JPS5817143Y2 - gear transmission - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a gear transmission, and in particular, in obtaining a four-speed transmission in a constantly meshing gear transmission, this can be achieved with a total of six gears. The purpose is to simplify the structure and enable a compact design.

In a vehicular gear transmission, when changing gears in four stages using a constant mesh type transmission, four irregularly shaped gears are placed on the gear shaft at intervals in the axial direction, and the four speed change gears are placed on the speed change shaft in relative rotation. Usually, two clutch bodies are provided between adjacent transmission gears, and the gears are engaged and disengaged to change the speed.

In view of the fact that a total of 8 gears and 2 clutch bodies were required to obtain a 4-speed transmission as described above, the present invention was designed to enable a 4-speed transmission even with a total of 6 gears. This has been improved to simplify the structure and enable compact assembly, and in particular, guarantees assembly in narrow spaces such as tractor transmissions. A gear shaft is mounted coaxially between the driving side transmission shaft and the gear shaft, and a touch body that slides in the axial direction is fitted between the driving side transmission shaft and the gear shaft, and between the gear shaft and the driven side transmission shaft, respectively. The gear shaft is provided with a fixed gear and an idling gear with a smaller diameter than the fixed gear on the driving side, and an idling gear with a larger diameter than the idling gear is provided on the driven side transmission shaft, and each idling gear is engaged with each clutch body. The present invention is characterized in that it is provided with a meshing portion that can be disengaged, and each of transmission gears of different diameters that are interlocked and meshed with each of the gears of different diameters are provided.

Hereinafter, a preferred embodiment of the present invention will be described in detail with regard to the case where it is employed in a tractor transmission, particularly in a PTO transmission section.

Of course, the present invention can be applied to the traveling speed change section of a tractor transmission, and can also be applied not only to tractors but also to various agricultural machinery and speed change sections in other industrial fields.

In FIG. 1, 1 is the first transmission case;
2 is a second case, and 3 is an intermediate case provided between the two cases, and these cases 1, 2, and 3 are connected to each other as the main body of the tractor body.

4 is the main clutch, which is connected to the primary clutch 5 and P as the driving system.
A secondary clutch 6 as a TO system is installed in parallel, and when a clutch operation body (not shown) is operated first, the primary clutch 5 is disengaged, and with subsequent operations, the primary clutch 5 and the secondary clutch 6 are disengaged.
both of which are configured to cut.

Reference numeral 7 denotes a propulsion system propulsion shaft, and numeral 8 denotes a PTO system propulsion shaft. Both wheels have a double shaft structure, and the engine power is interrupted by engaging and disengaging the main clutch 4.

Reference numeral 9 denotes a first transmission section of the traveling system, which includes a gear group 10 of different diameters on the propulsion shaft 7.
and each transmission gear group 12 on a transmission shaft 11 supported in parallel above the propulsion shaft 7. If the clutch bodies designated by reference numerals 13 and 14 are slid,
The figure shows a four-speed transmission.

The first transmission section 9 is built into the first case 1 and interlocks with the differential gear 16 via a second transmission section 15 built into the second case 2 and which has two high and low stages.

Note that 17 indicates a super speed reduction device.

Reference numeral 18 denotes a PTO transmission shaft, which is supported parallel to the lower part of the propulsion shaft 7. Between the PTO transmission shaft 18 and the propulsion shaft 8, a gear transmission 19 which is in a deceleration relation with respect to the transmission shaft 18 is installed independently. It is a provision.

20 is a PTO shaft as a driven side transmission shaft, and the second case 2
The transmission shafts 18, 20 are supported on the same axis.

Reference numeral 21 denotes a transmission section of the present invention, which is detachably housed between the front surface of the intermediate case 3 and the second case 2.

Referring to FIG. 2, reference numeral 22 denotes a transmission case, which is detachably attached to the front surface of the intermediate case 3. As shown in FIG.

23 is a gear shaft, which includes a driving side transmission shaft 18 and a driven side transmission shaft 20.
It is provided on the same axis between the two.

The shaft end of the transmission shaft 18 is fitted with an engaging cylinder 24 having an engaging part 24a, and the shaft end of the transmission shaft 20 is fitted with an engaging cylinder 25 having an engaging part 25a. has been done.

Engagement parts 26 a and 27 a are provided at both ends of the gear shaft 23 .
Each of the occlusal cylinders 26 and 27 is fitted with a mantle, and the axial movement of each occlusal cylinder is regulated by a retaining ring or the like, and the adjacent occlusal parts correspond to each other.

A clutch body 28 is fitted between the transmission shaft 18 and the gear shaft 23 and is movable in the axial direction to connect and disconnect the engaging portions 24a and 26a.

The two clutch bodies are separate clutch bodies, which are fitted onto the engaging cylinder 25 on the transmission shaft 20 so as to be movable in the axial direction to connect and disconnect the engaging parts 25a and 27a.

Reference numeral 30 denotes a speed change gear, which is fixed to the gear shaft 23 at approximately the center thereof in the longitudinal direction.

31 is a speed change gear, which is fitted on the gear shaft 23 from the drive side adjacent to the fixed speed change gear 30 so as to be relatively rotatable;
The boss portion 31 a is supported on the case 22 with a bearing 32 , and the other end of the gear shaft 23 is supported on the case 22 with a bearing 33 .

Note that the end portion of the boss portion 31a of this speed change gear 31 protrudes from the bearing 32 as an engaging portion 31b.

Further, this speed change gear 31 has a smaller diameter than the fixed speed change gear 30.

Reference numeral 34 denotes another speed change gear, which is fitted onto the driven side transmission shaft 20 so as to be relatively rotatable, is adjacent to the articulation cylinder body 25, and has an articulation part 34a in the corresponding part.

Note that this speed change gear 34 has a larger diameter than the fixed speed change gear 30.

Reference numeral 35 denotes a speed change subshaft, which is mounted on the speed change case 22 and the wall 37 of the second case 2 via three bearings 36, is substantially parallel to the gear shaft 23, and is an axial extension of the propulsion shaft 7. Located on the line.

38, 39, and 40 are transmission gears of different diameters, which are fitted and fixed on the transmission subshaft 37, and the largest gear 38 is the smallest gear 31 on the gear shaft.
The intermediate gear 39 is always in mesh with the intermediate gear 30 on the gear shaft, and the smallest gear 40 is always in mesh with the largest gear 32 on the gear shaft.

In the above configuration, when the engine power is connected to and disconnected from the propulsion shaft 8 through the engagement and disengagement of the secondary clutch 6 of the main clutch 4, it is transmitted to the drive side transmission shaft 18 through the gear transmission 19 at a reduced speed as shown in the figure.

Therefore, with the secondary clutch 6 disengaged, the clutch body 28 is first used to connect the engaging portions 24a and 26a from the neutral state shown in the figure, and the clutch body 29 is then changed from the neutral state shown in the figure.
When the occlusal parts 25 a and 27 a are connected, first, a required torque is transmitted to the transmission shaft 20 in a directly connected state.

Furthermore, if the clutch body 28 connects the engaging parts 24 a and 26 a, and the clutch body 29 connects the engaging parts 25 a and 34 a, the torque of the transmission shaft 18 changes from gear 30→39→40.
→ It is transmitted to the transmission shaft 20 through 34 at the required speed change.

In addition, the clutch body 28 connects the interlocking portion 24a and the interlocking portion 31b.
, and the clutch body 29 connects the engaging parts 27 a and 25 a.
If you connect the gears 31→38→3, the torque of the transmission shaft 18 will be
9 → 30, and is transmitted to the transmission shaft 20 at the required speed change.

In addition, the clutch body 28 connects the interlocking portion 24a and the interlocking portion 31b.
, and the clutch body 29 connects the engaging parts 34 a and 25 a.
By connecting the gear 31 → the torque of the transmission shaft 18 is
38 → 40 → 34, and is transmitted to the transmission shaft 20 at the required speed change.

Note that when the clutch bodies 28 and 29 are disengaged, the 2
The secondary clutch 6 is disengaged and the clutch bodies 28 and 29 are connected, respectively, before the secondary clutch 6 is engaged.

The present invention is as described above, and a total of three gears with different diameters are provided, two on the gear shaft and one on the driven side transmission shaft, and three gears with different diameters are also provided on the sub-shift shaft. Despite having a total of 6 gears with diameter gears and 2 clutch bodies, 4-speed shifting is possible, and compared to the previous model, a total of 2 gears are no longer required, resulting in a simpler structure. Of course, it is economically advantageous because it reduces the number of parts, and assembly and disassembly is convenient.

In addition, the length between the bearings can be reduced at least by the tooth width of one gear, which not only allows for a more compact design in the front-rear direction, but also has the advantage of reducing the load on the bearing due to the interlocking of each gear.

Furthermore, it is more cost-effective than a system in which three gears are provided on a gear shaft.

[Brief explanation of drawings]

The drawings show a specific example of the present invention; FIG. 1 is an overall cross-sectional view of a tractor transmission in which the present invention is applied to a PTO section, and FIG. 2 is a detailed cross-sectional view of the present invention. 18... Drive side transmission shaft, 20... Driven side transmission shaft, 22... Speed change case, 23...
・・Gear shaft, 24a, 25a, 26a, 27a・
...Each engagement part, 28.29...Each clutch body, 30...Fixed speed change gear, 31.34...
...Idle speed change gear, 37 ... Speed change subshaft, 3
8, 39. 40... Speed gear.

Claims (1)

[Scope of utility model registration request] A gear shaft is mounted coaxially between the driving side transmission shaft and the driven side transmission shaft, and slides in the axial direction between the driving side transmission shaft and the gear shaft, and between the gear shaft and the driven side transmission shaft, respectively. At the same time, a fixed gear and a idling gear with a smaller diameter than the fixed gear are provided on the gear shaft on the driving side, and an idling gear with a larger diameter than the idling gear is provided on the driven side transmission shaft. A gear transmission characterized in that the idle gear is provided with an engaging portion that is engaged and disengaged by each clutch body, and each of the transmission gears of different diameters is provided that interlocks and meshes with each of the gears of different diameter.