JP3133588B2 - Electronic component automatic mounting device and electronic component mounting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic electronic component mounting apparatus and an electronic component mounting method for taking out an electronic component from a component supply section by a take-out nozzle provided in a transfer head and mounting the electronic component on a printed circuit board.

[0002]

2. Description of the Related Art This type of automatic electronic component mounting apparatus is now open.
This is disclosed in Japanese Patent Application Laid-Open No. 0-121671, and it is determined that the posture of the electronic component sucked by the suction means is correct when the light beam from the light emitting element is detected by the light receiving element, and the component thickness changes depending on the component type. In this case, the height of the light emitting element and the light receiving element is changed by rotating the drive lever in accordance with the information on the thickness of the component, so that the correct orientation or shape of the component is determined.

[0003]

However, in the above-mentioned prior art, when the surface of the electronic component that is not to be attracted is attracted and is completely standing, the light from the light emitting element is blocked by the component. Can be detected, but since the detection is performed in a state where the take-out nozzle, which is a normal suction means, is stopped at a predetermined position, as shown in FIG.
Is held in the take-out nozzle 101 in an oblique state, the normally sucked part 100 is indicated by a two-dot chain line, and the light beam is directed at the point A in FIG. In such a case, the light is not shielded by the electronic component 100, so that it is determined that the electronic component 100 is sucked in a normal posture. In order to solve this drawback, a technology has been developed that enables the line sensor to detect the lower end position of the part being moved by the transport head at a plurality of positions to more accurately determine the part attitude. Conceivable.

However, in such a case, it takes time to calculate the lower end position from the output of the line sensor. After calculating the lower end position, the output of the line sensor at the next head movement position is read and the lower end position is read. Since the calculation is performed, when the moving speed of the transport head is high, the detection interval of the lower end position becomes too large, and there is a disadvantage that the posture or the shape abnormality cannot be accurately determined.

Accordingly, an object of the present invention is to make it possible to reliably determine an abnormal posture or shape of a pick-up nozzle for an electronic component.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to an automatic electronic component mounting apparatus for removing an electronic component from a component supply unit by a removal nozzle provided on the transport head and mounting the component on a printed circuit board. Detecting means for detecting the lower end position of the electronic component held by the take-out nozzle at predetermined time intervals based on the output of the line sensor, and the take-out nozzle and the line sensor according to the type of electronic component held by the take-out nozzle Control means for controlling the relative speed of the discharge head, and a plurality of lower end positions output by the detection means during the relative movement of the transfer head and the line sensor at a speed controlled by the control means. Determining means for determining whether the posture or shape of the electronic component is abnormal.

According to the present invention, there is provided an automatic electronic component mounting apparatus for holding an electronic component by a plurality of transport heads provided on a periphery of the rotary table, transporting the electronic component by intermittent rotation of the rotary table, and mounting the electronic component on a printed circuit board. Detecting means for detecting the lower end position of the component at predetermined time intervals based on the output of a line sensor provided at a predetermined stop station; and intermittent operation of the rotary table according to the size of the electronic component in the head moving direction. Control means for controlling the rotation speed, and the attitude or shape of the component based on a plurality of lower end positions output by the detection means during the movement of the head before and after the stop of the intermittent rotation at a speed controlled by the control means. It is provided with a judging means for judging whether it is abnormal.

According to the present invention, there is provided a method of mounting an electronic component on a printed circuit board, wherein the electronic component is taken out from a component supply unit by a take-out nozzle provided on the transfer head. A speed determining step of determining a relative moving speed with respect to a line sensor for detecting a lower end position in accordance with a component type; and a predetermined time during relative movement of the transport head with respect to the line sensor at the speed determined in the speed determining step. A lower end position detecting step of detecting a plurality of lower end positions of the electronic component held by the nozzle by an output of the line sensor for each interval, and a posture of the component based on the plurality of lower end positions detected in the lower end position detecting step; It has a judging step of judging a shape abnormality.

[0009]

According to the first aspect of the present invention, the determination means is based on a plurality of lower end positions output by the detection means at predetermined time intervals during the relative movement at the speed controlled by the control means of the transport head and the line sensor. Determines whether the posture or shape of the electronic component held by the take-out nozzle is abnormal.

According to the second aspect of the present invention, the size of the electronic component in the mounting head moving direction controlled by the mounting head control means by the output of the line sensor provided at the predetermined stop station of the rotary table is controlled. During the movement before and after the stop of the intermittent rotation at the corresponding speed, the detecting means detects a plurality of lower end positions of the electronic component at predetermined time intervals, and based on the lower end positions, the judging means determines an abnormal posture or shape of the electronic component. Judge.

According to a third aspect of the present invention, the lower end position detecting step in which the transport head is moving with respect to the line sensor at the relative speed determined according to the component type in the speed determining step is performed at predetermined time intervals. A plurality of lower end positions of the electronic component held by the nozzle are detected based on the output of the line sensor, and an abnormality in the posture or the shape of the component is determined based on the plurality of lower end positions in the determining step.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 2 and 3, reference numeral 1 denotes a Y table which moves in the Y direction by rotation of a Y-axis motor 2, and 3 denotes a movement in the X direction on the Y table 1 by rotation of an X-axis motor 4. As a result, the printed circuit board 6 on which the chip-shaped electronic components 5 (hereinafter, referred to as chip components or components) are mounted is fixedly mounted on fixing means (not shown).

Reference numeral 7 denotes a supply table on which a number of component supply devices 8 for supplying the chip components 5 are provided. Reference numeral 9 denotes a supply table drive motor, which rotates the ball screw 10 so that the supply table 7 is guided by the linear guide 12 via a nut 11 fitted with the ball screw 10 and fixed to the supply table 7, and X Move in the direction. Reference numeral 13 denotes a rotary table which rotates intermittently. At the outer edge of the table 13, mounting heads 15 as transfer heads having six suction nozzles 14 as take-out nozzles are arranged at equal intervals in accordance with an intermittent pitch. I have.

The stop position of the mounting head 15 where the suction nozzle 14 sucks and picks up the component 5 from the supply device 8 is a suction station, where the suction nozzle 14 sucks the component 5. Reference numeral 16 denotes a component recognition device for recognizing a positional shift of the component 5 to be sucked by the suction nozzle 14 by using a camera to image the lower surface of the component 5 within a predetermined visual field range and recognizing and processing the captured screen. The station where the moving mounting head 15 stops on the device 16 is the recognition station.

The position at which the mounting head 15 next to the recognition station stops is the angle correction station, and mounting data (not shown) in which an angle amount for correcting the angular position deviation of the chip component 5 based on the recognition result of the recognition device 16 is predetermined. Head rotation device 1 by an angle amount that is added to the angle amount shown in FIG.
7 rotates the mounting head 15 in the θ direction. The next stop position after the angle correction station is the mounting station, and the component 5 to be suctioned by the suction nozzle 14 of the station is mounted on the substrate 6.

Numeral 20 denotes an elevating rod which moves up and down, engages with an oscillating lever 21 of the component supply device 8 and oscillates to fit a component storage tape (not shown) in which the chip components 5 are sealed at a predetermined interval. The chip component 5 is supplied to the component suction position of the suction nozzle 14 by intermittent feeding. Reference numeral 22 denotes a tape reel for winding the component storage tape (not shown). The next station following the suction station is provided with a line sensor 27 for detecting the attitude of the chip component 5 that is suctioned and held by the suction nozzle 14. As shown in FIG. 4, the line sensor 27 emits a light beam that travels straight in the horizontal direction, and a light receiving device in which a number of CCD elements are arranged on a straight line in the vertical direction so as to be able to receive the light beam. And a vessel 29. The light projector may condense the light of the LED with a lens and emit a parallel light beam having a certain width in the vertical direction and a very narrow width in the horizontal direction, or using a laser. You may do so. For example, a CCD device in which about 1,000 CCD elements are arranged in a vertical width of about 10 mm can be realized. Since each of the CCD elements can detect ON / OFF of the light reception, the output of the CCD element can detect the part light-shielded by the component 5 or the suction nozzle 14 as height position data.

The line sensor 27 is a rotary table 1
In FIG. 2 due to the rotation of 3, the suction nozzle 14 is fixed and attached so that the light beam emitted from the light projector 28 hits the approximate center of the suction nozzle 14 at the stop position. next,
A control block of the electronic component automatic mounting apparatus according to the present embodiment will be described with reference to FIG.

Reference numeral 31 denotes a CPU, which controls various operations relating to the mounting of the chip component 5 in accordance with a program stored in the ROM 33 based on various data stored in the RAM 32 and information on sensors such as the line sensor 27. . The line sensor 31 is connected to the CPU 31 via an interface 34. The index motor 35, which is one of the control objects of the CPU 31, is connected to the CPU 31 via the interface 34 and the drive circuit 36.
It is connected to the.

The output of the line sensor 27 is output for each CCD element. The lower end peak value is the lower end position where the height position of the boundary from the lowermost light-shielded portion to the light-transmitted portion is the lower end position. Is calculated by the CPU 31. RAM
32 is provided with a capture memory 38 as a lower end position storage means during movement and a hold memory 39 as a lowermost position storage means, and the capture memory 38 is calculated from the output of the line sensor 27 at regular time intervals. That is, the lower end height position of the component 5 for each predetermined moving distance of the suction nozzle 14 is read, and the hold memory 39 stores a lower end position which is larger than the value of the loading memory 38, that is, the lower end position of the lower end.

The interface 34 is further connected to a cam positioner 41.
Reference numeral 1 denotes a rotation angle of an input shaft of an index unit (not shown) that rotates the rotary table 13 intermittently. The rotation angle origin is set to 0 degree, and a rotation angle position during one rotation of 360 degrees is detected. Outputs the angle. The rotary shaft of the rotary table 13 is connected to the output shaft of the index unit, and is mounted on the suction station and the mounting station by a cam (not shown) which rotates in synchronization with the input shaft of the index unit. Vertical movement of head 15 and lifting rod 2
Since the vertical movement of 0 is driven, the component suction and component mounting operations are performed in synchronization with one intermittent rotation of the rotary table 13. The period of one rotation of the input shaft of the index unit, that is, the period of one intermittent rotation of the rotary table 13 is referred to as one cycle. The shorter this cycle time (hereinafter, referred to as the cycle time), the higher the speed at which components can be mounted, The speed of the index motor 35 is adjusted by the CPU 31 so that the cycle time determined for each part 5 is achieved.
Is controlled.

The RAM 32 further stores component data for each component type as shown in FIG. 6, and stores component thickness data for comparison with the height position, which is the lowermost position, stored in the hold memory 39. Further, data of a component thickness allowable value, which is regarded as an allowable value at the time of the comparison, and an attitude detection cycle time which specifies the rotation speed of the index motor 35 for the attitude detection by the time required for intermittent rotation are stored.

The detection start angle indicating the timing at which the CPU 31 starts reading for posture detection and the detection end angle indicating the detection end timing are stored in the ROM 33 as fixed values. The detection start angle is a timing at which the detection is started when the angle detected by the cam positioner 41 is the angle every one intermittent rotation of the rotary table 13, and the detection end angle is also the same. The moving position of the head 15 at this angle is always a fixed position,
The angle position is set such that the largest size of the chip component 5 sucked by the component 4 in the head moving direction can be detected.

However, the speed of the intermittent rotation of the rotary table 13 during the one intermittent rotation (hereinafter referred to as one cycle) from the highest speed to the stop is shown by the angle indicated by the cam positioner 41 on the horizontal axis as shown in FIG. Draw a simple curve. On the other hand, C
In order to detect the lower end position, the PU 31 reads the output of the line sensor 27 as shown in the flowchart of FIG. 5 and takes a certain time to perform processing operations such as calculation of the lower end position of the chip component 5 and then perform the next operation. Since the output of the line sensor 27 is read and the same processing is performed, the lower end position at which the output can be read is at each interval at which the head 15 has moved during the processing time, and when the head speed increases, two vertical points shown in FIG. Only the lower end position that is farther than the lowermost end position, such as the chain line, can be detected, so the maximum value of the detectable speed must be set.

However, if the maximum value is set to "VM" in the speed curve shown in FIG. 7, only the fixed angular position before and after the intermittent rotation stops can be used for detecting the lower end position. Further, in the state where the chip component 5 is sucked by the suction nozzle 14 according to the size of the chip component 5, as shown in FIG.
Is moved to the position of the optical axis of the line sensor 27, the chip component 5 larger in the transport direction than it
The tip may move to the optical axis at the angle position of
In the case of the component 5 whose tip reaches the optical axis at an angle of θ2, the moving speed is too high to make an accurate determination by the CPU 31, so that the rotary table 1 can be detected at a certain interval or less.
It is necessary to reduce the speed of No. 3 and the posture detection cycle time data is stored in the component data so as to form a curve as shown by the two-dot chain line in FIG. In this manner, data of the posture detection cycle time is stored for each component type according to the size of the chip component 5 in the head transport direction so that the maximum speed has a speed curve that can be detected in the range of “VM”. . In FIGS. 7 and 9, for convenience of explanation, the cycle time is selected by setting the position of the tip to θ1 or θ2, but a margin considering the deviation of the suction is given by the angular position on the left side of FIG. It is necessary to set the posture detection cycle time to be in the range of “VM”. This can be said even when the intermittent rotation starts. Since the speed gradually increases, if the size of the component 5 in the horizontal direction is large, the speed is increased before the end is detected, and the posture and the shape are abnormal. The posture detection cycle time is determined in the same manner as in the case of stopping, because it is not accurate to make the determination. In this embodiment, since the speed curve is substantially symmetrical and the conditions before the stop and the conditions at the start are the same, one posture detection cycle time is set.

Further, as shown in FIG. 10, in the case of the chip component 5 having the leads 44, it is necessary to detect the bending of the leads 44, so that the lower end position is smaller than the width "T" of the leads 44 in the lateral direction. There is a demand to perform the detection. In this case, the posture detection cycle time must be determined not only by the above-mentioned speed “VM” but also by the maximum speed for detecting the lead 44.

The operation of the above configuration will be described below. First, when the operation unit (not shown) is operated and the automatic operation of the electronic component automatic mounting apparatus is started, the supply table is stored in the RAM 32 in accordance with the data in which the data on the components 5 to be mounted in the mounting order (not shown) is stored. The component supply device 8 for the chip component 5 to be moved and supplied is moved to the suction stage.
The chip component 5 is taken out by stopping at the suction position of the suction nozzle 14 of the mounting head 15 of the application and lowering the nozzle 14.

Next, the rotation of the index motor 35 causes the rotary table 13 to rotate intermittently via an index unit (not shown), and the head 15 moves to the next stage.
The line sensor 27 is moved to the station where the line sensor 27 is provided. This intermittent rotation speed is rotated at a speed corresponding to the posture detection cycle time stored in the component data of FIG.

When it is time to start detection shortly before the movement of the rotary table 13 stops, the cam positioner 41 detects the angular position, and the CPU 31 returns to FIG.
The operation shown in the flowchart of FIG. That is, the light beam of the light projector 28 of the line sensor 27 is always emitted and the light of the light receiver 2 is always emitted.
Assuming that the light is received at 9 and its output is always performed, at this start timing, first, the capture memory 3
8 and the hold memory 39 are cleared, and the CPU 31 calculates the lowermost peak value as the lowermost peak value based on the output of the line sensor 27, and stores the value in the memory 38. The origin is suction nozzle 1
4 is set to be higher than the height position of the lower end face, and is set to be positive below.

The CPU 31 stores this value in the hold memory 39
Is stored in the hold memory 39. Since the position is initially the position where the component 5 is not present,
It remains "0". While this process is being performed, the nozzle 14 is moving, and it is not the detection end timing, so the CPU 31 performs the same process again. When the CPU 31 reads this output when the position indicated by the leftmost vertical dotted line of FIG. 8 is the position of the light beam of the light projector 28 of the line sensor 27, the lower end position indicated by the dotted circle in FIG. 8 is calculated. , The value of this position is stored in the capture memory 38,
The fetched memory 38 is compared with the value of the hold memory 39.
Is large, the value is read into the hold memory 39.

Next, during this processing, the nozzle 14 moves, and at the time of reading by the next CPU 31, two nozzles from the left in FIG.
The output of the third dotted line sensor 27 is read by the CPU 31. Since this value is larger than the value of the hold memory 39, the value of the hold memory 39 is updated. Next, at the next reading position, since the lower end position becomes higher and the value becomes smaller, the value in the hold memory 39 is held as it is.

In this way, the output of the line sensor 27 is read at the position of each vertical dotted line in FIG. 8, and the cam positioner 41 detects the angular position of the detection end timing which is started after the intermittent rotation is stopped. Then, the CPU 31 stops reading, and the value stored in the hold memory 39 and RA
The component thickness of the component data of the component type to be compared stored in M32 is compared with the value added to the data of the nozzle level at the lower end position of the suction nozzle 14, and the difference is not within the component pressure allowable value, and the hold memory Since the value of 39 is larger, it is determined that the suction is abnormal (abnormal posture), and the following abnormal process control is performed.

The interval between the dotted lines gradually narrows because the moving speed of the nozzle 14 becomes slow. next,
As an abnormal process, the suction nozzle 14 is stopped in a subsequent stop state.
The chip component 5 is discharged at a predetermined discharge station without performing any work relating to component mounting even when stopped at the station, and without mounting the component at the mounting station.

Next, when the chip component 5 is normally sucked, the component 5 is provided with the line sensor 27 by moving the mounting head 15 at a speed corresponding to the attitude detection cycle time in the component data. When the position of the line sensor 27 is reached, the height level of the lower end surface of the component 5 is calculated each time the CPU 31 reads the output of the line sensor 27 and fetched into the fetch memory 38 as described above.
9 stores the lowermost position. Even if the chip component 5 is a component 5 having a large size in the horizontal direction, the posture detection cycle time is set to be large according to this.
At the position where the component 5 is shielded by the light beam of the line sensor 27, the lower end position is detected at intervals at which the posture can be determined.

Next, when the suction is performed normally, the value of the acquisition memory 38 is substantially constant, and the CPU 31 determines whether or not the component posture is abnormal after the detection end timing. Compared with the lower end position based on the data nozzle data and the component thickness data, it is within the component allowable value, so it is determined to be normal and the operation of the following normal processing is controlled.

Then, at the recognition station, the recognition device 16
The head 15 is rotated by the head rotation device 17 for swinging the chip component 5 based on the recognition result, and the XY table 3 is set at the mounting station.
The chip component 5 is mounted on the printed circuit board 6 positioned by the movement of. At this time, since the lower end position which is the height position of the lower end of the component 5 is detected, the descending distance of the suction nozzle is adjusted according to the lower end position, and the component 5 is mounted on the printed circuit board 6 with an appropriate pressure. Is done.

Next, when the chip component 5 with the leads 44 is conveyed, the size in the conveying direction and the size of the leads 4 are determined.
Rotary table 1 with cycle time in width 4
When the lead 3 is rotated and the lead is bent, an abnormality is detected from the fact that the lower end position is large, and the component 5 is discharged at a predetermined discharge station. In this way, every time the component 5 moves to the stop station of the line sensor 27, the abnormality of the attitude of the component 5 is determined, and an appropriate action is taken.

In this embodiment, the function shown in FIG. 5 is executed by only one CPU, but the function shown in FIG.
U, provided as a processing unit composed of a capture memory and a hold memory, and a CP of the electronic component automatic mounting apparatus.
U is connected via an interface and the other is connected to a line sensor. A signal of a detection start timing and a detection end timing is given from the CPU of the mounting device, and the contents of the hold memory after the detection is completed are stored in C of the mounting device.
The PU may read the information to determine whether it is normal or abnormal as described above.

Further, in this embodiment, even when the intermittent rotation is stopped, C
Although the detection operation of the line sensor 27 by the PU 31 has been performed, the processing operation for detection by the CPU 31 during this period need not be performed since the same lower end position is actually updated. The detection processing operation may be continued by rotating itself. In this embodiment, the line sensor 27 is provided at the stop station of the rotary table to detect the lower end position of the moving part 5 before and after the stop, but the line sensor 27 is provided between the stations. May be provided to detect the moving part 5, or the line sensor may be moved in the horizontal direction during the stop of the stop station to relatively move the detection position. The moving path of the head of the mounting device is not a rotary table type electronic component automatic mounting device, but a mounting head that is mounted on an XY table and moves to mount the electronic component at a predetermined position on a printed circuit board from a component supply unit. May be provided in the middle of the process.

Although the component data stored in the RAM 32 stores the component thickness and the nozzle level data and adds the lower end position thereof, the data of the lower end position may be stored directly.

[0040]

As described above, the present invention can be applied to a case in which an electronic component is obliquely attracted to a take-out nozzle, or a case in which the shape of a component with a lead is abnormal such as a bent part of the lead-out nozzle. The lower end position is detected by moving the speed relative to the line sensor in accordance with the type of the component, so that it is possible to reliably determine abnormalities in the posture and minimize a decrease in the moving speed. .

When the rotary table is intermittently rotated to detect an electronic component held by a head provided on the peripheral edge of the rotary table, the intermittent rotation speed should be set in accordance with the size of the component in the head transport direction. Accordingly, abnormalities in the posture or shape of the electronic component can be reliably detected, and a decrease in the intermittent rotation speed can be minimized.

[Brief description of the drawings]

FIG. 1 is a control block diagram of an electronic component automatic mounting apparatus to which the present invention is applied.

FIG. 2 is a plan view of the electronic component automatic mounting apparatus.

FIG. 3 is a side view of the electronic component automatic mounting apparatus.

FIG. 4 is a side view showing a line sensor.

FIG. 5 is a diagram showing a flowchart.

FIG. 6 is a diagram showing component data.

FIG. 7 is a diagram showing a speed curve of intermittent rotation of the mounting head.

FIG. 8 is a side view showing a state in which a chip component is sucked by a suction nozzle.

FIG. 9 is a side view showing a state where the chip component is sucked by the suction nozzle.

FIG. 10 is a side view showing a state in which a chip component with a lead is sucked.

FIG. 11 is a side view showing a state in which a chip component is sucked by a suction nozzle according to the related art.

[Explanation of symbols]

 Reference Signs List 5 Chip-shaped electronic component (electronic component) 6 Printed circuit board 14 Suction nozzle (extraction nozzle) 15 Mounting head (transport head) 27 Line sensor 31 CPU 32 RAM (storage means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-289692 (JP, A) JP-A-62-193199 (JP, A) JP-A-62-263405 (JP, A) 252328 (JP, A) JP-A-6-174449 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05K 13/02 H05K 13/04 H05K 13/08

Claims (3)

(57) [Claims] An electronic component automatic mounting apparatus for taking out an electronic component from a component supply unit by a take-out nozzle provided on a transfer head and mounting the same on a printed circuit board. Detection means for detecting the lower end position of the component at predetermined time intervals by the output of the line sensor, and control means for controlling the relative speed between the extraction nozzle and the line sensor according to the type of electronic component held by the extraction nozzle, During the relative movement of the transfer head and the line sensor at the speed controlled by the control unit, the detection unit determines whether the posture or shape of the electronic component held by the ejection nozzle is abnormal based on a plurality of lower end positions. An electronic component automatic mounting apparatus, comprising: 2. An electronic component automatic mounting apparatus in which electronic components are held by a plurality of transport heads provided on a peripheral edge of a rotary table, transported by intermittent rotation of the rotary table, and mounted on a printed circuit board, a predetermined stop of the rotary table. Detecting means for detecting the lower end position of the component at predetermined time intervals based on the output of a line sensor provided at a station; and intermittent rotation speed of the rotary table in accordance with the size of the electronic component in the head moving direction. Controlling means for controlling, whether or not the posture or shape of the component is abnormal based on a plurality of lower end positions output by the detecting means during movement before and after stopping the intermittent rotation of the head at a speed controlled by the control means; An electronic component automatic mounting apparatus, comprising: a determination unit for determining whether the electronic component is mounted. 3. A method of mounting an electronic component, wherein the electronic component is taken out of a component supply unit by a take-out nozzle provided on a transfer head and mounted on a printed circuit board, wherein a lower end position of the electronic component held by the transfer head and the nozzle is determined. A speed determination step of determining a relative movement speed with respect to the line sensor for detection in accordance with a component type; and a predetermined time interval during the relative movement of the transport head with respect to the line sensor at the speed determined in the speed determination step. A lower end position detecting step of detecting a plurality of lower end positions of the electronic component held by the nozzle based on an output of the line sensor, and a posture or shape abnormality of the component based on the plurality of lower end positions detected in the lower end position detecting step A method of mounting an electronic component, comprising: