JPS6218369B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission for a vehicle,
The purpose is to increase the number of gears when going in reverse.

In a transmission in a vehicle such as an agricultural tractor, when multi-speed shifting is required, first and second transmission devices are provided, and the transmission can be changed by the number of gears multiplied by the number of gears of each gear. With multiple transmissions like this, the transmission with a small number of gears performs rough shifts between high and low speeds, and the transmission with many gears performs fine shifts within those high and low speeds. Conventionally, the reverse drive system has been incorporated in the transmission device with the largest number of gears because the shift operation is carried out more frequently on the side of the transmission with the larger number of gears. For this reason, multi-speed gear shifting is possible for forward movement, but for reverse movement, the number of gear stages is extremely small, and since it matches the number of gear stages with fewer gear stages, the speeds are extremely different. When carrying out loading work while repeatedly moving forward and backward while wearing a
The drawbacks were that work efficiency was poor and it was difficult to grasp the driving sensation when moving forward or backward.

The present invention solves these conventional problems, and is characterized in that a traveling main shaft 20 is rotatably fitted onto a PTO main shaft 12 that is linked to an engine 9, and that the traveling main shaft 20 is A first speed change shaft 34 is disposed below 20, a first speed change device 46 is provided between the traveling main shaft 20 and the first speed change shaft 34, and a first speed change device 46 is provided on the rear side of the first speed change device 46. A second transmission device 6 having fewer gear stages than the device 46
9, the second transmission 69 is
A second speed change shaft 51 that is mounted on the same axis as the first speed change shaft 34 and facing the first speed change shaft 34; The second deceleration shaft 57, the first speed change shaft 34, and the first
A first reduction gear system 65 interlockingly connects with the reduction shaft 47
and the second speed change shaft 51 which is interlocked with the first speed reduction shaft 47 and
A second reduction gear system 66 loosely fitted into the first reduction shaft 4
7 and is loosely fitted to the second speed change shaft 51; and a third reduction gear system 67 that interlocks and connects the first reduction shaft 47 and the second reduction shaft 57 via a second reduction gear system 66. and a fourth reduction gear system 68 that interlocks with the second reduction shaft 57 and loosely fits into the second speed change shaft 51;
A first clutch 63 for selectively connecting the first speed change shaft 34 and the fourth reduction gear system 68 to the second speed change shaft 51; and a first clutch 63 for selectively connecting the first speed change shaft 34 and the fourth reduction gear system 68 to the second speed change shaft 51; The second gear for connecting to the second gear shift shaft 51
Clutch 64.

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. Transmission 1 is installed in series.

The transmission 1 is covered with a clutch housing 2 and a transmission case 3 connected to the rear of the clutch housing 2. The transmission case 3 has a front part, a middle part, and a transmission case 3.
It is detachably divided into rear cases 4, 5, and 6. A differential device 7 is included in the rear case 6 and connected to the rear wheels 8, and a PTO transmission device is included behind the differential device 7, and this device is protruded from the rear surface of the rear case 6. It is connected to the PTO shaft. These rear wheels and the PTO shaft are driven by an engine 9 via the transmission 1.

A flywheel 11 is attached to the rear end of the crankshaft 10 supported by a bearing in the crankcase, and the front end of the PTO main shaft 12 in the longitudinal direction of the shaft center is spline-fitted to the center of the wheel 11, and the rear end of the PTO main shaft 12 is supported by a PTO main shaft rear bearing 13, which is held by a PTO main shaft support 14 that is detachably attached to the rear surface of the intermediate case rear wall 5. In addition, there is a PTO at the rear of the PTO main shaft 12.
The intermediate shaft 15 and the PTO rear shaft 16 are sequentially mounted on the same axis, and the PTO main shaft 12 and the PTO intermediate shaft 15
Between is a hydraulically operated wet disc clutch.
It is said that it can be freely connected and disconnected using PTO clutch 17.
The front end of the PTO rear shaft 16 has a PTO that can slide freely in the axial direction.
A shift gear 18 is provided, and the gear 18 is
The PTO rear shaft 16 and the PTO intermediate shaft 15 are detachably connected. In the above case, the PTO main shaft 12 is the drive shaft, the PTO intermediate shaft 15 is the driven shaft, and the PTO clutch 17 is located near the divided end of the front end of the rear case 6.

Front and rear main shafts 19 and 20 each having a cylindrical cross section are fitted in the middle of the PTO main shaft 12 so as to be freely rotatable, and between the front end of the front main shaft 19 and the flywheel 11, A disk-shaped main clutch 21 is attached, and the main clutch 21 can be freely engaged and disengaged by pressing a clutch pedal (not shown). Further, a main shaft clutch 22 is provided between the front and rear main shafts 19 and 20, which is a hydraulically operated wet disc clutch that can freely connect and disconnect these two shafts 19 and 20. Main shaft one-way clutch 2 that transmits power only to
3 is provided. Further, a front main shaft gear 24 is fixed to the front main shaft 19, and a rear main shaft gear 25 is fitted onto the front of the rear main shaft 20 so as to freely rotate. A one-way clutch 26 is provided for transmitting power only to the second main shaft.

An intermediate shaft 27 parallel to these shafts 19 and 20 is mounted below the front and rear main shafts 19 and 20, and the first and second intermediate gears 2 are mounted on the intermediate shaft 27.
8 and 29 are fixed to the front and rear main shaft gears 2, respectively.
4 and 25 are always engaged.

In the rear part of the front case 4, first, second, third, and fourth drive gears 30, 3 whose diameters gradually decrease from the front to the rear are arranged on the rear main shaft 20 at predetermined intervals in the axial direction.
1, 32, and 33 are spline-fitted.Meanwhile, below the rear main shaft 20, a first transmission shaft 34 parallel to the axis is mounted. second, third and fourth transmission gears 35;
36, 37, and 38 can rotate freely, and the transmission gear 3
7 is fitted externally with a spline. These first ~
The four speed change gears are always meshed with the corresponding drive gears. Moreover, the first and second transmission gears 3
Connecting bodies 39 and 40 are spline-fitted to the first speed change shaft 34 between the gears 5 and 36 and between the third and fourth speed change gears 37 and 38, respectively. Shifter 41 fitted with splines,
42 can freely engage and disengage the coupling bodies 39, 40 and each transmission gear, and a four-stage transmission can be selected from the rear main shaft 20 to the first transmission shaft 34. The shifters 41 and 42 are made selectively movable in the axial direction by operating shift forks 44 and 45 in conjunction with manual operation of the first speed change lever 43. The rear main shaft 20, the first transmission shaft 34, and a group of gears on these shafts constitute a first transmission 46 capable of shifting in four stages.

Inside the substantially intermediate case 5, a first reduction shaft 47 having a cylindrical cross section is mounted so as to fit around the PTO main shaft 12, and a passive gear 48 and a reverse drive are sequentially connected to the first reduction shaft 47 from the front to the rear. The gear 49 and the fifth drive gear 50 are integrally molded or spline-fitted, and a second speed change shaft 51 is coaxially coaxial with the first speed change shaft 34 below the first speed reduction shaft 47. The second speed change shaft 51 is connected to the sixth speed change gear 52, the reverse gear 54 which is always meshed with the reverse drive gear 49 via the idle gear 53, and the fifth drive gear 50 from the front to the rear. A fifth speed change gear 55, which is always engaged, is freely rotatable.
The idle gear 53 is loosely fitted to the reverse shaft 56.
A second speed reduction shaft 57 having a cylindrical cross section is mounted below the second speed change shaft 51, and a seventh speed change gear 5, which is constantly meshed with the sixth speed change gear 52, is mounted on the second speed reduction shaft 57.
8 and a ninth speed change gear 60, which is always meshed with the eighth speed change gear 59 integrally molded with the fifth speed change gear 55, are integrally molded or spline-fitted.
Connection bodies 61 and 62 are spline-fitted onto the second transmission shaft 51 between the transmission gear 39 and the sixth transmission gear 52 and between the reverse gear 54 and the fifth transmission gear 55, respectively. are provided with shifters 63 and 64 that are externally fitted with splines so as to be slidable in the axial direction, and these shifters 63 and 64 can freely engage and disengage the coupling bodies 61 and 62, respectively, and the gears on the second speed change shaft 51. It makes up the clutch. In addition,
The transmission gear 39 and the rear gear 48 provide a first reduction gear system 65, a fifth drive gear 50, and a fifth transmission gear 55.
The second reduction gear system 66 and the eighth transmission gear 59
and the ninth speed change gear 60, the third reduction gear system 6
7. The seventh speed change gear 58 and the sixth speed change gear 52 constitute a fourth reduction gear system 68, and these reduction gear systems 65, 66, 67, 68, the second speed change shaft 51, and the first and second 3 due to the reduction shafts 47 and 57.
A second transmission device 69 capable of speed change is configured. This second transmission 69 includes a reverse drive gear 4.
A reverse gear system 70 consisting of 9, an idle gear 53, and a reverse gear 54 is incorporated, so that when traveling in reverse, the vehicle can shift up to the number of gears of the first transmission 46, that is, up to 4 gears. The shifters 63 and 64 constitute a connecting means, and can be selectively operated by a second shift lever (not shown), and by this selection operation, the second shift shaft 5
1 to high, medium, very low speed and reverse rotation.

Thus, when the first shifter 63 is engaged with the transmission gear 39, the second shift shaft 61 is connected to the first shift shaft 34.
It is directly connected to provide high speed rotation. Moreover, if the second shifter 64 is engaged with the fifth speed change gear 55, the first speed change shaft 34→transmission gear 39→passive gear 4
8 → first reduction shaft 47 → fifth drive gear 50 → fifth transmission gear 55 → second shifter 64 → second transmission shaft 51
The power is sequentially transmitted, and the second speed change shaft 51 is given medium speed rotation. Furthermore, when the first shifter 63 is engaged with the sixth speed change gear 52, the first speed change shaft 34→transmission gear 39→passive gear 48→first reduction shaft 47→fifth drive gear 50→fifth speed change gear 55 → 8th speed change gear 59 → 9th speed change gear 60 → 2nd speed change gear 57 → 7th speed change gear 58 → 6th rotating gear 52 → 1st shifter 63 → 2nd speed change shaft 51. Power is transmitted in this order, and the power is transmitted to the second speed change gear. The shaft 51 is given very low speed rotation. Furthermore, when the second shifter 64 is engaged with the reverse gear 54, the first shift shaft 34→transmission gear 39→passive gear 4
8 → first reduction shaft 47 → reverse drive gear 49 → idle gear 53 → reverse gear 54 → second shifter 64
→Power is sequentially transmitted 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 second shifter 64 back and forth, and therefore, it is possible to switch between forward and backward by simply operating the second shift lever, for example, in the front and rear directions.
When carrying out loading work with a front loader installed, shifting operations are 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 behind the second speed change shaft 51 on the same axis as the shaft 51, and is interlocked with a large differential gear 73 of the differential device 7 via a differential pinion 72. The differential pinion shaft 71 has a
A tenth speed change gear 74 is spline-fitted, and the tenth speed change gear 74 and the PTO shift gear 18 can be freely engaged and disengaged by sliding the shift gear 18 in the axial direction. Further, a propulsion shaft 75 is inserted through the second deceleration shaft 57 and is coaxial with the shaft 57.
and a third speed change shaft 76 which are coaxially centered behind the propulsion shaft 75, respectively, and an eleventh speed change gear 77 spline-fitted to the third speed change shaft 76 and the tenth speed change gear 77 are spline-fitted to the third speed change shaft 76.
The transmission gear 74 is always meshed with the transmission gear 74.
Further, the propulsion shaft 75 and the third transmission shaft 76 can be connected and connected by a propulsion clutch 78 which is a hydraulically operated wet disc clutch. Note that the propulsion shaft 75 is for front wheel drive.

It goes without saying that each shift lever is operated along an H-shaped shift guide groove.

In the present invention, since the reverse gear system 70 is provided on the side of the second transmission 69 which has a smaller number of gears than the first transmission 46, it is possible to shift gears by the number of gears of the transmission which has a larger number of gears when traveling backwards. Therefore, for vehicles that frequently need to repeatedly go forward and backward, you can select any speed as needed when reversing, making it possible to work more efficiently and at the same time making it easier to understand the driving sensation and adjusting the speed to suit the conditions. I can drive well. The first speed change shaft 34 and the second speed change shaft 51 are mounted facing each other on the same axis, and the first speed change shaft 47 and the second speed change shaft 5 are mounted above and below the second speed change shaft 51.
7 and these axes 34, 47, 51, 57
The first to fourth reduction gear systems 65, 66, 6 are connected between each other.
7 and 68, and first and second clutches 63 and 64, three-stage speed change of high, medium and low speeds is possible by operating these clutches 63 and 64.
Furthermore, at low speeds, the first to fourth reduction gear systems 65, 6
6, 67, and 68 are connected in series, an extremely low speed can be obtained, and even though the speed is extremely low, the entire second transmission 69 cannot be constructed compactly, which is advantageous. Further, a reverse gear system 70 is provided between the first speed reduction shaft 47 and the second speed change shaft 51, and the reverse speed gear system 70 and the second speed reduction gear system 66 are selectively connected to the second speed change shaft 51 by a second clutch 64. Therefore, by operating the second clutch 64, it is possible to select between medium speed and reverse. Therefore, when this selection is made, the first reduction gear system 65 is commonly connected to the front stage, and the high speed Compared to those that select side and reverse,
The speed does not change drastically when moving forward and backward, and when work is performed by frequently repeating forward and backward movement, the work can be done efficiently while moving forward and backward at relatively similar speeds.

[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, 70...Reverse gear system .

Claims (1)

[Claims] 1. 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 is disposed below the traveling main shaft 20, and the first transmission shaft 34 is disposed between the traveling main shaft 20 and the first transmission shaft 34. A first transmission 46 is provided at the rear of the first transmission 46, and a second transmission 69 having a smaller number of gears than the first transmission 46 is provided. A second speed change shaft 51 that is mounted on the same axis as the first speed change shaft 34 and facing the first speed change shaft 34; The second speed reduction shaft 57 and the first speed change shaft 3
4 and the first reduction shaft 47, a second reduction gear system 66 which interlocks with the first reduction shaft 47 and loosely fits into the second speed change shaft 51,
a reverse gear system 70 that interlocks with the reduction shaft 47 and loosely fits into the second transmission shaft 51; and a third reduction gear that interlocks and connects the first reduction shaft 47 and the second reduction shaft 57 via a second reduction gear system 66. system 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 selectively shifts the first speed change shaft 34 and the fourth reduction gear system 68 to the second speed change. the first for connecting to the shaft 51;
A vehicular transmission comprising a clutch 63 and a second clutch 64 for selectively connecting a second reduction gear system 66 and a reverse gear system 70 to a second transmission shaft 51.