JP5045093B2 - Linear motor and linear motor armature bobbin - Google Patents

Description

  The present invention relates to a linear motor, and more particularly to an armature thereof.

A conventional linear motor is composed of a strip plate body made of a nonmagnetic conductive material, two or more strip plates made of a magnetic material such as iron, and an injection resin. The strip plate body has a width parallel to the surface thereof. Two or more strip-shaped plate insertion holes arranged in parallel in the direction, a large indentation portion for resin injection and a small indentation portion for air vent are formed over the entire length on the side opposite to the surface side of the strip-plate body, Each of the strip plate insertion holes is inserted in the length direction of the strip plate body, and the injected resin is injected between each strip plate insertion hole and the inserted strip plate to fix the strip plate. (For example, see Patent Document 1)

In addition, in a conventional inductance element, a winding core having a circular ridge around which a winding is wound is housed in an outer case, and a casting agent made of a thermosetting resin is injected into the outer case to form the winding core. It is sealed and fixed, and a vertical groove for air venting is provided in parallel with the storage direction at the position of the inner surface of the opening at the corner of the outer case. (For example, see Patent Document 2)

Further, in the conventional chip coil, the coil winding is wound around the core having the flange portions formed at both ends, and the periphery thereof is externally sealed with an insulating resin material, and at least the core side surface of the flange portion has the core A plurality of grooves reaching the outer peripheral edge of the groove are formed. (For example, see Patent Document 3)

Japanese Utility Model Publication No. 6-40406 (FIG. 1) Japanese Patent No. 318691 (FIG. 1) JP-A-2-214107 (FIG. 2)

The armature of a linear motor needs to be made of resin around the coil for the purpose of fixing and insulating the coil. However, since the resin is mixed with air in the process of pouring the liquid resin into the mold, air traps (nests and voids) may be formed. Conventionally, air-growing grooves and holes are inserted in the casting resin instead of the coil itself. However, there is a case where it is provided on a mold on the opposite side of the coil, but there is a problem that the armature including the coil and the injected resin becomes thick. In addition, even when a groove for air venting is provided in the core on the coil side, a recess is provided in the core in order to improve the core moldability by reducing (averaged) the thickness variation of the core. Is easy to trap air when the coil is resin-molded, especially when the recess does not reach the outer edge of the core, and depending on the position of the air vent groove, the effect cannot be obtained sufficiently. There was a case.
Furthermore, if air remains in the resin even if air vents or holes are provided as in the past, for example, the air mixed during casting in a vacuum defoamer may be forcibly removed or left for a while to naturally I was deflated. In particular, when the resin filled on the coil surface is relatively thin (for example, 0.5 mm or less), the efficiency of air removal is poor, and it takes time to fully escape or does not escape completely. There was a case. As a result, the fixing strength and insulation of the coil are lowered, the reliability of the product may be lowered, and the productivity may be lowered and the appearance of the product may occur.

The present invention was made to solve the above-described problems, without increasing the thickness of the armature of the linear motor, without leaving air in the recesses of the resin bobbin in the manufacturing process, In addition, the purpose is to provide a linear motor that suppresses the generation of voids inside and on the surface of the resin, has strong coil fixing strength, good insulation, high productivity, high product reliability, and good product appearance. And

The linear motor according to the present invention includes a stator having a plurality of permanent magnets arranged in parallel to the field yoke so that adjacent polarities are different, and windings on a part of the outer surface of the bobbin. And an armature in which a plurality of coils having recesses formed on the outer surface of the bobbin not fixed to each other are fixed with a resin, and the plurality of coils are arranged to face the magnet row of the permanent magnets. In the linear motor, the bobbin has an air vent groove that partially overlaps with the recess, is mixed when the coil is fixed with resin, and extends to the outer edge of the bobbin in a direction in which air staying in the recess is released. is there. Thereby, the air in the resin can be efficiently removed, and the generation of voids in the armature of the linear motor can be suppressed.

In the linear motor, a plurality of the air vent grooves are provided on one side or both sides of the bobbin. Thereby, the air in the resin can be extracted more efficiently, and the generation of voids in the armature of the linear motor can be suppressed.

  According to the present invention, without increasing the thickness of the armature of the linear motor, the generation of voids in the resin and the surface in the manufacturing process is suppressed, the coil fixing strength is strong, the insulation is good, the productivity is high, High product reliability can be secured, and a linear motor with a good product appearance can be obtained.

Embodiment 1 FIG.
Hereinafter, Embodiment 1 of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing the entire armature and a part of the internal state of the linear motor according to the present embodiment. FIG. 2 is a perspective view showing the structure of a single coil constituting the armature. It is. FIG. 3 is a first example showing the shape of a bobbin that is a winding core of a coil, and FIG. 4 is a cross-sectional view of the first example of the bobbin shape. FIG. 5 is a second example showing the shape of the bobbin, and FIG. 6 is a cross-sectional view of the second example of the bobbin shape. FIG. 7 is a perspective view showing the entire casting jig in a state where a coil is provided and a resin is cast and a part of the inside state. FIG. 8 is a cross-sectional view of a casting jig in which a coil is disposed and a resin is cast. FIG. 9 is a perspective view of the entire linear motor of the present embodiment.

The armature of the linear motor according to the present embodiment will be described. In FIG. 1, a plurality of coils 11 are arranged in series to constitute an armature winding portion 10, and the coil 11 is fixed to a metal frame 15 by a resin 14 that is solidified after casting. The metal frame 15 is provided with a resin injection port 16 and an air vent hole 17.

Next, the coil will be described. In FIG. 2, the coil 11 has a structure formed by winding an electric wire around a bobbin 12. The bobbin 12 is a molded product or a processed product made of, for example, a liquid crystal polyester (LCP) resin or a polyether ether ketone (PEEK) resin. The bobbin 12 has an air vent groove 13.

A first example of the bobbin shape will be described. 3 and 4, when the bobbin 12 is manufactured by molding, a recess 32 for stabilizing molding so that the molding resin thickness of the bobbin does not largely change in order to prevent generation of voids during molding. Is provided. In some cases, it may be a hole. Thus, the concave portion 32 provided for averaging the thickness of the resin is often provided inside the outer edge of the bobbin 12. Further, the bobbin 12 is provided with air vent grooves 13 on one side on each side so as to partially overlap the recess 32. Here, the air vent groove 13 may be only on one side. The air vent groove 13 is provided so that the extending direction of the groove is in a vertically upward direction, which is the direction in which air escapes, in the case of resin casting of an armature, which will be described in detail later. It is provided to reach the edge. By providing the air vent groove 13, the air mixed in the resin can be efficiently discharged to the outside during the resin casting of the armature, which will be described later, and the air accumulated in the recess 32 at that time escapes to the outside. Can be secured. In addition, it is preferable that the air vent groove 13 is provided in parallel and in a straight line with respect to the vertical direction when the armature resin is cast, which will be described in detail later. As long as it comes out, the extending direction of the groove may be oblique to the vertical direction or may be curved. The mounting hole 31 is used to determine the mounting position on the casting jig. The protrusion 33 is provided to determine the gap between the coil surface into which the resin flows and the casting jig. As shown in FIG. 8, the protrusion 33 sandwiches the bobbin 12 between the front plate 71 and the back plate 72, and the protrusion 33 and both plates come into contact with each other, so that a gap corresponding to the height of the protrusion 33 is formed. It can be ensured as a gap filling the resin. Accordingly, the protrusion 33 plays a role of ensuring a stable and constant resin thickness even when the height of the protrusion 33 is reduced to narrow the gap for filling the resin (for example, 0.5 mm or less).

Here, as in the second example of the bobbin shape shown in FIGS. 5 and 6, a plurality of air vent grooves 13 may be provided on both sides on one side. A plurality of them may be provided only on one side, one on one side and a plurality on the opposite side.

Next, a casting jig for forming the resin portion of the armature will be described. In FIG. 7, the coil 11 is accurately positioned by inserting a pin 77 provided on the front plate 71 or the back plate 72 of the casting jig into the mounting hole 31 of the bobbin 12. A plurality of coils 11 that are positioned and aligned are connected, and a metal frame 15, a first side plate 73, a second side plate 74, and a bottom plate 76 are attached to the connected coils 11, and the metal frame 15 is held by the upper plate 78. Yes. Mounting screws 75 are used for the first side plate 73 and the second side plate 74. An air vent hole 17 is provided in the metal frame 15 at a position directly above the coil 11. The upper plate 78 is provided with an opening 79 in accordance with the position and size of the resin injection port 16 of the metal frame 15.

The casting jig will be further described with reference to FIG. 8 showing a sectional view of the casting jig and the coil during resin casting. The coil 11 is accurately positioned in the casting jig by inserting the pin 77 of the casting jig into the mounting hole 31 provided in the bobbin 12. The resin 14 fixes and connects the coil 11 and the metal frame 15, and also performs an insulating function of the coil 11. The air mixed in the resin 14 passes through the air vent groove 13 of the bobbin 12 and is released to the outside through the air vent hole 17 formed in the upper metal frame 15.

The state at the time of casting and the function of the air vent groove 13 will be described. In FIG. 7, when casting the resin, the resin is poured from the resin inlet 16 through the opening 79 of the upper plate 78. In FIG. 8, the resin passes through the inside of the metal frame 15 and fills the gap between the coil 11 and the casting jig. The resin thickness of the coil surface is determined by the height of the protrusion 33 provided on the bobbin 12, thereby accurately forming a resin thickness having a constant thickness. When the resin is filled, the casting operation is stopped. After that, if the resin is a thermosetting resin, it is heated and cured at a constant temperature in a thermostatic bath for a certain period of time. Force out the mixed air. After performing this air venting operation, if the casting jig is left alone, the remaining air is gradually removed through the flow path corresponding to the thickness of the resin filled with the resin, but the resin filled on the coil surface is relatively thin. Even in the case (for example, 0.5 mm or less), by providing the air vent groove 13 in the bobbin 12, the air can be easily removed from here, and the time required to remove the air is shortened, and the resin surface void of the armature is reduced. It becomes possible to make it. Further, the air remaining without being completely removed from the recess 32 of the bobbin 12 can be efficiently discharged outside through the air release groove 13 by providing the air release groove 13 partially overlapping the recess 32.

A linear motor using the armature as a mover will be described. In FIG. 9, the linear motor is composed of a mover 91 and a stator 92, and the mover 91 has an armature including an armature winding part 10. An attachment portion 93 for fixing is attached. For example, the mounting portion 93 corresponds to the portion of the metal frame 15 filled with the resin described above. The stator 92 has a field portion 94 (not shown except for the field portion). The field portion 94 includes a permanent magnet 95 and a field yoke 96, and the inside of the U-shaped field yoke 96. The permanent magnet 95 includes a magnet row in which a non-magnet member such as a positioning groove or mold, a thin plate between magnets, or other magnet members is attached to a plane, or only magnets that are not sandwiched are attached. Thereby, a linear motor with low production cost and high reliability can be obtained.

According to the present embodiment, it is possible to stably reduce the voids and reduce the internal and surface states of the resin after the resin molding of the armature without increasing the thickness of the armature of the linear motor. Defects caused by voids can be reduced, and repair work can be reduced. As a result, the production yield and production time can be reduced, the overall production cost can be reduced, and a low-cost linear motor can be produced.

In the present invention, since the coil fixing strength of the armature is strong, the insulation property is good, and the productivity is high in the linear motor, high product reliability can be ensured, and thus the industrial applicability is great.

It is the perspective view which combined and showed the whole armature of the linear motor in Embodiment 1, and a part of internal state. 3 is a perspective view showing a structure of a single coil constituting the armature in the first embodiment. FIG. FIG. 3 is a diagram showing a first example showing a shape of a bobbin that is a winding core of a coil in the first embodiment. FIG. 3 is a cross-sectional view of a first example of a bobbin shape in the first embodiment. FIG. 5 is a diagram showing a second example showing the shape of the bobbin in the first embodiment. FIG. 6 is a cross-sectional view of a second example of the bobbin shape in the first embodiment. It is the perspective view which showed the whole casting jig in the state which the coil in Embodiment 1 is arrange | positioned, and casts the resin for casting, and a part of internal state. It is sectional drawing of the casting jig | tool of the state in which the coil in Embodiment 1 is arrange | positioned and casting resin is cast. 1 is a perspective view of an entire linear motor in Embodiment 1. FIG.

Explanation of symbols

10 Armature winding part, 11 coil, 12 bobbin, 13 air vent groove, 14 resin,
32 recesses, 92 stators, 95 permanent magnets, 96 field yokes.

Claims (6)

A stator having a plurality of permanent magnets arranged side by side on the field yoke so that the adjacent polarities are different, and a bobbin outer surface on which a part of the outer surface of the bobbin is wound and not wound An armature in which a plurality of coils provided with recesses are fixed with resin ,
In the linear motor configured by arranging the plurality of coils so as to face the magnet array of the permanent magnets,
The bobbin has an air vent groove that partially overlaps with the concave portion, is mixed when the coil is fixed with resin, and extends to a bobbin outer edge in a direction in which air staying in the concave portion is released. motor. 2. The linear motor according to claim 1, wherein the air vent groove extends from a bobbin outer edge in a direction in which air escapes to a bobbin outer edge in a direction opposite to the direction in which air escapes. In a bobbin used for a linear motor armature in which a winding is applied to form a coil and a plurality of the coils are fixed with resin,
A winding is applied to a part of the outer surface, and a recess is provided on the outer surface that is not provided with a winding . The recess and a part of the outer surface overlap, and are mixed when the coil is fixed with resin, and stay in the recess. bobbin and having an air vent groove extends to the bobbin outer edge in the direction of the air escapes. 4. The bobbin according to claim 3, wherein the air vent groove extends from a bobbin outer peripheral edge where air, which is an extension start position, is mixed, to a bobbin outer peripheral edge in a direction in which air escapes. The air vent groove, the linear motor according to claim 1 or 2, characterized by providing a plurality on one side or both sides of the bobbin. The bobbin according to claim 3 or 4, wherein a plurality of the air vent grooves are provided on one side or both sides of the bobbin .

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