JPS6321384A - Rotary type compressor - Google Patents

Abstract

PURPOSE:To suppress noise without reducing the compression efficiency by installing a plurality of ribs at the positions unequally divided on the periphery of the cylindrical part of a sealed case. CONSTITUTION:A plurality of ribs 24c in the axial direction which project towards the center at the positions unequally divided on the circumference and are continuous to the edge part 24b side close to the center part from the vicinity of the edge part 24a are installed onto the cylinder part 24 of a sealed case 23. A plurality of ribs 24d which project towards the center at the positions unequally divided on the circumference and are continuous to the edge part 24b side close to the center part from the vicinity of the edge part 24b are installed. Therefore, the characteristic frequency due to the deformation of the sectional surface in the axial direction of the sealed case 23 and the deformation of the circular section is shifted to the higher frequency region, and the natural vibration mode in the audio frequency region can be reduced. Further, since the amplitude of the vibration can be reduced, noise can be reduced without reducing the compression efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a rotary compressor used in a freezing and refrigeration system.

BACKGROUND OF THE INVENTION In recent years, compressors used in refrigeration systems have been shifting from reciprocating type to rotating type from the viewpoint of energy and space saving. These rotary compressors are typically
The electric compression element is fixed to the closed case by shrink fitting or welding the electric motor stator and bearing or cylinder. Therefore, the vibrations generated by the electric compression element are transmitted to the sealed case without being absorbed by the spring or the like, which may cause the sealed case to vibrate and generate large noise.

An example of the conventional rotary compressor mentioned above will be described below with reference to the drawings.

FIG. 4 shows an example of a conventional rotary compressor.

In the figure, 1 is a rotary compressor.

2 is an electric motor, 3 is a stator, 4 is a rotor, and 5 is a winding of the stator. 6 is a compression element, 7 is a crankshaft fixed to the rotor 4, 8 and 9 are bearings that support the crankshaft 7, 10 is a cylinder, and 11 is a piston that is slidable around the crank portion 7a of the crankshaft. .

12 is a discharge cover, and 14 is an oil supply pipe that includes a spring 13 connected to the crankshaft 7. 15 is a sealed case made of a rigid material with a thickness of 2.5 mm for internally fixing the stator 3 and the bearing 8. It consists of a cylindrical part 16 and a cup-shaped lid part 17, 1B with a thickness of 3 mm. 19 is a suction pipe, 20 is a discharge pipe, and 21 is refrigerating machine oil.

The operation of the rotary compressor configured as above will be described below.

Mainly, refrigerant pressure pulsations and mechanical vibrations caused by compression of the refrigerant in the cylinder 1o vibrate each component, propagate through the bearing 8 or the refrigerant in the closed case 14, and are transmitted to the closed case 14. Therefore, the sealed case 15 vibrates and generates noise.

Problems to be Solved by the Invention The sealed case 15 exhibits rigid vibration without deformation in the frequency range from IK)h to 2Kl-h, but undergoes elastic vibration accompanied by deformation in the frequency range higher than that. do.

The sealed case 16 includes the stator 3 and the bearing 10 in the cylindrical portion 16.
is internally fixed, elastic vibration accompanied by deformation of the circular cross section of the sealed case 16 occurs in the high frequency range of 5KI-h or more, and in the frequency range of 2 to 5KI42, the vibration is shown in Fig. 6. The main component is elastic vibration accompanied by axial deformation.

In addition, in FIG. 6, A shows an undeformed shape, and B shows a deformed shape.

Therefore, between 2 and 6x+h, vibrations occur mainly due to deformation of the axial cross section of the sealed case, and at 6KI4 and above, noise is generated due to vibrations accompanied by deformation of the circular cross section of the sealed case.

In view of the above-mentioned problems, the present invention provides an extremely effective compressor noise reduction effect without reducing compressor efficiency and without substantially impairing the compactness of the compressor.

Means for Solving the Problems In order to solve the above problems, the rotary compressor of the present invention has the following features:
The cylindrical part of the sealed case has multiple lips in the axial direction that protrude toward the center at positions that divide the circumference unevenly and extend from the vicinity of one end to the other end from the center, and a circular shape that does not overlap with these lips. It is provided with a plurality of lips in the axial direction that protrude toward the center at positions that divide the circumference unevenly and extend from near the other end to the one end from the center.

Function The present invention aims at reducing noise in the audible frequency range by shifting vibrations accompanied by deformation of the axial cross-section of the sealed case and vibrations accompanied by deformation of the circular cross-section to a high frequency range, using the above-described configuration. .

EXAMPLE Hereinafter, a rotary compressor according to an example of the present invention will be described with reference to the drawings. In addition, to avoid duplication of explanation,
The same parts as in the conventional example are given the same reference numerals, and the explanation will be omitted.

1 to 3 show an embodiment of a rotary compressor of the present invention. In the figure, 22 is a stator with a cylindrical outer circumference, 23 is a sealed case made of rigid material, 24 is a cylindrical portion with a thickness of 2.5 mm, and 25° 26 is a 3M thick! + It is a cup-shaped lid part.

The cylindrical portion 24 is provided with four lips 24c that protrude toward the center at positions that divide the circumference unevenly and extend from near one end 24a to the other end 24b from the center. . These ropes 24c are arranged so as to divide the cylindrical portion 24 unevenly in the circumferential direction at a ratio of 6:4:6:3.

Further, the cylindrical portion 24 is provided with four lips 24d that protrude toward the center at positions that unevenly divide the circumference and extend from the vicinity of the end portion 24b to the end portion 24a side from the center portion.

These lips 24d divide the cylindrical portion 24 unevenly in the circumferential direction at a ratio of 6:4:5:3, as opposed to the lips 24c, and are arranged so as not to overlap with the lips 24c.

The operation of the rotary compressor configured as above will be explained below.

Mainly, refrigerant pressure pulsations and mechanical vibrations caused by compression of the refrigerant in the cylinder 1o vibrate each component and propagate through the bearing 8 or the refrigerant in the closed case 23, and are transmitted to the closed case 23. Therefore, the sealed case 23 vibrates and generates noise.

The sealed case 23 performs rigid vibration without deformation in a frequency range of 1 to 2KI+, but performs elastic vibration with deformation in a frequency range higher than that.

The sealed case 23 has the stator 22 and the bearing 1 in the cylindrical part 24.
Since 0 is internally fixed, elastic vibrations are mainly due to deformation in the axial direction at low frequencies, and as the frequency increases, deformations in the circular cross section appear. However, since the cylindrical portion 24 is provided with ribs 24C and 24d in the axial direction, the sealing case 23 has greater rigidity against deformation in the axial cross section. The natural frequency due to cross-sectional deformation increases.

Furthermore, since the ribs 24C and 24d are arranged so as to divide the circumference unevenly, vibrations due to deformation of the circular cross section cannot take a perfectly axially symmetrical mode, so the natural frequency becomes high.

Furthermore, since the ribs 24c and 24d are arranged so that their circumferential cross sections are divided into different sections without overlapping each other, the vibrations caused by the circular cross-sectional deformation on the end 24a side and the end 24b side are transmitted to the other end. It is difficult to excite vibration due to the circular cross-sectional deformation on the portions 24b and 24a sides, and a damping effect is exerted, so that the amplitude of the circular cross-sectional deformation is extremely small for the same excitation force.

Furthermore, even if the outer peripheral shape of the stator 22 is circular,
The ribs 24d ensure a flow path for refrigerating machine oil and refrigerant, so there is no need to provide a cutout in the stator 22 for the flow of refrigerating machine oil and refrigerant, unlike in the past.In addition to improving motor efficiency, it is possible to The cross-sectional area of the flow path can be widened, and the motor can be cooled effectively.

As described above, according to this embodiment, the cylindrical portion 24 of the sealed case 23 has protrusions extending toward the center at positions that divide the circumference unevenly, and from near the end 24a to the other end 24b from the center. A plurality of continuous axial ribs 24G and these ribs 2
40 and protrudes toward the center at a position that divides the circumference unevenly, from near the end 24b to the center from the end 24a.
By providing a plurality of ribs 24d in the axial direction connected to the side, it is possible to shift the natural frequency due to deformation of the axial cross section and circular cross section of the sealed case 23 to a high frequency region, and reduce the natural vibration mode in the audible frequency region. Moreover, the damping effect can reduce the vibration amplitude caused by the deformation of the circular cross section, and the compressor efficiency can be improved by improving the motor efficiency, and the compressor reliability can be improved by improving the motor cooling. Compressor noise can be reduced.

Effects of the Invention As described above, the present invention provides a rotary compressor in which an electric compression element is housed in a sealed case. A plurality of ribs extending in the axial direction from the vicinity of the center to the other end, and protruding toward the center at positions that do not overlap with these ribs and divide the circumference unevenly from the vicinity of the other end to the center from the center. By providing multiple axial ribs connected to one end, the natural frequency due to the deformation of the axial cross section of the sealed case and the deformation of the circular cross section is shifted to a higher frequency range, thereby reducing the natural vibration mode in the audible frequency range. In addition, the damping effect can reduce the amplitude of vibration caused by the deformation of the circular cross section.Furthermore, the compressor efficiency can be improved by improving the motor efficiency, and the reliability of the compressor can be improved by improving motor cooling. This improves the performance of the compressor and stably reduces compressor noise.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a cylindrical part of a sealed case of a rotary compressor showing an embodiment of the present invention, Fig. 2 is a sectional view of Fig. 1, and Fig. 3 is a sectional view of Fig.
4 is a sectional view of a conventional rotary compressor, and FIG. 6 is a diagram showing natural vibration modes due to deformation of the axial cross section of the closed case of the same compressor. 22... Stator, 23... Sealed case, 24... Cylindrical portion, 24c... Rib, 2
4d...Rib. Name of agent: Patent attorney Toshio Nakao and one other person

Claims (1)

[Claims] Both ends are circular, and there are multiple ribs in the axial direction that protrude toward the center at positions that divide the circumference unevenly and extend from near one end to the other end, and these ribs do not overlap. A sealed case comprising a substantially cylindrical portion and a cup-shaped lid portion having a plurality of ribs in the axial direction protruding toward the center at positions that unevenly divide the circumference and extending from near the other end to the central portion toward the one end. A rotary compressor with an electric compression element that is housed within this closed case.