WO2018003062A1

WO2018003062A1 - Linear motor, head unit, surface mounting machine, and single-axis robot

Info

Publication number: WO2018003062A1
Application number: PCT/JP2016/069447
Authority: WO
Inventors: 健士釣
Original assignee: ヤマハ発動機株式会社
Priority date: 2016-06-30
Filing date: 2016-06-30
Publication date: 2018-01-04
Also published as: CN109314456A; JP6616507B2; JPWO2018003062A1

Abstract

[Problem] To achieve a size reduction of a linear motor and enhance the speed of the servo control of the linear motor by improving the responsiveness of the linear motor. [Solution] A linear motor disclosed in this specification is a linear motor 40 having: an armature 45 in which a plurality of coil parts 46 are fixed to an attachment frame 41 in a form of being aligned in the vertical direction; and a field element 55 in which a plurality of permanent magnets 54 are aligned in the vertical direction so as to face the armature 45, wherein the field element 55 is longer than the armature 45 in the vertical direction, and the field element 55 is vertically movable relative to the armature 45. An optical linear scale 81 is directly fixed to the field element 55, and the attachment frame 41 is provided with a detection part 82 which optically detects the linear scale 81 and is disposed adjacent to the armature 45 in the vertical direction.

Description

Linear motor, head unit, surface mounter and single axis robot

The technology disclosed in this specification relates to a linear motor, a head unit, a surface mounter, and a single-axis robot.

For example, a linear motor that raises and lowers the suction nozzle in the vertical direction is known as disclosed in JP2013-143886A (Patent Document 1 below). This linear motor is provided on the frame so as to be aligned in the vertical direction with the coil provided on the frame, a slider having a permanent magnet disposed opposite to the coil and supported so as to be movable up and down on the frame. The slider is moved in the vertical direction by the attractive force generated between the coil and the permanent magnet by performing energization control on the coil.

The encoder includes a magnetic scale disposed below the permanent magnet in the slider and an encoder body supported by the frame so as to face the magnetic scale below the coil, and a detection sensor of the encoder body reads the magnetic scale. Thus, the vertical position of the slider is detected.

On the other hand, a detection unit that detects the vertical position of the slider has a sensor and a linear scale on the back side opposite to the front side, which is the coil side, with the slider as a boundary. This unit is fixed to the base plate. The detected sensor reads the linear scale affixed to the support provided on the movable base, thereby detecting the vertical position of the slider. As such a technique, one described in Japanese Patent No. 5250267 (Patent Document 2 below) is known.

JP 2013-143886 A Japanese Patent No. 5250267

By the way, in the above linear motor, the drive unit composed of the coil and the permanent magnet and the position detection unit for detecting the position information of the slider are arranged side by side in the vertical direction or the front-rear direction. Or it will enlarge in the front-back direction.

In addition, when the position of the drive unit and the position detection unit is separated, the slider moved by the drive unit is detected by the position detection unit separated from the drive unit, so the position detection unit follows the drive unit. And the responsiveness between the drive unit and the position detection unit is deteriorated. Therefore, the servo gain of the linear motor cannot be increased, and the servo control of the linear motor cannot be accelerated.

This specification discloses a technique for speeding up servo control of a linear motor by reducing the size of the linear motor and improving the response of the linear motor.

The technology disclosed in this specification is an armature in which a plurality of coil portions are linearly arranged, and a plurality of permanent magnets are arranged in the same direction as the arrangement direction of the coil portions so as to face the armature. And either one of the armature or the field element is longer in the arrangement direction than the other, and either the armature or the field element is relative to the other. The linear motor is movable in the arrangement direction, and the detected part is directly fixed to the longer one of the armature or the field element, and the shorter one of the armature or the field element The detection unit for optically detecting the detection target unit is provided adjacent to the detection unit.

The technology disclosed in this specification is a head unit having a component holding drive unit that moves a component holding unit that holds a component up and down, and the component holding drive unit includes the linear motor. It was set as the composition.
Further, the technology disclosed in this specification is configured such that the component holding drive unit includes a plurality of the linear motors together with the component holding unit.

The technology disclosed in the present specification is a surface mounter, which is a component mounter having the head unit, a component supply device that supplies the component to the component mounter, and the component mounter. And a board transfer device for transferring a board on which the component is mounted.

Further, the technology disclosed in this specification is a surface mounter including a head drive unit that moves a component mounting apparatus for mounting a component on a substrate in a horizontal direction, and the head drive unit includes the linear motor. It was set as the structure which has.
The technology disclosed in this specification is a single-axis robot including a pedestal drive unit that linearly moves the pedestal unit, and the pedestal drive unit includes the linear motor, and the electric machine It was set as the structure by which the child was provided in the said base part.

According to the linear motor having such a configuration, the detected part is directly fixed to the driving mechanism constituted by the armature and the field element, and the detecting part is provided adjacently. A mechanism and a position detection unit for detecting the position are individually provided, and the drive mechanism and the position detection unit are arranged in series in the movement direction of the linear motor, or the drive unit and the position detection unit are arranged in parallel. The linear motor can be reduced in size by the amount of overlap between the drive mechanism and the detected portion as compared with the case where the drive mechanism and the detected portion are overlapped.

Moreover, since it is not necessary to provide a drive mechanism and a position detection part separately, a linear motor can be reduced in weight.
In addition, since the detected part is directly fixed to a part of the driving mechanism, the driving mechanism and the position detecting part are arranged in series, or the driving part and the position detecting part are arranged in parallel. As compared with the above, the followability of the position detection unit with respect to the drive mechanism is enhanced, and the responsiveness between the drive mechanism and the position detection unit can be improved. Thereby, the servo gain of a linear motor can be raised and the servo control of a linear motor can be sped up.

The linear motor disclosed by this specification is good also as the following structures.
The surface of the armature and the field element to which the detected portion is fixed may be provided flat with resin, and the detected portion may be fixed to the resin.

According to such a configuration, the surface of the armature or the field element is covered with the resin, and the flatness of the portion to which the detected portion is fixed is high, so that the space between the detected portion and the detecting portion is high. The accuracy of the gap dimension can be increased. Thereby, it can prevent that a to-be-detected part becomes undetectable by a detection part.

The field element may be configured to be movable in the arrangement direction with respect to the armature.
According to such a configuration, since the detected portion is directly fixed to the field element movable with respect to the armature, the portion where the detected portion is fixed separately from the field element is the field element. The field element side can be reduced in weight compared with the case where it is provided on the side. Thereby, the field element side can be moved at higher speed.

The detection unit includes a sensor unit that detects the detected unit, and is arranged side by side in the movement direction so as to be adjacent to the armature, and the sensor unit of the detection unit includes the sensor unit in the detection unit. It is good also as a structure provided in the edge part by the side of an armature.

According to such a configuration, the sensor unit for detecting the detected portion is arranged adjacent to the armature side. For example, the sensor unit is provided at the end of the detection unit opposite to the armature. Compared with the case where it is made, the length of the to-be-detected part fixed to the field element can be shortened. Thereby, the length dimension of the arrangement direction of a field element can be shortened, and the field element side can be further reduced in weight.

The detected part is provided to extend from the field element in the moving direction, and the detected part extended from the field element is provided at a position adjacent to the field element in the arrangement direction. It is good also as a structure provided with the support part fixed.

In general, the field element that moves relative to the armature only needs to be provided up to the position where the armature is arranged. However, in order to detect the position of the field element by the armature-side detection unit, It is necessary to arrange the detected part up to the position of the detection part on the child side. That is, when the detected part is fixed to the field element, there is a disagreement that the field elements must be enlarged in the arrangement direction by the length from the armature to the position of the detecting part.

However, according to such a configuration, since the detected portion extending from the field element is fixed to the support portion provided adjacent to the field element, the field element increases in size in the moving direction. Can be prevented. Thereby, the quantity of the permanent magnet of a field element can be reduced.

According to the technology disclosed in this specification, the servo control of the linear motor can be speeded up by reducing the size of the linear motor and improving the response of the linear motor.

The top view of the surface mounting machine concerning Embodiment 1 Perspective view of head unit Front view AA line sectional view of FIG. Perspective view of linear motor Enlarged view of the main part of FIG. Side view of linear motor Side view showing a state where the mover has reached the final position in the linear motor Partially enlarged side view of the mover Side view showing relationship between armature and field element of linear motor Side view showing a mover according to Modification 1 Side view showing a mover according to Modification 2 The principal part enlarged view of the surface mounting machine which concerns on Embodiment 2. FIG. The perspective view of the linear guide apparatus which concerns on Embodiment 3. FIG. Partial cutaway plan view of linear guide device BB sectional view of FIG. Side view of another embodiment Plan view Side view of linear motor of conventional example 1 Side view of linear motor of conventional example 2

<Embodiment>
An embodiment of the technology disclosed in this specification will be described with reference to FIGS.
The present embodiment illustrates a surface mounter 10 that mounts an electronic component (an example of “component”) E on a printed circuit board (an example of “substrate”) P. In FIG. 1, some of the electronic components E accommodated in each feeder 16 described later are not shown.

As shown in FIG. 1, the surface mounter 10 includes a base 12 having a substantially rectangular shape in plan view, a transport conveyor (an example of a “board transport device”) 13 disposed on the base 12, and a printed circuit board P. And a component mounting apparatus 20 for mounting the electronic component E. In the following description, the long side direction of the base 12 and the transport direction of the transport conveyor 13 in FIG. 1 will be described as the left-right direction, and the short side direction of the base 12 will be described as the front-back direction. The vertical direction will be described with reference to the vertical direction of the component mounting apparatus 20 in FIG.

As shown in FIG. 1, the base 12 is a base on which a transport conveyor 13, a component mounting apparatus 20, and the like are arranged. An electronic component is placed on the printed circuit board P below the transport conveyor 13 in the base 12. When E is mounted, a backup plate (not shown) for backing up the printed circuit board P is provided.

As shown in FIG. 1, the transport conveyor 13 is arranged at a substantially central portion in the front-rear direction of the base 12 and transports the printed board P in the left-right direction. Further, the transport conveyor 13 includes a pair of conveyor belts 15 that circulate and drive in the left-right direction, and a printed circuit board P is set on the pair of conveyor belts 15 so as to be installed. Then, the printed circuit board P is loaded from the right side along the conveyor belt 15 into the mounting range in the substantially central portion on the base 12 in the left-right direction, and after the electronic component E is mounted, the printed board P is left along the conveyor belt 15. It is carried out to.

As shown in FIG. 1, the component supply device 14 is a feeder type, and two parts are arranged in the left and right directions on both sides in the up and down direction of the transport conveyor 13, and are arranged in a total of four locations. A plurality of feeders 16 are attached to these component supply devices 14 so as to be aligned in the left-right direction. Each feeder 16 includes an unillustrated electric delivery device that pulls out a component supply tape containing a plurality of electronic components E from a reel, and the electronic components E are fed from the end of each feeder 16 on the side of the conveyer 13. One by one is supplied.

As shown in FIG. 1, the component mounting apparatus 20 includes a pair of support frames 21 arranged on both sides in the left-right direction of the base 12, a head unit 30, and a head driving device 22 that moves the head unit 30. Configured. Each support frame 21 has an elongated shape extending in the front-rear direction, and is disposed on each side of the base 12 in the left-right direction.

The head drive device 22 includes a Y-axis servo mechanism 23 and an X-axis servo mechanism 27 and is provided so as to be installed on the pair of support frames 21.
As shown in FIG. 1, the Y-axis servo mechanism 23 includes a pair of Y-axis guide rails 24 provided along each support frame 21 in a form extending in the left-right direction and a Y-axis in which a ball nut (not shown) is screwed. It has a shaft ball screw 25A and a Y-axis servomotor 25 provided at the end of the Y-axis ball screw 25A. A pair of Y-axis guide rails 24 have a head support 26 fixed to a ball nut. Is installed in the form of erection.

When the Y-axis servomotor 25 is energized, the ball nut advances and retreats along the Y-axis ball screw 25A. As a result, the head support 26 fixed to the ball nut and the head support 26 are mounted. The head unit 30 moves in the front-rear direction along the Y-axis guide rail 24.

As shown in FIG. 1, the X-axis servo mechanism 27 includes an X-axis guide rail (not shown) provided on the head support 26 in a form extending in the left-right direction and a ball nut (not shown) screwed together. A ball screw 28A and an X-axis servomotor 28 provided at the end of the X-axis ball screw 28A are provided. A head unit 30 is attached to the X-axis guide rail so as to be movable in the left-right direction. When the X-axis servo motor 28 is energized and controlled, the ball nut advances and retreats along the X-axis ball screw 28A. As a result, the head unit 30 fixed to the ball nut moves in the left-right direction along the X-axis guide rail.
As a result, the head unit 30 is movable on the base 12 in the horizontal direction, which is the front / rear / right / left direction.

As shown in FIGS. 2 to 4, the head unit 30 has a shape that is long in the vertical direction, and includes a metal unit frame 31, a component holding unit 60 that holds the electronic component E, and a plurality of component holding units 60. A component holding drive unit 32 that is driven up and down and an R-axis servo mechanism 70 that rotates the component holding unit 60 are provided.

As shown in FIG. 3, a plurality of (10 in the present embodiment) side-by-side components are provided in the lower end of the component holding drive unit 32 as shown in FIG. And a nozzle 62 attached to the lower end of the drive shaft 61. The nozzle 62 is connected to a valve switch 65 provided on the top of the head unit 30 via a drive shaft 61, a resin pipe 63, and the like. A negative pressure suction force is applied from a negative pressure generator (not shown), and the electronic component E is sucked and held at the lower end of the nozzle 62.

Further, a cylindrical shaft holder 66 is mounted on the outer periphery of the drive shaft 61. The shaft holder 66 is interlocked with the R-axis servo mechanism 70 via the belt 71, and the component holding portion 60 is rotated around the axis when the R-axis servo mechanism 70 is operated.

The component holding drive unit 32 includes a plurality of linear motors 40 and a fixed frame 33 that fixes the plurality of linear motors 40.
As shown in FIG. 3, the fixed frame 33 is substantially U-shaped when viewed from the front, and fixes a plurality of linear motors 40 side by side between the side walls 33A at both left and right ends.

Each linear motor 40 is provided so as to correspond to the component holding unit 60, and the nozzle 62 is moved in the vertical direction with respect to the component supply device 14 and the printed circuit board P by driving the component holding unit 60 up and down. This is a drive mechanism. Each linear motor 40 includes a metal mounting frame 41 and a mover 50 that is held so as to be linearly movable in the vertical direction with respect to the mounting frame 41, as shown in FIGS. Configured. In the description of the linear motor 40, FIGS. 5 to 11 show the front side and the rear side reversed, and in FIG. 9, the Z rail 52 of the mover 50 described later is omitted. .

The mounting frame 41 is configured such that a frame portion 43 having a rectangular shape in side view is integrally provided on a peripheral portion of a flat plate 42 having a substantially rectangular shape in side view that is long in the vertical direction. The linear motor 40 is held by the unit frame 31 by screwing the provided upper and lower slide bases 44 to the unit frame 31 with screws.

The armature 45 having a plurality of coil portions 46 is fixed to the front lower portion of the frame portion 43 of the mounting frame 41 by screws. The armature 45 is also a stator fixed to the mounting frame 41.

The armature 45 has a comb-shaped core 47 made of a plurality of electromagnetic steel plates, and a coil is wound around each comb-shaped tooth portion 47 </ b> A provided on the core 47, so that the vertical direction A plurality of coil portions 46 arranged in a row are configured.

The mover 50 is longer than the armature 45 in the mounting frame 41 in the vertical direction by a factor of two or more. The mover 50 is provided with a clearance of a predetermined size in the front-rear direction between the armature 45 and the armature 45 in the mounting frame 41, and is provided opposite to the front-rear direction behind the armature 45. Yes.

Further, as shown in FIG. 7, the mover 50 is configured such that the Z rail 52 is slidably fitted to the pair of slide bases 44 in the mounting frame 41 so that the upper end portion of the mover 50 is As shown in FIG. 8, the lower half of the mover 50 extends from the mounting frame 41 as shown in FIG. It is possible to move up and down between the final position protruding downward. In other words, the mover 50 is movable in the vertical direction with respect to the armature 45 that is a stator.

The mover 50 includes a mover main body 51 extending in the vertical direction and a Z rail 52 fixed to the rear surface of the mover main body 51. The lower end of the mover main body 51 is a component holding unit 60. The upper end of each is a fixed portion 53 fixed with screws.

A plurality of permanent magnets 54 are fixed over the entire length of the front surface of the movable body 51 from the fixed portion 53 so as to be arranged at equal pitches in the vertical direction, and a field element 55 is provided. Yes. The permanent magnet 54 in the field element 55 has a front surface facing the armature 45 as a magnetic pole, and the permanent magnet 54 is arranged so that N poles and S poles alternate in the vertical direction. ing.

Here, the installation range of the permanent magnet 54 with respect to the movement range of the needle | mover 50 is demonstrated with reference to FIG.
The installation range of the permanent magnet 54 necessary for moving the mover 50 in the vertical direction is arranged so that at least the entire coil portion 46 of the armature 45 and the permanent magnet 54 always face each other in the front-rear direction.

Specifically, as shown in FIG. 10, the permanent magnet 54 of the mover 50 includes a coil unit 46 and a field element 55 arranged at the upper end of the armature 45 when the mover 50 is arranged at the final position. It arrange | positions so that the permanent magnet 54 distribute | arranged to the upper end part of may correspond. Further, when the mover is arranged at the initial position, the coil part 46 arranged at the lower end part of the armature 45 and the permanent magnet 54 arranged at the lower end part of the field element 55 are arranged to coincide with each other.
That is, the minimum installation range L3 of the permanent magnet 54 in the mover 50 includes at least the movement distance (movement distance from the initial position to the final position) L1 of the mover 50 and the overall length L2 of the coil portion 46. This is the length dimension.

The field elements 55 in the mover 50 are arranged so that the permanent magnets 54 face each other over the entire coil portion 46 in the armature 45 because the permanent magnets 54 having substantially the same shape are arranged at equal pitches in the vertical direction. To this end, the permanent magnet 54 at the upper end portion of the field element 55 may protrude above the coil portion 46 at the upper end portion of the armature 45 at the final position. On the contrary, the permanent magnet 54 at the lower end may protrude below the coil portion 46 at the lower end of the armature 45 at the initial position. Therefore, the minimum installation range L3 of the permanent magnet 54 may be larger than the sum of the moving distance L1 of the mover 50 and the overall length L2 of the coil portion 46.

In addition, in order to install a linear scale, which will be described later, the permanent magnet 54 in this embodiment has a sensor offset range L4, which will be described later, in addition to the minimum installation range L3 of the permanent magnet 54, as shown in FIG. The configuration is included.

Therefore, in the present embodiment, as shown in FIG. 7, in a state where the mover main body 51 is arranged at the initial position, the field element 55 is arranged slightly below the armature 45, as shown in FIG. In addition, in a state where the mover main body 51 is disposed at the final position, the field element 55 is disposed slightly above the armature 45. Note that the thickness dimension of the permanent magnet 54 in the present embodiment is substantially uniform, and the front surface of the field element 55 is flat so as not to be uneven.

When energization control is performed on the coil portion 46 in the armature 45 of the mounting frame 41, an attractive force is generated between the armature 45 and the field element 55 of the mover 50, so that the mounting frame 41. In contrast, the movable element 50 can be moved in the vertical direction.

That is, the linear motor 40 is a moving magnet type linear motor, and the head unit 30 is fixed to the fixed portion 53 of the movable element main body 51 in accordance with the vertical movement of the movable element 50 in the linear motor 40. The component holding unit 60 is moved up and down, and the nozzle 62 of the component holding unit 60 can be moved up and down with respect to the component supply device 14 and the circuit board.

Note that, in addition to the component holding portion 60, a return spring 90 that urges the mover 50 upward is attached to the fixed portion 53 of the mover main body 51. The return spring 90 prevents the component holding portion 60 from descending when the coil portion 46 of the armature 45 is in a non-energized state and no attractive force acts between the armature 45 and the field element 55. It is like that.

A linear encoder 80 that detects the position of the mover 50 is provided between the field element 55 and the mounting frame 41 of the mover 50 of the linear motor 40.

Specifically, an optical linear scale (an example of “detected portion”) 81 extending in the Z direction is provided on the front surface of the field element 55 in the mover 50 of the linear motor 40, and Above the armature 45, a detection unit 82 that optically detects the linear scale 81 in a form facing the linear scale 81 in the front-rear direction is screwed to the mounting frame 41.

The detection unit 82 has an elongated shape in the vertical direction, and is fixed at a position adjacent to the armature 45 immediately above the armature 45. The detection unit 82 includes a main body portion 84 having a substantially rectangular plate-like substrate portion 83 that is long in the vertical direction, and a sensor portion 85 fixed to the rear surface 83A of the substrate portion 83.

The main body 84 has a detection unit 82 screwed to the mounting frame 41 by inserting fixing screws 86 into both upper and lower ends of the main body 84 and tightening the flat plate 42 of the mounting frame 41. In the armature 45 side. Therefore, as shown in FIG. 10, the sensor unit 85 is arranged so as to be offset upward from the coil unit 46 at the upper end of the armature 45 by the sensor offset range L4 (about two permanent magnets). Yes.

On the other hand, the linear scale 81 is formed in a thin band shape from a non-magnetic stainless steel, and has optical scales in the vertical direction at intervals of several tens of micro pitches, for example. Therefore, the position of the field element 55 and the mover 50 can be detected by optically reading the scale of the linear scale 81 by the sensor unit 85 of the detection unit 82.

The linear scale 81 is fixed to the front surface of the permanent magnet 54 in the field element 55 by a known method such as a double-sided tape or an adhesive, and the measurement range is at least the position of the mover 50. Is set to a range where it can be detected.

In other words, the measurement range of the linear scale 81 in the present embodiment is at least the same length as the moving distance of the mover 50. Specifically, as shown in FIG. A range between the position P1 facing the front and rear of the sensor unit 85 and the length of the movable element 50 extended by the moving distance L1 when it is arranged at the position is a measurement range L5.

Then, as shown in FIGS. 7, 8, and 10, the linear scale 81 is installed in a slightly larger range L6 before and after the measurement range L5, so that the sensor unit 85 of the detection unit 82 and the linear scale 81 Is always opposed in the front-rear direction between the initial position and the final position, so that the position of the mover 50 between the initial position and the final position can be detected.

According to the present embodiment, the sensor unit 85 in the detection unit 82 is disposed above the coil unit 46 at the upper end of the mover 50 by the length of the sensor offset range L4. Therefore, the permanent magnets 54 in the field element 55 of the mover 50 are installed more than the minimum installation range L3 by the sensor offset range L4 (two permanent magnets).

The present embodiment is configured as described above, and subsequently, the operation and effect of the surface mounter 10 will be described.
According to the linear motor 40 of the head unit 30 of the present embodiment, as shown in FIGS. 5 to 8, the field element 55 of the mover 50 of the linear motor 40 which is a drive mechanism for moving the component holding portion 60 in the vertical direction. Since the linear scale 81 is directly fixed to the movable element 50, a portion for fixing the linear scale 81 does not need to be provided separately from the field element 55 in the movable element 50. Can be lighter.

Further, according to the present embodiment, since the detection unit 82 of the linear encoder 80 is arranged in the dead space immediately above the armature 45 generated between the frame portion 43 and the mover 50 in the mounting frame 41, the linear motor 40 can be prevented from becoming large.

That is, for example, as shown in FIG. 19, the armature 2 having the coil portion 2 </ b> A and the detection portion 3 </ b> A of the position detection encoder 3 are moving directions of the mover 4 having the field element 4 </ b> A made of a permanent magnet. As shown in FIG. 20, the linear motor 1 arranged in series in the vertical direction and the armature 7 and the position detecting encoder 8 are arranged in parallel in the front-rear direction (with the movable element 6 interposed therebetween). Compared with the linear motor 5 in which the position detecting encoder 8 is arranged on the rear side opposite to the armature 7, the field element 55 of the movable element 50 and the linear scale 81 are overlapped. The linear motor 40 can be reduced in size. As a result, the head unit 30 having a plurality of linear motors 40 can be reduced in size and weight.

Moreover, according to this embodiment, since the sensor part 85 of the detection part 82 fixed to the attachment frame 41 is disposed at the lower end part on the armature 45 side, for example, the sensor part is provided at the upper end part of the detection part. Compared with the case where it is, the length dimension of the linear scale 81 fixed to the field element 55 of the needle | mover 50 can be shortened. Thereby, the vertical dimension of the field element 55 and by extension, the needle | mover 50 can be shortened, and the needle | mover 50 can be further reduced in weight.

Further, according to the present embodiment, the linear scale 81 is directly fixed to the field element 55 of the mover 50, so that the drive mechanism constituted by the field element 55 and the armature 45, the linear scale 81, and the detection unit 82. The distance between the linear encoder 80 and the linear encoder 80 is made very small to increase the rigidity between the driving mechanism and the linear encoder 80, so that the followability of the linear encoder 80 to the driving mechanism is increased. Therefore, the responsiveness between the drive mechanism and the linear encoder 80 can be improved.

That is, according to this embodiment, the linear motor 40 can be reduced in weight, so that the mover 50 can be speeded up, and the followability of the linear encoder 80 can be improved to improve the responsiveness of the linear motor 40. Therefore, the servo gain of the linear motor 40 can be increased and the servo control of the linear motor 40 can be speeded up.

By the way, as a method of reducing the distance between the drive mechanism and the encoder, the position information of the mover is acquired by detecting the N pole and the S pole in the permanent magnet of the field element by a magnetic sensor. A method is conceivable.

However, according to such a method, in order to improve the accuracy of the position information of the mover, it is necessary to reduce the size of the permanent magnet in the field element and reduce the pitch between the N pole and the S pole. For this reason, there is a limit to reducing the size of the permanent magnet while maintaining the thrust of the linear motor, and the accuracy of the position information of the mover cannot be improved.

However, according to the present embodiment, since the optical linear scale 81 having a very fine scale pitch is pasted and fixed on the field element 55, the position information of the mover 50 is not affected by the magnetic field. The accuracy can be improved and the linear scale 81 can be attached to the field element 55 very easily.

<Modification 1>
Next, Modification 1 of the mover 50 in Embodiment 1 will be described with reference to FIG. In FIG. 11, the Z rail is not shown.
The mover 150 of the first modification is obtained by changing the field element 55 of the mover 50 in the first embodiment, and the configuration, operation, and effect common to the above-described embodiment are duplicated. Omitted. Moreover, the same code | symbol shall be used about the same structure as the said embodiment.

As shown in FIG. 11, the field element 155 of the mover 150 according to the first modification is resin-molded with a plurality of permanent magnets 154 arranged in the vertical direction, and the front surface 155A of the resin-molded field element 155 is: It is formed flat.
A linear scale (an example of a “detected portion”) 81 is fixed to a flat front surface 155A of the field element 155 by a known method such as a double-sided tape.

That is, according to such a configuration, even when the thickness dimension of the permanent magnet 154 is not uniform, the front surface 155A of the field element 155 is configured in a flat state without unevenness, and the front surface 155A of the field element 155 is The flatness can be increased, and variations in the gap dimension between the linear scale 81 and the sensor unit 85 in the detection unit 82 can be prevented. Thereby, it can prevent that the linear scale 81 becomes undetectable by the detection part 82. FIG.

<Modification 2>
Next, Modification 2 of the mover 50 in Embodiment 1 will be described with reference to FIG.
The mover 250 in the linear motor 240 according to the second modification is obtained by changing the configuration of the mover 50 in the first embodiment, and the configuration, operation, and effect common to the above-described embodiment are duplicated. Is omitted. Moreover, the same code | symbol shall be used about the same structure as the said embodiment.

As shown in FIG. 12, the mover 250 according to the second modification includes a mounting base portion 256 (an example of a “support portion”) 256 having a thickness substantially the same as that of the permanent magnet 54 above the field element 255 in the mover 250. It is provided adjacent to the magnetic element 255. The vertical dimension of the mounting table 256 is slightly longer than the length (the sensor offset range L4) between the upper coil part 46 of the armature 45 and the sensor part 85 of the detection part 82. Is provided.

A linear scale (an example of a “detected portion”) 281 extending upward from the upper end position of the field element 255 is fixed to the front surface of the mounting table portion 256 over the entire length of the mounting table portion 256. Yes.

Therefore, according to this modification, the length dimension of the field element 255 in the vertical direction is shorter than the length dimension of the field element 55 of the first embodiment by the length dimension in the vertical direction of the mounting table 256. In the state where the mover 250 is arranged at the final position, the sensor unit 85 of the detection unit 82 can detect the position of the mover 250 by reading the linear scale 281 fixed to the mounting table unit 256. It can be done.

In other words, the field element for driving the mover only needs to be provided up to the position where the armature is arranged. However, in order to detect the position of the mover by the detection unit, the position of the sensor unit of the detection unit is required. It is necessary to arrange a linear scale. For this reason, when the linear scale is fixed to the field element, there is a disagreement that the field element has to be enlarged in the vertical direction by the length dimension from the armature to the position of the detection unit.

However, according to the present embodiment, since the linear scale 281 extending upward from the field element 255 is fixed to the mounting table portion 256 provided adjacent to the upper side of the field element 255, the field element The length dimension in the vertical direction of 255 can be reduced. Thereby, the quantity of the permanent magnet 54 of the field element 255 can be reduced.

<Embodiment 2>
Next, Embodiment 2 will be described with reference to FIG.
The surface mounter 310 according to the second embodiment is obtained by changing the driving method for moving the head unit 30 in the left-right direction in the component mounting apparatus 20 according to the first embodiment. Since the effect is duplicated, its description is omitted. The same reference numerals are used for the same configurations as those in the first embodiment.

As shown in FIG. 13, the component mounting apparatus 320 in the surface mounter 310 according to the second embodiment has an X frame 321 fixed to a base (not shown) in a form extending in the left-right direction, and forward from the X frame 321. A cantilever Y arm 322 that extends, a head unit 330 supported by the Y arm 322, and a head drive unit 340 that moves the head unit 330 back and forth and from side to side.

The X frame 321 is provided with a pair of upper and lower linear guides 324 extending in the left-right direction over the entire length of the X frame 321, and the Y arm 322 extends along the linear guide 324 while being fitted to the linear guide 324. A movable first slider 325 is provided. Therefore, the Y arm 322 is held so as to be linearly movable in the left-right direction along the X frame 321.

The Y arm 322 is provided with a pair of upper and lower guide rails 323 extending in the front-rear direction over the entire length of the Y arm 322, and the head unit 330 is moved back and forth along the guide rail 323 while being fitted to the guide rail 323. An X-direction slider (not shown) that can move in the direction is provided. Thereby, the head unit 330 is movable in the front-rear direction along the Y arm 322.
Therefore, the head unit 330 is movable in the horizontal direction, which is the front / rear / left / right direction, on the base.

On the other hand, the head drive unit 340 includes a first servo mechanism 341 and a second servo mechanism 346.
The first servo mechanism 341 is provided at the end of the Y arm 322 on the X frame 321 side, and a field element 342 which is provided on the inner surface of the X frame 321 and is formed of a permanent magnet (not shown) and which is long in the left-right direction. The field element 342 is longer in the left-right direction than the armature 343.
Then, by performing energization control on the coil of the armature 343, the Y arm 322 is moved in the left-right direction by the attractive force generated between the coil of the armature 343 and the permanent magnet of the field element 342. ing. That is, the first servo mechanism 341 of the present embodiment is a moving coil type linear motor.

The second servo mechanism 346 includes a ball screw shaft 335 provided in the head unit 330 in a form extending in the front-rear direction, and a servo motor 333 that drives the ball screw shaft 335. This servo motor The head unit 330 can be moved in the front-rear direction by rotating a ball screw (not shown) attached to the Y arm 322.

That is, the head unit 330 can be moved to desired positions in the front-rear direction and the left-right direction by the first servo mechanism 341 and the second servo mechanism 346.

In the present embodiment, an optical linear scale (an example of a “detected portion”) 381 extending in the left-right direction is fixed to a substantially central portion in the up-down direction of the field element 342, and on the side surface of the armature 343. A detection unit 382 for optically detecting the linear scale 381 is fixed at a substantially central portion in the vertical direction. The linear scale 381 with respect to the field element 342 and the detection unit 382 with respect to the armature 343 are fixed by a known method such as a double-sided tape.

That is, according to the present embodiment, the linear scale 381 is fixed on the surface of the field element 342 and the detection unit 382 is fixed on the side surface of the armature 343, so that the linear scale 381 is supported with respect to the X frame 321. There is no need to provide a separate portion, and the X frame 321 can be prevented from becoming large or complicated.

Further, since the linear scale 381 is directly fixed to the surface of the field element 342 and the detection unit 382 is directly fixed to the side surface of the armature 343, the first servo mechanism configured by the field element 342 and the armature 343 is provided. 341 and the rigidity between the linear encoder 380 configured by the linear scale 381 and the detection unit 382 are increased, and the followability of the linear encoder 380 with respect to the first servo mechanism 341 can be increased. Thereby, the responsiveness of the first servo mechanism 341 can be improved.

That is, according to the present embodiment, the response of the first servo mechanism 341 is improved by improving the followability of the linear encoder 80. Therefore, the servo gain of the first servo mechanism 341 is increased and the first servo mechanism 341 is increased. Servo control can be speeded up.

<Embodiment 3>
Next, Embodiment 3 will be described with reference to FIGS.
This embodiment is a linear guide device (an example of a “single-axis robot”) 410 that moves the pedestal portion 430 in the front-rear direction, and includes a base 412 and a pair of support frames 420 provided on the base 412. A pedestal portion 430 that is movably held by the pair of support frames 420 and a pedestal drive portion 440 that drives the pedestal portion 430 are configured. In the following description, the front-rear direction will be described with the left side in the figure as the front side and the right side in the figure as the rear side with reference to the left-right direction in FIG.

As shown in FIGS. 14 and 15, the base 412 has a substantially rectangular shape in plan view extending in the front-rear direction, and a pair of support frames 420 are disposed on both sides in the width direction of the base 412.
The pair of support frames 420 extend in the front-rear direction at both ends in the width direction of the base 412, and extend in the front-rear direction over the entire length of the support frame 420 at the upper end of each support frame 420. A guide rail 421 is provided.

The pedestal portion 430 has a substantially rectangular flat plate shape in plan view, and a pair of front and rear sliders 431 are provided on the bottom surfaces of both sides of the pedestal portion 430 in the width direction. The slider 431 is movable in the front-rear direction along the guide rail 421 while being fitted to the guide rail 421 of the support frame 420, and the pedestal portion 430 can be moved back and forth by moving the slider 431 back and forth. It is said that.

The pedestal drive unit 440 includes an armature 441 composed of a plurality of coil portions (not shown) and a field element 442 composed of a plurality of permanent magnets 454.
The armature 441 has a flat block shape and is fixed to a substantially central portion in the width direction on the lower surface of the pedestal portion 430. Electric power is supplied to a coil portion of the armature 441 from a cable (not shown) inserted through a cable guide portion 413 provided on a side portion of the base 412.

The field element 442 is configured by fixing a plate-like permanent magnet 454 between the pair of support frames 420 to the base 412 so that the N pole and the S pole are alternately arranged in the front-rear direction. The entire length of the base 412 is provided. In other words, the field element 442 is longer than the armature 441.

Then, energization control is performed on the coil portion of the armature 441, whereby an attractive force is generated between the coil portion of the armature 441 and the permanent magnet 454 of the field element 442, and the base 412 is pedestal. The part 430 moves in the front-rear direction. That is, the pedestal drive unit 440 in the present embodiment is also a moving coil type linear motor, as in the second embodiment.

In this embodiment, an optical linear scale (an example of a “detected portion”) 481 extending in the front-rear direction is fixed to a substantially central portion in the width direction of the field element 442, and is arranged on the front surface of the armature 441. A detection unit 482 that optically detects the linear scale 481 is fixed at a substantially central portion in the width direction. The linear scale 481 with respect to the field element 442 and the detection unit 482 with respect to the armature 441 are fixed by the same method as in the first and second embodiments.

That is, according to the present embodiment, the linear scale 481 is fixed to the upper surface of the field element 442, and the detection unit 482 is fixed to the front surface of the armature 441. Therefore, the portion that supports the linear scale with respect to the support frame 420 The support frame 420 can be prevented from becoming large or complicated. In addition, since it is not necessary to provide a detection unit for detecting a linear scale separately provided on the side of the support frame, the linear guide device 410 can be prevented from being enlarged.

Furthermore, according to the present embodiment, the linear scale 481 is directly fixed to the upper surface of the field element 442, and the detection unit 482 is directly fixed to the front surface of the armature 441. Therefore, the field element 442 and the armature 441 are configured. The rigidity between the pedestal drive unit 440 and the linear encoder 480 configured by the linear scale 481 and the detection unit 482 is increased, and the followability of the linear encoder 480 with respect to the pedestal drive unit 440 can be enhanced. That is, the responsiveness between the pedestal drive unit 440 and the linear encoder 480 can be improved, the servo gain of the pedestal drive unit 440 can be increased, and the servo control of the pedestal drive unit 440 can be speeded up.

<Other embodiments>
The technology disclosed in the present specification is not limited to the embodiments described with reference to the above description and drawings, and includes, for example, the following various aspects.
(1) In the above embodiment, the

linear scales

81, 281, 381, 481 are made of nonmagnetic stainless steel. However, the present invention is not limited to this, and the linear scale may be made of a nonmagnetic metal or glass. If the magnetic field lines of the permanent magnet of the field element are not completely shielded and are made thin enough to pass the armature and the mover can be driven sufficiently, the linear scale can be made of a magnetic metal (magnetic stainless steel). May be included).

(2) In the above embodiment, the

linear scales

81, 281, 381, and 481 are fixed to the

field elements

55, 155, 255, 342, and 442 by double-sided tape or the like. However, the present invention is not limited to this, and the lower end portion of the linear scale may be embedded in the resin portion of a field element formed by resin molding of a permanent magnet.

(3) In the above embodiment, the

armature

45, 343, 441 is configured to have a long field element. However, the present invention is not limited to this, and as shown in FIGS. 17 and 18, an armature 545 formed by resin molding a plurality of coil portions 546 is formed longer than a field element 555 formed by arranging a plurality of permanent magnets 554. The linear motor 540 may be configured, and the linear scale 581 attached to the surface of the armature 545 longer than the field element 555 is detected by the detection unit 582 provided adjacent to the field element 555. It is good also as a structure.

(4) In the third embodiment, the detection unit 482 is fixed to the front surface of the armature 441 including the coil unit. However, the configuration is not limited to this, and the detection unit may be embedded in the armature together with the coil unit.
(5) In the first embodiment, the detection unit 82 is disposed above the armature 45. However, the configuration is not limited to this, and the detection unit may be arranged below the armature. Even when the detection unit is arranged below the armature, the minimum permanent magnet installation range and the linear scale installation range in the field element of the mover should be determined by the same method as in the first embodiment. Can do.

10, 310: Surface mounter 13: Conveyor (an example of “substrate transport device”)
20, 320: Component mounting device 22: Head drive unit 30: Head unit 32: Component holding drive unit 40: Linear motor 41: Mounting frame 45: Armature 46:

Coil units

55, 155, 255, 342, 442: Field Child 60:

component holding parts

81, 281, 381, 481: linear scale (an example of “detected part”)
82, 382, 481: detection unit 85: sensor unit 256: mounting table unit (an example of “support unit”)
342, 442: Field element 343, 441: Armature 410: Linear guide device (an example of “single axis robot”)
440: Pedestal drive unit E: Electronic component (an example of “component”)
P: Printed circuit board (an example of “board”)

Claims

An armature in a form in which a plurality of coil portions are linearly arranged;
A field element in which a plurality of permanent magnets are arranged in the same direction as the arrangement direction of the coil portions so as to face the armature,
Either the armature or the field element is longer in the alignment direction than the other, and either the armature or the field element is movable in the alignment direction with respect to the other Because
The detected part is directly fixed to the longer one of the armature or the field element, and the detecting part for optically detecting the detected part is adjacent to the shorter one of the armature or the field element. A linear motor is provided.
The surface of the armature or the field element to which the detected portion is fixed is provided flat by resin,
The linear motor according to claim 1, wherein the detected portion is fixed to the resin.
The linear motor according to claim 1, wherein the field element is movable in the movement direction with respect to the armature.
The detection unit includes a sensor unit that detects the detected unit, and is provided side by side in the movement direction so as to be adjacent to the armature.
The linear motor according to claim 3, wherein the sensor unit of the detection unit is provided at an end of the detection unit on the armature side.
The detected portion is provided to extend from the field element in the moving direction,
The linear motor according to claim 4, wherein a support part to which the detected part extending from the field element is fixed is provided at a position adjacent to the field element in the moving direction.
A head unit having a component holding drive unit that moves a component holding unit that holds components up and down,
The said component holding drive part is a head unit which has the linear motor as described in any one of Claims 1-5.
The head unit according to claim 6, wherein the component holding drive unit includes a plurality of the linear motors together with the component holding unit.
A component mounting apparatus having the head unit according to claim 6 or 7,
A component supply device for supplying the component to the component mounting device;
A surface mounting machine comprising: a substrate transfer device that transfers a substrate on which the component held by the component mounting device is mounted.
A surface mounter including a head drive unit that horizontally moves a component mounting apparatus for mounting a component on a board,
3. The surface mounter, wherein the head driving unit has the linear motor according to claim 1 or 2.
A single-axis robot provided with a pedestal drive that linearly moves the pedestal,
The pedestal drive unit has the linear motor according to claim 1 or claim 2,
A single-axis robot in which the armature is provided on the pedestal.