JPH0817632A - Demagnetizing method and demagnetizing equipment - Google Patents

Abstract

PURPOSE:To realize a demagnetizing method and a demagnetizing equipment which can be easily installed in an arbitrary place and enables a quick process. CONSTITUTION:A tunnel type demagnetizer 2 is installed around the halfway part of a guide pipe 1 made of plastic resin, and an electromagnetic coil 3 is accommodated in the demagnetizer 2. Electric power is supplied to the electromagnetic coil 3 at a specified excitation frequency from an inverter 4. An introducing inlet 1a of a work 6 is installed on the upper end of a guide pipe 1, and an exhaust vent 1b is installed on the lower end. Buffer material 5 is arranged just below the exhaust vent 1b. The work 6 is demagnetized by the electromagnetic coil 3 while dropping in the guide pipe 1. The guide pipe 1 is so constituted that the inclination angle can be changed by a retaining frame which is not shown in figure. According to the inclination angle, the speed of the work dropping in the guide pipe 1 can be adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a demagnetizing method and a demagnetizing device, and more particularly to a technique for efficiently removing the magnetism of manufactured parts magnetized in a factory.

[0002]

2. Description of the Related Art Conventionally, when a metal part is machined, a work made of a magnetic material may be magnetized during the machining, and the magnetized work may adversely affect the electromagnetic characteristics of the product.
There has been a problem that magnetic powder adheres to the work and interferes with the operation of the movable part of the product. In this case, usually, a method of installing a tunnel type electromagnetic coil to which a voltage of a predetermined frequency is applied during the conveyance of the work by a belt conveyor or the like and inserting a work inside the electromagnetic coil to demagnetize Has been adopted. In addition, a device that generates a periodically varying magnetic field is built into the base of a magnetic material, such as a desktop demagnetizer, and a magnetized work is placed on the base to apply a varying magnetic field to demagnetize. In some cases.

[0003]

The above-described conventional demagnetizing method or demagnetizing device has the following problems. In the method of demagnetizing during the work transfer, it is necessary to provide a transfer means such as a belt conveyor in the middle of the production line, and it is necessary to attach an electromagnetic coil to this transfer means.
When it is installed in the manufacturing line, there is a problem that it is poorly adaptable and it takes time and labor to install it. On the other hand, when using a desktop demagnetizer, it takes time and effort to perform demagnetization work, such as manually placing a work on the base one by one or using a robot, and then removing it from the base again after demagnetizing. Moreover, there is a problem that it is difficult to shorten the demagnetization processing cycle. Therefore, the present invention is to solve the above-mentioned problems, and an object thereof is to provide a demagnetizing method or demagnetizing device that can be easily installed at any place and can perform demagnetizing treatment quickly. To get.

[0004]

Means for Solving the Problems As means for demagnetizing the present invention to solve the above-mentioned problems, a means for demagnetizing a magnetized object is set in advance so as to pass in the vicinity of an electromagnetic coil. The magnetized object is caused to fall along the drop trajectory while a power having a predetermined frequency corresponding to the passing speed of the magnetized object is applied to the electromagnetic coil.

As a demagnetizing device, a falling trajectory of a magnetized product is defined, and an inlet for the magnetized product is provided at an upper part and a discharge part for the magnetized product is provided at a lower part, and the magnetized product is provided. A guide member configured to be guided downward according to gravity, an electromagnetic coil arranged near the periphery of the guide member, and an electric power supply means for supplying electric power of a predetermined frequency to the electromagnetic coil are provided.

In this case, it is preferable that the guide member is constructed so as to be inclined so that the drop trajectory is an inclined trajectory.

Further, it is preferable that the drop orbit is filled with a liquid.

In this case, it is desirable that the liquid is a cleaning liquid for the magnetized material.

[0009]

According to the first aspect of the present invention, the trajectory of the magnetized object is set to pass near the electromagnetic coil, and the electromagnetic coil is supplied with electric power of a predetermined frequency according to the falling speed of the magnetized object near the electromagnetic coil. Since the magnetized material is supplied, the magnetized material can be efficiently demagnetized without the need to provide a special conveying means, and the demagnetization can be quickly performed at any place.

According to the second aspect of the present invention, the guide member defines the falling trajectory of the magnetized object, and the electromagnetic coil is arranged in the vicinity of the periphery of the guide member. Therefore, the magnetized object is not required to be provided. Can be set so as to reliably pass in the vicinity of the electromagnetic coil, and the demagnetization of the magnetized object can be efficiently performed, so that the magnetized object can be easily installed at any place.

According to the third aspect, the falling speed of the magnetized object can be changed by arranging the guide member in an inclined manner. Therefore, the handleability of the magnetized object, the amount of magnetization, the excitation frequency of the electromagnetic coil, the electromagnetic The passing speed of the magnetized material near the electromagnetic coil can be adjusted according to the distance between the coil and the drop trajectory.

According to the fourth aspect, when the drop orbit is filled with the liquid, the falling speed of the magnetized object can be changed by the specific gravity and viscosity of the liquid. It is possible to adjust the passing speed of the magnetized object in the vicinity of the electromagnetic coil according to the excitation frequency of the electromagnetic coil, the distance between the electromagnetic coil and the falling trajectory, and the like.

According to the fifth aspect, by using the liquid as the cleaning liquid, the magnetized material can be demagnetized and simultaneously cleaned.

[0014]

Embodiments of the demagnetizing method or demagnetizing apparatus according to the present invention will be described below. [First Embodiment] In this embodiment, as shown in FIG. 1, a tunnel type demagnetizer 2 is attached to an intermediate portion of a guide pipe 1 made of synthetic resin or the like. An annular electromagnetic coil 3 is housed inside the tunnel type demagnetizer 2.
The guide pipe 1 is inserted therethrough. The electromagnetic coil 3 is connected to an inverter 4, and the inverter 4 is connected to a commercial power supply that supplies 200V three-phase alternating current.

The guide pipe 1 is vertically supported by a support frame (not shown), and is arranged so that the inlet port 1a is at the upper end and the outlet port 1b is at the lower end. Outlet 1
b is arranged at a predetermined height above the floor, and a cushioning material 5 made of a cushion material, a waste cloth or the like is installed just below the outlet 1b. 200V from the inverter 4 in the electromagnetic coil 3
Single-phase AC power having a predetermined frequency is supplied to generate a fluctuating magnetic field. The inverter 4 is configured so that the AC frequency (excitation frequency) supplied to the electromagnetic coil 3 can be adjusted appropriately.

When a magnetized work 6 is introduced into the inlet 1a of the guide pipe 1, the work 6 falls downward inside the guide pipe 1. During this drop, the work 6 is demagnetized by receiving an alternating magnetic field from the electromagnetic coil 3, and then exits from the discharge port 1b and drops onto the cushioning material 5. In order to confirm the demagnetizing effect at this time, the height of the inlet 1a is set to 2,000 m.
m, the height of the electromagnetic coil 3 is 1,000 mm, and the work to be put in has a diameter of 1.5 mm and a length of 15 mm S45.
After preparing 100 pieces of C steel cut wires (made by Toyo Seiko Co., Ltd.), performing a predetermined magnetizing treatment, and measuring the magnetized state of the wires (hereinafter, referred to as a work) by a Hall element,
The demagnetization process was performed as described above. After that, the residual magnetism of each work was measured by a Hall element.

The above measurement results are shown in FIGS. The electromagnetic coil 3 is excited by changing the frequency of the single-phase 200V AC. The current value of the electromagnetic coil 3 was 15.8 A when the frequency was 50 Hz. The frequencies of the AC power supplied to the electromagnetic coil were 25 Hz, 50 Hz, and 100 Hz, and the work was passed through the guide pipe 1 once, twice, and three times, and the measurement was repeated. Under this condition, the demagnetization effect is obtained in all cases of AC frequencies of 25 Hz, 50 Hz, and 100 Hz. However, especially when the frequency is 100 Hz, the entire work is remanently magnetized with a residual magnetic field of 20 after only one pass.
It is demagnetized below G.

The demagnetizing device shown in FIG. 1 is constructed so that the guide pipe 1 can be tilted at an arbitrary angle θ by a support frame (not shown). With this tilting mechanism, the falling speed of the work 6 can be adjusted,
The demagnetization effect can be optimized. For example, a drop that is suitable for handling a work such that the optimum effect can be obtained for the work to be processed while measuring the demagnetization effect, or when processing a fragile or deformable object. The tilt angle of the guide pipe 1 can be adjusted to obtain speed.

7 to 12, the dropping speed of the work 6 in the portion passing through the inside of the electromagnetic coil 3 is 1.4 m.
/ S, 2.9 m / s, two speeds are adjusted, and the AC frequency supplied to the electromagnetic coil 3 at each speed is 5H.
The results measured by changing from z to 200 Hz are shown.
In addition, in Table 1 below, the above results are tabulated and the demagnetization effect when the falling speed of the workpiece 6 is changed is shown for each AC frequency supplied to the electromagnetic coil 3.

[0020]

[Table 1]

The results in Table 1 show the ratio of the magnetized amount of all the workpieces before the demagnetizing process to 100%, and the ratio of the magnetized amount removed by the demagnetizing process. The demagnetization effect is higher when the passing speed of the work 6 is low as a whole. This is considered to be because the effective number of repetitions of the magnetic loop due to the fluctuating magnetic field applied to the work 6 increases as the speed decreases. Further, there is an optimum value of the AC frequency supplied to the electromagnetic coil 3 with respect to the demagnetization effect. This is because the lower the frequency, the smaller the number of repetitions of the magnetic loop, and the higher the frequency, the larger the number of repetitions of the magnetic loop.The higher the frequency, the better.However, the higher the frequency, the larger the inductive reactance of the electromagnetic coil. It is considered that this is because the coil current is reduced and excited to reduce the magnetic flux. This optimum value shifts to the high frequency side as the passing speed of the work 6 increases. Therefore, in order to enhance the demagnetization effect, it is necessary to maintain the passing speed of the work 6 to some extent and to appropriately adjust the AC frequency supplied to the electromagnetic coil 3 according to the passing speed of the work 6.

[Second Embodiment] FIG. 2 is a schematic configuration diagram showing a second embodiment of the demagnetizing apparatus according to the present invention. In this embodiment, the tunnel type demagnetizer 2 is arranged on the side surface side of the press machine 10. At this time, the opening of the tunnel type demagnetizer 2 is set at a position where the work 6 protruding from the die of the press machine 10 passes. When the work 6 is released from the die of the press machine 10, the work 6
Passes through the opening of the tunnel type demagnetizer 2 from the press machine 10 and is accommodated in the work receiver 7 located below the tunnel type demagnetizer 2.

In this embodiment, since the demagnetizer is arranged at the work discharge position of the press machine 10, the demagnetization process can be performed very easily without providing a special guide member. The position of the tunnel type demagnetizer 2 is the work 6
It must be movably supported in accordance with the projecting position of. Further, when the work 6 is prevented from jumping out from the press working machine or the like, the tunnel type demagnetizer 2 is provided directly below the outer end portion of the belt conveyor for carrying out the work 6 from the press working machine. The opening may be arranged.

[Third Embodiment] Next, a third embodiment of the demagnetizing apparatus according to the present invention will be described. In this embodiment, the guide pipe 21 is formed in substantially the same manner as in the first embodiment, an electromagnetic coil 23 is attached to a midway portion of the guide pipe 21, and a sealing cap for closing the discharge port 21b. 24 is attached to the lower end. Guide pipe 21
A cleaning liquid 25 for cleaning the work 26 introduced into the guide pipe 21 is filled in the inside of the container. The cleaning liquid 25 is, for example, various solvents for removing oils and fats attached to the surface of the work 26, a neutral detergent, or the like.

In this embodiment, when the work 26 is put into the inlet 21a of the guide pipe 21, the work 26 slowly sinks in the cleaning liquid 25, passes through the inside of the electromagnetic coil 23, is demagnetized, and then is sealed. It is adapted to be deposited on the bottom end portion which is closed by the stopper cap 24. here,
The sedimentation velocity of the work 26 is the shape and density of the work 26,
And the density and viscosity of the cleaning liquid. Therefore, for a given work 26, the sedimentation speed can be determined by adjusting the cleaning liquid. In this case, similarly to the first embodiment, by arranging the guide pipes 21 so as to be inclined, the sedimentation speed of the work 26 can be further reduced.

In this case, by using the cleaning liquid, it is possible to demagnetize the work 26 and clean the surface of the work 26. However, if a large cleaning effect is not expected, what is filled in the guide pipe 21 is not limited to the cleaning liquid, and may be a simple liquid such as water, alcohol, or glycerin. Generally, by filling the inside of the guide pipe 21 with a liquid, the passing speed of the work 26 with respect to the electromagnetic coil 23 can be reduced, and the demagnetization effect can be improved as shown in the first embodiment. it can.

Although the guide pipe in each of the above embodiments has a circular pipe shape, the guide member has a prismatic shape,
Any shape may be used as long as it can guide the work, such as a trough shape linearly or spirally stretched. Further, the guide member may be formed according to the shape of the work. For example, for a workpiece having a fitting groove on the side surface, a rail-shaped guide that can be slidably fitted in the fitting groove,
For a work having a through hole in the central portion, a wire shape that can be inserted into the through hole may be used. The electromagnetic coil does not have to be an annular solenoid as in the above-described embodiment, and may have an electromagnetic conversion function with a predetermined inductance.

[0028]

As described above, according to the present invention, the falling trajectory of the magnetized object is set to pass near the electromagnetic coil, and the predetermined frequency corresponding to the falling speed of the magnetized object near the electromagnetic coil. By supplying this power to the electromagnetic coil, it is possible to perform processing without providing a special conveying means, and it is possible to perform effective demagnetization processing by the magnetic field generated by the electromagnetic coil according to the falling speed, so that it can be magnetized. It is possible to easily and efficiently perform the demagnetization treatment of the object, and it is possible to speed up the demagnetization process and improve the adaptability or ease of installation of the demagnetization device.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram showing a configuration of a demagnetizing method or a demagnetizing device according to a first embodiment of the present invention.

FIG. 2 is a schematic explanatory diagram showing a configuration of a demagnetizing method or a demagnetizing device according to a second embodiment of the present invention.

FIG. 3 is a schematic explanatory diagram showing a configuration of a demagnetizing method or a demagnetizing device according to a third embodiment of the present invention.

FIG. 4 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 5 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 6 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 7 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 8 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 9 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 10 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 11 is a graph showing an effect of the demagnetizing method or the demagnetizing device according to the present invention.

FIG. 12 is a graph showing the effect of the demagnetizing method or demagnetizing device according to the present invention.

[Explanation of reference numerals] 1,21 Guide pipes 1a, 21a Inlet ports 2b, 21b Discharge port 2 Tunnel type demagnetizer 3,23 Electromagnetic coil 6,26 Work piece 24 Cap member 25 Cleaning liquid

Claims (5)

[Claims] 1. A magnetized object is preliminarily set such that a trajectory of the magnetized object passes near an electromagnetic coil, and a power having a predetermined frequency according to a passing speed of the magnetized object is applied to the electromagnetic coil. A demagnetizing method, characterized in that a magnetized object is dropped along the drop trajectory. 2. A falling trajectory of a magnetized object is defined, and an inlet for the magnetized object is provided at an upper portion and a discharge portion for the magnetized object is provided at a lower portion so that the magnetized object is guided downward by gravity. A demagnetizing device comprising: the guide member configured as described above; an electromagnetic coil disposed near the periphery of the guide member; and a power supply unit that supplies power of a predetermined frequency to the electromagnetic coil. 3. The demagnetizing device according to claim 2, wherein the guide member is arranged so as to be inclined so that the drop trajectory is an inclined trajectory. 4. The demagnetizing device according to claim 2, wherein the drop orbit is filled with a liquid. 5. The demagnetizing device according to claim 4, wherein the liquid is a cleaning liquid for the magnetized object.