JP2008141063A - Magnetic head for magnetization, magnetizer, and medium to be magnetized - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To magnetize a medium to be magnetized with uniform magnetization intensity in a circumferential direction. <P>SOLUTION: A magnetic head 16 for magnetization includes a magnetic core 30 and a coil 60 wound around the core 30. The magnetic core 30 consists of a first yoke 32 and a second yoke 44 which are detachable via mutual screwing. When both yokes 32 and 44 are connected by screwing, a leading end surface (second plane) of a roll 48 formed on the second yoke 44 is closely facing a bottom surface (first plane) of a storage part of the first yoke 32 and forms a magnetic gap. The medium 100 to be magnetized is inserted into a through hole passing through the first and second planes. When power is supplied to the coil 60, a magnetic path extending from the first plane to the second plane is formed symmetrically with the center axis of the through hole as an axis of symmetry. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a magnetization technique for magnetizing a linear magnetized medium.

  For magnetic length measuring devices such as magnetic linear encoders and magnetic linear scales, N poles and S poles are alternately magnetized at a predetermined pitch in the length direction as a scale member indicating the length reference. A magnetized medium having a circular cross section is used. A number of techniques for manufacturing a magnetized medium used in this length measuring instrument, in other words, a technique for alternately magnetizing a magnet with a circular cross-section at a predetermined pitch alternately with a reverse polarity have been proposed (for example, Patent Documents). 1). FIG. 1 is a diagram showing the principle of magnetization in a conventional magnetizing apparatus. In the conventional magnetization technique, magnetization is performed using a magnetic head for magnetization 110 in which a coil 114 is wound around a magnetic core 112 having a magnetic gap 116 formed at the tip thereof. When magnetizing the magnetized medium 100, the magnetized medium 100 is stretched and held, and the magnetic gap 116 portion of the magnetizing magnetic head 110 is brought into contact with the outer peripheral surface of the magnetized medium 100 from the side. . In this state, the magnetizing magnetic head 110 is moved relative to the magnetizing medium 100 by a predetermined pitch in the length direction, and the energization direction to the coil 114 is switched. At this time, the magnetized medium 100 is magnetized to a reverse polarity at a predetermined pitch by a leakage magnetic field leaking from the magnetic gap 116.

Japanese Patent No. 3192311

  Here, as apparent from FIG. 1, in the conventional magnetization technique, a leakage magnetic flux is generated only around one side of the magnetization medium 100. As a result, only one side periphery of the magnetized medium 100 is magnetized. In this case, there are the following problems. As described above, the magnetizing magnetic head 110 is moved relative to the magnetized medium 100 in the length direction during magnetization. At this time, it is often difficult to relatively move the magnetized portion 102 of the magnetized medium 100 while maintaining the straightness of the magnetized portion 102, and the magnetized portion 102 is meandering as shown in FIG. It may become. The magnetized medium 100 meandered and magnetized causes a reduction in accuracy of a length measuring device that uses the magnetized medium 100 as a scale. Further, even if the magnetized portion 102 is magnetized while maintaining straightness, when the magnetized medium 100 is assembled to the length measuring device, the magnetized portion 102 is twisted or twisted. It was necessary to be careful, and this was a cause of complicating the production of measuring instruments and the like.

  Therefore, in the present invention, a magnetizing device capable of uniformly magnetizing the magnetized medium in the circumferential direction, a magnetic head used in the magnetizing device, and a magnetized medium magnetized uniformly in the circumferential direction The purpose is to provide.

  A magnetizing magnetic head according to the present invention is a magnetizing magnetic head for a magnetizing device that magnetizes a linear magnetizing medium, and includes a magnetic core made of a magnetic material, and a portion wound around the magnetic core. The magnetic core includes a first surface and a second surface that form a magnetic gap in close proximity to each other, and a through-hole that passes through the first surface and the second surface, And a main body that forms a magnetic path from the first surface to the second surface, or from the second surface to the first surface, symmetrically about the central axis of the through-hole. It is characterized by that.

  In a preferred aspect, the main body portion is a hollow columnar member in which a winding portion around which a coil is wound is formed to protrude, and the second surface and the first surface are the tip surface of the winding portion and It is the said hollow inner surface facing the said front end surface. At this time, it is desirable that the winding portion is formed with a taper inclined toward the tip.

  In another preferred aspect, the main body portion includes a first yoke having a first surface and a second yoke having a second surface, and the first yoke and the second yoke penetrate the first yoke and the second yoke. Adjustment means is provided for adjusting the gap length, which is the distance between the first surface and the second surface, by relatively moving in the direction of the central axis of the hole. At this time, it is also desirable to have a spacer having a thickness corresponding to a desired gap length, which is disposed between the first surface and the second surface and regulates the gap length. Further, at this time, the second yoke includes a base portion and a winding portion formed so as to protrude from the bottom surface of the base portion. The first yoke has the base portion inserted therein and the bottom surface of the first yoke. It is also desirable that it is a substantially columnar member provided with a recess that functions as a surface. When the magnetized medium has a circular cross section, the adjusting means includes a male screw formed on the outer surface of the base portion and a female screw formed on the inner surface of the recess and screwed into the male screw. It is desirable. When the magnetized medium has a non-circular cross section, it is desirable that the adjusting means has an interference fit structure of the base portion and the concave portion.

  Another magnetizing apparatus according to the present invention includes a medium holding unit that stretches and holds a magnetized medium, a magnetic core in which a through-hole through which the magnetized medium is inserted, and a magnetic core wound around the magnetic core. A magnetizing magnetic head comprising a coil, and a moving means for relatively linearly moving the magnetizing magnetic head along the magnetized medium in a state in which the magnetized medium is inserted through the through hole, A head drive circuit for energizing the coil in conjunction with the relative advance and retreat of the magnetic head, and the magnetic core is a first surface and a second surface that form a magnetic gap in close proximity to each other, A magnetic path from the first surface to the second surface or from the second surface to the first surface is formed symmetrically with respect to the first surface and the second surface through which the through hole passes and the central axis of the through hole as a symmetry axis. And a main body portion.

  Another magnetized medium according to the present invention is characterized in that magnetism is reversed at a predetermined pitch in the length direction and magnetized with a substantially uniform magnetization intensity in the circumferential direction. In this case, the magnetizing medium is inserted into the through hole formed in the magnetic core of the magnetizing head, energizes the coil of the magnetic head, and the magnetizing medium is applied to the magnetic head. It is desirable to be magnetized by relatively reciprocating linearly.

  According to the present invention, the magnetized medium can be magnetized with a uniform magnetization intensity in the circumferential direction by the leakage magnetic field generated symmetrically about the central axis of the through hole through which the magnetized medium is inserted.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 is a schematic top view (FIG. 3A) and a schematic side view (FIG. 3B) of the magnetizing apparatus 10 according to the embodiment of the present invention. The magnetizing device 10 is a device that magnetizes a wire-shaped magnetized medium 100 by reversing the magnetism at a predetermined pitch. The magnetized medium 100 in this embodiment has a circular cross section and is made of a magnetic material such as Fe—Co—Cr.

  The magnetizing device 10 is provided with a pair of holding members 14 a and 14 b that hold both ends of the magnetized medium 100. The pair of holding members 14a and 14b stretch and hold the magnetized medium 100 while maintaining an appropriate tension. Here, the specific configuration of the holding members 14a and 14b is not particularly limited, but in the present embodiment, arc-shaped grooves (not shown) having substantially the same diameter as the magnetized medium 100 are formed on the upper surfaces of the holding members 14a and 14b. The magnetized medium 100 is held by fitting the magnetized medium 100 into the arc-shaped groove.

  The stretched magnetizing medium 100 is magnetized by the magnetizing magnetic head 16. The magnetizing magnetic head 16 is a member composed of a magnetic core and a coil wound around the magnetic core (both not shown in FIG. 3). As will be described in detail later, the magnetic head for magnetization 16 of the present embodiment has a through hole through which the magnetized medium 100 is inserted. The magnetized medium 100 is stretched while being inserted through the through hole.

  The magnetizing magnetic head 16 can be moved along the stretched magnetizing medium 100 by a moving mechanism. The moving mechanism of this embodiment uses the motor 18 as a drive source. The motor 18 is controlled by a control unit 28 via a motor drive circuit 26. A lead screw 20 installed in parallel with the stretched magnetic medium 100 is connected to the output shaft of the motor 18. A head support 22 that supports the magnetizing magnetic head 16 is screwed onto the lead screw 20. When the lead screw 20 rotates by driving the motor 18, the head support 22 and the magnetizing magnetic head 16 screwed into the lead screw 20 linearly advance and retract in parallel with the magnetized medium 100. At this time, the moving direction of the head support 22 is guided by guide rails 24 a and 24 b provided on both sides of the lead screw 20 and connected to the head support 22. The moving mechanism described here is only an example, and other configurations may be used as long as the magnetizing magnetic head 16 can be moved back and forth linearly. Further, the magnetized magnetic head 16 may be moved instead of moving the magnetizing magnetic head 16.

  The coil of the magnetizing magnetic head 16 is connected to the head drive circuit 29. The head drive circuit 29 is a circuit for energizing the coil, and its drive is controlled by the control unit 28. At the time of magnetization, the controller 28 instructs the motor drive circuit 26 to linearly move the magnetizing magnetic head 16 and instructs the head drive circuit 29 to reverse the energization direction of the coil at a predetermined pitch. . Thereby, the magnetized medium 100 is magnetized with the magnetism reversed at a predetermined pitch.

  By the way, the quality of the magnetization, for example, the magnetization range and the magnetization intensity greatly influence the configuration of the magnetic head 16 for magnetization. All of the conventional magnetic heads for magnetization were configured to be magnetized by contacting the magnetized medium 100 from the side (see FIG. 1). In this case, the magnetized medium is magnetized only in the vicinity where the magnetizing magnetic head is in contact. As a result, in the conventional magnetic head for magnetization, the magnetization intensity of the magnetized medium is not uniform in the circumferential direction. In this case, it is necessary to consider the distribution of magnetization intensity when handling the magnetized magnetized medium, which is complicated. Further, it is necessary to move the magnetizing magnetic head straight with respect to the magnetized medium during magnetization so that the magnetizing range does not meander in the length direction. However, the elongated magnetized medium is likely to be twisted, and it is often difficult to accurately move the magnetizing magnetic head straight with respect to the magnetized medium. Therefore, in this embodiment, the magnetizing magnetic head 16 having a special configuration is used in order to magnetize with the magnetization intensity in the circumferential direction substantially uniform. The magnetizing magnetic head 16 will be described in detail below.

  FIG. 4 is an exploded perspective view of the magnetic head 16 for magnetization in the present embodiment. 5 and 6 are sectional views of the first yoke 32 and the second yoke 44, respectively, and FIG. 7 is an assembled sectional view of the magnetic head 16 for magnetization.

  The magnetizing magnetic head 16 includes a magnetic core 30 made of a ferromagnetic material and a coil 60 wound around the magnetic core 30. The magnetic core 30 includes a first yoke 32 and a second yoke 44 that are detachable from each other.

  The first yoke 32 is a substantially cylindrical member. In the center of the first yoke 32, an accommodating portion 34, which is a substantially cylindrical recess for accommodating the second yoke 44, is formed. On the side surface of the housing portion 34, a female screw 36 that is screwed with a male screw 56 formed on the outer surface of the second yoke 44 is formed. A spacer housing portion 38 for housing a spacer 70 described later is formed at the center of the bottom surface of the housing portion 34. The spacer accommodating portion 38 is a substantially circular recess, and the depth thereof is substantially the same as the thickness of the spacer 70. A first through hole 40 through which the magnetized medium 100 is inserted is formed in the center of the spacer accommodating portion 38. The first through hole 40 is a round hole having a diameter slightly larger than that of the magnetized medium 100. A conical recess 42 connected to the first through hole 40 is formed on the bottom surface of the first yoke 32 in order to facilitate the insertion of the magnetized medium 100 into the first through hole 40. Further, a part of the outer surface of the first yoke 32 is notched to form a flat surface 43. The flat surface 43 is formed with a screw hole 43a for attaching the magnetic core 30 to a frame (not shown) of the magnetic head 16 for magnetization.

  The second yoke 44 has a shape in which two substantially cylindrical portions having different diameters are concentrically stacked, and a base portion 46 that is a large-diameter cylindrical portion and a small-diameter circle that extends from the bottom surface of the base portion 46. And a winding part 48 which is a columnar part. The base portion 46 is a cylindrical portion having substantially the same diameter as the accommodating portion 34 of the first yoke 32. On the outer surface of the base portion 46, a male screw 56 that is screwed into the female screw 36 formed in the housing portion 34 is formed. Further, on the upper surface of the base portion 46, a grip portion 58 is formed that is a substantially square convex portion for facilitating the gripping of the second yoke 44 and thus for facilitating the screwing operation.

  The winding portion 48 is a columnar portion that extends from the bottom surface of the base portion 46. The winding portion 48 has substantially the same diameter as an inner diameter of a coil bobbin 62 described later, and the coil bobbin 62 around which the coil 60 is wound is fitted when assembled. A taper 48a is formed at the tip of the winding part 48, and the area of the end surface is narrowed. The front end surface 49 of the winding portion 48 and the bottom surface 39 of the accommodating portion 34 of the first yoke 32 function as a second surface 49 and a first surface 39 that form a magnetic gap in close proximity to each other.

  The second yoke 44 includes a second through hole 50 extending from the upper surface of the gripping portion 58 to the bottom surface (second surface 49) of the winding portion 48, and a pair of terminals extending from the top surface of the gripping portion 58 to the bottom surface of the base portion 46. A hole 54 is formed. The second through hole 50 is a round hole through which the magnetized medium 100 is inserted, and its diameter is slightly larger than that of the magnetized medium 100. The second through hole 50 is formed at the center of the second yoke 44. When the first yoke 32 and the second yoke 44 are screwed and connected, the second through hole 50 is positioned coaxially with the first through hole 40 formed in the first yoke 32. Yes. In other words, the first through hole 40 and the second through hole 50 are through holes that pass through the first surface 39 (the bottom surface of the accommodating portion 34) and the second surface 49 (the tip surface of the winding portion 48), It functions as a through hole through which the magnetized medium 100 is inserted. In order to facilitate the insertion of the magnetized medium 100 into the second through hole 50, a substantially frustum-shaped recess 52 connected to the second through hole 50 is formed on the upper surface of the grip portion 58. The terminal hole 54 is a round hole through which a terminal pin 64 described later is inserted. One terminal hole 54 is provided on each side of the second through hole 50. In the present embodiment, the magnetic core 30 is configured by screwing the first yoke 32 and the second yoke 44 together.

  When winding the coil 60 around the magnetic core 30, first, the coil 60 is wound around the coil bobbin 62. As described above, the coil bobbin 62 has an inner diameter that is substantially the same as the outer diameter of the winding portion 48 of the second yoke 44. The coil bobbin 62 around which the coil 60 is wound is fitted into the winding portion 48, whereby the coil 60 is wound around the magnetic core 30.

  Both ends of the coil 60 are connected to terminal pins 64. The terminal pin 64 is a pin made of a conductive material. The terminal pin 64 is inserted into a terminal hole 54 formed in the second yoke 44, and an end portion of the coil 60 wound around the winding portion 48 is connected to one end thereof. At this time, in order to prevent electrical connection between the terminal pin 64 and the magnetic core 30, the terminal pin 64 is covered with an insulating cover 66 made of a cylindrical member made of an insulating material. A stopper ring 68 is attached to the terminal pin 64 inserted through the terminal hole 54 from the upper side to prevent the terminal pin 64 from coming off from the terminal hole 54. The other end of the terminal pin 64 is connected to the head drive circuit 29.

  Here, as described above, the first yoke 32 and the second yoke 44 are connected to each other by screwing. At this time, in order to adjust the gap amount between the first surface 39 of the first yoke 32 and the second surface 49 of the second yoke 44, a spacer 70 is disposed between them. The spacer 70 is a disk-shaped member made of a nonmagnetic material and having a predetermined thickness. In the center of the spacer 70, a passage hole 70a through which the magnetized medium 100 passes is formed. The passage hole 70 a is significantly larger than the magnetized medium 100. In a state where the spacer 70 is disposed in the spacer housing portion 38 formed on the bottom surface of the housing portion 34, the second surface 44 (the bottom surface of the housing portion 34 is formed by screwing the second yoke 44 to the first yoke 32. ) And the second surface 49 (the front end surface of the winding portion 48) is automatically adjusted to the thickness of the spacer 70.

  Next, the assembly flow of the magnetizing magnetic head 16 will be briefly described. When assembling the magnetizing magnetic head 16, first, the coil 60 and the terminal pin 64 are attached to the second yoke 44. That is, the coil bobbin 62 around which the coil 60 is wound is inserted into the winding portion 48 of the second yoke 44 and fitted. Further, the terminal pin 64 covered with the insulating cover 66 is inserted into the terminal hole 54 of the second yoke 44 from below, and the coil 60 is wound around and connected to the tip of the terminal pin 64. Then, a stopper ring 68 is inserted from above the terminal pin 64 to prevent the terminal pin 64 from falling off.

  If the coil 60 and the terminal pin 64 are attached to the second yoke 44, the second yoke 44 is then screwed to the first yoke 32. At this time, the spacer 70 is disposed in advance in the spacer accommodating portion 38 of the first yoke 32. In this state, the base portion 46 of the second yoke 44 that functions as a screw as a whole is screwed into the accommodating portion 34 that functions as a screw hole as a whole. If the screws can be tightened until the front end surface (second surface 49) of the winding portion 48 of the second yoke 44 comes into contact with the spacer 70, the assembling work of the magnetizing magnetic head 16 is completed.

  The screwing operation of the first yoke 32 and the second yoke 44 is desirably performed in a state where a dummy wire having the same diameter as the magnetized medium 100 is inserted into the first through hole 40 and the second through hole 50. That is, when the first yoke 32 and the second yoke 44 are screwed together, the relative positional relationship between the first through hole 40 and the second through hole 50 is shifted due to minute backlash and the like existing on the screw. May occur. In order to prevent such deviation, a single dummy wire is inserted in advance into the first through hole 40 and the second through hole 50 so that the two through holes 40 and 50 are always located on the coaxial line. It is desirable to adjust the position.

  Next, the principle of magnetization by the magnetizing magnetic head 16 will be described. FIG. 8 is a simplified diagram of the magnetic head 16 for magnetization according to the present embodiment, and is an image diagram showing the principle of magnetization. The first yoke 32 and the second yoke 44 are physically connected by screwing to form the magnetic core 30. The magnetic core 30 can be regarded as a hollow cylindrical member in which a winding portion 48 is protruded and a through hole 40 or 50 is formed in the center. In the magnetizing magnetic head 16 having such a magnetic core 30, when the coil 60 wound around the winding portion 48 is energized, the magnetic core 30 is provided with the accommodating portion 34 from the front end surface 49 of the winding portion 48. A magnetic path H that flows toward the bottom surface 39 (or from the bottom surface 39 of the accommodating portion 34 to the front end surface 49 of the winding portion 48) is formed. At this time, the gap between the accommodating portion bottom surface 39 and the winding portion front end surface 49 becomes the magnetic gap G, and the leakage magnetic flux 72 is generated. The leakage magnetic flux 72 is generated symmetrically with the central axis of the through holes 40, 50, in other words, the central axis of the magnetized medium 100 inserted through the through holes 40, 50 as the symmetry axis. The magnetized medium 100 is magnetized with a uniform magnetization intensity in the circumferential direction by the leakage magnetic flux 72 generated symmetrically. FIG. 9 is an image diagram of the magnetized medium 100 magnetized by the magnetizing magnetic head 16 of the present embodiment. In FIG. 9, the magnetized range is illustrated by sand. As can be seen from FIG. 9, according to the present embodiment, the magnetization medium 100 can be magnetized with uniform strength over the entire circumference. 9 shows a case where the magnetization intensity is shallow, the magnetization range is a donut shape. However, if the magnetization intensity is increased by adjusting the amount of energization to the coil or the like, The entire cross section can be magnetized. Since the film is uniformly magnetized in the circumferential direction in this way, it is not necessary to worry about the twist of the magnetized medium 100, and the magnet can be magnetized very easily. In addition, since the magnetized medium 100 magnetized by the magnetizing magnetic head 16 is magnetized symmetrically with respect to the center line thereof, when the magnetized medium 100 is handled (for example, in a length measuring device). For example, when assembling as a scale portion, it is not necessary to consider the orientation (rotation angle) of the magnetized medium 100, and it can be handled very easily.

  By the way, as already stated, in this embodiment, the 1st through-hole 40 and the 2nd through-hole 50 are made slightly larger diameter than the magnetization medium 100, and the fitting clearance gap has arisen between both. . When this fitting gap is large, the magnetization medium 100 may be eccentric from the through holes 40 and 50, and uniform magnetization in the circumferential direction may be hindered. Therefore, in this embodiment, the fitting gap is set to a size that does not hinder uniform magnetization in the circumferential direction of the magnetized medium 100. Specifically, for example, when magnetizing the magnetized medium 100 having a diameter of 1 mm by reversing the magnetism at a pitch of 0.1 mm, the through holes 40 and 50 have a fitting gap of about 5 to 15 μm. Manage pore size.

  By the way, from the opposite viewpoint, in this embodiment, if the hole diameters of the through holes 40 and 50 are maintained at appropriate values, the relative positional accuracy of the magnetized medium 100 with respect to the leakage magnetic flux 72 is always maintained. Will be. As a result, the magnetization condition (the relative positional accuracy of the magnetized medium 100 with respect to the leakage magnetic flux) hardly changes in the length direction, and the magnet can be magnetized with a uniform magnetization intensity in the length direction. In the conventional magnetizing apparatus, the magnetizing magnetic head 110 is in contact with the magnetizing medium 100 from the side (see FIG. 1). In this case, in order to appropriately control the abutting pressure. Special mechanisms and controls were required. On the other hand, according to the present embodiment, the relative positional accuracy of the magnetized medium 100 with respect to the leakage magnetic flux 72 is automatically managed by the through holes 40 and 50, and therefore, a special for contacting the magnetizing magnetic head 16 Thus, it is not necessary to use a special mechanism or control, and it is possible to magnetize more easily.

  Furthermore, according to the present embodiment, there is an advantage that the distance (gap length L) of the magnetic gap G can be managed very easily. That is, in many conventional magnetic heads for magnetization, a jig is used exclusively for accurately managing the gap length, or the suitability of the gap length is inspected by a special inspection method. On the other hand, in this embodiment, the gap length L is automatically set to a desired value by arranging the spacer 70 having a thickness corresponding to the desired gap length between the winding portion front end surface 49 and the accommodating portion bottom surface 39. Regulated by value. As a result, the manufacturing process of the magnetizing magnetic head 16 can be simplified.

  Further, many of the conventional magnetizing magnetic heads 16 have a fixed gap length L, and when it is desired to magnetize with a different gap length L, it is necessary to prepare a separate magnetizing magnetic head each time. It was. On the other hand, in this embodiment, the gap length L can be easily varied by adjusting the screw tightening amount between the first yoke 32 and the second yoke 44. In other words, in the present embodiment, the female screw 36 of the first yoke 32 and the male screw 56 of the second yoke not only function as connecting means for connecting both, but also as adjusting means for variably adjusting the gap length L. Also works. Moreover, if the thickness of the spacer 70 to be used is changed as appropriate, the gap length L can be easily regulated to a desired thickness. As a result, it is possible to magnetize with various gap lengths L with one magnetizing magnetic head 16.

  Here, in order to perform efficient magnetization, it is required to design the gap depth of the front core portion shallower than the back core portion of the magnetic core. In the present embodiment, the hollow cylindrical portion functions as the back core portion 74, and the periphery of the winding portion 48 functions as the front core portion 76. The diameter of the winding portion 48 that is the front core portion 76 does not depend on the diameter of the hollow cylindrical portion that is the back core portion 74 and can be set freely. Therefore, according to the present embodiment, it is relatively easy to make the gap depth D of the front core portion 76 smaller than the gap depth d of the back core portion 74. As a result, according to the present embodiment, more efficient magnetization is possible.

  Furthermore, in this embodiment, the taper 48a is formed in the winding part front end surface 49, and the opposing area of the magnetic gap G is made small. Thereby, the magnetic resistance in the magnetic gap G increases, and a stronger leakage magnetic flux 72 can be generated. As a result, magnetization with higher efficiency is possible.

  As is clear from the above description, according to the present embodiment, it is possible to uniformly magnetize the magnetized medium 100 in the circumferential direction, and the magnetizing operation can be simplified. Moreover, handling of the magnetized medium 100 after magnetization can be facilitated. Further, since the gap length L can be varied easily and with high accuracy, the magnetization with the optimum gap length can be performed more easily and at low cost. Furthermore, since the gap depth of the front core portion can be reduced as compared with the back core portion, the magnetic efficiency can be increased, and magnetization with higher efficiency becomes possible.

  In the present embodiment, a wire-like member having a circular cross section is described as an example of the magnetizing medium. However, other shapes of wire-like members may naturally be handled as the magnetizing medium. For example, the magnetized medium 100 may be a wire-like member having an elliptical cross section or a rectangular cross section. In this case, what is necessary is just to change the shape of the through-hole formed in a magnetic core and the whole magnetic core according to the cross-sectional shape of the magnetization medium 100. FIG. In addition, when the first yoke and the second yoke are not a cylinder but an elliptical column or a quadrangular column, screwing cannot be selected as a connection unit, but in this case, other connection units such as an interference fit may be used. Should be adopted.

It is the schematic which shows the mode of the conventional magnetization. It is an image figure which shows the magnetization medium magnetized by meandering. It is the schematic top view and schematic side view of the magnetizing apparatus which are embodiment of this invention. It is a disassembled perspective view of the magnetic head for magnetization. It is sectional drawing of a 1st yoke. It is sectional drawing of a 2nd yoke. It is an assembly sectional view of a magnetic head for magnetization. It is an image figure which shows the principle of the magnetization in this embodiment. It is an image figure of the magnetized magnetic medium.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Magnetizing apparatus, 16 Magnetic head for magnetization, 30 Magnetic core, 32 1st yoke, 34 accommodating part, 36 Female screw, 39 1st surface, 40 1st through-hole, 44 2nd yoke, 46 Base part, 48 Winding part, 49 Second surface, 50 Second through hole, 54 Terminal hole, 56 Male screw, 58 Gripping part, 60 Coil, 62 Coil bobbin, 64 Terminal pin, 70 Spacer, 100 Magnetized medium.

Claims (11)

A magnetizing magnetic head for a magnetizing device that magnetizes a linear magnetizing medium,
A magnetic core made of a magnetic material;
A coil wound around a part of the magnetic core;
With
The magnetic core is
A first surface and a second surface forming a magnetic gap in close proximity to each other;
A through-hole passing through the first surface and the second surface, through which the magnetized medium is inserted, and
A main body that forms a magnetic path from the first surface to the second surface, or from the second surface to the first surface, symmetrically about the central axis of the through-hole,
A magnetic head for magnetization characterized by comprising: The magnetic head for magnetization according to claim 1,
The main body part is a hollow columnar member in which a winding part around which a coil is wound is formed to protrude,
The magnetic head for magnetization, wherein the second surface and the first surface are a front end surface of the winding part and the hollow inner side surface facing the front end surface. The magnetic head for magnetization according to claim 2,
The magnetic head for magnetization, wherein the winding portion is formed with a taper inclined toward the tip. The magnetic head for magnetization according to any one of claims 1 to 3,
The main body portion includes a first yoke having a first surface and a second yoke having a second surface,
The first yoke and the second yoke are adjusting means for adjusting the gap length, which is the distance between the first surface and the second surface, by relatively moving the first yoke and the second yoke in the direction of the central axis of the through hole. A magnetic head for magnetization, comprising: The magnetic head for magnetization according to claim 4, further comprising:
A magnetizing magnetic head comprising a spacer having a thickness corresponding to a desired gap length, the spacer being disposed between a first surface and a second surface to regulate the gap length. The magnetic head for magnetization according to claim 4 or 5,
The second yoke includes a base portion, and a winding portion formed to protrude from the bottom surface of the base portion,
The magnetic head for magnetization, wherein the first yoke is a substantially columnar member having the concave portion whose bottom surface functions as the first surface while the base portion is inserted. The magnetic head for magnetization according to claim 6,
If the magnetized medium has a circular cross section,
The adjusting means includes a male screw formed on the outer side surface of the base portion and a female screw formed on the inner side surface of the recess and screwed into the male screw. head. The magnetic head for magnetization according to claim 6,
When the magnetized medium is non-circular in cross section,
The magnetic head for magnetization, wherein the adjusting means has an interference fit structure between the base portion and the concave portion. A magnetizing device for magnetizing a linear magnetized medium,
Medium holding means for holding and holding the magnetized medium;
A magnetic head for magnetization comprising a magnetic core having a through-hole through which a magnetic medium is inserted, and a coil wound around the magnetic core;
Moving means for moving the magnetic head for magnetization relatively linearly along the magnetization medium in a state in which the magnetization medium is inserted through the through hole;
A head drive circuit for energizing the coil in conjunction with the relative advance and retreat of the magnetic head;
With
The magnetic core is
A first surface and a second surface that form a magnetic gap in close proximity to each other, the first surface and the second surface through which the through-hole passes,
A main body that forms a magnetic path from the first surface to the second surface, or from the second surface to the first surface, symmetrically about the central axis of the through-hole;
A magnetizing apparatus comprising: A linear magnetized medium made of a magnetic material,
A magnetized medium, wherein magnetism is reversed at a predetermined pitch in the length direction and magnetized with a substantially uniform magnetization intensity in the circumferential direction. The magnetized medium according to claim 10, wherein
The magnetized medium is inserted into a through hole formed in the magnetic core of the magnetized head according to claim 1 to energize the coil of the magnetic head, and the magnetized medium is relatively straight with respect to the magnetic head. A magnetized medium characterized by being magnetized by advancing and retreating.

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