JPH0115714B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary compressor used in refrigeration equipment, etc., and by shifting the phase of the discharge stroke in two discharge holes to reduce the composite component of discharge pressure fluctuation with respect to the piston. The purpose of this invention is to reduce the size and vibration of the motor by reducing the torque load and torque fluctuation of the motor, and to improve efficiency by reducing losses due to pressure pulsations in the discharge pipe system.

As shown in Fig. 4, in the conventional rotary compressor a, each discharge hole b, c is arranged symmetrically with respect to the rotation axis d, so that the compressed working fluid is discharged from each discharge hole b, c. are carried out in the same phase, and since the piston e is also axially symmetrical with respect to the rotational axis d, the fluctuating pressures in the compression chambers f and g relative to the piston e are added, as shown in FIG. Therefore, the pressure variation with respect to the piston e is doubled. Therefore, the torque load and torque fluctuation of the motor become large, and the pressure pulsations in the discharge pipe system also tend to increase, causing problems in terms of pipe vibration and strength.

In view of the above-mentioned drawbacks, the present invention changes the vane position by
By shifting the axial symmetry and shifting the discharge phase of the compressed working fluid, pressure fluctuations against the piston are reduced.

An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 3.

1 is a sealed case that houses the electric compression element 2;
3 is a motor element, and 4 is a compression element. 5 is a circular piston with a smooth curve and two tops 5a arranged at equal positions; 6 is a shaft to which the piston 5 is fixed, and is connected to the motor element 4; This shaft 6 is rotatably mounted by an upper bearing 8 and a lower bearing 9 fixedly disposed at the upper and lower parts of a cylinder 7 having a circular cross section. Furthermore, the piston 5 located within the cylinder 7 is concentric with the shaft 6, and rotates while maintaining a constant gap from the circumferential surface of the cylinder 7 at each top 5a of the piston 5. 2 vanes 10,
The tip of the cylinder 11 is slidably inserted into grooves 7a and 7b provided in the cylinder 7 so as to come into contact with the piston 5 by a spring 12 installed at the rear.
The vane 11 is arranged at a position advanced by 30 degrees in the rotational direction from a position symmetrical to the vane 10 with respect to the rotation axis. The discharge holes 13, 14 and the suction holes 15, 16 are installed close to both sides of each vane 10, 11, respectively.

In such a groove configuration, the piston 5 is connected to the shaft 6
When rotated by the electric motor element 3 via
7b is divided into suction chambers 18a and 18b to perform compression work. At this time, since the vane 11 is provided at a position advanced by 30 degrees in the rotational direction from a position symmetrical to the vane 10 with respect to the rotation axis, as shown in FIG. Phase shift of peak of fluctuating pressure, compression chambers 17a, 1
When the pressure of either one of the pistons 7b is rapidly decreasing, the pressure of the other is rapidly increasing, so that the peak of the resultant fluctuating pressure on the piston 5 is significantly reduced compared to the conventional example. Therefore, the torque load and torque fluctuation of the motor are reduced, and the pressure pulsations in the discharge piping system are also reduced, so it is possible to improve efficiency by downsizing the motor, reducing vibration in the rotational direction, and reducing loss in the discharge piping system. Can be done.

As described above, the present invention provides a cylinder with a non-circular cross section, which is provided with a cylinder having a circular cross section, and two apexes evenly distributed on the outer circumferential surface, and arranged such that these apexes have a certain gap from the cylinder. A piston, and at least two vanes that are slidably provided in a part of the cylinder and whose tips are pressed against the piston by a spring, and the vanes are arranged unevenly in the cylinder,
By shifting the phase of the peak of the fluctuating pressure in the compression chamber partitioned between each vane, the peak value of the composite fluctuating pressure can be reduced compared to conventional methods, making the motor more compact, reducing vibration, and improving efficiency. It is something.

[Brief explanation of drawings]

FIG. 1 is a central sectional view of a main part showing an embodiment of the present invention, FIG. 2 is a sectional view taken along the line -' in FIG. 1,
Fig. 3 is a diagram showing the pressure fluctuation of the compressed working fluid in an embodiment of the present invention, Fig. 4 is a sectional view of the compression section showing the conventional example, and Fig. 5 is a diagram showing the pressure fluctuation of the compressed working fluid in the conventional example. It is a diagram. 5... Piston, 7... Cylinder, 5a... Top, 10, 11... Vane.

Claims (1)

[Claims] 1. A cylinder with a circular cross section, a piston with a non-circular cross section, which is provided with two peaks evenly distributed on the outer circumferential surface and arranged such that these peaks have a certain gap with the cylinder, and one of the cylinders. a rotary compressor, comprising at least two vanes that are slidably disposed in a section and whose tips are pressed against the piston by a spring, and in which the vanes are arranged offset from symmetrical positions with respect to a rotation axis.