JP6499756B2 - Substrate holding device - Google Patents

Description

  The present invention relates to a substrate holding apparatus that holds a substrate such as a circuit board for performing operations on the substrate.

  For example, when an electronic component is mounted on a circuit board, a board holding device is used as an apparatus for fixing and holding the circuit board. The substrate holding device holds the substrate with a certain holding force, and it is desired that the holding force be appropriate. In the substrate holding apparatus described in the following patent document, the thickness of the substrate is determined, and the holding force is made constant regardless of the thickness.

JP2000-124687

Problems to be Solved by the Invention

  The holding force when holding the substrate in the substrate holding device has an appropriate size depending on the size, shape, rigidity, etc. of the substrate and the type of work on the substrate, and if the holding force can be changed, The practicality of the substrate holding device is improved. The present invention has been made in view of such circumstances, and an object thereof is to provide a highly practical substrate holding device.

In order to solve the above problems, the substrate holding device of the present invention is
A table disposed below the substrate, a lifting mechanism for raising and lowering the table, a support column which is erected on the table and whose upper end can be displaced vertically with respect to the table, and an upper end of the support column An elastic body for applying an urging force in a direction in which the portion is displaced upward to the support column, and a pair of stoppers for locking both ends in the width direction of the substrate from above,
The substrate is lifted through the support columns by raising the table, and the both ends of the substrate are moved to the pair in a state where the upper ends of the support columns are displaced downward against the urging force of the elastic body. A substrate holding device that holds the substrate by applying a holding force corresponding to the urging force of the elastic body to the substrate by being locked to the stopper,
By controlling the rising position of the table, the holding force applied to the substrate can be arbitrarily changed ,
further,
A plurality of support pillars each serving as the support pillar;
A support plate supported by the upper end portions of the plurality of support pillars, the upper surface contacting the lower surface of the substrate and supporting the substrate;
It is provided with.

  According to the substrate holding device of the present invention, since the holding force applied to the substrate can be arbitrarily changed by a simple means of controlling the raised position of the table, the substrate holding device of the present invention is highly practical. .

It is a perspective view which shows the component mounting system comprised by the component mounting machine by which the board | substrate holding | maintenance apparatus of an Example is employ | adopted. It is a perspective view which shows schematic structure of the component mounting machine which comprises the component mounting system of FIG. It is a perspective view which shows schematic structure of another component mounting machine which comprises the component mounting system of FIG. It is a perspective view which shows the board | substrate holding | maintenance apparatus employ | adopted as the component mounting machine of FIG. 2, FIG. FIG. 5 is a cross-sectional view for explaining the operation of the substrate holding device of FIG. 4. It is a perspective view which shows the board | substrate holding | maintenance apparatus of the Example with which the raising unit was attached. It is sectional drawing for demonstrating operation | movement of the board | substrate holding | maintenance apparatus of FIG. It is sectional drawing for demonstrating the modification regarding the support pillar in a board | substrate holding | maintenance apparatus.

  Hereinafter, a representative embodiment of the present invention will be described in detail with reference to the drawings as an example of a substrate holding device employed in a component mounting machine. Incidentally, in the description of the following embodiment, first, the component mounting machine will be described, and then the embodiment of the present invention will be described. It should be noted that the present invention can be implemented in various modes in which various changes and improvements are made based on the knowledge of those skilled in the art, in addition to the following examples.

[A] Configuration of the substrate mounting system and the component mounting machine A component mounting machine in which the substrate holding apparatus of the embodiment is employed constitutes, for example, the component mounting system shown in FIG. The component mounting system mounts an electronic component (hereinafter simply referred to as “component”) on a circuit board (which is a kind of “board”, and may be simply referred to as “substrate” hereinafter). The system includes three component mounting machines 10 and 12. In the figure, if the left back is the upstream side, the right front is the downstream side, the left front is the front side, and the right back is the rear side, in this component mounting system, the two component mounting machines 10 are on the downstream side. In addition, one component mounting machine 12 having a relatively wide width is disposed in close contact with each other on the two system bases 14 arranged side by side.

  The substrate is transported through the component mounting machines 10 and 12 from the upstream side toward the downstream side, that is, in the direction in which the substrate is transported (hereinafter sometimes referred to as “transport direction”). The component mounting operation by the component mounting machines 10 and 12 is performed on the board, and the mounting of the component on the board is completed. By sequentially transporting the plurality of boards in the transport direction in the system, component mounting on each of the plurality of boards is completed sequentially. The component mounting system includes, for example, a solder printer that prints cream solder on a substrate, an inspection device that inspects the results of work performed by the solder printer and the component mounting devices 10 and 12, and a component that is melted on the substrate. Along with a fixed reflow furnace and the like, it is arranged on an electronic circuit production line.

  The two component mounting machines 10 arranged on the upstream side have the same configuration as each other, and are arranged side by side on one system base 14 as shown in FIG. Explaining with reference to the illustration of the component mounting machine 10 on the downstream side with the exterior panel removed, each component mounting machine 10 includes a base 16, frames 18 and 20 erected on the base 16 before and after, And the beam 22 overlaid on the frames 18 and 20, and the housing of the component mounting machine 10 is configured by them.

  A substrate holding device 24 that can be the substrate holding device of the embodiment is disposed on the base 16. Although the configuration of the substrate holding device 24 will be described later, the substrate holding device 24 has not only a function of fixing and holding the substrate at the set work position, but also a function of carrying the substrate from the upstream side and carrying it out to the downstream side. Have. That is, the substrate holding device 24 also functions as a substrate transfer device. Incidentally, FIG. 1 shows a state in which the substrate S is fixedly held at the working position by the substrate holding device 24.

  On the front side of the substrate holding device 24, a plurality of component feeders 26 each functioning as a component supply device are arranged side by side. Incidentally, each of the component feeders 26 is a so-called tape feeder. On the other hand, a component mounting device 28 is supported on the beam 22. The component mounting device 28 includes a mounting head 30 and an XY robot type head moving device 32 that moves the mounting head 30 back and forth and from side to side. The mounting head 30 includes a plurality of suction nozzles as component holders for sucking and holding components at the lower end portion, and has a nozzle lifting mechanism for lifting and lowering one of the suction nozzles.

  A component mounting operation is performed by the component mounting device 28 on the substrate fixed at the work position by the substrate holding device 24. In the component mounting operation, the mounting head 30 is moved above the component feeder 26 to suck and hold the component by the suction nozzle, and then the mounting head 30 is moved above the substrate and held by the suction nozzle. The mounted component is placed on the upper surface of the substrate.

  The component mounting machine 12 arranged on the downstream side is arranged on one system base 14, and the component mounting machine 12 is sized in the transport direction as can be seen from FIG. A large base 34 and frames 36 and 38 are included. And in the component mounting machine 12, the same two board | substrate holding | maintenance apparatuses 24 arrange | positioned in the component mounting machine 10 are arrange | positioned along with the conveyance direction. The two substrate holding devices 24 are configured to transport one substrate in cooperation with each other, and the above-described working positions are set in both of the two substrate holding devices 24. The component mounting device 40 of the component mounting machine 12 includes the head moving device 42 in which the range of movement of the mounting head 30 in the transport direction is increased, so that the component mounting device 40 is more in the transport direction than the component mounting device 28 of the component mounting machine 10. The mounting head 30 can be largely moved. With such a configuration, the component mounting machine 12 can execute the component mounting work at any of the two work positions. Specifically, the component mounting machine 12 can perform the same component mounting operation on two stages.

[B] Configuration and Function of Substrate Holding Device As shown in FIG. 4, the substrate holding device 24 includes a base plate 50 and both ends in a direction perpendicular to the transport direction of the base plate 50, that is, an end on the front side. And a pair of generally frame-like support frames 52 and 54 erected at the rear end. The support frames 52 and 54 are generally gate-shaped and function as a pair of side plates facing each other with the substrate interposed therebetween. The front support frame 52 is fixed to the base plate 50, while the rear support frame 54 moves in the front-rear direction along a pair of guide rails 56 arranged side by side on the base plate 50. It is possible. The rear support frame 54 is moved back and forth according to the width in the front-rear direction of the substrate to be held and transported by a moving mechanism 60 including a motor 58 as a drive source. The moving mechanism 60 is configured to include a ball screw mechanism, as can be seen from the drawing.

  In each of the support frames 52 and 54, a pair of pulleys 62 are rotatably supported on their inner surfaces (surfaces facing each other). One of the pair of pulleys 62 is disposed at the upstream end in the conveying direction of the support frame 52 (54), and the other is disposed at the downstream end. A pair of pulleys 62 are wound around a conveyor belt 64, and the pair of conveyor belts 64 are held by a pair of support frames 52 and 54, respectively, so as to be able to turn. The downstream side of the pair of pulleys 62 is rotated by a rotating mechanism 68 including a motor 66 as a drive source and a gear train, and the conveyor belt 64 circulates by the rotation. Yes. That is, the substrate holding device 24 includes a pair of conveyor belts 64, and the substrate is supported by the pair of conveyor belts 64 when both ends of the substrate in the front-rear direction are placed on the pair of conveyor belts 64. The pair of conveyor belts 64 circulate in a state where both ends of the substrate are supported, so that the substrate is transported in the transport direction.

  Each of the support frames 52 and 54 has a substrate placed on the pair of conveyor belts 64 between the pair of conveyor belts 64, more specifically, in the vicinity of the conveyor belt 64 supported by each. The support bar 70 is supported so as to be movable up and down. Incidentally, in FIG. 4, a part of the support bar 70 supported by the support frame 54 on the rear side is omitted. The support bar 70 extends along the support frame 52 (54) in the transport direction, and each of both ends extends to the outside of the support frame 52 (54) in the transport direction, and the outer surface (surface facing away from each other). It is supposed to wrap around. A nut 72 is held non-rotatably at each of both ends. On the other hand, each of the support frames 52 and 54 is provided with a pair of motors 74 at both ends of the outer surface in the transport direction, and the axis of rotation of each of the pair of motors 74 is up and down. The posture is extended in the direction, and the screw rod 76 is used. Each screw rod 76 is screwed with a nut 72 held at each end of the support bar 70, and a pair of nuts 72 and a pair of screw rods 76 constitute a pair of screw mechanisms 78. -ing As is apparent from the above structure, one support bar 70 is moved up and down by the rotation of the pair of motors 74. That is, a support bar elevating mechanism that includes the pair of screw mechanisms 78 and a pair of motors 74 as a drive source to elevate and lower one support bar 70 that is the support is configured.

  Furthermore, a stopper 80 extending along the transport direction is attached to the upper end of each of the support frames 52 and 54. As will be described in detail later, the substrate lifted by the support bar 70 is in a state in which both ends in the direction perpendicular to the conveyance direction thereof, that is, both ends in the width direction are sandwiched between the support bar 70 and the stopper 80. Held in. The two stoppers 80 making a pair are fastened to the support frames 52 and 54 by bolts 82, respectively, and can be replaced with other types of stoppers as will be described later.

  On the other hand, a table 84 is disposed between the support frames 52 and 54. The table 84 is moved up and down by a table lifting mechanism 86. Referring to FIG. 5 as well, the table elevating mechanism 86 includes four jacks 88 provided at four corners of the table 84, a timing belt 90 for operating the four jacks 88 in synchronization, It includes a lifting motor 92 that operates four jacks 88 by driving the timing belt 90. Each jack 88 includes a base body 94, a nut 96 rotatably held by the base body 94, and a screw rod 98 that is screwed into the nut 96. The upper end of the screw rod 98 of each jack 88 is fixed to the lower surface of the table 84. The nut 96 has a portion that functions as a pulley on the outer periphery, and the motor shaft of the elevating motor 92 also has a portion that functions as a pulley on the outer periphery, and the timing belt 90 is wound around these portions. It is hung. As the lifting motor 92 rotates, the nuts 96 of the four jacks 88 rotate synchronously, and the screw rod 98 is moved up and down, so that the table 84 is lifted and lowered.

  An encoder 100 is attached to the lifting motor 92 so that the rotational position of the motor shaft, that is, the amount of rotation of the lifting motor 92 can be grasped. As is the case with the control of the support bar lifting mechanism described above, the control of the table lifting mechanism 86 is performed by the control device 102 (see FIG. 1) integrated with the operation panel that controls the entire component mounting machines 10 and 12. ). Based on the signal from the encoder 100, the control device 102 can grasp the lift position (position in the vertical direction) of the table 84 and control the table lift mechanism 86 based on the lift position.

  As shown in FIGS. 4 and 5, a backup pin 104 can be erected on the table 84. The table 84 has a plurality of attachment holes 106 each of which is a screw hole, and the backup pin 104 can be attached to any of the plurality of attachment holes 106. That is, the backup pin 104 can be erected at an arbitrary position corresponding to the plurality of mounting holes 106.

  Referring to FIG. 5, the operation of the substrate holding device 24 will be described. As shown in FIG. 5A, the substrate S is supported in a state where both ends thereof are supported by a pair of conveyor belts 64. The pair of conveyor belts 64 are conveyed by being rotated and stopped at a predetermined work position. In a state where the substrate S is positioned at the working position, as shown in FIG. 5B, by driving each motor 74, the pair of support bars 70 is raised, and the pair of support bars The bar 70 lifts the substrate S. The substrate S is lifted until both ends are locked by the pair of stoppers 80, and each of the both ends is fixed and held with the stopper 80 and the support bar 70 sandwiched therebetween. The holding force at this time is a force for holding the substrate S between the stopper 80 and the support bar 70 and is generated by the force of the motor 74. This force is considerably large, but is constant because the force of the motor 74 is not controlled.

  Next, as shown in FIG. 5B, the table 84 disposed below the substrate S is raised to a predetermined raised position by the table lifting mechanism 86. The ascending position at this time is a position where the upper end of the backup pin 104 is in contact with the lower surface of the substrate S. In this state, the component mounting operation of the substrate S is performed. The backup pin 104 is mounted, for example, so that the substrate S does not bend downward due to its own weight in the component mounting operation. In order to prevent the substrate S from being greatly bent downward due to the force applied to the substrate S from above, it plays a role of supporting the substrate S and substantially generates the above-mentioned holding force. Absent.

[C] Substrate holding device to which the substrate support unit is attached. For example, when the substrate has a relatively low rigidity such as a relatively thin substrate, even if the substrate is supported by the backup pin 104, for example, the backup pin. It is also expected that the bending at the portion where 104 does not contact is increased, or that the deformation to the extent of damage is caused in the substrate during the component mounting operation. In other words, depending on the backup pin, it may be difficult to hold the component in a state suitable for component mounting work. Although this is an example, in order to ensure holding in a state suitable for component mounting work, the board holding device 24 replaces the backup pin 104 with a board support unit 110 as shown in FIG. It can be attached to the upper surface of the table 84. The substrate holding device 24 to which the substrate support unit 110 is attached becomes the substrate holding device of the embodiment.

  Referring also to FIG. 7, the substrate support unit 110 includes a base plate 112 fastened to the table 84, a pair of rectangular beams 114 disposed above the base plate 112, and the 1 The top plate 116 is supported by the pair of beams 114 so as to be movable in the vertical direction. The base plate 112 is fastened to the table 84 by bolts 118 using the mounting holes 106 provided in the table 84.

  The pair of beams 114 are extended in a direction perpendicular to the transport direction at both ends in the substrate transport direction, with the block-shaped spacer 120 sandwiched between the base plate 112 and the base plate. 112 is fixed. Each end of each beam 114 is provided with a through hole 124 into which a bush 122 is fitted, and a support column 126 is inserted into each through hole 124. That is, a total of four support pillars 126 are provided at the four corners of the top plate 116.

  Each support column 126 is movable up and down with respect to the beam 114, and the upper end is fixed to the lower surface of the top plate 116. That is, the top plate 116 is supported by the upper ends of each of the four support columns 126. On the other hand, a locking ring 128 is fixed to the lower end of each support column 126, and movement beyond a certain position above each support column 126 is prohibited. On the other hand, a spring 130 that is a compression coil spring is disposed in the vicinity of each support column 126, and the top plate 116 is urged upward by the spring 130. Due to the action of the spring 130 and the locking ring 128, the top plate 116 is maintained at a predetermined position with respect to the table 84, that is, the position shown in FIG. The At this position, the distance between the top plate 116 and the beam 114, that is, the length of the spring 130 is "L" as shown in the drawing.

  The table 84 and the pair of beams 114 have a fixed position, and the pair of beams 114 can be considered as a part of the table 84. Based on this idea, in the substrate holding device 24, the support column 126 is erected on the table 84, and the upper end portion fixed to the top plate 116 can be displaced in the vertical direction with respect to the table 84. It has been done. The spring 130 functions as an elastic body that applies an urging force in the direction in which the upper end portion of the support column 126 is displaced upward to the support column 126.

  The operation of the substrate holding device 24 provided with the substrate support unit 110 will be described with reference to FIG. 7B. In the substrate holding device 24, the substrate holding device 24 is transported by the conveyor belt 64 and positioned at a predetermined work position. The substrate S thus held is held by the substrate holding device 24 when the table 84 is raised by the table elevating mechanism 86. Incidentally, when the substrate support unit 110 is provided, the support bar 70 is not operated.

  As the table 84 is raised, the substrate support unit 110 is lifted, and the substrate S is lifted in a state where the upper surface of the top plate 116 is in contact with the lower surface of the substrate S. In other words, the substrate S is lifted through the support pillar 126. In the substrate holding device 24, the pair of stoppers 80 described above are replaced with another pair of stoppers 140 having different dimensions in the direction perpendicular to the transport direction of the substrate S, that is, in the width direction. More specifically, it is changed to another pair of stoppers 140 in which the dimension in the width direction of the region for locking both ends of the substrate S is increased. Therefore, when the table 84 is raised to a certain position, both ends of the substrate S are locked by the pair of stoppers 140, and both ends of the substrate S are sandwiched between the top plate 116 and the stopper 140. It becomes a state.

  When the table 84 is further raised, the top plate 116 is lowered with respect to the table 84 against the urging force of the spring 130. The holding force applied to the substrate S is the force at which the both ends of the substrate S are clamped by the top plate 116 and the pair of stoppers 140. This holding force corresponds to the length L of the spring 130 immediately after sandwiching the substrate S. As the table 84 further rises, the holding force increases as the distance between the top plate 116 and the table 84, that is, the distance between the upper end of the support column 126 and the beam 114 decreases. That is, the upper end portion of the support column 126 is displaced downward against the urging force of the spring 130. The holding force at that time has a magnitude corresponding to the length L ′ <L of the spring 130. Utilizing this fact, in the substrate holding device 24, the holding force applied to the substrate S is arbitrarily changed by controlling the raised position of the table 84. As a result, in the substrate holding device 24, an appropriate holding force can be applied to the substrate according to the substrate.

  In the substrate holding device 24 shown in FIGS. 6 and 7, the holding force acts on the substrate by sandwiching both ends of the substrate between the top plate 116 and the stopper 140. Therefore, the holding force does not act on the central portion of the substrate S, and no force that bends the substrate by holding the substrate. The substrate is supported so that the upper surface of the top plate 116 is in close contact with the lower surface of the substrate. For this reason, during the component mounting operation, the force that bends the substrate due to component mounting does not act on the substrate. The top plate 116 is supported by the upper ends of the plurality of support pillars 126 and functions as a support plate that supports the substrate with its upper surface contacting the lower surface of the substrate.

  The substrate holding device 24 can hold substrates having various widths, and the stopper 80 can be changed to those having various widths according to the substrates. As a result, even if the width of the substrate changes, a state in which both end portions are sandwiched between the stopper and the top plate 116 can be easily realized. More specifically, for example, a jig (carrier) that sandwiches a substrate between a pair of frame-like plates (frames) is used, and the substrate is transported together with the jig by the substrate holding device 24. The case where it hold | maintains via a tool is also considered. Even in such a case, when the substrate is not sandwiched between the top plate 116 and the stopper 80 via the jig, a force for deforming the jig acts on the jig itself, and the substrate is bent by the force. A strange situation is also expected. The ability to change the stopper 80 to various widths can be an effective means from the viewpoint of proper holding of the substrate even in such a case.

[D] Modification
i) Modification Regarding Support Pillar In place of the substrate support unit 110 having the above structure, for example, a substrate support unit having the structure shown in FIG. 8 can be adopted. FIG. 8 shows one support column 150 constituting the substrate support unit and the vicinity thereof. This substrate support unit has a structure in which a plurality of support columns 150 are interposed between a base plate 112 and a top plate 116. The support column 150 includes a base body 152 fixed to the base plate 112 and pins 154 held on the base body 152 so as to be movable up and down. An upper end portion of the pin 154 is fixed to the lower surface of the top plate 116, and a lower portion is inserted into a holding hole 156 provided in the base body 152. That is, the support column 150 is a telescopic support column whose upper end can be displaced up and down.

  A spring 158 that is a compression coil spring is interposed between the lower surface of the top plate 116 and the upper end surface of the base body 152. The spring 158 may be considered as an elastic body that applies an upward urging force to the top plate 116, that is, an elastic body that applies an urging force in the direction in which the upper end portion of the support column 150 is displaced upward to the support column 150 itself. it can. On the other hand, the lower portion of the holding hole 156 has a larger inner diameter, and the holding hole 156 has a step surface 160. A locking ring 162 is fixed to the lower end of the pin 154, and movement beyond a certain position above the pin 154 is prohibited. As long as no other force is applied, the support column 150 is maintained at a predetermined length by the action of the spring 158 and the locking ring 162.

  In the substrate holding device 24 in which the substrate support unit configured to include the support column 150 as described above is disposed, when the substrate is held, the support column 150 contracts as shown by a two-dot chain line in the figure. The plate 116 is displaced downward, and a holding force corresponding to the length of the support column 150 is generated in the same manner as the substrate holding device 24 described above. Similarly, the holding force can be changed to an arbitrary magnitude by controlling the raised position of the table 84.

ii) Modification with regard to locking by stopper and presence / absence of top plate In the substrate holding device 24 described above, the substrate is held in a state where both ends of the substrate are held between the stopper 140 and the top plate 116. For example, when the rigidity of the substrate is relatively high, it is not always necessary to hold both ends of the substrate. In other words, in the substrate holding device 24 shown in FIG. 7, the stopper 80 is employed instead of the stopper 140. In that case, when the substrate is held, a force that bends the substrate acts on the substrate. However, when the rigidity of the substrate is high, the holding force can be arbitrarily changed, so Holding is possible.

  In the substrate holding device 24 described above, the substrate support unit 110 having the top plate 116 is employed. When the rigidity of the substrate is relatively high, the top plate 116 is not necessarily required. That is, a telescopic support column with a built-in spring may be erected on the table 84. In other words, the backup pin 104 is changed to a telescopic type in the substrate holding device 24 shown in FIGS. Even such a substrate holding apparatus can appropriately hold the substrate by utilizing the fact that the holding force can be arbitrarily changed.

iii) Others The substrate holding device 24 is a substrate holding device adopted in a component mounting machine for mounting an electronic component on a circuit board, but the substrate holding device of the present invention is limited to that used in a component mounting machine. Instead, it may be employed in various devices.

  24: Substrate holding device 50: Base plate 52: Support frame [side plate] 54: Support frame [side plate] 62: Pulley 64: Conveyor belt 70: Support bar 80: Stopper 84: Table 86: Table lifting mechanism 92: Lifting motor 100 : Encoder 102: Control device 104: Backup pin 110: Substrate support unit 112: Base plate 114: Beam 116: Top plate [support plate] 126: Support column 130: Spring [elastic body] 140: Stopper 150: Support column S: Substrate L, L ': Spring length

Claims (4)

A table disposed below the substrate, a lifting mechanism for raising and lowering the table, a support column which is erected on the table and whose upper end can be displaced vertically with respect to the table, and an upper end of the support column An elastic body for applying an urging force in a direction in which the portion is displaced upward to the support column, and a pair of stoppers for locking both ends in the width direction of the substrate from above,
The substrate is lifted through the support columns by raising the table, and the both ends of the substrate are moved to the pair in a state where the upper ends of the support columns are displaced downward against the urging force of the elastic body. A substrate holding device that holds the substrate by applying a holding force corresponding to the urging force of the elastic body to the substrate by being locked to the stopper,
By controlling the rising position of the table, the holding force applied to the substrate can be arbitrarily changed ,
further,
A plurality of support pillars each serving as the support pillar;
A support plate supported by the upper end portions of the plurality of support pillars, the upper surface contacting the lower surface of the substrate and supporting the substrate;
Substrate holding apparatus comprising a. The substrate holding apparatus according to claim 1 , wherein each of the both end portions of the substrate is sandwiched between the support plate and each of the pair of stoppers in a state where the substrate is held. The substrate holding device is
A pair of side plates facing each other with a substrate interposed therebetween, and a pair of conveyor belts held by the pair of side plates so as to be able to circulate, respectively, with the both ends supported by the pair of conveyor belts. It also functions as a substrate transport device that transports
3. The substrate holding apparatus according to claim 1 , wherein the pair of stoppers are provided on the pair of side plates so that the pair of stoppers are respectively positioned above the pair of conveyor belts. Said pair of stopper, any one of claims 1 dimensions is interchangeably structure different another pair of stoppers with each other in the width direction of the region for locking the both end portions of the substrate according to claim 3 A substrate holding apparatus according to the above.

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