JP2023180493A - Workpiece holding device - Google Patents

Abstract

To hold a workpiece with high holding force.SOLUTION: A workpiece holding device 10 is a workpiece holding device for holding a plurality of workpieces W, and includes a plurality of magnets 11 for generating magnetic force for holding the plurality of workpieces W, and a magnet holding member 12 for holding the plurality of magnets 11 at an interval along a lateral direction at a position below the plurality of workpiece W. The respective plurality of magnets 11 are arranged so that S poles and N poles are aligned in the lateral direction, and the two adjacent magnets among the plurality of magnets 11 are arranged so that same poles of the two adjacent magnets face each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to a work holding device that holds one or more work pieces using magnetic force.

Workpieces subjected to laser welding, seam welding, etc. may be held by magnetic force during processing such as welding. Patent Document 1 discloses a technique in which a plurality of workpieces are each held by a plurality of magnets.

Japanese Patent Application Publication No. 2007-313543

In the technique described in Patent Document 1, a plurality of magnets are arranged so that different polarities face each other, but the inventor of the present invention discovered an arrangement of magnets that has a higher holding force for a workpiece than such an arrangement. Ta.

The present invention has been made in view of the above points, and an object of the present invention is to hold a workpiece with high holding force.

In order to solve the above problems, a work holding device according to the present invention is a work holding device that holds one or more workpieces, and includes a plurality of first magnets that generate magnetic force for holding the one or more workpieces. a magnet, and a magnet holding member that holds the plurality of first magnets at a position below the one or more workpieces at intervals along the left-right direction, each of the plurality of first magnets , S poles and N poles are arranged in a line along the left-right direction, and two adjacent magnets among the plurality of magnets have the same poles facing each other.

As an example, the magnet holding member includes a plurality of second magnets, and the plurality of second magnets are arranged at intervals along the front-back direction from each of the plurality of first magnets, and the plurality of second magnets are arranged at intervals along the front-rear direction, and Each of the second magnets is arranged with an S pole and an N pole aligned along the left-right direction, and a first magnet adjacent to the plurality of second magnets and the plurality of first magnets in the front-back direction In each combination of a magnet and a second magnet, the same poles face each other in the front-rear direction.

As an example, the plurality of first magnets have a non-perfect circular shape in plan view, the magnet holding member includes a plurality of recesses each accommodating the plurality of first magnets, and each of the plurality of recesses is , is formed in a shape that restricts the rotation of each of the plurality of first magnets accommodated therein.

As an example, the plurality of first magnets and the plurality of recesses are formed in a rectangular shape in plan view.

As an example, the magnet holding member includes a magnetic plate disposed below the plurality of first magnets, and the plurality of first magnets are held by the magnet holding member by adsorbing the magnetic plate. There is.

As an example, in each of the plurality of first magnets, an upper portion and a lower portion have an S pole and an N pole arranged on opposite sides.

As an example, in each of the plurality of first magnets, the S pole and the N pole of the upper and lower parts are arranged on the same side.

As an example, the one or more works are a plurality of works, and the work holding device further includes a tray arranged on the magnet holding member and having a plurality of recesses in which the plurality of works are respectively arranged. , the plurality of recesses are arranged so as to be located directly above the plurality of first magnets, respectively, when the tray is arranged on the magnet holding member.

According to the present invention, a workpiece is held with high holding force.

FIG. 1 is a plan view of a work holding device according to an embodiment of the present invention, with a tray partially cut away. FIG. 2 is an exploded cross-sectional view taken along the line AA in FIG. FIG. 3 is an enlarged sectional view showing a part of the AA cross section in FIG. FIG. 4 is a diagram showing part of the magnetic lines of force of a magnet in a comparative example. FIG. 5 is a diagram showing a part of the magnetic lines of force of the magnet in the workpiece holding device of FIG. 1. FIG. 6 is an enlarged sectional view of a work holding device in a modified example.

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, only some of the elements are labeled. Although the vertical direction and the front, rear, left, and right directions of the drawings do not necessarily match the actual vertical direction and horizontal direction, in this embodiment, they both match. In other words, the bottom side is the ground side, and the top side is the sky side. The left-right direction and the front-back direction may be arbitrary directions that are orthogonal to the up-down direction and orthogonal to each other. In FIGS. 2 and 3, which are cross-sectional views, a workpiece W and a magnet 11, which will be described later, are depicted in elevation. In the following description, plan view refers to the case viewed from above.

A workpiece holding device 10 according to the present embodiment shown in FIGS. 1 to 3 is configured as a stage of a seam welding device 1, and is configured to magnetically hold a plurality of workpieces W to be parallel seam welded by the seam welding device 1. has been done.

The workpiece W includes a package W1 containing electronic components (not shown) such as a crystal, and a lid W2 that closes an opening of the package W1. The seam welding apparatus 1 performs parallel seam welding on four sides of the upper surface of the workpiece W, that is, the upper surface of the lid W2, two opposing sides each, using a pair of roller electrodes E1 and E2. The lid W2 before parallel seam welding may be temporarily fixed to the package W1. The workpiece W includes a ferromagnetic material. For example, the package W1 and/or the lid W2 are ferromagnetic. Examples of the ferromagnetic material include pure iron, ferritic steel (SUS430, etc.) (hereinafter, the same applies to the ferromagnetic material).

The workpiece holding device 10 includes a plurality of magnets 11, a magnet holding member 12 that holds the plurality of magnets 11, a base 13 that supports the magnet holding member 12, and a plurality of workpieces W placed on the magnet holding member 12. and a tray 14 disposed above.

Each magnet 11 generates a magnetic force for attracting a workpiece W on the tray 14 placed directly above it, that is, a magnetic force for holding the workpiece W, as will be described later. Each magnet 11 is formed into a rectangular parallelepiped shape, and is formed into a rectangular shape when viewed from above. Each magnet 11 is magnetized so that the upper and lower parts have opposite north and south poles. The orientation of the magnet 11 will be described later.

The magnet holding member 12 includes a non-magnetic grid plate 12A and a ferromagnetic magnetic plate 12B. Examples of the non-magnetic material include an aluminum plate or an austenitic steel plate (SUS304, etc.) (hereinafter, the same applies to non-magnetic materials).

The lattice plate 12A has a lattice shape by including a plurality of through holes 12AA arranged in a matrix in a plan view.

The magnetic plate 12B is fixed to the lower surface of the lattice plate 12A with a plurality of bolts B1. The magnetic plate 12B may be fixed to the grid plate 12A by thermocompression bonding or the like. The magnetic plate 12B fixed to the grid plate 12A closes the lower opening of each of the plurality of through holes 12AA. As a result, the magnet holding member 12 is formed with a plurality of recesses 12R arranged in a matrix in a plan view.

A plurality of magnets 11 are accommodated in the plurality of recesses 12R, respectively. That is, one magnet 11 is accommodated in one recess 12R. Thereby, the magnets 11 are arranged at intervals in a matrix in a plan view. Each magnet 11 is magnetically attracted (that is, stuck) to the magnetic plate 12B forming the bottom of each recess 12R. Thereby, each magnet 11 is positioned and held within the recess 12R in which it is housed, and is suppressed from popping out from the recess 12R.

The grating plate 12A is made of a non-magnetic material as described above. This prevents the magnet 11 from being attracted to the grid plate 12A when the magnet 11 is inserted into the recess 12R. Thereby, for example, the magnet 11 can be easily inserted into the recess 12R without being obstructed by the lattice plate 12A.

The base 13 reinforces and supports the magnet holding member 12. The base 13 is fixed to the magnet holding member 12 with bolts B2. The base 13 is supported by a stage support mechanism (not shown) of the seam welding apparatus 1.

The tray 14 includes a plurality of recesses 14R arranged at intervals in a matrix in a plan view. A plurality of workpieces W are respectively placed in the plurality of recesses 14R. In other words, one workpiece W is placed in one recess 14R. As a result, each workpiece W is placed on the tray 14 in a positioned manner. The tray 14 includes a lattice plate 14A having a plurality of through holes 14AA each forming a plurality of recesses 14R, and a plate-shaped base that is fixed to the lower surface of the lattice plate 14A by thermocompression bonding or the like and closes the plurality of through holes 14AA from below. A member 14B is provided. The tray 14 is made of a non-magnetic material so that the work W can be easily taken out from the tray 14.

The workpiece W is transported to the seam welding device 1 or transported from the seam welding device 1 after welding with the tray 14 as a whole. For this reason, the tray 14 is provided in a detachable manner with respect to the magnet holding member 12. The tray 14 is positioned at a predetermined position on the magnet holding member 12 by an uneven structure or a rail member (not shown).

Each recess 14R of the tray 14 disposed on the magnet holding member 12 is arranged directly above each recess 12R of the magnet holding member 12, respectively. Thereby, each work W accommodated in each recess R2 is located directly above each magnet 11 respectively accommodated in each recess R1. In other words, one workpiece W is located directly above one magnet 11 .

Each workpiece W is attracted downward by the magnetic force of the magnet 11 located directly below the workpiece W, thereby suppressing the positional shift of the workpiece W, particularly the protrusion from the recess 14R of the tray 14. In this way, the workpiece W is held by the magnetic force generated by the magnet 11.

In this embodiment, each of the magnets 11 held by the magnet holding member 12 at a position below each workpiece W at intervals along the left-right direction is oriented such that the north pole and the south pole are aligned in the left-right direction. It is located in The two magnets 11 adjacent to each other in the left and right direction are arranged so that the same poles face each other. Rather than arranging two magnets 11 adjacent in the left and right direction so that different polarities face each other (for example, as in Patent Document 1 above), the inventor of the present invention has arranged two magnets 11 that are adjacent to each other in the left and right direction so that the same polarities face each other as in the present embodiment. It has been found that the holding force of each workpiece W by each magnet 11 (represented by the minimum force required to displace the workpiece W) is improved by arranging the magnets 11 in this manner. Specifically, the holding force of the latter was about 1.2 times that of the former. Although this principle is not certain, it is assumed as follows. That is, when different poles face each other, a portion of the lines of magnetic force from the north pole of one magnet 11 goes toward the south pole of the other magnet 11 (see FIG. 4). However, when the same poles face each other, some of the lines of magnetic force head toward the workpiece W, resulting in an increase in the number of lines of magnetic force that head toward the workpiece W (see FIG. 5). This increases the density of the lines of magnetic force acting on the workpiece W, and the workpiece W is attracted to the magnet 11 with a correspondingly stronger force. As described above, in this embodiment, since the two magnets 11 adjacent to each other in the left and right direction are arranged so that the same poles face each other, each workpiece W is held with a high holding force.

As shown in FIG. 1, in this embodiment, sets of magnets 11 lined up along the left-right direction are lined up in the front-back direction, so that a plurality of magnets 11 are arranged in a matrix. In other words, the plurality of magnets 11 include a plurality of magnets 11 (first magnets) arranged at intervals along the left-right direction, and a plurality of magnets 11 (second magnets) arranged at intervals along the front-rear direction. )including. The two magnets 11 adjacent to each other in the front-back direction have the same polarity facing each other in the front-back direction. With such a configuration, the density of the magnetic lines of force acting on the workpiece W can be made higher than when different poles face each other in the front-rear direction, based on the same principle as the above assumption, and as a result, each workpiece W is held with a high holding force.

As described above, each two adjacent magnets 11 have the same polarity facing each other, so they repel each other. Due to this repulsion, each magnet 11 tries to rotate. However, in this embodiment, as shown in FIG. 1, the magnet 11 and the recess 12R are formed into the same square shape in plan view. Therefore, the magnet 11 attempting to rotate hits the inner wall of the recess 12R, that is, the inner wall of the through hole 12AA, thereby preventing the magnet 11 from rotating. This prevents the different polarities of two adjacent magnets 11 from facing each other due to the rotation of the magnets 11, which prevents the holding force of the workpiece W from decreasing.

Although the shape of each magnet 11 and each recess 12R is arbitrary, a shape that can prevent rotation as described above is preferable. Therefore, each magnet 11 preferably has a non-perfect circular shape in plan view. Each recess 12R is preferably formed in a shape that restricts rotation of the magnet 11 accommodated therein. For example, the magnet 11 and the recess 12R may have an elliptical shape or the like. The recess 12R may have any shape as long as its inner wall prevents the magnet 11 from rotating. Such a rotation regulating configuration is effective when the magnet 11 is held by the magnetic plate 12B by magnetic force as in the above embodiment. This is because when the magnet 11 is attracted to the magnetic plate 12B by magnetic force, the magnet 11 is likely to rotate due to repulsion with other magnets 11.

As in this embodiment, the plurality of magnets 11 are attracted to the magnetic plate 12B and held by the magnet holding member 12, so that tape ( (adhesive film) etc. can be omitted. The tape described above is for preventing the magnet 11 from popping out from the through hole 12AA, but by providing the magnetic plate 12B and omitting the tape, it is possible to prevent the magnet 11 from sticking to the top surface of the grid plate 12A. The magnet 11 can be brought closer to the workpiece W by the distance of the tape.

Furthermore, in this embodiment, by providing the tray 14 on which a plurality of works W are placed, each work W is placed at a suitable position for holding each work W by magnetic force (here, directly above each magnet 11). ) can be easily placed.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. For example, the present invention includes various modifications to the above embodiments that can be understood by those skilled in the art within the scope of the technical idea of the present invention. In particular, the shape of each element (member, component, etc.) constituting the workpiece holding device is arbitrary and can be changed as appropriate. Other modified examples will be illustrated below, but each modified example may be combined.

The tray 14 may be prepared as a separate member from the work holding device 10. In other words, the work holding device 10 does not need to include the tray 14.

One magnet 11 may be configured to attract a plurality of works W. That is, the magnet 11 may be larger than the workpiece W in plan view. In this case, for example, by arranging a plurality of works W at the ends of the S and N poles of the magnet 11, the works W are arranged in areas with a large magnetic force. A plurality of magnets 11 may be used for one workpiece W. Further, in the above embodiment, the workpiece W and the magnet 11 have the same shape in plan view, but they may have different shapes. In particular, the workpiece W may be larger than the magnet 11 in plan view. The plurality of magnets 11 may be arranged in a row in the left-right direction instead of in a matrix.

Instead of the magnet 11, a magnet 111 may be used, as shown in FIG. 6, in which the upper and lower parts have the S pole and the N pole arranged on the same side. Since such a magnet 111 is more easily formed than the magnet 11, manufacturing costs can be reduced. In addition, in the case of a structure in which the S pole and the N pole are arranged on opposite sides in the upper and lower parts as in the above embodiment, lines of magnetic force are generated from the N pole in the upper part to the S pole in the lower part, but as shown in FIG. In the case of such a structure, the lines of magnetic force can be directed toward the workpiece W or the magnetic plate 12B, and it is considered that the holding force of the workpiece W or the magnet 11 can be made larger than in the above embodiment.

The magnet 11 may be fixed to the base 13 or the like using double-sided tape instead of the magnetic plate 12B, but double-sided tape is also weak against the rotation of the magnet 11, so even with these configurations, it is not possible to restrict the rotation. It would be good if it were adopted. Instead of or in addition to the magnetic plate 12B, tape may be applied to the upper and/or lower surfaces of the grid plate 12A to physically prevent the magnets 11 from popping out from the through holes 12AA.

The present invention is applicable to devices other than seam welding, and the workpiece held by the magnet or workpiece holding device may be a workpiece sealed in various packages including laser welding, or by other methods. It may also be a workpiece processed by.

DESCRIPTION OF SYMBOLS 1... Seam welding device, 10... Work holding device, 11... Magnet, 12... Magnet holding member, 12A... Grid plate, 12AA... Through hole, 12B... Magnetic plate, 12R... Recessed part, 13... Base, 14... Tray, 14A ...Lattice plate, 14AA...Through hole, 14B...Base member, 14R...Recess, 111...Magnet.

Claims (8)

A work holding device that holds one or more workpieces,
a plurality of first magnets that generate magnetic force for holding the one or more workpieces;
a magnet holding member that holds the plurality of first magnets at intervals along the left-right direction at a position below the one or more workpieces;
Each of the plurality of first magnets is arranged with an S pole and an N pole aligned along the left-right direction,
Two adjacent magnets among the plurality of magnets have the same polarity facing each other,
Work holding device. The magnet holding member includes a plurality of second magnets,
The plurality of second magnets are arranged at intervals from each of the plurality of first magnets in the front-rear direction,
Each of the plurality of second magnets is arranged with an S pole and an N pole aligned along the left-right direction,
In each combination of the plurality of second magnets and the plurality of first magnets, first magnets and second magnets adjacent in the front-rear direction, the same poles face each other in the front-rear direction,
The work holding device according to claim 1. The plurality of first magnets have a non-perfect circular shape in plan view,
The magnet holding member includes a plurality of recesses each accommodating the plurality of first magnets,
Each of the plurality of recesses is formed in a shape that restricts rotation of each of the plurality of first magnets accommodated therein.
The work holding device according to claim 1. The plurality of first magnets and the plurality of recesses are formed in a rectangular shape in a plan view.
The work holding device according to claim 3. The magnet holding member includes a magnetic plate disposed below the plurality of first magnets,
The plurality of first magnets are held by the magnet holding member by adsorbing the magnetic plate,
The work holding device according to claim 1. Each of the plurality of first magnets has an S pole and a N pole arranged on opposite sides at an upper part and a lower part,
The work holding device according to any one of claims 1 to 5. Each of the plurality of first magnets has an upper part and a lower part with an S pole and an N pole arranged on the same side,
The work holding device according to any one of claims 1 to 5. The one or more works are a plurality of works,
further comprising a tray disposed on the magnet holding member and having a plurality of recesses in which the plurality of works are respectively arranged;
The plurality of recesses are arranged so as to be respectively located directly above the plurality of first magnets when the tray is arranged on the magnet holding member.
The work holding device according to any one of claims 1 to 5.

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