KR20220105468A - Method for controlling linear compressor and refrigerator including linear compressor - Google Patents

Abstract

The present specification relates to a control method of a linear compressor and a refrigerator including the linear compressor. According to an embodiment of the present specification, a compressor controller for controlling the driving of the compressor measures the temperature around the compressor in the process of controlling the driving of the compressor. The compressor controller compares the temperature around the compressor with a predetermined reference range and adjusts the stroke value of the compressor according to the comparison result. In one embodiment of the present specification, as the temperature around the compressor decreases, the phenomenon in which the levitation force of a piston decreases is improved by increasing the lowest stroke value of the compressor. Therefore, even if the temperature around the compressor decreases, the friction between the piston and a cylinder decreases or does not occur, reducing the possibility of compressor failure.

Description

The control method of a linear compressor, and the refrigerator including a linear compressor TECHNICAL FIELD

The present specification relates to a method for controlling a linear compressor and a refrigerator including the linear compressor.

A compressor is a mechanical device that increases pressure by compressing a refrigerant or various other working gases, and is used in home appliances such as refrigerators and air conditioners.

Compressors may be classified into several types according to internal structures and operating principles. In the compressor, a compression space for suction and discharge of working gas is formed between a piston and a cylinder, and a reciprocating compressor that compresses a refrigerant while a piston moves linearly and reciprocates inside the cylinder, an eccentrically rotating roller and a cylinder A compression space for suction and discharge of the working gas is formed between the rotary compressor, which compresses the refrigerant while the roller rotates eccentrically along the inner wall of the cylinder, between the orbiting scroll and the fixed scroll It may be classified as a scroll compressor in which a compression space in which the working gas is sucked and discharged is formed, and the orbiting scroll rotates along the fixed scroll to compress the refrigerant.

Recently, among reciprocating compressors, a linear compressor in which a piston is directly connected to a mover of a linear motor and the piston is reciprocated by a linear motion of the motor is widely used. In a linear compressor, the refrigerant is sucked in and compressed by a piston reciprocating linear motion inside the cylinder by a linear motor, and then discharged to the outside.

The structure of a reciprocating compressor (linear compressor) is disclosed in the prior literature (Korean Patent Publication No. 10-1332556).

More specifically, in the prior literature, a fluid bearing is formed between the piston and the cylinder by bypassing a part of the refrigerant between the compressor, that is, the piston and the cylinder to compensate for the disadvantage of the compressor in which the piston and the cylinder are lubricated by a lubricant such as oil. A fluid bearing type or an oilless bearing type linear compressor is disclosed.

In the fluid bearing type linear compressor disclosed in the prior literature, when the refrigerant compressed by the piston is discharged, a part of the discharged refrigerant (hereinafter, the bearing refrigerant) flows into the cylinder. The bearing refrigerant flowing into the cylinder provides levitation force to the piston. As the piston floats inside the cylinder by the levitation force provided by the bearing refrigerant, the piston and the cylinder do not rub against each other.

However, according to the prior art, when the ambient temperature of the linear compressor decreases, the cooling power of the linear compressor decreases and the amount of the bearing refrigerant flowing into the cylinder decreases. When the amount of bearing refrigerant flowing into the cylinder decreases, the levitation force of the piston weakens and friction occurs between the piston and the cylinder during the reciprocating motion. As a result, wear may occur outside the piston or inside the cylinder. Such wear of the piston or cylinder may cause deterioration of the performance of the compressor or failure of the compressor.

An object of the present specification is to increase the levitation force of the piston by the bearing refrigerant flowing into the cylinder when the ambient temperature of the linear compressor is lowered, thereby reducing friction between the piston and the cylinder and preventing wear of the piston or cylinder. And to provide a refrigerator including a linear compressor.

In addition, an object of the present specification is to prevent deterioration of the performance of the linear compressor by preventing abrasion of the piston or cylinder when the ambient temperature is lowered, and to reduce the possibility of malfunction of the linear compressor and the refrigerator.

The purpose of the present specification is not limited to the above-mentioned purpose, and other objects and advantages of the present specification not mentioned will be more clearly understood by the examples of the present specification described below. In addition, the objects and advantages of the present specification can be realized by the elements and combinations thereof recited in the claims.

In one embodiment of the present specification, the compressor controller for controlling the driving of the compressor measures the temperature around the compressor while controlling the driving of the compressor. The compressor controller compares the temperature around the compressor with a predetermined reference range, and adjusts the stroke value of the compressor according to the comparison result.

More specifically, in one embodiment of the present specification, the compressor controller sets the lowest stroke value of the compressor to a value higher than the basic stroke value when the ambient temperature of the compressor decreases. In one embodiment of the present specification, the compressor controller controls the stroke value of the compressor not to be lower than the lowest stroke value when the compressor is driven. Therefore, when the minimum stroke value of the compressor becomes higher than the basic stroke value, the stroke value of the compressor increases and the torque of the piston increases.

When the torque of the piston increases, the refrigerant discharged to the outside after being compressed by the piston, that is, the pressure of the discharged refrigerant increases. When the pressure of the discharge refrigerant increases, the amount of the bearing refrigerant flowing into the cylinder during the operation of the compressor increases. As the amount of bearing refrigerant increases, the levitation force of the piston increases, thus reducing the friction between the piston and the cylinder.

As such, in one embodiment of the present specification, as the ambient temperature of the compressor decreases, the phenomenon in which the levitation force of the piston decreases by increasing the minimum stroke value of the compressor is improved. Accordingly, even if the ambient temperature of the compressor is reduced, friction between the piston and the cylinder is reduced or not generated, thereby reducing the possibility of malfunction of the compressor.

A control method of a linear compressor according to an embodiment of the present specification includes receiving an ambient temperature value of the compressor, comparing the ambient temperature value with a predetermined reference temperature range, and comparing the ambient temperature value with the reference temperature range. and adjusting the stroke value of the compressor according to the comparison result.

In one embodiment of the present specification, the adjusting the stroke value of the compressor includes adjusting the lowest stroke value of the compressor to a value corresponding to a reference temperature range to which the ambient temperature value belongs.

In an embodiment of the present specification, the lowest stroke value is set to increase as the ambient temperature value decreases.

In one embodiment of the present specification, the step of adjusting the stroke value of the compressor includes: if the ambient temperature value is equal to or greater than a predetermined reference temperature value, setting the lowest stroke value of the compressor as a predetermined basic stroke value; and setting the lowest stroke value to a value higher than the basic stroke value if the value is less than the reference temperature value.

In one embodiment of the present specification, the adjusting the stroke value of the compressor includes setting the stroke value of the compressor to increase as the ambient temperature value decreases.

In addition, the refrigerator according to an embodiment of the present specification includes a cabinet having a storage compartment formed therein, a compressor that compresses refrigerant for supplying cold air to the storage compartment and is disposed inside a machine room formed inside the cabinet, and an ambient temperature of the compressor It includes a temperature sensor for measuring, and a compressor controller for controlling the operation of the compressor.

In one embodiment of the present specification, the compressor controller receives an ambient temperature value measured by the temperature sensor, compares the ambient temperature value with a predetermined reference temperature range, and compares the ambient temperature value with the reference temperature range. The stroke value of the compressor is adjusted according to the comparison result.

In one embodiment of the present specification, the compressor controller adjusts the lowest stroke value of the compressor to a value corresponding to a reference temperature range to which the ambient temperature value belongs.

In an embodiment of the present specification, the lowest stroke value is set to increase as the ambient temperature value decreases.

In one embodiment of the present specification, the compressor controller sets the lowest stroke value of the compressor to a predetermined basic stroke value when the ambient temperature value is equal to or greater than a predetermined reference temperature value, and the ambient temperature value is less than the reference temperature value , the lowest stroke value is set to a value higher than the basic stroke value.

In one embodiment of the present specification, the compressor controller sets the stroke value of the compressor to increase as the ambient temperature value decreases.

According to the embodiment of the present specification, when the ambient temperature of the linear compressor is lowered, the levitation force of the piston due to the bearing refrigerant flowing into the cylinder is not reduced by increasing the stroke value of the piston. Accordingly, since friction between the piston and the cylinder does not occur in the process of the piston reciprocating inside the cylinder, wear of the piston or the cylinder can be prevented.

In addition, according to the embodiment of the present specification, since wear of the piston or cylinder is prevented when the ambient temperature of the linear compressor is lowered, deterioration of the performance of the linear compressor is prevented and the possibility of malfunction of the linear compressor and the refrigerator is reduced.

1 is a perspective view of a refrigerator according to an embodiment of the present specification.
2 is a view illustrating an external appearance of a linear compressor according to an embodiment of the present specification.
3 is a view illustrating a state in which a shell and a shell cover of a linear compressor according to an embodiment of the present specification are disassembled.
4 is an exploded view illustrating a linear compressor according to an embodiment of the present specification.
FIG. 5 is a view showing a cross-section taken along V-V' of FIG. 2 .
6 is a block diagram illustrating a configuration of a refrigerator according to an embodiment of the present specification.
7 is a flowchart illustrating a control method of a linear compressor according to an embodiment of the present specification.
8 is a flowchart illustrating a control method of a linear compressor according to another embodiment of the present specification.
9 is a flowchart illustrating a control method of a linear compressor according to another embodiment of the present specification.
10 is a graph showing changes in the pressure of the refrigerant sucked into the linear compressor and the pressure of the refrigerant discharged from the linear compressor according to the driving time of the linear compressor.
11 is a graph showing a change in frictional force between a piston and a cylinder according to a difference value between the pressure of the refrigerant sucked into the linear compressor and the pressure of the refrigerant discharged from the linear compressor.
12 and 13 are graphs illustrating a change in the magnitude of a load received by a cylinder according to a driving time of the linear compressor.

The above-described objects, features, and advantages will be described below in detail with reference to the accompanying drawings, and accordingly, those of ordinary skill in the art to which this specification belongs will be able to easily practice the embodiments of the present specification. In the description of the present specification, if it is determined that a detailed description of a known technology related to the present specification may unnecessarily obscure the subject matter of the present specification, the detailed description will be omitted. Hereinafter, preferred embodiments of the present specification will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals indicate the same or similar components.

1 is a perspective view of a refrigerator according to an embodiment of the present specification.

1 , a refrigerator 1 according to an embodiment of the present specification includes a cabinet 2 forming an exterior and at least one refrigerator door 3 coupled to the cabinet 2 .

At least one storage compartment 4 is provided inside the cabinet 2 . The refrigerator door 3 may be rotatably or slidably connected to the front surface of the cabinet 2 to open and close the storage compartment 4 . The storage compartment 4 includes at least one of a refrigerating compartment and a freezing compartment, and each storage compartment may be partitioned by a silver partition wall.

In addition, a machine room 5 in which the compressor 10 is disposed is provided inside the cabinet 2 . As shown in FIG. 1 , the machine room 5 may be disposed at the lower rear side of the cabinet 2 . However, the arrangement of the machine room 5 and the compressor 10 shown in FIG. 1 is merely exemplary, and the machine room 5 and the compressor 10 may be disposed at different positions according to embodiments.

In order to maintain the storage chamber at a low temperature, cold air must be supplied into the storage chamber. When the compressor 10 is driven to supply cold air, the compressor 10 sucks and compresses a gaseous refrigerant, and the compressed refrigerant of high temperature/high pressure is liquefied through the condenser. Refrigerant from the condenser goes through the evaporator and heat exchanges to lower the temperature of the air around the evaporator to generate cold air. The refrigerant passing through the evaporator is supplied to the compressor 10 again to circulate the refrigerant. This process is repeated and the refrigerant is circulated, so that cold air is supplied to the inside of the storage chamber.

As will be described later, the compressor 10 is driven or the compressor 10 is stopped by the compressor controller electrically connected to the compressor 10 . Also, as will be described later, the compressor 10 according to an embodiment of the present specification is a linear compressor of a fluid bearing type or an oilless bearing type.

2 is a view showing an external appearance of a linear compressor according to an embodiment of the present specification, and FIG. 3 is a view showing a state in which a shell and a shell cover of the linear compressor according to an embodiment of the present specification are disassembled.

2 and 3 , the compressor 10 according to an embodiment of the present specification includes a shell 101 and shell covers 102 and 103 coupled to the shell 101 . In a broad sense, the shell covers 102 , 103 may be understood as one component of the shell 101 .

A leg 50 may be coupled to a lower side of the shell 101 . The leg 50 may be coupled to the base of the product on which the compressor 10 is installed. In other words, the leg 50 may be coupled to the machine room 5 of the refrigerator 1 described above.

The shell 101 has a cylindrical shape and may be disposed in a transverse direction or an axial direction. For example, in the embodiment shown in FIG. 2 the shell 101 is arranged in a transverse direction.

A terminal 108 may be installed on the outer surface of the shell 101 . The terminal 108 is a means for electrically connecting an external power source and the motor assembly 140 (refer to FIG. 4 ), and may be connected to a lead wire of the coil 141c (refer to FIG. 4 ).

A bracket 109 is installed on the outside of the terminal 108 . Bracket 109 includes a plurality of brackets surrounding terminal 108 . The bracket 109 protects the terminal 108 from external impact.

Both sides of the shell 101 are configured to be opened. Shell covers 102 and 103 may be coupled to both sides of the opened shell 101 . More specifically, the shell covers 102 and 103 include a first shell cover 102 coupled to an open one side of the shell 101 and a second shell cover 103 coupled to the other open side of the shell 101 . ) is included. The inner space of the shell 101 may be sealed by the shell covers 102 and 103 .

In the embodiment shown in FIG. 2 , the first shell cover 102 is disposed on the right side of the compressor 10 , and the second shell cover 103 is disposed on the left side of the compressor 10 . Accordingly, the first shell cover 102 and the second shell cover 103 are disposed to face each other.

In addition, the compressor 10 is connected to the shell 101 or the shell cover 102, 103 and includes a plurality of pipes 104, 105, 106 for sucking or discharging the refrigerant.

The plurality of pipes 104 , 105 , 106 includes a suction pipe 104 for sucking the refrigerant into the compressor 10 , a discharge pipe 105 for discharging the refrigerant compressed in the compressor 10 , and a compressor for replenishing the refrigerant. A process pipe 106 for injecting refrigerant into 10 is included.

The suction pipe 104 may be coupled to the first shell cover 102 . The refrigerant is sucked into the compressor 10 along the axial direction through the suction pipe 104 .

The discharge pipe 105 may be coupled to the outer circumferential surface of the shell 101 . The refrigerant sucked through the suction pipe 104 is compressed while flowing in the axial direction. The compressed refrigerant is discharged to the outside of the compressor 10 through the discharge pipe 105 . The discharge pipe 105 may be disposed to be more adjacent to the second shell cover 103 than the first shell cover 102 .

The process pipe 106 may be coupled to the outer circumferential surface of the shell 101 . The operator may inject the refrigerant into the compressor 10 through the process pipe 106 .

The process pipe 106 may be coupled to the shell 101 at a different height than the discharge pipe 105 to avoid interference with the discharge pipe 105 . Here, the height of the pipe means the distance from the leg 50 to the pipe measured in the vertical (or radial) direction. Since the discharge pipe 105 and the process pipe 106 are coupled to the outer circumferential surface of the shell 101 at different heights, work convenience can be promoted.

At least a portion of the second shell cover 103 may be adjacent to the inner circumferential surface of the shell 101 corresponding to the point at which the process pipe 106 is coupled. In other words, at least a portion of the second shell cover 103 may act as a resistance of the refrigerant injected through the process pipe 106 .

Accordingly, from the viewpoint of the flow path of the refrigerant, the size of the flow path of the refrigerant introduced through the process pipe 106 is reduced by the second shell cover 103 while entering the inner space of the shell 101 and the second shell cover 103 . increases again as it passes through As the refrigerant passes through the process pipe 106 , the pressure of the refrigerant decreases, so that the refrigerant is vaporized.

The inner surface of the first shell cover 102 is provided with a cover support portion (102a). A second support device 185 to be described later may be coupled to the cover support portion 102a. The cover support portion 102a and the second support device 185 are means for supporting the main body of the compressor 10 . Here, the main body of the compressor 10 refers to a component provided in the shell 101 . For example, the main body of the compressor 10 includes a driving part that reciprocates back and forth and a support part for supporting the driving part.

The driving part of the compressor 10 includes a piston 130, a magnet frame 138, a permanent magnet 146, a supporter 137, and a suction muffler 150 to be described later. And the support part is a resonance spring (to be described later) 176a and 176b), a rear cover 170 , a stator cover 149 , a first support device 165 , and a second support device 185 .

A stopper 102b is provided on the inner surface of the first shell cover 102 . The stopper 102b prevents the main body of the compressor, in particular, the motor assembly 140 from being damaged by colliding with the shell 101 due to vibration or shock generated during transportation of the compressor 10 . The stopper 102b is disposed adjacent to the rear cover 170 to be described later. When vibration occurs in the compressor 10 , the rear cover 170 interferes with the stopper 102b, thereby preventing the shock from being transmitted to the motor assembly 140 .

The inner peripheral surface of the shell 101 is provided with a spring fastening portion (101a). For example, the spring fastening portion 101a may be disposed at a position adjacent to the second shell cover 103 . The spring fastening portion 101a may be coupled to a first support spring 166 of a first support device 165 to be described later. As the spring fastening portion 101a and the first supporting device 165 are coupled, the main body of the compressor 10 may be stably supported inside the shell 101 .

4 is an exploded view illustrating a linear compressor according to an embodiment of the present specification, and FIG. 5 is a view illustrating a cross-section taken along V-V′ of FIG. 2 .

4 and 5 , the compressor 10 according to an embodiment of the present specification applies a driving force to the cylinder 120 , the piston 130 reciprocating linearly within the cylinder 120 , and the piston 130 . It includes a motor assembly 140 to provide.

In addition, the compressor 10 is connected to the piston 130 and includes a suction muffler 150 for reducing noise generated from the refrigerant sucked through the suction pipe 104 . The refrigerant sucked through the suction pipe 104 flows into the piston 130 through the suction muffler 150 . In the process of the refrigerant passing through the suction muffler 150 , the flow noise of the refrigerant is reduced.

The suction muffler 150 includes a plurality of mufflers 151 , 152 , 153 . The plurality of mufflers 151 , 152 , and 153 include a first muffler 151 , a second muffler 152 , and a third muffler 153 coupled to each other.

The first muffler 151 is disposed inside the piston 130 , and the second muffler 152 is coupled to the rear side of the first muffler 151 . In addition, the third muffler 153 accommodates the second muffler 152 therein, and may extend to the rear of the first muffler 151 . From the viewpoint of the flow direction of the refrigerant, the refrigerant sucked through the suction pipe 104 sequentially passes through the third muffler 153 , the second muffler 152 , and the first muffler 151 . In this process, the flow noise of the refrigerant is reduced.

A muffler filter (not shown) may be disposed at the interface where the first muffler 151 and the second muffler 152 are coupled. The muffler filter may have a circular shape, and the outer periphery of the muffler filter may be supported between the first and second mufflers 151 and 152 .

Hereinafter, “axial direction” refers to a direction in which the piston 130 reciprocates, that is, a horizontal direction in FIG. 5 . Among the "axial directions", the direction from the suction pipe 104 to the compression space P, that is, the direction in which the refrigerant flows, is referred to as "front", and the opposite direction is defined as "rear". For example, when the piston 130 moves forward, the compression space P may be compressed.

In addition, hereinafter, "radial direction" is a direction perpendicular to the direction in which the piston 130 reciprocates, and means a vertical direction in FIG. 5 .

The piston 130 includes a cylindrical piston body 131 and a piston flange 132 extending radially from the piston body 131 . The piston body 131 reciprocates inside the cylinder 120 , and the piston flange 132 reciprocates outside the cylinder 120 .

In addition, the piston 130 includes a suction hole 133 through which the refrigerant flows and a suction valve 135 for opening and closing the suction hole 133 . The suction hole 133 is formed in the front part of the piston body 131 .

In addition, the piston 130 further includes a valve fastening member 134 for fastening the suction valve 135 to the piston 130 . The valve fastening member 134 may be coupled to the front portion of the piston body 131 through the suction valve 135 .

The cylinder 120 houses the piston 130 . The cylinder 120 may accommodate the first muffler 151 and at least a portion of the piston body 131 . A compression space P in which the refrigerant is compressed by the piston 130 is formed in the cylinder 120 .

Also, the compressor 10 includes a discharge cover 160 and discharge valve assemblies 161 and 163 . The discharge cover 160 is installed in front of the compression space (P) to form a discharge space (160a) in which the refrigerant discharged from the compression space (P) flows. The discharge space 160a includes a plurality of space portions partitioned by the inner wall of the discharge cover 160 . The plurality of space portions may be disposed in the front-rear direction and may communicate with each other.

The discharge valve assemblies 161 and 163 are coupled to the discharge cover 160 and selectively discharge the refrigerant compressed in the compression space P. In the discharge valve assemblies 161 and 163, a discharge valve 161 and the discharge valve 161 that are opened when the pressure in the compression space P is equal to or greater than the discharge pressure to introduce a refrigerant into the discharge space 160a; and a spring assembly 163 provided between the discharge cover 160 and providing an elastic force in the axial direction is included.

The spring assembly 163 includes a valve spring 163a and a spring support portion 163b for supporting the valve spring 163a to the discharge cover 160 . The valve spring 163a includes a leaf spring. The spring support part 163b may be injection-molded integrally with the valve spring 163a by an injection process.

The discharge valve 161 is coupled to the valve spring 163a, and a rear or rear surface of the discharge valve 161 is disposed to support the front surface of the cylinder 120 . When the discharge valve 161 is supported on the front surface of the cylinder 120 , the compression space P maintains a closed state, and when the discharge valve 161 is spaced apart from the front surface of the cylinder 120 , the compression space P is opened. The compressed refrigerant inside the compression space P may be discharged.

The compression space P is a space formed between the suction valve 135 and the discharge valve 161 . The suction valve 135 is formed on one side of the compression space P, and the discharge valve 161 is disposed on the other side of the compression space P, that is, on the opposite side of the suction valve 135 .

In the process of the piston 130 reciprocating linear motion inside the cylinder 120, when the pressure in the compression space P becomes less than the suction pressure, the suction valve 135 is opened and the refrigerant is sucked into the compression space P. . On the other hand, when the pressure in the compression space (P) is greater than or equal to the suction pressure, the refrigerant in the compression space (P) is compressed in the closed state of the suction valve (135).

When the pressure in the compression space (P) is equal to or greater than the discharge pressure, the valve spring (163a) is deformed forward to open the discharge valve (161), and the refrigerant is discharged from the compression space (P) to discharge the discharge cover (160). discharged into space. When the discharge of the refrigerant is completed, the valve spring 163a provides a restoring force to the discharge valve 161 to close the discharge valve 161 .

The cover pipe 162a is coupled to the discharge cover 160 to discharge the refrigerant flowing through the discharge space 160a of the discharge cover 160 . The cover pipe 162a may be made of a metal material.

The loop pipe 162b is coupled to the cover pipe 162a to transfer the refrigerant flowing through the cover pipe 162a to the discharge pipe 105 . One side of the roof pipe 162b may be coupled to the cover pipe 162a , and the other side may be coupled to the discharge pipe 105 .

The roof pipe 162b is made of a flexible material and may be formed to be relatively long. In addition, the roof pipe 162b may extend from the cover pipe 162a along the inner circumferential surface of the shell 101 in a round shape, and may be coupled to the discharge pipe 105 . For example, the loop pipe 162b may have a wound shape.

The compressor 10 also includes a frame 110 . The frame 110 fixes the cylinder 120 . The cylinder 120 may be press-fitted to the inside of the frame 110 . The cylinder 120 and the frame 110 may be made of aluminum or an aluminum alloy material.

The frame 110 is disposed to surround the cylinder 120 . The cylinder 120 is accommodated inside the frame 110 . The discharge cover 160 may be coupled to the front surface of the frame 110 by a fastening member.

The cylinder 120 includes a cylinder body 121 extending in the axial direction and a cylinder flange 122 provided outside the front portion of the cylinder body 121 . The cylinder body 121 has a cylindrical shape having a central axis in the axial direction and is inserted into the frame 110 . Accordingly, the outer circumferential surface of the cylinder body 121 may be disposed to face the inner circumferential surface of the frame 110 .

The motor assembly 140 includes an outer stator 141 fixed to the frame 110 and arranged to surround the cylinder 120 , an inner stator 148 and an outer stator 141 spaced apart from the inner side of the outer stator 141 . ) and a permanent magnet 146 positioned in the space between the inner stator 148 .

The permanent magnet 146 may reciprocate in a straight line by mutual electromagnetic force with the outer stator 141 and the inner stator 148 . The permanent magnet 146 may be composed of a single magnet having one pole, or a plurality of magnets having three poles are combined.

The permanent magnet 146 may be installed in the magnet frame 138 . The magnet frame 138 has a cylindrical shape and is inserted into a space between the outer stator 141 and the inner stator 148 .

As shown in FIG. 5 , the magnet frame 138 is coupled to the piston flange 132 to extend radially outward and may be bent forward. The permanent magnet 146 may be installed in the front portion of the magnet frame 138 . Therefore, when the permanent magnet 146 reciprocates, the piston 130 reciprocates in the axial direction together with the permanent magnet 146 .

The outer stator 141 includes coil winding bodies 141b, 141c, and 141d and a stator core 141a. The coil winding bodies 141b, 141c, and 141d include a bobbin 141b and a coil 141c wound in a circumferential direction of the bobbin 141b. The coil winding bodies 141b, 141c, and 141d further include a terminal portion 141d for guiding the power line connected to the coil 141c to be drawn out or exposed to the outside of the outer stator 141 .

The stator core 141a includes a plurality of core blocks in which a plurality of laminations are stacked in a circumferential direction. The plurality of core blocks may be disposed to surround at least a portion of the coil winding body (141b, 141c, 141d).

A stator cover 149 is provided on one side of the outer stator 141 . One side of the outer stator 141 is supported by the frame 110 , and the other side is supported by the stator cover 149 .

The stator cover 149 and the frame 110 are fastened by the cover fastening member 149a. The cover fastening member 149a extends forward toward the frame 110 through the stator cover 149 and may be coupled to a fastening hole provided in the frame 110 .

The inner stator 148 is fixed to the outer periphery of the frame 110 . A plurality of laminations are stacked in the circumferential direction from the outside of the frame 110 to constitute the inner stator 148 .

As a predetermined current is applied to the coil 141c, the outer stator 141 and the inner stator 148 form an electric field. By this electric field, the permanent magnet 146 may receive electromagnetic force to reciprocate in the axial direction together with the piston 130 .

The reciprocating speed and distance of the permanent magnet 146 may be changed according to a current value applied to the coil 141c. That is, the movement of the piston 130 may be changed according to a current value applied to the motor assembly 140 .

The compressor 10 further includes a supporter 137 for supporting the piston 130 . The supporter 137 is coupled to the rear side of the piston 130 , and the suction muffler 150 is disposed inside the piston 130 to pass therethrough. The piston flange 132 , the magnet frame 138 , and the supporter 137 may be fastened by a fastening member.

A balance weight 179 is coupled to the supporter 137 . The weight of the balance weight 179 may be determined based on the operating frequency range of the compressor body.

The compressor 10 further includes a rear cover 170 coupled to the stator cover 149 and extending rearwardly supported by the second support device 185 .

The rear cover 170 includes three support legs. The three support legs are coupled to the rear surface of the stator cover 149 . A spacer 181 is interposed between the three support legs and the rear surface of the stator cover 149 . The distance from the stator cover 149 to the rear end of the rear cover 170 is determined according to the thickness of the spacer 181 . The rear cover 170 is elastically supported by the supporter 137 .

In addition, the compressor 10 further includes an inflow guide part 156 coupled to the rear cover 170 to guide the refrigerant inflow into the suction muffler 150 . At least a portion of the inlet guide part 156 may be inserted into the suction muffler 150 .

In addition, the compressor 10 further includes a plurality of resonance springs 176a and 176b each of which natural frequencies are adjusted for the resonance motion of the piston 130 .

The plurality of resonance springs 176a and 176b include a first resonance spring 176a supported between the supporter 137 and the stator cover 149 and a second resonance spring 176a supported between the supporter 137 and the rear cover 170 . It includes a resonance spring (176b). By the action of the plurality of resonance springs 176a and 176b, stable movement of the driving unit reciprocating inside the compressor 10 is ensured, and vibration or noise generation according to the movement of the driving unit is reduced.

The supporter 137 includes a first spring support portion 137a coupled to the first resonance spring 176a.

In addition, the compressor 10 includes a plurality of sealing members (127, 128, 129a, 129b) for increasing the coupling force between the frame 110 and the parts around the frame (110).

The plurality of sealing members 127 , 128 , 129a and 129b include a first sealing member 127 provided at a portion where the frame 110 and the discharge cover 160 are coupled. The first sealing member 127 may be disposed in the first installation groove of the frame 110 .

In addition, the plurality of sealing members (127, 128, 129a, 129b) includes a second sealing member (128) provided at a portion where the frame 110 and the cylinder 120 are coupled. The second sealing member 128 may be disposed in the second installation groove of the frame 110 .

In addition, the plurality of sealing members (127, 128, 129a, 129b) includes a third sealing member (129a) provided between the cylinder (120) and the frame (110). The third sealing member 129a may be disposed in a cylinder groove formed in the rear portion of the cylinder 120 . The third sealing member 129a prevents the refrigerant in the gas pocket formed between the inner circumferential surface of the frame and the outer circumferential surface of the cylinder from leaking to the outside, and increases the coupling force between the frame 110 and the cylinder 120 .

In addition, the plurality of sealing members 127 , 128 , 129a and 129b include a fourth sealing member 129b provided at a portion where the frame 110 and the inner stator 148 are coupled. The fourth sealing member 129b may be disposed in the third installation groove of the frame 110 . The first to fourth sealing members 127, 128, 129a, and 129b may have a ring shape.

In addition, the compressor 10 further includes a first supporting device 165 supporting one side of the main body of the compressor 10 and a second supporting device 185 supporting the other side of the main body of the compressor 10 .

The first support device 165 is disposed adjacent to the second shell cover 103 and is coupled to the discharge cover 160 to elastically support the main body of the compressor 10 . The second support device is coupled to the first shell cover 102 and the rear cover 170 to elastically support the main body of the compressor 10 .

The first support device 165 includes a first support spring 166 coupled to the spring fastening portion 101a shown in FIG. 3 . In addition, the second support device 185 includes a second support spring 186 coupled to the cover support portion 102a shown in FIG. 3 .

In addition, the compressor 10 according to an embodiment of the present specification includes a bearing flow path for supplying a bearing refrigerant to the piston 130 . The bearing coolant is supplied between the piston 130 and the inner wall of the cylinder 120 to perform a bearing function.

The bearing refrigerant is a part of the refrigerant compressed by the piston 130 . The refrigerant compressed in the compression space P by the piston 130 is discharged to the outside. At this time, some refrigerant (bearing refrigerant) of the discharged refrigerant may be supplied between the piston 130 and the cylinder 120 through the frame 110 and the cylinder 120 .

The bearing passage includes cylinder bearing passages 125 and 126 formed in the cylinder 120 and a frame bearing passage 114 formed in the frame 110 . At least a portion of the refrigerant compressed by the piston 130 may flow to the cylinder bearing passages 125 and 126 and the frame bearing passage 114 to be supplied between the piston 130 and the cylinder 120 .

The frame bearing passage 114 is formed through the frame 110 . The frame bearing passage 114 is formed to extend from the front surface of the frame 110 to the outer peripheral surface of the cylinder 120 . Referring to FIG. 5 , the frame bearing flow path 114 is disposed obliquely along the axial direction.

The cylinder bearing passage includes a gas inlet 126 and a cylinder nozzle 125 .

The gas inlet 126 is formed by being recessed in the radial direction from the outer circumferential surface of the cylinder body 121 . The gas inlet 126 may be formed in a circular shape along the outer circumferential surface of the cylinder body 121 with respect to the central axis in the axial direction. In one embodiment of the present specification, a plurality of gas inlet 126 may be provided. For example, the two gas inlets 126 may be disposed to be spaced apart from each other in the axial direction.

The cylinder nozzle 125 is formed to extend from the gas inlet 126 to the inner circumferential surface of the cylinder body 121 . In particular, the cylinder nozzle 125 may extend radially inward from the gas inlet 126 .

The bearing refrigerant corresponds to a portion of the refrigerant flowing through the compressor 10 . Therefore, when the amount of the bearing refrigerant is too large, the amount of the refrigerant compressed by the compressor 10 is reduced. Accordingly, by adjusting the diameter of the cylinder nozzle 125, the amount of the bearing refrigerant can be appropriately adjusted.

A gas pocket may be formed between the cylinder 120 and the frame 110 . A predetermined bearing refrigerant may flow between the outer circumferential surface of the cylinder body 121 and the inner circumferential surface of the frame 110 . Accordingly, the refrigerant flowing along the frame bearing passage 114 may flow to the gas inlet 126 .

The refrigerant that has passed through the gas inlet 126 , that is, the bearing refrigerant is introduced into the space between the inner circumferential surface of the cylinder body 121 and the outer circumferential surface of the piston body 131 through the cylinder nozzle 125 . The bearing refrigerant provides levitation force to the piston 130 to minimize friction with the inner circumferential surface of the cylinder body 121 when the piston 130 reciprocates. More specifically, the bearing refrigerant is supplied to the outer circumferential surface of the piston 130 to separate the piston 130 from the cylinder 120 . Accordingly, friction between the cylinder 120 and the piston 130 is minimized during the reciprocating motion of the piston 130 .

Meanwhile, as described above, when the ambient temperature of the compressor 10 is lowered, the cooling power of the compressor 10 is reduced and the amount of the bearing refrigerant flowing into the cylinder 120 is reduced. When the amount of the bearing refrigerant flowing into the cylinder 120 is reduced, the levitation force of the piston 130 is weakened and the friction between the piston 130 and the cylinder 120 is increased in the reciprocating motion process. Accordingly, wear may occur on the outer surface of the piston 130 or the inner surface of the cylinder 120 . Wear of the piston 130 or the cylinder 120 causes the performance of the compressor 10 to deteriorate. In addition, when the wear of the piston 130 or the cylinder 120 intensifies, a phenomenon in which a part of the surface of the piston 130 or the cylinder 120 is torn off may occur. As a result, this phenomenon may lead to a malfunction of the compressor 10 .

Hereinafter, a control method of the compressor 10 for reducing friction generated between the piston 130 and the cylinder 120 when the ambient temperature of the compressor 10 is lowered will be described.

6 is a block diagram illustrating a configuration of a refrigerator according to an embodiment of the present specification.

Referring to FIG. 6 , the refrigerator 1 according to an embodiment of the present specification includes a main controller 20 , a temperature sensor 214 , a control panel 206 , a compressor controller 204 , and a compressor 10 . .

The temperature sensor 214 measures the ambient temperature of the compressor 10 . As an example of the temperature sensor 214, an outdoor temperature sensor disposed on one side of the refrigerator 1 to measure the temperature outside the refrigerator 1 or disposed inside the machine room 5 to measure the temperature inside the machine room 5 a machine room temperature sensor, but is not limited thereto. For example, when an outdoor temperature sensor is used as the temperature sensor 214 , the temperature outside the refrigerator 1 , that is, the outside temperature may be regarded as the same as the temperature inside the machine room 5 in which the compressor 10 is disposed. The temperature sensor 214 transmits a measured temperature value, that is, an ambient temperature value, to the main controller 20 .

The control panel 206 has an input function for inputting a command or information for use of the refrigerator and a display function for displaying information related to the refrigerator. For example, the user may input a set temperature of the storage compartment, that is, the refrigerating compartment or the freezing compartment, respectively, or change the driving mode of the storage compartment through the control panel 206 . In addition, the control panel 206 displays the set temperature of the storage chamber input by the user or the current temperature inside the storage chamber. The set temperature value of the refrigerating compartment 130 or the set temperature value of the freezing compartment 140 input by the user through the control panel 206 is transmitted to the main controller 20 .

An example of the control panel 206 is a touch panel having an input function and a display function by touch. Another example of the control panel 206 may include a physical input button and a display panel on which information is displayed.

The control panel 206 may be disposed at the end of the cabinet 2 or on the outer surface of the door 3 , but the position of the control panel 206 may vary depending on the embodiment.

The main controller 20 controls the operation of the compressor 10 based on the set temperature value of the storage chamber input through the control panel 206 and the internal temperature of the storage chamber measured by the storage chamber temperature sensor (not shown). output a signal.

In one embodiment of the present specification, the control signal output by the main controller 20 is supplied to the compressor controller 204 . For example, the main controller 20 may supply either a compressor drive signal or a compressor stop signal to the compressor controller 204 .

The compressor controller 204 is electrically connected to the compressor 10 . The compressor controller 204 drives the compressor 10 according to a control signal supplied by the main controller 20 . Upon receiving the compressor driving signal from the main controller 20 , the compressor controller 204 supplies power for driving the compressor 10 . Accordingly, the compressor 10 is driven. Conversely, upon receiving a compressor stop signal from the main controller 20 , the compressor controller 204 stops supplying power to the compressor 10 . Accordingly, the operation of the compressor 10 is stopped.

In one embodiment of the present specification, the compressor controller 204 may control the stroke value of the compressor 10 . The stroke value of the compressor 10 means the distance between the top dead center and the bottom dead center of the piston 130 . Therefore, when the stroke value of the compressor 10 increases, the movement distance of the piston 130 is increased, and the torque of the piston 10 increases. When the stroke value of the compressor 10 decreases, the movement distance of the piston 130 is shortened. The torque of the piston 10 decreases.

In one embodiment of the present specification, the compressor controller 204 controls the stroke value of the compressor not to be lower than the lowest stroke value when the compressor 10 is driven. The lowest stroke value means the smallest value among the stroke values of the compressor 10 , and is set as a predetermined basic stroke value when the compressor 10 is initially driven. Therefore, when the minimum stroke value of the compressor 10 increases, the stroke value of the compressor 10 increases and the torque of the piston increases, and when the minimum stroke value decreases, the stroke value of the compressor 10 decreases and the torque of the piston decreases. do.

Compressor 10 is driven by power supply by compressor controller 204 . When the compressor 10 is driven, the refrigerant compressed by the compressor 10 is supplied to the evaporator disposed at the rear surface of the storage chamber, and cold air is supplied into the storage chamber. Accordingly, the temperature inside the storage chamber decreases. Conversely, when the operation of the compressor 10 is stopped, the supply of cold air into the storage chamber is stopped and the temperature inside the storage chamber rises.

In one embodiment herein, the compressor controller 204 inputs an ambient temperature value measured by a temperature sensor 214 . The compressor control unit 204 may receive an ambient temperature value directly from the temperature sensor 214 , or may receive an ambient temperature value through the main controller 20 .

Compressor controller 204 compares the ambient temperature value to a predetermined reference temperature range. The compressor controller 204 may adjust the stroke value of the compressor 10 according to the comparison result between the ambient temperature value and the reference temperature range.

Hereinafter, embodiments in which the compressor controller 204 adjusts the stroke value of the compressor 10 according to the ambient temperature value are described.

7 is a flowchart illustrating a control method of a linear compressor according to an embodiment of the present specification.

When the refrigerator 1 is turned on and the compressor 10 driving control is started, the compressor controller 204 receives an ambient temperature value measured by the temperature sensor 214 ( 702 ).

The compressor controller 204 compares the input ambient temperature value to a predetermined reference temperature range (704). In one embodiment of the present specification, one or more reference temperature ranges may be set. The compressor controller 204 determines to which temperature range the input ambient temperature value belongs to a predetermined reference temperature range.

The compressor controller 204 adjusts the stroke value of the compressor 10 according to the comparison result of the ambient temperature value and the reference temperature range ( 706 ).

In one embodiment of the present specification, the step 706 of adjusting the stroke value of the compressor 10 includes adjusting the lowest stroke value of the compressor 10 to a value corresponding to the reference temperature range to which the ambient temperature value belongs. do.

Also, in one embodiment of the present specification, the lowest stroke value is set to increase as the ambient temperature value decreases.

In addition, in one embodiment of the present specification, in the step 706 of adjusting the stroke value of the compressor 10, if the ambient temperature value is greater than or equal to a predetermined reference temperature value, the lowest stroke value of the compressor 10 is set to a predetermined basic stroke value. setting, and if the ambient temperature value is less than the reference temperature value, setting the lowest stroke value to a value higher than the basic stroke value.

Also, in one embodiment of the present specification, the step 706 of adjusting the stroke value of the compressor 10 includes setting the stroke value of the compressor 10 to increase as the ambient temperature value decreases.

8 is a flowchart illustrating a control method of a linear compressor according to another embodiment of the present specification.

When power is supplied from an external power source to turn on the power of the refrigerator 1 ( 802 ), the compressor controller 204 controls the operation of the compressor 10 according to a control signal from the main controller 20 ( 804 ). .

While controlling the operation of the compressor 10 , the compressor controller 204 receives an ambient temperature value of the compressor 10 measured by the temperature sensor 214 ( 806 ).

Compressor controller 204 compares the input ambient temperature value to a predetermined reference temperature value (808). For example, the compressor controller 204 determines whether the ambient temperature value is greater than or equal to -8°C, which is a reference temperature value. Here, the reference temperature value is a value that may be set differently depending on the embodiment.

If the ambient temperature value is equal to or higher than the reference temperature value of −8° C., the compressor controller 204 sets the lowest stroke value of the compressor 10 to a predetermined basic stroke value (eg, 8 mm) ( 810 ). Compressor controller 204 accordingly sets the base stroke value to the lowest stroke value and returns to step 804 .

If the ambient temperature value is less than the reference temperature value of −8° C., the compressor controller 204 sets the lowest stroke value of the compressor 10 to a value (eg, 10 mm) greater than the basic stroke value (eg, 8 mm) ( 812 ). ). In other words, the compressor controller 204 sets the lowest stroke value of the compressor 10 to increase when the ambient temperature value decreases.

Compressor controller 204 returns to step 804 based on the newly set lowest stroke value (eg, 10 mm). Accordingly, since the stroke value of the compressor 10 increases, the torque of the compressor 10 increases. When the torque of the compressor 10 increases, the pressure of the refrigerant discharged to the outside after being compressed by the piston 130, that is, the discharge pressure of the refrigerant increases. When the discharge pressure of the refrigerant increases, the refrigerant supplied between the piston 130 and the cylinder 120, that is, the amount of the bearing refrigerant increases, so that the levitation force of the piston 130 does not decrease. Accordingly, since friction between the piston 130 and the cylinder 120 is reduced, the wear rate of the piston 130 or the cylinder 120 is reduced.

In the embodiment of Fig. 8, the compressor controller 204 compares the ambient temperature value with two reference ranges (greater than -8 ° C, less than -8 ° C), and according to the comparison result, the lowest stroke value is set to two stroke values (8 mm, 10mm). However, the reference range and the number of stroke values may vary according to embodiments.

9 is a flowchart illustrating a control method of a linear compressor according to another embodiment of the present specification.

When power is supplied from an external power source to turn on the power of the refrigerator 1 ( 902 ), the compressor controller 204 controls the operation of the compressor 10 according to a control signal from the main controller 20 ( 904 ). .

While controlling the operation of the compressor 10 , the compressor controller 204 receives an ambient temperature value of the compressor 10 measured by the temperature sensor 214 ( 906 ).

The compressor controller 204 determines whether the input ambient temperature value is within a predetermined first reference range ( 908 ). For example, the compressor controller 204 determines whether the ambient temperature value falls within a first reference range (below -8°C and above -10°C).

If the ambient temperature value is included in the first reference range in step 908, the compressor controller 204 sets the lowest stroke value of the compressor 10 to a predetermined first stroke value (eg, 10 mm) (910), and in step 908 . Return to (904).

If the ambient temperature value is not included in the first reference range in step 908 , the compressor controller 204 determines whether the ambient temperature value is included in a predetermined second reference range ( 912 ). For example, the compressor controller 204 determines whether the ambient temperature value falls within the second reference range (below -10°C and above -12°C).

If the ambient temperature value falls within the second reference range in step 912 , the compressor controller 204 sets the lowest stroke value of the compressor 10 to a second predetermined stroke value (eg, 12 mm) ( 914 ); Return to (904).

If the ambient temperature value is not included in the second reference range in step 912 , the compressor controller 204 determines whether the ambient temperature value is included in the third predetermined reference range ( 916 ). For example, the compressor controller 204 determines whether the ambient temperature value falls within a third reference range (less than -12°C).

If the ambient temperature value falls within the third reference range in step 916 , the compressor controller 204 sets the lowest stroke value of the compressor 10 to a third predetermined stroke value (eg, 14 mm) ( 918 ); Return to (904).

If the ambient temperature value is not included in the third reference range in step 916, the compressor controller 204 determines that the ambient temperature value is included in the fourth reference range (-8°C or higher), and sets the lowest stroke value as the basic stroke value (eg, 8 mm) 920 , and return to step 904 .

9, the compressor controller 204 sets the lowest stroke value of the compressor 10 to increase as the ambient temperature value decreases. Accordingly, even if the ambient temperature value decreases, the stroke value of the compressor 10 increases, and thus the torque of the compressor 10 increases. When the torque of the compressor 10 increases, the pressure of the refrigerant discharged to the outside after being compressed by the piston 130, that is, the discharge pressure of the refrigerant increases. When the discharge pressure of the refrigerant increases, the refrigerant supplied between the piston 130 and the cylinder 120, that is, the amount of the bearing refrigerant increases, so that the levitation force of the piston 130 does not decrease. Accordingly, since friction between the piston 130 and the cylinder 120 is reduced, the wear rate of the piston 130 or the cylinder 120 is reduced.

In the embodiment of Fig. 9, the compressor controller 204 sets the ambient temperature value to four reference ranges (above -8°C, below -8°C and above -10°C, below -10°C and above -12°C, below -12°C. ) and set the lowest stroke value to any one of the four stroke values (8mm, 10mm, 12mm, 14mm) according to the comparison result. However, the reference range and the number of stroke values may vary according to embodiments.

10 is a graph showing changes in the pressure of the refrigerant sucked into the linear compressor and the pressure of the refrigerant discharged from the linear compressor according to the driving time of the linear compressor.

In FIG. 10 , when the ambient temperature of the compressor 10 is −10° C., the pressure 1002 (hereinafter, suction pressure) of the refrigerant sucked into the compressor 10 and the piston 130 are compressed inside the compressor 10. Pressures 1004 and 1006 (hereinafter, referred to as discharge pressures) of the refrigerant discharged to the outside are shown respectively.

In addition, in FIG. 10 , the discharge pressure 1004 is the pressure when the lowest stroke value of the compressor 10 is set to 8 mm, and the discharge pressure 1006 is the pressure when the lowest stroke value of the compressor 10 is set to 10 mm. to be.

As shown in FIG. 10 , the suction pressure 1002 of the refrigerant is constant even if the lowest stroke value of the compressor 10 is changed. However, as the minimum stroke value of the compressor 10 increases, the discharge pressure of the refrigerant increases.

Therefore, when the lowest stroke value of the compressor 10 is 8 mm, the difference value between the discharge pressure 1004 and the suction pressure 1002 is 0.8, and when the lowest stroke value of the compressor 10 is 10 mm, the discharge pressure 1006 and The difference value of the suction pressure 1002 becomes 1.1. In other words, as the minimum stroke value of the compressor 10 increases, the difference between the discharge pressure and the suction pressure also increases.

As a result, according to FIG. 10 , as the minimum stroke value of the compressor 10 increases, the pressure (discharge pressure) of the refrigerant discharged from the compressor 10 and the difference between the discharge pressure and the suction pressure increase. According to the control method of the linear compressor according to the present specification, the lower the ambient temperature of the compressor 10, the lower the levitation force of the piston 130 by increasing the minimum stroke value of the compressor 10 based on such characteristics. This is prevented.

11 is a graph showing a change in frictional force between a piston and a cylinder according to a difference value between the pressure of the refrigerant sucked into the linear compressor and the pressure of the refrigerant discharged from the linear compressor.

In FIG. 11 , the horizontal axis represents the pressure difference between the discharge pressure and the suction pressure of the refrigerant, and the vertical axis represents a friction input value that is proportional to the friction force between the piston 130 and the cylinder 120 .

In FIG. 11 , when the friction input value reaches W1 , the piston 130 completely floats in the cylinder 120 , so that friction between the piston 130 and the cylinder 120 does not occur. (Complete floating region) Also, when the friction input value is between W1 and W2, boundary friction occurs between the piston 130 and the cylinder 120 while the piston 130 floats in the cylinder 120. (Boundary friction region) In a state in which the piston 130 does not float in the cylinder 120 , that is, in a state in which the compressor 10 is not driven at all, the friction input value has a value greater than W2 . (Non-operated region) In other words, as the friction input value increases, it means that a sufficient amount of bearing refrigerant is not supplied between the piston 130 and the cylinder 120 .

11 shows the amount of change 1104 in the friction input value according to the pressure difference between the discharge pressure and the suction pressure when the lowest stroke value of the compressor 10 is 8 mm, and the discharge pressure and suction when the lowest stroke value of the compressor 10 is 10 mm. A change amount 1106 of the friction input value according to the pressure difference of the pressure is shown, respectively.

Also, in FIG. 11 , a point 1112 is a value measured when the ambient temperature of the compressor 10 is -5°C, and a point 1114 and a point 1116 are a value measured when the ambient temperature of the compressor 10 is -25°C. It is the measured value.

Referring to FIG. 11 , when the ambient temperature of the compressor 10 is -5°C, the pressure difference between the discharge pressure and the suction pressure of the refrigerant becomes P2 and the friction input value becomes W1 regardless of the lowest stroke value of the compressor 10 . . (See point 1112 ) In other words, when the ambient temperature of the compressor 10 is -5° C., regardless of the lowest stroke value of the compressor 10 , the piston 130 completely floats inside the cylinder 120 and the piston 130 ) and almost no friction between the cylinder 120 .

However, when the ambient temperature of the compressor 10 drops to -25°C, when the minimum stroke value of the compressor 10 is set to 8 mm, the pressure difference between the discharge pressure and the suction pressure of the refrigerant is lowered to P2, and the friction input value is set to W2. increases (See point 1114 ) Accordingly, the piston 130 does not fully float inside the cylinder 120 , and boundary friction occurs between the piston 130 and the cylinder 120 .

On the other hand, when the ambient temperature of the compressor 10 drops to -25° C., when the lowest stroke value of the compressor 10 is set to 10 mm, the pressure difference between the discharge pressure and the suction pressure of the refrigerant is lowered to P2, but the friction input value is W1 is maintained as (Refer to point 1116) In this case, even if the pressure difference between the discharge pressure and the suction pressure of the refrigerant decreases, the torque of the piston 130 increases and the discharge pressure of the refrigerant increases. this increases Accordingly, the piston 130 completely floats inside the cylinder 120 , so that friction between the piston 130 and the cylinder 120 hardly occurs.

As such, as the ambient temperature of the compressor 10 is lowered, if the minimum stroke value of the compressor 10 is increased, the piston 130 can stay in the fully floating region, so friction between the piston 130 and the cylinder 120 is possible. This decreases.

12 and 13 are graphs illustrating a change in the magnitude of a load received by a cylinder according to a driving time of the linear compressor.

12 shows the cylinder 120 measured from the outer lower surface of the cylinder 120 according to the driving time of the compressor 10 when the ambient temperature of the compressor 10 is -25° C. and the lowest stroke value of the compressor 10 is 8 mm. It represents the change in the magnitude of the load received.

13 shows the cylinder 120 measured from the outer lower surface of the cylinder 120 according to the driving time of the compressor 10 when the ambient temperature of the compressor 10 is -25° C. and the lowest stroke value of the compressor 10 is 10 mm. ) represents the change in the magnitude of the load received.

As shown in FIG. 12 , when the ambient temperature of the compressor 10 is -25° C. and the lowest stroke value of the compressor 10 is 8 mm, the piston 130 does not completely float inside the cylinder 120, so that the The maximum value reaches 500.

However, as shown in FIG. 13 , when the ambient temperature of the compressor 10 is -25° C. and the lowest stroke value of the compressor 10 is 10 mm, the piston 130 completely floats inside the cylinder 120, so that the load value The maximum value reaches up to 400.

As a result, when the ambient temperature of the compressor 10 is -25 ℃, the higher the minimum stroke value of the compressor 10, the greater the levitation force of the piston 130, so that the piston 130 can float completely inside the cylinder 120. have.

According to an embodiment of the present specification, as the ambient temperature of the compressor 10 decreases according to the above-described characteristics, the lowest stroke value of the compressor 10 increases, thereby increasing the levitation force of the piston 130 . Accordingly, the possibility of occurrence of friction between the piston 130 and the cylinder 120 is reduced. As a result, the likelihood of wear or failure of the piston 130 or the cylinder 120 may be reduced, and the reliability of the refrigerator 1 may be improved.

As described above, the present specification has been described with reference to the illustrated drawings, but the present specification is not limited by the embodiments and drawings disclosed in the present specification, and various modifications may be made by those skilled in the art. In addition, although the effect according to the configuration of the present specification has not been explicitly described and described while describing the embodiment of the present specification, the effect predictable by the configuration should also be recognized.

Claims (10)

receiving an ambient temperature value of the compressor;
comparing the ambient temperature value to a predetermined reference temperature range; and
adjusting the stroke value of the compressor according to a comparison result of the ambient temperature value and the reference temperature range
How to control a linear compressor.
According to claim 1,
The step of adjusting the stroke value of the compressor is
adjusting the lowest stroke value of the compressor to a value corresponding to a reference temperature range to which the ambient temperature value belongs
How to control a linear compressor.
3. The method of claim 2,
The lowest stroke value is set to increase as the ambient temperature value decreases.
How to control a linear compressor.
According to claim 1,
The step of adjusting the stroke value of the compressor is
setting a minimum stroke value of the compressor as a predetermined basic stroke value when the ambient temperature value is equal to or greater than a predetermined reference temperature value; and
If the ambient temperature value is less than the reference temperature value, setting the lowest stroke value to a value higher than the basic stroke value
How to control a linear compressor.
According to claim 1,
The step of adjusting the stroke value of the compressor is
and setting the stroke value of the compressor to increase as the ambient temperature value decreases.
How to control a linear compressor.
a cabinet in which a storage room is formed;
a compressor that compresses a refrigerant for supplying cold air to the storage chamber and is disposed inside a machine room formed inside the cabinet;
a temperature sensor for measuring the ambient temperature of the compressor;
Comprising a compressor controller for controlling the operation of the compressor,
The compressor controller
receiving the ambient temperature value measured by the temperature sensor, comparing the ambient temperature value with a predetermined reference temperature range, and adjusting the stroke value of the compressor according to the comparison result of the ambient temperature value and the reference temperature range
refrigerator.
7. The method of claim 6,
The compressor controller
adjusting the lowest stroke value of the compressor to a value corresponding to the reference temperature range to which the ambient temperature value belongs
refrigerator.
8. The method of claim 7,
The lowest stroke value is set to increase as the ambient temperature value decreases.
refrigerator.
7. The method of claim 6,
The compressor controller
If the ambient temperature value is greater than or equal to a predetermined reference temperature value, the lowest stroke value of the compressor is set as a predetermined basic stroke value,
If the ambient temperature value is less than the reference temperature value, setting the lowest stroke value to a value higher than the basic stroke value
refrigerator.
7. The method of claim 6,
The compressor controller
Set to increase the stroke value of the compressor as the ambient temperature value decreases
refrigerator.

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