JPH04358617A - Electromagnet for electromagnetic vibrator - Google Patents

Abstract

PURPOSE:To decrease an air gap between a movable core and an iron core so as to maintain an effect of an electromagnet by coating a magnetic pole surface of at least the iron core of all the units of a coil and the iron core, wound with the coil, with a glass cloth or fiber reinforced synthetic resin film and the other with ordinary synthetic resin by molding. CONSTITUTION:A part except magnetic pole surfaces S1, S2, S3 of an iron core 29 of a total unit of the iron core 29 and a coil 30, wound on this iron core, is molded by epoxy resin M to form a thin film of glass cloth 80 in these exposed magnetic pole surfaces S1 S2, S3. This coating film may be reinforced synthetic resin. As a result, even when jetted water is sprayed to this film, water is prevented from directly hitting the iron core 29 and the coil 30, and the iron core 29 is prevented from rusting to maintain insulation of the coil 30 also well over a long period.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnet for, for example, a small electromagnetic vibration feeder.

0002

[Prior Art and its Problems] FIG. 5 shows the main parts of a conventional small-sized electromagnetic vibration feeder. The trough 1 is fixed to a frame 2 with bolts 60, and this frame 2 is connected to a base 5. They are connected by a pair of front and rear inclined leaf springs 3 and 4. The base 5 is vibration-proofly supported on the ground by coil springs 11 and 12. An electromagnet mount 6 is integrally formed on the base 5, and an E-shaped iron core 7 is fixed to this, and a coil is wound around this. Further, a movable core 9 is fixed to the frame 2, and a gap g is formed between this and the iron core 7. A coil lead wire 10 is led out from the coil 8.

The conventional small electromagnetic vibration feeder is constructed as described above, but when alternating current is applied to the coil 8, an alternating magnetic attraction force is generated between the iron core 7 and the movable core 9, as is well known. As a result, the trough 1 performs linear vibration in the direction a, which is substantially perpendicular to the leaf springs 3 and 4.

[0004] Such electromagnetic vibration feeders are widely used in various industrial fields, but recently they have also been used to transfer pharmaceutical powders, etc., and the measurement accuracy must be high. When transferring other medicines, if the powder of the previous medicine adheres to the trough 1 or other parts, it will have a negative effect on the efficacy of the medicine. Cleaning is done by spraying water all over. For this reason, stainless steel is used for the trough 1, and the base 5 and movable core 9 are plated, so they will not rust even when sprayed with water and will not be adversely affected by it, but the iron core 7 cannot be plated. The coil 8 is taped and impregnated with varnish to form a coating, but this is insufficient and often leads to the iron core 7 eventually becoming rusted or the coil 8 being damaged. For this reason, even if a predetermined current is applied to the coil 8, the trough 1 may not be able to obtain a predetermined swing width due to current leakage or poor insulation in the coil 8, or rusting of the iron core 7.

[0005] In view of the above-mentioned problems, the present applicant has devised a method to ensure the original characteristics of electromagnetic vibration equipment, such as pharmaceuticals, which require washing with water each time the type changes. The object of the present invention is to provide an electromagnet for an electromagnetic vibrator, which is characterized in that a coil and an iron core around which the coil is wound are entirely coated with synthetic resin by molding. Ru. Alternatively, this can be achieved by an electromagnet for an electromagnetic vibrator, characterized in that the entire outer surface of a coil and an iron core around which the coil is wound is powder-coated. Alternatively, there is provided an electromagnet for an electromagnetic vibrator, characterized in that a coil and an iron core around which the coil is wound are immersed in a resin solution to form a coating of the resin on the entire surface thereof. (Utility Application No. 3-9552). For example, even if such an electromagnet is washed with water each time the type of medicine changes, the coil or iron core will not come into direct contact with water, and therefore the coil or iron core will not be adversely affected by water. Therefore, the characteristics of the electromagnetic vibrator equipped with this coil and iron core can be guaranteed over a long period of time.

However, the above electromagnet for an electromagnetic vibrator has the following drawbacks.

For example, a movable core is fixed to the bottom of the trough of an electromagnetic vibration feeder, and this and the above-mentioned iron core face each other with a gap of, for example, 1.0 mm, and the iron core is fixed to the base. ing. The core and coil are entirely molded with synthetic resin, and the gap between the movable core and the core cannot be made smaller than this thickness, and this is the minimum value for the electromagnetic vibration feeder. The gap must be set in consideration of the desired swing width of the trough so that the movable core does not impact the iron core. If the air gap between the moving core and the iron core is made large enough to prevent shock, the leakage flux will naturally increase, and therefore a large current must flow through the coil to give the same amplitude to the trough. , increase the capacity of the coil winding, or generate Joule heat, which adversely affects surrounding members. Therefore, the distance between this movable core and the surface of the synthetic resin covering the magnetic pole face of the iron core must be made as small as possible. However, the current flowing through the coil is not always constant, and the load on the trough may fluctuate, causing the amplitude of the trough to change.
The proximity of the movable core to the iron core may become smaller. As is well known, as the air gap becomes smaller, the magnetic attraction force increases rapidly (not linearly) if the applied voltage is constant, and if the distance between the initial movable core and the magnetic pole face of the iron core is If it is kept small, a slight variation in the power supply voltage and a slight variation in the load on the trough will cause the moving core to impact the iron core. This will damage the synthetic resin covering the surface of the core, exposing the core. This does not serve the initial purpose, and water will splash directly on it, causing the area to rust.

[0008]

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned problems, and improves the effect of the electromagnet for an electromagnetic vibrator proposed previously while further reducing the gap between the movable core and the iron core of the electromagnetic vibrator. An object of the present invention is to provide an electromagnet for an electromagnetic vibrator that can be maintained.

[0009]

[Means for solving the problem] The above object is to provide a coil and an iron core around which the coil is wound, at least at least the magnetic pole face of the core being covered with glass cloth or a fiber-reinforced synthetic resin film, and the rest being covered with a glass cloth or a fiber-reinforced synthetic resin film. This is achieved by an electromagnet for an electromagnetic vibrator, which is characterized by being coated with a common synthetic resin by molding.

0010

[Operation] The magnetic pole surface of the iron core facing the movable core fixed on the movable side of the electromagnetic vibrator is covered with glass cloth or reinforced synthetic resin material, making its strength much higher than that of ordinary synthetic resin. can do. Therefore, the thickness of the film that covers the magnetic pole surface and prevents water from directly splashing can be made smaller than in the previous proposal. Therefore, for example, the initial gap between the movable core and the iron core can be made smaller for the same predetermined amplitude of the trough of the electromagnetic vibration feeder. Also, even if the amplitude of the movable part increases due to power supply voltage fluctuations and the iron core is struck,
Glass cloth or reinforced synthetic resin has great strength and will not break. Therefore, even if you constantly spray water to clean it, the entire body, including the iron core and coil, will not come into direct contact with water.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An electromagnetic vibration feeder according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a small electromagnetic vibration feeder, which is used, for example, to transfer pharmaceutical powder. The trough 21 is made of stainless steel, and its shape is shown in FIG.
3 is fixed by welding, and a base block 24 is supported below this by vibration isolating springs 27 and 28. The frame 22 and the leaf spring mounting member 23 are connected to the base block 24 by a pair of front and rear inclined stacked leaf springs 25 and 26. Base block 24 and leaf springs 25, 26
is plated, and an electromagnet drive section E according to the present invention is fixed to the core attachment section 24a of the base block 24. An iron block 3 is provided with a gap g' in this electromagnet drive part E.
1 is fixed to the leaf spring mounting member 23, which is also plated. The electromagnet drive section E is formed by laminating a large number of silicon steel plates, and has a known structure, for example, an E-shaped iron core 29 and a coil 30 wound around the central magnetic pole section 29a. The coil 30 also has a known structure in which a predetermined number of turns of electric wire is wound around a bobbin, and the surface thereof is taped and subjected to surface treatment to impregnate with varnish. Further, the lead terminal 39 of this coil 30 is fixed to the above-mentioned core mounting portion 24a via a terminal mounting plate 32.

According to the present invention, among the entire core 29 and the coil 30 wound around it, the magnetic pole face S1 of the core 29,
The parts except S2 and S3 are molded with epoxy resin M, so the entire surface is the same as the magnetic pole faces S1 and S
2 and S3 are coated with a layer M made of epoxy resin. Due to the molding, the overall shape is a rectangular parallelepiped.

FIG. 2 shows the related structure of the E-type iron core 29 and the coil 30 in more detail. The coil 30 is wound around a bobbin 81 in a well-known manner, and the center opening 8
The central magnetic pole P1 of the iron core 29 is inserted through 1a. In this state, as described above, the central magnetic pole P1 is molded with epoxy resin M, and the magnetic poles P2 and P2 on both sides thereof are molded.
The three magnetic pole faces S1, S2, and S3 are molded while being exposed. At this time, depending on the case, a very thin coating of epoxy resin M may be formed on the magnetic pole surface.

According to the present invention, this exposed magnetic pole face S1
, S2, and S3 are coated with a thin glass cloth 80. This coating may be made of a reinforced synthetic resin.

A portion of the iron core 29 facing the movable core 31 is thinner than other portions. This thickness is sufficiently small, and the distance g' from this membrane surface to the opposing surface of the movable core 31 is, for example, 1 mm, which hardly changes even if the thickness of the membrane 80 is added. Even if the coil 30 is excited with such a gap g'+film thickness, the magnetic flux that leaks is almost the same as in the conventional case. In order to reduce the leakage magnetic flux in the air gap g',
Furthermore, in order to reduce the current flowing through the coil 30, if the current is made as small as possible, even if the magnetic attraction force is obtained by reducing the amplitude, the magnetic attraction force will suddenly increase due to a slight increase in voltage. However, although the iron core 29, ie, the layer of glass cloth 80 according to this embodiment collides with the movable core 31, the membrane 80 is not destroyed.

As described above, a lead terminal 39 is led out from the coil 30, and an AC power source is connected to this terminal as is known in the art. The entire electromagnet drive section E is attached to the electromagnet mounting section 24a with bolts 66 via a mounting plate 65.

The electromagnetic vibration feeder according to the embodiment of the present invention is constructed as described above, and its operation will be explained next.

The coil 30 is energized, for example, by half-wave rectifying a commercial power source, as in the conventional case. As a result, an alternating magnetic attraction force is generated between the iron core 29 and the movable core 31, and the trough 2
1 performs linear vibration in a direction substantially perpendicular to the longitudinal direction of the stacked leaf springs 25 and 26. Therefore, although not shown, the pharmaceutical powder supplied into the trough 21 is transferred to the right at a speed corresponding to the width of the trough 21.

The electric current applied to the coil 30 can be set to approximately the same magnitude as in the conventional case, and approximately the same amplitude can be obtained in the trough 21. If you want to feed powder of a type of medicine using the same electromagnetic vibration feeder, the powder of the previous medicine should not be mixed with the powder because it is a medicine. Even if the powder adheres not only to the trough 21 but also to other parts, such as the electromagnet driving part E, depending on the environment, the powder that will be scattered may mix with the next type of powder in the trough 21. In such a case, it may be dangerous depending on the formulation, so if you want to transfer a different type of powder, remove the trough 21 and wash it with water, and also eject the electromagnet drive section E, leaf springs 25, 26, base block 24, etc. Wash with water. Therefore, after the powder of the previous medicine is washed away from all parts and the whole is dried in a clean state, the powder of the next medicine is poured into the trough 2.
1, and the powder is supplied in the same manner as described above by driving the electromagnetic drive section E.

The embodiment of the present invention has the above-described structure and operation, and has the following effects.

That is, in the conventional electromagnetic vibration feeder, the iron core 7 and the coil 8 wound around it are exposed to the air, so when water is jetted onto the iron core 7 to clean it, it is natural that the iron core 7 is exposed to the air. However, water will adhere to the surface of the coil 8, and the iron core 7 will eventually rust, and the oil-impregnated surface of the coil 8 will become bald, causing the internal lead wire to become bald. There was a risk that the material would be exposed or the insulation would be poor. This makes it impossible to obtain a stable supply effect of the electromagnetic vibration feeder over a long period of time, and in some cases, the wire may break and no driving force is generated.

However, according to the embodiment of the present application, the entire iron core 29 and the coil 30 wound around it are arranged on the magnetic pole faces S1 and S2.
, S3 are molded with epoxy resin M, and the magnetic pole faces S1, S2, and S3 are covered with glass cloth 80 or reinforced synthetic resin, so even if water is splashed on them, the cores 29 and Water is prevented from directly hitting the coil 30, and the iron core 29 does not rust.
Further, the insulation properties of the coil 30 are maintained well over a long period of time. Therefore, the electromagnetic vibration feeder equipped with the present electromagnetic drive section E can reliably perform the desired function over a long period of time. Furthermore, even if the gap g' is made small and the movable core 31 collides with the iron core 29, the glass cloth 80 or the reinforced synthetic resin has high strength and will not be damaged.

FIG. 4 shows an electromagnet driving section F according to a second embodiment of the present invention, but the other structure of the electromagnetic vibration feeder equipped with this is the same as that of the first embodiment, and will therefore be omitted.

According to this embodiment, the iron core 43 has a shape similar to that shown in FIG. 1 by compacting iron powder with a binder, but it is wound with a coil 42 as in the first embodiment.
By dipping the movable core 41 and the coil 4 wound around the movable core 41 in an epoxy resin solution,
2, an epoxy resin film m is formed on this surface. Movable core 4 of epoxy resin m of iron core 43
1, that is, the magnetic pole faces 43a, 43b, 43
A coating of glass cloth or reinforced synthetic resin 90 is formed on c. Note that during dipping into the epoxy resin solution, the magnetic pole surfaces 43a, 43b, and 43c are masked to prevent them from adhering.

It is clear that the same effect as in the first embodiment is achieved, but in addition, according to this embodiment, the entire core 43 and the coil 42 wound around it are coated with an epoxy resin film m by a dipping method. Since the first embodiment requires a formwork, this embodiment does not require such a formwork, so that costs can be further reduced. Note that the electromagnet drive unit F of this embodiment also has a mounting plate 44.
It is fixed to the base block by the iron core 43.
It may be integrally molded with.

Although not shown, a waterproof film may be formed on the entire surface of the iron core and the coil wound thereon by so-called powder coating, except for the magnetic pole surface. It is clear that even in such a case, the same effects as in the first and second embodiments can be achieved. In this case as well, the magnetic pole surface may be masked.

Although each embodiment of the present invention has been described above, the present invention is of course not limited to these, and various modifications can be made based on the technical idea of the present invention.

For example, in the above embodiments, an electromagnetic vibration feeder was explained as the electromagnetic vibrator, but the present invention can also be applied to the drive part of an electromagnetic vibrator that is attached to the outer wall of a hopper to prevent bridging and material clogging. You may.

Furthermore, in the above embodiments, the present invention was applied to an E-type electromagnet and a coil wound around the E-type electromagnet, but it is of course possible to apply the present invention to electromagnets of other shapes, such as cylindrical iron cores. .

Furthermore, in the above embodiments, the film of glass cloth or reinforced synthetic resin was formed only on the magnetic pole face of the iron core, but this is not restrictive, and other parts, for example, the entire surface of the iron core, may be coated with these materials. Alternatively, the entire core and coil may be covered with glass cloth or a reinforced synthetic resin film.

[0032]

As described above, according to the electromagnet for an electromagnetic vibrator of the present invention, the performance of the electromagnet driving section can be guaranteed for a long period of time even when cleaning is performed by jetting and spraying water, for example. In addition, the air gap between the movable core and the magnetic pole surface of the opposing iron core can be made as small as possible, so that the magnitude of the current flowing through the coil can be made as small as possible for a given amplitude of the movable part. Furthermore, even if the movable core were to collide with the iron core, the glass cloth or reinforced synthetic resin would not be damaged because of its high strength, and its properties could be maintained.

[Brief explanation of drawings]

FIG. 1 is a side view of essential parts of an electromagnetic vibration feeder according to a first embodiment of the present invention.

FIG. 2 is a sectional view of an electromagnet drive section in the electromagnetic vibration feeder according to the first embodiment.

FIG. 3 is a front view of the electromagnetic vibration feeder of FIG. 1;

FIG. 4 is a sectional view of an electromagnet drive section in an electromagnetic vibration feeder according to a second embodiment.

FIG. 5 is a side view of a conventional electromagnetic vibration feeder.

[Explanation of symbols]

29 Iron core 30 Coil 42 Coil 43 Iron core E Electromagnetic drive section F　　　　　　Electromagnet drive part M Epoxy resin layer m Epoxy resin layer S1 Magnetic pole surface S2　　　　　Magnetic pole surface S3　　　　　Magnetic pole surface 43a Magnetic pole surface 43b Magnetic pole surface 43c Magnetic pole face 80 Glass cloth membrane 90 Glass cloth membrane

Claims (3)

[Claims] Claim 1: Out of the whole of the coil and the iron core around which the coil is wound, at least the magnetic pole face of the iron core is covered with glass cloth or fiber-reinforced synthetic resin film, and the rest is covered with ordinary synthetic resin by molding. An electromagnet for an electromagnetic vibrator, which is characterized by: 2. The electromagnetic vibrator according to claim 1, wherein the entire outer surface of the coil and the iron core around which the coil is wound or a portion other than the magnetic pole surface is powder coated. Electromagnet for use. 3. A coating of the resin is formed on the entire surface of the coil by immersing the entire coil and the iron core around which the coil is wound, or a portion other than the magnetic pole surface, in a resin solution. The electromagnet for an electromagnetic vibrator according to claim 1, characterized in that: