JPS6047478B2 - compression device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a drive motor and a compressor having an eccentrically guided free piston, in which a cylinder block having a cylindrical piston chamber is rotatably arranged around a fixed axis. and is firmly connected to the rotor of the drive motor, and the eccentric guidance of the piston is carried out by a guide part rotatably arranged with its rotation axis offset from the rotation axis of the cylinder block. and a control slip communicating with the inlet port and the outlet port on the fixed shaft.
The present invention relates to a compression device in which a shaft is provided.

Compression devices of this type are already known, in which a large ball bearing is provided as the guiding part of the piston, the piston is connected to the inner ring of this ball bearing via a roller provided at the end of the piston. Supported. This large ball bearing is arranged eccentrically with respect to the fixed axis in a housing part connected to the housing of the drive motor. Since the fixed shaft and the ball bearing must be precisely fixed to each other in an eccentric position, the housing and housing parts of the motor must be machined with corresponding precision. Furthermore, the large ball bearings required for guiding the piston are relatively expensive. Installing rollers at the piston end is quite expensive. Since this roller has to be subjected to centrifugal forces as well as the forces that occur during the compression of the compressed medium, its support tubes experience considerable wear. The shaft itself, in the case of this known compression device, is held by an intermediate part connectable at one end with the motor casing and in a bore in a casing part connected at the other end with the motor casing. . This structure results in long cumulative errors. The object of the invention is to form the compression device described at the outset in such a way that all parts of the device are fixed to each other in position via only one structural part.

This object, according to the invention, is such that the stator of the drive motor is firmly arranged on the fixed shaft, and the guide part is formed as a pot-shaped casing, which casing is axially connected to said fixed shaft and its This is achieved by being supported on a support shaft pin placed eccentrically with respect to the shaft center.

The fixed shaft thus becomes the central part of the compression device, through which all forces are received and all parts are fixed relative to each other in their position. The guide part and the cylinder block are fixed in eccentric positions with respect to each other via a fixing shaft and a supporting shaft pin connected thereto. The cumulative errors in the arrangement of the parts are thereby reduced to the manufacturing errors of the fixing shaft and the supporting shaft pin. An external rotor type motor was installed as the drive motor. A structural simplification is thus obtained both with respect to the arrangement of the stator and fixed shaft on the rotor and with respect to the support of the rotor.

The present invention will be described in detail below based on embodiments shown in the drawings.

In FIG. 1, 1 is a fixed shaft, and on this fixed shaft 1 is a rotor 4 of a drive motor 5 formed as an external rotor type motor.
is supported by a first ball bearing 2 and a second ball bearing 3.

Stator 4 is connected to cylinder block 6. Second
The ball bearing 35 also supports the cylinder tab 6 at the same time. The cylinder block 6 is formed with a plurality of piston chambers 7 uniformly distributed over its cylinder. Each piston chamber 7 contains one ball 8 as a piston.
is located. Furthermore, in each of the piston chambers 7 there is a support ring 9 for supporting the balls 8 . The inner peripheral surface of the pot-shaped casing 10 forms a guide part for the ball 8. The pot-shaped housing 10 has a supporting sleeve 11 in which two further ball bearings 12 are arranged. Vase-shaped casing 10
is rotatably supported by these ball bearings 12 on a supporting shaft pin 13 connected to the fixed shaft 1. The support shaft pin 13 is connected to the fixed shaft 1 in the axial direction, and its axial center is offset with respect to the axial center of the fixed shaft 1. Furthermore, a stator 14 of a drive motor 5 is fixed on the fixed shaft 1, and a cover ring 15 is placed over the pot-shaped casing 10. In the illustrated embodiment, the portion of the fixed shaft 1 connected to the supporting shaft pin 13 is formed in a conical shape;
This part can also have another rotationally symmetrical shape, for example a cylindrical shape.

An inlet boat 16 and an outlet boat 17 are provided on the support shaft pin 13 and on the conical part of the fixed shaft 1, respectively. A through hole 18 is formed at the bottom of each piston chamber 7 of the cylinder block 6 , which communicates from the bottom of the piston chamber 7 with a control slit provided in the conical portion of the fixed shaft 1 . As can be seen in FIG. 2, two control slits 19, 20 are formed in the conical part of the fixed shaft 1.

In this case, one control slit 19 is connected to the inlet boat 16;
The other control slit 20 is connected to the outlet boat 17. Adjacent to the control slot 19 are a number of holes 21 which can be closed by means of valves (not shown) and which likewise open into the inlet boat 16 . The control slot 20 connected to the outlet boat 17 is divided into a plurality of openings 22, which can likewise be closed via valves (not shown). The individual openings 22 are commonly connected to the outlet boat 17. The entire compression device is built into a sheet metal casing 23.

Since the sheet metal casing 23 does not need to receive any internal pressure from the compression device, the sheet metal casing 23 is not required to have much strength. This casing can therefore be made of lightweight construction. The sheet metal casing 23 is filled with lubricating oil 24 which is sucked in through a slit 25 connected to the inlet boat 16. In order to prevent the lubricating oil 24 from flowing out when the compressor is stopped, a shutoff valve (not shown) is disposed in the slit 25, or a pipe connected to the inlet boat 16 is guided upward in a siphon shape. It's dark. The compression device operates as follows.

That is, the cylinder block 6 is driven by the rotor 4, and the balls 8 disposed in the piston chamber 7 are constantly brought into contact with the inner peripheral surface of the pot-shaped casing 10 due to centrifugal force. Since the pot-shaped casing 10 is arranged eccentrically with respect to the cylinder block 6, the ball 8 moves back and forth within the piston chamber 7. In this case, the medium to be compressed is sucked in by the ball 8 through the inlet boat 16, is subsequently compressed during further rotation of the cylinder block 6, and is discharged again through the outlet boat 17. The pot-shaped casing 10 is entrained by the friction between the ball 8 and the inner circumferential surface of the pot-shaped casing 10.

In reality, only a relative movement due to eccentricity occurs between the ball 8 and the inner peripheral surface of the pot-shaped casing 10. Since the ball 8 can be rotated in all directions, special roller bodies, as in known compression devices, are not required. Due to the Coriolis force and the eccentric arrangement of the cylinder sleeve 6 and the pot-shaped casing 10, a lateral force is generated which generates a correspondingly strong surface pressure between the ball 8 and the side wall of the piston chamber 7. . A support ring 9 is provided to reduce this surface pressure, and the support area of the ball 8 is increased by this support ring 9. This means that the support ring 9 has an inclined part or a rounded part on the side of the ball 8, which makes the support ring 9
This is achieved by projecting into the intermediate chamber between the ball 8 and the wall of the piston chamber 7. Since the support ring 9 is pressed by centrifugal force with its sloped or rounded part into the intermediate chamber, the support ring 9 absorbs the lateral forces of the balls 8 to a large extent. In order to keep the object force small, the ball 8 is preferably made of a light and wear-resistant material, such as alumina sintered ceramic. It is also possible to use hollow spheres. As mentioned above, the conveying capacity of the compression device can be adjusted by extending the control slit 19, which is connected to the inlet boat 16.

For this purpose, holes 21 are provided according to the exemplary embodiment.
If the maximum output of the compression device is not required, one or several holes 21 are opened by means of valves associated with the holes. This allows a portion of the sucked-in medium to be discharged without further compression. The compression process is therefore delayed. Good part-load efficiency of the compression device is thereby achieved. A control slit 20 connected to the outlet boat 17 is connected to a plurality of openings 22 provided with controllable valves.
A uniform discharge pressure of the compression device is obtained by dividing the pressure into two parts.

Each opening 22 with a corresponding discharge pressure is opened by a respective valve. When the medium is sucked through the inlet boat 16, some lubricating oil is also sucked through the slit 25.

The sucked oil is distributed within the piston chamber 7 and into the sphere 8 by centrifugal force. The lubricating oil is also distributed on the wall of the piston chamber 7, thereby sealing the gap between the ball 8 and the wall of the piston chamber 7 and at the same time lubricating this surface. Furthermore, excess lubricating oil is discharged again during compression through the control slit 20 which is connected to the outlet boat 17. In this case, the lubricating oil also enters between the cylinder bushing 6 and the conical part of the fixed shaft 1. The oil also seals the gaps therein and at the same time lubricates the mutually sliding surfaces between the cylinder block 6 and the conical sleeve of the fixed shaft 1.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a compression device based on the present invention, and FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. 1... Fixed shaft, 2, 3... Ball bearing, 4
...Rotor, 5...Drive motor, 6.
...Cylinder block, 7...Zeston chamber,
8... Ball (piston), 9... Support ring, 10... Vase-shaped casing, 511...
...Supporting sleeve, 12...Ball bearing, 13.
...Supporting shaft pin, 14...Stator, 16.
... Entrance boat, 17... Exit boat,
19, 20... control slit, 21, 22...
- Hole.

Claims (1)

[Claims] 1. A compressor consisting of a drive electric motor and a compressor with an eccentrically guided free piston, in which a cylinder block having a cylindrical piston chamber is rotatably arranged on a fixed shaft and the drive The piston is rigidly connected to the rotor of the electric motor, and the piston is eccentrically guided by a guide member which is rotatably arranged with its rotation axis offset from the rotation axis of the cylinder block. In such a compression device in which the fixed shaft is provided with a control slit communicating with the inlet and outlet ports, the stator 14 of the drive motor 5 is rigidly arranged on the fixed shaft 1 and the guide part is provided with a pot-shaped casing. 10, this casing 1
0 is connected to the fixed shaft 1 in the axial direction and is supported on a supporting shaft pin 13 arranged eccentrically with respect to the center of the shaft. 2. Compression device according to claim 1, characterized in that the drive motor is designed as an external rotary motor.