JPS5843588B2 - radial piston capacity - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a cylinder block containing a piston for stroke movement in a cylinder bore and rotating on a strut pin, the control pins having a cylinder block diametrically opposed to each other. and cooperating with the opening of the cylinder hole 2
two control openings are formed, the control openings being separated from each other by transverse webs, and a groove extending parallel to the control openings and circumferentially of the control pin is formed; It concerns radial piston machines (pumps or motors) of the type in which a pressure field acts in the area of the groove.

The force exerted by the pressure medium in the cylinder bore on the piston produces a reaction force, one component of which presses the cylinder block against the transverse web facing the inner dead center of the piston movement, and the other component forces the cylinder Crimp the block to the control pin in the area of the high pressure side control opening.

Such forces are compensated satisfactorily by the static and/or dynamic pressure field formed in said area of the control pin.

Grooves are formed on both sides of the control entrance, and these grooves extend approximately the same circumferential length as the control opening of the control pin, and each side hole extends through the control pin. Radial piston pumps are known which are connected with diametrically opposed control openings.

With this arrangement, a dynamic pressure field is created in the area of the groove, which dynamic pressure field reduces the forces acting on the control pin in the area of the control opening.

Such a pipe has the disadvantage that the forces acting on the transverse web facing the inner dead center of the piston movement are usually compensated only by a dynamic pressure field.

The supporting force of this dynamic pressure field is related to the configuration of the bearing, in particular its dimensions; if the load of the control pin on the web facing the inner dead center is relatively high, said supporting force will be
If the stresses are large and the eccentricity of the cam ring is large, values are required that make it impossible to reduce the size and minimize leakage losses.

The object of the invention is to provide a radial piston machine in which the forces acting on the transverse web of the control pin are compensated with small bearing dimensions even under high loads.

In order to solve this problem, according to the invention, in each transverse web, on each side of the control opening, viewed in the circumferential direction of the control pin, there are two two grooves are formed, which grooves are separated from each other by webs and each have one passage which intersects the straight line connecting the dead points of the piston movement and are identical to the grooves with respect to an outer circumferential line passing through said transverse web. The control openings located on the sides communicate with each other.

This has the advantage that the pressure is significantly increased at the periphery of the dynamic pressure field, whereby the supporting force of the dynamic pressure field can be increased up to several times in relation to the pressure in the grooves of the transverse web.

The load capacity of the control pin can be increased for a given size, or the force can be compensated for with a smaller size of the control pin for a given load.

The invention will now be explained with reference to the illustrated embodiment.

The radial piston machine has an approximately cup-shaped housing 1, which is closed off by a housing cover 2.

A hole 3 extending from the end face of the casing opposite to the casing cover 2 opens into a substantially oval notch 4 of the casing 1 .

A control pin 5 is fixedly arranged in the bore 3 and projects into the recess 4 .

A cylinder block 6 is arranged within the notch 4,
This cylinder holder is rotatably mounted on a control pin 5.

A plurality of radially extending cylinder holes 7 are formed in the cylinder block 6, and a piston 8 is disposed in each of these cylinder holes, and the piston is supported by a cam ring 10 by a sliding shoe 9. There is.

A cam ring 10 is slidably arranged in the recess 4 in a manner not shown in order to change the piston stroke.

The two retaining rings 11 and 12 prevent the sliding shoe 9 from moving away from the cam ring 10.

The drive shaft 13 is supported in a ball bearing 14 within the casing cover 2 and is sealed from the outside by a shaft sealing ring 15.

The end of the drive shaft forms a flange 16 on which two meshing parts are formed which engage in corresponding first slits of the clutch disc 17. , the clutch disc is further held at 90o with respect to the slit.
The cylinder block has two separate slits which are shaped like f, and a meshing part formed on the cylinder block is engaged in these slits, so that the cylinder block cannot rotate relative to the drive shaft 13. combined.

Two diametrically opposed control openings 18 , 19 are formed in the control pin 5 , which cooperate with the opening of the cylinder bore 7 .

A passage 20, which extends partly into the casing 1 and partly into the control pin, opens into the control opening 18, and a passage 21, which also extends partly into the casing 1 and partly into the control pin, opens into the control opening 18. It opens into control opening 19 .

Channels 20 and 21 are used for the inflow or outflow of pressure medium, depending on the type of operation of the machine.

“Details of the longitudinal section supporting the cylinder block of the control pin are shown in exploded view in FIG.

A groove 22, 23 is formed on each side of the control opening 18, which extends parallel to it and in the circumferential direction;
These grooves are shorter than the control opening 18 and are arranged symmetrically thereto.

In the same way, one on each side of the control opening 19.
Two grooves 24, 25 are formed.

A sealing web 26.27 is left in each case between the control opening 18 and the groove 22.23, and the grooves 22, 2
On the side opposite the control opening 18 of 3 there is a support web 28, 2
9 is formed.

Similarly, between the control opening 19 and the grooves 24, 25 a sealing web 30,3=1 remains, while the groove 24°2
On the side opposite the control opening 19 of 5 there is a support web 32.3.
3 is provided.

A ring groove 5' formed in the control pin 5 delimits the longitudinal section of the control pin supporting the cylinder block;
and a control pin press-fitted into the hole 3.
is provided at the location where it transitions to the notch 4.

Each two grooves 22, 24 or 23, 25 located on the same side of the control opening are communicated with each other by a hole 34 or 35 passing through the control pin (see FIG. 3).

Both control openings 18 and 19 have two transverse webs 36
．． They are separated from each other by 37.

The transverse web 36 includes, on both sides of the control opening viewed in the circumferential direction,
Two grooves 40.degree. 41 or 42. separated by webs 38 or 39 and located one after the other.
43 is formed.

Similarly, in the transverse web 37 there are in each case two grooves 46, 47 or 4 separated from each other by a web 44 or 45.
8.49 is formed.

Two grooves each formed one after the other in the transverse web, e.g. 40
The lengths of and 41 are, when viewed in the circumferential direction of the control pin,
Including the webs separating these grooves, such as 38, are greater than the length of the transverse webs in which these grooves are formed.

The outer circumferential line 50 indicating the dead center position of the piston movement is the horizontal web 3
6 through the center of the webs 38.39, while a similar circumferential line 51 runs through the center of the webs 44 on the transverse webs 37.
, 45.

Of the grooves 40 to 43 of the transverse web 36, the groove 40.42 located on the same side with respect to the circumferential line 50 as the control opening 18 is
are respectively connected to the control openings 18 by passages 52,53 extending in the control pins 5, while the outer circumferential line 50
Grooves 41, 43 located on opposite sides of each channel 54.
55, they are respectively connected to the 'f61 leg opening part 19 on the opposite side.

Similarly, the grooves 46, 48 located on the same side of the circumferential line 51 in the transverse web 37 as the control opening 19 are each connected to the control opening 19 by one groove 56, 57 and grooves 47. 49 are respectively connected to the control openings 18 by one passage 58, 59 in each case.

Passages 52-55 and 56-59 extend within the control pin.

Passages 52-55 and 56-59 may be
In order to minimize leakage loss through the grooves in the transverse web located on the outer dead center side, a constriction portion 60 may be provided.

If, during operation of the machine, the cylinder block carries out a rotational movement and the control opening 19 is a high-pressure control opening, the transverse web 36 is located on the dead center side inside the piston movement.

The cylinder block is pressed against the control pin in the area of the transverse web by the force acting on it, so that the gap between the cylinder block and the control pin at this point is diametrically opposed on the outer dead center side of the piston movement. It is narrower than the gap in the horizontal web 37.

By means of the rotating cylinder block 6, the pressure medium is drawn from the high-pressure side control opening 19 and the sealing web 30.31 and the grooves 24, 25 into the narrowed gap in the area of the transverse web 36, so that there is no movement in this area. A pressure field is formed.

From the high-pressure side control opening 19 via channels 54 and 55, the pressure medium under high pressure reaches the grooves 41 and 43 and forms a static pressure field around them, which static pressure field is located between them. Increase the surrounding pressure of the dynamic pressure field.

In the case of the exemplary embodiment shown, the supporting force is therefore increased very significantly, as shown in the diagram in FIG.

In the diagram shown, the ambient static pressure is plotted on the abscissa and the supporting force of a given bearing is plotted on the ordinate.

A curve representing the supporting force of the bearing part is obtained by using the eccentricity E of the stationary bearing part with respect to the rotating bearing part as a parameter.

For example, if the value of the eccentricity E is 19 μm, as occurs in the radial piston machine, a line that rises almost linearly is obtained.

At the high working pressures that are common today, high bearing peripheral pressures are obtained, and with average eccentricity, ffi! [let] A large supporting force of the bearing in the transverse web of the pin is obtained.

If the direction of eccentricity remains the same but the direction of rotation of the cylinder block changes, the control opening 18 becomes the high-pressure side control opening, while the transverse web 36 furthermore becomes the inner dead center side of the piston movement. To position.

In this case, grooves 40, 42 perform the same function as grooves 41 and 43 described above.

When the eccentric direction of the cam ring changes, the transverse web 37 is located on the inner dead center side of the piston movement and the grooves 46 and 48
or 47 and 49, in conjunction with the respective high-pressure side control opening, increase the peripheral pressure of the dynamic pressure field in the transverse web 37.

In short, force compensation takes place in all operating states of the machine.

Such an arrangement of the control pin is particularly suitable for radial piston machines which operate at relatively high pressures and whose cam rings have a large eccentricity.

This is because the two factors are proportional to the magnitude of the force compensated by the pressure field.

Two sealing webs 30.31 or sealing webs 26
, 27, as well as the pressure above the respective high-pressure side control opening, exerts a pressing force on the cylinder block which, together with other measures, causes the cylinder block to move on the high-pressure side. Compensate the force of crimping on the control pin in the area of the control opening.

The details of measures to compensate for these forces are outside the scope of the present invention and will not be described.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a longitudinal sectional view of a radial piston pump, Fig. 2 is an exploded view of a control pin in the radial piston pump shown in Fig. This figure is a cross-sectional view of the control pin taken along the line I-1 in FIG. 1, and FIG. 4 is a diagram showing the relationship between supporting force and static pressure using eccentricity as a parameter. 1... Casing, 2... Casing cover, 3... Hole, 4... Notch, 5
...Control pin, 5'...Ring groove, 6
... Cylinder block, 7 ... Cylinder hole, 8 ... Piston, 9 ... Sliding shoe 10 ... Cam ring, 11.12. ...
... Presser ring, 13 ... Drive shaft, 14 ...
... Ball bearing, 15 ... Shaft seal ring, 1
6... Flange, 17... Clutch disc, 1B, 19... Control opening, 20.21.
...Aisle, 22, 23, 24, 25...
Groove, 26° 27.30, 31... Seal web, 28, 29° 32.33... Support web, 3
4,35...hole, 36.37...horizontal web, 38,39,44°45...web, 4
0~43.46~49...Groove, 50.51...
...Outer line, 52-59...Aisle, 60.
...Aperture section.

Claims (1)

[Claims] 1 A cylinder block containing a piston that performs a stroke movement in a cylinder bore and rotating on a control pin, the control pin having a cylinder block which is diametrically opposed to each other and has an opening in the cylinder bore. Two cooperating control openings are formed, separated from each other by a transverse web, and a groove extending parallel to the control openings and circumferentially of the control pin. , in radial piston machines (pumps or motors) of the type in which a pressure field acts in the area of these grooves, a control opening 18 is provided in each of the aforementioned transverse webs 36, 37, viewed in the circumferential direction of the control pin 5. On both sides of the web 38, 39, 44, 45 are formed two grooves 40-43, 46-49, which extend in the circumferential direction and are located one after the other. grooves 40 to 43, separated from each other by and by one passage 52 to 55, 56 to 59, with respect to the outer circumferential line 50, 51 which intersects the straight line joining the dead center of the piston movement and passes through said transverse web.
, 46-49 located on the same side as the control openings 18, 19
A radial piston machine characterized by being connected to each other.