JPS5835885B2 - tractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a transmission case and a clutch housing portion of a tractor that includes a hydraulic clutch type transmission in its transmission.

Hydraulic clutch type transmissions have the advantage of being able to change gears by switching a hydraulic control valve while power is still being transmitted, without engaging or disconnecting the main clutch device.

However, it is necessary to send pressure oil through oil passages to the hydraulic clutch device mounted on the hydraulic clutch shaft, and as the number of hydraulic clutch devices increases, the number of oil passages increases, making the configuration complicated. In addition, there is a problem that assembly is complicated.

Particularly during assembly, it is necessary to seal the oil passage, and in order to apply sealing liquid to the sealing part, and to ensure that the sealing surfaces are in close contact, parts related to the oil passage must be removed externally before being assembled into the tractor. The means to facilitate assembly is to make a mechanical structure, perform precise assembly, and then incorporate it into a tractor.

Parts related to oil passages include pumps, hydraulic control valves, transfer tubes, hydraulic clutch shafts, hydraulic clutch devices, etc., but in particular, transfer tubes, hydraulic clutch shafts, hydraulic clutch devices, etc. that are assembled in the transmission case are other mechanical components. It is best to assemble it in one place and then attach it to the tractor.

In the present invention, in order to fix these oil passage parts as a semi-mechanical product, a side cover B for closing the front opening of the transmission case is used, and a transfer pipe, a hydraulic clutch shaft, and a hydraulic clutch device are attached to this side cover. It is integrated.

Along with this, the loose fitting gear of the hydraulic clutch device is also included in the semi-mechanical products, and the drive side gear that meshes with this loose fitting gear, and in the case of a transmission that includes reverse movement, the reverse idle gear, etc. It is also desirable to integrate them.

The present invention includes a transmission case A and a clutch housing 6.
The side cover B, which partitions the two with an oil-tight structure, is used as the rear wall of the clutch housing 6 and the front wall of the transmission case A, and the end of the hydraulic clutch shaft on which the hydraulic clutch device is mounted on the side cover B is used as the rear wall of the clutch housing 6 and the front wall of the transmission case A. Support the bearing and remove the clutch housing 6 from the side cover B.
A transfer tube 75 is fitted to the protruding part of the hydraulic clutch shaft inward, and the transfer tube 75 is attached to the clutch housing side of the side cover B, and the transfer tube 75 is attached to the clutch housing side of the side cover B. The idle gear 65 is mounted as one unit and supported in a removable manner.This allows parts related to the oil passage to be assembled separately on the side cover in a mechanical state.
At that time, the back idle gear can also be installed, and by installing the side cover into the transmission case from the front, there is no need to assemble the oil passage inside the transmission case or the bank gear.

Hereinafter, a detailed description will be given based on the embodiments shown in the drawings.

Referring to Figure 1, two front wheels 1, a handle 3, a seat 4
The engine E is mounted on the front part of the fuselage, which has a lift arm 5, etc., and the lower part of the fuselage is connected to the clutch housing 6, the transmission case A1, and the rear case 8 from the engine shift part 8 toward the rear. Axles 9 are protruded from both sides near the rear of the case 8, and a rear wheel 10 is mounted on each of the axles 9,
One PTO shaft is installed behind the rear case 8.

The front part of the main clutch shaft 12 in the clutch housing 6 is connected to a clutch 13 connected to the engine E side, and the clutch is configured to be actuated to disengage by suppressing an actuating body 15 actuated by depression of the clutch pedal 14. A potbell-shaped opening 16 is formed in the center of the rear wall 6' of the clutch housing 6, and a front wall 17 of the transmission case A is formed in the rear wall 6' of the clutch housing 6.
Similarly, a potbell-shaped opening 18 is formed in the opening 18, and the front and rear surfaces of the side cover B are joined to the rear surface of the rear wall portion 6' and the front surface of the front wall portion 17. As shown by solid lines in FIG. 5, a large number of long groove-shaped oil passages 19 with a U-shaped cross section are formed by extending and bending them at the part that joins with the rear wall part 6', and the front wall is formed on the rear surface of the side cover B. The fifth part is connected to the part 17.
As shown by dotted lines in the figure, a large number of long groove-shaped oil passages 19' with a U-shaped cross section are formed by extending and bending each, and bearings 20 and 20' are fitted into the through holes at the upper and lower positions of the side cover B, respectively. do.

On the upper part of the front wall part 17 of the mission case A, there is a clay wall part 21.
A thick wall portion 22 is formed, and within the thick wall portion 22, an oil path 23 that connects to the oil paths 19' and 19 is formed by bending and extending from the upper surface of the earth wall portion 21, and the rear opening of the mission case A is formed. 24 is provided so that the front wall 25 of the rear case 8 is aligned with the front wall 25 of the rear case 8 for long-distance fixing, and a support wall 27 that partitions the front chamber 26 and the rear chamber 26' is integrally formed inside the mission case A. Bearings 30, 30' are fitted into the through holes at the upper and lower positions of the support wall 27, and a through hole 31 is formed in the lower part of the support wall 27, and a through hole part 32 is formed in the upper part.

Bearings 33 and large bearings 33' are fitted in the upper and lower positions of the front wall portion 25 of the rear case 8, and bearings 36, 36' and 33' are fitted in the upper and lower positions of the partition wall 34 and the rear wall 35 at the rear of the rear case 8, respectively. 3737' is fitted, a hydraulic case 38 is mounted on the upper part of the rear case 8, and a low-pressure pipe 39 is provided at the front lower part of the rear case 8 from the inside to the outside to communicate with the pump case 59.

C indicates a main shaft, and the main shaft C is inserted from the front opening 18 side and assembled, and is supported from the tip to the rear by the bearings 20, 30, 33', respectively, and the front chamber 2
6, four gears 40a, 40b each having a different diameter are disposed on the main shaft C portion.

40c and 40d are fitted at intervals so as to be locked in the rotational direction, and a boss 5 is provided at the main shaft C portion in the rear chamber 26'.
Gears 51a, 51b, 51c, 5 that are loosely fitted into the boss 50 and become heavier at regular intervals in the front and back direction of the boss 50.
1d are integrally formed, and the rear end portion of the shaft C extends into the rear case 8.

Inside the clutch housing 6, the main clutch shaft 1
A pump shaft 52 is connected to the rear end of 2 via a coupling 53, and the front end of the main shaft C protruding forward from the side cover B is brought into contact with the pump shaft 52, so that the main shaft C and the pump shaft 52 are connected to each other.
The pump case 56 of the pump gear 54 is connected by a spline engagement 55 with the pump gear 54 astride the pump gear 54.
Align it with the front of side cover B and fix it with bolt 56'.
A discharge hydraulic pressure port 57 of the pump case 56 is communicated with a part of the oil passage 19' that communicates with a part of the oil passages 23 group, and an oil passage 59 is formed in the side lid B, which communicates with the suction port 58 of the pump case 56. At the same time, a cap 60 communicating with the oil passage 59 is fixed to the side of the side cover B, and the low-pressure vibro 1 communicatively connected to the cap 60 is extended and connected to the low-pressure pipe portion 39.

D is a latch shaft parallel to the main shaft C, and the front and rear portions of the clutch shaft are connected to the bearings 20'.

30', and a hydraulic clutch type transmission device F is mounted on the clutch shaft, and this device F has four gears 62a, 62 of different diameters spaced apart from each other on the clutch shaft.
b, 62c, and 62d are loosely fitted through the bearing 63,
A reverse idle gear 65 is cantilevered on a support shaft 64 mounted on the side lid B, and the gears 40a and 62
The gear 65 is meshed with the gear 40b, 40c, 4
Gears 62 b , 62 c , and 62 d are engaged with 0ct, respectively, and a transmission body 67 having back-to-back cylinder parts 66 a and 66 b is fitted between the gears 62 a and 62 b via a key 68 around the clutch shaft. The actuators 69, 66b are fixed to both cylinder parts 66a, 66b, respectively.
69' and both cylinder parts 66a.

66b and both gears 62a, 62b are interposed a large number of hydraulic clutch plates 70, 70', which are operated by pressure by actuators 69, 69', respectively, to constitute hydraulic clutches for forward 1st speed and reverse. , both gears 62 c s
62 Cylinder part between d 66 c s 66
d, transmission body 67', key 68, actuator 69
a, 69'a, hydraulic clutch plate 70a, 70
The gear 62c side is configured as a hydraulic clutch for the second forward speed, and the gear 62b side is configured as a hydraulic clutch for the third forward speed.

Furthermore, the tip of the clutch shaft extending from the front surface of the side cover B into the clutch housing 6 has four circumferential grooves 71a, 71b, and 71c spaced apart at regular intervals.

71d, and four oil passages 72 communicating with each circumferential groove are formed extending in the axial direction inside the clutch shaft, and are formed on the transmission body 67 toward the cylinder parts 66a and 66b, respectively. oil passages 73, 73' and cylinder part 66c
, 66d, oil passages 74, 74'l formed in the transmission body 67', respectively, are configured so as to communicate with the four oil passages 72, and four circumferential grooves 71a, 71b.
, 71 c and 71 d, a one-sided blind transfer tube 75 is fitted to the end of the clutch shaft in the portions 71 c and 71 d, and the transfer tube 75 is joined to the front surface of the side cover B and tightly fixed with bolts 76 . B oil passages 19, 19' and circumferential grooves 71a to 71
A plurality of oil passages 77 are formed in the transfer tube 75, and a space 78 between the clutch shaft tip and the end face of the transfer tube 75 is configured to communicate with a drain oil passage 79.

A rear end portion of the clutch shaft is provided to protrude into the rear chamber 26', and a gear portion 80 is formed in that portion, and the gear 51a is meshed with the gear portion 80, and a shaft center portion inside the gear portion 80 is formed. A shaft hole 81 is formed in the shaft hole 81, and the front end of the traveling drive shaft G is rotatably supported in the shaft hole 81 via a needle bearing 82, and the rear end is supported by a large bearing 33'. Align the axes of the clutch shaft and travel drive shaft G, and rotate the main shaft C.
A transmission gear 84 is configured to extend parallel downwardly, and is spline engaged 83 with the traveling drive shaft G. A transmission gear 84 is provided in the gear portion 80 so as to be selectively engaged with the dog engagement 85 and the gear 51b, and is engaged with the spline at the rear thereof. A gear type transmission device H is constructed by providing a two-stage transmission gear 84' having the structure 83 so as to be selectively meshed with the gears 51c and 51d.

Further, both gears 84 and 84' are provided so that they can be shifted by both shifter forks 87 and 87' which are operated from a speed change lever 861 provided above the rear chamber 26'.
A spiral gear 88 is formed at the rear end of the travel drive shaft G protruding into the rear case 8, and the gear 88 drives a differential device 89 to drive an intermediate shaft 91' having a brake section 90.
, 91' are configured to transmit gears to the axle 9.

The front end of a transmission shaft 11' is connected to the rear end of the main shaft C which is supported by the bearing 33 and extended into the rear case 8 by a coupling 92, and the transmission shaft 11' is supported by bearings 26 and 27. A movable two-stage gear 94 is spline-engaged with the transmission shaft 11' by a shifter fork 93, and a second-stage gear 94' is loosely fitted.
A PTO shaft 11 supported by bearings 36' and 37' is provided below the transmission shaft 11' so as to protrude rearward from the rear wall so that power can be taken out, and the PTO@11 is selectively engaged with a two-stage gear 94. A three-stage gear 94a is loosely fitted, and one of its gears is always meshed with one of the two-stage gears 94', and the other one of the two-stage gears 94' is fitted with the PTO shaft 11.
The gear 94b that is loosely fitted into the PTO shaft 11 is always engaged, and the transmission gear 94c spline-engaged with the PTO shaft 11 can be shifted by the shifter fork 93'.
and a dog clutch type engagement 9 that can be selectively applied to the gear 94b.
5a.

95b, both shifter forks 93
, 93' are configured to be freely operable by an operating lever 96.

K indicates a hydraulic control valve having an accumulator 97, the entire control valve is mounted and fixed on the machined surface of the upper surface of the upper wall portion 21 of the mission case A, and a spool S is provided so as to be movable and operable by a shifter M. An operating rod 98' for operating the shifter M extends upward and is provided so that the operating rod 98' can be operated by a lever 98 disposed near the handle 3. A large number of oil passages 99 are formed from the side to the hydraulic clutch type transmission F for three reverse and forward speeds and a drain, and each oil passage 99
are connected to the respective oil passages 23 in the thick wall portion 22, and a portion of the drain oil passage 99' is configured to communicate into the front chamber 26 of the mission case A through the earth wall portion 21.

In the tractor with the above configuration, the clutch pedal 14
main clutch shaft 1 by connecting clutch 13 without depressing
2 is rotated, the main shaft C rotates due to the connection via the pump gear 54, and the rotation of the pump gear 54 drives a hydraulic pump in the pump case 56, and the oil accumulated in the rear case 8 is transferred to the low pressure pipe section. High-pressure oil is drawn into the pump gear 54 side from 39 through the vibro 1, the mouthpiece 60, and the oil passage 59, and is discharged from the inside of the pump case 56. When the spool S is in a neutral state, it flows into the front chamber 26 of the transmission case A through the drain oil path 99', and becomes lubricating oil in the front chamber 26, and also lubricates the support wall 27.
It flows from the through hole 31 to the rear chamber 26', further into the rear case 8, and from the low pressure pipe section 39 to the pump case 5.
Circulate to the 6th side.

When the driver operates the lever 98, the hydraulic clutch type transmission device F can be operated to shift between reverse and three forward speeds, and this shift operation can be used as a main shift and a sub-shift to change the number of gears to 12 forward and reverse. It is possible to drive 10 rear wheels in 4th gear.

That is, in the gear shifting operation of the hydraulic clutch type transmission device F, the spools S are moved to four stages using the shifter M by operating the lever 98. By operation, each oil passage 99 is connected to the oil passage 23 of the thick wall portion 22 and the side lid B.
The oil is sent under pressure to the circumferential grooves 71a to 71b of the clutch shaft through the oil passages 19-19 and the oil passage 77 of the transfer tube 75, and is sent from each of the circumferential grooves 71a to 71d to the communicating oil passages 72 in the clutch shaft. From the oil passages 73, 73', 74° 74' to the cylinder parts 66a, 66b, 66c.

It can be operated to supply pressurized oil into 66d.

Therefore, when the spool S is operated in reverse, the oil path 73
High-pressure oil from the actuator 69 activates the hydraulic clutch plate 70 to connect the gear 62a and the transmission body 67, so that the gear 40a rotating with the main shaft C is connected to the idle gear 65, the gear 62a, the hydraulic clutch plate 70, Transmission body 67
When the clutch shaft is rotated backward through
High pressure oil from 74, 74' is applied to actuators 69', 6
9a, 69'a to operate the hydraulic clutch plates 70', 70.
a, 70'a, and gears 62b, 62c, 6
A gear 40b rotates together with the main shaft C by connecting the gear 2d and the transmission body 67, 67'.

40c, 40d are gears 62 b s 62 c, 62
d. The clutch shaft can be rotated forward through the hydraulic clutch plates 70', 70a, 70'a transmission bodies 67°67' to perform the respective speed change operations due to the difference in gear diameter.

In addition, in a speed change operation of the gear type transmission device H, when the speed change gear 84 is moved by the shifter fork 87 by operating the speed change lever 86 and dog-engaged 85 with the gear portion 80 of the clutch shaft, the clutch shaft and Directly connected to the traveling drive shaft G, it is possible to perform transmission operation for one speed forward and backward, and the transmission gear 84 can be selectively engaged with the gear 51b, and the two-speed transmission gear 84' can be selected as the gear 51c, z, 51d. A 3-speed transmission operation can be performed by selectively engaging and engaging the clutch shaft, and a total of 4-speed transmission operations can be performed from the clutch shaft to the traveling and drive shafts GI.

In total, the rear end spiral gear 88 of the driving shaft G, which is rotated at a variable speed of 4 reverse speeds and 12 forward speeds, rotates a differential device 89 to drive both rear wheels 10 degrees 10, and the vehicle can travel.

In addition, when a working machine is installed at the rear of an agricultural tractor and power is transmitted to the working machine from the PTO shaft 11, the shifter fork 93 moves the transmission shaft 11' which is rotating at the same time on an extension of the main shaft C. When the second speed gear 94 is moved and selectively engaged with the third speed gear 94a, and the shift engaging body 94c is moved and operated by the shifter fork 93' to engage the gear 94b in a dog clutch type engagement 95b.
3rd gear 94a, 2nd gear 9
4′.

Two sets of rotations P through the gear 94b and the transmission meshing body 94c.
The signal is transmitted to the TO shaft 11, and when the transmission meshing body 94c is engaged in the dog clutch type engagement 95a with the third gear 94a, 2
From the variable speed gear 94 to the third gear 94a, the variable gear mesh 94c
The rotation of the other 2 speeds is transmitted through the PTO for a total of 4 speeds.
It is possible to change the axis.

Note that when the clutch pedal 74 is depressed to disengage the clutch 13, the pump and all rotations stop.

In such an overall configuration, the present invention particularly relates to the side lid B.

Even in conventional tractors, the front wall of the transmission case is closed, but this is closed by a wall that is built integrally with the transmission case, and is separated from the mission case A by a removable side cover. There is no such thing.

In particular, in the present invention, the side cover B can be removed separately from the transmission case, and the side cover B supports the hydraulic clutch shaft and the main shaft C1 transfer tube 75.

Therefore, on the side of this side cover B, the main shaft C, the hydraulic clutch shaft, the fixed gears, loosely fitted gears, and hydraulic clutches on these shafts are arranged, and with the gears engaged, the mission case front wall 17 is installed.
Assembly is completed by inserting these through the potbell-shaped opening 18, fitting the rear ends of the main shaft C and the hydraulic clutch shaft into the bearing holes of the partition wall 34, and fixing the side cover B to the front surface of the transmission case A. It ends.

In contrast to these configurations, a further important part of the present invention is that the back idler carrier is also integrally supported by the side lid, so that it can be constructed and assembled at the same time.

With this configuration, the oil passage related parts and surrounding parts can be concentrated in the side lid, and these parts can be precisely assembled into a working state and then assembled into the transmission case. It becomes possible.

As described above, the present invention mounts an engine E in the front part of a machine body having two front wheels 1, a handle 3, a seat 4, a lift arm 5, etc. 6. The side cover B, which is constructed by connecting the transmission case A and the rear case 8 and partitions the transmission case A and the clutch housing 6 with an oil-tight structure on the transmission case side, is connected to the rear wall of the clutch housing 6 and the transmission case A. The hydraulic clutch shaft is also used as the front wall of the clutch housing 6, and the end of the hydraulic clutch shaft on which the hydraulic clutch device is mounted and the main shaft C are supported by bearings on the side lid B. A transfer tube 75 is fitted into the protrusion of the side cover B, and the transfer tube 75 is attached to the clutch housing side of the side cover B, and the reverse idle gear 65 in the mission case A is attached to the side cover B as an integral part of the mission case. Since the installation for A is removably supported, the transfer pipe 75, which is a hydraulic-related part for sending pressure oil to the hydraulic clutch device, and the hydraulic clutch shaft are attached to the side cover for the front wall of the transmission case. Pressure oil can also be sent from the hydraulic pump and hydraulic control valve outside of mission case A to the hydraulic clutch device inside mission case A through this side cover. The hydraulic clutch device can be fixed to the hydraulic clutch shaft, and the loosely fitted gear attached to the hydraulic clutch device can be assembled on the hydraulic clutch shaft. The back idle gear 65 between the loosely fitted gear and the fixed gear on the main shaft is also assembled integrally with the side cover, and is inserted into the bell-shaped opening 18 of the front wall 17 of the transmission case. It can be inserted from the beginning and finally assembled.

Therefore, the hydraulic parts for the hydraulic clutch device can be put together in the side cover to form a working system, and when forming a working system, the oil passages must be sealed, the joint surfaces must be sealed, and the delicate parts of the hydraulic clutch shaft and transfer tube must be sealed. Since it was possible to carefully assemble the parts and fit them together before assembling them into the transmission case, precise assembly was possible, and subsequent assembly into the transmission case was also made easier.

[Brief explanation of the drawing]

FIG. 1 is a side view of the tractor of the present invention, FIG. 2 is a skeleton diagram showing the power transmission system, FIG. FIG. 5 is an enlarged side sectional view of the front part of the case, and FIG. 5 is a front view of the side lid of the front side of the transmission case. A...Mission case, B...Side lid, D...Hydraulic clutch shaft, E...Engine, F...Hydraulic clutch type transmission, 1...Two front wheels, 3... handle,
4... Seat, 5... Lift arm 6... Clutch housing sink 8... Rear case, 65... Back idle gear 67... Hydraulic clutch, 75... Transfer tube.

Claims (1)

[Claims] 1 An engine E is mounted on the front part of a fuselage having two front wheels 1, a handle 3, a seat 4, a lift arm 5, etc., and from the engine E toward the rear, the lower part of the fuselage is connected to the clutch housing 6 and the rear of the transmission case A1. Consists of case 8 connected in series, transmission case A and clutch housing 6
Side cover B that partitions the transmission case side with an oil-tight structure between
is used as both the rear wall of the clutch housing 6 and the front wall of the transmission case A, and the end of the hydraulic clutch shaft on which the hydraulic clutch 67 is mounted and the main shaft C are supported by bearings on the side lid B. A transfer tube 75 is fitted into the protrusion of the hydraulic clutch shaft into the clutch housing 6, and the transfer tube 75 is attached to the clutch housing side of the side cover B. Furthermore, the transfer tube 75 is attached to the side cover B to the transmission case A. This tractor is characterized in that a reversing idle gear 65 is detachably supported on the transmission case A as one unit.