EP3976965A1

EP3976965A1 - A hermetic compressor comprising a suction muffler

Info

Publication number: EP3976965A1
Application number: EP20736617.0A
Authority: EP
Inventors: Semih GUREL; Husnu Kerpicci; Ercan KURTULDU
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2019-05-31
Filing date: 2020-06-30
Publication date: 2022-04-06
Also published as: WO2020240048A1

Abstract

The present invention relates to a compressor (1) which is suitable for use in cooling devices such as refrigerators, comprising a casing (2) wherein the oil (14) is placed; a suction muffler (7) which is produced from plastic, which has a closed hollow volume and which enables the temperature of the refrigerant to be decreased and the noise to be attenuated; and barriers (11) which prevents the oil (14) from mixing into the refrigerant flowing through the suction muffler (7).

Description

A HERMETIC COMPRESSOR COMPRISING A SUCTION MUFFLER

The present invention relates to a hermetic compressor which is used in refrigerators and which comprises a suction muffler decreasing the refrigerant temperature and attenuating the noise originating from the refrigerant.
In the hermetic reciprocating compressors used in refrigerators, in order to decrease the abrasion of the movable mechanical components such as the cylinder, piston, crankshaft, piston rod and the bearings, oil is placed into the compressor casing wherein these components operate. With the operation of the crankshaft, the oil inside the compressor casing is carried upwards through the helical channels in the crankshaft. The oil scattered in the upper section of the compressor body drains into the lower part of the casing under the effect of the gravity and enables all the movable parts of the compressor such as the crankshaft to be lubricated. The oil decreases mechanical losses by preventing abrasion but also provides the cooling of components which cause excessive heating in the compressor. The compressor further comprises a suction muffler which produced from plastic, enabling the noise generated by the refrigerant to be attenuated and the temperature of the refrigerant to be decreased. The oil used for lubricating the mechanical parts in the compressor creates a critical problem when it leaks into the suction muffler and mixes with the refrigerant. The oil joins into the cooling cycle together with the refrigerant gas, decreasing the flow rate of the refrigerant and thus, decreasing the cooling capacity. Furthermore, the amount of oil inside the compressor is decreased depending on the amount of oil trapped in a section of the cooling system and this causes abrasion problems in the mechanical parts due to insufficient lubrication.
The Patent Application No. WO2016155799 (A1) relates to a suction muffler which is suitable for use in the hermetically sealed compressor of a cooling device.
The Patent No. EP2577190 (B1) relates to a compressor which is used in cooling devices, wherein the refrigerant-oil mixture inside the cylinder volume is separated into refrigerant and oil particles.
The Patent Application No. US5988990 relates to a hermetic compressor wherein the lubricating oil is separated from the refrigerant circulating in the refrigerant cycle at the inlet of the suction muffler by means of an oil separating apparatus.
The Patent Application No. EP2397693 (A1) relates to a hermetic compressor wherein the oil is separated from the refrigerant inside the suction muffler.
The Patent Application No. US2006045762 relates to a hermetic compressor wherein the liquid and oil components are separated from the refrigerant inside the suction muffler.
The aim of the present invention is the realization of a compressor wherein the oil is prevented from mixing with the refrigerant which passes through the suction muffler.
The compressor realized in order to attain the aim of the present invention comprises a plastic suction muffler which enables the temperature of the refrigerant being circulated in the cooling cycle to be decreased and the noise created by the refrigerant to be attenuated. The refrigerant gas transferred from the cooling system enters the suction muffler through an inlet opening. In order to prevent the oil moving inside the casing from entering the suction muffler, oil barriers are provided on the outer surface of the suction muffler. The oil barrier is produced as a single piece with the suction muffler or attached to the suction muffler body by means of plastic welding method. The suction muffler further comprises a slot wherein the oil separated from the refrigerant is collected and internal discharge holes which enable the oil collected in the slot to be discharged.
In the compressor of the present invention, the oil is prevented from entering the suction muffler by means of the oil barriers. The oil mixed into the refrigerant which is transferred into the suction muffler is separated from the refrigerant by means of the slot, thus preventing the delivery of oil into the cooling system. The oil level inside the compressor is prevented from decreasing and the efficiency of the compressor is improved.
The compressor realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
Figure 1 - is the cross-sectional view of a hermetic compressor.
Figure 2 - is the perspective view of the suction muffler.
Figure 3 - is the view of the inlet opening of the suction muffler.
Figure 4 - is the partial cross-sectional view of the suction muffler.
The elements illustrated in the figures are numbered as follows:

Compressor
Casing
Cylinder
Piston
Body
Crankshaft
Suction muffler
Inlet opening
Refrigerant flow tube
Lower discharge hole
Barrier
Slot
Inner discharge hole
Oil
Inlet tube
Rotor

The hermetic compressor (1) suitable to be used in cooling devices such as refrigerators comprises a casing (2) wherein the oil (14) used for lubricating the movable parts is placed; a cylinder (3) which is arranged in the casing (2) and which enables the refrigerant to be sucked and pumped; a piston (4) which operates in the cylinder (3); a body (5) which accommodates the cylinder (3) and the piston (4); an electric motor having a rotor (16) and a stator; a crankshaft (6) which is mounted to the hub of the rotor (16), which transfers the movement of the rotor (16) to the piston (4) and which is immersed into the oil (14) in the casing (2) from one end to enable the oil (14) to be transferred to the upper part of the body (5) and dispersed; a suction muffler (7) which is produced from plastic, which has a closed hollow volume and which enables the temperature of the refrigerant to be decreased and the noise to be attenuated; an inlet tube (15) and an inlet opening (8) which enable the refrigerant returning from the cooling cycle to be delivered into the suction muffler (7); a refrigerant flow tube (9) which extends from the inlet opening (8) into the suction muffler (7); and a lower discharge hole (10) which is arranged on the base of the suction muffler (7) and which enables the oil (14) accumulated in the suction muffler (7) to be transferred to the casing (2).
The compressor (1) of the present invention comprises at least one barrier (11) which is integrated to the outer surface of the suction muffler (7) around the inlet opening (8) and which at least partially surrounds the inlet opening (8).
In an embodiment of the present invention, the barrier (11) is disposed at the upper side of the opening (8). The barrier (11) prevents the oil (14) reaching the outer surface of the suction muffler (7) and trickling down under the effect of the gravity from entering the suction muffler (7) through the inlet opening (8).
In an embodiment of the present invention, the barrier (11) partially surrounds the upper part of the inlet opening (8) and has C-shaped ends extending downwards from left and right sides of the inlet opening (8). The barrier (11) enables the oil (14) reaching the outer surface of the suction muffler (7) and trickling down under the effect of the gravity to circumvents the inlet opening (8) and flow into the casing (2) without entering the suction muffler (7).
In an embodiment of the present invention, the suction muffler (7) comprises a slot (12) which opens into the inner surface thereof at the lower part of the refrigerant inlet tube (9) and wherein the oil (14) entering the suction muffler (7) together with the refrigerant is separated from the refrigerant and collected.
The oil (14) which cannot be prevented from entering the suction muffler (7) or which is mixed with the refrigerant trickles down in the suction muffler (7) under the effect of the gravity and accumulates in the slot (12). Thus, the oil (14) is enabled to be separated from the flowing refrigerant in the suction muffler (7).
In another embodiment of the present invention, the suction muffler (7) comprises at least one internal discharge hole (13) which is bored between the slot (12) and the lower surface of the refrigerant flow tube (9) and which enables the oil (14) accumulated in the slot (12) to be discharged. The oil (14) which accumulates in the slot (12) and flows towards the base of the suction muffler (7) through the inner discharge holes (13) is transferred from there to the casing (2) through the lower discharge hole (10).
In another embodiment of the present invention, the suction muffler (7) comprises a plurality of inner discharge holes (13) which are arranged along the slot (12).
In the compressor (1) of the present invention, the barriers (11) provided around the refrigerant inlet opening (8) of the suction muffler (7) prevent the oil (14) from entering the suction muffler (7). The oil (14) which cannot be prevented from entering the suction muffler (7) is collected in the slot (12) provided on the lower surface of the refrigerant flow tube (9), and removed from the suction muffler (7) by being discharged from there through the inner discharge holes (13) and the lower discharge hole (10). The oil (14) is prevented from entering the suction muffler (7) and the circulation of oil (14) in the refrigeration cycle is avoided. The abrasion and overheating of the movable mechanical components inside the casing (2) is prevented under long term operating conditions by preserving the oil (14) level in the compressor (1). The refrigeration performance is improved by preventing the transfer of oil (14) with the refrigerant to heat exchangers such as condenser and evaporator in the refrigeration cycle.

Claims

A hermetic compressor (1) which is suitable to be used in cooling devices, comprising a cylinder (3) which is arranged in a hermetic casing (2) and which enables the refrigerant to be sucked and pumped; a piston (4); a body (5) that accommodates the cylinder (3) and the piston (4); a crankshaft (6) which transfers the movement of the rotor (16) to the piston (4) and transfers the oil (14) in the casing (2) to the upper part of the body (5); a suction muffler (7) which is produced from plastic and which has a closed hollow volume; an inlet tube (15) and an inlet opening (8) which enable the refrigerant to enter the suction muffler (7); a refrigerant flow tube (9) which extends from the inlet opening (8) into the suction muffler (7); and a lower discharge hole (10) which is arranged on the base of the suction muffler (7), characterized by

- at least one barrier (11) which is integrated to the outer surface of the suction muffler (7) around the inlet opening (8) and which at least partially surrounds the inlet opening (8).
A compressor (1) as in Claim 1, characterized by the barrier (11) which is disposed at the upper side of the inlet opening (8).
A compressor as in Claim 1 or 2, characterized by the barrier (11) which partially surrounds the upper part of the inlet opening (8) and which has C-shaped ends extending downwards from left and right sides of the inlet opening (8).
A compressor (1) as in any one of the above claims, characterized by the suction muffler (7) comprising a slot (12) which opens into the inner surface thereof at the lower part of the refrigerant inlet tube (9) and wherein the oil (14) entering the suction muffler (7) together with the refrigerant is separated from the refrigerant and collected.
A compressor (1) as in Claim 4, characterized by the suction muffler (7) comprising at least one internal discharge hole (13) which is bored between the slot (12) and the lower surface of the refrigerant flow tube (9) and which enables the oil (14) accumulated in the slot (12) to be discharged.
A compressor (1) as in Claim 5, characterized by the suction muffler (7) comprising a plurality of inner discharge holes (13) which are arranged along the slot (12).