JPH0641712U - Foreign body attraction magnet - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a magnet for adsorbing a foreign substance in the stomach, which is lightweight and low-priced and has a high adsorption performance for a magnetic foreign substance. A magnet unit in which a plurality of disk-shaped magnets having a pair of magnetic poles on both end surfaces are axially connected to each other through a disk-shaped yoke made of a magnetic material with magnetic poles of the same polarity facing each other.
A non-magnetic cylindrical case that houses the magnet unit and has both ends sealed is formed, and the non-magnetic cylindrical case is formed of a resin material having corrosion resistance.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is intended for the adsorption of foreign substances in the stomach, which is used to adsorb and remove foreign substances composed of magnetic materials such as nails, needles, wires and magnetic powder accumulated by ruminants, especially cows, in the rumen as a result of swallowing. It is about magnets.

[0002]

[Prior art]

 Cattle that feed on grass in the pasture are typical ruminants, and as a result, they swallow the feed without chewing during feeding. Therefore, long, sharp metal pieces such as nails, needles, wires, and magnetic powder that are mixed in the feed, which is grass, or are falling on the pasture, etc., are also ingested with the feed or grass and gather in the rumen, As a result of puncturing the stomach wall with the above-mentioned metal pieces, various diseases including gastritis or digestive disorders may occur, and in extreme cases, perforation of the stomach wall or suppuration of the stomach wall may lead to a fatal accident.

In order to prevent the above-mentioned accidents, for the feed conventionally administered to cattle, metal foreign substances, particularly iron and steel pieces are detected and the feed is controlled by a sorting device. Despite maintenance, cattle fatal accidents often occur as a result of foreign matter in the feed mixed with foreign matter in the feed. For this reason, a permanent magnet or an attraction magnet that is a combination of a magnetic pole piece and a permanent magnet is conventionally retained in the rumen of the cow to adsorb foreign matter made of a magnetic material that has been mistakenly ingested, and puncture damage is caused by a sharp metal piece on the stomach wall. The measures are taken to prevent this.

As this kind of gastric foreign matter adsorption magnet, for example, disk-shaped magnets having magnetic poles of different polarities on both end surfaces are alternately inverted, and magnetic plates are provided between the magnets to coaxially connect them. Those having a combined structure have been proposed (see, for example, Japanese Utility Model Publication No. 57-53550 and Japanese Utility Model Publication No. 60-61703). With such a structure, since there are a plurality of magnetic poles not only at both ends but also in the middle part, even a long thin metal piece is attracted to the middle part of the magnet with its longitudinal direction aligned substantially coaxially. As a result, the effect of not puncturing the stomach wall is expected.

However, all of the above-mentioned attraction magnets are composed of ferrite magnets, and the magnetic force is insufficient. That is, the surface magnetic flux density of the gastric foreign matter adsorption magnet is only 1600 to 1800G, and a sharp metal piece can be adsorbed and held coaxially on the surface of the adsorption magnet so as not to puncture the stomach wall. There is a problem that you cannot do it. In addition, since the above-mentioned adsorption magnet has a structure in which a porous sintered ferrite magnet is exposed, it has a problem that it has a very short life as a result of being eroded by gastric juice during use and missing from the outer surface.

In order to solve these drawbacks, therefore, a foreign substance adsorption magnet in the stomach is housed in a case made of a corrosion-resistant non-magnetic material, which is a cylindrical body in which a rare earth / iron / boron magnet and a yoke are axially connected to each other. Have been proposed (see US Pat. No. 5,096,763).

[0007]

[Problems to be solved by the device]

 According to this foreign substance adsorption magnet in the stomach, since the surface magnetic flux density at the intermediate portion is larger than at both ends, even a long thin foreign substance such as a nail or a wire can be adsorbed and held substantially coaxially. Since the puncture of the stomach wall by the tip of the can be completely prevented, there is an advantage that the life is long.

However, there is still some room for improvement in this magnet for attracting foreign substances in the stomach. That is, since stainless steel such as SUS304 is used as the above-mentioned corrosion resistant material, it cannot be said to be sufficient in that the weight is relatively large and the price is relatively large.

Therefore, an object of the present invention is to provide a gastric foreign matter attracting magnet that is lightweight and inexpensive, and has a high ability to attract magnetic foreign matters.

[0010]

[Means for Solving the Problems]

 In order to achieve the above object, in the present invention, a disk-shaped magnet having a pair of magnetic poles on both end surfaces is axially connected through a disk-shaped yoke made of a magnetic material with magnetic poles of the same polarity facing each other. A magnet unit, and a non-magnetic cylindrical case that houses the magnet unit and has both ends sealed, in which case the non-magnetic cylindrical case is formed of a resin material having corrosion resistance. Adopted technical means.

[0011]

[Action]

 With the above configuration, since the cylindrical case that houses the magnet unit is made of a resin material having corrosion resistance, a lightweight and inexpensive gastric foreign body magnet can be obtained. Moreover, since the intermediate magnetic force of the attracting magnet can be made larger than that at the end portion, even a thin metal piece can be attracted and held preferentially and substantially coaxially on the intermediate surface of the case. .

[0012]

【Example】

 The details of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a foreign substance adsorption magnet in a stomach showing an embodiment of the present invention. In the figure, 1 is a magnet unit, which is composed of a disk-shaped permanent magnet 2 magnetized in the thickness direction and provided with a pair of magnetic poles (N, S) on both end surfaces, and a magnetic body such as iron or steel. Disc-shaped yokes 3 are alternately connected, and adjacent permanent magnets 2 are arranged so that magnetic poles having the same polarity face each other. Reference numeral 4 denotes a bottomed cylindrical case, 5 denotes a cap that seals the open end of the case 4, and each is made of a resin material having corrosion resistance.

In this attraction magnet, the disk-shaped magnet can be formed of a known permanent magnet material such as a ferrite magnet or a rare earth magnet, but from the viewpoint of attraction performance, a rare earth element such as R (Nd, Pr, Dy) is used. 1) or more) -Fe-B based material (see US Pat. No. 5,096,763).

The resin material for forming the case 4 and the cap 5 is a thermosetting resin such as phenol resin, epoxy resin, diallyl phthalate resin, unsaturated polyester resin, silicone resin, or bismaleicidriadine resin from the viewpoint of corrosion resistance. It is preferable to use a polar resin. If it is necessary to further increase the strength of the case, the resin material may be molded by adding an appropriate amount (about 10 to 40% by weight) of a filler such as glass fiber or carbon fiber.

In order to assemble the above-mentioned attracting magnet, the disk-shaped magnets 2 and the disk-shaped yokes 3 magnetized in the thickness direction are inserted into the case 4 alternately so that the magnetic poles of the same polarity face each other, Next, a circumferential groove 41 may be formed on the inner peripheral surface of the case 4, annular projections 51 may be provided on both outer ends of the cap 5, and the projection 51 may be fitted into the circumferential groove 41.

FIG. 2 is a cross-sectional view of a gastric foreign matter adsorption magnet according to another embodiment of the present invention, and the same parts as those in FIG. 1 are designated by the same reference numerals. This attracting magnet is one in which the magnet unit 1 is housed in an integrally formed case 42. For example, the magnet unit 1 is inserted into a molding die and then cured with a thermosetting resin in the molding cavity. It can be obtained by filling a composition containing an agent and then heating and curing.

In FIG. 3, the magnet unit in FIG. 1 is composed of an Nd-Fe-B system magnet (HS-30BV manufactured by Hitachi Metals) having an outer diameter of 14 mm and a thickness of 4 mm and a yoke having an outer diameter of 14 mm and a thickness of 4.5 mm. The surface magnetic flux density distribution in the axial direction of the adsorption magnet formed of (SS-41) and having the case 1 and the cap made of phenolic resin is shown. From FIG. 3, the adsorption magnet of the present invention has a high surface magnetic flux density of 2600 to 3000 G (1.4 to 1.9 times that of the ferrite magnet) and a magnetic flux density of the middle portion is larger than that of the end portion, so that the adsorption performance is excellent. It is understood that it has.

[0018]

[Effect of device]

 As described above, according to the present invention, it is possible to obtain a lightweight and inexpensive foreign substance adsorption magnet in the stomach having a high adsorption performance for magnetic foreign substances.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a partial sectional view showing another embodiment of the present invention.

FIG. 3 is a diagram showing an axial surface magnetic flux waveform in the present invention.

[Explanation of symbols]

 1 Magnet unit 2 Disc-shaped permanent magnet 3 Disc-shaped yoke 4 Cylindrical case

Claims (1)

[Scope of utility model registration request] 1. A magnet unit in which a plurality of disk-shaped magnets having a pair of magnetic poles on both end surfaces are axially connected via magnetic disk-shaped yokes with magnetic poles of the same polarity facing each other. In a gastric foreign matter adsorption magnet having a non-magnetic cylindrical case that houses the magnet unit and is sealed at both ends, the non-magnetic cylindrical case is formed of a resin material having corrosion resistance. Attraction magnet.