JPS6318258Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a transmission for a tractor, and allows the transmission to be configured to suit the purpose of work while also allowing each case that is the structure of the vehicle body to be used for the same purpose. The purpose is to make it easy.

Tractors are used as power systems for various agricultural operations, and
They are widely used for light civil engineering work, and require a wider variety of gear changes than passenger cars.

Conventionally, transmissions and cases that form the vehicle body structure housing the transmissions have been specialized for each purpose of work and use, but this has caused problems in terms of productivity.

In addition, in order to make most of the vehicle body structure dual-purpose, for example, an intermediate case is interposed between the main transmission case and the auxiliary transmission case, and a transmission mechanism such as a creep mechanism is built into the intermediate case. This makes assembly and disassembly very troublesome, and the exterior structure of the vehicle body is also complicated.

This invention was devised to solve the problems of the conventional technology in view of the actual situation, and is a double clutch mechanism consisting of a traveling clutch and a PTO clutch in a clutch housing fixed to the engine side. The clutch housing has a partition wall that partitions the clutch housing in the front and rear direction. A propulsion shaft case supporting the clutch release mechanism is attached to the front side of the partition wall,
A propulsion shaft for running and a PTO are inserted into the propulsion shaft case by penetrating the partition wall, and transmission cases each having a different type of transmission mechanism are replaceably attached to the rear side of the partition wall, The input side transmission mechanism of the transmission case is provided on the driving propulsion shaft, the output shaft having the output side transmission mechanism is supported in parallel below the propulsion shaft, and the transmission case surrounding the transmission case is a clutch housing. The PTO is removably attached to the PTO and is linked to the PTO transmission mechanism.
The driving propulsion shaft is inserted into the traveling propulsion shaft and protrudes rearward from the propulsion shaft, and connects the input side shaft of the traveling transmission mechanism in the transmission case and the output side shaft of the transmission mechanism in the transmission case. Separable shaft joint and
A shaft joint is provided to connect and separate the PTO propulsion shaft and the PTO transmission shaft, and both shaft joints are located at approximately the same position in the front and back direction. It is characterized by having a bearing that supports each rear end side and a bearing that supports an intermediate portion of the axial length of the output shaft.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a two-axle, four-wheel type tractor 1, where 2 is a pair of left and right front wheels that serve as steering wheels, 3 is a pair of left and right rear wheels that are drive wheels, and 4 is a tower-mounted engine. Covered by bonnet 5.

Various cases and housings are connected to the rear end surface of the engine 4 to form a vehicle body 6, and a transmission shown in FIG. 2 is built into the vehicle body 6. In this embodiment, the pair of left and right front wheels 2 are driven in synchronization with the rear wheels 3 by the propulsion shaft device 7, but the front wheels 2 may be of a non-driven type.

Referring to Figure 2, 8 is the engine output shaft;
A flywheel 9 is fixedly mounted, and a clutch mechanism 10 is attached to the flywheel 9.

In this embodiment, the clutch mechanism 10 is composed of a primary clutch 11 which is a traveling system, and a secondary clutch 12 which is a PTO system.

Reference numeral 13 denotes a flywheel housing, whose front side (the forward direction of the tractor is referred to as the front, and the opposite direction is referred to as the rear) is attached to the rear end surface of the engine with a plurality of bolts (not shown), and encloses the clutch mechanism 10. The rear side has a rectangular opening, and an inspection window 14 is formed in the upper wall, and the window 14 is covered with a removable lid 15.

Reference numeral 16 denotes a clutch housing, the front side of which is open, and the peripheral edge of the opening is removably attached to the rear end surface of the flywheel housing 13 with a plurality of bolts (not shown). In this embodiment, the dividing wall 17 is formed in one piece and encloses the clutch mechanism 10 in cooperation with the flywheel housing.

The upper wall of the clutch housing 16 is inclined backwardly, and the lower wall of the clutch housing 16 is formed with a recessed part 18 that is recessed upward from the lower wall of the flywheel housing. It is located one step lower and divides the vehicle body 6 in the front and rear direction.

Reference numeral 19 denotes a propulsion shaft case, which is fitted with a pilot on the front side of the partition wall 17 and detachably attached with a plurality of bolts, and the case 19 has a cylindrical shape.

Reference numeral 20 denotes a propulsion shaft of the traveling system, which has a cylindrical shaft shape in this example, and has a clutch plate of the primary clutch 11 attached to its front end, is inserted into the propulsion shaft case 19 and penetrates the partition wall 17, In the example, it is rotatably supported by the partition wall 17 via a ball bearing 21 .

Reference numeral 22 denotes a propulsion shaft of the PTO system, the front end of which is rotatably supported by the engine output shaft in this example, inserted into the propulsion shaft 20 of the traveling system, and protruded largely rearward from the shaft 20. A clutch plate of the secondary clutch 12 is attached to the propulsion shaft 22.

Reference numeral 23 denotes a clutch release mechanism, which is supported by the propulsion shaft case 19 and fitted onto the shaft so as to be slidable at least in the axial direction (back and forth direction), and a release fork 24 is engaged with the release mechanism 23. The release fork 24 is supported by the clutch housing via a shaft 25 so as to be able to swing freely in the front and rear directions, and is supported by a clutch pedal (not shown).
The primary clutch and the secondary clutch can be freely engaged and disengaged via a release mechanism using an operating tool such as a clutch operating lever, and the propulsion shafts 20 and 22 can be engaged and engaged here. Usually, the clutch mechanism 10 is a so-called two-stage clutch in which the primary clutch 11 is disengaged first and the secondary clutch 12 is disengaged.

Reference numeral 26 denotes a transmission case, and in the embodiment shown in FIG. 2, it has a transmission mechanism 27 that can be freely switched between forward and reverse directions, and in FIG.
9, and thus a transmission case having different types of transmission mechanisms is attached to the rear side of the partition wall 17 so as to be replaceable.

In the example shown in FIG.
31 is fitted with a spline or the like at an axial interval, and gears 34 and 35 of different diameters rotate at an axial interval on an output shaft 33 which is supported in the transmission case 26 via a bearing 32 with the axial direction being the front-rear direction. The gears 30 and 34 are freely supported and are provided with a shifter that engages and disengages the gears 34 and 35 from the output shaft 33. 35 is in constant occlusion as shown in the figure.

By engaging the gears in this manner, the front end surface of the transmission case 26 shown in FIG. The fitted bearing 36 can be fitted to and removed from the partition wall 17, and when the transmission case 26 is attached, the output shaft 33 projects rearward in parallel with the propulsion shaft 20 and the like.

Furthermore, a bearing 37 that supports the rear end of the propulsion shaft 20 and a bearing 38 that supports the rear end of the propulsion shaft 22 are fitted into the transmission case 26, and the lower wall of the transmission case 26 is open. ing.

The transmission case 28 shown in FIG. 3 has almost the same shape as the transmission case 26 shown in FIG. 2, except that the gears 30 and 34 in FIG. It differs only from the embodiment of FIG. 2, and therefore common parts are designated by common reference numerals. In addition, in the illustrated example, the transmission mechanisms 27 and 29 in the transmission cases 26 and 28 are gear transmissions for forward/reverse switching and high/low switching, but they may also be hydraulic transmissions, and various types of high/low switching are available. It is possible.

Furthermore, in FIG. 2, numeral 39 is a first transmission case, which in this embodiment has a built-in transmission mechanism 40 with four-stage gears of a constant engagement type, and the front end surface of the case 39 is connected to the transmission case 26 or the transmission case 26. 28 and is removably attached to the rear end surface of the partition wall 17 with a plurality of bolts (not shown).

The transmission mechanism 40 has variable diameter transmission gear groups 44 rotatably fitted on a cylindrical transmission shaft 43 supported by bearings 41 and 42 at intervals in the axial direction.
can be freely engaged and disengaged from the speed change shaft 44 by the shifter 45, and the bearings 45, 4 are connected below the speed change shaft 44.
Transmission gear group 4 is mounted on input shaft 47 supported in parallel at 6.
8 is fixedly installed, and the gear group 48 is meshed with the corresponding transmission gear group 44.

Furthermore, the transmission shaft 43 of the transmission mechanism 40 is the propulsion shaft 20.
The input shaft 47 is in the shaft extension position of the transmission mechanism 2.
It is located on the axial extension of the output shaft 33 of No. 7, 29.

The rear end portions of the output shafts 33 of the transmission mechanisms 27 and 29 and the input shaft 47 of the transmission mechanism 40 are connected to a shaft joint 49.
are joined in the axial direction so that they can be freely joined and separated.

50 is the second mission case, height 2
A gear transmission mechanism 51 that can freely change gears is built in, and the transmission mechanism 51 is interlocked with a rear wheel differential mechanism 52. The gear transmission mechanism 51 includes a cylindrical transmission shaft 53 rotatably supported on an axial extension of the propulsion shaft 20.
A gear group 55 is provided in constant engagement with the drive pinion shaft 54, and high and low speeds can be changed by a shifter 56.
It is joined with.

The second transmission mechanism has a built-in transmission mechanism 51 and a differential mechanism 52.
The mission case 50 is detachably attached to the rear end surface of the first mission case 39 with bolts (not shown) or the like.

Also, at the rear end of the second mission case 50,
A PTO transmission mechanism 58 is built-in and is linked to a PTO shaft 59, and its input shaft 60 is connected to the transmission shafts 43 and 5.
3, the front end is joined to the propulsion shaft 22 with a shaft joint 61, and the rear end is joined to a speed change shaft 63 with a shaft joint 62.

Reference numeral 64 denotes a transmission shaft for driving the front wheels, which is interlocked with the drive pinion shaft 54 via a gear 65, etc., and is extended and supported toward the recess 18 of the clutch housing, and the gear interlocking mechanism provided in the recess 18. A case 67 enclosing the interlocking mechanism 66 is removably attached to the lower surface of the recess 18, and 68 is an on/off clutch.

Next, to outline the transmission path of the transmission shown in FIG. 2, the clutch mechanism 10 is engaged and disengaged by sliding the clutch release mechanism 23 in the front and back direction.
The propulsion shaft 20 is interrupted.

In the case of FIG. 2, the propulsion shaft 20 has a transmission case 26 having a transmission mechanism 27 that can freely switch between forward and reverse directions, and is attached to the partition wall 17 of the clutch housing 16. Therefore, when the shifter 36 slides, the output shaft 33 is rotated forward and reverse by receiving engine power.

A transmission mechanism 40 is connected to the output shaft 33 via a shaft joint 49.
An input shaft 47 is connected thereto, and by sliding a shifter 45 of the transmission mechanism 40, the transmission mechanism 40 changes gears in four steps.

Further, a transmission mechanism 51 that can freely change the height in conjunction with the transmission mechanism 40 is built into the second transmission case 50, and a differential mechanism 52 is interlocked via the transmission mechanism 51, so that the rear wheels 3 can be moved to a terminal (not shown). In this example, by bringing the clutch 68 into contact, the front wheels 2 are driven in synchronization with the rear wheels 3 via the propulsion shaft device 7, and the transmission mechanism 40 By providing a so-called shuttle mechanism in front of the transmission which can freely switch between forward and reverse directions, the transmission can be made suitable for, for example, loading work in which forward and reverse operations are frequently repeated.

Next, as shown in FIG. 3, when the transmission case 28 having the transmission mechanism 29 which can be freely switched in height is attached to the partition wall 17, the transmission mechanism 40 is moved by sliding the shifter 36.
The so-called high/low settings are made on the front side of the gearbox, allowing for a richer and finer range of gear changes.

Note that when configured as shown in FIG. 3, the transmission mechanism 4
A back mechanism is provided at either one of 0 or 51 or in the middle thereof.

Therefore, in order to change from the transmission shown in FIG. 2 to the transmission shown in FIG. , Next, the transmission case 2 having the transmission mechanism 29
8 is mounted on the propulsion shaft 20 and the case 28 is attached to the partition wall 17.

Then, the first transmission case 39 having the shaft joints 49 and 61 is pushed forward from the rear, and the shaft joint 49 is connected to the output shaft 33, and the shaft joint 61 is connected to the propulsion shaft 2.
2, and the front end of the transmission case 39 is attached to the partition wall 17 of the clutch housing 16 using bolts not shown in the drawings. The transmission cases 26 and 28 having the mechanisms 27 and 29 can be replaced, and they also serve as constituent members of the vehicle body 6.

Note that in this example, the propulsion shaft 22 can also change the speed of the PTO system via the speed change mechanism 68.

In this invention, a partition wall that partitions the vehicle body in the front and rear direction is formed on the clutch housing that is fixedly installed on the engine side, and a propulsion shaft case that supports the clutch release mechanism is attached to the front side of the partition wall, and the propulsion shaft case is linked to the propulsion shaft. Since the transmission case with the transmission mechanism is attached to the rear side of the partition wall, replacing the transmission mechanism inside the transmission case with a different type requires disassembling the mechanism on the front side of the partition wall, such as the propulsion shaft case. This means that the transmission can be easily modified to suit each application. Therefore, there is no need for specialization as in the past, so productivity can be improved.

In addition, a transmission case with a built-in transmission mechanism can be attached to and removed from the partition wall so as to wrap around the transmission case attached to the partition wall, and the input shaft of the transmission mechanism and the transmission mechanism output shaft of the transmission case can be connected and separated. The provision of a shaft joint makes it extremely easy to assemble different types of transmission cases to the partition wall, and since the transmission case can also be used together with the clutch housing, it is possible to assemble cases even though the transmission mechanisms are of different types. It can be used for both purposes, making it easier to configure the vehicle body.

The propulsion shaft for traveling that penetrates the partition wall is equipped with an input side transmission mechanism, and the output shaft having the output side transmission mechanism is supported below the propulsion shaft, so that the input side transmission mechanism and the output side transmission mechanism are connected. The front and rear lengths can be shorter than those arranged in parallel in the axial direction.

Further, since the transmission case has bearings that support the rear end sides of the travel propulsion shaft and the PTO propulsion shaft and the intermediate portion of the shaft length of the output shaft, each shaft can be reliably supported.

Furthermore, since both the shaft joint on the rear end side of the PTO propulsion shaft and the shaft joint on the output shaft are at approximately the same position in the front-rear direction, when the two shaft joints are used to freely connect and separate, the joint and separation state of the two is mutually different. It is also easy to confirm.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention. Figure 1 is a side view of the external appearance of the tractor, Figure 2 is a side sectional view showing the inside of the transmission mechanism, and Figure 3 is a main part when the transmission mechanism is changed (replaced). FIG. DESCRIPTION OF SYMBOLS 1... Tractor, 4... Engine, 6... Vehicle body, 10... Clutch mechanism, 16... Clutch housing, 17... Partition wall, 19... Propulsion shaft case, 20... Propulsion shaft, 23... Clutch Release mechanism, 26, 28... Transmission case, 27, 29...
...Transmission mechanism, 33...Output shaft, 39...Mission case, 40...Transmission mechanism, 47...Input shaft,
49...Shaft joint.

Claims (1)

[Scope of utility model registration request] A double clutch mechanism 10 consisting of a clutch 11 for traveling and a clutch 12 for PTO is installed in a clutch housing 16 fixedly installed on the side of the engine 4, and the double clutch mechanism 10 is engaged and disengaged for propulsion for traveling and for PTO. The power of the engine 4 is transmitted through the shafts 20 and 22 to the transmission mechanism 40 in the transmission case 39 and the transmission mechanism 5 in the transmission case 50.
8, the clutch housing 16 has a partition wall 17 that partitions it in the front and rear direction, and a propulsion shaft case 19 that supports the clutch release mechanism 23 is attached to the front side of the partition wall 17. Propulsion shaft 20, 2 for traveling and PTO
2 is inserted through the partition wall 17, and
Transmission cases 26 and 28 having different types of transmission mechanisms 27 and 29, respectively, are replaceably attached to the rear side of the partition wall 17, and the input side transmission mechanisms 30 and 31 of the transmission cases 26 and 28 are connected to the driving propulsion shaft 20. An output shaft 33 having transmission mechanisms 34 and 35 on the output side is supported in parallel below the propulsion shaft 20, and a transmission case 39 that encloses the transmission cases 26 and 28 is detachably attached to the clutch housing 16. is attached to the PTO transmission mechanism 58 and is linked to the PTO transmission mechanism 58.
The PTO propulsion shaft 22 is inserted into the traveling propulsion shaft 20 and protrudes rearward from the propulsion shaft 20, and is connected to the input side shaft 47 of the traveling transmission mechanism 40 in the transmission case 39 and the transmission cases 26, 28. Transmission mechanism 2
A shaft joint 49 that connects and separates the shaft 33 on the output side of 7 and 29 and a shaft joint 61 that connects and separates the PTO propulsion shaft 22 and the PTO transmission shaft 60 are provided at approximately the same position in the front and rear direction. Furthermore, the transmission cases 26 and 28 have bearings 37, 32, and 38 that support the respective rear end sides of the traveling propulsion shaft 20 and the PTO propulsion shaft 22 and the intermediate axial length of the output shaft 33. A tractor transmission characterized by: