KR910005656B1 - Propelling transmission system of tractor - Google Patents

Abstract

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Description

Tractor driving mechanism

The figure shows an embodiment of a traveling transmission mechanism of a tractor according to the present invention.

1 is a side view of an agricultural tractor.

2 is a side view showing the arrangement of the main clutch case, the engine, and the front wheel transmission case.

3 is a longitudinal side view showing the main transmission mechanism and the front wheel transmission.

4 is a cross-sectional plan view of the front wheel shift control mechanism.

5 is a longitudinal rear view of the front wheel shift control mechanism.

6 is a longitudinal side view of the front wheel shift control mechanism.

* Explanation of symbols for main parts of the drawings

1: engine 5: rear derailleur

7: front wheel 8: rear wheel

9: front wheel transmission 10: main clutch case

11: front wheel transmission case 14: main clutch mechanism

15: input shaft 17: first transmission shaft

18: second transmission shaft 50: clutch sleeve

The present invention installs the engine and the main clutch case connected to the rear of the engine on the entire body, and installs a rear transmission at the rear of the body that receives the output from the main clutch mechanism and transmits it to the rear and front wheels, and drives the front wheels at substantially constant speed with the rear wheels. It relates to a drive transmission mechanism of a tractor equipped with a front drive transmission that can be switched to a high speed drive state to drive at a higher speed than the rear wheel and the standard drive state to be mounted in the electric system between the rear derailleur and the front wheel.

In the traveling transmission mechanism of this type of tractor, the front wheel transmission is conventionally installed in the lower part of the front end of the rear transmission provided at the rear of the vehicle body (US Pat. No. 4,457,510).

Therefore, the front wheel shifting device is located at the rear of the vehicle body, so the center of gravity of the traveling body is convenient to the rear side, and work devices such as tillage devices are connected to the rear of the vehicle body, which promotes a tendency to already be in the rear center state, which is very heavy at the front of the vehicle body. Needs a balance pivot.

It is an object of the present invention to provide a traveling transmission mechanism in which the installation portion of the front wheel transmission is made compact in size while eliminating the rear center state of the traveling vehicle body.

According to the present invention to achieve the above object, a main transmission mechanism having an input shaft that receives power from the engine in front of the vehicle body through the main clutch mechanism and a first transmission shaft installed in parallel with the input shaft and electrically connected; A rear transmission installed at a rear of the vehicle body to receive power from the first transmission shaft; Front wheel driving means installed in parallel with the first transmission shaft and including a second transmission shaft that receives power from the rear transmission; A front wheel transmission configured to transfer power from the second transmission shaft to a standard driving state for driving the front wheels at substantially the same speed as the rear wheels and a high speed driving state for driving the rear wheels at a higher speed than the rear wheels, and to transfer the front wheels to the front wheels; There is provided a traveling transmission mechanism of a tractor which consists of a front wheel transmission case for accommodating the main transmission mechanism, front wheel drive means and front wheel transmission, wherein the front wheel transmission case is directly connected to the rear and bottom portion of the main clutch case.

According to the above configuration, since the front wheel transmission is accommodated in the front wheel transmission case connected to the rear side of the main clutch case, the attachment position becomes the entire body side and moves the center position of the entire vehicle body forward in comparison with the case where it is attached to the front of the rear transmission. Therefore, since the center moves to the front side, it is possible to reduce or eliminate the weight of the counterweight installed at the front end of the vehicle body, reduce the weight of the whole body and simplify the body frame structure.

Compared with the case where the front wheel transmission is installed in the front axle case for the same purpose, since the positional relationship between the required reduction mechanism and the front wheel transmission is reversed between the two, the transmission torque is not large in this case, so that the size of the front wheel transmission can be avoided.

In general, the front-wheel drive and the main powertrain are not directly connected, so they must be housed in separate cases and connected. In this case, each outer wall exists at the connection part of both cases so that the gear of the front-wheel drive and the gear of the main drive are separated by the thickness thereof, but in the case of the present invention, the front-wheel drive and the main drive are accommodated in the same case. The gears can be approached as far as possible, allowing the front-wheel transmission to be close to the main powertrain. Therefore, even if the front wheel transmission is located below the main transmission, the ground clearance can be increased because it is located close to the main transmission, and the installation position of the front transmission is changed by setting the transmission shaft lower from the main transmission to the rear derailleur. Can be avoided.

In the preferred embodiment of the present invention, since the front wheel transmission is accommodated below the main clutch mechanism operation clutch sleeve, the empty space below the clutch sleeve can be filled.

Since the efficient use of the empty space under the clutch sleeve increases the efficiency of space use, and when the front wheel transmission case is installed on the rear side of the main clutch case, the front wheel transmission case protrudes rearward, since the front wheel transmission case is arranged to be connected back and forth to the required space. In this case, since the front wheel transmission is accommodated in the main clutch case side, the length of protruding rearwards is shortened, so that the length of the electric shaft extending from the front wheel transmission to the front axle case is shortened.

In a preferred embodiment, the input shaft and the first transmission shaft are installed in the up and down direction, and the transmission shaft that transmits power from the main clutch to the rear transmission is not the output shaft from the main clutch but the transmission shaft located below the transmission shaft and the rear transmission side. The drive shaft connecting the input shaft can be installed lower than the case in which the output shaft of the main clutch and the input shaft on the rear derailleur side are directly connected, thereby lowering the deck position of the control driver located above the drive shaft. In addition, since the deck position is low, it is easy to ride, and the driver's seat is also at a low position, so the height of the body is lowered.

In another embodiment of the present invention, a steering gear box for supporting the pitman arm and a mechanical mechanism for connecting the pitman arm and the front wheel transmission to switch the front wheel transmission to a high speed driving state according to a steering operation of a predetermined amount or more. A link mechanism is further included, and the steering gear box is installed in the vicinity of the engine.

The pitman arm operated according to the steering operation is disposed adjacent to the front wheel shifting device so that both can be connected by a mechanical link mechanism, and switching to a high-speed drive state by a predetermined amount or more of steering operation is simplified, and the mechanical connection mechanism is also fitted by the pitman arm. Since the arm and the front wheel transmission are disposed adjacent to each other, a simple connector such as a link plate or a link arm may be used.

In another preferred embodiment of the present invention, a steering gear box and a front wheel transmission case respectively supporting the Pitman arm connected to the mechanical link mechanism and the operation arm of the front wheel transmission are directly connected, and the steering gear box is installed in the main clutch case. Compared with one case, it is easier to assemble the relative positional relationship between the Pitman arm and the operating arm as designed.

Therefore, if the attachment dimension of the pitman arm to the steering gear box and the attachment arm of the operation arm to the front derailleur case are strictly managed, attach the steering gear box to the front derailleur case and then use the mechanical link mechanism to secure the pitman arm and the operation arm. No fine adjustment of assembly is necessary when connecting. Therefore, in the front-wheel transmission which must be switched to the high-speed drive state when the steering operation exceeds a predetermined amount (40 °), the switching timing change to the high-speed drive state caused by the mismatch caused by the connection error of the pitman arm and the operation arm is prevented. Thus, the driving operability is improved.

In another embodiment of the present invention, the front wheel shifting device is a speed increasing mechanism, so that the output to the front axle case is higher than in the related art. Therefore, the shaft torque is reduced, so that the electric gear in the front axle case can also use a small diameter, and the front axle case that accommodates it is also miniaturized. The miniaturization of the front axle case increases the ground clearance and is less affected by ground obstacles.

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

As shown in FIG. 1, the steering unit 4 provided with the engine 1, the radiator 2, the steering wheel 3 at the rear thereof, the rear transmission 5 at the rear thereof, and the cultivation device are shown. The link mechanism 6 which connects up and down is provided, and the front and back drive wheels 7 and 8 are provided in the traveling vehicle body in which these and the instrument are mounted, and a four-wheel drive agricultural tractor is comprised.

As shown in FIG. 2 and FIG. 3, the main clutch case 10 is connected to the rear of the engine 1, and the front wheel transmission case 11 in which the front wheel transmission 9 is built into the rear is fixed. do. The steering gear box 13 supporting the steering wheel operating shaft 12 is fixed to the upper surface of the front wheel transmission case 11.

The main clutch mechanism 14 is a dry end plate clutch, which includes a clutch disk 57, a pressure plate 58 for pressing the clutch disc 57 that operates together with the flywheel 55, and a clutch sleeve located behind the pressure plate 58. 50, the operation arm 52 which pushes the clutch sleeve 50 to the diaphragm spring 51, and retracts the press plate 58 from the press action which presses the clutch disc 57 is carried out. The sleeve guide 53 in which the clutch sleeve 50 is slidably enclosed surrounds the input shaft 15 leading to the front transmission 9 and a boundary boss between the clutch case 10 and the front transmission case 11. Is kept inserted. Since the oil seal 54 which prevents leakage of oil from the front wheel transmission case 11 is inserted in the wall surface of this sleeve guide 53, the sleeve guide 53 is clutched independently without disassembling the front wheel transmission case 11. It can be disassembled from the side.

The input shaft 15 protrudes from the main clutch case 10 and is supported in the front wheel transmission case 11. The case 11 has a first transmission shaft 17 located below the input shaft 15 and transmitting power to the input shaft 16 on the rear transmission 5 side, and again from the rear transmission 5 at the lower portion thereof. The second electric shaft 18 which receives the front wheel driving force, the third electric shaft 19, and the third electric wheel which are held so that one end can rotate relatively freely with the shaft center coinciding with the inner end of the second electric shaft 18. Fourth transmission shafts 21 are arranged, respectively, from the lower portion of the coaxial to the front axle case 20. This rear transmission 5 has a main transmission mechanism, a secondary transmission mechanism, a forward reverse switching mechanism and a differential mechanism to transmit the shifted power to the second transmission shaft 18. Power is transmitted to the first transmission shaft 17 through a gear transmission mechanism comprising a first gear 22 attached to the input shaft 15 and a second gear 23 attached to the first transmission shaft 17. The power transmitted from the first transmission shaft 17 to the rear transmission 5 is transmitted to the second transmission shaft 18 as a front wheel driving force. On the other hand, the relay transmission member 26 in which a pair of small and large pairs of the third gear 24 and the fourth gear 25 are integrally formed with respect to the first transmission shaft 17 using a known device such as a sleeve bearing or a sliding bearing, for example. It is installed so as to rotate relatively, the friction multi-plate clutch 27 is installed on the third transmission shaft 19, the fifth gear 28 is integrally formed on the inner end of the second transmission shaft (18).

The clutch 27 has a clutch body 30 having a sixth gear 29 which is always engaged with the third gear 24, and a rotating member 31 that cooperates with the clutch body 30 to support the friction plate. The piston 32 is in contact with the friction multi-plate and has a clutch sleeve 33 having an outer gear formed at one end and engaging or detachable with the inner gear 18A of the second transmission shaft 18 at the other end. In addition, the seventh gear 34 and the eighth gear 35 are splined to the front end of the third transmission shaft 19 and the rear end of the fourth transmission shaft 21, respectively, so that power is applied to the fourth transmission shaft 21. Delivered. Therefore, when the clutch sleeve 33 is engaged with the inner gear 18A of the second transmission shaft 18, the power transmitted to the second transmission shaft 18 is transferred to the third transmission shaft 19 through the clutch sleeve 33. And the front wheel 7 and the rear wheel 8 are driven at a substantially constant speed, and the clutch wheel 33 is operated to the opposite side to operate the clutch 27 to be transferred to the second electric shaft 18. Power is transmitted to the third transmission shaft 19 through the relay transmission member 26 and the clutch main body 30, so that the front wheel 7 is driven at a high speed with respect to the rear wheel 8.

The operation mechanism for the front wheel transmission 9 will be described below. As shown in Figs. 4 to 6, this operation mechanism is integrally assembled in a cassette manner and detachably attached to the side of the front wheel transmission case 11. The operating shaft 37 in the lateral direction is rotatably supported with respect to the attachment case 36 of the operating mechanism, and is fixed to the Pitman arm 38 and the operating shaft 37 supported by the steering gear box 13. The operation arm 39 is connected to the link plate 40 which is a mechanical link mechanism, and the clutch 27 is operated in accordance with the steering operation. A support holder 41 is supported on the inner end of the operation shaft 37 so that the operation shaft 37 can rotate, and a sliding rod 42 between the support holder 41 and an inner wall of the attachment case 36. Is provided, the sliding rod 42 can slide in the direction of the axis (Y) orthogonal to the axis (X) of the operating shaft (37). One end of the sliding rod 42 is attached to the rotary roller 44 through the support member 43, the cam plate which is rotatable integrally with respect to the operation shaft 37 and slides in the direction of the axis (X) ( 45 is splined. As shown in FIG. 6, the cam plate 45 rotates about the axis X so that the sliding rod 42 moves forward and backward in the direction of the axis Y. The cam surface which consists of the large diameter part 45a and the small diameter part 45b which act on 44 is formed. As shown in FIGS. 4 and 5, the distal fork acting on the clutch sleeve 33 of the front wheel transmission 9 at the opposite end to which the support member 43 of the sliding device 42 is mounted ( 46 is installed and displaced by the first spring 47 between the support holder 41 and the distal fork 46 and the second spring 48 between the sliding rod 42 and the distal fork 46 base. The fork 46 is held in a neutral position and engaged with the cam plate 45 and the rotary roller 44 to limit movement.

As shown in FIG. 6, when the steering operation amount is equal to or less than a predetermined amount (40 ° or less of rotation angle), the small diameter portion 45b of the cam plate 45 is in a position corresponding to the rotation roller 44. In this case, the rotation roller 44 ) And the small diameter portion 45b are separated from each other so that the displacement fork 46 is located on the right side in FIG. 4 to engage the clutch sleeve 33 with the inner gear 18A so as to be in the front wheel standard driving state. Further steering operation from this state causes the Pitman arm 38 to swing so that one of the two large diameter portions 45a acts on the rotary roller 44 to move the sliding rod 42 to the left of FIG. 4 and to engage the clutch 27. To activate high speed drive. The cam plate 45 is provided with a displacement fork, and the cam plate 45 is moved in the direction of the axis X of the operating shaft 37 to retreat to a position corresponding to the rotary roller 44 to perform steering operation. Even if the cam plate 45 does not move the sliding rod 42, the said displacement fork becomes a mechanism which limits the high speed drive state.

On the other hand, as shown in FIG. 2, the front wheel transmission case 11 and the rear transmission case 5 are connected by a box-shaped sheet metal frame 63, and the transmission shaft 64 for connecting the front and rear transmissions in the frame 63 is formed. 56) is installed. Here, the bottom face of the front and rear transmission becomes the lowest position, and the main clutch case 10 and the engine 1 are positioned upwards, thereby increasing the ground height of the tractor.

In another embodiment, the steering gear box 13 and the front wheel transmission case 11 may be one case, and the mechanical link mechanism 40 may be another wire or the like.

Claims (7)

A main shaft having an input shaft 15 which receives power from the engine 1 on the front of the vehicle body via the main clutch mechanism 14 and a first transmission shaft 17 installed in parallel with the input shaft 15 and electrically connected thereto. Power mechanism; A rear transmission (5) installed at the rear of the vehicle body to receive power from the first transmission shaft (17); Front wheel drive means installed in parallel with the first transmission shaft (17) and including a second transmission shaft (18) receiving power from the rear transmission (5); Shifting to a standard driving state for receiving power from the second electric shaft 18 and driving the front wheels 7 at substantially the same speed as the rear wheels 8, and a high speed driving state for driving the rear wheels 8 at a higher speed than the rear wheels 8; A front wheel transmission 9 configured to transmit the front wheel 7 to the front wheel 7; A tractor comprising a front wheel transmission case 11 for accommodating the main transmission mechanism, a front wheel drive means, and a front wheel transmission 9, wherein the front wheel transmission case 11 is directly connected to the rear lower portion of the main clutch case 10. Running power mechanism. 2. The traveling transmission mechanism of a tractor according to claim 1, wherein said front wheel shifting device is provided below a clutch sleeve (50) for coupling and separating said main clutch mechanism (14) and said input shaft (15). The tractor drive transmission mechanism according to claim 1, wherein the electric connection between the input shaft (15) and the first transmission shaft (17) comprises a gear mechanism (49). The relay transmission member 26 according to any one of claims 1 to 3, wherein the relay transmission member 26 has a pair of gears 24 and 25 installed in the front wheel transmission device so as to be relatively rotatable to the first transmission shaft 17. A first transmission state in which the speed of the third transmission shaft 19 and the second transmission shaft 18 coaxially arranged with the second transmission shaft 18 are transmitted to the third transmission shaft 17 at a constant speed; And installed in the third transmission shaft 19 to select a second transmission state that transmits the speed of the second transmission shaft to the third transmission shaft 19 while being shifted through the relay transmission member 26. The traveling transmission mechanism of the tractor which includes the clutch mechanism 27. 5. The traveling transmission mechanism of claim 4, wherein the third transmission shaft (19) is electrically connected to the fourth transmission shaft (21) connected to the front wheel through a speed increase mechanism. A steering gear box (13) for supporting the Pitman arm (38); And a mechanical link mechanism 40 for connecting the Pitman arm 38 and the front wheel transmission 9 so as to switch the front wheel transmission 9 to a high speed driving state according to a steering operation of a predetermined amount or more. ; The drive transmission mechanism of the tractor in which the steering gear box 13 is arranged near the engine 1. The tractor drive transmission mechanism according to claim 6, wherein the steering gear box (13) is directly connected to an upper surface of the front wheel transmission case (11).

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