JPS6125933B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission for a vehicle.

Vehicles such as agricultural tractors require extremely low speeds due to their work, but conventionally, for example,
As shown in Publication No. 112369, an ultra-low-speed transmission is equipped separately from the normal transmission, which increases the size of the transmission as a whole and provides a large number of independent transmission control systems. Both the structure and the handling were extremely complicated.

The present invention aims to solve these conventional problems, and its features include rotatably fitting the traveling main shaft to the PTO main shaft that is linked to the engine, and A first transmission shaft and another transmission shaft are disposed sequentially below the main travel shaft, a first transmission is provided between the main travel shaft and the first transmission shaft, and a first transmission is provided on the rear side of the first transmission. In a device provided with a second transmission, the second transmission is
A second speed change shaft is mounted so as to face the first speed change shaft on the same axis, a first speed reduction shaft and a second speed reduction shaft are loosely fitted to the PTO main shaft and the transmission shaft, and a first reduction gear system that interlocks and connects the reduction shafts;
a second reduction gear system that interlocks with the reduction shaft and loosely fits into the second transmission shaft; a third reduction gear system that interlocks and connects the first reduction shaft and the second reduction shaft via the second reduction gear system; a fourth reduction gear system interlocking with the second speed reduction shaft and loosely fitted to the second speed change shaft; and a first clutch for selectively connecting the first speed change shaft and the fourth speed reduction gear system to the second speed change shaft. , and a second clutch for connecting the second reduction gear system to the second transmission shaft.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The figure shows a transmission 1 of an agricultural tractor vehicle, and the transmission 1 is covered with a clutch housing 2 and a transmission case 3 connected to the rear thereof. Mission case 3
is detachably divided into front, middle, and rear cases 4, 5, and 6. The rear case 6 includes a differential device 7 that interlocks with the left and right rear wheels 8, and the differential device 7 includes a PTO transmission, which protrudes from the rear surface of the rear case 6. It is connected to the PTO shaft that is installed. These rear wheels 8 and PTO shaft are driven by an engine 9 at the front end via the transmission 1.

A flywheel 11 is attached to the rear end of the crankshaft 10 of the engine 9.
The front end of the PTO main shaft 12 is spline-fitted to the
Further, the rear end of the PTO main shaft 12 is held via a rear bearing 13 by a support 14 that is detachably attached to the rear surface of the intermediate case rear wall 5. PTO spindle 1
At the rear of 2 are the PTO intermediate shaft 15 and the PTO rear shaft 16.
are mounted sequentially on the same axis, and the PTO main shaft 12 and
The PTO intermediate shaft 15 can be freely connected and disconnected by a hydraulically operated wet disk clutch type PTO clutch 17. A PTO shift gear 18 that is slidable in the axial direction is provided at the front end of the PTO rear shaft 16, and the gear 18 releasably connects the PTO rear shaft 16 and the PTO intermediate shaft 15.

Cylindrical front and rear main shafts 19 and 20 for running are fitted in the middle of the PTO main shaft 12 so as to freely rotate, and a disc-shaped main clutch 21 is disposed between the front end of the front main shaft 19 and the flywheel 11. is attached. Further, a hydraulically operated wet disc clutch type main shaft clutch 22 is provided between the front and rear main shafts 19 and 20 to freely connect and disconnect these two shafts 19 and 20, and a main shaft clutch 22 is provided between the front main shaft 20 and the front main shaft 19. The first one-way clutch 23 transmits power only to
is provided. Further, a gear 24 is fixed to the front part of the front main shaft 19, and a gear 25 is rotatably fitted to the front part of the rear main shaft 20, and power is transmitted only in the direction of the rear main shaft 20 from this gear 25. A second one-way clutch 26 is provided.

An intermediate shaft 27 parallel to these shafts 19, 20 is mounted below the front and rear main shafts 19, 20, and gears 28, 29 that are constantly engaged with gears 24, 25 are mounted on the intermediate shaft 27. It is fixed. Four gears 30, 31, 32, and 33 are spline-fitted onto the rear main shaft 20, and are arranged at predetermined intervals in the axial direction and whose diameters gradually decrease from the front to the rear. On the other hand, below the rear main shaft 20, a first speed change shaft 34 is mounted in parallel, and on the speed change shaft 34, gears 35, 36, 37, 38 that are always in mesh with the gears 30, 31, 32, 33 are mounted. It is fitted on the mantle so that it can freely rotate, and a gear 39 is fitted on the outside with a spline. Gears 35, 36, 3 of the first transmission shaft 34
Connecting bodies 39 and 40 are provided between the connecting bodies 7 and 38, and clutches 41 and 42 are fitted onto the connecting bodies 39 and 40 so as to be slidable in the axial direction and can be freely engaged and disengaged from each gear. . Clutches 41 and 42 are selectively movable in the axial direction by shift forks 44 and 45 that are interlocked with shift lever 43. These rear main shaft 20 and first gear shift shaft 3
4 and the gears on these shafts constitute a first transmission 46 capable of shifting in four stages.

Inside the intermediate case 5, a cylindrical first reduction shaft 47
is mounted on the PTO main shaft 12 so as to fit externally, and gears 4 are sequentially mounted on this first reduction shaft 47 from the front to the rear.
8, 49, and 50 are integrally molded or spline-fitted. On the other hand, a second speed change shaft 51 is located below the first speed reduction shaft 47 on the same axis as the first speed change shaft 34.
is mounted on a shaft, and on the second transmission shaft 51, sequentially from the front to the rear, a gear 52, a gear 54 constantly meshed with the gear 49 via an idle gear 53,
A gear 55, which is always engaged with the gear 50, is freely rotatable. The idle gear 53 is loosely fitted to the reverse shaft 56. A cylindrical second reduction shaft 57 is mounted below the second speed change shaft 51, and the second reduction shaft 57 has a gear 5 which is constantly meshed with the gear 52.
8 and a gear 60 that is always meshed with a gear 59 that is integrated with the gear 55 are integrally molded or spline-fitted. Connecting bodies 61 and 62 are spline-fitted onto the second transmission shaft 51 between the gear 39 and the gear 52 and between the gear 54 and the gear 55, respectively. First and second shifter clutches 63 and 64 are provided which are freely spline-fitted, and these clutches 63 and 64 are connected to the coupling bodies 61 and 62 and the gear 3, respectively.
9, 52, 54, and 55 can be freely disconnected from each other. The gears 39 and 48 constitute a first reduction gear system 65, the gears 50 and 55 constitute a second reduction gear system 66, the gears 59 and 60 constitute a third reduction gear system 67, and the gears 58 and 52 constitute a fourth reduction gear system 68, respectively. The reduction gear systems 65, 66, 67, and 68, the second transmission shaft 51, and the first and second reduction shafts 47 and 57 constitute a second transmission 69 capable of three-stage transmission. A reverse gear system 70 consisting of a reverse drive gear 49, an idle gear 53, and a gear 54 is incorporated in the second transmission 69. Therefore, when traveling backward,
The first transmission 46 can shift up to four gears. The clutches 63, 64 can be selectively operated by a second shift lever (not shown), and this selective operation causes the second shift shaft 51 to rotate at high, medium, very low speeds, and backward.

When the clutch 63 is engaged with the gear 39, the second speed change shaft 61 is directly connected to the first speed change shaft 34 and is given high speed rotation. Also, when the clutch 64 is engaged with the gear 55, the first speed change shaft 34 → gear 39 → gear 8 → first reduction shaft 47 → gear 50
Power is sequentially transmitted to the gear 55, the clutch 64, and the second transmission shaft 51, and the second transmission shaft 51 is given medium speed rotation. Also, when the clutch 63 is engaged with the gear 52, the first speed change shaft 34 → gear 39 → gear 48 → first reduction shaft 47 → gear 51 → gear 5
5→Gear 59→Gear 60→Second reduction shaft 57→
Power is sequentially transmitted through the gear 58 → gear 52 → clutch 63 → second shift shaft 51, and the second shift shaft 51 is given an extremely low speed rotation. Also, if the clutch 64 is engaged with the reverse gear 54, the first gear shift shaft 3
4 → Gear 39 → Gear 48 → First reduction shaft 47 →
Gear 49 → Idle gear 53 → Gear 54 →
Power is sequentially transmitted from the clutch 64 to the second speed change shaft 51, and the second speed change shaft 51 is driven backward. At this time, reverse and medium speeds can be changed by simply sliding the clutch 64 back and forth, and therefore, switching between forward and backward is possible by simply operating the second gear shift lever, for example, in the front and rear directions. When carrying out loading work, the gear shifting operation is easy. In addition, since the reverse movement in this case is the same as the medium speed, forward and backward movement can be performed quickly, and work efficiency is significantly improved.

A differential pinion shaft 71 is mounted on the same axis behind the second speed change shaft 51 and is interlocked with a large differential gear 73 of the differential device 7 via a differential pinion 72 . A gear 74 is spline fitted to the differential pinion shaft 71, and the gear 74 and the PTO
The shift gear 18 can be disconnected from the shift gear 18 by sliding the shift gear 18 in the axial direction.
Further, a propulsion shaft 75 concentrically inserted through the second reduction shaft 57 and a third speed change shaft 76 coaxially located behind the propulsion shaft 75 are respectively mounted, and the third speed change shaft 76
Gear 77 and gear 74 spline-fitted to
are always engaged. Also, the propulsion shaft 75
The third speed change shaft 76 and the third speed change shaft 76 can be connected and connected by a hydraulically operated wet disk clutch type propulsion clutch 78. Note that the propulsion shaft 75 is for front wheel drive.

In the present invention, the first speed change shaft 34 and the second speed change shaft 51
are mounted on opposite axes on the same axis, and the first and second reduction shafts 47, 57 are mounted in parallel, and the first to fourth reduction gear systems 65, 66, 6 are mounted between these shafts.
7, 68, and first and second clutches 63, 64, these clutches 63, 68
By operating 64, it is possible to shift up to three gears.
Also, at low speeds, the first to fourth reduction gear systems 65,
Since 66, 67, and 68 are connected in series, the speed is extremely low.In other words, the extremely low speed system is incorporated into the other two-speed transmission system, so the entire transmission can be made compact, and the operation system can be made compact. Both the structure and handling become easier. Furthermore, in the present invention, the traveling main shaft 20 is rotatably fitted onto the PTO main shaft 12 that is linked to the engine 9, and the first transmission shaft 34 and another transmission shaft 75 are sequentially connected below the traveling main shaft 20. The basic configuration of a device in which a first transmission 46 is provided between the traveling main shaft 20 and the first transmission shaft 34, and a second transmission 69 is provided on the rear side of the first transmission 46 Using as is, the first
A second speed change shaft 5 is located opposite to the speed change shaft 34 on the same axis.
1 is mounted on a shaft, and the first reduction shaft 47 and second reduction shaft 57 are loosely fitted to the PTO main shaft 12 and transmission shaft 75, making it easy to change the design from the conventional transmission. Can be implemented.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the present invention, in which FIG. 1 is a schematic diagram of the entire structure, FIG. 2 is a sectional view of a main part, and FIG. 3 is a sectional view of a reverse drive system. DESCRIPTION OF SYMBOLS 1...Transmission, 46...1st transmission, 34...1st speed change shaft, 47...1st speed reduction shaft, 51...2nd speed change shaft, 57...2nd speed change shaft,
65...First reduction gear system, 66...Second reduction gear system, 67...Third reduction gear system, 68...Fourth reduction gear system, 69...Second transmission.

Claims (1)

[Claims] 1. A traveling main shaft 20 is rotatably fitted onto the PTO main shaft 12 that is linked to the engine 9, and a first transmission shaft 34 and another power transmission shaft 75 are sequentially disposed below this traveling main shaft 20. Main shaft 20 and the first
In a device in which a first transmission 46 is provided between the transmission shaft 34 and a second transmission 69 is provided behind the first transmission 46, the second transmission 69
A second speed change shaft 51 that is mounted on the same axis as the speed change shaft 34 and opposite to the speed change shaft 34, a PTO main shaft 12, and a transmission shaft 75.
The first reduction shaft 47 and the second reduction shaft 57 are loosely fitted into the
, a first reduction gear system 65 that interlocks and connects the first speed change shaft 34 and the first reduction shaft 47, and the first reduction shaft 47.
a second reduction gear system 66 that is interlocked with and loosely fitted to the second speed change shaft 51; and a third reduction gear system that interlocks and connects the first reduction shaft 47 and the second reduction shaft 57 via the second reduction gear system 66. 67, a fourth reduction gear system 68 that interlocks with the second reduction shaft 57 and loosely fits into the second speed change shaft 51, and a first speed change shaft 34 and a fourth reduction gear system 6.
8 to the second speed change shaft 51; and a second clutch 64 for connecting the second reduction gear system 66 to the second speed change shaft 51.
A vehicle transmission characterized by comprising: