JP2009148893A - Moving body system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress deterioration of positioning accuracy due to a weight of a rail raceway and a moving body, without causing enlargement and increase of the weight. <P>SOLUTION: In a sectionally U-shaped rail raceway 30, distortion is generated due to its own weight. By holding a component adsorption head 132 with a moving body 31 on a shearing center S of this distortion, the distortion of the rail raceway 30 is suppressed and positional deviation of the moving body 31 in a height direction is suppressed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a moving body system that moves a moving body along a track.

  2. Description of the Related Art Conventionally, in semiconductor factories and the like, a system for moving a moving body equipped with a device such as a work robot along a rail track is used. As such a mobile system, a linear motor system, a ball screw system, or the like is used.

  Here, FIG. 1 shows a configuration of a mobile system using a conventional linear motor system. As shown in the figure, in this system, the moving body 3 is guided and supported by a linear guide portion 2 along a track 1 having a U-shaped cross section laid in the direction perpendicular to the drawing sheet. The moving body 3 includes a magnetic field generating mechanism 8 that includes a core 4, a coil 5 that is wound around the core 4, and a support member 9 that supports the core 4. In this magnetic field generating mechanism 8, by supplying a current to the coil 5, a magnetic field is generated between the secondary side core 6 disposed at a position facing the core 4 in the track 1, thereby generating a thrust. To move the moving body 3.

  Such a moving body 3 is provided with a mounting portion 7 on which a component suction head for sucking semiconductor components and the like are mounted in addition to the magnetic field generating mechanism 8 that generates the thrust described above. Here, the mounting portion 7 and the support member 9 of the magnetic field generation mechanism 8 are fixed by bolts 10. Therefore, if a mounting head or the like is mounted on the mounting portion 7, the component suction head can be moved to an arbitrary position in the track 1.

  By the way, in the mobile body system, in order to arbitrarily move the robot mounted on the mobile body 3 described above not only on a certain straight line but also in a plane (X direction, Y direction) within a predetermined range, FIG. A system as shown may be used. As shown in the figure, in this system, the linear motor system 16 (see FIG. 1) including the track 1 and the moving body 3 laid in the X-axis direction can be moved in the Y-axis direction by a ball screw method. I am doing so. Specifically, the linear motor system 16 is fixed to a frame driven by a ball screw 15 and the ball screw 15 is driven by a motor 17 so that the entire linear motor system 16 can be moved in the Y-axis direction. It has become. According to this system, the movable body 3 can be moved to an arbitrary position on the XY plane by controlling the driving of both the ball screw 15 and the linear motor.

Japanese Utility Model Publication No.59-13001

  However, in a moving body system used in a semiconductor factory or the like, the moving body 3 is equipped with work equipment such as a component suction head, and the movement of the moving body 3 in the X-axis direction causes the track 1 in the figure to have a clock. A moment acts in the rotating direction, that is, twisting occurs.

  When the member having a U-shaped cross section as described above is twisted, its shear center S is in the position shown in the figure, and in the case of the mobile body system configured as described above, the shear center S is opposite to the mobile body 3 in the track 1 Will be located. In such a moving body system in which a force acts, if the component suction head or the like whose moving body 3 is a heavy object is mounted at the position shown in FIG. 1, the above-described twist of the track 1 is increased, and the height of the component suction head is increased. May deviate more than the desired height. When the moving body 3 is located near the center of the rail track 1 shown in FIG. 2, this twist becomes the largest, and the position of the head may be greatly displaced, which may hinder the work. Although it is conceivable that the mounting position of the head is provided in advance in consideration of twisting, such positional displacement due to twisting occurs when the moving body 3 is near the center of the track 1 and when it is at both ends of the track 1. The size is different. Therefore, the problem of misalignment cannot be solved.

  In order to suppress the twist that causes the deterioration of the positioning accuracy, it is conceivable to improve the rigidity of the track 1, but in this case, the track 1 becomes large and its weight also increases.

  The present invention has been made in consideration of the above circumstances, and can suppress deterioration in positioning accuracy caused by the weight of the rail track or the moving body without causing an increase in size and weight. An object is to provide a mobile system.

  In order to solve the above-described problem, a mobile system according to a first aspect of the present invention is provided with a track structure having a straight guide portion and a U-shaped cross-section, and is movable along the track structure. A moving body system having driving means for moving the moving body inside the track structure, wherein the moving body has an open lateral side in the track structure having a U-shaped cross section. And holding means for holding a load object on the opposite side of the opened side, the drive means is a linear motor, and the rail structure A secondary core is provided at least in part, and a primary core is provided at a position facing the secondary core in the moving body.

  Further, in the mobile body system according to claim 2, in the mobile body system according to claim 1, a first mobile body mechanism is configured by the track structure body, the mobile body, and the driving unit. The first moving body mechanism includes a second moving body mechanism that moves the first moving body mechanism in a direction orthogonal to a direction in which the linear guide portion extends.

  As described above, according to the present invention, it is possible to suppress deterioration in positioning accuracy due to the rail track or the weight of the moving body without causing an increase in size and an increase in weight.

It is sectional drawing which shows the main structures of the mobile body system using the conventional linear motor. It is a perspective view which shows schematic structure of the conventional mobile body system. It is a perspective view which shows schematic structure of the principal part of the mobile body system which concerns on one Embodiment of this invention. It is a perspective view which shows the main structures of the 1st mobile body mechanism which is a component of the said mobile body system which concerns on embodiment. It is sectional drawing which shows the main structures of the said 1st mobile body mechanism. It is a figure for demonstrating the principle of operation of the said 1st moving body mechanism. It is a perspective view which shows the structure of the principal part of the modification of the mobile body system which concerns on embodiment. It is sectional drawing which shows the structure of the principal part of the other modification of the mobile body system which concerns on embodiment. It is sectional drawing which shows the structure of the principal part of the other modification of the mobile body system which concerns on embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
A. Overall Configuration of Mobile System First, FIG. 3 is a perspective view showing a schematic configuration of main parts of a mobile system according to an embodiment of the present invention. As shown in the figure, this moving body system includes a first moving body having a track rail 30 laid in a straight line extending in the X-axis direction and a moving body 31 provided so as to be movable along the track rail 30. A mechanism 32 and a second moving body mechanism 33 that moves the first moving body mechanism 32 in the Y-axis direction orthogonal to the X-axis are provided.

  The second moving body mechanism 33 includes a ball screw 40 provided on each end of the track rail 30 and a motor 41 that drives the ball screw 40. Each ball screw 40 is provided with a moving gantry 42 that is moved in the Y-axis direction by the rotation of the ball screw 40, and both ends of the track rail 30 are fixed to each moving gantry 42. Thereby, the track rail 30 is moved in the Y-axis direction with the movement of the movable frame 42.

  Under this configuration, the motor 41 rotationally drives the ball screw 40 based on position information indicating the Y coordinate input from a control circuit (not shown), and moves to the position (Y coordinate) indicated by the position information. The track rail 30 fixed to 42 is moved. At this time, position information indicating the X coordinate is input to the first moving body mechanism 32 from a control circuit (not shown). In the first moving body mechanism 32 that has acquired this information, the moving body 31 is moved so as to be positioned at the position (X coordinate) indicated by the position information. In this moving body system, the moving body 31 can be moved to an arbitrary position in the XY plane in this way.

B. 1st moving body mechanism The 2nd moving body mechanism 33 in the moving body system mentioned above is a mechanism which drives the mobile stand 42 using the conventional general ball screw system, but this invention uses a linear motor as a drive system. The first moving body mechanism 32 is characterized, and the first moving body mechanism 32 will be described below with reference to FIGS. 4 and 5.

  As shown in FIG. 4, the first moving body mechanism 32 has the track rail 30 laid in a straight line along the X-axis direction as described above, and the moving body 31 is moved along the track rail 30. Has been made movable. As shown in FIG. 5, the track rail 30 is a U-shaped member whose side (left side in the figure) is open, and an end plate base that extends in the vertical direction on the opposite side (right side in the figure). Straight guide portions 53 are respectively provided above and below 30a. The moving body 31 is slidably supported by the linear guide portion 53, and the moving body 31 can move along the track rail 30.

  Further, the track rail 30 has a secondary core 52 that generates a magnetic field for applying thrust to the moving body 31 in cooperation with a magnetic field generating mechanism of the moving body 31 described later. Here, the secondary core 52 is supported in a state of being sandwiched between the end plate base 30a and the end plate 30b described above. That is, the secondary core 52 constitutes a part of the track rail 30 having a U-shaped cross section.

  The mobile body 31 is roughly composed of a main body 131 and a magnetic field generation mechanism 54. The main body 131 is a member having a substantially U-shaped cross section with the side (right side in the drawing) on the side of the moving body 31 open, and a base 131a extending in the vertical direction so as to cover the opening side of the moving body 31. The mounting part 131b extends from the upper and lower ends of the base part 131a to the moving body 31 side. Here, the attachment part 131b extends to the right side of the figure from the end plate base part 30a of the track rail 30, and the main body part 131 completely covers three sides of the track rail 30 except for the right side of the figure.

  The magnetic field generation mechanism 54 supports a primary core 57 provided at a position facing the above-described secondary core 52, a coil 58 wound around each primary core 57, and a primary core 57 around which the coil 58 is wound. The supporting member 59 is provided. The support member 59 is attached so as to extend from the center of the base portion 131a to the moving body 31 side, whereby the support member 59 is arranged between the two secondary cores 52. Therefore, the primary core 57 and the secondary side core 52 around which the coil 58 is wound are arranged at positions facing each other.

  Next, a specific drive configuration example of the moving body 31 by the magnetic field generation mechanism 54 and the secondary side core 52 constituting a part of the track rail 30 will be described with reference to FIG. In this embodiment, the secondary side core 52, the primary side core 57, and the coil 58 are provided in two sets with the support member 59 interposed therebetween, but both operate according to the same principle. The operation principle will be described.

  As shown in FIG. 6, tooth portions 52 a are formed at equal intervals along the longitudinal direction on the surface facing the primary core 57 of the secondary core 52 that constitutes a part of the track rail 30. The primary core 57 of the moving body 31 includes U-shaped A-phase iron core 70 and B-phase iron core 71, coils 58 a and 58 b wound around the A-phase magnetic pole 70 a and the phase magnetic pole 70 b of the A-phase iron core 70, and B Coils 58c and 58d wound around the B-phase magnetic pole 71a and the phase magnetic pole 71b of the phase iron core 71, and a permanent magnet 72 provided on the surface opposite to the secondary core 52 of the A-phase iron core 70 and the B-phase iron core 71. , 73 and a back plate 74 composed of a plate-like magnetic body attached to the permanent magnets 72, 73. Three pole teeth 75a are formed on the surface of the A-phase magnetic pole 70a facing the secondary side core 52 at the same pitch as the pitch P of the tooth portion 52a, and the same applies to the other magnetic poles 70b, 71a, 71b. Three pole teeth 76b, 77a, and 77b are formed on each other. Further, the magnetic poles 70b, 71a, 71b are sequentially shifted by P / 4 with respect to the A-phase magnetic pole 70a, so that the magnetic poles 70b, 71a, 71b have a positional relationship in which the phases are different from each other by 90 °. Yes. Under such a configuration, a pulse signal is supplied to the coils 58a, 58b, 58c, and 58d by a one-phase excitation method or the like, thereby sequentially generating magnetic fluxes in the coils 58a, 58b, 58c, and 58d, and the permanent magnets 72 and 73. The magnetically generated position of the moving body 31 with respect to the secondary core 52 is sequentially moved at each magnetic pole 70a, 70b, 71a, 71b. It is moved in the direction along. This is a configuration of a general linear pulse motor, but other than this, for example, a linear pulse motor system described in Japanese Patent Laid-Open No. 3-124259 may be used.

  Returning to FIG. 5, the component suction head (load object) 132 is attached to the distal end portion 131 c of the attachment portion 131 b of the main body portion 131 described above. Shall be shown. When the linear motor having such a structure moves a work robot in a semiconductor factory, a counterclockwise moment in FIG. 5 acts on the starting rail 30 due to its own weight, that is, twisting occurs. The torsional shear center S generated in the U-shaped member is located on the right side of the end plate base 30a as shown in the figure. In the present embodiment, the moving body 31 mounts the component suction head 132 on the shear center S. In other words, in order to match the shear center S of the track rail 30 and the mounting position of the component suction head 132, the main body 131 that holds the component suction head 132 in the shape as described above and at the position as described above is designed. It is doing. That is, in the case where the track rail 30 having a U-shaped cross section is used as in the present embodiment, it is considered that the shear center S is located on the back side (right side in FIG. 5) of the end plate base 30a. The head 132 is held on the back side of the end plate base 30a.

  In a semiconductor manufacturing facility or the like, high positional accuracy is required in a system that moves an apparatus for transporting and mounting semiconductor components. Even when the driving control of the moving body is performed precisely, position fluctuations due to mechanical causes such as torsion of the track rail as described above may occur. In a semiconductor manufacturing facility, not only drive control but also a mechanical position change may cause a decrease in product yield. The mobile body system according to the present embodiment can suppress the positional fluctuation caused by the torsion due to the weight of such a member, and is suitable as a mobile body system used in semiconductor manufacturing equipment that requires high positional accuracy. It provides a system.

  By the way, in the mobile system as shown in FIG. 1, it is also conceivable to improve the rigidity of the track 1 and suppress the mechanical displacement due to the twist as described above. However, in this case, the weight of the track 1 is significantly increased. On the other hand, in the mobile body system according to the present embodiment, the mobile body 31 has the shape as described above, and the configuration is such that the component suction head 132 is held on the back side of the end plate base 30a. By matching, the above twist is suppressed. Therefore, it is possible to suppress misalignment without causing a significant increase in weight.

  Further, in the system in which the second moving body mechanism 33 moves the first moving body mechanism 32 as in the present embodiment, an increase in the weight of the first moving body mechanism 32 is required for the second moving body mechanism 33. Power-will increase. If the weight increase can be suppressed as in the first moving body mechanism 32 of the present embodiment, the second moving body mechanism 33 can be compared with a conventional system that suppresses torsion by improving the rigidity of the member. A motor having a low capacity can be used as the motor 41, and an increase in system size and an increase in power consumption can be suppressed. Moreover, since the driving force of the 2nd mobile body mechanism 33 can be made small, a vibration and noise can also be suppressed.

  Further, in the present embodiment, as shown in FIG. 5, the linear guide portion 53 is disposed on the neutral axis of the rail track 30 having a U-shaped cross section to support the moving body 31. The effect by this is demonstrated. In the system in which the moving body travels along the track such as the linear motor according to the present embodiment, when the moving body travels at a high speed, heat is generated due to a seal resistance or the like. Thus, the linear guide 53 generates heat during traveling of the moving body, and the heat is transmitted to the rail track 30. The rail track 30 due to such heat generation is mechanically deformed due to the bimetal effect and is curved. If the rail track 30 is deformed in this way, the position of the movable body 31 guided and supported by the rail track 30 may occur, which may hinder the semiconductor manufacturing process and the like. By the way, since the bimetal effect mentioned above produces a deformation | transformation centering on a neutral axis | shaft, the deformation amount on a neutral axis becomes small. In the present embodiment, paying attention to this principle, the linear guide portion 53 that supports the moving body 31 is provided on the neutral axis with little deformation, thereby suppressing the displacement of the moving body 31.

C. Modifications The present invention is not limited to the above-described embodiments, and various modifications as described below are possible.

(1) In the above-described embodiment, the moving body 31 is driven by the linear motor. However, the present invention is not limited to this, and the moving body 31 may be driven by another method. For example, a drive system using a ball screw 70 as shown in FIG. 7 or a system in which the moving body 31 is driven by a belt drive such as a timing belt may be used. In the above-described embodiment, the linear pulse motor is used as the driving method of the first moving body mechanism 32. However, the present invention is not limited to this, and is applicable to a moving body system using other types of linear motors such as an induction type. It is also possible to do. Further, even in a system using a linear pulse motor, the configuration is not limited to the above-described configuration in which the core, the coil, and the like are arranged above and below the support member 59. For example, the linear motor has a configuration as shown in FIG. May be. Even in such a case, similarly to the above-described embodiment, the moving body 31 may hold a heavy object such as a component suction head near the shear center S of the rail track 30 having a U-shaped cross section.

(2) In the above-described embodiment, the linear guide portion 53 is provided on the neutral axis of the rail track 30 to suppress the positional displacement of the moving body 31 due to the thermal deformation described above. If there is a problem such as a narrow space, a straight guide portion 53 may be provided on the end plate 30b of the rail track 30 to support the moving body 31, as shown in FIG. Also in this case, similarly to the above-described embodiment, it is possible to suppress the positional deviation caused by the twist due to the weight of the rail track 30, the moving body 31, the component suction head 132, and the like.

DESCRIPTION OF SYMBOLS 30 ... Track rail, 30a ... End plate base, 31 ... Moving body, 32 ... 1st moving body mechanism, 33 ... 2nd moving body mechanism, 52 ... Secondary side core, 53 ... Linear guide part, 54 ... Magnetic field generation mechanism , 70 ... Ball screw, 131 ... Main body part, 131a ... Base part, 131b ... Mounting part, 132 ... Component adsorption head, S ... Shear center

Claims (2)

A driving means for moving the moving body into the track structure, the track structure having a U-shaped cross section having a linear guide portion; and a moving body provided to be movable along the track structure. A mobile system comprising:
The moving body is provided so as to cover three sides except the opposite side of the open side in the track structure having a U-shaped cross section, and holds the load object on the opposite side of the open side. Holding means,
The driving means is a linear motor,
A mobile body system, wherein a secondary side core is provided in at least a part of the rail structure, and a primary side core is provided at a position facing the secondary side core in the mobile body. A first moving body mechanism is configured by the track structure, the moving body, and the driving means,
The mobile system according to claim 1, further comprising: a second mobile mechanism that moves the first mobile mechanism in a direction orthogonal to a direction in which the linear guide portion extends.

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