JPS6056196A - Rotary compressor - Google Patents

Abstract

PURPOSE:To reduce the size of compressor while to prevent resonance of muffler, by providing an expansion type muffler in the bearing at the end of crank shaft of rotary compressor and eliminating an independent muffler. CONSTITUTION:A recess 12 for mounting a deliver valve 12a and a grooved recess 14 having approximately uniform cross-section are provided in the counter- cylinder face 11a of the shaft 11 at the crank shaft end side of bearings applied on both sides of cylinder where they 12, 14 are comunicated through a small groove 13 while the counter-cylinder face 11a is covered with a partitioner 15 and separated from the delivery chamber 10 and the recess 14 will constitute the expansion chamber 14b of muffler. In order to achieve similar effect as inserting a tail tube, a hole 16 is made approximately in the center of the recess 14. Refrigerant is delivered through the small groove 13 into the expansion chamber 14b and muffled then delivered through a hole 16 into the delivery chamber 10.

Description

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

Conventional Structure and Problems Rotary compressors used in freezing and refrigerating systems generate large noises due to pressure pulsations of refrigerant compressed within the cylinder. For this reason, conventional methods have been used to reduce noise by attaching a muffling device to the refrigerant flow path inside the sealed case, but the provision of the muffling device has made it difficult to downsize the compressor. In addition, there was a problem in that the installed muffler caused resonance and generated further noise. A conventional configuration will be explained with reference to FIG.

In the figure, 1 is a rotary compressor, 2 is a closed case, and 3 is a rotary compressor.
is fixed to the sealed case 2 by a stator through a shrink fit. 4
is a rotor connected to the crankshaft 6. 6
is a piston, and 7 is a cylinder. 8 is a bearing on the rotor side, which is fixed to the sealed case 2 by welding. 9 is a bearing at the end of the shaft, 1Q is a discharge chamber, which is constructed by fixing a cup-shaped discharge cover 10a to the bearing 9, and 10' has one end communicated with the discharge chamber 10 and the other end sealed. This is a silencer opened inside the case 2.

In this configuration, the refrigerant gas compressed within the cylinder 7 is discharged into the sealed case 2 through the discharge chamber 1Q, the muffler 10' and the silencer 10'. Therefore, the pressure pulsations of the refrigerant generated in the discharge chamber 10 in the cylinder γ are reduced in the muffler 10', and the pressure pulsations in the shell are reduced, thereby reducing noise. However, this method requires a space for installing the silencer 10', which not only hinders the miniaturization of the compressor 1, but also causes the problem that the silencer causes resonance and generates abnormal noise. Ta.

OBJECTS OF THE INVENTION It is an object of the present invention to compactly provide an expansion type muffler on a bearing in order to downsize a compressor, and to prevent resonance in the amount of muffling caused by providing a separate muffler.

Structure of the Invention In order to achieve this object, the present invention includes a recess for installing pulp on the opposite cylinder surface of the bearing, and a groove-like recess having a substantially uniform cross-sectional shape for an expansion chamber, one end of which communicates with the recess through a small groove. By interposing a partition plate having a hole corresponding to approximately the center of the groove-shaped recess between the bearing and the discharge chamber, an expansion type muffler is constructed, and the noise of the compressor is reduced. The aim is to

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. 2 to 8. In order 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.

11 is a bearing that supports the crankshaft 6; the bearing 11
The anti-cylinder surface 11a is provided with a groove-shaped recess 14 having a substantially uniform cross section and communicating with the cylinder recess 12 through a recess 12 and a small groove 13 for mounting the pulp 12a. Note that the groove-shaped recess 14 communicates with the recess 12 via the small groove 13 at its end 14a. Further, 12b is a pulp hole.

Reference numeral 15 denotes a partition plate interposed between the bearing 11 and the discharge chamber 1Q, and the partition plate 16 separates these recesses 12. The groove-shaped recess 14 and the small groove 13 are separated from the discharge chamber 10. The concave portion 12, the groove-shaped concave portion 14, and the small groove 13 are a small passage 13a that communicates the valve chamber 12a, the expansion chamber 14b, and the pulp chamber 12C with the expansion chamber 14b, respectively.
form. Further, in the partition plate 16, there are holes 16 that communicate the expansion chamber 14b and the discharge chamber 10 at positions corresponding to the vicinity of the center portion 14d between the end portion 14a that communicates with the small groove 13 of the groove-like recessed portion 14 and the opposite end portion 14C. is provided.

In this configuration, the refrigerant compressed within the cylinder γ is discharged from the pulp hole 12b into the pulp chamber 12c formed by the recess 12 and the partition plate 15.

Further, the refrigerant is ejected through the small passage 13a formed by the small groove 13 and the partition plate 16, into the expansion chamber 14b formed by the groove-like recess 14 and the partition plate 16, and then into the discharge chamber 1 through the hole 16.
0 and is discharged from the discharge chamber 10 into the sealed case 2. In this way, the refrigerant compressed within the cylinder 7 passes through the expansion chamber 14b before being discharged into the sealed case 2 via the discharge chamber 10. Therefore, the pressure pulsation component of the refrigerant generated in the cylinder 7 and in the pulp 12a is attenuated by the expansion type silencing effect when the refrigerant passes through the expansion chamber 14b, so the pressure pulsation of the refrigerant radiated into the sealed case 2 is reduced and compressor noise is reduced.

As shown in FIG. 8, the hole 16 provided in the partition plate 16 is
The end 14a communicating with the small groove 13 of No. 4 and the opposite end 14C
The damping characteristics of pressure pulsation are shown in the case where the pressure pulsation is provided near the center portion 14d and the case where the pressure pulsation is provided near the end portion 140. From FIG. 8, it can be seen that when the hole 16 is provided at approximately the center portion 14d, the amount of attenuation of pressure pulsation is significantly greater than when it is provided at the end portion 14c.

This has a hole 1 at a position corresponding to the center of the groove-like recess 14.
This is because, by providing a substantially cylindrical expansion type muffler, the pressure pulsation damping effect almost the same as that obtained when a tail pipe is inserted can be obtained.

In this way, by making the hole 16 that communicates the expansion chamber 14b with the discharge chamber 10 correspond to the groove-like recess, the effect of damping pressure pulsations is extremely effective, and the effect of reducing compressor noise is also large.

Furthermore, by using the bearing 11 and simply adding the partition plate 14, an expansion-type noise reduction effect can be obtained.

In addition to reducing the size of the compressor, it is also possible to prevent accidents caused by abnormal noise caused by resonance of a separate silencer.

Effects of the Invention As described above, the present invention has a rotary compressor that houses an electric compression element in a sealed case, and has a recess for mounting a valve formed on the opposite side of the cylinder, and a small groove formed at one end of the recess. A bearing having a groove-like concave portion having a substantially uniform cross-sectional shape for an expansion chamber that communicates through the bearing, a discharge chamber disposed on the side having the groove-like concave portion, and interposed between the bearing and the discharge chamber.

In addition, by providing a partition plate having a hole corresponding to the approximate center of the groove-like recessed part, it is possible to attenuate pressure pulsation components generated in the cylinder or in the pulp released into the sealed case. , and it is possible to reduce noise without increasing the size of the compressor.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a rotary compressor showing a conventional example, Fig. 2 is a cross-sectional view of a rotary compressor showing an embodiment of the present invention, and Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2. Figure 4 is the same (B
- A sectional view taken along line B, and FIG. 6 are the same (a sectional view taken along line C-C, and FIG. 6 is a sectional view taken along line D-D in FIG. 5,
Figure 7 is a perspective view of the bearing, partition plate, and discharge cover, and Figure 8 shows the sound pressure attenuation characteristics when the holes in the partition plate are provided in the center and at the ends of the groove-shaped recess. It is a diagram. 2... Sealed case, 12... Concavity, 1
3...Small groove, 14...Concave portion, 11.
...Bearing, 10 ...Discharge chamber, 1
6...hole, 16...partition plate. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 4 14η Figure 6 Figure 1 Figure 7 Figure 8 tK 2K at t, s; Frequency of rotation at t, 5 (Hz)

Claims (1)

[Claims] A sealed case housing an electric compression element, a recess for installing a valve formed on the opposite side of the cylinder, and a groove-shaped recess having a substantially uniform cross-sectional shape for an expansion chamber whose four parts and one end communicate with each other via a small groove. a bearing having a bearing, a discharge chamber disposed on the side having the concave portion, and a partition plate interposed between the bearing and the discharge chamber and having a hole corresponding to a substantially central portion of the groove-like concave portion. A rotary compressor equipped with