 34 , 35 …… Synchromesh transmission

Claims (1)

[Claims] 1. A triangle 2 having a counter axis 12 as an apex.
The first synchromesh shaft 13 and the second synchromesh shaft
The synchromesh shaft 14 is arranged, and a plurality of synchromesh transmissions are arranged on the first synchromesh shaft 13 and the second synchromesh shaft 14, and the rotation after shifting is countered by the plurality of synchromesh transmissions. In the structure for transmitting to the shaft 12, the synchromesh transmission 34 for reverse gear shifting is mounted on the second synchromesh shaft 14.
The gear 7 of the synchromesh transmission 34.
A reverse rotation free-fitting gear 8 meshing with the first reverse rotation loose-fitting gear 8 is loosely fitted on the first synchromesh shaft 13, and the reverse rotation free-fitting gear 8 and the gear 9 on the counter shaft 12 are meshed with each other. Transmission of tractor.