KR102479794B1 - Linear compressor - Google Patents

Abstract

A linear compressor according to the present invention includes a casing having a suction space; a driving unit that reciprocates the mover within the casing; A compression unit having a cylinder forming a compression chamber and a piston reciprocating by the mover to compress fluid in the compression chamber; and a muffler assembly guiding fluid from the suction space to the compression chamber, wherein the muffler assembly includes: a plurality of muffler holes forming a plurality of passages through which fluid passes inside the piston; and a muffler valve configured to open and close some of the plurality of muffler holes. According to this, the passage of the refrigerant passing through the muffler can be varied according to the operating conditions of the compressor.

Description

Linear compressor {LINEAR COMPRESSOR}

The present invention relates to a linear compressor configured to compress a fluid by linear reciprocating motion of a vibrating body.

In general, a compressor refers to a device configured to compress a working fluid such as air or refrigerant by receiving power from a power generating device such as a motor or a turbine. BACKGROUND ART Compressors are widely applied to industries in general or home appliances, in particular, to refrigerating cycles in vapor compression chambers (hereinafter referred to as 'refrigeration cycles').

Types of these compressors include a reciprocating compressor in which a compression chamber is formed between a piston and a cylinder and a piston linearly reciprocates to compress fluid, a rotary compressor to compress fluid by a roller rotating eccentrically inside a cylinder, and a spiral compressor. There is a scroll compressor in which a pair of scrolls are engaged and rotated to compress fluid.

Recently, among reciprocating compressors, a linear compressor employing a linear motor performing linear reciprocating motion without using a crankshaft has been developed. The linear compressor has the advantage of improving efficiency and having a simple structure because there is no mechanical loss associated with converting rotational motion into linear reciprocating motion.

In such a linear compressor, a cylinder is positioned inside a casing forming an airtight space to form a compression chamber, and a piston covering the compression chamber is configured to reciprocate inside the cylinder. That is, as the piston is moved to be located at the bottom dead center (BDC), the fluid in the closed space is sucked into the compression chamber, and while the piston is moved to be located at the top dead center (TDC), the fluid in the compression chamber is compressed and discharged. process is repeated.

On the other hand, the linear compressor may be equipped with a muffler device as in Patent Document 1 on the upstream side of the compression chamber in order to reduce noise. The muffler device is configured to be mounted on the piston to deliver the sucked refrigerant to the compression chamber, and serves to reduce noise by forming a complex refrigerant flow by means of a plurality of throats and spaces.

However, as the configuration of the passage inside the muffler device becomes more complicated to reduce noise, flow resistance increases in the process of transferring the refrigerant into the compression chamber, and accordingly, the efficiency of the compressor tends to decrease. That is, it can be seen that the channel structure for reducing noise and the channel structure for reducing flow resistance have conflicting aspects. In particular, design requirements related to reduction of noise and reduction of flow resistance may be different depending on the lapse of operating time or operating conditions of the compressor.

In this situation, a method of deriving a structure capable of varying the refrigerant passage formed by the muffler may be considered. Representatively, there is a need to derive a detailed method in which a refrigerant flow path can be varied in response to a change in operating conditions in an initial starting condition or a steady state operating condition of a compressor.

Patent Publication KR10-2008-0005172 A (2008.01.10. Publication)

One object of the present invention is to provide a linear compressor having a muffler structure in which a plurality of flow passages are provided and some of them are formed to be variable in an open or closed state.

Another object of the present invention is to provide a linear compressor that forms a refrigerant flow path that is advantageous for reducing noise in the initial stage of operation of the compressor and forms a refrigerant flow path that is advantageous for reducing flow path resistance when the compressor operates in a steady state.

In order to achieve the object of the present invention, a linear compressor according to the present invention includes a casing having a suction space; a driving unit that reciprocates the mover within the casing; A compression unit having a cylinder forming a compression chamber and a piston reciprocating by the mover to compress fluid in the compression chamber; and a muffler assembly guiding fluid from the suction space to the compression chamber, wherein the muffler assembly includes: a plurality of muffler holes forming a plurality of passages through which fluid passes inside the piston; and a muffler valve configured to open and close some of the plurality of muffler holes.

The muffler assembly includes a cylindrical pipe portion extending away from an inner circumferential surface of the piston, and the plurality of muffler holes include: a main hole formed at an end of the pipe portion to guide fluid into the pipe portion; and a sub-hole formed to guide fluid between the outer circumferential surface of the pipe part and the inner circumferential surface of the piston.

The muffler assembly may further include a flange portion extending in a radial direction from an outer circumferential surface of the pipe portion and supported by the piston, and the sub-hole may be formed to pass through the flange portion.

The muffler valve may include an opening/closing portion sliding on the flange portion to open or close the sub-hole; an elastic deformable part having one end positioned to be fixed to the flange part and the other end being a free end, extending in a spiral shape to surround the pipe part and supporting the opening/closing part; and a solenoid portion configured to elastically rotate the elastically deformable portion by pushing or pulling the other end of the elastically deformable portion when power is supplied.

The solenoid part may include a core positioned to be spaced apart from the other end of the elastic deformation part in a circumferential direction of the pipe part; and a valve coil wound around the core.

The core may include a first portion extending in a circumferential direction of the pipe portion; and a second part connected to the first part, extending in an axial direction of the pipe part, and winding the valve coil.

The muffler valve may include an opening/closing portion positioned to open or close some of the plurality of muffler holes; an elastic deformation unit supporting the opening/closing unit to change a position of the opening/closing unit by elastic deformation; and a solenoid unit configured to generate electromagnetic force to elastically deform the elastic deformable unit when power is supplied.

The opening/closing unit is positioned to close some of the plurality of muffler holes by power supplied to the solenoid unit when the operation of the driving unit starts, and a predetermined time elapses after the operation of the driving unit or a predetermined time of the driving unit As the power supplied to the solenoid unit is stopped when the operating frequency is reached, the closed muffler hole may be opened.

In order to achieve another object of the present invention, a linear compressor according to the present invention includes a casing having a suction space; a drive unit that drives the mover; A compression unit having a cylinder forming a compression chamber and a piston reciprocating by the mover to compress fluid in the compression chamber; and a muffler assembly for guiding fluid from the suction space to the compression chamber, wherein the muffler assembly includes: a main fluid passage spaced apart from an inner circumferential surface of the piston; a sub fluid passage formed between the main fluid passage and the inner circumferential surface of the piston; and a muffler valve controlled to open or close the sub-fluid passage, wherein the muffler valve closes the sub-fluid passage when the operation of the driving unit starts, and after a predetermined time elapses or a predetermined operating frequency is reached. It is controlled to open the sub-fluid passage.

According to the present invention constituted by the solution described above, the following effects are obtained.

In the linear compressor according to the present invention, some of the plurality of muffler holes are opened and closed by the muffler valve, so that the refrigerant suction passage can be adjusted in an optimal state for the operating conditions of the compressor in consideration of noise and flow loss. Accordingly, it is possible to control in detail the passage structure for reducing noise and improving operation efficiency, and further improving the quality and efficiency of the compressor.

In the muffler assembly of the linear compressor according to the present invention, a refrigerant flow path advantageous to noise reduction may be formed when the compressor is initially started, and a refrigerant flow path advantageous to flow loss reduction may be formed under a stabilized operating condition. Accordingly, flow energy can be prevented from being unavoidably lost in all operating conditions due to the design according to the goal of reducing the initial noise. In addition, there is an advantage in that it is possible to design a muffler structure for initial noise reduction free from the constraints of reducing flow loss.

1 is a longitudinal sectional view showing a linear compressor according to the present invention;
FIG. 2A is an enlarged view showing area A shown in FIG. 1;
Figure 2b is a conceptual view showing a state in which the muffler hole is opened in Figure 2a.
Figure 3a is a perspective view showing a portion of the muffler assembly shown in Figure 1;
3B is a conceptual view illustrating a state in which the muffler valve shown in FIG. 3A opens a muffler hole;
Figure 4a is a front view of a portion of the muffler assembly shown in Figure 3a;
4B is a front view showing a state in which the muffler valve shown in FIG. 3B opens the muffler hole;

Hereinafter, a linear compressor related to the present invention will be described in more detail with reference to the drawings.

In describing the embodiments disclosed in this specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in this specification, the detailed descriptions thereof will be omitted.

The accompanying drawings are only for easy understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the accompanying drawings, and all changes and equivalents included in the spirit and technical scope of the present invention It should be understood to include water or substitutes.

Singular expressions include plural expressions unless the context clearly dictates otherwise.

The linear compressor according to the present invention performs an operation of sucking in fluid, compressing it, and discharging the compressed fluid. The linear compressor according to the present invention may be a component of a vapor compression type refrigeration cycle, and the fluid will be described below as an example of a refrigerant circulating in the refrigeration cycle.

1 is a longitudinal cross-sectional view showing a linear compressor according to the present invention. Referring to FIG. 1 , the linear compressor 100 of the present invention includes a casing 110, a driving unit 130 and a compression unit 140.

The casing 110 may form an enclosed space. The closed space may be a suction space 101 in which the refrigerant to be compressed is sucked and filled. In order for the refrigerant to be sucked into the suction space 101, a suction port 114 may be formed in the casing 110 and a suction pipe SP may be mounted. In addition, a discharge port through which the refrigerant is discharged to the outside from a discharge space 102 described later may be formed in the casing 110 and connected to a discharge pipe DP.

In addition, a frame for supporting the drive unit 130 and the compression unit 140 may be formed inside the casing 110 . The frame may include a front frame 121 and a rear frame 122 respectively coupled to both ends of the stator 131 to be described later. In addition, a cylinder 141 to be described below may be connected to the center of the front frame 121 .

The driving unit 130 may serve to generate reciprocating motion of the linear compressor 100 according to the present invention. To this end, the drive unit 130 may include a stator 131 and a mover 132. The stator 131 may be coupled to the front and rear frames 121 and 122 . The stator 131 may include an outer core 131a disposed to surround a compression unit 140 to be described later, and an inner core 131b spaced apart from the inner side of the outer core 131a and surrounding the compression unit 140. can A mover 132 may be positioned between the outer core 131a and the inner core 131b.

Meanwhile, a winding coil 133 may be mounted on the outer core 131a, and the mover 132 may include a permanent magnet. Accordingly, when a current is applied to the driving unit 130 , magnetic flux may be formed in the stator 131 by the winding coil 133 . Electromagnetic force capable of moving the mover 132 may be generated by the interaction of the magnetic flux formed by the application of current and the magnetic flux formed by the permanent magnet.

The compression unit 140 sucks in, compresses, and discharges the refrigerant in the suction space 101 . The compression unit 140 may be located in the center of the casing 110 to the inside of the inner core 131b, and includes a cylinder 141 and a piston 142. Cylinder 141 is supported by the front frame 121 may form a compression chamber (P) therein. The cylinder 141 may have a cylindrical shape with both ends open. One end of the cylinder 141 may be closed by the discharge valve 143 and the discharge cover 144, and the other end may accommodate the piston 142.

A discharge space 102 may be formed between the discharge valve 143 and the discharge cover 144 . As shown, the compression chamber P and the discharge cover 144 may form a space separated from each other by the discharge valve 143. The discharge valve 143 is supported by an elastic member (not shown) on the discharge cover 144 and can be moved to open and close one open end of the cylinder 141 . Meanwhile, inside the casing 110, a discharge tube 111 extending to communicate the discharge port, the discharge pipe DP, and the discharge space 102 may be installed.

The piston 142 may be inserted into the other open end of the cylinder 141 to seal the compression chamber P. The piston 142 is made to be connected to the mover 132 described above, and can be reciprocated together with the mover 132. An inner core 131b and a cylinder 141 may be positioned between the mover 132 and the piston 142 . Accordingly, the mover 132 and the piston 142 may be coupled to each other by a separate moving frame 145 formed to bypass the cylinder 141 and the inner core 131b.

In the piston 142, a suction port 142a is formed to pass through one end of the compression chamber P for sealing. In this embodiment, the piston 142 is sucked into the compression chamber P between the piston 142 and the cylinder 141 by flowing the refrigerant of the suction space 101 through its internal space and passing through the suction port 142a. It can be. In addition, a suction valve 142b for opening and closing the suction port 142a may be mounted on one end surface of the piston 142 adjacent to the compression chamber P. The suction valve 142b may be operated by elastic deformation. That is, the suction valve 142b may be elastically deformed to open the suction port 142a by the pressure of the refrigerant flowing toward the compression chamber P through the suction port 142a.

Meanwhile, the driving unit 130 and the compression unit 140 described above may be supported by the support spring 150 and the resonance spring 160 . The support spring 150 serves to elastically support the driving and compression units 130 and 140 to the casing 110 . The support spring 150 may support the drive and compression units 130 and 140 at both ends in the reciprocating direction of the piston 142, and may be formed of a plate spring.

To support one end, a connection member 146 may be coupled to protrude from one end of the discharge cover 144 forming the discharge space 102 . The connection member 146 may be fixed to the central portion of the support spring 150, which is a leaf spring, and the outer circumferential portion of the support spring 150 may be fixed to the inner wall of the casing 110.

The center of the support spring 150 for supporting the other end may be fixed to the suction guide 112 formed to protrude from the suction port 114 into the casing 110, and the outer circumferential portion of the rear frame 122 It can be fixed to the cover member 123 coupled with.

The resonance spring 160 may be positioned between the rear frame 122 and the cover member 123 . As shown, the resonance spring 160 may be made of a coil spring. Both ends of the resonance spring 160 may be connected to the stationary body and the vibrating body, respectively. For example, one end of the resonance spring 160 may be connected to the moving frame 145 and the other end may be connected to the cover member 123 . Accordingly, it can be elastically deformed between the vibrating body vibrating at one end and the stationary body fixed at the other end. The natural frequency of the resonance spring 160 is designed to match the resonance frequency of the mover and the piston 142 during compressor operation, so that the reciprocating motion of the piston 142 can be amplified. However, since the stationary body is elastically supported by the casing 110 and the support spring 150, it may not be strictly fixed during operation of the compressor.

The linear compressor 100 described above operates as follows.

First, when a current is applied to the drive unit 130 , magnetic flux may be formed in the stator 131 by the current flowing through the winding coil 133 . By the electromagnetic force generated by the magnetic flux formed in the stator 131, the mover 132 having a permanent magnet can be linearly reciprocated. This electromagnetic force is generated in the direction of the piston 142 toward the top dead center (TDC) during the compression stroke, and in the direction of the piston 142 toward the bottom dead center (BDC) during the intake stroke. can occur alternately. That is, the driving unit 130 may generate thrust, which is a force pushing the mover 132 and the piston 142 in the moving direction.

The piston 142 reciprocating inside the cylinder 141 repeats the movement of increasing and decreasing the volume of the compression chamber P. When the piston 142 moves while increasing the volume of the compression chamber P, the pressure inside the compression chamber P decreases. Accordingly, the suction valve 142b mounted on the piston 142 is opened, and the refrigerant staying in the suction space 101 may be sucked into the compression chamber P. This intake stroke proceeds until the piston 142 increases the volume of the compression chamber P to the maximum and is positioned at the bottom dead center.

The movement direction of the piston 142 reaching the bottom dead center is changed to perform a compression stroke while reducing the volume of the compression chamber P. The compression stroke is performed while the piston 142 is moved to top dead center where the volume of the compression chamber P is reduced to a minimum. During the compression stroke, the pressure inside the compression chamber P increases so that the sucked refrigerant can be compressed. When the pressure in the compression chamber P reaches the preset pressure, the pressure in the compression chamber P pushes the discharge valve 143 away from the cylinder 141 to open it so that the refrigerant is discharged into the discharge space 102. .

As the suction and compression strokes of the piston 142 are repeated, the refrigerant in the suction space 101 introduced into the suction port 114 is sucked into the compression chamber P and compressed, and the discharge space 102 and the discharge tube 111 And a refrigerant flow discharged to the outside of the compressor through the discharge port may be formed.

In the above, the schematic structure and operation process of the linear compressor 100 according to the present invention has been described. Hereinafter, the muffler assembly 170 according to the present invention will be described in detail.

FIG. 2A is an enlarged view showing area A shown in FIG. 1 . 1 and 2a, the linear compressor 100 according to the present invention further includes a muffler assembly 170. In the linear compressor 100 according to the present invention, the refrigerant passing through the suction port 114 and the suction guide 112 fills the suction space 101 and flows into the compression chamber P via the muffler assembly 170. can

The muffler assembly 170 may guide the refrigerant to the compression chamber P and reduce vibration and noise caused by the reciprocating motion of the piston 142. The muffler assembly 170 extends to be inserted into the piston with an outer body 171 and an inner body 172 that are disposed parallel to the suction guide 112 and are coupled to each other and fixed to the end of the piston 142. A pipe portion 173 may be provided.

The outer and inner body parts 171 and 172 may provide passage resistance to the refrigerant introduced from the suction space 101 and form a buffer space. When the compression chamber P and the discharge space 102 are formed at one end of the piston 142, the outer and inner body parts 171 and 172 may be positioned at the other end of the piston 142. The outer and inner body parts 171 and 172 may be formed to form passages through which the refrigerant is sucked and flow, and restrict the flow of the refrigerant by their internal structures.

As shown, the outer body portion 171 may include a first passage 171a, and the inner body portion 172 may include a second passage 172a. A buffer space may be formed between the first passage 171a and the second passage 172a. When the refrigerant moves from the first passage 171a of the outer body 171 to the second passage 172a of the inner body 172, the front end of the second passage 172a close to the first passage 171a Since the diameter is formed large, the flow rate can be reduced. In addition, a shock caused by a change in flow may be alleviated by a buffer space formed on the outer circumferential sides of the first passage 171a and the second passage 172a. Accordingly, when the refrigerant passes through the outer and inner body parts 171 and 172, noise due to periodic flow change can be reduced.

In addition, the pipe part 173 provided in the muffler assembly 170 may be formed to be inserted into the inside of the piston 142 . The pipe part 173 is a passage so that the refrigerant passing through the outer and inner body parts 171 and 172 from the other end of the piston 142 can be moved to one end of the piston 142 where the compression chamber P is formed. provides That is, the refrigerant passing through the inside of the first and second passages 171a and 172a and the noise space surrounding them may flow into the compression chamber P through the pipe part 173 and the suction port 142a. there is. As shown, the pipe part 173 is disposed concentrically with the piston 142 and may extend to be spaced apart from the inner circumferential surface of the piston 142 . A space between the inner circumferential surface of the piston 142 and the pipe part 173 serves as a buffer space to reduce vibration and noise.

As described above, the muffler assembly 170 acts as a principle of stabilizing and equalizing the irregular flow by restricting the flow path of the flowing refrigerant or increasing the flow resistance. However, this action may be a factor in reducing compressor operation efficiency due to an increase in flow resistance. In addition, a typical situation in which reducing noise is an important issue is at the time of initial startup of a compressor, and in addition, the degree of demand for both noise reduction and operational efficiency increase may vary for each operating condition.

To respond to this demand, the muffler assembly 170 of the linear compressor 100 according to the present invention may further include a plurality of muffler holes 174 and muffler valves 175. FIG. 2B is a conceptual diagram showing a state in which the muffler hole 174 is opened in FIG. 2A, and the plurality of muffler holes 174 and the muffler valve 175 will be described below with reference to FIGS. 1 to 2B.

The plurality of muffler holes 174 may form a plurality of refrigerant passages passing through the inside of the piston 142 . Specifically, the plurality of muffler holes 174 are formed at the end of the pipe part 173 to guide the refrigerant into the pipe part 173, the main hole 174a, the outer circumferential surface of the pipe part 173 and the piston ( 142) may have a sub-hole 174b formed to guide a refrigerant into a space between inner circumferential surfaces.

The muffler valve 175 may be operated to open or close some of the plurality of muffler holes 174 . In this embodiment, the muffler valve 175 may be configured to selectively open and close the sub hole 174b.

When some of the plurality of muffler holes 174, particularly the sub-hole 174b, are opened and closed by the muffler valve 175, the linear compressor 100 according to the present invention can adjust the degree of noise reduction according to operating conditions. do. For example, in an operating condition in which flow inside the compressor is unstable and noise is high, as shown in FIG. Specifically, when the sub-hole 174b is closed, it may be a condition of operating at a relatively low frequency. On the other hand, under the condition that the internal flow of the compressor is generally stable, as shown in FIG. 2B, the sub-hole 174b may be opened to smoothly introduce more refrigerant into the compression chamber.

As a result, since the muffler valve 175 is varied to open and close the muffler hole 174, the refrigerant flow can be controlled in detail, and the quality and efficiency of the compressor can be further improved.

Meanwhile, FIG. 3A is a perspective view showing a part of the muffler assembly 170 shown in FIG. 1, and FIG. 3B is a conceptual view showing a state in which the muffler valve 175 shown in FIG. 3A opens the muffler hole 174. 4A is a front view showing a part of the muffler assembly 170 shown in FIG. 3A, and FIG. 4B is a front view showing a state in which the muffler valve 175 shown in FIG. 3B opens the muffler hole 174. Referring to the drawings, a specific embodiment of the muffler hole 174 and the muffler valve 175 will be described.

The muffler assembly 170 may further include a flange portion 176 . The flange portion 176 may be formed to protrude and extend in a radial direction from an outer circumferential surface of an end side of the pipe portion 173 where the main hole 174a is located. The flange portion 176 may be supported by the piston 142 by being coupled to an inner circumferential surface or an end surface of the piston 142 .

Also, the sub-hole 174b described above may be formed to pass through the flange portion 176 . As shown, a plurality of sub-holes 174b may be formed spaced apart at predetermined intervals along the circumferential direction of the flange portion 176 to surround the main hole 174a. This embodiment shows an example in which four sub-holes 174b are formed at intervals of 90 degrees.

Meanwhile, in the present invention, the muffler valve 175 may include an opening/closing portion 175a, an elastic deformation portion 175b, and a solenoid portion 175c. The opening/closing portion 175a may open or close the sub-hole 174b while sliding on the flange portion 176 . The opening/closing portion 175a may be formed in a size capable of overlapping the sub-hole 174b on one side of the flange portion 176, and may be configured to be movable and operated to open or close the sub-hole 174b. .

The elastic deformation part 175b may serve to provide force for moving the opening/closing part 175a. In this embodiment, the elastically deformable portion 175b extends in a spiral shape, and one end thereof may be positioned to be fixed to the flange portion 176 and the other end may be formed as a free end 175b1. As shown, one end of the elastically deformable portion 175b may be fixed to a support portion 176a protruding from one side of the flange portion 176 . In addition, the elastic deformation part 175b may support the opening/closing part 175a and provide elastic force to the opening/closing part 175a. A plurality of opening/closing parts 175a may be formed to protrude from the spiral elastic deformation part 175b toward the center so as to cover the plurality of sub-holes 174b. The elastic deformation part 175b may be entirely made of a magnetic material such as metal, or the other end formed as the free end 175b1 may be made of a magnetic material.

In the muffler valve 175 of the present invention, the helical elastic deformation part 175b may move the opening/closing part 175a by a rotational motion. That is, the elastic deformation part 175b may open or close the sub hole 174b by rotating the opening/closing part 175a along the circumference of the pipe part 173 .

At this time, the rotational force of the elastic deformation part 175b in one direction may be due to the elastic force of the member itself, and the rotational force in the other direction may be due to the electromagnetic force of the solenoid part 175c. That is, the solenoid part 175c may push or pull the other end of the elastically deformable part 175b to rotate the elastically deformable part 175b around the pipe part 173 when power is supplied.

The solenoid part 175c may include a core 175c1 and a valve coil 175c2. The core 175c1 is a component serving as an electromagnet body, and is spaced apart from the other end (free end 175b1) of the elastically deformable portion 175b in the circumferential direction of the pipe portion 173, or the elastically deformable portion 175b. It may be made to be in contact with the other end and each other. That is, according to the electromagnetic force formed in the core 175c1, the free ends 175b1 of the elastically deformable portion 175b may come into contact with each other by attraction or be spaced apart from each other by repulsive force.

The core 175c1 may include first to third parts 175c11, 175c12, and 175c13. The first part 175c11 may extend in the circumferential direction of the pipe part 173 and come into contact with the free end 175b1 of the elastically deformable part 175b. The second part 175c12 may be connected to the first part 175c11 and extend in the axial direction of the pipe part 173, and the valve coil 175c2 may be wound. In addition, one side of the third portion 175c13 may be connected to the second portion 175c12 and the other side may be coupled to and supported by an inner circumferential surface of the support portion 176a of the flange portion 176 .

On the other hand, as mentioned above, the flow is relatively unstable and the need for noise reduction is high at the beginning of the compressor operation, and the need for noise reduction is relatively small when the compressor is operating in a normal state, and it is important to reduce the flow resistance. can be an element. Therefore, it is preferable to close the sub-hole 174b when the compressor starts and open the sub-hole 174b when the compressor operates normally.

Further, in the linear compressor 100 according to the present invention, a condition in which power is supplied to the solenoid unit 175c may be a state in which the sub hole 174b is closed. That is, when the compressor starts, power is supplied to the solenoid part 175c to move the opening/closing part 175a to close the sub hole 174b.

For example, the sub hole 174b may be closed as shown in FIGS. 3A and 4A under a compressor starting condition. As shown, the closed state of the sub-hole 174b may be a state in which power is supplied to the solenoid part 175c and the other end of the elastically deformable part 175b is pushed by a repulsive force. In order to realize this condition, the free end 175b1 of the elastic deformation part 175b may be configured to distribute magnetic poles of the same polarity as the solenoid part 175c when power is supplied.

Conversely, the state shown in FIGS. 3B and 4B may be a steady state operating condition of the compressor. In the illustrated state, the supply of power to the solenoid part 175c is stopped and the elastic deformation part 175b may return to contact the core 175c1 of the solenoid part 175c with its other end by restoring force.

In addition, whether the sub hole 174b is closed or opened may be determined and controlled by time or operating frequency. For example, when the operation of the driving unit 130 starts, in a state where the sub-hole 174b is closed by the power supplied to the solenoid unit 175c, after the operation of the driving unit 130, a predetermined time elapses or Power supply can be stopped by detecting the arrival of the set operating frequency.

By the above control, a refrigerant flow path advantageous to noise reduction may be formed when the linear compressor 100 according to the present invention is initially started, and a refrigerant flow path advantageous to flow loss reduction may be formed under a stabilized operating condition. Accordingly, flow energy can be prevented from being unavoidably lost in all operating conditions due to the design according to the goal of reducing the initial noise. In addition, there is an advantage in that it is possible to design a muffler structure for initial noise reduction free from the constraints of reducing flow loss.

Furthermore, in the linear compressor 100 according to the present invention, the operation time of the unsteady state including the initial operation of the drive unit 130 occupies the total operation time rather than the operation time of the steady state in which the operation is stable. proportion may be small. Therefore, by setting the state in which power is supplied to the solenoid unit 175c to an abnormal state, power consumption due to opening and closing of the muffler can be reduced.

Meanwhile, the variable muffler configuration according to the present invention has been described above based on the structure in which a plurality of muffler holes 174 are formed in the muffler assembly 170 and some of them are opened or closed. However, a variable muffler configuration according to the present invention can be implemented by changing the configuration of the passage even if the hole is not opened or closed in the muffler assembly 170 .

That is, the muffler assembly 170 is formed in parallel with the main fluid passage 170a spaced apart from the inner circumferential surface of the piston 142 and the main fluid passage 170a, and between the inner circumferential surface of the piston 142 and the main fluid passage 170a. It may include a sub-fluid passage (170b) formed in. In addition, the muffler assembly 170 may further include a muffler valve 175 controlled to open or close the sub-fluid passage 170b, which has a large effect on noise reduction.

In this case, the muffler valve 175 may be controlled to close the sub fluid passage 170b when the operation of the driving unit 130 starts and open the sub fluid passage 170b in a normal state thereafter. The criterion for switching the sub-fluid flow passage 170b from the closed state to the open state may be a lapse of a preset time after operating the driving unit 130 or reaching a preset operating frequency after operating the driving unit 130 .

What has been described above is only an embodiment for implementing the linear compressor according to the present invention, and the present invention is not limited to the above embodiment, and as claimed in the following claims, within the scope of not departing from the gist of the present invention Anyone skilled in the art to which the present invention pertains will say that the technical spirit of the present invention exists to the extent that various changes can be made.

100: linear compressor 101: suction space
102: discharge space 110: casing
111: discharge tube 112: suction guide
114: inlet 121: front frame
122: rear frame 123: cover member
130: drive unit 131: stator
131a: outer core 131b: inner core
132: mover 133: winding coil
140: compression unit 141: cylinder
142: piston 142a: suction port
142b: intake valve 143: discharge valve
144: discharge cover 145: moving frame
146: connecting member 150: support spring
160: resonance spring 170: muffler assembly
170a: main fluid passage 170b: sub fluid passage
171: outer body 172: inner body
173: pipe part 174: muffler hole
174a: Main Hall 174b: Sub Hall
175: muffler valve 175a: opening and closing part
175b: elastic deformation part 175c: solenoid part
176: flange portion 176a: support portion

Claims (11)

A casing having a suction space;
A driving unit having a mover reciprocating in the casing, a stator and a winding coil for driving the mover;
a compression unit having a cylinder accommodated inside the casing and forming a compression chamber, and a piston reciprocated by the mover to compress fluid in the compression chamber; and
A muffler assembly coupled to the piston and configured to guide fluid from the suction space to the compression chamber;
The muffler assembly,
a plurality of muffler holes forming a plurality of passages through which fluid passes through the inside of the piston; and
A linear compressor having a muffler valve configured to open and close some of the plurality of muffler holes. According to claim 1,
The muffler assembly has a cylindrical pipe part extending away from the inner circumferential surface of the piston,
The plurality of muffler holes,
a main hole formed at an end of the pipe unit to guide the fluid into the pipe unit; and
A linear compressor having a sub-hole formed to guide fluid between an outer circumferential surface of the pipe part and an inner circumferential surface of the piston. According to claim 2,
The muffler assembly further includes a flange portion extending in a radial direction from an outer circumferential surface of the pipe portion and supported by the piston,
The linear compressor, characterized in that the sub-hole is formed to pass through the flange portion. According to claim 3,
The muffler valve,
an opening/closing portion sliding on the flange portion to open or close the sub-hole;
an elastic deformable part having one end positioned to be fixed to the flange part and the other end being a free end, extending in a spiral shape to surround the pipe part and supporting the opening/closing part; and
A linear compressor having a solenoid portion configured to elastically rotate the elastically deformable portion by pushing or pulling the other end of the elastically deformable portion when power is supplied. According to claim 4,
The solenoid part,
a core positioned to be spaced apart from the other end of the elastically deformable part in a circumferential direction of the pipe part; and
A linear compressor having a valve coil wound around the core. According to claim 5,
the core,
a first part extending in a circumferential direction of the pipe part; and
A linear compressor having a second part connected to the first part, extending in an axial direction of the pipe part, and winding the valve coil. According to claim 1,
The muffler valve,
an opening/closing portion positioned to open or close some of the plurality of muffler holes;
an elastic deformation unit supporting the opening/closing unit to change a position of the opening/closing unit by elastic deformation; and
A linear compressor having a solenoid unit for forming an electromagnetic force to elastically deform the elastic deformable unit when power is supplied. According to claim 7,
The opening part,
Positioned to close some of the plurality of muffler holes by power supplied to the solenoid unit when the operation of the driving unit starts,
The linear compressor, characterized in that positioned to open the closed muffler hole as power supplied to the solenoid unit is stopped when a predetermined time elapses after operation of the driving unit or when a predetermined operating frequency of the driving unit is reached. A casing having a suction space;
A drive unit having a mover reciprocating in the casing, a stator for driving the mover, and a winding coil;
a compression unit having a cylinder accommodated inside the casing and forming a compression chamber, and a piston reciprocated by the mover to compress fluid in the compression chamber; and
A muffler assembly coupled to the piston and configured to guide fluid from the suction space to the compression chamber;
The muffler assembly,
a main fluid passage spaced apart from an inner circumferential surface of the piston;
a sub fluid passage formed in parallel with the main fluid passage between the main fluid passage and an inner circumferential surface of the piston; and
A linear compressor having a muffler valve controlled to open or close the sub-fluid passage. According to claim 9,
The muffler valve,
closing the sub-fluid passage when the driving unit starts to operate;
The linear compressor, characterized in that controlled to open the sub-fluid passage after a predetermined time has elapsed. According to claim 9,
The muffler valve,
closing the sub-fluid passage when the driving unit starts to operate;
The linear compressor, characterized in that controlled to open the sub-fluid passage when the drive unit reaches a predetermined operating frequency.

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