JPH1088469A - Iron detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an iron detector having improved detection sensitivity by eliminating the divergence of magnetic force lines generated between the N pole and the S pole of a magnet. SOLUTION: A sewn product transferred by a circulating belt conveyor is passed through a detection part to detect the presence of an iron piece in the sewn product. The detection part 1 of the detector is composed of a permanent magnet 2 placed opposite to a detection member 3 produced by winding a search coil 6 on a long iron core 5. The magnet 2 and the detection member 3 are made of a ferromagnetic metallic material and encircled with a rectangular frame 4 having openings at the front and the rear walls to pass the sewn product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron piece detector and, more particularly, to an iron piece detector for detecting iron pieces such as needles and pins mixed in sewing products.

[0002]

2. Description of the Related Art Various sewing products such as clothes, kimonos, futons and the like use sewing needles, hand sewing needles, waiting pins, dress pins (insect pins), etc. for sewing. In some cases, the iron piece with a sharp point such as a forgot may be forgotten to be removed, or a broken needle may be inserted. Wearing clothes with needles and pins or sleeping on a futon is extremely dangerous because the needles and pins may stick into the body.

Conventionally, a sewing maker inspects a finished sewn product before shipment for iron pieces such as needles and pins or admixes with the inside of the sewn product. Iron pieces were removed from the product. An iron piece detector using a magnetic induction method is used for detecting iron pieces such as needles and pins, and this is abbreviated as a needle detector (instrument).

A magnetic induction system for detecting an iron piece utilizes a static magnetic field generated by a permanent magnet, and passes through a magnetic field formed by lines of magnetic force and strongly reacts with an iron piece having a property of being attracted to a magnet. The presence or absence of an iron piece is detected by an iron core, the induced electromotive force obtained by a search coil is amplified to a certain level, taken out as a signal, and the presence of an iron piece such as a needle or a pin is confirmed.

The iron piece detectors described above include a handy type (needle detector) and a large tunnel type (needle detector). FIG. 5 shows an example of a conventional tunnel-type iron piece detector, which can be roughly divided into a detection section A and a detection display section B. The detection section A is a section for detecting the presence or absence of an iron piece, and forms the center of the detector.
Sewing products such as clothes and kimono are continuously fed on the circulating belt conveyor C and pass through the detection unit A. When it is detected that iron pieces are mixed, the display unit B displays the lamp. The warning is given by flashing or buzzer sound. The display section B also serves as an operation section for driving the entire detector.

FIG. 6 schematically shows a detecting section A used in the above-mentioned tunnel type iron piece detector, which comprises a long permanent magnet a and a pair of detecting members b. The detecting member b is installed facing up and down with the belt conveyor C interposed therebetween. Therefore, the sewn product is placed on the belt conveyor C and moves between the magnet a and the detecting member b in the direction of arrow X1.
Will pass through. The detection member b has a structure in which a copper search coil d that can be energized is wound around an elongated iron core c, and the search coil d is connected to the electronic circuit e of the detection display unit B for detection. Forming a circuit. A magnetic flux space is formed by magnetic lines of force generated between the N pole and the S pole of the magnet a. When a needle or pin passes through the magnetic flux space, the magnetic lines of force change. It is extracted from d as a signal. Therefore, when the sewn product passes through the magnetic field formed by the lines of magnetic force and the iron pieces are mixed, this is detected, and the display unit B notifies the sewn product.

[0007]

However, since the magnet a is open, ineffective magnetic field lines radiated outward are generated in addition to between the N pole and the S pole of the magnet a. Therefore, since the sensitivity is lowered at a position distant from the magnet a and the detection member b, the sensitivity of iron piece detection may be poor. In addition, when the iron pieces (for example, a metal product or a driver worn by a worker) that are not related to the iron pieces for detecting the sewing product pass through the magnetic field lines radiated outward, the detection unit is detected. A has been activated, causing a disturbance to the normal signal required for detection.

The detection member b is formed by winding the search coil d around the iron core c as described above. However, the detection core b has a long shape and the search coil is merely wound. Therefore, since the vibration of the belt conveyor C and the vibration of the drive motor for circulating the belt conveyor C are combined and transmitted to the detection unit A, the vibration affects the search coil d wound only around the iron core c. In this case, the noise signal obscures the valid signal input, causing a detection failure.

The present invention has been made in view of the above-mentioned various problems of the conventional tunnel-type iron piece detector, and has improved the detection sensitivity by eliminating the divergence of lines of magnetic force generated between the N and S poles of the magnet. It is an object of the present invention to provide an iron piece detector having a detection unit in which the influence of vibration generated by a belt conveyor, a motor, and the like is significantly reduced.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to an iron piece which passes a sewn product conveyed by a circulating belt conveyor into a detection section and detects the presence or absence of an iron piece in the sewn product. In the detector, the detection unit 1 is provided with a permanent magnet 2 and a detection member 3 in which a search coil 6 is wound around a long iron core 5 so as to face each other.
Are made of a ferromagnetic metal material, and are surrounded by a rectangular frame body 4 having open front and rear surfaces through which the sewing product passes.

Further, in the iron piece detector which detects the presence or absence of an iron piece in the sewn product by passing the sewn product conveyed by the circulating belt conveyor into the detecting section, the detecting section 1
, Detecting units 7 and 8 in which a permanent magnet 2 and a detecting member 3 in which a search coil 6 is wound around a long iron core 5 are installed facing each other, and both detecting units 7 and 8 are ferromagnetic. It is made of a metal material, and is surrounded by a rectangular frame 4 having both sides through which a sewing product passes. The search coil 6 wound around the iron core 5
The open side of the rectangular frame 4 is surrounded by a shield plate 9 made of a ferromagnetic metal material.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1st Embodiment FIG. 1 and FIG. 2 show an embodiment of a detection unit used in the iron piece detector of the present invention. The detection unit 1 includes a long permanent magnet 2 and a long iron core. It is the same as a conventional detection unit that a pair of two detection members 3 around which a search coil is wound are vertically separated from each other, and in the present invention, the permanent magnet 2 and the detection member 3 It is characterized in that it is surrounded by a rectangular frame 4 made of a metal material, the magnet 2 is fixed in the upper plate of the frame 4, and the detection member 3 is fixed in the lower plate of the frame 4.

The frame 4 has a shape in which both front and rear sides, that is, a front side and a back side, which are the passing directions of the sewn product, are opened. The search coil 6 wound around the iron core 5 is made of an epoxy resin hardener. After being solidified, the coil 6 is electrically connected to an electronic circuit of a detection display unit of a detector (not shown). When the magnet 2 is arranged as in the present embodiment, the magnetic pole is, for example, when the lower surface of the magnet 2 is an N pole, the upper surface of the magnet 2 is an S pole, or vice versa.

The present invention is configured as described above, and is used for a tunnel type iron piece detector. A belt conveyor (not shown) is circulated by a drive motor between a magnet 2 and a detection member 3 which face up and down in a frame 4. It is possible that the sewn product is placed on a belt conveyor, conveyed, and passed through the magnetic field formed by the magnetic lines of force generated between the N pole and the S pole of the magnet 2. If an iron piece is mixed, the iron core 5 detects this, extracts it as a signal from the search coil 6, and notifies the detection display unit by flashing a lamp or a buzzer sound.

Since the magnet 2 and the detection member 3 are surrounded by the frame 4 made of a ferromagnetic material, a strong magnetic flux space is formed between the N pole and the S pole, and it is ineffective that it is oriented in the radiation direction. The magnetic field lines are converged through the frame 4 and the group of convergence is concentrated from the north pole to the south pole, so that the detection sensitivity is extremely good and the generation of noise due to the disturbance of the magnetic field lines directed in the radiation direction is large. The width can be reduced.
The case where the magnet 2 and the detecting member 3 are fixed to the upper plate and the lower plate of the frame body 4 and are vertically opposed to each other has been described. However, the present invention is not limited to this. May be installed so as to face the left and right side plates.

[Second Embodiment] FIG. 3 shows a second embodiment of the detection unit used in the iron piece detector of the present invention.
The same parts as those in the above embodiment use the same reference numerals.
The detecting section 1 in the present embodiment has a symmetrical detecting section 7 in which a pair of detecting members 3 are integrally attached to a long permanent magnet 2,
8 are disposed so as to face each other up and down, and the two detectors 7 and 8 are surrounded by a frame 4 made of a ferromagnetic metal material. One of the detectors 7 is provided in the upper plate of the frame 4. The detectors 8 are fixed in the lower plate of the frame 4 respectively. The search coil 6 wound around the long iron core 5 along the magnet 2 so as to be able to conduct electricity is solidified with an epoxy resin curing agent, and is connected to one detection unit, for example, the N pole surface of the detection unit 7. The S pole face of the other detection unit 8 is opposed.

The present embodiment has the above-described configuration, and the detection units 7 and 8 each including the magnet 2 and the detection member 3 are installed vertically symmetrically in the frame body 4 so that the detection unit 8 is moved from the N pole of the detection unit 7 to the detection unit 8. A strong magnetic flux space is formed on the S pole and the magnetic field lines which are originally ineffective and are directed in the radiation direction are converged through the frame body 4. Since the converged group is concentrated from the N pole to the S pole, the detection sensitivity is extremely good. In addition, it is possible to greatly reduce the generation of noise due to the disturbance of the magnetic field lines directed in the radiation direction. Especially,
In the present embodiment, since the detection members 3 are provided on the upper and lower sides, the iron pieces passing through the magnetic field can be detected by the two cores 5.
The detection range can be expanded.

[Third Embodiment] FIG. 4 shows a third embodiment of a detection unit used in the iron piece detector of the present invention.
The same parts as those in the above embodiments use the same reference numerals. In the present embodiment, the upper and lower plates 4 of the rectangular frame 4
a, a shield plate 9 made of a ferromagnetic metal material having a length of 4b and formed in a U-shape is installed in a symmetrical shape so as to surround the plate members 4a, 4b, and a frame member is left while leaving a passing space for sewing products. 4 is characterized in that it surrounds the open surface of the front and back surfaces.

Since both open surfaces of the frame 4 are surrounded by the shield plate 9 as described above, the lines of magnetic force generated outside are shielded by the shield plate 9, so that the magnets 2 and the detecting member 3 can generate noise generated outside. Unaffected by the frame 4
It does not affect the ability to detect iron pieces contained in sewing products passing through. Further, the frame 4 is formed by the shield plate 9.
The magnetic field lines generated inside can also be prevented from leaking to the outside.

FIG. 4 shows a case where the magnet 2 is provided on the upper plate of the frame 4 and the detecting member 3 is provided on the lower plate. However, the present invention is not limited to this, and the magnet 2 shown in FIG. And detection member 3
The same can be used in the case where the detection units 7 and 8 are integrated.

The shield plate 9 has a shape in which a long plate is fixed to the upper and lower plates 4a and 4b of the frame 4 and both sides in the length direction are bent to surround the open surface in the drawing. Body 4
The N pole of magnet 2 and S
When the poles are not short-circuited, the shield plates 9 may be directly provided on both sides of the frame 4.

In the above description, the case where two detection members 3 are used as a pair has been described. However, the present invention is not limited to this, and one detection member 3 is used to face the magnet 2. May be. Further, in each of the second and third embodiments, the case has been described where the detection units 7 and 8 are disposed to face the upper and lower plates in the frame 4, but the present invention is not limited to this. Alternatively, the detection units 7 and 8 may be installed symmetrically on the left and right side plates in the frame body 4 and a sewing product may be passed between them. Also, the case where the search coil 6 is solidified with an epoxy resin curing agent has been described. However, the present invention is not limited to this. If the search coil 6 does not affect the electrical function of the search coil 6, a hardening material of another material may be used. It is possible to use.

[0023]

According to the present invention described above, the permanent magnet 2 and the detecting member 3 in which the search coil 6 is wound around the iron core 5 are installed facing each other, and the magnet 2 and the detecting member 3 are strengthened. By being surrounded by a rectangular frame 4 made of a magnetic metal material,
Dispersion of the lines of magnetic force generated by the magnet 2 to the outside is significantly reduced, and the lines of magnetic force in the direction of radiation are converged by the frame 4, so that the efficiency of detecting iron pieces mixed in the sewing product can be improved.

Further, the detecting portions 7 and 8 each having the detecting member 3 integrally attached to the permanent magnet 2 are installed so as to face each other, and the detecting portions 7 and 8 are formed in a rectangular frame 4 made of a ferromagnetic metal material. As a result, the radiation of the magnetic field lines generated in the detection units 7 and 8 to the outside is significantly reduced and concentrated between the detection units 7 and 8, so that the efficiency of displaying iron pieces mixed in the sewing product is improved. be able to. In particular, since the iron cores 5 of the detection members 3 are installed facing each other, the detection range of the iron pieces is expanded.

Further, since the search coil 6 wound around the elongated iron core 5 is hardened, the signal obtained is not affected by the vibration generated by the belt conveyor or the drive motor for transporting the sewing products. Can be conveyed reliably. Furthermore, if the open both sides of the frame 4 are surrounded by a shield plate 9 made of a ferromagnetic metal material, the inside of the frame 4 is not affected by external lines of magnetic force, so that the iron pieces mixed into the sewing product are not affected. Detection work can be performed stably.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of a detection unit used in an iron piece detector of the present invention.

FIG. 2 is a plan view of a first embodiment of a detection unit used in the iron piece detector of the present invention.

FIG. 3 is a front view showing a second embodiment of the detection unit used in the iron piece detector of the present invention.

FIG. 4 is a front view showing a third embodiment of the detection unit used in the iron piece detector of the present invention.

FIG. 5 is a perspective view showing an example of a conventional tunnel type iron piece detector.

FIG. 6 is a perspective view of a detection unit used in a conventional iron piece detector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Detecting part 2 Permanent magnet 3 Detecting member 4 Ferromagnetic frame 5 Iron core 6 Search coil 7 Detecting part 8 Detecting part 9 Shield plate A Detecting part B Detection display part C Conveyor a Permanent magnet b Detecting member c Iron core d Search coil

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // G01N 27/90 G01N 27/90

Claims (4)

[Claims] 1. An iron piece detector in which a sewing product conveyed by a circulating belt conveyor is passed through a detection unit to detect the presence or absence of an iron piece in the sewing product, wherein the detection unit 1 includes a permanent magnet 2 and an elongated magnet. A detection member 3 around which a search coil 6 is wound is installed around a simple iron core 5 so as to face the magnet 2 and the detection member 3.
An iron piece detector comprising a ferromagnetic metal material, and surrounded by a rectangular frame 4 having both open front and rear surfaces through which a sewing product passes. 2. An iron piece detector in which a sewing product conveyed by a circulating belt conveyor is passed through a detection unit to detect the presence or absence of an iron piece in the sewing product, wherein the detection unit 1 includes a permanent magnet 2 and a long magnet. Detecting units 7 and 8 which are integrated with a detecting member 3 having a search coil 6 wound around a simple iron core 5 are installed facing each other, and both detecting units 7 and 8 are made of a ferromagnetic metal material, and a sewing product passes therethrough. An iron piece detector, wherein the iron piece detector is surrounded by a rectangular frame body 4 having open front and rear surfaces. 3. The iron piece detector according to claim 1, wherein the search coil wound around the iron core is solidified. 4. The iron piece detector according to claim 1, wherein the open both sides of the rectangular frame 4 are surrounded by a shield plate 9 made of a ferromagnetic metal material.