JPS58217791A - Rotary compressor - Google Patents

Abstract

PURPOSE:To reduce the size of a motor and to increase the efficiency of the same, by disposing vanes unsymmetrically in a cylinder, shifting the phases at which the peak value of varying pressure in compression chamber divided by the vanes take place, and thereby lowering the peak value of the composite varying pressure. CONSTITUTION:A vane 11 is disposed at a position advanced 30 deg. in the direction of rotation from the position symmetrical to a vane 10 with respect to a turning shaft 6, so that the phases at which the peak values of varying pressure of work fluid in compression chambers 17a, 17b are deviated. That is, since pressure in one compression chamber is increased rapidly when pressure in the other compression chamber is rapidly lowered, the peak value of the composite varying pressure acted to a piston 5 is lowered extremely as compared with that of the conventional arrangements. Thus, since the torque load and the torque fluctuation of a motor are reduced and pulsation of pressure in the exhaust piping system is also reduced, it is enabled to reduce the size of the motor, to reduce vibration in the direction of rotation of the motor and to raise the efficiency by reducing the fluid loss in the exhaust piping system.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary compressor used in refrigeration equipment, etc.
By shifting the phase of the discharge stroke in each discharge hole and reducing the composite component of discharge pressure fluctuations for the piston, the motor can be made smaller and vibrations can be reduced by reducing the motor torque load and torque fluctuation, and the discharge pipe The objective is to improve efficiency by reducing losses due to pressure pulsations in the system.

As shown in Fig. 4, in a conventional rotary compressor a, each discharge hole is
Since c is arranged symmetrically with respect to the rotation axis d, the compressed working fluid is discharged from each discharge hole c in the same phase, and the piston e is also axially symmetrical with respect to the rotation axis d. Therefore, as shown in FIG. 5, the pressure fluctuations in the compression chambers f and g relative to the piston e are added, so that the pressure fluctuation relative 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 aims to reduce pressure fluctuations against the piston by shifting the vane position from axial symmetry and shifting the discharge phase of the compressed working fluid.

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

Reference numeral 1 designates a closed case that houses an electric compression element 2, 3 a motor element, and 4 a compression element. 5 is a circular piston with a straight 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 electric motor element 4; has been done. 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 70 at each top 5a of the piston 5. The tips of the two vanes 10 and 11 are slidably installed in a groove 7a provided in the cylinder 7 so that they come into contact with the piston 5 by means of a spring 12 installed at the rear. 10 and is arranged at a position 30 degrees further in the rotational direction than the symmetrical position with respect to the rotation axis. Discharge hole 13.14 and suction hole 15.1
6 are each located close to each side of each bay 710.11.

In this configuration, when the piston 5 is rotated by the electric motor element 3 via the shaft 6, the space overlapped by the inner circumferential surface of the cylinder 7 and the outer circumferential surface of the piston 5 becomes the vane 10,1.
1 allows the compression chamber to open.

It is divided into suction chamber 17b and suction chambers 18a and 18b to perform compression work. At this time, since the vane 11 is provided at a position 3o0 forward in the rotation direction from a position symmetrical to the vane 10 with respect to the rotation axis, each compression chamber 17a,
The peak of the fluctuating pressure of the compressed working fluid in 17b is out of phase in the compression chamber 17d.

When the pressure of either one of the pistons 17b is rapidly decreasing, the pressure of the other is rapidly increasing, so 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 fluctuations on the motor are reduced, and the pressure pulsations in the discharge piping system are also reduced, making it possible to improve efficiency by downsizing the motor, reducing vibration in the direction of rotation, and reducing losses in the discharge piping system. can.

As described above, the present invention provides a cylinder having a circular cross section,
A piston with a non-circular cross section, which is provided with two apexes evenly distributed on the outer circumferential surface and arranged such that these apexes have a constant gap between the cylinders, is slidable on a part of the cylinder. At least two vanes are provided in the cylinder, the tips of which are pressed against the piston by a spring, and by arranging the vanes unevenly within the cylinder, fluctuation pressure in the compression chamber partitioned between each vane can be reduced. By shifting the phase of the peak, the peak value of the composite fluctuating pressure can be reduced compared to the conventional method.
This makes it possible to reduce the size of the motor, reduce vibration, and improve efficiency.

[Brief explanation of drawings]

FIG. 1 is a central sectional view of the main part showing one embodiment of the present invention, and FIG.
The figure is a sectional view taken along the line II-I' in FIG. 1, FIG. 3 is a diagram showing pressure fluctuations of the compression working fluid in an embodiment of the present invention, and FIG. 4 is a sectional view of the compression section showing a conventional example. FIG. 5 is a diagram showing pressure fluctuations of compressed working fluid in a conventional example. 5----...Piston, 7...e...0 cylinder, 5
a...-Top, 10, 11...Yutaka 6φ vane. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Fig. 2 Gui Fig. 3 Bis [So @ East (different (°) Fig. 4 Section 5)

Claims (1)

[Claims] A cylinder having a circular cross section, a non-circularly cut piston having two tops evenly distributed on the outer circumferential surface and arranged such that these tops have a certain gap with the cylinder, and one of the cylinders. A rotary compressor, comprising at least two vanes that are slidably disposed on a portion of the rotor and whose tips are pressed against the piston by a spring, and the vanes are arranged offset from symmetrical positions.