JP6938328B2 - Part rotation angle detection method - Google Patents

Description

The present invention relates to a method for detecting a component rotation angle.

A component mounting machine is a device that mounts supplied components at a designated position on a board. In such a component mounting machine, when the component is mounted at a designated position on the substrate, the suction posture of the component sucked by the nozzle is imaged by a camera from below the component, and positioning processing and inspection processing are performed. Pattern matching is used when performing positioning processing and inspection processing. As pattern matching, the method of Patent Document 1 is known. For example, when the component to be processed has metal terminal portions on both sides of the resin main body portion, a clear brightness difference occurs between the main body portion and the terminal portion in the captured image. Therefore, the terminal portion can be recognized on the image. In the image, the matching rate between the reference pattern and the terminal portion is calculated while moving the reference pattern (template) corresponding to the size data of the terminal portion in the X direction, the Y direction, and the θ direction. Then, the position that gives the maximum matching rate is set as the component detection position. The X direction is the substrate transport direction (horizontal direction), the Y direction is the front-rear direction, and the θ direction is the rotation direction. Normally, in pattern matching, when the reference pattern is moved in the X and Y directions, it is moved by a predetermined pitch length, and when it is moved in the θ direction, it is moved by a predetermined pitch angle.

Japanese Unexamined Patent Publication No. 2011-91181

However, the moving distance of the terminal portion before and after rotating by a predetermined pitch angle increases as the distance from the center of rotation to the terminal portion increases. Therefore, when the part to be processed is a long part, if the length in the longitudinal direction is long, the part may not be detected by pattern matching. That is, even if the reference pattern is moved by a predetermined pitch angle in the θ direction, the matching rate does not become a large value at any position, and the component may not be detected. On the other hand, when the predetermined pitch angle is set to a small angle in consideration of this point, the number of times the matching rate is calculated is unnecessarily increased for a short component having a short distance from the center of rotation to the terminal portion, and the processing time is increased. There was a problem that the number increased.

This disclosure is made to solve such a problem, and while the rotation angle can be reliably detected even if the part shown in the image is a long part or a large part, a short part or a small part can be detected. The main purpose is to be able to detect the rotation angle in a short time even for the parts of.

The component rotation angle detection method of the present disclosure is
In detecting the rotation angle of the target part shown in the image, the amount of coincidence between the mark portion of the template and the mark portion of the target part is determined while rotating the template corresponding to the target part on the image for each pitch angle. It is a component rotation angle detection method that obtains and detects the rotation angle of the target component based on the matching amount and the rotation angle of the template.
The pitch angle is set so that the longer the distance between the rotation center of the template and the mark portion of the template when rotating the template, the smaller the pitch angle.
It is a thing.

In this component rotation angle detection method, the pitch angle is set so that the longer the distance between the rotation center of the template and the mark portion of the template when rotating the template, the smaller the pitch angle. Therefore, even if the parts shown in the image are long parts or large parts, the rotation angle can be reliably detected. Further, the pitch angle is set so that the shorter the distance between the rotation center of the template and the mark portion of the template, the larger the pitch angle. Therefore, the rotation angle can be detected in a short time even for a short part or a small part.

The perspective view which shows the schematic structure of the component mounting machine 30. Perspective view of the reel 41. Explanatory drawing of a short part 100. Explanatory drawing of template 110 corresponding to a short part 100. Explanatory drawing of X direction search. Explanatory drawing of Y direction search. Explanatory drawing of θ direction search. Explanatory drawing which shows the state of detecting the posture of the part 100. Explanatory drawing of a long part 200. Explanatory drawing of template 210 corresponding to a long part 200. Explanatory drawing which shows the state before and after rotating the template 210 by the pitch angle α. Explanatory drawing which shows the state before and after rotating the template T corresponding to a component P by a pitch angle α. A partially enlarged view of FIG. Explanatory drawing which shows the pitch angle α of a long part 200. It is explanatory drawing which shows the pitch angle α of a short part 100.

A preferred embodiment for explaining the component rotation angle detection method of the present disclosure will be described below with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of a component mounting machine 30, and FIG. 2 is a perspective view of a reel 41. The left-right direction (X direction), the front-back direction (Y direction), and the up-down direction (Z direction) are as shown in FIGS. 1 and 2.

As shown in FIG. 1, the component mounting machine 30 includes a component supply device 40, a board transfer device 45, an XY robot 50, a mounting head 60, a parts camera 48, a mark camera 49, and a controller 70. ing.

A plurality of component supply devices 40 are provided on the front side of the component mounting machine 30 so as to be arranged in the left-right direction (X direction). As shown in FIG. 2, the component supply device 40 is configured as a tape feeder that pulls out a tape 42 containing components P at predetermined intervals from a reel 41 and feeds the tape 42 at a predetermined pitch. The tape 42 wound around the reel 41 is formed so that a plurality of recesses 42a are arranged along the longitudinal direction of the tape 42. A component P is housed in each recess 42a. These parts P are protected by a film 43 that covers the surface of the tape 42. The tape 42 has a sprocket hole 42b formed along the longitudinal direction. The tape 42 is fed at a predetermined pitch by fitting the teeth of the sprocket (not shown) of the component supply device 40 into the sprocket hole 42b and rotating the sprocket hole 42b by a predetermined amount. The film 43 is peeled off from the component P that has reached the predetermined component supply position F.

The substrate transfer device 45 has a pair of conveyor belts 46, 46 (only one is shown in FIG. 1) which are provided at intervals in the front-rear direction and are bridged in the left-right direction. When the substrate 32 is conveyed by the conveyor belts 46, 46 in the direction of the arrow of the alternate long and short dash line in FIG. 1 and reaches a predetermined intake position, the substrate 32 is supported by a large number of support pins 47 erected on the back surface side.

The XY robot 50 includes an X-axis slider 52 and a Y-axis slider 54. The X-axis slider 52 can move along the X-axis guide rails 51 and 51 provided in the left-right direction (X direction) on the front surface of the Y-axis slider 54. The Y-axis slider 54 can move along the Y-axis guide rails 53 and 53 provided in the front-rear direction (Y direction).

The mounting head 60 is attached to the X-axis slider 52. The mounting head 60 is provided with a nozzle 64 on the lower surface thereof. The nozzle 64 attracts the component P when a negative pressure is supplied, and releases the component P when an atmospheric pressure or a positive pressure is supplied.

The parts camera 48 is provided between the parts supply device 40 and the board transfer device 45. The parts camera 48 takes an image of the parts P attracted to the nozzle 64 from below.

The mark camera 49 is attached to the lower surface of the X-axis slider 52. The mark camera 49 takes an image of the component P mounted on the substrate 32 supported by, for example, the support pin 47.

The controller 70 is configured as a microprocessor centered on a CPU. A position detection signal from the XY robot 50, an image signal from the parts camera 48, an image signal from the mark camera 49, and the like are input to the controller 70. Further, from the controller 70, a control signal to the component supply device 40, a control signal to the board transfer device 45, a control signal to the XY robot 50, a control signal to the mounting head 60, a control signal to the parts camera 48, and a mark. A control signal or the like to the camera 49 is output.

Next, the operation when the component mounting machine 30 performs the component mounting process will be described. The controller 70 controls each part of the component mounting machine 30 based on a production program received from a management device (not shown) to produce a board 32 on which a plurality of components P are mounted. Specifically, the controller 70 controls the XY robot 50 so that the nozzle 64 faces the component P sent to the component supply position F (see FIG. 1) by the component supply device 40. Subsequently, the controller 70 controls the pressure of the nozzle 64 so that the component P at the component supply position F is attracted to the nozzle 64. Subsequently, the controller 70 controls the XY robot 50 and the parts camera 48 so as to capture an image of the component P attracted to the nozzle 64. Then, the controller 70 recognizes the posture of the component P by processing the obtained image of the component P with a template obtained from the shape data (including the component size data) of the component P. Subsequently, the controller 70 controls the XY robot 50 so that the component P is arranged directly above the designated position of the board 32 in consideration of the posture of the component P, and the nozzle 64 releases the component P. Control the pressure. The controller 70 repeatedly executes such a component mounting process to mount a predetermined number and types of components P on the substrate 32. A mounting line is formed by arranging a plurality of such component mounting machines 30 in the left-right direction. When the board 32 is transported from the most upstream component mounting machine 30 of one mounting line to the most downstream component mounting machine 30, all predetermined components P are mounted on the board 32. There is. Many such mounting lines are provided in component mounting factories.

Next, the process of recognizing the posture of the component P will be described below. Here, as the component P, as shown in FIG. 3, a rectangular parallelepiped resin main body 102 and a rectangular metal main body 102 provided along the long sides facing each other are provided three by three. An example is a component 100 having an electrode portion 104. In the image obtained when the component 100 adsorbed on the nozzle 64 is imaged from below by the component camera 48, a clear brightness difference occurs between the main body portion 102 and the electrode portion 104. Therefore, for example, the image can be binarized to separate the electrode portion 104 into white and the portion other than the electrode portion 104 into black. As shown in FIG. 4, the template 110 corresponding to the component 100 has an electrode detection region 114 provided corresponding to each electrode portion 104 of the component 100. The electrode detection region 114 is formed in the rectangular electrode portion 104 in anticipation of a predetermined margin. The margin is set so as not to include the adjacent electrode portion 104.

In recognizing the posture of the component 100, the X-direction search, the Y-direction search, and the θ-direction search are executed on the image obtained by capturing the component 100 using the template 110. For example, as shown in FIG. 5, the X-direction search is performed by moving the template 110 from the position indicated by the dotted line to the position indicated by the solid line in the X direction (here, from left to right) by a predetermined length pitch. For example, as shown in FIG. 6, the Y-direction search is performed by moving the template 110 from the position indicated by the dotted line to the position indicated by the solid line in the Y direction (here, from top to bottom) by a predetermined length pitch. As shown in FIG. 7, in the θ direction search, the template 110 is rotated counterclockwise by a pitch angle α from the position shown by the dotted line to the position shown by the solid line with the center of the template 110 as the center of rotation. It is done by rotating it to. By performing the X-direction search, the Y-direction search, and the θ-direction search in combination in this way, as shown in FIG. 8, each electrode detection region 114 of the template 110 and each electrode portion 104 of the component 100 (high-brightness portion). ) Is obtained, and the posture of the component 100 is detected based on the matching amount and the posture of the template 110. For example, the posture of the template 110 when the matching amount is maximized, that is, the XY coordinates (x, y) and the rotation angle θ of the center of the template 110 are detected as the posture of the component 100. FIG. 8A shows an image when the component 100 is imaged by the component camera 48. FIG. 8B shows a template 110 when the component 100 (dashed line) is detected from the image.

Here, the θ-direction search will be described in detail by taking the long component 200 shown in FIG. 9 as an example. The component 200 has a rectangular parallelepiped and resin main body portion 202, and a rectangular metal electrode portion 204 provided on each of the main body portions 202 on long sides facing each other. The electrode portion 204 on the outermost side of the component 200 from the center of rotation (the electrode portion 204 on the upper right in FIG. 9) is designated as the mark portion 200M of the component 200. As shown in FIG. 10, the template 210 corresponding to the component 200 has a shape in which 13 rows of electrode detection regions 214 arranged in the X direction are provided in two stages at intervals in the Y direction. The electrode detection region 214 on the outermost side of the template 210 (the electrode detection region 214 on the upper right in FIG. 10) is designated as the mark portion 210M of the template 210. For the rotation angle θ of the component 200, the matching amount between the electrode detection region 214 of the template 210 and the electrode portion 204 of the component 200 is obtained while rotating the template 210 by the pitch angle α on the image of the component 200, and the matching amount is obtained. And the rotation angle θ of the component 200 is detected based on the rotation angle of the template 210. For example, the rotation angle of the template 210 when the matching amount is maximized may be the rotation angle θ of the component 200.

FIG. 11 is an explanatory diagram showing a state before and after rotating the template 210 by a pitch angle α. In the θ-direction search, the template 210 is rotated by the pitch angle α to search for a position where the mark portion 210M of the template 210 coincides with the mark portion 200M of the component 200 as much as possible. If the pitch angle α is too large when searching in the θ direction, the position of the mark portion 210M before rotating the template 210 by the pitch angle α (see the dotted line) and the position of the mark portion 210M after the rotation (see the solid line). A large undetected region is generated between the and, as shown in the partially enlarged view of FIG. If the mark portion 200M of the component 200 is located in the undetected region, the amount of coincidence between the mark portion 210M of the template 210 and the mark portion 200M of the component 200 is equal to that before or after the template 210 is rotated by the pitch angle α. It may be insufficient and the rotation angle θ may not be specified. In order to prevent this, the pitch angle α may be reduced, but if this is done, for example, in the short component 100 as shown in FIG. 3, the number of processings is unnecessarily increased, and the processing time required for the θ-direction search is increased. Problem arises. Therefore, in the present embodiment, the pitch angle α is not uniformly the same for all parts, and is set to be smaller as the distance between the rotation center of the template and the mark portion of the template when rotating the template is longer. ing.

The method of setting the pitch angle α will be described with reference to FIGS. 12 and 13. FIG. 12 is an explanatory view showing a state before and after rotating the template T corresponding to the component P by the pitch angle α, and FIG. 13 is a partially enlarged view of FIG. The template T is created based on the shape data of the component P (including the size / center coordinates of the component, the size / center coordinates of the electrode portion, and the like). Of the electrode portions of the component P, the one located at the position farthest from the center of rotation is designated as the mark portion PM of the component P. The electrode detection region of the template T located at the position farthest from the center of rotation is designated as the mark portion TM of the template T. The electrode detection region of the template T is a square region having a side length of h. The XY coordinates of the center of the mark portion TM of the template T are (x1, y1), the length (radius) from the rotation center O of the template T to the center of the mark portion TM of the template T is r, and the template T is the rotation center O. Let L be the moving distance of the center of the mark portion TM of the template T before and after rotating around by the pitch angle α. The rotation center O of the template T is the center of the component P. In order to prevent an undetected region from occurring between the mark portion TM (electrode detection region) before and after the rotation by the pitch angle α, the movement distance L may be set so that the mark portion TM before and after the rotation overlaps. .. Here, the moving distance L is set to 1/2 of the length h of the electrode detection region in the Y direction. It is not necessary to limit the number to 1/2, and for example, it may be appropriately set to a value within the range of 1/4 to 3/4 (preferably 3/4 to 5/8). The pitch angle α [rad] can be approximated by the equation (1).

Assuming that the size of the electrode detection region is constant regardless of the size of the component P, the larger the radius r, the smaller the pitch angle α. Generally, the larger the radius r, the longer the component in the longitudinal direction or the larger the component. FIG. 14 is an explanatory diagram showing the pitch angle α of the long component 200, and FIG. 15 is an explanatory diagram showing the pitch angle α of the short component 100. Both pitch angles α are obtained by Eq. (1). As shown in FIG. 14, the pitch angle α of the template 210 corresponding to the long component 200 becomes relatively small, and the rotation angle θ can be reliably detected in the θ direction search of the component 200. On the other hand, as shown in FIG. 15, although the pitch angle α of the template 110 corresponding to the short component 100 is relatively large, the rotation angle θ can be reliably detected, and the number of processing for the θ direction search may be unnecessarily increased. No.

The controller 70 of the component mounting machine 30 sets the pitch angle α. The controller 70 is accessibly connected to a storage device in which the shape data of each component P mounted on the board 32 is stored. The controller 70 reads the shape data of the target component for which the θ direction search is performed from the storage device, creates a template corresponding to the target component, and sets the pitch angle α using the above equation (1). The controller 70 searches in the θ direction using the pitch angle α, and obtains the rotation angle θ of the target component.

In the θ-direction search (component rotation angle detection method) described above, the pitch angle α becomes smaller as the distance (radius r) between the rotation center O when rotating the template T and the mark portion TM of the template T becomes longer. Is set. Therefore, even if the component P captured in the image captured by the parts camera 48 is a long component 200 or a large component, the rotation angle θ can be reliably detected. Further, the pitch angle α is set so that the shorter the distance (radius r) between the rotation center O of the template T and the mark portion TM of the template T, the larger the pitch angle α. Therefore, even if the short component 100 or the small component is used, the time required to detect the rotation angle θ does not become unnecessarily long, and the rotation angle θ can be detected in a short time.

Further, the pitch angle α includes the movement distance L of the mark portion TM of the template T before and after rotating the template T by the pitch angle α, and the distance (radius r) from the rotation center O to the mark portion TM of the template T. Calculated using trigonometric functions (see equation (1)). Therefore, the pitch angle α can be calculated relatively easily.

Further, the moving distance L is set so that the mark portion TM of the template T set to include the mark portion PM of the component P overlaps by a predetermined amount before and after rotating the template T by the pitch angle α. As a result, the undetected region of the mark portion TM does not occur before and after rotating the template T by the pitch angle α, so that the rotation angle θ can be detected more reliably.

Furthermore, since the mark portion PM of the component P is a metal electrode portion and the main body portion surrounding the mark portion PM of the component P is made of resin, the mark portion PM of the component P is shown in the image. A clear difference in brightness occurs between the portion PM and its surroundings. As a result, the mark portion PM of the component P can be clearly recognized on the image.

Further, since the mark portion PM of the component P is the electrode portion located at the position farthest from the rotation center O among the plurality of metal electrode portions arranged along the longitudinal direction of the component P, the pitch angle α is set to be higher. It can be calculated appropriately.

It goes without saying that the present invention is not limited to the above-described embodiment, and can be implemented in various aspects as long as it belongs to the technical scope of the present invention.

For example, in the above-described embodiment, the pitch angle α is calculated using the equation (1), but the equation (2) may be used instead of the equation (1). Equation (2) can be easily obtained from FIG.

In the above-described embodiment, the electrode detection region is a region in which a margin is expected in the electrode portion, but the electrode detection region may be a region having the same size as the electrode portion.

In the above-described embodiment, the pitch angle α is set to be continuously reduced as the radius r becomes longer, but may be gradually reduced as the radius r becomes longer. For example, when the pitch angle α after the decimal point is rounded off to an integer, the relationship between the radius r and the pitch angle α becomes stepwise, and becomes stepwise as the radius r becomes longer. Alternatively, when the radius r falls within the first numerical range, the pitch angle α is set to α1, and when the radius r falls within the second numerical range (> the first numerical range), the pitch angle α is set to α2 (<α1). When the radius r falls within the third numerical range (> the second numerical range), the pitch angle α may be set to α3 (<α2).

In the above-described embodiment, as the component P, a component P having a rectangular electrode portion 104 provided on the main body portion 102 is exemplified, but the shape of the electrode portion 104 is not limited to a rectangle, and is, for example, a circle. Or oval. Further, as the component P, a component P provided so that a metal lead portion protrudes from the resin main body portion may be used.

In the above-described embodiment, the case where the component P attracted to the nozzle 64 is searched in the θ direction using the template on the image captured by the parts camera 48 is illustrated, but the component P mounted on the substrate 32 is a mark camera. The θ-direction search may be performed using the template on the image captured by 49.

In the above-described embodiment, the controller 70 of the component mounting machine 30 sets the pitch angle α, but the pitch angle α is set by a pitch angle setting device (computer device) different from the component mounting machine 30. You may. The pitch angle setting device is connected to the storage device described above so as to be accessible. The pitch angle setting device sets the pitch angle α of the template for each component in advance using the equation (1) based on the shape data, and stores the pitch angle α in the storage device in association with the component. The controller 70 of the component mounting machine 30 reads the pitch angle α corresponding to the target component for which the θ direction search is performed from the storage device, performs the θ direction search using the pitch angle α, and obtains the rotation angle θ of the target component.

The component rotation angle detection method of the present disclosure may be configured as follows.

In the component rotation angle detection method of the present disclosure, the pitch angle is the moving distance of the mark portion of the template before and after rotating the template by the pitch angle and the distance from the rotation center to the mark portion of the template. It may be calculated by using the trigonometric function including. In this way, the pitch angle can be calculated relatively easily.

In the component rotation angle detection method of the present disclosure, the movement distance is set so that the mark portion detection region set to include the mark portion of the template overlaps by a predetermined amount before and after rotating the template by the pitch angle. It may have been done. By doing so, the undetected region of the mark portion is not generated before and after the rotation by the pitch angle, so that the rotation angle can be detected more reliably. Here, the "predetermined amount" is not particularly limited, but for example, it is preferably set in the range of 1/4 to 3/4 of the mark site detection area, and 3/8 to 5/8 of the mark site detection area. It is more preferable to set in the range of.

In the component rotation angle detection method of the present disclosure, the mark portion of the target component may be made of metal, and the periphery of the mark portion of the target component may be made of resin. By doing so, in the image in which the target component is captured, a clear difference in brightness is generated between the mark portion and its surroundings, so that the mark portion can be clearly recognized on the image.

In the component rotation angle detection method of the present disclosure, the mark portion of the target component may be a metal portion located at the position farthest from the rotation center among a plurality of metal portions arranged along the longitudinal direction of the target component. .. In this way, the pitch angle can be obtained more appropriately.

30 parts mounting machine, 32 boards, 40 parts supply device, 41 reels, 42 tapes, 42a recesses, 42b sprocket holes, 43 films, 45 board transfer devices, 46 conveyor belts, 47 support pins, 48 parts cameras, 49 mark cameras, 50 XY robot, 51 X-axis guide rail, 52 X-axis slider, 53 Y-axis guide rail, 54 Y-axis slider, 60 mounting head, 64 nozzles, 70 controller, 100 parts, 102 main body, 104 electrode, 110 template, 114 Electrode detection area, 200 parts, 200M mark part, 202 main body part, 204 electrode part, 210 template, 210M mark part, 214 electrode detection area, F part supply position, P part, PM mark part, T template, TM mark part ..

Claims (5)

In detecting the rotation angle of the target part shown in the image, the amount of coincidence between the mark portion of the template and the mark portion of the target part is determined while rotating the template corresponding to the target part on the image for each pitch angle. It is a component rotation angle detection method that obtains and detects the rotation angle of the target component based on the matching amount and the rotation angle of the template.
The pitch angle is set so that the longer the distance between the rotation center of the template and the mark portion of the template when rotating the template, the smaller the pitch angle.
Part rotation angle detection method. The pitch angle is calculated using a trigonometric function including the moving distance of the mark portion of the template before and after rotating the template by the pitch angle and the distance from the rotation center to the mark portion of the template.
The component rotation angle detection method according to claim 1. The movement distance is set so that the mark portion detection region set to include the mark portion of the template overlaps by a predetermined amount before and after rotating the template by the pitch angle.
The component rotation angle detecting method according to claim 2. The mark portion of the target part is made of metal, and the periphery of the mark part of the target part is made of resin.
The component rotation angle detection method according to any one of claims 1 to 3. The mark portion of the target component is a metal portion located at the position farthest from the center of rotation among a plurality of metal portions arranged along the longitudinal direction of the target component.
The component rotation angle detection method according to any one of claims 1 to 4.

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