Linear compressor

Abstract

A linear compressor is disclosed. The linear compressor of this specification includes: a frame; an outer stator including a stator core disposed on the frame, teeth extending inwardly from the stator core, and toothed shoes extending circumferentially from the inner ends of the teeth; a coil disposed on the teeth; a cylinder disposed on the frame; a piston disposed inside the cylinder; an inner stator coupled to the outer circumferential surface of the piston, reciprocating axially through electromagnetic interaction with the coil; a magnet disposed on the toothed shoes, facing the inner stator; and a dummy pole disposed on the toothed shoes, positioned axially in front of or behind the magnet, facing the inner stator; the outer stator includes a plurality of core plates stacked axially, the distance between the magnet and the inner stator being different from the distance between the dummy pole and the inner stator.

Description

Technical Field

[0001] This specification relates to linear compressors. More specifically, it relates to a linear compressor comprising a transverse flux reciprocating motor having a direction of flux and a direction of linear reciprocating motion of the piston that form a right angle. Background Technology

[0002] Generally, a compressor is a device that receives power from a power-generating device such as a motor or turbine and compresses working fluids such as air or refrigerant. Specifically, compressors are widely used in industrial and household products, especially in vapor compression refrigeration cycles (hereinafter referred to as "refrigeration cycles").

[0003] Based on the way the refrigerant is compressed, these compressors can be classified into reciprocating compressors, rotary compressors, and scroll compressors.

[0004] Reciprocating compressors compress fluids by creating a compression space between the piston and cylinder and by the piston performing linear reciprocating motion. Rotary compressors compress fluids by using eccentrically rotating rollers inside the cylinder. Scroll compressors compress fluids by using a pair of spirally formed scrolls that mesh and rotate.

[0005] Recently, the use of linear compressors, which utilize linear reciprocating motion instead of a crankshaft, has been gradually increasing among reciprocating compressors. Linear compressors have fewer mechanical losses in converting rotary motion into linear reciprocating motion, thus offering advantages such as increased compressor efficiency and a simpler structure.

[0006] A linear compressor mechanism consists of a cylinder located inside a housing that forms a sealed space and creates a compression chamber. A piston covering the compression chamber reciprocates inside the cylinder. The linear compressor operates by repeatedly drawing fluid from the sealed space into the compression chamber as the piston moves to its bottom dead center (BDC) and compressing and expelling the fluid from the compression chamber as the piston moves to its top dead center (TDC).

[0007] The linear compressor contains a compression unit and a drive unit. The compression unit compresses and discharges the refrigerant while performing resonant motion via a resonant spring, driven by the movement generated by the drive unit.

[0008] The linear compressor's piston repeatedly performs a series of processes, including high-speed reciprocating motion inside the cylinder via a resonant spring, drawing refrigerant into the housing through the suction pipe, and then discharging the refrigerant from the compression space through the forward motion of the piston and moving it to the condenser via the discharge pipe.

[0009] On the other hand, based on the lubrication method, linear compressors can be divided into oil-lubricated linear compressors and gas-lubricated linear compressors.

[0010] An oil-lubricated linear compression mechanism is characterized by storing a predetermined amount of oil inside the housing and using this oil to lubricate the cylinder and piston.

[0011] On the other hand, a gas-lubricated linear compressor mechanism does not store oil inside the housing, but instead guides a portion of the refrigerant discharged from the compression space between the cylinder and the piston and uses the gas force of the refrigerant to lubricate the cylinder and the piston.

[0012] In oil-lubricated linear compressors, relatively cool oil is supplied between the cylinder and piston, thereby preventing the cylinder and piston from overheating due to motor heat or compression heat. Thus, in oil-lubricated linear compressors, the refrigerant flowing through the piston's suction path is prevented from being heated and increasing in specific volume while being drawn into the compression chamber of the cylinder, thereby preventing suction losses in advance.

[0013] However, in oil-lubricated linear compressors, if the oil discharged with the refrigerant into the refrigeration cycle unit fails to be smoothly recovered into the compressor, an oil shortage may occur inside the compressor housing. This oil shortage inside the housing may be a cause of reduced compressor reliability.

[0014] In contrast to oil-lubricated linear compressors, gas-lubricated linear compressors can be miniaturized and use refrigerant to lubricate the cylinder and piston. Therefore, they are advantageous because they do not suffer from reduced compressor reliability due to lack of oil.

[0015] On the other hand, in order to produce the same output as a longitudinal linear motor, existing transverse flux reciprocating motors require more coils than longitudinal linear motors. In this case, the outer diameter of the transverse flux reciprocating motor becomes larger, resulting in a problem of increased height for the linear compressor.

[0016] Furthermore, in existing horizontal flux reciprocating motors, when the mover and stator are eccentric due to tolerances, a side force is generated, which can cause the piston and cylinder to collide. Summary of the Invention

[0017] The problem that the invention aims to solve

[0018] The problem to be solved in this specification is to provide a linear compressor that can reduce the height of the linear compressor by reducing the outer diameter of the transverse flux reciprocating motor.

[0019] Furthermore, the problem to be solved in this specification is to provide a linear compressor that can reduce frictional losses between the mover and the stator caused by lateral force eccentricity.

[0020] Furthermore, the problem to be solved in this specification is to provide a linear compressor that can improve the efficiency of magnetic interaction between the magnet and the piston while using a small number of magnets.

[0021] Furthermore, the problem to be solved in this specification is to provide a linear compressor that can improve the stability of the magnetic interaction between the magnet and the piston.

[0022] Furthermore, the problem to be solved in this specification is to provide a linear compressor that can improve the stability of the axial reciprocating motion of the inner stator and piston, which are the movers.

[0023] Furthermore, the problem to be solved in this specification is to provide a linear compressor that can prevent operator error during the product assembly process.

[0024] In addition, the problem to be solved in this specification is to provide a linear compressor that can reduce the costs incurred in the process of assembling products.

[0025] Furthermore, the problem to be solved in this specification is to provide a linear compressor that can increase the axial movement stroke of the inner stator and piston, which are movers, while using a smaller amount of magnets.

[0026] Furthermore, the problem to be solved in this specification is to provide a linear compressor that enables the piston to reciprocate stably along the axial direction without the need for additional components such as bearings for suspending the piston inside the cylinder.

[0027] Furthermore, the problem to be solved in this specification is to provide a linear compressor that can prevent interference from the electromagnetic interaction between the cylinder and the coil and the inner stator.

[0028] Technical solutions to the problem

[0029] The linear compressor of this specification, used to achieve the above-mentioned objectives, includes: a frame; an outer stator including a stator core disposed on the frame, teeth extending inwardly from the stator core, and toothed shoes extending circumferentially from the inner ends of the teeth; a coil disposed on the teeth; a cylinder disposed on the frame; a piston disposed inside the cylinder; an inner stator coupled to the outer circumferential surface of the piston, reciprocating axially through electromagnetic interaction with the coil; a magnet disposed on the toothed shoes, facing the inner stator; and a dummy pole disposed on the toothed shoes, positioned axially in front of or behind the magnet, facing the inner stator.

[0030] This reduces frictional losses between the piston (moving element) and the cylinder (stator) caused by lateral force eccentricity.

[0031] Furthermore, the outer stator may include a plurality of core plates stacked axially. This axial stacking of the outer stator increases the amount of coils disposed in the teeth of the outer stator. That is, using the same amount of coils, the height of the linear compressor can be reduced by decreasing the outer diameter of the transverse flux reciprocating motor.

[0032] In addition, the distance between the magnet and the inner stator may be different from the distance between the dummy pole and the outer stator.

[0033] Therefore, even when the piston and cylinder are misaligned due to tolerances between the mover and stator, collisions can be prevented by reducing the side force.

[0034] In addition, the radial thickness of the virtual pole can be thinner than the radial thickness of the magnet.

[0035] In addition, the distance between the virtual pole and the inner stator can be greater than the distance between the magnet and the inner stator.

[0036] In addition, the difference between the distance between the virtual pole and the inner stator and the distance between the magnet and the inner stator can be more than 0.1 mm and less than 0.2 mm.

[0037] Furthermore, the distance between the virtual pole and the inner stator in the central region of the virtual pole may be different from the distance between the virtual pole and the inner stator in regions outside the central region of the virtual pole.

[0038] In addition, the distance between the virtual pole and the inner stator in the central region of the virtual pole can be greater than the distance between the virtual pole and the inner stator in regions outside the central region of the virtual pole.

[0039] Additionally, the virtual pole may include a groove formed in the central region.

[0040] In addition, the angle between the two ends of the central region of the virtual pole and the center of the inner stator can be less than 30 degrees.

[0041] In addition, the distance between the virtual pole and the inner stator in the central region of the virtual pole can be smaller than the distance between the virtual pole and the inner stator in regions outside the central region of the virtual pole.

[0042] Additionally, the virtual poles may include slots formed in areas outside the central region.

[0043] In addition, the angle between the two ends of the central region of the virtual pole and the center of the inner stator can be less than 30 degrees.

[0044] Invention Effects

[0045] This specification provides a linear compressor that can reduce the height of the linear compressor by reducing the outer diameter of the horizontal flux reciprocating motor.

[0046] In addition, this specification provides a linear compressor capable of reducing frictional losses between the mover and stator caused by lateral force eccentricity.

[0047] Furthermore, this specification provides a linear compressor that can improve the efficiency of magnetic interaction between the magnet and the piston while using a small number of magnets.

[0048] Furthermore, this specification provides a linear compressor capable of improving the stability of the magnetic interaction between the magnet and the piston.

[0049] Furthermore, this specification provides a linear compressor capable of improving the stability of the axial reciprocating motion of the inner stator and piston, which serve as movers.

[0050] In addition, this specification provides a linear compressor that can prevent operator error during the product assembly process.

[0051] In addition, this specification provides a linear compressor that can reduce costs incurred during product assembly.

[0052] Furthermore, this manual describes a linear compressor that can increase the axial movement stroke of the inner stator and piston, which act as movers, while using a smaller amount of magnets.

[0053] Furthermore, this specification provides a linear compressor that enables a piston to reciprocate stably along the axial direction without the need for additional components such as bearings to suspend the piston inside the cylinder.

[0054] Furthermore, this specification provides a linear compressor capable of preventing interference from the cylinder to the electromagnetic interaction between the coil and the inner stator. Attached Figure Description

[0055] Figure 1 This is a perspective view of a linear compressor according to an embodiment of this specification.

[0056] Figure 2 This is a cross-sectional view of a linear compressor according to an embodiment of this specification.

[0057] Figure 3 This is a perspective view of a driving unit according to an embodiment of this specification.

[0058] Figure 4 This is an exploded perspective view of a driving unit according to an embodiment of this specification.

[0059] Figure 5 This is a top view of a drive unit according to an embodiment of this specification.

[0060] Figure 6 This is a bottom view of a drive unit according to an embodiment of this specification.

[0061] Figure 7 This is a diagram showing the configuration of a drive unit with a portion removed from an embodiment of this specification.

[0062] Figures 8 to 11 This is a schematic diagram of the driving unit in various embodiments of this specification.

[0063] Figures 12 to 14 It is a general representation Figure 7 The diagram is a cross-sectional view of section A-A'.

[0064] Figure 15 This is a schematic diagram illustrating a portion of the toothed shoe, magnet, and inner stator according to an embodiment of this specification.

[0065] Figure 16 This is a schematic diagram illustrating a portion of the toothed shoe, dummy pole, and inner stator according to an embodiment of this specification.

[0066] Figure 17 and Figure 18 This is a diagram illustrating a modified example of a virtual pole according to an embodiment of this specification.

[0067] Figure 19 This is a table comparing the lateral force and back electromotive force of one embodiment of this specification.

[0068] Figure 20 This is a perspective view of a drive unit according to another embodiment of this specification.

[0069] Figure 21 This is an exploded perspective view of the drive unit according to another embodiment of this specification.

[0070] Figure 22 This is a top view of a drive unit according to another embodiment of this specification.

[0071] Figure 23 This is a bottom view of the drive unit according to another embodiment of this specification. Detailed Implementation

[0072] The embodiments disclosed in this specification will now be described in detail with reference to the accompanying drawings, and the same or similar components will be given the same reference numerals regardless of the drawing numbers, and repeated descriptions thereof will be omitted.

[0073] In describing the embodiments disclosed in this specification, if a component is referred to as being "connected" or "coupled" to another component, it should be understood that it may be directly connected to or coupled to the other component, but there may also be other components in between.

[0074] In describing the embodiments disclosed in this specification, if it is determined that the specific description of related well-known technologies makes the essence of the embodiments disclosed in this specification unclear, detailed descriptions thereof will be omitted. The accompanying drawings are only for the purpose of helping to understand the embodiments disclosed in this specification. The technical ideas disclosed in this specification are not limited to the drawings and should be understood to include all modifications, equivalents, and substitutions within the scope of the ideas and technologies of this specification.

[0075] In addition, the terminology disclosure can be replaced by terms such as document, specification, and description.

[0076] Figure 1 This is a perspective view of a compressor according to an embodiment of this specification.

[0077] Reference Figure 1 A linear compressor 100 according to one embodiment of this specification may include a housing 111 and housing covers 112, 113 attached to the housing 111. In a broad sense, housing covers 112, 113 can be understood as a component of housing 111.

[0078] Legs 20 may be attached to the underside of the housing 111. Legs 20 may be attached to the base of a product housing the linear compressor 100. For example, the product may include a refrigerator, and the base may include the refrigerator's mechanical compartment base. As another example, the product may include an outdoor unit of an air conditioner, and the base may include the outdoor unit's base.

[0079] The outer casing 111 has a generally cylindrical shape and can be arranged in a horizontally horizontal or axially horizontal configuration. Figure 1 Based on this, the outer casing 111 extends relatively long in the lateral direction and can have a slightly lower radial height. That is, the linear compressor 100 can have a lower height, for example, when the linear compressor 100 is installed on the machine compartment base of the refrigerator, it has the advantage of being able to reduce the height of the machine compartment.

[0080] In addition, the longitudinal central axis of the outer casing 111 is aligned with the central axis of the main body of the compressor 100, which will be described later, and the central axis of the main body of the compressor 100 is aligned with the central axis of the cylinder 140 and piston 150 that constitute the main body of the compressor 100.

[0081] Terminals 30 may be provided on the outer surface of the housing 111. Terminals 30 can transmit external power to the drive unit 130 of the linear compressor 100. Specifically, terminals 30 can be connected to the leads of the coil 132b.

[0082] A bracket 31 may be provided on the outside of the terminal 30. The bracket 31 may include a plurality of brackets surrounding the terminal 30. The bracket 31 may perform the function of protecting the terminal 30 from external impacts, etc.

[0083] The outer casing 111 has open sides. Outer casing covers 112 and 113 can be attached to the open sides of the outer casing 111. Specifically, the outer casing covers 112 and 113 can include: a first outer casing cover 112, attached to one side of the opening of the outer casing 111; and a second outer casing cover 113, attached to the other side of the opening of the outer casing 111. The internal space of the outer casing 111 can be sealed using the outer casing covers 112 and 113.

[0084] by Figure 1 Based on this, the first housing cover 112 can be located on the right side of the linear compressor 100, and the second housing cover 113 can be located on the left side of the linear compressor 100. In other words, the first housing cover 112 and the second housing cover 113 can face each other. Furthermore, it can be understood that the first housing cover 112 is located on the refrigerant suction side, and the second housing cover 113 is located on the refrigerant discharge side.

[0085] The linear compressor 100 may also include a plurality of pipes 114, 115, 40, which are disposed in the housing 111 or housing cover 112, 113 for refrigerant intake, discharge or injection.

[0086] The plurality of pipes 114, 115, 40 may include: a suction pipe 114 for drawing refrigerant into the interior of the linear compressor 100; a discharge pipe 115 for discharging compressed refrigerant from the linear compressor 100; and a replenishment pipe 40 for replenishing refrigerant to the linear compressor 100.

[0087] For example, the suction pipe 114 can be attached to the first housing cover 112. Refrigerant can be drawn axially into the interior of the linear compressor 100 via the suction pipe 114.

[0088] The discharge pipe 115 can be attached to the outer peripheral surface of the housing 111. The refrigerant drawn in through the suction pipe 114 can be compressed while flowing axially. The compressed refrigerant can be discharged through the discharge pipe 115. The discharge pipe 115 can be positioned closer to the second housing cover 113 than the first housing cover 112.

[0089] The replenishment pipe 40 can be attached to the outer peripheral surface of the housing 111. The operator can inject refrigerant into the interior of the linear compressor 100 through the replenishment pipe 40.

[0090] To avoid interference with the discharge pipe 115, the replenishment pipe 40 can be attached to the housing 111 at a different height than the discharge pipe 115. Here, height can be understood as the distance from the leg 20 in the vertical direction. The discharge pipe 115 and the replenishment pipe 40 are attached to the outer circumference of the housing 111 at different heights, which helps to facilitate operation.

[0091] At least a portion of the second outer casing 113 may be disposed adjacent to the inner circumferential surface of the outer casing 111 corresponding to the portion connected to the replenishment pipe 40. In other words, at least a portion of the second outer casing 113 may act as a barrier to the refrigerant injected via the replenishment pipe 40.

[0092] Therefore, from the perspective of the refrigerant flow path, the flow path of the refrigerant flowing in through the replenishment pipe 40 decreases upon entering the internal space of the outer casing 111 due to the second outer casing cover 113, and then increases again upon passing through the second outer casing cover 113. During this process, the refrigerant pressure decreases, thereby enabling refrigerant vaporization. In this process, the oil contained in the refrigerant can be separated. Therefore, the refrigerant with the separated oil flows into the interior of the piston 150, thereby improving the refrigerant's compression performance. The oil can be understood as the working oil present in the cooling system.

[0093] Figure 2This is a cross-sectional view used to illustrate the structure of the linear compressor 100.

[0094] Hereinafter, the compressor 100 described in this specification will be described as a linear compressor 100 that performs the action of drawing in fluid, compressing it, and discharging the compressed fluid while the piston is in linear reciprocating motion.

[0095] The linear compressor 100 can be a component of a refrigeration cycle, and the fluid compressed in the linear compressor 100 can be a refrigerant circulating in the refrigeration cycle. In addition to the compressor, the refrigeration cycle may also include a condenser, an expansion unit, and an evaporator. Furthermore, the linear compressor 100 can be used as a component of a refrigerator's cooling system, but is not limited to this; it can be widely applied throughout industry.

[0096] Reference Figure 2 The compressor 100 may include a housing 110 and a main body housed inside the housing 110. The main body of the compressor 100 may include: a frame 120; a cylinder 140 fixed to the frame 120; a piston 150 that performs linear reciprocating motion inside the cylinder 140; and a drive unit 130 fixed to the frame 120 that imparts driving force to the piston 150. Here, the cylinder 140 and the piston 150 may also be referred to as compression units 140 and 150.

[0097] The compressor 100 may include a bearing unit for reducing friction between the cylinder 140 and the piston 150. The bearing unit may be an oil bearing or a gas bearing. Alternatively, a mechanical bearing may be used as the bearing unit.

[0098] The main body of the compressor 100 can be elastically supported by support springs 116 and 117 disposed at both ends of the inner side of the housing 110. The support springs 116 and 117 may include a first support spring 116 supporting the rear of the main body and a second support spring 117 supporting the front of the main body. The support springs 116 and 117 may include leaf springs. While supporting the internal components of the compressor 100 main body, the support springs 116 and 117 can absorb vibrations and impacts generated by the reciprocating motion of the piston 150.

[0099] The housing 110 can form a sealed space. The sealed space may include: a receiving space 101 for receiving the drawn-in refrigerant; a suction space 102 filled with the refrigerant before compression; a compression space 103 for compressing the refrigerant; and a discharge space 104 filled with the compressed refrigerant.

[0100] The refrigerant drawn in from the suction pipe 114 connected to the rear side of the housing 110 fills the receiving space 101. The refrigerant in the suction space 102, which is connected to the receiving space 101, is compressed in the compression space 103 and discharged into the discharge space 104. It can also be discharged to the outside through the discharge pipe 115 connected to the front side of the housing 110.

[0101] The housing 110 may include: an outer shell 111, open at both ends and formed into a generally laterally elongated cylindrical shape; a first outer shell cover 112, attached to the rear side of the outer shell 111; and a second outer shell cover 113, attached to the front side of the outer shell 111. Here, "front side" can be interpreted as the direction in which compressed refrigerant is discharged from the left side of the drawing, and "rear side" as the direction in which refrigerant flows in from the right side of the drawing. Furthermore, the first outer shell cover 112 or the second outer shell cover 113 may be integrally formed with the outer shell 111.

[0102] The housing 110 can be formed of a thermally conductive material. This allows heat generated inside the housing 110 to be quickly dissipated to the outside.

[0103] The first outer cover 112 is attached to the outer cover 111 to seal the rear side of the outer cover 111, and an inhalation tube 114 can be inserted into the center of the first outer cover 112.

[0104] The rear side of the compressor body 100 can be elastically supported radially by a first support spring 116 on the first housing cover 112.

[0105] The first support spring 116 may include a circular leaf spring. The edge of the first support spring 116 may be elastically supported by the support bracket 123a in the forward direction relative to the rear cover 123. The central portion of the opening of the first support spring 116 may be supported by the suction guide 116a in the rearward direction relative to the first outer cover 112.

[0106] The suction guide 116a may have a through flow path formed internally. The suction guide 116a may be cylindrical. The suction guide 116a has a central opening of the first support spring 116 attached to its front outer peripheral surface, while its rear end may be supported by the first outer casing 112. At this time, an additional suction-side support member 116b may also be provided between the inner surface of the suction guide 116a and the first outer casing 112.

[0107] The rear side of the intake guide 116a is connected to the intake pipe 114, and the refrigerant drawn in through the intake pipe 114 can flow smoothly into the muffler unit 160 described later through the intake guide 116a.

[0108] A damping member 116c may be disposed between the intake guide 116a and the intake-side support member 116b. The damping member 116c may be formed of a rubber material or the like. This prevents vibrations that may occur during the intake of refrigerant through the intake pipe 114 from being transmitted to the first outer casing 112.

[0109] The second outer cover 113 is attached to the outer cover 111 to seal the front side of the outer cover 111, and the discharge pipe 115 can be inserted and attached via the circulation pipe 115a. The refrigerant discharged from the compression space 103 can be discharged into the refrigeration cycle via the circulation pipe 115a and the discharge pipe 115 after passing through the discharge cover assembly 180.

[0110] The front side of the compressor body 100 can be radially elastically supported by the second support spring 117 along the outer casing 111 or the second outer casing cover 113.

[0111] The second support spring 117 may include a circular leaf spring. The central portion of the opening of the second support spring 117 may be supported rearward relative to the ejector cap assembly 180 by the first support guide 117b. The edge portion of the second support spring 117 may be supported forward by the support bracket 117a relative to the inner side of the outer casing 111 or the inner peripheral surface of the outer casing 111 adjacent to the second outer casing cover 113.

[0112] and Figure 2 In contrast, the edge of the second support spring 117 can also be supported in the forward direction relative to the inner side of the housing 111 or the inner peripheral surface of the housing 111 adjacent to the second housing cover 113 by a separate bracket (not shown) attached to the second housing cover 113.

[0113] The first support guide 117b can be formed in a cylindrical shape. The cross-section of the first support guide 117b can include a plurality of diameters. The front side of the first support guide 117b can be inserted into the central opening of the second support spring 117, and the rear side can be inserted into the central opening of the ejector cap assembly 180. The support cap 117c can be attached to the front side of the first support guide 117b through the second support spring 117. A second support guide 117d with a front-recessed cup shape can be attached to the front side of the support cap 117c. A third support guide 117e with a rear-recessed cup shape corresponding to the second support guide 117d can be attached to the inner side of the second outer cover 113. The second support guide 117d is inserted into the inner side of the third support guide 117e and can be supported axially and / or radially. At this time, a gap can be formed between the second support guide 117d and the third support guide 117e.

[0114] The frame 120 may include: a main body 121 that supports the outer peripheral surface of the cylinder 140; and a first flange 122 that is connected to one side of the main body 121 and supports the drive unit 130. The frame 120, the drive unit 130, and the cylinder 140 together can be elastically supported by a first support spring 116 and a second support spring 117 on the housing 110.

[0115] The main body 121 may surround the outer peripheral surface of the cylinder 140. The main body 121 may be formed in a cylindrical shape. The first flange 122 may be formed extending radially from the front end of the main body 121.

[0116] A cylinder 140 may be attached to the inner circumferential surface of the main body 121. For example, the cylinder 140 may be press-fitted and fixed to the inner circumferential surface of the main body 121.

[0117] An outer stator 131 may be attached to the rear side of the first flange portion 122, and a discharge cap assembly 180 may be attached to the front side. For example, the outer stator 131 and the discharge cap assembly 180 may be fixed by a mechanical coupling unit.

[0118] The frame 120 and cylinder 140 can be formed of aluminum or aluminum alloy.

[0119] The cylinder 140 can be formed into a cylindrical shape with open ends. The piston 150 can be inserted through the rear end of the cylinder 140. The front end of the cylinder 140 can be closed by the discharge valve assembly 170. A compression space 103 can be formed between the cylinder 140, the front end of the piston 150, and the discharge valve assembly 170. Here, the front end of the piston 150 can be referred to as the head 151. The volume of the compression space 103 increases when the piston 150 retracts and decreases when the piston 150 advances. That is, the refrigerant flowing into the compression space 103 is compressed when the piston 150 advances and can be discharged through the discharge valve assembly 170.

[0120] The cylinder 140 may include a second flange 141 disposed at its front end. The second flange 141 may be bent outward of the cylinder 140. The second flange 141 may extend along the outer periphery of the cylinder 140. The second flange 141 of the cylinder 140 may be coupled to the frame 120. For example, the front end of the frame 120 may have a flange groove corresponding to the second flange 141 of the cylinder 140, into which the second flange 141 of the cylinder 140 is inserted and coupled by a coupling member.

[0121] Alternatively, a gas bearing unit can be provided, which supplies exhaust gas to the gap between the outer peripheral surface of the piston 150 and the outer peripheral surface of the cylinder 140 to perform gas lubrication between the cylinder 140 and the piston 150. The exhaust gas between the cylinder 140 and the piston 150 provides a levitation force to the piston 150, thereby reducing the friction generated between the piston 150 and the cylinder 140.

[0122] The inner stator 134 and outer stator 131 of the cylinder 140 may not overlap radially. This prevents the cylinder 140 from interfering with the electromagnetic interaction between the coil 132 and the inner stator 134.

[0123] The piston 150 is inserted into the open end behind the cylinder 140, behind the sealed compression space 103.

[0124] The piston 150 may include a head 151 and a guide portion 152. The head 151 may be formed in a circular plate shape. The head 151 may be partially open. The head 151 may divide a compression space 103. The guide portion 152 may extend rearward from the outer periphery of the head 151. The guide portion 152 may be formed in a cylindrical shape. The interior of the guide portion 152 is hollow, and the front can be partially sealed by the head 151. The rear opening of the guide portion 152 may be connected to the muffler unit 160. The head 151 may be a separate component combined with the guide portion 152. Alternatively, the head 151 and the guide portion 152 may be formed integrally.

[0125] The piston 150 can be connected to the inner stator 134. The inner stator 134 can be disposed on the outer peripheral surface of the piston 150. The inner stator 134 can be disposed on the outer peripheral surface of the guide portion 152 of the piston 150. The inner stator 134 can be fixed and engaged with the outer peripheral surface of the guide portion 152 of the piston 150. The outer peripheral surface of the piston 150 can be engaged with the inner peripheral surface of the inner stator 134. For example, the guide portion 152 of the piston 150 can be pressed into the inner peripheral surface engaged with the inner stator 134. The piston 150 can reciprocate in the front-back direction or axial direction as the inner stator 134 moves.

[0126] Piston 150 may include a suction port 154. Suction port 154 may extend through head 151. Suction port 154 may connect suction space 102 and compression space 103 inside piston 150. For example, refrigerant flowing from receiving space 101 into suction space 102 inside piston 150 may be drawn into compression space 103 between piston 150 and cylinder 140 through suction port 154.

[0127] The intake port 154 may extend along the axial direction of the piston 150. The intake port 154 may be formed obliquely to the axial direction of the piston 150. For example, the intake port 154 may extend obliquely away from the central axis as it approaches the rear of the piston 150.

[0128] The cross-section of the suction port 154 can be formed in a circular shape. The suction port 154 can be formed with a constant inner diameter. In contrast, the suction port 154 can be formed as an elongated hole with the opening extending radially along the head 151, or it can be formed as the inner diameter gradually increases as it approaches the rear.

[0129] The suction port 154 may be formed in a plurality of directions in one or more of the radial and circumferential directions of the head 151.

[0130] A suction valve 155, which selectively opens and closes the suction port 154, can be installed on the head 151 of the piston 150 adjacent to the compression chamber 103. The suction valve 155 actuates by elastic deformation, thereby opening or closing the suction port 154. That is, the suction valve 155 can be opened by the pressure elastic deformation of the refrigerant flowing into the compression chamber 103 through the suction port 154.

[0131] The muffler unit 160 is attached to the rear of the piston 150, thereby attenuating the noise generated during the refrigerant intake process of the piston 150. The refrigerant drawn in through the intake pipe 114 can flow through the muffler unit 160 into the intake space 102 inside the piston 150.

[0132] The muffler unit 160 may include: an intake muffler 161 communicating with the receiving space 101 of the housing 110; and an internal guide 162 connected to the front of the intake muffler 161 and guiding refrigerant to the intake port 154.

[0133] The intake muffler 161 is located behind the piston 150, with its rear opening adjacent to the intake pipe 114 and its front end connected to the rear of the piston 150. The intake muffler 161 forms an axial flow path, which can guide the refrigerant in the receiving space 101 to the intake space 102 inside the piston 150.

[0134] The interior of the intake muffler 161 can form a plurality of silencing spaces divided by baffles. The intake muffler 161 can be formed by combining two or more components together; for example, a plurality of silencing spaces can be formed when a second intake muffler is pressed into and combined with the interior of the first intake muffler. Furthermore, considering weight and insulation, the intake muffler 161 can be made of plastic material.

[0135] One side of the internal guide 162 can communicate with the silencing space of the intake muffler 161, and the other side can be deeply inserted into the interior of the piston 150. The internal guide 162 can be formed in a pipe shape. Both ends of the internal guide 162 can have the same inner diameter. The internal guide 162 can be formed in a cylindrical shape. In contrast, the inner diameter of the front end, which is the discharge side, can be larger than the inner diameter of the rear end, which is the opposite side.

[0136] The intake muffler 161 and the internal guide 162 can have various shapes, thereby allowing for the regulation of the refrigerant pressure passing through the muffler unit 160. The intake muffler 161 and the internal guide 162 can also be integrally formed.

[0137] The discharge valve assembly 170 may include: a discharge valve 171; and a valve spring 172 disposed on the front side of the discharge valve 171, elastically supporting the discharge valve 171. The discharge valve assembly 170 can selectively discharge refrigerant compressed in the compression space 103. Here, the compression space 103 refers to the space formed between the suction valve 155 and the discharge valve 171.

[0138] Discharge valve 171 can be configured to be supported on the front of cylinder 140. Discharge valve 171 can selectively open and close the front opening of cylinder 140. Discharge valve 171 can be actuated by elastic deformation, thereby opening or closing compression space 103. Discharge valve 171 can be opened by the pressure elastic deformation of refrigerant flowing into discharge space 104 through compression space 103. For example, when discharge valve 171 is supported on the front of cylinder 140, compression space 103 remains closed, and when discharge valve 171 is separated from the front of cylinder 140, compressed refrigerant in compression space 103 can be discharged through the open space.

[0139] A valve spring 172 is disposed between the discharge valve 171 and the discharge cover assembly 180, thereby providing an axial elastic force. The valve spring 172 may also be a compression coil spring, or, considering space and reliability, a leaf spring.

[0140] If the pressure in the compression space 103 reaches or exceeds the discharge pressure, the valve spring 172 deforms forward while opening the discharge valve 171, allowing refrigerant to be discharged from the compression space 103 and into the first discharge space 104a of the discharge cover assembly 180. Once the refrigerant discharge is complete, the valve spring 172 can provide a restoring force to the discharge valve 171 to close it.

[0141] The following describes the process by which refrigerant flows into the compression space 103 through the suction valve 155, and the refrigerant in the compression space 103 is discharged into the discharge space 104 through the discharge valve 171.

[0142] During the reciprocating linear motion of piston 150 inside cylinder 140, if the pressure in compression space 103 falls below a preset suction pressure, refrigerant is drawn into compression space 103 when suction valve 155 opens. On the other hand, if the pressure in compression space 103 exceeds the preset suction pressure, the refrigerant in compression space 103 is compressed when suction valve 155 is closed.

[0143] On the other hand, if the pressure in the compression space 103 reaches or exceeds the preset discharge pressure, the valve spring 172 deforms forward while opening the discharge valve 171 connected to it, and the refrigerant is discharged from the compression space 103 into the discharge space 104 of the discharge cover assembly 180. Once the refrigerant discharge is complete, the valve spring 172 provides a restoring force to the discharge valve 171, and the discharge valve 171 closes, sealing the front of the compression space 103.

[0144] The discharge cap assembly 180 is disposed in front of the compression space 103, forming a discharge space 104 that accommodates the refrigerant discharged from the compression space 103. It is coupled to the front of the frame 120, thereby reducing noise generated during the discharge of refrigerant from the compression space 103. The discharge cap assembly 180 accommodates the discharge valve assembly 170 and can be coupled to the front of the first flange portion 122 of the frame 120. For example, the discharge cap assembly 180 can be coupled to the first flange portion 122 by a mechanical coupling member.

[0145] Furthermore, a gasket for heat insulation and an O-ring to suppress refrigerant leakage in the discharge space 104 may be provided between the discharge cap assembly 180 and the frame 120.

[0146] The discharge cap assembly 180 can be formed of a thermally conductive material. Therefore, if hot refrigerant flows into the discharge cap assembly 180, the heat of the refrigerant is transferred to the housing 110 through the discharge cap assembly 180, thereby dissipating heat to the outside of the compressor.

[0147] The dispensing cap assembly 180 can be formed from a single dispensing cap, or it can be configured as a plurality of dispensing caps connected in sequence. When the dispensing cap assembly 180 is configured as a plurality of dispensing caps, the dispensing space can include a plurality of spatial portions divided by each dispensing cap. The plurality of spatial portions are arranged in the front-back direction and can communicate with each other.

[0148] For example, when there are three dispensing caps, the dispensing space 104 may include: a first dispensing space 104a, formed between the first dispensing cap 181 attached to the front side of the frame 120 and the frame 120; a second dispensing space 104b, communicating with the first dispensing space 104a, formed between the second dispensing cap 182 attached to the front side of the first dispensing cap 181 and the first dispensing cap 181; and a third dispensing space 104c, communicating with the second dispensing space 104b, formed between the third dispensing cap 183 attached to the front side of the second dispensing cap 182 and the second dispensing cap 182.

[0149] Furthermore, the first discharge space 104a can be selectively connected to the compression space 103 via the discharge valve 171, the second discharge space 104b can be connected to the first discharge space 104a, and the third discharge space 104c can be connected to the second discharge space 104b. Thus, the refrigerant discharged from the compression space 103 passes sequentially through the first discharge space 104a, the second discharge space 104b, and the third discharge space 104c, thereby attenuating the discharge noise and allowing it to be discharged to the outside of the housing 110 via the circulation pipe 115a and the discharge pipe 115 connected to the third discharge cover 183.

[0150] The drive unit 130 may include: an outer stator 131 coupled to the frame 120 between the housing 111 and the frame 120; a coil 132 disposed on the outer stator 132; and an inner stator 134 coupled to the piston 150.

[0151] When current is applied to the drive unit 130, a magnetic flux is formed in the coil 132. Electromagnetic force is generated through the interaction between the magnetic flux formed in the winding coil of the outer stator 131 and the inner stator 134, which is a magnetic body, thereby allowing the inner stator 134 to move. Furthermore, while the inner stator 134 reciprocates axially, the piston 150 connected to the inner stator 134 can also reciprocate axially along with the inner stator 134.

[0152] On the other hand, the drive unit 130 and the compression units 140 and 150 can be axially supported by the support springs 116 and 117 and the resonant spring 118.

[0153] The resonant spring 118 enables efficient refrigerant compression by increasing the vibration generated by the reciprocating motion of the inner stator 134 and the piston 150. Specifically, the resonant spring 118 is tuned to a frequency corresponding to the natural frequency of the piston 150, allowing the piston 150 to resonate. Furthermore, the resonant spring 118 induces stable movement of the piston 150, thereby reducing vibration and noise.

[0154] The resonant spring 118 can be a helical spring extending axially. Both ends of the resonant spring 118 can be connected to a vibrating body and a fixed body, respectively. For example, one end of the resonant spring 118 can be connected to the piston 150, and the other end can be connected to the rear cover 123. Therefore, the resonant spring 118 can elastically deform between the vibrating body that vibrates at one end and the fixed body fixed to the other end.

[0155] The natural frequency of the resonant spring 118 is designed to match the resonant frequency of the inner stator 134 and piston 150 when the compressor 100 is running, thereby increasing the reciprocating motion of the piston 150. However, here, the rear cover 123, which is a fixed body, can be elastically supported on the housing 110 by the first support spring 116, so it may not be a fixed body in the strict sense.

[0156] The resonant spring 118 may include a first resonant spring 118a supported on the rear side with reference to the spring support member 119 and a second resonant spring 118b supported on the front side.

[0157] The spring support 119 may include: a main body 119a surrounding the intake muffler 161; a second connecting part 119b bending radially inward from the front of the main body 119a; and a support part 119c bending radially outward from the rear of the main body 119a.

[0158] The second connecting portion 119b of the spring support 119 can be supported by the piston 150. The inner diameter of the second connecting portion 119b of the spring support 119 can surround the outer diameter of the intake muffler 161. For example, the second connecting portion 119b of the spring support 119 and the third flange portion 153 of the piston 150 are arranged sequentially and then integrally joined by a mechanical component. At this time, the fourth flange portion 161a of the intake muffler 161 can be clamped and fixed together.

[0159] The first resonant spring 118a can be disposed between the front of the rear cover 123 and the rear of the spring support 119. The second resonant spring 118b can be disposed between the rear of the stator cover 137 and the front of the spring support 119.

[0160] Multiple first resonant springs 118a and second resonant springs 118b can be arranged circumferentially along the central axis. The first resonant springs 118a and second resonant springs 118b can be arranged side-by-side along the axial direction or staggered from each other. The first resonant springs 118a and second resonant springs 118b can be arranged at predetermined intervals along the radial direction of the central axis. For example, three of each of the first resonant springs 118a and second resonant springs 118b can be provided, arranged at 120-degree intervals along the radial direction of the central axis.

[0161] The compressor 100 may include a plurality of sealing members, which may increase the bonding force between the frame 120 and its surrounding components.

[0162] For example, the plurality of sealing members may include: a first sealing member, clamped at the junction of the frame 120 and the ejector cap assembly 180, and inserted into a mounting groove provided at the front end of the frame 120; and a second sealing member, provided at the junction of the frame 120 and the cylinder 140, and inserted into a mounting groove provided on the outer surface of the cylinder 140. The second sealing member can increase the bonding force between the frame 120 and the cylinder 140.

[0163] The operation of the linear compressor 100 described above is as follows.

[0164] First, if current is applied to the drive unit 130, the current flowing through the coil 132 can create a magnetic flux in the outer stator 131. The magnetic flux formed in the outer stator 131 generates an electromagnetic force, and the inner stator 134, as a magnetic body, can reciprocate linearly by the generated electromagnetic force. This electromagnetic force can be alternately generated in the following directions: during the compression stroke, the piston 150 is directed towards the top dead center (TDC) (forward direction) and during the intake stroke, the piston 150 is directed towards the bottom dead center (BDC) (rearward direction). That is, the drive unit 130 can generate a pushing force (thrust) that propels the inner stator 134 and the piston 150 along the direction of movement.

[0165] The piston 150, which reciprocates linearly inside the cylinder 140, can repeatedly increase or decrease the volume of the compression space 103.

[0166] If piston 150 moves in the direction of increasing the volume of compression space 103 (rearward direction), the pressure in compression space 103 can decrease. Therefore, the suction valve 155, located in front of piston 150, opens, allowing refrigerant retained in suction space 102 to be drawn into compression space 103 via suction port 154. During this suction stroke, piston 150 can maximize the volume of compression space 103 until it reaches bottom dead center.

[0167] The piston 150, upon reaching bottom dead center, reverses its direction of movement, allowing it to perform a compression stroke while moving in the direction of decreasing volume (forward direction) of the compression chamber 103. During the compression stroke, the pressure in the compression chamber 103 increases, thereby compressing the drawn-in refrigerant. If the pressure in the compression chamber 103 reaches a set pressure, the discharge valve 171 is pushed open by the pressure in the compression chamber 103, thereby opening the cylinder 140 and allowing the refrigerant to be discharged through the partitioned space into the discharge chamber 104. This compression stroke can continue while the piston 150 moves to top dead center, where the volume of the compression chamber 103 becomes minimal.

[0168] During the repeated intake and compression strokes of piston 150, refrigerant flowing into the receiving space 101 inside compressor 100 via intake pipe 114 passes sequentially through intake guide 116a, intake muffler 161, and internal guide 162 into intake space 102 inside piston 150. During the intake stroke of piston 150, the refrigerant in intake space 102 can flow into compression space 103 inside cylinder 140. During the compression stroke of piston 150, the refrigerant forming compression space 103 is compressed and discharged into discharge space 104, then discharged to the outside of compressor 100 via circulation pipe 115a and discharge pipe 115.

[0169] Figure 3 This is a perspective view of a driving unit according to an embodiment of this specification. Figure 4 This is an exploded perspective view of a driving unit according to an embodiment of this specification. Figure 5 This is a top view of a drive unit according to an embodiment of this specification. Figure 6 This is a bottom view of a drive unit according to an embodiment of this specification. Figure 7 This is a diagram showing the configuration of a drive unit with a portion removed from an embodiment of this specification. Figures 8 to 11 This is a schematic diagram of the driving unit in various embodiments of this specification. Figures 12 to 14 It is a general representation Figure 7 The diagram is a cross-sectional view of section A-A'.

[0170] Reference Figures 1 to 14 The linear compressor 100 of one embodiment of this specification may include a frame 120, a drive unit 130, a cylinder 140, and a piston 150, but additional configurations are not excluded. It can be understood that the detailed configurations of the linear compressor 100, the frame 120, the drive unit 130, the cylinder 140, and the piston 150 not described below are not related to the specifications provided. Figure 2 The detailed configuration of the linear compressor 100, frame 120, drive unit 130, cylinder 140 and piston 150 described herein are the same.

[0171] The drive unit 130 can be a transverse flux type reciprocating motor in which the direction of the flux and the linear motion direction of the piston 150 form a right angle. In the embodiments of this specification, the drive unit 130 can be referred to as a "transverse flux type reciprocating motor".

[0172] The drive unit 130 may include an outer stator 131, a coil 132, an inner stator 134, a magnet 135, and a dummy pole 136.

[0173] The outer stator 131 can be coupled to the frame 120. The outer stator 131 can be coupled to the frame 120 via a mechanical unit. The outer stator 131 can be connected to the frame 120. The outer stator 131 can be supported by the frame 120. The outer stator 131 can be coupled to the rear of the first flange 122 of the frame 120. The front side of the outer stator 131 can be supported by the first flange 122 of the frame 120, and the rear side can be supported by the stator cover 137. The stator cover 137 is formed as a hollow circular plate, with the outer stator 131 coupled to its front side, and the resonant spring 118 supported at its rear side.

[0174] The stator cover 137 can be attached to the rear of the outer stator 131, and the stator cover 137 can be connected to the piston 150 via an elastic member 136a. Thus, the piston 150 can reciprocate stably along the axial direction without the need for additional bearings or other components to suspend the piston 150 inside the cylinder 140. In this case, the elastic member 136a can be formed as a leaf spring, but is not limited to this and can be varied in many ways.

[0175] A coil 132 may be mounted on the outer stator 131. The coil 132 may be wound around the outer stator 131. The outer stator 131 may be a magnetic material. When an current is applied, a magnetic flux may be formed in the outer stator 131 through the coil 132.

[0176] The outer stator 131 may include a stator core 131a, a tooth portion 131b, and a tooth shoe 131c.

[0177] The stator core 131a can be attached to the frame 120. The cross-section of the stator core 131a can be circular. The stator core 131a can be formed into a cylindrical shape with an open upper and lower part. The stator core 131a can be formed into a ring shape. Teeth 131b can be formed on the inner circumferential surface of the stator core 131a.

[0178] The outer stator 131 may include a plurality of core plates 131a1, 131a2, ..., 131an. The plurality of core plates 131a1, 131a2, ..., 131an may be stacked along the axial or longitudinal direction of the linear compressor 100. By stacking the plurality of core plates 131a1, 131a2, ..., 131an along the axial or longitudinal direction of the linear compressor 100, the axial length of the stator core 131a and the tooth portion 131b increases, thereby increasing the amount of coil 132 wound around the tooth portion 131b, which allows for a reduction in the outer diameter of the drive unit 130. Furthermore, the vertical height of the linear compressor 100 can be reduced by decreasing the outer diameter of the drive unit 130. That is, using the same amount of coil 132, the height of the linear compressor 100 can be reduced by decreasing the outer diameter of the transverse flux reciprocating motor.

[0179] The tooth 131b can extend inward toward the stator core 131a. A coil 132 can be disposed in the tooth 131b. The coil 132 can be wound around the tooth 131b. When current is applied to the coil 132, magnetic flux can be formed through the coil 132 in the tooth 131b, the stator core 131a, and the tooth shoe 131c. A tooth shoe 131c extending circumferentially can be formed at the inner end of the tooth 131b. The cross-section of the tooth 131b can be quadrilateral, but is not limited thereto, and can also be formed as a polygon other than a circle or a quadrilateral.

[0180] The tooth portion 131b may include a plurality of teeth 131b1, 131b2, 131b3, and 131b4. The plurality of teeth 131b1, 131b2, 131b3, and 131b4 may be formed in an even number. The plurality of teeth 131b1, 131b2, 131b3, and 131b4 may be circumferentially spaced from each other. The plurality of teeth 131b1, 131b2, 131b3, and 131b4 may be arranged symmetrically with respect to the center of the outer stator 131. The plurality of teeth 131b1, 131b2, 131b3, and 131b4 may be arranged radially with respect to the center of the outer stator 131. The plurality of teeth 131b1, 131b2, 131b3, and 131b4 may be arranged symmetrically with respect to the center of the piston 150. The circumferential spacing and / or angle of each of the plurality of teeth 131b1, 131b2, 131b3, 131b4 may be the same as each other.

[0181] The plurality of teeth 131b1, 131b2, 131b3, and 131b4 may include a first tooth 131b1, a second tooth 131b2 spaced circumferentially from the first tooth 131b1, a third tooth 131b3 spaced circumferentially from the second tooth 131b2, and a fourth tooth 131b4 spaced circumferentially from the third tooth 131b3. The first coil 132a to the fourth coil 132d may be wound around the fourth tooth 131b4 within the first tooth 131b1. The embodiments described in this specification use an example of four teeth 131b1, 131b2, 131b3, and 131b4, but are not limited to this; the number of teeth 131b1, 131b2, 131b3, and 131b4 can vary considerably.

[0182] The toothed shoe 131c can extend circumferentially inside the tooth portion 131b. Specifically, the toothed shoe 131c can extend circumferentially at the inner end of the tooth portion 131b. The toothed shoe 131c can be formed in an arc shape. The toothed shoe 131c can face the inner stator 134. A magnet 135 can be disposed on the toothed shoe 131c. A magnet 135 can be disposed on the inner side of the toothed shoe 131c. A dummy pole 136 can be disposed on the toothed shoe 131c. A dummy pole 136 can be disposed on the inner side of the toothed shoe 131c.

[0183] The toothed shoe 131c may include a plurality of toothed shoes 131c1, 131c2, 131c3, and 131c4. The plurality of toothed shoes 131c1, 131c2, 131c3, and 131c4 may be an even number. The plurality of toothed shoes 131c1, 131c2, 131c3, and 131c4 may be circumferentially spaced from each other. The plurality of toothed shoes 131c1, 131c2, 131c3, and 131c4 may be arranged symmetrically with respect to the center of the outer stator 131. The plurality of toothed shoes 131c1, 131c2, 131c3, and 131c4 may be arranged radially with respect to the center of the outer stator 131. The plurality of toothed shoes 131c1, 131c2, 131c3, and 131c4 may be arranged symmetrically with respect to the center of the piston 150. The circumferential spacing and / or angle between each of the plurality of toothed boots 131c1, 131c2, 131c3, and 131c4 may be the same for each other.

[0184] The plurality of toothed boots 131c1, 131c2, 131c3, and 131c4 may include a first toothed boot 131c1, a second toothed boot 131c2 spaced circumferentially from the first toothed boot 131c1, a third toothed boot 131c3 spaced circumferentially from the second toothed boot 131c2, and a fourth toothed boot 131c4 spaced circumferentially from the third toothed boot 131c3. Each of the first toothed boots 131c1 to the fourth toothed boot 131c4 may be connected to a first tooth portion 131b1 to a fourth tooth portion 131b4 respectively. The embodiments described in this specification are illustrated using an example of four teeth 131c1, 131c2, 131c3, and 131c4, but the embodiment is not limited thereto, and the number of teeth 131c1, 131c2, 131c3, and 131c4 may vary considerably.

[0185] Coil 132 can be disposed on outer stator 131. Coil 132 can be disposed on tooth 131b of outer stator 131. Coil 132 can be wound on tooth 131b of outer stator 131. Current can be supplied to coil 132. The cross-section of coil 132 can be formed into a circular or polygonal shape. As an example, the cross-section of coil 132 can have a hexagonal shape.

[0186] Coil 132 may include a plurality of coils 132a, 132b, 132c, and 132d. Each of the plurality of coils 132a, 132b, 132c, and 132d may be wound around a plurality of teeth 131b1, 131b2, 131b3, and 131b4 respectively. The plurality of coils 132a, 132b, 132c, and 132d may be formed in an even number. The plurality of coils 132a, 132b, 132c, and 132d may be spaced apart from each other circumferentially. The plurality of coils 132a, 132b, 132c, and 132d may be arranged symmetrically with reference to the center of the outer stator 131. The plurality of coils 132a, 132b, 132c, and 132d may be arranged radially with reference to the center of the outer stator 131. This improves the stability of the axial reciprocating motion of the inner stator 134 and the piston 150.

[0187] A plurality of coils 132a, 132b, 132c, and 132d can be arranged symmetrically with respect to the center of piston 150. The circumferential spacing and / or angle of each coil 132a, 132b, 132c, and 132d can be the same. Each coil 132a, 132b, 132c, and 132d can generate magnetic flux in a direction opposite to that of its circumferentially adjacent coil. Thus, the inner stator 134 and piston 150 can reciprocate stably along the axial direction.

[0188] The plurality of coils 132a, 132b, 132c, and 132d may include a first coil 132a, a second coil 132b circumferentially separated from the first coil 132a, a third coil 132c circumferentially separated from the second coil 132b, and a fourth coil 132d circumferentially separated from the third coil 132c. Each of the first coils 132a to the fourth coils 132d may be wound around a first tooth 131b1 to a fourth tooth 131b4, respectively. The first coil 131a and the third coil 131c may be wound in the same direction as each other. The first coil 131a and the third coil 131c may generate magnetic flux in the same direction. The first coil 131a may be wound in a different direction from the adjacent second coil 131b and the fourth coil 131d. The first coil 131a may generate magnetic flux in a different direction from the adjacent second coil 131b and the fourth coil 131d.

[0189] like Figure 7 As shown, when current flows through the first coil 131a and the second coil 131b, magnetic flux is formed along the direction that sequentially passes through the first tooth 131b1, the stator core 131a, and the second tooth 131b2. In this case, the inner stator 134 can move forward. "Forward" can refer to... Figure 7 The upward direction is the reference point.

[0190] When the current flows in the opposite direction, the magnetic flux is formed along the direction that sequentially passes through the second tooth 131b2, the stator core 131a, and the first tooth 131b1. In this case, the inner stator 134 can move rearward. "Rearward" can refer to... Figure 7 The downward direction is the reference point.

[0191] The embodiments described in this specification are illustrated using an example of four coils 132a, 132b, 132c, and 132d, but this is not a limitation. The number of coils 132a, 132b, 132c, and 132d can vary in many ways.

[0192] The inner stator 134 can be disposed inside the outer stator 131. The inner stator 134 can be coupled to the outer peripheral surface of the piston 150. The inner stator 134 can be coupled to the outer peripheral surface of the piston 150. The inner stator 134 can be formed into an annular shape. The inner stator 134 can be formed into a cylindrical shape with openings at the top and bottom.

[0193] The inner stator 134 can be a magnetic material. The inner stator 134 can reciprocate axially through electromagnetic interaction with the coil 132. Specifically, when current is applied to the coil 132, a magnetic flux is formed in the outer stator 131, thereby allowing the inner stator 134 to reciprocate axially. In this specification, "axial" refers to... Figure 2The direction of piston movement is based on the reference point. Figure 6 The vertical direction is the reference point.

[0194] The inner stator 134 can be opposite to the magnet 135. The axial length of the inner stator 134 can correspond to the axial length of the magnet 135. This maximizes the magnetic interaction efficiency between the inner stator 134 and the magnet 135. The inner stator 134 can also be opposite to the dummy pole 136. The axial length of the inner stator 134 can be equal to or less than the axial length of the dummy pole 136. Through the magnet 135, the inner stator 134 can... Figure 9 That will reset it to its initial position. This will be explained later.

[0195] Magnet 135 can be disposed on the outer stator 131. Magnet 135 can be disposed on the toothed shoe 131c of the outer stator 131. Magnet 135 can be disposed on the inner side of the toothed shoe 131c of the outer stator 131. Magnet 135 can be disposed in front of or behind the dummy pole 136. Magnet 135 can be in contact with the dummy pole 136. Magnet 135 can be opposite to the inner stator 134. Magnet 135 can overlap with the inner stator 134 in the radial direction.

[0196] The axial length of magnet 135 can correspond to the axial length of inner stator 134. The axial length of magnet 135 can be equal to or less than the axial length of dummy pole 136. The circumferential length of magnet 135 can correspond to the circumferential length of toothed shoe 131c. The radial thickness or length of magnet 135 can correspond to the radial thickness or length of dummy pole 136.

[0197] Magnet 135 may include a plurality of magnets 135a, 135b, 135c, and 135d. The plurality of magnets 135a, 135b, 135c, and 135d may be an even number. The plurality of magnets 135a, 135b, 135c, and 135d may have the same polarity. This prevents operator error that may occur when the plurality of magnets 135a, 135b, 135c, and 135d are arranged in the plurality of teeth 131c1, 131c2, 131c3, and 131c4.

[0198] Each of the plurality of magnets 135a, 135b, 135c, and 135d can be disposed in the first tooth portion 131c1 to the fourth tooth portion 131c4, respectively. Specifically, the plurality of magnets 135a, 135b, 135c, and 135d may include a first magnet 135a disposed in the first toothed shoe 131c1, a second magnet 135b disposed in the second toothed shoe 131c2, a third magnet 135c disposed in the third toothed shoe 131c3, and a fourth magnet 135d disposed in the fourth toothed shoe 131c4. This improves the stability of the magnetic interaction between the magnet 135 and the piston 150.

[0199] The first magnet 135a can be disposed on the inner side 131c11 of the first toothed shoe 131c1. The first magnet 135a can be disposed in the front region of the inner side 131c11 of the first toothed shoe 131c1. The first magnet 135a can be disposed in front of the first dummy pole 1361. The first magnet 135a can be disposed in a symmetrical position with reference to an axis passing through the center of the third magnet 135c and the outer stator 131. Thus, the efficiency of the magnetic interaction between the magnet 135 and the piston 150 can be improved while using a smaller amount of magnet 135. One embodiment of this specification is described with the first magnet 135a adjacent to the first dummy pole 1361, but it is not limited thereto; the first magnet 135a can also be separated from the first dummy pole 1361.

[0200] The second magnet 135b can be disposed on the inner side 131c21 of the second toothed shoe 131c2. The second magnet 135b can be disposed in the rear region of the inner side 131c21 of the second toothed shoe 131c2. The second magnet 135b can be disposed in the rear region of the second dummy pole 1362. The second magnet 135b can be disposed in a symmetrical position with reference to an axis passing through the center of the fourth magnet 135d and the outer stator 131. One embodiment of this specification is described with the second magnet 135b adjacent to the second dummy pole 1362, but it is not limited thereto; the second magnet 135b can also be spaced apart from the second dummy pole 1362.

[0201] The third magnet 135c can be disposed on the inner side 131c31 of the third toothed shoe 131c3. The third magnet 135c can be disposed in the front region of the inner side 131c31 of the third toothed shoe 131c3. The third magnet 135c can be disposed in the front region of the third dummy pole 1363. The third magnet 135c can be disposed in a symmetrical position with reference to an axis passing through the center of the first magnet 135a and the outer stator 131. An embodiment of this specification is described with the third magnet 135c adjacent to the third dummy pole 1363, but it is not limited thereto; the third magnet 135c can also be separated from the third dummy pole 1363.

[0202] The fourth magnet 135d can be disposed on the inner side 131c41 of the fourth toothed shoe 131c4. The fourth magnet 135d can be disposed in the rear region of the inner side 131c41 of the fourth toothed shoe 131c4. The fourth magnet 135d can be disposed in the rear region of the fourth dummy pole 1364. The fourth magnet 135d can be disposed in a symmetrical position with reference to an axis passing through the center of the second magnet 135b and the outer stator 131. One embodiment of this specification is described with the fourth magnet 135d adjacent to the fourth dummy pole 1364, but it is not limited thereto; the fourth magnet 135d can also be spaced apart from the fourth dummy pole 1364.

[0203] The embodiments described in this specification are illustrated using an example of four magnets 135a, 135b, 135c, and 135d, but this is not a limitation. The number of magnets 135a, 135b, 135c, and 135d can vary, such as two or six.

[0204] The virtual pole 136 can be disposed on the outer stator 131. The virtual pole 136 can be disposed on the toothed shoe 131c of the outer stator 131. The virtual pole 136 can be disposed on the inner side of the toothed shoe 131c of the outer stator 131. The virtual pole 136 can be disposed in front of or behind the magnet 135. The virtual pole 136 can be in contact with the magnet 135. The virtual pole 136 can be opposite to the inner stator 134. The virtual pole 136 and the inner stator 134 can overlap radially. The virtual pole 136 can be a magnetic material. The virtual pole 136 can be formed separately from the outer stator 131 and disposed on the outer stator 131, but the virtual pole 136 can also be integrally formed with the outer stator 131. Specifically, the virtual pole 136 is formed separately from the toothed shoe 131c of the outer stator 131 and disposed on the inner side of the toothed shoe 131c. Alternatively, the virtual pole 136 can be formed integrally with the inner side of the toothed shoe 131c of the outer stator 131. This reduces the additional cost of separately forming the virtual pole 136 and combining it with the toothed shoe 131c.

[0205] The axial length of the virtual pole 136 can correspond to the axial length of the inner stator 134. The axial length of the virtual pole 136 can be equal to or longer than the axial length of the magnet 135. Therefore, the efficiency of the magnetic interaction between the virtual pole 136 and the piston 150 can be improved while using a smaller amount of magnet 135. The circumferential length of the virtual pole 136 can correspond to the circumferential length of the toothed shoe 131c. The radial thickness of the virtual pole 136 can correspond to the radial thickness of the magnet 135.

[0206] Therefore, by using fewer magnets 135 than existing linear compressor drive units, the amount of coil 132 can be increased, thereby reducing the outer diameter of drive unit 130 and lowering product cost.

[0207] The virtual pole 136 may include a plurality of virtual poles 1361, 1362, 163, and 1364. The plurality of virtual poles 1361, 1362, 163, and 1364 may be an even number. Each of the plurality of virtual poles 1361, 1362, 163, and 1364 may be respectively configured in the first tooth portion 131c1 to the fourth tooth portion 131c4. Specifically, the plurality of virtual poles 1361, 1362, 163, and 1364 may include a first virtual pole 1361 configured in the first toothed shoe 131c1, a second virtual pole 1362 configured in the second toothed shoe 131c2, a third virtual pole 1363 configured in the third toothed shoe 131c3, and a fourth virtual pole 1364 configured in the fourth toothed shoe 131c4.

[0208] The first dummy pole 1361 can be disposed on the inner surface 131c11 of the first toothed shoe 131c1. The first dummy pole 1361 can be disposed in the rear region of the inner surface 131c11 of the first toothed shoe 131c1. The first dummy pole 1361 can be disposed behind the first magnet 135a. The first dummy pole 1361 and the third dummy pole 1363 can be disposed symmetrically with respect to an axis passing through the center of the outer stator 131. One embodiment of this specification is described with the first dummy pole 1361 adjacent to the first magnet 135a, but it is not limited thereto; the first dummy pole 1361 can also be separated from the first magnet 135a. The first dummy pole 1361 can be formed separately from the first toothed shoe 131c1 and disposed on the inner surface 131c11 of the first toothed shoe 131c1, but the first dummy pole 1361 can also be integrally formed with the inner surface 131c11 of the first toothed shoe 131c1.

[0209] The second virtual pole 1362 can be disposed on the inner side 131c21 of the second toothed shoe 131c2. The second virtual pole 1362 can be disposed in the front region of the inner side 131c21 of the second toothed shoe 131c2. The second virtual pole 1362 can be disposed in front of the second magnet 135b. The second virtual pole 1362 and the fourth virtual pole 1364 can be disposed symmetrically with respect to an axis passing through the center of the outer stator 131. One embodiment of this specification is described with the second virtual pole 1362 adjacent to the second magnet 135b, but this is not a limitation; the second virtual pole 1362 can also be separated from the second magnet 135b. The second virtual pole 1362 can be formed separately from the second toothed shoe 131c2 and disposed on the inner side 131c21 of the second toothed shoe 131c2, but the second virtual pole 1362 can also be integrally formed with the inner side 131c21 of the second toothed shoe 131c2.

[0210] The third virtual pole 1363 can be disposed on the inner surface 131c31 of the third toothed shoe 131c3. The third virtual pole 1363 can be disposed in the rear region of the inner surface 131c31 of the third toothed shoe 131c3. The third virtual pole 1363 can be disposed behind the third magnet 135c. The third virtual pole 1363 and the first virtual pole 1361 can be disposed symmetrically with respect to an axis passing through the center of the outer stator 131. An embodiment of this specification is described with the third virtual pole 1363 adjacent to the third magnet 135c, but it is not limited thereto; the third virtual pole 1363 can also be separated from the third magnet 135c. The third virtual pole 1363 can be formed separately from the third toothed shoe 131c3 and disposed on the inner surface 131c31 of the third toothed shoe 131c3, but the third virtual pole 1363 can also be integrally formed with the inner surface 131c31 of the third toothed shoe 131c3.

[0211] The fourth virtual pole 1364 can be disposed on the inner surface 131c41 of the fourth toothed shoe 131c4. The fourth virtual pole 1364 can be disposed in the front region of the inner surface 131c41 of the fourth toothed shoe 131c4. The fourth virtual pole 1364 can be disposed in front of the fourth magnet 135d. The fourth virtual pole 1364 and the second virtual pole 1362 can be disposed symmetrically with respect to an axis passing through the center of the outer stator 131. One embodiment of this specification is described with the fourth virtual pole 1364 adjacent to the fourth magnet 135d, but this is not a limitation; the fourth virtual pole 1364 can also be separated from the fourth magnet 135d. The fourth virtual pole 1364 can be formed separately from the fourth toothed shoe 131c4 and disposed on the inner surface 131c41 of the fourth toothed shoe 131c4, but the fourth virtual pole 1364 can also be integrally formed with the inner surface 131c41 of the fourth toothed shoe 131c4.

[0212] The embodiments described in this specification are illustrated using an example of four virtual poles 1361, 1362, 1363, and 1364, but are not limited thereto. The number of virtual poles 1361, 1362, 1363, and 1364 can vary in various ways, such as two or six.

[0213] Reference Figure 8 The axial length O1 of the outer stator 131 can be greater than the sum of the axial length m1 of the magnet 135 and the axial length P1 of the dummy pole 136. In this case, the axial length I1 of the inner stator 134 can correspond to the axial length m1 of the magnet 135, and the axial length P1 of the dummy pole 136 can be greater than the axial length m1 of the magnet 135. Thus, the axial stroke of the inner stator 134 and the piston 150 can be increased while using less magnet 135.

[0214] The outer stator 131 is formed by stacking a plurality of core plates 131a1, 131a2, ..., 131an, thereby increasing the number of coils 132 by increasing the axial length of the outer stator 131, thus reducing the outer diameter of the drive unit 130 while maintaining the same output. Furthermore, reducing the outer diameter of the drive unit 130 reduces the vertical height of the linear compressor 100. Moreover, using one magnet and one dummy pole instead of two axially arranged magnets reduces the number of magnets compared to existing technologies, thereby lowering product costs.

[0215] Reference Figure 9 The axial length O2 of the outer stator 131 can correspond to the sum of the axial length m2 of the magnet 135 and the axial length P2 of the dummy pole 136. In this case, the axial length I2 of the inner stator 134 can correspond to the axial length m2 of the magnet 135 and / or the axial length P2 of the dummy pole 136, where the axial length m2 of the magnet 135 can correspond to the axial length P2 of the dummy pole 136.

[0216] By using one magnet and one dummy pole instead of two magnets arranged along the axis, the number of magnets can be reduced compared to existing technologies, thereby reducing the cost of the product.

[0217] Furthermore, assuming the same amount of magnets as in the prior art is used, even with the same amount of magnets, the amount of coil 132 can be increased by increasing the axial length of the outer stator 131. Therefore, the outer diameter of the drive unit 130 can be reduced while maintaining the same output. Additionally, the vertical height of the linear compressor 100 can be reduced by decreasing the outer diameter of the drive unit 130.

[0218] Reference Figure 10 The axial length O3 of the outer stator 131 can be less than the sum of the axial length m3 of the magnet 135 and the axial length P3 of the virtual pole 136. In this case, the axial length I3 of the inner stator 134 can correspond to the axial length m3 of the magnet 135 and / or the axial length P3 of the virtual pole 136, where the axial length m3 of the magnet 135 can correspond to the axial length P3 of the virtual pole 136.

[0219] By using one magnet and one dummy pole instead of two magnets arranged along the axis, the number of magnets can be reduced compared to existing technologies, thereby reducing the cost of the product.

[0220] Furthermore, assuming the same amount of magnets as in the prior art is used, even with the same amount of magnets, the amount of coil 132 can be increased by increasing the axial length of the outer stator 131. Therefore, the outer diameter of the drive unit 130 can be reduced while maintaining the same output. Additionally, the vertical height of the linear compressor 100 can be reduced by decreasing the outer diameter of the drive unit 130.

[0221] Reference Figure 11 The axial length O4 of the outer stator 131 can be greater than the sum of the axial length m4 of the magnet 135 and the axial length P4 of the dummy pole 136. In this case, the axial length I4 of the inner stator 134 can correspond to the axial length m4 of the magnet 135 and / or the axial length P4 of the dummy pole 136, where the axial length m4 of the magnet 135 can correspond to the axial length P4 of the dummy pole 136.

[0222] The outer stator 131 is formed by stacking a plurality of core plates 131a1, 131a2, ..., 131an. The number of coils 132 can be increased by increasing the axial length of the outer stator 131, thereby reducing the outer diameter of the drive unit 130 while maintaining the same output. Furthermore, the vertical height of the linear compressor 100 can be reduced by decreasing the outer diameter of the drive unit 130. In addition, using one magnet and one dummy pole instead of two axially arranged magnets reduces the number of magnets compared to existing technologies, thus lowering product costs.

[0223] Reference Figure 7 and Figure 12 The first magnet 135a has the same polarity as the second magnet 135b, while the first virtual pole 1361 and the second virtual pole 1362, which are magnetic bodies, can have polarities that are relatively different from those of the first magnet 135a and the second magnet 135b. For example, the first magnet 135a and the second magnet 135b can have N poles, and the first virtual pole 1361 and the second virtual pole 1362 can have S poles relatively.

[0224] Reference Figure 13 When current is supplied to coil 132 and a magnetic flux is formed in one direction in outer stator 131, inner stator 134... Figure 13 The reference point is to move to the left. In this case, a region of the inner stator 134 facing the first virtual pole 1361 and the first magnet 135a has an S pole, and another region of the inner stator 134 facing the second virtual pole 1362 and the second magnet 135b has an S pole. That is, towards the direction with lower magnetic energy (i.e., magnetic potential energy or magnetic resistance), i.e., towards... Figure 10The reciprocating centering force F1, which resets the inner stator 134 to the right, can act between the inner stator 134 and the magnet 135. This reciprocating centering force F1 can reset the inner stator 134 to the central region of the outer stator 131.

[0225] Reference Figure 14 When current is supplied to coil 132 and a magnetic flux is formed in the outer stator 131 in the other direction, the inner stator 134... Figure 14 The reference point is to move to the right. In this case, a region of the inner stator 134 facing the first virtual pole 1361 and the first magnet 135a has an N pole, and another region of the inner stator 134 facing the second virtual pole 1362 and the second magnet 135b has an S pole. That is, moving towards the direction with lower magnetic energy (i.e., magnetic potential energy or magnetic resistance), i.e., towards... Figure 10 The reciprocating centering force F2, which resets the inner stator 134 to the left, can act between the inner stator 134 and the magnet 135. This reciprocating centering force F2 can reset the inner stator 134 to the center region of the outer stator 131.

[0226] That is, when the inner stator 134 moves away from the central region of the outer stator 131, the reciprocating central force of the magnet 135, which aims to return the inner stator 134 to its original position in the central region of the outer stator 131, acts on the inner stator 134. This force can be referred to as a magnetic resonance spring. Through this magnetic resonance spring, the inner stator 134 and the piston 150 can resonate. In this case, the linear compressor 100 of one embodiment of this specification can be implemented by removing the resonance spring 118. Thus, the mechanical stress limitation and vibration distance constraint can also be eliminated by removing the mechanical resonance spring. By using lateral force, the frictional loss between the inner stator 134 and the outer stator 131 caused by the eccentricity of the inner stator 134 and the piston 150 can be reduced.

[0227] Another embodiment of the drive unit 130 in this specification may include an outer stator 131, a coil 132, an inner stator 134, a magnet 135, and a dummy pole. It can be understood that the detailed configuration of the drive unit 130 in another embodiment of this specification, not described below, is the same as the detailed configuration of the drive unit 130 in one embodiment of this specification.

[0228] In another embodiment of this specification, the dummy pole can be integrally formed with the outer stator 131. Specifically, the dummy pole can be integrally formed with the toothed shoe 131c of the outer stator 131. In this case, both the dummy pole and the outer stator 131 can be formed of a magnetic material.

[0229] That is, the toothed shoe 131c may include a step portion formed on the inner side, and the magnet 135 may be disposed on the step portion on the inner side of the toothed shoe 131c.

[0230] Specifically, refer to Figure 7 The toothed shoe 131c may include a first step portion 131c11 to a fourth step portion 131c41 respectively formed on the first inner surface 1361 to the fourth inner surface 1364. In this case, each of the first magnets 135a to the fourth magnets 135d may be respectively disposed on the first step portion 131c11 to the fourth step portion 131c41. Of course, in this case, the radial length of the toothed shoe 131c may correspond to the sum of the radial length of the toothed shoe 131c and the radial length of the dummy pole 136 in one embodiment of this specification.

[0231] In addition, the first step portion 131c11 can be formed in the front region of the first toothed shoe 131c1, the second step portion 131c21 can be formed in the rear region of the second toothed shoe 131c2, the third step portion 131c31 can be formed in the front region of the third toothed shoe 131c3, and the fourth step portion 131c41 can be formed in the rear region of the fourth toothed shoe 131c4.

[0232] In addition, the axial length of magnet 135 can be equal to or less than the axial length of the step portion.

[0233] According to another embodiment of the drive unit 130 in this specification, the virtual pole and the toothed shoe 131c are integrally formed, thereby improving manufacturing convenience.

[0234] Another embodiment of the drive unit 130 in this specification may include an outer stator 131, a coil 132, an inner stator 134, a magnet 135, and a dummy pole. It can be understood that the detailed configuration of another embodiment of the drive unit 130 not described below is the same as the detailed configuration of the drive unit 130 in one embodiment of this specification.

[0235] In another embodiment of this specification, the dummy pole can be integrally formed with the outer stator 131. Specifically, the dummy pole can be integrally formed with the toothed shoe 131c of the outer stator 131. The dummy pole and the outer stator 131 can be formed of a magnetic material. In this case, the dummy pole of one embodiment of this specification can be replaced by protrusions 1361, 1362, 1363, and 1364 of another embodiment of this specification. Specifically, the toothed shoe 131c may include a protrusion 136 formed on the inner side, and the magnet 135 may be disposed on the inner side of the toothed shoe 131c.

[0236] Reference Figure 7The toothed shoe 131c may include a first protrusion 1361 to a fourth protrusion 1364 protruding inward from a first inner side 131c11 to a fourth inner side 131c41, respectively. In this case, each of the first magnets 135a to the fourth magnets 135d may be disposed on the first inner side 131c11 to the fourth inner side 131c41, respectively. Of course, in this case, the radial lengths of the protrusions 1361, 1362, 1363, and 1364 may correspond to the radial length of the virtual pole 136 in one embodiment of this specification.

[0237] According to another embodiment of the drive unit 130 in this specification, the virtual pole and the toothed shoe 131c are integrally formed, thereby improving manufacturing convenience.

[0238] Figure 15 This is a schematic diagram illustrating a portion of the toothed shoe, magnet, and inner stator according to an embodiment of this specification. Figure 16 This is a schematic diagram illustrating a portion of the toothed shoe, dummy pole, and inner stator according to an embodiment of this specification. Figure 17 and Figure 18 This is a diagram illustrating a modified example of a virtual pole according to an embodiment of this specification. Figure 19 This is a table comparing the lateral force and back electromotive force of one embodiment of this specification.

[0239] Reference Figure 15 and Figure 16 In a linear compressor 100 according to one embodiment of this specification, the distance d1 between the magnet 135 and the inner stator 134 may be different from the distance d2 between the dummy pole 136 and the inner stator 134.

[0240] Therefore, in the event of eccentricity between the mover and stator due to tolerance, collision between the piston 150 and the cylinder 140 can be prevented by reducing the side force.

[0241] In the linear compressor 100 of the first and second embodiments of this specification, the distance d1 between the magnet 135 and the inner stator 134 can be smaller than the distance d2 between the dummy pole 136 and the inner stator 134. Specifically, the difference between the distance d2 between the dummy pole 136 and the inner stator 134 and the distance d1 between the magnet 135 and the inner stator 134 can be less than 0.2 mm. Preferably, the difference between the distance d2 between the dummy pole 136 and the inner stator 134 and the distance d1 between the magnet 135 and the inner stator 134 can be more than 0.1 mm and less than 0.2 mm. This is because when the difference between the distance d2 between the virtual pole 136 and the inner stator 134 and the distance d1 between the magnet 135 and the inner stator 134 is less than 0.1 mm, the reduction in lateral force is negligible. When the difference between the distance d2 between the virtual pole 136 and the inner stator 134 and the distance d1 between the magnet 135 and the inner stator 134 is 0.2 mm, the back electromotive force (BEMF) decreases. The radial thickness of the virtual pole 136 can be thinner than the radial thickness of the inner stator 134.

[0242] In the linear compressor 100 of the first embodiment of this specification, when the distance d1 between the magnet 135 and the inner stator 134 is 0.5 mm, the distance d2 between the virtual pole 136 and the inner stator 134 can be 0.6 mm.

[0243] In the linear compressor 100 of the second embodiment of this specification, when the distance d1 between the magnet 135 and the inner stator 134 is 0.5 mm, the distance d2 between the virtual pole 136 and the inner stator 134 can be 0.7 mm.

[0244] Reference Figure 17 and Figure 18 In a linear compressor 100 according to an embodiment of this specification, the distances d3 and d5 between the virtual pole 136 and the inner stator 134 in the central region of the virtual pole 136 may be different from the distances between the virtual pole 136 and the inner stator 134 in regions outside the central region of the virtual pole 136.

[0245] Therefore, in the event of eccentricity between the mover and stator due to tolerance, collision between the piston 150 and the cylinder 140 can be prevented by reducing the side force.

[0246] Reference Figure 17In the case of the linear compressor 100 of the third embodiment of this specification, the distance d3 between the virtual pole 136 and the inner stator 134 in the central region of the virtual pole 136 can be greater than the distance d4 between the virtual pole 136 and the inner stator 134 in regions outside the central region of the virtual pole 136. In this case, the virtual pole 136 may include a groove 1368 formed in the central region.

[0247] The angle formed between the two ends of the central region of the virtual pole 136 and the center or center of the inner stator 134 can be less than 30 degrees. For example, the angle formed between a straight line passing through one end of the central region of the virtual pole 136 and the center of the inner stator 134 and a straight line passing through the other end of the central region of the virtual pole 136 and the center of the inner stator 134 can be less than 30 degrees. This is because if the angle formed between the two ends of the central region of the virtual pole 136 and the center or center of the inner stator 134 exceeds 30 degrees, the back electromotive force decreases and the compression efficiency of the piston 150 decreases.

[0248] Reference Figure 18 In the case of the linear compressor 100 of the fourth embodiment of this specification, the distance d5 between the virtual pole 136 and the inner stator 134 in the central region of the virtual pole 136 can be smaller than the distance d6 between the virtual pole 136 and the inner stator 134 in regions outside the central region of the virtual pole 136. In this case, the virtual pole 136 may include a slot 1369 formed in a region outside the central region.

[0249] The angle formed between the two ends of the central region of the virtual pole 136 and the center or center of the inner stator 134 can be less than 30 degrees. For example, the angle formed between a straight line passing through one end of the central region of the virtual pole 136 and the center of the inner stator 134 and a straight line passing through the other end of the central region of the virtual pole 136 and the center of the inner stator 134 can be less than 30 degrees. This is because if the angle formed between the two ends of the central region of the virtual pole 136 and the center or center of the inner stator 134 exceeds 30 degrees, the back electromotive force decreases and the compression efficiency of the piston 150 decreases.

[0250] Reference Figure 19 The side force and back electromotive force of the linear compressor 100 of the prior art and the first to fourth embodiments of this specification will be described.

[0251] Here, Side force VP can refer to the lateral force of the virtual pole 136, Side force mid can refer to the lateral force in the central region between the virtual pole 136 and the magnet 135, Side force mP can refer to the lateral force of the magnet 135, and Bemf can refer to the back electromotive force. Additionally, Side force average and Side force deviation can refer to the average and deviation of the lateral force of the virtual pole 136, the lateral force in the central region between the virtual pole 136 and the magnet 135, and the lateral force of the magnet 135, respectively.

[0252] For example, the central region between the virtual pole 136 and the magnet 135 can refer to, in order to Figure 7 Based on this, the area where the first magnet 135a and the first dummy pole 1361 contact can also refer to the central area of ​​the space separating the first magnet 135a and the second dummy pole 1362.

[0253] It can be seen that when the distance between magnet 135 and inner stator 134 is 0.5mm, the distance between virtual pole 136 and inner stator 134 is also 0.5mm, the back electromotive force is 38V, the average side force is 25.03N, and the deviation of the side force is 9.41N.

[0254] As can be seen, in the case of the linear compressor 100 of the first embodiment of this specification, for example, when the distance d1 between the magnet 135 and the inner stator 134 is 0.5 mm and the distance d2 between the dummy pole 136 and the inner stator 134 is 0.6 mm, the back electromotive force is 36.5 V, the average side force is 19.38 N, and the deviation of the side force is 6.14 N. That is, it can be seen that compared with the case where the distance between the magnet 135 and the inner stator 134 is the same as the distance between the dummy pole 136 and the inner stator 134, the back electromotive force is slightly reduced, but the average and deviation of the side force are significantly reduced.

[0255] As can be seen, in the case of the linear compressor 100 of the second embodiment of this specification, for example, when the distance d1 between the magnet 135 and the inner stator 134 is 0.5 mm and the distance d2 between the dummy pole 136 and the inner stator 134 is 0.7 mm, the back electromotive force is 35 V, the average side force is 16.03 N, and the deviation of the side force is 4.55 N. That is, it can be seen that compared with the case where the distance between the magnet 135 and the inner stator 134 is the same as the distance between the dummy pole 136 and the inner stator 134, the back electromotive force is slightly reduced, but the average and deviation of the side force are significantly reduced. In addition, it can be seen that compared with the case of the linear compressor 100 of the first embodiment of this specification, the back electromotive force is reduced, and the average and deviation of the side force are further reduced.

[0256] As can be seen, in the case of the linear compressor 100 of the third embodiment of this specification, for example, when the distance d1 between the magnet 135 and the inner stator 134 is 0.5 mm, the distance d3 between the virtual pole 136 and the inner stator 134 in the central region of the virtual pole 136 is 0.6 mm, and the distance d4 between the virtual pole 136 and the inner stator 134 in the region outside the central region of the virtual pole 136 is 0.5 mm, the back electromotive force is 38.1 V, the average side force is 23.26 N, and the deviation of the side force is 7.55 N. That is, it can be seen that compared with the case where the distance between the magnet 135 and the inner stator 134 is the same as the distance between the virtual pole 136 and the inner stator 134, the back electromotive force is slightly reduced, but the average and deviation of the side force are significantly reduced.

[0257] As can be seen, in the case of the linear compressor 100 of the fourth embodiment of this specification, for example, when the distance d1 between the magnet 135 and the inner stator 134 is 0.5 mm, the distance d5 between the virtual pole 136 and the inner stator 134 in the central region of the virtual pole 136 is 0.5 mm, and the distance d6 between the virtual pole 136 and the inner stator 134 in the region outside the central region of the virtual pole 136 is 0.6 mm, the back electromotive force is 37.3 V, the average side force is 21.69 N, and the deviation of the side force is 8.36 N. That is, it can be seen that compared with the case where the distance between the magnet 135 and the inner stator 134 is the same as the distance between the virtual pole 136 and the inner stator 134, the back electromotive force is slightly reduced, but the average and deviation of the side force are significantly reduced.

[0258] At least one embodiment of the first to fourth embodiments of this specification can be combined. Specifically, the first embodiment of this specification can be combined with the third or fourth embodiment, the second embodiment can be combined with the third or fourth embodiment, the third embodiment can be combined with the first or second embodiment, and the fourth embodiment can be combined with the first or second embodiment.

[0259] For example, in the case of the first embodiment or the combination of the second and third embodiments, the distance d1 between the magnet 135 and the inner stator 134 can be less than the distance d2 between the virtual pole 136 and the inner stator 134, and the distance d3 between the virtual pole 136 and the inner stator 134 in the central region of the virtual pole 136 can be greater than the distance d4 between the virtual pole 136 and the inner stator 134 in the region outside the central region of the virtual pole 136.

[0260] For example, in the case of the first embodiment or the combination of the second and fourth embodiments, the distance d1 between the magnet 135 and the inner stator 134 can be less than the distance d2 between the virtual pole 136 and the inner stator 134, and the distance d5 between the virtual pole 136 and the inner stator 134 in the central region of the virtual pole 136 can be less than the distance d6 between the virtual pole 136 and the inner stator 134 in the region outside the central region of the virtual pole 136.

[0261] Figure 20 This is a perspective view of a drive unit according to another embodiment of this specification. Figure 21 This is an exploded perspective view of the drive unit according to another embodiment of this specification. Figure 22 This is a top view of a drive unit according to another embodiment of this specification. Figure 23 This is a bottom view of the drive unit according to another embodiment of this specification.

[0262] Reference Figure 1 and Figures 20 to 23 Another embodiment of the linear compressor 100 in this specification may include a frame 120, a drive unit 130, a cylinder 140, and a piston 150, but additional configurations are not excluded. It can be understood that the detailed configurations of the linear compressor 100 of this specification, including the frame 120, drive unit 130, cylinder 140, and piston 150, in another embodiment not described below, are the same as those in one embodiment of the linear compressor 100 in this specification.

[0263] The drive unit 130 can be a transverse flux type reciprocating motor in which the direction of the flux and the linear movement direction of the piston 150 form a right angle. The drive unit 130 in the embodiments of this specification can be referred to as a "transverse flux type reciprocating motor".

[0264] The drive unit 130 may include an outer stator 131, a coil 132, an inner stator 134, a magnet 135, and a dummy pole 136.

[0265] The outer stator 131 may include a stator core 131a, a tooth portion 131b, and a tooth shoe 131c.

[0266] In another embodiment of this specification, the tooth 131b, toothed shoe 131c, coil 132, magnet 135, and dummy pole 136 can each be formed from two.

[0267] The tooth portion 131b may include a first tooth portion 131b1 and a second tooth portion 131b2 extending inward toward the stator core 131a. The first tooth portion 131b1 and the second tooth portion 131b2 may be formed in symmetrical positions relative to each other, with reference to the central region of the outer stator 131. The first tooth portion 131b1 and the second tooth portion 131b2 may be formed in corresponding shapes. A first coil 132a may be wound around the first tooth portion 131b1, and a second coil 132b may be wound around the second tooth portion 131b2. The first coil 132a and the second coil 132b may be wound in different directions relative to each other.

[0268] The toothed shoe 131c may include a first toothed shoe 131c1 and a second toothed shoe 131c2 extending circumferentially from the inner end of the tooth portion 131b. The first toothed shoe 131c1 may extend circumferentially from the inner end of the first tooth portion 131b1. The second toothed shoe 131c2 may extend circumferentially from the inner end of the second tooth portion 131b2. The first toothed shoe 131c1 and the second toothed shoe 131c2 may be formed in symmetrical positions relative to the central region of the outer stator 131. The first toothed shoe 131c1 and the second toothed shoe 131c2 may be formed in corresponding shapes. The first toothed shoe 131c1 and the second toothed shoe 131c2 may face each other.

[0269] A first magnet 135a and a first dummy pole 1361 may be disposed on the inner side of the first toothed shoe 131c1. A second magnet 135a2 and a second dummy pole 1362 may be disposed on the inner side of the second toothed shoe 131c2.

[0270] The first magnet 135a can be disposed in front of the first dummy pole 1361 along the axial direction, and the second magnet 135b can be disposed behind the second dummy pole 1362 along the axial direction.

[0271] In another embodiment of the linear compressor 100 of this specification, the teeth 131b, toothed shoe 131c, coil 132, magnet 135, and dummy pole 136 are each formed in pairs, thereby improving manufacturing convenience compared to the drive unit 130 of the linear compressor 100 of one embodiment of this specification.

[0272] The foregoing embodiments or other embodiments of this specification are not mutually exclusive or distinct. Various configurations or functions of the foregoing embodiments or other embodiments of this specification may be used in combination or interchangeably.

[0273] For example, this means that configuration A as illustrated in a specific embodiment and / or the drawings can be combined with configuration B as illustrated in other embodiments and / or the drawings. That is, it means that even if the combination between the configurations is not directly described, they can be combined except where it is stated that they cannot be combined.

[0274] The detailed description above should not be construed as limiting in all respects, but rather as exemplary. The scope of this specification should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of this specification are included within its scope.

Claims

1. A linear compressor, wherein, including: a frame; an outer stator including a stator core disposed on the frame, a tooth portion extending inward from the stator core, and a tooth shoe extending in a circumferential direction at an inner side end of the tooth portion; a coil disposed on the tooth portion; a cylinder disposed on the frame; a piston disposed on an inner side of the cylinder; an inner stator coupled to an outer circumferential surface of the piston, which reciprocates in an axial direction by electromagnetic interaction with the coil; a magnet disposed on the tooth shoe, facing the inner stator; and a virtual pole disposed on the tooth shoe, disposed in front of or behind the magnet in an axial direction, facing the inner stator, and formed integrally with the outer stator, the outer stator includes a plurality of core plates stacked in an axial direction, a distance between the magnet and the inner stator is different from a distance between the virtual pole and the inner stator.

2. The linear compressor of claim 1, wherein a radial thickness of the virtual pole is thinner than a radial thickness of the magnet.

3. The linear compressor of claim 1, wherein a distance between the virtual pole and the inner stator is greater than a distance between the magnet and the inner stator.

4. The linear compressor of claim 3, wherein a difference between the distance between the virtual pole and the inner stator and the distance between the magnet and the inner stator is 0.1 mm or more and 0.2 mm or less.

5. The linear compressor of claim 1, wherein a distance between the virtual pole and the inner stator in a central region of the virtual pole is different from a distance between the virtual pole and the inner stator in a region other than the central region of the virtual pole.

6. The linear compressor of claim 5, wherein the distance between the virtual pole and the inner stator in the central region of the virtual pole is greater than the distance between the virtual pole and the inner stator in the region other than the central region of the virtual pole.

7. The linear compressor of claim 6, wherein the virtual pole includes a groove formed in the central region.

8. The linear compressor of claim 6, wherein an angle formed by both ends of the central region of the virtual pole and a center of the inner stator is 30 degrees or less.

9. The linear compressor of claim 5, wherein a distance between the virtual pole and the inner stator in a central region of the virtual pole is less than a distance between the virtual pole and the inner stator in a region other than the central region of the virtual pole.

10. The linear compressor of claim 9, wherein the virtual pole includes a groove formed in the region other than the central region.

11. The linear compressor of claim 9, wherein an angle formed by both ends of the central region of the virtual pole and a center of the inner stator is 30 degrees or less. including:

12. A linear compressor, wherein, a frame; an outer stator including a stator core disposed on the frame, a tooth portion extending inward from the stator core, and a tooth shoe extending in a circumferential direction at an inner side end of the tooth portion; a coil disposed on the tooth portion; a cylinder disposed on the frame; a piston disposed on an inner side of the cylinder; ​ an inner stator combined to an outer circumferential surface of the piston, reciprocating in an axial direction by electromagnetic interaction with the coil; a magnet disposed in the toothed shoe, facing the inner stator; and a virtual pole disposed in the toothed shoe, disposed in front of or behind the magnet in an axial direction, facing the inner stator, formed integrally with the outer stator; the outer stator includes a plurality of core plates stacked in an axial direction, a distance between the virtual pole and the inner stator in a central region of the virtual pole is different from a distance between the virtual pole and the inner stator in a region other than the central region of the virtual pole.

13. The linear compressor of claim 12, wherein a distance between the virtual pole and the inner stator in a central region of the virtual pole is greater than a distance between the virtual pole and the inner stator in a region other than the central region of the virtual pole.

14. The linear compressor of claim 13, wherein the virtual pole includes a slot formed in the central region.

15. The linear compressor of claim 13, wherein an angle formed by both ends of the central region of the virtual pole and a center of the inner stator is 30 degrees or less.

16. The linear compressor of claim 12, wherein a distance between the virtual pole and the inner stator in a central region of the virtual pole is less than a distance between the virtual pole and the inner stator in a region other than the central region of the virtual pole.

17. The linear compressor of claim 16, wherein the virtual pole includes a slot formed in a region other than the central region.

18. The linear compressor of claim 16, wherein an angle formed by both ends of the central region of the virtual pole and a center of the inner stator is 30 degrees or less.

19. The linear compressor of claim 12, wherein a distance between the virtual pole and the inner stator is greater than a distance between the magnet and the inner stator.

20. The linear compressor of claim 12, wherein a radial thickness of the virtual pole is thinner than a radial thickness of the magnet.

Images