JPH10336994A - Linear motor and reciprocal compressor employing it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a high efficiency linear motor in which assembling performance and reliability are enhanced by decreasing the number of air gaps and to enhance the total performance and productivity of a reciprocal compressor by applying such a linear motor thereto. SOLUTION: The linear motor comprises an outer core 24 provided with a projecting arm part 21 at an inner intermediate part and core slots 22, 23 on the opposite sides of the projecting arm part 21, first and second coils 25, 26 to be set in the core slots 22, 23 of the outer core 24, a magnet 27 secured to the projecting arm part 21 with a width equal to that of the inner side face of the outer core 24, and a mover, i.e., an inner core 29, reciprocating along the central axis while being supported in the outer core 24 to keep a specified gap between the outer core 24 and the projecting arm part 21. Flux leakage is prevented by arranging such that the flux loop has only a pair of air gaps.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reciprocating compressor (Lin).
ear Compressor)
Motor) and a reciprocating compressor using the linear motor, for example, when a gap through which a loop of magnetic flux passes is one.
A linear motor with high reliability by improving the assemblability by reducing the number of air gaps by improving the efficiency by preventing magnetic flux leakage by having only one piece, and a reciprocating type using the linear motor. It relates to a compressor.

[0002]

2. Description of the Related Art FIG. 6 is a side sectional view showing the structure of a general reciprocating compressor to which a conventional moving magnet type linear motor is applied. The overall configuration of a conventional reciprocating compressor will be described below.
As shown in FIG. 6, a general reciprocating compressor includes a hermetic container 1 having a predetermined shape, a flange (Flange) 2 installed at a predetermined height from the bottom inside the hermetic container 1, and A cylinder 3 installed inside the flange 2, an outer core 4 fixed to the inner peripheral surface of the flange 2, a coil 5 wound inside the outer core 4, and a cylinder (Cyl)
inder) 3 is fixed to the outer peripheral surface of the outer core 4 and the coil 5 so as to maintain a predetermined interval.
ore) 6, a piston spring (Piston Spring) 7 fixedly installed below the flange 2, and a piston holder (Piston Holde) fixed to the center of the piston spring 7.
r) 8 is provided.

A piston 9 fixed to the inner center of the piston holder 8 and reciprocated linearly inside the cylinder 3 and a piston holder 8 fixed to the outer peripheral edge of the piston holder 8 between the outer core 4 and the inner core 6. And a magnet that reciprocates linearly with the piston 9 in the vertical direction
(Magnet) 10 (also referred to as a mover (Mover)) and several mount springs connected and installed between the piston spring 7 and the sealed container 1 to support the piston spring 7.
(Mounting Holder) 11, a valve assembly 12 fixedly installed at an intermediate portion of one side of the flange 2, and a suction-side silencer 13 and a discharge-side silencer 14 installed on both sides of the valve assembly 12.
It is composed of

FIGS. 7 and 8 are views for explaining the operation of the conventional moving magnet type linear motor used in the reciprocating compressor of FIG. The operation of the conventional moving magnet type linear motor will be described below with reference to FIGS. The moving magnet type linear motor applied to the reciprocating compressor shown in FIG. 6 described above is a mover that moves the magnet 10 between the inner core 6 and the outer core 4 as shown in FIGS. This is a structure in which there are two gaps C1 and C2.

[0005] The outer core 4 is radially stacked with reference to the axis of the motor. The inner cores 6 are also radially stacked with respect to the axis center line of the electric motor. The magnet 10 is configured such that the inside and outside have the same polarity with respect to the shaft center line of the motor. 7 and 8, B represents the direction in which the magnetic force acts, and F represents the stress acting on the magnet 10.

In a reciprocating compressor to which a general moving magnet type linear motor is applied, the reciprocating compressor uses a current flowing through a coil 5 and a magnet 10 linearly reciprocating between an outer core 4 and an inner core 6 due to a magnetic flux. By the action and the inertia energy and elastic energy of the piston spring 7, the piston 9 repeatedly performs the operation of sucking and compressing the refrigerant while continuously reciprocating in the vertical direction inside the cylinder 3 and then discharging the refrigerant. Become.

Next, the operation of the linear motor by the current flowing through the coil 5 and the magnetic flux of the magnet 10 will be described in detail. By applying AC power to the coil 5 wound on the outer core 4, the piston holder 8 provided with the magnet 10 reciprocates linearly in the vertical direction. That is, if the current direction of the coil 5 is in the direction in which the current flows, and the magnetic flux direction of the magnet 10 is the axial center direction, A in FIG.
As shown in FIG. 7C, the path of the magnetic flux emerging from the outer core 4 is the gap C1 → the magnet 10 → the gap C2.
→ Inner core 6 → Magnet 10 → Air gap C1 → Outer core 4, the magnet 10 is reluctance (Relucta
nce) moves downward by a small amount.

On the other hand, since the current flowing through the coil 5 is an alternating current, when the direction of the current is changed to the incoming direction, A to A in FIG.
As shown in C, the direction of the magnetic flux flowing through the outer core 4 changes, and the upper side of the reluctance in the magnetic flux direction of the magnet 10 decreases, so that the magnet 10 moves upward. As described above, since the alternating current of the coil 5 flows alternately, the force also acts alternately in the vertical direction, so that the piston holder 8 provided with the magnet 10 reciprocates continuously and linearly, and the linear motor originally has Performs a function.

[0009]

However, the magnetic flux path in the conventional moving magnet type linear motor has a large magnetic flux leakage due to the presence of always two gaps through which the magnetic flux loop passes. There is a disadvantage that the efficiency of the linear motor is reduced. In addition, there are problems that not only the two gaps reduce the assemblability but also the reliability of the linear motor.

Accordingly, the present invention has been made to solve the above-mentioned problems, and the first object of the present invention is to provide a magnetic flux loop.
An object of the present invention is to provide a linear motor capable of realizing high efficiency of a linear motor by preventing a magnetic flux from leaking by providing only one gap through which a loop passes.
A second object of the present invention is to provide a linear motor having improved assemblability due to a reduced number of gaps and improved reliability.

A third object of the present invention is to apply a linear motor manufactured for the above purpose to a reciprocating compressor to improve the overall performance and productivity of the reciprocating compressor. An object of the present invention is to provide a dynamic compressor.

[0012]

SUMMARY OF THE INVENTION The present invention has been made for the purpose of solving the above-mentioned problems, and has, for example, the following constitution in order to achieve the above-mentioned objects. That is,
An outer core having a ridge arm formed at an inner middle portion, and a core slot formed on both sides of the ridge arm; first and second coils respectively wound on both core slots of the outer core; A magnet fixed to the arm tip so as to be substantially flush with the inner surface of the outer core, and supported inside the outer core so that a predetermined gap is maintained between the outer core and the ridge arm. And an inner core that constitutes a mover that reciprocates along an axis center line.

[0013] For example, a linear motor is provided in which first and second coils are wound in the core slots on both sides of the outer core in a direction perpendicular to the laminating direction of the outer core with the center axis of the linear motor as a center. Or,
The first and second coils are wound so that an alternating current flows in the same direction with respect to an axis center line.

A hermetically sealed container having a predetermined shape; a flange installed inside the hermetically sealed container at a predetermined height from a bottom surface and having a cylinder formed therein; and a flange fixed to an inner peripheral surface of the flange. Outer cores each having a core slot formed on both sides of a ridge arm formed at an inner middle portion; first and second cores wound on both core slots of the outer core, respectively;
A coil, a magnet fixed to the ridge arm at the same width as the inner surface of the outer core, a piston spring fixedly installed below the flange, and a piston holder fixed to the center of the piston spring A piston fixed to the center of the inside of the piston holder and reciprocating linearly inside the cylinder, and fixed to the outer peripheral edge of the piston holder such that a predetermined gap is maintained between the outer core and the ridge. An inner core that is a mover that reciprocates in the axial direction, several mount springs that support the piston spring, a valve assembly and a silencer fixedly installed at a predetermined portion of the flange, are included. To provide a reciprocating compressor using a linear motor.

[0015] For example, a linear motor is used in which the first and second coils are wound in the core slots on both sides of the outer core in a direction perpendicular to the laminating direction of the outer core with the axis of the linear motor as the center. Provide a reciprocating compressor. Alternatively, there is provided a reciprocating compressor using a linear motor, wherein the first and second coils are wound so that an alternating current flows in the same direction with respect to a shaft center line.

A magnet 27 having the same polarity on the inside or outside at the center, and polarities different from each other on both sides of the magnet 27 at a predetermined distance apart on both sides so as to be substantially the same as the front end of the magnet 27. And the core slots 22, 23 which are magnetized as described above.
A movable element 29 supported reciprocally between the two core slots while being supported so that a predetermined gap is maintained between the distal end face of the core slot 2 and the distal end face of the magnet 27;
The magnets 2 and 23 are alternately magnetized to have different polarities, so that there is only one gap through which the magnetic flux loop passes, and the mover is magnetized to a different polarity from the magnet 27 with respect to the core slot side. A linear motor characterized by being moved to a position.

Also, a closed container 31 having a predetermined shape,
A flange 32 installed at a predetermined height from a bottom surface inside the closed container 31 and having a cylinder formed therein, and a valve assembly 38 fixedly installed at a predetermined portion of the flange 32
A piston spring 34 fixedly installed below the flange 32; a piston holder 35 fixed to the center of the piston spring 34;
The stator portion 22, 2 of the linear motor
3. A reciprocating motor using a linear motor, wherein the linear motors 3 and 27 are fixed, and the moving element 29 of the linear motor is fixed to the center of the inside of the piston holder 35 to form a piston that linearly reciprocates inside the cylinder. Provide dynamic compressor.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A linear motor according to an embodiment of the present invention and a reciprocating compressor to which the linear motor is applied will be described below in detail with reference to the accompanying drawings. FIG. 1 is a half sectional view showing a main structure of a moving iron type linear motor according to an embodiment of the present invention, and FIG. 5 is a reciprocating apparatus incorporating the linear motor according to the embodiment. It is sectional drawing of a dynamic compressor. The linear motor illustrated in FIG. 1 is formed in a ring shape around the shaft center line 28 as shown in FIG.

First, a linear motor according to the present embodiment will be described with reference to FIG. The linear motor according to the present embodiment has an outer core 24 fixed to a predetermined portion of the motor body.
And a ridge arm formed at an intermediate portion inside the outer core 24.
(Teeth) 21, core slots 22 and 23 on both sides of the ridge arm 21, and a first coil 25 and a second coil 26 wound around each of the core slots 22 and 23. Each is formed.

Further, the linear motor according to this embodiment is
A magnet 27 is fixed to the tip of the ridge arm 21. The magnet 27 is formed in a ring shape around the axis center line 28, and has a structure in which the inside or outside has the same polarity. That is, the polarity of the magnet 27 is configured to be the same on the side surface of the axis center line 28.

Further, the linear motor of this embodiment is
An outer core 24 and a magnet 27 fixed to the tip of the ridge arm portion 21 and an inner core 29 that is a movable member that is supported so as to maintain a predetermined gap C and reciprocates along an axial center line 28. You. The outer core 24 is formed of a ferromagnetic material, and has a shaft center line 2 of a linear motor.
8 and the outer core 2
The ridge arm portion 21 of No. 4 has a structure surrounding the first and second coils 25 and 26 so that the reluctance force can be used more efficiently.

The core slot 2 of the outer coil 24
The first and second coils 25 and 26 are wound on the first and second coils 25 and 26 in a direction perpendicular to the stacking direction of the outer core 24 around the axis center line 28 of the linear motor.
It is configured such that an alternating current in the same direction flows through 26. The inner core 29 is formed of a ferromagnetic material, and is radially laminated with reference to the axis center line 28 of the linear motor, and has a reluctance (reluctance: reluctance).
e) The axial length is formed to be shorter than the axial length of the outer core 24 so that the force is used more efficiently.

The dashed line indicated by reference numeral 30 is the center line of the outer core 24. The linear motor according to the present embodiment having the above-described configuration employs a driving method based on a difference in reluctance (magnetic resistance) with the inner core 29 as a moving element when a magnetic flux flows through the outer core 24. Will be described. 2 and 3 are diagrams for explaining the operation of the moving iron type linear motor according to the present embodiment, FIG. 2 is an operation diagram for explaining a lowered state of the moving element, and FIG. 3 is a moving element. FIG. 9 is an operation diagram for explaining a rising state of the sword.

As shown in FIG. 2A, the current is supplied to the first and second coils 25 and 26 wound on the core slots 22 and 23 of the outer core 24 in the same direction, that is, in the direction in which the current flows. When applied, a magnetic flux is generated in the outer coil 24. At this time, the magnetic path of the magnetic flux becomes as shown in the figure depending on the magnetic pole direction of the magnet 27, and a reluctance difference between the outer core 24 and the inner core 29 is generated. In other words, the center of the magnetic flux emitted from the outer core 24 and the center of the magnetic flux emitted from the magnet 27 are closer to the center line 30 than the center of the magnetic flux entering the outer core 24, so that the inner core 29, which is the moving element, Reluctance moves to the lower side.

As a result, as shown in FIG. 2B, the center of the moving element 29 comes to the center of the outer core 24.
Since the difference in reluctance is small at the lower end, the moving element 29 moves to the lower end at which the reluctance is small.
(C), the reluctance moves to the small lower end. On the other hand, when the moving element 29 reaches the target bottom dead center, if the direction of the current flowing through the first and second coils 25 and 26 is changed to the entering direction, the magnetic flux and the magnetic path as shown in FIG. Also changes direction. As a result, the inner core 29 moves upward due to the reluctance difference between the outer core 24 and the inner core 29.

The operation sequence and principle are the same as when the inner core 29 is lowered. As shown in FIGS. 3B and 3C, the reluctance is small at the upper end side of the outer core 24. Therefore, the inner core 29 moves upward. FIG. 4 is a diagram showing a current and a displacement waveform by an applied voltage of the linear motor according to the present embodiment.

As shown in FIG. 4, when the center position of the moving element is at the center position of the outer core 24, the voltage is input as an AC waveform with the zero point, the top dead center as Dis max, and the bottom dead center as Dis min. When the current is “0”, the displacement of the moving element is at the top dead center and the bottom dead center. That is, when the direction of the current changes, the moving direction of the moving element also changes in the same manner as the above-described operation principle.

FIG. 5 is a side sectional view showing the structure of a reciprocating compressor to which the moving iron type linear motor of this embodiment shown in FIG. 1 is applied. The structure will be described below. The reciprocating compressor to which the moving iron type linear motor of the present embodiment is applied,
An airtight container 31 having a predetermined shape, a flange 32 installed at a predetermined height from the bottom inside the airtight container 31, a cylinder 33 installed inside the flange 32, and fixed to an inner peripheral surface of the flange 32 An outer core 24 having core slots 22 and 23 formed on both sides of a ridge arm portion 21 formed at an inner middle portion, and first and second coils wound around both core slots 22 and 23 of the outer core 24, respectively. 2
5, 26, a magnet 27 fixed to the ridge arm 21 with the same width as the inner surface of the outer core 24, and a flange 32
, A piston holder 35 fixed to the center of the piston spring 34, and a piston 3 fixed to the center of the inside of the piston holder 35 and reciprocating linearly inside the cylinder 33.
6 and the outer core 24 on the outer peripheral edge of the piston holder 35.
And an inner core 2 that is a movable member that is fixed so as to maintain a predetermined gap with the ridge arm portion 21 and reciprocates in the axial direction.
9, several mount springs 37 connected between the piston spring 34 and the sealed container 31 to support the piston spring 34, and a valve assembly 38 fixedly installed at one side intermediate portion of the flange 32. , The suction-side silencer 39 and the discharge-side silencer 4 installed on both sides of the valve assembly 38.
0.

According to the reciprocating compressor of the present embodiment having the above-described structure, by applying the structure of the electric motor unit to the linear motor shown in FIG. Due to the inertia energy and elastic energy of the piston 34, the piston 36
The operation of sucking, compressing, and discharging the refrigerant while continuously reciprocating vertically in the vertical direction in the inside 3 is repeatedly performed, thereby performing the original function of the reciprocating compressor.

[0030]

As described above, according to the present invention, since the magnetic flux loop is configured to have only a pair of gaps, high efficiency of the linear motor is realized by preventing the leakage of the magnetic flux. At the same time, it is possible to provide a linear motor having improved assemblability and reliability by reducing the number of gaps.

Further, by applying the linear motor to a reciprocating compressor, there is an effect of improving the overall performance and productivity of the reciprocating compressor.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing a configuration of a main part of a moving iron type linear motor according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation of the moving iron type linear motor according to the embodiment;

FIG. 3 is a diagram for explaining the operation of the moving iron type linear motor according to the embodiment.

FIG. 4 is a diagram showing current and displacement waveforms according to an applied voltage of the linear motor according to the embodiment.

FIG. 5 is a side sectional view showing the configuration of a reciprocating compressor to which the moving iron type linear motor of the embodiment is applied.

FIG. 6 is a side sectional view showing a configuration of a reciprocating compressor to which a conventional moving magnet type linear motor is applied.

FIG. 7 is a diagram for explaining the operation of a conventional moving magnet type linear motor.

FIG. 8 is a view for explaining the operation of a conventional moving magnet type linear motor.

[Description of Signs] 21 Projecting arm portion 22, 23 Core slot 24 Outer core 25, 26 Coil 27 Magnet 28 Center line of axis 29 Inner core 30 Center line of outer core 31 Sealed container 32 Flange 33 Cylinder 34 Piston spring 35 Piston holder 36 Piston 37 Mount spring 38 Valve assembly 39 Suction silencer 40 Discharge silencer C Gap

Claims (8)

[Claims] 1. An outer core having a ridge arm formed at an inner intermediate portion, core slots formed on both sides of the ridge arm, and first and second coils wound around both core slots of the outer core, respectively. A magnet fixed to the tip of the ridge arm so as to be substantially flush with the inner side surface of the outer core; and a predetermined gap between the outer core and the ridge arm is maintained inside the outer core. And an inner core that constitutes a movable member that is reciprocated along an axis center line. 2. A core slot on both sides of the outer core,
2. The linear motor according to claim 1, wherein the first and second coils are wound around the axis center line of the linear motor in a direction perpendicular to the lamination direction of the outer core. 3. The linear motor according to claim 2, wherein the first and second coils are wound so that an alternating current flows in the same direction with respect to an axis center line. 4. An airtight container having a predetermined shape, a flange installed inside the airtight container at a predetermined height from a bottom surface and having a cylinder formed therein, and fixed to an inner peripheral surface of the flange. Outer cores each having a core slot formed on both sides of a ridge arm formed at an inner intermediate portion; first and second coils respectively wound on both core slots of the outer core; A magnet fixed at the same width as the inner surface, a piston spring fixedly installed below the flange, a piston holder fixed to a central portion of the piston spring, and fixed to an inner central portion of the piston holder And a piston reciprocating linearly inside the cylinder, and fixed to the outer peripheral edge of the piston holder so as to maintain a predetermined gap with the outer core and the ridge. An inner core, which is a movable element that reciprocates in the axial direction, a plurality of mount springs for supporting the piston spring, a valve assembly and a muffler fixedly installed at a predetermined portion of the flange. A reciprocating compressor using a linear motor. 5. The linear motor according to claim 4, wherein the first and second coils are wound in the core slots on both sides of the outer core in a direction perpendicular to the laminating direction of the outer core with respect to a center axis of the linear motor. A reciprocating compressor using a motor. 6. The reciprocating type using a linear motor according to claim 5, wherein the first and second coils are wound so that an alternating current flows in the same direction with respect to an axis center line. Compressor. 7. A magnet 27 having the same polarity on the inside or outside at the center, and polarities different from each other on both sides of the magnet 27 at predetermined positions on both sides of the magnet 27 so as to be substantially the same as the front end of the magnet 27. Slots 22, 23 that are magnetized as follows
A movable element 29 supported so that a predetermined gap is maintained between the end faces of the core slots 22 and 23 and the end face of the magnet 27 and reciprocating between the two core slots; The magnets 23 are alternately magnetized to have different polarities, so that only one air gap through which the magnetic flux loop passes is used to move the movable element to the magnet 27.
A linear motor characterized by being moved to the side of a core slot magnetized with a different polarity from that of the linear motor. 8. A sealed container 31 having a predetermined shape, a flange 32 provided at a predetermined height from the bottom inside the closed container 31 and having a cylinder formed therein, and a predetermined portion of the flange 32 A fixedly installed valve assembly 38, a piston spring 34 fixedly installed below the flange 32, a piston holder 35 fixed to a central portion of the piston spring 34, and an inner peripheral surface of the flange 32. The stator portion 22, 23, 27 of the linear motor according to claim 7 is fixed, and the moving member 29 of the linear motor according to claim 7 is fixed to a central portion inside the piston holder 35, inside the cylinder. A reciprocating compressor using a linear motor, wherein the reciprocating compressor comprises a linearly reciprocating piston.