JPH0537081Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention includes a bearing for the rotating shaft and a portion aligned in the axial direction of the rotating shaft on a wall portion of the mission case that supports the rotating shaft. The present invention relates to a transmission case structure of a transmission device in which an oil passage is bored.

[Conventional technology]

In the above transmission device, conventionally, as shown in FIG. 8, the hole 35 for incorporating the bearing 34 was formed by casting during casting of the mission case, and the entire oil passage 33 was formed after casting of the mission case. Holes are formed in the wall portion 7d by drilling, and the assembling hole 35 and the oil passage 33 are partitioned by the wall portion 7d itself, which has the following disadvantages.

[Problem that the invention attempts to solve]

Not only does it take a lot of effort to drill holes for forming the oil passage, but it is also necessary to form the portion 39 of the wall portion 7d that separates the bearing assembly hole 35 and the oil passage 33 into a relatively thick wall so as to withstand hydraulic pressure. Therefore, it became necessary to make the entire wall portion 7d thick.

The purpose of the present invention is to reduce the labor required for forming oil passages and to make the case wall portion thinner.

[Means for solving problems]

The characteristic configuration of the present invention is that a wall portion of the transmission case supports a bearing for the rotating shaft, and a portion of an oil passage bored in the wall portion is formed in a state that is aligned with the bearing in the axial direction. A transmission case structure of a transmission device,
A portion of the oil passage is formed in a projected plane in the axial direction of the bearing as an oil passage portion that connects a plurality of oil passage portions within the wall portion, and is cast so that the portion and the installation hole of the bearing are in communication with each other. It is characterized in that it is formed by punching and that a partition member is fitted into the assembly hole to shut off the assembly hole and a part of the oil passage in a liquid-tight state.

[Effect]

The above characteristic configuration is based on the idea that the bearing support part and a part of the oil passage existing in the extension part of the support part in the direction of the rotational axis are formed all at once when the case is cast. Part of the drilling process can be omitted.

When casting is performed, a part of the oil passage and the bearing installation hole will be in communication, so something is needed to isolate them from each other, so a partition member is inserted into the installation hole, which is a machined surface. It fits.

By the way, since the partition member is a separate member from the case, it is easy to make the partition member from a material with superior strength to the case material, which tends to be relatively disadvantageous in terms of strength. It is possible to make the wall thickness of the partition portion thinner than in the case where the partition itself is partitioned, and to withstand a predetermined hydraulic pressure.

[Effect of idea]

As a result, it is no longer necessary to drill holes in a part of the oil passage, so the labor required for drilling the oil passage can be reduced compared to the conventional method, contributing to a reduction in the price of the transmission case.

Additionally, by reducing the thickness of the wall used to partition the oil passage and the bearing installation hole, it has become possible to make the transmission more compact and lighter.

〔Example〕

As shown in FIG. 7, a lift arm 3 connects various working devices, such as a rotary tiller, to the rear of a traveling machine body that is capable of driving front wheels 1 and rear wheels 2, respectively, and that can be operated up and down. An agricultural tractor is constructed by attaching a power take-off shaft 4 for transmitting power to a connecting work device.

The transmission devices for the front wheels 1, rear wheels 2, and power take-off shaft 4 are constructed as shown in FIG.

That is, the output of the engine 5 is transmitted to the input shaft 8 of the transmission case 7 via the clutch 6,
This rotational force of the input shaft 8 is transmitted to a gear transmission 9 for power extraction.
Then, the rotational force of the input shaft 8 is transferred to a traveling sub-transmission device 11 via a hydraulic continuously variable transmission device 10 for traveling.
The rotational output of this sub-transmission device 11 is transmitted to the rear wheel differential mechanism 13 through the first output shaft 12, and to the front wheel differential mechanism via the clutch gear 14, second output shaft 15, and rotary shaft 16. The signals are transmitted to the moving mechanisms 17, respectively.

The mission case 7 includes a first case body portion 7a, a second case body portion 7b, a third case body portion 7c, and the first case body portion 7a.
The inner space _S1 of the second case main body part 7b and the inner space _S2 of the second case main body part 7b are partitioned into wall parts 7d.

To configure the continuously variable transmission device 10 for traveling, as shown in FIGS. 2 and 3, the wall portion 7d connects the hydraulic pump 18 and the hydraulic motor 19.
A pair of main oil passages 20a, 20b drilled in
An accumulator 21 as shown in FIG.
At the same time, the connection oil passage 22a or 22b bored in the wall portion 7d is connected to the main oil passage 2.
0a or 20b, the hydraulic pump 18
a neutral valve 23 that short-circuits the pair of main oil passages 20a and 20b to ensure that the hydraulic motor 19 stops driving when the main oil passages 20a and 20b are operated to a neutral state;
are arranged and incorporated into the wall portion plan 7d so that the short-circuit connection is created by connecting the pair of connecting oil passages 22a and 22b.

As shown in FIG. 1, a trochoid type oil supply pump 24 is built into the wall portion 7d. This oil supply pump 24 is interlocked with an input gear 27 of an intermediate shaft 26 of the power take-off gear transmission 9 via a gear 25, and a third
As shown in the figure, it is connected to the second case main body portion 7b so as to suck oil through the suction oil passage 28, and
It is connected to the pair of main circuits 20a and 20b so as to supply oil via a hydraulic oil supply path 33 having a filter 30, a check valve 31, and a relief valve 32. In short, the oil supply pump 24 is driven by the rotational force of the power extraction gear transmission 9, and uses the lubricating oil contained in the second case main body part 7b and the third case main body part 7c as hydraulic oil for driving. It is arranged to supply the gear transmission device 10 with the fuel.

The suction oil passage 28 includes a first oil passage portion 28a bored in the wall portion 7d as shown in FIG.
This first oil passage portion 28a is composed of a second oil passage portion 28b that connects to the inside of the second case body portion 7b. Then, the hydraulic oil supply path 33
These include a first oil passage portion 33a bored in the wall portion 7d, a second oil passage portion 33b provided with the filter 30 outside the mission case 7, and the wall portion 7d. The third oil passage portion 33c, the fourth oil passage portion 33d, and the fifth oil passage portion are drilled in
Each of the oil passage portions 33e constitutes the oil passage portion 33e. The first oil passage portion 33a and the third oil passage portion 33
c and the fifth oil passage portion 33e are formed by drilling after the wall portion 7d is cast. As clearly shown in FIG. 4, the fourth oil passage portion 33d is
A bearing 34 for the intermediate shaft 26 as a rotating shaft supported by the wall portion 7d is arranged so as to be aligned in the axial direction of the intermediate shaft 26,
and a hole 35 for incorporating the bearing 34.
It is formed together with the assembly hole 35 by casting during casting of the wall portion 7d, and is prevented from coming off by a stopper ring 36, and by an O-ring 37. It is separated from the installation hole 35 by a partition member 38 that is fitted into the wall portion 7d in a sealed state.

[Another example]

The front wheel speed device that switches the front wheel drive speed between a state where the average peripheral speed of the left and right front wheels is the same as the average peripheral speed of the left and right rear wheels and a state where the average peripheral speed of the left and right rear wheels is greater than the average peripheral speed of the left and right rear wheels is a hydraulically operated clutch. Therefore, the transmission may be configured to perform a shifting operation, or the traction transmission may be configured to be configured to change gears by operating a hydraulically operated clutch, and an oil passage for operating the clutch may be provided. The present invention can also be applied to the case of drilling holes in the wall portion of the mission case. Therefore, the hydraulic oil supply path 33 is simply referred to as an oil path 33.

[Brief explanation of drawings]

The drawings show an embodiment of the transmission case structure of the transmission device according to the present invention, FIG. 1 is a partially cutaway side view of the transmission portion, and FIG. 2 is a partially cutaway front view of the transmission case wall portion. , Figure 3 is a hydraulic circuit diagram,
FIG. 4 is a partially cutaway side view of the wall portion of the transmission case, FIG. 5 is a sectional view of the accumulator, FIG. 6 is a transmission system diagram, and FIG. 7 is a side view of the entire agricultural tractor. FIG. 8 is a partially cutaway side view of a conventional wall portion. 7...Mission case, 7d...Wall part, 1
0... Hydraulic continuously variable transmission for traveling, 26... Rotating shaft, 33... Oil passage, 33c, 33e... Oil passage portion, 33d... Part, 34... Bearing, 3
5...Incorporation hole, 38...Partition member.

Claims (1)

[Claims for Utility Model Registration] 1. In the wall portion 7d of the transmission case 7,
A transmission case structure in which a bearing 34 for a rotating shaft 26 is supported, and a portion 33d of an oil passage 33 bored in the wall portion 7d is aligned with the bearing 34 in the axial direction. The portion 33d of the oil passage 33 is formed in a projected plane in the axial direction of the bearing 34 as an oil passage portion that connects the plurality of oil passage portions 33c and 33e within the wall portion 7d. , the part 33d and the assembly hole 35 of the bearing 34 are formed by casting in a communicating state, and the assembly hole 35 of the bearing 34 is formed by casting.
5. A transmission case structure in which a partition member 38 is fitted inside to shut off the installation hole 35 and the portion 33d of the oil passage 33 in a liquid-tight state. 2. The transmission case structure of the transmission device according to claim 1, wherein the oil passage 33 is a hydraulic oil supply passage for the hydraulic continuously variable transmission device 10.