Parts position detection device

Abstract

A component position detection device (400) for accurately measuring the position of a component (P) that has been suction-attached to a suction-attachment nozzle (20) comprises: a first lighting (210) that emits light of a first frequency from the tip-end side toward the rear-end side of the suction-attachment nozzle (20); a reflecting plate (230) that reflects the light emitted by the first lighting (210) from the rear-end side toward the front-end side of the suction-attachment nozzle (20); and a first camera (220) that receives the light of the first frequency that has been reflected by the reflecting plate (230). The reflecting plate (230) is coated with, or contains, a light-reflective pigment that reflects the light of the first frequency. Alternatively, a multilayer film in which each layer has a thickness of an integer multiple of 1 / 4 the wavelength of the light of the first lighting (210) is deposited on the reflecting plate (230).

Description

[Technical Field]

[0001] The present invention relates to a component position detection device that detects the position of a component picked up by a suction nozzle in a component mounting device. [Background technology]

[0002] Mounters that mount components onto boards are equipped with a nozzle that picks up the components or places the picked-up components on the board (hereafter referred to as a suction nozzle). Negative pressure is generated inside the suction nozzle to suck the component onto the tip, and the suction nozzle is then moved above the board and the negative pressure is released to place the component on the board.

[0003] When a component is picked up onto the tip of the suction nozzle in this way, it is very important to check in advance whether the component is in the desired position and orientation. If the component picked up by the tip of the suction nozzle is not in the desired position or orientation, it may not be possible to place the component accurately on the pattern on the board where it should be placed, or the component may fall over.

[0004] Patent Document 1 proposes an electronic component mounting device that is equipped with a mechanism for detecting the position of a component picked up at the tip of a suction nozzle.

[0005] The electronic component mounting device disclosed in Patent Document 1 includes a transfer head that picks up electronic components from a parts feeder and places them on the board, a camera located in the path of movement of the electronic components held by the transfer head and that recognizes the electronic components, a nozzle provided on the transfer head that picks up the electronic components, a reflector located behind the electronic components picked up by the nozzle, and a light source unit that irradiates light toward the reflector, the reflector having a mirror-like reflective surface that reflects the illumination light from the light source unit toward the camera, and the surface of the reflective surface is covered with a protective film that consists of a near-infrared transmission filter and a hard coating that covers the surface of the near-infrared transmission filter. By irradiating the back of the component with light reflected from the reflector, the image of the electronic component can be captured by the camera without generating a shadow from the suction nozzle, allowing the position of the component to be estimated with high recognition accuracy. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3644212 Summary of the Invention [Problem to be solved by the invention]

[0007] The Patent Document 1 discloses that the surface of the reflector should be covered with a protective film consisting of a near-infrared transmission filter and a hard coating that covers the surface of this near-infrared transmission filter. This allows a sufficient amount of reflected light to illuminate electronic components, and also protects the reflective surface from dirt and wear, allowing for long-term use.

[0008] The near-infrared transmission filter is installed to transmit infrared light emitted from a light source and then reflect the infrared light with a mirror-like reflector. It also serves the purpose of preventing visible light from being reflected by the reflector, taking advantage of the fact that visible light emitted from other light sources is hardly transmitted through the near-infrared transmission filter.

[0009] However, the inventors' experiments revealed that in order to obtain sufficient reflected light from a reflector that has been subjected to a mirror finish such as aluminum deposition and is covered with a near-infrared transmission filter, as disclosed in Patent Document 1, a strong light source is required. This is because the near-infrared transmission filter absorbs light and the reflection of light relies solely on the mirror surface. It was also found that visible light components are included in the reflected light due to the reflection of visible light by the near-infrared transmission filter and the protective film.

[0010] These findings revealed that position detection using infrared light requires a lot of power, and that position detection using visible light has the problem that high accuracy cannot be achieved due to the light reflected from the reflector. [Means for solving the problem]

[0011] The device of the present invention is a device for detecting the position of a component picked up by a suction nozzle of a component mounting machine, and is equipped with a first light-emitting unit that emits light of a first frequency from the tip side toward the rear end side of the suction nozzle, a reflecting unit that reflects the light emitted by the first light-emitting unit from the rear end side toward the front end side of the suction nozzle, and a first light-receiving unit that receives the light of the first frequency reflected by the reflecting unit, and the reflecting unit contains a light-reflecting pigment that reflects light of the first frequency.

[0012] Furthermore, in the device according to the present invention, the first light-emitting unit may emit coherent light, the reflecting unit may have an inclined portion, and the first light-receiving unit may be installed on the optical path of light emitted by the first light-emitting unit and reflected by the inclined portion, and on the opposite side of the suction nozzle across the component.

[0013] In addition, the device of the present invention is provided with a second light-emitting unit that is installed on the opposite side of the suction nozzle across the component and that emits light of a second frequency from the front end side toward the rear end side of the suction nozzle, and a second light-receiving unit that receives light that is reflected by the component from the light emitted by the second light-emitting unit, and the first frequency and the second frequency may be different values.

[0014] In the device according to the present invention, the reflectance of the light-reflecting pigment to light of the first frequency may be greater than the reflectance of the light-reflecting pigment to light of the second frequency.

[0015] In the device according to the present invention, the reflectance of the light reflecting pigment to light of the first frequency may be four or more times greater than the reflectance of the light reflecting pigment to light of the second frequency.

[0016] In the device according to the present invention, the reflecting portion may be formed from a resin compounded with a light-reflecting pigment.

[0017] In the device according to the present invention, the reflecting portion may be coated with a light-reflecting pigment.

[0018] In the device according to the present invention, the suction nozzle and the reflecting portion may be integrally formed from a resin material.

[0019] In addition, the device of the present invention is a device for detecting the position of a component picked up by a suction nozzle of a component mounter, and is equipped with a first light-emitting unit that emits light of a first frequency from the tip side toward the rear end side of the suction nozzle, a reflecting unit that reflects the light emitted by the first light-emitting unit from the rear end side toward the front end side of the suction nozzle, and a first light-receiving unit that receives the light of the first frequency reflected by the reflecting unit, wherein the reflecting unit has a multilayer film in which materials with different refractive indices are stacked, and the thickness of each film in the multilayer film is an integer multiple of one-fourth the wavelength of the light of the first frequency.

[0020] In the device according to the present invention, the multilayer film may be a film made of materials having different refractive indices that are periodically laminated. [Effects of the Invention]

[0021] According to the device of the present invention, the light from the first light projecting unit is strongly reflected by the reflector, so that the position of the component can be estimated with sufficient accuracy even if the power supplied to the first light source is small.

[0022] Furthermore, since the light from the second light-projecting unit is hardly reflected by the reflector, the light from the second light-projecting unit reflected by the reflector is not reflected on the second light-receiving unit, making it possible to accurately estimate the position of the component.

[0023] Furthermore, by molding the reflecting portion from a resin compounded with a light-reflecting pigment, the components of the device according to the present invention can be produced inexpensively, leading to reduced manufacturing costs. It also becomes easy to form the reflecting portion integrally with the suction nozzle. This makes the components cheaper and easier to handle.

[0024] Furthermore, by using a method of applying a light-reflecting pigment to the reflective portion, the components of the device according to the present invention can be manufactured using a simple method. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a configuration diagram of a component mounting device equipped with a suction nozzle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of a suction nozzle according to an embodiment of the present invention. [Figure 3] FIG. 3 is a graph showing the correlation between volume resistance and discharge completion time. [Figure 4] FIG. 4 is a cross-sectional view of a suction nozzle according to an embodiment of the present invention. [Figure 5] FIG. 5 is a cross-sectional view of a suction nozzle according to an embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing the structure of a mold for a suction nozzle and a reflector according to an embodiment of the present invention. [Figure 7] FIG. 7 is a graph showing the characteristics of near-infrared reflective pigments. [Figure 8] FIG. 8 is a cross-sectional view of a suction nozzle according to an embodiment of the present invention. [Figure 9] FIG. 9 is a graph showing the characteristics of the dielectric multilayer film. [Figure 10] FIG. 10 is a diagram showing an example of an image captured by a camera. DETAILED DESCRIPTION OF THE INVENTION

[0026] The following describes in detail an embodiment of the present invention with reference to the drawings. The configurations, shapes, etc. described below are examples for the purpose of explanation, and can be modified as appropriate depending on the specifications of the suction nozzle, etc. In the following, corresponding elements in all drawings are given the same reference numerals, and duplicated explanations will be omitted.

[0027] (Embodiment) (1. Composition) (1.1 Overall Structure) The configuration of the component mounting apparatus 1 will be described with reference to Fig. 1. In Fig. 1 and in some parts described below, two axial directions that are orthogonal to each other in a horizontal plane are shown as the X direction of the board transport direction (the direction perpendicular to the paper surface in Fig. 1) and the Y direction that is orthogonal to the board transport direction (the left-right direction in Fig. 1). Also, the Z direction (the up-down direction in Fig. 1) is shown as the height direction that is orthogonal to the horizontal plane.

[0028] The component mounting apparatus 1 has the function of manufacturing a mounted board by mounting components on a board. A board transport mechanism 2 provided on the upper surface of a base 1a transports a board 3 in the X direction and positions and holds it. Above the board transport mechanism 2, a mounting head 5 is installed which is moved in horizontal directions (X direction and Y direction) by a head moving mechanism 4. The component mounting apparatus 1 is also called a component mounter.

[0029] The mounting head 5 is equipped with multiple nozzle units 6. Each nozzle unit 6 has a nozzle shaft 7 extending downward from a mechanism section 6a. A suction nozzle 20 is detachably attached to a nozzle holder 8 connected to the lower end of the nozzle shaft 7. The suction nozzle 20 has the function of holding a component P by using a suction force generated by a negative pressure generating source 17 (see FIG. 2). Each mechanism section 6a has a built-in lifting mechanism that raises and lowers the nozzle shaft 7. By driving this lifting mechanism, the suction nozzles 20 attached to the nozzle holder 8 are raised and lowered individually. Here, the mounting head 5 is equipped with multiple suction nozzles 20 (for example, four in the X direction and two in the Y direction, for a total of eight). In other words, the mounting head 5 can pick up multiple components P at once and transfer and mount them on the board 3.

[0030] 1, a plurality of tape feeders 10 are mounted side by side in the X direction on the top of a carriage 9 coupled to a base 1a on the side of the board transport mechanism 2. Below the tape feeders 10 on the carriage 9, a component reel 12 is held, on which a carrier tape 11 storing components P is wound and stored. The tape feeder 10 transports the carrier tape 11 pulled out from the component reel 12 in the tape feed direction, and supplies the components P to the component take-out position. The mounting head 5 takes out the components P supplied to the component take-out position, and transfers and mounts them to the mounting position for the board 3 held by the board transport mechanism 2. A freely openable main body cover 13 is provided above the carriage 9 to prevent workers from touching the mounting head 5 and other components while they are moving.

[0031] Because peeling charge occurs when the component P is peeled off the carrier tape 11, the component P may be charged to 400 V or more when it is removed from the tape feeder 10. Meanwhile, the board 3 and suction nozzle 20 are connected to ground and are essentially at 0 V potential. The moment the component P charged to 400 V or more comes into contact with the suction nozzle 20 connected to ground, the component P is connected to ground, and charge flows through the suction nozzle 20. This can cause electrostatic damage to the component P. Note that "moment" here refers to a time of approximately 0 to 0.00015 msec.

[0032] Furthermore, if component P is transferred and mounted on a grounded board 3 while still charged to 400V or more, the charge in component P will flow to board 3 and other components mounted there the moment it is mounted. This can cause electrostatic damage to component P and other components mounted on board 3.

[0033] The time it takes for the suction nozzle 20 to pick up the component P from the tape feeder 10 and transfer and mount it on the board 3 is approximately 0.6 seconds or more. Therefore, it is considered preferable to set the time it takes for the charge of the component P to fall to ground via the suction nozzle 20 to 1 msec to 100 msec.

[0034] Furthermore, the suction nozzle 20 is repeatedly subjected to a compressive load of 0.01 to 0.5 N in the Z direction when picking up the component P and when mounting it on the board 3, and typically needs to be durable enough to be able to be used continuously for more than 1 million times. Here, "continuously" means that the component can be stably picked up and mounted on the board without the need for equipment maintenance such as cleaning resin debris from the nozzle tip or replacing the nozzle.

[0035] (1.2 Suction nozzle configuration) In this embodiment, the suction nozzle 20 is made of molded resin.

[0036] Conventional component mounting machines sometimes use metal suction nozzles for the component mounting suction nozzle 20. However, this can cause dents or other scratches on the components. For this reason, to prevent scratches on the components, a shock-absorbing spring is often attached to the mounting part of the component mounting suction nozzle, or the tip of the component mounting suction nozzle is often covered with ceramic. However, even with these measures, there are times when these shock-absorbing mechanisms alone are not enough to absorb the impact when mounting components with a component mounting machine, and each time this occurs, the operator must adjust the height of the component or the pushing height of the component mounting suction nozzle to reduce the impact force on the component.

[0037] Furthermore, when the tip of a component mounting suction nozzle is covered with ceramic, the porous nature of ceramic makes it susceptible to solder and other contaminants, necessitating frequent cleaning. The ceramic surface can be polished to reduce the adhesion of such contaminants, but this requires a lot of processing time and tends to result in an expensive component.

[0038] Furthermore, ceramics are prone to breaking and chipping, which can cause poor suction. Furthermore, because ceramics are an insulator, if chipped pieces fall onto a substrate, they can destroy the circuitry depending on where they land. Furthermore, attaching ceramic to the nozzle tip requires very high manufacturing and component costs, which increases the manufacturing cost of the product.

[0039] For this reason, in order to reduce costs and ease the burden on operators, a resin component mounting suction nozzle has been proposed, as in Patent Document No. 5746763. However, because the suction nozzle described in that patent document is made of a low-resistance conductive resin, the charge on the component that has been charged before pickup is instantly transferred to the component mounter body via the suction nozzle. As a result, there is a problem in that there is an increased possibility of electrostatic damage to the component.

[0040] With the above in mind, the structure of the resin suction nozzle 20 in this embodiment will be described. Figure 2 is a cross-sectional view of the suction nozzle 20 in this embodiment. As shown in the figure, the suction nozzle 20 has a tip 110 and a terminal 120. Note that the reflector, which will be described later, is omitted from this figure.

[0041] Terminal 120 is located at the rear end of suction nozzle 20 and is intended to set the potential at the location where terminal 120 is attached to 0V. In other words, the other end of terminal 120, which is not attached to suction nozzle 20, is connected to ground and has a potential of 0V. Note that terminal 120 does not necessarily have to be located at the rear end of suction nozzle 20. The same function can be achieved as long as it is located anywhere on suction nozzle 20.

[0042] The negative pressure generating source 17 is a device for applying negative pressure to the inside of the suction hole. By applying negative pressure to the inside of the suction hole, the component P is sucked onto the tip 110 of the suction nozzle 20 through the suction hole.

[0043] The tip portion 110 is the tip portion of the suction nozzle 20 and has a suction hole for suctioning the component P. The suction nozzle 20 including the tip portion 110 is a cylindrical component made of conductive resin that is a composite of carbon and resin.

[0044] It is preferable to use fibrous carbon nanotubes as the carbon to be composited with the resin, as this allows for easy and uniform dispersion within the resin and a larger surface area than conventional carbon, making the carbon less likely to peel off from the resin and improving the durability of the suction nozzle.

[0045] The amount of carbon nanotubes mixed into the resin to impart conductivity to the suction nozzle 20 is preferably 3 to 6% by weight of carbon nanotubes to the resin. Furthermore, the resin to be composited with carbon is preferably a super engineering plastic or an engineering plastic. Furthermore, the resin is more preferably a polyamide resin, a polycarbonate resin, a polyacetal resin, a polybutylene terephthalate resin, a modified polyphenylene ether resin, a polyphenylene sulfide resin, a polyarylate resin, a liquid crystal polymer resin, a polysulfone resin, a polyether sulfone resin, a polyether ketone resin, a polyetherimide resin, a polyamide imide resin, a polyimide resin, a polyether ether ketone resin, a polybenzimidazole resin, or a polycarbonate resin.

[0046] As will be explained later, it is preferable that the volume resistance value of the suction nozzle 20 is 1 to 1000 MΩcm. It has been found that by compounding the above resin with carbon nanotubes in the above ratio, the suction nozzle 20 becomes a conductive resin with a volume resistance value of 1 to 1000 MΩcm.

[0047] FIG. 3 is a table showing the correlation between the volume resistance value of the suction nozzle 20 and the discharge completion time calculated assuming the shape of an actual suction nozzle.

[0048] For the calculation, the component mounting suction nozzle of the present invention was modeled on CAD, and when 10 kV of static electricity was applied to the tip 110 of the suction nozzle 20, the time until discharge was completed to the terminal 120 attached to the suction nozzle 20 at a position 10 mm away from the tip 110 was calculated by simulation.

[0049] According to this, if the volume resistance of the suction nozzle 20 is 1 to 1000 MΩcm, the charge on the component P will be discharged completely in 6 to 8 msec. Generally, it is said that damage to components due to static electricity often occurs due to a sudden discharge of 0.00015 msec or less, so it is thought that electrostatic damage will hardly occur if the discharge time is this long.

[0050] Based on the above, by molding a suction nozzle from a material in which super engineering plastic or engineering plastic is combined with carbon nanotubes at a weight ratio of 3 to 6% to the resin, it is possible to create a suction nozzle that prevents scratches on parts, is highly durable, has low maintenance costs, and is less likely to cause damage to parts due to discharge.

[0051] (1.3 Configuration of component position detection device) The configuration of the component position detecting device according to this embodiment will be described.

[0052] FIG. 4 is a cross-sectional view of the component position detection device of this embodiment. Note that some of the components described in FIG. 2 will not be described again. The component position detection device is a device for accurately recognizing the pickup position of the component P at the tip of the suction nozzle 20. By using this device, it is possible to detect in advance that the component is not being picked up at the expected position at the tip of the suction nozzle 20. This makes it possible to avoid failure in mounting the component on the board in advance.

[0053] Component position detection device 400 in this embodiment includes, as components, reflector 230 (an example of a reflecting section), first lighting 210 (an example of a first light-projecting section), first camera 220 (an example of a first light-receiving section), second lighting 211 (an example of a second light-projecting section), and second camera 221 (an example of a second light-receiving section).

[0054] The first illuminator 210 emits a light beam from the front end toward the rear end of the suction nozzle 20. This light beam may be, for example, coherent infrared light (an example of light of the first frequency), but is not limited to this and may be any light beam that can be reflected by the reflector 230. The light beam emitted by the first illuminator 210 is irradiated toward the reflector 230 from a direction that will not be blocked by the component P that has been picked up at the expected position of the suction nozzle 20. The reflector 230 reflects the light irradiated from the first illuminator 210 toward the front end of the suction nozzle 20 from the rear end. Note that the first illuminator 210 may be composed of multiple light sources.

[0055] The first camera 220 receives and captures the light emitted from the first illuminator 210 and reflected by the reflector 230. That is, the first camera 220 is installed on the optical path of the light reflected by the reflector 230. The first camera 220 is, for example, a CMOS image sensor, but any device capable of measuring and estimating the shape of the image of the reflected light may be used. For example, a photodiode array or a photoconductive cell may be used. The first camera 220 receives and captures the reflected light at a position where the light reflected by the reflector 230 is partially blocked by the component P picked up at the expected position of the suction nozzle 20. That is, the first camera 220 is installed on the opposite side of the suction nozzle 20 across the component P. The first camera 220 may also be equipped with a filter that has a higher transmittance for light of the frequency of the first illuminator than for light of the frequency of the second illuminator, so as to eliminate interference from the light of the second illuminator 211 and more predominantly receive the light of the first illuminator 210. This filter may be a physical filter placed in front of the optical sensor, or may be software or hardware that processes the electrical signal generated as a result of receiving light by the optical sensor using digital signal processing, etc. Note that it is desirable that the light emitted from the first illuminator 210 be coherent light so that light other than the reflected light (especially the diffused light from the first illuminator 210) does not get into the first camera 220.

[0056] The second illuminator 211 emits light rays from the front end toward the rear end of the suction nozzle 20. This light ray preferably has a different frequency from the light ray emitted by the first illuminator 210. For example, the light ray may be red coherent light (an example of light of the second frequency), but is not limited to this and may be any light ray that is reflected by the component P. The light ray emitted by the second illuminator 211 is irradiated toward the reflector 230 from a direction that is partially blocked by the component P that has been picked up at the expected position of the suction nozzle 20. The light ray emitted by the second illuminator 211 and irradiated onto the component P is reflected by the component P, and the reflected light becomes light that travels in a direction from the rear end toward the front end of the suction nozzle. The second illuminator 211 may be composed of multiple light sources.

[0057] The second camera 221 is installed on the opposite side of the suction nozzle 20 across the component P. The second camera 221 receives and captures the light emitted from the second illuminator 211 and reflected by the component P. That is, the second camera 221 is installed on the optical path of the light reflected by the component P. The second camera 221 is, for example, a CMOS image sensor, but any device capable of measuring and estimating the shape of the image of the reflected light may be used. For example, a photodiode array or a photoconductive cell may be used. The second camera 221 may also be equipped with a filter that has a higher transmittance for light of the second illuminator frequency than light of the first illuminator frequency, so as to eliminate interference from the light of the first illuminator 210 and more predominantly receive the light of the second illuminator 211. This filter may be a physical filter installed in front of the optical sensor, or software or hardware that processes the electrical signal generated as a result of light reception by the optical sensor using digital signal processing or the like. It is desirable that the light emitted from the second illuminator 211 be coherent light so that light other than the reflected light (particularly the diffused light from the second illuminator 211) does not get around to the second camera 221.

[0058] The reflector 230 reflects the light emitted by the first illuminator 210. The direction of travel of the reflected light is preferably approximately parallel to the central axis of the suction nozzle 20 (the vertical direction in FIG. 4 ). This is because distortion is less likely to occur in the image captured by the first camera 220. However, the reflected light does not necessarily have to be approximately parallel to the central axis of the suction nozzle 20. For example, the reflected light may be directed at an angle so that it hits the entire surface of the component P picked up at the desired position. The reflector 230 also absorbs the light emitted by the second illuminator 211. If the light emitted by the second illuminator 211 were reflected, the image captured by the second camera 221 would be blurred due to the reflected light from the reflector 230. Note that the reflector 230 does not necessarily have to "absorb" the light emitted by the second illuminator 211. As is clear from the above-mentioned purpose, it is sufficient that the reflectance of the reflector 230 for the light of the second illumination 211 is low enough that the light reflected from the component P and the light reflected from the reflector 230 can be clearly distinguished.

[0059] FIG. 5 shows an example of the structure of the reflector 230 that achieves the above-described function. The reflector 230 has an inclined portion 501 on the side irradiated with light from the first illuminator 210 and the second illuminator 211. The cross section of the inclined portion is shaped like a sawtooth, and the angle of the inclined portion 501 is set so that the light emitted from the first illuminator 210 is approximately parallel to the central axis of the suction nozzle 20. Preferably, the inclined portion 501 is arranged in a shape that is rotationally symmetrical by 180 degrees around the central axis of the suction nozzle 20. This is because, when the first illuminator 210 is composed of multiple light sources, irradiating the light from these light sources at the same incident angle onto the reflector makes it easier to generate reflected light with a wider illumination range. However, it is not necessary to provide an inclined portion on the entire surface of the reflector. For example, in the figure, an inclined portion is also provided on the side irradiated with light from the second illuminator 211, but this is not essential.

[0060] As described above, it is preferable that the side of the reflector 230 that is irradiated with light from the first illuminator 210 and the second illuminator 211 has the property of reflecting the frequency of light emitted by the first illuminator and absorbing the light emitted by the second illuminator. To this end, a material that reflects the light of the first illuminator 210 and absorbs the light of the second illuminator is painted on the surface of the reflector 230 or is contained in the material of the reflector 230.

[0061] In this embodiment, the light of the first illumination 210 is infrared light, and the light of the second illumination 211 is red light. A possible material that reflects infrared light (wavelengths of 780 nm or more) and absorbs red light (wavelengths of 625-780 nm) is a near-infrared reflective pigment (an example of a light-reflective pigment) in which particulate iron oxide is mixed into a pigment. Here, the light-reflective pigment is a pigment that exhibits high reflectance to light. In particular, a pigment that exhibits high reflectance to light with wavelengths longer than near-infrared light and lower reflectance to visible light is called a near-infrared reflective pigment. The above function can be realized by utilizing the ability to adjust the reflection characteristics of a specific wavelength band by changing the size of the iron oxide particles mixed into the pigment. Figure 7 shows an example of the relationship between wavelength and reflectance shown by a material in which Co and Fe2O3 have been mixed into a white pigment (Kanagawa Prefectural Industrial Technology Center Research Report No. 19 / 2013 [https: / / www.kistec.jp / wp / wp-content / uploads / filebase / reports_of_research / H25 / 12Originals03.pdf]). It shows that a large difference in reflectance has been achieved between the infrared light region and the visible light region, which are sandwiched between wavelengths of 780 nm.

[0062] Although Fig. 7 shows an example of a material using iron oxide, any material having similar properties may be used. For example, titanium oxide may be used, or an Fe-Cr-O or copper-magnesium compound may be used. Specific examples of such materials can be found in, for example, patent literature (JP Patent Publication No. 2007-204296).

[0063] Another structural example of the reflector 230 is shown in FIG. 8. In this embodiment, as shown in FIG. 8(a), a dielectric multilayer film is formed on the incident surface side of the inclined portion 501. FIG. 8(b) shows an enlarged view of the main part. The inclined portion 501 is formed by repeatedly and periodically stacking materials with high refractive indexes (e.g., titanium oxide, tantalum pentoxide, aluminum oxide, zirconia, or hafnium oxide) and materials with low refractive indexes (e.g., silicon dioxide or magnesium fluoride). The thickness of each film is an integer multiple of a quarter wavelength of the incident light. This ensures that the reflected light from each layer interface is in phase with the light reflected from the surface of the reflector 230, thereby achieving a very high reflectance for the incident light. In this embodiment, the multilayer film is made of a dielectric material; however, the material does not necessarily have to be a dielectric material as long as it performs the same function. Furthermore, although the multilayer film is described as being formed by repeatedly and periodically stacking materials with different refractive indexes, the multilayer film may be formed by alternately stacking films made of different materials, and the number of layers may be two or more. Furthermore, the film materials do not necessarily have to be of two types. As long as the same function is exhibited, there may be layers of three or more types of materials, and the order in which the materials are stacked does not need to be strictly periodic.

[0064] Figure 9 shows the results of a simulation of the reflection characteristics when the multilayer dielectric film created this time is formed on the reflector 230. It can be seen that a characteristic in which the reflectance differs greatly between the infrared light region and the visible light region, which sandwich a wavelength of 780 nm between them, has been achieved.

[0065] 5 and 8 described above may be used simultaneously. In this embodiment, the light emitted by the first illuminator 210 is infrared light, the light emitted by the second illuminator 211 is red light, and the material coated on the reflector reflects infrared light and absorbs red light. However, the respective lights do not necessarily have to be infrared light and red light. As is clear from the spirit of the present invention, it is sufficient that the first illuminator 210 and the second illuminator 211 are configured to have different frequencies, and that the material coated on the reflector 230 has a high reflectivity for the first frequency and a low reflectivity for the second frequency. To achieve the objective of clearly capturing the reflected light of the first frequency with the first camera 220 and clearly suppressing the reflected light of the second frequency reaching the second camera 221, it is desirable that the material coated on the reflector 230 has a reflectivity for the first frequency that is four or more times higher than the reflectivity for the second frequency.

[0066] The reflecting plate 230 may be formed integrally with the suction nozzle 20. If the reflecting plate 230 and the suction nozzle 20 are molded integrally from the same resin material, the entire assembly can be manufactured inexpensively.

[0067] It is desirable to color at least a part of the suction nozzle 20 black to prevent diffuse reflection of the light emitted by the first illuminator 210 and the second illuminator 211 and their reflected light. For example, the tip side of the suction nozzle 20 is colored black. Furthermore, since black is sufficient to prevent diffuse reflection, the resin that is the material of the suction nozzle 20 may itself be black.

[0068] In addition, although the suction nozzle 20 and the reflector 230 are made of resin in this embodiment, they do not necessarily have to be made of resin. They may be made of metal or ceramic as long as there are no problems with durability or conductivity.

[0069] (1.4 Reflector manufacturing method) An example of a manufacturing method in which the reflector 230 and the suction nozzle 20 are integrally formed from resin will be described with reference to FIG.

[0070] 6-1 in Fig. 6 shows an example of the configuration of a mold for molding the reflector 230. The mold consists of a pair of upper and lower molds. The shape of the reflector 230 is carved into the lower mold, and the upper mold covers it. The shape carved into the lower mold is donut-shaped, and a through-hole that is larger than the inner diameter of the suction nozzle 20 and smaller than the outer diameter of the suction nozzle 20 is formed in the center of the molded reflector 230.

[0071] Resin that will be the material for the reflector 230 is supplied to this mold to first mold the reflector 230. At this time, it is desirable to mix a light-reflecting pigment into the resin, as described above.

[0072] Furthermore, the light-reflecting pigment may be unevenly distributed on the reflecting surface (the lower surface in the figure) of the reflector 230. Unmelted light-reflecting pigment particles exist in the molten mixed resin material injected into the mold. These particles lose fluidity and accumulate in a sawtooth shape on the reflecting surface, making it possible to unevenly distribute a large amount of light-reflecting pigment on the reflecting surface.

[0073] If no light-reflecting pigment is mixed in, the light-reflecting pigment may be applied to the surface of the reflector 230 after it has been molded.

[0074] Furthermore, when a multilayer dielectric film is formed on the reflector 230, each thin film may be laminated by vapor deposition after the reflector 230 is formed.

[0075] 6-2 in Fig. 6 shows an example of the configuration of a mold for molding the suction nozzle 20. The mold consists of a pair of upper and lower dies. The lower die has a pillar inserted into the center of the space created by the upper and lower dies, thereby molding the cylindrical suction nozzle 20. The lower die has a recess into which the reflector 230 molded by the mold in Fig. 6-1 can be inserted.

[0076] When molding the suction nozzle 20, the reflector 230 molded using the mold shown in 6-1 in FIG. 6 is inserted into the lower mold in advance (6-3 in FIG. 6). From this state, the space created by the upper and lower molds is filled with resin that will be the material for the suction nozzle 20. The resin filled at this time does not necessarily have to be the same material as the reflector 230. For example, it may be a resin that does not contain a light-reflecting pigment.

[0077] As mentioned above, the reflector 230 has a through-hole in the center that is larger than the inner diameter of the suction nozzle 20 and smaller than the outer diameter of the suction nozzle 20, so it sinks into the molded suction nozzle 20. This makes it possible to manufacture a resin part in which the reflector and suction nozzle are integrally formed.

[0078] (2. Operation) The operation of component position detecting device 400 having the above-described configuration will now be described.

[0079] (2.1 Picking up parts) First, component P is sucked onto the tip of suction nozzle 20. With negative pressure generated inside suction nozzle 20 by negative pressure generator 17, suction nozzle 20 is brought close to component P. Then, component P is sucked onto the tip of suction nozzle 20. Component position detection device 400 is a mechanism for checking whether component P has been sucked into the desired position of suction nozzle 20. (2.2 Position detection from the rear of the component) Infrared light is emitted from the first light source 210. The emitted infrared light is reflected by the reflector 230. The reflector 230 is provided with the aforementioned inclined portion 501 and reflects infrared light with high reflectivity, resulting in strong reflected light from the reflector 230 toward the component P. A portion of the reflected light is blocked by the component P before reaching the first camera 220. By capturing the unblocked light with the first camera 220, an image is obtained in which the component P appears as a dark image and the surrounding background appears as a bright image, as shown in FIG. 10(a). From the shape of this dark image created by the blockage by the component P, the position of the component P picked up at the tip of the suction nozzle 20 can be estimated by image analysis or other techniques. Because the light reflected from the reflector 230 is strong, the contrast between the bright image and the dark image is high, enabling highly accurate image analysis.

[0080] (2.3 Position detection from the front of the component) Red light is emitted from the second illumination 211. Part of the emitted red light is reflected by the component P. By capturing the light reflected from the component P with the second camera 221, an image is obtained in which the component P appears as a bright image and the surrounding background appears as a dark image, as shown in FIG. 10(b). Some of the light that does not hit the component P may reach the reflector 230, but because the reflector 230 has a low reflectivity for red light, this light does not mix with the image captured by the second camera 221. From the shape of this bright image formed by the light reflected from the component P, the position of the component P picked up by the tip of the suction nozzle 20 can be estimated by image analysis or other techniques. Because the light reflected from the reflector 230 does not mix with the image, the contrast between the bright image and the dark image is high, enabling highly accurate image analysis. [Industrial Applicability]

[0081] The present disclosure is applicable to an apparatus or system that, when a suction nozzle of a component mounting apparatus picks up a component, checks whether the component has been picked up at a desired position. [Explanation of symbols]

[0082] 1. Component mounting equipment 1a Base 2. Substrate transport mechanism 3. Circuit Board 4 Head movement mechanism 5 Mounting head 6 nozzle unit 6a Mechanism 7 Nozzle shaft 8 Nozzle holder 9 carts 10 Tape Feeder 11 Carrier tape 12 parts reels 13 Main unit cover 17 Negative pressure source 20 suction nozzle 110 Tip 120 terminals 210 First Lighting 211 Second Lighting 220 First Camera 221 Second Camera 230 Reflector 400 Parts position detection device P parts

Claims

1. A device for detecting the position of a component picked up by a suction nozzle of a component mounter, a first light-emitting unit that emits light of a first frequency from a front end side toward a rear end side of the suction nozzle; a reflecting section that reflects the light emitted by the first light-emitting section from the rear end side toward the front end side of the suction nozzle; a first light receiving unit that receives light of the first frequency reflected by the reflecting unit, the reflecting portion has a multilayer film in which materials having different refractive indices are stacked. Part position detection device.

2. The multilayer film is formed by periodically laminating films made of materials having different refractive indices. The component position detecting device according to claim 1 .

3. the first light projecting unit emits coherent light, the reflecting portion has an inclined portion, The first light receiving unit is the light emitting unit is disposed on the optical path of light emitted from the first light emitting unit and reflected by the inclined portion, and on the opposite side of the component from the suction nozzle. The component position detecting device according to claim 1 .

4. a second light-emitting unit that is disposed on the opposite side of the suction nozzle with the component interposed therebetween and that emits light of a second frequency from the front end side toward the rear end side of the suction nozzle; a second light receiving unit that receives light that is emitted by the second light emitting unit and reflected by the component, the first frequency and the second frequency are different values; The component position detecting device according to claim 1 .

5. The thickness of each film of the multilayer film is an integer multiple of one-fourth the wavelength of light of the first frequency. The component position detecting device according to claim 1 .

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