JPH08270585A - Silencer mechanism of rotary compressor - Google Patents

Abstract

PURPOSE: To prevent the occurrence of up and down vibration of a rotor by putting the gas passage groove on the periphery of a stator, a through hole, or the gas passage hole of a rotor each in helical form having a tilt angle of lead, and setting the length an integer times as large as the length of pulsatory wave of frequency thereby synchronizing the phases of the phases of upper and under pulsations of the stator. CONSTITUTION: In a compressor, an electromotive element 24 consisting of a stator 22 and a rotor 3, on the upper side of a sealed container, and a rotary compressive element 7 including a discharge valve 5 and a cylinder 6, on the under side, and accommodated. In this case, a gas passage groove 22, which has a rectangular section, is made in helical form, which advances at an angle of θ, along the stator 22. The angle θ is set so that the length 1.1/sinθ may be an integer times as large as the length of the pulsation of frequency, and the angle θ is found out from the expression 1.1/sinθ=n.C/2(f-α). Among the expression, 1 is the lamination [m] of a stator 22 or a rotor 3, and n is an integer, and C is sound velocity [m/s] in a refrigerant, and f is the frequency [Hz] of power, and α is slip frequency [Hz].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary compressor for air conditioning and freezing, and more particularly to a sound deadening mechanism for this rotary compressor.

[0002]

2. Description of the Related Art A vertical sectional view of a conventional air-conditioning and refrigerating rotary compressor is shown in FIG. 9 and its structure is outlined.

The rotary compressor includes a rotary compression element 7 including an electric element 4 composed of a stator 2 and a rotor 3 on an upper side of a closed container 1 and a discharge valve 5 and a cylinder 6 on a lower side thereof.
To store. Refrigerant gas from the receiver tank 8 is at the inlet 9
From the valve 5, is discharged from the valve 5 and passes through the outer circumference of the stator 2 as indicated by an arrow A1, and a part of the stator 2 and the rotor 3 pass as indicated by an arrow A2. It is sent out from the exit 10. 11 is a shaft.

FIG. 10B is a graph showing the pulsation of the discharge gas in the lower portion of the stator shown in FIG. 9, and the pulsation of the discharge gas from the discharge valve 5 in the above structure is shown in FIG.
As shown in (B), it occurs at a frequency twice the rotational frequency of the rotor.

On the other hand, FIG. 10A is a graph showing the pulsation of the discharge gas in the upper part of the stator shown in FIG. 9, and in the upper part of the stator 2, the length 1 of the product thickness of the stator which is the propagation passage length of the discharge gas. The phase is delayed by an amount corresponding to
(B) Phase lag D) Since the pulsation occurs at the same frequency as the lower part of the stator, a pressure difference above and below the stator also occurs as pulsation.

[0006]

The pressure difference between the upper and lower portions of the stator is the pressure difference of the average pressure plus the above pulsating component. This pressure difference causes the rotor to pulsate up and down, resulting in thrust noise of the shaft 11. Often occurs. The thrust force acting system can be expressed by the following simple formula.

Shaft thrust force (pressing force) = W + FS−S × ΔP (Formula 1) where W: rotor and shaft weight (downward) FS: thrust force due to rotor skew (downward) S: rotor Vertical pressure difference effective working area ΔP: Rotor vertical pressure difference.

The thrust force of (Equation 1) above is always (+)
If so, the vertical vibration of the rotor does not occur, but the vertical pressure difference ΔP of the rotor is a pulsating component as described above, and the thrust force may be (−).

There has been a demand for reducing ΔP so that the thrust force of (Equation 1) is always (+) and preventing the generation of shaft thrust noise.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention sets the gas passage lengths of a stator and a rotor as follows.
By providing the gas passage groove on the outer periphery of the stator, the through hole, and the forward inclination angle θ in the gas passage hole of the rotor,
A rotary compressor that is set to an integral multiple of the frequency pulsation wavelength that is twice the rotation frequency, synchronizes the phase of the pulsation above and below the stator, cancels the increase in pressure difference due to pulsation, and prevents rotor vertical vibration. It is intended to provide a sound deadening mechanism.

[0011]

The method of obtaining the angle .theta. Will be described with reference to FIGS.

Since the basic component of the discharge pulsation is twice the rotation frequency, the discharge pulsation frequency = 2 (f-α) (Equation 2) where f: power supply frequency [Hz] α: slip frequency [ Hz].

Further, if the gas passage propagation length of the electric element is L, then L = 1 / sin / sin θ (Equation 3) where: l: stator or rotor product thickness [m] θ: stator An angle [rad] of the outer gas passage groove and the rotor gas passage hole, where L is an integral multiple of the discharge pulsation wavelength, (Equation 2)
And from (Equation 3), l · 1 / sin θ = n · C / 2 (f−α) (Equation 4) where n: integer C: sound velocity [m / s] in the refrigerant, The groove angle θ is given by (Equation 4).

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a silencing mechanism for a rotary compressor according to the present invention will be described below with reference to the drawings. First Embodiment: FIG. 1 is a longitudinal sectional view of a first embodiment of a rotary compressor having a sound deadening mechanism, and FIG. 2 is a sectional plan view of FIG.

1 and 2, the same parts as those in FIG. 9 are designated by the same reference numerals, and only different points will be described.

In the first embodiment, the gas passage groove 2 having a rectangular cross section along the outer circumference of the stator 22 of the electric element 24.
Two windings 2a are provided symmetrically with respect to the central axis of the rotary compressor in a spiral shape that advances at an angle θ. This angle θ is obtained from the above (formula 4). Second Embodiment: FIG. 3 is a perspective explanatory view of a rotor and a stator portion of the second embodiment.

In the second embodiment, the gas passage hole 23 having a circular cross section in the rotor 23 at four equally divided positions in the circumferential direction.
a is provided. In this case, 1 is the product thickness of the rotor.

FIG. 4 (A) is a graph showing the pressure pulsation curve of the upper stator according to the first and second embodiments, and FIG. 4 (B) is a graph showing the pressure pulsation curve of the lower stator according to the first and second embodiments. Since the gas passage groove or the through hole is provided, the pressure pulsation has the same phase as shown in FIG. 4, and the pressure difference due to the pulsation becomes almost zero. Third Embodiment: FIG. 5A is a plan view of the lower valve side of the third embodiment, and FIG. 5B is a plan view of the upper valve side of the third embodiment.

In the case of the upper and lower valve type rotary compressors (the same applies to the two cylinder type rotary compressor), conventionally, although not shown, the gas discharged from the lower valve of the cylinder is directly discharged into the closed container, or A gas passage was provided asymmetrically in the valve cover of the upper valve at the position of the valve. Therefore, even if the valve cover holes are symmetrical at a position of ± 90 ° with respect to the valve, the two valve cover holes do not become symmetrical sound sources with respect to the space inside the closed container.
A standing wave in the circumferential direction is excited in the space.

With respect to this problem, the third embodiment is
Referring to FIG. 5, the gas discharged from the lower valve 35a is once discharged through the lower valve cover 37a and the cylinder gas passage 33 into the upper valve cover 37b. The cylinder gas passages 33 are provided at symmetrical positions. Also, the upper valve cover hole 34
Is the upper valve 35b and the gas passage 33,
It is installed at the 90 ° position. As a result, the gas pressure pulsation discharged from the upper valve 35b and the gas passage 3
Even if the power and phase of the pressure pulsation of the gas discharged from 3 are different, the pulsation of gas discharge from the two symmetrical valve cover holes 34 is symmetrical, and this valve cover hole 34 is in relation to the space inside the closed container. Can be regarded as a symmetrical sound source. The standing wave (cavity resonance) generated in the circumferential direction of the space is
Since they are interfered by the individual symmetrical sound sources, it is possible to significantly reduce the cavity resonance generated in the circumferential direction, that is, the noise of the first, second, ...

FIG. 6 shows the microphone position in the cylinder gas passage 33.
The graph of the data measured by is shown. The shaded area R in FIG. 6 is the noise reduction area according to the third embodiment. Fourth Embodiment: FIG. 7 is a sectional view of a rotary compressor according to a fourth embodiment, and the same parts as those in FIG. 9 are designated by the same reference numerals.

FIG. 8 is an enlarged view of the lower bearing portion of FIG.

In the fourth embodiment, the bush 44 is inserted into the lower bearing 42 so that it is pressed by the lower muffler 43. The upper and lower thrust portions of the shaft 11 and the corresponding upper and lower bearings. The gap between the thrust portions 41 and 42 is minimized to suppress the vertical movement of the shaft 11, thereby suppressing the generation of abnormal noise.

[0024]

Since the sound deadening mechanism of the rotary compressor of the first and second embodiments of the present invention is constructed as described above, the vertical vibration of the rotor and the shaft is prevented from occurring and the sound is sealed. By significantly reducing the cavity resonance generated in the circumferential direction in the container, noise reduction and improvement of the durability of the rotary compressor are achieved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a first embodiment of a rotary compressor including a sound deadening mechanism according to the present invention.

FIG. 2 is a cross-sectional plan view of FIG.

FIG. 3 is a perspective explanatory view of a rotor and a stator portion of a second embodiment.

4A is a graph showing a pressure pulsation curve of a stator upper portion according to the first and second embodiments, and FIG. 4B is a graph showing a pressure pulsation curve of a stator lower portion according to the first and second embodiments.

FIG. 5A is a plan view of the lower valve side of the third embodiment,
(B) is a plan view of the upper valve side of the third embodiment.

FIG. 6 is a graph of measurement data showing a noise reduction area according to the third embodiment.

FIG. 7 is a sectional view of a rotary compressor according to a fourth embodiment.

FIG. 8 is an enlarged view of the lower bearing portion of FIG.

FIG. 9 is a vertical sectional view of a conventional rotary compressor.

10A is a graph showing discharge gas pulsation in the upper portion of the stator shown in FIG. 9, and FIG. 10B is a graph showing discharge gas pulsation in the lower portion of the stator shown in FIG.

[Explanation of symbols]

 1: Sealed container 2: Stator 3: Rotor 4: Electric element 5: Discharge valve 6: Cylinder 7: Rotary compression element 22: Stator 22a: Gas passage groove 23: Rotor 23a: Gas passage hole 24: Electric element

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hitomi Takagi 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Denki Co., Ltd. (72) Inventor Akira Hashimoto 2-chome, Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1. In a rotary compressor which houses an electric element consisting of a stator and a rotor on the upper side of a hermetic container and a rotary compression element including a discharge valve and a cylinder on the lower side, the outer periphery of the stator serving as a passage of discharge gas. Of the gas passage groove, the through hole, or the gas passage hole of the rotor has a spiral shape having a forward inclination angle θ, and its length is l · 1 / sin θ.
Is an integral multiple of the frequency pulsation wavelength that is twice the rotational frequency that is the fundamental frequency of the discharge pulsation, that is, l · 1 / sin θ = n · C / 2 (f−α), where: 1 is the product thickness of the stator or rotor [M] n: integer C: sound velocity in refrigerant [m / s] f: power supply frequency [Hz] α: slip frequency [Hz] θ: angle [rad], and by setting the angle θ from the above formula, A silencer mechanism for a rotary compressor, wherein discharge pulsations in the space inside the closed container above and below the stator are in phase to reduce a pressure difference due to pressure pulsations above and below the stator. .