JP5098499B2 - Linear compressor for regenerative refrigerator - Google Patents

Description

  The present invention relates to a linear compressor for a regenerative refrigerator that compresses gas with a piston driven by a linear motor.

  The linear compressor of the prior art is disposed in a magnetic field of a magnetic circuit provided in a piston, a fixed body having a piston that can reciprocate inside the machine, a magnet that forms a magnetic circuit using the fixed body as a yoke, and a piston. The fixed motor includes a first yoke portion facing one side of the coil and a second yoke portion facing the other side of the coil. And the magnet is provided in the first yoke portion and protrudes from the first yoke portion toward one side of the coil, and the second yoke portion is provided in the second yoke portion. And a second magnet protruding toward the other side of the coil (for example, Patent Document 1).

It also has a displacer that moves the working gas between the compression space and the expansion space, and a piston that reciprocates in the cylinder by a linear actuator (linear motor), and the displacer reciprocates when the piston reciprocates. In a Stirling engine designed to cause gas movement, one displacer is fixed to each end of one shaft, and a piston is placed between these displacers, and this piston acts on both displacers. There is a Stirling engine as described above (for example, Patent Document 2).
Japanese Patent No. 2626364 Publication 2005-36682

  However, according to Patent Document 1, in the magnetic circuit formed of the first magnet, the coil, the second magnet, the second yoke portion, the coupling portion, and the first yoke portion, Since the coil arranges the coil between the first magnet and the second magnet, both the thickness of the coil and the thickness of the bobbin around which the coil is wound are set between the first magnet and the second magnet. There is a problem that a gap larger than the added thickness must be provided, and this gap becomes a magnetic resistance of the magnetic circuit, reducing the efficiency of the linear motor and reducing the efficiency of the compressor.

  According to Patent Document 2, it is desirable that the efficiency of the regenerative refrigerator is operated at a low frequency with little gas pressure loss and mechanical loss. On the other hand, since the linear actuator has to do a lot of work with a small force, it has to be operated at a high frequency of 60 Hz, for example, and there is a problem that the efficiency of the refrigerator is sacrificed.

  The present invention has been made in view of the above problems, and provides a linear compressor for a regenerative refrigerator that is driven with high efficiency at an operating frequency at which high refrigerating efficiency of the regenerative refrigerator is obtained. Objective.

In order to solve the above-mentioned problem, the invention described in claim 1
An external stator having a coil on an external yoke of magnetic material, a movable body that reciprocates with respect to the external stator and having a piston on an internal yoke of magnetic material, and either the internal yoke or the external yoke. A linear motor comprising a permanent magnet;
A cylinder part including a cylinder of a non-magnetic material that is slidably circumscribed by the movable body and is fitted to the inner peripheral surface side of the external stator;
A compression space formed by the cylinder part and the piston;
A linear compressor for a regenerative refrigerating machine having a buffer space formed by the movable body and a cylinder portion opposite to the piston,
The linear compressor is connected to a refrigeration generator of the regenerator type refrigerator,
An adjustment member that makes the resonance frequency of the linear compressor variable is added to the movable body ,
A hole is formed in the internal yoke, and when the regenerative refrigerator operating frequency is higher than the resonance frequency, an internal stator made of a magnetic material fixed to the cylinder portion is removably inserted into the hole. A linear compressor for a regenerator type refrigerator is provided.

According to a second aspect of the present invention, at least one of the adjusting member and the piston is a non-magnetic material.

  According to the first aspect of the present invention, an alternating current is applied to a coil of a linear motor including a permanent magnet, a movable body including a piston is reciprocated, and a gas is compressed in a compression space. A vibration system is formed by the action of the combined spring formed by the gas spring in the compression space, the gas spring in the buffer space, and the magnetic spring generated by the linear motor, and the mass of the movable body. The spring / mass vibration system of this linear compressor has a unique resonance frequency. When operated near this resonance frequency, the stroke of the movable body becomes large and the gas is compressed with high efficiency. When the mass of the movable body is increased or decreased, the resonance frequency of the linear compressor changes. Therefore, the mass of the movable body can be increased or decreased so that the resonance frequency of the linear compressor matches the frequency of the regenerative refrigerator, and a linear compressor for a regenerative refrigerator that is driven with high efficiency can be provided.

  Further, the outer yoke and the inner yoke, and the outer yoke and the permanent magnet are formed with a magnetic circuit through a cylinder and a gap between the cylinder and the movable body, and the cylinder thickness of the cylinder is reduced, By minimizing the width of the gap, the magnetic gap between the outer yoke and the inner yoke and the magnetic gap between the outer yoke and the permanent magnet can be reduced. These magnetic gaps are the conventional coil-movable linear motors. This is smaller than the magnetic gap generated by the coil arrangement, improves the efficiency compared to the conventional coil movable linear motor, and increases the efficiency of the linear compressor for the regenerative refrigerator.

Furthermore , when the operating frequency of the regenerative refrigerator is higher than the resonance frequency of the linear compressor, the magnetic material internal stator fixed to the cylinder part reciprocates with a small gap from the hole provided in the internal yoke. By movably inserting, the mass of the hole provided in the inner yoke and the mass of the movable body are reduced, and the resonance frequency of the linear compressor becomes higher than when no hole is provided in the inner yoke. It can be adjusted to the operating frequency of the type refrigerator. Therefore, it is possible to provide a linear compressor for a regenerative refrigerator that is driven with high efficiency.

  Since the internal stator is a magnetic material, the magnetic flux of the linear motor hardly passes through the gap between the internal yoke and the internal stator and the internal stator and causes magnetic saturation. By reducing the cylinder wall thickness of the cylinder and reducing the width of the gap between the cylinder and the movable body, the magnetic resistance between the external stator and the movable body is reduced for the same reason as in claim 1, and By reducing the gap between the inner yoke and the inner stator, the magnetic resistance due to the gap is also reduced, and the efficiency is improved over the conventional coil-movable linear motor, and the linear compressor for the regenerative refrigerator is used. Increases efficiency.

Further, in the invention according to claim 2 , since at least one of the adjusting member and the piston is a non-magnetic material, at least one of the adjusting member and the piston hardly flows magnetic flux, and wasteful leakage magnetic flux is reduced. The efficiency of the linear compressor for the cold storage refrigerator is increased.

  The present invention will be described in detail below with reference to the drawings of the embodiments of the present invention.

Example 1
FIG. 1 is a cross-sectional view in which a refrigeration generator is connected to a linear compressor for a regenerative refrigerator according to the present invention, and shows a case where a permanent magnet is provided on an internal yoke. In detail, it is a figure which shows the adjustment which adjusts the resonance frequency of a linear compressor to the operating frequency which makes the refrigerating efficiency of a cool storage type refrigerator high.

It is a figure which shows adjustment of the resonance frequency corresponding to the case where the operation frequency which raises the refrigerating efficiency of a cool storage type refrigerator is lower than the resonance frequency of a linear compressor.

  The regenerative refrigerator 20a has a refrigeration generator 18 connected to the linear compressor 20, and the linear compressor 20 includes the cylinder portion 1, the external stator 6 of the linear motor 5 that fits outside the cylinder portion 1, and the cylinder portion. 1 and a movable body 10 of a linear motor 5 that is slidably inserted into the body 1.

  The cylinder portion 1 includes a cylindrical cylinder 2, a head 3 that is airtightly fixed to both ends of the cylindrical cylinder 2, and a cap 4, and the head 3 includes a flow path hole 3 a through which a gas flows. .

  The external stator 6 of the linear motor 5 includes an outer yoke 8 and a coil 7 made of a magnetic material. The outer yoke 8 has a substantially U-shaped cross section, and the outer yoke 8 is externally fixed to the outer peripheral surface of the cylinder 2 in a ring shape. The coil 7 has a conducting wire wound around the axis of the cylinder 2 and is mounted in a substantially U-shaped groove of the outer yoke 8. In the external stator 6 of the linear motor 5 described above, the outer yoke 8 made of a magnetic material may be divided into two in the radial axis direction.

  The movable body 10 of the linear motor 5 is disposed on the inner yoke 11 of a substantially columnar magnetic material, a cylindrical permanent magnet 12 bonded to a groove provided on the center outer periphery of the inner yoke 11, and the inner yoke 11. A piston 13 and an adjustment member 14 are provided. The permanent magnet 12 is magnetized in the radial direction, for example, the outer peripheral surface side is an N pole and the inner peripheral surface side is an S pole. A non-magnetic piston and a non-magnetic adjusting member 14 are fixedly engaged with the convex portions at both ends of the inner yoke 11. Also, a resin sliding material rider ring 11a is bonded to the outer peripheral surfaces of both ends of the inner yoke 11, and the outer peripheral surface of the rider ring 11a has a minute gap (for example, approximately 0.02 mm) with respect to the inner peripheral surface of the cylinder 2. ) And can slide smoothly, and the outer peripheral surfaces of the inner yoke 11, the permanent magnet 12, the piston 13, and the adjusting member 14 are prevented from coming into contact with the inner peripheral surface of the cylinder 2.

  The piston 13 is provided with a piston ring 13 a made of a resin sliding material, and a compression space 15 is formed from the piston 13, the piston ring 13 a, and the cylinder portion 1. In addition, a buffer space 16 is formed from the cylinder portion 1, the movable body 10 including the adjustment member 14, and the piston ring 13 a.

  The compression space 15 is connected to a refrigeration generator 18 of a regenerator chiller 20 a such as a Stirling refrigerator or a pulse refrigerator from a flow path hole 3 a of the head 3 through a pipe 17. Filled with helium.

  FIG. 2 is a cross-sectional view in which a refrigeration generating unit is connected to a linear compressor for a regenerative refrigerator according to the present invention, and shows a case where a permanent magnet is provided in an internal yoke. In detail, it is a figure which shows adjustment of the resonant frequency corresponding to the case where the operating frequency which makes the refrigerating efficiency of a cool storage type refrigerator high is higher than the resonant frequency of a linear compressor. In FIG. 2, the external stator, the cylinder portion, and the constituent members thereof are the same as those in FIG.

  The linear compressor 40 of the regenerative refrigerator 40a shown in FIG. 2 differs from the linear compressor 20 of FIG. 1 in that the structure of the movable body 30 of the linear motor 35 is different and a new internal stator 34 is provided. It is that. That is, the magnetic material inner yoke 31 is provided with a through hole 31b, and the magnetic material inner stator 34 is inserted into the inner peripheral surface of the hole 31b with a small gap (for example, approximately 0.05 mm). The internal stator 34 is fixed to the recess of the cap 4.

  A piston 33 made of a non-magnetic material is mated and fixed to the convex on one end side of the inner yoke 31, and a piston ring 33 a made of a resin sliding material is provided on the piston 33. Further, a permanent magnet 32 that is magnetized in the same manner in two portions and a rider ring 31a made of a resin sliding material are bonded to the outer peripheral side of the inner yoke 31 in the same manner as the inner yoke 11 in FIG. In this way, the movable body 30 includes the internal yoke 31 provided with the rider ring 31a, the permanent magnet 32, and the piston 33 provided with the piston ring 33a.

  A compression space 15 is formed between the piston 33 and the cylinder portion 1 on the head 3 side, and a buffer space 36 is provided between the cylinder portion 1 on the cap 4 side, the internal yoke 31 of the movable body 30, and the internal stator 34. Is formed.

  If the end face of the internal stator 34 on the piston 33 side is short as shown by the two-dot chain line in FIG. 2 and the movable body 30 does not hit the back surface of the piston 33 even if it moves full stroke, The back space 33b may not be provided.

  Next, the operation and effect of the first embodiment will be described.

  In FIG. 1, when the coil 7 is not energized, the movable body 10 is held by the permanent magnet 12 in the neutral position shown in the figure. When a current is passed through the coil 7, a magnetic flux with a thick line shown in the figure is generated, and the movable body 10 moves in the direction of arrow A. When the current flow direction is reversed, the direction of the magnetic flux is also changed, and moves in the direction opposite to the arrow A. That is, when an alternating current is applied to the coil 7, the movable body 10 reciprocates, and helium is compressed and expanded in the compression space 15. The refrigeration generator 18 generates refrigeration by repeating the reciprocating flow.

  The movable body 10 has a vibration system composed of a gas spring generated by compression and expansion of helium in the compression space 15, a gas spring generated by compression and expansion of helium in the buffer space 16, and a magnetic spring of the permanent magnet 12. Formed and has a unique resonant frequency.

  As in the linear compressor 20 of FIG. 1, when the AC current is supplied to the coil 7, the movable body 30 reciprocates and the refrigeration generator 18 of the regenerator type refrigerator 40a generates refrigeration in the linear compressor 40 of FIG. To do. The movable body 30 also forms a vibration system by a synthetic spring obtained by synthesizing the gas spring generated in the compression space 15, the gas spring generated in the buffer space 36, and the magnetic spring of the permanent magnet 32, and has a specific resonance frequency.

  When both linear compressors 20 and 40 are operated in the vicinity of the resonance frequency, the strokes of the movable bodies 10 and 30 are increased, the compression efficiency is increased, and when the mass of the movable bodies 10 and 30 is changed, the linear compressors 20 and 40 The resonance frequency varies.

  The operating frequency for increasing the refrigeration efficiency of the refrigeration generator 18 of the regenerators 20a and 40a does not necessarily match the resonance frequency for increasing the efficiency of the linear compressors 20 and 40. When the resonance frequency of the linear compressors 20 and 40 is matched with the operation frequency of the refrigerator that can obtain high refrigeration efficiency, the power consumption of the linear compressors 20 and 40 is small, and the amount of refrigeration generated by the refrigeration generator 18 of the regenerators 20a and 40a increases. .

  Therefore, when the operating frequency for increasing the refrigeration efficiency of the regenerative refrigerator 20a is lower than the resonance frequency of the linear compressor 20, the adjustment member 14 of the movable body 10 is disposed or the mass of the adjustment member 14 is increased. Thus, the mass of the movable body 10 can be increased, the resonance frequency of the movable body 10 is lowered, and the resonance frequency matches the operating frequency for increasing the refrigeration efficiency of the regenerator chiller 20a, and the compression efficiency of the linear compressor is increased. Get higher.

  When the operating frequency for increasing the refrigerating efficiency of the regenerator 20a is higher than the resonance frequency of the linear compressor 20, the mass of the adjusting member 14 is reduced in the movable body 10, the adjusting member 14 is removed, or By arranging a space on the back surface of the piston 53 to reduce the mass of the piston 53, the mass of the movable body 10 can be reduced, the resonance frequency of the movable body 10 is increased, and the resonance frequency is reduced by the freezing of the regenerative refrigerator 20a. While matching the operating frequency to increase the efficiency, the compression efficiency of the linear compressor is increased.

  As described above, the mass of the movable body 10 can be adjusted so that the resonance frequency of the linear compressor 20 matches the frequency at which the refrigerating efficiency of the regenerator refrigerator 20a is increased, and the operating frequency at which high refrigerating efficiency of the regenerator refrigerator 20a is obtained. Thus, the linear compressor 20 for a regenerative refrigerator that is driven with high efficiency is provided.

  In addition, when the operating frequency for increasing the refrigerating efficiency of the regenerator 40a is higher than the resonance frequency of the linear compressor 40, the magnetic material fixed to the cylinder portion 1 with respect to the hole 31b provided in the internal yoke 31 is used. The internal stator 34 is inserted so as to be able to reciprocate with a small gap. Therefore, by inserting, the mass of the movable body 30 is reduced by the mass of the hole 31b provided in the inner yoke 31, and the resonance frequency of the linear compressor 40 is higher than that in the case where the hole 31b is not provided in the inner yoke 31, The resonance frequency can be adjusted to the operating frequency that increases the refrigeration efficiency of the regenerator type refrigerator 40a. Accordingly, it is possible to provide the linear compressor 40 for a regenerative refrigerator that is driven with high efficiency at an operation frequency at which high refrigerating efficiency of the regenerative refrigerator 40a is obtained.

  As shown in FIG. 2, a space 33 b may be provided on the back surface of the piston 33 to reduce the mass of the movable body 30 and adjust the resonance frequency of the linear compressor 40.

  From the viewpoint of the magnetic circuit, the outer yoke 8, the inner yoke 11 (FIG. 1), 31 (FIG. 2), the outer yoke 8, and the permanent magnets 12 (FIG. 1), 32 (FIG. 2) are the cylinder 2 and A magnetic circuit is formed through the gaps between the cylinder 2 and the movable body 10 (FIG. 2) and 30 (FIG. 3), and the cylinder 2 of the cylinder portion 1 is made thin. 2 and the movable body 10 (FIG. 1) and 30 (FIG. 2) by reducing the respective gaps, the magnetic gap G1 (FIGS. 1 and 2) between the outer yoke 8 and the inner yokes 11 and 31, respectively. The magnetic gap G1 (FIGS. 1 and 2) between the outer yoke 8 and the permanent magnets 12 and 32 is small, and the magnetic gap G1 is smaller than the magnetic gap generated by the coil arrangement of the conventional coil movable linear motor. Further, since the internal stator 34 is a magnetic material, the magnetic flux of the linear motor 35 passes through the gap between the internal yoke 31 and the internal stator 34 and the internal stator 34, and the magnetic flux is hardly saturated. Since the gap between the inner yoke 31 and the inner stator 34 is very small and the magnetic resistance due to the magnetic gap G2 (FIG. 2) based on this gap is small, the magnetic resistance of the magnetic circuit in this case is such that the hole 31b is formed in the inner stator 34. There is almost the same as not. Therefore, in both cases where the internal stator 34 has no hole 31b and the hole 31b, the magnetic resistance of the magnetic circuit is smaller than that of the conventional coil movable linear motor, and the efficiency of the linear motors 5 and 35 is improved. Is higher than the prior art.

  Further, since the permanent magnets 12 and 32 are arranged on the movable bodies 10 and 30 inside the cylinder portion 1, the linear motors 5 and 35 are reduced in size.

  Since at least one of the adjustment member 14 and the pistons 13 and 33 is a non-magnetic material, at least one of the adjustment member 14 and the pistons 13 and 3 hardly flows magnetic flux, and wasteful magnetic flux leakage is reduced. The efficiency of the linear compressors 20 and 40 for the type refrigerator is increased.

  The pistons 13 and 33 are provided with piston rings 13a and 33a to seal the gas, but the piston rings 13a and 33a are not provided, and a ring (not shown) of a resin sliding member is bonded to the pistons 13 and 33. The gas may be sealed by a clearance seal method in which the gap between the outer peripheral surface of the ring and the inner peripheral surface of the cylinder 2 is made minute. In this case, the rider rings 11a and 31a provided on the piston side of the inner yokes 11 and 31 may not be provided.

  Further, the end portions of the movable bodies 10 and 30 on the buffer spaces 16 and 36 side are supported by a leaf spring (not shown) fixed to the cylinder portion 1 so that the movable bodies 10 and 30 and the cylinder 2 are concentric. Also good. In this case, the above-described combined spring is a combination of a leaf spring, a leaf spring, a gas spring in the compression space 15, a gas spring in the buffer spaces 16 and 36, and a magnetic spring. The movable bodies 10 and 30 may be configured not to provide the rider rings 11a and 31a bonded to the internal yokes 11 and 31 by using a clearance seal as a gas seal and supporting the support with a leaf spring.

(Example 2)
FIG. 3 is a cross-sectional view in which a refrigeration generator is connected to a linear compressor for a regenerative refrigerator according to the present invention, and shows a case where a permanent magnet is provided on an external yoke. In detail, it is a figure which shows the adjustment which adjusts the resonance frequency of a linear compressor to the operating frequency which makes the refrigerating efficiency of a cool storage type refrigerator high.

  4 shows a BB cross section of FIG. 3, and FIG. 5 shows a CC cross section of FIG.

  3 differs from the regenerative refrigerator 20a of FIG. 1 in that the permanent magnets 52a, 52b, 52c, 52d of the linear motor 55 of the linear compressor 60 are provided in the external yoke 58. A configuration different from that shown in FIG. 1 will be described with reference to FIGS. 3, 4, and 5. Parts having the same shape as in FIG. 1 are given the same reference numerals as those in FIG.

  The linear motor 55 includes an external stator 56 inserted into the cylinder 2 and a movable body 50 that circumscribes the cylinder 2 so as to be slidable.

  The external stator 56 has an outer yoke 58 in which a plurality of magnetic steel plates made of a magnetic material having a rectangular outer shape and projecting inward and having teeth portions 58a (FIG. 4) and 58b (FIG. 4) facing each other are laminated. Coils 57a and 57b wound around the teeth 58a and 58b, arc-shaped permanent magnets 52a and 52b provided at the ends of the teeth 58a, and permanent magnets 52c provided at the ends of the teeth 58b, 52d. The outer peripheral surfaces of the permanent magnets 52 a, 52 b, 52 c, 52 d are fixed to the tooth portions 58 a, 58 b with an adhesive or the like, respectively, and the inner peripheral surface is also fixed to the outer peripheral surface of the cylinder 2 with an adhesive or the like. The outer peripheral surfaces of the permanent magnets 52a and 52b are magnetized to S and N poles, respectively, and the inner peripheral surfaces are magnetized to N and S poles, respectively, and the outer peripheral surfaces of the permanent magnets 52c and 52d are respectively N and S poles, and The inner peripheral surface is magnetized to the S pole and the N pole, respectively.

  Stoppers 59 for fixing the position of the external stator 56 are fixed to the outer peripheral surface of the cylinder 2 by spot welding or the like at both ends on the inner peripheral side in the axial direction of the external stator 56.

  The movable body 50 includes a columnar inner yoke 51 made of a magnetic material, a piston 53 made of a nonmagnetic material fixedly fitted to convex portions at both ends of the inner yoke 51, and adjustment of a nonmagnetic material that adjusts the mass of the movable body 50. It comprises a member 54, a resin sliding material rider ring 51 a bonded to the outer peripheral surfaces of both ends of the internal yoke 51, and a resin sliding material piston ring 53 a provided on the piston 53. The movable body 50 is inserted between the cylinder 2 and the rider ring 51a with a minute gap (for example, approximately 0.02 mm) so that the inner peripheral surface of the cylinder 2 can slide smoothly.

  FIG. 6 is a cross-sectional view in which a refrigeration generating unit is connected to a linear compressor for a regenerative refrigerator according to the present invention, and shows a case where a permanent magnet is provided on an external yoke. In detail, it is a figure which shows adjustment of the resonant frequency corresponding to the case where the operating frequency which makes the refrigerating efficiency of a cool storage type refrigerator high is higher than the resonant frequency of a linear compressor.

  7 shows the DD cross section of FIG. 6, and FIG. 8 shows the EE cross section of FIG.

  6 differs from the regenerative refrigerator 60a of FIG. 3 in that the structure of the movable body 70 of the linear motor 65 of the linear compressor 60 is different and an internal stator 74 is newly provided. That is. A configuration different from FIG. 3 will be described with reference to FIGS. 6, 7, and 8. Parts having the same shape as in FIG. 3 are denoted by the same reference numerals as those in FIG.

  The inner yoke 71 made of magnetic material has a through hole 71b fitted and fixed, and an inner stator 74 made of magnetic material is inserted with a small gap (for example, approximately 0.05 mm) from the inner peripheral surface of the hole 71b. The internal stator 74 is fixed to the recess of the cap 4.

  A non-magnetic piston 73 is provided on the convex on one end side of the internal yoke 71, and a piston ring 73a of a resin sliding member is provided on the outer peripheral surface of the piston 73. Further, a lid ring 71a of a resin sliding member is bonded to the outer peripheral side of the inner yoke 71 in the same manner as the inner yoke 11 in FIG. In this way, the movable body 70 includes the internal yoke 71 provided with the rider ring 71a and the piston 73 provided with the piston ring 73a.

  If the end face of the internal stator 74 on the piston 73 side is short as shown by a two-dot chain line in FIG. 6 and the movable body 70 does not hit the back surface of the piston 73 even if it moves full stroke, The back space 73b may not be provided.

  Next, the operation and effect of the second embodiment will be described.

  3-5, at the left end side (BB cross section side) of FIG. 3 of the inner yoke 51 and the permanent magnets 52a, 52c, the direction of the magnetic flux Φi1 generated by the current flowing through the coils 57a, 57b is permanent as shown in FIG. If the direction of the magnetic flux Φm2 of the magnets 52a and 52c is the same, the magnetic flux in the gap on the left end side becomes Φi1 + Φm1 and becomes stronger. On the other hand, on the right end side (CC cross section side) of the internal yoke 51 in FIG. 3 and the permanent magnets 52b and 52d, the direction of the magnetic flux Φi2 generated by the current flowing through the coils 57a and 57b is as shown in FIG. Since the direction is opposite to the direction of the magnetic flux Φm2, the magnetic flux in the gap on the right end side becomes (Φi2-Φm2) and becomes weaker. As a result, the magnetic flux in the gap on the left end side of the inner yoke 51 becomes larger than the magnetic flux in the gap on the right end side, and the movable body 50 moves in the A direction (FIG. 3).

  When the direction of the current flowing through the coils 57a and 57b is reversed, the direction of the magnetic flux Φi1 generated by the current is opposite to that described above, the magnetic flux in the gap on the left end side becomes Φi1-Φm1, and the magnetic flux in the gap on the right end side is weakened. It becomes (Φi2 + Φm2) and becomes stronger. As a result, the magnetic flux in the gap on the left end side of the inner yoke 51 becomes smaller than the magnetic flux in the gap on the right end side, and the movable body 50 moves in the direction opposite to the A direction shown in the figure. That is, by passing an alternating current through the coils 57a and 57b, the magnetic flux in the gap between the right end side and the left end side of the inner yoke 51 is biased, and the inner yoke 51, that is, the movable body 50 reciprocates.

  6 to 8, as in FIGS. 3 to 5, when an alternating current is passed through the coils 57 a and 57 b, the magnetic flux on the left end side (DD cross section side) of the linear motor 65 becomes (current current) as shown in FIG. 7. As shown in FIG. 8, the magnetic flux on the right end side (EE cross-section side) is (magnetic flux Φi4 due to current-magnetic flux Φm4 due to permanent magnets 52b, 52d). When the direction of the current is changed, the magnetic flux in the gap on the left end side becomes (Φi3−magnetic flux Φm3), the magnetic flux in the gap on the right end side becomes (Φi4 + Φm4), and the magnetic flux in the gap on the right end side and the left end side of the internal yoke 71 is biased. As a result, the inner yoke 71, that is, the movable body 70 reciprocates.

  6 is different from FIG. 3 in that the magnetic flux flowing through the internal yoke 71 flows through the magnetic gap G2 between the internal yoke 71 and the internal fixing 74 and through the internal fixing 74. FIG. That is, in the case of FIG. 6, there is a magnetic gap G2 between the internal yoke 51 and the internal fixing 74, but in FIG. 3, there is no internal fixing 74, so there is no magnetic gap G2, but the internal yoke 51 and the internal fixing 74 Since the width of the gap between them is very small, the magnetic resistance of the magnetic gap G2 is small and hardly affects the magnetic flux of the magnetic circuit.

  As in the case of FIG. 1 and FIG. 3, the linear compressor 60 of FIG. 3 and the linear compressor 80 of FIG. 6 have helium in the compression space 15 (FIGS. 3 and 6). A gas spring generated by compression and expansion, a gas spring generated by compression and expansion of helium in the buffer space 16 (FIG. 3) and the buffer space 36 (FIG. 6), and magnetic springs of the permanent magnets 52a, 52b, 52, and 52d were synthesized. A vibration system is formed by a synthetic spring, and each has its own resonance frequency. When the masses of the movable bodies 50 and 70 are changed, the resonance frequencies change.

  For the same reason as the cold storage type refrigerator 20a of FIG. 1, the mass of the movable body 50 can be adjusted so that the resonance frequency of the linear compressor 60 matches the operating frequency that increases the refrigeration efficiency of the cold storage type refrigerator 60a. It is possible to provide the linear compressor 60 for a regenerative refrigerator that is driven with high efficiency at an operation frequency at which high refrigeration efficiency of the refrigerator 60a is obtained.

  When the operating frequency for increasing the refrigeration efficiency of the regenerator type refrigerator 60a of FIG. 3 is lower than the resonance frequency of the linear compressor 60, the adjustment member 54 is disposed on the movable body 50, whereby the mass of the movable body 50 is increased. Since it increases, the resonant frequency of the movable body 50 becomes low, and this resonant frequency can be matched with the operation frequency which raises the refrigerating efficiency of the cool storage type refrigerator 60a.

  As in the case of the regenerator type refrigerator 40a of FIG. 2, when the operating frequency for increasing the refrigerating efficiency of the regenerator type refrigerator 80a of FIG. On the other hand, an inner stator 74 made of a magnetic material fixed to the cylinder portion 1 is inserted so as to be able to reciprocate with a minute gap. Accordingly, by inserting, the mass of the movable body 70 is reduced by the mass of the hole 71b provided in the inner yoke 71, and the resonance frequency of the linear compressor 80 becomes higher than the case where the hole 71b is not provided in the inner yoke 71, The resonance frequency can be matched with the operation frequency that increases the refrigeration efficiency of the regenerator chiller 80a. Therefore, it is possible to provide the linear compressor 80 for a regenerative refrigerator that is driven with high efficiency at an operation frequency at which high refrigerating efficiency of the regenerative refrigerator 80a is obtained.

  As shown in FIG. 6, a space 73 b may be provided on the back surface of the piston 73 to reduce the mass of the movable body 70 and adjust the resonance frequency of the linear compressor 80.

  From the point of view of the magnetic circuit, the permanent magnets 52a, 52b, 52c, 52d and the inner yokes 51 (FIG. 3), 71 (FIG. 6) include the cylinder 2 (FIGS. 3, 6) and the cylinder 2 respectively. And a gap between each of the inner yokes 51 and 71, and a magnetic circuit is formed. The thickness of the cylinder 2 of the cylinder portion 1 is reduced, and the gap between each of the cylinder 2 and the inner yokes 51 and 71 is reduced. Is reduced, the magnetic gap G1 (FIGS. 3 and 6) between the outer yoke 8 and the inner yokes 51 and 71 becomes smaller, and the magnetic gap G1 depends on the coil arrangement of the conventional coil movable linear motor. Smaller than the resulting magnetic gap. Further, since the internal stator 74 is a magnetic material, the magnetic flux of the linear motor 65 passes through the gap between the internal yoke 71 and the internal stator 74 and the internal stator 74, and the magnetic flux is hardly saturated. Further, the gap between the inner yoke 31 and the inner stator 34 is very small, and the magnetic resistance due to the magnetic gap G2 based on this gap is small, so that the magnetic flux of the magnetic circuit is hardly affected. Therefore, in both cases where the internal stator 74 does not have the hole 71b and the hole 71b, the magnetic resistance of the magnetic circuit is smaller than that of the prior art coil movable linear motor, and the efficiency of the linear motors 55 and 65 is reduced. The linear motors 55 and 65 for the linear compressor with high efficiency can be provided.

  Further, since the permanent magnets 52a, 52b, 52c, and 52d are disposed on the external stator 6 that is inserted into the cylinder 2, the permanent magnets 52a, 52b, and 52c can be forcibly cooled by a fan (not shown). , 52d can prevent the holding energy from deteriorating due to the temperature rise.

  Since at least one of the adjusting member 54 and the pistons 53 and 73 is a non-magnetic material, at least one of the adjusting member 54 and the pistons 53 and 73 hardly flows magnetic flux, and wasteful leakage magnetic flux is reduced. The efficiency of the linear compressors 60 and 80 for the type refrigerator is increased.

The sectional view which connected the freezing generation part to the linear compressor for the cool storage type refrigerator concerning the present invention shows the case where the permanent magnet is provided in the internal yoke, and shows the resonance frequency of the linear compressor as the freezing efficiency of the cool storage type refrigerator. It is a figure which shows the adjustment match | combined with the driving frequency which raises. The cross-sectional view in which the refrigeration generator is connected to the linear compressor for the regenerator type refrigerator according to the present invention shows a case where a permanent magnet is provided in the internal yoke, and the operating frequency for increasing the refrigerating efficiency of the regenerator type refrigerator is It is a figure which shows adjustment in case it is higher than the resonant frequency of a linear compressor. The sectional view which connected the freezing generating part to the linear compressor for the cool storage type refrigerator concerning the present invention shows the case where the permanent magnet is provided in the external yoke, and shows the resonance frequency of the linear compressor as the freezing efficiency of the cool storage type refrigerator. It is a figure which shows the adjustment match | combined with the driving frequency which raises. Fig. 4 shows a BB cross section of Fig. 3. Fig. 4 shows a CC cross section of Fig. 3. The cross-sectional view in which the refrigeration generator is connected to the linear compressor for the regenerator type refrigerator according to the present invention shows a case where the permanent magnet is provided on the external yoke, and the operating frequency for increasing the refrigerating efficiency of the regenerator type refrigerator is It is a figure which shows adjustment in case it is higher than the resonant frequency of a linear compressor. The DD cross section of FIG. 6 is shown. The EE cross section of FIG. 6 is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder part 2 Cylinder 5, 35, 55, 65 Linear motor 6, 56 External stator 7, 57a, 57b Coil 8, 58 External yoke 10, 30, 50, 70 Movable body 11, 31, 51, 71 Internal yoke 12 , 32, 52a, 52b, 52c, 52d Permanent magnet 13, 33, 53, 73 Piston 14, 54 Adjustment member 15 Compression space 16, 36 Buffer space 18 Refrigeration generator 20, 40, 60, 80 Linear compressor 20a, 40a , 60a, 80a Regenerative refrigerator 31b, 71b Hole

Claims (2)

An external stator having a coil on an external yoke of magnetic material, a movable body that reciprocates with respect to the external stator and having a piston on an internal yoke of magnetic material, and either the internal yoke or the external yoke. A linear motor comprising a permanent magnet;
A cylinder part including a cylinder of a non-magnetic material that is slidably circumscribed by the movable body and is fitted to the inner peripheral surface side of the external stator;
A compression space formed by the cylinder part and the piston;
A linear compressor for a regenerative refrigerating machine having a buffer space formed by the movable body and a cylinder portion opposite to the piston,
The linear compressor is connected to a refrigeration generator of the regenerator type refrigerator,
An adjustment member that makes the resonance frequency of the linear compressor variable is added to the movable body ,
A hole is formed in the internal yoke, and when the regenerative refrigerator operating frequency is higher than the resonance frequency, an internal stator made of a magnetic material fixed to the cylinder portion is removably inserted into the hole. Characteristic linear compressor for regenerative refrigerator The linear compressor for a regenerative refrigerator according to claim 1, wherein at least one of the adjusting member and the piston is a non-magnetic material.

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