EP1913258A2

EP1913258A2 - A compressor

Info

Publication number: EP1913258A2
Application number: EP06780312A
Authority: EP
Inventors: Nursel Karakaya; Sibel Odabas; Fatih Ozkadi; Emre Oguz
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2005-08-04
Filing date: 2006-08-03
Publication date: 2008-04-23
Also published as: WO2007015223A2; WO2007015223A3; BRPI0611232A2; KR100932255B1; CN101238291A; KR20080031492A; CN101238291B

Abstract

The present invention relates to a method for the leak-proof bonding of a connection pipe (8) produced of a soft and elastic material providing the fluid circulating in the refrigerant cycle in the compressors (1) to reach the suction muffler (5) from the compressor inlet pipe (6) and a muffler inlet pipe (7) produced of a hard plastic material.

Description

Description A COMPRESSOR

[1] The present invention relates to a hermetic compressor utilized in cooling devices.

[2] In the hermetic compressors utilized in the cooling devices, a suction muffler made of plastic material is used in attenuating the noise resulting from the refrigerant fluid and the refrigerant vapor with decreased temperature and pressure received from the evaporator is delivered to the suction muffler or the suction volume on the cylinder head by means of an elastic connection duct without being mixed with the overheated gases within the compressor casing. In these implementations, since the refrigerant fluid delivered from the evaporator is not mixed with the hot gases within the compressor casing, it reaches the cylinder unheated. However, pressure losses increase as it flows through the connection duct and the power needed for the start-up of the compressor increases, adversely affecting the performance. In the implementations where the refrigerant fluid is delivered directly to the suction muffler or the cylinder through the connection duct, the vibrations of the components such as the motor, crank, piston rod etc. within the compressor casing can be transmitted to the casing by way of the connection duct. The connection ducts are supported by additional connection parts to be able to function under vibrational and high temperature conditions for long periods of time; however these additional parts make the assembly of the compressor more difficult, sufficient performance cannot be achieved due to the small size of the casing and other geometric limitations. The connection ducts connecting the compressor inlet and the suction muffler have to be produced of an elastic and leak-proof material since they have to function in an overheated environment like the compressor casing for long periods of time and for attenuating the vibrational movements. In the production of the connection ducts joining the vibrational components, elements that can provide a certain elasticity are used. However, the desired outcome for long term functioning and durability cannot be achieved. The flexible connection ducts are attached to a rigid duct within the compressor and after some period of time deformation is observed at the joints of flexible and rigid ducts under the environmental conditions of overheated gases within the compressor and the desired leak-proofing and elasticity cannot be achieved.

[3] In the United States Patent no. US4160625, a direct suction system implemented in the hermetic compressors is described. In this system, the suction port of the cylinder head is directly connected to the compressor inlet by way of a connecting pipe and the refrigerant is aimed to be delivered to the cylinder without being heated. This connecting pipe situated between the pipe extending from the suction port of the cylinder head and the pipe forming the compressor inlet, attenuates the movements of the compressor body by means of the o-rings and radial recesses at each end forming articulated joints with the other metallic fittings.

[4] In the United States Patent no. US5803717, a direct suction system is explicated which comprises a flange arranged with a certain angle to the suction connector at the inlet of the suction muffler, a telescopic tube having a leading end being in full contact with this flange, and a helical spring used for stabilizing the telescopic tube. By means of the gap left in between the compressor suction channel and the telescopic tube fitted into the compressor channel, the pressure inside the housing is balanced.

[5] In the United States Patent no. US6155800, a direct suction system is described in which the suction muffler is outside the hermetic shell and the gas from the muffler is delivered to the suction chamber by way of a flexible connection tube that can compress and extend like a bellows.

[6] In the United States Patent no. US4793775, a direct suction system is described that is formed by a bellows-like connector duct in between the compressor suction inlet pipe and the muffler inlet. After one end of the connector duct is fitted into the muffler inlet which is like a stopper, the other end is pressed into resilient engagement with the inner surface of the casing wall facing the compressor suction inlet pipe. In the case of oil accumulation in the connector duct, the end that bears on the casing is bended downwards to allow the oil to drain into the casing again.

[7] In the United States of America Patent no. US6390788, a description is given of a direct suction system utilized in the hermetic compressors which is formed by a coupling cap that connects a suction muffler to a compressor suction pipe with a plurality of external and internal pressure projections, the one at the top being inserted into the muffler having an elastic member to hold it in place and the bottom one having a limiting surface for firmly setting the coupling cap means on the suction muffler means. A helical spring arranged between the coupling cap and the compressor suction pipe provides for direct suction and pressure equalization, and attenuates the motor vibrations.

[8] The aim of the present invention is the realization of a compressor in which the circulating fluid returning from the refrigerant cycle is delivered to the suction muffler within by means of a leak-proof connection.

[9] The compressor realized in order to attain the aim of the present invention is explicated in the attached claims.

[10] In the compressor of the present invention, the circulating fluid returning from the refrigerant cycle enters into the compressor by means of a compressor inlet pipe and is delivered from here to the suction muffler and the cylinder head where it is sucked and pumped. A connection pipe, made of an elastic material such as rubber, between the compressor inlet pipe and the suction muffler is connected to the muffler inlet pipe having a rigid structure made of hard plastic material such that it is leak-proof and undislocatable by the motor vibrations in time. The connection pipe is joined by over injection to the muffler inlet pipe placed in an injection mould, forming a connection that is not affected by the hot gases within the environment of the compressor casing. In the connection of an elastic connection pipe, a rigid muffler inlet pipe, using additional connecting elements such as adhesives is not necessary. In fact, a more durable connection is achieved than the implementations wherein such elements are utilized.

[11] By way of the injection surface having rough and thus increased adhesion surface area on the muffler inlet pipe, the barrier surrounding the outer surface and injection channels on the barrier, better adhesion of the elastic connection pipe injected over the muffler inlet pipe to the plastered surfaces is provided and its dislocation is prevented.

[12] The compressor realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

[13] Figure 1 - is the sectional view of a compressor.

[14] Figure 2 - is the perspective view of a suction muffler, a muffler inlet pipe and a connection pipe.

[15] Figure 3 - is the sectional view of a suction muffler, a muffler inlet pipe and a connection pipe.

[16] Figure 4 - is the sectional view of a muffler inlet pipe

[17] Figure 5 - is the sectional view of a muffler inlet pipe and a connection pipe injected onto the muffler inlet pipe.

[ 18] Figure 6 - is the sectional view of a muffler inlet pipe in another embodiment of the present invention.

[19] Figure 7 - is the sectional view of a muffler inlet pipe and a connection pipe injected onto the muffler inlet pipe in another embodiment of the present invention.

[20] Figure 8 - is the schematic view of a connection pipe after injection in another embodiment of the present invention.

[21] Elements shown in figures are numbered as follows:

[22] 1. Compressor

[23] 2. Casing

[24] 3. Cylinder

[25] 4. Cylinder head

[26] 5. Suction muffler

[27] 6. Compressor inlet pipe

[28] 7. Muffler inlet pipe

[29] 8. Connection pipe

[30] 9. Injection surface [31] 10. Barrier

[32] 11. Coating extension

[33] 12. Injection channel

[34] 13. Injection extension

[35] 14. Injection cap

[36] The compressor (1) comprises a casing (2) that protects the movable components within, a cylinder (3) providing the suction and pumping of the circulating fluid, a cylinder head (4) situated on the cylinder (3), directing the sucked and pumped refrigerant fluid, a suction muffler (5) that attenuates the noise resulting from the circulating fluid, a compressor inlet pipe (6) that extends from outside the casing (2) to the interior, providing the entrance of the circulating fluid delivered from the evaporator, a muffler inlet pipe (7) one end of which extends into the suction muffler (5) allowing the entrance of the circulating fluid into the suction muffler (5), and a connection pipe (8) that connects the compressor inlet pipe (6) with the muffler inlet pipe (7), providing the delivery of the circulating fluid returning from the refrigerant cycle to the suction muffler (5) and attenuating the vibrations, having flexible or stepped structure, formed by over injection on a rigid muffler inlet pipe (7) placed in an injection mould wherein the joining procedure is made thereby providing a leak- proof joint between them.

[37] The muffler inlet pipe (7) is preferably produced as a single piece with the suction muffler (5) by injection moulding from TPE (thermoplastic elastomer) material that is rigid and not stretchable such as PBT (Polybutylene terephthalate) or PA (poly amide).

[38] The connection pipe (8) injected over the muffler inlet pipe (7) is produced of a soft and elastic material such as natural or synthetic rubber or from TPE (thermoplastic elastomer) containing a rubber additive.

[39] After the muffler inlet pipe (7) is placed in the injection mould in which the joining is made, the material for the connection pipe (8) is injected into the injection mould and after the connection pipe (8) material running in the mould reaches the muffler inlet pipe (7), it is bonded around the muffler inlet pipe (7) by being plastered over and consequently a connection pipe (8) - muffler inlet pipe (7) joint is formed which is durable in the overheated gas environment within the casing (2) (Figures 1 - 3).

[40] In another embodiment of the present invention, the muffler inlet pipe (7) comprises an injection surface (9) that forms the outer surface of its end whereto the connection pipe (8) is bonded by plastering over, the surface roughness increased by sandblasting or threading methods and providing the over injected material to adhere, a barrier (10) behind the injection surface (9), ring shaped and surrounding the muffler inlet pipe (7), making a boundary for the material of the connection pipe (8) that flows by plastering over the injection surface (9 (Figure 4). [41] In this embodiment, the connection pipe (8) comprises a coating extension (11) providing it to be joined to the injection surface (9), formed during the injection process, extending as an empty cylindrical shape outwards from the front of the connection pipe (8), and bearing on the barrier (10) by being plastered over the injection surface (9) (Figure 5).

[42] The coating extension (11) surrounds to plaster over the circumference of the injection surface (9), the surface roughness of which is increased and a more durable joint is attained between the connection pipe (8) and the muffler inlet pipe (7) during the injection process.

[43] In another embodiment of the present invention, the muffler inlet pipe (7) comprises one or more injection channels (12) situated on the barrier (10), extending from one surface of the barrier (10) to the other, and providing the material of the connection pipe (8) that bears on the barrier (10) to enter from one surface of the barrier (10) and exit from the other during the injection process (Figure 6).

[44] In this embodiment, the connection pipe (8) comprises one or more injection extensions (13) formed by the connection pipe (8) material filling in the injection channel (12) in the barrier (10) after the coating extension (11) reaches the barrier (10) during the injection process and one or more injection caps (14) that are formed at the ends of the injection extensions (13) as the material continues to flow and overflows going out from the injection channel (12) during the injection process (Figures 7 - 8).

[45] The injection extensions (13) and the injections caps (14) serve as elastic connection elements fixing the coating extension (11) to the barrier (10). While the compressor (1) is operating, injection surface (9) - the coating extension (11) joint between the connection pipe (8) and the muffler inlet pipe (7) is supported, guaranteeing that the coating extension (11) is not dislocated from the injection surface (9) and hence the connection pipe (8) is not dislocated from the muffler inlet pipe (7) during the high amplitude vibrational movements, furthermore the injection extensions (13) and the injection caps (14) contribute to the attenuation of the vibrations.

[46] By way of the connection pipe (8) being injected over the muffler inlet pipe (7) a durable and leak-proof connection pipe (8) - muffler inlet pipe (7) joint is formed that is not dislocated in the inner environment of the casing (2) by time and ease of assembly is achieved since utilization of other joining elements like glue, clamps etc. are not necessary.

Claims

[1] A compressor (1) comprising a casing (2) that guards the movable components within, a suction muffler (5) that attenuates the noise resulting from the circulating fluid, a compressor inlet pipe (6) that extends from outside the casing (2) into the interior, providing the entrance of the circulating fluid, and a muffler inlet pipe (7) one end of which extends into the suction muffler (5) allowing the entrance of the circulating fluid into the suction muffler (5), and characterized by a connection pipe (8) that connects the compressor inlet pipe (6) with the muffler inlet pipe (7), formed by over injection on a muffler inlet pipe (7) placed in an injection mould and providing a leak-proof joint between them.

[2] A compressor (1) as in Claim 1, characterized by a muffler inlet pipe (7) produced of TPE (thermoplastic elastomer) material that is rigid and not stretchable such as PBT (Polybutylene terephthalate) or PA (polyamide), and a connection pipe (8) produced of a soft and elastic material like natural or synthetic rubber or from TPE (thermoplastic elastomer). containing a rubber additive.

[3] A compressor (1) as in Claim 1, characterized by a muffler inlet pipe (7) comprising an injection surface (9) whereto the connection pipe (8) is bonded by plastering over, the surface roughness of which is increased by sandblasting or threading methods and providing the over injected material to adhere.

[4] A compressor (1) as in Claim 3, characterized by a muffler inlet pipe (7) comprising a barrier (10) behind the injection surface (9), ring shaped and surrounding the muffler inlet pipe (7), making a boundary for the material of the connection pipe (8) that flows by plastering over the injection surface (9).

[5] A compressor (1) as in Claim 4, characterized by a connection pipe (8) comprising a coating extension (11) providing it to be joined to the injection surface (9), formed during the injection process, extending like an empty cylindrical shape outwards from the front of the connection pipe (8), and bearing on the barrier (10) by being plastered over the injection surface (9).

[6] A compressor (1) as in Claim 4 and 5, characterized by a muffler inlet pipe (7) comprising one or more injection channels (12) situated on the barrier (10), extending from one surface of the barrier (10) to the other, and providing the material of the connection pipe (8) that bears on the barrier (10) to enter from one surface of the barrier (10) and exit from the other during the injection process.

[7] A compressor (1) as in Claim 6, characterized by a connection pipe (8) comprising one or more injection extensions (13) that are formed by the connection pipe (8) material filling in the injection channel (12) during the injection process and one or more injection caps (14) formed at the ends of the injection extensions (13) as the material continues to flow and overflows going out from the injection channel (12) during the injection process.