JPH0624881U - Electromagnet for adsorption and transfer of small parts - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an electromagnet for adsorbing and transferring small parts, which can prevent small parts from being separated from the adsorption surface due to the presence of oil. In an electromagnet for adsorbing and transferring small parts, which is configured by combining an electromagnetic coil, a core made of a ferromagnetic material, and a yoke, a large number of small parts are adsorbed on the adsorbing surface 4 of the small parts. The groove 5 is formed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electromagnet for adsorbing and transferring small components, which is configured by connecting an electromagnetic coil, a yoke made of a ferromagnetic material, and a core.

[0002]

[Prior art]

 Conventionally, there is known a method of transferring small iron or steel parts by utilizing the magnetic attraction of an electromagnet. There are various structures for the electromagnet in this case, but all of them are constructed by connecting a ferromagnetic core and a yoke to the electromagnetic coil, and the end face of the core and the end face or side face of the yoke are connected to the small parts. It has a flat surface for adsorbing.

That is, an electromagnet for adsorption transfer is introduced into a container (passage, etc.) accommodating a large number of small parts, and when the adsorption surface contacts the small parts group, the electromagnetic coil is energized to Adsorbs small parts. By moving the adsorption / transfer electromagnet to another place while maintaining the adsorbed state, the adsorbed small component can be transferred. At the destination of small parts, the electromagnetic coil is de-energized and the magnetic attraction is released to release the small parts that have been adsorbed.

Even if the electromagnetic coil is de-energized, there is residual magnetism on the attracting surface and small parts, and in particular, there is a problem that some lightweight parts such as small parts do not leave the attracting surface. . A method has been developed to control the energization of the electromagnetic coil so that there is no residual magnetism that is inconvenient for the suction transfer of such small parts (for example, Japanese Patent Application No. 3-78428 of the same applicant).

[0005]

[Problems to be solved by the device]

 When using the electromagnet for adsorbing and transferring small parts as described above, when adsorbing, transferring, and separating small parts, if the small parts are thin plate members and oil such as processing oil adheres, There was such a problem.

That is, oil enters between the small parts and the attraction surface of the electromagnet, and the small parts are attracted to the attraction surface via the oil, and the surface tension of the oil acts between the small parts and the attraction surface. Will be like. Therefore, in the case of lightweight parts such as small parts, even if the electromagnetic coil is energized so that there is no residual magnetism, the surface tension may prevent complete removal of the small parts. There was a point.

[0007]

[Means for solving the problem]

 The present invention has been made in view of the above problems, and an object thereof is to provide an electromagnet for adsorbing and transferring small parts, which can prevent the small parts from being separated from the adsorption surface due to the presence of oil. .

The electromagnet for adsorbing and transferring small parts of the present invention that achieves the above object is an electromagnet for adsorbing and transferring small parts, which is configured by combining an electromagnetic coil, a core made of a strong magnetic material, and a yoke. Also, in the yoke, a large number of grooves are formed in the suction surface of the small component.

It is desirable to form a flat surface between the grooves of the plurality of grooves so as to form a surface in contact with the flat surface of the small component.

The groove has any cross-sectional shape and can be triangular, rectangular or U-shaped.

[0011]

[Action]

 According to the electromagnet for adsorbing and transferring small parts of the present invention, since a large number of grooves are formed in the adsorbing surface, the contact area between the adsorbing surface and the small parts can be made small, and even if oil is present, the attraction due to surface tension The force can be reduced and the obstacles to withdrawal can be eliminated. It is especially effective for small parts made of thin plate members.

Further, a gap is formed by the groove in the contact surface between the suction surface and the small component, and when the electromagnetic coil is cut off to separate the small component, a demagnetizing field is generated by the gap. The effect of canceling the residual magnetism can be increased.

[0013]

【Example】

 FIG. 1 shows electromagnets for adsorbing and transferring small parts according to various embodiments of the present invention.

(A) is a first embodiment, which comprises an iron core 1, iron-made disk-shaped yokes 2 a, 2 b, and an electromagnetic coil 3. As shown in FIG. 2 (a), grooves 5 and 5 having a triangular cross section are formed in concentric circles on the outer surface of the yoke 2a which is the attraction surface 4.

(B) is a second embodiment, which comprises an iron core 1, iron-made yokes 2c and 2d having an L shape, and an electromagnetic coil 3. Grooves 5 and 5 having a triangular cross section are formed in parallel with each other on the side surfaces of the yokes 2c and 2d to be the attraction surface 4, as shown in FIG. 2 (b).

(C) is a third embodiment, in which the core 1 and the yoke 2 are integrally made of iron, and the electromagnetic coil 3 is mounted around the core 1. As shown in FIG. 2 (c), grooves 5 and 5 each having a triangular cross section are formed obliquely in parallel with each other on the end faces of the core 1 and the yoke 2 which become the attraction surface 4.

Next, (d) is a fourth embodiment, in which a plurality of electromagnets 6 each including a core 1, a yoke 2, and an electromagnetic coil 3 (in the case of four in the figure, However, the present invention is not limited to this and is provided. Grooves 5 and 5 each having a triangular cross section are formed in the end faces of the core 1 and the yoke 2 serving as the attraction surface 4 of each electromagnet 9 as shown in FIG. 2 (d).

FIG. 3 illustrates the action of the attraction surface 4 of the electromagnet for adsorbing and transporting small parts of the above embodiment. Reference numeral 7 in the drawing denotes a small component that is sucked onto the suction surface 4. As shown in the figure, it is desirable to form a flat surface 8 between the grooves 5 and 5 formed in the suction surface 4 so as to secure an area S in contact with the small component 7 to some extent.

As shown in the figure, the area of the contact surface where the suction surface 4 and the small component 7 come into contact with each other due to the large number of grooves 5 and 5 formed in the suction surface 4 is the area of the flat surface 8. As a result, it is possible to reduce the size as compared with the case where all the suction surfaces 4 are flat surfaces. As a result, even if the oil adheres to the surface of the small component 7, the surface tension of the oil can be reduced, and the trouble caused by the oil adhering at the time of separation, which is performed by cutting off the power supply to the electromagnetic coil 3, is eliminated. can do.

The attraction force F when the electromagnetic coil 3 is energized is represented by the equation (1).

[0021]

[Equation 1]

K is a constant, μ is the magnetic permeability of the small component 7, B is the magnetic flux density, and S is the area of the flat surface where the suction surface 4 and the small component 7 contact.

By forming the grooves 5 and 5 on the attracting surface 4, the contact area S is reduced, but the magnetic flux density B is increased, and the increase of the magnetic flux density B is effective as the square of the attracting force F. Therefore, the magnetic attraction force does not decrease.

FIG. 4 is a diagram showing a waveform of a current passed through the electromagnetic coil 3. The section P ₁ is an attraction section in which a current is passed through the electromagnetic coil 3 to obtain an attraction force, and the sections P _{2 to} P ₄ are sections in which the current passed through the electromagnetic coil 3 is cut off to release the attraction force. . In the section where the attraction force is released, in order to prevent residual magnetism from remaining on the attraction surface 4 and small parts 7, the current is set to 0 at P ₂ and then the time interval of P ₃ (for example, 0.1 sec) after placing, to flow through degaussing current in the interval P _4. Various methods can be used for the degaussing current, that is, (a) attenuated AC, (b) square pulse, (c), (d) triangular pulse, and (d) square pulse and attenuated AC (details). Was disclosed in Japanese Patent Application No. 3-78428).

As described above, the demagnetization control can be performed so that the residual magnetism is reduced by the current passed through the electromagnetic coil 3. In particular, when the grooves 4 and 4 are formed in the attracting surface 4 as in this invention, a demagnetizing field as shown by the dotted line is formed in the void of the groove 4 during demagnetization control as shown in FIG. As a result, in the hysteresis loop shown in FIG. 3 (b), the residual magnetic flux density can be reduced from the point A to the point B in the case where all are flat surfaces by following the path indicated by the dotted line.

Although the embodiment has been described above, the groove 5 having a triangular cross section may have another groove shape such as a rectangular cross section or a (reverse) U shape.

[0027]

[Effect of device]

 As described above, according to this invention, there is an effect that it is possible to provide an electromagnet for adsorbing and transferring small parts, which can reliably detach even small parts to which oil is attached.

[Brief description of drawings]

1 is a sectional view of an embodiment of the present invention, (a) is a first embodiment, (b) is a second embodiment, (c) is a third embodiment, and (d) is a fourth embodiment.
This is an example.

FIG. 2 is a bottom view of the same embodiment, in which (a) is the first embodiment, (b) is the second embodiment, (c) is the third embodiment, and (d) is the fourth embodiment. Is.

3A and 3B are diagrams for explaining the operation of the embodiment, in which FIG. 3A is an enlarged cross-sectional view of a suction surface, and FIG. 3B is a diagram of a hysteresis loop.

FIG. 4 is a diagram of a waveform of a current passed through an electromagnetic coil according to an embodiment,
(a) uses a damped AC current, (b) uses a square pulse current, (c) and (d) uses a triangular pulse current, and (e) uses a square pulse and a damped AC current. FIG.

[Explanation of symbols]

 1 core 2, 2a, 2b, 2c, 2d yoke 3 electromagnetic coil 4 adsorption surface 5 groove 7 small parts 8 flat surface

Claims (3)

[Scope of utility model registration request] 1. An electromagnet for adsorbing and transporting small parts, comprising an electromagnetic coil, a core and a yoke made of a ferromagnetic material, and a large number of grooves are formed in an adsorbing surface of the small parts in the core and the yoke. An electromagnet for adsorbing and transferring small parts, characterized by being provided. 2. The electromagnet for adsorbing and transferring small parts according to claim 1, wherein a flat surface is formed between the grooves. 3. The electromagnet for adsorbing and transferring small parts according to claim 1 or 2, wherein the groove has a cross section, a triangle, a rectangle or a U shape.