WO2015001633A1

WO2015001633A1 - Imaging device and production equipment

Info

Publication number: WO2015001633A1
Application number: PCT/JP2013/068271
Authority: WO
Inventors: 神藤　高広
Original assignee: 富士機械製造株式会社
Priority date: 2013-07-03
Filing date: 2013-07-03
Publication date: 2015-01-08
Also published as: JP6267200B2; JPWO2015001633A1

Abstract

The purpose of this invention is to provide the following: an imaging device that makes it possible, with the overall size of said imaging device reduced, to also reduce loads associated with imaging and image processing, for example, even when imaging a plurality of subjects; and production equipment provided with said imaging device. This imaging device is provided with a varifocal lens, an imaging control unit that applies distance-dependent voltages to said varifocal lens, a storage unit that stores a preset effective region for each of a plurality of subjects, and an image processing unit that generates combined data by combining, on the basis of the aforementioned effective regions, a plurality of pieces of image data acquired by imaging the plurality of subjects.

Description

Imaging device and production equipment

The present invention relates to an imaging apparatus that images a target object, and a production facility that controls production processing based on image data obtained by the imaging apparatus.

An imaging apparatus is used in various fields. For example, Patent Document 1 discloses a configuration in which a component camera or a board camera is applied to a component mounter that is a production facility used for production of various products in the industrial field. Has been. In this component mounter, the accuracy of the mounting control is improved by reflecting the state of the electronic component or the like recognized based on the image data captured by the imaging device in the mounting control. Here, an imaging device applied to a production facility such as a component mounter may be restricted in external dimensions and installation location due to a request for downsizing of the component mounter, for example.

For this reason, a fixed focus lens or a variable focus lens (see Patent Document 2) may be employed in the optical system of the image pickup apparatus in order to reduce the external dimensions. In such a configuration, when there are a plurality of objects to be imaged, the distances from the image sensor to the object to be imaged are approximately equal to each other or within the field of view of the imaging device fixed to the component mounter. In order to accommodate the object, an optical path from the object to the image sensor is formed using an optical member such as a reflector.

JP 2013-26278 A JP 2011-86847 A

By the way, along with a request for improving the accuracy of production processing for production facilities, the types of image data required in the control of production processing are also diversified. Therefore, when a fixed focus lens is adopted in the optical system, if the imaging objects are separated from each other by a predetermined distance or more, the adjustment of the optical path length is not easy even if an optical member is used, There is a possibility that suitable image data cannot be obtained. Further, when a variable focus lens is employed in the optical system, there is a concern about an increase in loads such as imaging processing and image processing because imaging is performed for each imaging target.

The present invention has been made in view of such circumstances, and is capable of reducing the load of imaging processing and image processing even in imaging of a plurality of objects while reducing the size of the entire apparatus. It is an object of the present invention to provide a production facility including an apparatus and an imaging device.

The imaging apparatus according to the present invention includes a variable focus lens that can change a focal length in accordance with an applied voltage, and a plurality of objects at different distances from the imaging apparatus when the imaging apparatus images each of the distances. An imaging control unit that applies a corresponding voltage to the variable focus lens, and a part of the imaging region that can be imaged by the imaging device including the target object as an effective region in advance for each of the plurality of target objects. A storage unit that stores each of the set effective areas; an image processing unit that generates a combined data by combining a plurality of pieces of image data acquired by imaging the plurality of objects based on the effective areas; Is provided.

According to such a configuration, since the imaging apparatus employs a variable focus lens in the optical system, it is possible to perform imaging while focusing on a plurality of objects at different distances. Therefore, the apparatus can be reduced in size as compared with the mechanical type that varies the distance between the plurality of lenses. In addition, when imaging a plurality of objects, the image processing unit combines the image data based on the effective areas each including the plurality of objects, so that imaging processing and image processing outside the effective area are not necessary. The load of these processes can be reduced. Therefore, when the production facility includes an imaging device having such a configuration, the production facility control device can acquire a plurality of necessary image data as combined data, so that efficient production process control is performed. Can do.

1 is an overall view showing a component mounter in an embodiment. It is the front view which expanded a part of component mounting head. It is an A direction arrow directional view of FIG. It is a block diagram which shows the control apparatus and imaging device of a component mounting machine. It is a top view which shows the structure of the liquid crystal lens of a board | substrate camera. It is a figure which shows the lens characteristic of a liquid crystal lens. It is a figure which shows the combined data which combined several image data. It is a flowchart which shows the mounting process by a component mounting machine. FIG. 9 is an activity diagram showing a mounting process in FIG. 8.

<Embodiment>
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments in which an imaging device and a production facility of the present invention are embodied will be described with reference to the drawings. In the present embodiment, the production facility targets a circuit board product produced by mounting electronic components on a circuit board, and constitutes a production line for this circuit board product. Moreover, in this embodiment, the structure whose production equipment is a component mounting machine is illustrated. The component mounter is a device that mounts a plurality of electronic components on a circuit board, for example, in an integrated circuit manufacturing process. This circuit board is coated with cream solder at an electronic component mounting position by, for example, a screen printing machine, and is sequentially transported through a plurality of component mounting machines to mount the electronic component. Thereafter, the circuit board on which the electronic component is mounted is transported to a reflow furnace and soldered to constitute an integrated circuit as a circuit board product.

(Overall configuration of component mounter)
The overall configuration of the component mounter 1 will be described with reference to FIGS. The component mounter 1 includes a board transfer device 10, a component supply device 20, a component transfer device 30, a component camera 60, a head camera device 70, and a control device 90. The

devices

10, 20, 30 and the component camera 60 are provided on the base 2 of the component mounter 1 and are controlled by the control device 90. Further, as shown in FIG. 1, the horizontal direction of the component mounter 1 (direction from the upper left to the lower right in FIG. 1) is the X-axis direction, and the horizontal longitudinal direction of the component mounter 1 (from the upper right to the lower left in FIG. 1). The direction of heading is the Y-axis direction, and the vertical height direction (vertical direction in FIG. 1) is the Z-axis direction.

The board transfer device 10 transfers the circuit board B in the X-axis direction and positions the circuit board B at a predetermined position. This board | substrate conveyance apparatus 10 is a double conveyor type comprised by the 1st conveyance mechanism 11 and the 2nd conveyance mechanism 12 which were arranged in parallel by the Y-axis direction. The first transport mechanism 11 includes a pair of

guide rails

11a and 11b and a conveyor belt (not shown). The pair of

guide rails

11a and 11b are arranged in the upper part of the base 2 in parallel with the X-axis direction, and guide the circuit board B which is placed on the conveyor belt and conveyed. The circuit board B transported to a predetermined position is clamped by being pushed up from the base 2 side by a clamping device (not shown). Since the second transport mechanism 12 is configured in the same manner as the first transport mechanism 11, detailed description thereof is omitted.

The component supply device 20 is a device that supplies electronic components mounted on the circuit board B. The component supply device 20 is disposed on the front side in the Y-axis direction of the component mounter 1 (the left front side in FIG. 1). In the present embodiment, the component supply apparatus 20 is a feeder system that uses a plurality of cassette-type feeders 21. The feeder 21 includes a feeder main body portion 21a that is detachably attached to the base 2, and a reel housing portion 21b that is provided on the rear end side of the feeder main body portion 21a. The feeder 21 holds a supply reel 22 around which a component packaging tape is wound by a reel accommodating portion 21b.

The above-described component packaging tape includes a carrier tape in which electronic components are stored at a predetermined pitch, and a top tape that is bonded to the upper surface of the carrier tape and covers the electronic components. The feeder 21 pitch feeds the component packaging tape drawn from the supply reel 22 by a pitch feed mechanism (not shown). The feeder 21 peels the top tape from the carrier tape to expose the electronic component. Thereby, the feeder 21 supplies the electronic component so that the component transfer device 30 can suck the electronic component at the component supply position Ps located on the front end side of the feeder main body 21a.

The component transfer device 30 is a device that transfers electronic components from the component supply position Ps to the mounting position of the circuit board B. In the present embodiment, the component transfer device 30 is an orthogonal coordinate type disposed above the substrate transfer device 10 and the component supply device 20. In the component transfer device 30, a Y-axis moving table 32 is provided on a pair of Y-axis rails 31 extending in the Y-axis direction so as to be movable in the Y-axis direction. The Y-axis moving table 32 is controlled by the operation of the Y-axis motor 33 via a ball screw mechanism. The Y-axis moving table 32 is provided with an X-axis moving table 34 that can move in the X-axis direction. The X-axis moving table 34 is controlled by the operation of the X-axis motor 35 via a ball screw mechanism (not shown).

Also, a component mounting head 40 (corresponding to the “moving head” of the present invention) is attached to the X-axis moving table 34 of the component transfer apparatus 30. The component mounting head 40 supports a plurality of suction nozzles 42 so as to be movable up and down by a nozzle holder 41 (corresponding to a “holder member” of the present invention) that can rotate around an R axis parallel to the Z axis. In the component mounting head 40, the frame 43 is fixed to the X-axis moving table 34, and the R-axis motor 44 and the Z-axis motor 45 are supported on the upper part of the frame.

More specifically, the nozzle holder 41 of the component mounting head 40 is formed in a cylindrical shape as a whole, and is connected to the output shaft of the R-axis motor 44 via an index shaft 46 as shown in FIG. . As a result, the nozzle holder 41 is configured to be rotationally controlled by the R-axis motor 44 and the index shaft 46. In addition, as shown in FIG. 3, the nozzle holder 41 can slide a plurality of (12 in this embodiment) nozzle spindles 47 in the Z-axis direction at equal intervals in the circumferential direction on the circumference concentric with the R-axis. I support it. As shown in FIG. 2, suction nozzles 42 are attached to the lower ends of the nozzle spindles 47 in a replaceable manner. Thus, the nozzle holder 41 supports each suction nozzle 42 via each nozzle spindle 47.

Also, a nozzle gear 47 a is formed at the upper end of the nozzle spindle 47. The nozzle gear 47a meshes with the θ-axis gear 51 supported on the outer peripheral side of the index shaft 46 so as to be relatively rotatable so as to be slidable in the Z-axis direction. The θ-axis gear 51 has a tooth width of a predetermined length in the Z-axis direction, is connected to a θ-axis motor (not shown) via a speed change mechanism 52, and is rotationally driven by the θ-axis motor. With such a configuration, when the θ-axis motor rotates, all the nozzle spindles 47 supported by the nozzle holder 41 rotate via the speed change mechanism 52 and the θ-axis gear 51. Accordingly, each suction nozzle 42 rotates with respect to the nozzle holder 41 by the rotation of the θ-axis motor, and is configured to be able to be controlled for rotation by the θ-axis motor or the like.

Further, a compression spring 48 is provided on the outer peripheral side of the nozzle spindle 47 and between the upper surface of the nozzle holder 41 and the lower surface of the nozzle gear 47a. The nozzle spindle 47 is biased upward with respect to the nozzle holder 41 by the compression spring 48, and the upward movement is restricted by the large diameter portion 47 b formed at the lower end contacting the lower surface of the nozzle holder 41. ing. That is, the state in which the large-diameter portion 47b of the nozzle spindle 47 is in contact with the nozzle holder 41 is the state in which the suction nozzle 42 attached to the nozzle spindle 47 is raised most.

The nozzle lever 53 is in contact with the upper end surface of the nozzle spindle 47 that is indexed to a lifting position H1 described later among the plurality of nozzle spindles 47. The nozzle lever 53 is connected to the output shaft of the Z-axis motor 45 via a ball screw mechanism (not shown), and is controlled to move in the Z-axis direction by the rotational drive of the Z-axis motor 45. With this configuration, when the Z-axis motor 45 rotates, the nozzle lever 53 presses the nozzle spindle 47, and the nozzle spindle 47 moves the nozzle spindle 47 downward in the Z-axis direction against the elastic force of the compression spring 48.

As described above, the suction nozzle 42 is moved up and down with the movement of the nozzle spindle 47 in the Z-axis direction by the lifting mechanism constituted by the Z-axis motor 45, the compression spring 48, and the like. Also, with this configuration, the component mounting head 40 can sequentially index the plurality of suction nozzles 42 to the lift position H1 of the component mounting head 40 by the rotation of the nozzle holder 41, and the circuit board B from the component supply position Ps. Is provided so as to be movable to the positioned component mounting position. A negative pressure is supplied to each suction nozzle 42 from a suction nozzle driving device (not shown) via a nozzle spindle 47. Thus, each suction nozzle 42 can suck the electronic component T at its tip.

The component camera 60 is a digital imaging device having an imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The component camera 60 captures an image within a range that falls within the camera field of view based on a control signal from the control device 90 that is communicably connected, and sends image data acquired by the image capture to the control device 90. The component camera 60 is fixed to the base 2 so that the optical axis is in the Z-axis direction, and is configured to be able to image the electronic component T in a state of being sucked by the suction nozzle 42. The control device 90 that has acquired the image data from the component camera 60 recognizes the holding state of the electronic component T by the suction nozzle 42 by image processing. Thus, by correcting the position and angle of the suction nozzle 42 in accordance with the holding state of the electronic component T, it is possible to improve the accuracy of the mounting control.

The head camera device 70 is an imaging device that is disposed on the outer peripheral side of the suction nozzle 42 and is fixed to the component mounting head 40 via a bracket (not shown). In this embodiment, the head camera device 70 is used for both imaging of the tip of the suction nozzle 42 and imaging of the upper surface of the circuit board B. In addition, as shown in FIG. 3, the tip of the suction nozzle 42 is indexed to the lift position H1 in the nozzle holder 41, and the two standby positions H1- adjacent to the lift position H1 are indexed. The tip of the suction nozzle 42 indexed to 1, H1 + 1 is set as an object to be imaged. The image data obtained by the imaging is used for image processing in which the control device 90 recognizes the holding state of the electronic component T by the suction nozzle 42 and the mounting state of the circuit board B.

The head camera device 70 includes an imaging case 71, a plurality of irradiation bodies 72, an optical member 73, and a camera body 80, as shown in FIG. The imaging case 71 is disposed so as to surround a part of the plurality of suction nozzles 42 disposed on the circumference from the outer peripheral side. The plurality of irradiators 72 are light sources such as light emitting diodes disposed on the cylindrical inner peripheral surface of the imaging case 71 on the suction nozzle 42 side toward the reflector disposed at the rotation center of the nozzle holder 41.

The optical member 73 is disposed inside the imaging case 71 and forms an optical path from the tip of the suction nozzle 42 that is an imaging target to the camera body 80. Specifically, the optical member 73 receives the two first prisms 73a arranged at positions corresponding to the standby positions H1-1 and H1 + 1 of the suction nozzle 42 and the light refracted by the respective first prisms 73a. The second prism 73b that refracts light parallel to the optical axis of the camera body 80.

Further, the second prism 73 b of the optical member 73 refracts light incident from the opening formed on the lower surface of the imaging case 71 into light parallel to the optical axis of the camera body 80. With such an optical member 73, the camera body 80 uses the tip portion of the suction nozzle 42 indexed to the standby positions H1-1 and H1 + 1 and the member positioned below the component mounting head 40 as the imaging object. It is possible. Further, the first prism 73a and the second prism 73b are formed so that the lengths of the optical paths from the suction nozzles 42 indexed to the standby positions H1-1 and H1 + 1 to the camera body 80 are equal. .

As shown in FIG. 4, the camera body 80 includes a fixed lens 81, a liquid crystal lens 82 (corresponding to the “variable focus lens” of the present invention), an imaging element 83, an imaging control unit 84, and a storage unit 85. And an image processing unit 86. The fixed lens 81 and the liquid crystal lens 82 are arranged so as to be coaxial with the optical axis of the image sensor 83. The fixed lens 81 is an objective lens arranged at the outermost part of the lens unit constituting the optical system, and has a function of preventing entry of foreign matters into the unit.

The liquid crystal lens 82 is a variable focus lens capable of changing the focal length according to the applied voltage. In this embodiment, a liquid crystal lens in which a liquid crystal layer is disposed between two electrodes is employed as the variable focus lens. Specifically, as shown in FIG. 5, the liquid crystal lens 82 includes a first electrode 82a having a rectangular outer shape and a second electrode 82b having a circular shape. The first electrode 82a and the second electrode 82b each have two electrodes provided on a pair of transparent substrates arranged in parallel, and the same liquid crystal layer is interposed between the two electrodes.

When the liquid crystal lens 82 having such a configuration is applied with different voltages to the first electrode 82a and the second electrode 82b, the alignment state of the liquid crystal molecules changes according to the direction of the electric field, and acts as a lens. Further, by making the applied voltage Vb to the second electrode 82b higher than the applied voltage Va to the first electrode 82a (Va <Vb), the liquid crystal lens 82 substantially functions as a convex lens. When the amplitudes of the applied voltages Va and Vb are constant, the focal length of the liquid crystal lens 82 can be controlled by the difference between the applied voltages Va and Vb.

The image sensor 83 is a CCD or CMOS, and converts the light transmitted through the fixed lens 81 and the liquid crystal lens 82 into an electrical signal. The imaging control unit 84 controls the operation of the liquid crystal lens 82 constituting the lens unit based on a control signal input from the outside, a set value stored in the storage unit 85, and the like. Further, the imaging control unit 84 images the object by converting the electrical signal converted by the imaging element 83 into a digital signal. Then, the imaging control unit 84 transfers an image acquired by imaging to the control device 90.

The storage unit 85 is configured by a flash memory or the like, and stores various setting values used for imaging processing, lens characteristics of the liquid crystal lens 82, and the like. The set value includes each effective area set in advance for each of a plurality of objects, with a part of the imaging area (camera field of view) that can be captured by the camera body 80 including an object as an effective area. It is. Here, the camera body 80 is capable of imaging when the component mounting head 40 moves above the tip portions of the two suction nozzles 42 indexed to the standby positions H1-1 and H1 + 1 and above the circuit board B. The three objects combined with the upper surface portion of the circuit board B are set as objects of imaging. That is, the effective area corresponds to three areas obtained by dividing the camera field of view corresponding to the three objects.

As described above, the three objects are stored in the camera field of the camera body 80 by the optical member 73. However, the imaging control unit 84 has a difference in the length of the optical path from the tip of the suction nozzle 42 to the upper surface of the circuit board B to the camera body 80, which is larger than the depth of field of the lens unit. I cannot focus at the same time. That is, when either one is focused, the other is not focused. Therefore, by performing imaging processing based on a predetermined effective area, image processing for an out-of-focus part of the camera field of view is omitted, thereby speeding up imaging processing and reducing processing load. Yes.

Here, the lens characteristics stored in advance in the storage unit 85 indicate the relationship between the voltage applied to the liquid crystal lens 82 and the distance from the object to the camera body 80 (hereinafter also referred to as “object distance”). Is. In the present embodiment, as lens characteristics corresponding to the liquid crystal lens 82, as shown in FIG. 6, as a map showing the object distance determined by the applied voltage Va to the first electrode 82a and the applied voltage Vb to the second electrode 82b. Yes. In addition, this object distance has a correlation with the focal distance that varies depending on the voltage applied to the liquid crystal lens 82. Therefore, the lens characteristics may indirectly indicate the relationship between the applied voltage and the focal length.

Furthermore, the various setting values stored in the storage unit 85 are targets indicating each distance from the head camera device 70 to the plurality of objects (corresponding to the length of the optical path from the image sensor 83 to the plurality of objects). Object distance information and focal distance information indicating each focal distance of the liquid crystal lens 82 corresponding to each distance of a plurality of objects are included. In the present embodiment, on the assumption that the imaging control unit 84 recognizes in advance the approximate object distance from the imaging element 83 to the imaging object, a predetermined voltage corresponding to the object distance is applied to the liquid crystal lens. A method is adopted in which focusing is performed by applying the voltage to 82. In other words, the imaging control unit 84 corresponds to the object distance acquired from the object distance information and the effective area acquired from the focal distance information when performing imaging processing of a predetermined effective area in the camera field of view. The applied voltage to the liquid crystal lens 82 is calculated based on the focal length and the lens characteristics. According to such an imaging process, the adjustment process of the voltage applied to the liquid crystal lens 82 based on the image process is not required, so that the efficiency of the imaging process can be improved.

The image processing unit 86 combines a plurality of image data acquired by imaging a plurality of objects based on each effective area to generate combined data. Here, in the present embodiment, the camera body 80 of the head camera device 70 has the three objects as imaging targets as described above. Among these, the tip of the suction nozzle 42 indexed to the standby positions H1-1 and H1 + 1 of the nozzle holder 41 is formed with an equal optical path length to the camera body 80 by the optical member 73. Therefore, since the imaging control unit 84 can focus on the tip of each suction nozzle 42 at the same time, it is possible to capture images simultaneously.

The image data combining process by the image processing unit 86 is first performed by image data obtained by imaging the tip of each suction nozzle 42 and imaging of the upper surface of the circuit board B at different times as shown in the upper part of FIG. Image data is acquired. At this time, each imaging with a different target object is performed based on each effective area (inside the thick line frame in FIG. 7) preset for each of the plurality of target objects. Therefore, image processing is not performed on the outside of the effective area (shaded area in FIG. 7), and a part of the image data is missing. Next, the image processing unit 86 combines based on the corresponding effective areas so as to interpolate the respective image data, and focuses on the three objects as shown in the lower part of FIG. Generate sharp combined data.

The control device 90 is mainly composed of a CPU, various memories, and a control circuit, and controls the operation of the component mounting head 40 based on image data (including combined data) acquired by imaging of the component camera 60 and the head camera device 70. To do. As shown in FIG. 4, in the control device 90, an input / output interface 94 is connected to a mounting control unit 91, an image processing unit 92, and a storage unit 93 via a bus. A motor control circuit 95 and an imaging control circuit 96 are connected to the input / output interface 94.

The mounting control unit 91 controls the position of the component mounting head 40 and the operation of the suction mechanism via the motor control circuit 95. More specifically, the mounting control unit 91 inputs information output from various sensors provided in the component mounting machine 1 and results of various recognition processes. The mounting control unit 91 then sends a control signal to the motor control circuit 95 based on the control program stored in the storage unit 93, information from various sensors, and the results of image processing and recognition processing. The image processing unit 92 acquires image data obtained by imaging the component camera 60 and the head camera device 70 via the imaging control circuit 96, and executes image processing according to the application. This image processing includes, for example, processing such as binarization of image data, filtering, and hue extraction.

The storage unit 93 is configured by an optical drive device such as a hard disk device or a flash memory. The storage unit 93 includes a control program for operating the component mounter 1, image data and combined data transferred from the component camera 60 and the head camera device 70 to the control device 90 via the bus and communication cable, and image processing. Temporary data for processing by the unit 92 is stored. The input / output interface 94 is interposed between the CPU and storage unit 93 and the

control circuits

95 and 96, and adjusts data format conversion and signal strength.

The motor control circuit 95 controls the Y-axis motor 33, the X-axis motor 35, the R-axis motor 44, the Z-axis motor 45, and the θ-axis motor based on the control signal from the mounting control unit 91. Thus, the component mounting head 40 is positioned in each axial direction, and the suction nozzle 42 is controlled to have a predetermined angle. The imaging control circuit 96 controls imaging by the component camera 60 and the head camera device 70 based on imaging control signals from the CPU of the control device 90 and the like. Further, the imaging control circuit 96 acquires image data obtained by imaging of the component camera 60 and the head camera device 70 and stores the acquired image data in the storage unit 93 via the input / output interface 94.

(Mounting process in component mounter)
The mounting process of the electronic component T by the component mounter 1 will be described with reference to FIGS. This mounting process corresponds to a “production process” of a target product by a production facility (component mounting machine). The component mounter 1 shifts to mounting control of the electronic component T after executing the preparation process. In this mounting control, first, a suction process (step 11 (hereinafter, “step” is referred to as “S”)) in which the electronic components T are sequentially suctioned by the plurality of suction nozzles 42 is executed. Next, the component mounting head 40 is moved to above the mounting position on the circuit board B (S12). At this time, the component mounting head 40 passes above the component camera 60, and at that time, the imaging process of the electronic component T by the component camera 60 is executed. Thereafter, a mounting process (S13) for sequentially mounting the electronic components T on the circuit board B is executed.

Then, it is determined whether or not all the electronic components T have been mounted (S14), and the above processing (S11 to S14) is repeated until the mounting is completed. In the mounting process (S13), in parallel with the raising and lowering and indexing of the suction nozzle 42, imaging of the tip of the suction nozzle 42 indexed to the standby positions H1-1 and H1 + 1 and the upper surface of the circuit board B are performed. Processing is executed. Further, the mounting control unit 91 controls the mounting of the electronic component T based on the holding state of the electronic component T by each suction nozzle 42 and the mounting state of the circuit board B in order to improve mounting accuracy. Therefore, the control device 90 recognizes the holding state of the electronic component T and the mounting state of the circuit board B by performing image processing on the image data and the combined data acquired by the imaging of the component camera 60 and the head camera device 70. I have to.

More specifically, as shown in FIG. 9, the control device 90 first rotates the nozzle holder 41 to index the specific suction nozzle 42 that sucks the component to the lift position H1 (S131). As a result, the suction nozzles 42 used for the next mounting and the suction nozzles 42 used for the previous mounting are indexed at the standby positions H1-1 and H1 + 1 of the nozzle holder 41. At this time, the imaging control unit 84 of the head camera device 70 inputs a control signal from the control device 90, and performs imaging using the upper surface portion of the circuit board B as an imaging target (S231).

Specifically, the imaging control unit 84 first acquires the object distance from the upper surface of the circuit board B to the camera body 80 based on the object distance information stored in the storage unit 85. Next, the imaging control unit 84 acquires the focal length of the liquid crystal lens 82 corresponding to the object distance of the upper surface portion of the circuit board B based on the focal length information stored in the storage unit 85.

Then, the imaging control unit 84 applies a voltage calculated based on the focal length and the lens characteristics to the liquid crystal lens 82 so that the camera body 80 is focused on the upper surface of the circuit board B. Then, the imaging control unit 84 acquires an effective area from the storage unit 85 when the upper surface portion of the circuit board B is an imaging target. The imaging control unit 84 acquires partial image data that falls within the acquired effective area in the camera field of view by imaging, and temporarily stores it in the storage unit 85.

Subsequently, the control device 90 positions the component mounting head 40 and raises and lowers the suction nozzle 42 based on the control program, the correction value calculated after the previous mounting, the holding state of the recognized electronic component T, and the like. Then, the electronic component T is mounted at a predetermined position (S132). At this time, the imaging control unit 84 of the head camera device 70 inputs a control signal from the control device 90, and the tip of the suction nozzle 42 that is indexed to the standby positions H1-1 and H1 + 1 in the component mounting head 40 is displayed. Imaging is performed as an imaging target (S232).

Specifically, the imaging control unit 84 acquires the object distance from the tip of each suction nozzle 42 to the camera body 80 based on the object distance information. Here, the length of the optical path from the image sensor 83 to the tip of each suction nozzle 42 is set equal by the optical member 73. Therefore, in the object distance information, the same value is written as the object distance related to the tip of each suction nozzle 42. And the imaging control part 84 acquires the focal distance of the liquid-crystal lens 82 corresponding to the target object distance of the front-end | tip part of each suction nozzle 42 based on focal distance information.

Next, the imaging control unit 84 applies a voltage calculated based on the focal length and the lens characteristics to the liquid crystal lens 82, and the camera body 80 is focused on the tip of each suction nozzle 42. To do. Then, the imaging control unit 84 acquires an effective area from the storage unit 85 when the tip of the suction nozzle 42 is an imaging target. The imaging control unit 84 acquires partial image data that falls within the acquired effective area in the camera field of view by imaging, and temporarily stores it in the storage unit 85.

As described above, when the head camera device 70 images a plurality of objects with different object distances, the imaging control unit 84 applies a voltage corresponding to each object distance to the liquid crystal lens 82 to perform focusing. Do. Further, in the imaging process (S231) using the upper surface portion of the circuit board B as an object, the mounting state of the circuit board B by the previous mounting and the printing state of the cream solder at the next mounting position are included in the image data. In the imaging process (S232) using the tip portions of the plurality of suction nozzles 42 as an object, the holding state of the electronic component T by the suction nozzles 42 used in the next mounting and the suction nozzles 42 used in the previous mounting are used. Whether or not the electronic component T is taken home is included in the image data.

The image processing unit 86 of the head camera device 70 combines the image data stored in the storage unit 85 by the respective imaging processes (S231, S232) based on the corresponding effective areas (S233). As a result, as shown in FIG. 7, combined data in which a plurality of objects at different object distances are in focus is generated. This combined data is transferred from the head camera device 70 to the control device 90 and stored in the storage unit 93 of the control device 90.

The mounting control unit 91 of the control device 90 determines whether or not the mounting process is completed depending on whether or not all the held electronic components T are mounted on the circuit board B (S133). If the mounting process is not completed (S133: No), the control device 90 executes a correction process such as calculating a correction value of the control program based on the analysis result of the combined data by the image processing unit 92. (S134). Further, based on the above analysis result, the control device 90 holds the electronic component T by the suction nozzle 42 used for the next mounting, or brings back the electronic component T by the suction nozzle 42 used for the previous mounting. Recognition processing such as the presence or absence of the circuit board B and the mounting state of the circuit board B is performed (S135).

Then, the control device 90 executes indexing of the suction nozzle 42 (S131) and the like again. In addition, when an event such as a mounting failure or a loss of the suction nozzle 42 is recognized by the state confirmation process (S135), the control device 90 performs a recovery process corresponding to each event. The control device 90 repeats such an operation, and when the mounting of all the electronic components T required in the mounting process is completed (S133: Yes), the mounting process ends.

(Effects of the configuration of the embodiment)
According to the component mounting machine 1 described above, the imaging device (head camera device 70) is configured to employ the variable focus lens (liquid crystal lens 82) in the lens unit constituting the optical system. As a result, the head camera device 70 can also be used for imaging a plurality of objects at different object distances. Further, since the focal length of the liquid crystal lens 82 can be changed by the applied voltage, the apparatus can be reduced in size as compared with a mechanical type that changes the distance between a plurality of lenses.

Further, the image processing unit 86 is configured to generate combined data obtained by combining image data obtained by imaging a plurality of objects based on each effective area. Thereby, the imaging control unit 84 and the image processing unit 86 do not need imaging processing and image processing outside the effective area, and can reduce the load of these processing. Therefore, since the control device 90 of the component mounter 1 can acquire a plurality of necessary image data as combined data, the correction process (S134) and the state recognition process (S135) can be performed efficiently.

The imaging control unit 84 performs focusing of the lens unit by applying a voltage calculated based on the object distance information, focal length information, and lens characteristics to the liquid crystal lens 82 when imaging the object. It was. As described above, the head camera device 70 employs a focusing method in which a predetermined voltage is applied to the liquid crystal lens 82 on the assumption that the object distance is recognized in advance. Therefore, since the head camera device 70 does not require adjustment of the applied voltage based on image processing at the time of imaging, the imaging process can be speeded up and the imaging process can be performed efficiently.

The head camera device 70 forms the optical path by the optical member 73 so that the lengths of the optical paths from the imaging element 83 to the two different suction nozzles 42 are equal. As a result, the two suction nozzles 42 are in different regions in the camera field of the camera body 80, and images can be simultaneously captured with the same focal length. Therefore, since the head camera device 70 can image a plurality of effective areas at the same time on the assumption that the object distance is generally recognized, the imaging process can be made more efficient.

In this embodiment, the production facility is a component mounter 1 that forms a production line for circuit board products and mounts electronic components on the circuit board. Such a component mounter 1 is desired to have a finer target product and higher production process accuracy, and the application of the head camera device 70 having the above-described configuration to the component mounter 1 is particularly useful. . In the present embodiment, the head camera device 70 includes the tip of the suction nozzle 42 and the upper surface of the circuit board B in the imaging target. Then, the control device 90 recognizes the holding state of the suction nozzle 42 and the mounting state of the circuit board B based on the combined data generated by combining the image data obtained by capturing the plurality of objects (S135). Thereby, since the mounting control part 91 of the control apparatus 90 can perform mounting control based on each state, while being able to improve the precision of mounting control, generation | occurrence | production of mounting defect can be suppressed.

In addition, the component mounting head 40 of the component transfer apparatus 30 is configured to support the plurality of suction nozzles 42 by the nozzle holder 41. In the head camera device 70, when the predetermined suction nozzle 42 is indexed at the lift position H1, the two suction nozzles 42 indexed at two standby positions H1-1 and H1 + 1 adjacent to the lift position H1. Each of the tip portions is included in the object to be imaged. That is, the tip portion of the suction nozzle 42 before and after the mounting process is an object to be imaged. Thereby, the control apparatus 90 can recognize the holding state of the electronic component T by the suction nozzle 42, the presence / absence of take-out, the presence / absence of a tip portion, and the like. Therefore, it is possible to further improve the accuracy of the mounting control and promptly shift to the execution of an appropriate recovery process.

<Modification of Embodiment>
In the present embodiment, the head camera device 70 uses the tip portions of the two suction nozzles 42 indexed at the standby positions H1-1 and H1 + 1 and the upper surface portion of the circuit board B as objects to be imaged. The number of objects to be imaged may be three or more as long as there are a plurality of objects, and various members can be objects to be imaged as long as they are within the camera field of view by the configuration of the optical member 73 and the like. For example, when the component mounting head 40 moves above the component supply device 20 during the suction process (S11), the electronic component T at the component supply position Ps may be used as an imaging target. Thereby, the control apparatus 90 can recognize the supply state of the electronic component T by image processing, and can reflect in the adsorption | suction process.

Further, the imaging control unit 84 applies a predetermined voltage calculated for each of the objects to the liquid crystal lens 82 in order to improve the efficiency of the imaging process when imaging each object (S231). , S232). On the other hand, when a certain amount of time may be required for the imaging process, the lens unit is focused on the object to be imaged, for example, by adjusting the applied voltage based on at least a part of the image processing. You may do it. Thereby, even when the variable focus lens is affected by the imaging environment including the ambient temperature, it is possible to reliably focus on the object to be imaged. In addition to the liquid crystal lens exemplified in this embodiment, a liquid lens may be employed as the variable focus lens.

In the present embodiment, the configuration applied to the head camera device 70 is exemplified as the imaging device having the above configuration. On the other hand, the present invention can be similarly applied to other imaging devices such as the component camera 60 used in the component mounter 1. That is, a variable focus lens is used for the lens unit of the component camera 60, and in addition to the electronic component T held by the suction nozzle 42, the component camera 60 picks up a part of the substrate transfer device 10, the component supply device 20, and the like. It is good also as a structure made into a target object.

Further, the imaging control unit 84 may be configured to correct the applied voltage when the calculated predetermined voltage is applied to the liquid crystal lens 82. That is, when the imaging target includes the electronic component T held at the tip of the suction nozzle 42, the imaging control unit 84 acquires the dimension information of the electronic component T included in the control program. Then, the imaging control unit 84 corrects the applied voltage based on the length in the optical axis direction of the head camera device 70 in the electronic component T.

Specifically, the imaging control unit 84 first acquires, for example, a part number as dimension information of the electronic part T included in the control program. Then, the imaging control unit 84 acquires the dimension of the camera body 80 in the optical axis direction from the component table in which the dimension of the electronic component T is recorded corresponding to the component number. The dimension in the direction of the optical axis corresponds to the traveling direction of light at a portion that intersects the electronic component T in the optical path refracted by the optical member 73. Subsequently, the imaging control unit 84 calculates the amount of change in the voltage applied to the liquid crystal lens 82 as the adjustment voltage when the focal length of the lens unit is shortened by the dimension based on the lens characteristics.

Then, the imaging control unit 84 corrects the applied voltage calculated based on the focal length information and the lens characteristics by adding the adjustment voltage. When this corrected voltage is applied to the liquid crystal lens 82, the focus of the lens unit of the camera body 80 is in a state where it is aligned with the side surface of the electronic component sucked by the suction nozzle 42. Thereby, the applied voltage can be adjusted with higher accuracy, so that sharper image data can be acquired. Further, in such a correction method, when the electronic component T is included in the object to be imaged, as described above, when the electronic component at the component supply position Ps is imaged, the present configuration is applied to the component camera 60. The present invention can also be applied to the configuration applied to the above.

In this embodiment, the imaging control unit 84, the storage unit 85, and the image processing unit 86 constitute the camera body 80 of the head camera device 70. On the other hand, the imaging control unit 84, the storage unit 85, and the image processing unit 86 may be arranged in a control device 90 that is communicably connected to the head camera device 70. In such a configuration, a part of the control device 90 constitutes a part of the imaging device, and the same effects as those of the present embodiment are achieved. However, from the viewpoints of reducing the processing load on the control device 90 and reducing the communication processing between the head camera device 70 and the control device 90, the embodiment exemplified in this embodiment is preferable.

Furthermore, in addition to being applied to the component mounting machine 1, the imaging device is configured to generate a combination data based on each effective area by imaging a plurality of objects having different object distances. Alternatively, it may be used as a single imaging device. For example, the imaging device can also be applied to other printing machines and inspection machines that constitute a production line for circuit board products. Furthermore, the imaging device can also be applied to production equipment such as machine tools and general-purpose assembly machines that produce products other than circuit board products. Even in such a configuration, the same effects as in the embodiment can be obtained, and the application to a production facility where miniaturization and high accuracy of a product are desired is particularly useful.

1: component mounting machine (production equipment), 2: base 10: substrate transfer device, 20: component supply device, 30: component transfer device 40: component mounting head (moving head)
41: Nozzle holder (holder member), 42: Suction nozzle 60: Component camera 70: Head camera device (imaging device)
71: Imaging case 72: Irradiating body 73: Optical member 73a: First prism 73b: Second prism 80: Camera body
81: Fixed lens, 82: Liquid crystal lens (variable focus lens)
83: Imaging device, 84: Imaging control unit, 85: Storage unit, 86: Image processing unit, 90: Control device, Ps: Component supply position, B: Circuit board, T: Electronic component

Claims

A variable focus lens capable of changing the focal length according to the applied voltage;
An imaging control unit that applies a voltage corresponding to each distance to the variable focus lens when the imaging device images a plurality of objects at different distances from the imaging device;
A storage unit that stores each of the effective areas set in advance for each of the plurality of objects, using a part of the imaging area that can be captured by the imaging apparatus as an effective area.
An image processing unit configured to combine a plurality of pieces of image data acquired by imaging the plurality of objects based on the effective areas to generate combined data;
An imaging apparatus comprising:
The storage unit
Object distance information indicating each of the distances from the imaging device to the plurality of objects;
Focal length information indicating each focal length of the variable focus lens corresponding to each of the distances of the plurality of objects;
Storing lens characteristics indicating a relationship between a voltage applied to the variable focus lens and a focal length;
The imaging according to claim 1, wherein the imaging control unit applies a voltage calculated based on the object distance information, the focal length information, and the lens characteristics to the variable focus lens when imaging the object. apparatus.
The imaging device takes three or more objects as imaging targets, and a plurality of optical paths from the plurality of objects to the imaging device among the three or more objects are equal to each other. An optical member that forms the optical path of at least one of the objects;
The imaging control unit performs imaging by applying a voltage corresponding to the distance to a variable focus lens, assuming that the plurality of objects having the same optical path length are at the same distance from the imaging device. Item 3. The imaging device according to Item 1 or 2.
The imaging apparatus according to any one of claims 1 to 3,
A control device that is communicably connected to the imaging device, acquires image data obtained by imaging from the imaging device, and controls a production process based on the combined data and a pre-stored control program;
Production equipment with.
The production equipment according to claim 4, wherein the production equipment is for circuit board products produced by mounting electronic components on a circuit board, and constitutes a production line for the circuit board products.
The production equipment is
One or more suction nozzles for sucking and holding the electronic component supplied to the component supply position;
A movable head that supports the suction nozzle so as to be movable up and down and is movable from the component supply position to a component mounting position where the circuit board is positioned;
A component mounter for mounting the electronic component on the circuit board under the control of the control device,
The plurality of objects include a tip portion of the suction nozzle and an upper surface portion of the circuit board,
The production facility according to claim 5, wherein the control device controls mounting of the electronic component based on a holding state of the suction nozzle and a mounting state of the circuit board included in the combined data obtained by imaging of the imaging device.
The moving head supports a plurality of the suction nozzles by a rotatable holder member, and sequentially indexes the plurality of suction nozzles to a lifting position where the suction head can be lifted and lowered by the rotation of the holder member. Configured and possible
At the tip of the suction nozzles included in the plurality of objects, two predetermined indexing nozzles are indexed at the elevation position, and two indexed positions at the two standby positions adjacent to the elevation position are obtained. The production facility according to claim 6, wherein each tip of the suction nozzle is included.
When the electronic parts are included in the plurality of objects, the imaging control unit acquires dimensional information of the electronic parts included in the control program, and the length in the optical axis direction of the imaging device in the electronic parts The production facility according to any one of claims 5 to 7, wherein the applied voltage to the variable focus lens is further corrected based on the following.