JPS6234051Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a dual shaft support structure for a tractor configured to transmit power from a double clutch to a transmission via a double shaft.

Conventional technology For example, in agricultural tractors, a dry double clutch is used for the main clutch in order to obtain drive system power and PTO system power from the engine. and PTO system power connection/disconnection, and power transmission from this double clutch to the traveling transmission mechanism and the PTO transmission mechanism is performed by dual shafts.

A clutch is connected to the engine-side end (front part) of each of the double shafts, a transmission gear is provided at the other end (rear part), and the dual shafts are supported by a partition wall inside the transmission case.

Problems to be Solved by the Invention In the above-mentioned conventional technology, the rear part of each shaft of the double shaft is supported via a bearing, but the midway part between it and the front part is not supported, and the transmission gear is not supported. The support provided at the rear part is not reliable, and it is also difficult to ensure the support strength of the part where the hub for connecting and disconnecting the clutch is provided. Additionally, oil may leak from the transmission case into the dry clutch housing.

Means for Solving the Problems The present invention provides an inner bearing 25 between the middle part of the center shaft 13 whose rear part is supported by the second partition wall 12 and the rear part of the outer cylinder shaft 10 which is supported by the first partition wall 2. An outer oil seal 26 is interposed between the middle part of the outer cylinder shaft 10 and the middle part of the cylindrical part 11a of the propulsion shaft case 11, which is fixed to the first partition wall 2 and has the hub 8 externally fitted in the front part. By interposing the bearing 21 and the outer oil seal 24, the problems of the prior art described above can be solved.

Function The center shaft 13, which is connected to the running clutch 5 at the front and supported by the second partition wall 12 at the rear, is supported at its midpoint by the rear of the outer cylindrical shaft 10 via the inner bearing 25 to prevent shaft vibration. Outer cylinder shaft 1 via the inner bearing 25
A transmission gear 16 provided at the rear of the transmission gear 16 is supported, and an outer cylindrical shaft 10 supported on the first bulkhead 2 by a main bearing 9 in front of the transmission gear 16 has a PTO clutch 6 at the front. The middle part is the first partition wall 2
The hub 8 is supported via an outer bearing 21 on the cylindrical portion 11a of the propulsion shaft case 11 fixed to the front surface of the cylindrical portion 11a of the propulsion shaft case 11. ing.

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

In FIGS. 1 and 2, reference numeral 1 denotes a front clutch case constructed as a part of the vehicle body of a tractor, and a transmission case 3 is integrally connected to the rear of the clutch case with a first partition 2 interposed therebetween. An engine (not shown) is connected to the front portion of these front and rear integral cases.

A travel clutch 5 and a PTO clutch 6 are connected to the flywheel 4 attached to the rear of the engine to form a dry double clutch, which is operated intermittently by the stepwise operation of the release fork 7 and the hub 8. Ru.

Reference numeral 9 denotes a main bearing fitted in the center of the first partition wall 2. The outer cylindrical shaft 10 fitted through this main bearing 9 has its front end connected to the PTO clutch 6, while its rear end is connected to the main bearing. It is designed to protrude slightly further back than 9. A propulsion shaft case 11 projecting forward from the first partition wall 2 is fitted in the radially outward direction of the outer cylinder shaft 10, and the hub 8 is attached to the front end of the cylinder portion 11a.
In order to support the outer cylinder shaft 10, an outer bearing 21 is interposed at the inner periphery of the middle part of the cylinder part 11a.

On the other hand, a center shaft 13 is inserted into and supported by the outer cylinder shaft 10 so that its rear end is supported by the second partition wall 12, and its front end is connected to the traveling clutch 5. Here center axis 1
3 is interposed with an inner bearing 25 for supporting the middle part of the outer cylinder shaft 10.

When the power is transmitted to the center shaft 13 in this way, the travel counter shaft 14 mounted on the rear and upper part of the center shaft 13
The transmission gear 15 of the continuous mesh traveling transmission system configured between
While variable speed transmission can be performed by
A PTO countershaft 20 is transmitted to change the speed by the PTO drive gear 18 and its driven gear 19 in a continuous mesh manner, and in combination with another PTO transmission disposed at the rear, a PTO transmission system is constructed.

In these clutch and transmission joint structures, the front part is usually a dry clutch case 1, and the rear part is, of course, a wet transmission case 3.

The outer bearing 21 is a needle type having a flat U-shaped outer ring 22, and has thrust rings 2 at the front and rear.
3 and 23, the cylindrical portion 11a of the propulsion shaft case 11
The outer oil seal 24 is tightly fitted to the front of the oil seal. On the other hand, the inner bearing 25 that supports the middle part of the center shaft 13 is also of the needle type, and is located corresponding to the inner circumference of the low-speed side PTO drive gear 16, and has a specially shaped inner oil seal near the front. 26 is provided with an outer peripheral metal ring 27 and a rubber O-ring spring 28, and in this case, between the inner bearing 25 and the inner oil seal 26,
An auxiliary collar 2 that overlaps the inner oil seal 26 from the outer periphery and limits deformation in the radial outward direction to a certain degree.
9 is fitted, which also functions as a spacer.

Note that no Oiles bearing is constructed in front of the inner oil seal 26, and on the other hand, the main bearing 9 mentioned above is constructed with two parts in order to achieve more complete shaft support.
It is organized into columns.

Therefore, in the above configuration, the outer bearing 21 receives oil from the transmission case 3 and is constantly lubricated and cooled, so its wear is low, and this reduces the axial runout of the entire double shaft. Since the play is suppressed to a small level and there is little play between the propulsion shaft cases 11, the outer oil seal 24 performs a stable and reliable sealing function in front of it, and this is the inner bearing 25.
The same applies to the inner oil seal 26, so it is possible to provide a very strong shaft support structure and sealing structure as a whole, and in particular, it is stably supported by the front outer bearing 21 and the main bearing 9. Outer cylinder shaft 10
Based on this, an inner bearing 25 is placed inside the PTO drive gear 16 at the rear end, which improves the stability and durability of its power transmission.

That is, in the dual shaft support structure of the present invention, the transmission case 3 having the second partition wall 12 is connected to the rear of the dry clutch case 1 via the first partition wall 2, and the center shaft 13 passing through the first partition wall 2 is connected to the transmission case 3 having the second partition wall 12. The rear part of the second bulkhead 1
2 and connects a traveling clutch 5 to the front part,
A traveling transmission transmission gear is provided in the rear part of the center shaft 13 from the first partition wall 2, and the PTO clutch 6 is connected to the front part of the outer cylindrical shaft 10 which passes through the first partition wall 2 and is fitted onto the center shaft 13. A PTO transmission system transmission gear is provided in the transmission gear, and a main bearing 9 for supporting the outer cylinder shaft 10 on the first partition wall 2 is arranged in front of this transmission gear, and the main bearing 9 that supports the outer cylinder shaft 10 on the first partition wall 2
The cylindrical portion 11 of the propulsion shaft case 11 fixed to the front surface of the
a into the middle part of the outer cylinder shaft 10, and
In the case where a hub 8 is slidably fitted on the front part of the main bearing 9 and the front part of the cylindrical part 11a, the outer cylindrical shaft 10 is connected to the front part of the cylindrical part 11a. A needle-type outer bearing 21 that rotatably supports the outer cylinder shaft 10 is provided between the outer peripheral surface and the inner peripheral surface of the cylindrical portion 11a, and the outer cylinder shaft 10 is connected to the main bearing 9 and the central portion of the shaft length. It is supported by an outer bearing 21 and is further provided with an outer oil seal 24 on the front side of the outer bearing 21 to prevent lubricating oil from the outer bearing 21 from flowing out into the clutch case 1. A needle type inner bearing 25 that fits between the surface and the outer peripheral surface of the inner shaft 13 and within the gear width of the PTO transmission transmission gear 16 at the rear of the outer cylinder shaft 10.
is provided to connect the middle portion of the shaft length of the center shaft 13 to the inner bearing 2.
5 and supported on the first partition wall 2 side via the main bearing 9,
Furthermore, an inner oil seal 26 is provided on the front side of the inner bearing 25 to prevent lubricating oil from the inner bearing 25 from flowing out into the clutch case 1.

Effects of the invention According to the invention described in detail above, the main bearing 9, the outer cylinder shaft 10 at the front part of the cylinder part 11a, and at the central part of the cylinder length.
A needle type outer bearing 21 rotatably supports the outer cylinder shaft 10 between the outer peripheral surface of the cylinder part 11a and the inner peripheral surface of the cylinder part 11a.
The outer cylinder shaft 10 is supported by the main bearing 9 and the outer bearing 21 at the rear part and the central part of the shaft length.
It is possible to securely support the shaft while suppressing the shaft runout, and to prevent mutual contact between the outer cylinder shaft 10, the cylinder portion 11a, and the center shaft 13.

Furthermore, an outer oil seal 24 is provided on the front side of the outer bearing 21 to prevent lubricating oil from the outer bearing 21 from flowing out into the clutch case 1.
Although the outer cylinder shaft 10 is stably supported and the outer bearing 21 is sufficiently lubricated to prevent seizure, etc., the lubricating oil is reliably prevented from leaking into the clutch case 1. Each of the clutches 5 and 6 in the clutch case 1 can be made of a dry type, making maintenance easier.

Further, a needle type inner bearing 25 is provided between the rear inner peripheral surface of the outer cylinder shaft 10 and the outer peripheral surface of the center shaft 13 and fits within the gear width of the PTO transmission transmission gear 16 at the rear of the outer cylinder shaft 10. Since the intermediate portion of the cylinder length is supported on the first partition wall 2 side via the inner bearing 25 and the main bearing 9, the center shaft 13, which is longer than the outer cylinder shaft 10 and is prone to shaft runout, can be stably and reliably supported. I can support it,
Together with the reliable support of the outer cylinder shaft 10, it is possible to reliably prevent the outer cylinder shaft 10 and the center shaft 13 of the dual inner and outer shaft structure from coming into contact with each other.

At this time, since the needle type inner bearing 25 is within the gear width of the PTO transmission transmission gear 16, the longitudinal length can be made very short to support the center shaft 13.

Furthermore, since an inner oil seal 26 is provided on the front side of the inner bearing 25 to prevent the lubricating oil from the inner bearing 25 from flowing out into the clutch case 1, the inner shaft 13 is surely supported by the inner bearing 25. And the inner bearing 2
5 is sufficiently lubricated to prevent seizure, etc., it is possible to reliably prevent the lubricating oil from flowing out and entering the clutch case 1 through the space between the inner shaft 13 and the outer cylinder shaft 10.

Therefore, the present invention prevents lubricating oil from flowing into the clutch case while ensuring stable support of the shaft and sufficient lubrication of the bearings for this support even in the case of a dual-shaft structure. It is very profitable.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is an enlarged sectional view of the main part. 1... Clutch case, 2... First bulkhead, 3...
...Mission case, 5...Traveling clutch, 6...
... PTO clutch, 9 ... Main bearing, 10 ... Outer cylinder shaft, 11 ... Propulsion shaft case, 12 ... Second bulkhead,
13...Center shaft, 16...Transmission gear (low speed side PTO
drive gear), 21...outer bearing, 24...outer oil seal, 25...inner bearing, 26...inner oil seal.

Claims (1)

[Claims for Utility Model Registration] A transmission case 3 having a second partition wall 12 is connected to the rear part of the dry clutch case 1 via the first partition wall 2, and the rear part of the center shaft 13 passing through the first partition wall 2 is attached to the rear part of the dry clutch case 1. A clutch 5 is supported on the bulkhead 12 and runs at the front.
A travel transmission transmission gear 15 is provided at the rear portion of the center shaft 13 from the first partition wall 2, and the first partition wall 2
The PTO clutch 6 is connected to the front part of the outer cylindrical shaft 10 which passes through the center shaft 13 and is fitted onto the inner shaft 13, and a PTO transmission transmission gear 16 is provided at the rear. Main bearing 9 supported by bulkhead 2
The cylindrical part 11a of the propulsion shaft case 11 fixed to the front surface of the first partition wall 2 is fitted onto the middle part of the outer cylindrical shaft 10, and the PTO clutches 5, 6 run on the front part of the cylindrical part 11a. In the case where a hub 8 is slidably fitted on the outside for connecting and disconnecting, the outer peripheral surface of the outer cylinder shaft 10 and the inner peripheral surface of the cylinder part 11a at the central part of the cylinder length between the main bearing 9 and the front part of the cylinder part 11a. In between, a needle type outer bearing 21 that rotatably supports the outer cylinder shaft 10 is provided, and the outer cylinder shaft 10 is supported at the rear part and the central part of the shaft length by the main bearing 9 and the outer bearing 21. An outer oil seal 24 is provided on the front side of the outer bearing 21 to prevent the lubricating oil from flowing into the clutch case 1, and between the rear inner circumferential surface of the outer cylindrical shaft 10 and the outer circumferential surface of the center shaft 13, A needle type inner bearing 25 that fits within the gear width of the PTO transmission transmission gear 16 at the rear of the outer cylinder shaft 10
is provided to connect the middle portion of the shaft length of the center shaft 13 to the inner bearing 2.
5 and supported on the first partition wall 2 side via the main bearing 9,
The dual shaft support structure for a tractor is further characterized in that an inner oil seal 26 is provided on the front side of the inner bearing 25 to prevent lubricating oil from the inner bearing 25 from flowing out into the clutch case 1.