JP3430319B2 - electromagnet - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnet, and more particularly to an electromagnet for attracting and holding a work by magnetic attraction. 2. Description of the Related Art Conventionally, this type of electromagnet is constructed by winding a coil 102 around a core 101 as shown in FIG.
The work 200 is attracted and held by magnetic attraction generated in the core 101 by energizing the coil 102. However, according to the above-described conventional electromagnet 100, the electromagnet 100 is brought close to the fixed work 200, or the work 200 is brought close to the fixed electromagnet 100. Therefore, there is a problem that high positioning accuracy is required for the means for moving the electromagnet 100 or the work 200 as described above. Therefore, in the electromagnet according to the first aspect of the present invention, the core is made movable so that the core can reliably attract and hold the work even if the positioning accuracy of the moving means is relatively low. The purpose is to. According to the electromagnet of the present invention, in addition to the purpose of the electromagnet of the above-mentioned claim, the work can be stabilized by adsorbing and holding the work at a plurality of positions equidistant from each other in the circumferential direction. The purpose is to hold. In order to solve the above-mentioned problems, an electromagnet of the present invention uses a case made of a magnetic material as a case.
Cylindrical non-magnetic with an opening to allow insertion inside
A case made of a body, and the periphery of the workpiece in the opening.
Coils are wound at equal intervals
A plurality of cores, and a peripheral wall of the case and each of the cores.
An elastic body that connects between and expands and contracts in the radial direction of the work
A state in which the work is inserted into and fixed to the opening.
When the coils are energized at, the magnetic attraction forces
The core draws on the work while extending the elastic body
The work is suction-held in a circumferential direction of the work . According to the electromagnet of the first aspect,
Since the core is movable, the core is attracted to the work even when the core and the work are not in contact with each other, and the core can reliably attract and hold the work. Therefore, even if the means for moving the work or the electromagnet has low positioning accuracy, the work can be reliably attracted and held. Further, according to the electromagnet of the second aspect,
Further, since the work is sucked and held at a plurality of positions equidistant from each other in the circumferential direction, the work can be stably held. An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 3, the electromagnet according to this embodiment selects a required work 60 from a plurality of works 60 such as tools arranged at a predetermined position P1 of an NC machine 50 in an NC system, for example. The present invention relates to the electromagnet 1 which is attached to the arm 71 of the robot 70 when it is attached to another predetermined position P2 and is used to transport the workpiece 60 to the position P2 while attracting and holding the workpiece 60. FIGS. 1 and 2 show an electromagnet 1 according to a first embodiment. FIG. 1 corresponds to a non-energized state, and FIG. 2 corresponds to an energized state. 1 and 2, the electromagnet 1 comprises a case 2, a plurality of sets, for example, four sets of coils 3 and cores 4, and a plurality of elastic members 5 connecting each core 4 and the case 2. ing. The case 2 is formed in a cylindrical shape having an opening 2a through which a work 60 made of a magnetic material can be inserted into the case 2, and is made of a non-magnetic material (for example, a synthetic resin material). Each core 4 is made of a magnetic material having an E-shaped cross section, and has a plurality of legs 4a, 4a along the axial direction of the work 60.
b, 4c, and the coil 3 is wound around a predetermined leg, for example, a center leg 4b. Each core 4 is provided with a work 60.
Are arranged at equal intervals in the circumferential direction. The elastic body 5 is made of rubber, a spring, an air damper, or the like, and connects between the peripheral wall 2b of the case 2 and each core 4 so as to be able to expand and contract in the radial direction of the work 60. When no power is supplied, as shown in FIG. 1, each elastic body 5 is in a normal state (a contracted state). Therefore, each core 4 is located near the peripheral wall 2b of the case 2 and retreats. In state. In this state, the work 60 is inserted into and fixed to the opening 2a of the case 2 and the coil 3 is energized.
A magnetic circuit is formed as shown by the two-dot chain line arrow, and a magnetic attraction force is generated between each core 4 and the work 60. , And move forward to be sucked. During energization, a magnetic circuit having a large magnetic flux density is formed as shown by a two-dot chain line arrow in FIG.
The work 60 is moved by the large magnetic attraction force to the leg end surface 4 of each core 4.
Adsorbed and held by d, 4e, 4f. In this state, the workpiece 60 is transported by moving the electromagnet 1. When the energization is stopped after the work 60 is conveyed, the magnetic attractive force disappears, and each core 4 retreats by the restoring force of the elastic body 5 and returns to its original position. As described above, since each core 4 is movable, the work 60 can be reliably attracted and held without making each core 4 abut on the fixed work 60.
Further, the present invention is not limited to the work 60 having a single diameter, and can be applied to works 60 having various diameters as long as the amount of extension of the elastic body 5 is limited. In addition, since the work 60 is suctioned and held at a plurality of positions equidistant from each other in the circumferential direction,
The work 60 can be stably held. FIGS. 4 and 5 show an electromagnet 1 according to another embodiment. FIG. 3 corresponds to a non-energized state, and FIG. 4 corresponds to an energized state. The electromagnet 1 shown in FIG. 4 and FIG.
Is formed in a bobbin shape, and the coil 3 is wound around the shaft portion 4g of the core 4. The other configuration and operation are as follows.
This is the same as the embodiment described above. Therefore, according to the electromagnet 1 of this embodiment, similarly to the above-described embodiment, the work 60 can be reliably attracted and stably held. FIGS. 6 and 7 show an electromagnet 1 according to still another embodiment, wherein FIG. 6 corresponds to a non-energized state and FIG. 7 corresponds to an energized state. The electromagnet 1 shown in FIGS. 6 and 7 has legs 4a, 4b, 4b, 4c of each core 4 of the electromagnet 1 shown in FIGS.
The end faces 4d, 4e, and 4f of 4c are characterized by having a curved surface shape corresponding to the outer peripheral surface shape of the work 60, and other configurations and operations are the same as those of the embodiment shown in FIGS. . Therefore, according to the electromagnet 1 of this embodiment, similarly to the above-described embodiments, the work 60 can be surely attracted and stably held and held. Since the outer peripheral surface of the 60 can be brought into surface contact, the magnetic flux density increases, and the magnetic attraction force further increases. The electromagnet 1 of the present embodiment is not limited to the work 60 having a circular cross section as described above, but can be sufficiently applied to a work 60 having a polygonal cross section or an ellipse. It is.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a configuration of an electromagnet according to one embodiment when power is not supplied. FIG. 1 (A) is a sectional view taken along line AA of FIG. 1 (B), and FIG.
Fig. 1 (A) is a sectional view taken along the line BB of Fig. 1 [Fig. 2] Fig. 2 shows a configuration of the same electromagnet when energized.
FIG. 2 (B) is a sectional view taken along the line AA in FIG. 2, and FIG. 2 (B) is a sectional view taken along the line BB in FIG. 2 (A). FIG. 4A is a cross-sectional view taken along the line AA of FIG. 4B, and FIG.
Fig. 4 (A) is a sectional view taken along the line BB of Fig. 5; Fig. 5 shows a configuration of the same electromagnet when energized;
5 (B) is a sectional view taken along the line AA in FIG. 5, and FIG. 5 (B) is a sectional view taken along the line BB in FIG. 5 (A). FIG. 6A is a sectional view taken along line AA of FIG.
6B is a sectional view taken along the line BB of FIG. 6A. FIG. 7 shows a configuration of the electromagnet when energized, and FIG.
FIG. 7 (B) is a sectional view taken along the line AA shown in FIG. 7, and FIG. 7 (B) is a sectional view taken along the line BB shown in FIG. 7 (A). FIG. 8 is a sectional view of a conventional electromagnet. 2a Opening 2b Peripheral wall 3 Coil 4 Core 5 Elastic body 60 Work

Claims (1)

(57) [Claims] [Claim 1] A work made of a magnetic material is inserted into the case.
It is made of a cylindrical non-magnetic material with an opening that allows
And the case is equidistant from each other in the circumferential direction of the work in the opening.
A plurality of cores wound around a coil and connected between the peripheral wall of the case and each of the cores,
An elastic body that can expand and contract in the radial direction of the workpiece, and the workpiece is inserted and fixed in the opening.
When the coils are energized at, the magnetic attraction forces
The core draws on the work while extending the elastic body
An electromagnet characterized in that the work is attracted and held in a circumferential direction of the work .