JP2010158871A - Printing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a printing apparatus which positions a substrate in relation to a mask horizontally sustained by a substrate delivery means and prints paste on the upper surface of the substrate via through-holes formed on the mask by overlapping on the bottom surface of the mask. <P>SOLUTION: Five shaft members 231a to 231e are movably provided within the horizontal plane (XY Plane) and a movable plate 21 is pivotally supported by these shaft members 231a to 231e. Therefore, the movable plate 21 is movable within the horizontal plane and also rotatable in relation to the vertical axis. The shaft member 231a is driven in the direction of the axis X1, and the shaft member 231d is driven in the direction of the axis X2 (in the extended direction of the guide rail 234d) for moving the movable plate 21 within the horizontal plane (XY Plane) and rotating in relation to the vertical axis, thereby positioning the substrate 1 in relation to the mask 51. Thus, the X-R shaft drive unit 23 conducts the relative position adjustment of the substrate 1 in relation to the mask 51. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a printing apparatus that superimposes a substrate on a mask and prints a paste on the substrate through a through-hole formed in the mask.

  2. Description of the Related Art Conventionally, printing apparatuses that print paste such as cream solder on a substrate using a mask in which a thin plate-like stencil is attached to the lower surface side of a mask frame (mask frame) are widely known. In this type of printing apparatus, it is necessary to transport the substrate to the lower surface side of the mask and to position the substrate with high accuracy with respect to the mask. Further, it is necessary to move the substrate to a position immediately below the lower surface of the mask while being positioned. Therefore, for example, as described in Patent Document 1, a substrate transport unit (positioning unit) that transports a substrate in the X-axis direction, the Y-axis direction, the θ-axis direction, the first Z-axis direction, and the second Z-axis direction. ) Is provided.

JP 2008-142949 A (FIG. 1)

  In the substrate transport means provided in the apparatus described in Patent Document 1, the Y-axis table, the X-axis table, and the θ-axis table are stacked in the vertical direction in order to move the substrate in the above-described 5-axis direction. On top of this, a first Z-axis table and a second Z-axis table are combined. For this reason, the substrate transfer means becomes higher in the vertical direction, which is one of the main factors for increasing the size of the apparatus.

  The present invention has been made in view of the above problems, and the substrate is positioned with respect to the mask held in a horizontal state by the substrate transport means, and the through-hole formed in the mask is superimposed on the lower surface of the mask. An object of the present invention is to reduce the size of a printing apparatus that prints paste on the upper surface of a substrate.

  The present invention relates to a printing apparatus for positioning a substrate by a substrate transport unit with respect to a mask held in a horizontal state, overlaying the substrate on a lower surface of the mask, and printing a paste on the upper surface of the substrate through a through-hole formed in the mask. In order to achieve the above object, the substrate transport means is capable of moving in a horizontal plane while supporting the substrate support unit and holding the substrate, and is rotatable about the vertical axis. A movable member; and a first drive unit that moves the movable member two-dimensionally in a horizontal plane and rotates the vertical member relative to a vertical axis to adjust a relative position of the substrate with respect to the mask. Three or more shaft members that are movable two-dimensionally in a horizontal plane while pivotally supporting the shaft, and a first shaft drive unit that drives the first shaft member of the shaft members in the first horizontal direction It is characterized by having a second axis drive unit for driving the second shaft member of the shaft member in a first horizontal direction.

  In the invention configured as described above, three or more shaft members that are two-dimensionally movable in a horizontal plane are provided, and the first shaft member of these shaft members is provided by the first shaft drive unit. The second shaft members are each driven in the first horizontal direction by the second shaft drive unit. Further, the movable member is pivotally supported by these shaft members so that the movable member can move in the horizontal plane and can rotate with respect to the vertical axis. Therefore, the movable member is moved two-dimensionally in the horizontal plane by driving the first shaft member and the second shaft member and rotated with respect to the vertical axis, whereby the substrate supported by the substrate support unit is moved relative to the mask. The relative position of the substrate with respect to the mask is adjusted. Thus, in the present invention, the relative position of the substrate with respect to the mask is adjusted by one drive unit.

  Further, a second drive unit for moving the movable member in the second horizontal direction is further provided, and the movable member is moved between the lower position of the mask and the position away from the lower position by the second drive unit. Also good. Thereby, various operations such as loading / unloading of the substrate and imaging of fiducial marks formed on the upper surface of the substrate can be performed at a position separated from the lower position of the mask in the second horizontal direction.

  Also, in order to raise the substrate supported by the substrate support unit toward the lower surface of the mask and overlap the mask, the substrate support unit is moved up and down between the movable member and the substrate support unit in the same manner as in the conventional apparatus. The third drive unit may be provided, but in this case, the substrate transfer means becomes higher in the vertical direction, leading to an increase in the size of the apparatus. However, an increase in size of the apparatus can be effectively suppressed by configuring as follows. That is, the movable member is slidably supported by the middle portion of the shaft member extending in the vertical direction so that the movable member can be moved up and down in the vertical direction, and the third drive unit is attached to the upper end portion of the shaft member. And a lifting / lowering drive unit that moves the movable member along the shaft member below the shaft support member. By providing the drive unit so as to hang from the tip end side of the shaft member in this way, an increase in the size of the device in the vertical direction is prevented.

  By the way, in the present invention, the first shaft member and the second shaft member are driven and displaced in the first horizontal direction by the first shaft driver and the second shaft driver, respectively. Therefore, the movable member pivotally supported by the shaft member does not simply move in the first horizontal direction, but involves a two-dimensional movement operation in the horizontal plane and a rotation operation around the vertical axis as will be described later. For this reason, when the first shaft member and the second shaft member are displaced to move the substrate from the current position to the target position, the movable member, the substrate, or the like may be greatly displaced to cause interference with surrounding components. Therefore, when the difference between the displacement amounts of the first shaft member and the second shaft member when moving directly from the current position to the target position exceeds the first value, it moves to the target position via an intermediate position different from the target position. As described above, the displacement of the first shaft member and the second shaft member may be executed in multiple stages. By doing so, the above problem can be solved. In particular, when the rotation amount of the substrate relative to the vertical axis at the current position is other than the second value, the position in the horizontal plane is substantially the same as the current position, and the position where the rotation amount with respect to the vertical axis becomes the second value is intermediate. It is good also as a position. In this case, it is preferable to set the rotation amount of the mask with respect to the vertical axis to the second value.

  As described above, according to the present invention, since the relative position of the substrate with respect to the mask is adjusted by one drive unit, the apparatus is lower than the conventional apparatus in which a plurality of drive units are stacked in the vertical direction. The size of the apparatus can be reduced.

1 is a perspective view showing an embodiment of a printing apparatus according to the present invention. It is a top view which shows schematic structure of the printing apparatus in the state which has not installed the mask. It is a side view which shows schematic structure of the printing apparatus in the state which installed the mask. FIG. 2 is a block diagram illustrating a main electrical configuration of the printing apparatus. It is a figure which shows the structure of a board | substrate conveyance mechanism. It is a perspective view which shows the relationship between a movable plate and a drive unit. It is a top view which shows typically the relationship between a movable plate and a drive unit. It is an AA arrow directional view of FIG. It is a perspective view which shows a backup unit. It is a figure which shows the structure of the backup unit of FIG. It is a figure which shows the relationship between the coordinate system of an apparatus, and a virtual coordinate system. It is a figure which shows typically the relationship between an initial position and a target position. It is a flowchart which shows operation | movement of 2nd Embodiment of the printing apparatus concerning this invention.

  FIG. 1 is a perspective view showing an embodiment of a printing apparatus according to the present invention. In the figure, a state in which the main body cover is removed is shown in order to clearly show the internal configuration of the apparatus. FIG. 2 is a plan view showing a schematic configuration of the printing apparatus in a state where no mask is installed, and FIG. 3 is a side view showing a schematic configuration of the printing apparatus in a state where a mask is installed. FIG. 4 is a block diagram showing the main electrical configuration of the printing apparatus. In this printing apparatus, the substrate transport mechanism 20 is movable on the base 10 in the front-rear direction (Y-axis direction) of the apparatus. Moreover, on the base 10, the carry-in conveyors 31 and 31 are provided in the right side part of the apparatus, and the carry-out conveyors 32 and 32 are provided in the left side part of the apparatus.

  The carry-in conveyor 31 is provided to carry the unprocessed substrate 1 on which the solder paste is to be printed while conveying it in the X-axis direction. Then, when the carry-in conveyors 31 and 31 are driven in a state where the substrate carrying mechanism 20 is positioned between the carry-in conveyors 31 and 31 and the carry-out conveyors 32 and 32, the substrate 1 before the printing process is the “substrate carrying unit” of the present invention. Are fed to a pair of conveyors 251a and 251b provided in the substrate transport mechanism 20 corresponding to the above. The configuration and operation of the substrate transport mechanism 20 will be described in detail later.

  As will be described later, the substrate 1 is supported by the substrate clamp unit 26 from the side surface side and supported by the backup unit 27 from the lower surface side, thereby being firmly supported by the substrate transport mechanism 20. The substrate transport mechanism 20 is driven by the substrate transport mechanism control unit 43 of the control unit 40 and positioned with respect to the mask 51. This mask 51 has a thin plate-like stencil attached to the lower surface side of a mask frame (mask frame) 52. The mask frame 52 is held by the mask clamp unit 50 above the substrate transport mechanism 20 and the mask 51 is fixedly arranged. Is done. Then, the solder paste supplied from the solder supply unit 60 onto the mask 51 is spread by the squeegee 71 of the squeegee unit 70. At this time, the solder paste is printed on the upper surface of the substrate 1 through the through hole provided in the mask 51.

  After this printing process, the substrate transport mechanism 20 is moved and positioned between the carry-in conveyors 31 and 31 and the carry-out conveyors 32 and 32 again. Then, the processed substrates 1 subjected to the printing process by the conveyors 251 a and 251 b of the substrate transport mechanism 20 being driven by the substrate transport mechanism control unit 43 are transported to the carry-out conveyors 32 and 32. Thereafter, when the carry-out conveyors 32 and 32 are driven, the printed substrate 1 is carried out from the printing apparatus.

  In this embodiment, a substrate camera 81 for imaging a fiducial mark or the like of the substrate 1 is attached so as to be movable in the X-axis direction along a beam 12 fixed to the base 10. In addition, the substrate transport mechanism 20 is provided with a mask camera 82 for capturing a fiducial mark (not shown) on the lower surface of the mask 51 and identifying the position and type of the mask 51 so as to be movable in the X-axis direction. ing.

  Further, a cleaner 90 is attached to the front side of the substrate transport mechanism 20 in the Y-axis direction, and the cleaner 90 moves in the Y-axis direction as the substrate transport mechanism 20 moves in the Y-axis direction. The cleaner 90 is a device that cleans and removes the solder paste and the like attached to the mask 51 by printing the solder paste on the substrate 1.

  In the printing apparatus configured as described above, a control unit 40 for controlling the entire printing apparatus is provided. The control unit 40 includes an arithmetic processing unit 41, a program storage unit 42, and a substrate transport mechanism control unit 43. The arithmetic processing unit 41 is constituted by a CPU or the like, and repeats the printing process by controlling each unit of the printing apparatus according to a printing program stored in advance in the program storage unit 42. Reference numeral 45 in the figure is a display / operation unit for displaying a printing program, a cleaning program, etc., and for an operator to input information such as various data and commands to the control unit 40. Reference numeral 46 denotes an input / output control unit.

  Next, the configuration and operation of the substrate transport mechanism 20 will be described in detail. FIG. 5 is a diagram showing the configuration of the substrate transport mechanism. FIG. 6 is a perspective view showing the relationship between the movable plate and the drive unit. FIG. 7 is a plan view schematically showing the relationship between the movable plate and the drive unit. The substrate transport mechanism 20 includes a movable plate 21 having a rectangular shape in plan view, a Y-axis drive unit 22 that drives the movable plate 21 in the Y-axis direction, and the movable plate 21 in a two-dimensional manner in a horizontal plane (XY plane). And an X / R axis drive unit 23 that rotates relative to the vertical axis, a Z axis drive unit 24 that moves the movable plate 21 up and down, a conveyor unit 25, a substrate clamp unit 26, and a backup unit 27. In this embodiment, the movable plate 21 corresponds to the “movable member” of the present invention, but the shape of the “movable member” is not limited to a plate shape or a rectangular shape.

  In the present embodiment, as shown in FIG. 7, two guide rails 232 a and 232 b are separated from the upper surface of the base 10 by a predetermined distance in the X-axis direction (first horizontal direction). Direction). The guide rail 232a is provided with two sliders 233a and 233b so as to be slidable in the Y-axis direction, while the guide rail 232b is also provided with two sliders 233c and 233d so as to be slidable in the Y-axis direction.

  Of these four sliders, on the slider 233a, a guide rail 234a extends in the X-axis direction and an X1-axis drive motor 235a is provided. A slider 236a is provided on the guide rail 234a so as to be slidable in the X-axis direction, and a shaft member 231a is erected upward from the slider 236a. For this reason, the shaft member 231a is movable two-dimensionally in a horizontal plane. In this embodiment, the X1 axis drive motor 235a is operated in response to a signal from the substrate transport mechanism control unit 43, so that the slider 236a moves in the X axis direction (first horizontal direction) via the ball screw 237a. Thus, the shaft member 231a is moved in the X-axis direction. The upper end side of the shaft member 231a penetrates the front left portion of the movable plate 21, and the front left portion of the movable plate 21 is slidably supported with respect to the intermediate portion of the shaft member 231a. Thus, in this embodiment, the shaft member 231a and the X1-axis drive motor 235a correspond to the “first shaft member” and the “first shaft drive unit” of the present invention, respectively. In the following, the direction in which the shaft member 231a is moved by the X1-axis motor 235a in this way is referred to as “X1-axis direction”.

  In addition, on the slider 233b, the pivot arm 239b is pivotally supported by the support shaft 238b so as to be rotatable with respect to the slider 233b, and a shaft member 231b is provided upright from the pivot arm 239b. For this reason, the shaft member 231b is movable two-dimensionally in a horizontal plane. The upper end side of the shaft member 231b penetrates the rear left portion of the movable plate 21, and the rear left portion of the movable plate 21 is slidably supported with respect to the intermediate portion of the shaft member 231b.

  Further, the slider 233c is configured in the same manner as the slider 233b. That is, the pivot arm 239c is pivotally supported with respect to the slider 233c by the support shaft 238c, and the shaft member 231c is erected above the pivot arm 239c. For this reason, the shaft member 231c is movable two-dimensionally in a horizontal plane. The upper end side of the shaft member 231c penetrates the front right portion of the movable plate 21, and the front right portion of the movable plate 21 is slidably supported with respect to the intermediate portion of the shaft member 231c.

  The slider 233d is configured in the same manner as the slider 233a. That is, on the slider 233d, a guide rail 234d extends in the X-axis direction and an X2-axis drive motor 235d is provided. A slider 236d is provided on the guide rail 234d so as to be slidable in the X-axis direction, and a shaft member 231d is provided above the slider 236d. For this reason, the shaft member 231d is movable two-dimensionally in a horizontal plane. In this embodiment, the X2 axis drive motor 235d is operated in response to a signal from the substrate transport mechanism control unit 43 to move the slider 236d in the X axis direction (first horizontal direction) via the ball screw 237d. Thus, the shaft member 231d is moved in the X-axis direction. The upper end side of the shaft member 231d penetrates the rear right portion of the movable plate 21, and the rear right portion of the movable plate 21 is slidably supported with respect to the intermediate portion of the shaft member 231d. Thus, in this embodiment, the shaft member 231d and the X2-axis drive motor 235d correspond to the “second shaft member” and the “second shaft drive unit” of the present invention, respectively. In the following, the direction in which the shaft member 231d is moved by the X2-axis motor 235d in this way is referred to as the “X2-axis direction”.

  Between the sliders 233a and 233b, a slider 233e1 is slidable in the Y-axis direction along the guide rail 232a, and between the sliders 233c and 233d, the slider 233e2 is slidable in the Y-axis direction along the guide rail 232b. Further, both end portions of the plate 233e3 are mounted on the sliders 233e1 and 233e2, respectively, so as to bridge the sliders 233e1 and 233e2. For this reason, the sliders 233e1 and 233e2 and the plate 233e3 are integrally movable in the Y-axis direction. Further, two guide rails 234e and 234e are provided on the plate 233e3 so as to be separated from each other by a predetermined distance in the Y-axis direction. A slider 236e is provided on these guide rails 234e so as to be slidable in the X-axis direction, and a shaft member 231e is erected above the slider 236e. For this reason, the shaft member 231e is movable two-dimensionally in a horizontal plane. The upper end side of the shaft member 231e passes through the central portion of the movable plate 21, and the central portion of the movable plate 21 is slidably supported with respect to the intermediate portion of the shaft member 231e. Thus, in this embodiment, the shaft member 231e is located on the diagonal line connecting the front left part and the rear right part of the movable plate 21, and the shaft members 231a and 231d are arranged so as to sandwich the shaft member 231e. This shaft member 231e corresponds to the “third shaft member” of the present invention.

  As described above, the movable plate 21 is pivotally supported by the five shaft members 231a to 231e so as to be movable in the horizontal plane (XY plane) and rotatable with respect to the vertical axis. Of these shaft members, the shaft members 231a and 231d are moved in the X1 axis direction and the X2 axis direction by the X1 axis drive motor 235a and the X2 axis drive motor 235d, respectively. The movable plate 21 moves in the horizontal plane or rotates with respect to the vertical axis in accordance with the amount of movement of the shaft member 231d in the X2 axis direction. Thus, in this embodiment, the X / R axis drive unit 23 having the shaft members 231a to 231e, the X1 axis drive motor 235a, and the X2 axis drive motor 235d functions as the “first drive unit” of the present invention.

  Of the five shaft members that pivotally support the movable plate 21, the shaft member 231e is movable in the Y-axis direction integrally with the slider 236e, the guide rail 234e, the sliders 233e1, 233e2, and the plate 233e3. The Y-axis drive motor 221 is actuated in response to a signal from the transport mechanism control unit 43 and is moved in the Y-axis direction (second horizontal direction) via the ball screw 222. Therefore, the movable plate 21 and the X / R axis drive unit 23 are integrally moved in the Y axis direction by the operation of the Y axis drive motor 221. Thus, the Y-axis drive unit 22 having the Y-axis drive motor 221 and the ball screw 222 functions as the “second drive unit” of the present invention. In this embodiment, the movement amount of the movable plate 21 and the X / R axis drive unit 23 by the Y axis drive unit 22 is set larger than the movement amount of the movable plate 21 by the X / R axis drive unit 23. The movable plate 21 and the X / R axis drive unit 23 can be moved integrally to the front side and the rear side of the apparatus.

  The movable plate 21 is provided with a Z-axis drive unit 24. In the Z-axis drive unit 24, as shown in FIG. 5, a beam member 241b is attached to the upper end portion of the shaft members 231c and 231d so as to bridge the shaft members 231c and 231d on the right side surface side. Also, two ball screw shafts 242c and 242d are extended downward from the lower surface of the beam member 241b. That is, the upper ends of these ball screw shafts 242 c and 242 d are fixed to the beam member 241 b, while the lower ends extend through the movable plate 21 to the vicinity of the slider group of the X / R axis drive unit 23. Further, intermediate portions of the ball screw shafts 242 c and 242 d are respectively screwed into ball screw brackets 243 c and 243 d fixed to the movable plate 21 and connected to the movable plate 21. In addition, pulleys 244c and 244d are fixed to the lower surface side of the ball screw brackets 243c and 243d, and the rotational driving force from the Z-axis drive motor 245 can be transmitted to the ball screw brackets 243c and 243d. The left side is also configured in the same manner as the above right side. That is, the upper ends of the ball screw shafts 242a and 242b are fixed to the lower surface of the beam member 241a attached so as to connect the upper ends of the shaft members 231a and 231b, while the lower ends of the ball screw shafts 242a and 242b. Extends vertically through the movable plate 21 to the vicinity of the slider group of the X / R axis drive unit 23. Further, intermediate portions of the ball screw shafts 242a and 242b are connected to the movable plate 21 via ball screw brackets 243a and 243b, respectively. The rotational driving force from the Z-axis drive motor 245 is transmitted to the ball screw brackets 243a and 243b by pulleys 244a and 244b fixed to the lower surface side of the ball screw brackets 243a and 243b.

  FIG. 8 is a view taken in the direction of arrows AA in FIG. 5 and is a plan view showing a mechanism for transmitting a rotational driving force generated by the Z-axis drive motor 245. In the figure, reference numerals 244e to 244h denote pulleys that are rotatably attached to the lower surface of the movable plate 21. The belt 246 is stretched around the rotation shafts of the pulley 244e and the Z-axis drive motor 245, and the belt 247 is stretched around all the pulleys 244a to 244h. The rotational drive force generated by the Z-axis drive motor 245 is applied to the ball. Transmission to the screw brackets 243a to 243d is possible. For this reason, when the Z-axis drive motor 245 is rotated in a predetermined direction by the substrate transport mechanism control unit 43, all the ball screw brackets 243a to 243d are simultaneously rotated in the same direction, and the movable plate 21 is raised accordingly. Conversely, when the Z-axis drive motor 245 is rotated in the reverse direction, the rotation direction of all the ball screw brackets 243a to 243d is reversed and the movable plate 21 is lowered. Thus, in the present embodiment, the Z-axis drive unit 24 corresponds to the “third drive unit” of the present invention. The beam members 241a and 241b and the Z-axis drive motor 245 correspond to the “shaft support member” and the “lifting drive unit” of the present invention, respectively.

  A conveyor unit 25 is provided on the movable plate 21. In this conveyor unit 25, a pair of conveyors 251a and 251b are extended along the X-axis direction. These conveyors 251a and 251b are arranged while being spaced apart from each other by a predetermined distance in the Y-axis direction. The front conveyor 251a is supported by a support member 252a attached to the movable plate 21, while the rear conveyor 251b is movable. It is supported by a support member 252b attached to the plate 21. And in the state which adjusted the height position of the movable plate 21 with the above-mentioned Z-axis drive unit 24, and positioned the pair of conveyors 251a, 251b at the same height as the carry-in conveyors 31, 31 and the carry-out conveyors 32, 32, When the carry-in conveyors 31 and 31 are driven and the board carrying mechanism drive motor 251 is driven by the board carrying mechanism control unit 43, the conveyors 251a and 251b receive the unprocessed substrates 1 sent from the carry-in conveyors 31 and 31. . In addition, when the carry-out conveyors 32 and 32 are driven in this state, and the substrate carrying mechanism drive motor 251 is driven by the substrate carrying mechanism control unit 43, the processed substrate 1 subjected to the printing process as described above is transferred to the conveyor. 251a and 251b are conveyed to the carry-out conveyors 32 and 32.

  In addition, clamp pieces 261 and 261 constituting the substrate clamp unit 26 are attached to the support members 252a and 252b. Then, the substrate clamp switching valve 262 is controlled by the substrate transport mechanism control unit 43, whereby the clamp pieces 261 and 261 are driven by an actuator such as a cylinder to support the substrate 1 on the conveyors 251a and 251b from the side. Moreover, the side support of the board | substrate 1 by the clamp pieces 261 and 261 is cancelled | released by driving this actuator to a reverse direction.

  Thus, the backup unit 27 is positioned on the movable plate 21 so as to be positioned between the support member 252a supporting the conveyor 251a and the clamp piece 261 and the support member 252b supporting the conveyor 251b and the clamp piece 261. Is arranged. Hereinafter, the configuration of the backup unit 27 will be described with reference to FIGS. 9 and 10.

  FIG. 9 is a perspective view showing the backup unit. FIG. 10 is a diagram showing the configuration of the backup unit of FIG. The backup unit 27 employed in this embodiment includes a backup plate 271, a plurality of backup pins 272, an elevator mechanism 273 that is disposed between the backup plate 271 and the movable plate 21 and drives the backup plate 271 to move up and down, An urging portion 274 a made of, for example, a compression coil spring that urges an upward force against the plate 271, and a guide bar 274 b provided so as to penetrate the hollow central portion of the urging portion 274 a and the movable plate 21. ing. The backup pin 272 is erected upward from the backup plate 271, and the lower surface of the substrate 1 can be supported from below by the tip of the backup pin 272. In FIG. 9, the backup pin 272 is not shown.

  The elevating mechanism unit 273 has a parallel link mechanism 275 having one connected to the movable plate 21 and the other connected to the backup plate 271. The parallel link mechanism 275 is connected to a ball screw shaft 277 that rotates by receiving the rotational driving force of the lifting drive motor 276. As described above, while the substrate 1 is being transported by the conveyors 251a and 251b, the backup plate 271 and the backup pin 272 are retracted to a position lower than the substrate transport surface. Then, the slider on the lower side of the parallel link mechanism 275 moves in the rear direction along the guide rail fixed on the movable plate 21 by rotating the lifting drive motor 276 in a predetermined direction by the substrate transport mechanism control unit 43. The backup plate 271 is moved upward according to the movement. In this embodiment, the substrate transport mechanism controller 43 rotates the lifting drive motor 276 in a predetermined direction so that the tip of the backup pin 272 contacts the substrate 1 on the conveyors 251a and 251b, and further from the conveyors 251a and 251b. The backup plate 271 and the backup pin 272 are raised to a height that is flush with the upper surfaces of the clamp pieces 261 and 261. Thereby, the backup pin 272 supports the lower surface of the substrate 1 from below (backup). At this time, since the urging force by the urging portion 274a is applied to the backup plate 271 in addition to the force obtained by converting the rotational driving force of the elevating drive motor 276 by the parallel link mechanism 275, the conventional device Thus, the lift drive motor 276 can be reduced in size compared to the case where the substrate is backed up only by the drive motor.

  In this embodiment, the guide bar 274b is suspended downward from the lower surface of the backup plate 271, and the lower end of the guide bar 274b penetrates the hollow central portion of the compression coil spring constituting the biasing portion 274a and the movable plate 21. Is provided. The lower end of the guide bar 274b is pivotally supported with respect to the movable plate 21 by a support member such as a slide bearing. For this reason, the expansion and contraction of the compression coil spring 274a and the vertical movement of the movable plate 21 are performed along the guide bar 274b. Therefore, when the up-and-down drive motor 276 is operated to raise and lower the backup plate 271 and the backup pin 272 relative to the movable 21, the movement of the backup plate 271 and the backup pin 272 is allowed only in the Z-axis direction. As a result, in the present embodiment, the substrate 1 can be moved up and down in the Z-axis direction without being translated in the X-axis direction or the Y-axis direction.

  On the other hand, in order to cancel the backup of the substrate, the substrate transport mechanism control unit 43 reversely rotates the elevation drive motor 276, and the reverse plate moves the backup plate 271 to the movable plate 21 side to transfer the substrate 1 to the conveyor 251a. , 251b, the backup pin 272 moves downward from the lower surface of the substrate 1.

  Next, an operation performed after the unprocessed substrate 1 is carried into the conveyors 251a and 251b of the substrate transport mechanism 20 in the printing apparatus configured as described above will be described. In addition, when the board | substrate 1 is carried in in this way, the board | substrate conveyance mechanism 20 is located between the carrying-in conveyors 31 and 31 and the carrying-out conveyors 32 and 32, ie, the center part of the base 10 upper surface. Further, the clamp pieces 261 and 261 are not held. Further, the backup unit 27 lowers the backup plate 271 toward the movable plate 21 and the backup pins 272 are retracted below the substrate 1.

  When it is confirmed that the substrate 1 is carried into the conveyors 251a and 251b, the arithmetic processing unit 41 executes the following processing in accordance with a printing program stored in advance in the program storage unit 42. First, the backup plate 271 is moved upward by the lift drive motor 276 to transfer the substrate 1 from the conveyors 251a and 251b to the tip of the backup pin 272, and the upper surface of the substrate 1 is flush with the upper surfaces of the clamp pieces 261 and 261. The substrate 1 is raised to a certain height. Subsequently, the clamp holding of the substrate 1 by the clamp pieces 261 and 261 is executed. Thus, in this embodiment, the substrate 1 is supported by the backup unit 27 from the lower side and supported by the substrate clamp unit 26 from the side, and the substrate 1 is held in a state where the substrate 1 is separated from the conveyors 251a and 251b. Thus, the substrate clamp unit 26 and the backup unit 27 function as the “substrate support unit” of the present invention.

  Next, if it is necessary to clean the lower surface of the mask 51, cleaning by the cleaner 90 is performed. When it is necessary to image the fiducial mark on the lower surface of the mask 51, the substrate transport mechanism 20 is moved in the Y-axis direction and the mask camera 82 is moved in the X-axis direction. The fiducial marks are sequentially imaged. Subsequently, the substrate transport mechanism 20 is moved in the Y-axis direction, and the substrate camera 81 sequentially images the fiducial marks on the substrate 1.

  In this way, the position information of the fiducial mark on the mask 51 and the substrate 1 is acquired, and the fiducial mark on the lower surface of the mask 51 and the fiducial mark on the substrate 1 are matched based on the position information. The X1 axis drive motor 235a and the X2 axis drive motor 235d of the X / R axis drive unit 23 of the substrate transport mechanism 20 are driven and controlled to position the substrate 1 with respect to the mask 51. This drive control will be described in detail later.

  At the same time as the positioning of the substrate 1 with respect to the mask 51 is started, the movable plate 21 is raised by the Z-axis drive unit 24 and the substrate 1 is started to rise toward the printing position. In the completed state, the substrate 1 is brought into close contact with the lower surface of the mask 51. Thereafter, paste such as cream solder is supplied to the upper surface of the mask 51, and the squeegee 71 is moved to one side in the Y-axis direction while controlling the printing load and moving speed. Thereby, the paste is printed at a predetermined position on the upper surface of the substrate 1 through the supply hole of the mask 51.

  Thereafter, the movable plate 21 is lowered by the Z-axis drive unit 24 and the X / R-axis drive unit 23 is driven by the amount moved for positioning the substrate 1 with respect to the mask 51 to return to the original position (initial position). Return to. Then, the substrate transport mechanism 20 is moved between the carry-in conveyors 31 and 31 and the carry-out conveyors 32 and 32 by driving and controlling the Y-axis drive unit 22, and then the holding of the substrate 1 by the clamp pieces 261 and 261 is released. Subsequently, the backup plate 271 is lowered, the substrate 1 is transferred from the backup pins 272 to the conveyors 261a and 261b, and the backup pins 272 are retracted below the substrate 1. Then, the printed substrate 1 is carried out to the carry-out conveyors 32 and 32.

  Next, the substrate positioning control executed in this embodiment will be described with reference to FIGS. In the present embodiment, as described above, the substrate transport mechanism control unit 43 drives and controls the X1 axis drive motor 235a and the X2 axis drive motor 235d of the X / R axis drive unit 23, and moves the shaft member 231a in the X1 axis direction (guide rail). And the shaft member 231d is moved in the X2 axis direction (extension direction of the guide rail 234d). Accordingly, the movable plate 21 is moved in the horizontal plane (XY plane) or rotated with respect to the vertical axis to position the substrate 1 with respect to the mask 51. Therefore, it is preferable to perform full control using control amounts related to the X1 axis and the X2 axis on the apparatus side. However, it is easy for an operator or the like to control by the amount of movement in the X-axis direction and the amount of movement in the R-axis direction (rotation amount about the vertical axis) as in the conventional apparatus, and prevents setting errors and the like. It is suitable for. Therefore, in this embodiment, it is assumed that a virtual X axis and a virtual R axis exist, and the positioning of the substrate 1 is controlled on the virtual X axis and the virtual R axis on the upper layer side of the substrate transport mechanism control unit 43, and the control is performed. The information, that is, the movement amount in the X-axis direction and the movement amount in the R-axis direction is given to the substrate transport mechanism control unit 43, while the substrate transport mechanism control unit 43 converts the control information into the movement amounts on the X1 axis and the X2 axis. Then, a control command related to the movement amount is given to the X1-axis drive motor 235a and the X2-axis drive motor 235d to perform desired positioning control.

  FIG. 11 is a diagram showing the relationship between the coordinate system of the apparatus and the virtual coordinate system. FIG. 11A shows the origin return state, while FIG. 11B shows the initial position. The CX axis in the figure is an axis parallel to the conveyance direction of the substrate 1 by the carry-in conveyors 31 and 31 and the carry-out conveyors 32 and 32, and basically coincides with the X axis of the printing apparatus. Further, “force point 1” in the figure means a rotation center in which the front left portion of the movable plate 21 and the shaft member 231a are connected so as to be relatively rotatable, that is, an axis of the shaft member 231a. “2” means a rotation center in which the rear right portion of the movable plate 21 and the shaft member 231d are connected so as to be relatively rotatable, that is, an axis of the shaft member 231d.

When each part of the printing apparatus returns to the origin return position, the conveyors 251a and 251b and the movable plate 21 of the substrate transport mechanism 20 may be inclined with respect to the CX axis as shown in FIG. There is. For this reason, in order to carry in the board | substrate 1 in the board | substrate conveyance mechanism 20, or to carry out from the board | substrate conveyance mechanism 20, it is necessary to move to the initial position shown in the same figure (b). Here, the “initial position” means that the conveyors 251a and 251b of the substrate transport mechanism 20 are parallel to the CX axis, and the clearances between the conveyors 31 and 31 and the conveyors 32 and 32 and the conveyors 251a and 251b are equal. It is a position. In this specification, the coordinates X1 on the X1 axis and the coordinates X2 on the X2 axis at the initial position are X1i and X2i, respectively, and the virtual coordinates (virtual X-axis, virtual (R axis) is (0, 0). Further, the coordinates of force point 1 and force point 2 from the machine origin in the initial position are set to force point 1 (CX, Y) and force point 2 (CX, Y), respectively, and force point 1 (CX, Y) = (Ix1, Iy1) )
Force point 2 (CX, Y) = (Ix2, Iy2)
And

  Here, in the case where the movable plate 21 is moved from the initial position (0, 0) to the target position (Xt, Rt), the coordinates (X, R) in the virtual coordinate system based on FIG. Consideration is divided into conversion to X1, X2) and conversion from coordinates (X1, X2) to coordinates (X, R).

FIG. 12 is a diagram schematically showing the relationship between the initial position and the target position. In this case, the force point 1 (Tx1, Ty1) is a primary transformation (affine transformation) and is given by the following equation.

Further, the force point 2 (Tx2, Ty2) is a linear transformation (affine transformation) and is given by the following equation.

Therefore, the coordinate X1 on the X1 axis and the coordinate X2 on the X2 axis when moving to the target position are respectively

It can ask for.

Next, a case will be described in which the position (Xc, Rc) in the virtual coordinate system is obtained from the current coordinates X1c on the X1 axis, the current coordinates X2c on the X2 axis, and the initial positions Ix1, Ix2. An average Xc of the movement amounts from the initial position of the coordinate X1 on the X1 axis and the coordinate X2 on the X2 axis is the movement amount in the X-axis direction. Therefore, the current coordinate Xc in the virtual coordinate system can be obtained by the following equation.

On the other hand, the current position Rc in the virtual coordinate system can be obtained as follows. That is, as shown in FIG. 12 (b), when considering a right triangle whose hypotenuse is a straight line connecting two force points 1 and 2, the distance L between force point 1 and force point 2 is fixed to a value set by the device design. Therefore, even if the movable plate 21 moves / rotates, it does not change and can be calculated from machine data (design data).

Here, the length Lxi of the base of the right triangle when in the initial position can be obtained from the distance in the X-axis direction between the two power points of the machine data. That means
Lxi = | Ix1-Ix2 |
It can ask for.

The length Lxc of the base of the right triangle in the moving state is as follows from the amount of movement from the initial position of the X1 axis and the X2 axis.

From these values, the angle formed by the base and hypotenuse of each right triangle is determined, and the difference is the current position Rc of the virtual R axis. Therefore, the following formula

Thus, the current position Rc can be obtained.

  As described above, according to the present embodiment, the five shaft members 231a to 231e are provided movably in the horizontal plane (XY plane), and the movable plate 21 is pivotally supported by these shaft members 231a to 231e. Yes. For this reason, the movable plate 21 is movable in a horizontal plane and is rotatable with respect to the vertical axis. The shaft member 231a is driven in the X1 axis direction (extension direction of the guide rail 234a), and the shaft member 231d is driven in the X2 axis direction (extension direction of the guide rail 234d), thereby moving the movable plate 21 in the horizontal plane ( The substrate 1 can be positioned with respect to the mask 51 by moving within the (XY plane) or rotating with respect to the vertical axis. As described above, in this embodiment, the relative position of the substrate 1 with respect to the mask 51 is adjusted by the X / R axis drive unit 23, and the apparatus is made lower than the conventional apparatus in which a plurality of drive units are stacked in the vertical direction. Therefore, the apparatus can be downsized.

  Further, according to this embodiment, the plurality of shaft members 231a to 231e are pivotally supported, and the self-weight of the movable plate 21 and the load applied to the movable plate 21 are dispersed around the plurality of shaft members 231a to 231e. To position the substrate 1. For this reason, rotational positioning can be stably performed with high accuracy.

  Further, the movable plate 21 is configured to be moved between the lower position of the mask 51 and the lower position of the substrate camera 81 by the Y-axis drive unit 22, and the substrate transport mechanism 20 can be moved greatly in the Y-axis direction. In addition, various operations such as loading / unloading of the substrate and imaging of the upper surface of the substrate can be performed at a position away from the mask 51. Therefore, workability and design freedom can be improved.

  Ball screw shafts 242a to 242d constituting the Z-axis drive unit 24 are suspended from the upper ends of the shaft members 231a to 231d, and the lower ends thereof extend to the vicinity of the slider group of the X / R-axis drive unit 23. . The movable plate 21 is driven up and down along these ball screw shafts 242a to 242d. Therefore, as compared with the case where the Z-axis drive units are simply stacked as in the conventional device, it is possible to effectively prevent the device from being enlarged in the vertical direction.

  By the way, when the shaft members 231a and 231d are moved in the X1 axis direction and the X2 axis direction by the X1 axis drive motor 235a and the X2 axis drive motor 235d, respectively, the movable plate 21 supported by the shaft members 231a to 231e is simple. Instead of moving in the X-axis direction, as described above, a two-dimensional movement operation in the horizontal plane (XY plane) and a rotation operation around the vertical axis are involved. For this reason, when the shaft member 231a or the shaft member 231d is displaced to move the substrate 1 from the current position to the target position, the movable plate 21, the substrate 1 or the like may be greatly displaced to cause interference with surrounding components. . Therefore, in the second embodiment described below, when the displacement amount of the shaft member when moving directly from the current position to the target position exceeds a predetermined value, the substrate 1 passes through an intermediate position different from the target position. The displacement of the first shaft member and the second shaft member is executed in multiple stages so as to move to the center. Hereinafter, a description will be given with reference to FIG.

  FIG. 13 is a flowchart showing the operation of the second embodiment of the printing apparatus according to the present invention. In the second embodiment, the arithmetic processing unit 41 executes the following processing steps when moving the movable plate 21 to the target position in order to position the substrate 1. First, a coordinate X1t on the X1 axis and a coordinate X2t on the X2 axis are calculated from the target coordinates (Xt, Rt) of the target position (step S1). Also, the coordinates X1c on the X1 axis and the coordinates X2c on the X2 axis of the current position are acquired (step S2). These derivation methods are as described above.

  Next, the allowable maximum displacement amount Dmax of the X1 axis and the X2 axis is read from the machine data stored in the storage means such as the program storage unit 42 (step S3). The maximum displacement amount Dmax is a displacement amount by which the shaft members 231a and 231d can be moved along the X1 axis and the X2 axis while satisfying the condition that the substrate transport mechanism 20 and the substrate 1 do not interfere with surrounding components. Means the maximum difference value. That is, when the difference between the movement amount along the X1 axis and the movement amount along the X2 axis is smaller than the maximum displacement amount Dmax, the rotation amount of the movable plate 21 is relatively small. Under such circumstances, the shaft members 231a and 231d As long as the position is displaced, the interference does not occur, and the substrate 1 can be positioned satisfactorily.

In the next step S4, the displacement amount DA between the X1 and X2 axes when only the shaft member 231a is moved to the target position X1t along the X1 axis is obtained. In other words, the following formula DA = | X1t−X2c |
Based on the above, the displacement amount DA is calculated. In step S5, the displacement DB between the X1 and X2 axes when only the shaft member 231d is moved to the target position X2t along the X2 axis is obtained. In other words, the following formula DB = | X2t−X1c |
The displacement amount DB is calculated based on the above. When it is determined that the displacement amounts DA and DB calculated in this way are both smaller than the maximum displacement amount Dmax (when both “YES” are determined in steps S6 and S7), the shaft member 231a moves to the X1 axis. And the shaft member 231b is moved to the target position X2t along the X2 axis, and the movable plate 21 is moved to the target position (Xt, Rt) (step S8). Thereby, the positioning of the substrate 1 with respect to the mask 51 is completed.

  On the other hand, if at least one of the displacement amounts DA and DB is greater than or equal to the maximum displacement amount Dmax, the current position is not moved directly to the target position, but is moved to the intermediate position, and then the process returns to step S2 and the series of processes described above. I do. In this embodiment, the current R-axis coordinate of the movable plate 21 is zero. For example, as shown in FIG. 11B, the conveyors 251 a and 251 b of the substrate transport mechanism 20 are the carry-in conveyors 31 and 31 and the carry-out conveyors 32 and 32. The processing is different between the case where it is confirmed that the relation is parallel to the case and the case where it is confirmed that the R-axis coordinate is not zero and the parallel relation of the conveyor is not ensured, for example, as shown in FIG. It is That is, in the latter case (in the case of “NO” in step S9), the shaft member 231a, 231d is X1 so that the coordinate Rc in the R-axis direction becomes zero while maintaining the coordinate Xc in the X-axis direction of the movable plate 21 as it is. The conveyors 251a and 251b of the substrate transport mechanism 20 are positioned in parallel with the carry-in conveyors 31 and 31 and the carry-out conveyors 32 and 32, respectively, along the axis and the X2 axis (step S10). In this way, in the operation of rotating the movable plate 21 around the vertical axis without moving in the X-axis direction and adjusting the R-axis coordinate Rc to zero, the difference value of the displacement amounts of the shaft members 231a and 231d is small. The maximum displacement Dmax is not exceeded. After positioning to the intermediate position in this way, the process returns to step S2.

If “YES” is determined in step S9, that is, if the conveyors 251a and 251b of the substrate transport mechanism 20 are in parallel with the carry-in conveyors 31 and 31 and the carry-out conveyors 32 and 32, step S11 is performed. To S15 are executed. That is, in step S11, the difference M1 between the current position X1c of the shaft member 231a on the X1 axis and the target position X1t is obtained. That is, the following equation M1 = | X1t−X1c |
Based on the above, the difference M1 is calculated. In step S12, a difference M2 between the current position X2c of the shaft member 231d on the X2 axis and the target position X2t is obtained. That is, the following equation M2 = | X2t−X2c |
Based on the above, the difference M2 is calculated. When it is determined in step S13 that both the differences M1 and M2 exceed the maximum displacement amount Dmax, the shaft members 231a and 231d are both moved in the desired direction by the maximum displacement amount Dmax (step S14). On the other hand, when it is determined in step S13 that at least one of the differences M1 and M2 is equal to or less than the maximum displacement Dmax, the shaft members 231a and 231d are both moved in the desired direction by the movement amount having the smaller difference (step S15). ). After positioning to the intermediate position in this way, the process returns to step S2.

  As described above, according to the second embodiment of the present invention, when the movable plate 21 is directly moved from the current position (Xc, Rc) to the target position (Xt, Rt) in order to position the substrate 1, the shaft member When the difference between the displacement amounts of 231a and 231d exceeds the maximum displacement amount Dmax, the movable plate 21 is moved and rotated while keeping the difference between the displacement amounts of the shaft members 231a and 231d not exceeding the maximum displacement amount Dmax. After positioning to an intermediate position different from (Xt, Rt), it is moved to the target position. As described above, since the displacement of the shaft members 231a and 231d is executed in multiple stages so that the difference between the displacement amounts of the shaft members 231a and 231d is always equal to or less than the maximum displacement amount Dmax, the movable plate 21 is being positioned. In addition, it is possible to reliably prevent the movable plate 21 and the substrate 1 from interfering with surrounding components.

  In the second embodiment described above, the “maximum displacement amount Dmax” corresponds to the “first value” of the present invention, and the rotation amount “zero” with respect to the vertical axis corresponds to the “second value” of the present invention. However, these “first value” and “second value” are not limited to the above-described values, and components (for example, the carry-in conveyor 31 and the carry-out conveyor) disposed around the movable plate 21 and the substrate 1. “First value” and “second value” may be set on the basis of the arrangement relationship with each other.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, the movable plate 21 is pivotally supported by the five shaft members 231a to 231e, but the number of the shaft members is not limited to this, and the movable plate is composed of three or more shaft members. 21 may be pivotally supported.

  In the above embodiment, the rectangular movable plate 21 is used as the “movable member” of the present invention, but the shape of the movable plate 21 is not limited to this and is arbitrary.

  Furthermore, in the above-described embodiment, the shaft support structure using the rotating arms 239b and 239c is employed as described above in order to configure the shaft members 231b and 231c so as to be two-dimensionally movable. However, the present invention is not limited to this. For example, a slider that is slidable in the X-axis direction may be provided in the same manner as other shaft members, and the shaft member may be erected on the slider.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 20 ... Board | substrate conveyance mechanism 21 ... Movable plate (movable member)
22 ... Y-axis drive unit (second drive unit)
23 ... X / R axis drive unit (first drive unit)
24 ... Z-axis drive unit (third drive unit)
26 ... Substrate clamp unit (Substrate support unit)
27 ... Backup unit (substrate support unit)
40. Control unit (control means)
41. Arithmetic processing part (control means)
231a ... (first) shaft member 231d ... (second) shaft member 235a ... X1-axis drive motor (first shaft drive unit)
235d ... X2 axis drive motor (second axis drive unit)
241a, 241b ... Beam members (shaft support members)
245 ... Z-axis drive motor (lifting drive unit)
Dmax: Maximum displacement

Claims (5)

In a printing apparatus for positioning a substrate with respect to a mask held in a horizontal state by a substrate transport unit and superimposing the substrate on a lower surface of the mask and printing a paste on an upper surface of the substrate through a through-hole formed in the mask ,
The substrate transfer means includes a substrate support unit that holds a substrate, a movable member that is movable in a horizontal plane while holding the substrate support unit and is rotatable with respect to a vertical axis, and the movable member that is in a horizontal plane. A first drive unit that moves in a two-dimensional manner and rotates relative to the vertical axis to adjust the relative position of the substrate with respect to the mask,
The first drive unit includes:
Three or more shaft members that are movable two-dimensionally in a horizontal plane while pivotally supporting the movable member;
A first shaft drive unit that drives a first shaft member of the shaft members in a first horizontal direction;
A printing apparatus comprising: a second shaft driving unit that drives a second shaft member of the shaft members in a first horizontal direction. The substrate transport means further includes a second drive unit that moves the movable member in a second horizontal direction,
The printing apparatus according to claim 1, wherein the second drive unit moves the movable member between a lower position of the mask and a position away from the lower position. The movable member is slidably supported with respect to an intermediate portion of the shaft member extending in the vertical direction, and is movable up and down in the vertical direction.
The substrate transport means further includes a third drive unit that moves the movable member in the vertical direction,
The third drive unit includes a shaft support member attached to an upper end portion of the shaft member, and an elevating drive unit that moves the movable member along the shaft member below the shaft support member. Item 3. The printing apparatus according to Item 1 or 2. Control means for controlling the first axis driving unit and the second axis driving unit to displace the first axis member and the second axis member to move the substrate from a current position to a target position,
The control means is configured such that the substrate differs from the target position when a difference in displacement amount between the first shaft member and the second shaft member when moving directly from the current position to the target position exceeds a first value. The printing according to any one of claims 1 to 3, wherein the displacement of the first shaft member and the second shaft member is performed in multiple stages so as to move to the target position via an intermediate position. apparatus.   The control means is configured such that a difference in displacement amount between the first shaft member and the second shaft member when moving directly from the current position to the target position exceeds the first value, and the substrate at the current position When the rotation amount with respect to the vertical axis is other than the second value, the position in the horizontal plane is substantially the same as the current position, and the position where the rotation amount with respect to the vertical axis becomes the second value is the intermediate position. The printing apparatus according to claim 4.

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