JPH0758495A - Electronic part mounting device and method for correcting electronic part mounting position - Google Patents

Abstract

PURPOSE:To highly accurately align an electronic part fitted with lead pins with a circuit pattern formed on a printed board at narrow pitches by providing an image pickup body within a heat-affected area and correcting the position of the electronic part. CONSTITUTION:A heating-pressurizing body for mounting an electronic part K on a printed board P by thermopression bonding the leads of the part K is provided near a suction nozzle which sucks and carries the part K and the image of a mark M for correcting the position is recgnized with a camera 13 for recognizing the position of the board provided near the heating- pressurizing body. Then the suck state of the part K is recognized with a camera 6 for recognizing a part. The recognized image information of the camera 13 and 6 is taken in and the variation with time of the relative position between the camera bodies is calculated. Based on the calculated variation of the relative position, the corrected amount of the mounting position of the part K is calculated and the part K is aligned with the mounting position of the part K.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component mounting apparatus for mounting electronic components on a printed circuit board, and to a method for correcting the mounting position of the electronic component on the printed circuit board.

[0002]

2. Description of the Related Art When an electronic component such as TCP (tape carrier package) is mounted on a printed circuit board, a circuit pattern is provided at a predetermined position of the printed circuit board, and lead pins protruding from the TCP are thermocompression bonded thereto. It is supposed to do.

Recently, there is a tendency to prepare a large number of TCP lead pins at a narrow pitch due to a demand for increased capacity. In the electrode pattern of the printed circuit board described above, a large number of electrodes are also formed at a narrow pitch. A circuit pattern is provided.

That is, I formed in a rectangular shape in plan view
A so-called four-way IC (Integrated Circu), which is a C component and has many lead pins protruding from each side (four sides).
it) tends to be heavily used.

It is necessary to accurately align all of a large number of lead pins of such electronic parts with the electrodes of the circuit pattern provided on the printed circuit board, which requires high precision, and depending on the degree of misalignment, it may be a defective product. You will be certified.

As one of the methods for alignment, electronic components to be mounted and a printed circuit board to which the electronic components are to be mounted are imaged by cameras which are different image capturing bodies and the images are captured. Then, there is a method for recognition by performing a comparison operation with a regular position stored in advance.

[0007]

By the way, an electronic component is supplied from a supply unit, and is adsorbed and held at the tip of an adsorption nozzle, which is an adsorbing / conveying body, and conveyed to a predetermined position on a printed circuit board. The nozzle is provided in the bonding head.

The bonding head is provided with not only the suction nozzle but also a heating / pressurizing member including a heating heater for thermocompression bonding the lead pin of the electronic component to the circuit pattern, and a pressurizing tool. A substrate position recognition camera, which is an image pickup body that recognizes a mark for alignment provided on the substrate, is provided.

Since the downsizing of the bonding head itself has been promoted, the substrate position recognizing camera is within the range affected by the heat of the heating / pressurizing body. That is, the temperature of the lens barrel of the camera is apt to rise, so that a non-negligible deviation of the optical axis may occur and accurate position recognition cannot be performed.

However, conventionally, since the change in the relative position between the cameras is not corrected, a shift amount is generated due to a change with time of thermal influence during mounting, and mounting accuracy during continuous operation is deteriorated. There is a defect.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical axis of an image pickup body on the premise that the image pickup body is arranged within a range affected by heat. An electronic component mounting device and electronic component mounting position capable of correcting the mounting position of an electronic component having a narrow-pitch lead pin in order to absorb the deviation and performing highly accurate positioning with respect to a circuit pattern formed on a printed circuit board. It is intended to provide a correction method.

[0012]

In the electronic component mounting apparatus of the present invention, an electronic component supplied from a supply unit is adsorbed by an adsorbing / conveying body, conveyed to a predetermined position on a printed circuit board and placed, and this adsorbing / conveying is performed. In the vicinity of the body, there is arranged a heating / pressurizing body which moves together with the suction conveyance body and is mounted by thermocompression bonding the lead pin of the electronic component placed at a predetermined position on the printed circuit board, and in the vicinity of the heating / pressurizing body. A first image pickup body that moves together with the suction conveyance body and the heating / pressurizing body and that recognizes the image of the alignment mark provided on the printed board and sends the alignment information of the printed board is disposed on the suction conveyance body. The second image pickup body recognizes the electronic component sucked and conveyed to the device, sends the suction posture of the electronic component, pass / fail judgment, and alignment information, and a recognition mark for position correction is provided at a position near the second image pickup body. Provide and correct this position The image of the recognition mark is captured by the first image pickup body, the amount of change in the relative position with respect to the second image pickup body over time is calculated, and based on the calculated amount of change in the relative position, A means for calculating the correction amount of the component mounting position was provided.

According to the electronic component mounting position correcting method of the present invention, a heating / pressurizing body for mounting the lead pin of the electronic component on the printed circuit board by thermocompression bonding is provided in the vicinity of the suction carrier for sucking and transporting the electronic component. An electronic component mounting apparatus having a first image pickup body for recognizing an image of an alignment mark of a printed circuit board within a range affected by heat of a pressurizing body, the position being separately provided in the first image pickup body. By recognizing the recognition mark for correction, recognizing the electronic component sucked and conveyed by the suction conveyance body by the second image pickup body, and capturing the recognition image information of the first image pickup body and the second image pickup body. , Calculating the amount of change in the relative position of each image pickup body over time, based on the calculated amount of change in the relative position, calculate the correction amount of the electronic component mounting position, and the position of the electronic component, Performs alignment correction of the mounting position of this electronic component

[0014]

According to the present invention, the recognition image information of the first image pickup body and the second image pickup body is taken in, the amount of change in the relative position of each image pickup body over time is calculated, and the calculated relative position is calculated. Based on the change amount of, calculate the correction amount of the electronic component mounting position,
The position alignment of the electronic component and the mounting position of the electronic component are corrected.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. It is an electronic component mounting apparatus as shown in FIG. On one side of the housing 1, a plurality of carrier stockers 2 ...
Are installed side by side, and an electronic part called TCP is housed therein. A punching portion 3 is provided adjacent to the carrier stocker 2 (not shown in the figure). The punching section 3 is composed of a support base for supporting the tape extended from the carrier stocker 2 and a die for punching an electronic component into a predetermined shape from the tape.

A component supply stage 5 is arranged adjacent to the punched section 3. A component recognition camera 6, which is a second image pickup body, is arranged at a predetermined distance from the component supply stage 5, and a bonding stage 7 is provided adjacent to the component recognition camera 6.
Is provided.

Posts 8 are erected on both sides of the component supply stage 5 and the bonding stage 7, and guide rails 9 are installed between the upper ends of the posts. A bracket 11 connected to a drive mechanism 10 is engaged with the guide rail 9 so as to be reciprocally movable along the rail 9.

A bonding head 12 and a board position recognition camera 13, which is a first image pickup body, are attached to the bracket 11. These parts supply stage 5
1 to the bonding head 12 mounted on the bracket 11 and the board position recognition camera 13 are detailed in FIG.

That is, on the component supply stage 5,
Electronic component K punched into the required shape by the punching section 3
Are sequentially supplied one by one and placed. The bonding head 12 is provided with a suction nozzle, which will be described later, to suck the electronic component K on the component supply stage 5. Then, by driving the drive mechanism 10,
The bracket 11 is moved from above the component supply stage 5 to above the bonding stage 7 to form the suction carrier 14.

A pin 16 is erected on a support base 15 for supporting the camera 6 for recognizing the component, and a recognition mark M for position correction is drawn on the upper end surface thereof. The printed circuit board P is placed on the bonding stage 7, and in this state, it can be slightly moved in a direction orthogonal to the guide rail 9. The bonding stage 7 is a stage rail 1 provided in a direction orthogonal to the guide rail 9.
It is supported by 7 and is movable from a substrate supply unit provided at one end to a substrate unloading unit provided at the other end. (Neither is shown) In the figure, 18 is a control unit,
It is electrically connected to each of the cameras 6 and 13 and electric parts described later, and receives necessary electric signals and sends control signals.

As shown in FIG. 2, the suction nozzle 20 attached to the bracket 11 is adapted to suck the electronic component K into the lower end opening thereof. And the suction nozzle 2
A radiator 21 and a heating / pressurizing tool 22 are provided around the 0 base end.
Are provided, and the heating and pressurizing body 23 is configured by these.

The heat radiating section 21 allows the heating and pressurizing tool 22.
Is heated to a predetermined temperature, and when necessary, the heating / pressurizing tool 22 can be lowered to the lower end opening of the suction nozzle 20 to apply pressure.

Then, first, the bonding stage 7 is moved to the substrate supply section, and the printed circuit board P is formed on the upper portion thereof.
To place. Then, the stage rail 17 is moved to and positioned at a bonding position which is a midway portion of the stage rail 17.

On the other hand, with respect to the tape extended from the carrier stocker 2, the punching portion 3 uses a mold to form an electronic component K.
Punch out. A large number of lead pins project at a narrow pitch on the punched electronic component K. This electronic component K is
It is supplied onto the component supply stage 5.

The bracket 11 stands by on the stage 5, and after confirming that the electronic component K is supplied onto the stage 5, the suction nozzle 20 descends and the electronic component K is sucked onto the lower end opening. To do.

Then, the suction nozzle 20 rises and the movement of the bracket 11 is started. Guide rail 9
While the bracket 11 is moving along, the component recognition camera 6 captures the image of the electronic component K sucked by the suction nozzle 20 and sends the image information to the control unit 18.

Here, the suction position and suction posture of the electronic component K stored in advance and the image information sent are compared and calculated to recognize the component, and the suction nozzle 20 is rotated by a required amount, and the normal operation is performed. Align with the mounting direction. and,
For example, it detects defective products such as missing lead pins.

The board position recognizing camera 13 attached to the bracket 11 captures the recognition mark image drawn on the board when the board position recognizing camera 13 moves above the printed board P, and sends the image information to the controller 18.

Here, the normal position of the printed circuit board K stored in advance and the image information sent are compared and calculated for recognition, and only the necessary amount of the bonding stage 7 is obtained.
Is slightly moved, and the stop position of the bracket 11 is adjusted.

Next, the suction nozzle 20 descends to mount the electronic component K on the printed circuit board P, and the heating / pressurizing tool 22 heated to a required temperature by the heat radiating portion 21 descends to drop the electronic component K. Pressurize the lead pin.

After this state is continued for a predetermined time, the heating / pressurizing tool 22 and the suction nozzle 20 are driven to rise. Eventually, the lead pins of the electronic component K are thermocompression-bonded to the circuit pattern of the printed board P to mount the electronic component K.

The board position recognizing camera 13 is provided on the bracket 11, and the bracket 11 is also provided with a heating and pressing body 23. That is, the camera 13 is within the range affected by the heat of the heating and pressing body 23.

As shown in FIG. 4, in the above device, 2
When two bonding heads are provided, the temperature inside the first bonding head A1 indicated by the solid line change and the temperature inside the second bonding head A2 indicated by the dotted line change are high.

On the other hand, room temperature B indicated by a two-dot chain line change
Although the temperature is low, the temperature inside the lens barrel of the substrate position recognizing camera 13 indicated by the alternate long and short dash line change C is
It is higher than room temperature under the influence of heat.

Therefore, the board position recognition camera 1 is used.
In No. 3, a slight optical axis shift occurs due to the heat effect of the heating and pressing body 23. In the present apparatus, the board position recognition camera 13 captures an image of the position correction recognition mark M provided in the vicinity of the component recognition camera 6, and sends the image information to the control unit 18.

In the control unit 18, the change amount of the relative position of the board position recognizing camera 13 and the component recognizing camera 6 with respect to the passage of time is calculated from the position of the currently detected position correcting recognition mark M. calculate.

After moving the bonding head 12 and the board position recognizing camera 13 onto the circuit pattern of the printed board P, the relative position of the board position recognizing camera 13 and the component recognizing camera 6 calculated previously is determined. A change amount, that is, a correction amount is added to the detected bonding position of the electronic component K to perform position correction between the electronic component K and the mounting position.

The change D in the broken line shown in FIG.
The average value of the displacement amount of the mounting position with respect to time when no correction is performed is shown. Recently, the lead pin pitch is 0.3.
Since it is in the range of up to 0.2 mm and tends to become narrower, it is required to further reduce the deviation amount.

Under the same preconditions, when the correction means as in the above-mentioned embodiment is adopted, the deviation amount is the one-dot chain line change E in the figure.
The maximum value shown by a and the minimum value shown by the two-dot chain line change Eb are obtained, and the average value shown by the solid line change E is obtained.

That is, by adopting the means of the present invention, the average value becomes approximately half of the conventional value, and it is possible to sufficiently cope with the pitch of the lead pins becoming narrower. Further, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the scope of the present invention.

[0041]

As described above, according to the present invention, the image pickup device is arranged within the range affected by heat, and even if the image pickup device is deviated from the optical axis, the electronic device having the lead pin with a narrow pitch is provided. There is an effect that the position of the component is corrected, the position of the circuit pattern formed on the printed circuit board can be adjusted with high accuracy, and the accuracy and reliability can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part of an electronic component mounting apparatus showing an embodiment of the present invention.

FIG. 2 is a front view of the essential parts of the electronic component mounting apparatus of the embodiment.

FIG. 3 is a perspective view of the electronic component mounting apparatus of the embodiment.

FIG. 4 is a diagram showing a temperature change with time in the electronic component mounting apparatus.

FIG. 5 is a diagram showing changes in the amount of deviation with time in the mounting device having the conventional structure and the mounting device of the present invention.

[Explanation of Codes] K ... Electronic component (TCP), P ... Printed circuit board, 14 ... Adsorption carrier, 23 ... Heating / pressurizing body, 13 ... First imaging body (board position recognition camera), 6 ... Second Image sensor (camera for component recognition).

Claims (2)

[Claims] 1. Adsorbing an electronic component supplied from a supply unit,
A suction carrier that is transported to and placed on a predetermined position on the printed circuit board, and a lead pin for the electronic component that is disposed in the vicinity of the suction carrier and that moves with the suction carrier and that is mounted on the predetermined position on the printed circuit board. A heat and pressure body for thermocompression bonding, and a printing device that is arranged in the vicinity of this heat and pressure body, moves with the suction conveyance body and the heat and pressure body, and recognizes the image of the alignment mark provided on the printed circuit board. Recognizing the first image pickup body that sends the alignment information of the board and the electronic component that is sucked and transported by the suction transporter,
A second image pickup body for sending the electronic component suction posture, quality judgment, and position alignment information, a position correction recognition mark provided in the vicinity of the second image pickup body, and the position correction recognition mark are described above. The change amount of the relative position with respect to the second image pickup object is calculated by taking in the first image pickup device, and the electronic component mounting position is corrected based on the calculated change amount of the relative position. An electronic component mounting apparatus comprising: a means for calculating an amount. 2. A heating / pressurizing body for mounting a lead pin of the electronic component on the printed circuit board by thermocompression bonding is provided in the vicinity of the sucking / conveying body for sucking / transporting the electronic component, and the range affected by the heat of the heating / pressurizing body. An electronic component mounting apparatus in which a first image pickup body for recognizing an image of a position alignment mark of a printed circuit board is provided, wherein the first image pickup body recognizes a separately provided position correction recognition mark, The second image pickup body recognizes the electronic component sucked and conveyed to the suction conveyance body, and the recognition image information of the first image pickup body and the second image pickup body is fetched, so that the time elapse of each image pickup body The amount of change in the relative position is calculated, and based on the calculated amount of change in the relative position, the correction amount of the electronic component mounting position is calculated, and the position of the electronic component and the mounting position of the electronic component are aligned. Electronic component mounting position characterized by correction Positive way.