JPS6034822Y2 - Rotation shaft mounting structure - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a structure for mounting a rotating shaft, and more particularly, to a structure for mounting a rotating shaft such as a shift support shaft in a tiller to a matching transmission case.

Conventionally, the gear shift support shaft 1' was aligned with the transmission case 2'.
As shown in FIG. 5, in order to attach the shaft 1' to the transmission case, a boss 3' is formed on one mission case piece 2'a, since accurate fitting with little play is required. A drill hole 5 is machined in the boss 3', and a support shaft 1' is inserted into the hole 5.
was fitted and inserted to rotatably support the transmission support 6.

For this reason, drilling is required, which increases costs, and even if grease is put into the drilling hole 5,
Since there is no grease reservoir, grease leaks out when the support shaft 1' rotates, and the support shaft 1' often fails to move smoothly.

Therefore, the purpose of the present invention is to provide a structure for mounting the rotating shaft that eliminates the above-mentioned drawbacks by installing the rotating shaft using the cast holes in each case piece that makes up the combined transmission case. It is something to do.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 4.

As shown in FIG. 1, the tiller 10 has a body 12 supported by wheels 11, and the body 12 has an engine 13, a mission 14, a belt transmission 15 connecting these, and the like. There is.

A gear shift lever 16 for operating the change gear of the transmission 14 extends toward the rear of the aircraft, and the lever 16 is rotatably supported by a gear shift support 6, and the gear shift support 6, as shown in FIG. The lever 16 is fixed to the transmission support shaft 1 which is rotatably supported by the transmission case 2, so that the lever 16 can be freely operated left and right and up and down.

In addition, the mission case 2 has left and right case pieces 2a and 2b.
These case pieces 2a are made of a combined case consisting of
, 2b is formed into a bottom shape by die-casting aluminum.

As shown in detail in FIGS. 3 and 4, these case pieces 2a and 2b have bosses 3 formed at their upper ends.
Drilling holes 18 and 19 are formed in the flange 17 and flange 17, respectively, and these casting holes 18 and 19 have drafting slopes A and B of about 3 degrees, respectively, and the respective holes 1
The small diameter tip of 8°19 is a gap regulating part 1 having a predetermined dimension.
They are 8a and 19a.

On the other hand, the transmission support shaft 1 has a transmission support 6 welded to one end thereof, and has a narrow diameter portion at the other end, and a stepped portion 1a is formed at a position that coincides with the mating surface C of the transmission case 2. ing.

When the mission case 2 is constructed by combining the left and right case pieces 2a and 2b, the center lines of both the flanged holes 18 and 19 are aligned, and the matched cast holes 1
8. After filling 19 with grease, insert the speed change support shaft 1.

Then, the large diameter part 1b of the support shaft 1 is fitted into the gap regulating part 18a of the casting hole 18 with a small tolerance, and the small diameter part 1c of the shaft 1 is fitted into the gap regulating part 19a of the casting hole 19 with a small tolerance. At the same time, the gaps a and b formed by the casting draft angles A and B become grease reservoirs.

Further, a C pin 21 is locked to the tip of the support shaft 1 protruding from the cast hole 19 via a washer 20, so that the flange 17 is held between the washer 20 and the shaft stepped portion 1a, and the flange 17 is held in the axial direction of the shaft 1. Sliding is prevented.

Since this embodiment has the above configuration, the engine 1
The rotation of No. 3 is transmitted to the mission 14 via the belt transmission device 15.
transmission to the transmission lever 16 in the transmission 14.
The gear is suitably changed by selective meshing of the change gear based on the operation, and the changed rotation is transmitted to the wheels 11 so that the tiller 10 runs.

At this time, when the gear shift lever 16 is operated up and down, the support shaft 1 rotates together with the gear shift support 6, but the gap regulating portions 18a, 19a of the cast hole 18, 19, which have precise predetermined dimensions,
supports the support shaft 1 rotatably at a predetermined distance apart from each other without wobbling, and is sufficiently lubricated by the grease reservoirs at and b based on the casting draft angles A and B, so that the support shaft 1 rotates smoothly. do.

Although the above-mentioned embodiment has been described with respect to the speed change support shaft 1, it is of course applicable to other rotating shafts such as the support shaft of a tension pulley arm.

As explained above, according to the present invention, the rotation shaft 1 is connected to each case piece 2a, 2b constituting the combined mission case 2.
Since it was installed using the cast holes 18 and 19 of the case 2, there is no need for drilling holes as in the conventional case, and a significant cost reduction can be achieved.
Since the small diameter tip portions 18a and 19a located on the outside are used as gap regulating portions, the rotating shaft 1 is supported with a predetermined tolerance at two positions separated by a predetermined distance, and wobbling such as miso movement is prevented. Since the gaps a and b with the rotating shaft 1 based on the casting draft angles A and H are used as grease reservoirs, the rotating shaft 1 is sufficiently lubricated and can rotate smoothly, and the grease reservoirs a,
The grease b is prevented from leaking to the outside by the gap regulating portions 18a and 19a, and smooth rotation of the rotating shaft 1 can be maintained for a long period of time.

Further, a stepped portion 1a is formed at the tip of the rotating shaft 1, and the stepped portion 1
a to the mating surface C of the mission case 2 and rotate the rotation axis 1.
When the axial movement of the rotating shaft 1 is prevented, the sliding surface 1a and the mating surface C are located in the grease reservoirs a and b, so that smooth rotation of the rotating shaft 1 can be maintained and wear can be prevented. Since the stepped portion 1a is not located outside the case 2, the appearance of the rotating shaft 1 can be neatly organized.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a tiller to which the present invention can be applied, Fig. 2 is a rear view of the transmission case portion of the tiller with the boss partially sectional, Fig. 3 is an enlarged sectional view of the part ■ in Fig. 2, Fig. 4 5 is an enlarged sectional view of the main part thereof, and FIG. 5 is a sectional view showing a conventional example. 1...Rotation axis (speed change support axis), 1a...
...Stepped section, 2...Mission case, 2a
, 2 b...Case piece, 18.19...
...Drilling hole, 18at 19a...Gap regulation part, A, B...Drilling slope, C...
Mating surfaces, a, b...Grease pool.

Claims (2)

[Scope of utility model registration request] (1) In a mission case made up of multiple case pieces shaped by casting, each case piece is shaped with a punched hole whose center line coincides with the other and has a predetermined draft draft angle. The rotating shaft is inserted into the casting hole, the small diameter tip located on the outside of the case of the casting hole is used as a gap regulating part, and the gap with the rotating shaft based on the casting draft angle is configured as a grease reservoir. Installation is structural. (2) The mounting of the rotating shaft according to claim 1 of the utility model registration claim is structured such that the rotating shaft has a stepped portion at its tip, and the stepped portion is in contact with the mating surface of the transmission case. .