JP6326598B2 - Fluid application system and fluid application method - Google Patents

Description

  The present invention relates to a fluid application system including a coating device that discharges fluid to a workpiece, and a moving unit that relatively moves the coating device and the workpiece. The present invention also relates to a fluid application method using an application device and a moving means. More specifically, in closed-loop application, the difference between the application amount of the joint portion (the portion where the start point and the end point are connected) and the application amount of the steady portion (the portion excluding the joint portion) can be eliminated, and the connection The present invention relates to a fluid application system and a fluid application method that can reduce entrainment of air in eyes.

Unless otherwise stated, the definitions of terms in this specification are as follows.
“Coating amount”: means a coating amount (g / mm) per unit length.

  Fluids such as adhesives, sealants, insulating agents, heat dissipation agents, and anti-seizure agents may be applied to parts (workpieces) in the manufacturing process of automobiles, electronic members, solar cells, and the like. A fluid application system can be used when applying fluid to the workpiece. The fluid application system can employ a configuration including an application device (for example, a dispenser) that discharges fluid to a workpiece and a moving unit (for example, an articulated robot) that relatively moves the application device and the workpiece.

  The coating apparatus includes a drive unit (for example, a motor), a fluid supply unit (for example, a pump or an actuator) whose discharge amount changes per unit time according to the output of the drive unit, and a fluid supplied from the fluid supply unit. A configuration including a nozzle for discharging the work can be employed. When applying a fluid to a workpiece using such an application device and a moving means, the application fluid on the end point side is overlapped and connected (connected) to the application fluid on the start point side to apply in a closed loop. There is a case.

  FIG. 1 is a top view schematically showing an example of a fluid (application fluid) applied in a closed loop shape. In the figure, a rectangular workpiece 51 and a coating fluid 52 applied along the outer periphery of the workpiece 51 are shown. In addition, the application start point S and the end point F are indicated by arrows, and the application direction is indicated by broken line arrows. In the closed loop application, as shown in the figure, a distance is provided between the application start point S and the application end point F. Thereby, the application fluid on the end point side is superimposed on the application fluid on the start point side, and the application fluid is connected.

  The closed loop application may be performed on the outer peripheral surface of the workpiece. FIG. 2 is a perspective view schematically showing an example of a fluid applied in a closed loop shape on the outer peripheral surface of a cylindrical workpiece. The figure shows a cylindrical workpiece 54 and a fluid 52 applied in an annular shape on the outer peripheral surface of the workpiece 54. Even when the closed loop coating is performed on the outer peripheral surface of the workpiece, the coating fluid is connected by superimposing the coating fluid on the end point side on the coating fluid on the start point side.

  In such a closed-loop application, the application amount of the joint portion may increase or air entrainment may occur. FIG. 3 is a side view showing a joint portion of a conventional coating fluid. In the same figure, the workpiece | work 51 and the application fluid 52 are shown, and an application | coating direction is shown with a broken-line arrow. As shown in the figure, a joint portion 52b is formed by overlapping an application fluid 52d at the end point with the application fluid 52c at the start point. As a result, the application amount of the joint portion 52b may be larger than the application amount of the steady portion 52a.

  In addition, when the fluid to be applied is a high-viscosity fluid, a fast-curing fluid, or a quick-drying fluid, air remains below the starting application fluid 52c. When this residual air is confined by the coating fluid 52d at the end point, air entrainment 53 occurs in the joint portion 52b as shown in FIG.

  Various proposals have heretofore been made regarding closed-loop application, for example, Patent Document 1. In Patent Document 1, it is proposed to detect the position of the start point (application start point) of the fluid applied to the workpiece and adjust the position of the end point (application end point) of the fluid so as to match the detected start point position. Has been. The detection of the start point position is performed by imaging the workpiece with a camera and detecting the distance formed by the start point position of the coating fluid with respect to the center of the visual field.

  In Patent Document 1, an air-type dispenser is used as a coating device that starts or stops discharging fluid by increasing or decreasing the pressure of a supplied gas. At the start of application, the nozzle of the application head starts moving, and simultaneously, a positive gas pressure is applied to the container of the application head, and discharge of the paste starts from the nozzle. As a result, the starting point is supposed to be tapered naturally.

  On the other hand, at the end of coating, the nozzle of the coating head stops moving, and at the same time, the application of the positive gas pressure to the container of the coating head is stopped and the negative gas pressure is applied. As a result, the discharge of the paste from the nozzle is stopped, and as a result, the end point is naturally tapered.

  In this way, when both the application start point and the application end point are tapered, by adjusting the application end point position as described above, if the start point and end point of the application fluid are appropriately overlapped, the result of the application fluid The width of the joint portion and the width of the steady portion (application amount) are assumed to be uniform.

  FIG. 4 is a schematic diagram showing an example of a control pattern in the coating method of Patent Document 1. FIG. 4A shows the relationship between the elapsed time and the moving speed, and FIG. 4B shows the elapsed time and the discharge per unit time. The relationship with quantity is shown. The control pattern shown in the figure is the control pattern for the closed-loop application shown in FIG. 1, and is the control pattern at the start of application and at the end of application in the application method of Patent Document 1 described above. In the figure, the timings of passing through the application start point S and end point F are indicated by arrows.

  Further, in the air-type dispenser used in Patent Document 1, when the fluid is sucked at the end of application, the amount of the fluid drawn into the nozzle is different every time, leading to variations in the starting point position. For this reason, it is considered effective to adjust the end point as proposed in Patent Document 1.

Patent No. 5180925

  As described above, when the fluid is applied in a closed loop using the application device and the moving unit, the amount of application at the joint portion may increase or air may be involved. Therefore, in the above-described Patent Document 1, it is proposed to detect the start point position of the application fluid and adjust the application end point position. In addition, if the taper that naturally occurs with the start of discharge and the taper that naturally occurs with the end of discharge are used, the width of the joint portion and the width of the steady portion of the applied fluid can be made uniform as a result. .

  However, as proposed in Patent Document 1, the start point position of the application fluid is detected and the end point position of the application is adjusted, that is, the distance between the start point of the application and the end point of the application is made constant. There is a limit to reducing the difference between the width of the fluid joint (application amount) and the width of the stationary part (application amount). This is because the relationship between the elapsed time at the start of application and at the end of application and the discharge amount is actually different from that shown in FIG.

  More specifically, the relationship between the elapsed time at the start of application and at the end of application and the discharge amount is influenced by the characteristics of the fluid (for example, viscosity) and the characteristics of the fluid supply means (pump), and the curve shape and gradient, The time required changes. Also, depending on the fluid and fluid supply means (pump), the relationship between the elapsed time at the start of application or at the end of application and the discharge amount changes each time application is performed, and the curve shape, gradient, and required time may vary. For this reason, there are various forms of the tapered shape at the start of application and at the end of application.

  FIG. 5 is a schematic diagram showing a first pattern example of an actual discharge amount in the coating method of Patent Document 1. FIG. 5A shows the relationship between the elapsed time and the discharge amount per unit time, and FIG. ) Indicates a joint portion of the applied fluid. The discharge amount pattern example shown in the figure shows the relationship between the actual elapsed time and the discharge amount and the shape of the joint portion of the applied fluid in the control pattern example shown in FIG. As shown in FIG. 6A, the time required to reach a desired discharge amount at the start of application may differ from the time required to end discharge at the end of application. In this case, even if the start point position of the application fluid is detected and the end point position of the application is adjusted, the application amount of the joint portion is smaller than the application amount of the steady portion as shown in FIG.

  FIG. 6 is a schematic diagram showing a second pattern example of the actual discharge amount in the coating method of Patent Document 1. FIG. 6A shows the relationship between the elapsed time and the discharge amount per unit time, and FIG. ) Indicates a joint portion of the applied fluid. The discharge amount pattern example shown in the figure shows the relationship between the actual elapsed time and the discharge amount and the shape of the joint portion of the applied fluid in the control pattern example shown in FIG. As shown in FIG. 5A, both the time required to reach a desired discharge amount at the start of application and the time required to end discharge at the end of application may be long. In this case, even if the start point position of the application fluid is detected and the end point position of the application is adjusted, the overlapping length becomes shorter with respect to the taper length, and as shown in FIG. The amount is less than the coating amount of the stationary part.

  Therefore, it is desired to further reduce the difference between the application amount of the joint portion and the application amount of the steady portion. When strict accuracy is required, the coating method proposed in Patent Document 1 is particularly insufficient. Here, the case where strict accuracy is required corresponds to, for example, a case where a sealing agent is applied by a FIPG (Formed In Place Gasket) method or a CIPG (Cured In Place Gasket) method in manufacturing an automobile engine. .

  In addition, when the fluid to be applied is a high-viscosity fluid, a fast-curing fluid, or a quick-drying fluid, air remains below the starting application fluid 52c. When this residual air is confined by the coating fluid 52d at the end point, air entrainment 53 occurs in the joint portion 52b as shown in FIG.

  Furthermore, in the method proposed in Patent Document 1, it is necessary to capture an image with a camera, analyze the image to detect the start point, and calculate the distance. For this reason, a camera and an image analysis apparatus are indispensable, the apparatus configuration becomes complicated, and the equipment cost increases.

  The present invention has been made in view of such a situation, and in closed-loop application, the difference between the application amount of the joint portion and the application amount of the steady portion can be eliminated, and air entrainment of the joint portion is involved. It is an object of the present invention to provide a fluid application system and a fluid application method capable of reducing the above.

  In order to solve the above problems, the present inventors conducted various tests, and as a result of intensive studies, in the closed-loop application, by operating the number of rotations of the motor in the application start process, the application amount is reduced. It was conceived to increase gradually intentionally. In order to cope with the gradual increase in the coating amount in the coating start process, it was conceived that the coating amount was intentionally decreased by manipulating the rotational speed of the motor in the coating end process. Thereby, while being able to eliminate the difference between the application amount of the joint portion and the application amount of the steady portion, it is possible to reduce the entrainment of air at the joint portion.

  The present invention has been completed on the basis of the above-described findings, and has the gist of the fluid application system (1) to (6) below and the fluid application method (7) below.

(1) A fluid application system comprising: a coating device that discharges fluid to a workpiece; a moving unit that relatively moves the coating device and the workpiece; and a control unit that controls the coating device and the moving unit. The coating apparatus includes a driving unit and a fluid supply unit that changes a discharge amount per unit time in accordance with an output of the driving unit. A fluid application system, which is a control unit that gradually increases the application amount per unit length and gradually decreases the application amount per unit length in the process of application completion.

(2) In the fluid application system according to (1), the control unit gradually increases the application amount in an application start process and gradually decreases the application amount in an application end process. In a fluid applied to a workpiece, a fluid application system in which an application amount per unit length of a joint portion is made equal to an application amount per unit length of a stationary portion.

(3) In the fluid application system according to (1) or (2), when the control unit gradually increases the application amount, the output of the driving unit is adjusted to vary the discharge amount. The fluid application system gradually increases the application amount by reducing the application amount and gradually decreases the application amount by adjusting the output of the driving means and changing the discharge amount when the application amount is gradually decreased. .

(4) In the fluid application system according to (1) or (2), when the control unit gradually increases the application amount, the control unit controls the moving unit to control the application device and the workpiece. The application amount is gradually increased by changing the relative movement speed of the ink, and the application amount is gradually changed by controlling the moving means to change the movement speed when the application amount is gradually reduced. Reduce fluid application system.

(5) In the fluid application system according to any one of (1) to (4), when the control unit gradually increases the application amount, the application amount is increased to a substantially linear shape, A fluid application system that reduces the application amount to a substantially linear shape when gradually reducing the application amount.

(6) The fluid application system according to any one of (1) to (5), wherein the fluid supply unit has a rotation volume in which a discharge amount per unit time varies depending on a rotation speed of the drive unit. A fluid application system, which is a pump of the type.

(7) The fluid application system according to (6), wherein the rotary displacement pump is a uniaxial eccentric screw pump.

(8) A method of applying a fluid to the workpiece in a closed loop using a fluid application system that includes a coating device that discharges fluid to the workpiece, and a moving unit that relatively moves the coating device and the workpiece. The coating apparatus includes a driving unit and a fluid supply unit that changes a discharge amount per unit time according to an output of the driving unit, and gradually increases the coating amount per unit length in a coating start process. In addition, a fluid application method that gradually reduces the application amount per unit length in the application completion process.

  In the present invention, “increasing the coating amount to a substantially linear shape” is not limited to the case where the coating amount is increased to a linear shape, but the viscosity of the fluid applied when the coating amount is increased to a linear shape, or fluid supply means It means that it is allowed to include fluctuations (noise) due to characteristics (for example, response delay) of (pump). Further, as will be described later, it may be allowed to increase partially in a curved line, and partially increasing in a curved line means, for example, increasing in a curved line at the start or end of a coating start process (gradual increase). Is applicable.

  On the other hand, “reducing the application amount to a substantially linear shape” is not limited to the case where the application amount is reduced to a linear shape, but the viscosity of the fluid applied when the application amount is reduced to a linear shape, or fluid supply means ( It means that it is allowed to include fluctuations (noise) due to the characteristics of the pump). Also, as will be described later, it may be allowed to decrease partially in a curved line, and partially decreasing in a curved line means, for example, when decreasing in a curved line at the start or end of the coating end process (gradual decrease) Is applicable.

  The fluid application system and the fluid application method of the present invention gradually increase the application amount in the application start process and gradually decrease the application amount in the application end process in the closed-loop application. Thereby, the connection part in which the application quantity is reducing from the stationary part can be formed in the application fluid at the start point and the application fluid at the end point, respectively. For this reason, the connection portion of the application fluid at the start point and the connection portion of the application fluid at the end point overlap each other at the joint portion, and the difference between the application amount of the joint portion and the application amount of the steady portion can be eliminated. In addition, since the amount of air remaining below the coating fluid at the starting point is reduced, the entrainment of air at the joint portion can be reduced.

It is a top view which shows typically an example of the fluid apply | coated in the closed loop shape. It is a perspective view which shows typically an example of the fluid apply | coated to the outer peripheral surface of a cylindrical workpiece | work in the closed loop shape. It is a side view which shows the joint part of the conventional coating fluid. It is a schematic diagram which shows the example of a control pattern in the application | coating method of patent document 1, The figure (a) is the relationship between elapsed time and a moving speed, The figure (b) is the relationship between elapsed time and the discharge amount per unit time. Indicates. It is a schematic diagram which shows the 1st pattern example of the actual discharge amount in the application | coating method of patent document 1, The figure (a) is the relationship between elapsed time and the discharge amount per unit time, The figure (b) is application fluid. The joint part of is shown. It is a schematic diagram which shows the 2nd pattern example of the actual discharge amount in the application | coating method of patent document 1, The figure (a) is the relationship between elapsed time and the discharge amount per unit time, The figure (b) is application fluid. The joint part of is shown. It is a schematic diagram which shows the structural example of the fluid application | coating system of this invention. It is a side view which shows the joint part of the application fluid at the time of applying the control of the application quantity by this invention, The figure (a) shows the case where the application quantity is increased / decreased stepwise, The figure (b) is a rough line. The case where the application amount is increased or decreased in the shape is shown. It is a schematic diagram which shows the example of a control pattern in the case of increasing / decreasing a coating amount with the rotation speed of a motor, The figure (a) is the relationship between elapsed time and a moving speed, The figure (b) is elapsed time and the rotation speed of a motor. (C) shows the relationship between the elapsed time and the discharge amount per unit time. It is a schematic diagram which shows the example of a control pattern in the case of increasing / decreasing a coating amount with a moving speed, The same figure (a) is the relationship between elapsed time and a moving speed, The same figure (b) is the elapsed time and the rotation speed of a motor. FIG. 3C shows the relationship between the elapsed time and the discharge amount per unit time. It is a schematic diagram which shows the example of a control pattern which increases / decreases coating amount at the time of completion | finish of an application | coating start process, and the application | coating end process, The figure (a) is the relationship between elapsed time and the rotation speed of a motor, the figure (B) shows the relationship between the elapsed time and the discharge amount per unit time, and FIG. 5 (c) shows the joint portion of the applied fluid. It is a schematic diagram which shows the example of a control pattern which increases / decreases in the shape of a curve at the time of completion | finish of an application | coating start process, and the completion | finish process of an application | coating, The figure (a) is the relationship between elapsed time and the rotation speed of a motor, The figure (b). Is the relationship between the elapsed time and the discharge amount per unit time, and FIG. 5C shows the joint portion of the applied fluid. It is a schematic diagram which shows the example of a control pattern which changed the inclination at the time of increasing / decreasing application amount to a rough line shape, The figure (a) is the relationship between elapsed time and the rotation speed of a motor, The figure (b) is elapsed time. (C) shows the joint portion of the applied fluid. It is sectional drawing which shows typically the example of a structure of the uniaxial eccentric screw pump suitable as a rotary displacement type pump.

  Hereinafter, a fluid application system and a fluid application method of the present invention will be described with reference to the drawings.

[Configuration example of fluid application system of the present invention]
FIG. 7 is a schematic diagram showing a configuration example of the fluid application system of the present invention. The fluid application system 10 shown in the figure includes an application device 20 that discharges fluid to a workpiece, a moving unit 30 that relatively moves the application device 20 and the workpiece (not shown), and the application device 20 and the movement unit 30. And control means 11 for controlling.

  The coating apparatus 20 includes a motor 22 that is a driving unit, a pump 21 that is a fluid supply unit, and a nozzle 23 that is attached to the tip of the pump. The discharge amount per unit time of the pump 21 changes according to the output (rotation speed) of the motor 22. The fluid discharged from the pump 21 is applied to the workpiece via the nozzle 23. The motor 22 is connected to the control means 11 via a cable in order to receive a command of its rotational speed and direction (forward or reverse) and to transmit the actual rotational speed.

  The pump 21 of the coating device 20 is connected to a fluid pumping device 24 via a pipe 25. The fluid pumping device 24 pumps a fluid (not shown) stored in a container 26 such as a drum, and distributes the piping 25 (for example, a flexible hose) to supply it to the pump 21.

  In the fluid application system 10 shown in the figure, the moving means 30 is constituted by an articulated robot, and the operation of the articulated robot 30 is controlled by the control means 11. A coating device 20 is attached to the tip of the arm of the articulated robot 30. The fluid application system 10 shown in the figure fixes a work (not shown) while moving the pump 21 by the articulated robot 30 to realize relative movement between the application device 20 and the work. The control means 11 is also connected to the articulated robot 30 with a cable, and transmits a signal to the articulated robot 30 and also transmits the movement speed, position information, etc. of the articulated robot 30 to the control means 11.

  The control means 11 provided in the fluid application system of the present invention gradually increases the application amount in the application start process and gradually decreases the application amount in the application end process in the closed-loop application. The fluid application method of the present invention gradually increases the application amount in the application start process and gradually decreases the application amount in the application end process.

  Below, the control of the coating amount realized by the control means 11 provided in the fluid coating system of the present invention and the control of the coating amount performed by the fluid coating method of the present invention will be described in detail. Hereinafter, the control of the coating amount is collectively referred to as the coating amount control according to the present invention.

  The application amount control according to the present invention targets the application start process and the application end process in closed-loop application, in other words, the joint part. For this reason, what is necessary is just to control a coating amount by a conventional method for a stationary part.

  FIG. 8 is a side view showing the joint portion of the application fluid when the application amount control according to the present invention is applied. FIG. 8A shows a case where the application amount is increased or decreased stepwise. ) Shows a case where the coating amount is increased or decreased in a substantially linear shape. In the same figure, the workpiece | work 51 and the application fluid 52 are shown, and an application | coating direction is shown with a broken-line arrow.

The control of the coating amount according to the present invention gradually increases the coating amount in the coating start process. The gradual increase in the coating amount can be realized, for example, by manipulating the motor rotation speed (min ⁻¹ ) or manipulating the moving speed (mm / s). Thereby, the connection part 52e is formed in the application fluid 52c at the starting point, and the connection part 52e gradually decreases in thickness or gradually decreases in width as it approaches the tip.

Also, the control of the coating amount according to the present invention gradually decreases the coating amount in the process of finishing the coating. This gradual decrease in the coating amount can be realized, for example, by manipulating the motor rotation speed (min ⁻¹ ) or manipulating the moving speed (mm / s). As a result, a connecting portion 52f is formed in the end-point application fluid 52d, and the connecting portion 52f gradually decreases in thickness or gradually decreases in width as it approaches the tip.

  As described above, the control of the coating amount according to the present invention intentionally changes the thickness and width of the coating fluid 52c at the start point and the coating fluid 52d at the end point, so that the coating amount gradually decreases as it approaches the tip. In this case, in the joint portion 52b, the connection portion 52e of the starting application fluid whose application amount is reduced by a desired amount from the steady portion 52a and the end point of the application fluid whose application amount is reduced by a desired amount from the steady portion 52a. It will be in the state where the connection part 52f overlaps. Thereby, it can prevent that the application quantity of the joint part 52b becomes larger than the application quantity of the stationary part 52a, or decreases. For this reason, the application amount control according to the present invention can eliminate the difference between the application amount of the joint portion 52b and the application amount of the stationary portion 52a.

  As described above, the air entrainment occurs when the air remaining below the starting-point application fluid is trapped by the end-point application fluid. In the application amount control according to the present invention, the application amount gradually decreases as it approaches the tip, so the amount of air remaining below the starting application fluid 52c decreases. For this reason, the entrainment 53 of the air of the joint part 52b can be reduced.

  There is no particular limitation on the gradual increase in the coating amount in the coating start process and the gradual decrease in the coating amount in the coating end process, and various patterns can be adopted. For example, as shown in FIG. 8A, it is possible to adopt a pattern that increases or decreases in a staircase pattern. In this case, the number of steps and the height difference per step are not limited, and may be appropriately set according to, for example, the thickness and width of the coating fluid and the required accuracy.

  As shown in FIG. 8B, the control of the coating amount according to the present invention increases the coating amount in a substantially linear shape and gradually decreases the coating amount as shown in FIG. 8 (b). As shown in FIG. 8B, it is preferable to reduce the coating amount to a substantially linear shape. Thereby, the effect which can eliminate the difference of the application quantity of the joint part 52b and the application quantity of the stationary part 52a becomes remarkable, and the application quantity can be made uniform by the joint part 52b and the stationary part 52a. Further, the amount of air existing below the starting application fluid 52c is further reduced, and the entrainment of air at the joint portion 52b can be greatly reduced.

  As described above, the gradual increase of the coating amount in the coating start process and the gradual decrease of the coating amount in the coating end process are performed by operating the motor rotation speed (output of the driving means) or the moving speed as described above. realizable. It can also be realized by combining the operation of the motor speed (output of the driving means) and the operation of the moving speed. Hereinafter, an embodiment for manipulating the rotational speed of the motor and an embodiment for manipulating the moving speed will be described with reference to the drawings.

  In the control of the coating amount according to the present invention, as in the conventional coating method, the distance (from the start point S to the end point F is set so that the connection portion of the application fluid at the start point and the connection portion of the application fluid at the end point overlap at the joint portion. For example, a distance of about 10 mm) is provided (see FIG. 1).

  FIG. 9 is a schematic diagram showing an example of a control pattern in the case where the coating amount is increased / decreased depending on the number of rotations of the motor. FIG. 9 (a) shows the relationship between the elapsed time and the moving speed, and FIG. FIG. 5C shows the relationship between the number of revolutions of the motor and the relationship between the elapsed time and the discharge amount per unit time. The control pattern in the figure is a control pattern in the case where the coating amount is increased or decreased in a substantially linear shape as shown in FIG. 8B. Moreover, in the same figure, the timing at which the coating apparatus passes the start point S and the end point F of FIG. 1 is indicated by arrows.

  When the coating amount is gradually increased in the coating start process, the number of revolutions of the motor is increased (adjusting the output of the driving means) as shown in FIG. Fluctuate to increase. At that time, the moving means is controlled so that the moving speed is constant, as shown in FIG. Thereby, the application amount to the workpiece is gradually increased to a substantially linear shape.

  When the coating amount is gradually reduced in the coating end process, the motor rotation speed is decreased (adjusting the output of the driving means) as shown in FIG. Fluctuate to decrease. At that time, the moving means is controlled so that the moving speed is constant, as shown in FIG. Thereby, the application amount to the workpiece is gradually reduced to a substantially linear shape.

  FIG. 10 is a schematic diagram showing an example of a control pattern when the coating amount is increased / decreased depending on the moving speed. FIG. 10 (a) shows the relationship between the elapsed time and the moving speed, and FIG. 10 (b) shows the elapsed time and the motor. FIG. 5C shows the relationship between the rotational speed and the relationship between the elapsed time and the discharge amount per unit time. The control pattern in the figure is a control pattern in the case where the coating amount is increased or decreased in a substantially linear shape as shown in FIG. 8B. Moreover, in the same figure, the timing at which the coating apparatus passes the start point S and the end point F of FIG. 1 is indicated by arrows.

  When the coating amount is gradually increased in the coating start process, the moving means is controlled to gradually decrease the relative moving speed between the coating apparatus and the workpiece into a substantially linear shape as shown in FIG. At that time, as shown in FIG. 5B, the motor is started to start application with the discharge amount of the coating apparatus being constant. Thereby, the application amount to the workpiece is gradually increased to a substantially linear shape.

  When the coating amount is gradually decreased in the process of finishing the coating, the moving means is controlled as shown in FIG. 4A to gradually increase the relative moving speed between the coating apparatus and the workpiece into a substantially linear shape. At that time, as shown in FIG. 5B, the motor is stopped, and the discharge is finished while the discharge amount of the coating apparatus is kept constant. Thereby, the application amount to the workpiece is gradually reduced to a substantially linear shape.

  Note that when the motor is started in the application start process and fluid is discharged from the coating apparatus at a predetermined discharge amount, it takes time for the discharge amount of the coating apparatus to respond to the start of the motor. In order to suppress this response delay, in the control pattern shown in the figure, the rotation speed of the motor is increased beyond the rotation speed corresponding to the predetermined discharge amount, and then the rotation speed corresponding to the predetermined discharge amount is set.

  Further, when the motor is stopped in the process of finishing the application to finish the discharge of the coating apparatus, it takes time for the discharge amount of the coating apparatus to respond to the stop of the motor. In order to suppress this response delay, in the control pattern example shown in the figure, the motor is stopped after the motor is reversed.

  In the control pattern examples shown in FIGS. 9 and 10, both are increased in a linear shape from the start to the end of the coating start process (gradual increase in coating amount). For example, various conditions such as the thickness and width of the coating fluid, and the required accuracy Depending on the above, it may be partially increased in a curved shape. In addition, although it is decreased in a linear shape from the start to the end of the coating end process (gradual decrease in coating amount), it may be partially reduced in a curved shape according to the above conditions. Furthermore, the inclination at the time of increasing / decreasing the coating amount to a substantially linear shape can be changed according to the above conditions. Specific examples thereof will be described with reference to the drawings.

  FIG. 11 is a schematic diagram showing an example of a control pattern for increasing and decreasing the coating amount at the end of the application start process and at the start of the application end process. FIG. 11 (a) shows the elapsed time and the number of rotations of the motor. (B) shows the relationship between the elapsed time and the discharge amount per unit time, and (c) shows the joint portion of the applied fluid. The control pattern example shown in the figure is a control pattern example in the case where the coating amount is increased or decreased according to the number of rotations of the motor shown in FIG. It is intended to fluctuate. Since the relationship between the moving speed and the elapsed time is the same as the relationship shown in FIG. 9A, the illustration is omitted. Moreover, the workpiece | work 51 and the application fluid 52 are shown in the figure (c).

  Specifically, at the end of the application start process, the discharge rate is changed in an arc shape so that the rate of change (absolute value of inclination) gradually decreases. As a result, the coating amount is changed in an arc shape by gradually reducing the change rate. On the other hand, at the start of the application end process, the discharge rate is changed in an arc shape so that the rate of change (absolute value of inclination) gradually increases. As a result, the coating amount is changed in an arc shape by gradually increasing the change rate. In such a control pattern example, a joint portion 52b of the application fluid as shown in FIG.

  FIG. 12 is a schematic diagram showing an example of a control pattern that is increased or decreased in a curved line at the end of the application start process and at the end of the application end process. FIG. 12 (a) shows the relationship between the elapsed time and the rotation speed of the motor. FIG. 2B shows the relationship between the elapsed time and the discharge amount per unit time, and FIG. 2C shows the joint portion of the applied fluid. The control pattern example shown in the figure is a control pattern example in the case where the coating amount is increased or decreased according to the number of rotations of the motor shown in FIG. 9. In the control pattern example shown in FIG. It is intended to fluctuate. Since the relationship between the moving speed and the elapsed time is the same as the relationship shown in FIG. 9A, the illustration is omitted. Moreover, the workpiece | work 51 and the application fluid 52 are shown in the figure (c).

  Specifically, at the end of the application start process, the discharge rate is changed in an arc shape so that the rate of change (absolute value of inclination) gradually decreases. As a result, the coating amount is changed in an arc shape by gradually reducing the change rate. On the other hand, at the end of the application end process, the discharge rate is changed in an arc shape so that the rate of change (absolute value of inclination) gradually decreases. As a result, the coating amount is changed in an arc shape by gradually reducing the change rate. In such a control pattern example, a joint portion 52b of the application fluid as shown in FIG.

  FIG. 13 is a schematic diagram showing an example of a control pattern in which the inclination when increasing / decreasing the coating amount in a substantially linear shape is changed. FIG. 13 (a) shows the relationship between the elapsed time and the rotational speed of the motor, and FIG. ) Shows the relationship between the elapsed time and the discharge amount per unit time, and FIG. 5C shows the joint portion of the applied fluid. The control pattern example shown in the figure is substantially the same as the control pattern in the case where the coating amount is increased or decreased according to the number of rotations of the motor shown in FIG. 9, and the inclination and the coating amount when the coating amount is gradually increased to a substantially linear shape. The inclination when gradually reducing the shape is changed. Since the relationship between the moving speed and the elapsed time is the same as the relationship shown in FIG. 9A, the illustration is omitted. Moreover, the workpiece | work 51 and the application fluid 52 are shown in the figure (c).

  Specifically, as compared with the control pattern shown in FIG. 9, the gradient when the coating amount is gradually increased to a substantially linear shape is increased, and the variation rate of the discharge amount is increased. On the other hand, the absolute value of the gradient when gradually reducing the coating amount to a substantially linear shape was increased, and the absolute value of the variation rate of the discharge amount was increased. In such a control pattern example, as shown in FIG. 3C, the angle θ of the inclined surface of the connecting portion 52e becomes large in the starting application fluid 52c.

  In the fluid application system shown in FIG. 7, a pump whose discharge amount per unit time changes according to the number of rotations of the motor is used as the fluid supply means. As the pump, a rotary displacement pump can be adopted, and the rotary displacement pump is, for example, a uniaxial eccentric screw pump, a gear pump, or a rotary pump.

  In the fluid application system and the fluid application method of the present invention, the fluid supply means is not limited to the rotary displacement pump described above. For example, a solenoid pump having a mover that is displaced by the excitation action of a solenoid can be employed. In this solenoid pump, the discharge amount changes according to the operation cycle of the solenoid serving as the driving means. In addition, a fluid supply unit that supplies a fluid according to the pressure of the supplied gas can be employed. In this case, the discharge amount of the fluid supply unit changes according to an increase or decrease in the pressure of the gas supplied by the driving unit.

  In the fluid application system and the fluid application method of the present invention, it is preferable that the fluid supply means is a rotary positive displacement pump in which the discharge amount per unit time varies depending on the rotation speed of the drive means. In the case of a rotary displacement pump, the discharge amount can be changed with high accuracy in accordance with the rotational speed of the driving means. For this reason, the difference of the application amount of a joint part and the application amount of a stationary part can be eliminated more easily.

  In the fluid application system and the fluid application method of the present invention, the rotary displacement pump is preferably a uniaxial eccentric screw pump.

  FIG. 14 is a cross-sectional view schematically showing a configuration example of a uniaxial eccentric screw pump suitable as a rotary displacement pump. The uniaxial eccentric screw pump 40 shown in the figure includes a male screw type rotor 42 that rotates eccentrically upon receiving power, and a stator 43 whose inner peripheral surface is formed into a female screw type. Such a rotor 42 and a stator 43 are accommodated in the casing 41. The casing 41 is a metallic cylindrical member, and a first opening 41a is provided on one end side in the longitudinal direction. The first opening 41a functions as a discharge port of the uniaxial eccentric screw pump 40, and a nozzle that discharges fluid to the workpiece is attached to the discharge port.

  A second opening 41 b is provided on the outer periphery of the casing 41. The second opening 41 b communicates with the internal space of the casing 41 at the middle portion of the casing 41 in the longitudinal direction. Such a 2nd opening part 41b functions as a suction inlet of the uniaxial eccentric screw pump 40, and is connected with the above-mentioned fluid pumping apparatus via piping.

  The stator 43 is made of an elastic body such as rubber or a resin. The inner hole 43a of the stator 43 has a single-stage or multi-stage female thread shape with n strips. On the other hand, the rotor 42 is a metal shaft, and has a single-stage or multi-stage female screw shape with n-1 strips.

  In the uniaxial eccentric screw pump 40 shown in the figure, the stator 43 has a multi-stage female thread shape with two ridges, and the cross section of the inner hole of the stator 43 is substantially oval at any position in the longitudinal direction. On the other hand, the rotor 42 has a male screw shape that is eccentric with a single thread, and the cross section of the rotor 42 is substantially perfectly circular at any position in the longitudinal direction. The rotor 42 is inserted into an inner hole 43a formed in the stator 43, and can be freely eccentrically rotated inside the inner hole 43a.

  In order to make the rotor 42 eccentrically rotatable, the rotor 42 is connected to a rod 45 via a first universal joint 44, and the rod 45 is connected to a drive shaft 47 via a second universal joint 46. Although a detailed description is omitted, the drive shaft 47 is rotatably held by the casing 41 in a state where a gap with the casing 41 is sealed. Such a drive shaft 47 is connected to the main shaft 22 a of the motor 22. For this reason, as the main shaft 22a rotates by the operation of the motor 22, the drive shaft 47 rotates, and the rotor 42 connected via the universal joint or the rod rotates eccentrically.

  When the rotor 42 is rotated in the inner hole 43 a of the stator 43, the space partitioned by the rotor 42 and the stator inner hole 43 a advances in the longitudinal direction of the stator 43 while rotating in the stator 43. For this reason, when the rotor 42 is rotated, the fluid can be sucked from one end side of the stator 43, and the sucked fluid can be transferred toward the other end side of the stator 43 and discharged. The uniaxial eccentric screw pump 40 shown in the figure can pump the fluid sucked from the second opening 41b and discharge it from the first opening 41a by rotating the rotor 42 in the forward direction.

  Such a uniaxial eccentric screw pump can change the discharge amount freely and accurately by controlling the rotation of its driving means (motor). For this reason, if the fluid supply means is a uniaxial eccentric screw pump, the difference between the application amount of the joint portion and the application amount of the steady portion can be more easily eliminated. Further, in the uniaxial eccentric screw pump, if the rotation control pattern of the driving means (motor) is the same, the pattern of the same discharge amount is reproduced. This also makes it easier to eliminate the difference between the application amount at the joint and the application amount at the stationary part.

  In addition, if a single-shaft eccentric screw pump is used, the reproducibility is high, so that the same amount of liquid can be drawn into the nozzle every time the fluid is sucked at the end of discharge. For this reason, the tip position of the fluid remaining in the nozzle can be made constant, the response time at the start of discharge becomes uniform, and the response is excellent. Therefore, since there is no variation in the starting point position in the coating start process, it is not necessary to detect the starting point position of the coating fluid and adjust the coating end point position. As a result, a camera that captures the start point and an analysis device that analyzes the image are not required, and it is possible to prevent complication of the apparatus configuration and increase in equipment cost.

  In the fluid coating system of the present invention, the moving means for relatively moving the coating device and the workpiece is not limited to the articulated robot 30 that moves the coating device 20 as shown in FIG. The moving means includes, for example, a Z-axis direction transport device that feeds and moves the coating apparatus in the Z-axis direction, a Y-axis direction transport device that feeds and moves the Z-axis direction transport device in the Y-axis direction, and the Y-axis direction transport device Can be configured with an X-axis direction transport device that feeds and moves the X-axis in the X-axis direction.

  Further, the moving means includes a chuck that holds the workpiece rotatably around the Z axis, a Z axis direction conveying device that feeds and moves the coating device in the Z axis direction, and moves the Z axis direction conveying device in the X axis direction. And an X-axis direction transport device.

  In the configuration example of the fluid application system shown in FIG. 7, the moving unit 30 is controlled together with the coating apparatus 20 by one control unit 11, but the fluid application system of the present invention is not limited to this configuration example. For example, it can be constituted by a plurality of control means, and more specifically can be constituted by a first control means for controlling the coating apparatus and a second control means for controlling the moving means.

  As described above, the fluid application system and the fluid application method of the present invention can eliminate the difference between the application amount of the joint portion and the application amount of the steady portion in the closed-loop application, and can also entrain the air in the joint portion. Can be reduced. Such a fluid application system and fluid application method of the present invention apply fluids such as adhesives, sealants, insulating agents, heat dissipation agents, and anti-seizure agents to parts in the manufacturing process of automobiles, electronic members, solar cells and the like. You can use it effectively.

10: Fluid application system 11: Control means 20: Application device
21: Pump (fluid supply means), 22: Motor (drive means),
22a: main shaft of motor, 23: nozzle, 24: fluid pumping device,
25: piping, 26: container, 30: moving means (articulated robot),
40: Uniaxial eccentric screw pump (fluid supply means), 41: Casing,
41a: 1st opening part, 41b: 2nd opening part, 42: Rotor, 43: Stator,
43a: inner hole, 44: first universal joint, 45: rod, 46: second universal joint,
47: drive shaft, 51: rectangular workpiece, 52: coating fluid,
52a: stationary part, 52b: joint part, 52c: coating fluid at the starting point,
52d: end point application fluid, 52e: start point application fluid connection,
52f: Application fluid connecting portion at the end point 53: Air entrainment 54: Cylindrical workpiece

Claims (6)

A coating device that discharges fluid to the workpiece; a moving unit that relatively moves the coating device and the workpiece; and a control unit that controls the coating device and the moving unit , wherein the fluid is closed to the workpiece. A fluid application system for applying in a shape ,
The coating apparatus includes a driving unit and a fluid supply unit that changes a discharge amount per unit time according to an output of the driving unit,
Said control means, along with gradually increasing the coating amount per unit length in a coating cloth initiation process, Ri gradually controller der to decrease the coating amount per unit length in the coating end process,
When the control unit gradually increases the coating amount, the control unit gradually increases the coating amount by adjusting the output of the driving unit to change the discharge amount, and gradually decreases the coating amount. A fluid application system that gradually decreases the application amount by adjusting the output of the driving means to vary the discharge amount . The fluid application system of claim 1,
The control means gradually increases the coating amount in the coating start process and gradually decreases the coating amount in the coating end process, so that the fluid per unit length of the joint portion is applied to the fluid applied to the workpiece. A fluid application system in which the application amount is equivalent to the application amount per unit length of the stationary part. The fluid application system according to claim 1 or 2,
When the control unit gradually increases the coating amount, the control unit gradually increases the coating amount by controlling the moving unit to change a relative moving speed between the coating apparatus and the workpiece, and A fluid application system that gradually reduces the coating amount by controlling the moving means to vary the moving speed when the coating amount is gradually decreased. The fluid application system according to any one of claims 1 to 3 ,
A fluid application system in which the control means increases the application amount in a substantially linear shape when gradually increasing the application amount, and decreases the application amount in a substantially linear shape when gradually decreasing the application amount. . The fluid application system according to any one of claims 1 to 4 ,
The fluid application system, wherein the fluid supply unit is a rotary displacement pump in which a discharge amount per unit time changes according to the number of rotations of the drive unit. The fluid application system according to claim 5 ,
The fluid application system, wherein the rotary displacement pump is a uniaxial eccentric screw pump.

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