JP5153806B2 - Galvano scanner - Google Patents

Description

  The present invention relates to a galvano scanner that rotates an optical member to reflect or diffract polarized light.

  A conventional galvano scanner has a stator provided with a coil, a rotor provided with a permanent magnet, and a mirror attached to a rotating shaft of the rotor. Then, the stator is fixed to the housing or the like, the rotor is rotated by receiving the driving torque generated by the coil by the permanent magnet, and the mirror is rotated. While the motor continuously rotates, the galvano scanner rotates within a range of ± tens of degrees from the reference position. The drive current flowing in the coil flows in the opposite direction between when the rotor is rotated (accelerated) and when stopped (decelerated), and has a current waveform similar to a sine wave for smooth operation. When the galvano scanner is applied to laser processing for performing continuous hole processing, acceleration → deceleration → stillation is repeated, and the frequency of the drive current increases when operated at high speed. For this reason, eddy current flows through the permanent magnet, eddy loss occurs, and the temperature of the permanent magnet increases. When the temperature of the permanent magnet is excessively high, thermal demagnetization occurs, the magnet characteristics are deteriorated, and the operation of the galvano scanner is hindered.

  In view of such a situation, there has been proposed a conventional oscillating actuator device in which a groove is formed in a permanent magnet so as to cut off an eddy current path and a temperature increase of the permanent magnet due to eddy loss is suppressed (for example, , See Patent Document 1).

JP 2008-43133 A

  In a conventional oscillating actuator device, a groove is formed in a permanent magnet, and an eddy current path is cut to suppress an increase in temperature of the permanent magnet due to eddy loss. However, forming a groove in the permanent magnet corresponds to a reduction in the axial length of the permanent magnet by the groove width, and there is a problem that the driving torque is reduced. Even if the groove is formed, the eddy current does not completely flow, but flows around the groove. Therefore, when the drive frequency is high, there is a concern that the temperature of the permanent magnet rises beyond the limit.

  Further, in a general motor, a refrigerant is circulated from one side of the rotor in the axial direction to the other side in a gap between the rotor and the stator, thereby suppressing an increase in the temperature of the rotor. However, in the galvano scanner, it is necessary to increase the driving torque in order to operate at high speed, and the gap between the rotor and the stator is narrow. Therefore, even if a rotor cooling method in a general motor is applied, the refrigerant hardly flows through the gap, and the cooling effect is small.

  The present invention has been made in order to solve such a problem, and a galvano scanner capable of suppressing a rise in temperature of a permanent magnet by constructing a refrigerant flow passage with a small pressure loss along the outer peripheral surface of the rotor. The purpose is to obtain.

  A galvano scanner according to the present invention includes a rotor having a shaft and a 2n-pole (where n is a positive integer) permanent magnet disposed around the shaft, and an inner peripheral surface of a cylindrical surface. A stator core disposed so as to surround and a flat frame shape having a pair of long sides, the long sides being parallel to the axial direction of the shaft, arranged in the circumferential direction, on the inner peripheral surface of the stator core A stator having 2n coils fixed to each other and an optical member connected to one end of the shaft in the axial direction are provided, and the optical member is rotationally driven to reflect or diffract polarized light. The suction hole and the discharge hole are formed in the stator core so as to be separated from each other in the axial direction of the shaft and open to the inner peripheral side of at least one of the 2n coils. A refrigerant flow passage that flows to the inner peripheral side of the coil, flows between the inner peripheral surface of the stator core and the outer peripheral surface of the permanent magnet in the axial direction of the shaft to the lower portion of the discharge hole, and flows out from the discharge hole. It is configured.

  According to this invention, the suction hole and the discharge hole are formed in the stator core so as to be separated from each other in the axial direction of the shaft and open to the inner peripheral side of the coil, and the refrigerant flows from the suction hole to the inner peripheral side of the coil. A refrigerant flow passage that flows between the inner peripheral surface of the stator core and the outer peripheral surface of the permanent magnet in the axial direction of the shaft to the lower portion of the discharge hole and flows out of the discharge hole is configured. Therefore, the passage sectional area of the refrigerant flow passage is increased, the pressure loss of the refrigerant flow passage is reduced, the moving speed of the refrigerant can be increased, and high cooling performance can be realized. Thereby, the excessive temperature rise of a permanent magnet is suppressed and the deterioration of the magnet characteristic by the thermal demagnetization of a permanent magnet can be suppressed.

It is a longitudinal cross-sectional view which shows the galvano scanner which concerns on Embodiment 1 of this invention. It is II-II arrow sectional drawing of FIG. It is a side view which shows the principal part of the galvano scanner which concerns on Embodiment 1 of this invention. It is a figure which shows the coil applied to the galvano scanner which concerns on Embodiment 1 of this invention. It is a side view which shows the principal part of the galvano scanner which concerns on Embodiment 2 of this invention. It is a side view which shows the principal part of the galvano scanner which concerns on Embodiment 3 of this invention. It is a side view which shows the principal part of the galvano scanner which concerns on Embodiment 4 of this invention. It is a longitudinal cross-sectional view which shows the galvano scanner which concerns on Embodiment 5 of this invention. It is a longitudinal cross-sectional view which shows the galvano scanner which concerns on Embodiment 6 of this invention. It is XX arrow sectional drawing of FIG. It is XI-XI arrow sectional drawing of FIG.

  Hereinafter, preferred embodiments of the galvano scanner of the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
1 is a longitudinal sectional view showing a galvano scanner according to Embodiment 1 of the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a schematic diagram of the galvano scanner according to Embodiment 1 of the present invention. FIG. 4 is a view showing a coil applied to the galvano scanner according to Embodiment 1 of the present invention, FIG. 4 (a) is a top view, and FIG. 4 (b) is a sectional view. It is. In FIG. 3, the refrigerant intake port, the refrigerant discharge port, and the like are omitted to show the positional relationship between the cooling hole and the coil. Moreover, the pole display of the permanent magnet in FIG. 2 shows the outer peripheral surface.

  1 to 4, the galvano scanner 1 is arranged so that a rotor 5 fixed to a shaft 4 rotatably supported by a housing 2 via a bearing 3 and a rotor 5 fixed to the housing 2 to surround the rotor 5. A stator 7 provided, a galvanometer mirror 10 as an optical member fixed to one end of the shaft 4, an encoder plate 11 fixed to the other end of the shaft 4, a refrigerant suction port 12 for cooling the rotor 5, and And a refrigerant discharge port 13.

  The rotor 5 is configured by mounting a cylindrical permanent magnet 6 coaxially with the shaft 4 in an outer fitting state, and being fixed by an adhesive or the like. The permanent magnet 6 is, for example, a neodymium sintered magnet and is a polar anisotropic magnet that is magnetized and oriented to four poles. Here, since the permanent magnet 6 is a polar anisotropic magnet, the magnetic flux does not leak to the inner diameter side of the permanent magnet 6. Therefore, the shaft 4 does not need to be made of a magnetic material, and can be made of a nonmagnetic material such as SUS304.

  The stator 7 has a stator core 8 formed in a cylindrical body and a coil 9 attached to the stator core 8. The stator core 8 is a dust core produced by, for example, insulating a permalloy powder, press-molding, and heat-treating it. The coil 9 is produced by bending a wire rod such as copper into a flat rectangular frame and bending it into an arc shape in accordance with the inner diameter of the stator core 8. The four rectangular frame-shaped coils 9 are arranged around the inner peripheral surface of the stator core 8 so that a pair of parallel long sides of the rectangular frame shape are parallel to the axial direction of the shaft 4 (hereinafter referred to as the axial direction). It is arranged in the direction and fixed by an adhesive or a mold. The adjacent coils 9 are arranged so as to contact the long sides of the rectangular frame shape. And the adjacent coil 9 is produced by winding a wire rod in the opposite direction, and the flowing direction of the current flowing in the long side of the adjacent rectangular frame shape is the same direction.

The galvanometer mirror 10 is manufactured in a rectangular flat plate shape, and the surface thereof is a reflection surface.
The encoder plate 11 has a slit on the surface, and constitutes a rotary encoder for feedback control of the angular displacement of the galvano mirror 10 in cooperation with a sensor head (not shown). In addition, in order to feedback-control the angular displacement of the galvanometer mirror 10, the rotation angle detection device is not limited to the rotary encoder, and a resolver may be used.

  A square suction hole 14 is formed through the housing 2 and the stator core 8 so as to open to a rectangular frame-shaped inner peripheral side of each coil 9 and a region near one short side. Further, the discharge hole 15 having the same hole shape as the cooling hole 14 passes through the housing 2 and the stator core 8 so as to open to the inner peripheral side of the rectangular frame shape of each coil 9 and the region near the other short side. Is formed. A refrigerant suction port 12 and a refrigerant discharge port 13 are respectively attached to the housing 2 and connected to the suction hole 14 and the discharge hole 15.

  In the galvano scanner 1 configured as described above, the permanent magnet 6 has four poles and the number of coils 9 is four. When the number of poles of the permanent magnet 6 and the number of the coils 9 are the same, and the center of the pole of the permanent magnet 6 is between the adjacent coils 9, the reference position in the rotation direction is set. Then, as indicated by an arrow in FIG. 2, the magnetic flux of the permanent magnet 6 penetrates the coil 9 from the N pole and reaches the stator core 8, flows through the stator core 8 on both sides in the circumferential direction, penetrates the coil 9, and is adjacent to both sides. A magnetic path that enters the S pole and passes through the permanent magnet 6 and returns to the N pole is formed.

  The refrigerant suction port 12 and the refrigerant discharge port 13 are connected to an external cooling device (not shown). Then, as indicated by arrows in FIG. 1, the refrigerant is supplied from the refrigerant suction port 12 through the suction hole 14 to one side in the axial direction on the inner peripheral side of the coil 9, and the outer peripheral surface of the permanent magnet 6 and the stator core 8. A refrigerant flow passage is formed that flows to the other side in the axial direction between the inner peripheral surface and is discharged from the refrigerant discharge port 13 through the discharge hole 15.

Next, laser processing using the galvano scanner 1 will be described.
The galvano scanner 1 is arranged so that the galvanometer mirror 10 is located in the path of the laser beam of a laser processing machine (not shown). The rotation angle of the galvano mirror 10 is controlled by a control circuit (not shown) based on the output of the rotary encoder using the encoder plate 11. Thereby, the reflection direction of the laser beam is changed, and the incident position of the laser beam on the workpiece is controlled.

First, before the operation, the position of the rotor 5 is initialized and adjusted so that the rotational position of the rotor 5 before the operation is located at the reference position. When a current is passed through the coil 9 in this state, the rotor 5 rotates in a direction according to Fleming's left-hand rule due to the interaction with the magnetic flux of the permanent magnet 6. The direction of rotation of the rotor 5 can be changed by the direction of current flowing through the coil 9.
Therefore, the current direction is determined by the position information from the rotary encoder, and the rotor 5 is accelerated and rotated. When approaching the stop position, the rotor 5 is decelerated with the current direction being the reverse direction, and stopped at the target position.
The galvano scanner 1 repeats acceleration->deceleration->stop->acceleration->deceleration-> stop ... to open holes one by one while changing the laser beam irradiation position on the workpiece. become.

  Here, if the continuous drilling speed is 4000 (point / sec), the current frequency is 4 kHz. Since the magnetic flux generated by the current reaches the permanent magnet 6, the internal magnetic field of the permanent magnet 6 also changes at 4 kHz, eddy current flows, and the permanent magnet 6 generates heat due to Joule loss. At this time, a refrigerant, for example, air is supplied from the refrigerant suction port 12 to one end side in the axial direction on the inner peripheral side of the coil 9 through the suction hole 14 and flows between the permanent magnet 6 and the stator core 8 to the other side in the axial direction. The refrigerant is discharged from the refrigerant discharge port 13 through the discharge hole 15. Thereby, the heat generated by the permanent magnet 6 is radiated to the air flowing between the permanent magnet 6 and the stator core 8 in the other axial direction, and the temperature rise of the permanent magnet 6 is suppressed.

Next, for comparison, a description will be given of a case where a rotor cooling method performed by a general motor is applied to the galvano scanner 1.
In this comparative example, the refrigerant flows through the gap between the rotor 5 and the stator 7 from the outer side of the rotor 5 in the axial direction to the other side. However, in the galvano scanner 1, it is necessary to increase the drive torque in order to operate at high speed, and the gap between the rotor 5 and the stator 7, that is, the gap between the permanent magnet 6 and the coil 9 is narrow. Therefore, the passage cross-sectional area of the portion between the permanent magnet 6 and the coil 9 in the refrigerant flow passage is remarkably reduced, and the pressure loss is increased.

  According to the first embodiment, the refrigerant enters from the refrigerant suction port 12 through the suction hole 14 to one end side in the axial direction of the inner periphery of the coil 9, and between the permanent magnet 6 and the stator core 8 to the other side in the axial direction. A refrigerant passage is constructed that flows from the refrigerant discharge port 13 through the discharge hole 15 from the other axial end of the inner periphery of the coil 9. The radial width of the refrigerant flow passage along the surface of the permanent magnet 6 is the sum of the gap between the coil 9 and the permanent magnet 6 and the radial thickness of the coil 9, and the passage cross-sectional area increases. Thereby, the pressure loss of the refrigerant flow passage is reduced, the moving speed of the refrigerant can be increased, and high cooling performance can be realized. Therefore, an excessive temperature rise of the permanent magnet 6 can be suppressed, and deterioration of the magnet characteristics due to thermal demagnetization of the permanent magnet 6 can be suppressed.

In the first embodiment, the coils are arranged in the circumferential direction so that the long sides of the rectangular frame shape are in contact with each other. However, the coil has a minute gap between adjacent long sides of the rectangular frame shape. And may be arranged in the circumferential direction.
In the first embodiment, the stator core is formed in a cylindrical body. However, the stator core only needs to have a cylindrical inner surface, and the outer peripheral surface does not have to be a cylindrical surface. .

Embodiment 2. FIG.
FIG. 5 is a side view showing a main part of a galvano scanner according to Embodiment 2 of the present invention. In FIG. 5, the refrigerant suction port, the refrigerant discharge port, and the like are omitted to show the positional relationship between the cooling hole and the coil.

In FIG. 5, in the housing 2 and the stator core 8, the long hole-shaped suction hole 16 and the discharge hole 17 are opened in regions near the inner peripheral edge portions of both short sides of the rectangular frame of each coil 9. The long hole is formed so that the long axis of the long hole coincides with the rotation direction of the rotor 5.
Other configurations are the same as those in the first embodiment.

  Also in the second embodiment, the refrigerant passes from the refrigerant suction port 12 through the suction hole 16 to one end side in the axial direction of the inner periphery of the coil 9 and flows between the permanent magnet 6 and the stator core 8 in the other axial direction. A refrigerant passage that is discharged from the refrigerant discharge port 13 through the discharge hole 17 from the other axial end side of the inner periphery of the coil 9 is constructed. Therefore, in the second embodiment, as in the first embodiment, an excessive temperature rise of the permanent magnet 6 can be suppressed, and deterioration of the magnet characteristics due to thermal demagnetization of the permanent magnet 6 can be suppressed.

  The magnetic flux of the permanent magnet 6 penetrates the coil 9 from the N pole and reaches the stator core 8, flows in the stator core 8 on both sides in the circumferential direction, penetrates the coil 9, enters the adjacent S pole, passes through the permanent magnet 6, and passes through the permanent magnet 6. Return to North Pole. Here, since the magnetic flux of the permanent magnet 8 that has entered the stator core 8 flows in the rotation direction of the rotor 5 in the stator core 8, the cross-sectional area of the magnetic path decreases as the axial length of the suction hole and the discharge hole increases. . For this reason, in the case of a high magnetic flux density design, this magnetic flux density reaches a saturation magnetic flux, resulting in a decrease in torque characteristics.

According to the second embodiment, the suction hole 16 and the discharge hole 17 are formed in a long hole shape with the rotation direction of the rotor 5 as the long axis. Therefore, when the cross-sectional areas of the suction hole 16 and the discharge hole 17 are equal to the cross-sectional areas of the suction hole 14 and the discharge hole 15 in the first embodiment, the short axis lengths of the suction hole 16 and the discharge hole 17, that is, The axial length is shorter than the suction hole 14 and the discharge hole 15. As a result, a decrease in magnetic path cross-sectional area due to the formation of the suction hole 16 and the discharge hole 17 can be suppressed, so that the torque characteristics can be improved while maintaining the cooling performance.
Further, when the axial lengths of the suction hole 16 and the discharge hole 17 are made equal to the axial lengths of the suction hole 14 and the discharge hole 15, the long axial lengths of the suction hole 16 and the discharge hole 17, that is, the circumferential lengths thereof. The length is longer than that of the suction hole 14 and the discharge hole 15. Thereby, since the cross-sectional areas of the suction hole 16 and the discharge hole 17 are increased, the cooling performance can be enhanced while maintaining the torque characteristics.

Embodiment 3 FIG.
FIG. 6 is a side view showing a main part of a galvano scanner according to Embodiment 3 of the present invention. In FIG. 6, the refrigerant suction port, the refrigerant discharge port, and the like are omitted to show the positional relationship between the cooling hole and the coil.

In FIG. 6, the suction hole 18 and the discharge hole 19 having a circular cross section pass through the housing 2 and the stator core 8 so as to open in areas near the inner peripheral edges of both short sides of the rectangular frame of each coil 9. In addition, three are formed in a row in the rotational direction of the rotor 5.
Other configurations are the same as those in the first embodiment.

  Also in the third embodiment, the refrigerant enters from the refrigerant suction port 12 through the suction hole 18 to one end side in the axial direction of the inner periphery of the coil 9 and flows between the permanent magnet 6 and the stator core 8 to the other side in the axial direction. A refrigerant passage that is discharged from the refrigerant discharge port 13 through the discharge hole 19 from the other axial end of the inner periphery of the coil 9 is constructed. Therefore, in the third embodiment, as in the first embodiment, an excessive temperature rise of the permanent magnet 6 can be suppressed, and deterioration of the magnet characteristics due to thermal demagnetization of the permanent magnet 6 can be suppressed.

According to the third embodiment, three suction holes 18 and three discharge holes 19 are formed in a row in the rotational direction of the rotor 5. Therefore, when the cross-sectional areas of the suction hole 18 and the discharge hole 19 are equal to the cross-sectional areas of the suction hole 14 and the discharge hole 15 in the first embodiment, the axial lengths of the suction hole 18 and the discharge hole 19 are: This is shorter than the axial lengths of the suction hole 14 and the discharge hole 15. As a result, a decrease in the magnetic path cross-sectional area due to the formation of the suction hole 18 and the discharge hole 19 can be suppressed, so that the torque characteristics can be improved while maintaining the cooling performance.
Further, when the axial lengths of the suction hole 18 and the discharge hole 19 are made equal to the axial lengths of the suction hole 14 and the discharge hole 15, the total cross-sectional area of the suction hole 18 and the discharge hole 19 increases. The cooling performance can be enhanced while maintaining.

  According to the third embodiment, since the suction hole 18 and the discharge hole 19 are hole-shaped with a circular cross section, drilling is facilitated.

Embodiment 4 FIG.
FIG. 7 is a side view showing a main part of a galvano scanner according to Embodiment 4 of the present invention. In FIG. 7, the refrigerant suction port, the refrigerant discharge port, and the like are omitted to show the positional relationship between the cooling hole and the coil.

In FIG. 7, the suction hole 20 and the discharge hole 21 are formed so as to penetrate the housing 2 and the stator core 8 so as to open in contact with the inner peripheral edge portions of both short sides of the rectangular frame shape of each coil 9. ing. The suction hole 20 and the discharge hole 21 are formed in a D-shaped hole shape.
Other configurations are the same as those in the first embodiment.

Therefore, the fourth embodiment also has the same effect as the first embodiment.
According to the fourth embodiment, since the suction hole 20 and the discharge hole 21 are formed so as to be in contact with the short side edge of the rectangular frame shape of the coil 9, the axial direction between the suction hole 20 and the discharge hole 21 is formed. The distance gets longer. Therefore, the length of the refrigerant flow path along the surface of the permanent magnet 6 is increased, and the permanent magnet 6 can be effectively cooled.

  In the fourth embodiment, the suction hole 20 and the discharge hole 21 are formed in a D-shaped hole shape, but the hole shape of the cooling hole is not limited to the D-shape, What is necessary is just to adapt to the inner peripheral shape of the axial direction both sides of a coil. For example, if the coil frame shape is rectangular, the hole shape of the cooling hole is rectangular. Further, if the frame shape of the coil is a racetrack shape in which long sides of a rectangle are connected by a semicircle, the hole shape of the cooling hole is a semicircle.

Embodiment 5 FIG.
FIG. 8 is a longitudinal sectional view showing a galvano scanner according to Embodiment 5 of the present invention.

In FIG. 8, the suction hole 14 is formed through the housing 2 and the stator core 8 so as to open in a region near the inner peripheral edge of the other short side of the rectangular frame of each coil 9. Further, the discharge hole 15 is formed through the housing 2 and the stator core 8 so as to open in a region near the inner peripheral edge of one short side of the rectangular frame shape of each coil 9. The refrigerant suction port 12 and the refrigerant discharge port 13 are connected to the suction hole 14 and the discharge hole 15, respectively.
Other configurations are the same as those in the first embodiment.

  In the galvano scanner 1A configured as described above, the refrigerant passes from the refrigerant suction port 12 through the suction hole 14 and enters the other axial end side of the inner periphery of the coil 9, and axially passes between the permanent magnet 6 and the stator core 8. A refrigerant passage that flows to one side and is discharged from the refrigerant discharge port 13 through the discharge hole 15 from one axial end side of the inner periphery of the coil 9 is formed.

  Therefore, since the other axial end of the permanent magnet 6 is preferentially cooled, the heat transmitted from the permanent magnet 6 to the rotary encoder side via the shaft 4 is reduced, and the temperature rise of the rotary encoder is suppressed. As a result, it is possible to use a rotation angle detector with an ultra-high resolution whose operating temperature range is as narrow as 80 ° C. or less.

Embodiment 6 FIG.
9 is a longitudinal sectional view showing a galvano scanner according to Embodiment 6 of the present invention, FIG. 10 is a sectional view taken along the line XX in FIG. 9, and FIG. 11 is a sectional view taken along the line XI-XI in FIG. 10 and 11, the refrigerant suction port, the refrigerant discharge port, and the like are omitted. Further, the arrows in FIGS. 10 and 11 indicate the flow of magnetic flux.

9 to 11, the stator core 8 </ b> A is formed in a cylindrical body, and a radially thick outer wall portion 22 is formed on an axially inner edge of the suction hole 14 and the discharge hole 15 in the axial direction. And the entire width of the suction hole 14 and the discharge hole 15 in the circumferential direction. The stator 7A is formed by arranging four rectangular frame-shaped coils 9 on the inner peripheral surface of the stator core 8A in the circumferential direction so that the long sides of the rectangular frame shape are parallel to the shaft 4 and in contact with each other. It is fixed by an agent or a mold. The stator 7A is fixed to the housing 2A so as to extend the thick portion 22 from the housing 2A, and surrounds the rotor 5.
Other configurations are the same as those in the first embodiment.

  Also in the galvano scanner 1B configured in this way, the refrigerant enters the one end side in the axial direction of the inner periphery of the coil 9 from the refrigerant suction port 12 through the suction hole 14, and axially passes between the permanent magnet 6 and the stator core 8A. A refrigerant passage that flows to the other side and is discharged from the refrigerant discharge port 13 through the discharge hole 15 from the other axial end of the inner periphery of the coil 9 is constructed. Therefore, also in the sixth embodiment, as in the first embodiment, the permanent magnet 6 is effectively cooled and thermal demagnetization of the permanent magnet 6 is suppressed.

  In the galvano scanner 1 </ b> B, the thick portion 22 is formed on the inner edge in the axial direction of the suction hole 14 and the discharge hole 15 over the entire region in which the suction hole 14 and the discharge hole 15 are formed in the circumferential direction. Therefore, the reduction in the cross-sectional area of the stator core 8A in the plane passing through the axis due to the formation of the suction hole 14 and the discharge hole 15 is complemented by the thick portion 22, so that the periphery of the suction hole 14 and the discharge hole 15 Can prevent magnetic saturation and improve torque characteristics.

Here, it is preferable to form the thick portion 22 so that the magnetic path cross-sectional areas in the rotation direction of the stator core 8A are substantially equal in the circumferential direction.
In the sixth embodiment, the thick portion 22 is formed in the axially inner edge of the suction hole 14 and the discharge hole 15 apart from each other in the axial direction. 14 and the discharge hole 15 may extend in the axial direction.

In each of the above embodiments, the stator core is made of a dust core. However, the core may be made of a magnetic material. For example, a laminated core made by laminating and integrating magnetic steel plates may be used.
Further, in each of the above embodiments, the coil is formed in a flat rectangular frame shape, but the shape of the coil is not limited to a flat rectangular frame shape, and a pair of parallel long sides are formed. It may be a flat frame shape having a racetrack shape in which ends of a pair of parallel long sides are connected by a semicircle, for example.

In each of the above embodiments, a polar anisotropic magnet is used as the permanent magnet. However, the permanent magnet is not limited to the polar anisotropic magnet, and a parallel anisotropic magnet or a radial anisotropic magnet is used. Also good. In this case, the shaft needs to be made of a magnetic material.
Moreover, in each said embodiment, although the permanent magnet shall be produced with the neodymium sintered magnet, a permanent magnet does not need to be limited to a neodymium sintered magnet, For example, a samarium type sintered magnet may be sufficient.

In each of the above embodiments, a galvanometer mirror is used as an optical member. However, the optical member is not limited to a galvanometer mirror, and may be a diffraction grating, for example.
In each of the above embodiments, a 4-pole permanent magnet is used. However, the number of poles of the permanent magnet is not limited to 4 and may be 2n (where n is a positive integer). If the number of poles of the permanent magnet is 2n, the number of coils is also 2n.
In each of the above embodiments, the suction hole and the exhaust hole are formed so as to open to the inner peripheral side of each coil. However, the suction hole and the exhaust hole are opened to the inner peripheral side of at least one coil. What is necessary is just to be formed.

  1, 1A, 1B Galvano Scanner, 2, 2A Housing, 4 Shaft, 5 Rotor, 6 Permanent Magnet, 7, 7A Starter, 8, 8A Starter Core, 9 Coil, 10 Galvano Mirror (Optical Member), 11 Encoder Plate (Rotary Encoder, rotation angle detector), 14, 16, 18, 20 Suction hole, 15, 17, 19, 21 Discharge hole, 22 Thick part.

Claims (7)

A rotor having a shaft and a 2n pole (n is a positive integer) permanent magnet disposed around the shaft;
It is manufactured in the shape of a flat frame having a cylindrical inner surface, a stator core disposed so as to surround the rotor, and a pair of long sides, with the long sides parallel to the axial direction of the shaft. A stator having 2n coils aligned in a direction and fixed to the inner peripheral surface of the stator core;
An optical member connected to one axial end of the shaft, and
In the galvano scanner that rotationally drives the optical member to reflect or diffract polarized light,
A suction hole and a discharge hole are formed in the stator core so as to be spaced apart in the axial direction of the shaft and open to an inner peripheral side of at least one of the 2n coils;
The refrigerant flows from the suction hole to the inner peripheral side of the coil, flows between the inner peripheral surface of the stator core and the outer peripheral surface of the permanent magnet in the axial direction of the shaft to the lower part of the discharge hole, and from the discharge hole. A galvano scanner, characterized in that a refrigerant flow passage is formed.   The galvano scanner according to claim 1, wherein the suction hole and the discharge hole have a long hole shape in which a long axis direction is a circumferential direction.   2. The galvano scanner according to claim 1, wherein each of the suction holes and the discharge holes is constituted by a plurality of holes formed in a line in the circumferential direction.   The galvano scanner according to claim 3, wherein a hole shape of the plurality of holes is circular.   5. The stator core according to claim 1, wherein the suction hole and the discharge hole are formed in the stator core so as to be in contact with an inner peripheral edge portion in an axial direction of the shaft of each of the coils. A galvano scanner according to claim 1. A rotation angle detection device is disposed on the other axial side of the shaft,
The said suction hole is located in the axial direction other side of the said shaft, The said discharge hole is located in the axial direction one side of the said shaft, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. Galvo scanner.   7. The stator core according to claim 1, wherein at least a portion between the suction hole and the discharge hole and in contact with the suction hole and the discharge hole is formed thick. The galvano scanner described in.

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