JPH05172042A - Rotary machine of radial piston type - Google Patents

Abstract

PURPOSE:To provide a radial piston pump capable of increasing self-priming capability, and delivering two independent types of fluid with a short radial length. CONSTITUTION:Two types of cylinder chambers 15a and 15b having different depth are alternately and radially arranged in a cylinder block 6, and passages 17a and 17b continuous from each of the chambers 15a and 16b to a valve plate 10 are provided. In addition, inlet ports 21a and 21b and outlet ports 22a and 22b are so formed through the valve plate 10 as to be continuous to outlet passages 19a and 19b. Also, each of the cylinder chambers 15a and 15b is fitted with a balance piston 11. As a result the axial direction length can be made smaller than the case of a radial piston pump having two rows of a cylinder group in an axial direction. Furthermore, a pressure balance in an axial direction can be maintained with the balance piston 11, and the ports of the valve plate 10 can be made larger, thereby improving self-priming capability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radial piston type rotary machine capable of enlarging the valve plate port to enhance self-priming performance and capable of forming a multiplicity of cylinders with a short axial dimension. Regarding

[0002]

2. Description of the Related Art In recent years, pumps for small construction machines have been replaced by multiple gear pumps by multiple piston pumps. As a conventional multiple piston pump, there is one in which a plurality of pumps are simply connected, but it has a problem in space for mounting the pump of the main engine because of its large size. Therefore,
JP-A-52-35304 and JP-A-1-26736
As disclosed in Japanese Patent Publication No. 7, a pump has been proposed in which a plurality of independent discharge amounts are taken out from one pump to reduce the size of the pump. FIG. 4 is a view showing a plane and a cross section of a cylinder block and a valve plate of an axial piston pump disclosed in Japanese Patent Laid-Open No. 52-35304 (the Japanese Patent Laid-Open No. 1-267367 also has substantially the same structure). The description is omitted here because it is one.) This axial piston pump has a valve plate 43 having one suction port 41 and two discharge ports 42a and 42b, cylinder chambers 44a and 44b, and the cylinder chambers 44a and 44b, respectively. 3 to communicate with ports 42a and 42b
Cylinder block 46 having two passages 45a, 45b
Is equipped with. Each of the passages 45a and 45b is arranged in three concentric circles with different radii. Then, from the suction port 41 through the passage 45a, the cylinder chamber 44a
The fluid sucked into the discharge port 42a is discharged from the discharge port 42a, and the fluid sucked into the cylinder chamber 44b from the suction port 41 through the passage 45b is discharged from the discharge port 42b. I am able to work. The conventional axial piston pump described above has a limitation in shortening the axial dimension because of the axial original structure of arranging the pistons in the axial direction. As a pump having a short axial dimension, there is a radial type pump, and conventionally, a dual radial piston pump as shown in FIG. 5 has been proposed.
This radial piston pump is provided with two groups of cylinder groups 53a and 53b arranged in the axial direction on a cylinder block 52 that is driven to rotate by a main shaft 51, and suction passages 54a and 54b and discharge passages for each cylinder group 53a and 53b. Passages 55a, 55b and valve plates 56a, 56b are provided.

[0003]

However, this radial piston pump has two cylinder groups 53a and 5a.
3b is arranged in the axial direction, and each cylinder group 53a,
Intake passages 54a, 54b and discharge passage 55 leading to 53b
Since a and 55b are provided on opposite sides in the axial direction,
There is also the drawback that the axial dimension becomes long.

Further, both the axial piston pump shown in FIG. 4 and the radial piston pump shown in FIG. 5 are provided with a valve plate in the fluid passage.
Due to the restriction of (relationship between pressing force and diverging force), the port of the valve plate cannot be made large, resulting in poor self-priming performance and difficulty in operating at high speed. This drawback is the same in the case of a single pump. Further, the above-mentioned drawbacks are also applicable to a piston motor having a similar structure (a multiple piston motor can change the speed in multiple stages by changing the connection relationship of the inlet port to the fluid source). Therefore, an object of the present invention is to provide a radial piston type rotary machine capable of enlarging the port of the valve plate to enhance the self-priming performance, and capable of providing multiple units with a short axial dimension. Especially.

[0005]

In order to achieve the above object, the radial piston type rotary machine of the first aspect of the invention has a Linder block 6 rotatably supported in casings 1 and 2, the casing 2 and the casing 2. A fixed valve plate 10 provided between one end surface of the cylinder block 6 and a plurality of cylinder chambers 15 provided in the radial direction of the cylinder block 6.
each passage 1 communicating with each of the cylinder chambers 15a and 15b, which includes a piston 7 that is fitted in a and 15b and is reciprocally movable.
7a and 17b are concentrically opened at one end surface of the cylinder block 16 and the passages 17a and 1 are provided in the valve plate 10.
Arc-shaped inlet ports 21a, 21 in which 7b are alternately communicated
b and outlet ports 22a, 22b are provided, and on the other end surface side of the cylinder block 6, the cylinder chambers 15a, 1
A balance piston 11 for pressing the cylinder block 6 toward the valve plate 10 in response to the pressure of 5b is provided.

The radial piston type rotary machine according to the second aspect of the present invention includes a Linda block 6 which is rotatably supported in the casings 1 and 2, and an intermediate portion between the casing 2 and one end surface of the cylinder block 6. Fixed valve plate 10 installed
And a plurality of cylinder chambers 15a, 15b provided in the radial direction of the cylinder block 6 and reciprocally movable pistons 7, and the plurality of cylinder chambers 15a, 15b.
Are divided into a first group and a second group, and a first passage 17a communicating with the cylinder chamber 15a of the first group and a second passage 17b communicating with the cylinder chamber 15b of the second group have different radii on one end surface of the cylinder block 16. Arc-shaped inlet ports 21a, 2 that open respectively on the concentric circles and communicate with the valve plate 10 by the first and second passages 17a, 17b.
1b and an arc-shaped first outlet port 22a that communicates with the first passage 17a and an arc-shaped second outlet port 22b that communicates with the second passage 17b, respectively. Each cylinder chamber 15a, 1
A balance piston 11 for pressing the cylinder block 6 toward the valve plate 10 in response to the pressure of 5b is provided.

The radial piston type rotary machine according to the third aspect of the present invention includes a Linder block 6 which is rotatably supported in the casings 1 and 2, and an intermediate portion between the casing 2 and one end surface of the cylinder block 6. Fixed valve plate 10 installed
And a plurality of cylinder chambers 15a, 15b provided in the radial direction of the cylinder block 6 and reciprocally movable pistons 7, and the plurality of cylinder chambers 15a, 15b.
Are divided into a first group and a second group, and a first passage 17a communicating with the cylinder chamber 15a of the first group and a second passage 17b communicating with the cylinder chamber 15b of the second group have different radii on one end surface of the cylinder block 16. The first inlet port 21a and the second inlet port 21b, which are in the shape of an arc and which communicate with the first passage 17a and the second passage 17b, respectively, are opened on the respective concentric circles and are communicated with the second inlet port 21b. Arc-shaped outlet ports 22a and 22b, which communicate with the first and second passages 17a and 17b, are provided, and the cylinder chamber 15 is provided on the other end surface side of the cylinder block 6.
A balance piston 11 is provided for pressing the cylinder block 6 toward the valve plate 10 side by receiving the pressures a and 15b.

[0008]

The radial piston type rotary machine of the first invention is a pump or a motor. In the case of a pump, the rotation of the cylinder block 6 causes the piston 7 to move into the cylinder chamber 15a,
15b is slid in the radial direction, and the inlet port 21 of the valve plate 10 is
a, 21b through passages 17a, 17b to the cylinder chamber 15
Intake fluid into a and 15b, and pass the inhaled fluid to passage 1
Outlet ports 22a, 22b of the valve plate 10 via 7a, 17b
Discharge from. In the case of a motor, the fluid supplied from the inlet ports 21a, 21b of the valve plate 10 to the cylinder chambers 15a, 15b via the passages 17a, 17b pushes the piston 7, thereby rotating the cylinder block 6,
It is discharged from the outlet ports 22a, 22b of the valve plate 10 through the passages 17a, 17b by the reaction force of the piston 7.
Although fluid pressure acts in the axial direction by the fluid passing through the inlet ports 21a, 21b and the outlet ports 22a, 22b of the valve plate 10, the balance piston 11 acts to balance the pressure in the axial direction (the pressing force and the separating force). (Relationship) is maintained, and therefore, the inlet ports 21a and 21b of the valve plate 10 can be enlarged, the self-priming performance is improved, and high-speed operation becomes possible. Further, since it is a radial piston type, the axial dimension can be shortened.

The radial piston type rotary machine of the second invention is a twin pump capable of obtaining two discharge flows. The rotation of the cylinder block 6 causes the piston 7 to move into the cylinder chamber 15
a, 15b in the radial direction, from the inlet ports 21a, 21b of the valve plate 10 to the first group of cylinder chambers 15a via the first passage 17a and to the second group of cylinder chambers 15b via the second passage 17b. Inhale fluid into each.
Then, the fluid sucked into the cylinder chamber 15a of the first group is discharged from the first outlet port 22a of the valve plate 10 through the first passage 17a, and the fluid sucked into the cylinder chamber 15b of the second group is discharged into the second passage 17b. Through valve plate 1
Discharge from 0 second outlet port. Therefore, two discharge streams are obtained. Further, similarly to the first aspect of the invention, the balance piston 11 functions to maintain the axial pressure balance,
The inlet ports 21a and 21b of the valve plate 10 can be made large, the self-priming performance is improved, and high speed operation is possible. Further, since it is of a radial piston type and two discharge flows are discharged from the same axial direction side through one valve plate 10, it is possible to form a twin pump having a short axial direction.

The radial piston type rotary machine according to the third aspect of the present invention is a double motor capable of changing the speed in two stages. The fluid is supplied to the first inlet port 21 a or the second inlet port 21 of the valve plate 10.
Supply from either one of b. First inlet port 21a
Is supplied to the first group of cylinder chambers 15a through the first passage 17a, pushing the piston 7,
As a result, after the cylinder block 6 is rotated, it is discharged from the outlet ports 22a and 22b of the valve plate 10 through the first passage 17a by the reaction force of the piston 7. The fluid supplied from the second inlet port 21b is supplied to the second group of cylinder chambers 15b through the second passage 17b and pushes the piston 7, thereby rotating the cylinder block 6 and then the reaction force of the piston 7. Is discharged from the outlet ports 22a, 22b of the valve plate 10 through the second passage 17b.
The rotation speed can be changed in two stages by switching the supply of the fluid between the supply from both the first inlet port 21a and the second inlet port 21b and the supply from either one. Further, similarly to the first aspect of the invention, the balance piston 11 keeps the axial pressure balance, the inlet ports 21a and 21b of the valve plate 10 can be enlarged, the self-priming performance is improved, and high-speed operation becomes possible. .. Also,
Since it is a radial piston type, a two-axis motor with a short axial direction is possible.

[0011]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. 1 is a sectional view of an eccentric type dual radial piston pump according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 (a) is a rear side view of a cylinder block of this piston pump. 3 (b) is a rear side view of the valve plate of this piston pump. 1 and 2, 1 is a front casing, 2 is a rear casing, 3 is a rotating shaft supported by bearings 4 and 5 by the front casing 1 and the rear casing 2, respectively, and 6 is a spline on the rotating shaft 3. The fitted cylinder block, 7 is a piston radially inserted into the cylinder block 6, 8 is a piston shoe fitted in the head of the piston 7, 9 is a cam ring eccentrically provided with respect to the cylinder block, and 10 is A valve plate 11 fixed to the rear casing 2 and in sliding contact with the rear end face of the cylinder block 6 is a balance piston.

The piston 7 is slidably fitted in two cylinder chambers 15a, 15b of five different depths, each of which is alternately arranged in the circumferential direction, and is externally mounted by springs 16a, 16b. The piston shoe 8 is pressed against the cam ring 9 by being urged in the direction. And
As the cylinder block 6 rotates, it rotates together with the piston shoe 8 inscribed in the cam ring 9 and reciprocates in the radial direction. The cylinder block 6 also has a passage 17 for each of the cylinder chambers 15a and 15b which leads from the cylinder chamber to the valve plate 10.
a and 17b. The passages 17a communicating with the five cylinder chambers 15a having a short depth and the passages 17b communicating with the cylinder chambers 15b having a long depth are each provided with a radius as shown in FIG. 3 (a). They are arranged on different concentric circles. The rear casing 2 has one fluid inlet passage 18 and two fluid outlet passages 19a, 19b.
And the valve plate 10 includes the fluid inlet passage 18
Arc-shaped suction ports 21a, 21b for guiding the fluids from the respective channels to the passages 17a, 17b and the passages 17a, 1b.
The fluid from the fluid outlet passages 19a, 1
It has arc-shaped discharge ports 22a and 22b leading to 9b. The cylinder block 6 also communicates with the cylinder chambers 15a and 15b via passages 23a and opens at the front end face of the cylinder block 6 to axially move the balance piston 11 in the axial direction. It has a balance piston chamber 23 slidably fitted therein. The balance piston 11 is a spring 2
4 is urged forward by 4 to be pressed against the seat plate 25 press-fitted into the front casing 1, and has a gap 26 between the seat plate 25 and the gap 26 and the balance piston chamber. It has a hole 27 for communicating 23.

In the above structure, when the rotating shaft 3 is driven by a motor (not shown), the cylinder block 6 rotates together with the rotating shaft 3, and the piston 7 rotates accordingly. The piston 7 moves toward the spring 16 as the distance between the cylinder block 6 and the cam ring 9 increases.
The urging force of a, 16b causes the fluid to move outward, thereby allowing the fluid from the outside to flow from the fluid inlet passage 18 to the valve plate 10
While the air is sucked into the cylinder chambers 15a, 15b through the suction ports 21a, 21b and the passages 17a, 17b, the springs 16a, 16b are caused by the cam rings 9 as the distance between the cylinder block 6 and the cam ring 9 approaches.
It is pushed toward the center against the urging force of
The fluid sucked into the cylinder chambers 15a, 15b is supplied to the passages 17a, 17b and the discharge ports 22a, 22 of the valve plate 10.
b, the fluid is discharged to the outside through the fluid outlet passages 19a and 19b. That is, from the fluid inlet passage 18 to the cylinder chamber 15
The fluid sucked into a is discharged from one of the fluid outlet passages 19a, and the fluid sucked into the cylinder chamber 15b from the fluid inlet passage 18 is discharged from the other fluid outlet passage 19b. You can get the flow.

The fluid sucked into the cylinder chambers 15a and 15b flows into the balance piston chamber 23 through the passage 23a and fills the clearance 26 through the hole 27 of the balance piston 11. The balance piston 11 moves forward due to fluid pressure generated by the area difference between the sectional area of the gap 26 and the sectional area of the balance piston chamber 23.
Pressed on 5. The cylinder block 6 is pressed against the valve plate 10 by the fluid pressure applied to the balance piston chamber 23, and the deviation from the valve plate 10 is prevented. Since the pressure balance in the axial direction is maintained in this way, the suction ports 21a and 21b of the valve plate 10 can be made large, the self-priming performance is improved, and high-speed operation is possible. In addition, this dual radial piston pump, in order to obtain two independent discharge flows,
The piston 7 is radially inserted into the cylinder block 6, the valve plate 10 is provided on one side (rear side) of the cylinder block 6, and two fluid outlet passages are provided on the rear casing side.
As shown in the conventional example, the two cylinder groups are arranged in the axial direction, and the discharge passages leading to the cylinder groups are not provided on the opposite sides in the axial direction. Moreover, the axial dimension can be shortened, and it is very effective for small construction machines with a small pump installation space.

Although the above embodiment has been described with respect to the dual radial piston pump, it has a similar structure and a speed of 2
It can be a double radial piston motor that can be switched in stages. In this case, the fluid outlet passages 19a, 19b
Is used as the fluid inlet passage, and the supply of the fluid may be switched between the supply to the two fluid inlet passages and the supply to either one of them. In addition, by providing multiple types of cylinder chambers with different depths and providing the same number of fluid outlet passages and valve plate outlet ports (in the case of a motor, fluid inlet passages and valve plate inlet ports), the axial dimension It is possible to realize a multi-pump or multi-motor having three or more stations with a short self-suction performance. In addition, a single pump or motor in which the depths of the cylinder chambers are all the same is also possible, and the axial dimension can be shortened as compared with the axial type, and the self-priming performance is improved due to the balance piston.

[0016]

As is apparent from the above, the radial piston type rotary machine according to the first aspect of the present invention includes a Linda block rotatably supported in a casing and a space between the casing and one end surface of the cylinder block. An intervening fixed valve plate and a reciprocating piston fitted in a plurality of cylinder chambers provided in the radial direction of the cylinder block are provided.
Each passage communicating with each of the cylinder chambers is opened concentrically on one end face of the cylinder block, and the valve plate is provided with an arc-shaped inlet port and an outlet port in which the passages are alternately communicated with each other. Since the balance piston that presses the cylinder block to the valve plate side by receiving the pressure of each cylinder chamber is provided on the other end surface side, the following effects are obtained. Since it is a radial piston type, the axial dimension can be shortened compared to the axial piston type. Since the balance piston is provided, the pressure balance in the axial direction is maintained. Therefore, the inlet port of the valve plate can be increased, the self-priming performance is improved, and the speed can be increased.

A radial piston type rotary machine according to a second aspect of the present invention is a fixed valve plate provided between a Linder block rotatably supported in a casing and the casing and one end surface of the cylinder block. And a reciprocating piston fitted in a plurality of cylinder chambers provided in the radial direction of the cylinder block, and dividing the plurality of cylinder chambers into first and second groups into a first group of cylinder chambers. A first passage communicating with the second chamber and a second passage communicating with the second group of cylinder chambers are opened in concentric circles with different radii on one end surface of the cylinder block, and the first and second passages communicate with the valve plate. A circular arc-shaped inlet port communicating with the first passage, and a circular arc-shaped second output port communicating with the second passage. On the other end surface side of the block, a balance piston for pressing the cylinder block to the valve plate side by receiving the pressure of each cylinder chamber is provided. Therefore, in addition to the effect of the first invention, the axial dimension is short. The effect is that a piston pump that outputs two independent discharge flows can be obtained.

A radial piston type rotary machine according to a third aspect of the present invention is a fixed valve plate provided between a Linder block rotatably supported in a casing and the casing and one end surface of the cylinder block. And a reciprocating piston fitted in a plurality of cylinder chambers provided in the radial direction of the cylinder block, and dividing the plurality of cylinder chambers into first and second groups into a first group of cylinder chambers. A first passage communicating with the second chamber and a second passage communicating with the second group of cylinder chambers are respectively opened in concentric circles having different radii on one end face of the cylinder block, and the valve plate is connected to the first passage in an arc shape. The first inlet port of the arc and the second inlet port of an arc shape communicating with the second passage and the first
And a circular arc-shaped outlet port communicating with the second passage, and a balance piston for pressing the cylinder block to the valve plate side by receiving the pressure of each cylinder chamber is provided on the other end surface side of the cylinder block. Therefore, in addition to the effect of the first invention, there is an effect that a piston motor having two independent intake fluids having a short axial dimension can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a dual radial piston pump according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a cylinder block (a) and a valve plate of the above pump.
It is a rear side view of (b).

FIG. 4 is a diagram showing a cylinder block and a valve plate of a conventional dual axial piston pump.

FIG. 5 is a sectional view of a conventional dual radial piston pump.

[Explanation of symbols]

1 ... Front casing, 2 ... Rear casing, 3 ... Rotating shaft, 6 ... Cylinder block, 7 ... Piston, 10 ... Valve plate, 11 ... Balance piston, 15a, 15b ... Cylinder chamber, 17a, 17b ... Passage, 18 ... Fluid Entrance passage, 1
9a, 19b ... Fluid outlet passage, 21a, 21b ... Suction port, 22a, 22b ... Discharge port, 23 ... Balance piston chamber.

Claims (3)

[Claims] 1. A Linder block (6) rotatably supported in a casing (1, 2), and a fixed block provided between the casing (2) and one end surface of the cylinder block (6). Each of the cylinder chambers includes a valve plate (10) and a reciprocating piston (7) fitted in a plurality of cylinder chambers (15a, 15b) provided in the radial direction of the cylinder block (6).
Each of the passages (17a, 17b) communicating with (15a, 15b) is opened concentrically at one end face of the cylinder block (16),
The valve plate (10) is provided with arc-shaped inlet ports (21a, 21b) and outlet ports (22a, 22b) in which the passages (17a, 17b) are alternately communicated, and the cylinder block is provided.
On the other end surface side of (6), the above cylinder chambers (15a, 15b)
The cylinder block (6) receives the pressure of
A radial piston type rotary machine characterized in that a balance piston (11) for pressing on the (10) side is provided. 2. A Linder block (6) rotatably supported in the casing (1, 2) and a fixed block provided between the casing (2) and one end surface of the cylinder block (6). A valve plate (10) and a reciprocating piston (7) fitted into a plurality of cylinder chambers (15a, 15b) provided in the radial direction of the cylinder block (6) are provided, and the plurality of cylinder chambers ( 15a, 15b) into first and second groups,
First passage leading to the cylinder chamber (15a) of the first group
(17a) and a second passage (17b) communicating with the second group of cylinder chambers (15b) are respectively opened on one end surface of the cylinder block (16) in concentric circles with different radii, and the valve plate (10) The first and second passages (17a, 17b)
Arc-shaped inlet ports (21a, 21b) communicating with each other and the arc-shaped first outlet port communicating with the first passage (17a)
(22a) and the second passage (17b) communicate with each other, the arc-shaped second outlet port (22b) is provided, and the cylinder chambers (15a, 15a,
A radial piston type rotary machine comprising a balance piston (11) for pressing the cylinder block (6) toward the valve plate (10) side under the pressure of 15b). 3. A Linder block (6) rotatably supported in the casing (1, 2), and a fixed block provided between the casing (2) and one end surface of the cylinder block (6). A valve plate (10) and a reciprocating piston (7) fitted into a plurality of cylinder chambers (15a, 15b) provided in the radial direction of the cylinder block (6) are provided, and the plurality of cylinder chambers ( 15a, 15b) into first and second groups,
First passage leading to the cylinder chamber (15a) of the first group
(17a) and a second passage (17b) communicating with the second group of cylinder chambers (15b) are respectively opened on one end surface of the cylinder block (16) in concentric circles with different radii, and the valve plate (10) A first arc-shaped inlet port (21a) communicating with the first passage (17a) and a second arc-shaped inlet port (21b) communicating with the second passage (17b), and the first and second Arc-shaped outlet ports (22a, 22b) communicating with the passages (17a, 17b) are provided respectively, and the cylinder chambers (15a, 15a,
A radial piston type rotary machine comprising a balance piston (11) for pressing the cylinder block (6) toward the valve plate (10) side under the pressure of 15b).