CN112901442B - DC linear compressor - Google Patents

Abstract

The present application relates to a direct current linear compressor, comprising a mover having a piston and a stator having a cylinder, the mover being configured to reciprocate relative to the stator, the cylinder being provided with a direct current permanent magnet; the piston is provided with a direct current coil and is configured to reciprocate relative to the cylinder under the driving of the rotor; the direct current coil interacts with the direct current permanent magnet under the state of introducing direct current so as to enable the piston to suspend. When the rotor reciprocates relative to the stator, the direct-current linear compressor can drive the piston to reciprocate relative to the cylinder; because the cylinder is provided with the direct current permanent magnet, the piston is provided with the direct current coil, when the compressor is started, direct current is introduced into the direct current coil, a magnetic field generated by the direct current coil interacts with a magnetic field of the direct current permanent magnet, the piston can be suspended, and dry friction between the piston and the cylinder is avoided.

Description

DC Linear Compressor

technical field

The present application relates to the technical field of compressors, for example, it relates to a DC linear compressor.

Background technique

At present, an oil pump is installed at the bottom of the compressor, through which the piston is provided with lubricating oil to reduce frequent friction between the piston and the cylinder. However, the oil pump limits the installation height of the linear compressor. In order to further reduce the height of the linear compressor, an oil-free linear compressor is designed to support the suspension of the piston through the compressed gas leakage at the exhaust end, which saves the installation of the oil pump and solves the problem. The problem of heat transfer efficiency drop caused by oil entering the refrigeration system is solved. However, oil-free compressors cannot carry out dry friction for a long time. The existing technical solutions can only carry out special treatment on the contact surface of the piston or cylinder, such as DlC spraying, etc., and the use of high wear-resistant materials has brought about increased costs and difficult processes. improvement.

In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art: in the early stage of operation of the oil-free linear compressor, when the exhaust pressure is not formed, the piston cannot be suspended by the leaked compressed air, and there will be a gap between the piston and the cylinder. Dry friction occurs, and frequent dry friction operation will lead to rough friction surface, which will lead to wear and damage to the compressor.

SUMMARY OF THE INVENTION

In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is presented below. The summary is not intended to be an extensive overview nor to identify key/important elements or to delineate the scope of these embodiments, but rather serves as a prelude to the detailed description that follows.

An embodiment of the present disclosure provides a DC linear compressor to solve the technical problem of dry friction between the piston and the cylinder at the initial stage of operation of the linear compressor.

In some embodiments, the DC linear compressor includes a mover with a piston and a stator with a cylinder, the mover is configured to reciprocate relative to the stator, the cylinder is provided with a DC permanent magnet; the piston is provided with a DC coil, configured to Driven by the mover, it reciprocates relative to the cylinder; among them, the DC coil interacts with the DC permanent magnet under the state of direct current, so that the piston is suspended.

The DC linear compressor provided by the embodiments of the present disclosure can achieve the following technical effects: when the mover reciprocates relative to the stator, it can drive the piston to reciprocate relative to the cylinder; since the cylinder is provided with a DC permanent magnet and the piston is provided with a DC coil, When the compressor is started, direct current is fed into the DC coil, so that the magnetic field generated by the DC coil interacts with the magnetic field of the DC permanent magnet, thereby enabling the piston to levitate and avoiding dry friction between the piston and the cylinder.

The foregoing general description and the following description are exemplary and explanatory only and are not intended to limit the application.

Description of drawings

One or more embodiments are exemplified by the corresponding drawings, and these exemplifications and drawings do not constitute a limitation to the embodiments, and elements with the same reference numerals in the drawings are shown as similar elements, The drawings are not limited to scale and in which:

Fig. 1 is a schematic structural diagram of a DC linear compressor provided by an embodiment of the present disclosure;

Fig. 2 is an enlarged view of part A of Fig. 1;

Fig. 3 is an axial view of the positional relationship between the DC coil and the DC permanent magnet provided by another disclosed embodiment.

Reference number:

1. Mover; 10. Mover permanent magnet; 2. Piston; 20. DC coil; 3. Stator; 4. Cylinder; 40. DC permanent magnet; 41. Stator coil; 5. Resonant spring; 6. Exhaust valve piece.

Detailed ways

In order to understand the characteristics and technical content of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings. The attached drawings are only for reference and description, and are not intended to limit the embodiments of the present disclosure. In the following technical description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may be practiced without these details. In other instances, well-known structures and devices may be shown simplified in order to simplify the drawings.

Fig. 1 is a schematic structural diagram of a DC linear compressor provided by an embodiment of the present disclosure. Fig. 2 is an enlarged view of part A of Fig. 1 . As shown in Figures 1 and 2, the embodiment of the present disclosure provides a DC linear compressor, including a mover 1 with a piston 2 and a stator 3 with a cylinder 4, the mover 1 is configured to reciprocate relative to the stator 3, The cylinder 4 is provided with a DC permanent magnet 40; the piston 2 is provided with a DC coil 20, which is configured to reciprocate relative to the cylinder 4 under the drive of the mover 1; wherein, the DC coil 20 is connected to the DC permanent magnet 40 under the state of direct current. Interact to levitate piston 2.

Generally, the stator 3 of a linear compressor is provided with a stator coil 41, and the mover 1 is provided with a mover permanent magnet 10. When power is supplied to the stator coil 41 of the compressor, an alternating electric field will be generated in the stator coil 41. The principle is that an alternating magnetic field will be formed, and the alternating magnetic field will interact with the mover permanent magnet 10, so that the mover 1 connected to the mover permanent magnet 10 reciprocates relative to the stator 3, and also drives the mover 1 connected to the mover 1. The piston 2 reciprocates in the cylinder 4, and the resonant spring 5 connected with the mover 1 performs simple harmonic motion. During the reciprocating operation of the piston 2, the suction valve plate and the exhaust valve plate 6 of the compressor will open and close relatively to form a compression process; most of the compressed gas is discharged outside the compressor through the exhaust chamber, and a small part Discharge into the gap between the cylinder 4 and the piston 2 along the high-pressure gas leakage hole to form high-pressure gas, which generates a radial force on the piston 2, thereby using the high-pressure gas to levitate the piston 2. When the compressor is powered on for the first time, since the compressed gas has not yet been formed, the piston 2 cannot be suspended by the leaked compressed air, and there will be dry friction between the piston 2 and the cylinder 4 .

Therefore, a DC permanent magnet 40 is set on the cylinder 4, and a DC coil 20 is set on the piston 2. When the DC linear compressor is powered on for the first time, the DC coil 20 of the piston 2 is energized first, and the DC coil 20 generates an electromagnetic field, and the electromagnetic field generated by the DC coil 20 It interacts with the electromagnetic field of the DC permanent magnet 40 to make the piston 2 suspend, thereby preventing dry friction between the piston 2 and the cylinder 4 . The electromagnetic field produced by the DC coil 20 and the electromagnetic field of the DC permanent magnet 40 may attract or repel each other. The DC coil 20 and the DC permanent magnet 40 form a suspension mechanism, and the suspension mechanism is arranged symmetrically along the axis of the piston 2. Like this, the piston 2 and the cylinder Regardless of whether the active forces between 4 attract or repel each other, the active force received by the piston 2 is symmetrical, so that the piston 2 can maintain suspension.

The DC coil 20 is set on the piston 2, the stator coil 41 is set on the stator 3, and the piston 2 is set on the mover 1. When the compressor is not running, the stator coil 41 is not electrified and does not generate a magnetic field. The DC coil 20 and the stator coil 41 There is a certain distance between them. When the two coils start to be energized, the two generate a magnetic field instantaneously. Since there is a certain distance between the DC coil 20 and the stator coil 41, the mutual influence of the magnetic fields of the two is small. Moreover, the DC coil 20 is energized when the compressor is started, and interacts with the DC permanent magnet 40 to cause the piston 2 to move relative to the cylinder 4 for the first time in a suspended state. After the compressed gas is generated in the cylinder 4, the DC coil 20 can be disconnected. Electricity no longer relies on magnetic levitation, but relies on the compressed gas discharged to the gap between the cylinder 4 and the piston 2 along the high-pressure gas leakage hole to levitate the piston 2. In this way, the DC coil The magnetic field generated by 20 affects the magnetic field of the stator coil 41 , thereby affecting the stability of the reciprocating motion between the mover 1 and the stator 3 . In addition, the DC coil 20 can be controlled by direct current. After the compressor is started, the DC coil 20 is energized to make the piston 2 float and close to the cylinder 4 to compress the gas, and then the DC coil 20 is disconnected.

In some embodiments, the DC permanent magnet 40 is disposed on the inner wall of the cylinder 4 . The piston 2 extends to the inside of the cylinder 4, and reciprocates relative to the cylinder 4. The DC permanent magnet 40 is arranged on the inner wall of the cylinder 4, so that the distance between the piston 2 and the piston 2 is closer, and the effect on the piston 2 is more obvious. Optionally, the inner wall of the cylinder 4 is provided with a groove, and the DC permanent magnet 40 is embedded in the groove. In this way, the DC permanent magnet 40 can be firmly installed on the cylinder 4 . Optionally, the thickness of the DC permanent magnet 40 is less than or equal to the depth of the groove. In this way, the surface of the DC permanent magnet 40 faces the piston 2 , and the DC permanent magnet 40 does not extend out of the groove, so as to avoid blocking the reciprocating movement of the piston 2 .

In some embodiments, the DC permanent magnet 40 is arranged along the circumference of the cylinder 4 , or arranged symmetrically with respect to the axis of the cylinder 4 .

The DC permanent magnet 40 is arranged along the circumference of the cylinder 4 , that is, the DC permanent magnet 40 extends along the inner circumference of the cylinder 4 in a ring shape. In this way, the magnetic field generated by the DC permanent magnet 40 is symmetrical, and with the corresponding position of the DC coil 20, a balanced force is generated on the piston 2 to keep the piston 2 suspended, avoiding contact with the inner wall of the cylinder 4 and causing dry friction. The DC permanent magnet 40 is symmetrically arranged relative to the axis of the cylinder 4. For example, the DC permanent magnet 40 includes two sub-magnets, and the two sub-magnets are symmetrical to the axis of the cylinder 4, so that a symmetrical magnetic field can be produced, and the corresponding position of the DC coil 20 is set. , to produce a balanced force on the piston 2 to keep the piston 2 in suspension.

In some embodiments, as shown in FIG. 1 , the stator 3 further has a stator coil 41 , and the DC permanent magnet 40 is arranged corresponding to the front and/or rear of the stator coil 41 .

"Front" refers to the side of the compressor close to the discharge valve plate 6, and "rear" refers to the side of the compressor close to the resonant spring 5. The stator 3 includes a base body, the base body is provided with a stator 3 slot for accommodating the stator coil 41, the front of the stator coil 41 refers to a part of the base body located in front of the stator coil 41, and the rear of the stator coil 41 refers to a part of the base body located behind the stator coil 41. The DC permanent magnet 40 corresponds to the front and/or rear of the stator coil 41 , and is arranged on the base body of the DC permanent magnet 40 corresponding to the front and/or rear of the stator coil 41 of the cylinder 4 . The reciprocating motion between the stator 3 and the mover 1 of the compressor itself is realized by using the principle of electromagnetic induction through the interaction of the alternating magnetic field formed by the stator coil 41 and the mover permanent magnet 10. When the cylinder 4 is provided with a DC permanent magnet When the magnet 40, because the DC permanent magnet 40 itself has certain magnetism, it is possible to have an impact on the magnetic field of the stator coil 41, therefore, the front and/or rear of the DC permanent magnet 40 corresponding to the stator coil 41 is arranged, so that the DC permanent magnet 40 and the position of the stator coil 41 are staggered, so as to avoid the influence of the magnetic field of the DC permanent magnet 40 itself on the magnetic field generated by the stator coil 41 .

Optionally, the thickness of the DC permanent magnet 40 is 1.5mm˜2.5mm. This because the wall thickness of cylinder 4 is generally between 3mm～5mm, the thickness of dc permanent magnet 40 is not easy to be too thick, avoids to have an impact on the mechanical strength of cylinder 4 wall, when in this range, dc permanent magnet 40 can be connected with dc coil 20 Interact to levitate piston 2.

In some embodiments, the DC coil 20 is disposed on the outer wall of the piston 2 . The DC coil 20 is on the outer wall of the piston 2, and the outside of the outer wall of the piston 2 is the inner wall of the cylinder 4, so that the DC coil 20 is closer to the DC permanent magnet 40 of the cylinder 4, and the DC coil 20 and the DC permanent magnet 40 can be lifted. effect between them. Optionally, the outer wall of the piston 2 is provided with a slot, and the DC coil 20 is embedded in the slot. In this way, the DC coil 20 can be firmly attached to the piston 2 .

In some embodiments, the DC coil 20 is arranged along the circumference of the piston 2 , or arranged symmetrically with respect to the axis of the piston 2 . The DC coil 20 is arranged along the circumference of the piston 2 , that is, the DC coil 20 extends along the outer circumference of the piston 2 in a ring shape. In this way, the magnetic field generated by the DC coil 20 is symmetrical, and with the corresponding position of the DC permanent magnet 40, a balanced force can be generated on the piston 2 to keep the piston 2 suspended and avoid contact with the inner wall of the cylinder 4 and cause dry friction. The positional relationship between the DC coil 20 and the DC permanent magnet 40 is shown in Figure 3. The DC coil 20 is arranged symmetrically with respect to the axis of the piston 2. In this way, the DC coil 20 produces a symmetrical magnetic field when the current is applied, and the DC permanent magnet 40 corresponds to The position is set so that the piston 2 is subjected to symmetrical repulsion or attraction, so that the force is balanced to achieve suspension.

In some embodiments, there are multiple DC permanent magnets 40 arranged at intervals along the axial direction of the cylinder 4 . The cylinder 4 is provided with a plurality of DC permanent magnets 40, and the piston 2 is correspondingly provided with the same number of DC coils 20. In this way, the piston 2 interacts with the cylinder 4 in multiple areas in the axial direction, so that the movement of the piston 2 is more stable, and avoiding the The area is too small, causing piston 2 to be out of balance and collide with cylinder 4. Optionally, the number of DC permanent magnets 40 is two, the number of DC coils 20 is two groups, and the distance between two DC permanent magnets 40 is the same as the distance between two groups of DC coils 20 . In this way, the magnetic force received by the piston 2 is balanced.

In some embodiments, the distance from the outer sides of the farthest DC permanent magnets 40 is less than or equal to the axial length of the stator 3 . In this way, after the compressor starts, the piston 2 moves toward the exhaust end for the first time, and when the positions of the DC coil 20 and the DC permanent magnet 40 are opposite, the piston 2 stops moving, so as to prevent the piston 2 from continuing to move toward the exhaust end and hitting the exhaust valve. slice 6. If the distance from the outer side of the farthest DC permanent magnet 40 is greater than the axial length of the stator 3, for example, the position of the DC permanent magnet 40 at the rear of the cylinder 4 remains unchanged, and the DC permanent magnet 40 at the front of the cylinder 4 is in the same position. The position on the cylinder 4 exceeds the area covered by the stator 3, and the DC permanent magnet 40 is closer to the exhaust valve plate 6. When the piston 2 moves to the exhaust end, it needs to move to a position closer to the exhaust end to make the DC coil 20 and The positions of the DC permanent magnets 40 correspond to each other, so that the piston 2 easily hits the exhaust valve plate 6 . Therefore, by limiting the distance between the outer sides of the farthest DC permanent magnets 40 to be less than or equal to the axial length of the stator 3, the piston 2 is prevented from colliding with the exhaust valve plate 6 and causing damage.

In some embodiments, there are multiple sets of DC coils 20 . The number of DC coils 20 can also be set in multiple groups, so that the piston 2 can interact with the cylinder in multiple areas in the axial direction, so that the movement of the piston 2 can be more stable, and avoid collisions between the piston 2 and the cylinder due to the small suspension area. .

In some embodiments, the spacing between the multiple sets of DC coils 20 is the same as the spacing between the multiple DC permanent magnets 40 . In this way, when the piston 2 moves close to the exhaust end and stops, the positions of the DC coil 20 and the DC permanent magnet 40 can correspond, and the levitation state of the piston 2 is more stable.

The above description and drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may incorporate structural and other changes. The examples merely represent possible variations. Individual components and functions are optional unless explicitly required, and the order of operations may vary. Portions and features of some embodiments may be included in or substituted for those of other embodiments. The scope of embodiments of the present disclosure includes the full scope of the claims, and all available equivalents of the claims. When used in the present application, although the terms 'first', 'second', etc. may be used in the present application to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without changing the meaning of the description, a first element could be called a second element, and likewise, a second element could be called a first element, as long as all occurrences of "first element" are renamed consistently and all occurrences of "Second component" can be renamed consistently. The first element and the second element are both elements, but may not be the same element. Also, the terms used in the present application are used to describe the embodiments only and are not used to limit the claims. As used in the examples and description of the claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well unless the context clearly indicates otherwise . Similarly, the term "and/or" as used in this application is meant to include any and all possible combinations of one or more of the associated listed ones. In addition, when used in this application, the term "comprise" and its variants "comprises" and/or comprising (comprising) etc. refer to the presence of stated features, integers and/or components, but do not exclude The presence or addition of one or more other features, integers, components and/or groupings of these. Without further limitations, an element defined by the statement "comprising a ..." does not exclude the presence of additional identical elements in the process, method or apparatus comprising said element. Herein, what each embodiment focuses on may be the difference from other embodiments, and the same and similar parts of the various embodiments may refer to each other. For the method, product, etc. disclosed in the embodiment, if it corresponds to the method part disclosed in the embodiment, then the relevant part can refer to the description of the method part.

The orientations or positional relationships indicated by the terms "front", "rear", "inner" and "outer" herein are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing this text and simplifying the description, rather than Nothing indicating or implying that a referenced device or element must have a particular orientation, be constructed, and operate in a particular orientation should therefore not be construed as limiting the invention. In the description herein, unless otherwise stipulated and limited, the terms "installation", "connection" and "connection" should be interpreted in a broad sense, for example, it can be a mechanical connection or an electrical connection, and it can also be the internal communication of two components, It may be directly connected or indirectly connected through an intermediary, and those skilled in the art can understand the specific meanings of the above terms according to specific situations. Herein, unless otherwise stated, the term "plurality" means two or more. In this document, the term "and/or" is an associative relationship describing objects, which means that there may be three relationships. For example, A and/or B means: A or B, or, A and B, these three relationships.

Claims (10)

1. A DC linear compressor, comprising a mover with a piston and a stator with a cylinder, the mover is configured to reciprocate relative to the stator, it is characterized in that the cylinder is provided with a DC permanent magnet; The piston is provided with a DC coil, which is configured to reciprocate relative to the cylinder under the drive of the mover; wherein, the DC coil interacts with the DC permanent magnet in the state of being fed with DC, so that the The piston is suspended; the DC coil is configured to be energized when the DC linear compressor is started, and the power is cut off after the compressed gas is generated in the cylinder; the number of the DC permanent magnets is multiple, and along the The cylinders are arranged at intervals in the axial direction; the distance from the outer sides of the DC permanent magnets farthest away is less than or equal to the axial length of the stator. 2. The DC linear compressor according to claim 1, wherein the DC permanent magnet is arranged on the inner wall of the cylinder. 3. The DC linear compressor according to claim 1, wherein the DC permanent magnet is arranged along the circumferential direction of the cylinder. 4. The DC linear compressor according to claim 3, wherein the DC permanent magnet is arranged symmetrically with respect to the axis of the cylinder. 5 . The DC linear compressor according to claim 1 , wherein the stator further has a stator coil, and the DC permanent magnet is arranged corresponding to the front and/or rear of the stator coil. 6. The DC linear compressor according to claim 1, wherein the DC coil is arranged on the outer wall of the piston. 7. The DC linear compressor according to claim 1, wherein the DC coil is arranged along the circumference of the piston. 8. The DC linear compressor according to claim 7, wherein the DC coil is arranged symmetrically with respect to the axis of the piston. 9. The DC linear compressor according to claim 1, characterized in that there are multiple sets of the DC coils. 10. The DC linear compressor according to claim 9, characterized in that the distance between the multiple sets of DC coils is the same as the distance between the multiple DC permanent magnets.

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