JP2007016671A - Refrigerant compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerant compressor with a low noise level, using a vibration preventing wall arranged in a sealed container for shielding the resonance of an oiling pipe propagating into oil. <P>SOLUTION: The vibration preventing wall 125 is provided on the inside bottom of the sealed container 101 to encircle the oiling pipe 118 with a predetermined distance from the oiling pipe 118. The vibration preventing wall 125 has a communication hole 128 at the lower part, with its diameter smaller than the inner diameter of the oiling pipe 118. The upper end 129 of the vibration preventing wall 125 extends to the upper side of the surface of the oil 102. Even when the resonance of the oiling pipe 118 propagates to the oil 102, it is prevented from propagating into the sealed container 101 by the vibration preventing wall 125. Thus, the refrigerant compressor is obtained with a low noise level. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a refrigerant compressor used in a freezer / refrigerator and the like.

  Conventionally, as this kind of refrigerant compressor, there is one provided with an oil supply pipe immersed in oil (see, for example, Patent Document 1).

  Hereinafter, the conventional refrigerant compressor will be described with reference to the drawings.

  4 shows a longitudinal sectional view of a conventional refrigerant compressor described in Patent Document 1, and FIG. 5 shows an enlarged cross-sectional view of a main part of the conventional refrigerant compressor described in Patent Document 1. is there.

  4 to 5, the oil 2 is stored in the sealed container 1, and the electric motor 3 and the compression element 4 driven by the electric motor 3 are stored below the electric motor 3.

  The compression element 4 includes a cylinder block 7 having a cylinder 5 and a bearing 6, and a crankshaft 10 having an eccentric portion 8 and a main shaft portion 9 and supporting the main shaft portion 9 on the bearing 6. The eccentric portion 8 of the crankshaft 10 is connected via a connecting rod 12 to a piston 11 that is reciprocally inserted into the cylinder 5. Further, the opening end of the cylinder 5 is sealed and the valve plate 14 having the discharge valve device 13 on the side opposite to the cylinder 5 is connected to the suction valve device 15 provided on the valve plate 14 at one end, and the other end is connected via the noise reduction space 16. Is provided with a suction muffler 17 that opens into the sealed container 1.

  At the lower end of the eccentric portion 8 of the crankshaft 10, an oil supply pipe 18 having one end press-fitted and fixed to the eccentric portion 8 and the other end immersed in the oil 2 is provided. The oil supply pipe 18 is made of a steel pipe and is bent into a substantially U shape so that the end immersed in the oil 2 is positioned at the rotation center of the main shaft part 9.

  The operation of the refrigerant compressor configured as described above will be described below.

  The rotation of the crankshaft 10 is transmitted to the connecting rod 12 by the electric motor 3, and the refrigerant flowing from the external cooling circuit (not shown) due to the reciprocating motion of the piston 11 is once opened in the sealed container 1 and then the suction muffler 17. Into the cylinder 5 through the intake valve device 15. The refrigerant sucked into the cylinder 5 is compressed by the piston 11 and is discharged again to an external cooling circuit (not shown) by pushing the discharge valve device 13 of the valve plate 14 open.

Further, the oil 2 in the sealed container 1 is sucked up by the oil supply pipe 18 by the centrifugal force of the oil supply pipe 18 provided at the lower end of the eccentric part 8 of the crankshaft 10 that is rotationally driven by the electric motor 3. Supplied to.
JP-A-11-303740

However, in the above conventional configuration,
When the compression element 4 compresses the refrigerant, the eccentric portion 8 of the crankshaft 10 repeats flexural deformation that is vibrated by a large intermittent load received from the connecting rod 12 during compression, but the vibration of the eccentric portion 8 is transmitted to the oil supply pipe 18. By resonating the oil supply pipe 18, a resonance noise is generated from the oil supply pipe 18.

  Furthermore, since the oil supply pipe 18 bent and formed into a substantially square shape rotates in the oil 2, the oil supply pipe 18 agitates the oil 2, and the oil 2 rotates in the sealed container 1. Since the flow collides with the components of the refrigerant compressor in the closed container 1 and the flow is disturbed, a clean vortex cannot be formed. Under such normal conditions, the refrigerant dissolved in the oil 2 continues to foam. The bubbles collide with the oil supply pipe 18 as the oil 2 is disturbed, so that the oil supply pipe is vibrated and a resonance sound is generated. Such a phenomenon is particularly noticeable in refrigerants such as hydrocarbons that have a large amount of solubility in the oil 2.

  The vibration generated by the resonance of the oil supply pipe 18 is transmitted to the sealed container 1 through the oil 2 and is diffused as noise from the sealed container 1 to the outside, which increases the noise of the refrigerant compressor. Had problems.

  An object of the present invention is to provide a refrigerant compressor with low noise by making it difficult to transmit vibration due to resonance of the oil supply pipe 18 to the sealed container 1.

  In order to solve the above-described conventional problems, the refrigerant compressor according to the present invention is provided with a vibration isolation wall that surrounds the oil supply pipe at a predetermined distance from the oil supply pipe, and is transmitted to the airtight container. It has the effect | action that the resonance sound of an oil supply pipe is interrupted | blocked by a vibration-proof wall.

  The refrigerant compressor of the present invention can provide a refrigerant compressor with low noise because the resonance noise of the oil supply pipe transmitted to the sealed container is blocked by the vibration isolation wall.

  The invention according to claim 1 is an electric motor, a compression element disposed below the electric motor and driven by the electric motor, and a hermetic seal for storing the electric motor and the compression element and storing oil. A compression shaft is connected to the crankshaft having a main shaft portion and an eccentric portion, a cylinder block having a cylinder and a bearing, a piston reciprocating in the cylinder, and the piston and the eccentric portion. A connecting rod, and an oil supply pipe fixed to the eccentric part and having one end immersed in the oil, and a vibration-proof wall surrounding the oil supply pipe at a predetermined distance from the oil supply pipe is provided at the inner bottom of the sealed container. With the arrangement, the resonance noise of the oil supply pipe 18 transmitted to the sealed container is blocked by the vibration isolation wall, so that a refrigerant compressor with low noise can be provided.

  According to a second aspect of the present invention, in addition to the first aspect, the upper end of the vibration isolation wall extends upward from the surface of the oil and a communication hole having a diameter smaller than the inner diameter of the oil supply pipe is provided in the vibration isolation wall. Resonance from the oil supply pipe while ensuring by guiding the oil to each sliding part of the compression element supplied by the oil supply pipe to the inside of the vibration isolation wall through the communication hole drilled in the vibration isolation wall Since the sound is blocked to the oil surface by the vibration-proof wall, a refrigerant compressor with lower noise can be provided.

  In addition to the invention described in claim 1 or 2, the invention described in claim 3 is the one in which the anti-vibration wall is formed by a damping member, and the resonance sound from the oil supply pipe is absorbed by the damping member. In addition to the effect of the first or second aspect, it is possible to provide a refrigerant compressor having a lower noise level.

  According to a fourth aspect of the invention, in addition to the invention according to any one of the first to third aspects, the oil supply pipe is formed of a steel pipe and has a substantially square shape, and the inner wall of the vibration isolation wall rotates. It is a body shape, and while using a highly productive and reliable oil supply pipe, the oil around the oil supply pipe creates a clean vortex, and the refrigerant bubbles in the oil are sucked smoothly toward the tip of the oil supply pipe Resonance noise of the oil supply pipe due to the collision of bubbles occurs, and in addition to the effects of claims 1 to 3, a refrigerant compressor having a lower noise level can be provided.

  In addition to the invention described in any one of claims 1 to 4, the invention described in claim 5 is one in which the refrigerant to be compressed is hydrocarbon and the oil is mineral oil or alkylbenzene, and many bubbles are generated. Nevertheless, a refrigerant compressor with a low noise level can be provided.

  Hereinafter, an embodiment of a refrigerant compressor according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of a refrigerant compressor according to Embodiment 1 of the present invention, FIG. 2 is an enlarged sectional view of a main part of the refrigerant compressor of the same embodiment, and FIG. 3 is refrigerant compression of the same embodiment. It is a plane sectional view of a machine.

  In FIGS. 1 to 3, the sealed container 101 stores oil 102 made of mineral oil at the bottom, and the inside is filled with a refrigerant 103 made of hydrocarbon such as R600a. The sealed container 101 houses an electric motor 106 including a stator 104 and a rotor 105 and a compression element 107 driven by the electric motor 106 below the electric motor 106.

  Next, the configuration of the compression element 107 will be described.

  The crankshaft 110 includes a main shaft portion 109 that is inserted into and fixed to the rotor 105 of the electric motor 106 and an eccentric portion 108. The cylinder block 114 includes a bearing 111 that rotatably supports the main shaft portion 109 of the crankshaft 110, a cylinder 113 into which a piston 115 is inserted to form a compression chamber 112, and supports the stator 104. The eccentric part 108 of the crankshaft 110 and the piston 115 are connected by a connecting rod 116.

  One end of the eccentric portion 108 is press-fitted and fixed to the lower end of the eccentric portion 108, and the other end is in the oil 102 and is located on the rotation shaft of the main shaft portion 109. A steel pipe such as a carbon steel pipe for machine structure is bent. An oil supply pipe 118 is provided that is bent into a substantially square shape. Further, the oil supply hole 119 into which the oil supply pipe 118 is press-fitted communicates with each sliding portion of the compression element 107.

  Next, the configuration of the sealed container 101 will be described.

  The hermetic container 101 is composed of a lower container 120 and an upper container 121 obtained by drawing hot rolled mild steel sheet or the like, and the lower container 120 and the upper container 121 are joined to each other by a joint 122 by electric welding. The lower container 120 includes a discharge pipe 123 and a suction pipe 124 connected to an external cooling circuit (not shown).

  The lower container 120 has a substantially cup shape, and is provided with a vibration isolation wall 125 made of polybutylene terephthalate resin or the like surrounding the oil supply pipe 118 at a predetermined distance from the oil supply pipe 118 at the inner bottom.

  The anti-vibration wall 125 is sandwiched between the bottom of the lower container 120 by a fixing bolt 126 penetrating the bottom and attached to the lower container 120 by electric welding or the like, and a fixing nut 127 screwed to the fixing bolt 126. Yes. Further, the inner surface of the vibration isolation wall 125 has a smooth rotating body centering on the rotation axis of the main shaft portion 109, and a communication hole 128 smaller than the inner diameter of the oil supply pipe 118 is formed below the vibration isolation wall 125. is doing. The upper end 129 of the vibration isolation wall 125 extends upward from the surface of the oil 102, and further extends upward from the bent portion 117 of the oil supply pipe 118.

  The operation and action of the refrigerant compressor configured as described above will be described below.

  When the electric motor 106 is energized, the rotor 105 rotates the crankshaft 110, and the piston 115 reciprocates in the cylinder 113 via the connecting rod 116, so that the refrigerant flowing from the external cooling circuit (not shown). 103 flows into the compression chamber 112 through the suction pipe 124. The refrigerant 103 that has flowed into the compression chamber 112 is then compressed by the piston 115 that reciprocates in the cylinder 113, and is discharged again from the discharge pipe 123 to the external cooling circuit (not shown).

  The oil supply pipe 118 rotates together with the crankshaft 110, but one end of the oil supply pipe 118 is press-fitted and fixed substantially at the center of the eccentric part 108, and the rotation axis of the main shaft part 109 is immersed in the oil 102. Therefore, the centrifugal force due to rotation acts on the oil 102 in the oil supply pipe 118, and this centrifugal force becomes a pump force, and the oil 102 inside the vibration isolation wall 125 is compressed through the oil supply hole 119. 107 is supplied to each sliding portion 107.

  Even if the oil level height of the oil 102 inside the vibration isolation wall 125 decreases, the oil 102 outside the vibration isolation wall 125 is continuously supplied through the communication hole 128 formed in the vibration isolation wall 125. Therefore, the oil 102 supplied to each sliding part of the compression element 107 is not interrupted.

  Here, the eccentric portion 108 of the crankshaft 110 receives the load intermittently due to the compressive load applied to the piston 115 and repeats the bending deformation, but the deflection of the eccentric portion 108 becomes vibration and vibrates the oil supply pipe 118. Thus, resonance occurs from the oil supply pipe 18.

  However, since the vibration of the oil supply pipe 118 transmitted to the closed container 101 can be blocked by the vibration isolation wall 125, the vibration transmitted from the oil supply pipe to the lower container 120 is attenuated, and the noise radiated from the closed container 101 is kept low. be able to. Here, since the anti-vibration wall 125 is made of polybutylene terephthalate resin or the like having a high damping effect, high attenuation can be obtained, and noise radiated from the sealed container 101 can be suppressed to a very low level.

  Further, since the upper end 129 of the vibration isolation wall 125 extends upward from the surface of the oil 102 and further extends upward from the bent portion 117 of the oil supply pipe 118, the oil 102 in the vibration isolation wall 125 is sealed container. The oil 102 in 101 is connected only by the communication hole 128. Since the communication hole 128 has a hole diameter smaller than the inner diameter of the oil supply pipe 118 to such an extent that insufficient oil supply does not occur in the anti-vibration wall 125, the vibration of the oil supply pipe 118 transmitted through the communication hole 128 is very small. The resonance of the oil supply pipe can be effectively blocked by the vibration isolation wall 125.

  Next, a state where the bubbles of the refrigerant 103 hit the oil supply pipe 118 will be described.

  As the operation of the refrigerant compressor is started, the inside of the sealed container 101 is depressurized, so that the refrigerant 103 dissolved in the oil 102 during the stop is foamed. The bubbles of the refrigerant 103 generated at this time draw a spiral path together with the oil 102 along with the rotation of the oil supply pipe 118, and are sucked together with the oil 102 to the tip of the oil supply pipe 118.

  At this time, if the oil 102 around the oil supply pipe 118 is disturbed and sucked together with the oil 102 to the tip of the oil supply pipe 118, these bubbles collide with the inner and outer circumferences of the oil supply pipe 118, and the oil supply pipe 118 is greatly vibrated. End up.

  However, in the present embodiment, the inner wall of the vibration isolating wall 125 has a smooth rotating body centered on the rotation axis of the main shaft portion 109 and has no protrusions or the like inside. Thus, the oil 102 inside the anti-vibration wall 125 rotates in a quiet mortar shape without being disturbed. As a result, the bubbles of the refrigerant 103 in the oil 102 approach while drawing a circle smoothly toward the tip of the oil supply pipe 118. As a result, the chance of colliding with the inner and outer surfaces of the oil supply pipe 118 is drastically reduced, and the bubbles are smooth. Since it is sucked into the oil supply pipe 118, the resonance of the oil supply pipe 118 can be drastically reduced.

  In addition, the refrigerant 103 such as hydrocarbon is highly compatible with the oil 102 such as mineral oil, and the refrigerant 103 dissolved in the oil 102 when the refrigerant compressor is stopped is abruptly foamed at the start of the refrigerant compressor. Sometimes. Further, even after such rapid foaming ends, the refrigerant in the oil 102 continuously causes some foaming during operation of the refrigerant compressor.

  In the present embodiment, the refrigerant 103 and the oil 102 that easily cause such foaming are combined. However, even if the resonance of the oil supply pipe 118 frequently occurs due to the collision between the bubbles and the oil supply pipe 118, polybutylene terephthalate resin or the like. The vibration-damping wall 125 having a high damping effect formed from the above-mentioned vibrations efficiently suppresses the vibration of the oil 102 propagating through the oil 102 and transmits the vibration to the outside of the vibration-proof wall 125. The noise level due to resonance can be reduced, and a quiet refrigerant compressor can be provided.

  Therefore, it is possible to realize a compressor with extremely low noise while using a highly productive oil supply pipe 118 in which a steel pipe such as a carbon steel pipe for machine structure is bent into a substantially U shape at a bent portion 117.

  Next, the case where the oil 102 is splashed from the surface by vigorous stirring of the oil supply pipe 118 and the oil droplets are scattered is described.

  When the oil supply pipe 118 rotates in the oil 102 during operation of the refrigerant compressor, centrifugal force also acts on the oil 102 adhering to the outer surface of the oil supply pipe 118, and in some cases, the oil droplets splashed off and separated from the oil 102 surface. Will occur. The oil droplets are usually scattered in the outer peripheral direction of the oil supply pipe 118 and collide with the sealed container 101 or the compression element 107 to become a noise source.

  However, in the refrigerant compressor according to the present embodiment, since the upper end 129 of the vibration isolating wall 125 extends to a position higher than the bent portion 117 of the oil supply pipe 118, the oil droplets splashed by the oil supply pipe 118 are not subjected to the vibration isolating wall. Even if the oil droplets are caught by the inner wall 125 and splashed, it is possible to prevent the airtight container 101 and the compression element 107 from colliding with each other, so that it is possible to provide a quiet refrigerant compressor with less such collision noise.

  In this embodiment, the soundproof wall 125 is formed of a resin such as polybutylene terephthalate resin. However, even if a rubber material such as a damping steel plate or nitrile butadiene rubber is used as the material, the same damping effect is obtained. Needless to say. Furthermore, even when a cold-rolled steel sheet that is inexpensive and has high formability is adopted as the material of the soundproof wall 125, a considerable effect can be obtained.

  As described above, the refrigerant compressor according to the present invention is applicable not only to household refrigerator-freezers that have high demands for quietness characteristics but also to applications such as freezing and refrigeration equipment in hotels and medical fields.

The longitudinal cross-sectional view of the refrigerant compressor in Embodiment 1 of this invention The principal part expanded sectional view of the refrigerant compressor in Embodiment 1 of this invention. Plan sectional drawing of the refrigerant compressor in Embodiment 1 of this invention. Vertical section of a conventional refrigerant compressor Main section enlarged sectional view of a conventional refrigerant compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Airtight container 102 Oil 106 Electric motor 107 Compression element 108 Eccentric part 109 Main shaft part 110 Crankshaft 111 Bearing 113 Cylinder 114 Cylinder block 115 Piston 116 Connecting rod 118 Oil supply pipe 125 Anti-vibration wall 128 Communication hole 129 Upper end

Claims (5)

  An electric motor; a compression element disposed below the electric motor and driven by the electric motor; and a sealed container for storing the electric motor and the compression element and storing oil, the compression element A crankshaft having a main shaft portion and an eccentric portion, a cylinder block that forms a cylinder and a bearing, a piston that reciprocates within the cylinder, a connecting rod that connects the piston and the eccentric portion, and affixed to the eccentric portion A refrigerant compressor comprising an oil supply pipe immersed at one end in the oil, and having a vibration-proof wall surrounding the oil supply pipe at a predetermined distance from the oil supply pipe at an inner bottom portion of the sealed container.   2. The refrigerant compressor according to claim 1, wherein an upper end of the vibration isolation wall extends upward from the oil surface and a communication hole having a diameter smaller than an inner diameter of the oil supply pipe is formed in the vibration isolation wall.   The refrigerant compressor according to claim 1, wherein the vibration-proof wall is formed of a vibration damping member.   The refrigerant compressor according to any one of claims 1 to 3, wherein the oil supply pipe is formed of a steel pipe and has a substantially U-shape, and the inner wall of the vibration-proof wall has a shape of a rotating body.   The refrigerant compressor according to any one of claims 1 to 4, wherein the refrigerant to be compressed is hydrocarbon, and the oil is mineral oil or alkylbenzene.

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