JP2001059561A - Fluid machine incorporating rotary body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce rotational loss of a rotary body while surely lubricating slide parts in a fluid machine such as a hydraulic pump, a hydraulic motor, a hydrostatic transmission or the like. SOLUTION: In a hydrostatic transmission in which a hydraulic pump mechanism 2 is incorporated in the upper part of the inside of a closed container 11 while a hydraulic motor mechanism 3 is incorporated in the lower part thereof, a position where a drain port is formed is at a height which is substantially the same as that of an input shaft 26 of the hydraulic pump mechanism 2. The level of hydraulic oil in the closed container 11 is set to a vertically intermediate position of the hydraulic pump mechanism 2, thereby it is possible to reduce rotational loss of plungers 22 in the hydraulic pump mechanism 2 when they are rotated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fluid machine represented by a hydraulic pump, a hydraulic motor, an HST (hydrostatic transmission), and the like. In particular, the present invention relates to a measure for reducing rotation loss in a machine in which a rotating body rotates while being immersed in hydraulic oil.

[0002]

2. Description of the Related Art Conventionally, as a transmission mounted on a working vehicle such as a combine or a construction machine, for example, Japanese Patent Application Laid-Open No.
HST disclosed in Japanese Patent No. 129282 is used.

The HST has a configuration in which a hydraulic pump mechanism having an input shaft and a hydraulic motor mechanism having an output shaft are connected by an oil passage. Then, the driving force of the engine is transmitted from the input shaft to the hydraulic pump mechanism, and the hydraulic pressure generated by the hydraulic pump mechanism is supplied to the hydraulic motor mechanism via the oil passage. In the hydraulic motor mechanism, the output shaft rotates according to the supplied hydraulic pressure. Thus, the rotational driving force of the engine is changed and output from the output shaft of the hydraulic motor.

[0004] Specifically, the hydraulic pump mechanism has a plunger block in which a plurality of plungers are incorporated, and is integrally rotatably assembled with the input shaft. The plunger block is housed in a closed container formed by a housing and a center section. The inside of the closed container is filled with hydraulic oil, and the plunger block rotates while each sliding portion is lubricated by the hydraulic oil. By adjusting the inclination angle of the movable swash plate with which the tip of the plunger abuts, the plunger reciprocates to perform a pump action, and high-pressure oil is supplied to the hydraulic motor mechanism. The hydraulic motor mechanism has substantially the same configuration as that of the hydraulic pump mechanism. The hydraulic pressure acting on the plunger of the hydraulic motor mechanism is converted into the rotational force of the plunger block, and the output shaft rotates. Also in this hydraulic motor mechanism, the plunger block rotates in the working oil filled in the closed container formed by the housing and the center section.

[0005]

The inventors of the present invention are conducting various studies in order to improve the power transmission efficiency of the HST. Then, it has been found that reducing the rotation loss caused by the rotation of the plunger in the hydraulic oil greatly contributes to the improvement of the efficiency.

However, this hydraulic oil is indispensable for lubrication of each sliding portion, and the actual situation is that the hydraulic oil cannot be completely eliminated.

The inventors of the present invention have developed a configuration for effectively reducing the rotation loss caused by the rotation of the plunger in the working oil without hindering the lubrication of each sliding portion. Discussed further.

The present inventors have recognized that the means for reducing rotation loss proposed this time can be applied not only to the HST but also to other fluid machines such as a hydraulic pump and a hydraulic motor. are doing.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a hydraulic machine such as a hydraulic pump, a hydraulic motor, or an HST while reliably lubricating each sliding portion. Another object is to reduce the rotation loss of the rotating body.

[0010]

Means for Solving the Problems-Summary of the Invention-In order to achieve the above object, the present invention sets the oil level of hydraulic oil at a position lower than the upper end edge of the rotating body, Rotation loss during rotation can be reduced.

-Solution Means- Specifically, a first solution means taken by the present invention is based on a fluid machine in which a rotating body rotates in a container in which hydraulic oil is stored. In this fluid machine, the oil level of the working oil is set at a position lower than the upper end edge of the rotating body. According to this specific matter, when the rotating body rotates in the container, the rotation loss is reduced as compared with the case where the whole rotating body is immersed in the hydraulic oil.

Further, as a specific application form of this fluid machine, the following hydrostatic transmission is listed. That is, the second solution is the first solution, wherein the fluid machine is configured as a hydrostatic transmission including a hydraulic pump mechanism and a hydraulic motor mechanism in a container, and the hydraulic pump mechanism and the hydraulic motor mechanism are vertically arranged. It is arranged so that it is adjacent in the direction or diagonal direction. The rotating body is set as a plunger block in the upper mechanism of the two mechanisms, and the oil level of the hydraulic oil is set at a position lower than the upper end edge of the plunger block.

[0013] On the other hand, a third solution is the same as the first solution, wherein the fluid machine is configured as a hydrostatic transmission having a hydraulic pump mechanism and a hydraulic motor mechanism in a container in the same manner as described above. The mechanism and the hydraulic motor mechanism are disposed so as to be adjacent to each other in the horizontal direction. The rotating body is a plunger block provided in each of the two mechanisms, and the oil level of the hydraulic oil is set at a position lower than the upper end edge of the plunger block.

Further, the fourth solution is applied to a hydraulic device having a hydraulic pump mechanism or a hydraulic motor mechanism alone. That is, in the first solution,
It is configured as a hydraulic device having a hydraulic pump mechanism or a hydraulic motor mechanism alone in a container, and a rotating body is a plunger block provided in the hydraulic pump mechanism or the hydraulic motor mechanism. The hydraulic oil level is set at a position lower than the upper edge of the plunger block.

In particular, in the case of the horizontal hydrostatic transmission according to the third solution, it is possible to reduce the rotational loss of both plunger blocks of the hydraulic pump mechanism and the hydraulic motor mechanism.

The fifth solution embodies a configuration for setting the oil level of the hydraulic oil. That is, in the first, second, third, or fourth solution, the hydraulic oil discharge hole is formed at a position lower than the upper end edge of the rotating body on the container wall surface, and the hydraulic oil is discharged from the hydraulic oil discharge hole. Thereby, the oil level is set at a position lower than the upper edge of the rotating body. That is, the oil level of the hydraulic oil can be set only by appropriately setting the position of the hydraulic oil discharge hole.

According to a sixth aspect of the present invention, in the fifth aspect, the diameter of the hydraulic oil discharge hole is determined by the sum of the internal pressure of the container and the pressure head of the hydraulic oil in the container. It is set to be larger than the back pressure of the path. Thereby, the hydraulic oil in the container is smoothly discharged, and the oil level can be quickly set to an appropriate position.

According to a seventh aspect, in the fifth aspect, the formation position of the hydraulic oil discharge hole is set at a position facing the side surface of the rotating body on the container wall surface. Hydraulic oil is agitated around the rotating body, so that the hydraulic oil does not stay. By forming a hydraulic oil discharge hole facing this portion, the hydraulic oil can be smoothly discharged.

According to an eighth aspect of the present invention, in the fifth aspect of the present invention, an opening for opening the space in the container to the atmosphere is formed at a position near the axis of the rotating body in the container. This allows
It is possible to avoid a situation in which the inside of the container becomes negative pressure and the hydraulic oil cannot be discharged smoothly. That is, the hydraulic oil in the container can be easily discharged by natural fall.

A ninth solution is to make the oil level variable. That is, in a fluid machine in which a rotating body rotates in a container in which hydraulic oil is stored, an oil level adjusting mechanism for adjusting the oil level of the hydraulic oil is provided, and the oil level adjusting mechanism is
The oil level is switched according to the load acting on the rotating body.

In the tenth solution, a specific structure for making the oil level variable is specified. That is, a plurality of hydraulic oil discharge holes are formed in the container, and the hydraulic oil discharge holes are defined as a first hole formed at a relatively low position of the container and a second hole formed at a relatively high position of the container. Composed of When the load acting on the rotating body is less than a predetermined value, the hydraulic oil is discharged from the first hole. On the other hand, when the load exceeds the predetermined value, the hydraulic oil is discharged only from the second hole. Construct an oil level adjustment mechanism. According to this specific matter, it is possible to appropriately adjust the oil level according to a high load where lubrication performance is particularly required and a low load where lubrication performance is not so required compared to this high load. .

According to an eleventh solution, in the tenth solution, when the hydraulic oil is discharged from the first hole, an oil supply means for injecting the hydraulic oil toward the rotating body is provided. High lubrication performance can be obtained without increasing rotation loss of the rotating body by lubrication from the lubrication means.

According to a twelfth aspect, in the tenth or eleventh aspect, a cooling means capable of cooling hydraulic oil in the container is provided.

According to a thirteenth solution, the twelfth aspect is provided.
In the above solution, the cooling means performs the cooling operation of the hydraulic oil only when the hydraulic oil is discharged only from the second hole.

When the load is high, the temperature of the hydraulic oil tends to increase, and the lubricating performance may be deteriorated accordingly. According to this specific matter, high lubrication performance can be maintained by cooling the hydraulic oil during the high load.

According to a fourteenth aspect, in the thirteenth aspect, the fluid machine is configured as a hydrostatic transmission having a hydraulic pump mechanism and a hydraulic motor mechanism in a container, and the hydraulic pump mechanism and the hydraulic motor are provided. The mechanisms are arranged vertically or diagonally adjacent to each other. The cooling means is configured to cool only the upper part of the container. That is, the cooling effect of the cooling means is exerted only at a high load when the oil level rises. Therefore, an operation of performing a cooling operation at a high load and not performing a cooling operation at a low load can be performed only by specifying the arrangement position of the cooling unit,
There is no need to switch between starting and stopping the cooling operation of the cooling means.

According to a fifteenth solution, in the second solution, the oil level of the hydraulic oil is set at an intermediate position between the hydraulic pump mechanism and the hydraulic motor mechanism. Further, an oiling means for injecting hydraulic oil toward the upper mechanism of the hydraulic pump mechanism and the hydraulic motor mechanism is provided. For this reason, it is possible to ensure good lubrication performance of this mechanism without substantially causing rotation loss of the mechanism located on the upper side.

According to a sixteenth aspect, in the fifteenth aspect, the lubrication means is configured to perform lubrication when a load acting on the rotating body exceeds a predetermined value. This ensures good lubrication performance under high load.

According to a seventeenth solution, in the fifth solution, the hydraulic oil discharge hole is opposed to a flow of the hydraulic oil generated in a circumferential direction of the rotary body by the rotation of the rotary body in the hydraulic oil. And open it.

According to an eighteenth aspect, in the second aspect, the plunger block of the hydraulic pump mechanism and the plunger block of the hydraulic motor mechanism rotate in directions opposite to each other, so that the plunger block is located between the two plunger blocks. A hydraulic oil discharge hole is formed to face the flow of the generated hydraulic oil, and the hydraulic oil is discharged from the hydraulic oil discharge hole.

According to a nineteenth solution, in the second solution, the plunger block of the hydraulic pump mechanism and the plunger block of the hydraulic motor mechanism are rotatable in the same direction. In between, a guide plate for partitioning the arrangement spaces of these plunger blocks is provided. When the plunger block of the hydraulic pump mechanism and the plunger block of the hydraulic motor mechanism rotate in the same direction, the position opposing the flow of hydraulic oil generated in the circumferential direction of the plunger block due to the rotation of the plunger block of the hydraulic pump mechanism and the hydraulic pressure Hydraulic oil discharge holes are formed at positions opposing the flow of hydraulic oil generated in the circumferential direction of the plunger block by the rotation of the plunger block of the motor mechanism, and the hydraulic oil is discharged from the hydraulic oil discharge holes. I have.

According to a twentieth solution, in the seventeenth solution, a baffle plate is provided for directing the flow direction of hydraulic oil flowing along the outer peripheral surface of the rotating body toward the hydraulic oil discharge hole.

According to these specific items, it is possible to effectively use the flow of the hydraulic oil accompanying the rotation of the rotating body to improve the efficiency of discharging the hydraulic oil. In particular, according to the eighteenth solution, the flow directions of the hydraulic oil generated in opposite directions by the rotation of each plunger block can be partitioned by the guide plate and discharged from each hydraulic oil discharge hole, so that the effective discharge can be achieved. Operation becomes possible.

[0034]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, a case will be described in which the present invention is applied to an HST for a working vehicle such as a combine. Before describing the features of this embodiment, an outline of the HST 1 will be described.

FIG. 1 is a cross-sectional view showing the internal configuration of the HST 1, and FIG. 2 is a cross-sectional view taken along a line II-II in FIG. Also,
FIG. 3 is a diagram schematically showing an operation circuit of HST1.

As shown in FIGS. 1 and 2, HST1 is
The closed container 11 includes a housing 12 and a center section 13. The hydraulic pump mechanism 2 is housed in the upper half of the closed container 11, and the hydraulic motor mechanism 3 is housed in the lower half.

The hydraulic pump mechanism 2 includes a center section 1
3, a valve plate 21 in contact with the inner side surface, a plunger block 22 as a rotating body which is slidably and rotatably contacted with the valve plate 21, and an amount of oil discharged from the hydraulic pump mechanism 2 is adjusted. The movable swash plate 23 for performing the operation is provided.

As shown in FIG. 2, a plurality of hydraulic ports 21a and 21b are formed in the valve plate 21. On the other hand, in the center section 13, two oil passages 1 are provided.
3a and 13b are formed. Each hydraulic port 21
A part 21a of the a and 21b communicates with one oil passage 13a in the center section 13, and the other hydraulic port 21b communicates with the other oil passage 13b in the center section 13 (the oil passages 13a and 13b). Is shown by a virtual line in FIG. 2).

A plurality (for example, nine) of plunger holes 22a are formed in the plunger block 22 so as to surround the center axis of the plunger block 22, and a plunger 24 reciprocates in each of the plunger holes 22a. It is freely inserted.

The movable swash plate 23 is disposed so as to face the distal end of the plunger 24. The plungers 24 are brought into contact with the movable swash plate 23 via the thrust plate 25. I have.

The hydraulic pump mechanism 2 has an input shaft 26 extending in the horizontal direction and passing through the housing 12 and the center section 13. The input shaft 26 is provided at the center of the plunger block 22 and the movable swash plate 23.
The openings 22b and 23a through which are inserted are formed. The input shaft 26 is rotatably supported by the housing 12 and the center section 13 via bearings B and B, and is engaged with the plunger block 22 by spline fitting. That is, the plunger block 22 is rotationally and integrally engaged with the input shaft 26. One end (the right end in FIG. 1) of the input shaft 26 is configured to transmit a driving force of an engine (not shown). On the other hand, input shaft 2
6 is the center section 1 (the left end in FIG. 1).
3 and is connected to a charge pump 4 mounted on the outer surface of the center section 13. That is, the driving force of the engine input from the input shaft 26 is transmitted not only to the hydraulic pump mechanism 2 but also to the charge pump 4 so as to drive the charge pump 4.

The tilt angle of the movable swash plate 23 can be adjusted by a control arm (not shown) (FIG. 1 shows a state where the movable swash plate 23 is not tilted (tilt angle 0 °)). By adjusting the inclination angle, it is possible to adjust the amount of oil discharged from the hydraulic pump mechanism 2 and to switch between the high-pressure side and the low-pressure side of each of the hydraulic ports 21a and 21b. When the plunger block 22 rotates with the movable swash plate 23 inclined, the plunger 24 reciprocates in the plunger hole 22a, and high pressure is generated in some of the plunger holes 22a. The high-pressure oil is supplied to the hydraulic motor mechanism 3 from one oil passage 13 a formed in the center section 13 via a part of the hydraulic port 21 a of the valve plate 21.

Next, the hydraulic motor mechanism 3 will be described. The configuration of the hydraulic motor mechanism 3 is substantially the same as that of the hydraulic pump mechanism 2. That is, it includes a valve plate 31 in contact with the inner surface of the center section 13, a plunger block 32 as a rotating body which is slidably contacted with the valve plate 31, and a swash plate 33. The swash plate 33 of the hydraulic motor mechanism 3 is a fixed swash plate 33 having a fixed inclination angle. The configurations of the valve plate 31, the plunger block 32, and the plunger 34 are the same as those of the hydraulic pump mechanism 2, and the description is omitted here.

The hydraulic motor mechanism 3 has an output shaft 36. The output shaft 36 is rotatably supported by the housing 12 and the center section 13 via bearings B, B, and is plunged by spline fitting. It is engaged with the block 32. That is, the plunger block 32 is rotationally and integrally engaged with the output shaft 36.

With the above configuration, the hydraulic pump mechanism 2
, The plunger 34 of the hydraulic motor mechanism 3 to which the high-pressure oil is supplied presses the fixed swash plate 33, and the plunger 34 slides on the fixed swash plate 33 due to the reaction force. The output shaft 36 rotates.

Next, the operation circuit of the HST 1 will be described. As shown in FIG. 3, the suction side of the charge pump 4 is connected to an oil tank 14. This charge pump 4
A strainer 15 is provided at an upstream end of the suction line, and the oil purified by the strainer 15 is supplied to the charge pump 4. Charge pump 4
Is provided with an oil filter 16 on the discharge side. The oil purified by the oil filter 16 is branched into two systems.
Can be supplied to the oil passages 13a and 13b, and the other can be supplied to the inside of the closed container 11 via the low-pressure relief valve 18. The inside of the closed container 11 and the oil passages 13a and 13b of the center section 13 are communicated via a high-pressure relief valve 19. A collection pipe 5 forming a discharge path between the closed container 11 and the oil tank 14 is provided.
The recovery pipe 5 is connected to an oil cooler 51.
Is provided.

With the above configuration, the operation of the HST 1 is as follows. First, the hydraulic pump mechanism 2
Then, the input shaft 26 rotates, and the hydraulic pump mechanism 2 performs a predetermined pump operation. That is, the plunger block 22 rotates with the rotation of the input shaft 26, and the plunger 24 reciprocates in the plunger block 22 according to the inclination angle of the movable swash plate 23. As a result, high-pressure oil is discharged from a predetermined hydraulic port 21 a of the valve plate 21 toward one oil path 13 a of the center section 13. This high-pressure oil acts on some plungers 34 from one oil passage 13a through some hydraulic ports 31a of the valve plate 31 of the hydraulic motor mechanism 3. By the action of the hydraulic pressure, the plunger block 32 of the hydraulic motor mechanism 3 rotates, and accordingly, the output shaft 36 rotates. In the other hydraulic port 31b, the hydraulic motor mechanism 3 sends the hydraulic pump mechanism 2
The engine driving force is transmitted to the output shaft 36 while the oil circulates between the two mechanisms 2 and 3.

Further, if the inclination angle of the movable swash plate 23 is changed, the amount of oil discharged from the hydraulic pump mechanism 2 is changed, whereby the rotation speed of the output shaft 36 can be made variable. Also,
By changing the direction of inclination of the movable swash plate 23, it is possible to change one of the hydraulic ports 21a and 21b of the valve plate 21 from which high-pressure oil is discharged.
6 is switched between normal rotation and reverse rotation. Further, when the inclination angle of the movable swash plate is set to 0 ° (neutral position shown in FIG. 1), reciprocation of the plunger 24 is not performed, and no high pressure is generated from the hydraulic pump mechanism 2 and rotation of the output shaft 36 is stopped. I do. In other words, while the HST 1 is operating, the output shaft 3
6 can be put into a stopped state.

In such an operation, if oil leaks in the circuit, oil is supplied from the charge pump 4 into the circuit to compensate for the loss. In this supply operation, the oil pumped from the oil tank 14 to the charge pump 4 is purified by the oil filter 16 and then supplied into the circuit from the check valve 17.

Oil (hydraulic oil) circulates between the sealed container 11 and the oil tank 14. That is, part of the oil taken out of the oil tank 14 and passed through the charge pump 4 and the oil filter 16 is supplied to the low-pressure relief valve 1.
After that, it is supplied to the closed container 11. On the other hand, the hydraulic oil in the closed container 11 is taken out from the recovery pipe 5, cooled by the oil cooler 51, and then recovered in the oil tank 14.

With the above operation, the rotational driving force of the engine is continuously changed by the HST 1 and output to the output shaft 36.

Description of Oil Level Setting Structure Next, a structure for setting the oil level position in the sealed container 11 which is a feature of the present embodiment applied to the HST 1 configured as described above. explain. There are various forms of the oil level setting structure. Hereinafter, each embodiment will be described individually.

First, in the following first and second embodiments, the oil level is set by appropriately setting the connection position of the collection pipe 5 to the closed container 11.

<First Embodiment> In the oil level setting structure according to the present embodiment, the connection position of the recovery pipe 5 to the closed vessel 11 is set at substantially the same height as the input shaft 26. That is,
As shown in FIG. 4, a drain port 6 as a hydraulic oil discharge hole is formed on a side surface of the housing 12, and the recovery pipe 5 is connected to the drain port 6. Specifically, the lower end position of the drain port 6 is set so as to match the axial center position of the input shaft 26 (the center vertical position of the hydraulic pump mechanism 2).

According to this configuration, a part of the hydraulic oil in the sealed container 11 (the hydraulic oil at a position higher than the drain port 6) is discharged from the drain port 6. Therefore, the oil level in the sealed container 11 is set near the lower end position of the drain port 6, that is, near the axial center position of the input shaft 26. In other words, while the hydraulic motor mechanism 3 is entirely immersed in the hydraulic oil, the hydraulic pump mechanism 2
Is in a state where only the lower half thereof is immersed in the hydraulic oil. 4 and 5, the position of the oil surface is indicated by O.

Therefore, the rotation loss when the plunger block 22 of the hydraulic pump mechanism 2 rotates is reduced as compared with the case where the entire hydraulic pump mechanism 2 is immersed in the hydraulic oil. Also, since the lower half of the hydraulic pump mechanism 2 is immersed in the hydraulic oil, the plunger block 2
When 2 rotates once, substantially the entire plunger block 22 is temporarily immersed in the working oil. For this reason,
Lubrication of each sliding portion is well ensured.

As described above, according to the present embodiment, it is possible to improve the power transmission efficiency of the HST 1 by reducing the rotation loss when the plunger block 22 rotates, while maintaining the lubrication performance of the entire HST 1 in good condition. .

The height position of the drain port 6 is not limited to the above. For example, when it is desired to ensure the lubrication performance of the entire HST 1 higher, the formation position of the drain port 6 is set higher than the above position. Conversely, if the lubrication is not hindered even if the oil level position is lowered below the above-mentioned position, the formation position of the drain port 6 is set to a lower position. That is, if the height position of the oil surface O is set to a position lower than the upper end position of the plunger block 22, the above-described effect (the effect of reducing the rotation loss) can be obtained, so that the lubricity is not affected. By setting the oil level O as low as possible within the range, an optimum oil level position can be obtained.

(Explanation of Opening Diameter of Drain Port 6)
The opening diameter of the drain port 6 will be described. If the opening diameter of the drain port 6 is too small, the discharge amount of the hydraulic oil from the closed container 11 to the oil tank 14 is sufficiently obtained with respect to the supply amount of the hydraulic oil from the charge pump 4 to the closed container 11. I can't. For this reason, the oil level may not be set at the above position. In order to avoid such a situation, the lower limit of the opening diameter of the drain port 6 is set as follows.

That is, the opening diameter of the drain port 6 is set so that the following equation (1) holds.

(Internal pressure of closed container) + (head difference)> (back pressure of recovery pipe) (1) Here, “head difference” means the oil level of hydraulic oil in closed container 11 to oil tank 14 The pressure head according to the height dimension up to the oil level.

Specifically, the minimum opening diameter required for the drain port 6 is determined by the supply amount of the working oil from the charge pump 4 to the closed container 11. FIG. 6 is a diagram showing the relationship between the two. That is, the diagram shown in FIG. 6 shows the lower limit of the opening diameter required for the drain port 6.

Although the upper limit of the opening diameter of the drain port 6 is not particularly defined, the shape of the housing 12 and the closed container 1 are not limited.
1 is set in consideration of the required rigidity and the like.

(Description of Opening Position of Drain Port 6) The formation position of the drain port 6 in the height direction on the side surface of the housing 12 is as described above. Here, the formation position of the horizontal drain port 6 on the side surface of the housing 12 will be described.

The position where the drain port 6 is formed is preferably a position facing the plunger block 22 of the hydraulic pump mechanism 2. That is, it is preferable to form the drain port 6 in the region A in FIG. This is because the hydraulic oil is stirred around the plunger block 22 by its rotation, and there is no stagnation of the hydraulic oil in this portion.
This is because the discharge of the hydraulic oil from the drain port 6 can be performed relatively smoothly.

(Description of formation position of air holes) Further, FIG.
It is preferable that an air hole 11a is formed in the upper part of the closed container 11 as shown in FIG. This is because by setting the internal pressure of the sealed container 11 to the atmospheric pressure, the hydraulic oil can be smoothly discharged from the drain port 6 by natural fall. That is, when the internal pressure of the closed container 11 is in a negative pressure state, there is a possibility that the hydraulic oil from the closed container 11 cannot be discharged smoothly. For this reason, the inside of the sealed container 11 is opened to the atmosphere, and the oil level in the sealed container 11 and the oil tank 14 are reduced.
Hydraulic oil can be discharged smoothly due to the head difference from the inner oil level.

Specifically, an air inlet pipe 11b is connected to the air hole 11a, and one end of the air inlet pipe 11b communicates with an upper layer (air layer portion) in the oil tank 14. In particular, it is preferable that the position where the air hole 11a is formed also be a position facing the plunger block 22 of the hydraulic pump mechanism 2 (in the area A in FIG. 5). This is because the air is relatively smoothly introduced around the plunger block 22 by stirring the air due to the rotation of the plunger block 22.

It should be noted that the above-described “opening diameter of the drain port 6”, “opening position of the drain port 6”, and “formation position of the air hole” are only applicable to the HST 1 according to the first embodiment. However, the present invention can be similarly applied to the following embodiments.

In this embodiment, the hydraulic pump mechanism 2 and the hydraulic motor mechanism 3 have been described as being arranged side by side in the vertical direction, but they may also be arranged in an oblique direction. Applicable.

<Second Embodiment> This embodiment relates to a horizontal HST1.
In this case, the present invention is applied. As shown in FIG. 7, in the HST 1 according to the present embodiment, a hydraulic pump mechanism 2 and a hydraulic motor mechanism 3 are arranged in a horizontal direction. That is, the input shaft 26 and the output shaft 36 are set at the same height position. Other configurations are substantially the same as the above-described HST1.

In the HST 1, the oil level setting structure of the present embodiment is set so that the lower end position of the drain port 6 coincides with the axial center positions of the input shaft 26 and the output shaft 36.

According to this configuration, both the hydraulic motor mechanism 3 and the hydraulic pump mechanism 2 are in a state where only the lower half thereof is immersed in the working oil (see oil level O in FIG. 7).

Therefore, in the case of this embodiment, the plunger blocks 22, 32 of the mechanisms 2, 3 rotate compared to the case where the entire hydraulic pump mechanism 2 and the hydraulic motor mechanism 3 are immersed in the hydraulic oil. In this case, the rotation loss at the same time is reduced. In addition, since the lower half of each of the mechanisms 2 and 3 is immersed in the hydraulic oil, lubrication of each sliding portion is ensured well. Therefore, also in the present embodiment, H is reduced due to a reduction in rotation loss when the plunger blocks 22 and 32 rotate.
The efficiency of ST1 can be improved, and the HST
1. Good lubrication performance of the whole can be ensured.

Also, in the present embodiment, the formation position of the drain port 6 is not limited to the above. In other words, the oil level O is set as low as possible without impairing the lubricity.
Is set, the optimum oil level position can be obtained.

<Third Embodiment> In a third embodiment, the oil level can be adjusted according to the load of the HST 1.

As shown in FIG. 8, drain ports 61 and 62 are formed on the side and top surfaces of the housing 12, respectively. Drain port (first hole) 6 on the side surface of housing 12
The formation position of 1 is the same position as in the case of the first embodiment. Drain port (second hole) 6 on the upper surface of housing 12
The formation position of 2 is the same position as the drain port provided in the conventional general HST. And H
When the load is high in ST1, the hydraulic oil is discharged only from the drain port 62 on the upper surface of the housing 12, and when the load is low, the hydraulic oil is discharged only from the drain port 61 on the side surface of the housing 12.

More specifically, as shown in FIG. 8, first and second recovery pipes 5 are provided in a drain port 61 on the side of the housing 12 and a drain port 62 on the upper surface of the housing 12, respectively.
2 and 53 are connected. The first recovery pipe 52 connected to the drain port 61 on the side of the housing 12 has a first on-off valve 54.
However, a second on-off valve 55 is provided in each of the second recovery pipes 53 connected to the drain port 62 on the upper surface of the housing 12. The recovery pipe 5 downstream of these on-off valves 54 and 55
2 and 53 are connected to each other and connected to the oil tank 14. Each of the on-off valves 54 and 55 may be directly operated manually, or may be one that is opened and closed by transmitting an operation force to an operation unit (not shown) through a transmission unit such as a wire. This constitutes an oil level adjusting mechanism.

With the above configuration, when the load is high, the first on-off valve 54 is closed and the second on-off valve 55 is opened. Thereby, the hydraulic oil can be discharged only from the drain port 62 on the upper surface of the housing 12. That is, the operation of discharging the hydraulic oil is not performed until the oil level O reaches the upper end in the closed container 11. Therefore, the inside of the sealed container 11 is always filled with the working oil, and the respective mechanisms 2 and 3 are driven in a state where not only the hydraulic motor mechanism 3 but also the entire hydraulic pump mechanism 2 is immersed in the working oil. For this reason, at the time of a high load that requires high lubrication performance, the mechanisms 2 and 3 are well lubricated.

When the load is low, the second on-off valve 55 is closed and the first on-off valve 54 is opened. Thereby, the hydraulic oil can be discharged only from the drain port 61 on the side surface of the housing 12. That is, the mechanisms 2 and 3 are driven while the oil level O is set near the height of the axis of the input shaft 26 of the hydraulic pump mechanism 2 (see the dashed line in FIG. 8). For this reason, as in the case of the first embodiment described above, the rotation loss when the plunger block 22 of the hydraulic pump mechanism 2 rotates is reduced. Also, when the load is low, higher lubrication performance is not required than when the load is high. For this reason, even in a state where only the lower half of the hydraulic pump mechanism 2 is immersed in the hydraulic oil, the lubrication performance of each sliding portion is sufficiently ensured.

As described above, according to this embodiment, the oil level is adjusted in accordance with the load state of the HST 1, that is, the required lubrication performance, so that high lubrication performance is ensured at high load and sufficient lubrication performance is maintained at low load. HST is achieved by reducing the rotation loss when the plunger block 22 rotates, while ensuring excellent lubrication performance.
1 can be improved in efficiency.

The three-way valve 56 (FIG. 9) and the solenoid valves 57 and 58 (FIG. 1) are used in place of switching the drain ports 61 and 62 for discharging the hydraulic oil by the on-off valves 54 and 55.
0) can also be used. That is, as shown in FIG. 9, a three-way valve 56 is provided at a connection portion between the first recovery pipe 52 and the second recovery pipe 53, and the oil level can be adjusted by switching the three-way valve 56. As shown in FIG. 7, electromagnetic valves 57 and 58 may be provided in place of the on-off valves 54 and 55, and the oil level may be automatically adjusted by switching these electromagnetic valves 57 and 58 alternately.

In order to automatically adjust the oil level using the solenoid valves 57 and 58, it is necessary to open and close the solenoid valves 57 and 58 while detecting the load of the HST1. As an example of this load detection operation, as shown in FIG. 10, an oil temperature sensor S is provided in a closed container 11, and when the oil temperature detected by the oil temperature sensor S is equal to or higher than a predetermined temperature, a high load is detected. When the temperature is equal to or lower than the predetermined temperature, it is determined that the load is low, and the switching operation of each of the solenoid valves 57 and 58 is performed based on this determination.

Further, as in the present embodiment, two drain ports 61 and 62 are provided, and the oil level position is adjusted by switching the drain ports 61 and 62 for discharging the hydraulic oil. The present invention is also applicable to the horizontal HST 1 shown in the embodiment.

In the following fourth to sixth embodiments, the auxiliary drain port is provided in the sealed container 11 in the first embodiment, and the position of the auxiliary drain port is optimized to discharge the hydraulic oil. This is to improve efficiency.

<Fourth Embodiment> The HST 1 of the present embodiment is the same as that shown in FIG.
As shown in FIG. 1, an auxiliary drain port 63 is provided below the drain port 6 (hereinafter, referred to as a main drain port) on the side surface of the sealed container 11. The auxiliary drain port 63 is connected to the plunger block 22 of the hydraulic pump mechanism 2.
The hydraulic motor mechanism 3 is formed so as to face a substantially intermediate position between the plunger block 32 and the plunger block 32 (FIG. 11 shows only the outer shapes of the plunger blocks 22 and 32).

In the HST 1 of this embodiment, when the output shaft 36 rotates forward, the plunger block 22 of the hydraulic pump mechanism 2
Rotates counterclockwise in FIG. 11, and the plunger block 32 of the hydraulic motor mechanism 3 rotates clockwise in FIG. 11 (see the arrow indicated by the solid line in FIG. 11). For this reason, these plunger blocks 22, 32
11, a flow of hydraulic oil (a flow in the circumferential direction of both plunger blocks 22 and 32) as shown by a broken line arrow in FIG. 11 is generated. The auxiliary drain port 63 is located on the downstream side of the flow of the hydraulic oil (a position facing the flow), whereby the hydraulic oil in the closed casing 11 is forcibly discharged from the auxiliary drain port 63. It has become so. That is, the hydraulic oil is discharged by the dynamic pressure acting from both plunger blocks 22 and 32. An auxiliary recovery pipe 59 is connected to the auxiliary drain port 63, and a downstream end of the auxiliary recovery pipe 59 is connected to the recovery pipe 5 connected to the main drain port 6.

According to the configuration of the present embodiment, the auxiliary drain port 63 is provided in addition to the main drain port 6, and the hydraulic oil is forcibly discharged from the auxiliary drain port 63. Therefore, the main drain port 6
Can be set relatively small.
In other words, since it is not necessary to form a large opening in the closed container 11, it is possible to secure the performance of discharging the hydraulic oil while sufficiently securing the rigidity of the closed container 11.

<Fifth Embodiment> The HST 1 of this embodiment is the same as that shown in FIG.
As shown in FIG. 2, a first auxiliary drain port 63 is formed below the main drain port 6, and a second auxiliary drain port 63 is provided on the other side surface of the closed container 11 facing the first auxiliary drain port 63. An auxiliary drain port 64 is formed.

The plunger block 22 of the hydraulic pump mechanism 2 and the plunger block 3 of the hydraulic motor mechanism 3
A flat guide plate P extending in the horizontal direction is disposed between the guide plate P and the guide plate P.

In the HST 1 of this embodiment, when the output shaft 36 rotates forward, the hydraulic oil is forcibly discharged from the first auxiliary drain port 63 as in the case of the fourth embodiment. That is, the hydraulic oil flowing with the rotation of the plunger block 22 of the hydraulic pump mechanism 2 flows along the upper surface of the guide plate P and is discharged from the first auxiliary drain port 63. Similarly, the hydraulic oil flowing with the rotation of the plunger block 32 of the hydraulic motor mechanism 3 flows along the lower surface of the guide plate P and is discharged from the first auxiliary drain port 63.

On the other hand, when the output shaft 36 reverses, both the plunger block 22 of the hydraulic pump mechanism 2 and the plunger block 32 of the hydraulic motor mechanism 3 rotate counterclockwise in FIG. 12 (solid line in FIG. 12). Arrow)). For this reason, both plunger blocks 22,
A flow of hydraulic oil is generated around the periphery of the line 32 as shown by the arrow indicated by the broken line in FIG.

Plunger block 2 of hydraulic pump mechanism 2
Since the first auxiliary drain port 63 is located on the downstream side of the flow of the hydraulic oil generated by the rotation of Step 2 (the position facing the flow of the hydraulic oil), this hydraulic oil flows along the upper surface of the guide plate P It will flow toward one auxiliary drain port 63. On the other hand, since the second auxiliary drain port 64 is located on the downstream side of the flow of the hydraulic oil generated by the rotation of the plunger block 32 of the hydraulic motor mechanism 3 (the position facing the flow of the hydraulic oil), this hydraulic oil is Along the lower surface of the guide plate P, the second auxiliary drain port 64
Will flow towards. In this way, the hydraulic oil in the sealed container 11 is forcibly discharged by the dynamic pressure acting from each of the plunger blocks 22 and 32.

According to the structure of the present embodiment, auxiliary drain ports 63 and 64 are provided in addition to the main drain port 6, and especially when the output shaft 36 reverses, hydraulic oil is forced from both auxiliary drain ports 63 and 64. It is designed to be discharged. Therefore, the opening area of the main drain port 6 can be set smaller.

<Sixth Embodiment> As shown in FIG. 13, the HST 1 of this embodiment has an auxiliary drain port 63 as in the case of the fourth embodiment. A baffle plate 65 protruding into the closed casing 11 is provided at the upper edge of the auxiliary drain port 63. The baffle plate 65 extends in the horizontal direction from the inner surface of the housing 12, and its distal end portion has a curved surface 65 along the outer peripheral surface shape of the plunger block 22.
a.

With this configuration, when the output shaft 36 rotates forward, a flow of hydraulic oil is generated between the plunger blocks 22 and 32 as indicated by the broken line arrow in FIG. The presence of the baffle 65 causes the hydraulic pump mechanism 2
The hydraulic oil flowing along the outer peripheral surface of the plunger block 22 has the auxiliary drain port 63
Can be changed in the direction of. That is, the hydraulic oil circulating along the plunger block 22 is transferred to the baffle plate 6.
5 can be forced to flow toward the auxiliary drain port 63, and the discharge amount of hydraulic oil from the auxiliary drain port 63 can be increased.

In this embodiment, when the second auxiliary drain port 64 is provided as in the fifth embodiment and the baffle plate 66 shown by the phantom line in FIG.
When the cylinder 6 rotates in the reverse direction, the flow direction of the hydraulic oil flowing along the outer peripheral surface of the plunger block 32 of the hydraulic motor mechanism 3 is changed by the baffle plate 66 to the direction toward the second auxiliary drain port 64 (two points in FIG. 13). (See the arrow indicated by the chain line.) That is, the hydraulic oil to be circulated along the plunger block 32 can be forced to flow toward the second auxiliary drain port 64, and the discharge amount of the hydraulic oil can be further increased.

<Seventh Embodiment> The HST 1 of this embodiment is similar to the HST 1 of FIG.
As shown in FIG. 4, the oil level of the hydraulic oil is always set between the hydraulic pump mechanism 2 and the hydraulic motor mechanism 3. That is, the hydraulic pump mechanism 2 is not immersed in the working oil.

In this embodiment, the position of the drain port 6 is set between the hydraulic pump mechanism 2 and the hydraulic motor mechanism 3 on the side surface of the closed casing 11. For this reason, the height of the oil level O of the working oil is also set between the two mechanisms 2 and 3.

In the HST 1, the hydraulic pump mechanism 2
And a lubricating means for lubricating the operating oil with drops. The lubrication means includes lubrication ports 11c, 11c attached to the upper end of the closed container 11. The lubrication port 11c is connected to the discharge side of the charge pump 4, and a part of the oil discharged from the charge pump 4 is supplied to the lubrication ports 11c, 11c. Drop-shaped hydraulic oil is supplied to the pump mechanism 2 (FIG. 14).
Arrow)).

Therefore, even if the hydraulic pump mechanism 2 is not immersed in the working oil, the lubrication is performed well. The plunger block 22 of the hydraulic pump mechanism 2
Almost no rotation loss due to hydraulic oil occurs. For this reason, the efficiency of HST1 can be significantly improved.

FIG. 15 shows a case where the lubrication port 11c is provided in the center section 13. The direction in which the drop-shaped hydraulic oil is injected from the oil injection port 11c to the hydraulic pump mechanism 2 is indicated by an arrow.

<Eighth Embodiment> In this embodiment, the oil level can be adjusted according to the load of the HST 1 in the seventh embodiment.

The mechanism for adjusting the oil level is such that drain ports 61 and 62 are formed on the side and top surfaces of the housing 12, respectively, as in the third embodiment described above. While draining the hydraulic oil only from the drain port 62, the housing 12
The working oil is discharged only from the drain port 61 on the side surface.

At the time of a high load, the entire inside of the closed container 11 is filled with the hydraulic oil, so that it is not necessary to lubricate the oil from the lubrication port 11c. When the load is low, the oil level is
Is set between the hydraulic motor mechanism 3 and the hydraulic motor mechanism 3, the droplet-shaped hydraulic oil is supplied from the lubrication port 11 c toward the hydraulic pump mechanism 2.

For this reason, according to the present embodiment, the oil level is adjusted according to the load state of the HST 1, that is, the required lubrication performance, so that high lubrication performance is ensured at high load and sufficient lubrication performance is maintained at low load. While ensuring the lubricating performance, the rotation loss when the plunger block 22 rotates is greatly reduced, so that H
The efficiency of ST1 can be improved.

<Ninth Embodiment> In the ninth embodiment, in the eighth embodiment, the HST 1 is provided with a cooling means for cooling hydraulic oil.

More specifically, as shown in FIG. 16, a cooling water flow path 7 is formed in the upper half of the housing 12 (the part facing the hydraulic pump mechanism 2), and the cooling water flows through the cooling water flow path 7. To cool the hydraulic oil. That is, the flange-shaped projection 71 is formed on the upper half of the housing 12, and the lid 72 is attached over the projection 71. Thereby, the outer surface of the housing 12 and the lid 7
A cooling water passage 7 is formed between the cooling water passage 2 and the cooling water passage 2. Further, a radiation fin 73 is provided on the outer surface of the housing 12 located in the cooling water flow path 7 in order to enhance heat radiation.

[0108] Cooling water always flows through the cooling water flow path 7. At the time of a high load in which the temperature of the hydraulic oil tends to increase, the hydraulic oil is filled up to the upper end portion in the closed casing 11, so that the hydraulic oil is cooled by the cooling water. At a low load in which the temperature of the hydraulic oil is hard to increase, the oil level is reduced, and thus the hydraulic oil is hardly cooled by the cooling water.

For this reason, regardless of the load state of the HST1, the temperature of the hydraulic oil is always kept substantially constant (for example, 50 ° C. to 80 ° C.).
) And good lubrication performance can be obtained.

In this embodiment, the case where the hydraulic pump mechanism 2 and the hydraulic motor mechanism 3 are arranged side by side in the vertical direction has been described. Applicable.

<Tenth Embodiment> In the ninth embodiment, the cooling water passage 7 is formed in the upper half of the housing 12. In this embodiment, as shown in FIG.
The cooling water flow path 7 is formed in the lower half of the above.

In this embodiment, when the load is high, the cooling water is caused to flow through the cooling water passage 7 to cool the hydraulic oil, while when the load is low, the supply of the cooling water to the cooling water passage 7 is stopped so that the cooling of the hydraulic oil is not performed. I have to.

-Other Embodiments- In each of the above embodiments, the case where the present invention is applied to the HST in which the hydraulic pump mechanism 2 and the hydraulic motor mechanism 3 are accommodated in one closed container 11 has been described. The present invention is not limited to this, and can also be applied to an HST in which a hydraulic pump mechanism and a hydraulic motor mechanism are housed in independent containers. Further, the present invention can be applied to other fluid machines such as a hydraulic device such as a hydraulic pump and a hydraulic motor.

The drain port 6 for discharging the hydraulic oil in the sealed container 11 is not necessarily provided in the housing 12, but may be provided in the center section 13 or may be provided in both the housing 12 and the center section 13. Good.

<Experimental Example> Hereinafter, an experiment performed to confirm the effect of reducing the rotation loss will be described. In this experiment, the conventional HST (circuit internal pressure 2 MPa) and the seventh
The HST1 shown in the embodiment was performed by measuring the input power while increasing the engine speed.

FIG. 18 shows the result. In the figure, the solid line indicates the conventional HST, and the broken line indicates the HTS 1 according to the present embodiment. As described above, it was confirmed that the HST 1 according to the present embodiment requires less input power as the engine speed is higher than the conventional one. For example, 3000 rpm
In the case of rpm, the input power is about 6
It was confirmed that 0% was enough.

[0117]

As described above, according to the present invention, in the fluid machine in which the rotating body rotates in the container storing the working oil, the oil level of the working oil is set to a position lower than the upper edge of the rotating body. You have set. For this reason, when the rotating body rotates in the container, the rotation loss is reduced as compared with the case where the whole rotating body is immersed in the hydraulic oil, and the power loss of the fluid machine is reduced. be able to.

Further, when an oil level adjusting mechanism for varying the oil level according to the load acting on the rotating body is provided,
In particular, it is possible to appropriately adjust the oil level according to a high load at which lubrication performance is required and a low load at which lubrication performance is not so required as compared with the high load. That is, a state in which lubrication performance is prioritized and a state in which rotation loss reduction is prioritized can be switched according to the load, and a highly practical fluid machine can be provided.

Further, when the oil level is set at a low position, when the lubricating means for injecting the hydraulic oil toward the rotating body is provided, the lubricating performance can be improved while maintaining the effect of reducing the rotational loss. It becomes possible to plan.

In addition, when a cooling means for cooling the hydraulic oil in the container at a high load is provided, deterioration of the lubricating performance due to a rise in the temperature of the hydraulic oil can be avoided, and high reliability can be obtained. Lubrication operation can be maintained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an internal configuration of HST1.

FIG. 2 is a cross-sectional view of a position corresponding to line II-II in FIG.

FIG. 3 is a diagram schematically showing an operation circuit of the HST.

FIG. 4 is a view corresponding to FIG. 2, showing a first embodiment of the oil level setting structure;

FIG. 5 is a diagram corresponding to FIG. 1 showing a first embodiment of the oil level setting structure;

FIG. 6 is a diagram for explaining a lower limit value of a drain port opening diameter.

FIG. 7 is a diagram corresponding to FIG. 2, showing a second embodiment of the oil level setting structure.

FIG. 8 is a diagram corresponding to FIG. 2, showing a third embodiment of the oil level setting structure.

FIG. 9 is a diagram corresponding to FIG. 2, showing a modification of the third embodiment of the oil level setting structure.

FIG. 10 is a view corresponding to FIG. 2, showing another modified example of the third embodiment of the oil level setting structure.

FIG. 11 is a view corresponding to FIG. 2, showing a fourth embodiment of the oil level setting structure.

FIG. 12 is a view corresponding to FIG. 2, showing a fifth embodiment of the oil level setting structure.

FIG. 13 is a diagram corresponding to FIG. 2, showing a sixth embodiment of the oil level setting structure.

FIG. 14 is a diagram corresponding to FIG. 2, showing a seventh embodiment of the oil level setting structure.

FIG. 15 is a view corresponding to FIG. 1 showing a modification of the seventh embodiment of the oil level setting structure.

FIG. 16 is a view corresponding to FIG. 2, showing a modification of the ninth embodiment of the oil level setting structure.

FIG. 17 is a diagram corresponding to FIG. 2, showing a modified example of the tenth embodiment of the oil level setting structure.

FIG. 18 is a diagram showing the results of an experiment performed to confirm the effect of reducing rotation loss.

[Explanation of symbols]

 Reference Signs List 1 HST 11 Sealed container 11a Air hole (opening) 11c Lubrication port (lubrication means) 2 Hydraulic pump mechanism 3 Hydraulic motor mechanism 22, 32 Plunger block (rotary body) 5 Recovery pipe (discharge path) 6, 61, 62 drain port ( (Hydraulic oil discharge hole) 63, 64 Auxiliary drain port 65, 66 Baffle plate P Guide plate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D042 AA05 AB12 BA02 BA05 BA08 BA17 BA18 3H070 AA01 BB04 CC21 CC27 DD96 3J053 AA01 AB02 AB42 FB07

Claims (20)

[Claims] 1. A fluid machine in which a rotating body rotates in a container in which the working oil is stored, wherein the oil level of the working oil is set at a position lower than an upper end edge of the rotating body. Fluid machine with rotating body. 2. The fluid machine provided with a rotating body according to claim 1, wherein the fluid machine is configured as a hydrostatic transmission including a hydraulic pump mechanism and a hydraulic motor mechanism in a container, wherein the hydraulic pump mechanism and the hydraulic motor mechanism are arranged vertically. The rotating body is a plunger block in a mechanism located on the upper side of the two mechanisms, and an oil level of hydraulic oil is higher than an upper edge of the plunger block. A fluid machine comprising a rotating body, wherein the fluid body is also set at a lower position. 3. A fluid machine comprising a rotating body according to claim 1, wherein the fluid machine is configured as a hydrostatic transmission having a hydraulic pump mechanism and a hydraulic motor mechanism in a container, wherein the hydraulic pump mechanism and the hydraulic motor mechanism are horizontal. The rotating body is a plunger block provided in each of the two mechanisms, and an oil level of hydraulic oil is set at a position lower than an upper end edge of the plunger block. A fluid machine provided with a rotating body. 4. A fluid machine provided with a rotating body according to claim 1, wherein the rotating machine is configured as a hydraulic device having a hydraulic pump mechanism or a hydraulic motor mechanism alone in a container, and the rotating body is provided with the hydraulic pump mechanism or the hydraulic system. A plunger block provided in a motor mechanism, wherein a fluid level of hydraulic oil is set at a position lower than an upper end edge of the plunger block. 5. A fluid machine comprising a rotating body according to claim 1, wherein a hydraulic oil discharge hole is formed at a position lower than an upper end edge of the rotating body on a container wall, and the hydraulic oil discharge hole is formed. A fluid machine provided with a rotating body, wherein an oil level is set at a position lower than an upper end edge of the rotating body by discharging hydraulic oil from the hole. 6. A fluid machine having a rotating body according to claim 5, wherein the diameter of the hydraulic oil discharge hole is such that the sum of the pressure inside the container and the pressure head of the hydraulic oil in the container leads to the hydraulic oil discharge hole. A fluid machine having a rotating body, wherein the fluid machine is set to be larger than a back pressure of a discharge path. 7. The rotating machine according to claim 5, wherein the formation position of the hydraulic oil discharge hole is set at a position facing a side surface of the rotating body on a container wall surface. Fluid machinery with. 8. A fluid machine having a rotating body according to claim 5, wherein an opening for opening the space inside the container to the atmosphere is formed at a position near an axis of the rotating body in the container. Fluid machine with body. 9. A fluid machine in which a rotating body rotates in a container in which hydraulic oil is stored, comprising: an oil level adjusting mechanism for adjusting an oil level of the hydraulic oil; A fluid machine having a rotating body, wherein the fluid level is switched according to a load acting on the rotating body. 10. A fluid machine provided with a rotating body according to claim 9, wherein a plurality of hydraulic oil discharge holes are formed in the container, and these hydraulic oil discharge holes are formed at a relatively low position of the container. And a second hole formed at a relatively high position in the container. When the load acting on the rotating body is less than a predetermined value, the first hole is A fluid machine equipped with a rotating body, characterized in that the hydraulic oil is discharged from only the second hole when the load exceeds a predetermined value while the hydraulic oil is discharged from the fluid. 11. The fluid machine provided with a rotating body according to claim 10, further comprising an oiling means for injecting the working oil toward the rotating body when the operating oil is discharged from the first hole. Fluid machine provided with a rotating body. 12. A fluid machine provided with a rotating body according to claim 10 or 11, further comprising cooling means capable of cooling hydraulic oil in a container. 13. The fluid machine provided with a rotating body according to claim 12, wherein the cooling means performs a cooling operation of the hydraulic oil only when the hydraulic oil is discharged only from the second hole. A fluid machine provided with a rotating body characterized by the above-mentioned. 14. A fluid machine including a rotating body according to claim 13, wherein the fluid machine is configured as a hydrostatic transmission including a hydraulic pump mechanism and a hydraulic motor mechanism in a container, wherein the hydraulic pump mechanism and the hydraulic motor mechanism are arranged vertically. A fluid machine equipped with a rotating body, which is arranged so as to be adjacent to each other in a direction or an oblique direction, and wherein the cooling means is configured to cool only an upper portion of the container. 15. The hydraulic machine comprising the rotating body according to claim 2, wherein the oil level of the hydraulic oil is set at an intermediate position between the hydraulic pump mechanism and the hydraulic motor mechanism. A fluid machine having a rotating body, characterized by comprising an oiling means for injecting hydraulic oil toward a mechanism located at an upper side among the above. 16. A fluid machine having a rotating body according to claim 15, wherein the lubricating means is configured to perform lubrication when a load acting on the rotating body exceeds a predetermined value. Fluid machine with rotating body. 17. The fluid machine provided with a rotating body according to claim 5, wherein the hydraulic oil discharge hole is provided for a flow of hydraulic oil generated in a circumferential direction of the rotating body due to rotation of the rotating body in the hydraulic oil. A fluid machine provided with a rotating body, which is open to face. 18. A fluid machine provided with a rotating body according to claim 2, wherein the plunger block of the hydraulic pump mechanism and the plunger block of the hydraulic motor mechanism rotate in directions opposite to each other, and are sandwiched between the two plunger blocks. A fluid machine comprising a rotating body, wherein a hydraulic oil discharge hole is formed so as to face the flow of hydraulic oil generated in the hydraulic fluid, and the hydraulic oil is discharged from the hydraulic oil discharge hole. 19. A fluid machine comprising a rotating body according to claim 2, wherein a guide plate for partitioning a space in which the plunger blocks are disposed is provided between the plunger block of the hydraulic pump mechanism and the plunger block of the hydraulic motor mechanism. When the plunger block of the hydraulic pump mechanism and the plunger block of the hydraulic motor mechanism rotate in the same direction,
The position opposing the flow of hydraulic oil generated in the circumferential direction of the plunger block due to the rotation of the plunger block of the hydraulic pump mechanism and the position opposing the flow of hydraulic oil generated in the circumferential direction of the plunger block due to the rotation of the plunger block of the hydraulic motor mechanism A fluid machine having a rotating body, wherein a hydraulic oil discharge hole is formed at each of the positions, and hydraulic oil is discharged from the hydraulic oil discharge hole. 20. A fluid machine provided with a rotating body according to claim 17, further comprising a baffle plate for directing a flow direction of hydraulic oil flowing along an outer peripheral surface of the rotating body toward a hydraulic oil discharge hole. A fluid machine having a rotating body.