JP4342064B2 - Component mounting method and component mounting apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a component mounting method and a component mounting apparatus for mounting a component provided with a board fixing means on a circuit board.
[0002]
[Prior art]
In recent years, electronic circuit boards on which various parts (for example, electronic parts) are mounted have individual parts mounted on the circuit board by automation in order to increase productivity. In such a component mounting apparatus for mounting an electronic component on a circuit board, when mounting the electronic component on the circuit board, it is possible to control a good mounting state and mounting completion by applying a pressing force to the component. There is something that was made.
[0003]
In this type of component mounting apparatus, a nozzle 3 for adsorbing the electronic component 1 shown in FIG. 10 is provided at the tip of a shaft 5, and the shaft 5 is configured to be movable up and down in the axial direction by a voice coil motor (not shown). . The voice coil motor moves the shaft 5 in the axial direction when an electric current is applied. Further, the pressure applied to the electronic component 1 can be known by detecting the current flowing through the voice coil motor.
[0004]
In the procedure of the component mounting method using such a conventional component mounting apparatus, as shown in FIG. 11, first, the electronic component 1 sucked and held by the nozzle 3 is lowered (st1), and a position where it hits the circuit board 7 ( When the hit detection start position) is reached, the torque of the voice coil motor suddenly increases. When this torque value reaches the detection torque value (threshold value) shown in FIG. 12, it is determined that the electronic component 1 has reached the circuit board 7 (st3), and weighting to the electronic component 1 is started. (St5).
[0005]
Next, it is determined whether or not the detected torque has reached a preset weighted torque. If the detected torque is less than the set weighted torque, the electronic component 1 continues to be weighted. On the other hand, when the detected torque exceeds the set weight torque, the weight is maintained for the set time, and the electronic component 1 is mounted on the circuit board 7. After the elapse of the weight setting time, the nozzle 3 is raised to the return position, and the mounting operation of the electronic component 1 on the circuit board 7 is completed.
[0006]
[Problems to be solved by the invention]
However, in the conventional component mounting method, only the detection torque value is determined based on fluctuations in the current value of the voice coil motor, and the detection torque value is fixed at a constant value. When a component provided with a fixing means that is engaged with the fixing portion is mounted on a circuit board on which the fixing portion is formed, a pressing force applied to the component causes the fixing means and the fixing portion to be engaged. A misjudgment that a component has been mounted occurs before reaching a certain pressing force at the time of combination, and the mounting operation of the component on the circuit board is performed even though the fixing means and the fixing portion are not engaged. Could end. Further, since the hit detection torque value is fixed at a constant value, the mounting operation cannot be applied to various parts having different pressing forces.
The present invention has been made in view of the above situation, and can prevent misjudgment that a component has been mounted before the engagement of the component is completed, and can mount various components. Therefore, the purpose is to improve the reliability of the component mounting operation and to improve the ability to mount various components.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention for achieving the above object, there is provided a component mounting method according to the present invention, wherein a component provided with a fixing means that engages with a fixing portion by applying a constant pressing force is formed on the fixing portion. A component mounting method for mounting on a circuit board, wherein a torque value for detection for determining that the component has reached the circuit board is detected as a torque value of a pressing force applied to the component, It is determined that the mounting of the component to the circuit board is completed when the torque value for detection is detected and the height of the component from the circuit board is a predetermined mounting height value. It is characterized by doing.
[0008]
In this component mounting method, the per-detection torque value is set to be larger than a constant pressing force applied to the component, and the per-detection torque value is detected and the height of the component from the circuit board is the predetermined mounting height. When the value is satisfied, it is determined that the component has been mounted on the circuit board. Therefore, it is possible to prevent an erroneous determination that the component is mounted before the pressing force applied to the component reaches a certain pressing force when the fixing means and the fixing portion are engaged, and to ensure that the component having the fixing means is installed. It is engaged with the fixed part and can be mounted on the circuit board.
[0009]
The component mounting method according to claim 2 is characterized in that the hit detection torque value is variably set according to the constant pressing force which is different for each of various components.
[0010]
In this component mounting method, the per-detection torque value can be variably set according to a constant pressing force that is different for each of various components, and the capability of mounting various components is enhanced.
[0011]
According to a third aspect of the present invention, there is provided a component mounting apparatus for mounting a component provided with a fixing means that engages with a fixing portion when a constant pressing force is applied to the circuit board on which the fixing portion is formed. A transfer head that picks up the component and moves the component up and down, a pressure control unit that detects and controls the pressing force applied to the component that is in contact with the circuit board by the lowering operation of the transfer head, and a post-operation A position detection unit that acquires a current position of the transfer head, a torque value setting unit that can set an arbitrary hit detection torque value, a hit detection torque value from the pressing control unit, and the position detection unit And a main control unit that determines that the mounting of the component to the circuit board is completed when a predetermined mounting height value of the component from the circuit board is detected.
[0012]
In this component mounting apparatus, the pressing force applied to the component is obtained from the pressure control unit, and the current position of the transfer head, that is, the current position of the component is obtained from the position detection unit. Then, when the pressing force detected from the pressing control unit exceeds the detection torque value and the height detected from the position detecting unit matches (or becomes lower) the predetermined mounting height value of the component, The main controller determines completion of component mounting. Thereby, the component can be mounted on the circuit board in a state where the component fixing means is engaged with the fixing portion of the circuit board.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of a component mounting method and a component mounting device according to the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a perspective view showing an embodiment of a component mounting apparatus according to the present invention, FIG. 2 is an enlarged perspective view of a transfer head, FIG. 3 is a sectional view of the transfer head, and FIG. FIG. 5 is an exploded perspective view showing another example of the component and the circuit board, and FIG. 6 is a control system of the component mounting apparatus according to the present invention. FIG.
[0014]
As shown in FIG. 1, a guide rail 17 for a circuit board 15 is provided in the center of the upper surface of the base 13 of the component mounting device 11, and the circuit board 15 is separated from a loader unit 19 on one end side by a conveying belt of the guide rail 17. The electronic component is transported to the mounting position 21 and from the mounting position 21 to the unloader 23 on the other end side. Y tables 25 and 27 are provided on both sides of the upper surface of the base 13 above the circuit board 15, and an X table 29 is suspended between the two Y tables 25 and 27. In addition, a transfer head 31 is attached to the X table 29, so that the transfer head 31 can be moved in the XY plane.
[0015]
The transfer head 31 mounted on the XY robot 30 including the X table 29 and the Y tables 25 and 27 and freely moving on the XY plane (horizontal plane) is supplied by electronic components such as a resistor chip and a chip capacitor. A desired electronic component is sucked by a suction nozzle 37 from a part feeder 33 or a parts tray 35 to which a relatively large electronic component such as an IC or a connector such as SOP or QFP is supplied. It is configured so that it can be mounted in a position. Such an electronic component mounting operation is controlled by a control system (to be described later) shown in FIG. 6 based on a preset mounting program.
[0016]
A large number of parts feeders 33 are arranged in parallel at both ends of the guide rail 17, and each part feeder is attached with a tape-like part roll containing electronic parts such as a resistor chip and a chip capacitor. Yes. In addition, the part tray 35 can be loaded with a total of two trays 35a whose length is perpendicular to the guide rails 17, and each tray 35a slides toward the guide rails 17 according to the number of parts supplied. The component takeout position in the Y direction is kept constant. A relatively large electronic component such as QFP is placed on the tray 35a.
[0017]
On the side of the circuit board 15 positioned on the guide rail 17, a two-dimensional displacement (suction posture) of the electronic component sucked by the suction nozzle 37 is detected, and the position shift is canceled. A recognition device 39 is provided for correction on the mounting head 31 side.
[0018]
As shown in FIG. 2, the transfer head 31 includes a plurality of (four in this embodiment) mounting heads (first mounting head 41a, second mounting head 41b, third mounting head 41c, and fourth mounting head 41d). : Component holding means) are configured as a multiple head that is connected side by side. The four mounting heads 41a, 41b, 41c, and 41d have the same structure, and the suction nozzle 37, the actuator 43 for causing the suction nozzle to move up and down, and the motor for causing the suction nozzle 37 to perform zero rotation. 45, a timing belt 47, and a pulley 49.
[0019]
The suction nozzle 37 of each mounting head is replaceable, and the other suction nozzles are stored in advance in the nozzle stocker 51 on the base 13 of the component mounting device 11. The suction nozzle 37 includes, for example, an S size nozzle that sucks a microchip component of about 1.0 × 0.5 mm, an M size nozzle that sucks an 18 mm square QFP, and the like, depending on the type of electronic component to be mounted. Is done.
[0020]
As shown in FIG. 3, the actuator 43 is constituted by a voice coil motor. The actuator 43 includes a scale 55 for detecting the position of the shaft 53 in order from the top, a scale head 57 for detecting the position of the scale 55, a shaft 53 supported by the ball spline 59, and a suction nozzle 37 for sucking and mounting electronic components. Are connected in series.
[0021]
A magnet 61 is attached to the shaft 53, and a coil 63 is disposed outside the magnet 61. When a current is passed through the coil 63, a magnetic field is generated around the shaft 53. The shaft 53 to which the magnet 61 is attached by this magnetic field operates by obtaining thrust in the vertical direction. Since the suction nozzle 37 for sucking and mounting the electronic component is attached to the lower side of the shaft 53, it works in conjunction with the shaft 53.
[0022]
As shown in FIG. 4, as a component to be mounted by the transfer head 31, for example, an electronic component provided with a fixing means 67 that engages with the fixing portion 65 when a constant pressing force T (see FIG. 9) is applied. 69. Examples of the fixing portion 65 include a locking hole formed in the circuit board 15, and examples of the fixing means 67 include an elastic locking claw that locks in the locking hole.
[0023]
The electronic component 69 includes a connector with a clamp that is attached to the circuit board 15 by applying a constant pressing force, and a pin 73 shown in FIG. It may be a PGA (Pin grid array) 75 that is inserted into the PGA 75, or a CCGA in which the pin-like terminals 71 of the PGA 75 are formed in a ceramic column shape.
[0024]
As shown in FIG. 6, the control system 77 of the component mounting apparatus 11 includes a positioning unit 79 that controls the XY robot 30 and a push applied to the electronic component 69 that is in contact with the circuit board 15 by the lowering operation of the transfer head 31. A pressure control unit 81 that detects and controls pressure, a position detection unit 83 that acquires the current position of the transfer head 31 after operation, a torque value setting unit 84 that sets a hit detection torque value, and a pressure control unit 81 Mainly, it is determined that the mounting of the electronic component 69 to the circuit board 15 is completed when the detection torque value is detected and the position detection unit 83 detects the predetermined mounting height value of the electronic component 69 from the circuit board 15. And a control unit 85.
[0025]
The main control unit 85 sends position command values to the positioning unit 79 and the press control unit 81, and provides position feedback to the positioning unit 79 and the press control unit 81 based on the values detected by the position detection unit 83, respectively. Add return position correction.
[0026]
The operation of the component mounting apparatus 11 configured as described above will be described below.
7 is a plan view schematically showing the configuration of the component mounting apparatus according to the present invention, FIG. 8 is a flowchart showing an outline of the procedure of the component mounting method according to the present invention, and FIG. 9 is a component mounting method according to the present invention. It is the graph which showed the relationship between the torque value for hit detection, and a nozzle descending position.
[0027]
As shown in FIG. 7, when the circuit board 15 carried from the loader unit 19 of the guide rail 17 is transported to a predetermined mounting position 21, the transfer head 31 is moved in the XY plane by the XY robot and moved to the parts feeder. The desired electronic component is picked up from 33 or the parts tray 35, moved onto the posture recognition camera of the recognition device 39, the suction posture of the electronic component is confirmed, and the suction posture correction operation is performed. Thereafter, the electronic component 69 is mounted at a predetermined position on the circuit board 15.
[0028]
Each mounting head 41a, 41b, 41c, 41d is sucked when the electronic component 69 is sucked from the parts feeder 33 or the parts tray 35 by the suction nozzle 37 and when the electronic component 69 is mounted at a predetermined position of the circuit board 15. The nozzle 37 is lowered in the vertical direction (Z direction) from the XY plane. Further, according to the type of the electronic component 69, the suction nozzle 37 is appropriately replaced to perform the mounting operation.
[0029]
By repeatedly sucking the electronic component 69 and mounting the electronic component 69 on the circuit board 15, the mounting of the electronic component 69 on the circuit board 15 is completed. The circuit board 15 that has been mounted is unloaded from the mounting position 21 to the unloader unit 23, while a new circuit board is loaded into the loader unit 19, and the above operation is repeated.
[0030]
Here, when each electronic component 69 is mounted, a detection torque value is set in the torque value setting unit 84 in accordance with the type of the electronic component 69 (such as the presence or absence of the fixing means 67). At the same time, the height of the electronic component 69 from the circuit board 15 is set as a predetermined mounting height value.
[0031]
Therefore, as shown in FIG. 8, when the mounting of the electronic component 69 is started, the suction nozzle 37 is lowered, a pressing load is applied to the electronic component 69 (st11), and then the electronic component 69 hits the detection start position. It is confirmed whether or not it has been lowered (st13). That is, the main control unit 85 determines whether the current value detected by the pressing control unit 81 has reached a preset detected current value. When the detected current value is lower than a preset weighted current value, the main control unit 85 continues to send a signal to the pressing control unit 81 to continue pressing the electronic component 69 that has reached the circuit board 15. .
[0032]
On the other hand, if the detected current value exceeds the current value corresponding to the detection torque value Tk shown in FIG. 9, it is assumed that the fixing means 67 of the electronic component 69 has completed the engagement with the fixing portion 65 of the circuit board 15. Next, the mounting height of the electronic component 69 is detected (st15). The mounting height of the electronic component 69 is detected by the position detection unit 83 via the scale head 57, and the detected height of the electronic component 69 from the circuit board 15 is sent to the main control unit 85 and determined. (St17).
[0033]
The main control unit 85 detects that the pressing force detected by the pressing control unit 81 is greater than the detection torque value Tk, and the height of the electronic component 69 from the position detection unit 83 matches the predetermined mounting height value Hk ( On the condition that the electronic component 69 has been lowered, it is determined whether or not the electronic component 69 has been normally mounted (st19). On the other hand, when the detected height of the electronic component 69 is larger than the predetermined mounting height value Hk, it is determined that the fixing means 67 and the fixing portion 65 are not engaged, and it is determined that the electronic component 69 is not mounted (NG) ( st21).
[0034]
As described above, in the above-described component mounting method, the hit detection torque value Tk is set to be larger than the constant pressing force T for mounting the electronic component, and the hit detection torque value Tk is detected and the electronic component 69 is detected. When the height from the circuit board 15 satisfies the predetermined mounting height value Hk, the completion of mounting of the electronic component 69 is determined, so that the pressing force applied to the electronic component 69 causes the fixing means 67 and the fixing portion 65 to move. It is possible to prevent an erroneous determination that the electronic component 69 has been mounted before reaching the constant pressing force for engagement, and the electronic component 69 having the fixing means 67 is securely engaged with the fixing portion 65 so that the circuit board 15 is engaged. It becomes possible to attach to.
[0035]
In addition, since the hit detection torque value Tk can be variably set according to a constant pressing force that is different for each of various components, it is possible to increase the ability to mount various components.
[0036]
【The invention's effect】
As described above in detail, in the component mounting method according to the present invention, the hit detection torque value is set to be larger than a constant pressing force for determining that the component has reached the circuit board, and the hit detection torque value is detected. In addition, when the height of the component from the circuit board satisfies a predetermined mounting height value, it is determined that the mounting of the component to the circuit board is completed, so the pressing force applied to the component causes the fixing means and the fixing portion to It is possible to prevent erroneous determination that a component has been mounted before reaching a certain pressing force during engagement, and to ensure that a component having a fixing means is engaged with a fixed portion and mounted on a circuit board. Thus, the reliability of the component mounting operation can be improved. Further, if the hit detection torque value can be variably set according to a constant pressing force that is different for each of various parts, it is possible to increase the ability to mount various parts.
[0037]
The component mounting apparatus according to the present invention includes a pressing control unit that controls a pressing force applied to the component, a position detection unit that acquires a current position of the transfer head, a hit detection torque value and a position detected from the pressing control unit. A main control unit that determines that the mounting of the component is completed when the predetermined mounting height value of the component detected from the detection unit is satisfied, so that the component fixing means is engaged with the fixing unit of the circuit board. In this state, the component can be securely attached to the circuit board.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a component mounting apparatus according to the present invention.
FIG. 2 is an enlarged perspective view of a transfer head.
FIG. 3 is a cross-sectional view of a transfer head.
FIG. 4 is an exploded perspective view of a component provided with fixing means and a circuit board provided with a fixing portion.
FIG. 5 is an exploded perspective view showing another example of a component and a circuit board.
FIG. 6 is a block diagram of a control system of the component mounting apparatus according to the present invention.
FIG. 7 is a plan view schematically showing a configuration of a component mounting apparatus according to the present invention.
FIG. 8 is a flowchart showing an outline of a procedure of a component mounting method according to the present invention.
FIG. 9 is a graph showing the relationship between the detection torque value and the nozzle lowering position in the component mounting method according to the present invention.
FIG. 10 is a perspective view of components and a circuit board mounted by a conventional component mounting apparatus.
FIG. 11 is a flowchart showing an outline of a procedure of a conventional component mounting method.
FIG. 12 is a graph showing a relationship between a detection torque value and a nozzle lowering position in a conventional component mounting method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Component mounting apparatus 15 Circuit board 31 Transfer head 65 Fixing part 67 Fixing means 69 Electronic component (component)
81 Press control unit 83 Position detection unit 84 Torque value setting unit 85 Main control unit Hk Predetermined mounting height value T Constant detection torque value per constant pressing force Tk

Claims (3)

A component mounting method for mounting a component provided with a fixing means that engages with a fixing portion by applying a constant pressing force to a circuit board on which the fixing portion is formed,
A torque value for detection for determining that the component has reached the circuit board detected as a torque value of the pressing force applied to the component is set larger than the constant pressing force,
The hit detection torque value is detected, and when the height of the component from the circuit board detects a predetermined mounting height value, it is determined that the mounting of the component to the circuit board is completed. Component mounting method.   The component mounting method according to claim 1, wherein the hit detection torque value is variably set according to the constant pressing force that is different for each of various components. A component mounting device for mounting a component provided with a fixing means that engages with a fixed portion by applying a constant pressing force to a circuit board on which the fixed portion is formed,
A transfer head that picks up the component and moves the component up and down;
A pressure control unit that detects and controls the pressing force applied to the component that is in contact with the circuit board by the lowering operation of the transfer head; and
A position detector for acquiring a current position of the transfer head ;
A torque value setting unit capable of setting an arbitrary hit detection torque value;
It is determined that the mounting of the component to the circuit board is completed when a detection torque value is detected from the pressing control unit and a predetermined mounting height value of the component from the circuit board is detected from the position detection unit. A component mounting device comprising: a main control unit.

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