JP5248122B2 - Automatic coating system and method for controlling automatic coating system - Google Patents

Description

  The present invention relates to an automatic coating system using a contact coating unit that contacts a coating object and applies a coating liquid to the coating object, and a coating liquid supply unit that supplies the coating liquid to the contact coating unit, and an automatic coating system. The present invention relates to a method for controlling a coating system.

  Conventionally, an automatic painting system such as a painting robot is known. In the case of a painting robot, the spray gun is operated with a robot hand and moved along the object in a pre-programmed route so that the desired painting result can be obtained, while the paint is applied using pressurized air obtained from a compressor, etc. A structure for spraying from a nozzle of a spray gun is used.

  In conventional automatic painting systems such as painting robots, there are many spray or airbrush type painting heads as described above. However, depending on the form and specifications of painting and the characteristics of the paint or object to be used, spray or airbrush type painting is not always necessary. The head is not always suitable.

For example, in the case of hand-painting, there is a so-called contact coating method in which an impregnated body such as a brush, a brush, or a tip of a felt pen is used as an applied body of paint. Such a method of contact painting is required when expressing patterns such as straight lines, curves, or characters,
Moreover, it is suitable also when a coating material needs to be apply | coated in the form that a coating area | region and a non-coating area | region are clearly divided. In addition, such contact painting methods can be expressed in various ways by selecting the shape, hardness, size (thickness), etc. of the tip of the coated body, and can be applied without masking. There are advantages such as being possible.

In the above contact coating method, not only is the manual coating operation performed while the paint is applied to the application body such as a brush or brush, but the paint is contained and applied by pressure (or by gravity). It is also conceivable to use an application tool (for example, Patent Document 1 below) that is supplied to the application body.
Japanese Patent Laid-Open No. 11-332643

  There are few known automatic coating systems that automatically perform a painting operation by a contact coating method using the impregnated body as described above as a coating body.

  For example, it is conceivable to apply a paint by moving an applicator (dispenser) as described in Patent Document 1 described above with a general-purpose robot hand, but when the paint area is large, the paint capacity of the applicator is large. Depending on the case, it may be necessary to change the application tool many times or to replenish the coating material, resulting in problems such as increased work interruptions and increased costs. Further, in the application tool configured to supply the coating material to the application body by gravity, there is a problem in that the supply of the coating material may be insufficient depending on the posture of the tool, resulting in fading.

  In order to be able to handle a large coating area and to perform stable coating, a coating head (or dispenser) operated with a robot hand should be coated with a coating material such as a brush, brush, or felt tip. It is considered that a configuration in which the paint is mounted and the paint is supplied from an external paint tank is suitable.

  However, conventionally, there are almost no automatic coating systems that perform contact coating using such an application body, and the paint is stably supplied to the application body of the coating head without the paint leaking or dripping. There has been little known about sophisticated structures that are capable of high-precision and high-quality painting.

  In particular, it is considered that an automatic coating system using this type of contact coating technique requires that a pattern such as a line, a character, or a figure be formed by contact coating without masking. Depending on the application, it may be required to form a coating pattern with extremely high accuracy and high quality.

  For example, it may be required to perform contact coating with a very small error with a line width (equal width or variable width) of several mm for several mm and several cm for several cm. In addition, with respect to the coating concentration, there is a possibility that it is required to form a coating pattern with a uniform coating concentration without causing color unevenness.

  Conventionally, there has been almost no automatic coating (automatic coating) system capable of controlling contact coating with high accuracy and obtaining a high-quality finish.

  In the above description, the paint is considered as the coating liquid applied to the object to be coated. However, the above problem is common when the coating liquid to be applied is another liquid such as a chemical liquid. For example, as a technique for attaching a liquid substance to an object, not limited to a paint, there is a need for a technique for attaching various chemical solutions such as for treatment and surface treatment to the object. Depending on the liquid substance used or the characteristics of the object, a technique such as a spray or airbrush method is not always suitable, and the above-described contact painting technique is more preferable. It is thought that there is not much.

  In view of the above circumstances, an object of the present invention is to provide an automatic coating system that can perform high-precision and high-quality contact coating and a method for controlling the automatic coating system.

In order to solve the above problems, in the present invention, in an automatic application system and a method for controlling an automatic application system,
Operating a coating apparatus having a contact application means for applying a coating solution to the application object in contact with the application object, with a robot arm, and moving the contact application means in contact with the application object, Let the coating device perform contact coating,
Photographing the coating pattern of the coating liquid formed on the coated object by the coating device by photographing means mounted on the robot arm together with the coating device;
Analyzing the image data captured by the imaging means, performing image processing for generating information relating to the application pattern formation state of the application liquid, and applying the application operation of the application apparatus based on the information relating to the application pattern formation state of the application liquid, Or, feedback control of the operation of the robot arm ,
In the image processing, information on the actual values of the line width and the density of the coating pattern of the coating liquid is generated from the image data captured by the imaging unit, and the information on the actual values of the line width and the density is a predetermined line. Feedback control of the line width and concentration of the coating pattern of the coating solution so as to approach the target values of width and concentration,
The application pattern of the coating liquid immediately after formation on the object to be coated according to the coating direction of the coating device using a driving unit that moves the photographing optical axis of the photographing unit to a different relative position with respect to the coating device. A configuration is adopted in which the photographing means is moved to a follow-up position for photographing .

With such a configuration, the application pattern of the coating liquid formed on the object to be coated is photographed by the photographing unit, and the coating pattern formation state of the coating liquid is performed through image processing of the image data photographed by the photographing unit. Information, that is, information on the line width and density is acquired as information on the contact application state, the application operation of the application device or the operation of the robot arm is controlled, and the desired contact application operation is executed.

  Further, according to the coating direction of the coating apparatus, the imaging unit is moved to a tracking position for imaging the coating pattern of the coating liquid immediately after being formed on the coating object, thereby moving the imaging unit on the coating object. The formation state of the coating pattern of the coating liquid immediately after the formation of can be fed back to the contact coating operation.

  According to the above configuration, according to the present invention, the imaging state of the coating pattern of the coating liquid immediately after formation on the object is photographed by the photographing means, and information on the coating pattern forming state of the coating liquid is fed back to the contact coating operation. Accordingly, a high-precision and high-quality contact coating operation can be performed in accordance with the intended coating conditions.

  Hereinafter, as an example of the best mode for carrying out the invention, an embodiment relating to an automatic coating system for performing coating by operating a coating head for performing contact coating with a robot arm will be described. That is, in the following, an example relating to an automatic coating system that performs coating on an object to be coated (application object) by contact coating will be described as an example of a coating liquid that is applied to the object to be coated (application object).

  FIG. 1 shows an outline of an automatic painting system employing the present invention.

  In FIG. 1, reference numeral 100 denotes a servo gun for applying and coating a paint. The servo gun 100 is operated by a robot arm 200.

  Although details of the servo gun 100 will be described later, a dispenser chip 180 is attached to the tip of the servo gun 100 as a paint application body. The dispenser chip 180 has an application body chip formed of a felt-like impregnated body (soft porous body) through which the paint can permeate, and the paint is supplied to the dispenser chip 180 through a path not shown in FIG. The

  By operating the servo gun 100 with the robot arm 200 and moving the dispenser chip 180 in contact with the object to be coated (the object to be coated), an application pattern is formed on the object to be coated.

  The operation of the robot arm 200 is controlled by the control unit 900. Depending on the shape of the coating pattern, lines, characters, images, and the like can be represented on the object to be coated with paint. As described above, the application pattern on the object to be applied can be an arbitrary expression such as a line, a character, or an image. However, for the sake of convenience, the formation operation of the paint application pattern (application trajectory) is also referred to as “drawing”.

  This drawing process is performed by the control unit 900 controlling the operation of the servo gun 100 in synchronization with the control of the robot arm 200. Drawing performed in this way, that is, formation of a coating pattern, is performed by the control unit 900 controlling the operations of the robot arm 200 and the servo gun 100 in accordance with the drawing program 901. The robot arm 200 and the servo gun 100 are controlled by the control unit 900 via the interface 902.

  Furthermore, in this embodiment, the actual application pattern formation state is detected, and information on the detected application pattern formation state is fed back to the operation of the robot arm 200 and the servo gun 100, so that the application pattern can be obtained under the desired conditions. Is provided with a control mechanism for enabling formation of

  In this embodiment, for this purpose, a CCD camera 800 is provided as an imaging unit, and the CCD camera 800 is controlled so as to track (follow) the coating pattern formed by the servo gun 100. In the example described later, the CCD camera 800 is mounted on the robot arm 200 together with the servo gun 100, and is controlled so as to follow (follow) the coating pattern formed by the servo gun 100 via a drive mechanism described later.

  An image captured by the CCD camera 800 is subjected to image analysis by an image processing unit 903. The image processing unit 903 can be configured using dedicated hardware, or can be configured by software of the control unit 900. The image processing unit 903 extracts information on the formation state of the application pattern by the servo gun 100 from the image taken by the CCD camera 800, particularly information such as the line width and density of the applied paint in the example described later.

  The image analysis by the image processing unit 903 is based on identifying a coating pattern and other areas, that is, a coating area and a non-coating area from an image captured by the CCD camera 800. This can be performed using a known image recognition process. If the application area can be identified from the non-application area, the line width (w) drawn by the servo gun 100 based on the imaging magnification, the drawing direction of the servo gun 100, and the like that are known in advance from the configuration of the CCD camera 800 and the imaging conditions. Information about can be detected. In addition, if the application region can be identified from the non-application region, information regarding the density (d) inside the application region can be detected.

  Then, the control unit 900 controls the operation of the robot arm 200 and the servo gun 100 based on the information regarding the line width and density drawn by the servo gun 100 output from the image processing unit 903, thereby performing the expected operation based on the drawing program 901. A high-quality coating pattern can be formed with high accuracy according to the above conditions, for example, the desired line width or density.

  Here, an example of the drawing program 901 executed by the control unit 900 will be described with reference to FIG. This example is merely an example, and is a pseudo-specialization specialized to briefly explain the present embodiment, and it is not necessary to actually configure the drawing program in this way. For example, the drawing command and the coordinate system can have many equivalent configurations other than those shown in FIG.

  The drawing program shown in FIG. 9 includes drawing commands CMD1, CMD2, CMD3... CMDn, CMDn + 1. Here, the drawing command CMDn is expressed by a vector from the start point Pn (Xn, Yn, Zn) to the end point Pn + 1 (Xn + 1, Yn + 1, Zn + 1).

  The vector expression included in the drawing command CMDn is theoretically only the coordinate values of the start point Pn and the end point Pn + 1, but in order to reduce the calculation load during the drawing process described later, the vector expression is changed from the start point Pn to the end point Pn + 1. May be stored (for example, expressed by angle information in two planes such as xy and xz).

  Alternatively, as described later, in the present embodiment, when the drawing direction needs to be evaluated with respect to the drawing command CMDn, whether or not a direction change has occurred in the drawing direction between the immediately preceding drawing command CMDn-1 and the drawing command CMDn. Since (only) becomes a problem, the direction of the previous drawing command CMDn-1 and the drawing command CMDn is compared in advance when creating the drawing program, and flag information indicating whether or not the direction change has occurred, that is, the direction change. A flag may be generated and stored in the drawing command CMDn. With such a configuration, it is possible to further reduce the calculation load during the drawing process.

  The curve can be approximately expressed as a set of drawing commands corresponding to a vector having a very short length, but other drawing command formats for expressing the curve may be prepared.

  In the present embodiment, one drawing command CMDn includes at least information regarding the target values of the line width wi and the density di as parameters for controlling drawing (coating pattern formation), or further target values such as writing pressure. Information related to this shall be included. Here, the pen pressure target value is expressed by, for example, the distance between the servo gun 100 that holds the dispenser chip 180 and the object to be coated.

  Therefore, the drawing program is configured by arranging each of a large number of the drawing commands CMD1, CMD2, CMD3... CMDn, CMDn + 1... On a storage device such as a memory or an HDD in a specific storage format.

  Here, FIG. 2 shows a configuration example of the automatic painting system of FIG. 1, and FIG. 3 shows a more specific example of the basic configuration of the servo gun 100 in FIG.

  FIG. 2 shows an overall configuration of an automatic painting system employing the present invention, and FIG. 3 shows a detailed configuration of a servo gun 100 as a painting head operated by a robot arm 200 in the automatic painting system of FIG. In the following, the basic configuration of the servo gun 100 will be described first with reference to FIG. 3, and then the automatic coating system of FIG. 2 using the servo gun 100 will be described.

  FIG. 3 shows a cross-sectional structure of the main part of the servo gun 100.

  The servo gun 100 of FIG. 3 has a housing 101, and a chamber 103 that controls the supply of paint and the pressure of coating is fixed to the front end of the housing 101 via shafts 126 and 126. The housing 101 and the chamber 103 are configured by cutting out from a metal material or die casting, for example.

  A pressure chamber 103a having a predetermined diameter (about φ10) is formed in the rear portion of the chamber 103. The pressure chamber 103a functions as a cylinder chamber having a cylindrical cross-sectional shape in which a piston 102 described later can slide coaxially.

  In front of the pressure chamber 103a (right side in the figure), there is a paint path 103b for supplying paint from a filling side valve unit 142, which will be described later, and to the side, discharge paint to a discharge side valve unit 141, which will be described later. The paint path 103c for this purpose is perforated.

  A packing set 120 is fixed to the rear end portion of the pressure chamber 103 a by a packing presser 104, and a tip of a piston 102 driven by a servo motor 114 described later is inserted into the packing set 120 and sealed with the packing set 120. In this state, the piston 102 slides to adjust the pressure inside the pressure chamber 103a.

  The pressure of the paint in the pressure chamber 103a is detected by the pressure sensor head 191. The pressure sensor head 191 is attached to the chamber 103 so that the probe (not shown) is exposed to the pressure inside the pressure chamber 103a. The pressure detection method of the pressure sensor head 191 is arbitrary such as a thin gauge type, a semiconductor strain gauge type, and a piezoelectric type.

  In the front part of the chamber 103, a paint path 103d through which the paint discharged from the discharge side valve unit 141 on the side of the chamber passes is perforated. The paint path 103d communicates with the nozzle port 103e at the tip of the chamber 103.

  In addition, O-rings 123, 123... Are arranged at joints such as the paint paths 141c and 103d and the paint paths 142c and 103b as necessary.

  A dispenser chip 180 is attached to the nozzle port 103e as a coating means. The dispenser chip 180 has a substantially tube-like structure, has a coupling portion coupled to the nozzle port 103e by screwing or the like at the rear end portion, and supplies the coating material from the nozzle port 103e to the coating body 181 at the tip.

  The applicator 181 constitutes the main part of the coating means for applying the paint. For example, the nib used in stationery such as brushes, felt pens, markers, etc., with various hair lengths, hardnesses, densities and the like adjusted according to the application. An applied body chip formed from a felt-like impregnated body (soft porous body) that can be penetrated by a paint as used in the above can be used. The application body 181 may have any structure as long as the pressure can be adjusted as described later and the applied paint can be transmitted to the tip of the coating material 181 that contacts the object to be coated. . Needless to say, the supply pressure of the paint adjusted as described later should be controlled by the penetration (transmission) characteristics of the paint of the application body 181.

  Next, the structure of the filling side valve unit 142 and the discharging side valve unit 141 that fills the pressure chamber 103a and supplies (discharges) the pressure chamber 103a to the dispenser chip 180 will be described.

  Here, the structure common to the valve units 142 and 141 will be described at the same time. In this embodiment, the valve units 142 and 141 are formed as a common part having a substantially common structure, and when used as any one of the filling side or the discharging side, unnecessary openings are sealed with a blind cover or the like. The specifications are as follows. With such a configuration, the cost can be reduced.

  Each of the filling side valve unit 142 and the discharge side valve unit 141 has needle valves 109 and 109 inside, and opening and closing of the needle valves 109 and 109 is performed by air cylinder units 152 and 151 arranged behind each valve unit. By controlling, the passage of the paint is controlled to be turned on / off.

  Needle valves 109 and 109 each have a head having a diameter larger than that of the rear shaft portion, and a slope is cut at the rear end of these heads. The slopes of the rear ends of the heads of the needle valves 109 and 109 are opposed to the slopes of the openings 142b and 141b in the filling side valve unit 142 and the discharge side valve unit 141, and the needle valves 109 and 109 and the openings 142b, The passage of the paint can be controlled depending on whether 141b is separated or closely adhered.

  The fronts of the openings 142b and 141b of the valve units 142 and 141 are formed by punching from the front into inner diameters of the needle valves 109 and 109 that can accommodate the heads. The front portions of the openings 142b and 141b are sealed by blind covers 108 and 108 through O-rings 122 and 122, respectively. The rear portions of the openings 142b and 141b have narrower inner diameters and penetrate to the large diameter portions where the packing sets 121 and 121 at the rear ends of the valve units 142 and 141 are mounted. The large-diameter portion of the opening in which the packing sets 121 and 121 are mounted is perforated from the rear (left side in the drawing) of the valve units 142 and 141.

  The packing sets 121 and 121 are fixed by packing pressers 107 and 107. In the packing sets 121 and 121, shafts 110 and 110 having tips connected to needle valves 109 and 109 respectively penetrate. With such a configuration, the needle valves 109 and 109 can be operated via the shafts 110 and 110 by the air cylinder units 152 and 151 described later in a state of being sealed by the packing sets 121 and 121.

  Next, the paint path in the filling side valve unit 142 and the discharge side valve unit 141 will be described.

  A suction port 142 a is perforated on the side of the filling side valve unit 142. A passage extending from the suction port 142 a to the inside is formed as a through hole, intersects and communicates with the opening 142 b inside the filling side valve unit 142, and the opening at the other end is closed by the outer wall of the chamber 103. The suction port 142a is connected to a hose that supplies paint from a tank described later.

  The discharge-side valve unit 141 is also provided with the same through-hole structure (141a) as described above, but the opening corresponding to the suction port 142a of the filling-side valve unit 142 is closed by a blind lid 141a ′. Of the hole structure (141a), only the portion connecting the opening 141b inside the discharge side valve unit 141 and the paint path 103c drilled on the side of the chamber 103 functions as a paint passage.

  A paint path 142c is perforated in the large diameter portion in front of the opening 142b of the filling side valve unit 142, and communicates with the paint path 103b perforated on the side of the chamber 103. The paint path 103 b communicates with the pressure chamber 103 a of the chamber 103.

  A through hole similar to the paint path 142c is provided at the same position and in the same structure on the discharge side valve unit 141 side, and this through hole functions as the paint path 141c. The paint path 141 c communicates the large diameter portion in front of the opening 141 b of the discharge side valve unit 141 with the paint path 103 d of the chamber 103.

  The paint supply route in the above structure is summarized as follows. That is, the paint supply path in the structure of FIG. 3 continues from the suction port 142a to the needle valve 109 to the opening 142b to the paint path 142c (the charging side valve unit 142) to the paint path 103b to the pressure chamber 103a. The paint supply path downstream from the pressure chamber 103a is paint path 103c (chamber 103) to paint path 141a to needle valve 109 to opening 141b to paint path 141c (to discharge side valve unit 141) to paint path 103d. It continues from the nozzle port 103e (above the chamber 103 front) to the dispenser chip 180.

  Of the above, the linear distance from the pressure chamber 103a functioning as the paint supply means to the dispenser chip 180 functioning as the paint application means for applying the paint to the object to be applied is determined by considering the head pressure of the servo gun 100. The length is such that the paint does not drip from the dispenser chip 180 no matter how the posture is controlled, for example, about 30 cm or less, more preferably about 10 cm or less. However, it goes without saying that a person skilled in the art can appropriately change the design of the total length of the paint path from the pressure chamber 103a to the dispenser chip 180 in accordance with the viscosity of the paint.

  The maximum amount of paint retained in the pressure chamber 103a functioning as the paint supply means obtained when the piston 102 is retracted to the initial position on the left side of FIG. 3 is the same as that described above, that is, the position of the servo gun 100. Even if it controls in this way, it is set as the capacity | capacitance which a coating material does not spill from the dispenser chip | tip 180, for example, about 50 cc or less, More preferably, about 5 cc or less However, it goes without saying that the paint holding capacity of the pressure chamber 103a can be appropriately changed by those skilled in the art according to the viscosity of the paint.

  Opening and closing of the needle valves 109 and 109 of the filling side valve unit 142 and the discharge side valve unit 141 are operated by the air cylinder units 152 and 151 via the shafts 110 and 110, respectively.

  The air cylinder units 152 and 151 have the same structure, and each has an air cylinder tube 111 as an outer shell. The air cylinder tube 111 is fixed to the side of the chamber 103 by screws or the like.

  An air cylinder shaft 127 is supported inside the air cylinder tube 111 so as to be slidable in the left-right direction in the figure. The front portion (the right side in the figure) of the air cylinder shaft 127 is supported by the air cylinder tube 111 via the O-ring 124.

  The front end portion of the air cylinder shaft 127 is coupled to a shaft 110 that operates the filling side valve unit 142 and the discharge side valve unit 141 via stud bolts and nuts.

  An air cylinder piston head 112 is fixed to the rear end portion (left side in the figure) of the air cylinder shaft 127, and the air cylinder piston head 112 is urged by a spring 128 to the left in the figure. The rear end portion (the left side in the figure) of the air cylinder tube 111 is sealed with an air cylinder head cover 113 via an O-ring 125.

  Air for advancing the air cylinder piston head 112 is sent into the air cylinder tube 111 from a port 151 a or 152 a provided in the air cylinder head cover 113.

  When air is not being supplied, the biasing force of the spring 128 is used, and when air for retreating the air cylinder piston head 112 is supplied from the port 152b or 151b on the side of the air cylinder tube 111, this is applied. The air cylinder piston head 112 is retracted to the left in the figure by the air pressure and the urging force of the spring 128, and the needle valve 109 of the charging side valve unit 142 or the discharge side valve unit 141 is pulled to the left in the figure, and the paint passage Is closed.

  On the other hand, when air is supplied from the port 152a or 151a and the rear portion (the left side in the figure) of the air cylinder piston head 112 inside the air cylinder tube 111 is pressurized, the air cylinder piston head 112 moves forward (to the right in the figure). Then, the needle valve 109 of the filling side valve unit 142 or the discharge side valve unit 141 is pushed rightward in the drawing, and the paint passage is opened.

  The supply of air to the air cylinders 151 and 152 is controlled by a solenoid valve described later, and the opening and closing of the filling side valve unit 142 or the discharge side valve unit 141 can be controlled independently. The mode of opening / closing control of each valve unit will be described in detail later.

  Next, a structure for controlling the pressure in the pressure chamber 103a by the piston 102 will be described.

  A servo motor 114 is attached to the rear end portion of the housing 101, and the drive shaft of the servo motor 114 is coupled to the rear end portion of the ball screw 117 via the coupling 115. The ball screw 117 is supported through a support unit 116 at a central position of shafts 126, 126 connecting the housing 101 and the chamber 103.

  A bolt 119 with a hole is formed at the tip of the ball screw 117 and is screwed into a ball guide 118 cut into the piston 102.

  With the above structure, when the ball screw 117 is rotated counterclockwise or clockwise by the servo motor 114, the piston 102 moves forward or backward, and thereby the head of the piston 102 enters or exits the pressure chamber 103a of the chamber 103. The pressure chamber 103a can be pressurized or depressurized.

  In this embodiment, the position of the piston 102 can be detected by an optical fiber sensor. A sensor dog 136 is erected at a rear end portion of the piston 102 in a direction perpendicular to the paper surface. The optical fibers 138a and 138b on the light projecting side and the light receiving side of the optical fiber sensor are arranged so that the optical axis intersects with the region through which the sensor dog 136 passes. The optical fibers 138a and 138b are fixed to the housing 101 by screwing or the like via fiber brackets 134 and 135.

  The housing 101 is mounted with a mounting bracket 138 for mounting an optical fiber sensor amplifier unit (not shown). The optical fibers 138a and 138b on the light projecting side and the light receiving side are connected to an optical fiber sensor amplifier unit mounted on the mounting bracket 138, and detection and display control are performed by the amplifier unit. This type of amplifier unit is provided with LED indicators that display the detection status of dogs passing between optical fibers, in addition to operating means for controlling sensitivity settings, etc. By attaching to 100, the LED indicator of the amplifier unit can function as an indicator of the operating state of the piston 102.

  The output of the optical fiber sensor can also be used for detecting the initial position of the piston 102 in the control described later.

  Next, the overall configuration of the coating system of this embodiment will be described with reference to FIG.

  In FIG. 2, the servo gun 100 described with reference to FIG. 3 is supported at the arm tip of the robot arm 200. The robot arm 200 is a known robot arm 200 capable of, for example, three-axis control (for example, table rotation two axes, arm rotation one axis). In addition, depending on the coating application, a traveling type such as a traveling type or a different number of axes may be used.

  In the automatic painting process, the servo gun 100 is operated by the robot arm 200 to bring the dispenser chip 180 at the tip of the servo gun 100 into contact with the painting object (not shown) and to cause relative movement between the painting object and the servo gun 100. To do. In this way, a predetermined paint application pattern can be formed on the object to be coated. By such a painting process, it is possible to express straight lines, curves, characters, images, fills, and the like.

  The control of the robot arm 200 and the control related to paint filling and application of the servo gun 100 are performed by the control unit 900.

  Control unit 900 can be configured using, for example, robot operation panel 300 and PLC 400. In the following, an example in which the control unit 900 is configured using the robot operation panel 300 and the PLC 400 will be described. Of course, the control unit 900 is a single control unit that controls the robot arm 200 and paint filling and coating control of the servo gun 100. You may comprise by.

  In this embodiment, the operation or programming of the robot arm 200 is performed via the robot operation panel 300. In addition to operating means for operating the robot arm 200, the robot operation panel 300 is provided with operating means for designating the operation timing of the servo gun 100 configured using, for example, function keys.

  On the other hand, the painting operation by the servo gun 100 is controlled by a PLC (Programmable Logic Controller) 400.

  In the present embodiment, the robot operation panel 300 moves the servo gun 100 at the tip of the arm with the robot arm 200, brings the dispenser chip 180 of the servo gun 100 into contact with the object, and applies the paint along a predetermined application pattern (shape). Programming like so.

  At the same time, the PLC 400 is applied by the servo gun 100 at each timing of starting application by bringing the tip of the dispenser chip 180 into contact with the object on the robot operation panel 300 and ending the application by separating the tip of the dispenser chip 180 from the object. Control signals are output from the I / O input / output board 301 and the analog output board 302 of the robot operation panel 300 so that the operation can be controlled.

  In this embodiment, the I / O input / output board 301 of the robot operation panel 300 controls the discharge valve ON / OFF signal, the filling valve ON / OFF signal, the suction signal, the application signal, the speed control signal, the position control signal, and the like. The signal is output to the I / O input port 403 of the PLC 400.

  Further, a servo speed command signal (voltage signal) is output from the analog output board 302 of the robot operation panel 300 to the analog input port 405 of the PLC 400.

  The PLC 400 is configured by combining a PC (personal computer) 402 with a power supply 401, an I / O input port 403, an I / O output port 404, an analog input port 405, and a positioning unit 406.

  Further, predetermined control for performing three-axis (or more than one axis) control of the robot arm 200 from the I / O output port 404 of the PLC 400 to the I / O input / output board 301 of the robot operation panel 300. By inputting the signal, the operation of the robot arm 200 can be controlled from the PLC 400 side via the robot operation panel 300.

  By configuring the control unit 900 as described above, for example, after programming the operation of the robot arm 200 that operates the servo gun 100 and the start and end timing of coating of the servo gun 100 using the robot operation panel 300, for example. The programming data is recorded on the PLC 400 side and reproduced later. That is, based on the programming data recorded by the PLC 400, the operation of the robot arm 200 is controlled via the robot operation panel 300, and the painting operation of the servo gun 100 is performed. By controlling it, an automatic coating process can also be performed.

  Next, the coating control system of the servo gun 100 will be described in further detail.

  As described above, the servo gun 100 is provided with the pressure chamber 103a for pressurizing the paint, and the piston 102 can control the pressure of the paint in the pressure chamber 103a.

  The piston 102 is driven by a servo motor 114, and the servo motor 114 is controlled by a positioning unit 406 of the PLC 400 via a servo controller 407.

  The pressure of the paint in the pressure chamber 103a is detected by the pressure sensor head 191. The detection state of the pressure sensor head 191 is converted into a digital signal by the pressure sensor unit 193 and input to the PLC 400 via the I / O input port 403.

  Therefore, the PLC 400 determines that the paint pressure in the pressure chamber 103a is a predetermined value based on the detection value obtained from the pressure sensor head 191 during the paint application period or a pre-pressure (pre-pressurization) period (described later) during movement of the servo gun 100. Thus, feedback control can be performed by controlling the position of the piston 102 via the servo motor 114.

  Further, the servo gun 100 is provided with a filling side valve unit 142 and a discharge side valve unit 141 for filling the pressure chamber 103a with paint. The opening and closing of the filling side valve unit 142 and the discharge side valve unit 141 are controlled by air cylinder units 152 and 151, respectively.

  The driving of the air cylinder units 152 and 151 is controlled by a charging valve solenoid valve 162 and a discharge valve solenoid valve 161, respectively. The charging valve solenoid valve 162, the discharge valve solenoid valve 161, and the air cylinder units 152 and 151 are connected by air pipes for controlling the forward and backward movements of the air cylinder piston head 112, respectively.

  The charging valve solenoid valve 162 and the discharge valve solenoid valve 161 are controlled by signals from the I / O output port 404 of the PLC 400.

  With such a configuration, the PLC 400 allows the charging valve solenoid valve 162 and the discharge valve solenoid valve 161 to open and close the filling side valve unit 142 and the discharge side valve unit 141 according to the progress of the painting sequence. The air supply is controlled via

  Air necessary for driving the air cylinder units 152 and 151 is supplied through an intake port 501 from an external compressor (not shown) or the like. A mist separator 502 for removing foreign matters such as fine particles, oil, and moisture is disposed in the pipe immediately after the suction port 501.

  In this embodiment, the filling valve solenoid valve 162 and the discharge valve solenoid valve 161 are configured to control the forward and backward movements of the air cylinder piston head 112 of the air cylinder units 152 and 151 in a two-port manner. Although shown, the port configuration of these solenoid valves / air cylinder units is not limited to the illustrated embodiment.

  The paint supplied to the servo gun 100 is accommodated in the closed tank 700 and constantly stirred by the stirrer 600 in order to prevent uneven viscosity and solidification. As the stirrer 600, an arbitrary stirring method such as a magnetic stirrer can be used.

  The inside of the hermetic tank 700 is pre-pressurized with air whose flow rate is controlled to be constant via the precision regulator 504 via the mist separator 502.

  One end of a paint tube 701 made of nylon or the like is immersed in the paint in the sealed tank 700, and the other end of the paint tube 701 is connected to the charging side valve unit 142 suction port 142a.

  The paint is a pigment dissolved in various solvents such as white gasoline, alcohol and thinner, and any paint having any composition can be used as long as it can reach the tip of the application body 181 of the dispenser chip 180 by capillary action. it can.

  An air operation regulator 192 for controlling the flow rate of the paint to be constant is disposed at an intermediate portion of the paint tube 701. Control air whose flow rate is controlled to be constant is supplied to the air operation regulator 192 via the mist separator 502 and further via the precision regulator 503. In this way, the supply flow rate of the paint to the servo gun 100 is controlled to be constant.

  Further, in this embodiment, a CCD camera 800 that operates so as to follow the application locus of the servo gun 100 is mounted on the robot arm 200 together with the servo gun 100. A structure for mounting the CCD camera 800 will be described later with reference to FIGS.

  The image signal output of the CCD camera 800 is input to the analog input port 405 of the PLC 400. The above-described image processing unit 903 is configured by a hardware circuit (not shown) that processes an input image of the analog input port 405, or an image processing program of the PLC 400.

  The paint and air pipes (tubes) or wires are bundled by the Saya pipe fitting 700a and piped to the servo gun 100.

  4 and 5 show an example of a structure for mounting the CCD camera 800 on the robot arm 200 together with the servo gun 100 and for displacing the CCD camera 800 so as to follow the coating operation of the servo gun 100. FIG.

  The servo gun 100 configured as described above is fixed to a tool bracket 1001 having a substantially L-shaped cross-sectional structure via a bracket 1002 by a method such as bolting (1002a). A dispenser chip 180 having the above-described application body 181 is attached to the tip of the servo gun 100.

  The CCD camera 800 is fixed together with the illumination 801 on the mount 1004. The mount 1004 is fixed to the arm 1003 via an L-shaped support tool 1004a. The arm 1003 is fixed to the shaft 1006 via a metal collar 1016 by a method such as welding or bonding.

  The shaft 1006 is a swing center of the CCD camera 800 and is pivotally supported by the bearing holder sets 1012 and 1013 so as to coincide with a straight line passing through substantially the center of the dispenser chip 180 that is an application unit of the servo gun 100.

  With such a configuration, the CCD camera 800 is supported so as to be able to turn to different arbitrary rotational positions centering on a straight line passing through substantially the center of the dispenser chip 180 that is the application means of the servo gun 100, and on the object to be coated. The photographing optical axis of the CCD camera 800 can be moved to any one of the rotational positions by a servo motor (1008 below) so as to photograph the coating pattern of paint immediately after the formation.

  Thereby, according to the application direction of the coating material, the CCD camera 800 can be moved to a tracking position for photographing the coating pattern of the coating material just formed on the coating object so that the CCD camera 800 can move. The formation state of the coating pattern of the paint can be fed back to the contact coating operation.

  Both ends of the shaft 1006 are fixed and secured by bearing nuts 1014 and 1014 outside the bearing holder set 1012 and 1013. The bearing holder set 1012 at the rear end is fixed inside a counterbore hole provided at the rear end of the tool bracket 1001, and the bearing holder set 1013 at the front end is supported by a support member (not shown) fixed to the tool bracket 1001. To do.

  A spur gear 1010 is fixed to the center of the shaft 1006, and the spur gear 1010 meshes with a spur gear 1009 driven by a servo motor 1008. The servo motor 1008 is fixed on the tool bracket 1001 via the mounting bracket 100a, and the spur gears 1009 and 1010 are accommodated in the gear cover 1007.

  The swing position of the CCD camera 800 indicated by the solid line in FIGS. 4 and 5 is, for example, a home position, and this swing position is detected by a proximity sensor 1015 including an optical sensor, a magnetic sensor, and the like.

  What is indicated by an alternate long and short dash line 800a in FIG. 5 is a rotation locus of the photographing optical axis of the CCD camera 800 around the shaft 1006. The CCD camera 800 can turn around the home position, for example, within a range of ± 120 degrees shown in the figure by driving the servo motor 1008, and can stop at an arbitrary position.

  Assuming that the dispenser chip 180 of the servo gun 100 is drawn in any direction within the plane of FIG. 5, the CCD camera 800 should preferably be configured so that it can capture the coating trajectory of all paint immediately after drawing. Thus, the turning range of the CCD camera 800 or the shooting angle of view of the CCD camera 800 is selected so as to satisfy this shooting condition.

  In FIG. 4, reference numeral 191 denotes the pressure sensor head described above. Further, the U-shaped metal fitting 1020 shown in FIG. 5 is a structural member that functions as a reinforcement and a turning guide for the CCD camera 800.

  The CCD camera 800 can take an image of several to several tens of frames per second, for example, and the image signal output from the CCD camera 800 is input to the analog input port 405 of the PLC 400 as described above. However, the image signal output from the CCD camera 800 may be input to the PLC 400 in a still image / moving image data format such as JPEG or MPEG.

  Further, drive control information of the servo motor 1008 for controlling / determining the attitude of the CCD camera 800 is supplied, for example, from a servo controller 407 (FIG. 2) of the PLC 400 via a route (not shown) or via the robot control panel 301. It is assumed that it is supplied as one of the control signals for the robot arm. Of course, the servo motor 1008 rotates the shaft 1006 via the spur gears 1009 and 1010 according to the input drive control information, and rotates the CCD camera 800 to the rotation position designated by the input drive control information. It shall be comprised so that it can be made to do.

Next, the automatic coating (automatic application) operation in the above configuration will be described. Here, basic control (lower level control) of the servo gun 100 will be described with reference to FIGS. 6 to 8, and subsequently, application (drawing) control (upper level) performed using images taken by the CCD camera 800 with reference to FIGS. 10 to 12. FIG. 6 to FIG. 8 mainly show the basic part of the automatic painting control implemented in the above configuration, particularly the paint supply control belonging to the lower level. Here, the dispenser chip 180 of the servo gun 100 is brought into contact with the object to be painted under the control of the robot arm 200, or further moved along the object to be painted according to the intended painting pattern, separated from the object to be painted, and on standby Since the control on the side of the robot arm 200 such as moving to the (pause) position is known, the description thereof is omitted.

  The control procedures shown in FIGS. 6 to 8 can be stored in the storage means of the control unit 900 as an automatic painting control program executed by the control unit 900 of FIG. For example, in FIG. 2, when the PLC 400 controls the entire operation including the operation of the robot arm 200 and the painting operation by the servo gun 100, the control procedure described later is stored in storage means (not shown) such as an HDD or a flash memory of the PLC 400. Can be stored.

  The filling procedure in FIG. 6 shows the flow of the control procedure of the filling process for filling the pressure chamber 103a with the paint. The filling procedure of FIG. 6 is not applied, for example, while the dispenser tip 180 of the servo gun 100 is separated from the object to be coated, or the servo gun 100 is moved to a predetermined pause / standby position by the robot arm 200. It can be implemented at any timing of the period.

  When the filling process of FIG. 6 is performed, the stirrer 600 is driven to stir the sealed tank 700, and the solenoid valves 161 and 162, the air operated regulator 192, and the like can be operated. A predetermined pressure of air is supplied to the suction port 501 from the compressor of the compressor (the same applies to the discharge / coating process described later).

  In step S301 in FIG. 6, first, the discharge valve unit 141 is closed (OFF) via the discharge valve solenoid valve 161 and the air cylinder unit 151. In step S302, the filling valve solenoid valve 162 and the air cylinder are closed. The filling side valve unit 142 is opened (ON) through the unit 152.

  Since the operations of the solenoid valves 161 and 162, the air cylinder units 151 and 152, and the valve units 141 and 142 are obvious from the above description, the charging side valve unit 142 and the discharge unit are simply described below in order to avoid complexity. Only the operation of the side valve unit 141 will be described.

  In steps S302 and S303, the piston 102 is moved to the initial position on the left side of FIG. 3 via the servo motor 114 and the ball screw 117. At this time, since the filling side valve unit 142 is open and the discharge side valve unit 141 is closed, the paint is filled into the pressure chamber 103a by the movement of the piston 102 to the initial position.

  As described above, the paint passes from the sealed tank 700 through the paint tube 701 to the suction port 142a, the needle valve 109, the opening 142b, the paint path 142c (the charging side valve unit 142), the paint path 103b, and the pressure chamber 103a. It is filled in the following path.

  The current position of the piston 102 is detected by monitoring the output of the encoder of the servo motor 114 or by monitoring the output of the optical fiber sensor.

  When it is detected in step S302 that the piston 102 has retracted to the predetermined initial position, the process proceeds to step S304, and the charging side valve unit 142 is closed (OFF).

  Subsequently, in steps S305 to S307, the paint in the pressure chamber 103a is pre-pressurized (preliminary pressurization) to a predetermined pressure with the filling-side valve unit 142 and the discharge-side valve unit 141 closed.

  In step S305, the paint pressure in the pressure chamber 103a is detected via the pressure sensor head 191 and the pressure sensor unit 193, and it is detected whether or not the pressure value is (substantially) equal to a predetermined preload target value.

  If the paint pressure in the pressure chamber 103a is higher than the predetermined preload target value in step S305, the piston 102 is retracted in step S306 via the servo motor 114 and the ball screw 117. If it is lower than the predetermined preload target value, step S307 is performed. The piston 102 is moved forward.

  Since the operations of the servo motor 114, the ball screw 117, and the piston 102 are obvious from the above description, only the operation of the piston 102 will be described below in order to avoid complexity.

  The preload adjustment process in steps S305 to S307 is continued until the completion of the filling process is detected in step S308.

  The completion of the filling process detected in step S308 is that the condition for starting the painting process is satisfied, for example, the dispenser chip 180 of the servo gun 100 touches the object to be painted or has been moved to the object to be painted. It can be determined by detecting the above.

  As shown in FIG. 6, the piston 102 is moved to the initial position during the non-application period to fill the pressure chamber 103a with a predetermined volume of paint, and the filling side valve unit 142 and the discharge side valve unit 141 are closed. In this state, the paint in the pressure chamber 103a can be adjusted to a predetermined preload pressure. In this way, by adjusting the paint pressure in the pressure chamber 103a to a predetermined preload value during the non-application period, the dispenser chip 180 can be applied at the desired paint pressure immediately after the dispenser chip 180 is brought into contact with the object to be coated. The paint can be supplied to 180, and the paint can be applied efficiently.

  FIG. 7 shows a flow of application (discharge) processing performed by bringing the dispenser chip 180 of the servo gun 100 into contact with an object to be coated. The application (discharge) process of FIG. 7 can be started, for example, from the time when the dispenser chip 180 is brought into contact with the object to be coated (or is brought close to the vicinity of the object to be coated).

  In step S401 of FIG. 7, the charging side valve unit 142 is first closed (OFF), and in step S402, the discharge side valve unit 141 is opened (ON). The state of each valve unit is held until the end of the coating process is detected in step S406.

  Thereby, the paint supply path downstream from the pressure chamber 103a, that is, the paint path 103c (above chamber 103) to the paint path 141a to the needle valve 109 to the opening 141b to the paint path 141c (to the discharge side valve unit 141) to the paint path 103d. -Nozzle port 103e (above chamber 103 front part)-Dispenser chip 180 and the supply path which continues are formed.

  In step S403, the paint pressure in the pressure chamber 103a is detected via the pressure sensor head 191 and the pressure sensor unit 193, and it is detected whether or not the pressure value is (substantially) equal to a predetermined target value. The pressure target value at the time of application may be the same as the previous preload target value, or may be set higher or lower than the previous preload target value depending on various conditions.

  If the paint pressure in the pressure chamber 103a is higher than the predetermined preload target value in step S403, the piston 102 is retracted in step S404 via the servo motor 114 and the ball screw 117, and if lower than the predetermined preload target value, step S405 is performed. The piston 102 is moved forward.

  In this way, in the coating process, the paint pressure in the pressure chamber 103a is feedback-controlled so as to become a predetermined pressure target value, and there arises a disadvantage that the paint hangs down from the application body 181 at the tip of the dispenser chip 180. In addition, the paint can be applied without causing inconveniences such as blurring and uneven application due to insufficient supply of the paint.

  That is, the piston 102 can be advanced by an amount corresponding to the amount of pressure that is applied and consumed from the application body 181 at the tip of the dispenser chip 180, and the piston 102 is advanced too much. If the paint pressure becomes too high, the piston 102 can be retracted. In addition, variations in paint pressure that may occur due to such feedback control or the posture of the servo gun 100 can be compensated, and the pressure immediately before the application body 181 at the tip of the dispenser chip 180 is substantially constant suitable for paint application. The pressure can be controlled.

  In step S406, the end of the application (discharge) process is detected. The end of the application (discharge) process can be determined by detecting a condition such that the dispenser chip 180 finishes drawing a predetermined pattern on the object to be coated, and the dispenser chip 180 is separated from the object to be coated. When the end of the application (discharge) process is detected, the discharge side valve unit 141 is closed (OFF) in step S407, and the entire application (discharge) process is ended. When the application (discharge) process is completed, for example, the process can immediately shift to the filling process of FIG.

  As described above, during application of the paint, the paint pressure in the pressure chamber 103a of the chamber 103 is controlled to approach a predetermined target value, that is, the paint pressure in the pressure chamber 103a is controlled to be within a predetermined range. Thus, the coating material can be prevented from dripping from the dispenser chip 180, and the coating liquid can be applied to the coated object without contaminating the work environment and unnecessary portions of the coated object. In addition, since the paint can be supplied to the dispenser chip 180 with a constant paint supply amount, it is possible to accurately express straight lines, curves, characters, images, painting, and the like.

  FIG. 8 shows a general flow of automatic painting control, particularly control of the lower part. As shown in the figure, the processing of FIG. 8 is performed in step S501 depending on whether the application (discharge) section is performed or not (FIG. 7) or in step S503. 6). The processing in steps S501 to S503 is continued until the end of the entire automatic painting process is detected in step S504.

  The determination of whether or not it is the application (discharge) section in step S501 is performed by detecting conditions such as the dispenser chip 180 of the servo gun 100 touching the object to be coated or moved to the vicinity of the object to be coated. be able to.

  Further, the end determination of the entire automatic painting process in step S504 can be performed by detecting that all the painting patterns have been drawn on the painting object.

  As shown in FIG. 8, by performing the filling process in a non-application period other than the time of applying the paint to the object to be applied, the paint can be efficiently filled (supplemented) into the chamber 103 of the servo gun 100.

  On the other hand, FIGS. 10 to 12 show the flow of higher-level drawing control executed by the control unit 900. The lower-level routines shown in FIGS. 6 to 8 are called as necessary according to the flow of control shown in FIGS. 10 to 12 can be stored in a storage unit (not shown) such as an HDD or a flash memory of the PLC 400 as a program executed by the control unit 900.

  10-12, it is assumed that the drawing program (901: FIG. 1) is configured using, for example, data representation based on the vector representation as shown in FIG. As described above, the data representation as shown in FIG. 9 is merely an example.

  FIG. 10 shows a control in which the control unit 900 that executes the drawing program detects the direction change of the drawing and causes the CCD camera 800 to follow the drawing.

  In step S601 of FIG. 10, one drawing command CMDn (FIG. 9) is extracted from the drawing program (901) developed on the HDD or memory (not shown). The drawing program (901) is stored in a storage format such as a linked list. In step S601 of the program, the drawing command CMDn next to the drawing command CMDn-1 extracted last time is extracted. To do.

  In step S602, the extracted drawing command CMDn is analyzed, and it is determined whether or not a direction change occurs in the drawing direction by executing the drawing command. As shown in FIG. 9, the drawing command CMDn is a vector expression and includes information on the moving direction. Compared with the previously executed drawing command CMDn-1, the drawing command CMDn is executed in the direction of the drawing direction. It can be determined whether or not conversion occurs. At this time, when information on the direction from the start point Pn to the end point Pn + 1 and the direction change flag are stored in the drawing command CMDn as described above, it is easy to determine whether or not the direction change occurs in the drawing direction using these. Can be determined.

  If it is determined in step S602 that no direction change occurs, drawing control is performed in step S604 described later. When the process proceeds from step S602 to step S604, the turning position of the conventional CCD camera 800 and the drawing control conditions (step S604, see FIGS. 11 to 12) are used.

  If it is determined in step S602 that the direction change occurs in the drawing direction by executing the drawing command CMDn, the tracking position of the CCD camera 800 is calculated in step S603. As shown in FIGS. 4 and 5, the CCD camera 800 turns through a servo motor 1008 around a turning axis that coincides with the center of the dispenser chip 180, for example, 120 ° + 120 °, and stops at an arbitrary position. be able to.

  Since the moving direction of the dispenser chip 180 operated by the robot arm 200 can be calculated from the drawing command CMDn, in this step S603, a swiveling position that is 180 ° different from the moving direction of the dispenser chip 180 is set as the swiveling position of the CCD camera 800. Just choose. In the configuration shown in FIG. 5, the CCD camera 800 cannot swivel within a 360 ° range centered on the dispenser chip 180, and therefore the CCD camera cannot be selected if a swiveling position that is 180 ° different from the moving direction of the dispenser chip 180 cannot be selected. It is assumed that an optimum position where the application locus formed by the dispenser chip 180 can be captured within the range of the angle of view of 800 is selected as the turning position of the CCD camera 800.

  In step S605, the robot arm 200 is controlled to change the drawing direction. At the same time, the servo motor 1008 is controlled to rotate the CCD camera 800 to the turning position (following position) calculated in step S603, and the drawing control in step S604 is started.

  In the drawing control in step S604, information about the start point Pn (Xn, Yn, Zn), end point Pn + 1 (Xn + 1, Yn + 1, Zn + 1), etc. stored in the drawing command CMDn, information about the target value of the line width wi, and density di, Alternatively, the drawing operation represented by the drawing command CMDn by the dispenser chip 180 of the servo gun 100 by controlling the robot arm 200 while executing the above-described lower-level application control based on information on the target value such as writing pressure. To do.

  Further, the drawing control in step S604 can be executed by calling the drawing control as shown in FIGS. 11 to 12 using image information captured by the CCD camera 800.

  The drawing control in FIG. 11 is based on the image information captured by the CCD camera 800 and controls the line width of the coating pattern drawn by the dispenser chip 180 of the servo gun 100 to match a certain target value (constant line width control). In addition, the drawing control of FIG. 12 is based on the image information captured by the CCD camera 800 so that the paint concentration width of the coating pattern drawn by the dispenser chip 180 of the servo gun 100 matches a certain target value. Yes (constant concentration control).

  The constant line width control in FIG. 11 is performed while drawing is being executed. That is, in step S701 of FIG. 11, the dispenser chip 180 of the servo gun 100 is brought into contact with the object to be coated, and it is determined whether or not drawing is performed by applying paint. Only when drawing is being performed, the processing after step S703 is performed. Run. If the drawing is not in progress, the process returns to the drawing routine (step S604) that called the constant line width control (step S702).

  If drawing is being performed in step S701, the line width w (actual value) of the current application locus is acquired from image information captured by the CCD camera 800 in step S703. The acquisition of the line width w (actual value) is performed by the image processing unit 903 (FIG. 1).

  Subsequently, in step S704, it is determined whether or not the line width w (actual value) of the application locus is equal to (or substantially equal to within a certain range) the line width target value wi. If step S704 is affirmed, the process returns to the original drawing routine without executing line width control any more (step S707).

  If the line width w (actual value) of the application locus is smaller than the target value wi of the line width in step S704, the line width w (actual value) of the application locus is the target value wi of the line width. If it is larger, the process branches to step S706.

  In step S705, drawing control is performed so that the current line width w becomes larger (line width enlargement control). In step S706, drawing control is performed so that the current line width w becomes smaller (line width reduction control).

  Various methods are conceivable for the line width enlargement control (S705) and the line width reduction control (S706).

  For example, when the application body 181 of the dispenser chip 180 is made of a material having a certain degree of flexibility as described above, the applied line width can be changed by the pressure (writing pressure) that presses the dispenser chip 180 against the application object. . Therefore, in this case, in the line width enlargement control (S705), the writing pressure of the dispenser chip 180 is increased, and in the line width reduction control (S706), the writing pressure of the dispenser chip 180 is reduced. The desired line width adjustment control of each step can be executed. The writing pressure of the dispenser chip 180 can be controlled, for example, by adjusting the distance between the servo gun 100 that holds the dispenser chip 180 and the object to be coated.

  Further, when the cross-sectional shape of the tip of the application body 181 of the dispenser chip 180 is rectangular, the width of the line of the application pattern is adjusted by adjusting the rotation angle around the axis of the tip of the dispenser chip 180 with respect to the drawing direction. Can be feedback-controlled (constant line width control) so as to match (or approach) a certain target value. Further, in the structure in which the length of the application body 181 of the dispenser chip 180 is changed from one end to the other end, the width of the line of the application pattern can also be adjusted by adjusting the inclination angle of the dispenser chip 180. Feedback control (constant line width control) can be performed so as to match (or approach) a certain target value. However, in these controls, as long as the structure shown in FIGS. 4 and 5 is followed, the photographing range of the CCD camera varies. Therefore, when adjusting the rotation angle or the inclination angle of the dispenser chip 180 around these axes, Control is performed to correct the turning position of the CCD camera in accordance with the adjustment amount.

  Note that there is a limit to the control amount such as the above-described writing pressure, the rotation angle around the axis of the dispenser chip 180, and the tilt angle. For example, if the writing pressure is excessive, the dispenser chip 180, the servo gun 100, the robot arm 200, the mechanism for coupling them, and the object to be coated may be damaged. If it exceeds a certain range, it may become impossible to apply. Therefore, when the control amount related to the operation of the servo gun 100 and the robot arm 200 reaches a certain limit value, it is limited not to perform any further feedback control, or to generate sound or light to the user ( Naturally, the warning information may be generated by using a sound source, a speaker, a display, and the like. In this way, damage to the mechanism can be prevented and the user can be notified that an abnormality has occurred.

  As described above, by performing the constant line width control of FIG. 11, it is possible to control the line width of the coating pattern to (almost) coincide with a certain target value based on image information captured by the CCD camera 800. it can.

  On the other hand, the overall flow of the constant density control of FIG. 12 is almost the same as the control of FIG. In FIG. 12, the same step numbers are used for steps equivalent to FIG.

  The constant density control in FIG. 12 is also performed while drawing is being executed. That is, in step S701 of FIG. 12, the dispenser chip 180 of the servo gun 100 is brought into contact with the object to be coated, and it is determined whether or not drawing is performed by applying paint. Only when drawing is being performed, the processing after step S803 is performed. Run. If drawing is not in progress, the process returns to the drawing routine (step S604) that called this constant density control (step S702).

  If drawing is in progress in step S701, the current application locus density d (actual value) is acquired from the image information captured by the CCD camera 800 in step S803. The density d (actual value) is acquired by the image processing unit 903 (FIG. 1).

  In step S804, it is determined whether the density d (actual value) of the application locus is equal to the density target value di (or approximately equal within a certain range). If step S804 is affirmed, the process returns to the original drawing routine without executing density control any more (step S807).

  If the density d (actual value) of the application trajectory is smaller than the target density di in step S804, the process goes to step S805, and the density d (actual value) of the application trajectory is larger than the target density di. Branches to step S806.

  In step S805, drawing control is performed so that the current density d becomes larger (density increase control). In step S806, drawing control is performed so that the current density d becomes smaller (density reduction control).

  Various methods can be considered for the concentration increase control (S805) and the concentration decrease control (S806). For example, as described above, the pressure chamber of the chamber 103 of the servo gun 100 that is feedback-controlled via the pressure sensor head 191. By changing the target value of the paint pressure in 103a, the amount of paint supplied to the dispenser chip 180 can be increased or decreased within a minute range.

  Of course, the adjustment of the supply amount of the paint needs to be performed within a range in which the extra paint does not spill from the dispenser chip 180 as described above. In particular, in the step of increasing the concentration (step S805), When the paint pressure has already reached the limit of the range in which the paint does not sag, it is necessary to incorporate a restriction routine that does not further increase the supply amount of paint. In addition, when this restriction routine is activated, it is likely that an error that does not satisfy the desired operating conditions of the system has occurred. May generate warning information.

  As described above, by performing the constant density control of FIG. 12, feedback control is performed so that the density of the coating pattern coincides (or approaches) the constant target value based on the image information captured by the CCD camera 800. can do.

  11 and 12, the constant line width control and the constant density control are illustrated as independent control procedures. Of course, both of these controls can be executed. In that case, for example, it is conceivable to insert a routine constituted by steps S803 to S806 in FIG. 12 immediately before step S707 in FIG.

  As described above, in this embodiment, the application locus of the servo gun 100 is photographed by the CCD camera 800 that is displaced so as to follow the application locus of the servo gun 100 operated by the robot arm 200. Based on the image information captured by the CCD camera 800, information relating to the contact application state, that is, information relating to the application pattern formation state of the application liquid, for example, information relating to the line width and density, is detected. By performing feedback control, it is possible to execute a high-precision and high-quality contact coating operation according to a desired coating condition.

  In the above, an example has been described in which the control unit 900 that executes the drawing program detects the direction change of the drawing and causes the CCD camera 800 to follow the drawing. However, control means for controlling the attitude of the CCD camera 800 may be provided on the robot arm 200 side. In this case, a command transmitted from the control unit 900 to the robot arm 200 is analyzed, a change in the movement direction of the tip of the robot arm is detected, and a control circuit for controlling the posture of the CCD camera 800 is provided to the robot arm 200. Just put it.

  In the above description, the coating liquid is taken as an example of the coating liquid to be applied to the object to be coated (application object), and the embodiment relating to the automatic coating system for coating the object to be coated (application object) by contact coating has been shown. However, it is needless to say that the above configuration can be similarly applied even when the coating liquid is other than a paint, for example, any chemical liquid. In that case, if the above “paint” is appropriately read as “application liquid”, “coating object” as “application object”, “painting” as “application”, etc., the above description will remain as it is. It is also valid when using.

It is the block diagram which showed notionally the structure of the coating device which employ | adopted this invention. It is explanatory drawing which showed the system configuration | structure of the coating device which employ | adopted this invention. It is sectional drawing which showed the structure of the servo gun of the coating device which employ | adopted this invention. It is sectional drawing which showed the structure around the servo gun and CCD camera of the coating device which employ | adopted this invention. It is the front view which showed the structure around the servo gun and CCD camera of the coating device which employ | adopted this invention. It is the flowchart figure which showed the flow of the coating liquid filling control in the coating device which employ | adopted this invention. It is the flowchart figure which showed the flow of application | coating control in the coating device which employ | adopted this invention. It is the flowchart figure which showed the flow of the automatic application | coating control in the coating device which employ | adopted this invention. It is explanatory drawing which showed the structure of the drawing command in the coating device which employ | adopted this invention. It is the flowchart figure which showed the flow of the drawing control in the coating device which employ | adopted this invention. It is the flowchart figure which showed the flow of fixed line width control in the drawing control of FIG. It is the flowchart figure which showed the flow of constant density control in the drawing control of FIG.

Explanation of symbols

100 Servo Gun 101 Housing 102 Piston 103 Chamber 104 Packing Press 107, 107 Packing Press 108, 108 Blind Cover 109, 109 Needle Valve 110, 110 Shaft 111 Air Cylinder Tube 112 Air Cylinder Piston Head 113 Air Cylinder Head Cover 114 Servo Motor 115 Cup Ring 117 Ball screw 118 Ball guide 119 Bolt with hole 120 Packing set 121 Packing set 123 to 125 O-ring 126 Shaft 127 Air cylinder shaft 128 Spring 134 Obi 135 Fiber bracket 136 Sensor dog 138a, 138b Optical fiber 141 Discharge side valve unit 142 Filling side valve Unit 151a, 151b, 152a 152b Ports 152, 151 Air cylinder unit 161 Solenoid valve for discharge valve 162 Solenoid valve for filling valve 180 Dispenser chip 181 Application body 191 Pressure sensor head 192 Air operated regulator 193 Pressure sensor unit 200 Robot arm 300 Robot operation panel 301 I / O input Output board 302 Analog output board 400 PLC
401 power supply 402 PC (personal computer)
403 I / O input port 404 I / O output port 405 Analog input port 406 Positioning unit 407 Servo controller 501 Suction port 502 Mist separator 503, 504 Precision regulator 600 Stirrer 700 Sealed tank 701 Paint tube 800 CCD camera 801 Illumination 900 Control unit 901 Drawing program 903 Image processing unit 1001 Tool bracket 1002 Bracket 1003 Arm 1006 Shaft 1007 Gear cover 1008 Servo motor 1009, 1010 Spur gear 1012, 1013 Bearing holder set 1015 Proximity sensor 1016 Metal color

Claims (10)

A coating apparatus having contact coating means for applying a coating liquid to the coating object in contact with the coating object;
A robot arm that operates the coating apparatus to move the contact application means in contact with the object to be coated, and causes the coating apparatus to perform contact coating;
An imaging unit that is mounted on the robot arm together with the coating device, and that photographs the coating pattern of the coating solution formed on the coating object by the coating device;
Image processing means for analyzing image data photographed by the photographing means and generating information relating to a coating pattern forming state of the coating liquid;
Control means for feedback-controlling the application operation of the application apparatus or the operation of the robot arm based on information on the application pattern formation state of the application liquid generated by the image processing means;
Driving means for moving the photographing optical axis of the photographing means to different relative positions with respect to the coating device;
I have a,
The control means moves the photographing means via the driving means to a follow-up position for photographing the coating pattern of the coating liquid immediately after the formation on the object to be coated, according to the coating direction of the coating apparatus.
The image processing unit generates information on the actual values of the line width and density of the coating pattern of the coating liquid from the image data captured by the imaging unit, and the control unit is information on the actual values of the line width and the density. A feedback control of the line width and density of the coating pattern of the coating solution so that the value approaches the target value of the predetermined line width and density . In the feedback control related to the coating operation of the coating device or the operation of the robot arm by the control means, when the control amount for the coating device or the robot arm reaches a predetermined limit, the control means The automatic coating system according to claim 1 , wherein the feedback control is not performed. 3. The automatic coating system according to claim 2 , wherein when the control amount for the coating device or the robot arm reaches a predetermined limit, the control unit generates warning information for the user. . A supply amount for supplying the coating solution to the contact coating unit of the coating apparatus, and the control unit supplying the coating solution supplied from the coating solution supply unit does not sag from the contact coating unit; The automatic coating system according to any one of claims 1 to 3 , wherein the coating liquid supply means is controlled. The photographing means is supported so as to be able to turn to different arbitrary rotation positions centering on a straight line passing through the substantially center of the contact application means of the application apparatus, and the control means depends on the application direction of the application apparatus, 2. The imaging device according to claim 1 , wherein the imaging unit is moved to one of the rotation positions via the driving unit so as to image the coating pattern of the coating liquid immediately after formation on the coating object. Automatic application system. Operating a coating apparatus having a contact application means for applying a coating solution to the application object in contact with the application object, with a robot arm, and moving the contact application means in contact with the application object, Let the coating device perform contact coating,
Photographing the coating pattern of the coating liquid formed on the coated object by the coating device by photographing means mounted on the robot arm together with the coating device;
Analyzing the image data captured by the imaging means, performing image processing for generating information relating to the application pattern formation state of the application liquid, and applying the application operation of the application apparatus based on the information relating to the application pattern formation state of the application liquid, Or, feedback control of the operation of the robot arm ,
In the image processing, information on the actual values of the line width and the density of the coating pattern of the coating liquid is generated from the image data captured by the imaging unit, and the information on the actual values of the line width and the density is a predetermined line. Feedback control of the line width and concentration of the coating pattern of the coating solution so as to approach the target values of width and concentration,
The application pattern of the coating liquid immediately after formation on the object to be coated according to the coating direction of the coating device using a driving unit that moves the photographing optical axis of the photographing unit to a different relative position with respect to the coating device. A method for controlling an automatic coating system, characterized in that the photographing means is moved to a follow-up position for photographing . In the feedback control related to the coating operation of the coating device or the operation of the robot arm, when the control amount for the coating device or the robot arm reaches a predetermined limit, no further feedback control is performed. The method of controlling an automatic coating system according to claim 6 , wherein limiting is performed. 8. The method of controlling an automatic coating system according to claim 7 , wherein warning information is generated for a user when a control amount for the coating apparatus or the robot arm reaches a predetermined limit. A coating liquid supply unit configured to supply the coating liquid to the contact coating unit of the coating apparatus; and the coating liquid supplied from the coating liquid supply unit in a supply amount that does not sag from the contact coating unit. The method for controlling an automatic coating system according to any one of claims 6 to 8 , wherein the supply means is controlled. The photographing means is supported so as to be able to turn to different arbitrary rotational positions centering on a straight line passing through the substantially center of the contact application means of the application apparatus, and the object to be applied is dependent on the application direction of the application apparatus. The automatic coating system according to claim 6 , wherein the photographing unit is moved to one of the rotational positions via the driving unit so as to photograph the coating pattern of the coating liquid immediately after the formation. Control method.

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