KR20010055304A - Apparatus for preventing vacuum compression of scroll compressor - Google Patents

Abstract

PURPOSE: A vacuum compression preventing device of a scroll compressor is provided to prevent breakage of a hermetic terminal due to vacuum compression and to avoid degradation of reliability due to thermal degradation of components by restraining vacuum compression with intermediate pressure. CONSTITUTION: A scroll compressor includes a high vacuum preventing unit. The high vacuum preventing unit comprises a valve housing(110) formed in a fixed scroll, a valve member(120) slidingly inserted into the valve housing to communicate an intake pressure section(Sl) with a discharge pressure section(Sh) of a casing or isolate the intake pressure section from the discharge pressure section, and an elastic member(130) interposed between the valve housing and the valve member to apply elasticity to sliding of the valve member. In over-compression or pump-down of the compressor, all the refrigerant gas in the intake pressure section is discharged to the discharge pressure section. Then, an intermediate pressure area(112) of the valve housing as well as an intermediate pressure chamber of a compression chamber is vacuumized. The addition of the pressure load applied to an intermediate pressure negative pressure face of the valve member and the elasticity of the elastic member is smaller than the pressure load of the discharge pressure section. The valve member is thrust toward the intermediate pressure area and a discharge pressure side gas hole(113a) is opened. Simultaneously, a portion of the discharge gas in the discharge pressure section backwardly flows to the intake pressure section through an intake pressure side gas hole(111a) after flowing into a discharge pressure area(113) of the valve housing. Thus, vacuum state of the compressor is removed. Thereafter, the valve member rebounds to the discharge pressure area against the pressure load of the discharge pressure section by the refrigerant gas returned to the intake pressure section. Thus, the intake pressure side gas hole and the discharge pressure side gas hole are closed.

Description

Vacuum Compression Prevention Device of Scroll Compressor {APPARATUS FOR PREVENTING VACUUM COMPRESSION OF SCROLL COMPRESSOR}

The present invention relates to an apparatus for preventing vacuum compression of a scroll compressor, and more particularly, to an apparatus for preventing vacuum compression of a scroll compressor that blocks the vacuum compression of the compressor by using an intermediate pressure.

Generally, a compressor converts mechanical energy into compressive energy of a compressive fluid, which is divided into reciprocating, scrolling, and centrifugal (commonly referred to as turbo) and vane (commonly referred to as rotary). .

Among the scroll compressors, unlike the reciprocating type using the linear motion of the piston, the scroll compressor sucks and discharges the gas by using a rotating body such as a centrifugal type or a vane type. The scroll compressor is divided into a low pressure scroll compressor or a high pressure scroll compressor depending on whether suction gas or discharge gas is filled in the casing.

In the low pressure scroll compressor, as shown in FIG. 1, the upper frame 2 and the lower frame 3 are respectively fixed to upper and lower sides of the inner circumferential surface of the casing 1 filled with oil to an appropriate height, and the upper frame 2 A driving motor 4 consisting of a stator 4A and a rotor 4B is fixedly installed between the lower frame 3 and the lower frame 3, and a driving shaft 5 is formed at the center of the rotor 4B of the driving motor 4. The turning frame 6 is press-fitted through the upper frame 2, and the upper frame 2 is formed on the upper surface with a wrap 6a in an involute curve to be eccentrically coupled to the drive shaft 5. A fixed scroll which is rotatably mounted and provided with an involute curve wrap 7a formed on the upper surface of the swing scroll 6 to be engaged with the wrap 6a of the swing scroll 6 to form a plurality of compression chambers ( 7) is fixedly installed on the edge of the upper frame (2), the casing (1) on the upper side of the fixed scroll (7) The high and low pressure separating plate 8 which divides the inside into the discharge pressure region which is a high pressure part and the suction pressure area which is a low pressure part is fixed to the inner peripheral surface of the casing 1.

At one outer periphery of the fixed scroll (7) is formed a suction groove (7b) in communication with the suction pipe (SP) to the inside of the outermost wrap, the center of the fixed scroll (7) is in communication with the discharge pipe (DP) A discharge port 7c is formed, and a check valve assembly 9 for opening and closing the discharge port 7c is provided at the front end surface of the fixed scroll 7.

In the figure, 5a, which is not described, is an oil oil, and 8a is a gas discharge hole.

The conventional scroll compressor configured as described above operates as follows.

That is, while the rotor 4B rotates together with the drive shaft 5 inside the stator 4A by the applied power, the turning scroll 6 is eccentrically rotated by an eccentric distance, and the turning scroll ( 6) is rotated by the distance from the center of the shaft by the Old Daming (unsigned) as the turning radius, and a plurality of compression chambers are formed between the two wraps (6a, 7a) with the fixed scroll (7). This compression chamber is moved to the center by the continuous turning motion of the turning scroll 6 to reduce the volume to further compress and discharge the sucked refrigerant gas.

Looking at this in more detail, the suction gas filled in the suction pressure region of the casing 1 through the suction pipe (SP) through the suction groove (7b) of the fixed scroll (7) opened during the swinging movement of the swinging scroll (6) The suction gas is sucked into the outer compression chamber, and the suction gas is gradually compressed along the compression chamber and discharged through the discharge port 7c to the discharge pressure region, which discharges the gas while the check valve assembly 9 is opened. The gas is discharged to the refrigeration cycle system through the gaseous discharge hole 8a of the low pressure separating plate 8 and the discharge pipe DP.

At this time, the check valve assembly 9 is kept open by the high-pressure discharge gas continuously discharged from the compression chamber during the normal operation of the compressor, but during the abnormal operation of the compressor (over-compression or high vacuum operation) discharge chamber As the pressure of the pressure becomes relatively higher than that of the compression chamber, the check valve assembly 9B blocks the discharge port 7a of the fixed scroll 7 to prevent the reverse flow of the discharge gas.

However, during the overcompression operation caused by other factors during the operation of the compressor or during the pump-down operation in which the service (suction) valve is closed, all refrigerant gas remaining in the suction pressure region is sucked into the compression chamber and discharged to the discharge pressure region. As a result of the discharge, the suction pressure region of the casing 1 as well as the compression chamber gradually become a vacuum state. If such abnormal operation is continued for a long time, the vacuum of the suction pressure region and the compression chamber is accelerated and the hermetic terminal is formed by vacuum compression. ) (Not shown) is damaged, or the tip chamber and the like is damaged by recompression at the compression mechanism portion, resulting in a problem that the reliability of the compressor is lowered.

The present invention has been made in view of the problems of the conventional low-pressure scroll compressor as described above, to provide a vacuum compressor preventing device of the scroll compressor that can prevent the suction pressure region is highly vacuumed during operation of the compressor. have.

1 is a longitudinal sectional view showing an example of a conventional scroll compressor.

Figure 2 is a partial longitudinal cross-sectional view showing an example of a scroll compressor with a vacuum compression prevention device of the present invention.

3 is an enlarged view showing detail "A" of FIG.

Figures 4a and 4b is a partial longitudinal cross-sectional view for the normal operation in the scroll compressor equipped with a vacuum compression preventing device of the present invention and a degree of freedom for the vacuum compression preventing device.

5A and 5B are partial longitudinal cross-sectional views for abnormal operation (high vacuum operation) in a scroll compressor equipped with the vacuum compression preventing device of the present invention and degrees of freedom for the vacuum compression preventing device.

** Description of symbols for the main parts of the drawing **

1: casing 6: turning scroll

6a: lap of turning scroll 10: fixed scroll

11: Wrap of fixed scroll 12: Suction groove

13: discharge port 100: high vacuum prevention means

110: valve housing 111a: suction gas side gas hole

112: intermediate pressure space 112a: intermediate pressure side gas hole

113: discharge pressure space 113a: gas hole on the discharge pressure side

120: valve member 121: volume protrusion

130: elastic member 140: housing stopper

S _l : suction pressure zone S _m : medium pressure zone

S _h : discharge pressure range

In order to achieve the object of the present invention, there is provided a fixed scroll to form a plurality of compression chambers together with the turning scroll and its turning scroll in the casing, so that each compression chamber has a different pressure during turning of the turning scroll. A scroll compressor configured to move a position in a;

A valve housing which is formed between the suction pressure region and the discharge pressure region of the casing, and the intermediate pressure region in which the compression proceeds is communicated with each other, and is inserted in sliding contact with the inner circumferential surface of the valve housing; Interposed between the valve member for communicating or blocking the suction pressure region and the discharge pressure region with each other while moving according to the pressure change of the intermediate pressure region according to the operation state of the compressor, and between the valve housing for supporting the valve member. Is composed of an elastic member to reinforce the movement of the valve member,

The valve housing is provided with a vacuum compressor preventing device of a scroll compressor, characterized in that the upper and lower sides are formed by the valve member to be divided into the intermediate pressure space and the discharge pressure space to have the valve flow space in the longitudinal direction.

Hereinafter, a vacuum compression prevention device of a scroll compressor according to the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

Figure 2 is a partial longitudinal cross-sectional view showing an example of a scroll compressor with a vacuum compression prevention device of the present invention, Figure 3 is an enlarged view showing the "A" part of FIG.

As shown therein, the low-pressure scroll compressor equipped with the vacuum compression preventing device according to the present invention includes a fixed scroll (10) having a high vacuum preventing means (100) on the upper frame (2) fixed inside the casing (1). ) Is fixed, and the rotating scroll (6) together with the fixed scroll (10) to form a plurality of compression chambers is integrated with a rotor (not shown) of a drive motor (not shown) mounted to the casing (1). It is mounted on the upper frame (2), the high and low pressure separating plate partitioning the inside of the casing (1) to the suction pressure region (S _l ) and the discharge pressure region (S _h ) on the upper side of the fixed scroll ( 8) is fixed to the casing (1), and the check valve assembly (9) is installed on the distal end surface of the discharge port 13 of the fixed scroll (10) to prevent the back flow of the discharge gas.

The high vacuum preventing means 100 is inserted into the valve housing 110 formed in the fixed scroll 10 and the valve housing 110 to slide in the suction pressure region S _l of the casing 1. An elastic force for sliding of the valve member 120 interposed between the valve member 120 and the valve housing 110 and the valve member 120 for communicating or blocking the discharge pressure region S _h with each other. It consists of an elastic member 130 for adding.

The valve housing 110 is formed as a valve flow space in the longitudinal direction so that the upper and lower sides thereof are respectively divided into the intermediate pressure space 112 and the discharge pressure space 113 by the valve member 120, the valve housing 110 ) Is formed on the main surface of the valve member 120, the suction pressure side gas hole 111a which is opened and closed by the main surface of the valve member 120 and communicates with the suction pressure region S _l of the casing 1, and the bottom surface of the intermediate pressure space 112 is The intermediate pressure side gas hole 112a communicating with the intermediate pressure region S _m of the casing 1 is formed, and the discharge pressure region S _h of the casing 1 is formed on the upper surface of the discharge pressure space 113. The discharge pressure side gas hole 113a which is in communication with and opened and closed by the valve member 120 is formed.

The suction pressure side gas hole 111a is formed through the outer circumferential surface of the fixed scroll 10, and the intermediate pressure side gas hole 112a is the intermediate pressure in the plurality of compression chambers including the turning scroll 6 and the fixed scroll 10. It is formed through the intermediate pressure chamber forming the area (S _m ), the discharge pressure side gas hole 113a is formed through the back of the fixed scroll (10).

In addition, the upper side surface of the valve housing 110 is opened and covered with a disc shaped housing plug 140, and the discharge pressure side gas hole 113a is formed at the center of the housing plug 140, but the discharge is performed. It is preferable that the diameter of the pressure side gas hole 113a is formed at least smaller than the cross-sectional area of the suction pressure negative pressure surface of the valve member 120.

The valve member 120 is inserted in sliding contact with the inner circumferential surface of the valve housing 110, and an O-ring (not shown) for sealing with the valve housing 110 is inserted into the outer circumferential surface thereof, and the discharge pressure side gas hole 113a is inserted into the valve member 120. It is preferable that the volume protrusion 121 is formed on the upper surface corresponding to the inner end of the bottom side so as to slide in the discharge pressure side gas hole 113a to reduce the dead volume.

The elastic member 130 is interposed in the intermediate pressure space 112 of the valve housing 110, but in the normal operation of the compressor, the valve member 120 is in close contact with the inner bottom of the housing cap 140, the valve housing 110 It is preferable that the discharge pressure space 113 is formed to have a length within which is removed.

In the drawings, the same reference numerals are given to the same parts as in the prior art.

In the drawings, reference numeral 5 denotes a drive shaft, 6a a lap of the turning scroll, 11 a lap of the fixed scroll, and 12 a suction groove.

The general operation of the scroll compressor provided with the vacuum compression preventing device of the present invention as described above is similar to the conventional.

That is, while the driving shaft 5 rotates together with the rotor (not shown) of the motor rotated by the applied power, the pivoting scroll 6 is eccentrically rotated by an eccentric distance, but the pivoting scroll 6 is the shaft center. The refrigerant gas filled in the low pressure part of the casing 1 as a plurality of compression chambers are formed between the two wraps 6a and 10a with the fixed scroll 10 as the turning motion is performed at a distance separated by the turning radius. Is sucked and discharged to the discharge port 13 of the fixed scroll (10).

4A and 4B, in the normal operation of the compressor, the refrigerant gas flows into the intermediate pressure space 112 of the valve housing 110 through the intermediate pressure side gas hole 112a and the valve member 130. Since the pressure of the intermediate pressure negative pressure surface of the valve member 120 is increased, the combined force of the pressure load (P _m × A) applied to the intermediate pressure negative pressure surface of the valve member 120 and the elastic force (F _k ) of the elastic member 130 is The valve member 120 blocks the discharge pressure side gas hole 113a by being greater than or equal to the pressure load P _h × A of the discharge pressure region S _h applied to the rear surface. Through this, the high pressure gas of the discharge pressure region S _h flows into the discharge pressure space 113 of the valve housing 110 through the discharge pressure side gas hole 113a and is sucked through the suction pressure side gas hole 111a. The backflow to the pressure region S _{1 can} be prevented. Here, as the volume protrusion 121 of the valve member 120 slides into the discharge pressure side gas hole 113a, the dead volume of the discharge pressure region S _h is reduced.

On the other hand, as shown in FIGS. 5A and 5B, when the compressor is overcompressed or pumped down, all the refrigerant gas in the suction pressure region S ₁ including the compression chamber is discharged to the discharge pressure region S _h . In addition to the intermediate pressure chamber of the compression chamber, the intermediate pressure space 112 of the valve housing 110 also becomes a vacuum state, and a pressure load (P _m × A) applied to the intermediate pressure negative pressure surface of the valve member 120. The combined force of the elastic force (F _k ) of the elastic member 130 is smaller than the pressure load (P _h × A) of the discharge pressure region (S _h ) applied to its rear surface, so that the valve member 120 is the intermediate pressure The discharge pressure side gas hole 113a is opened while being pushed into the space 112, and at the same time, a part of the discharge gas in the discharge pressure region S _h passes through the discharge pressure side gas hole 113a to discharge pressure of the valve housing 110. Flowed into the space 113, and flowed back into the suction pressure region S _l through the suction gas side gas hole 111, The vacuum is released.

Thereafter, the valve member 120 is pushed back into the discharge pressure space 113 by overcoming the pressure load (P _h × A) of the discharge pressure region (S _h ) by the refrigerant gas introduced into the suction pressure region (S _l ). In addition, the suction pressure side gas hole 111a and the discharge pressure side gas hole 113a are blocked again.

On the other hand, if the power is not turned off during the vacuum compression of such a compressor, the drive motor (unsigned) of the compressor is continuously rotated, and the compressor is vacuum compressed again. The valve member 120 is continuously reciprocated at a predetermined frequency in the valve housing 110 while repeating a series of operations in which the state is released.

In this way, it is possible to prevent the compression chamber including the suction pressure region of the casing from being in a vacuum state, thereby preventing damage to the hermetic terminal due to vacuum compression, and also to deteriorate components generated during recompression of the compression mechanism. And thereby the reliability of the compressor can be prevented in advance.

The apparatus for preventing vacuum compression of a scroll compressor according to the present invention includes a valve housing provided to have a valve flow space in a longitudinal direction of the hard plate portion of the fixed scroll so that the suction pressure region, the intermediate pressure region and the discharge pressure region of the casing communicate with each other; A valve member which is slidably inserted into the inner circumferential surface of the valve housing and communicates or blocks the suction pressure region and the discharge pressure region with each other according to the pressure change of the intermediate pressure region according to the operation state of the compressor, and supports the valve member. It is composed of an elastic member interposed between the side of the valve housing and the valve member to reinforce the sliding movement of the valve member, thereby preventing damage to the hermetic terminal due to vacuum compression generated when the suction pressure region is vacuumed. The deterioration of parts due to the recompression of the compression mechanism and the decrease in reliability of the compressor It can prevent it beforehand.

Claims (5)

In the scroll compressor is provided with a rotating scroll and a fixed scroll for forming a plurality of compression chambers together with the rotating scroll in the casing so that each of the compression chambers have different pressures during the turning of the rotating scroll to move the position continuously. In; A valve housing which is formed between the suction pressure region and the discharge pressure region of the casing, and the intermediate pressure region in which the compression proceeds is communicated with each other, and is inserted in sliding contact with the inner circumferential surface of the valve housing; Interposed between the valve member for communicating or blocking the suction pressure region and the discharge pressure region with each other while moving according to the pressure change of the intermediate pressure region according to the operation state of the compressor, and between the valve housing for supporting the valve member. Is composed of an elastic member to reinforce the movement of the valve member, The valve housing is a vacuum compressor preventing device of a scroll compressor, characterized in that the upper and lower sides are formed by the valve member to be divided into the intermediate pressure space and the discharge pressure space to have a valve flow space in the longitudinal direction. 2. The valve housing according to claim 1, wherein the valve housing has a suction pressure side gas hole that is opened and closed by a valve member on the main surface thereof and communicates with the suction pressure region, and the intermediate pressure side gas hole communicates with the intermediate pressure region of the casing in the intermediate pressure space. And a discharge pressure side gas hole which is opened and closed together with the suction pressure side gas hole by the valve member in communication with the discharge pressure region of the casing in the discharge pressure space thereof. 3. The vacuum compression preventing device of a scroll compressor according to claim 2, wherein the discharge pressure side gas hole is formed smaller than the inner diameter of the valve housing so that the cross-sectional area of the discharge pressure negative pressure surface of the valve member is smaller than the cross-sectional area of the suction pressure negative pressure surface. . The apparatus of claim 3, wherein a volume protrusion is formed on one side of the valve member corresponding to the inner end of the discharge pressure side gas hole so as to slide into the discharge pressure side gas hole. . The vacuum compressor preventing device of a scroll compressor according to claim 1, wherein the elastic member is interposed in the intermediate compression space of the valve housing.