WO2009157594A1

WO2009157594A1 - Apparatus for controlling refrigerant flow in air conditioner having multiple compressors

Info

Publication number: WO2009157594A1
Application number: PCT/KR2008/003574
Authority: WO
Inventors: Kyung Ki Min; Jae Heung Yoo
Original assignee: Carrier Corporation
Priority date: 2008-06-23
Filing date: 2008-06-23
Publication date: 2009-12-30
Also published as: KR20110014263A

Abstract

The present invention relates to an apparatus for controlling a refrigerant flow in an air conditioner having multiple compressors. The air conditioner according to the prior art, which comprises a plurality of compressors, has a problem in that serious noise occurs at the confluence of discharge lines from multiple compressors. The apparatus for controlling refrigerant flow in the air conditioner according to an embodiment of the present invention is provided at the confluence of the discharge lines from multiple compressors, wherein said apparatus comprises a muffler having a plurality of refrigerant inlets and one refrigerant discharge outlet. By using the present invention, noise may be reduced at the confluence of the discharge lines from the multiple compressors.

Description

APPARATUS FOR CONTROLLING REFRIGERANT FLOW IN AIR CONDITIONER HAVING MULTIPLE COMPRESSORS

Technical Field

[1] The present invention relates to an apparatus for controlling a refrigerant flow in an air conditioner comprising multiple compressors. More particularly, the present invention relates to an apparatus for controlling a refrigerant flow, which is coupled to discharge lines of the discharge side of a compressor of an air conditioner, wherein the multiple compressors are selectively paused or operated to thereby vary the capacity of cooling or heating. Background Art

[2] There is provided in the art a variable air conditioner comprising multiple compressors, which switchably pauses or operates according to necessary loads in order to effectively respond to cooling or heating as demanded.

[3] Fig. 1 illustrates such an air conditioner of the prior art. It is possible that multiple compressors (2, 4) operate simulataneously according to cooling/heating loads, or that only one suitable compressor selectively operates, thereby transferring the compressed refrigerant to the condenser (14). The lines for discharging a refrigerant from the multiple compressors (2, 4) join together at one point (16) and then continue to be coupled to the condenser (14) via a line. The lines for discharging the refrigerant from the multiple compressors are each provided with a muffler (6, 8) and a check valve (10, 12). The pressure pulsation of the refrigerant discharged from the compressor diminishes in the space formed inside the muffler (6, 8), thereby reducing the noise generated at the line due to the pressure pulsation. When only one compressor operates among the multiple compressors (2, 4), the check valve (10, 12) prevents the refrigerant discharged from the compressor, which is in operation, from reversely flowing into the discharge line at the compressor in pause. The muffler and the check valve may be provided in the proximity of the refrigerant discharge outlet formed inside the compressor casing.

[4] Further, when the muffler (6, 8) and the check valve (10, 12) are individually provided to the multiple discharge lines connected to the multiple compressors (2, 4), said conventional air conditioner causes some problems, e.g., delaying work time for connecting the refrigerant line to the muffler (6, 8) and the check valve (10, 12), increasing risk of refrigerant leakage due to numerous connections, etc.

[5] U.S. Patent No. 5,208,429 introduces a device wherein the check valve is integrated into the refrigerant inlet side of the muffler. The refrigerant inlet of the muffler is directly connected to the refrigerant discharge outlet formed on the outside of the refrigerant discharge outlet. Further, the check valve, which is disposed at the refrigerant inlet of the muffler, prevents the refrigerant from flowing in a reverse direction.

[6] Korean Laid-Open Patent Publication No. 10-2006-0082454 discloses a check valve

(50) of an air conditioner, wherein the check valves individually provided to two discharge lines of a compressor are integrated into one. The check valve (50) shown in Fig. 2 comprises the following: two inlet lines (52, 53) through which a refrigerant flows in from each of the different compressors, said inlet lines facing opposite sides from each other; and an outlet line (54) arranged to be normal to said inlet lines and allowing the refrigerant to flow therethrough into a condenser, wherein said check valve is shaped in a T-Letter. A ball (56) is arranged at a confluence between said inlet lines (52, 53). Each of the inlet lines (52, 53), which is disposed at the left and right around the ball (56), is provided with a flow passage forming member (60, 62) having a refrigerant flow passage with a diameter smaller than that of the ball (56). Also, the outlet line (54) is mounted with a blocking member (58) having a through-hole (58a).

[7] The check valve (50) is provided at a confluence of the discharge line from the two compressors. When only one of the two compressors is in operation, the pressure of the refrigerant discharged from the compressor moves the ball (56) to the flow passage forming member (60) disposed on the side from which the refrigerant does not flow. Said refrigerant pressure further places the ball into a groove (64), thereby closing the inlet line on such side. By doing so, the refrigerant is prevented from reversely flowing into the inlet line through which the refrigerant does not flow. When the two compressors are both in operation to thereby allow the refrigerant to flow from both the left and right inlet lines (52, 53), the ball (56) is moved to the location between said flow passage forming members (60, 62) by the refrigerant pressure flowing in from both sides through the inlet lines (52, 53). The refrigerant flowing in through the inlet lines (52, 53) on both sides further flows to the outlet line (54).

[8] However, the ball (56) and the flow passage forming member (60) form a seal having a narrow area in such a check valve (50). This potentially causes a problem in that the refrigerant leaks through a fine gap generated due to machining tolerance and reversely flows into the compressor in pause. Further, since the ball (56) forms the seal only by the pressure of the refrigerant flowing in, the seal may be insufficient when the refrigerant pressure is weak.

[9] Further, the turbulent flow created by the abrupt change in the flow of the refrigerant at the confluence, where the discharge lines of the multiple compressors meet, may cause a loud noise. The noise may become louder when the pressure pulsations from the multiple compressors overlap with each other. Disclosure of Invention

Technical Problem

[10] An object of the present invention is to solve the problem of the prior art. In this regard, the present invention provides an apparatus for controlling a refrigerant flow in an air conditioner comprising multiple compressors capable of diminishing noises at the confluence of discharge lines of the multiple compressors.

[11] Another objective of the present invention is to provide an apparatus for controlling a refrigerant flow in an air conditioner comprising multiple compressors capable of preventing the refrigerant from flowing from the compressor in operation into the compressor in pause. Technical Solution

[12] In order to achieve such objectives, the apparatus for controlling a refrigerant flow in an air conditioner includes a muffler provided at the confluence of the discharge outlet lines of the multiple compressors. Such a muffler has a plurality of refrigerant inlet holes and a refrigerant discharge hole.

[13] In addition, the apparatus for controlling a refrigerant flow in an air conditioner may further comprise a check valve mounted in the proximity of each of the refrigerant inlet holes of the muffler, thereby opening the refrigerant inlet holes when the refrigerant flows from the compressor and closing the refrigerant inlet holes when the refrigerant discharge discontinues.

Advantageous Effects

[14] According to the apparatus for controlling the refrigerant flow of the present invention, the muffler is provided at the confluence where the discharge lines of multiple compressors meet, thereby diminishing noises caused by the turbulent flow created at the confluence of the discharge lines of the multiple compressors. Moreover, at the confluence where the discharge lines of the multiple compressors meet, the pressure pulsations from the multiple compressors may overlap with each other, thus causing noises to be louder due to the pressure pulsation. However, due to the muffler provided at the confluence of the discharge lines of the multiple compressors, the overlapped pressure pulsations may effectively diminish, thereby reducing noises.

[15] Additionally, when the refrigerant flows in the apparatus only from one of the multiple compressors, the check valve at the compressor in pause receives the force by the pressure of the refrigerant discharged from the compressor in operation, in addition to the elastic restoring force of its own. This allows the check valve to tightly fit into the valve seat, thereby preventing the refrigerant's reverse flow.

[16] Further, the check valve and the mufflers can be integrated into one unit, thus reducing the number of parts and the number of connections of discharge lines. This increases the efficiency of assembling the air condition system and decreases the likelihood of refrigerant from leaking. Brief Description of the Drawings

[17] Fig. 1 shows a conventional air conditioner comprising multiple compressors.

[18] Fig. 2 shows a conventional check valve.

[19] Fig. 3 is a cross sectional view of an apparatus for controlling a refrigerant flow according to a first embodiment of the present invention.

[20] Fig. 4 shows the apparatus for controlling the refrigerant flow according to the first embodiment of the present invention, wherein both first and second compressors are in operation.

[21] Fig. 5 shows the apparatus for controlling the refrigerant flow according to the first embodiment of the present invention, wherein only the first compressor is in operation.

[22] Fig. 6 shows the apparatus for controlling the refrigerant flow according to the first embodiment of the present invention, wherein only the second compressor is in operation.

[23] Fig. 7 shows an apparatus for controlling a refrigerant flow according to a second embodiment of the present invention.

[24] Fig. 8 shows an apparatus for controlling a refrigerant flow according to a third embodiment of the present invention. Mode for the Invention

[25] Fig. 3 illustrates an apparatus (100) for controlling a refrigerant flow according to a first embodiment of the present invention.

[26] The apparatus (100) for controlling a refrigerant flow comprises a muffler (115), which includes: a first body portion (110) having a refrigerant discharge hole connected to the refrigerant inlet line (190) of a condenser; and a second body portion (120) having two refrigerant inlet holes (150, 160) connected to the refrigerant discharge outlet lines (130, 140) of compressors. The inner space encircled by the first body portion (110) and the second body portion (120) forms a space, which is more enlarged than that of the refrigerant discharge outlet lines (130, 140) of the compressor. In this space, the pressure pulsation of the refrigerant discharged from the compressor diminishes.

[27] The first body portion (110) and the second body portion (120), the refrigerant discharge outlet lines (130, 140) of the compressor and the second body portion (120), and the first body portion (110) and the refrigerant inlet line (190) of the condenser are seal-combined by using a known means such as welding or other capable means of sufficiently preventing the refrigerant from leaking.

[28] Each of the refrigerant inlet holes (150, 160) of the second body portion (120) is provided with a leaf spring (170) as a check valve to open or close the refrigerant inlet holes (150, 160). The leaf spring (170) opens the refrigerant inlet hole (150, 160) by the pressure of the refrigerant discharged from the compressor, wherein said leaf spring has elasticity proper to close the outlet based on the restoring force when the refrigerant discharge discontinues. Such a leaf spring (170) is made from aluminum, steel, etc.

[29] The refrigerant inlet holes (150, 160) are provided with protrusions formed around the circumference so as to provide a valve seat surface. The valve seat surface is configured to provide a sealing surface with the leaf spring (170), which is large enough to prevent the refrigerant from leaking. The leakage of the refrigerant can be sufficiently prevented when the area of a surface contact is at least 60% of the hole area of the refrigerant inlet holes (150, 160). The portion seated into the valve seat of the muffler (115) of the leaf spring (170) is formed to be relatively large so as to smoothly make surface contact and to be evenly applied by the refrigerant pressure operating on the rear surface. However, the other portions are formed to have small widths so as to flexibly bend.

[30] A valve stopper (180) is provided at the upper side of the leaf spring (170). One end of the valve stopper is secured to the proximity of the refrigerant inlet holes (150, 160) of the muffler (115), while the other end is placed apart from the refrigerant inlet holes (150, 160). Said one end of the leaf spring (170) and one end of the valve stopper (180) are secured together to the second body portion (120) of the muffler (115) by means of a bolt (200). The valve stopper (180) puts a limit on the opening height of the leaf spring (170).

[31] The flow passage of the refrigerant of the refrigerant inlet holes (150, 160) is provided with a Helmholtz resonator (195). For this constitution, the second body portion (120) of the muffler (115) consists of a first member (122) and a second member (124). The surface of the second member (124), which contacts the first member (122), is provided with a groove as the resonance tube of the Helmholtz resonator (195). Otherwise, the groove may be separately formed on the first member (122) and the second member (124), or only on the first member (122). Due to such a structure comprising both the muffler (115) and the resonator (195), the apparatus (100) for controlling the refrigerant flow can diminish the low-frequency noise in the space formed inside the muffler (115) as well as the high-frequency noise in the Helmholtz resonator (195). When the high-frequency noise is sufficiently eliminated by the resonator inside the compressor before the confluence of the discharge lines of the multiple compressors, the resonator (195) may not be required in the apparatus (100) for controlling the refrigerant flow.

[32] The operation of the apparatus (100) for controlling the refrigerant flow is explained with reference to Figs. 4-6.

[33] Fig. 4 illustrates the first and second compressors (210, 220), which are in operation.

[34] Here, all the leaf springs in the first and second compressors (210, 220) open the refrigerant inlet holes, thereby allowing the refrigerant discharged from the first and second compressors (210, 220) to flow into the apparatus (100) for controlling the refrigerant flow.

[35] Fig. 5 illustrates the operation of only the first compressor (210), while Fig. 6 illustrates the operation of only the second compressor (220). As shown in the Figures, when only one of the first and second compressors (210, 220) operates, only the leaf spring with the pressure of the refrigerant from the refrigerant discharge line connected to the compressor in operation opens the refrigerant inlet holes. This allows the refrigerant to flow into the apparatus (100) for controlling the refrigerant flow. Further, the leaf spring on the compressor in pause maintains its state of being closed by the refrigerant pressure inside the apparatus (100) and the elastic restoring force of the leaf spring itself. Here, the leaf spring on the compressor in pause receives the force by the pressure of the refrigerant discharged from the compressor in operation, in addition to its own elastic restoring force, all of which allow the leaf spring on the compressor in pause to more tightly fit into the valve seat. This prevents the refrigerant from flowing in a reverse direction.

[36] Fig. 7 illustrates an apparatus (100) for controlling a refrigerant flow according to a second embodiment of the present invention. Two of the leaf springs are arranged side by side along the width direction, thereby allowing the sectional area of the muffler (115) to be smaller than that of the first embodiment where the two leaf springs are arranged in a longitudinal direction.

[37] Fig. 8 illustrates an apparatus (100) for controlling a refrigerant flow according to a third embodiment of the present invention. The apparatus (100) for controlling the refrigerant flow of the third embodiment is used for an air conditioner employing three compressors and comprises three refrigerant inlet holes so as to be connected to each of the refrigerant discharge lines (140) from the three compressors. At the three refrigerant inlet holes, three leaf springs (170) are provided side by side along the width direction as in the second embodiment.

[38] The present invention has been explained based on the embodiments. It is obvious that the present invention may be practiced in various forms, not limited to the embodiments, without going beyond the scope. For instance, the present invention may be applied to an air conditioner comprising four or more compressors. It may also have the second body portion of the muffler formed as an integrated unit through casting so as to receive the Helmholtz resonator inside thereof. Further, instead of the leaf spring, the check valve of the present invention may be replaced with any of the already known means. [39]

Claims

[I] An apparatus for controlling a refrigerant flow in an air conditioner comprising multiple compressors, wherein said apparatus is provided at a confluence of discharge lines of the multiple compressors, and wherein said apparatus includes a muffler having a plurality of refrigerant inlet holes and a refrigerant outlet hole.

[2] The apparatus according to Claim 1, further comprising a check valve provided in the proximity of each of the refrigerant inlet holes of said muffler, thereby opening the refrigerant inlet holes when the refrigerant is discharged from the compressor and closing the refrigerant inlet holes when the refrigerant discharge discontinues.

[3] The apparatus according to Claim 2, wherein said check valve is made from an elastic material, thereby opening the refrigerant inlet holes by discharge pressure when the refrigerant is discharged from the compressor and closing the refrigerant inlet holes by the elastic restoring force when the refrigerant discharge discontinues.

[4] The apparatus according to Claim 3, wherein a valve seat is formed at a circumference of the refrigerant inlet holes, and wherein said check valve makes surface contact with said valve seat when it is closed.

[5] The apparatus according to Claim 4, wherein when the check valve is closed, the area of the portion making surface contact with said valve seat is at least 60% of the area of said refrigerant inlet holes.

[6] The apparatus according to Claim 5, wherein the valve seat is a protrusion formed at the circumference of the refrigerant inlet holes.

[7] The apparatus according to Claim 2, wherein the check valve is a leaf spring.

[8] The apparatus according to Claim 7, wherein the check valve is a long leaf spring, and wherein the plurality of check valves are arranged side by side.

[9] The apparatus according to Claim 8, further comprising a valve stopper which puts a limit on the opening height of the check valve.

[10] The apparatus according to Claim 9, wherein one end of the check valve and one end of the valve stopper are secured together with a fixing means.

[I I] The apparatus according to Claim 10, wherein when the check valve is closed, the area of the portion making contact with the valve seat at the lower portion thereof is at least 60% of the area of said refrigerant inlet holes.

[12] The apparatus according to Claim 1, wherein the muffler includes a first body portion having a refrigerant outlet hole and a second body portion having refrigerant inlet holes, and wherein said second body portion further comprises a resonator communicating with a refrigerant flow passage of the refrigerant inlet holes.

[13] The apparatus according to Claim 12, wherein the second body portion of the muffler includes a first member and a second member, and wherein the contacting surface of at least one of the first and second members is provided with a groove in the shape of a resonance tube of the resonator.