WO2007046608A1

WO2007046608A1 - Linear compressor

Info

Publication number: WO2007046608A1
Application number: PCT/KR2006/004195
Authority: WO
Inventors: Jong Koo Lee; Gye Young Song
Original assignee: Lg Electronics Inc.
Priority date: 2005-10-17
Filing date: 2006-10-17
Publication date: 2007-04-26

Abstract

Disclosed related to a linear compressor preventing the damages and variations of the piston and the cylinder which are important components of the linear compressor, and improving the reliability of the linear compressor as the spring supporter bumps into the stator cover before the flange unit of the piston bumps into the cylinder when the piston is over-advanced as composing the protrusion protruded toward each other at least one of the stator cover and spring supporter.

Description

LINEAR COMPRESSOR

Technical Field

[1] The present invention relates to a linear compressor and, more particularly, to a linear compressor improving reliability of the linear compressor as preventing impacts between a piston and a cylinder by forming protrusions protruded toward each other at least on one of a stator cover and a spring supporter. Background Art

[2] In general, a linear compressor is an apparatus inhaling, compressing, and discharging fluid as reciprocating a piston rectilinearly in a cylinder with rectilinear driving force of a linear motor.

[3] FIG. 1 is a cross-sectional view illustrating the linear compressor according to the conventional art, FIG. 2 is a cross-sectional view illustrating a state that the piston of the linear compressor according to the conventional art is over- advanced, and FIG. 3 is a cross-sectional view illustrating a state that the piston of the linear compressor according to the conventional art is over-advanced during inserting a piston guide.

[4] The conventional linear compressor depicted in FIG. 1 comprises a shell 2 and a linear compressor unit compressing fluid as arranged in the shell 2.

[5] An intake 4 inhaling fluid is penetrated on a side of the shell 2, and the linear compression unit is elastically supported with a damper 6 installed at the shell 2.

[6] The linear compression unit is composed of a cylinder block 12 having a cylinder

10, a back cover 14 having a fluid suction pipe 15, a piston 16 arranged to be advanced into and reversed from the cylinder 10, a linear motor 20 driving the piston 16, and a discharge valve assembly 18 forming a compression chamber C adjacent to the piston 16 on the front of the cylinder 10 and discharging fluid compressed in the compression chamber C.

[7] The linear motor 20 is broadly composed of a stator and a rotor. The stator is composed of an outer stator 21, inner stator 22, and a coil 23 forming magnetic field, and the rotor is composed of a magnet 24 linearly moved by the magnetic force formed around the coil 23 and a magnet frame 25 on which the magnet is fixed.

[8] The cylinder block 12 is positioned on the front of the outer stator 21, and a stator cover 26 is equipped on the rear of the outer stator 21.

[9] The piston 16 is arranged as capable of being advanced into and reversed from the cylinder 10 as receiving the linear impetus of the magnet 24. The piston 16 is formed as a cylindrical shape that the rear part is opened and has a suction pipe inhaling fluid in the inside, and a flange unit 27 is formed on the rear of the piston 16 to be fixed on the magnet frame 25.

[10] A spring supporter 28 is coupled with the rear surface of the magnet frame 25 to be interlocked with the magnet frame 25, and a spring supporter 28 is positioned between the stator cover 26 and the back cover 14.

[11] A main spring supporting the rectilinear reciprocating movement of the piston 16 elastically is equipped on the spring supporter 28. The main spring is composed of a f irst main spring 30 equipped between the spring supporter 28 and the back cover 14, and a second main spring 32 equipped between the spring supporter 28 and the stator cover 26.

[12] Reference will now be made in detail as for the operation of the linear compressor according to the conventional art configured as above.

[13] When the linear motor is operated, the magnet 24 is reciprocated rectilinearly, and the piston 16 is reciprocated rectilinearly in the cylinder 10 as the rectilinear reciprocating movement of the magnet 24 is transferred to the piston 16 through the magnet frame 25.

[14] When the piston 16 is reciprocated rectilinearly in the cylinder 10, the fluid in the shell 2 is discharged out of the shell 2 through the discharge valve assembly 18 after compressed by the piston 16 in the cylinder 10 as inhaled through the fluid suction pipe 15 of the back cover 14.

[15] Here, in case of the basic model of the linear compressor according to the conventional art, when the piston 16 is over- advanced due to the problems generated on controlling the operation distance of the piston 16, and impact is generated at the part A between the stator cover 26 and the spring supporter 28 as depicted in FIG. 2, and thus the linear compressor is operated normally.

[16] On the other hand, in case of controlling the capacity of the linear compressor, the position of the piston 16 should be moved to reduce the volume of the compression unit C.

[17] To move the location of the piston 16 as depicted in FIG. 3, a piston guide 34 is inserted between the piston 16 and the magnet frame 25.

[18] At this time, the conventional linear compressor has a disadvantage in that impact is generated at the part B between the flange unit 27 of the piston 16 and the cylinder 10 when the piston 16 is over- advanced in case that the piston guide 34 is inserted.

[19] Therefore, the conventional linear compressor has a disadvantage in that problems on the operation of the linear compressor may be generated as the piston 16 which is an important part of the linear compressor and the cylinder 10 changed or damaged.

[20] Further, the conventional linear compressor has a disadvantage in that a lot of time and costs are needed to inspect reliability of the linear compressor, and the reliability inspection is needed in several as the impact places between the parts may be different in accordance with the models. Disclosure of Invention

Technical Problem

[21] The present invention is contrived to overcome the above-mentioned conventional problems, and an object of the present invention is to provide a linear compressor improving reliability as preventing the impacts between the piston and the cylinder out of controlling the location of the piston. Technical Solution

[22] The linear compressor according to an embodiment of the present invention to achieve the above-mentioned object comprises a linear motor composed of a rotor and a stator, a stator cover installed on the stator, and a spring supporter installed on the rotor and having a main spring supporting the advancing and reversing movement of the rotor. Further, protrusions protruded toward each other are arranged at least one of the stator cover and the spring supporter.

[23] The protrusions are arranged as plural on the surface toward the spring supporter from the stator cover.

[24] A hole is formed on the center of the stator cover for the rotor passes through, and the protrusions are formed around the hole.

[25] The protrusions are a part of the stator cover bended toward the spring supporter.

[26] The protrusions are arranged as plural on the surface toward the stator cover from the spring supporter.

[27] The linear compressor further comprises a cylinder block installed on the stator and having a cylinder, and a piston coupled with the rotor and advanced into and reversed from the cylinder by the rotor.

[28] A side of the piston is inserted into the cylinder, and the other side has a flange unit to be coupled with the rotor.

[29] The distance of front and rear direction between the stator cover and the spring supporter is shorter than the distance between the flange unit of the piston and the cylinder.

[30] A piston guide is equipped on the rear of the piston to control the first location of the piston.

[31] The stator includes an outer stator installed between the cylinder block and the stator cover, and an inner stator arranged as adjacent to the outer stator with a predetermined interval in the radius direction.

[32] Further, the linear compressor according to another embodiment of the present invention comprises a linear motor composed of a stator and a rotor, a stator cover installed on a side of the stator, a cylinder block installed on the other side of the stator and having a cylinder, a piston having a flange unit to be coupled with the rotor and having a piston advanced into and reversed from the cylinder by the rotor, and a spring supporter installed on the rotor and having a main spring supporting the advancing and reversing movement of the rotor. Further, the interval between the stator cover and the spring supporter is smaller than the interval between the flange unit of the piston and the cylinder.

[33] A piston guide is installed on the rear of the piston to control the first location of the piston.

[34] The stator includes an outer stator installed between the cylinder block and the stator cover, and an inner stator arranged adjacent to the outer stator with a predetermined interval in the radius direction.

Advantageous Effects

[35] The linear compressor according to the present invention configured as above has some advantages in that the variation and the damage of the piston and the cylinder which are important parts of the linear compressor are prevented and the reliability of the linear compressor is improved as the spring supporter and the stator cover are bumped each other before the flange unit of the piston bumps into the cylinder when the piston is over- advanced as composing the protrusions protruded toward each other at least on one of the stator cover and the spring supporter.

[36] Further, the linear compressor according to the present invention configured as above has an advantage in that the developing period of the linear compressor is reduced with the reduction of the time and the costs to inspect the reliability as the impact is always generated between the spring supporter and the stator cover and the bumping location is unified without any connection with the models in case of changing the model to control the capacity of the linear compressor.

[37] Further, the linear compressor according to the present invention configured as above has an advantage in that the impact between the piston and the cylinder is always prevented without any connection with the location of the piston as the interval between the flange unit of the piston and the cylinder is bigger than the interval between the stator cover and the spring supporter even though the piston guide is inserted into the rear of the piston.

[38] Furthermore, the linear compressor according to the present invention configured as above has some advantages in that the interference with other parts is prevented and planning is easy as a plurality of protrusions are formed adjacent to each other with a predetermined interval in the circumferential direction.

[39] Moreover, the linear compressor according to the present invention configured as above has an advantage in that the impact between the piston and the cylinder is always prevented without any connection with the location of the piston as the stator cover is formed as thick as the interval between the flange unit of the piston and the cylinder is bigger than the interval between the stator cover and the spring supporter.

Brief Description of the Drawings [40] FIG. 1 is a cross-sectional view illustrating a linear compressor according to the conventional art, [41] FIG. 2 is a cross-sectional view illustrating a state that a piston according to the conventional art is over-advanced, [42] FIG. 3 is a cross-sectional view illustrating a state that a piston is over-advanced during the insertion of a piston guide according to the conventional art, [43] FIG. 4 is a cross-sectional view of a linear compressor according to the first preferred embodiment of the present invention, [44] FIG. 5 is a plane view illustrating a stator cover according to the first preferred embodiment of the present invention, [45] FIG. 6 is a cross-sectional view illustrating a state that a piston according to the first preferred embodiment of the present invention is over-advanced, [46] FIG. 7 is a cross-sectional view illustrating a state that a piston according to the second preferred embodiment of the present invention is over- advanced, [47] FIG. 8 is a cross-sectional view illustrating a state that a piston according to the third preferred embodiment of the present invention is over-advanced. [48]

[49] <REFERENCE NUMERALS OF THE PRINCIPLE PARTS>

[50] 50: SHELL 51 : DAMPER

[51] 52: CYLINDER BLOCK 53: FLUID SUCTION PIPE

[52] 54: BACK COVER 55: CYLINDER

[53] 56: PISTON 57: INTAKE

[54] 58: SUCTION VALVE 59: DISCHARGE PIPE

[55] 60: LINEAR MOTOR 61 : OUTER STATOR

[56] 62: INNER STATOR 63: COIL

[57] 64: MAGNET 65: MAGNET FRAME

[58] 66: STATOR COVER 70: DISCHARGE UNIT

[59] 71 : INNER DISCHARGE COVER 72: DISCHARGE VALVE

[60] 73: OUTER DISCHARGE COVER 74: SILENCER

[61] 75: SILENCER BODY 76: LEAD-IN PIPE

[62] 77: SPRING SUPPORTER 78: FIRST MAIN SPRING

[63] 79: SECOND MAIN SPRING 80: PROTRUSION

[64] 82: PISTON GUIDE Best Mode for Carrying Out the Invention

[65] Reference will now be made in detail as for the various embodiments of the present invention with reference to the accompanying drawings.

[66] Reference will now be made in detail as for the preferred embodiments of the present invention with reference to the accompanying drawings.

[67] FIG. 4 is a cross-sectional view of a linear compressor according to the first preferred embodiment of the present invention, and FIG. 5 is a plane view illustrating a stator cover according to the first preferred embodiment of the present invention.

[68] The linear compressor according to the first embodiment of the present invention, as depicted in FIG. 4, comprises a shell 50, a linear compression unit compressing fluid as arranged in the inside of the shell 50, and a damper 51 supporting the linear compression unit elastically as arranged at the shell 50.

[69] The linear compression unit includes a cylinder block 52 arranged in the shell 50, a linear motor 60 generating driving force as fixed on the cylinder block 52, a back cover 54 having a fluid suction pipe 53, a cylinder 55 arranged in the cylinder block 52, a piston 56 arranged to be advanced into and reversed from the cylinder 55, and a discharge unit 70 installed on the front of the cylinder 55 to discharge fluid compressed in the cylinder 55. An intake 57 inhaling fluid is penetrated on a side of the shell 50.

[70] The linear motor 60 is broadly composed of a stator and a rotor. The stator is composed of an outer stator 61, an inner stator 62, and a coil 63 forming magnetic field, and the rotor is composed of a magnet 64 moved linearly by the magnetic field formed around the coil 63 and a magnet frame 65 on which the magnet 64 is fixed. A stator cover 66 is fixed on the outer stator 61 to cover a side of the outer stator 61.

[71] A side of the piston 56 is inserted into the cylinder 55, and the other side is coupled with the magnet frame 65 to be advanced and reversed by the linear motor 60. A flange unit 56a is protruded on the rear of the piston 56 to be fixed on the front of the magnet frame 65 in the radius direction. A suction pot 56b is formed to inhale fluid into the compression chamber C of the cylinder 55, and a suction valve 58 opening and shutting the suction pot 56b is equipped on the front of the piston 56.

[72] The discharge unit 70 is fixed on the cylinder block 52, and includes an inner discharge cover 71 having a discharge hole on a side, a discharge valve 72 opening and shutting the compression chamber C of the cylinder 55 as supported by a spring on the inner discharge cover 71, and a outer discharge valve 73 arranged on the outer side of the inner discharge cover 71 to form a predetermined space. A discharge pipe 59 is connected with the outer discharge cover 73 to lead the fluid discharged from the cylinder 55 to outside of the shell 50.

[73] Further, a silencer 74 reducing suction noise is installed on the space between the rear of the piston 56 and the fluid suction pipe 53 of the back cover 54. The silencer 74 is composed of a silencer body 75 arranged on the rear of the piston 56, and a lead-in pipe 76 inserted into the piston 56 as extended from the silencer body 75 with a long length.

[74] On the other hand, a spring supporter 77 having a main spring supporting the rotor and the movement of the piston 56 elastically is installed on the rear of the piston 56. The spring supporter 77 is interlocked with the piston 56 as coupled with the rear surface of the magnet frame 65.

[75] The main spring is composed of a first main spring 78 equipped on the space between the spring supporter 77 and the back cover 54, and a second main spring 79 equipped on the space between the spring supporter 77 and the stator cover 66. The first main spring 78 is arranged on the upper and the lower sides in the shell 59, and the second main spring 79 is arranged on the left and right sides.

[76] A fixing bolt-not illustrated- supporting the first main spring 78 as penetrated on the first main spring 78 is arranged on the stator cover 66. A supporter penetration hole 77a through which the fixing bolt-not illustrated- is penetrated is formed on the spring supporter 77, and a back cover penetration hole 54a through which the fixing bolt-not illustrated- passed through the spring supporter 77 and the first main spring 78 is formed on the back cover 54.

[77] The protrusion 80 is arranged at least on one of the stator cover 66 and the spring supporter 77 to bump the stator cover 66 into the spring supporter 77 before the flange unit 56a of the piston 56 bumps into the back end of the cylinder 55 when the piston 56 is over- advanced. The protrusion 80 may be arranged each of the stator cover 66 and the spring supporter 77, however it is limited that the protrusion is arranged on the stator cover 66 on the following for the convenience of describing.

[78] The stator cover 66 is formed as a rounded board having a hole 66a on the center through which the piston 56 and the magnet frame 65 pass as depicted in FIG. 5. Further, the protrusion 80 is formed as at least a part of the stator cover 66 is bended toward the spring supporter to be protruded toward the spring supporter 77. On the protruded amount of the protrusion 80, the interval between the stator cover 66 and the spring supporter 77 is smaller than the interval between the flange unit 56a of the piston 56 and the cylinder 55. Furthermore, the protrusion 82 is formed around the hole 66a, and formed as plural adjacent to the circumferential direction with a predetermined interval.

[79] Reference will now be made in detail as for the operation of a linear compressor according to the first preferred embodiment of the present invention configured as above.

[80] When the linear motor 60 is operated, the magnet 64 is reciprocated rectilinearly, and the piston 56 is reciprocated rectilinearly in the cylinder 55 as the reciprocating movement of the magnet 64 is transferred through the magnet frame 65.

[81] When the piston 56 is reciprocated rectilinearly in the cylinder 55, and the fluid in the shell is discharged to outside of the shell 50 through the inner and outer discharge covers 71 and 73 and the discharge pipe 59 after compressed by the piston 56 in the cylinder 55 as inhaled into the fluid suction pipe 53 of the back cover 54. At this time, the first main spring 78 is compressed as the spring supporter 77 is reversed with the piston 56 when the piston 56 is reversed, and the movement of the piston 56 is supported elastically as the first main spring 78 is restored elastically as the second main spring is compressed with the advancing of the spring supporter 77 when the piston 56 is advanced.

[82] On the other hand, FIG. 6 is a cross-sectional view illustrating a state that a piston is over- advanced.

[83] In case of a basic model of the linear compressor according to the present invention, impact is generated on the part B between the stator cover 66 and the spring supporter 77 as depicted in FIG. 6 as ploblems on controlling the operation distance of the piston 56 are generated when the piston 56 is over-advanced. That is, the spring supporter 77 bumps into the protrusion 80 of the stator cover 66 before the flange unit 56a of the piston 56 bumps into the cylinder 55 as the spring supporter 77 is advanced as interlocked when the piston 56 is over- advanced. Therefore, the impact of the piston 56 and the cylinder 55 which are important parts of the linear compressor.

[84] FIG. 7 is a cross-sectional view illustrating a state that a piston according to the second preferred embodiment of the conventional art is over-advanced.

[85] As the other organizations of the linear compressor according to the second preferred embodiment of the present invention depicted in FIG. 7 excepting the insertion of the piston guide 82 between the piston 56 and the magnet frame 65 is the same to the first preferred embodiment, the same reference numerals will be used and the same descriptions are omitted on the following.

[86] The capacity of the linear compressor is controlled with changing the fist location of the piston 56 as inserting the piston guide 82. Here, impact is generated on the part B' between the stator cover 66 and the spring supporter 77 as ploblems on controlling the operation distance of the piston 56 are generated when the piston 56 is over- advanced. That is, the spring supporter 77 bumps into the protrusion 80 of the stator cover 66 before the flange unit 56a bumps into the cylinder 55 without any connection with the insertion of the piston guide 82. Therefore, the time and the costs for reliability inspection is minimized as the bumping parts are unified due to the bumping part of the components is always between the stator cover 66 and the spring supporter 77 when the piston 56 is over-advanced. [87] FIG. 8 is a cross-sectional view illustrating a state that a piston according to the third preferred embodiment of the conventional art is over- advanced.

[88] The description is limited as the protrusion 80 is formed on the stator cover 66 on the first and second preferred embodiments, however, the protrusion is not formed on the stator cover 66, and the interval Ll between the stator cover 66 and the spring supporter 77 is always smaller than the interval L2 between the flange unit 56a of the piston 56 and the cylinder 55 under the state that the piston guide 82 is inserted as depicted in FIG. 8 in the third preferred embodiment of the present invention. That is, the interval Ll between the stator cover 66 and the spring supporter 77 may be reduced as forming the thickness of the stator cover 66 thicker.

[89] The same reference numerals are used as other organizations are the same to the second preferred embodiment, and the same descriptions are omitted.

[90] The linear compressor according to the present invention has been described with reference to the accompanying drawings as above, however, the present invention is not limited to the preferred embodiments and drawings released on the present description, and various changes by the present manufacturer are possible in the technique field of the invention. Industrial Applicability

[91] The linear compressor according to the present invention has some advantageous effects in that the damage and variation of the piston and the cylinder which are important components are prevented and the reliability of the linear compressor is improved as the spring supporter bumps into the stator cover before flange unit of the piston bumps into the cylinder as composing the protrusion protruded toward each other at least on one of the stator cover and t6he spring supporter when the piston is over- advanced.

[92] Further, the linear compressor according to the present invention has an advantageous effect in that the developing period becomes shorter as the time and costs for reliability inspection are reduced as the bumping parts is unified without connection with the models, as the impacts are always generated between the spring supporter and the stator cover even in the case of changing model to control the capacity of the linear compressor.

[93] Further, the linear compressor according to the present invention has an advantageous effect in that the impacts between the piston and the cylinder is always prevented without connection with the location of the piston as the interval between the flange unit of the piston and the cylinder is bigger than the interval between the stator cover and the spring supporter even though the piston guide is installed on the rear of the piston. [94] Furthermore, Further, the linear compressor according to the present invention has an advantageous effect in that the interference with other components is prevented and the manufacturing becomes easy as a plurality of protrusions is formed as adjacent to each other with a predetermined interval in the circumferential direction.

[95] Moreover, the linear compressor according to the present invention has an advantageous effect in that the impacts between the piston and the cylinder is always prevented without connection with the location of the piston as the stator cover is formed thicker to form the interval between the flange unit of the piston and the cylinder bigger than the interval between the stator cover and the spring supporter.

Claims

[ 1 ] A linear compressor comprising: a linear motor having a stator and a rotor; a stator cover installed on the stator; and a spring supporter installed on the rotor, and having main springs supporting the advancing and reversing movement of the rotor; wherein a protrusion protruded toward each other at least on one of the stator cover and the spring supporter. [2] The linear compressor according to claim 1, wherein the protrusion is arranged as plural on the surface toward the spring supporter from the stator cover. [3] The linear compressor according to claim 2, wherein a hole is formed on the center of the stator cover so that the rotor passes through the hole, and the protrusion is formed around the hole. [4] The linear compressor according to claim 2, wherein the protrusion is a side of the stator cover bended toward the spring supporter. [5] The linear compressor according to claim 1, wherein the protrusion is arranged as plural on the surface toward the stator cover from the spring supporter. [6] The linear compressor according to claim 1, wherein the linear compressor further comprises a cylinder block installed on the stator and having a cylinder, and a piston coupled with the rotor and advanced into and reversed from the cylinder. [7] The linear compressor according to claim 6, wherein a flange unit is formed to insert a side of the piston into the cylinder, and to couple the other side with the rotor. [8] The linear compressor according to claim 7, wherein the front and rear interval between the stator cover and the spring supporter is smaller than the interval between the flange unit of the piston and the cylinder. [9] The linear compressor according to claim 1, wherein a piston guide is equipped on the rear of the piston to control the initial location of the piston. [10] The linear compressor according to claim 1, wherein the stator includes an outer stator installed between the cylinder block and the stator cover, and an inner stator arranged adjacent to the outer stator with a predetermined interval in the radius direction. [11] A linear compressor comprising: a linear motor having a stator and a rotor; a stator cover installed on a side of the stator; a cylinder block installed on the other side of the stator, and having a cylinder; a piston advanced into and reversed from the cylinder by the rotor as a flange unit which the rotor is coupled with is formed; and a spring supporter installed on the rotor and having main springs supporting the advancing and reversing movement of the rotor, wherein the interval between the stator cover and the spring supporter smaller than the interval between the flange unit of the piston and the cylinder. [12] The linear compressor according to claim 11, wherein a piston guide controlling the initial location of the piston is equipped on the rear of the piston. [13] The linear compressor according to claim 11, wherein the stator includes an outer stator installed between the cylinder block and the stator cover, and an inner stator arranged adjacent to the outer stator with a predetermined interval in the radius direction.