JPH0444430Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention combines a double clutch connected to the output shaft from the engine and a gear type transmission equipped with a traveling system and a PTO system transmission mechanism. The present invention relates to a power transmission device for an agricultural tractor in which a shaped outer shaft and an inner shaft inserted therein are interlocked and connected.

[Conventional technology]

As the above-mentioned power transmission device, for example,
There is one disclosed in Publication No. 12142.

The inner shaft connected to the double clutch is a traveling system, and the outer shaft is a PTO system, and when the first stage of the double clutch is operated, the transmission to the inner shaft is cut off, and the second stage It is constructed so that the power transmission to the PTO system can be cut off by operation, and when changing the traveling gear while driving, the double clutch can be operated to the first gear to shift only the traveling system while driving the PTO system. It is now possible to perform gear shifting operations by cutting off the transmission.

In the above-described power transmission device, since the inner and outer shafts are long, a bearing bush is often interposed between the two shafts in order to maintain them concentrically. However, when a bushing is interposed between the inner and outer shafts in this way, when the power transmission from only the inner shaft is cut off to change the traveling speed, the rotational force of the outer shaft (PTO system), which continues to drive, is transferred to the inner shaft via the bushing. The rotational speed of the traveling system may not be sufficiently reduced due to so-called entrainment, which may make it difficult to smoothly perform a gear shift operation in the traveling system.

Therefore, in the above-mentioned conventional example, when a blade wheel that rotates in lubricating oil stored in the transmission case is incorporated into the gear type transmission of the traveling system, and the transmission of only the traveling system is cut off as described above, A means is employed to quickly reduce the rotation of the traveling system by using oil agitation resistance acting on the impeller.

[Problem that the invention attempts to solve]

However, if a method is adopted to reduce the rotation of the traveling system by applying rotational resistance to the traveling system as described above, the running performance of the agricultural tractor will only deteriorate due to the loss of power when the vehicle is running. However, there was a problem in that it led to economic disadvantages such as fuel efficiency.

The purpose of this invention is to prevent the above-mentioned rotation by creating a structure that does not cause power loss when the vehicle is running, and to enable smooth gear shifting operations in the running system. It is said that

[Means for solving problems]

The characteristic structure of the present invention, which has been made to achieve the above object, is that the front part of the outer shaft is fitted and supported in a boss part formed on the flywheel side member of the double clutch so as to be relatively rotatable. can be,
Its actions and effects are as follows.

[Effect]

In other words, by omitting the bushings that were interposed at the front of the outer shaft and inner shaft and supporting the outer shaft by fitting it into the flywheel side, the outer shaft and inner shaft This suppresses the power transmission that occurs between the shaft and the shaft, thereby preventing the occurrence of co-rotation. As a result, when the double clutch is operated to the first stage, the rotational speed of the shaft linked to the travel system is quickly reduced.

[Effect of idea]

As a result, it has become possible to reduce the rotational speed of the travel system and smoothly perform gear shifting operations in the travel system without employing means that would cause power loss.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.

As shown in FIG. 4, an engine E is disposed within the front hood 1 of the aircraft, a clutch housing 2 integrally connected to the rear end of the engine E, a fuel tank 3, a radiator 4, and a cooling fan 5 are supported by a frame 6. At the same time, a transmission case M is installed at the rear of the fuselage, which houses a gear-type transmission device F that receives power transmission from the output shaft of the clutch housing 2, and the drive unit 7 is installed in the middle of the fuselage. Power is transmitted to the lift arm 10 which can be supported by the lift arm 8 and 9 and can travel, and which can drive a working device such as a tilling device up and down at the rear end of the machine body, and the working device.
An agricultural tractor equipped with a PTO shaft 11 is configured.

A double clutch type power transmission device to which the present invention is applied is shown in FIG.

The clutch housing 2 is equipped with a double clutch 12 having a first clutch A for cutting off the power of the traveling system and a second clutch B for cutting off the power of the PTO system.
When the clutch pedal 13 is depressed to the first step, only the first clutch A of the travel system is disconnected, and when the clutch pedal is further depressed to the second step, the vehicle starts traveling. The first clutch A of the system and the second clutch B of the PTO system are disengaged.

Specifically, the first clutch A includes a flywheel 16 that rotates integrally with the output shaft 14 of the engine E, an inner shaft 15 whose one end is rotatably supported by the flywheel 16, and a spline on the inner shaft 15. The fitted first disk 18a and the first disk 18
The first part that clamps a in cooperation with the flywheel 16
The second clutch B is composed of a pressure plate 19a and the like, and the second clutch B is connected to the second flywheel 3 fixed to the flywheel 16.
9, an outer shaft 21 externally fitted onto the inner shaft 15, and a second disk 18 fitted with a spline to the outer shaft 21.
b, the second disk 18b is connected to the second flywheel 1
6b, and the like. And the first
At multiple locations in the circumferential direction of the pressure plate 19a, the first pressure plate 19a and following it, the second pressure plate 19 are moved backward toward the mission case M side, and the first disk 1
8a and the second disk 18b to disconnect the first clutch A and the clutch B, and a clutch release hub 23 for operating the release mechanism 22 is attached to the outside. The clutch release mechanism 22 is fitted onto the shaft 21 so as to be slidable in the axial direction, and the release mechanism 22 is configured to disengage the clutch when the clutch release hub 23 slides toward the engine E side.

The release hub 23 is adapted to slide in conjunction with the rocking of a clutch release fork 24 linked to the clutch pedal 13.

Next, the gear transmission F will be explained based on FIG. 2.

The inner shaft 15 is operatively connected to a first shaft 26 via a ball coupling 25, and three drive gears 41, 42, 43 are fitted to the first shaft 26.

Two shift gears 44 and 45 are spline-fitted to the second shaft 27, and the third drive gear 4
3, a first free rotation gear 48 that is always engaged with the first rotating gear 48 is externally fitted,
When the first shift gear 44 is shifted to the left in the figure, it engages with the first gear portion 51a of the back gear 51 shown in the lower part of the figure to move backward, and when it is shifted to the right, it engages with the first drive gear 41. By shifting the second shift gear 45 to the left, it engages with the second drive gear 42 to become the second forward speed, and by shifting to the right, the second shift gear 45 becomes the first forward speed.
It is configured to engage with the free rotation gear 48 to achieve three forward speeds. Note that the second gear of the back gear 51
The gear portion 51b is always engaged with the second drive gear 42.

A third shaft 28 is interlocked and connected to the second shaft 27, and second and third free rotating gears 49, 50 are connected to the third shaft 28.
By loosely fitting the sleeve 38 to the third shaft 28 and spline-fitting the sleeve 38 to the third shaft 28, and shifting the sleeve 38 to the left, the third shaft 28 and the second free rotating gear 4 are connected.
The first sub-transmission mechanism C is configured such that the gears 9 rotate together, and the third shaft 28 and the third idle gear 50 rotate together by shifting to the right.

Four intermediate gears 53, 54, 5 on the fourth shaft 29
5 and 56, of which the first intermediate gear 53
are always engaged with the second free rotation gear 49, and the fourth intermediate gear 56 is always engaged with the third free rotation gear 50, respectively.
Then, by shifting the third shift gear 46 spline-fitted to the output shaft 33 to the traveling system to the left, it becomes the second intermediate gear 54, and by shifting it to the right, it becomes the third intermediate gear 55. A second auxiliary transmission mechanism D that can be engaged with each other is constructed, and in synergy with the first auxiliary transmission mechanism C, a total of four stages of auxiliary transmission can be performed.

An outer shaft driving gear 59 is provided at the end of the outer shaft 21 on the mission case M side, and is always engaged with the first driven gear 58 fitted to the fifth shaft 30. Furthermore, a fourth shift gear 4 is attached to the fifth shaft 30.
7 is spline-fitted, and the fourth idler gear 6
0, and by shifting the fourth shift gear 47 to the left, it engages with the fifth intermediate gear 57 fitted to the sixth shaft 31, and by shifting it to the right, the sixth intermediate gear It is arranged to engage with the fourth free rotating gear 60 which is always engaged with the gear 58.
In other words, by selectively shifting the fourth shift gear 47 to the left or right, the sixth shaft 3
First, the power from the PTO system can be transmitted in two stages.

Two transmission shafts 34a are provided behind the sixth shaft 31,
34b, the front transmission shaft 34a is gear-linked with the mid-PTO shaft 35 protruding forward at the bottom of the transmission case M, and the rear transmission shaft 34b is connected to the transmission case M via the reduction mechanism G. The gear is interlocked with the PTO shaft 11 protruding from the rear end, and the power from the outer shaft 21 is transferred to the PTO shaft 11.
It is made so that it can be taken out.

In the above configuration, in the present invention, the following structure is added in order to quickly reduce the rotation of the inner shaft 15 of the traveling system when only the first clutch A of the traveling system is disengaged. .

That is, as shown in FIGS. 1 and 2, a boss portion 29a is provided in succession at the center of the second flywheel 39, which is a member on the flywheel side, and the outer shaft 21 is attached to the boss portion 39a. Push the front end 2
The rear part 21a of the outer shaft 21 is fitted and supported in a relatively rotatable manner via the transmission case M.
The front part of the first shaft 26 connected to the inner shaft 10 is fitted and supported by the rear part 21a of the outer shaft via a bush 20b. still,
The outer shaft 21 and its rear portion 21a are connected by a flexible coupling ring 40.

As a result, compared to the conventional structure in which the front part of the outer shaft 21 is externally supported by the inner shaft 15 via a bushing, the front part of the outer shaft 21 is attached to the second flywheel 39.
Since the outer shaft 21 is supported externally, the transmission of power due to friction from the outer shaft 21 to the inner shaft 15 is reduced, which is advantageous in terms of lowering the rotational speed of the inner shaft 15.

Note that although numbers are written in the claims section of the utility model registration for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of the drawing]

The drawings show an embodiment of the power transmission device for an agricultural tractor according to the present invention; FIG. 1 is a vertical side view of the double clutch portion, FIG. 2 is a vertical side view of the gear type transmission, and FIG. 3 is a side view of the agricultural tractor. It is an overall side view. 12...Double clutch, 14...Engine output shaft, 15...Inner shaft, 21...Outer shaft, 39...Flywheel side member, 39a...Boss portion, F...
...Gear type transmission.

Claims (1)

[Scope of utility model registration request] A double clutch 12 connected to an output shaft 14 from an engine E, and a gear type transmission F equipped with a traveling system and a PTO system transmission mechanism are connected to a cylindrical outer shaft 21 and an inner shaft 15 inserted therein. In this power transmission device for an agricultural tractor, the front part of the outer shaft 21 is fitted and supported in a boss part 39a formed on a member 39 on the flywheel side of the double clutch 12 so as to be relatively rotatable. A power transmission device for agricultural tractors.