Component mounting machine and production system

Abstract

A component mounting machine comprising a holding device that holds a substrate, and a mounting head that mounts a component on the substrate held by the holding device, wherein the height of a component mounted on the substrate is detected, and the substrate is lowered when it is determined that the component and the mounting head interfere with each other on the basis of a detected component height that is the detected height of the component.

Description

Component placement machines and production systems

[0001] The present disclosure relates to a component mounting machine that mounts components on a board, and a production system that includes a plurality of component mounting machines.

[0002] The following patent document describes a component mounting machine that mounts components on a board.

[0003] Japanese Patent Application Laid-Open No. 2010-186940, Japanese Patent Application Laid-Open No. 2012-142378, Japanese Patent Application Laid-Open No. 2011-82375

[0004] The present specification aims to ensure that component mounting work is performed appropriately.

[0005] In order to solve the above problems, this specification discloses a component mounting machine that includes a holding device that holds a board and a mounting head that mounts components on the board held by the holding device, and that detects the height of the component mounted on the board and lowers the board if it determines that the component and the mounting head will interfere with each other based on the detected component height, which is the component detection height.

[0006] Furthermore, in order to solve the above-mentioned problems, this specification discloses a production system for producing boards in which a plurality of the above-mentioned component mounting machines are arranged, and a board is transported from one arranged upstream of the plurality of component mounting machines to one arranged downstream of the plurality of component mounting machines, while each of the plurality of component mounting machines sequentially performs component mounting work on the board, and in which, when it is determined that a component will interfere with the mounting head in one of the plurality of component mounting machines, the holding device in the component mounting machine arranged downstream of the one of the plurality of component mounting machines transports the board downstream without clamping the board.

[0007] The component mounting machine disclosed herein detects the height of a component mounted on a board and, if it determines based on the detected component height that the component will interfere with the mounting head, lowers the board. This prevents interference between the component and the mounting head, ensuring proper mounting operations. Furthermore, in the production system disclosed herein, if it determines that interference between the component and the mounting head will occur in one of multiple component mounting machines, a holding device in a component mounting machine located downstream of the first component mounting machine conveys the board downstream without clamping the board. This prevents interference between the component and the mounting head in the component mounting machine located downstream of the first component mounting machine, ensuring proper mounting operations.

[0008] FIG. 1 is a diagram illustrating a mounting system; FIG. 2 is a diagram illustrating a placement machine provided in the mounting system; FIG. 3 is a diagram illustrating a conveying device provided in the mounting machine; FIG. 4 is a diagram illustrating a conveying device provided in the mounting machine; FIG. 5 is a diagram illustrating a placement head that places electronic components on a circuit board; FIG. 6 is a diagram illustrating a board discharger provided in the mounting system; FIG. 7 is a diagram illustrating a board discharger provided in the mounting system; FIG. 8 is a block diagram illustrating a control device provided in the mounting system; FIG. 9 is a diagram illustrating a placement head that places electronic components on a circuit board; FIG. 10 is a diagram illustrating an actual height and a threshold height of an electronic component; FIG. 11 is a diagram illustrating a state in which the circuit board has been lowered.

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings as modes for carrying out the present invention.

[0010] FIG. 1 shows an electronic component mounting system (hereinafter abbreviated as "mounting system") 10 according to an embodiment of the present invention. The mounting system 10 is a system for mounting electronic circuit components (hereinafter abbreviated as "electronic components") on a circuit board. The mounting system 10 comprises seven work machines: six electronic component placement machines (hereinafter sometimes abbreviated as "placement machines") 12, 14, 16, 18, 20, and 22, and one board discharge machine 24. The seven work machines are arranged in the following order from upstream: placement machine 12, placement machine 14, placement machine 16, placement machine 18, board discharge machine 24, placement machine 20, and placement machine 22. In the following description, the direction in which the seven work machines are lined up is referred to as the X-axis direction, the horizontal direction perpendicular to the X-axis direction is referred to as the Y-axis direction, and the direction perpendicular to the X-axis and Y-axis directions is referred to as the Z-axis direction.

[0011] First, we will explain the placement machines 12, 14, 16, 18, 20, and 22. Since the seven placement machines 12, 14, 16, 18, 20, and 22 have substantially the same configuration, we will explain the placement machine 12 as a representative. As shown in Figure 2, the placement machine 12 includes a transport device 30, a moving device 32, a placement head 34, and a supply device 36.

[0012] The transport device 30 is disposed on the upper surface of the base 40 of the placement machine 12, and as shown in Figures 2 and 3, has a conveyor device 50 and a substrate holding device 52. The conveyor device 50 has a pair of guide rails 60, 62 and a conveyor belt 66 attached to each of the guide rails 60, 62. The pair of guide rails 60, 62 are disposed parallel to each other, and each guide rail 60, 62 is supported on the upper surface of a support plate 72 via a pair of support legs 70. The guide rails 60, 62 are disposed to extend in the X-axis direction.

[0013] Two pulleys 74, 76 are disposed on the side of each guide rail 60, 62, with their axes aligned in the Y direction. These two pulleys 74, 76 are disposed at both ends of each guide rail 60, 62. The guide rails 60 and 62 are disposed such that the surfaces on which the pulleys 74, 76 are disposed face each other. A conveyor belt 66 is wound around the pulleys 74, 76 of each guide rail 60, 62, and is rotated by the drive of an electromagnetic motor 78 (see FIG. 9).

[0014] The conveyor belt 66 rotates clockwise in Fig. 3. As a result, when a circuit board (see Fig. 2) 80 is placed on the conveyor belt 66, the circuit board 80 is transported by the conveyor belt 66 from the side where the pulley 74 is provided to the side where the pulley 76 is provided.

[0015] The substrate holding device 52 also has a lift table 86, a plurality of backup pins 88, a table lifting mechanism 90, and a clamping mechanism 92. The lift table 86 is generally rectangular and is disposed below the guide rails 60, 62 so as to extend between the pair of support legs 70 of each guide rail 60, 62. A plurality of backup pins 88 are arranged in a 3×3 array, for example, on the upper surface of the lift table 86. The lift table 86 is disposed on the upper surface of the support plate 72 via a table lifting mechanism 90, and the table lifting mechanism 90 raises and lowers the lift table 86 by driving an electromagnetic motor 96 (see FIG. 9 ).

[0016] The clamp mechanism 92 also includes a pair of clamp bars 100 and a pair of clamp plates 102. The clamp bars 100 are generally plate-shaped, and the length of the clamp bars 100 is longer than the length of the lift table 86 in the X direction. Each of the pair of clamp bars 100 is fixed to the upper surfaces of the guide rails 60, 62 so that the lift table 86 is located between both ends of the clamp bar 100. In other words, the clamp bars 100 are fixed to the upper surfaces of the guide rails 60, 62 so that the lift table 86 extends below the clamp bars 100. The clamp bars 100 are fixed to the upper surfaces of the guide rails 60, 62 so that they extend above the conveyor belt 66 disposed on the guide rails 60, 62.

[0017] The clamp plate 102 is generally rectangular, and its longitudinal length is approximately the same as that of the clamp bar 100. The clamp plate 102 extends in the same direction as the clamp bar 100, below the clamp bar 100, which extends above the conveyor belt 66, and is held upright by the guide rails 60, 62 so as to be slidable in the vertical direction. That is, a holder 108 is disposed on the side of the guide rails 60, 62 on the side where the conveyor belt 66 is disposed. The clamp plate 102 is held by the holder 108 below the clamp bar 100 so as to be slidable in the vertical direction, with the side surfaces of the guide rails 60, 62 facing the side surface of the clamp plate 102.

[0018] When the clamp plate 102, which is held by the guide rails 60, 62 so as to be able to slide vertically, slides to the lowest position, as shown in Figure 4, the upper end of the clamp plate 102 is located below the upper surface of the conveyor belt 66, and the lower end of the clamp plate 102 is located above the upper surface of the lift table 86 when it is not raised.

[0019] With this structure, in the transfer device 30, the circuit board 80 transferred by the conveyor device 50 is clamped by the board holding device 52. More specifically, the circuit board 80 is carried into the placement machine 12 and then transferred to a predetermined work position by the conveyor device 50. When the circuit board 80 is transferred to the work position, both edges of the circuit board 80 placed on the conveyor belt 66 of the conveyor device 50 are positioned between the clamp bar 100 and the clamp plate 102 in the vertical direction, as shown in FIG.

[0020] Next, when the circuit board 80 is transported to the work position, the table lifting mechanism 90 is operated to lift the lift table 86. At this time, the lower end of the clamp plate 102 comes into contact with the upper surface of the lift table 86, and as the lift table 86 rises, the clamp plate 102 also rises. As the clamp plate 102 rises, the upper end of the clamp plate 102 comes into contact with the underside of the circuit board 80 supported by the conveyor belt 66. The height dimension of the backup pin 88 placed on the upper surface of the lift table 86 is the same as the vertical length dimension of the clamp plate 102.

[0021] Therefore, at the same time that the upper end of the clamp plate 102 comes into contact with the underside of the circuit board 80 supported by the conveyor belt 66, the upper ends of the backup pins 88 also come into contact with the underside of the circuit board 80. Then, as the lift table 86 rises, the circuit board 80 supported by the conveyor belt 66 is lifted up from the conveyor belt 66 by the clamp plate 102 and the backup pins 88. At this time, as shown in FIG. 5 , the table lifting mechanism 90 operates, and the circuit board 80 is lifted up by the clamp plate 102 and the backup pins 88 to a position where the upper surface of the circuit board 80 comes into contact with the underside of the clamp bar 100. As a result, the circuit board 80 is clamped at both edges between the clamp bar 100 and the clamp plate 102, with the central portion of the circuit board 80 supported from below by the backup pins 88.

[0022] As shown in FIG. 2 , the moving device 32 is composed of an X-axis slide mechanism 110, a Y-axis slide mechanism 112, and a Z-axis slide mechanism 114. The X-axis slide mechanism 110 has an X-axis slider 116 mounted on the base 40 so as to be movable in the X-axis direction. The X-axis slider 116 is moved to a desired position in the X-axis direction by driving an electromagnetic motor (see FIG. 9 ) 118. The Y-axis slide mechanism 112 has a Y-axis slider 120 mounted on a side of the X-axis slider 116 so as to be movable in the Y-axis direction. The Y-axis slider 120 is moved to a desired position in the Y-axis direction by driving an electromagnetic motor (see FIG. 9 ) 122. The Z-axis slide mechanism 114 has a Z-axis slider 124 mounted on a side of the Y-axis slider 120 so as to be movable in the Z-axis direction. The Z-axis slider 124 is moved to a desired position in the Z-axis direction by driving an electromagnetic motor (see FIG. 9 ) 126. The mounting head 34 is attached to the Z-axis slider 124. With this structure, the mounting head 34 can be moved to any position on the base 40 by the X-axis slide mechanism 110 and the Y-axis slide mechanism 112, and can be raised and lowered in the vertical direction by the Z-axis slide mechanism 114.

[0023] The placement head 34 places electronic components on the circuit board 80. The placement head 34 has a suction nozzle 130 provided on its bottom surface. The suction nozzle 130 is connected to a positive / negative pressure supply device (see FIG. 9) 132 via negative pressure air and positive pressure air passages. The suction nozzle 130 sucks and holds electronic components using negative pressure, and releases the held electronic components using positive pressure. The placement head 34 also has an expansion / contraction mechanism (see FIG. 6) 136 that expands and contracts when placing electronic components on the circuit board 80. Therefore, when the placement head 34 places electronic components on the circuit board 80, the expansion / contraction mechanism 136 contracts, thereby reducing the load applied to the electronic components when the electronic components come into contact with the circuit board 80.

[0024] The placement head 34 also includes a contact sensor 138 (see FIG. 9 ), which outputs an ON signal when the extension / contraction mechanism 136 contracts by a predetermined amount. That is, when the placement head 34 places an electronic component on the circuit board 80, the electronic component comes into contact with the circuit board 80, causing the extension / contraction mechanism 136 to contract by a predetermined amount, thereby causing the contact sensor 138 to output an ON signal. Therefore, by calculating the position of the placement head 34 in the Z-axis direction when the contact sensor 138 outputs the ON signal, the height of the electronic component placed on the circuit board 80 (hereinafter referred to as the "component detection height") can be detected. That is, as shown in FIG. 6 , when the placement head 34 places an electronic component 150 on the circuit board 80, the electronic component 150 comes into contact with the circuit board 80, causing the extension / contraction mechanism 136 to contract by a predetermined amount, causing the contact sensor 138 to output an ON signal. The position of the tip of the suction nozzle 130 of the placement head 34 in the Z-axis direction when the contact sensor 138 outputs the ON signal is then calculated. The calculated tip position of the suction nozzle 130 is detected as the component detection height KL of the electronic component 150 .

[0025] Furthermore, a height sensor 152 is disposed facing downward on the underside of the Z-axis slider 124 to which the mounting head 34 is attached. The height sensor 152 detects the height of the upper surface of the circuit board 80 by emitting light downward and, for example, receiving light reflected by the circuit board 80. Therefore, by having the height sensor 152 detect the height of the upper surface of the circuit board 80 at multiple points on the circuit board 80, the amount of warpage of the circuit board 80 can be calculated.

[0026] As shown in FIG. 2 , the supply device 36 is a feeder-type supply device and includes a plurality of tape feeders 160. The tape feeders 160 accommodate tape-formed components in a wound state. The tape-formed components are electronic components that have been taped. The tape feeders 160 then feed out the tape-formed components using a feed device (see FIG. 9 ) 162. As a result, the feeder-type supply device 36 feeds out the tape-formed components to supply electronic components at the supply position.

[0027] Next, the board discharger 24 will be described. As shown in Figure 7, the board discharger 24 is equipped with two conveyor devices 170, 172. Each of the two conveyor devices 170, 172 has the same structure as the conveyor device 50 of the placement machine 12, and a pair of conveyor belts 176 are driven by an electromagnetic motor (see Figure 9) 178 to rotate, thereby transporting the circuit boards 80 placed on the pair of conveyor belts 176. The two conveyor devices 170, 172 are arranged to extend parallel to the X-axis direction.

[0028] Furthermore, the conveyor devices 170 and 172 are disposed on a base 182 via a branching device 180. The branching device 180 has a generally rectangular panel 184. The panel 184 is disposed on the base 182 with its longitudinal direction extending in the X-axis direction, and the two conveyor devices 170 and 172 are disposed on the upper surface of the panel 184. When distinguishing between the conveyor devices 170 and 172, the conveyor device 170 of the two conveyor devices 170 and 172 will be referred to as the first conveyor device 170 and the other conveyor device 172 of the two conveyor devices 170 and 172 will be referred to as the second conveyor device 172. The panel 184 is disposed on the base 182 so as to be slidable in the Y-axis direction, and is slid in the Y-axis direction by the drive of an electromagnetic motor (see FIG. 9 ) 188. As a result, the branching device 180 moves the conveyor devices 170 and 172 in the Y-axis direction, and branches the transported circuit board 80 to either the downstream placement machine 20 or a discharge position for discharge from the mounting system 10.

[0029] Specifically, the first conveyor device 170 is normally connected to the conveyor device 50 of the placement machine 18 upstream of the board discharger 24 and the conveyor device 50 of the placement machine 20 downstream of the board discharger 24. For this reason, the circuit board 80 is normally carried from the conveyor device 50 of the placement machine 18 to the first conveyor device 170 of the board discharger 24, and is carried out from the first conveyor device 170 of the board discharger 24 to the conveyor device 50 of the placement machine 20. However, as will be described in detail later, if the circuit board 80 is determined to be an NG board, when the NG board is carried from the conveyor device 50 of the placement machine 18 to the first conveyor device 170 of the board discharger 24, a panel 184 is moved in the Y-axis direction by the operation of the branching device 180, as shown in FIG. As a result, the second conveyor device 172 is connected to the conveyor device 50 of the placement machine 18 upstream of the board discharger 24 and the conveyor device 50 of the placement machine 20 downstream of the board discharger 24. At this time, the first conveyor device 170 moves to a position where the conveyor device 50 of the placement machine 18 and the conveyor device 50 of the placement machine 20 are disconnected. This position is the discharge position, and the worker can discharge the defective board from the mounting system 10 using the first conveyor device 170 that has moved to the discharge position. In other words, when the panel 184 is moved to the position shown in FIG. 7 by the operation of the branching device 180, the first conveyor device 170 transports the circuit board 80 to the conveyor device 50 of the downstream placement machine 20. Meanwhile, when the panel 184 is moved to the position shown in FIG. 8 by the operation of the branching device 180, the first conveyor device 170 moves to the discharge position, and the worker discharges the circuit board 80 from the mounting system 10 using the first conveyor device 170. In this way, the branching device 180 branches the transported circuit board 80 to either the downstream placement machine 20 or the discharge position for discharging the circuit board 80 from the mounting system 10 .

[0030] 9, the mounting system 10 also includes a control device 190. The control device 190 includes a controller 192 and a plurality of drive circuits 196. The plurality of drive circuits 196 are connected to the electromagnetic motors 78, 96, 118, 122, 126, 178, and 188, the positive and negative pressure supply device 132, and the discharge device 162. The controller 192 is primarily a computer and includes a CPU, ROM, RAM, and the like, and is connected to the plurality of drive circuits 196. This allows the controller 192 to control the operation of the placement machines 12, 14, 16, 18, 20, and 22 and the substrate discharge machine 24. The controller 192 is also connected to the contact sensor 138 and the height sensor 152, and acquires the detection values ​​of the contact sensor 138 and the height sensor 152.

[0031] With the above-described configuration, in the mounting system 10, the circuit board 80 is transported from the placement machine 12 located on the most upstream side to the placement machine 22 located on the most downstream side. The placement machines 12, 14, 16, 18, 20, and 22 perform the placement work on the transported circuit board 80, and the mounting system 10 produces circuit boards on which electronic components are mounted.

[0032] Specifically, in the placement machine 12, the conveyor device 50 first conveys the circuit board 80 to the work position in response to a command from the control device 190, where the board holding device 52 clamps the circuit board 80. Next, in response to a command from the control device 190, the placement head 34 moves to above the supply position of the supply device 36 and sucks and holds electronic components from the supply device 36. Subsequently, in response to a command from the control device 190, the placement head 34 moves above the circuit board 80 and places electronic components on the circuit board 80. When the placement operation in the placement machine 12 is completed, the board holding device 52 releases the clamp on the circuit board 80, and the conveyor device 50 transports the circuit board 80 toward the placement machine 14. This placement operation is sequentially performed by the placement machines 14, 16, 18, 20, and 22, thereby producing circuit boards with electronic components mounted thereon. In this description, the branching device 180 in the board discharger 24 branches the circuit board 80 to the downstream placement machine 20. In other words, in the board discharger 24, the panel 184 is moved to the position shown in Figure 7 by the operation of the branching device 180, and the conveyor device 50 of the mounting machine 18 transports the circuit board 80 to the first conveyor device 170 of the board discharger 24, and the first conveyor device 170 of the board discharger 24 transports the circuit board 80 to the conveyor device 50 of the mounting machine 20.

[0033] In this way, by performing the mounting operation on each of the placement machines 12, 14, 16, 18, 20, and 22, a circuit board with electronic components mounted thereon is produced. However, there are cases where the electronic components are not properly mounted on each placement machine. Specifically, for example, as shown in FIG. 10 , a foreign object 198 may have fallen onto the circuit board 80, and the electronic component 200 may be mounted on the foreign object 198. In such a case, the electronic component 200 mounted on the circuit board 80 is tilted, and the mounting height of the electronic component 200 when the placement head 34 places the electronic component 200 is higher than the actual height of the electronic component 200. In other words, as shown in FIG. 11 , if the electronic component 200 is mounted on the circuit board 80 without any foreign object or the like, the mounting height of the electronic component 200 when the placement head 34 places the electronic component 200 is the actual height RL of the electronic component 200. The actual height RL of the electronic component is stored in the controller 192. 10 , when electronic component 200 is placed on circuit board 80 with foreign object 198 sandwiched therebetween, the placement height of electronic component 200 when placement head 34 places electronic component 200 will be higher than actual height RL of electronic component 200 by a distance corresponding to the height of foreign object 198. Note that the placement height of electronic component 200 when placement head 34 places electronic component 200 is the component detection height KL, which is the tip position of suction nozzle 130 when placement head 34 places electronic component 200 on circuit board 80 and is calculated when contact sensor 138 outputs an ON signal. Therefore, when component detection height KL is higher than actual height RL of electronic component 200, it is determined that electronic component 200 was placed at an angle.

[0034] Furthermore, in the placement machines 12, 14, 16, 18, 20, and 22, the placement head 34 is raised and lowered by operation of the Z-axis slide mechanism 114, and the range of elevation of the placement head 34 by the Z-axis slide mechanism 114 is naturally defined, and as shown in FIG. 12 , an ascent limit position 210 of the placement head 34 is defined. The ascent limit position 210 of the placement head 34 is the bottom end of the placement head 34 when it is at its highest point, i.e., the position of the bottom end of the suction nozzle 130. For this reason, the upper limit height GL of electronic components 212 that can be placed by the placement machines 12, 14, 16, 18, 20, and 22 is set to be lower by the clearance CL than the ascent limit position 210 of the placement head 34. In other words, the placement machines 12, 14, 16, 18, 20, and 22 are set to only accept electronic components that are equal to or lower than the upper limit height GL as components to be placed. However, even for electronic components that are equal to or less than the upper limit height GL, as described above, if the component detection height KL is higher than the actual height RL of the electronic component, i.e., if the electronic component is mounted on the circuit board 80 at an angle, the component detection height KL may exceed the upper limit height GL. In such a case, as the mounting head 34 moves in the X and Y directions, there is a risk that the component detection height KL may interfere with the electronic component that exceeds the upper limit height GL. Therefore, a worker must remove the circuit board on which such an electronic component is mounted from the mounting machine. However, considering that a worker must remove the circuit board from the mounting machine, it becomes difficult to achieve automation and labor-saving in factories.

[0035] In consideration of this, the threshold height SL is set based on the upper limit height GL, and if the component detection height KL exceeds the threshold height SL, the circuit board 80 is determined to be an NG board. Specifically, the controller 192 calculates the component detection height KL based on the detection value of the contact sensor 138 each time the mounting head 34 places an electronic component on the circuit board 80. The controller 192 also stores the actual height RL of the electronic component to be placed. Therefore, the controller 192 determines whether the component detection height KL exceeds the actual height RL. If the component detection height KL exceeds the actual height RL, it is assumed that the electronic component was placed on the circuit board 80 at an angle, and the controller 192 determines whether the component detection height KL exceeds the threshold height SL. The threshold height SL is set to a height between the upper limit height GL and the lift limit position 210, as shown in FIG. 12 . Then, as shown in FIG. 10, when the component detection height KL exceeds the threshold height SL, there is a risk of interference between the mounting head 34 and the electronic component 200, and therefore the controller 192 determines the circuit board 80 to be an NG board.

[0036] In this way, when the controller 192 determines that the circuit board 80 is a defective board, it outputs a command to the board holding device 52 to release the clamp on the circuit board 80. As a result, the board holding device 52 lowers the circuit board 80 by operating the table lifting mechanism 90, thereby releasing the clamp on the circuit board 80. That is, during the mounting operation, as shown in FIG. 5 , the circuit board 80 is clamped by being sandwiched between the clamp plate 102 and the clamp bar 100. Then, as shown in FIG. 4 , the lifting table 86 is lowered by operating the table lifting mechanism 90, and the circuit board 80 is lowered, and the clamp on the circuit board 80 by the clamp plate 102 and the clamp bar 100 is released. When the circuit board 80 is lowered in this way, as shown in FIG. 13 , the electronic component 200 mounted on the circuit board 80 also lowers, and the upper end of the electronic component 200 and the lower end of the mounting head 34 are spaced apart in the vertical direction, thereby preventing interference between the mounting head 34 and the electronic component 200.

[0037] Then, when the clamp of the circuit board 80 determined to be an NG board is released, the circuit board 80 is transported by the conveyor device 50 toward the downstream placement machine. This allows the circuit board 80 determined to be an NG board to be automatically removed from the placement machine. Note that if the circuit board 80 determined to be an NG board is transported to the downstream placement machine, clamped there, and placement work is performed, there is a risk of interference between the placement head 34 and the electronic components 200. For this reason, in the placement machine downstream of the placement machine where the circuit board 80 was determined to be an NG board, the NG board is transported downstream without being clamped. Then, the branching device 180 branches the NG board to the discharge position rather than branching it to the downstream placement machine.

[0038] Specifically, for example, when the placement machine 14 determines that the circuit board 80 is a defective board, the controller 192 outputs a command to the placement machines 16 and 18 downstream of the placement machine 14 to "convey the circuit board 80 determined to be a defective board downstream without clamping it." Furthermore, the controller 192 outputs a command to the board discharge machine 24 to "branch the circuit board 80 determined to be a defective board to the discharge position." Then, the placement machines 16 and 18 convey the circuit board 80 determined to be a defective board downstream in accordance with the command from the controller 192. Furthermore, the board discharge machine 24 branches the circuit board 80 determined to be a defective board to the discharge position. This makes it possible to prevent interference between the placement heads 34 and electronic components 200 even in the placement machines 16 and 18 downstream of the placement machine 14 where the circuit board 80 was determined to be a defective board. Furthermore, by discharging the defective substrate to the discharge position in the substrate discharger 24, it becomes possible to continue mounting work in the mounting system 10 without the need for a worker to retrieve the defective substrate, which promotes automation and labor-saving in factories.

[0039] In some cases, warpage may occur in the circuit board 80 held by the board holding device 52 in the placement machine. In such cases, the height of the upper surface of the circuit board 80 varies for each circuit board held by the board holding device 52. In consideration of this, the threshold height SL may be set based on the upper limit height GL and the amount of warpage of the circuit board. Specifically, each time the board holding device 52 holds a circuit board, the height sensor 152 detects the height of the upper surface of the circuit board at multiple locations on the circuit board, and the amount of warpage of the circuit board is calculated. The threshold height SL is then set based on the upper limit height GL and the amount of warpage of the circuit board. For example, if the circuit board is warped in a convex shape, the threshold height SL is calculated by adding the amount of warpage of the circuit board to the upper limit height GL. On the other hand, if the circuit board is warped in a concave shape, the threshold height SL is calculated by subtracting the amount of warpage of the circuit board from the upper limit height GL. In this way, calculating the threshold height SL while also taking the amount of warpage of the circuit board into consideration makes it possible to more effectively prevent interference between the placement head 34 and electronic components.

[0040] The mounting system 10 is an example of a production system. The placement machines 12, 14, 16, 18, 20, and 22 are examples of component placement machines. The placement head 34 is an example of a placement head. The board holding device 52 is an example of a holding device. The circuit board 80 is an example of a board. The extension mechanism 136 is an example of an extension mechanism. The branching device 180 is an example of a branching device. The electronic component 200 is an example of a component.

[0041] As described above, the present embodiment has the following advantages.

[0042] In the above embodiment, the component detection height KL of the electronic component 200 mounted on the circuit board 80 is detected, and if it is determined based on the component detection height KL that the electronic component 200 will interfere with the mounting head 34, the controller 192 lowers the circuit board 80. This prevents interference between the electronic component 200 and the mounting head 34.

[0043] Furthermore, if it is determined based on the component detection height KL that the electronic component 200 and the mounting head 34 will interfere with each other, the controller 192 lowers the circuit board 80 to release the clamp on the circuit board 80. This allows the circuit board 80 to be easily lowered in the board holding device 52 that raises the circuit board 80 to clamp it.

[0044] Furthermore, the component detection height KL is detected when the mounting head 34 mounts the electronic component on the circuit board 80. This makes it possible to easily detect the component detection height KL.

[0045] The placement head 34 is also provided with an extension / contraction mechanism 136 that contracts when the placement head 34 places electronic components on the circuit board 80, and a contact sensor 138 outputs an ON signal when the extension / contraction mechanism 136 contracts a predetermined amount. The component detection height KL is then detected based on the position of the placement head 34 in the Z-axis direction when the contact sensor 138 outputs the ON signal. In other words, the component detection height KL is detected based on the amount of expansion / contraction of the extension / contraction mechanism 136. This allows the component detection height KL to be detected using a simple mechanism.

[0046] Furthermore, a threshold height SL is set based on the upper limit height GL, and when the component detection height KL exceeds the threshold height SL, it is determined that there is interference between the mounting head 34 and the electronic component 200. This makes it possible to appropriately determine whether or not there is interference between the mounting head 34 and the electronic component 200.

[0047] The threshold height SL is set based on the upper limit height GL and the amount of warpage of the circuit board, thereby making it possible to more appropriately determine whether or not there is interference between the mounting head 34 and the electronic component.

[0048] Furthermore, in the mounting system 10, when it is determined that interference will occur between the placement head 34 and the electronic components 200 in one of the multiple placement machines, the transport device 30 in the placement machine located downstream of the first placement machine transports the circuit board downstream without clamping it. This makes it possible to prevent interference between the placement head 34 and the electronic components 200 in the placement machine located downstream of the first placement machine as well.

[0049] Furthermore, the mounting system 10 is provided with a board ejector 24, and a branching device 180 of the board ejector 24 branches to a discharge position a defective board that is determined to cause interference between the mounting head 34 and the electronic component 200. This allows the mounting work to continue in the mounting system 10 without the operator having to retrieve the defective board.

[0050] The present disclosure is not limited to the above-described embodiment, and various modifications and improvements can be made based on the knowledge of those skilled in the art. Specifically, in the above-described embodiment, if the component detection height KL is higher than the actual height RL of the electronic components and exceeds the threshold height SL, the controller 192 identifies the circuit board as an NG board. On the other hand, if the component detection height KL exceeds the threshold height SL without comparing the component detection height KL with the actual height RL of the electronic components, the circuit board may be identified as an NG board.

[0051] Furthermore, in the above embodiment, the mounting system 10 is provided with a substrate discharger 24, and the NG substrate is discharged to a discharge position by the substrate discharger 24. On the other hand, if the mounting system 10 is not provided with the substrate discharger 24, the circuit board determined to be an NG substrate may be transported to the most downstream placement machine 22. In such a case, in all placement machines downstream of the placement machine in which the circuit board is determined to be an NG substrate, the transport device 30 transports the circuit board downstream without clamping it.

[0052] Furthermore, in the above embodiment, the component detection height KL is detected based on the detection value of the contact sensor 138, but the component detection height KL may also be detected based on the detection values ​​of various sensors such as the height sensor 152.

[0053] Furthermore, in the above embodiment, the mounting head 34 moves in the X and Y directions to perform the component mounting operation, but the clamped circuit board 80 may also move in the X and Y directions to perform the component mounting operation.

[0054] Furthermore, in the above embodiment, a board holding device 52 is used that clamps the circuit board when the circuit board is raised and releases the clamp when the circuit board is lowered, but a board holding device that clamps and releases the clamp of the circuit board at a predetermined height may also be used.

[0055] Furthermore, in the above embodiment, electronic components are used as components mounted on the circuit board, but the components are not limited to electronic components and various other components can be used.

[0056] 10: Mounting system (production system) 12: Placement machine (component placement machine) 14: Placement machine (component placement machine) 16: Placement machine (component placement machine) 18: Placement machine (component placement machine) 20: Placement machine (component placement machine) 22: Placement machine (component placement machine) 34: Placement head 52: Board holding device (holding device) 80: Circuit board (board) 136: Extension mechanism 180: Branching device 200: Electronic component (component)

Claims

1. A component mounting machine comprising a holding device for holding a board and a mounting head for mounting components onto the board held by said holding device, which detects the height of a component mounted on the board and lowers the board if it determines that the component and said mounting head will interfere with each other based on the detected component height, known as the component detection height.

2. A component mounting machine as described in claim 1, wherein the holding device clamps the board when the board is raised and releases the clamp when the board is lowered, and lowers the board to release the clamp when it is determined that the component and the mounting head will interfere with each other.

3. The component mounting machine according to claim 1, wherein the component detection height is detected when the mounting head mounts components on the board.

4. A component mounting machine as described in claim 3, wherein the mounting head has an extension / contraction mechanism that expands and contracts when mounting components on a board, and the component detection height is detected based on the amount of expansion / contraction of the extension / contraction mechanism.

5. A component mounting machine as described in claim 1, wherein an upper limit height of components that can be mounted by the component mounting machine is set, and when the component detection height exceeds a threshold value set based on the upper limit height, it is determined that the component and the mounting head will interfere with each other.

6. A component mounting machine according to claim 5, wherein the threshold value is set based on the upper limit height and the amount of warping of the board held by the holding device.

7. A production system for producing boards in which a plurality of component mounting machines as set forth in any one of claims 2 to 6 are arranged, and a board is transported from one located upstream of the plurality of component mounting machines to one located downstream, while components are sequentially mounted on the board by each of the plurality of component mounting machines, wherein, when it is determined that a component will interfere with the mounting head in one of the plurality of component mounting machines, the holding device in the component mounting machine located downstream of the one of the plurality of component mounting machines transports the board downstream without clamping the board.

8. A production system as described in claim 7, further comprising a branching device disposed downstream of the first component mounting machine, which branches the transported board to either a further downstream component mounting machine or a discharge position for discharging the board from the production system, and wherein a board determined by the first component mounting machine to have components interfering with the mounting head is diverted to the discharge position by the branching device.

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