JP2002374096A - Electronic component mounting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size while increasing the thrust and enhancing the controllability. SOLUTION: An electronic component mounting apparatus comprises an X direction linear motor 14 and a Y direction linear motor 12 of the same structure wherein hollow moving coils 2 are arranged in the moving direction while aligning the direction of flux being excited by a drive current with the moving direction, an upper side yoke 3 and a lower side yoke 4 are arranged to extend in the moving direction while holding the plurality of hollow moving coils 2 between, a center yoke 5 is inserted into the hollow section of the hollow moving coils 2 to extend in the moving direction, permanent magnets 6 are arranged in the moving direction on the surface of the upper and lower side yokes 3 and 4 on the hollow moving coil 2 side to form a field flux, and a component attraction head 7 is integrated with the hollow moving coils 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component mounting apparatus using a phase drive linear motor.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand for labor saving in a printed circuit board mounting process. Technology development on surface mounting has been strongly promoted to meet this demand. An electronic component mounting device (commonly known as a chip mounter) is used for surface mounting of a printed circuit board. In order to reduce the size and speed of the electronic component mounting device, a phase drive linear motor is employed in the head drive device. A phase drive linear motor employed in such a conventional electronic component mounting apparatus will be described with reference to the drawings.

FIG. 8 is a configuration diagram of a conventional linear motor for an electronic component mounting apparatus. 8, a conventional linear motor 101 for an electronic component mounting apparatus has a U-shaped yoke 104 including an upper side yoke 102 and a lower side yoke 103,
A hollow moving coil 106 fixed to both surfaces of a moving body mounting portion 108 together with a reinforcing plate 105, and permanent magnets arranged side by side on the surfaces of the upper side yoke 102 and the lower side yoke 103 on the side of the hollow moving coil to form a field magnetic flux. 107
And

The U-shaped yoke 104 guides the movement of the hollow moving coil 106 (in the direction of arrow A in the figure). The upper side yoke 102 and the lower side yoke 10
3 has a hollow moving coil 106 on its side.
The permanent magnet 107 is arranged in the moving direction. The polarity is such that the permanent magnet 107 on the upper side yoke 102 side and the permanent magnet 107 on the lower side yoke 103 side at the corresponding positions when viewed in the arrow direction A have their magnetic poles directed in the same direction. I have.

Further, all the permanent magnets 107 adjacent to each other as viewed in the arrow direction A have their magnetic poles directed in opposite directions. The permanent magnet 107 generates a field magnetic flux of the linear motor. The hollow moving coil 106 is a moving element of a linear motor that is driven in the arrow direction A by the field magnetic flux when a driving current is applied. The configuration of the hollow moving coil 106 will be described in detail with reference to the drawings.

FIG. 9 is a sectional view of a conventional linear motor for an electronic component mounting apparatus. As shown in FIG. 9, the hollow moving coil 106 is a flat coil and is fixed to both surfaces of the moving body mounting portion 108 together with the reinforcing plate 105. In the hollow moving coil 106, the magnetic flux excited by the drive current matches the direction of the field magnetic flux generated by the permanent magnet 107. Next, the structure of the hollow moving coil 106 will be described in detail.

FIG. 10 is an explanatory view of a hollow moving coil. As shown in FIG. 10, the hollow moving coil 106 has a predetermined interval K1 in the arrow direction A with the reinforcing plate 105 interposed therebetween.
Placed away. The hollow moving coil 106 is formed by wet winding. The wet winding is a winding method in which an epoxy resin or the like is penetrated between the windings in which the windings are wound to form a predetermined coil shape, and the coil is fixed while maintaining the coil shape.

Since the hollow moving coil 106 has a flat shape, a reinforcing plate 105 is used to reinforce the strength in the vertical direction. Further, a convex portion 110 is provided for positioning the hollow moving coil 106. Further, the reinforcing plate 10
A hollow D2 having a depth equal to the thickness D1 of the coil is provided so that when the hollow moving coil 106 is inserted into the hole 5, no unevenness is formed on the horizontal plane of the hollow moving coil 106 aligned as a whole.

As described above, the hollow moving coil 106 used in the conventional linear motor for the electronic component mounting apparatus is used.
Is a flat coil. Further, the magnetic flux excited by the driving current matches the direction of the field magnetic flux generated by the permanent magnet 107. In this state, they are arranged in alignment in the arrow direction A. The following describes what problems the conventional electronic component mounting apparatus employing the linear motor having such a configuration has to solve.

[0010]

The above prior arts have the following problems to be solved. Problem 1 As shown in FIG. 10, in the hollow moving coil 106, since the L1 portion (usually about 8 mm) does not contribute to the generation of thrust of the linear motor, the utilization efficiency of the winding is deteriorated. As a result, in order to obtain a desired thrust, the volume of the coil increases, and as a result, the size of the electronic component mounting apparatus increases.

Problem 2 As described above, since the hollow moving coil 106 has a flat shape, the reinforcing plate 105 is required to reinforce the strength in the vertical direction. Since the reinforcing plate 105 is a non-magnetic material, the magnetic resistance is large and the field magnetic flux is weakened, so that the efficiency is reduced.
As a result, in order to obtain a desired thrust, the volume of the coil increases, and as a result, the size of the electronic component mounting apparatus increases.

Problem 3 Since the direction of the magnetic flux generated by the drive current applied to the hollow moving coil 106 matches the direction of the field magnetic flux, the field magnetic flux is disturbed. That is, a phenomenon similar to the armature reaction in the rotating device occurs, the linearity of the current to the thrust is deteriorated, the controllability is deteriorated, and sometimes vibration occurs. As a result, the controllability of the electronic component mounting device deteriorates.

Problem 4 Since the leakage magnetic flux caused by the hollow moving coil 106 is large, an eddy current is generated in the U-shaped yoke 104 (FIG. 8), and the temperature of the device is increased. As a result, the magnetomotive force of the permanent magnet 107 (FIG. 1) is weakened, the field magnetic flux is reduced, and the thrust of the electronic component mounting device is reduced.

Since the four problems described above have not been solved, the conventional electronic component mounting apparatus has to be large in size, small in thrust, and poor in controllability. The present invention solves the above-mentioned problems and reduces the size of an electronic component mounting device,
The purpose is to achieve high thrust and high controllability.

[0015]

The present invention employs the following structure to solve the above problems. <Structure 1> A component suction head that sucks an electronic component and mounts it on a substrate, an X-direction moving body to which the component suction head is fixed, and an X-direction that supports and drives the X-direction moving body so as to be movable in the X direction. An electronic component mounting device comprising a linear motor, a Y-direction moving body to which the X-direction linear motor is fixed, and a pair of Y-direction moving means for supporting and driving the Y-direction moving body so as to be movable in the Y direction. The X-direction linear motor includes an upper side yoke and a lower side yoke in each of which a plurality of permanent magnets are arranged, a center yoke interposed between the upper side yoke and the lower side yoke, The permanent magnet includes a hollow coil member that is movably wound around the yoke and that is arranged side by side in the longitudinal direction of the center yoke and that fixes the X-direction moving body. The permanent magnets on the upper side yoke side and the permanent magnets on the lower side yoke side, each of which opposes the magnetic poles, are arranged in opposite directions, and the permanent magnets adjacent to each other along the longitudinal direction of the center yoke have magnetic poles. An electronic component mounting device, wherein the electronic component mounting device is a linear motor in which are arranged in opposite directions.

<Structure 2> In the structure 1, the Y-direction moving means may be provided between an upper side yoke and a lower side yoke in each of which a plurality of permanent magnets are arranged, and the upper side yoke and the lower side yoke. An intervening center yoke, a hollow coil member that is movably wound around the center yoke and arranged side by side in the longitudinal direction of the center yoke, and that fixes the Y-direction moving body;
The permanent magnets are arranged so that their magnetic poles are opposed to each other in the upper side yoke side permanent magnet and the lower side yoke side permanent magnet facing each other, and are adjacent along the longitudinal direction of the center yoke. An electronic component mounting device, wherein the magnets are linear motors in which magnetic poles are arranged in opposite directions.

<Structure 3> In the electronic component mounting apparatus according to any one of Structures 1 and 2, the permanent magnet 4N (N is an integer) arranged along the moving direction of the coil member of the linear motor as a set. When the position angle in the direction is set to 4π, the length of the coil member in the moving direction as a set of a plurality of the coil members is set to be equal to the position angle 4π. apparatus.

<Structure 4> In the electronic component mounting apparatus according to any one of Structures 1 to 3, the linear motor includes a permanent magnet set at a position angle of 4π and a set of four linear motors. And a coil member set to a length equal to the position angle 4π. The set of six coil members includes a three-phase AC U-phase, -U
An electronic component mounting apparatus to which a phase, a W phase, a -W phase, a V phase, and a -V phase are respectively applied.

<Structure 5> In the electronic component mounting apparatus according to any one of structures 1 to 4, the magnetic poles may be arranged in the moving direction between all the permanent magnets adjacent to each other in the moving direction of the coil member of the linear motor. An electronic component mounting device, wherein auxiliary magnets oriented in mutually opposite directions are arranged.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below using specific examples. <Structure of Specific Example> FIG. 1 is a view showing the structure of a linear motor used in the present invention. As shown in FIG. 1, a linear motor 1 used in the present invention includes a hollow moving coil (coil member) 2, an upper side yoke 3, a lower side yoke 4, a center yoke 5, a permanent magnet 6, a yoke 8, and a moving body mounting portion 9. Is provided.

Prior to the detailed description of the linear motor 1 used in the present invention, an electronic component mounting apparatus of the present invention using the linear motor 1 will be described. FIG.
It is an explanatory view of an electronic parts mounting device of the present invention. The electronic component mounting apparatus 11 according to the present invention includes a component suction head 7 for vacuum mounting a component (not shown) and mounting the component on a printed circuit board.
For positioning the component suction head 7 in the Y direction.
Direction linear motor 12 and this Y direction linear motor 12
Support beams 13 for supporting the components, and the component suction head 7
An X-direction linear motor 14 for positioning in the X-direction, an X-direction moving body 17 for fixing the component suction head 7, and a Y-direction moving body 18 for fixing the X-direction linear motor 14.

Further, the Y-direction linear motor may be a mechanism in which a linear guide is added to a known combination of a servo motor and a belt or a combination of a servo motor and a ball screw as an alternative means.

The electronic component mounting apparatus head driving device 11 is mounted on a base 15 to constitute an electronic component mounting apparatus. Although not shown, the electronic component mounting apparatus is provided with a suction nozzle that supports the component suction head 7 in a rotatable and vertically movable manner, and performs suction of the mounted component and mounting on the substrate. Further, a mounting component supply unit for storing a plurality of types of mounting components, a conveyor for transporting a printed circuit board, and the like are provided.

A printed board (not shown) is transported to a predetermined position on the upper surface of the base 15 by a conveyor (not shown). An electronic component mounting apparatus according to the present invention drives an X-direction linear motor 14 and a Y-direction linear motor 12 to drive a component suction head 7 from a mounting component supply unit (not shown).
Vacuum-adsorbs the mounted parts. Further, the X-direction linear motor 14 and the Y-direction linear motor 12 are driven to move to a predetermined position on the printed circuit board to mount the mounting component.

The support beams 13 are provided on both ends of the upper surface of the base 15 so as to straddle the conveyor in a direction perpendicular to the conveying direction (X direction) of the conveyor (not shown). The upper surfaces of the two support beams 13 are adjusted horizontally so that the upper surfaces of the respective support beams 13 fall within the same plane. On the upper surface of the support beam 13, Y
A directional linear motor 12 is mounted. On the Y-direction linear motor 12, an X-direction linear motor 14 on which the component suction head 7 is mounted is mounted on and supported by a Y-direction moving body 18.

That is, the component suction head 7 is positioned in the Y direction by the Y-direction linear motor 12, and is further positioned in the X direction by the X-direction linear motor 14.
As a result, the component suction head 7 is positioned at a desired position on a printed board (not shown). The description of the electronic component mounting apparatus of the present invention has been completed.
The details of the configuration of the linear motor 1 used in the present invention will now be described.

The hollow moving coil 2 is a portion to which a drive current is applied by an external circuit (not shown). This is a portion that generates a thrust based on Fleming's left-hand rule by a linkage between a drive current and a field magnetic flux generated by a permanent magnet 6 described later. This will be described in detail with reference to the drawings.

FIG. 3 is an explanatory view of the hollow moving coil.
As shown in FIG. 3, the direction X of the magnetic flux excited by the drive current is an integral multiple of 3 (3 ×
N) coil members (3A1, 3A2, 3B1, 3B)
2, 3C1, 3C2) are fixed in a stacked state. This coil member (3A1, 3A2, 3B1, 3B
2, 3C1, 3C2) are formed by winding a winding such as an enameled wire in a multilayer manner with the hollow portion 23 provided. After forming a predetermined coil shape, an epoxy resin or the like is permeated between the windings, and is fixed while maintaining the coil shape. It is commonly called wet winding. The phase arrangement of the drive current will be described later with reference to the drawings together with the magnetic pole arrangement of the permanent magnet 6.

The points to be noted here are as follows.
As shown in FIG. 9, the conventional hollow moving coil 106 is a flat coil and is fixed to both surfaces of the moving body mounting portion 108 together with the reinforcing plate 105. In the hollow moving coil 106, the magnetic flux excited by the drive current matches the direction of the field magnetic flux generated by the permanent magnet 107. On the other hand, the hollow moving coil 2 used in the present invention makes the direction of the magnetic flux excited by the driving current coincide with its own moving direction (X direction), which will be described later, and is arranged in a stacked state in this moving direction. Are arranged.

Upper side yoke 3 and lower side yoke 4
Is a portion arranged with the hollow moving coil 2 interposed therebetween and extending in the moving direction (X direction). This is a portion that supports the hollow moving coil 2 together with a center yoke 5 described later. Upper side yoke 3 and lower side yoke 4
Inside (a surface on the side of the hollow moving coil 2), permanent magnets 6, which will be described later, are arranged side by side in the moving direction (X direction) of the hollow moving coil 2. The upper side yoke 3 and the lower side yoke 4 usually have a U-shaped yoke 8 having a U-shaped cross section.
It is integrated into. In the electronic component mounting apparatus 11 (FIG. 2) of the present invention, this yoke 8
(FIG. 2) or a portion expressed as an X-direction linear motor 14 (FIG. 2).

The center yoke 5 is inserted through a hollow portion 23 (FIG. 3) of the hollow moving coil 2 and supports the movement of the hollow moving coil 2 together with the upper side yoke 3 and the lower side yoke 4 to move the center moving yoke. This portion extends in the direction X.

The permanent magnet 6 is a permanent magnet that generates a field magnetic flux. The polarity arrangement of the permanent magnets 6 will be described with reference to the drawings. FIG. 4 is an explanatory diagram of the magnetic pole arrangement. As shown in FIG. 4, the permanent magnets 6 in the upper side yoke side 3 and the permanent magnets 6 in the lower side yoke side at the corresponding positions in the moving direction X have opposite magnetic poles. Is aimed at.

That is, the magnetic poles are arranged with their polarities reversed. Further, all the permanent magnets 6 adjacent in the moving direction X have their magnetic poles directed in opposite directions. In the linear motor used in the present invention, four permanent magnets 6
And six hollow moving coils 2 are configured as one set. The reason for this will be described later in detail in the description of the operation.

Further, the hollow moving coil 2 has a three-phase alternating current (U
It is configured to be able to perform synchronous driving in the order of (2/3) π in the plus direction in the order of phase, V phase, and W phase). The phase sequence of three-phase alternating current is different from the normal phase sequence,
Here, the U phase, the W phase, and the V phase are stored. The reason for this will be described later in detail in the section of the operation, because the phase difference of each phase is set to (4/3) π. As shown in FIG. 4, the coil member 3A1 has a + U phase, the coil member 3A2 has a -U phase,
+ W phase for coil member 3B1, -W for coil member 3B2
Phase, + V phase for coil member 3C1,-for coil member 3C2
V phase are supplied respectively.

The center yoke 5 is inserted through the hollow portion 23 (FIG. 3) of the hollow moving coil 2 and supports the movement of the hollow moving coil 2 together with the upper side yoke 3 and the lower side yoke 4 to move in the moving direction. It is a portion extending to X.
The moving body mounting part 9 is a part to which the component suction head 7 is mounted. As described above, the linear motor 1 used in the present invention
Now that the description of the configuration has been completed, the operation will be described.

<Operation of Specific Example> FIG. 5 is an explanatory view (part 1) of the operation principle of the linear motor. As described in FIG. 4, the linear motor used in the present invention includes four permanent magnets 6 and six coil members as operation units. Here, in order to explain the basic principle, four permanent magnets 6-2 to 6-5 (or 6-8 to 6-8) as shown in FIG.
6-11) and three coil members (3A1, 3B1, 3C1) that move together as one unit.

As shown in the figure, the magnetic flux output from the permanent magnet 6-3 passes through the center yoke 5 and
2, or input to the permanent magnets 6-2 to 6-4. Further, the magnetic flux output from the permanent magnet 6-9 passes through the center yoke 5 and passes through the permanent magnet 6-8 or
It is input to the permanent magnets 6-8 to 6-10.
Similarly, the magnetic flux output from the permanent magnet 6-5 is input to the permanent magnet 6-4 or the permanent magnets 6-4 to 6-6 via the center yoke 5. Further, the magnetic flux output from the permanent magnet 6-11 passes through the center yoke 5 and passes through the permanent magnet 6-10 or the permanent magnet 6-6.
10 to the permanent magnet 6-12.

A position angle (a magnetic field phase angle) is set with the left side of the permanent magnet 6-2 and the permanent magnet 6-8 as a starting point. The position angle is determined to advance by π for each adjacent permanent magnet in the magnetic pole direction. Further, x represents the moving distance of the three coil members (3A1, 3B1, 3C1) moving integrally from the left side of the permanent magnet 6-2 and the permanent magnet 6-8 in the right direction (X-axis direction). Determine.

When the coil member (3A1) moves in the X-axis direction by a distance x, the number of magnetic fluxes interlinked is represented by Ba = Bm · SIN (x) (1) The number of magnetic fluxes linked when the member (3B1) moves in the X-axis direction by the distance x is represented by Bb = Bm · SIN (x + 4π / 3) (Expression 2) The coil member (3C1) has the distance x The number of magnetic fluxes that interlink when moved in the X-axis direction is Bc = Bm · SIN (x + 8π / 3) (3) Here, Bm is the maximum magnetic flux density of the permanent magnet,
The displacement of each coil member is determined by the position angle (4π / 3, 8
π / 3).

As shown in FIG. 4, the coil member (3A
1, 3B1, 3C1) are supplied with the following drive currents, respectively. For the coil member (3A1), Ia = Im · SIN (ωT) (4) For the coil member (3B1), Ib = Im · SIN (ωT + 4π / 3) (Equation 5) The coil member (3C1) is supplied with a drive current expressed by Ic = Im · SIN (ωT + 8π / 3) (Equation 6). The points to be noted here are as follows. (Equation 4) is the U phase of the three-phase alternating current defined above, and (Equation 5) is the W phase. From equation (6), Ic = Im · SIN (ωT + 8π / 3) = Im · SIN
(ΩT + 2π / 3), and this equation becomes the V phase. In other words, this is equivalent to connecting the three-phase AC phases in the order of U-phase, W-phase, and V-phase.

From the equations (1) to (6) obtained above, the three magnetic field coils of the permanent magnets 6-1 to 6-6 intersect with the current flowing through the coil members to link the three coil members (3A1, 3A3).
B1, 3C1) is expressed by the following equation. F = Bm · SIN (x) × Im · SIN (ωT) + Bm · SIN (x + 4π / 3) × Im · SIN (ωT + 4π / 3) + Bm · SIN (x + 8π / 3) × Im · SIN (ωT + 8π / 3) = (1/2) Bm · Im [COS (ωT−x) −COS (ωT + x) + COS (ωT−x) −COS (ωT + x + 8π / 3) + COS (ωT−x) −COS (ωT + x + 16π / 3)] Since the sum of three AC signals having different phases by an integral multiple of (2/3) π becomes 0, COS (ωT + x) + COS (ωT + x + 8π / 3) + COS (ωT + x + 16π / 3) in parentheses in the above equation ) = 0 (7) Therefore, F = (3Bm · Im / 2) × COS (ωT−x) (8)

From equation (8), when (ωT−x) = 2Nπ (9), the maximum value is 3 · Bm · Im / 2. Here, N = 0, 1, 2, 3... Differentiating (Equation 9) with respect to time T, ω−dx / dT = 0. Therefore, the phase velocity dx / dT on the X-axis is: dx / dT = ω (Equation 10) ). (Equation 10) includes three movable coil members (3A1,
3B1, 3C1) moves in the X-axis direction at the phase velocity ω represented by the position angle, the coil members (3A1, 3B
1, 3C1) from the field magnetic flux is always constant. A point to be noted here is that, in order to satisfy the above (Equation 7) and (Equation 8), the amount of change in the position angle of the three coil members (3A1, 3B1, 3C1) (here, (4/3) π), and three coil members (3A1,
3B1 and 3C1), the phase difference (here, (4/3) π) of the drive current applied to each of them is required to be an integral multiple of (2/3) π. Or because it is a synchronous motor, ωT
= X is a precondition.

That is, a set of three coil members (3A1,
3B1 and 3C1) with the position angle as (4/3) π
When drive currents having different phases are applied to each of them at a distance of (4/3) π, three coil members (3A1, 3B1, 3A) are applied at a phase speed represented by the drive current angular frequency ω.
C1) moves. The permanent magnet 6-
1 to 6-6 field magnetic fluxes and three coil members (3A1, 3A3)
B1 and 3C1) are linked to each other
The thrust F acting on the coil members (3A1, 3B1, 3C1) has been described. In addition, three coil members (3A1,
3B1 and 3C1), the thrust F acts in the same direction by the linkage with the field magnetic flux of the permanent magnets 6-7 to 6-11.
The explanation is omitted because it is the same theory.

As described above, the four permanent magnets 6-1 to 6-
5 for three coil members (3A1, 3B1, 3C
1) operates as a set. Other combinations do not satisfy the above (Equation 7) and (Equation 8). This concludes the description of the basic principle of the linear motor used in the present invention, and then describes the operation principle of the embodiment.

FIG. 6 is a diagram (part 2) for explaining the operation principle of the linear motor. According to the basic operation principle, three coil members (3A1, 3B) having a position angle of 2π / 3 are used.
1, 3C1) were arranged at an interval of 4π / 3 from each other. In the embodiment, three coil members (3A2, 3B2, 3C2) having a position angle of 2π / 3 are arranged in the interval.

Further, as already described with reference to FIG. 4, the coil member 3A1 has a + U phase, the coil member 3A2 has a -U phase,
+ W phase for coil member 3B1, -W for coil member 3B2
Phase, + V phase for coil member 3C1,-for coil member 3C2
The V phases are respectively connected. Where -U phase, -W
The phase and the −V phase are the reverse connection of the + U phase, + W phase, and + V phase of the three-phase alternating current.

By employing such a connection, the phase of the drive current applied to the coil members (3A2, 3B2, 3C2) is delayed by 4π / 3 for each phase. On the other hand, the coil member (3A2, 3B2, 3C2) is
1, 3B1, 3C1), the position angles of the coil members are also shifted by 4π / 3 from each other. Therefore, the above (7)
Expression (8) is satisfied. As a result, the coil member (3A
1, 3B1, 3C1) also acts on the coil members (3A2, 3B2, 3C2).

That is, the linear motor of the embodiment has three coil members (3A1, 3B
1, 3C1) is equivalent to connecting two linear motors in series without increasing the volume. The purpose of adopting such a configuration is to reduce the leakage magnetic flux caused by the hollow moving coil 106 (FIG. 8) described in the above-mentioned problem 4, and
The purpose is to minimize the generation of eddy currents in the U-shaped yoke 104 (FIG. 8).

As shown in FIG. 6, the magnetic flux excited by the drive current I · SIN (ωT) of the coil member 3A1 is represented by H
A1, the driving current of coil member 3A2-I · SI
The magnetic flux excited by N (ωT) becomes HA2, and the direction of the magnetic flux is reversed and cancels each other. Similarly, the magnetic flux excited by the coil members 3B1 and 3B2 and the magnetic flux excited by the coil members 3C1 and 3C2 have the same result.

As a result, the directions of the leakage magnetic fluxes caused by the hollow moving coil 106 (FIG. 8) described in the above-mentioned problem 4 are reversed in the directions opposite to each other, and are canceled out.
The generation of eddy currents in FIG. 8 can be minimized. Further, magnetic saturation of the yoke 104 due to the magnetic flux of the hollow moving coil 106 can be prevented, and the thrust linearity and large thrust can be maintained. In the above description, six coil members (3A1, 3A2, 3B1, 3B) are provided for the four permanent magnets 6-1 to 6-5.
2, 3C13C2) has been described as a set. However, the invention is not limited to this example.

Satisfaction of the above equations (7) and (8) is not limited to the case where six coil members form one set for four permanent magnets. In order to satisfy both equations, it is only necessary that the amount of change in the phase angle of the drive current applied to the adjacent coil member is equal to the amount of change in the position angle of the coil member.

However, the sum of the drive currents applied to each of the plurality of coil members at this time must be zero as shown in the above (Equation 7). Also in this case, by appropriately setting the number of the plurality of coil members, the leakage magnetic flux can be reduced as described above. In the above description, the winding directions of all the six coil members are the same, and the driving current is + U
Phase, -U phase, + W phase, -W phase, + V phase, and -V phase. However, since the winding directions of the adjacent coil members are reversed, the driving current is increased by + U.
Phases, + U phase, + W phase, + W phase, + V phase, and + V phase may be supplied in this order.

Next, an extended example of the above embodiment will be described. FIG. 7 is an explanatory diagram of an extended example. Only differences from the above embodiment will be described. As shown in FIG. 7, the polarity is between adjacent permanent magnets (between 6-1 and 6-2, between 6-2 and 6-3, between 6-3 and 6-4,...). Are arranged in the X-axis direction. Further, the polarities of the auxiliary magnets 20 are alternately reversed in the arrangement order.

By adopting the above structure, the permanent magnets (between 6-1 and 6-2, between 6-2 and 6-3, 6-
It is possible to reinforce the magnetic flux density distribution between 3 and 6-4. If the magnetic flux density distribution when the auxiliary magnet 20 is not arranged is represented by the magnetic flux density distribution 20 without the auxiliary magnet in the figure, the magnetic flux density when the auxiliary magnet 20 is arranged is The magnetic flux density distribution 22 is as follows.

That is, in the magnetic flux density distribution 22 with the auxiliary magnet, both shoulder portions on the characteristic curve are reinforced compared to the magnetic flux density distribution 20 without the auxiliary magnet. As a result, the thrust of the linear motor increases.

In the above description, the X-direction linear motor 14 (FIG. 2) in the electronic component mounting apparatus (FIG. 2) of the present invention has been described. However, the Y-direction linear motor 12 (FIG. 2) is described in the same manner. Needless to say. or,
Although the description is omitted in the above description, the three-phase drive currents (U-phase, V-phase, and W-phase) of the linear motor are driven by a drive current supply device (not shown). By controlling the drive current supply device, the electronic component mounting device (FIG. 2) of the present invention is controlled.

[0057]

According to the present invention, the direction of the magnetic flux excited by the drive current coincides with the moving direction, and a plurality of hollow moving coils arranged side by side in the moving direction, and hollow moving coils of the upper side yoke and the lower side yoke. The electronic component mounting apparatus of the present invention, which is constituted by a linear motor having a plurality of permanent magnets arranged on the side surface in the moving direction and forming a field magnetic flux, has the following effects. 1. Since the use efficiency of the windings of the linear motor is improved, the volume for the electronic component mounting device is reduced in order to obtain a desired thrust. 2.
Since a non-magnetic reinforcing plate for reinforcing the hollow moving coil is not required, the magnetic resistance is reduced and the efficiency of the linear motor is improved, so that the volume of the electronic component mounting device for obtaining a desired thrust is reduced. 3. Since the direction of the magnetic flux generated by the drive current applied to the hollow moving coil does not match the direction of the field magnetic flux, the field magnetic flux is not disturbed. That is, the same phenomenon as the armature reaction in the rotating device is less likely to occur. As a result, the current-to-thrust linearity is improved, and the controllability of the electronic component mounting device is improved.
4. Since the leakage magnetic flux due to the hollow moving coil is reduced, the occurrence of eddy current in the U-shaped yoke is reduced.
As a result, a decrease in field magnetic flux can be prevented, so that a decrease in thrust of the electronic component mounting device can be prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a linear motor used in the present invention.

FIG. 2 is an explanatory view of an electronic component mounting apparatus of the present invention.

FIG. 3 is an explanatory diagram of a hollow moving coil.

FIG. 4 is an explanatory view of a magnetic pole arrangement.

FIG. 5 is an explanatory view (part 1) of the operation principle of the linear motor.

FIG. 6 is an explanatory view (part 2) of the operation principle of the linear motor.

FIG. 7 is an explanatory diagram of an extended example.

FIG. 8 is a configuration diagram of a conventional linear motor for an electronic component mounting apparatus.

FIG. 9 is a sectional view of a conventional linear motor for an electronic component mounting apparatus.

FIG. 10 is an explanatory diagram of a hollow moving coil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Linear motor 2 Hollow moving coil 3 Upper side yoke 4 Lower side yoke 5 Center yoke 6 Permanent magnet 7 Parts suction head 8 Yoke 9 Moving body mounting part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsu Muranishi 2-1-1 Oda Sakae, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture Inside Showa Electric Wire & Cable Co., Ltd. (72) Osamu Kokubo 2 Ei Oda, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture 1-1-1, Showa Electric Wire & Cable Co., Ltd. 2-1-1, Oda-ku, Ward Showa Electric Wire & Cable Co., Ltd. (72) Inventor Akihiko Nakamura 8-2-1 Kokuryo-cho, Chofu-shi, Tokyo Juku Corporation (72) Inventor Ichiro Okamoto Chofu, Tokyo (72) Inventor Naoyuki Yawata, 8-2 Kokuryo-cho, Kokuryo-cho, Tokyo Company in (72) inventor Hiroshi Anzai Chofu, Tokyo territory-cho, 8-chome address 2 1 di Yuki Co., Ltd. in the F-term (reference) 5E313 AA02 CC01 EE01 EE02 EE22 EE24 EE35

Claims (5)

[Claims] 1. A component suction head that sucks an electronic component and mounts it on a substrate; an X-direction movable body to which the component suction head is fixed; and an X that supports and drives the X-direction movable body so as to be movable in the X direction. Electronic device mounting apparatus comprising: a directional linear motor; a Y-direction moving body to which the X-directional linear motor is fixed; and a pair of Y-direction moving means for supporting and driving the Y-directional moving body movably in the Y direction. An X-direction linear motor, wherein: an upper side yoke and a lower side yoke each having a plurality of permanent magnets disposed inside; a center yoke interposed between the upper side yoke and the lower side yoke; The permanent magnet includes a hollow coil member that is movably wound around the center yoke and is arranged in a plural number in the longitudinal direction of the center yoke and that fixes the X-direction moving body. The stones are arranged such that the magnetic poles of the permanent magnets on the upper side yoke side and the permanent magnets on the lower side yoke side are opposite to each other, and the permanent magnets adjacent to each other along the longitudinal direction of the center yoke. Wherein the electronic component mounting apparatus is a linear motor in which the magnetic poles are arranged in opposite directions. 2. The device according to claim 1, wherein the Y-direction moving means is interposed between an upper side yoke and a lower side yoke each having a plurality of permanent magnets disposed inside, and the upper side yoke and the lower side yoke. A center yoke that is movably wound around the center yoke and arranged in a row in the longitudinal direction of the center yoke, and a hollow coil member to which the Y-direction moving body is fixed. The permanent magnets on the upper side yoke side and the permanent magnets on the lower side yoke side, each of which opposes the magnetic poles, are arranged in opposite directions, and the permanent magnets adjacent to each other along the longitudinal direction of the center yoke have magnetic poles. An electronic component mounting device, wherein the electronic component mounting device is a linear motor in which are arranged in opposite directions. 3. The electronic component mounting apparatus according to claim 1, wherein 4N (N is an integer) permanent magnets arranged along the moving direction of the coil member of the linear motor are used as a set. An electronic component mounting device, wherein when the position angle of the coil member is set to 4π, the length of the coil member in the moving direction is set to be equal to the position angle of 4π. . 4. The electronic component mounting apparatus according to claim 1, wherein the linear motor comprises a set of four permanent magnets and the permanent magnet set at the position angle of 4π, and a set of six linear motors comprising the same. And a coil member set to a length equal to the angle 4π. The set of six coil members includes a three-phase AC U-phase, a -U-phase, and a W phase,
An electronic component mounting apparatus to which -W phase, V phase, and -V phase are applied, respectively. 5. The electronic component mounting apparatus according to claim 1, wherein a magnetic pole is provided in the moving direction between all adjacent permanent magnets when viewed in the moving direction of the coil member of the linear motor. An electronic component mounting apparatus, wherein auxiliary magnets oriented in opposite directions are arranged.