CN214533420U - Piston and linear compressor - Google Patents

Abstract

The utility model provides a piston and a linear compressor, wherein the piston comprises a piston body, a first air passage, a second air passage, a first air valve, a second air valve and a pneumatic shaft sleeve; an air cavity is constructed in the piston body; the first end of the first air passage and the first end of the second air passage are both communicated with the air cavity, the second end of the first air passage is formed at one end of the piston body, and the second end of the second air passage is formed at the other end of the piston body; the pneumatic shaft sleeve is sleeved on the side wall of the piston body, the air cavity is communicated with the inner side face of the pneumatic shaft sleeve, and a plurality of throttling air holes are formed in the side wall of the pneumatic shaft sleeve. The utility model discloses a piston contactless operation in the cylinder has reduced linear compressor's axial dimensions by a wide margin, has reduced the clearance that high-pressure gas produced between cylinder and piston and has revealed, has promoted linear compressor's efficiency effectively.

Description

Piston and linear compressor

Technical Field

The utility model relates to a compressor technical field especially relates to a piston and linear compressor.

Background

In the field of low-temperature technology, alternating flow refrigerators such as Stirling refrigerators, pulse tube refrigerators, thermoacoustic refrigerators and the like mainly produce cold by utilizing periodic expansion and compression of gas. The compressor of the alternating flow refrigerator is mainly a valveless linear compressor which is used as a pressure wave generator of the alternating flow refrigerator to realize the periodic compression and expansion of gas in the refrigerator. The linear compressor is directly driven by a linear motor to eliminate a crank link mechanism on the traditional reciprocating piston type compressor, reduce a motion conversion device and greatly improve the efficiency of the compressor, thereby obtaining wide attention and application.

At present, a pressure wave generator of an alternating flow refrigerator is widely applied by adopting a moving coil type or moving magnet type linear oscillation motor, the moving magnet type linear oscillation motor is a magnetic circuit structure that a magnetic conductive material is arranged on the circumference of an excitation coil to form a cylindrical air gap concentric with the excitation coil, the air gap is formed by a cylindrical stator, and a cylindrical permanent magnet magnetized in the radial direction reciprocates in the air gap, so that the moving magnet type linear motor has the advantages of small magnetic circuit loss, large specific thrust and the like.

For the low-temperature valveless linear compressor driven by the cylindrical linear oscillating motor, the resonant plate springs are mostly arranged on two sides of the linear compressor, and the resonant plate springs on the two sides support the reciprocating motion of the piston in the cylinder, so that the piston of the linear compressor and the cylinder realize the non-contact operation. Since the resonant plate springs are arranged on both sides of the linear compressor, an axial space at least longer than the running distance of the resonant plate springs needs to be reserved on both sides of the linear compressor, which results in a large size of the linear compressor.

Meanwhile, the linear compressor is limited by the influence of part processing precision and worker installation precision, and in order to ensure that a piston on the linear compressor and a cylinder operate in a non-contact manner completely, the fit clearance between the cylinder and the piston is large, so that gas leakage between a compression cavity and a backpressure cavity of the compressor is serious, the pressure ratio of the refrigerator cannot be further improved, but the fit clearance between the cylinder and the piston is reduced in order to reduce the gas leakage, and the assembly difficulty of the linear compressor is caused.

SUMMERY OF THE UTILITY MODEL

The utility model provides a piston and linear compressor for the resonant panel spring that the piston in solving current linear compressor can only arrange through linear compressor both sides provides the motion and supports, influences linear compressor's size, is unfavorable for improving linear compressor's the problem of compressing the ratio.

The utility model provides a piston, include: the pneumatic piston comprises a piston body, a first air passage, a second air passage, a first air valve, a second air valve and a pneumatic shaft sleeve; an air cavity is constructed in the piston body; the first end of the first air passage and the first end of the second air passage are both communicated with the air cavity, the second end of the first air passage is formed at one end of the piston body, and the second end of the second air passage is formed at the other end of the piston body; the first air valve is arranged on the first air passage, and the second air valve is arranged on the second air passage; the pneumatic shaft sleeve is sleeved on the side wall of the piston body, the air cavity is communicated with the inner side face of the pneumatic shaft sleeve, and a plurality of throttling air holes are formed in the side wall of the pneumatic shaft sleeve.

According to the utility model provides a pair of piston, the air vent has been constructed on the chamber wall of air cavity, the air vent with the medial surface intercommunication of pneumatic axle sleeve, the lateral surface of pneumatic axle sleeve flushes in or is higher than the side of piston body.

According to the utility model provides a pair of piston, first pneumatic valve with the second pneumatic valve is the check valve, first pneumatic valve is used for controlling the air current to follow directionally first pneumatic channel lets in to in the air cavity, the second pneumatic valve is used for controlling the air current to follow directionally the second pneumatic channel lets in to in the air cavity.

According to the utility model provides a pair of piston, pneumatic axle sleeve with the coaxial arrangement of piston body, the throttle gas pocket is followed pneumatic axle sleeve radially follows pneumatic axle sleeve's medial surface extends to pneumatic axle sleeve's lateral surface, the aperture of throttle gas pocket is 0.001-1000 mu m.

According to the utility model, the other end of the piston body is provided with the connecting seat; and/or, the piston body comprises a first segment and a second segment; the first segment is coaxially connected with the second segment; the pneumatic shaft sleeve is coaxially sleeved on the side wall of at least one of the first section and the second section.

The utility model also provides a linear compressor, including shell and core, place in the cavity of shell in the core, the core includes stator, active cell, flat spring and cylinder, stator, active cell and the coaxial setting of cylinder, stator and active cell constitute linear motor, still include the piston as above; the piston is slidably arranged in the cylinder, a compression cavity is formed between one end of the piston and the wall surface of the first side of the shell, a back pressure cavity is formed between the other end of the piston and the wall surface of the second side of the shell, an exhaust channel is arranged on the shell, and the exhaust channel is communicated with the compression cavity; the other end of the piston and one end of the rotor are both connected with the middle of the leaf spring, and the end part of the leaf spring is connected with one end of the stator.

According to the utility model provides a pair of linear compressor, the damping structure is equipped with in the backpressure intracavity, the one end of damping structure with flat spring's middle part is connected, the other end with the shell is connected.

According to the utility model provides a linear compressor, the vibration damping structure comprises a vibration damping spring and a vibration damping block; the damping spring is coaxially arranged with the piston; the damping block is arranged in the middle of the damping spring, one end of the damping spring is connected with the middle of the leaf spring, and the other end of the damping spring is connected with the shell.

According to the utility model provides a linear compressor, the shell is internally provided with the machine core; or two machine cores are arranged in the shell, are arranged along the axial direction of the piston and are arranged oppositely, and compression cavities on the two machine cores are communicated with the exhaust channel; an anti-collision device is arranged between one end of the cylinder, which is far away from the leaf spring, and the shell, a ventilation channel is constructed on the anti-collision device, and the compression cavity is communicated with the exhaust channel through the ventilation channel.

According to the utility model provides a linear compressor, the stator includes inner stator and outer stator, inner stator and outer stator coaxial arrangement, one of inner stator and outer stator is the iron core, the other one of inner stator and outer stator includes iron core and excitation winding; the rotor comprises a rotor framework and an annular permanent magnet; the annular permanent magnet is arranged on the rotor framework; one end of the rotor framework is connected with the middle part of the leaf spring and the connecting seat on the piston body respectively; the inner stator is coaxially arranged on the inner side of the annular permanent magnet, and the outer stator is coaxially arranged on the outer side of the annular permanent magnet; the inner stator and the outer stator form a cylindrical air gap, the annular permanent magnet is coaxially arranged in the cylindrical air gap, or one of the inner stator and the outer stator which is an iron core is connected with the annular permanent magnet.

According to the present invention, in a case where a cylindrical air gap is formed between the inner stator and the outer stator, the cylindrical air gap is in a straight-through shape along a moving direction of the piston; the excitation windings are circumferentially arranged on the inner stator or the outer stator, the rotor comprises a group of annular permanent magnets, and magnetic poles of the annular permanent magnets are arranged along the radial direction of the linear compressor; or, the outer side surface of the inner stator or the inner side surface of the outer stator is provided with a plurality of protrusions which are arranged along the circumference, each protrusion is wound with the excitation winding, the rotor comprises two groups of coaxially connected annular permanent magnets, and the magnetic poles of the two groups of annular permanent magnets are arranged along the radial direction of the linear compressor and are opposite in arrangement direction; or, in the case that a cylindrical air gap is formed between the inner stator and the outer stator, the inner stator is connected with the iron core at one end of the outer stator far away from the leaf spring, so that one end of the cylindrical air gap far away from the leaf spring is closed; the rotor comprises two groups of coaxially connected annular permanent magnets, and the magnetic poles of the two groups of annular permanent magnets are arranged along the radial direction of the linear compressor and are arranged in opposite directions.

The utility model provides a piston and a linear compressor, through arranging an air cavity, a first air passage, a second air passage, a first air valve, a second air valve and a pneumatic shaft sleeve on a piston body, in the process that the piston reciprocates in a cylinder of the linear compressor, high-pressure gas can enter the gas cavity through the first gas passage under the control of the first gas valve and then is introduced to the inner side surface of the pneumatic shaft sleeve through the gas cavity, because the side wall of the pneumatic shaft sleeve is provided with the plurality of throttling air holes, when high-pressure gas is discharged from the plurality of throttling air holes simultaneously, an annular pneumatic diaphragm can be formed between the outer side surface of the pneumatic shaft sleeve and the opposite wall surface of the cylinder, the pneumatic diaphragm can provide a better supporting effect for the reciprocating movement of the piston in the cylinder, ensure the non-contact operation of the piston in the cylinder and better prevent high-pressure gas in a compression cavity in the linear compressor from entering a back pressure cavity along an air gap between the piston and the cylinder; and along with the reciprocating motion of piston in the cylinder and the long-term work of pneumatic shaft sleeve, when the backpressure chamber leads to atmospheric pressure to increase because of its inside gaseous gradual accumulation, still can open the second pneumatic valve for the gas in the backpressure chamber enters into the air cavity through the second air flue, and continue to carry to pneumatic shaft sleeve, so, not only can provide the support for the reciprocating motion of piston in the cylinder based on pneumatic effect of pneumatic shaft sleeve, can equalize the atmospheric pressure inside compression chamber and the backpressure chamber again, prevent the unbalance of atmospheric pressure between the compression chamber that pneumatic shaft sleeve's long-term work leads to and the backpressure chamber, avoid causing the influence to the compression operation of linear compressor.

Therefore, the utility model discloses based on the improvement to the piston, overcome the problem that the piston in the current linear compressor can only provide the motion through the resonant plate spring that linear compressor both sides were arranged and support, realized the contactless operation of piston in the cylinder, reduced linear compressor's axial dimension by a wide margin, reduced the clearance that high-pressure gas produced between cylinder and piston and revealed, promoted linear compressor's efficiency effectively.

Drawings

In order to more clearly illustrate the technical solutions of the present invention or the prior art, the following briefly introduces the drawings required for the embodiments or the prior art descriptions, and obviously, the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic cross-sectional structural view of a piston provided by the present invention;

fig. 2 is one of schematic cross-sectional structural diagrams of the linear compressor provided by the present invention along the axial direction;

fig. 3 is a second schematic cross-sectional view of the linear compressor provided by the present invention along the axial direction;

fig. 4 is a third schematic view of a cross-sectional structure of the linear compressor provided by the present invention along the axial direction;

fig. 5 is an axial structural schematic view of the movement in fig. 4 provided by the present invention;

fig. 6 is a schematic cross-sectional view of the core of fig. 4 along a radial direction according to the present invention;

fig. 7 is a fourth schematic view of the cross-sectional structure of the linear compressor provided by the present invention along the axial direction;

fig. 8 is one of the schematic structural diagrams of the flat spring provided by the present invention;

fig. 9 is a second schematic structural view of the flat spring provided by the present invention;

fig. 10 is a third schematic structural view of a leaf spring provided by the present invention;

reference numerals:

1: a piston; 2: a stator; 3: a mover;

4: a leaf spring; 5: a cylinder; 6: a housing;

7: a compression chamber; 8: a back pressure chamber; 9: an exhaust passage;

10: a vibration reduction structure; 11: an anti-collision device; 12: a vent passage;

13: a first fixing member; 14: a second fixing member; 101: a piston body;

102: an air cavity; 103: a first air passage; 104: a second air passage;

105: a first air valve; 106: a second air valve; 107: a pneumatic shaft sleeve;

108: a vent hole; 1011: a first segment; 1012: a second segment;

1013: a connecting seat; 21: an inner stator; 22: an outer stator;

221: an iron core; 222: an excitation winding; 31: a rotor framework;

32: an annular permanent magnet; 110: a damping spring; 111: a vibration damping block;

100: a machine core.

Detailed Description

To make the objects, technical solutions and advantages of the present invention clearer, the drawings of the present invention are combined to clearly and completely describe the technical solutions of the present invention, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

A piston and a linear compressor according to the present invention will be described with reference to fig. 1 to 10.

As shown in fig. 1, the present embodiment provides a piston, the piston 1 including: the pneumatic piston comprises a piston body 101, a first air passage 103, a second air passage 104, a first air valve 105, a second air valve 106 and a pneumatic shaft sleeve 107; an air cavity 102 is formed in the piston body 101; the first end of the first air passage 103 and the first end of the second air passage 104 are both communicated with the air cavity 102, the second end of the first air passage 103 is formed at one end of the piston body 101, and the second end of the second air passage 104 is formed at the other end of the piston body 101; the first air valve 105 is arranged on the first air passage 103, and the second air valve 106 is arranged on the second air passage 104; the side wall of the piston body 101 is sleeved with a pneumatic shaft sleeve 107, the air cavity 102 is communicated with the inner side surface of the pneumatic shaft sleeve 107, and a plurality of throttling air holes are formed in the side wall of the pneumatic shaft sleeve 107. The first air valve 105 and the second air valve 106 shown in the present embodiment can be understood as a one-way valve or a reed valve that can be automatically opened or closed according to the change of the air pressure, and are not limited in particular.

Specifically, in the process that the piston 1 shown in this embodiment reciprocates in the cylinder 5 of the linear compressor, high-pressure gas can enter the air cavity 102 through the first air passage 103 under the control of the first air valve 105, and then enters the inner side surface of the pneumatic shaft sleeve 107 through the air cavity 102, because the side wall of the pneumatic shaft sleeve 107 is provided with the plurality of throttle holes, when the high-pressure gas is simultaneously discharged from the plurality of throttle holes, an annular pneumatic diaphragm can be formed between the outer side surface of the pneumatic shaft sleeve 107 and the opposite wall surface of the cylinder 5, and the pneumatic diaphragm can provide a good supporting effect for the reciprocating movement of the piston 1 in the cylinder 5, so as to ensure that the piston 1 operates without contact in the cylinder 5, and can better prevent the high-pressure gas in the compression cavity 7 in the linear compressor from entering the back pressure cavity 8 along an air gap between the piston 1 and the cylinder 5; along with the reciprocating motion of the piston 1 in the cylinder 5 and the long-term work of the pneumatic shaft sleeve 107, when the air pressure of the back pressure cavity 8 is increased due to the gradual accumulation of the air in the back pressure cavity 8, the second air valve 106 can be opened, so that the air in the back pressure cavity 8 enters the air cavity 102 through the second air passage 104 and is continuously conveyed to the pneumatic shaft sleeve 107, and thus, the reciprocating motion of the piston 1 in the cylinder 5 can be supported based on the pneumatic action of the pneumatic shaft sleeve 107, the air pressures in the compression cavity 7 and the back pressure cavity 8 can be balanced, the imbalance of the air pressure between the compression cavity 7 and the back pressure cavity 8 caused by the long-term work of the pneumatic shaft sleeve 107 is prevented, and the influence on the compression operation of the linear compressor is avoided.

Therefore, the utility model discloses based on to piston 1's improvement, overcome the problem that piston 1 in the current linear compressor can only provide the motion through the resonant plate spring that linear compressor both sides were arranged and support, realized the contactless operation of piston 1 in cylinder 5, reduced linear compressor's axial dimensions by a wide margin, reduced the clearance that high-pressure gas produced between cylinder 5 and piston 1 and revealed, promoted linear compressor's efficiency effectively.

As shown in fig. 1, the air chamber 102 shown in this embodiment is disposed to extend along the axial direction of the piston body 101, and the air chamber 102 may be specifically disposed in a cylindrical shape. A plurality of vent holes 108 are formed in the cavity wall surface of the air cavity 102, and each vent hole 108 extends in the radial direction of the piston body 101, and the vent holes 108 communicate with the inner side surface of the pneumatic sleeve 107. Here, a plurality of vent holes 108 may be disposed to be circumferentially distributed in each region corresponding to the inner side surface of the pneumatic sleeve 107, so as to ensure that the inner side surface of the pneumatic sleeve 107 can uniformly receive the high-pressure gas from the air cavity 102.

Meanwhile, the outer side surface of the pneumatic sleeve 107 can be arranged to be flush with or higher than the side surface of the piston body 101 in the embodiment, so that the contact friction between the outer side surface of the pneumatic sleeve 107 and the inner wall surface of the cylinder 5 on the linear compressor is reduced as much as possible.

It should be noted that the pneumatic sleeve 107 shown in the present embodiment has a hollow cylindrical shape, the pneumatic sleeve 107 is arranged coaxially with the piston body 101, the throttle holes extend from the inner side surface of the pneumatic sleeve 107 to the outer side surface of the pneumatic sleeve 107 in the radial direction of the pneumatic sleeve 107, the aperture of the throttle holes is specifically 0.001 to 1000 μm, and the throttle holes are uniformly densely distributed in each region on the side wall of the pneumatic sleeve 107. The pneumatic sleeve 107 may be a porous foamed metal member processed from metal powder or a metal mesh, a porous air-permeable ceramic member or a porous air-permeable plastic member processed from non-metal powder such as carbon powder, graphite powder, alumina powder, silica powder, engineering plastic powder, or a porous composite air-permeable member processed from a mixture of metal powder, metal mesh, and non-metal powder.

In addition, in order to improve the working performance of the piston 1, a wear-resistant self-lubricating coating can be coated on the side surface of the piston body 101, and the wear-resistant self-lubricating coating comprises the following componentsGraphite coating (GLC), polyether ether copper coating (PEEK), polyimide resin coating (PI), diamond-like carbon coating (DLC), Teflon coating (Teflon), molybdenum disulfide coating (MoS)₂) Tungsten disulfide coating (WS)₂) Graphite coating (C), chromium nitride Coating (CRN), titanium aluminum silicon nitride coating (TiAlSiN), titanium aluminum nitride coating (AlTiN), titanium nitride coating (TiN), and alumina ceramic coating (Al)₂O₃) And a phosphate coating (P) or a combination of at least two thereof.

As shown in fig. 1, the first air valve 105 and the second air valve 106 of the present embodiment are both one-way valves, the first air valve 105 is used for controlling the directional air flow from the first air passage 103 into the air cavity 102, and the second air valve 106 is used for controlling the directional air flow from the second air passage 104 into the air cavity 102.

Specifically, the first air valve 105 and the second air valve 106 shown in the present embodiment may be both specifically disposed in the air cavity 102, the first air valve 105 is located at the first end of the first air passage 103, and the second air valve 106 is located at the first end of the second air passage 104. In this way, when the piston 1 moves toward one side of the compression chamber 7 in the cylinder 5, as the air pressure in the compression chamber 7 increases, when the air pressure in the compression cavity 7 is higher than the air pressure in the air cavity 102, under the action of the pressure difference, high-pressure air continuously flows into the air cavity 102 through the first air valve 105 until the air pressure in the air cavity 102 and the air pressure in the compression cavity 7 are balanced, so that the air in the air cavity 102 can maintain higher pressure, when the gas in the gas chamber 102 flows to the inner side of the pneumatic sleeve 107 through the vent hole 108, a stable pneumatic diaphragm can be formed between the outer side surface of the pneumatic sleeve 107 and the opposite wall surface of the cylinder 5, to provide a better support for the reciprocating movement of the piston 1 in the cylinder 5 and to better prevent the high-pressure gas in the compression chamber 7 of the linear compressor from entering the back pressure chamber 8 along the air gap between the piston 1 and the cylinder 5.

Because the pneumatic diaphragm provides the supporting role in the reciprocating motion of piston 1, some gas can enter back pressure chamber 8 along the air gap between piston 1 and cylinder 5, along with the long-term work of pneumatic shaft sleeve 107, back pressure chamber 8 leads to atmospheric pressure increase because of the gradual accumulation of its inside gas, when atmospheric pressure in back pressure chamber 8 is greater than the atmospheric pressure in air cavity 102, under the effect of pressure differential, second pneumatic valve 106 opens automatically, make the gas in back pressure chamber 8 enter air cavity 102 through second air flue 104, can equalize the atmospheric pressure in compression chamber 7 and back pressure chamber 8 effectively, improve linear compressor's compression ratio.

As shown in fig. 1 and 2, in order to facilitate the connection of the piston 1 with the leaf spring 4 and the mover 3 of the linear compressor, the other end of the piston body 101 shown in the present embodiment is configured with a connection seat 1013.

Meanwhile, in order to facilitate the installation of the pneumatic sleeve 107, the piston body 101 shown in the present embodiment may be specifically configured as a first section 1011 and a second section 1012; the first section 1011 is coaxially connected with the second section 1012; the pneumatic bushing 107 is coaxially fitted on a sidewall of at least one of the first section 1011 and the second section 1012.

Specifically, in this embodiment, a first annular notch is formed in the side wall of the first section 1011, a second annular notch is formed in the side wall of the second section 1012, and under the condition that the first section 1011 and the second section 1012 are correspondingly butted, the first annular notch and the second annular notch are spliced to form an annular groove, and the pneumatic shaft sleeve 107 is embedded in the annular groove.

Meanwhile, the air chamber 102 and the second air passage 104 are configured at the first section 1011, the first air passage 103 is configured at the second section 1012, and the connecting seat 1013 is configured at an end of the first section 1011 away from the second section 1012.

The structure of the linear compressor will be described below specifically based on the piston 1 shown in the above-described embodiment.

Example 1

As shown in fig. 2, the present embodiment provides a linear compressor, which includes a housing 6 and a core 100, the core 100 is disposed in a cavity of the housing 6, the core 100 includes a stator 2, a mover 3, a leaf spring 4 and a cylinder 5, the stator 2, the mover 3 and the cylinder 5 are coaxially disposed, and the stator 2 and the mover 3 form a linear motor; further comprising a piston 1 as described above; the piston 1 is slidably arranged in the cylinder 5, a compression cavity 7 is formed between one end of the piston 1 and the wall surface of the first side of the shell 6, a back pressure cavity 8 is formed between the other end of the piston 1 and the wall surface of the second side of the shell 6, an exhaust channel 9 is arranged on the shell 6, and the exhaust channel 9 is communicated with the compression cavity 7; the other end of the piston 1 and one end of the rotor 3 are both connected with the middle part of the leaf spring 4, and the end part of the leaf spring 4 is connected with one end of the stator 2. The wall surface of the first side and the wall surface of the second side of the housing 6 are disposed opposite to each other on both sides of the cylinder 5.

Specifically, when the piston 1 moves towards one side of the back pressure chamber 8, the linear compressor sucks air from the outside through the exhaust passage 9, and the outside air enters the compression chamber 7 along the exhaust passage 9, in the process, the first air valve 105 is closed, and the pneumatic sleeve 107 forms a stable pneumatic diaphragm between the outer side surface of the pneumatic sleeve 107 and the opposite wall surface of the cylinder 5 based on the air supply effect of the air chamber 102, so as to provide a good supporting effect for the reciprocating movement of the piston 1 in the cylinder 5 and better prevent the air from flowing between the compression chamber 7 and the back pressure chamber 8 along the air gap between the piston 1 and the cylinder 5.

Accordingly, when the piston 1 moves toward the side of the compression chamber 7, the gas inside the compression chamber 7 is compressed for a short time to rapidly increase the gas pressure, and when the gas pressure inside the compression chamber 7 is higher than the gas pressure inside the gas chamber 102, the first gas valve 105 is opened, and the pneumatic sleeve 107 forms a relatively stable pneumatic diaphragm between the outer side surface of the pneumatic sleeve 107 and the opposite wall surface of the cylinder 5 based on the gas supply action of the gas chamber 102, so as to provide a relatively good support action for the reciprocating movement of the piston 1 inside the cylinder 5, and to relatively well prevent the gas from flowing between the compression chamber 7 and the back pressure chamber 8 along the air gap between the piston 1 and the cylinder 5. Wherein, in the process of compressing the gas by the piston 1, the high-pressure gas in the compression cavity 7 is gradually discharged from the discharge passage 9 again to realize the discharge of the linear compressor.

Because the pneumatic diaphragm provides the supporting function for the reciprocating movement of the piston 1 in the cylinder 5, a part of gas can enter the back pressure cavity 8 along the air gap between the piston 1 and the cylinder 5, along with the long-term work of the pneumatic shaft sleeve 107, the back pressure cavity 8 increases the gas pressure due to the gradual accumulation of the gas inside the back pressure cavity 8, when the gas pressure in the back pressure cavity 8 is greater than the gas pressure inside the gas cavity 102, under the action of the pressure difference, the second gas valve 106 is automatically opened, so that the gas in the back pressure cavity 8 enters the gas cavity 102 through the second gas passage 104, the gas pressures inside the compression cavity 7 and the back pressure cavity 8 can be effectively equalized, and the compression ratio of the linear compressor is greatly improved.

As shown in fig. 2, two cartridges 100 are disposed in the housing 6 shown in this embodiment, the two cartridges 100 are arranged along the axial direction of the piston 1 and are disposed in an opposite manner, and the compression chambers 7 on the two cartridges 100 are both communicated with the exhaust passage 9. Here, in the present embodiment, by providing two cores 100 facing each other, when the linear compressor is operated, the vibrations of the two cores 100 can be cancelled out each other, and the vibration damping effect on the housing 6 of the linear compressor can be effectively achieved.

It should be noted here that the flat spring 4 shown in the present embodiment may be provided in plural, and the plural flat springs 4 are sequentially connected in a stacked arrangement to constitute a resonant spring assembly. Wherein, a spring flat gasket is arranged between two adjacent layer springs 4.

The connection between the resonant spring assembly and the piston 1 shown in the present embodiment may be provided in various forms. For example: the middle part of the resonant spring assembly is connected with the other end of the piston 1, and each end part of the resonant spring assembly is connected with one end of the stator 2; alternatively, at least one end of the resonant spring assembly is connected to the other end of the piston 1, and the other end of the resonant spring assembly is connected to one end of the stator 2, which is not particularly limited herein.

Meanwhile, the flat spring 4 shown in the present embodiment includes elastic members distributed in the same plane or in the vicinity of the same plane, and the end portion of the flat spring 4 is a free end, and may be provided in plural. The elastic component can be a first combined shape formed by sequentially connecting a plurality of straight line segments and/or curve segments end to end, and two free ends are respectively arranged at two ends of the first combined shape; that is, the elastic member has two free ends, and the two free ends can be formed by connecting any straight line segment and any curved line segment in any bending mode.

Or, the elastic member may be a second combined shape in which one ends of a plurality of linear segments and/or curved segments are connected as a whole, and the other ends of the corresponding linear segments or curved segments in the second combined shape are respectively set as free ends; the elastic component has more than three free ends, and each free end is connected with the central part by any straight line segment or any curve segment in a random bending mode.

The resonant spring assembly shown in the present embodiment may be sequentially connected in a stacked arrangement using a plurality of plate springs 4 having the first combined shape or the second combined shape shown in the above-described embodiments. Of course, the resonant spring assembly may also combine the first and second combined shapes of the flat spring 4. Here, in this embodiment, based on the improved arrangement of the resonant spring assembly, only the resonant spring assembly needs to be arranged on one side of the linear compressor, so that the piston 1 can be driven by the linear motor to reciprocate in the cylinder 5, and the axial dimension of the linear compressor can be greatly reduced.

It should also be noted that the first combined shape may be formed by bending the spring wire material multiple times in the same plane, and obviously, the shape of each bending section of the first combined shape includes a straight section, a curved section and a combination thereof, and the cross section of the spring wire material may be circular, oval, square or triangular, and is not limited in particular. Thus, the combined shape of the leaf spring 4 obtained by bending may be "S" -type, "C" -type, "Z" -type, "L" -type, "ㄥ" -type, "V" -type, "U" -type, "angle" -type, "L" -type, "く" -type, "へ" -type, "J" -type, or the like.

As shown in fig. 8, the leaf spring 4 is formed in a first combined shape by bending a spring wire rod with a circular cross section for at least 6 times; the shape of the device comprises 5 sections of straight lines, 4 sections of connecting transition arcs (curve sections) and arc free ends which are positioned at the head end and the tail end and used for positioning and mounting; therefore, the free ends of the head end and the tail end of the leaf spring 4 are connected with the edge part of the stator 2, and the central position of the leaf spring 4 is connected with the corresponding end of the piston 1 so as to support the piston 1 to reciprocate in the cylinder 5. The specific manner of the leaf spring 4 shown in this embodiment is shown in fig. 5.

As shown in fig. 9, the leaf spring 4 is formed in a first combined shape by bending a spring wire rod with a circular cross section for at least 12 times; the shape of the device comprises 10 arc sections (curve sections), 1 central connecting section (straight section) and arc free ends which are positioned at the head end and the tail end and used for positioning and installation. Of course, the first combination shape shown in the present embodiment also includes other structural forms, which are not necessarily listed here.

Meanwhile, the flat spring 4 may also be a second combined shape in which one ends of a plurality of straight line segments or curved line segments are connected as a whole, and the other ends of the corresponding straight line segments or curved line segments in the second combined shape are respectively provided with free ends. Thus, the leaf springs 4 in this form are arranged radially and obviously comprise a plurality of free ends.

As shown in fig. 10, the leaf spring 4 is in a second combined shape, three curved segments in the leaf spring 4 are in a centrosymmetric arrangement structure, wherein the cross section of each curved segment is rectangular, one ends of the three curved segments are connected through a ring structure, the other ends of the three curved segments are set as corresponding free ends, the free ends are in a fan-ring structure, and a plurality of fixing holes are opened on the fan-ring structure. Thus, the ring structure of the leaf spring 4 in the central position can be connected to the respective end of the piston 1, while the sector ring structure corresponding to each radial end of the leaf spring 4 is connected to the corresponding stator 2 for supporting the piston 1 in a reciprocating movement inside the cylinder 5.

Further, as shown in fig. 2, a collision prevention device 11 is installed between one end of the cylinder 5 facing away from the leaf spring 4 and the housing 6, a vent passage 12 is formed in the collision prevention device 11, and the compression chamber 7 is communicated with the exhaust passage 9 through the vent passage 12.

It should be pointed out here that the impact protection 11 can be embodied as a cylindrical component arranged coaxially with the cylinder 5, which component is further preferably a teflon engineering plastic part, the ventilation channels 12 being distributed along the center axis of the teflon engineering plastic part. When the stroke of the piston 1 moving in the cylinder 5 is too large, the anti-collision device 11 can effectively buffer the piston 1 and prevent the piston 1 from directly impacting the shell 6.

Further, the stator 2 shown in the present embodiment includes an inner stator 21 and an outer stator 22, the inner stator 21 and the outer stator 22 are coaxially arranged, one of the inner stator 21 and the outer stator 22 is an iron core, and the other of the inner stator 21 and the outer stator 22 includes an iron core and an excitation winding; the mover 3 includes a mover frame 31 and an annular permanent magnet 32; the annular permanent magnet 32 is mounted on the mover frame 31; one end of the mover frame 31 is connected to the middle of the leaf spring 4 and the connecting seat 1013 on the piston body 101, respectively; the inner stator 21 is coaxially arranged at the inner side of the annular permanent magnet 32, and the outer stator 22 is coaxially arranged at the outer side of the annular permanent magnet 32; a cylindrical air gap is formed between the inner stator 21 and the outer stator 22, the annular permanent magnet 32 is coaxially arranged in the cylindrical air gap, or one of the inner stator 21 and the outer stator 22 which is an iron core is connected with the annular permanent magnet 32.

As shown in fig. 2, when a cylindrical air gap is formed between the inner stator 21 and the outer stator 22, the cylindrical air gap is straight along the moving direction of the piston 1. The excitation windings 222 are circumferentially arranged on the iron core 221 of the outer stator 22, the inner stator 21 is only provided with an iron core structure, and the excitation windings are not arranged on the inner stator 21. Meanwhile, the mover 3 includes a set of ring-shaped permanent magnets 32, and magnetic poles of the ring-shaped permanent magnets 32 are arranged in a radial direction of the linear compressor.

It should be noted that the excitation windings 222 shown in the present embodiment may also be arranged circumferentially on the core of the inner stator 21, the outer stator 22 is only provided with a core structure, and the excitation windings are not provided on the outer stator 22.

Meanwhile, the magnetic poles of the annular permanent magnet 32 shown in the embodiment are arranged along the radial direction of the linear compressor, and it can be understood that the magnetic pole inside the annular permanent magnet 32 is an N pole, and the magnetic pole outside the annular permanent magnet 32 is an S pole, or the magnetic pole inside the annular permanent magnet 32 is an S pole, and the magnetic pole outside the annular permanent magnet 32 is an N pole, which is not specifically limited, wherein the annular permanent magnet 32 may be an integrated structure, or may be formed by connecting a plurality of tile-shaped magnets arranged along the circumferential direction by a shaped material.

In addition, it should be noted that the linear motor shown in this embodiment further includes a first fixing member 13 and a second fixing member 14. In the case where a cylindrical air gap is formed between the inner stator 21 and the outer stator 22, the outer stator 22 may be fixedly installed between the first fixing member 13 and the second fixing member 14, an extension portion axially extending toward one side of the first fixing member 13 is provided on the second fixing member 14, and the inner stator 21 is fixedly installed on the extension portion. The first fixing piece 13 and the second fixing piece 14 are both hollow and cylindrical, the air cylinder 5 is coaxially mounted on the inner side of the second fixing piece 14, and the end portion of the leaf spring 4 is connected with one side face, far away from the second fixing piece 14, of the first fixing piece 13 so as to be connected with one end of the stator 2.

Example 2

As shown in fig. 3, the present embodiment is based on the improvement of embodiment 1, and also provides a linear compressor. Embodiment 2 differs from embodiment 1 in that only one movement 100 is provided in the housing 6.

In order to ensure the stability of the linear compressor during operation, the damping structure 10 is installed in the back pressure chamber 8, and one end of the damping structure 10 is connected to the middle of the flat spring 4 and the other end is connected to the housing 6. The damping structure 10 may be a spring, a spring plate, an elastic rod, etc. known in the art, and is not limited herein. Here, the vibration generated in the movement 100 when the piston 1 reciprocates in the cylinder 5 can be effectively cancelled by the buffering and vibration-damping action of the vibration-damping structure 10, and the vibration-damping action on the casing 6 of the linear compressor is realized.

Specifically, the damping structure 10 shown in the present embodiment includes a damping spring 110 and a damping block 111; the damping spring 110 is arranged coaxially with the piston 1; the damping block 111 is installed in the middle of the damping spring 110, one end of the damping spring 110 is connected to the middle of the flat spring 4, and the other end is connected to the housing 6.

Therefore, when the mover 3 shown in this embodiment cooperates with the piston 1 to perform reciprocating motion, a body (other components except the mover 3) of the linear compressor may generate a slight vibration due to resonance of the plate spring 4 and friction during the motion, and at this time, by providing the vibration damping block 111 and the vibration damping spring 110, a force opposite to the body of the linear compressor may be generated by the vibration of the vibration damping block 111, so as to counteract the vibration on the body of the linear compressor, thereby achieving a vibration damping effect on the body of the linear compressor.

Example 3

As shown in fig. 4 to 6, the present embodiment further provides a linear compressor based on the improvement of embodiment 1. Embodiment 3 differs from embodiment 1 in that, in the case where a cylindrical air gap is formed between the inner stator 21 and the outer stator 22, the cylindrical air gap is straight along the moving direction of the piston 1. The inner side surface of the corresponding iron core 221 of the outer stator 22 is provided with a plurality of protrusions arranged along the circumference, each protrusion is wound with an excitation winding 222, the mover 3 comprises two groups of coaxially connected annular permanent magnets 32, and the magnetic poles of the two groups of annular permanent magnets 32 are arranged along the radial direction of the linear compressor and are arranged in opposite directions.

Specifically, eight protrusions shown in the present embodiment may be specifically provided, accordingly, eight field coils arranged along the circumferential direction are wound on the outer stator 22, and the iron cores 221 of the inner stator 21 and the outer stator 22 are each formed by stacking a plurality of silicon steel sheets with corresponding shapes. Meanwhile, in this embodiment, the magnetic poles inside one group of the annular permanent magnets 32 on the mover 3 are specifically set to be N poles, and the magnetic poles outside the group of the annular permanent magnets 32 are specifically set to be S poles, and correspondingly, the magnetic poles inside the other group of the annular permanent magnets 32 are set to be S poles, and the magnetic poles outside the group of the annular permanent magnets are set to be N poles. In this way, when the magnetic field generated by the excitation winding 222 changes periodically, the mover 3 may be driven to reciprocate along the axial direction of the linear compressor with respect to the stator 2 based on the interaction of the magnetic field between the excitation winding 222 and the two sets of annular permanent magnets 32. Each group of the annular permanent magnets 32 may be an integral structure, or may be formed by connecting a plurality of tile-shaped magnets arranged along the circumferential direction by a molding material, which is not specifically limited herein.

It should be noted that, in this embodiment, a plurality of protrusions arranged along the circumference may also be provided on the outer side surface of the inner stator 21, each protrusion is wound with the excitation winding 222, and the mover 3 includes two sets of coaxially connected annular permanent magnets 32, and the magnetic poles of the two sets of annular permanent magnets 32 are arranged along the radial direction of the linear compressor and in opposite directions.

Example 4

As shown in fig. 7, the present embodiment is based on the improvement of embodiment 3, and also provides a linear compressor. Embodiment 4 is different from embodiment 3 in that, in order to further ensure the stability of the linear compressor during operation, a damping structure 10 is provided in each of the back pressure chambers 8 corresponding to the two opposed movements 100, and one end of the damping structure 10 is connected to the middle of the leaf spring 4 and the other end is connected to the housing 6.

The damping structure 10 shown in this embodiment includes a damping spring 110 and a damping block 111; the damping spring 110 is arranged coaxially with the piston 1; the damping block 111 is installed in the middle of the damping spring 110, one end of the damping spring 110 is connected to the middle of the flat spring 4, and the other end is connected to the housing 6.

Meanwhile, the embodiment further improves the structure of the linear motor, and the structure is specifically as follows:

in the case that a cylindrical air gap is formed between the inner stator 21 and the outer stator 22, the present embodiment further specifically provides that the inner stator 21 is connected to the iron core 221 at the end of the outer stator 22 away from the leaf spring 4, so that the end of the cylindrical air gap away from the leaf spring 4 is closed; the excitation windings 222 are circumferentially arranged on the inner stator 21 or the outer stator 22, the mover 3 includes two sets of coaxially connected annular permanent magnets 32, and the magnetic poles of the two sets of annular permanent magnets 32 are arranged along the radial direction of the linear compressor and are arranged in opposite directions.

Here, in this embodiment, the magnetic poles inside one group of the annular permanent magnets 32 on the mover 3 are N poles, the magnetic poles outside the group of the annular permanent magnets 32 are S poles, and correspondingly, the magnetic poles inside the other group of the annular permanent magnets 32 are S poles, and the magnetic poles outside the group of the annular permanent magnets are N poles. In this way, when the magnetic field generated by the excitation winding 222 changes periodically, the mover 3 may be driven to reciprocate along the axial direction of the linear compressor with respect to the stator 2 based on the interaction of the magnetic field between the excitation winding 222 and the two sets of annular permanent magnets 32.

In the embodiment, by optimizing the configuration of the iron core 221 structures of the inner stator 21 and the outer stator 22, only one air gap opening is provided for the magnetic circuit of the linear motor, so that the air gap reluctance of the magnetic circuit of the stator on the linear motor can be effectively reduced, the efficiency of the linear motor and the thrust to the mover 3 are improved, and the efficiency of the linear compressor can be effectively improved.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims (10)

1. A piston, comprising:

the piston comprises a piston body, wherein an air cavity is formed in the piston body;

the first end of the first air passage and the first end of the second air passage are both communicated with the air cavity, the second end of the first air passage is formed at one end of the piston body, and the second end of the second air passage is formed at the other end of the piston body;

the first air valve is arranged on the first air passage, and the second air valve is arranged on the second air passage;

the pneumatic shaft sleeve is sleeved on the side wall of the piston body, the air cavity is communicated with the inner side face of the pneumatic shaft sleeve, and a plurality of throttling air holes are formed in the side wall of the pneumatic shaft sleeve.

2. The piston of claim 1 wherein the chamber wall of the air chamber is configured with a vent hole, the vent hole is communicated with the inner side surface of the pneumatic sleeve, and the outer side surface of the pneumatic sleeve is flush with or higher than the side surface of the piston body.

3. The piston of claim 1 wherein said first air valve and said second air valve are each one-way valves, said first air valve for controlling the directional passage of air from said first air passage into said air chamber, said second air valve for controlling the directional passage of air from said second air passage into said air chamber.

4. The piston according to any one of claims 1 to 3, wherein the other end of the piston body is configured with a connecting seat;

and/or, the piston body comprises a first segment and a second segment; the first segment is coaxially connected with the second segment; the pneumatic shaft sleeve is coaxially sleeved on the side wall of at least one of the first section and the second section.

5. A linear compressor, including outer casing and inner works, the said inner works is placed in the cavity of the said outer casing, the said inner works include stator, runner, leaf spring and air cylinder, the said stator, said runner and said air cylinder are set up coaxially, the said stator and said runner form the linear motor, characterized by, also include the piston as stated in any claim 1 to 4;

the piston is slidably arranged in the cylinder, a compression cavity is formed between one end of the piston and the wall surface of the first side of the shell, a back pressure cavity is formed between the other end of the piston and the wall surface of the second side of the shell, an exhaust channel is arranged on the shell, and the exhaust channel is communicated with the compression cavity;

the other end of the piston and one end of the rotor are both connected with the middle of the leaf spring, and the end part of the leaf spring is connected with one end of the stator.

6. The linear compressor of claim 5, wherein a damping structure is installed in the back pressure chamber, and one end of the damping structure is connected to a middle portion of the leaf spring and the other end thereof is connected to the housing.

7. The linear compressor of claim 6, wherein the damping structure includes a damping spring and a damping block; the damping spring is coaxially arranged with the piston; the damping block is arranged in the middle of the damping spring, one end of the damping spring is connected with the middle of the leaf spring, and the other end of the damping spring is connected with the shell.

8. A linear compressor as claimed in any one of claims 5 to 7 wherein one said core is disposed within said housing; or two machine cores are arranged in the shell, are arranged along the axial direction of the piston and are arranged oppositely, and compression cavities on the two machine cores are communicated with the exhaust channel;

an anti-collision device is arranged between one end of the cylinder, which is far away from the leaf spring, and the shell, a ventilation channel is constructed on the anti-collision device, and the compression cavity is communicated with the exhaust channel through the ventilation channel.

9. The linear compressor of any one of claims 5 to 7, wherein the stator includes an inner stator and an outer stator, the inner stator and the outer stator being coaxially arranged, one of the inner stator and the outer stator being an iron core, the other of the inner stator and the outer stator including an iron core and an excitation winding;

the rotor comprises a rotor framework and an annular permanent magnet; the annular permanent magnet is arranged on the rotor framework; one end of the rotor framework is connected with the middle part of the leaf spring and the connecting seat on the piston body respectively;

the inner stator is coaxially arranged on the inner side of the annular permanent magnet, and the outer stator is coaxially arranged on the outer side of the annular permanent magnet; the inner stator and the outer stator form a cylindrical air gap, the annular permanent magnet is coaxially arranged in the cylindrical air gap, or one of the inner stator and the outer stator which is an iron core is connected with the annular permanent magnet.

10. Linear compressor according to claim 9,

when a cylindrical air gap is formed between the inner stator and the outer stator, the cylindrical air gap is straight along the moving direction of the piston; the excitation windings are circumferentially arranged on the inner stator or the outer stator, the rotor comprises a group of annular permanent magnets, and magnetic poles of the annular permanent magnets are arranged along the radial direction of the linear compressor; or, the outer side surface of the inner stator or the inner side surface of the outer stator is provided with a plurality of protrusions which are arranged along the circumference, each protrusion is wound with the excitation winding, the rotor comprises two groups of coaxially connected annular permanent magnets, and the magnetic poles of the two groups of annular permanent magnets are arranged along the radial direction of the linear compressor and are opposite in arrangement direction;

or, in the case that a cylindrical air gap is formed between the inner stator and the outer stator, the inner stator is connected with the iron core at one end of the outer stator far away from the leaf spring, so that one end of the cylindrical air gap far away from the leaf spring is closed; the rotor comprises two groups of coaxially connected annular permanent magnets, and the magnetic poles of the two groups of annular permanent magnets are arranged along the radial direction of the linear compressor and are arranged in opposite directions.

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