JP3785887B2 - Electronic component mounting method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic component mounting method for mounting electronic components on a substrate.
[0002]
[Prior art]
In an electronic component mounting apparatus that mounts an electronic component on a substrate, the electronic component stored in the supply unit is picked up by a transfer head, transferred onto the substrate, and mounted at a predetermined mounting point. As a method for picking up electronic components, a method of vacuum suction using a suction nozzle is widely used. In general, the type and size of the suction nozzle varies depending on the electronic component to be sucked, and is exchanged and mounted according to the suction target. The mounting method is adopted.
[0003]
[Problems to be solved by the invention]
However, since the suction nozzle held by the elastic force is not completely fixed to the transfer head, it may drop off when an external force larger than the holding force by the elastic force is applied. For example, when picking up and picking up an electronic component stored in the tray, if the suction nozzle is lowered to a position where no electronic component is present and vacuum suction is performed, the suction nozzle sucks the tray itself. When the transfer head rises while the tray is sucked, there is a problem that the suction nozzle falls off the transfer head when the weight of the tray is larger than the holding force. Even in such a case, conventionally, this problem cannot be detected, and there is a problem in that the operation is shifted to the next operation while being dropped and other operation abnormalities are induced.
[0004]
Further, a filter for removing foreign matters such as dust sucked from the suction nozzle is inserted in a circuit from the suction nozzle to the vacuum suction source. Although it is necessary to perform maintenance such as replacing the filter before it becomes clogged, it has been difficult to estimate the maintenance inspection time because there is no appropriate method for detecting the clogged state.
[0005]
Therefore, an object of the present invention is to provide an electronic component mounting method that can reliably detect whether or not a suction nozzle is mounted and can estimate the maintenance and inspection time of a filter.
[0006]
[Means for Solving the Problems]
The electronic component mounting method according to claim 1, wherein the electronic component is vacuum-sucked by a suction nozzle that is detachably mounted on the mounting portion of the transfer head from the electronic component supply unit and picked up and mounted on the substrate. The vacuum level when the suction nozzle is mounted on the transfer head mounting part and the vacuum level when the suction nozzle is not mounted are stored in the data storage unit and detected by the vacuum sensor. By comparing the degree of vacuum with the level of the degree of vacuum stored in the data storage unit, it is determined whether or not the suction nozzle is mounted on the mounting unit , and the degree of vacuum is always detected in the mounting operation. By monitoring, it is detected that the suction nozzle has fallen off and is not attached, and a notification unit notifies that effect .
[0008]
According to the present invention, the degree of vacuum detected by the vacuum sensor is the degree of vacuum stored in the data storage unit.
By comparing with the level, it is possible to determine whether or not the suction nozzle is mounted on the mounting portion of the transfer head by a simple method.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. 1 is a perspective view of an electronic component mounting apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a transfer head of the electronic component mounting apparatus, and FIG. 3 shows a configuration of a control system of the electronic component mounting apparatus. FIG. 4 is a graph showing vacuum degree measurement data of the electronic component mounting apparatus.
[0010]
First, an electronic component mounting apparatus will be described with reference to FIG. In FIG. 1, a transport path 2 is arranged in the X direction at the center of a base 1. The transport path 2 is a positioning unit that transports and positions the substrate 3. On both sides of the transport path 2, electronic component supply units 4 are arranged. The supply unit 4 supplies a tape feeder 5 that supplies the taped electronic components and a tray feeder that supplies the electronic components P stored in the tray 7. 6.
[0011]
A transfer head 9 for electronic parts is mounted on the X-axis table 8. The transfer head 9 is a multiple type and includes a plurality of suction nozzles 11. The X-axis table 8 is installed on a pair of parallel Y-axis tables 10. By driving the X-axis table 8 and the Y-axis table 10, the transfer head 9 moves horizontally, and from the pickup position 5 a of the tape feeder 5 and a predetermined tray 7 of the tray feeder by the suction nozzle 11 mounted at the lower end. The electronic component P is picked up and transferred to the substrate 3 on the transport path 2.
[0012]
A line camera 15 is disposed on the movement path of the transfer head 9 between the conveyance path 2 and the supply unit 4. While moving the transfer head 9 holding the electronic component horizontally above the line camera 15, the electronic component is recognized by imaging the electronic component with the line camera 15.
[0013]
Next, the transfer head 9 will be described with reference to FIG. FIG. 2 shows a single transfer head 9A that constitutes the transfer head 9, and the transfer head 9A includes a suction nozzle 11 that sucks an electronic component. The suction nozzle 11 is detachably mounted on a mounting portion provided on the lower surface of the transfer head 9A by a holding mechanism using a holding force of an elastic body such as a spring. In a state where the suction nozzle 11 is mounted on the transfer head 9, the suction hole 11a of the suction nozzle 11 and the suction hole 9a provided in the transfer head 9A are in communication with each other.
[0014]
On the side surface of the transfer head 9A, a conduit 9b communicating with the suction hole 9a is provided, and the conduit 9b is further connected to the switching valve 12. The switching valve 12 is connected to an air source 13 and a vacuum suction source 14, and air is discharged from the suction nozzle 11 by driving the air source 13 with the switching valve 12 switched to the air source 13 side. The Further, by performing vacuum suction with the switching valve 12 switched to the vacuum suction source 14 side, vacuum suction can be performed from the suction hole 11b of the suction nozzle 11, and the electronic component can be sucked into the suction hole 11b.
[0015]
A filter 17 made of a porous material is inserted in the middle of the conduit 9b, that is, in a circuit extending from the attachment portion of the suction nozzle 11 to the vacuum suction source 14. The filter 17 has a role of capturing minute foreign matters such as dust contained in the air flowing in the pipe line 9b. Further, a vacuum sensor 16 (vacuum degree measuring means) is connected from the filter 17 to the conduit 9b on the vacuum suction source 14 side. The vacuum sensor 16 measures the degree of vacuum in the pipe line 9b. The measured vacuum degree data is transmitted to the vacuum degree detector (FIG. 3). Even when vacuum suction is performed with the vacuum suction conditions in the vacuum suction source 14 being the same, the numerical value of the degree of vacuum detected varies depending on the state of the vacuum suction circuit such as the suction nozzle 11 and the conduits 9a and 9b. .
[0016]
Next, a control system of the electronic component mounting apparatus will be described with reference to FIG. In FIG. 3, a control unit 20 is a CPU, and controls the operation of the entire electronic component mounting apparatus. The program storage unit 21 stores programs necessary for various operations such as a sequence program for mounting operations. The data storage unit 22 stores various data such as mounting data and reference data for determination based on a vacuum degree measurement value described later. Note that a vacuum sensor 16 having a data storage function may be used, and the reference data for determination may be stored in the vacuum sensor 16 itself.
[0017]
The mechanism control unit 24 performs drive control of each motor that drives the XY table mechanism and the transfer head 9. The recognition processing unit 25 performs image processing of the image data of the electronic component acquired by the line camera 15, thereby identifying and position recognition of the electronic component held by the transfer head 9. The operation / input unit 26 is an operation button or a keyboard provided on the operation panel. The vacuum degree detection unit 27 receives a signal from the vacuum sensor 16 and detects the vacuum degree. The detected vacuum degree data is sent to the determination unit 28, and the determination unit 28 determines whether or not the suction head 11 is attached to the transfer head 9A and the filter maintenance inspection time based on the vacuum degree data. The notification unit 29 notifies the determination result of the determination unit 28.
[0018]
Next, reference data used for determination based on the vacuum degree measurement value will be described with reference to FIG. FIG. 4A compares the degree of vacuum in a state where the suction nozzle 11 is mounted on the mounting portion of the transfer head 9A and a state where the suction nozzle 11 is not mounted. In the unmounted state, the vacuum suction circuit is in a state where the suction hole 9a in the transfer head 9A communicates with the outside as it is. The degree of vacuum is low level a1.
[0019]
On the other hand, when the suction nozzle 11 is mounted on the mounting portion of the transfer head 9A, the vacuum suction circuit is in communication with the outside only through the suction hole 11b of the suction nozzle 11, so that the amount of air sucked Therefore, the level of the degree of vacuum by the vacuum sensor 16 is a level a2 higher than the above-described level a1. Furthermore, when the suction nozzle 11 is sucking an electronic component, the suction hole 11b is almost blocked, and therefore a higher vacuum level a3 is shown. Thus, the level of the degree of vacuum detected by the vacuum sensor 16 varies greatly depending on the state of the vacuum suction circuit.
[0020]
In other words, it is possible to estimate how the vacuum suction circuit communicates with the outside by detecting the degree of vacuum in the vacuum suction circuit. That is, the degree of vacuum detected by the vacuum sensor 16 is constantly monitored by the determination unit 28 and compared with the above-described degree of vacuum levels a1, a2, and a3, so that the suction nozzle 11 is mounted on the transfer head 9A. It can be determined whether or not there is an abnormality or the suction nozzle 11 has fallen off. These vacuum levels a1, a2, and a3 are stored in the data storage unit 22, and when the determination unit 28 performs the above-described determination, the determination is performed based on these data.
[0021]
FIG. 4B shows a change in the degree of vacuum in the vacuum suction circuit due to a change with time of the filter 15. That is, the filter 15 is gradually clogged with the passage of time of use, and as a result, the degree of vacuum in the conduit 9b on the vacuum suction source 14 side with respect to the filter 15 tends to gradually increase. Therefore, the clogged state of the filter 15 can be estimated from the detection result of the vacuum sensor 16 as described above.
[0022]
That is, when the detected value of the vacuum sensor 16 rises from the vacuum level b0 in the initial state and reaches a predetermined vacuum level bL, a notification is made that it is the maintenance inspection time of the filter 15. Thereby, it is possible to accurately detect the clogged state of the filter 15 that is difficult to discriminate by a normal method such as visual observation. These data are similarly stored in the data storage unit 23, and the determination unit 28 determines whether or not it is a maintenance inspection time based on these data.
[0023]
The electronic component mounting apparatus is configured as described above, and the operation will be described below. When the mounting operation is started, the transfer head 9 picks up an electronic component from the supply unit 4, moves on the line camera 15, recognizes the component, and then mounts the held electronic component on the substrate. To do.
[0024]
In this mounting operation, when the electronic component P is picked up from the tray 7, for some reason, the suction nozzle 11 descends to a position where the electronic component P does not exist on the tray 7 and may directly suck the tray 7 itself. . In this case, since there is no means for discriminating whether the electronic component is sucked or the tray 7 is sucked, the tray 7 may be lifted while the transfer head 9A is lifted. At this time, if the weight of the tray 7 is larger than the holding force for the transfer head 9A to hold the suction nozzle 11, an abnormality may occur in which the suction nozzle 11 falls off the transfer head 9A.
[0025]
Even in such a case, as described above, the degree of vacuum in the vacuum suction circuit is always detected by the vacuum sensor 16 and is monitored by the determination unit 28, so that the suction nozzle 11 can be quickly removed and not mounted. Detected. Thereby, the fact is notified and the operation of the mounting apparatus is stopped. Therefore, there is no new abnormality induction by continuing the operation in the abnormal state in which the suction nozzle 11 is dropped and not attached, and an accident such as damage to the apparatus can be prevented.
[0026]
Further, while the mounting operation is continued for a long time, the filter 17 inserted in the pipe line is clogged by the foreign matter sucked from the suction nozzle 11. At this time, by similarly monitoring the degree of vacuum in the pipe line, when the degree of vacuum corresponding to a predetermined clogging state is reached, the filter 17 is automatically informed that it is time for maintenance and inspection. Is called. Thereby, normal vacuum suction can always be performed without causing suction failure due to filter clogging.
[0027]
【The invention's effect】
According to the present invention, by comparing the degree of vacuum detected by the vacuum sensor with the level of degree of vacuum stored in the data storage unit, whether the suction nozzle is attached to the mounting part of the transfer head by a simple method . Whether it can be determined .
[Brief description of the drawings]
FIG. 1 is a perspective view of an electronic component mounting apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a transfer head of the electronic component mounting apparatus according to an embodiment of the present invention. FIG. 4 is a block diagram showing a configuration of a control system of the electronic component mounting apparatus according to the embodiment. FIG. 4 is a graph showing vacuum degree measurement data of the electronic component mounting apparatus according to the embodiment of the present invention.
3 Substrate 4 Supply unit 7 Tray 9 Transfer head 11 Suction nozzle 14 Vacuum suction source 16 Vacuum sensor 17 Filter

Claims (1)

An electronic component mounting method in which an electronic component is vacuum-sucked by a suction nozzle that is detachably mounted on a transfer head mounting unit from an electronic component supply unit and picked up and mounted on a substrate. The vacuum level when the suction nozzle is mounted and the vacuum level when the suction nozzle is not mounted are stored in the data storage unit, and the vacuum level detected by the vacuum sensor is stored in the data storage unit. The vacuum level is compared to determine whether or not the suction nozzle is mounted on the mounting part. By constantly detecting and monitoring the vacuum level in the mounting operation, the suction nozzle is dropped. An electronic component mounting method, characterized in that an unmounted state is detected and a notification unit notifies the fact.

Images