JPH0311062Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention includes a double clutch configured to sequentially operate a travel system clutch and a PTO system clutch by a series of clutch disengagement operations, and An agricultural tractor configured to transmit the output of a traveling system transmission shaft and a PTO system transmission shaft extending in the form of a dual shaft inside and outside to a traveling system gear transmission section and a PTO system gear transmission section of a gear transmission case. Regarding transmission structure.

[Conventional technology]

This type of transmission structure is, for example,
As disclosed in Publication No. 42429, the engine and the cast gear transmission case are connected to form a vehicle body, and the double clutch and the double-internal/internal dual-shaft transmission shaft are housed inside the gear transmission case. It's decorated.

[Problem that the invention attempts to solve]

In the above conventional structure, the drive system transmission shaft and
To prevent the PTO system transmission shaft from being affected by distortion of the gear transmission case due to the weight of the machine,
The gear transmission case must be extremely strong, and only relatively large models in which the engine and gear transmission case are directly connected are equipped with a double clutch.

However, in recent years, there has been a demand for the introduction of double clutches in small and lightweight models that often use sheet metal housings in the car body. It is inevitable that the vehicle body will be distorted due to
Unless the transmission protection of the PTO system is ensured, it will be practically impossible to introduce a double clutch.

This invention was made in order to enable the introduction of a double clutch into a small agricultural tractor whose body structure includes a housing made of sheet metal.

[Means for solving problems]

Therefore, in the present invention, as shown in the embodiment, the double clutch 8 is housed in a clutch housing 2 directly connected to the engine 1, and the clutch housing 2 and the gear transmission case 4 are connected to a transmission housing 3 made of sheet metal. and a running system transmission shaft 9 in the form of a double shaft, an inner and outer shaft, which extends from the clutch housing 2 into the transmission housing 3.
A traveling shaft 13 that supports the PTO system transmission shaft 10 in a double shaft shape inside and outside the gear transmission case 4.
and PTO system input shaft 14 with flexible shaft joints 15 and 1, respectively.
6, and a shaft coupling 1 for the inner shaft.
5 is a ball joint, and the outer shaft joint 16 is a flange type elastic shaft joint surrounding the inner shaft joint 15.

[Effect]

According to the above configuration, even if the transmission housing 3 made of sheet metal is slightly distorted due to the vehicle weight or load and misalignment occurs between the inner and outer transmission shafts 9, 10 and the input shafts 13, 14, there is no interference in each transmission system. flexible shaft joints 15, 16
absorbs this.

[Effect of idea]

Therefore, according to the present invention, it has become possible to introduce a double clutch into a small agricultural tractor in which the sheet metal transmission housing 3 is incorporated into a part of the vehicle body.

In addition, the flexible shaft joints 15 and 16 installed in the transmission system with dual internal and external shafts utilize a ball joint on the inner shaft side and a flange-type elastic shaft joint on the outer shaft side that surrounds this. Since the flexible shaft joint structure is constructed, the entire joint can be assembled compactly, which is advantageous when incorporating it into a small machine.

〔Example〕

1 and 2 show a power transmission structure for an agricultural tractor according to the present invention.

An engine 1, a sheet metal clutch housing 2, a sheet metal transmission housing 3, and a cast gear transmission case 4 are connected in series to form a vehicle body, and this vehicle body has a structure that supports the loads of wheels attached to the front and rear. It's summery.

Inside the clutch housing 2, an engine flywheel 5, a traveling system clutch 6, and
A double clutch 8 in which PTO system clutches 7 are arranged in parallel at the front and rear is installed, and an internal power transmission shaft 9 whose power is connected and disconnected by the traveling system clutch 6 and the PTO system clutch 7 are arranged in parallel.
An external transmission shaft 10 whose power is switched on and off by a system clutch 7 is supported and projects rearward.

A release 12 is provided at the center of the rear end of the clutch housing 2 and is slid back and forth by an operating arm 11 linked to a clutch pedal (not shown). The system clutch 6 is disengaged, and a subsequent operation causes the PTO system clutch 7 to be disengaged.

A travel system input shaft 13 and a PTO system input shaft 14 are protruded from the front of the gear transmission case 4 in the form of an inner and outer double shaft, and are opposed to the inner and outer transmission shafts 9 and 10, so that the ends of each shaft can be aligned with each other. They are connected by flexible joints 15 and 16.

The shaft joint 15 of the traveling system is a ball joint in which an inner boss 15a and an outer boss 15b, which can be tilted at a small angle, are connected via a ball 15c.
The shaft coupling 16 of the system has a flange 16a on the transmission shaft 10 side.
An elastic shaft joint is employed in which the input shaft 14 and the flange 16b on the input shaft 14 side are connected by a ring-shaped leaf spring member 16c, and the elastic shaft joint 16 is arranged so as to surround the ball joint 15.

The gear transmission device incorporated into the gear transmission case 4 will be described below.

The driving gear transmission has 3 forward speeds and 1 reverse speed.
A main transmission mechanism 17 that changes gears, a super reduction mechanism 18 that changes gears between high and low gears, and a sub-transmission mechanism 19 are incorporated in series.

The main transmission mechanism 17 includes a first gear G ₁ fixed to the input shaft 13 , a second gear G ₂ , a third gear G ₃ , two-stage back gears G ₄ and G ₅ loosely fitted to the back shaft 20 , Consisting of a first shift gear G ₆ spline-fitted to two shafts 21, a second shift gear G ₇ , and an idling gear G ₈ constantly meshing with the third gear G ₃ , the first shift gear G ₆ is connected to the first gear G _1. occlusion and obtain 1st forward speed,
The first shift gear _G6 is engaged with the back gear _G4 to obtain reverse movement, and the second shift gear _G7 is engaged with the second gear _G2.
to obtain two forward speeds, and the second shift gear G ₇
By integrating this into the idling gear _G8 , three forward speeds can be obtained.

The super reduction mechanism 19 includes a first idling gear G ₉ and a second idling gear of a third shaft 22 integrally connected to the second shaft 21.
G ₁₀ , shift sleeve 23 externally fitted with a spline on the third shaft 22, gear G ₁₁ fixed to the fourth shaft 24,
_G12 , and when the shift sleeve 23 is spline connected to the first free rotating gear _G9 as shown in the figure,
The fourth shaft 24 is driven at a standard speed, and when the shift sleeve 23 is spline-connected to the second idling gear _G10 , the fourth shaft 24 is driven at a reduced speed. The sub-transmission mechanism 19 includes gears G ₁₃ and G ₁₄ fixed to the fourth shaft 24.
Consisting of two-stage shift gears G _{15 and} G ₁₆ spline-fitted to a bevel pinion shaft 25, which is the final gear shift shaft, when shift gear G ₁₅ is engaged with gear G ₁₃ , low speed is achieved, and shift gear G ₁₆ is engaged with gear G ₁₄ . High speed can be obtained by interlocking with. The bevel pinion shaft 25 is operatively connected to the rear axle mechanism via a bevel pinion gear _G17 .

Next, the PTO transmission system will be explained.

A pair of gears G ₁₈ and G ₁₉ are integrally formed in the insertion part of the PTO system input shaft 14 into the case, and two-stage shift gears G ₂₀ and G ₂₁ spline-fitted to the sixth shaft 26 below the input shaft 14 are connected to these gears. A PTO transmission mechanism 27 is configured that performs two-stage gear change, high and low, by selectively engaging G ₁₈ and G ₁₉ .

The power of the sixth shaft 26 of the PTO system is transmitted through gears G ₂₂ ,
The seventh shaft 28 and the eighth shaft directly connected thereto via G ₂₃
After being transmitted to the shaft 29, the torque is transmitted to the ninth shaft 31 via the torque limiter 30, and further to the reduction gear _G24 ,
G ₂₅ to the rear PTO shaft 32.

In addition, it is taken out via the gear G ₂₆ of the seventh shaft 28.
The PTO power is also transmitted to the intermediate PTO shaft 33 attached to the lower part of the case via gears G ₂₇ and G ₂₈ .

[Brief explanation of the drawing]

The drawings show an embodiment of the power transmission structure for an agricultural tractor according to the present invention, in which FIG. 1 is a longitudinal sectional side view of the first half of the transmission structure, and FIG. 2 is a longitudinal sectional side view of the second half. 2...Clutch housing, 3...Transmission housing, 4...Gear transmission case, 6
...Traveling clutch, 7...PTO clutch,
8...Double clutch, 9...Travel system transmission shaft, 1
0...PTO system transmission shaft, 13...Traveling system input shaft,
14...PTO system input shaft, 15...Flexible joint, 1
6...Flexible joint.

Claims (1)

[Scope of utility model registration request] A drive system power transmission shaft 9 is provided with a double clutch 8 configured to sequentially operate a drive system clutch 6 and a PTO system clutch 7 by a series of clutch disengagement operations, and extends from the double clutch 8 in the form of a dual inner and outer shaft. The output of the PTO system transmission shaft 10 is transferred to the traveling system gear transmission section of the gear transmission case 4 and the PTO system transmission shaft 10.
A clutch housing 2 in which the double clutch 8 is directly connected to the engine 1, which is a transmission structure for an agricultural tractor configured to transmit power to a system gear transmission section.
This clutch housing 2 and the gear transmission case 4 are connected by a transmission housing 3 made of sheet metal, and the clutch housing 2
A running system power transmission shaft 9 and a PTO system transmission shaft 10 are supported in the gear transmission case 4 in the form of double internal and external shafts, and a PTO system input shaft 13 is supported in the gear transmission case 4 in the form of a double internal and external shaft. It is connected to the system input shaft 14 via flexible shaft joints 15 and 16, respectively, and the shaft joint 15 for the inner shaft is a ball joint, and
A transmission structure for an agricultural tractor, in which an outer shaft coupling 16 is configured as a flange type elastic coupling surrounding the inner shaft coupling 15.