JP4273738B2 - Linear compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a linear compressor mainly using a linear motor and a linear motor used for a refrigeration cycle or the like.
[0002]
[Prior art]
  In recent years, the need for higher efficiency of refrigeration equipment has further increased, and a compressor using a linear motor is being put to practical use because it can achieve a significant reduction in sliding loss because of its simple mechanical structure.
[0003]
  Patent Documents that describe the structure of a linear compressor equipped with a conventional linear motor are described (for example, see Patent Document 1).
[0004]
  The conventional linear motor and linear compressor will be described below with reference to the drawings.
[0005]
  12 is a cross-sectional view of a linear compressor equipped with a conventional linear motor, and FIG. 13 is an enlarged view of a main part of FIG.
[0006]
  In FIG. 12, the compression mechanism section 7 is composed of a linear motor 8, a cylinder 9, a piston 10, an elastic element 11, and a cylinder head 12 c, and is elastically supported in a sealed casing 14 by a suspension spring 13.
[0007]
  The linear motor 8 has a hollow cylindrical stator (second silicon steel plate layer) 8a having a winding 8e on the outer peripheral surface side of a stator (first silicon steel plate layer) 8b formed in a hollow cylindrical shape. A hollow cylindrical non-magnetic magnet shell 4 is formed between the first silicon steel plate layer 8b and the second silicon steel plate layer 8a, and the outside of the magnet shell 4 is supported. A plurality of magnets 8c are bonded to the groove portions on the surface to constitute the mover 8d. The mover 8d is connected to the piston 10, and the piston 10 is inserted into the cylinder 9 so as to reciprocate. The cylinder 9, the piston 10, the stator 8 a, and the stator 8 b share an axis, and the piston 10 holds the mover 8 d by a bearing portion 10 a formed between the cylinder 9 and the magnet 10. 8c keeps a predetermined gap between the stator 8a and the stator 8b.
[0008]
  In order to obtain practical efficiency, the magnet 8c normally uses a magnet material made of a rare earth having a strong magnetic field and is magnetized in a direction perpendicular to the reciprocating direction.
[0009]
  The movable element 15 is composed of the piston 10, the movable element 8d of the linear motor 8, and the fixed element 16 is composed of the cylinder 9, the stators 8a and 8b of the linear motor 8, and the like.
[0010]
  In the elastic element 11, the inner peripheral part 11 a of the elastic element 11 is fixed to the movable element 15, and the outer peripheral part 11 b is fixed to the fixed element 16. The elastic body 11 is a plate-like spring.
[0011]
  The lubricating oil 17 filled in the sealed casing 14 is supplied to the sliding portion by an oil supply device (not shown).
[0012]
  The operation of the linear motor and the linear compressor configured as described above will be described below.
[0013]
  First, the operation of the linear motor 8 will be described.
[0014]
  When the winding 8e is energized through current, the stator 8b (first silicon steel plate layer) through the gap, the magnet 8c, the gap, the stator 8a (second silicon steel plate layer), the gap, the magnet 8c, the gap, the stator 8b (first A series of magnetic flux loops to one silicon steel layer to form a magnetic circuit. The magnet 8c is attracted to the magnetic poles formed on the stator 8a (second silicon steel plate layer) by this magnetic flux. Next, by alternating current to the winding 8e, the mover 8d operates while reciprocating in the left-right direction in FIG. 12 between the stator 8a and the stator 8b.
[0015]
  Next, the mechanism of the linear compressor will be described. When an alternating current is applied to the linear motor 8, as described in the previous operation of the linear motor, a reciprocating force in the axial direction is generated in the mover 8d of the linear motor 8. With this force, the piston 10 connected to the mover 8d deforms the elastic element 11 and repeats reciprocating motion in the axial direction. At this time, the repulsive force of the elastic element 11 is used, and the resonance action is used by operating at an operation frequency that matches the resonance frequency determined by the mass of the movable element 15 and the fixed element 16 and the spring constant of the elastic element 11. And efficient operation becomes possible.
[0016]
  Refrigerant gas from a cooling system (not shown) is guided into the cylinder head 12c through a suction pipe (not shown) and a suction muffler 19a and reaches the compression chamber 20 in the cylinder 9. The refrigerant gas that reaches the compression chamber 20 is compressed by the reciprocating motion of the piston 10 described above. The compressed refrigerant gas is once discharged into the cylinder head 12c and then discharged to the cooling system via the discharge muffler 19b and a discharge pipe (not shown).
[0017]
  The refrigerant used is mainly CFC-12 or HCFC-22 which has been used for a long time in the cooling system, and recently HFC-134a, R600a, R410A, etc., and the lubricating oil 17 is mainly compatible with the refrigerant. Some are used.
[0018]
[Patent Document 1]
      Japanese Patent No. 2912024
[0019]
[Problems to be solved by the invention]
  However, in the above configuration, since the mover 8d swings between the stator 8b (first silicon steel plate layer) and the stator 8a (second silicon steel plate layer), the mover 8d is fixed to the stator 8b (first silicon steel layer). Air gaps are formed respectively for the steel plate layer) and the stator 8a (second silicon steel plate layer). And the loop of the magnetic flux which drives the needle | mover 8d which generate | occur | produced in stator 8a, 8b straddles two space | gap.
[0020]
  These two gaps are provided with a necessary distance to prevent the movable element 8d from coming into contact with both of the stators 8a and 8b, but the space becomes a magnetic resistance and is proportional to the square of the distance. Since the magnetic flux is reduced, in order to obtain the thrust required to drive the mover 8d, the current supplied to the winding 8e is increased by an amount corresponding to the reduction of the magnetic flux due to the two gaps. Because it increases, it is difficult to increase efficiency.
[0021]
  At the same time, in order to obtain the thrust necessary to drive the mover 8d, the conventional linear motor 8 needs to increase the magnet 8c. However, since the magnet 8c generally uses an expensive rare earth as a material, the cost of the magnet 8c has increased significantly due to an increase in the size of the magnet 8c.
[0022]
  Furthermore, it is desirable that the two gaps formed between the mover 8d and the stators 8a and 8b have the same distance at any location. If there is a difference in distance, an unbalance of the magnetic attraction force occurs between them, and as a result, a twisting force in a direction perpendicular to the swinging direction of the mover 8d is generated, and sliding occurs in the support mechanism of the bearing portion 10a. This is because it not only causes loss, but also causes abnormal wear and shortens the service life.
[0023]
  In order to avoid this, if the distance between the two gaps is increased, the input increases and the magnet 8c needs to be further increased. Therefore, normally, the processing accuracy of the drive system including the magnet shell 4 is increased, but in order to increase the processing accuracy, it is necessary to increase the rigidity of the magnet shell 4 which is a movable part, and this is increased. The weight of the drive train increases. As a result, the thrust required to drive the mover 8d increases, the current supplied to the winding 8e increases, and the input increases.
[0024]
  Further, increasing the machining accuracy of the drive system is accompanied by an increase in cost in the manufacturing process.
[0025]
  Further, in the configuration of the conventional linear compressor equipped with the conventional linear motor 8, the magnet 8c and the stator 8a, and the magnetic attraction force imbalance between the magnet 8c and the stator 8b are movable as described above. A twisting force in a direction perpendicular to the reciprocating direction of the child 8d is generated, and in addition, gravity acts on the movable element 15 including the movable member 8d.
[0026]
  These squeezing forces are applied to the sliding portions of the piston 10 and the cylinder 9 functioning as bearings. However, as the magnetic attraction force increases, the sliding loss due to squeezing increases, the efficiency decreases, and the magnetic attraction force becomes extremely low. If it is large, wear of the sliding part may occur.
[0027]
  To compensate for these drawbacks, increasing the sliding length and reducing the surface pressure of the sliding part increases the size of the compressor.If the amount of magnet is reduced, the motor efficiency decreases and the motor thrust decreases. A deficiency such as shortage will occur. In addition, increasing the machining accuracy and assembly accuracy of the motor core and magnet accompanies an increase in cost.
[0028]
  Further, in the configuration of the conventional linear compressor equipped with the conventional linear motor, the compressor body vibrates greatly by the reciprocating movement of the movable element 15 using the resonance action, and this vibration is sealed through the suspension spring 13 and the sealed casing. 14 has a drawback that the vibration and noise of the sealed casing 14 are large.
[0029]
  In particular, in the conventional example, since the movable element 15 of the linear motor 8 has a horizontal arrangement in which the movable element 15 reciprocates in the horizontal direction, it is difficult to reduce vibration. This is because even if the suspension spring 13 that suspends the compression mechanism portion 7 is arranged in the horizontal direction, it is difficult to arrange the suspension spring 13 in the horizontal direction because the weight of the compression mechanism portion 7 is heavy. Therefore, the suspension spring 13 is often arranged in the vertical direction. In this case, the vibration direction of the compression mechanism unit 7 and the expansion / contraction direction of the suspension spring 13 are shifted by 90 degrees. That is, the suspension spring 13 must absorb the vibration transmission of the compression mechanism portion 7 not only by the spring constant in the expansion / contraction direction but also by a composite of the lateral spring constant shifted by 90 degrees from the expansion / contraction direction. It was difficult to sufficiently reduce vibration.
[0030]
  Even if not enough, if the rigidity of the suspension spring 13 is reduced to reduce the vibration transmission from the compression mechanism 7 to the sealed casing 14, the suspension spring 13 becomes longer and the air is sealed. The size of the casing 14 becomes large.
[0031]
  The present invention solves the above-described conventional problems, and an object thereof is to provide a low-cost and high-efficiency linear motor that reduces loss in a support mechanism for a mover.
[0032]
  It is another object of the present invention to provide a linear motor and a linear compressor that reduce sliding loss at a sliding portion and reduce vibration, and are small, low cost, low vibration, and highly efficient.
[0033]
[Means for Solving the Problems]
  According to a first aspect of the present invention, there is provided a stator having at least two magnetic poles and comprising a fixed iron core and a magnet wire engaged with the fixed iron core, and a movable iron core and a magnet positioned inside the stator. And a flexure bearing that supports the mover in a swinging direction by a plurality of arms formed on a substantially plate-like elastic material, and formed on the inner side of the stator. And the outer peripheral surface of the mover has a substantially cylindrical shape sharing the axis of the swinging direction of the mover, and one end is locked to the mover or a movable shaft formed to extend from the axis of the mover. The other end includes a coil spring that is locked to a spring holder fixed to the stator, and the flexure bearing supports the force that the mover is attracted to the stator by the magnetic attraction force. Radial stiffness that ensures a constant clearance over the entire circumference It has, is operated at a resonant frequency determined by the relationship between the spring constant and the stator and the mover of the mass of the sum of the coil spring having a larger spring constant than the flexure bearings and flexure bearingsWith linear motorBy integrating the magnet and the movable iron core, the air gap contained in the magnetic flux loop can be reduced, and the magnetic resistance can be reduced, so that the necessary magnetic force can be generated with a small and small magnet. It has the effect of reducing the loss in the supporting mechanism that supports the bending force and gravity in the direction perpendicular to the reciprocating direction of the child.
[0034]
  In addition, even when the mover rotates, the gap between the stator and the stator is maintained at a constant interval, preventing damage due to collision between the mover and the stator, and wear of support mechanisms such as bearings due to increased lateral force. In addition, it has an effect that it is easy to ensure assemblability and processing accuracy.
[0035]
  And a coil spring that has one end locked to the movable element or a movable shaft extending to the axis of the movable element, and the other end locked to a spring holder fixed to the stator. Yes, by driving near the resonance frequency that is created by the spring constant of the coil spring larger than that of the flexure bearing and the mass of the stator and mover, the resonance action at a relatively high resonance frequency can be used to increase the power with less input. The output (large amplitude of the mover) can be obtained.
[0036]
  further,A cylinder that shares an axis with the mover; and a piston that is reciprocally inserted into the cylinder and coupled to the mover. The reciprocating motion can be efficiently performed and the sliding loss due to the reduction of the side pressure between the cylinder and the piston can be reduced.
[0037]
  further,The piston andAboveThe mover is connected through a retractable rod made of an elastic body so that the axis of the piston and cylinder can be aligned even when the axis of the mover and cylinder are misaligned or the shaft is tilted. The retractable rod can be bent to absorb the shaft misalignment and the shaft inclination, and has the effect of reducing the sliding loss due to the reduction of the side pressure between the cylinder and the piston.
[0038]
  Claim 2The invention described inClaim 1In the invention described in (1), since the oil-free configuration does not use the lubricating oil, the amount of the refrigerant used in the cooling system can be reduced as much as the refrigerant does not dissolve in the lubricating oil.
[0039]
  Claim 3The invention described inClaim 1 or 2In this invention, the sliding portion between the cylinder and the piston is constituted by a gas bearing, so that the sliding portion becomes non-contact, so that the sliding loss can be reduced to almost zero and the sliding portion is worn. Have the effect of almost no.
[0040]
  Claim 4The invention described inClaim 2In the invention described in the above, since the self-lubricating material is used for at least one of the cylinder or the piston, the sliding part wear can be prevented without using lubricating oil due to the self-lubricating effect. Have
[0041]
  Claim 5The invention described inClaim 2In the invention described in the above, since the ceramic material is used for at least one of the cylinder or the piston, the wear resistance of the ceramic material can prevent the sliding portion from being worn without using lubricating oil. Have
[0042]
  The invention described in claim 6Claims 1 to 5In the invention according to any one of the above, since at least a part of the cylinder is inserted and arranged in the coil spring, the hermetic casing can be reduced in size, particularly in the swing direction.
[0043]
  Claim 7The invention described inClaims 1 to 6In the invention according to any one of the above, since the swinging direction of the mover coincides with the direction of gravity, gravity does not act in the radial direction of the mover, so the required rigidity in the radial direction of the flexure bearing is reduced. The hysteresis loss can be lowered accordingly.
[0044]
  Claim 8The invention described inClaim 7In the invention described in the above, since the dynamic vibration absorber made up of a spring that is elastically deformable in the swinging direction of the mover and a weight attached to the spring is attached to the sealed casing, Thus, the weight of the dynamic vibration absorber also has the effect of canceling the vibration of the sealed casing by swinging in the same gravity direction and in the opposite phase to the vibration phase of the sealed casing.
[0045]
  Claim 9The invention described inClaim 8In the invention described in the above, since the dynamic vibration absorber is formed in at least one of the upper space or the lower space in the sealed casing, the dynamic vibration absorber can be incorporated without increasing the size of the sealed casing. Has an effect.
[0046]
  Claim 10The invention described inClaim 8 or 9In the invention described in the above, since the weight of the dynamic vibration absorber has a substantially annular shape or a substantially arc shape along the inside of the sealed casing, the weight of the dynamic vibration absorber is increased. It can be made heavy, and has the effect of being able to reduce vibration at a low frequency.
[0047]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of a linear motor and a linear compressor according to the present invention will be described with reference to the drawings. In addition, about the same structure as the past, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.
[0048]
  (Reference Example 1)
  1 is a side sectional view of a linear motor according to Reference Example 1, FIG. 2 is a sectional view taken along line AA in FIG. 1, FIG. 3 is a schematic diagram showing an operation principle of the linear motor, and FIG. 4 is a plan view of a flexure bearing. FIG. 5 is a schematic diagram showing the direction of current flow of the linear motor.
[0049]
  1 to 5, the substantially cylindrical stator 22 accommodates two magnet wires 12a and 12b wound in a ring shape, and three independent magnet wires 12a and 12b and an inner periphery thereof. It consists of a fixed iron core 23 that forms a magnetic pole.
[0050]
  The fixed iron core 23 is magnetically non-directional and has a high magnetic permeability, for example, silicon steel plates represented by a non-directional electromagnetic steel strip of JIS C2352 are arranged radially with respect to the cylindrical axis. . The fixed iron core 23 is divided into three parts 23a, 23b, and 23c in the axial direction, each of which forms independent magnetic poles 23d, 23e, and 23f on the inner peripheral surface, and the magnet wires 12a and 12b wound in a ring shape in advance. Is assembled to sandwich.
[0051]
  The ends 12c, 12d, 12e, and 12f of the windings of the magnet wires 12a and 12b are provided with a gap in a part of the thin plate arranged radially of the fixed iron core 23 so that a current flows around the axis as shown in FIG. They are wired so that the flow directions are opposite to each other. Further, the end portions 12g and 12h are drawn out of the fixed iron core 23 by using electrically insulated conductive wires.
[0052]
  The mover 21 has a substantially cylindrical shape sharing an axis with the stator 22 and is housed inside the stator 22 so as to be swingable in the axial direction, and has a hollow cylindrical shape made of an iron-based material. The portion 21a and the thin plate portion 21b in which silicon steel plates represented by, for example, non-directional electromagnetic steel strips of JIS C2352 are radially arranged around the shaft center on the outer periphery of the core portion 21a are integrated. The movable core 24 formed in this manner, and the magnet 25a which is fixed to the outer periphery of the movable core 24 with an adhesive and the inner periphery of the stator 22 with an adhesive, is separated into two in the axial direction, and has different magnetic poles on the surface. , 25b. As the magnets 25a and 25b, magnets containing a rare earth element and having a strong magnetic field are used.
[0053]
  The movable shafts 26 a and 26 b are shafts that are fixed to the core portion 21 a and extend in the swing direction, and the frame body 27 fixedly supports the outer periphery of the stator 22. The movable shafts 26a and 26b are both made of a stainless material or the like that has a sufficiently large electric resistance compared to iron and is nonmagnetic.
[0054]
  The flexure bearings 28a and 28b respectively disposed on both sides of the swinging direction of the movable element 21 include eight arms 28c, 28d, 28e, which are formed by providing eight thin slits in a plate-like elastic material. The movable element 21 is supported by 28f, 28g, 28h, 28i, and 28j so as to be swingable in the swinging direction.
[0055]
  The flexure bearings 28a and 28b are connected and fixed to the frame body 27 at the outer peripheral portion and are connected and fixed to the movable shafts 26a and 26b at the inner peripheral portion, respectively. It has a so-called bearing characteristic that the rigidity of the direction is small. The rigidity in the radial direction and the axial direction varies depending on design factors such as the shape and arrangement of the arms, the material, and the material thickness, but at least supports the force that the mover 21 is attracted to the stator 22 by the magnetic attraction force. The mover 21 and the stator 22 are provided with a radial rigidity sufficient to ensure a constant gap over the entire circumference.
[0056]
  The magnets 25a and 25b and the magnetic poles 23d, 23e, and 23f are arranged so that the magnet 25a faces the electrodes 23d and 23e and the magnet 25b faces the magnetic poles 23e and 23f, respectively, even when the mover 21 swings. Has been. Further, the length of the mover 21 is selected so that it does not come out of the stator 22 when swinging, and the difference in length from the stator 22 substantially matches the maximum amplitude of the mover 21.
[0057]
  The operation of the linear motor configured as described above will be described below.
[0058]
  When an electric current is passed through the ring-shaped magnet wires 12a and 12b, first, a magnetic flux Φ that loops to the fixed iron core, the gap, the magnet, the movable iron core, the magnet, the gap, and the fixed iron core is generated as indicated by the arrows. By this magnetic flux Φ, the magnetic poles 23d, 23e, and 23f to the fixed iron core 23 are magnetized to the N pole, the S pole, and the N pole, respectively. Since the outer surfaces of the magnets 25a and 25b of the mover 21 are magnetized to the S and N poles, the attractive and repulsive forces shown in white are generated between the respective magnetic poles and the respective magnets. 21 is driven in the direction indicated by arrow a.
[0059]
  Next, when a reverse current flows through the magnet wires 12a and 12b, an operation opposite to that described above occurs, and the mover 21 is driven in the direction opposite to the arrow A. The reciprocating operation of the mover 21 is performed by controlling to alternately switch the direction and magnitude of the current.
[0060]
  Here, in the flexure bearings 28a and 28b, a minute rotational twist is generated in accordance with the reciprocating motion of the movable element 21, but the shape of the movable element 21 and the stator 22 is a cylindrical shape. Even if the mover 21 is absorbed and rotated, the stator 22 can maintain a constant spatial distance. Problems such as a decrease in efficiency and an increase in noise due to the contact and collision of the mover 21 and the stator 22 occur. Can be prevented. Further, the positional relationship between the mover 21 and the stator 22 only needs to be aligned with each other. For example, as compared with the case where the surface of the mover 21 is flat, it is easy to assemble so as to keep the gap constant. As a result, there is almost no bias in the magnetic attractive force by the magnets 25a and 25b acting between the mover 21 and the stator 22, and as a result, almost no radial load is generated.
[0061]
  In addition, since the load in the radial direction is supported by the flexure bearings 28a and 28b, sliding loss due to the swinging of the mover 21 does not occur compared to the case where a support mechanism such as a slide bearing is used. . Further, since almost no load is generated in the lateral direction, the rigidity in the radial direction necessary for the flexure bearings 28a and 28b to support the mover 21 is small, and the number of flexure bearings 28a and 28b is reduced. By performing a low-rigidity design such as reducing the thickness and reducing the number of arms, hysteresis loss when the flexure bearings 28a and 28b are deformed in the swing direction can be minimized, and high efficiency can be obtained. Can do. The hysteresis loss means a loss that occurs when the spring is taken as an example, and the energy accumulated inside the spring by compressing the spring cannot be completely extracted as a repulsive force that the spring extends.
[0062]
  In addition, since the magnets 25a and 25b are fixed to the outer periphery of the movable iron core 24, compared to the conventional movable magnet type linear motor, there is no gap between the magnets 25a and 25b and the movable iron core 24. There are few voids. As a result, since the magnetic resistance is reduced, the magnetic flux flows more easily than the movable magnet type, and the current to the magnet wires 12a and 12b that generates a constant magnetic flux to obtain the required thrust can be reduced, improving the efficiency. The amount of magnets can be reduced.
[0063]
  Further, since both the movable core 24 of the movable element 21 and the fixed core 23 of the stator 22 are composed of thin plates arranged radially around the axial direction, the extending direction of the thin plate and the magnetic flux direction coincide with each other, so While increasing the magnetic susceptibility, the induced current generated in the iron core can be suppressed and the loss can be reduced.
[0064]
  Also,This reference exampleTherefore, the magnets 25a and 25b are bonded to the surface of the movable iron core 24 with an adhesive and integrated with the mover 21, so that the strength of the brittle magnet itself can be supplemented. As a result, an expensive rare-earth magnet can be made thin, and the efficiency can be improved by reducing the weight of the movable part along with a significant cost reduction.
[0065]
  in additionThis reference exampleThen, the movable shafts 26a and 26b that support the movable element 21, the frame body 27 that supports the outer periphery of the stator 22, and the flexure bearings 28a and 28b are made of stainless steel that is a non-magnetic material. In addition to preventing leakage of magnetic flux that bypasses the movable shafts 26a and 26b via the frame body 27 and the flexure bearings 28a and 28b, it is possible to prevent generation of induced current due to the leakage magnetic flux and prevent reduction in efficiency of the motor. The same effect can be obtained even if a nonmagnetic material other than stainless steel such as plastic is used for these portions.
[0066]
  Further, since the fixed iron core 23 is divided into three blocks 23a, 23b, and 23c in the axial direction in a cross section including the storage portions of the magnet wires 12a and 12b, the magnet wires 12a and 12b wound in advance in a ring shape are sandwiched therebetween. As a result of such insertion, assembly becomes possible, and high production efficiency can be obtained.
[0067]
  In this reference example, the number of magnetic poles of the stator 22 is set to 3, and two magnets of the mover 21 are arranged in the axial direction. However, even if the number of magnetic poles of the stator is two, or four or more, the motor can be configured. Is possible. In this case, the magnet may be arranged on the mover by one less than the number of magnetic poles in the axial direction,This reference exampleThere is no change in the effect obtained with.
[0068]
  The movable iron core 24 of the mover 21 has a cylindrical core portion as an axis, and a thin plate having the same width is arranged around the periphery, so that a cylindrical shape can be easily formed.
[0069]
  Furthermore, since the core portion 21a of the mover 21 is made of an iron-based material, the mover 21 functions as a part of the magnetic path of the magnetic flux loop, so that the efficiency can be improved while reducing the weight of the mover 21.
[0070]
  Moreover, since the vicinity of the center of the core portion 21a, which has a small strength as a structure and a contribution as a magnetic path of the magnetic flux loop, is hollow, the mover 21 can be reduced in weight.
[0071]
  The direction of the magnetic flux is changed by 90 degrees in the fixed iron core 23a. Since the non-directional electromagnetic steel strip is used for the fixed iron core 23, the magnetic permeability is directional regardless of the direction of the magnetic flux. No significant reduction in efficiency occurs.
[0072]
  Further, by making the maximum value of the reciprocating distance of the mover 21 substantially coincide with the difference in length between the mover 21 and the stator 22, the magnets 25 a and 25 b of the mover 21 jump out of the stator 22 and the stator 22. The motor thrust is prevented from being reduced due to the action of the magnetic attractive force that is pulled back inside.
[0073]
  The flexure bearing of the present reference example is a plate-like elastic body provided with a spiral arm, but may have other shapes.
[0074]
  Moreover, although demonstrated as a linear motor, it can utilize also as a generator which converts reciprocating motion into an electric current with the completely same structure.
[0075]
  Further, although magnet wires wound in a ring shape are connected in series, they may be connected in parallel.
[0076]
  (Reference Example 2)
  6 is a cross-sectional view of a linear motor according to Reference Example 2. FIG. In FIG. 6, since it is the same structure as the reference example 1 except the needle | mover 21, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.
[0077]
  As shown in FIG. 6, magnets 29 a, 29 b, 29 c, 29 d having a substantially arc-shaped cross-sectional shape are disposed inside the movable iron core 24 and integrated with the mover 21.
[0078]
  Therefore, in addition to the above-described effects, the magnets 29a, 29b, 29c, and 29d are not exposed on the surface of the mover 21, and therefore the attractive force with the magnetic body is small, so that the assembly with the magnetic body becomes easy. Handling becomes easier, and mass productivity and productivity are greatly improved.
[0079]
  (Reference Example 3)
  FIG.Reference example 3It is sectional drawing of the linear motor by.
[0080]
  In FIG. 7, one end of each of the coil springs 30 a and 30 b is locked to the movable shafts 26 a and 26 b connected to the movable element 21, and the other end is locked to the spring holders 31 a and 31 b fixed to the frame body 27. . The length (L) when the coil springs 30a and 30b are assembled is shorter than the natural length (H), and the compression dimension (HL) is ½ or more of the swing distance of the mover 21, that is, the stroke (S). The mover 21 is assembled by being pressed from both sides by the coil springs 30a and 30b.
[0081]
  The coil springs 30a and 30b determine the resonance frequency determined by the mass relationship with the mover 21 as a total spring constant combined with the flexure bearings 28a and 28b.
[0082]
  All the components such as the reciprocating movable element 21, the movable shafts 26a and 26b, the coil springs 30a and 30b, and the stator 22 are housed in a substantially sealed space 31c configured by the frame body 27 and the spring holders 31a and 31b. ing.
[0083]
  Other portions are the same as those in Reference Example 1, and detailed description thereof is omitted.
[0084]
  The operation of the linear motor configured as described above will be described below.
[0085]
  When alternating current is passed through the ring-shaped magnet wires 12a and 12b,Reference example 1The reciprocating operation of the movable element 21 is performed based on the same principle as described above. For example, when the mover 21 moves in the direction of arrow B, the coil spring 30a is bent and a repulsive force is stored in the coil spring 30a.
[0086]
  Next, when the direction of current flow changes and the mover 21 moves in the direction of the arrow C, the repulsive force (A) is extracted from the coil spring 30a and recovered as the speed of the mover 21. At the same time, the coil spring 30b is bent and the repulsive force (B) is stored in the coil spring 30b. When the mover 21 moves again in the direction of arrow B, the repulsive force (B) is taken out from the coil spring 30b and moved. It is recovered as the speed of the child 21.
[0087]
  This operation is a so-called resonance action, and a reciprocating motion with a large stroke can be performed with a small current compared to when the coil springs 30a and 30b are not used. By matching the frequency of the power source at this time with the resonance frequency obtained from the mass of the mover 21 and the stator 22 and the spring constant of the coil springs 30a and 30b, the mover 21 and the coil springs 30a and 30b which are resonance springs are used. The period of acceleration is synchronized, and as a result, energy loss is kept small, and the mover 21 can be reciprocated efficiently.
[0088]
  In designing the resonance frequency in this resonance action, in order to increase the resonance frequency, the weight of the mover 21 is reduced, and the spring constants of the coil springs 30a and 30b and the flexure bearings 28a and 28b are increased. Although it is easy to cope with it, there is a design limit as a motor in reducing the weight of the mover 21, and in reality, it is often easier to increase the spring constant.
[0089]
  If the spring constants of the flexure bearings 28a and 28b are increased (for example, the thickness is increased or a plurality of sheets are stacked) in order to increase the spring constant, hysteresis loss increases and efficiency decreases. However, since the coil springs 30a and 30b basically have no hysteresis loss, by increasing only the coil springs 30a and 30b spring constant, it is possible to ensure high efficiency with a small hysteresis loss in a design in which the resonance frequency is increased. is there.
[0090]
  Further, the length (L) when the coil springs 30a and 30b are assembled is shorter than the natural length (H), and the compression dimension (HL) is the swing distance of the mover 21, that is, 1 / th of the stroke (S). 2 or more.
[0091]
  Therefore, even when the mover 21 moves to the maximum in the direction of arrow B, the length (Lb) of the coil spring 30b is shorter than the natural length (H), that is, the coil spring 30b is always compressed from the natural length. It will be.
[0092]
  Similarly, even when the mover 21 moves to the maximum in the direction of arrow C, the length (La) of the coil spring 30a is shorter than the natural length (H), that is, the coil spring 30a is always compressed from the natural length. There will be.
[0093]
  Therefore, even if the mover 21 reciprocates, the coil springs 30a and 30b are always compressed more than the natural length, so that the coil springs 30a and 30b can be generated by the energy stored by the deformation without using any special fixing means. 30b can be locked in a bent state between the movable shafts 26a and 26b and the spring holders 31a and 31b, and does not fall off.
[0094]
  Furthermore, all the components such as the reciprocating movable element 21, the movable shafts 26a and 26b, the coil springs 30a and 30b, and the stator 22 are contained in a substantially sealed space 31c constituted by the frame body 27 and the spring holders 31a and 31b. Since it is housed, the noise associated with the movement of the mover 21, the movable shafts 26a and 26b, and the coil springs 30a and 30b is kept in the substantially sealed space 31c, and a so-called sound insulation effect is obtained that reduces the transmission of noise to the outside. be able to.
[0095]
  Further, since both the movable iron core 24 of the mover 21 and the fixed iron core 13 of the stator 22 are composed of thin plates arranged radially around the axial direction, the component parts vibrate, resulting in vibration. Although noise from a thin plate may occur, this noise can also be insulated.
[0096]
  still,This reference exampleIn FIG. 2, the coil springs 30a and 30b are the same spring having the same spring constant. However, even when coil springs having different spring constants and dimensions are combined, the same can be implemented.
[0097]
  (Embodiment 1)
  FIG. 8 illustrates the present invention.Embodiment 1It is sectional drawing of the linear compressor by.
[0098]
  In FIG. 8, the outer peripheral portions of the flexure bearings 28 a and 28 b are fixed by being sandwiched between spring holders 31 a and 31 b and a frame body 27 that supports the stator 22. Further, the inner peripheral portions of the flexure bearings 28a and 28b are locked to movable shafts 26a and 26b connected to the movable element 21 and spring adapters 32a and 32b.
[0099]
  The coil springs 30a and 30b are disposed on both end sides with the linear motor 37 composed of the movable element 21 and the stator 22 interposed therebetween, and are further locked in a bent state between the spring adapters 32a and 32b and the spring holders 31a and 31b. Therefore, no special fixing means is used. However, in order to lock the coil springs 30a and 30b at the centers of the spring adapters 32a and 32b and the spring holders 31a and 31b, a slight step is provided on the contact surface with the coil springs 30a and 30b.
[0100]
  The cylinder 33 is fixed to the spring holder 31 b, and the cylinder cover 34 is fixed to the cylinder 33.
[0101]
  The spring adapter 32b is connected to the piston 36 via the ball joint 35, and the piston 36 can freely tilt and rotate with respect to the spring adapter 32b. The compression chamber 38 includes a piston 36 and a cylinder 33.
[0102]
  The operation of the linear compressor configured as described above will be described below.
[0103]
  When an alternating current is passed through the magnet wires 12 a and 12 b of the linear motor 37, the mover 21 reciprocates with respect to the stator 22, and the driving force is applied to the piston 36 via the movable shaft 26 b, the spring adapter 32 b and the ball joint 35. And the piston 36 reciprocates integrally with the mover 21. Then, the reciprocating motion of the piston 36 sequentially compresses the refrigerant gas sucked into the compression chamber 38 and discharges it to the external refrigeration cycle.
[0104]
  At this time, as described in Reference Example 2, the frequency of the power source energizing the linear motor 37 should be matched with the resonance frequency obtained from the masses of the mover 21 and the stator 22 and the spring constants of the coil springs 30a and 30b. Thus, the cycle of acceleration from the mover 21 and the coil springs 30a and 30b, which are resonance springs, is synchronized. As a result, the energy loss is kept small, and the mover 21 can be reciprocated efficiently.
[0105]
  In particular, since the movable element 21 is supported at both ends by the flexure bearings 28a and 28b, a sliding loss due to the swinging of the movable element 21 occurs as compared with the case where a support mechanism such as a slide bearing is used. do not do. Further, with respect to hysteresis loss when the flexure bearings 28a and 28b are deformed, the radial rigidity required for the flexure bearings 28a and 28b is small, the number of flexure bearings is reduced, the thickness is reduced, the number of arms By performing a low-rigidity design such as reducing the amount of noise, it can be minimized and high efficiency can be obtained.
[0106]
  Further, since all the magnetic attractive force acting in the radial direction of the mover 21 is supported at both ends by the flexure bearings 28a and 28b, the magnetic attractive force generated between the mover 21 and the stator 22, that is, movable The force that the child 21 is attracted to the stator 22 in the radial direction acts as a side pressure of the piston 36 and the cylinder 33, and no sliding loss occurs. Therefore, high efficiency can be achieved by reducing sliding loss, and the reliability of the sliding portion is greatly improved.
[0107]
  Further, since the magnetic attractive force acting in the radial direction of the mover 21 does not act as a side pressure of the piston 36 and the cylinder 33, a ball joint is provided between the spring adapter 32 b that transmits the reciprocating motion of the mover 21 to the piston 36 and the piston 36. Even if 35 is provided, the piston 36 can be supported. Therefore, when the piston 36 reciprocates in the cylinder 33, the piston 36 can be tilted by the ball joint 35 so as to swing with little axial tilt with respect to the sliding portion of the cylinder 33.
[0108]
  Therefore, even if the axis of the mover 21 and the cylinder 33 is displaced or the shaft is assembled with the axis inclined, the ball joint can absorb the axis deviation and the axis inclination so that the axes of the piston 36 and the cylinder 33 are aligned. In addition, the efficiency of the compressor can be increased by reducing the sliding loss due to the reduction of the side pressure between the cylinder 33 and the piston 36 without improving the accuracy of components and component assembly.
[0109]
  (Embodiment 2)
  FIG. 9 illustrates the present invention.Embodiment 2It is principal part sectional drawing of the linear compressor by. In FIG. 9, the linear motor 37 and the likeEmbodiment 1Since the configuration is the same as in FIG. 8, the same reference numerals are given and detailed description thereof is omitted.
[0110]
  In FIG. 9, the piston 39a has at least part of a thin rod 40 having a small radial rigidity and easily elastically deformable in the radial direction, such as a thin rod, and a flexure bearing 28b. It is connected with the mover 21 through the movable shaft 26b.
[0111]
  The retractable rod 40 is made of a material such as stainless steel or aluminum in terms of strength and the like, and has a relatively thin portion with a circular cross-sectional shape. By providing this thin portion, the retractable rod 40 can fall within a range of elastic deformation in a direction inclined with respect to the axial direction.
[0112]
  In addition, most of the refrigerant gas discharged into the high-pressure chamber 34a in the cylinder cover 34 is discharged outside the compressor via the D line 41, and some of the refrigerant gas passes through the plurality of communication passages 43 provided in the cylinder 42a. The gas bearing 47 is formed by being guided to the sliding portion between the piston 39a and the cylinder 42a. Furthermore, no lubricating oil is used.
[0113]
  In the high pressure chamber 34a in the cylinder cover 34, a discharge valve mechanism 44 and a discharge spring 45 that urges the discharge valve mechanism 44 to the cylinder 42a are disposed.
[0114]
  The second suction pipe 46 has one end 46 a opened in the spring holder 31 b in the vicinity of the cylinder 42 a near the non-compression chamber, and the other end 46 b opened in the sealed casing 47. A suction passage 39b is provided in the piston 39a, and a suction valve mechanism 39c is attached to the compression chamber 38 side of the piston 39a.
[0115]
  About the linear compressor comprised as mentioned above, the operation | movement is demonstrated below. In addition, about the content similar to other embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.
[0116]
  Since all the magnetic attractive force acting in the radial direction of the mover 21 is supported at both ends by the flexure bearings 28a and 28b, the member that transmits the reciprocating motion of the mover 21 to the piston 39a generates the magnetic attractive force. There is no need to support, only the axial rigidity is required, and the radial rigidity may be small.
[0117]
  Therefore, by connecting the piston 39a and the mover 21, by using a retractable rod 40 made of an elastic body, which has a small radial rigidity, such as a thin rod, and can be easily elastically deformed in the radial direction, Even if the axis of the mover 21 and the cylinder 42a is displaced or the shaft is assembled with an inclination, the tiltable rod is inclined or bent so that the axes of the piston 39a and the cylinder 42a are aligned and there is no axis inclination. As a result, it is possible to absorb defects in component accuracy and component assembly accuracy.
[0118]
  Accordingly, the side pressure between the cylinder 42a and the piston 39a can be reduced without improving the accuracy of parts and parts assembly, and the efficiency of the compressor can be improved by reducing the sliding loss. Reliability is further improved.
[0119]
  Furthermore, the retractable rod 40 has a simple structure as compared with a ball joint mechanism and the like, and since there are not even a few sliding portions like the ball joint mechanism, the sliding loss is small and the connection mechanism is reliable. The nature is also high.
[0120]
  In addition, it is an oil-free configuration that does not use lubricating oil, so that the amount of refrigerant used in the cooling system can be reduced and the amount of refrigerant used in the cooling system can be reduced, and the efficiency of heat exchange in the cooling system is improved. The overall efficiency of the cooling system is improved. Furthermore, when a natural refrigerant or a flammable refrigerant is used, the amount of refrigerant used can be reduced, so that the possibility of ignition or explosion when the refrigerant leaks is reduced, and safety is improved.
[0121]
  Further, a part of the refrigerant gas discharged into the high-pressure chamber 34a in the cylinder cover 34 passes through a plurality of communication passages 43 provided in the cylinder 42a so that the sliding portion between the piston 39a and the cylinder 42a is very small. A gas film is formed through the gap (so-called gas bearing 47), and the piston 39a and the cylinder 42a are brought into a non-contact state.
[0122]
  The performance of the gas bearing 47 is generally evaluated as to how much non-contact can be achieved with a small amount of gas and low gas pressure. However, depending on the shape, dimensions, installation position, etc. of the communication passage 43, the gas It has been confirmed that the performance of the bearing 47 changes greatly, and the result that it is desirable to dispose a small cross-sectional area corresponding to a cross-sectional area of φ30 μm to φ200 μm at least in a part of the communication path 43 is obtained. ing. For this reason, in operation in which lubricating oil is present, this minute cross-sectional area is clogged with lubricating oil and refrigerant gas does not flow, and the gas bearing 47 does not function. Therefore, the gas bearing 47 is used without using lubricating oil.
[0123]
  As described above, since the piston 39a and the cylinder 42a can be brought into a non-contact state, the sliding loss between the piston 39a and the cylinder 42a can be reduced to almost zero, and the reliability such as wear of the sliding portion is greatly increased. improves. The effect is larger as the compressor has a higher operating frequency and higher sliding loss.
[0124]
  Although the sliding loss can be reduced to almost zero as described above, since the refrigerant gas is guided to the sliding portion of the piston 39a and the cylinder 42a, the leakage loss of the sliding portion increases, and the compressed high-pressure gas is supplied to the gas bearing 47. Therefore, the compression loss also increases. However, the loss can be reduced as a design element based on the design know-how of the gas bearing 47 described above.
[0125]
  (Embodiment 3)
  FIG. 10 illustrates the present invention.Embodiment 3It is principal part sectional drawing of the linear compressor by. In FIG. 10, the linear motor 37 and the like areEmbodiment 1Fig. 8 andEmbodiment 29 are the same as those shown in FIG.
[0126]
  In FIG. 10, a self-lubricating material 47a is used for the piston 39d, and a ceramic material 47b is used for the cylinder 42b.
[0127]
  Therefore, even when the gas bearing 47 is not used, due to the self-lubricating effect and the wear resistance of the ceramic material 47b, the wear of the sliding portion can be prevented even in the operation without using the lubricating oil, and the reliability is ensured. be able to.
[0128]
  The refrigerant gas sucked into the sealed casing 48 is guided to the vicinity of the anti-compression chamber side of the cylinder 42b through the second suction pipe 46, and the anti-compression chamber side of the cylinder 42b, the anti-compression chamber side of the piston 39d, Then, the air flows into the compression chamber 38 through a suction passage 39a and a suction valve mechanism 39b provided in the piston 39d.
[0129]
  The refrigerant gas compressed in the compression chamber 38 is opened by overcoming the urging force of the discharge spring 45 that urges the discharge valve mechanism 44 to the cylinder 42 b, and is discharged to the high-pressure chamber 34 a in the cylinder cover 34.
[0130]
  At this time, during a transient operation in a cooling system such as a refrigerator, there is always a fluctuation in the operating pressure, and in such a case, the piston 39d reciprocates beyond a predetermined stroke. Further, when the operating current or operating voltage of the compressor is controlled, the piston 39d reciprocates beyond a predetermined stroke due to the control accuracy and the disturbance response accuracy.
[0131]
  However, even in that case, since the piston 39d can swing by pushing away the discharge valve mechanism 44, the impact force of the collision applied to the piston 39d can be reduced compared to the discharge valve mechanism that cannot push away. Therefore, noise at the time of the collision of the piston 39d can be reduced, and the reliability of the discharge valve mechanism 44 and the piston 39d can be improved.
[0132]
  (Embodiment 4)
  FIG. 11 shows the present invention.Embodiment 4It is sectional drawing of the linear compressor by.
[0133]
  In FIG. 11, the linear motor 37 and the likeEmbodiment 29 are the same as those shown in FIG.
[0134]
  In FIG. 11, a compression mechanism 49 is vertically arranged in a hermetic casing 48 so that the swinging direction of the mover 21 coincides with the direction of gravity, and is internally suspended by a plurality of suspension springs 50 and a top spring 51. Is supported internally.
[0135]
  The dynamic vibration absorber 52 includes a weight 53, a spring 54, and a holder 55, and is formed in an upper space inside the sealed casing 48. The weight 53 is composed of a single or a plurality of weights, and the shape thereof is a substantially annular shape or a substantially arc shape along the inside of the sealed casing 48, or a substantially annular shape or a substantially arc shape.
[0136]
  In the assembled state or in a state where the linear compressor is stopped, the springs 54a and 54b are both shorter than the natural length and in a compressed state. Therefore, the weight 53 is clamped by the spring force of the springs 54a and 54b in the same direction as the swinging direction of the piston 39a and is integrally attached to the holder 55. The shape of the holder 55 is also a substantially annular shape or a substantially arc shape.
[0137]
  As the weight 53 moves, the spring 54 can be elastically deformed in the swinging direction of the piston 39a. Further, the sum of the weight of the weight 53 and the spring constant of the spring 54 in the direction of swinging of the spring 54 is selected so that the resonance frequency determined therefrom matches the operating frequency of the linear compressor.
[0138]
  Further, the cylinder 42a is inserted and arranged in the coil spring 30b.
[0139]
  About the linear compressor comprised as mentioned above, the operation | movement is demonstrated below. Note that detailed description of the same contents as in the other embodiments is omitted.
[0140]
  Since the movable element 21 is vertically arranged so that the swinging direction thereof coincides with the direction of gravity, the force acting in the radial direction of the movable element 21 is magnets 25 a and 25 b acting between the movable element 21 and the stator 22. Only the magnetic attraction force due to, and the gravity of the mover 21 does not act.
[0141]
  Therefore, the rigidity in the radial direction of the flexure bearings 28a and 28b supporting the mover 21 and supporting the magnetic attractive force can be reduced because the gravity of the mover 21 does not act. For example, it is possible to select an inexpensive material, reduce the plate thickness, simplify the shape, reduce the size, and the like.
[0142]
  Similarly, in the sliding portion between the cylinder 42a and the piston 39a, the side pressure due to gravity does not act on the piston 39a, so that the sliding loss can be reduced accordingly.
[0143]
  Next, the vibration reduction by the dynamic vibration absorber 52 will be described.
[0144]
  The mover 21 reciprocates with respect to the stator 22 to perform compression. At this time, the stator 22 of the compression mechanism 49 vibrates in the reciprocating direction of the piston 39a due to the reaction of the reciprocation of the mover 21. The compression mechanism 49 is elastically suspended in the sealed casing 1 by a suspension spring 50, and vibration of the compression mechanism 49 is transmitted to the sealed casing 48 as an excitation force via the suspension spring 50. Due to the excitation force transmitted to the hermetic casing 48, the resonance system composed of the weight 53 and the spring 54 is excited, and the weight 53 vibrates in the reciprocating direction of the piston 39a. At this time, the excitation force transmitted from the suspension spring 50 to the sealed casing 48 and the magnitude of the action force due to the vibration of the weight 53 are substantially equal and operate in opposite phases. Therefore, the excitation force from the compression mechanism 49 is a dynamic vibration absorption. Counteracted by the acting force from the vessel 52.
[0145]
  Further, since the vibration frequency of the sealed casing 48 matches the driving frequency of the linear compressor, the effect of the dynamic vibration absorber 52 can be obtained by matching the driving frequency of the linear compressor and the oscillation frequency of the weight 53 of the dynamic vibration absorber 52. The vibration of the sealed casing 48 can be reduced to the maximum by pulling out to the maximum. Specifically, the mass of the weight 53 and the spring 54 are set such that the resonance frequency determined by the mass of the weight 53 of the hermetic casing 48 and the dynamic vibration absorber 52 and the spring constant of the spring 54 matches the drive frequency of the linear compressor. By selecting and designing the spring constant, vibration can be reduced to the maximum.
[0146]
  Even when the dynamic vibration absorber 55 is not used, since the swinging direction of the mover 21 and the expansion / contraction direction of the suspension spring 50 coincide with each other in the gravitational direction by adopting the vertical arrangement, the vibration direction of the sealed casing 48 is also the same. Gravity direction. Therefore, the transmission of the vibration of the compression mechanism 48 to the sealed casing 48 is reduced by a simple method such as reducing the rigidity of the suspension spring 50, and although not as much as when the dynamic vibration absorber 52 is attached, the piston 39a. The vibration of the sealed casing 48 can be greatly reduced compared to the horizontal arrangement in which the reciprocating direction is horizontal.
[0147]
  Further, the above-described dynamic vibration absorber 52 is formed in the upper space of the sealed casing 48. The linear motor 37 is the largest in the radial direction in the compression mechanism portion 49 and determines the size in the radial direction, but the linear motor 37 is not disposed in the upper space of the sealed casing 48.
[0148]
  Therefore, an invalid space is formed in the upper space and the lower space with respect to the size of the sealed casing 48 in the radial direction. By forming the dynamic vibration absorber 52 in this space, the size of the sealed casing 48 is increased. Without increasing the size, the dynamic vibration absorber 52 is built in in a compact manner, and low vibration can be achieved.
[0149]
  In particular, similarly to the circular shape of the linear motor 37 and the circular shape of the sealed casing 48, the size of the closed casing 48 is increased by making the shape of the dynamic vibration absorber 52 a substantially annular shape or a substantially arc shape along the inside of the sealed casing 48. The dynamic vibration absorber 52 can be incorporated in a compact manner without increasing the size. Furthermore, the weight 53 of the dynamic vibration absorber 52 can be increased, that is, heavier, and the design width of the resonance frequency determined by the mass of the weight 53 of the sealed casing 48 and the dynamic vibration absorber 52 and the spring constant of the spring 54 is increased. be able to. Therefore, the width of the driving frequency that can reduce the vibration of the sealed casing 48 by the dynamic vibration absorber 52 is widened, and the operating frequency width of the linear compressor that can be driven with low vibration can be increased.
[0150]
  Furthermore, since at least a part of the cylinder 42a is inserted and arranged in the coil spring 30b, the size of the compression mechanism 49 in the swinging direction of the movable element 21 is smaller than when the cylinder 42a is arranged outside the coil spring 30b. can do. Therefore, it is possible to reduce the size of the sealed casing 48 as a linear compressor, particularly to reduce the size of the movable element 21 in the swinging direction.
[0151]
  In the present embodiment, the dynamic vibration absorber 52 is formed in the upper space in the sealed casing 48, but the same effect can be obtained even if it is formed in the lower space in the sealed casing 48.
[0152]
  In this embodiment, the linear motor is arranged above the gravitational direction. However, the present invention can be similarly implemented even if the linear motor is arranged below the gravitational direction.
[0153]
【The invention's effect】
  As described above, the invention described in claim 1 has an effect of being able to achieve low cost and high efficiency.
[0154]
  Furthermore, high efficiency can be achieved as a compressor.Easy and high reliability can be ensuredThere is an effect.
[0155]
  Also,Claim 2The invention described in 1 is effective in that the amount of refrigerant used in the cooling system can be reduced and the efficiency of the entire system is improved.
[0156]
  Also,Claim 3The invention described in (1) has the effect that the sliding loss can be reduced to almost zero and the reliability such as the wear of the sliding portion is hardly present.
[0157]
  Also,Claim 4The invention described in (3) has the effect that sliding part wear can be prevented without using lubricating oil due to the self-lubricating effect.
[0158]
  Also,Claim 5The invention described in (3) has an effect that the wear of the sliding part can be prevented without using a lubricating oil due to the wear resistance of the ceramic material.
[0159]
  Also,Claim 6The invention described in 1 has an effect that the hermetic casing can be downsized as a linear compressor.
[0160]
  Also,Claim 7The invention described in (3) has an effect that the sliding loss can be reduced in addition to the reduction in size and cost of the flexure bearing.
[0161]
  Also,Claim 8The invention described in 1 has an effect that the vibration of the sealed casing can be reduced.
[0162]
  Also,Claim 9The invention described in 1 is effective in that the dynamic vibration absorber can be incorporated without increasing the size of the sealed casing.
[0163]
  Also,Claim 10The invention described in 1 is effective in that the weight of the dynamic vibration absorber can be increased without increasing the size of the sealed casing, and the vibration can be reduced at a low frequency.
[Brief description of the drawings]
FIG. 1 is a sectional view of a linear motor according to Reference Example 1.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
3 is a schematic diagram showing the operating principle of the linear motor of Reference Example 1. FIG.
FIG. 4 is a plan view of the flexure bearing of Reference Example 1.
FIG. 5 is a schematic diagram showing the current flow of the linear motor of Reference Example 1.
6 is a sectional view of a linear motor according to Reference Example 2. FIG.
[Fig. 7]Sectional view of a linear motor according to Reference Example 3
FIG. 8 shows a linear compressor according to the present invention.Embodiment 1Cross section of
FIG. 9 shows a linear compressor according to the present invention.Embodiment 2Sectional view of the main part of
FIG. 10 shows a linear compressor according to the present invention.Embodiment 3Sectional view of the main part of
FIG. 11 shows a linear compressor according to the present invention.Embodiment 4Cross section of
FIG. 12 is a cross-sectional view of a conventional linear compressor
13 is an enlarged view of the main part of FIG.
[Explanation of symbols]
  12a, 12b Magnet wire
  21 Mover
  22 Stator
  23 Fixed iron core
  23d, 23e, 23f Magnetic pole
  24 Movable iron core
  25a, 25b Magnet
  26a, 26b movable shaft
  28a, 28b flexure bearing
  29a, 29b, 29c, 29d Magnet
  30a, 30b coil spring
  31a, 31b Spring holder
  31c Almost sealed space
  33 cylinders
  35 ball joint
  36 piston
  37 Linear motor
  39a, 39d piston
  40 retractable rod
  42a, 42b cylinder
  47 Gas bearing
  47a Self-lubricating material
  47b Ceramic materials
  48 Sealed casing
  52 Dynamic vibration absorber
  53 weights
  54 Spring

Claims (10)

A stator having at least two magnetic poles and having a fixed iron core and a magnet wire engaged with the fixed iron core; a mover having a movable iron core and a magnet located inside the stator; and a substantially plate A flexure bearing that supports the mover in a swinging direction by a plurality of arms formed on a cylindrical elastic material, and a magnetic pole formed on the inner side of the stator; an outer peripheral surface of the mover; Has a substantially cylindrical shape sharing the axis of the swinging direction of the movable element, one end is locked to the movable element or a movable shaft extending to the axial center of the movable element, and the other end is the A coil spring that is locked to a spring holder fixed to a stator, and the flexure bearing supports a force by which the mover is attracted to the stator by a magnetic attraction force, and the mover and the stator are A constant gap over the entire circumference A resonance frequency determined by a relationship between a spring constant of a sum of the coil springs having a radial rigidity to be maintained and a spring constant larger than that of the flexure bearing and the flexure bearing and a mass of the stator and the mover. A piston mounted with a linear motor that is operated , and that shares a shaft center with the mover; and a piston that is reciprocally inserted into the cylinder and connected to the mover. A linear compressor in which the mover is connected via a retractable rod made of an elastic body. The linear compressor according to claim 1 , wherein no lubricating oil is used. Linear compressor according to claim 1 or 2 the sliding portion between the cylinder and the piston is constituted by a gas bearing. The linear compressor according to claim 2 , wherein a self-lubricating material is used for at least one of the cylinder or the piston. The linear compressor according to claim 2 , wherein a ceramic material is used for at least one of the cylinder or the piston. The linear compressor according to claim 1, wherein at least a part of the cylinder is inserted and disposed in a coil spring. The linear compressor according to any one of claims 1 to 6 , wherein a swinging direction of the mover coincides with a gravity direction. The linear compressor according to claim 7 , wherein a dynamic vibration absorber including a spring that is elastically deformable in a swinging direction of the mover and a weight attached to the spring is attached to the hermetic casing. The linear compressor according to claim 8 , wherein the dynamic vibration absorber is formed in at least one of an upper space and a lower space in the sealed casing. The linear compressor according to claim 8 or 9 , wherein a shape of the weight of the dynamic vibration absorber is a substantially annular shape or a substantially arc shape along the inside of the sealed casing.

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