CN101233800B - Electronic component mounter and mounting method - Google Patents

Abstract

An object of the present invention is to provide a method by which the height of an electronic component picked up and held by a suction nozzle can be detected with high precision and high efficiency. The method is a component height measurement method applied to a mounter (100) equipped with a delivery head (8) with a component suction-holding nozzle (21) for delivering and mounting the part P on a board (3), the method comprising: lowering the part P within the high precision range of a first row of sensors (13) for measuring the height of the part P; and using the first row The sensor (13) measures the height of the part P.

Description

Electronic component mounter and mounting method

technical field

The present invention relates to a method for measuring the height (thickness) of a part that is picked up by suction of a mounter suction nozzle and mounted on a member such as a board or the like.

Background technique

The height of the electronic component to be mounted is one of the important parameters of the mounter. More specifically, if the actual height of the electronic part held by the transfer head used to mount the electronic part is different from the value assigned to the electronic part and stored to control the mounter, then the electronic part is mounted When it comes to boards, all sorts of problems can happen. For example, where the actual height of the electronic component is smaller than the stored data, the electronic component is released before it reaches the board, so it may not arrive at the correct position on the board. Conversely, if the actual height of the electronic part is larger than the stored data, the electronic part is pressed against the board too strongly, possibly causing damage to the board, the electronic part, or the suction nozzle.

Conventionally, in order to input the height data of the electronic parts into the mounter, the height data of the electronic parts is obtained from the manufacturer of the electronic parts and inputted manually, or from a tape or the like for holding the electronic parts. The electronic parts are taken out and measured using calipers or the like, and the measured values are entered manually.

However, the height of the electronic components may vary depending on the manufacturer or manufacturing lot, and even if the performance of the electronic components does not change. For example, when the currently used electronic components are out of stock while the order-to-delivery time (from receipt of the board production order until board shipment) is shortened, there is no choice but to use another manufacturer's parts instead. In this case, the data for the replacement part must be entered manually even though the performance of the part has not changed. Not only is this data entry very cumbersome, it also leads to measurement errors or human error where the height of a substitute part is measured and the data for the part is entered manually, resulting in a discrepancy between the actual height of the part and the entered data.

Therefore, in order to avoid measurement errors and human errors and to ensure an exact match between the actual height of the electronic components and the data stored in the mounter, a patent application for a mounter as shown in Figure 1, which includes a detector , for detecting the size of a part to automatically obtain and store the size of the part (see, for example, Japanese Patent Application Laid-Open No. 07-38294).

In recent years, a so-called multi-function mounter on which various electronic parts ranging from minute parts to large parts have been widely used.

If a detector for detecting dimensions (specifically, the height of a component) is applied to such a multifunctional mounter, the following problems occur. If the detector is attached to the transfer head of the mounter, the height of the part can be measured from the time the transfer head picks it up by suction until it moves over the board, so that no time is wasted in height measurement. On the other hand, large-sized detectors are required to detect the height of larger components. If such a detector is attached to a transfer head of a mounter, the size and weight of the detector place a burden on the transfer head that moves at high speed to mount components, so that the positioning accuracy of the transfer head cannot be maintained.

Furthermore, since a large-sized detector generally has low resolution, if the detector detects the height of a minute component, the height measurement error becomes so large that the component cannot be mounted without any problem. A large-sized detector with high resolution inevitably leads to an increase in cost.

Contents of the invention

Therefore, the present invention was conceived in consideration of the above problems, and an object of the present invention is to provide a method for measuring various parts ranging from minute parts to larger parts using a sensor with a small measuring range the height of.

In order to achieve the above objects, a component height measuring method according to the present invention is a component height measuring method applied to a mounter equipped with a transfer head having a component suction-holding nozzle for For transferring a part and mounting the part on a board, the method includes: lowering the part within the high precision range of a sensor for measuring the height of the part; and measuring the height of the part using the sensor high.

Accordingly, since the height of the part is measured after the part is lowered within the high precision range of the sensor, the height of the part can be accurately measured.

The method further includes preliminarily lowering the part picked up and held by the suction nozzle, and preliminarily measuring a height of the part using the lowering amount of the suction nozzle and a signal output from the sensor. In the step of lowering the component, the component is preferably lowered within the high accuracy range of the sensor based on the height of the component measured in the preliminary measurement.

Accordingly, since the height of the part is measured based on the lowering amount of the suction nozzle and the signal output from the sensor, it is possible to measure the height of various parts ranging from minute parts to larger parts, even if The sensors are relatively small. In addition, even with sensors whose accuracy varies from one position to another, high measurement accuracy can be ensured by measuring the part twice.

It is further preferred that the method comprises: lowering the suction nozzle of the unholding part and obtaining information related to the vertical position of the lower end of the suction nozzle.

Accordingly, for a mounter that needs to replace the suction nozzle, it becomes possible to avoid the influence of the dimensional accuracy or attachment accuracy of the suction nozzle on the height measurement value of the component as much as possible.

Preferably, when measuring the height of the part, in the case where the measured height is smaller than a predetermined value, the height of the part is deterministically measured while maintaining the vertical position of the lower end of the suction nozzle at a predetermined position , and in a case where the measured height is equal to or greater than a predetermined value, the height of the part is deterministically measured while maintaining the vertical position of the lower end of the suction nozzle at a predetermined position.

Correspondingly, when measuring the height of relatively small parts, the repetition error of the suction nozzle rather than its reduction error has a greater influence on the measured value of the part height. Conversely, for relatively thick parts, the lowering error of the nozzle has a greater influence on the measured part height. When the repetition error is smaller than the reduction error, the possibility of a severe error in component height can be reduced.

Note that the lowering error is an error between the value set for lowering the suction nozzle and the actual lowering amount of the suction nozzle. The repetition error is the variation error between the actual lowering value of the nozzle when the set value is lowered repeatedly several times.

In addition, one of the preliminary measurement and the definitive measurement is performed when the sensor and the part are moved relative to each other on a horizontal plane after holding the suction nozzle in a stationary state.

Accordingly, the sensor can be removed in order to install the components. It is also possible to measure multiple parts at once.

In addition, a program for causing a computer to execute the above steps, a height measuring device including the above steps as a unit, or a mounter including the height measuring device can also achieve the above-mentioned same object and produce the above-mentioned same effect .

According to the present invention, the heights of various components ranging from minute components to large components can be measured using a high-precision portion of a small sensor, so that the height of electronic components can be detected at a high-precision level.

As further information regarding the technical background of the present application, the disclosure of the following Japanese patent application including specification, drawings and claims is hereby incorporated by reference in its entirety:

Japanese Patent Application No.2005-223681 filed on August 2, 2005;

Japanese Patent Application No. 2005-224892 filed on August 3, 2005; and

Japanese Patent Application No. 2005-237334 filed on August 18, 2005.

Description of drawings

These and other objects, advantages and features of the invention will become apparent from the following description of the invention taken in conjunction with the accompanying drawings showing specific embodiments of the invention. In the attached picture:

FIG. 1 is a conceptual diagram illustrating a conventionally sized detector;

2 is a plan view of an electronic component mounter in one embodiment of the present invention;

3A is a front view of a delivery head of an electronic component mounter in one embodiment of the present invention;

Figure 3B is a side view of the transfer head of the electronic component mounter in one embodiment of the present invention;

Fig. 4 is a structural diagram of the control system of the electronic component mounter in one embodiment of the present invention;

FIG. 5 is a diagram explaining a method for detecting electronic components in one embodiment of the present invention;

Fig. 6 is a flow chart of the operation sequence of the electronic component mounter in one embodiment of the present invention;

FIG. 7A is a diagram for explaining a first method for detecting electronic parts in one embodiment of the present invention;

7B is a diagram for explaining a second method for detecting electronic components in one embodiment of the present invention;

Fig. 8 is a flow chart of the operation sequence of the electronic component mounter in one embodiment of the present invention;

9 is an external perspective view of an electronic component mounter according to an embodiment of the present invention, with a cross-sectional view of the mounter interior;

10 is a plan view showing an internal structure, including main elements of the electronic component mounter;

Figure 11A is a top perspective view of a delivery head;

Figure 1 IB is a bottom perspective view of the transfer head;

12 is a conceptual side view showing a projector and a line sensor attached to a scanning measurement unit;

FIG. 13 is a functional block diagram showing the functional structure of the electronic component mounter;

Fig. 14 is a flowchart of the operation sequence of the electronic component mounter;

15 is a side view showing preliminary measurements of electronic components;

Figure 16 is a side view illustrating deterministic measurement of electronic components;

Fig. 17 is a flow chart showing the operation sequence for measuring the relationship between the set value for lowering the suction nozzle and the actual lowering amount;

Fig. 18 is a side view showing the measurement of the lowering amount of the suction nozzle;

19 is a flow chart showing the sequence of operations for measuring the height of an electronic component in one embodiment of the present invention;

20 is a side view showing an arrangement of relatively thick electronic components for measuring the relatively thick electronic components; and

Fig. 21 is a side view showing an arrangement of relatively thin electronic parts for measuring the relatively thin electronic parts.

Detailed ways

(first embodiment)

Next, an embodiment of the present invention is described with reference to the drawings. Fig. 2 is a plan view of the electronic component mounter in one embodiment of the present invention; Fig. 3 A is the front view of the delivery head of the electronic component mounter in one embodiment of the present invention; Fig. 3 B is an embodiment of the present invention The side view of the transfer head of the electronic component mounter; Fig. 4 is a structural diagram of the control system of the electronic component mounter in one embodiment of the present invention; Fig. 5 is an explanation for detecting electronic 6 is a flowchart of the operation sequence of the electronic component mounter in one embodiment of the present invention.

First, referring to FIG. 2 , FIG. 3A and FIG. 3B , the overall structure of the electronic component mounter will be described. In FIG. 2 , a conveyance path 2 extending in the X direction is placed approximately at the center of the base 1 . The conveyance path 2 conveys the board 3 on which components are to be mounted, and places it at a predetermined position. Note that in the present invention, the conveying direction of the board is the X direction, and the direction orthogonal to the X direction on the horizontal plane is the Y direction. Electronic component supply units 4 are placed on both sides in the Y direction of the conveyance path 2 . Each electronic component supply unit 4 includes a component feeder for supplying electronic components (hereinafter referred to as "components") to the mounter. In this embodiment, a plurality of tape feeders 5 are detachably arranged side by side. A plurality of components are stored in the tape feeder 5 .

A pair of Y coordinate stages 6 are placed at both ends of the base 1 in the X direction. A pair of X-coordinate stages is provided on these two Y-coordinate stages 6, and is driven by the Y-coordinate stages 6 to move along the Y-axis. The transfer head 8 is attached to the side of each X-coordinate stage 7, and is driven by the X-coordinate stage 7 so as to move along the X-axis. The Y coordinate stage and the X coordinate stage 7 are horizontal moving units for horizontally moving the transfer head 8 on the base 1 .

In FIGS. 3A and 3B , the transfer head 8 is attached to the X-coordinate stage 7 via a plate 9 . A plurality of suction nozzle units 20 are attached to and supported by the frame 10 . In this embodiment, two rows of suction nozzle units are placed in the Y direction, and each row has four suction nozzle units 20 arranged in series.

In FIG. 3B , a suction nozzle 21 is attached to the lower end of each suction nozzle unit 20 . Each suction nozzle unit 20 includes an up-and-down drive unit (up-and-down drive unit) 22 and a rotation drive unit 23 (see FIG. 4 ) as units for driving the suction nozzle 21. The up and down drive unit 22 is made up of the following parts: a ball screw (ball screw) (not shown) fixed in the vertical direction; a nut screwed together with the ball screw; and a motor for axially rotating the ball screw , the suction nozzle 21 is connected to the nut. The axial rotation of the ball screw moves the nut vertically, which causes the suction nozzle 21 to move up and down. As described above, by controlling the driving of the up-and-down driving unit 22 of each nozzle unit 20, the level (vertical position) of each nozzle 21 can be adjusted independently from other nozzles. In addition, since each suction nozzle 21 is driven to rotate independently of other suction nozzles by the rotation drive unit 23 , the horizontal direction of the component picked up and held by each suction nozzle 21 can be changed.

In FIGS. 3A and 3B , the first row of sensors 13 is attached to the transfer head 8, and is held at a position where the sensors 13 can detect the component suction surface (hereinafter referred to as "suction surface") on the lower surface of each suction nozzle 21. at a fixed level on the side. The first row of sensors 13 is able to move along the array of suction nozzles 21 while maintaining the fixed level. The first line sensor 13 detects the part P when it is on the side of the part P picked up and held by each suction nozzle 21 . The first row of sensors 13 continues to move, thereby detecting parts P sequentially. In this way, the first row sensor 13 detects the height of each component P picked up and held by each suction nozzle 21 and the level of its mounting surface. Note that the mounting surface is the surface of the component that is to come into contact with the upper surface of the board when the component is mounted on the board. The mounting surface is usually the lower surface of the electrode, but the mounting surface of a component having a bump is the lower surface of the bump. The first row of sensors 13 acts as a second detection means which detects the part picked up and held by the multi-nozzle unit at the side of the part.

In FIG. 2 , the second row of sensors 14 is placed between the conveying path 2 and the electronic component supply unit 4 , detecting components sucked and picked up by the suction nozzles 21 of the transfer head 8 below the components. The second line sensor 14 takes an image of the component mounting surface, and the image is processed by an image processing unit 39 (see FIG. 4 ) to detect the presence or absence of the component, the suction posture of the component, and the like. The second row of sensors 14 acts as a first detection means, which detects the part picked up and held by the multi-nozzle unit below the part.

Next, the configuration of the control system of the electronic component mounter will be described with reference to FIG. 4 . The control unit 30 is connected to the conveying path 2, the Y coordinate stage 6, the X coordinate stage 7, the first row sensor 13, the second row sensor 14, and the drive system via the bus 31, that is, the up and down drive unit 22 of the suction nozzle unit 20 and the rotary The driving unit 23, and it controls the driving of each driving system based on the NC program 37. The NC program is stored in a data unit 32 connected to the bus 31 , which stores a parts library 33 , nozzle data 34 , plate data 35 , control parameters 36 in addition to the NC program 37 . The parts library 33 stores part size data 33a for each part type. The nozzle data 34 stores reference level data 34a of each nozzle 21, which is the basis for measuring the height of components. The reference level data 34a is data representing the level of the tip of the suction nozzle 21 for measuring the height of the component, or represents the downward stroke from the upper limit of the level of the suction nozzle 21, and includes Pick up the level data of the surface. The control unit 30 is also connected to a calculation unit 38 , an image processing unit 39 , a display unit 40 , and an operation/input unit 41 via a bus 31 .

Next, a method for detecting components by the first line sensor 13 and the second line sensor 14 is described with reference to FIG. 5 . FIG. 5 shows the positional relationship among the parts P sucked and held by the respective suction nozzles 21 , the first line sensor 13 and the second line sensor 14 . Each nozzle holds a different size part. Here, the tiny parts are 0402, 0603 and 1005 chip parts, which have slight differences in dimensions (eg, length, width, height, etc.). Such minute parts also include 1608R and 2625R chip parts, and other chip parts that do not have such a slight size difference but have a height of 0.5 mm or less.

Note that, in the present embodiment, the above-mentioned minute parts are taken as examples of parts to be sucked, but the present invention is not limited to such minute parts, and any other parts may be used.

Each suction nozzle 21 is driven by the up-and-down driving unit 22 so that its level is adjusted based on the reference level data 34a of each suction nozzle 21 . The reference level of each suction nozzle 21 is set so that not only the side surface of each part P that each suction nozzle 21 picks up and holds is within the high-precision portion of the first line sensor 13 , that is, within the detection range (from the upper limit L1 to the lower limit L2 ), and the mounting surface of each part P is within the focus range (detectable range) of the second line sensor 14 . As described above, the reference level of each suction nozzle 21 must be set just so that the sucked part P is within the above-mentioned detectable range. Regardless of the size of the part P to be picked up, the up and down driving unit 22 is controlled so that the measurement level for measuring the height of each suction nozzle 21 is maintained at the reference level, thus detecting the height of the part P using the high precision of the measurement level. high.

As for the parts P picked up and held by the respective suction nozzles 21 adjusted to be located at the respective reference levels, the sides of the parts P are within the detectable range of the first line sensor 13 (upper limit L1 to lower limit L2), and the parts P The mounting surface of is located within the focus range (detectable range) of the second line sensor 14. Therefore, by moving the first row of sensors 13 horizontally along the sides of the components P while keeping the level constant, it is possible to continuously detect the level of the mounting surfaces of these components P. Furthermore, by sequentially moving the components P sucked and held by the respective suction nozzles 21 above the second line sensor 14, images of the mounting surface of the components P can be continuously taken.

Each is obtained by the calculation unit 38 by calculating the difference between the level of the mounting surface of the component P detected by the first row sensor 13 and the level of the suction surface of the suction nozzle 21 contained in the reference level data 34a. The height of part P.

As described above, the first row sensor 13 can detect the component P with a high degree of accuracy by lowering the component P sucked and held by each suction nozzle 21 to a level at which the first row sensor 13 can measure the height of the component P. .

(second embodiment)

Next, another embodiment of the present invention is described.

The purpose of the second embodiment is as follows.

According to the method described in the published patent reference (Japanese Patent Application Laid-Open No. 2002-09496), the mounting surface of the part P sucked and held by each suction nozzle 21 and the focal position of the second line sensor 14 are aligned. The levels are aligned regardless of the heights of the individual parts P, so that the level of the suction nozzle 21 is adjusted to a level obtained by subtracting the heights of the individual parts P from the level of the focus position. More specifically, the level height of each suction nozzle 21 is governed by an absolute value. The level of each suction nozzle 21 is adjusted by coupling the suction nozzle 21 with a nut screwed on the ball screw and controlling the axial rotation of the ball screw. Therefore, when the level of the suction nozzle 21 is adjusted, the error caused by the machining accuracy of the ball screw has a direct influence on the up and down movement of the suction nozzle 21 . For example, the error is about ±50 μm with respect to a stroke of 300 mm. Therefore, when the level of each suction nozzle 21 is managed by an absolute value, the level also includes an error of about ±50 μm.

Due to the current reduction in the size and weight of the part P, the difference between the height of the part P measured when the part P is normally picked up and the height measured when the part P is not picked up normally (in such a way that the part P is picked up obliquely) There are only slight size differences. For example, the width and slope length of the 0603 chip micropart P are 0.3 mm and 0.35 mm, respectively, and the difference between them is 0.05 mm (ie, 50 μm).

In other words, it is necessary to judge whether such minute parts P are picked up normally by accurately detecting a difference of only 50 μm. Therefore, if the height including an error of the same level is detected for such a minute component P picked up and held by the suction nozzle 21 , the suction posture of the minute component P may be incorrectly detected.

Therefore, as an example, the present embodiment shows a method for accurately and efficiently detecting and measuring the height of an electronic component (specifically, a minute component) picked up and held by the suction nozzle 21 . Note that the structure of the electronic component mounter in this embodiment is the same as that in the above first embodiment.

In order to detect parts P picked up by each suction nozzle 21 that repeats the mounting operation, the measurement level of each suction nozzle 21 is controlled so as to be a reference level predetermined for each suction nozzle 21 . The height of the newly sucked part P is determined by calculating the difference between the level of the mounting surface of the part P detected by the first row sensor 13 and the level of the suction surface of the suction nozzle 21 contained in the reference level data 34a. acquired.

In other words, if the component to be measured is a minute component, it is possible to keep the measurement level of each suction nozzle 21 constant when measuring the component height using the first row of sensors 13 .

If the measurement level of the suction nozzle 21 is kept constant, the nut of the upper and lower drive unit 22 is repeatedly screwed with the ball screw at the same position as the suction nozzle level control unit. Therefore, it is possible to limit the influence of machine errors caused by the machining accuracy of these nuts and ball screws. Thereby, it is made possible to reduce variation in the measured level of the suction surface of the suction nozzle 21 adjusted based on the reference level data 34a, and thus it is possible to measure the height of the component P with high accuracy.

Note that the reference level of each suction nozzle 21 can be set arbitrarily as long as the parts P picked up and held by the suction nozzle 21 are within the detectable ranges of the first line sensor 13 and the second line sensor 14 respectively. Since the measurement level of each suction nozzle 21 is independently adjusted to its own reference level, the height of the part P picked up and held by each suction nozzle 21 can be measured with high accuracy.

Note that although the part P is shown larger than it actually is in FIG. 5, the actual size of the part P is very minute and there is no perceivable difference between their heights. Therefore, the second line sensor 14 can continuously take images of the mounting surfaces of all components P without horizontally aligning the mounting surfaces thereof.

Next, the operation sequence of the electronic component mounter will be described with reference to FIG. 6 . After the mounting starts, the multi-nozzle unit is moved to a pick-up position on the tape feeder 5 provided in the electronic component supply unit 4 so that the respective suction nozzles 21 can pick up the component P (S1). After the parts are picked up, the levels of the suction nozzles 21 are respectively adjusted to their reference levels (S2). Next, the first row sensor 13 is moved, the parts P picked up and held by the suction nozzles are detected from their sides, and the level of the mounting surface of each part P is obtained (S3). The suction nozzles 21 that have picked up the parts P are sequentially moved over the second line sensor 14 so that the second line sensor 14 can detect the parts P from below the respective parts P and capture an image of the mounting surface of the parts P (S4). More specifically, S3 and S4 are processes of detecting the part P from the side and below of the part P sucked and held by the level-adjusted suction nozzle 21 of the multi-nozzle unit.

Next, based on the difference between the level of the mounting surface of the part P detected in S3 and the level of the suction surface of the suction nozzle 21 contained in the reference level data 34a, the weight of each part P is calculated. height, and compare it with the size data 33a in the parts library 33. In the case where the calculated height of the part P exceeds the tolerance range of the height of the part P contained in the dimension data 33a, it is determined that the part P is sucked and held in an abnormal posture (such as a vertical position and an inclined position), Instead of the normal posture with its mounting surface facing down, and abnormal suction processing (S5) is performed. The image processing unit 39 processes the image of the mounting surface of each component P captured in S4 based on the dimension data 33a. When it is judged that the component P cannot be mounted due to its wrong size and displacement, abnormal suction processing is performed ( S6 ). In S5 or S6, abnormal suction processing is performed, the part P is discarded, and a new part P is picked up (S1). The above operations of S2 to S4 are repeated for the newly picked-up part P, and when the detected number of abnormal pick-ups exceeds a predetermined number of times, this situation is regarded as an error, and the machine is stopped.

When it is detected in S3 and S4 that the part P is sucked and held in a normal posture, the position of the part P is corrected by horizontal movement, vertical movement, and rotation of the suction nozzle 21 (S7), and then the part P is mounted on its Mounting position on board 3 (S8).

Thereafter, the above installation operations from S1 to S8 are repeatedly performed until the component installation is completed. The measured level of each suction nozzle 21 for picking up a new part P in each repetition is adjusted to its own reference level (S2). In other words, S2 is a process in which, each time the mounting operation is repeated, the level of each nozzle in the multi-nozzle unit for repeatedly picking up new electronic parts is adjusted to a predetermined level for each nozzle. , on its own base level.

The component may be detected (S3) by the first row sensor 13 before it is detected (S4) by the second row sensor 14, and vice versa. Both tests can be performed simultaneously. Since the first row of sensors 13 is attached to the transfer head 8 in this embodiment, it is possible to detect components while the transfer head 8 is moving. In other words, the part P can be detected by the first line sensor 13 while the suction nozzle 21 that sucks and holds the part P moves over the second line sensor 14 and the board 3 . Therefore, the speed and efficiency of mounting operations can be improved. Note that it is also possible to inspect the part by placing the first row of sensors 13 on the base 1 and moving the transfer head 8 along the side of the first row of sensors 13 .

As described above, according to the electronic component mounter and mounting method of the present invention, the height of the components picked up and held by the respective suction nozzles of the multi-nozzle unit can be measured using the high accuracy of the measurement level of the suction nozzles, and it is possible to The parts picked up and held by the multi-nozzle unit are continuously detected. Therefore, components can be detected with high efficiency and high precision, so that not only defective boards can be avoided but also the performance of the mounter can be improved.

(third embodiment)

Next, a method for detecting components by the first line sensor 13 and the second line sensor 14 is described with reference to FIG. 7 . In this embodiment, the components to be installed are classified into first components and second components, and different detection methods are used to detect the first components and the second components respectively. Note that the structure of the electronic component mounter in this embodiment is the same as that of the first and second embodiments above.

In this embodiment, the first component is a tiny component, such as 0402, 0603 and 1005 chip capacitors, and they have slight differences in dimensions (eg, length, width, height, slope length, etc.). Such tiny parts also include 1608R and 2625R chip capacitors and other chip parts, which do not have this slight difference in size, but instead have a height of 0.5mm or less. On the other hand, the second part is a relatively large part that is not classified as the first part. The height of the first part did not vary significantly between types, while the height of the second part varied greatly between types.

First, a method for detecting the first component is described with reference to FIG. 7A. FIG. 7A shows the positional relationship between the first part P1 sucked and held by the respective suction nozzles 21 , the first line sensor 13 and the second line sensor 14 .

Each suction nozzle 21a holds the 1st part P1 of a different size. Each suction nozzle 21a is driven by the up-and-down drive unit 22 so as to adjust its level based on its own reference level data 34a. The reference level of each suction nozzle 21a is set so that not only the side surface of each first part P1 sucked and held by each suction nozzle 21a is within the detectable range of the first line sensor 13 (from the upper limit L1 to the lower limit L2 ), and the mounting surface of each first part P1 is within the focus range (detectable range) of the second line sensor 14 .

For all the first parts P1 picked up and held by the respective suction nozzles 21a adjusted to their respective reference levels, the sides of these first parts P1 are within the detectable range of the first line sensor 13 (from the upper limit L1 to the lower limit). L2), and its mounting surface is located within the focus range (detectable range) of the second line sensor 14. Therefore, by moving the first row sensor 13 along the side of the first part P1 while maintaining a fixed level, it is possible to continuously detect the level of the mounting surface of each first part P1. Furthermore, by sequentially moving the first components P1 sucked and held by the respective suction nozzles 21 a over the second line sensor 14 , images of the mounting surfaces of the respective first components P1 can be continuously taken.

By calculating the difference between the level of the mounting surface of the first part P1 detected by the first line sensor 13 and the level of the suction surface of the suction nozzle 21a contained in the reference level data 34a by the calculation unit 38 , to get the height of each first part P1.

In order to detect the first part P1 picked up by each suction nozzle 21a repeating the mounting operation, the measurement level of each suction nozzle 21a is controlled so as to be the reference level of the suction nozzle 21a. The new suction is obtained by calculating the difference between the level of the mounting surface of the first component P1 detected by the first line sensor 13 and the level of the suction surface of the suction nozzle 21a contained in the reference level data 34a. The height of the first component P1.

In other words, if the part to be inspected is a minute part such as the first part P1, it is possible to keep the measurement level of the suction nozzle 21a constant while using the first row sensor 13 to measure the part height.

If the measured level of the suction nozzle 21a is kept constant, the nut suction nozzle of the up-and-down drive unit 22 as a nozzle level control unit repeats screwing with the ball screw at the same position. Therefore, it is possible to limit the influence of machine errors caused by the machining accuracy of these nuts and ball screws. Thereby, variation in the measured level of the suction surface of the suction nozzle 21a adjusted based on the reference level data 34a can be reduced, and thus the height of the first part P1 can be measured with high precision.

Note that the reference level of each suction nozzle 21 a can be set arbitrarily as long as the first part P1 sucked and held by the suction nozzle 21 a is within the detectable ranges of the first line sensor 13 and the second line sensor 14 , respectively. Since the measurement level of each suction nozzle 21a is independently adjusted to the reference level, it is possible to measure the level of the first part P1 sucked and held by each suction nozzle 21a with high accuracy.

Note that although the first part P1 is shown larger than it actually is in FIG. 7A , the actual size of the first part P1 is very minute and there is no perceivable difference between their heights. Therefore, the second line sensor 14 can continuously take images of the mounting surfaces of all the first components P1 without horizontally aligning the mounting surfaces thereof.

Next, a method for detecting the second component is described with reference to FIG. 7B . FIG. 7B shows the positional relationship between the second part P2 sucked and held by the respective suction nozzles 21 b and the second line sensor 14 . Each suction nozzle 21b holds the 2nd part P2 of a different size.

Each suction nozzle 21b is driven by the up and down driving unit 22, thereby adjusting the level of the suction nozzle 21b based on the size data 33a of each second part P2, and setting the level of the mounting surface of all the second parts P2 within the level L3 Horizontal alignment. The level L3 is set to a value within the focus range (detectable range) of the second line sensor 14, and by sequentially moving the second member picked up and held by the respective suction nozzles 21b over the second line sensor 14 P2, images of the mounting surfaces of the respective second components P2 may be continuously taken.

As described above, the second line sensor 14 can continuously detect the second parts P2 by aligning the mounting surfaces of the respective second parts P2 (the heights of which vary significantly between different types) on the horizontal plane. Note that reference numerals 21a and 21b are assigned to the suction nozzle 21 for illustration purposes, and the suction nozzle 21a and the suction nozzle 21b are the same suction nozzle 21 .

Next, the operation of the electronic component mounter will be described with reference to FIG. 8 . First, it is determined whether the component to be mounted is the first component or the second component (S21). If the components to be mounted are the first components, the levels of the suction nozzles 21 are respectively adjusted to their reference levels after the components are sucked (S22). Next, the first row sensor 13 is moved to detect the first parts P1 picked up and held by the suction nozzles from their sides, and the level of the mounting surface of each first part P1 is obtained (S23). The suction nozzles 21 that have picked up the first parts P1 are sequentially moved above the second line sensor 14, so that the second line sensor 14 can detect them from below the first parts P1, and photograph the images of the respective first parts P1. An image of the mounting surface (S24). More specifically, S23 and S24 are a first detection process for detecting a first part from the side and lower surface of the first part sucked and held by the level-adjusted suction nozzle 21 of the multi-nozzle unit.

Next, based on the difference between the level of the mounting surface of the first component P1 detected in S23 and the level of the suction surface of the suction nozzle 21 contained in the reference level data 34a, each second The height of a part P1 is compared with the size data 33a in the part library 33. In a case where the calculated height of the first part P1 exceeds the tolerance range of the height of the first part P1 included in the dimension data 33a, it is determined that the first part P1 is in an abnormal posture (such as a vertical position and an inclined position) is sucked and held instead of the normal posture with its mounting surface facing downward, and abnormal suction processing is performed (S25). The image processing unit 39 processes the image of the mounting surface of each first component captured in S24 based on the dimension data 33a. When it is determined that the component cannot be mounted at the correct position due to its wrong size and displacement, abnormal suction processing (S26) is performed. In S5 or S6, abnormal suction processing is performed, the first part is discarded, and a new first part is picked up (S21). Repeat the above operations of S22 to S24 for the newly picked-up first part, and when the detected number of abnormal pick-ups exceeds a predetermined number of times, this situation is regarded as an error, and the machine is stopped.

When it is detected in S23 and S24 that the part P is sucked and held in a normal posture, the position of the first part is corrected by horizontal movement, vertical movement and rotation of the suction nozzle 21 (S27), and then the first part is mounted on the It is in its installed position on the board 3 (S28).

Afterwards, the above installation steps from S21 to S28 are repeated until the installation operation is completed. The measurement level of each suction nozzle 21 for picking up a new part P in each repetition is adjusted to its own reference level (S22). In other words, S22 is a first adjustment process in which, each time the mounting operation is repeated, the level of each nozzle in the multi-nozzle unit for repeatedly picking up new electronic components is adjusted to the level of each nozzle. predetermined, its own reference level.

On the other hand, if the parts to be mounted are the second parts, the levels of the suction nozzles 21 are respectively adjusted based on the size data 33a, and the levels of the mounting surfaces of all the second parts are horizontally aligned on the same level (S29 ). S29 is a second adjustment process in which the level of each nozzle in the multi-nozzle unit is adjusted so that the levels of the mounting surfaces of all the second components sucked and held by the nozzles are horizontally aligned at the same level.

Next, the suction nozzles 21 that have picked up the second components are sequentially moved above the second line sensor 14, so that the second line sensor 14 can detect them from below the second components, and photograph the images of the respective second components. An image of the installation surface (S30). S30 is a second inspection process for inspecting the second component from the lower surface of the second component, and the mounting surfaces of the second component are aligned at the same level.

The image processing unit 39 processes the image of each second component mounting surface captured in S30 based on the size data 33a, and if abnormal suction such as a positional deviation is detected, is removed by rotational driving or horizontal movement of the suction nozzle 21. The position of the second part is corrected (S31). The second component detected as being sucked and held in the normal posture or whose position was corrected in S30 is mounted to its mounting position on the board 3 (S32). Hereinafter, the above installation steps from S29 to S32 are repeated until the installation operation is completed.

A component may be detected by the first row sensor 13 before it is detected by the second row sensor 14, and vice versa. Both tests can be performed simultaneously. In the present embodiment, since the first row sensor 13 is attached to the transfer head 8, it is possible to detect components while the transfer head 8 is moving. In other words, the first component can be detected by the first row sensor 13 while the suction nozzle 21 sucking and holding the first component moves over the second row sensor 14 and the board 3 . Therefore, the speed and efficiency of mounting operations can be improved. Note that it is also possible to inspect the part by placing the first row of sensors 13 on the base 1 and moving the transfer head 8 along the side of the first row of sensors 13 .

As described above, according to the electronic component mounter and mounting method of the present invention, the component detection method is different between the types of components to be mounted (ie, the first component and the second component). Therefore, the component to be mounted can be detected using a detection method suitable for the type of the component to be mounted. In addition, for the first part which is a minute part, the height of the part picked up and held by each nozzle of the multi-nozzle unit can be measured using the high-accuracy measurement level of the nozzle, and it is possible to continuously detect The part picked up and held by the nozzle unit. Therefore, components can be detected with high efficiency and high precision, so that not only defective boards can be avoided but also the performance of the mounter can be improved.

(fourth embodiment)

Next, embodiments of the present invention will be described with reference to the drawings. In this embodiment, a detailed measurement method is described for general components other than minute components described in the third embodiment above.

9 is an external perspective view of a component mounter with a cutaway view of the mounter's interior in accordance with one embodiment of the present invention.

The mounter 100 shown in the figure can be incorporated into a mounting line, and it mounts electronic components received from upstream of the mounting line onto boards, and sends circuit boards (boards on which electronic components have been mounted) to downstream equipment. This mounter 100 is equipped with suction nozzles that hold electronic components by means of vacuum suction, and includes: a transfer head 110 equipped with suction nozzles that transfers the sucked and held components to a board; an XY robot unit 113 that The transfer head 110 is moved in the horizontal direction; and a component supply unit 115 that supplies the suction nozzle unit 112 with components.

More precisely, the mounter 110 is a mounter capable of mounting various electronic components on a board, including minute components and larger components such as connectors, and a device capable of mounting various electronic components. High-speed, multi-function mounters for tiny components, such as resistors and capacitors, and larger IC components, such as quad flat packs (QFPs) and ball grid arrays (BGAs).

FIG. 10 is a plan view showing the main internal structure of the component mounter 100 .

The installer 100 also includes: a nozzle station (station) 119, wherein the nozzles to be attached to the nozzle unit 112 for replacement are stored, to be suitable for various types and shapes of parts; a path of the board 120; a mounting table 122 on which the board 120 is placed for mounting electronic components on the conveyed board 120; and a parts collection device 123 which, in the case where the sucked and held parts are defective Collect electronic parts.

Component supply units 115 are provided on the front and back of the mounter 100, and include a component supply unit 115a composed of a supply box for supplying electronic components placed in a carrier tape; and a component supply unit 115b that supplies components placed in a tray. electronic components, the tray is divided according to the size of the components.

11 is a perspective view of the delivery head 110 , specifically, FIG. 11A is a top perspective view of the delivery head 110 , and FIG. 11B is a bottom perspective view of the delivery head 110 .

As shown in FIG. 11 , the transfer head 110 is a unit that obtains a plurality of electronic components from a component supply unit 115, transports these electronic components over the board, and mounts them at predetermined positions on the board, and the transfer head 110 includes: a plurality of suction nozzle units 112; suction nozzles 111 as holding units, which are replaceably attached to corresponding suction nozzle units 112; and a scanning measurement unit 130, which can move in the direction in which the suction nozzle units 112 are arranged. .

The suction nozzle unit 112 is a unit capable of suctioning and holding one electronic component, and has a driving mechanism for vertically driving the suction nozzle 111 and a mechanism for vacuum suctioning the electronic component using the suction nozzle 111 .

The suction nozzle 111 has a tip adapted to the shape of the electronic component to be sucked, and is equipped with an aperture for vacuum suction of the component. As mentioned above, the suction nozzle 111 can be interchanged with another suction nozzle depending on the electronic component to be held.

The scanning measurement unit 130 is a U-shaped part that can move in the X direction in FIG. 10 under and along the side of the electronic part while the suction nozzle 111 is holding the part.

FIG. 12 is a side view schematically showing the projector 131 and the first line sensor 132 attached to the scanning measurement unit 130 .

As shown in FIG. 12, the scanning measurement unit 130 is equipped with a projector 131 on one side wall for projecting light inside the scanning measurement unit 130, and on the other side wall of the scanning measurement unit 130, is equipped with a projector 131 placed vertically. The first row sensor 132 is used to receive the light projected from the projector 131 .

Note that FIG. 12 schematically shows the scanning measurement unit 130 viewed from the X direction in FIG. 11 . In FIG. 12 , 111 denotes a suction nozzle, and P denotes an electronic component to be picked up by the suction nozzle 111 .

In addition, the scanning measurement unit 130 is equipped with a second row of sensors 133 at the bottom, which faces the bottom surface of the electronic component held by the suction nozzle 111 , so as to capture an image of the component.

The first line sensor 132 is a one-dimensional sensor on which light receiving elements are vertically placed, capable of determining the vertical position where light (horizontal light beam) from the projector 131 is blocked with high resolution (for example, 10 μm resolution). However, the nature of the first row sensor 132 brings high resolution and high reliability in repeatability etc. in its central part, but gradually towards the ends of the first row sensor 132 resolution and reliability reduce. Furthermore, the measurable range of the first row sensor 132 in the present embodiment is a range in which the height of a large electronic part P (for example, 3 mm) cannot be measured.

FIG. 13 is a functional block diagram showing the functional configuration of the component mounter 100 .

As shown in the figure, the component mounter 100 includes: a mechanism unit 101 that lowers the electronic component P and sweeps the scanning measurement unit 130 to measure the height of the electronic component P; and a height measurement unit 140 that controls the mechanism unit 101, To measure the height of electronic components P.

As mentioned above, the mechanism unit 101 includes: the suction nozzle unit 112, which moves the suction nozzle 111 up and down, and is equipped with an encoder 114, which outputs the lowering amount of the suction nozzle 111 as a digital signal; and a scanning measurement unit 130, which A first row of sensors 132 is provided, and can slide in a direction toward the nozzle unit 112 .

Note that although the mechanism unit 101 of the mounter 100 is equipped with other devices and the like, description thereof is omitted. In addition, the mechanism unit 101 also has a function of mounting the electronic component P on the board 120 .

The height measurement unit 140 is composed of a computer and its peripheral devices, controls the mechanism unit 101 so that it performs operations required to measure the height of the electronic part P, analyzes data obtained from the mechanism unit 101 to calculate the height of the electronic part P, and its storage. The height measurement unit 140 includes: a measurement unit 141, which obtains a signal from the encoder 114 in the suction nozzle unit 112 and a signal from the first line sensor 132 in the scanning measurement unit 130; a height calculation unit 142, which analyzes the signal obtained by the measurement unit 141 to obtain the signal, etc., and calculate the height of the electronic component P; the head control unit 143, which controls the movement of the suction nozzle unit 112; the scanning control unit 144, which controls the movement of the scanning measurement unit 130; the global control unit 145, which The above two control units 143 and 144 ; and the storage unit 146 are controlled.

The head control unit 143 is a processing unit that controls the vertical movement of the suction nozzle 111 attached to the suction nozzle unit 112 . More specifically, the head control unit 143 obtains a signal from the encoder 114 in the suction nozzle unit 112 via the measurement unit 141, performs feedback control based on the signal, and controls the vertical motion of the suction nozzle 111 with high precision (for example, 1 μm). Position to lower the suction nozzle 111 to the set value obtained by the head control unit 143 , that is, the set lowering amount of the suction nozzle 111 , which is input in advance and stored in the storage unit 146 .

The scanning control unit 144 is a processing unit that controls the movement of the scanning measurement unit 130 in the alignment direction of the suction nozzle unit 112, and has an electronic function for controlling the stop and moving direction of the scanning measurement unit 130 and specifying that the first row sensor 132 is measuring. The function of the suction nozzle unit 112 of the part P.

For example, a method for specifying the part P being measured can be used for specifying the part to be measured and for scanning measurement by associating the movement amount of the scanning measurement unit 130 with the position of each suction nozzle 111 in the scanning direction for specifying the part P being measured. The nozzle unit 112 is specified by the method of the measurement order in the moving direction of the unit 130, and the like.

The global control unit 145 is a processing unit for controlling the head control unit 143 and the scan control unit 144 based on a program stored in the storage unit 146 so that they can preliminarily measure parts in the case of preliminary measurement, and The head control unit 143 and the scan control unit 144 are controlled such that they can deterministically measure components in the case of deterministic measurement. The global control unit 145 determines the height of the electronic part P for preliminary measurement, and controls the head control unit 143 to perform deterministic measurement according to the determination result in the preliminary measurement.

Here, the preliminary measurement is a process of lowering the suction nozzle 111 so that the lower surface of the part P enters the measurement range of the first row sensor 132 and preliminarily measuring the height of the part P by the first row sensor 132 .

The deterministic measurement is a process of lowering the suction nozzle 111 so that the lower surface of the part P is within the high-precision range of the first row sensor 132 based on the height of the part P obtained by the preliminary measurement, and determined by the first row sensor 132 Deterministically measure the height of part P.

The measurement unit 141 is an interface that receives signals from the encoder 114 and the first row sensor 132, and is a processing unit that converts the signals into signals (signals indicating true heights) that the height measurement unit 140 can easily process.

The height calculation unit 142 is a processing unit that calculates the height of the electronic part P based on a signal from the measurement unit 141 and the like.

The storage unit 146 holds a program for causing the altitude measurement unit 140 to perform each processing operation thereof. The storage unit 146 also includes an identifier for identifying each electronic part P, and stores values calculated by the height calculation unit 142 and the identifier of the corresponding electronic part P in association with each other.

Next, a method of measuring the height of the electronic part P using the mounter 100 structured as described above will be described.

FIG. 14 is a diagram showing a sequence of operations performed by the installer 100 .

First, the suction nozzle 111 sucks the electronic component P from the component supply unit 115 (S501). The transfer head 110 in this embodiment can pick up and hold up to 8 electronic components, and the following explanation is based on the assumption that a plurality of electronic components P are picked up and held.

Next, the scan control unit 144 moves the scan measurement unit 130 in the alignment direction of the suction nozzle unit 112 so that the scan measurement unit 130 scans the electronic part P held by the transfer head 110 ( S502 ).

Next, as shown in FIG. 15 , in the case where the first line sensor 132 responds to the scanning (S502) (“Yes” in S503 ), that is, when the first line sensor 132 detects that there is light from the projector 131 In the case of a blocked portion (YES in S503), the height calculation unit 142 preliminarily calculates the height of the electronic part P based on the signal from the first line sensor 132 and the signal from the encoder in the suction nozzle unit 112. (S506), and preliminarily save the calculated height in the storage unit 146.

More specifically, the measurement unit 141 receives a signal from the first line sensor 132 when light from the projector 131 is blocked, and sends a signal related to L2 shown in FIG. 15 to the height calculation unit 142 . In this case, the measurement unit 141 also receives a signal from the encoder, and sends a signal related to L1 shown in FIG. 15 to the height calculation unit 142 . Note that L1 is the amount by which the suction nozzle 111 is lowered from the initial position ("0" in FIG. . L2 is the distance from the vertical reference position ("C" in FIG. 15) of the first line sensor 132 to the lowest position of the range where light is blocked.

Note that the predetermined range included in the portions above and below the above-mentioned vertical reference position is a portion where the sensitivity of the first line sensor 132 is high.

The height calculation unit 142 obtains signals related to L1 and L2 from the measurement unit 141, and based on a predetermined distance L0 (6 mm in this embodiment) between the initial position 0 and the reference position C of the first line sensor 132, according to The equation PT (height of electronic part P)=L0-L1-L2 preliminarily calculates the height of electronic part P. Here, since L2 is a value obtained around both ends of the first row sensor 132, the precision of such measurement is low so that the value contains a large error.

The above-described processing operations are performed on all suction nozzles 111 equipped in the transfer head 110 .

On the other hand, in the case where there is no response in the first line sensor 132 even though the above-mentioned scanning is performed (NO in S503), the head control unit 143 further lowers only the sensor at the position where the sensor does not respond. The suction nozzle 111 (eg, additionally lowered by 1 mm) (S504).

The above processing (S502 to S505) is repeated until the heights of all electronic parts P held by the suction nozzle 111 are preliminarily calculated (S507).

As a result of the above processing, the preliminarily calculated heights of all electronic parts P are stored in the storage unit 146 (S506).

Note that FIG. 15 does not show a default state, but shows a state after the suction nozzle 111 is lowered to a certain extent. In addition, the suction nozzles 111 are lowered step by step because all the suction nozzles 111 are in a stable state at a certain level, so that the scanning measurement unit 130 scans all the electronic parts P from their sides and measures their heights sequentially. .

After preliminarily calculating the heights of all parts, the head control unit 143 controls each suction nozzle unit 112 so as to lower each suction nozzle 111 based on a signal from the encoder 114, thereby making each suction nozzle The lower surface of the electronic component P held by 111 is located at the reference position of the first row of sensors 132 (a position 6 mm lower than the initial position 0), as shown in FIG. 16 (S508).

Next, the scan control unit 144 controls the scan measurement unit 130 to move it while the measurement unit 141 measures the position of the lower surface of each electronic part P using the first line sensor 132 (S509).

Finally, the height calculation unit 142 deterministically measures the height of each electronic part P based on the value measured by the first row sensor 132 and the lowering amount of the suction nozzle 111 (signal from the encoder) (S510).

0)，在此处能够以最高精度确定性地测量电子部件P的高度，L2更为精确，并且仅包含较小的误差。注意，在图16中，电子部件P的下表面准确地位于基准位置C处，但其可以以由初步计算造成的误差偏离该基准位置C。The height of each electronic part P is measured using the same method as above, that is, the height of each electronic part P is deterministically calculated by the equation PT=L0-L1-L2. Here, since the lower surface of each electronic component P is located near the most sensitive reference position C of the first row of sensors (L2

0), where the height of the electronic component P can be measured deterministically with the highest accuracy, L2 is more precise and contains only small errors. Note that in FIG. 16 , the lower surface of the electronic part P is located exactly at the reference position C, but it may deviate from this reference position C by an error caused by preliminary calculation.

The above-described structure and processing allow the height of various electronic parts P from small parts to large parts to be measured based on the lowering amount of each suction nozzle 111 even with the first row of sensors 132 having a relatively small size. In addition, since the first row sensor 132 measures the height deterministically at its most sensitive part, a high precision value can be obtained.

The mounter 100 performs this height measurement, and the mounter 100 can use the value obtained by its measurement. In other words, since there is no human involvement, it is possible to save manpower and avoid human error.

Furthermore, since the transfer head 110 mounting the components performs this height measurement, it is also possible to mount already measured components on the board 120 . Therefore, there is no need for electronic parts P only for height measurement needs.

Since the transfer head 110 is equipped with the scanning measurement unit 130, the height of the part P can be measured while the transfer head 110 is moving, thus causing no time loss. Since the scanning measurement unit 130 is very small, not only can the reduction of the positioning accuracy of the transfer head 110 due to the height of the transfer head 110 be avoided, but also the small-sized scanning measurement unit 130 can measure the height of components with high precision.

Note that although the present embodiment has been described based on the assumption that the height measurement unit 140 is integrated with the mounter 100, the height measurement unit 140 is not necessarily integrated with the mounter 100, and may be integrated with the mounter 100 as a means for controlling the mounter 100. 100 separations.

Although the lower surface of the part P is located at the reference position C for deterministic measurement, the present invention is not limited to this positioning. The lower surface of the part P only needs to be located in the high-precision part of the first row sensor 132 (in the high-sensitivity range).

Furthermore, the height data of the electronic parts P in the parts library may be used instead of the values obtained by the preliminary measurement to perform deterministic measurement based on the height data. In other words, the height can be measured by placing the lower surface of the part P on the high-sensitivity portion of the first row sensor 132 .

In the preliminary measurement, the suction nozzle 111 does not have to be lowered step by step, but may be lowered at once based on the height data of the electronic parts P in the parts library.

(fifth embodiment)

Next, another embodiment of the present invention is described with reference to the drawings. In this embodiment, detailed operations for measuring minute components are described.

Here, micro parts are 0402, 0603 and 1005 chip parts, which have slight differences in dimensions such as length, width, height, and the like. Such minute parts also include 1608R and 2625R chip parts and other chip parts that do not have such a slight difference in size but have a height of 0.5 mm or less.

The configuration of this embodiment is the same as that of the above embodiments, and the height measurement method to step S507 in this embodiment are the same. Therefore, description thereof is omitted.

FIG. 17 is a flowchart showing processing for measuring the relationship between the lowering set value and the actual lowering amount of the suction nozzle 111 .

FIG. 18 is a side view showing the lowering amount of the measurement suction nozzle 111 .

As shown in the figure, the head control unit 143 lowers the suction nozzle 111 that does not hold the electronic component P (S801). More specifically, a set value (for example, 5.5 mm) is given to the head control unit 143 in advance so that the lower surface of the suction nozzle 111 is located at a predetermined distance (for example, 0.5 mm) above the reference position of the first line sensor 132 level, and the head control unit 143 controls the suction nozzle unit 112 so as to lower the suction nozzle 111 based on the signal from the encoder 114 .

Next, the scan control unit 144 scans while controlling the movement of the scan measurement unit 130 ( S802 ), and at the same time, the measurement unit 141 obtains the distance L2 from the reference position C to the lower surface of the suction nozzle 111 .

Next, the height calculation unit 142 subtracts the obtained distance L2 from the distance L0 (for example, 6 mm) between the initial position 0 and the reference position C to calculate the actual lowering amount L1 (S803).

As a result of the above calculation, the relationship between the above set value and the actual reduction amount L1 is obtained. In the present embodiment, since the obtained amount L1 has a slight deviation if the set value is assumed to be 5.5 mm, the repetition error is much smaller than the reduction error.

FIG. 19 is a flowchart showing the sequence of operations for measuring the height of the electronic part P in the present embodiment.

After the preliminary calculation of the height of the electronic part P is completed (YES in S507 in the above embodiment), it is judged whether the preliminary calculated height of the electronic part P is a predetermined value or more (S901). The predetermined value may be set to a value of, for example, 5 to 10 times the error between the actual lowering amount of the suction nozzle 111 and the set value. For example, if the error is 50 μm, the predetermined value is set to 0.5 mm.

Since this embodiment is for micro components, it is determined as "No" in S901. On the contrary, if it is a normal component instead of a micro component to be mounted, it is determined as "YES" in S901.

Note that although the judgment is made based on the comparison result between the preliminary measurement value and the predetermined value in S901, the judgment may be made according to the component type. For example, it is determined as "No" in S901 if a small part is to be mounted, and "YES" in S901 if a part other than a small part is to be mounted.

Next, in the case where the preliminarily calculated height is a predetermined value or more (YES in S901), as shown in FIG. 20 , the suction nozzle 111 is lowered so that the lower surface of the suction nozzle 111 is positioned at The position of the electronic component P is measured deterministically in (S902).

On the other hand, in the case where the preliminarily calculated height is smaller than the predetermined value (NO in S901), as shown in FIG. mm) to lower the electronic component P to the measurement position (S903).

Next, the scan measurement unit 130 is scanned ( S904 ) to obtain signals from the first row sensor 132 .

Finally, the height PT of the electronic component P is calculated (S905). Using the equation PT=L0-L1-L2, the height of the electronic part P is measured by the same method as in the above embodiment. In the case where the height of the electronic part P preliminarily measured is a predetermined value or less, this set value is not used as L1 in the above equation, but the height obtained by measuring without holding the electronic part P is used. The value obtained.

By adopting the above method, not only the error contained in L2 but also the error contained in L1 can be reduced when measuring the height of a relatively thin electronic part P. Therefore, an error contained in PT (measured height value) can be reduced.

Although only some embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the innovations and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention.

Industrial applicability

According to the present invention, the height of an electronic component can be measured with high precision. Therefore, the present invention can be used in a field in which an electronic component in an electronic component supply unit is sucked with a suction nozzle and mounted on a member to be mounted such as a board.

Claims (10)

1. A part height measuring method applied to a mounter equipped with a transfer head having a part suction-holding nozzle for transferring a part and mounting the part on a board, the The methods described include: a preliminary measuring step of lowering the part picked up and held by the suction nozzle, and measuring the height of the part in the vertical direction using the lowered amount of the suction nozzle and a signal output from a sensor for measuring the height of the part; a lowering step of lowering the part to within the high accuracy range of the sensor based on the height of the part measured in the preliminary measuring step; and A measuring step of measuring the height of the component using the sensor. 2. The component height measuring method according to claim 1, further comprising: The lower end position obtaining step lowers the suction nozzle of the unheld component and obtains information related to the vertical position of the lower end of the suction nozzle. 3. The component height measurement method according to one of claims 1 and 2, Wherein, the measuring step includes: when the height measured in the preliminary measuring step is less than a predetermined value, keeping the lower end of the suction nozzle at a predetermined position in the vertical direction, and deterministically measuring the height of the component . 4. The component height measurement method according to one of claims 1 and 2, Wherein, the measuring step includes: when the height measured in the preliminary measuring step is equal to or greater than a predetermined value, keeping the lower end of the part at a predetermined position in the vertical direction, and deterministically measuring the height of the part. 5. The component height measurement method according to one of claims 1 and 2, Wherein, after the suction nozzle is made stationary in the vertical direction, the sensor and the component are relatively moved on the horizontal plane, and one of the preliminary measuring step and the measuring step is performed. 6. The component height measuring method according to claim 1, wherein the delivery head has a plurality of suction nozzles and the sensor, and The measuring step includes measuring the height of each part picked up and held by the suction nozzle by causing the sensor to scan the part. 7. A component mounting method applied to a mounter equipped with a transfer head having a component suction-holding nozzle for transferring a component and mounting the component on a board, the Methods include: a preliminary measuring step of lowering the part picked up and held by the suction nozzle, and measuring the height of the part in the vertical direction using the lowered amount of the suction nozzle and a signal output from a sensor for measuring the height of the part; a lowering step of lowering the part to within the high accuracy range of the sensor based on the height of the part measured in the preliminary measuring step; a measuring step of measuring the height of the part using the sensor; and The mounting step, based on the measured height of the component, mounts the component to the board. 8. A component height measuring device for measuring the height of a component by applying the component height measuring device to a mounter equipped with a transfer head having a component suction-holding nozzle for transferring the part and mounting the part on a board, the apparatus comprising: a reduction amount detection unit for detecting the reduction amount of the suction nozzle; a head control unit for controlling the vertical movement of the suction nozzle; a height calculation unit for calculating a height of the component picked up and held by the suction nozzle based on the signal output from the sensor and the signal output from the lowering amount detection unit; a lowering unit for lowering the part into the high precision range of a sensor for measuring the height of the part; a global control unit for controlling the transfer head to preliminarily calculate the height of the part and then re-control the transfer head based on the preliminarily calculated height to lower the part within the high accuracy range of the sensor , measure and deterministically calculate the height of the part; and A measuring unit for measuring the height of the component using the sensor. 9. A mounter equipped with a transfer head having a component suction-holding nozzle for transferring a component and mounting the component to a board, the mounter comprising: a reduction amount detection unit for detecting the reduction amount of the suction nozzle; a head control unit for controlling the vertical movement of the suction nozzle; a height calculation unit for calculating a height of the component picked up and held by the suction nozzle based on the signal output from the sensor and the signal output from the lowering amount detection unit; a lowering unit for lowering the part into the high precision range of a sensor for measuring the height of the part; a global control unit for controlling the transfer head to preliminarily calculate the height of the part and then re-control the transfer head based on the preliminarily calculated height to lower the part within the high accuracy range of the sensor , measure and deterministically calculate the height of the part; and a measuring unit for measuring the height of the component using the sensor, Wherein, there are a plurality of said suction nozzles, the sensor detects the part picked up and held by the nozzle from the side of the part, and The lowering unit is used to adjust the heights of the plurality of suction nozzles independently of other suction nozzles, and each time the installation action is repeated, the height of each suction nozzle that repeatedly sucks and holds the component is adjusted to a certain level. constant height. 10. The installer of claim 9, Wherein, the lowering unit is used to selectively perform: the control for adjusting the height of each suction nozzle to a certain height; and the lower surface of the component sucked and held by each suction nozzle on the horizontal plane Alignment controls.

Images