JPH0684132B2 - Transmission structure of tractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a hollow shaft for transmitting a driving force and a hollow shaft for transmitting a driving force between a clutch housing and a mesh case, which are connected to each other in the front and rear. PTO penetrating the shaft
The present invention relates to a transmission structure of a tractor which is made to operate by each axis of a system.

[Conventional technology]

The reason why the shaft of the traveling system is a hollow shaft as described above and the shaft of the PTO system is provided by penetrating the hollow shaft is that the traveling system shaft and the PTO system shaft are differently formed by the main clutch operation. This is to enable driving, and when the main clutch is a dual clutch, the drive of the traveling system axis is stopped by the first-stage cutting operation of the main clutch, and the PTO-system axis is stopped by the second-stage cutting operation. The driving is also stopped. Further, in the case where the PTO system clutch is provided on the lower side of the PTO system transmission path separately from the main clutch (for example, see Japanese Utility Model Laid-Open No. 56-97128),
The main clutch is said to be able to stop driving only the drive shaft, and the PTO shaft is directly connected to the engine.

By the way, in the transmission structure of a tractor that requires various specifications, various technologies have been proposed for providing a forward / reverse switching mechanism or a vehicle speed high / low switching mechanism by utilizing a rear space in a clutch housing that houses a main clutch in the front end. There is.

These are roughly classified into those in which a gear case containing the above-described switching mechanism (hereinafter, referred to as a "transmission device because shifting between forward and reverse is also a gear shift") is incorporated in the clutch housing (for example, the actual open sho 59-37131). No.
A structure in which a support frame or a bearing frame for supporting the transmission is provided in the clutch housing (for example, the actual open sho-58-
22557 gazette)).

[Problems to be solved by the invention]

Among them, the one using the shift case is heavy and it is difficult to assemble it into the clutch housing, and if the specification of the transmission in the shift case is changed, the size of the shift case is relatively large and costly. It has to be a collection.

A structure using a support frame or a bearing frame is lightweight and easy to handle, and at a considerably lower cost than a structure using a transmission case, the structure proposed so far has a single support frame and a rear wall of the clutch housing. Since the structure is used to support the transmission or its multiple shafts, it is not possible to easily deal with the specification change of the transmission, and if the specification change is made, the clutch with a different structure of the rear wall is used. Often the need to use a housing arises.

Therefore, the present invention provides a tractor transmission structure that is compatible with transmissions of various specifications with a structure using a support frame or a bearing frame, and is extremely easy to install in the clutch housing, and overcomes the drawbacks of the conventional ones. Is what you are trying to do.

[Means for solving problems]

Therefore, according to the present invention, the traveling drive force is transmitted between the clutch housing 1 and the transmission case 2 connected in the front and rear direction by the hollow shaft, and the transmission of the working machine drive force is performed by the PTO system shaft passing through the hollow shaft. In the transmission structure of the tractor to be carried out, the following technical measures were taken.

That is, as illustrated in FIGS. 1, 4 and 5, the clutch housing 1 is integrally provided with a release shifter receiving cylinder 4 of the main clutch and mounted on the front surface of the supporting wall portion 5 on the inner surface of the clutch housing. The front bearing frame 6 and the rear bearing frame 7 mounted on the rear wall 1a of the clutch housing with a space D between the rear bearing frame 6 and the rear clutch frame 7 protruding rearward are installed, and the main clutch 3 A hollow input shaft 9 of the traveling system driven by means of is provided so as to project to the back side of the front bearing frame 6, and a hollow output shaft 10 of the traveling system located on the extension line of this hollow input shaft 9 is mounted on the rear bearing frame. 7 is provided between the two bearing frames 6 and 7 so as to project to the back side, and an intermediate shaft 11 parallel to the hollow output shaft 10 is provided between the bearing frames 6 and 7, and the hollow input shaft 9 is used. Hollow output shaft 10 driven in forward / reverse or high / low 2
Drive system transmissions 12A (Fig. 1), 12B (4th stage)
, 12C (FIG. 5) are arranged between the intermediate shaft 11 and the hollow output shaft 10, and the PTO drive shaft 13 is passed through the hollow input shaft 9 and the hollow output shaft 10 to form a rear bearing. The traveling system hollow input shaft 14 of the mesh case 2 and the PTO system input shaft 15 penetrating therethrough are provided so as to project to the rear side of the frame 7 with respect to the above-mentioned hollow output shaft 10 and drive shaft 13, respectively. The side bearing frame 7 and the clutch housing rear wall 1a are connected by the shaft couplings 16 and 17 within the space D.

In addition, the present invention, as illustrated in FIGS. 4 and 5, respectively, includes the traveling system transmissions 12B and 12C, two hydraulic clutches 18 and 19 for forward / reverse drive or high / low two-stage drive for the intermediate shaft. A hydraulic clutch type installed on top of the intermediate shaft 11, and an annular opening end 20a to the outer peripheral surface of the intermediate shaft 11 of the hydraulic oil passages 20 and 21 formed in the intermediate shaft 11 in communication with the hydraulic clutches 18 and 19 described above. An oil passage inheriting cylinder 22 that covers the rear bearing frame 7 is formed integrally with the rear bearing frame 7 so as to project from the rear surface of the rear bearing frame 7 into the space D.

[Action]

To assemble the clutch housing 1 from the opening on the inner peripheral side of the support wall 5 with the front bearing frame 6 removed.
Installed in the state shown in the figure, and then, the front bearing frame 6
The hollow input shaft 9 is externally inserted into the clutch housing 1 and then mounted on the front surface of the supporting wall portion 5. Next, the traveling system hollow input shaft 14 and the PTO system input shaft 15 of the mesh case 2 are inserted into the clutch housing 1 and the shaft couplings 16, 17 are inserted.
While mating with each other, the clutch housing 1 and the mesh case 2 are superposed in the front-rear direction, and then the spaces are connected.

〔Example〕

 FIG. 1-3 shows the main part of the tractor according to the first embodiment.

The front bearing frame 6 is a tubular portion 6a formed with holding portions for a pair of ball bearings 25 and 26 for supporting the hollow input shaft 9 on the outer peripheral surface side, and the release shifter receiving barrel 4 connected to the front thereof.
It is formed in a substantially flat plate shape except for, and is attached to the front surface of the support wall portion 5 by a connecting tool (not shown). The release shifter receiving cylinder 4 slidably receives a release shifter 27 carrying a release bearing 27a, and by depressing a clutch pedal (not shown), the release shifter 27 is displaced forward and the main clutch 3 is cut. Is customary. In the example shown in the figure, the PTO clutch 71 (3rd part) to be described later is placed in the PTO transmission path below the PTO system input shaft 15 of the transmission case 2.
Since the main clutch 3 functions only as a clutch for the traveling system, the drive shaft 13 of the PTO system is directly connected to the engine flywheel 28.

As shown in FIG. 2, the rear bearing frame 7 has five mounting legs.
A fixture 30 shown in FIG. 1 is formed in a fixture-like insertion hole 7b which is formed in a flat plate shape having 7a and extends to the end of each attachment leg 7a.
The rear bearing frame 7 is mounted by screwing it through and screwing it into the mounting hole 31 of the rear wall 1a of the clutch housing.

The hollow output shaft 10 is supported by a sleeve bearing 33 in the rear end bearing hole of the hollow input shaft 9 and a ball bearing 34 in the rear bearing frame 7. The intermediate shaft 11 is supported by the front and rear bearing frames 6 and 7 via ball bearings 35 and 36, respectively.

A gear 37 is integrally formed on the hollow input shaft 9 on the back side of the front bearing frame 6, and the gear 37 is meshed with a gear 38 fitted to the front end of the intermediate shaft 11. Gears on the rear end of the intermediate shaft 11
39 is fitted, the gear 39 is meshed with an idler gear 40 pivotally supported on the rear bearing frame 7, and the idler gear 40 is meshed with a gear 41 loosely fitted on the hollow output shaft 10. Hollow output shaft
The dual type synchronizer clutches 42F and 42R are provided by fitting the hub member 42a common to the 10 and the clutch 4
Gear 37 by the clutch engagement of 2F and clutch 42R
The clutch 42 engages the gear 42 with the hub member 42.
It is supposed to be connected to the hollow output shaft 10 via a. That is, the transmission 12A provided in the first embodiment is a mechanical type in which the hollow output shaft 10 is driven by the hollow input shaft 9 in the forward and reverse directions.

Ball bearing at the front end on the rear wall 1a of the clutch housing
The hollow input shaft 14, which is supported via 44, serves as a driving shaft of a main transmission 45 of a traveling system which is provided in the case 2 and is partially shown in FIG. A transmission shaft 47, the front end of which is supported by a wall 1a via a ball bearing 46, is rotated in multiple stages. The PTO input shaft 15 of the transmission case 2 has a PTO clutch 71 and a PTO transmission 73 shown in FIG. 3 for the PTO shaft 72 (FIG. 3) extending rearward from the tractor body. After that, it is transmitted. The shaft couplings 16 and 17 have a normal structure, the outer shaft coupling 16 is positioned between the rear bearing frame 7 and the clutch housing rear wall 1a, and the inner shaft coupling 17 is the hollow output shaft 10 and the hollow input shaft. Positioned between 14

FIG. 3 illustrates the transmission mechanism arranged inside the machine body from the front end of the case 2 to the rear end of the tractor machine in a scale smaller than that in FIG.

As shown in FIG. 3, a rear case 74 is connected to the mission case 2. A hollow intermediate shaft is provided on the extension of the hollow input shaft 14 in the latter half of the mesh case 2.
75 is loosely installed on the PTO system input shaft 15, and
A propeller shaft 76 is provided on an extension of the transmission shaft 47.
The propeller shaft 76 is projected into the rear case 74, and the rear end portion 76A formed separately is in mesh with the differential ring gear 77.
Have eight. The PTO system input shaft 15 also projects into the rear case 74, and the hydraulic clutch type PTO clutch 70 is disposed between the PTO system input shaft 15 and the intermediate shaft 79 on the extension line thereof. The PTO system transmission 73 is arranged between the drive shaft 80 connected to the intermediate shaft 79 and provided on the extension thereof and the hollow transmission shaft 81 loosely fitted on the PTO shaft 72.

The traveling system main transmission 45 includes four gears 83I, 83II, 83III, 83IV which are loosely fitted on the hollow input shaft 14 and four gears 84I, 84II, 84III, 84IV which are fixedly mounted on the gearshift shaft 47. Each bite,
A hollow input shaft 14 is provided with a synchronizer clutch for four-speed gear shifting.

Between the speed change shaft 47 and the propeller shaft 76, the hollow intermediate shaft described above is used.
The auxiliary transmission 85 of the traveling system is arranged by utilizing 75.
That is, the intermediate shaft 75 is deceleratingly connected to the speed change shaft 47 by gears 86 and 87, and two speed change gears 88II and 88III are fixedly installed. Of these, the reduction gear unit is used for the small diameter gear 88II.
A transmission gear 88I connected via 89 is arranged outside the intermediate shaft 75. On the propeller shaft 76, the first speed (creep speed) is obtained by meshing with the speed change gear 88I.
A shift gear 90 that engages with II to obtain the second speed is installed so that it can slide only. A gear 91 meshed with the speed change gear 88III is loosely fitted on the propeller shaft 76, and the shift metal piece 92 for selectively connecting the gear 91 and the speed change shaft 47 to the propeller shaft 76 allows the auxiliary transmission 85 to be connected. The third and fourth speeds are obtained.

A front wheel drive force extraction gear 93 is fixedly installed on the propeller shaft 76, and a gear 95 which is rotated from this gear 93 via an intermediate gear 94 is loosely fitted on the front wheel drive force extraction shaft 96 at the lower portion of the mesh case 2. However, a front wheel drive clutch 97 capable of coupling the gear 95 to the take-out shaft 96 is provided, and front wheel drive is also possible.

In the PTO system transmission 73, gears 98I, 98II are fixedly installed on the drive shaft 80, and gears 99I, 99II are loosely installed on the hollow transmission shaft 81, and either gear 99I, 99II is installed by the shift hardware 100. It is configured to be coupled to the speed change shaft 81 to obtain two speed changes.

On the PTO shaft 72, there is a ground PTO spaced apart from the speed change shaft 81.
Spline cylinder with gear 101 loosely fitted and fixed to PTO shaft 72
A clutch metal piece 103 is slidably mounted on the 102, and the clutch metal piece 103 connects the hollow speed change shaft 81 to the PTO shaft 72 for live PTO drive, and the gear 101 for the ground PT.
O drive can be selected as an alternative. Grand PTO
Gear 101 is gear 104,105, gland PT by propeller shaft 76
It is rotationally driven via the O transmission shaft 106 and the gear 107.

The PTO clutch 70 is a friction multi-plate type in which a plurality of friction elements are supported by a support metal 108 on the PTO system input shaft 15 and a clutch cylinder 109 on the intermediate shaft 79 so that they can slide only. ing. In FIG. 3, 110 is an internal gear pump for the PTO clutch 70 that uses the input shaft 15 as the pump shaft, and 111 and 112 are rear cases 74 for shaft support, respectively.
The front and rear supporting wall portions which are erected on the inner bottom surface of the are shown.

FIG. 4 shows the second embodiment.

In this embodiment, two front and rear gears 49 and 50 are loosely fitted and installed on the intermediate shaft 11 which is rotationally driven by the hollow input shaft 9 by transmission of the gears 37 and 38. Two gears, front and rear, on the hollow output shaft 10
An idler gear 5 in which 51 and 52 are fixedly installed, the gears 49 and 51 are directly meshed, and the gears 50 and 52 are pivotally supported by the rear bearing frame 7
Meshed through 3. Clutch case 5 on intermediate shaft 11
The above-mentioned two hydraulic clutches 18 and 19 in which 4 are integrated
However, it is installed between both gears 49 and 50. The hydraulic clutches 18, 19 each having a friction multi-plate type and having one and the other friction elements supported by the bosses of the gears 49, 50 and the clutch case 54 are operated by the respective gears 49, 50. , 50 to the intermediate shaft 11. As described above, the transmission 12B provided in this embodiment is constructed as a hydraulic clutch type in which the hollow output shaft 10 is driven in the forward and reverse directions by the hollow input shaft 9 by the selective operation of the hydraulic clutches 18 and 19. ing.

The hydraulic oil passages 20 and 21 formed in the intermediate shaft 11 are connected to the hydraulic chamber for pressing the friction element by the pistons 18a and 19a of the hydraulic clutches 18 and 19, respectively. The annular opening end 20a covered with the oil passage inheriting cylinder 22 integral with the rear bearing frame 7,
The reference numeral 21a functions as an oil passage rotary joint that connects the hydraulic oil passages 20 and 21 in the rotating intermediate shaft 11 to the external oil passage on the position fixed side.

In the second embodiment, the transmission 12B is of the hydraulic clutch type, and two hydraulic clutches 18 and 19 are provided.
The front-back width of 2B is larger than that of the transmission 12A provided in the first embodiment. Therefore, the front bearing frame 6 has a large-diameter cylindrical portion.
6b is provided to make the gap between the two bearing frames 6 and 7 larger than that in the first embodiment.

The other part of the second embodiment is the sleeve bearing 33.
First except that ball bearings 54 are used instead of
The same as in the embodiment.

FIG. 5 shows a third embodiment.

In this embodiment, a gear train for high speed by directly engaging gears 57, 58 is provided between the intermediate shaft 11 and the hollow output shaft 10 instead of the gear train for reverse rotation 50, 53, 52 in the second embodiment. Similar gears 4
The 9,51th train is used as a low speed gear train, and the transmission 12C is operated by selectively operating the hydraulic clutches 18,19.
Thus, the hollow output shaft 10 is configured as a hydraulic clutch type that drives in high and low stages.

In order to obtain the reverse drive of the vehicle, the traveling main transmission 45 in the transmission case 2 is provided with reverse shift gears 60, 59, 61 having an intermediate idler gear 59.

The structure of the other parts of the third embodiment is exactly the same as that of the second embodiment.

FIG. 6 shows a case where the clutch housing 1 of the same specifications used in the first, second and third embodiments is used in a tractor of a specification in which the transmission is not provided in the clutch housing.

In this structure, a hollow drive shaft 63 of a traveling system in which the hollow input shaft 4 and the hollow output shaft 10 are integrated is used, and the front bearing frame 6 has a hollow ball drive shaft 63 via a single ball bearing 64.
Is used to support the middle part of the. The rear bearing frame 7 is not used, but the mounting hole 31 of the clutch housing rear wall 1a is left as it is.

A ball bearing 65 is interposed between the hollow drive shaft 63 and the rear end of the PTO system drive shaft 13. In order to connect the hollow drive shaft 63 and the hollow input shaft 14, a sleeve 66 with a stopper projection 66a is fitted to the front end of the hollow input shaft 14, and the stopper projection 66a and a retaining ring 67 on the hollow drive shaft 63 are connected. A shaft coupling 68 positioned between is used. The traveling-system main transmission device 45 in the transmission case 2 is provided with reverse gear trains 60, 59, 61.

〔The invention's effect〕

According to the present invention, a front bearing frame 6 integrally forming a release shifter receiving cylinder 4 of a main clutch and a rear bearing frame 7 mounted on a rear wall 1a of the clutch housing with a space D are provided in the clutch housing 1 so as to face each other. , A traveling system hollow input shaft 9 protruding to the back side of the front bearing frame 6 and a hollow output shaft on an extension line thereof
Transmissions 12A, 12B, 12C that perform two-speed transmission between 10
Is configured by using the intermediate shaft 11 supported by both bearing frames 6 and 7 and is disposed between both bearing frames 6 and 7. To change the width, when the front-rear width is large, the front-side bearing frame 6 is provided with the large-diameter cylindrical portion 6b illustrated in FIGS. 4 and 5, respectively, and in FIGS. 4 and 5, respectively. A shaft coupling for a transmission that requires an auxiliary member such as the illustrated oil passage inheriting cylinder 22.
By using the space D between the rear bearing frame 7 and the clutch housing rear wall 1a, which is provided as the arrangement interval of 16,17, as the arrangement space of the auxiliary member, and in any of the transmissions of the specifications, the front and rear faces can be arranged opposite to each other. The front and rear bearing frames 6 and 7 stably support the shaft and allow the shaft and the speed change member to be freely arranged, so that the bearing housings 6 and 6 having the same specifications can be used. It will be possible to deal with it easily by changing the specifications of only 7. The clutch housing rear wall 1a does not have to have a special structure as long as it has a mounting portion for the rear bearing frame mounting leg 7a corresponding to the mounting hole 31 provided in the embodiment. Even in the case of a tractor in which the transmission is not provided in the housing, the supporting wall portion 5 on the inner surface of the clutch housing is used and only the flat bearing frame 6 integrally provided with the release shifter receiving cylinder 4 is used. The clutch housing 1 having the same specifications as those used can be used.

The clutch housing 1 can be easily installed from the front side of the clutch housing 1 as described in the section of the operation, and the hollow output shaft 10 on the side of the clutch housing 10 can be easily installed.
And a shaft coupling 16 for connecting the hollow input side 14 on the side of the case to the rear bearing frame 7 and the rear wall 1a of the clutch housing.
Between the hollow input shaft 14 and the PTO
The assembly work in which the system input shaft 15 is inserted into the clutch housing 1 and the required shaft connection is performed while the clutch housing 1 and the mesh case 2 are assembled can be easily performed.

According to the structure of claim 2, in the hydraulic clutch type, the oil passage inheriting cylinder 22 for forming the rotary joint portion of the hydraulic oil supply / discharge passage for the hydraulic clutches 18 and 19,
Since it is formed integrally with the rear bearing frame 7, the cost for manufacturing and assembling is greatly reduced, and since there is no mounting portion, the gap between the rear bearing plate 7 and the clutch housing rear wall 1a is reduced. It can be placed in D without difficulty.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing a main part of a tractor having the first embodiment, FIG. 2 is a schematic perspective view of a rear bearing frame provided in the first embodiment, and FIG. 3 is the tractor other part. FIG. 4 is a partially exploded longitudinal side view, FIG. 4 and FIG. 5 are longitudinal side views showing the essential parts of the tractor having the second embodiment and the third embodiment, respectively. FIG. 8 is a vertical cross-sectional side view showing a main part of a tractor having a clutch housing of the same specification as that of the tractor and not adopting the transmission structure of the present invention. 1 ... clutch housing, 1a ... clutch housing rear wall, 2 ... mission case, 3 ... main clutch, 4
...... Release shifter receiving cylinder, 5 …… Support wall, 6 …… Front bearing frame, 6b …… Large diameter cylindrical part, 7 …… Rear bearing frame, 7a …… Mounting leg, 7b …… Mounting tool insertion Hole, 9 ... Hollow input shaft, 10
...... Hollow output shaft, 11 ...... Intermediate shaft, 12A, 12B, 12C ...... Travel system transmission, 13 ...... Drive shaft, 14 ...... Traveling system hollow input shaft,
15 …… PTO system input shaft, 16 …… Shaft coupling, 17 …… Shaft coupling, 18,
19 …… hydraulic clutch, 20, 21 …… hydraulic oil passage, 20a, 21a…
… Annular open end, 22 …… Oil passage transfer cylinder, 30 …… Fixing device, 31
…… Mounting holes, 37,38,39 …… Gear, 40 …… Idler gear, 41 …… Gear, 42F, 42R …… Synchronizer clutch, 49,50 …… Gear, 51,52 …… Gear, 53 …… Idler gears, 57, 58 ... Gears.

Claims (2)

[Claims] 1. Between a clutch housing 1 and a mesh case 2 which are connected to each other in the front-rear direction, traveling power is transmitted through a hollow shaft, and working machine driving force is transmitted through the hollow shaft.
In the transmission structure of the tractor to be respectively driven by the PTO shafts, the clutch housing 1 is integrally provided with the release shifter receiving cylinder 4 of the main clutch, and the front bearing frame mounted on the front surface of the supporting wall portion 5 on the inner surface of the clutch housing. 6 and a rear bearing frame 7 mounted on the rear wall 1a of the clutch housing at a distance D from the rear wall 1a of the clutch housing by a mounting leg 7a projecting rearward, and driven by the main clutch 3. The hollow input shaft 9 of the traveling system is provided so as to project to the rear side of the front bearing frame 6, and the hollow output shaft 10 of the traveling system located on the extension line of the hollow input shaft 9 is provided on the rear side of the rear bearing frame 7. Protrudingly provided between the bearing frames 6 and 7, the hollow output shaft 10
The intermediate shaft 11 parallel to the above is provided between the both bearing frames 6 and 7,
Traveling system transmissions 12A, 12B, 12C that drive the hollow output shaft 10 in the forward / reverse direction or the high and low two stages by the hollow input shaft 9 are arranged between the intermediate shaft 11 and the hollow output shaft 10 and further drive the PTO system. The hollow input shaft 9 and the hollow output shaft 10 described above are provided with the shaft 13 so as to project toward the rear surface of the rear bearing frame 7, and the traveling system hollow input shaft 14 of the mesh case 2 and the PT penetrating the same.
The O-system input shaft 15 and the hollow output shaft 10 and the drive shaft 13 described above are respectively attached to the rear bearing frame 7 and the clutch housing rear wall.
A transmission structure characterized by being connected by shaft couplings 16 and 17 within the interval D between 1a. 2. The tractor transmission structure according to claim 1, wherein the traveling system transmissions 12B, 12C are provided with two hydraulic clutches 18, 19 for forward / reverse drive or high / low two-stage drive. A hydraulic clutch type installed on top of the intermediate shaft 11, and an annular opening end 20a to the outer peripheral surface of the intermediate shaft 11 of the hydraulic oil passages 20 and 21 formed in the intermediate shaft 11 in communication with the hydraulic clutches 18 and 19 described above. A transmission structure characterized in that an oil passage inheriting cylinder 22 that covers the bearings 21a is formed integrally with the rear bearing frame 7 so as to project from the rear surface of the rear bearing frame 7 into the space D.