JPH07124509A - Method and apparatus for applying viscous fluid - Google Patents

Abstract

PURPOSE:To prevent bubbles from generating between viscous fluid and the bottom face of an article on which the fluid is applied when the fluid is applied along the surface of the article with a discharge nozzle brought close to the article. CONSTITUTION:A detector 24 which detects viscous fluid in advance is installed in front of an advancing discharge nozzle 22 which is attached at the end of a fluid discharge apparatus 18, while a detector 26 which detects an application condition is installed behind the nozzle 22. The height and width of fluid 30 in front of a discharge opening 29 is detected by the detector 24 during the application, while the height and width of a surface on which the fluid is applied behind the discharge nozzle 22 is detected by the detector 26. The amount of the fluid in front of the discharge opening 29 and the amount of the fluid behind the nozzle 22 are calculated based on these data, and the moving speed of the discharge nozzle 22 and the discharge speed of the fluid 30 are controlled based on the data of the fluid amount to conduct application without bubble generation.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a sealant, an adhesive,
The present invention relates to a method and an apparatus for applying a viscous fluid such as liquid rubber or a gasket, and more particularly to improving coating quality.

[0002]

2. Description of the Related Art As a method for applying a viscous fluid, a method for applying a viscous fluid while the ejection port of an ejection nozzle for ejecting the viscous fluid is brought close to the surface of an object to be coated and relatively advanced along the surface. It has been known. Since a coating defect may occur when a viscous fluid is coated by this coating method, a coating apparatus having a function of repairing the coating defect has been developed, one example of which is Japanese Patent Laid-Open No. 1-159075.
It is described in Japanese Patent Publication No. The coating device described in the above publication,
A coating defect is detected in the coating process, and the detected defect is later repaired to obtain a good coating state.

[0003]

However, in the coating device described in the above publication, the portion not coated with the viscous fluid or the portion lacking the amount of the viscous fluid can be repaired satisfactorily. It is difficult to remove air bubbles trapped between the fluid and the surface to be coated. For example, as shown in FIGS. 16 and 17, when the viscous fluid 82 is poured into the groove 80, the viscous fluid 82 discharged from the discharge port 85 and the groove bottom surface 86 are moved while the discharge nozzle 84 moves. Bubbles 88 may occur in the inside. If the discharge speed, which is the discharge amount of the viscous fluid per unit time, is too small or the discharge nozzle moving speed is too high, the discharge nozzle 84
A gap is formed between the viscous fluid 82 immediately below and the groove bottom surface 86. If the discharge speed increases or the moving speed decreases before the gap is filled with the viscous fluid 82, the gap is in the front in the discharge nozzle advancing direction (hereinafter, simply referred to as the front, and the rear in the discharge nozzle advancing direction is simply referred to as the rear). .) Is closed to form a bubble 88. It is difficult to remove the air bubbles 88 formed in this way, and it is particularly difficult with a highly viscous fluid. If the viscous fluid is opaque, bubbles 88
Even the discovery of is difficult. Therefore, it is an object of the present invention to obtain a viscous fluid application method and an application device capable of avoiding generation of bubbles in order to solve the above problems.

[0004]

In order to solve the above-mentioned problems, a first aspect of the present invention is to make a discharge port of a discharge nozzle for discharging a viscous fluid close to the surface of an object to be coated, and to relatively move along the surface. In the method of applying viscous fluid while advancing,
The gist of the present invention is to apply a part of the viscous fluid discharged from the discharge nozzle so as to maintain a state in which it is positioned in front of the discharge port of the discharge nozzle in the relative direction of advance.
A second invention is a discharge nozzle that discharges a viscous fluid, and an advancing device that supports the discharge nozzle in a state where the discharge port is close to the surface of the object to be coated and relatively advances along the surface of the object to be coated. The gist of the viscous fluid applying apparatus including the above is to provide a viscous fluid preceding detection apparatus that detects that the viscous fluid is positioned in front of the discharge port of the discharge nozzle. When the viscous fluid in front of the ejection port is detected, it may be detected only that the viscous fluid is in the front, or the width, height, etc. of the viscous fluid in the front may be detected. A third aspect of the present invention is characterized in that a coating state detection device that detects a coating state of the coated viscous fluid is provided behind the discharge nozzle of the viscous fluid coating device of the second aspect.

[0005]

According to the first aspect of the invention, when the viscous fluid discharged from the discharge nozzle is relatively advanced along the surface of the object to be coated and a part of the viscous fluid is discharged from the discharge port of the discharge nozzle. When kept in a state of being positioned further forward, generation of bubbles between the viscous fluid and the object to be applied is avoided (note that the following description regarding the relative progress of the discharge nozzle and the object to be applied). In the description, the application target is fixed and the discharge nozzle moves, but this is for convenience, and the application target may move, or both may move). For example, as shown in FIGS. 18 and 19, when a part of the viscous fluid 82 discharged into the groove 80 is positioned in front of the discharge port 85 of the discharge nozzle 84,
At least the space between the discharge nozzle 84 and the groove bottom surface 86 is filled with the viscous fluid 82. The viscous fluid 82 does not appear in front of the ejection port until the viscous fluid 82 is filled during this period. Therefore, if a part of the viscous fluid 82 is kept in front of the ejection port 85 of the ejection nozzle 84 during the movement of the ejection nozzle 84, the space between the ejection nozzle 84 and the groove bottom surface 86 is always filled with the viscous fluid 82. The coating progresses in this state. Therefore, no gap is formed between the viscous fluid 82 and the groove bottom surface 86, and the generation of bubbles is avoided. The same applies to the case of coating other than the groove.

In the second invention, when the viscous fluid discharged from the discharge nozzle is applied along the surface of the object to be coated, the viscous fluid may be located in front of the discharge port of the discharge nozzle. It is detected by the preceding detection device.
By providing such a viscous fluid advance detection device,
It is possible to confirm whether or not the viscous fluid is kept in a state of being positioned in front of the discharge port of the discharge nozzle. Then, if a part of the viscous fluid is kept in front of the discharge port, the discharge is continued, and if it is not kept, the application is stopped or a notification is given. can do. Further, by connecting a control device for controlling the viscous fluid application device and the viscous fluid preceding detection device, the ejection speed, the ejection nozzle moving speed, etc. are controlled according to the state of the viscous fluid in front of the ejection port. It is also possible.

In the third aspect, the application state of the viscous fluid, for example, the height of the application surface or the application width is detected by the application state detecting device. The coating state is detected to confirm whether or not the coating has been successfully performed. When used in combination with the viscous fluid advance detection device of the second invention, it is possible to grasp the relationship between the state of the viscous fluid positioned in front of the discharge port and the application state. For a viscous fluid with a predetermined viscosity, the state of the viscous fluid in front of the discharge port that makes the coating state appropriate at the predetermined relative movement speed is investigated in advance, and the discharge speed can be controlled so that the state is appropriate. Therefore, it is possible to apply a proper amount of viscous fluid while avoiding generation of bubbles. Similarly, the moving speed of the discharge nozzle may be controlled so that the coating state is appropriate at the scheduled discharge speed.

Further, the application state detecting device and the viscous fluid preceding detection device are used together, and by connecting these devices and the control means of the viscous fluid applying device, the device is positioned in front of the discharge port according to the application state. It is possible to control the state of the viscous fluid. For example, when observing only the state of the viscous fluid in front of the discharge nozzle and controlling the discharge speed of the viscous fluid based on that information, if the viscosity of the viscous fluid changes, it is preset for the planned viscosity. Even when discharging at the discharge speed, etc., the information regarding the state of the viscous fluid in front of the discharge nozzle is different from the planned one, and the discharge speed and the like are controlled based on the information different from the planned one. The viscous fluid cannot be applied properly.
However, if both the state of the viscous fluid located in front of the ejection port and the application state are detected and the ejection speed and the like are controlled based on these information, the ejection speed and the like of the viscous fluid can be controlled according to the application state. Therefore, it becomes possible to perform good coating.

By using the application state detecting device and the viscous fluid preceding detection device in combination, the data for determining the optimum condition for applying the viscous fluid can be easily obtained. Appropriately change various conditions such as viscosity of viscous fluid, discharge speed, relative movement speed of discharge nozzle and object to be coated, nozzle diameter, and groove width and depth when applying to a groove. The state of the viscous fluid and the applied state in front of the ejection port below are observed. Since the difference in various conditions is reflected in the state of the viscous fluid in front of the discharge port and the coating state, it is possible to determine the optimum conditions for performing favorable coating based on these data.

It should be noted that the detection by the viscous fluid preceding detection device and the coating state detection device can be performed by using an optical type sensor, an ultrasonic type sensor or a contact type sensor, but in view of handling and detection accuracy. It is preferable to use an optical sensor.

[0011]

As described above, according to the first aspect of the present invention, by locating a part of the viscous fluid in front of the discharge port, it is possible to favorably avoid the generation of bubbles. In the second invention, by detecting that the viscous fluid is located in front of the discharge port, it becomes easy to confirm that a part of the viscous fluid is kept in front of the discharge port. The application can be adjusted based on the confirmed result, and it becomes possible to favorably avoid the generation of bubbles.
In the third invention, by detecting the state of the viscous fluid in front of the ejection port and detecting the application state, it becomes possible to determine the state of the viscous fluid in front of the ejection port when an appropriate application state is achieved. Therefore, it is possible to easily obtain a good coating state without bubbles.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. As shown in FIG. 1, a robot 12 and a viscous fluid supply device 14 are provided on a base 10. The robot 12 is a so-called industrial robot, and performs various works based on preset conditions. The robot 12 is provided with an arm 16 that operates on a predetermined locus based on information taught by a copying method or the like, and a viscous fluid discharge device 18 is provided at the tip of the arm 16.
Is attached.

The viscous fluid supply device 14 stores a coating viscous fluid (hereinafter, simply referred to as viscous fluid), and the stored viscous fluid is stored in a viscous fluid discharge device 18 provided in the robot 12 as needed. It is a supply device. The viscous fluid discharge device 18 and the viscous fluid supply device 14 are connected to the hose 20.
The viscous fluid is mainly connected to the viscous fluid supply device 14, and the viscous fluid is transferred from the viscous fluid supply device 14 to the viscous fluid discharge device 18 via the hose 20 by the pump provided in the viscous fluid supply device 14. Inside the viscous fluid discharge device 18, a container 21 for storing a viscous fluid, and the container 21
A container weight measuring device 22 for measuring the weight of the container, a metering pump for quantitatively discharging the stored viscous fluid, and a discharge nozzle 2 for discharging the viscous fluid at the tip.
3 is attached. In addition, the viscous fluid discharge device 18
A viscous fluid preceding detection device 24 is attached to the front side in the nozzle advancing direction, and a coating state detection device 26 is attached to the rear side in the nozzle advancing direction.

Here, the case where a sealant is applied as a viscous fluid into the groove 28 of the seam of the panel of the automobile body will be described. The sealant is a white material and the panels are almost steel colored. The sealant may be of other colors such as black.Examples of use include when applying a liquid gasket made of white room temperature vulcanizing silicone rubber to a black oil pan, or to a black engine rubber for a silver engine head cover gasket. It may be possible to apply.

The tip of the discharge nozzle 23 is close to the groove 28 formed on the surface of the object to be coated, and the viscous fluid supplied to the viscous fluid discharge device 18 flows from the discharge port 29 of the discharge nozzle 23 to the groove 28. Is discharged along. At that time, the viscous fluid preceding detection device 24 detects the extent to which the discharged viscous fluid 30 projects forward from the discharge port 29, and the discharge nozzle 23
The coating state on the rear side is detected by the coating state detection device 26. The detected information is the control device 32 shown in FIG.
Sent to. The viscous fluid preceding detection device 24 and the coating state detection device 26 will be described in detail later.

The control device 32 uses the viscous fluid preceding detection device 2
4 and the coating state detection device 26 and the like are connected to the input port 34, and the robot 12, the viscous fluid supply device 14, the viscous fluid discharge device 18 and the like are connected to the output port 36.
And a computer 38, and the computer 3
8 includes a CPU 40, a ROM 42 and a RAM 44.

The information detected by the viscous fluid preceding detection device 24, the coating state detection device 26, etc. is sent to the computer 38 via the input port 34, and various programs are executed based on the information. Various control commands determined by the execution of the program pass through the output port 36 and the robot 12, the viscous fluid supply device 14, and the viscous fluid discharge device 1
8 and the like to control the operation of each device.

The program executed by the computer 38 is stored in the ROM 42 shown in FIG. ROM4
2 includes a discharge control routine memory 46, a front viscous fluid amount calculation routine memory 48, a front viscous fluid amount allowable range memory 50, a front viscous fluid amount correction rear viscous fluid amount correction value memory 51, and a rear viscous fluid amount calculation. Routine memory 5
2, various memories such as a rear viscous fluid amount allowable range memory 54, a rear viscous fluid amount correction value memory 55, a nozzle moving speed correction routine memory 57, a viscous fluid discharge speed correction routine memory 58, and a loop execution reference number memory 62 are formed. ing.

Here, the discharge control routine memory 46 is
A memory that stores a discharge control routine that controls the robot 12, the viscous fluid supply device 14, the viscous fluid discharge device 18, and the like based on the amount of viscous fluid in front of the discharge port 29 and the amount of viscous fluid behind the discharge nozzle 23. is there. The forward viscous fluid amount calculation routine memory 48 uses the viscous fluid preceding detection device 2
4 is a memory in which a front viscous fluid amount calculation routine for calculating the viscous fluid amount in front of the discharge port 29 based on the information of No. 4 is stored. The front viscous fluid amount allowable range memory 50 is a memory in which a permissible range of the viscous fluid amount in front of the ejection port 29 is stored, and here, the minimum permissible amount of the viscous fluid 30 in front of the ejection port 29 is stored. There is. In the rear viscous fluid amount correction value memory 51 for correcting the front viscous fluid amount, the detection result of the front viscous fluid amount is smaller than the minimum allowable amount of the viscous fluid 30 in front of the discharge port 29, and it is necessary to correct the application amount of the viscous fluid 30. In this case, the memory stores the rear viscous fluid amount necessary to eliminate the detected shortage of the front viscous fluid amount, that is, the correction value of the application amount. The rear viscous fluid amount calculation routine memory 52 is a memory in which a rear viscous fluid amount calculation routine for calculating the rear viscous fluid amount on the basis of the information of the coating state detection device 26 is stored. The rear viscous fluid amount allowable range memory 54 stores the allowable range of the viscous fluid amount behind the discharge nozzle 23, that is, the maximum allowable application amount which is the maximum value of the allowable range of the application amount of the viscous fluid 30 and the minimum value of the allowable range. This is a memory that stores a certain minimum allowable application amount. The rear viscous fluid amount correction value memory 55 allows the amount of viscous fluid behind the discharge nozzle 23 to fall within an allowable range of the amount of viscous fluid 30 stored in the rear viscous fluid amount allowable range memory 54. Is a memory that stores a value to be corrected, and a correction value ΔV1 (having a negative value) that reduces the application amount when the application amount of the viscous fluid 30 is larger than the maximum allowable application amount, and the minimum acceptable value. ΔV2 which is a correction value for increasing the coating amount when it is smaller than the coating amount
(Having a positive value) are stored. The nozzle movement speed correction routine memory 57 is a memory that stores a nozzle movement speed correction routine that corrects the movement speed of the ejection nozzle 23. Viscous fluid discharge speed correction routine memory 5
A memory 8 stores a viscous fluid discharge speed correction routine for correcting the viscous fluid discharge speed. The loop execution reference number memory 62 stores the reference number of execution of a specific loop described later in the discharge control routine in a state where the viscous fluid 30 is not detected in front of the discharge port 29 during the execution of the discharge control routine. It is a memory.

Various data generated during the execution of the program stored in the ROM 42 are stored in the RAM 44. As shown in FIG. 4, the RAM 44 stores a loop execution count that stores the number of executions of the ejection control routine in a state where the viscous fluid 30 is not detected in front of the ejection port 29 when the ejection control routine described later is executed. A memory used for various calculation processes is formed, including the number memory 64.

The detection of the application state of the viscous fluid 30 by the viscous fluid preceding detection device 24 and the application amount detection device 26 will be described in detail.

As shown in FIGS. 5 and 6, the viscous fluid preceding detection device 24 and the coating amount detection device 26 are both a CCD camera 66 and an annular light source device 68 provided adjacent to the CCD camera 66. It is configured. CCD camera 6
Reference numeral 6 captures a linear image of the viscous fluid in the groove width direction at an imaging position determined by the state of attachment to the viscous fluid discharge device 18. The light emitted from the light source device 68 is reflected on the surface of the viscous fluid 30, and the reflection state that changes in the groove width direction is C
The state of the viscous fluid 30 is known by detecting it with the CD camera 66. The CCD camera 66 is provided so as to be able to capture an image in a region slightly wider than the groove width, and detects the height and width of the viscous fluid 30.

The height of the viscous fluid 30 is determined by the CCD camera 66.
Use the automatic focus adjustment function of to detect. Good application
Of the discharge nozzle 23 and the front of the discharge port 29
The height of the viscous fluid 30 at the rear, for example, the discharge shown in FIG.
Height h of viscous fluid in front of mouth 29 _fAnd the discharge port 29
Height of rear viscous fluid h_bThe forward and backward reference viscosity
The height of the fluid should be set in front of and behind the discharge nozzle 23.
The focus of the attached CCD camera 66 respectively
The camera lens at that time according to the standard viscous fluid height of
The position is used as each reference lens position. Automatic focus adjustment
For cameras with functions, the lens position is automatically adjusted.
When adjusting the focus,
By detecting the change in lens position of
You can know if it exists in the position. As shown in Figure 7.
The viscous fluid surface is higher than the standard viscous fluid height.
Or the viscous fluid surface is the reference viscous fluid as shown in FIG.
When the height is lower than the height, the above viscous fluid table
Lens position and reference level when the surface is in focus
The height of the viscous fluid 30 by comparing
Standard viscous fluid height h_f,h_bDeviation from
And the height of the viscous fluid 30 can be detected.
Of.

The width of the viscous fluid 30 is detected by subjecting the image from the CCD camera 66 to image processing. The width is detected by discriminating the viscous fluid portion based on the difference in shade on the image between the viscous fluid 30 and the portion that is not the viscous fluid 30. The front viscous fluid amount calculation routine and the rear viscous fluid amount calculation routine are executed based on the height and width of the viscous fluid 30 thus detected. In these routines, the discharge port 29
The cross-sectional area of the viscous fluid at the photographing position in front of and in the rear of the discharge nozzle 23 is calculated, and the amount of viscous fluid in front of the discharge port 29 and behind the discharge nozzle 23 is obtained based on the cross-sectional area. Here, the amount of viscous fluid in front of the ejection port 29 is the total amount of viscous fluid in front of the ejection port, and is the cross-sectional area of the viscous fluid at the imaging position and the amount of viscous fluid in front of the ejection port 29 which are obtained in advance. Obtained from the relationship. Further, the amount of viscous fluid behind the discharge nozzle 23 is determined by the groove 28.
Is the amount of viscous fluid per unit length of.

Next, the discharge control of the viscous fluid will be described with reference to the flow chart of the discharge control routine shown in FIG.
When the preparation for applying the viscous fluid is completed and a discharge control start command for the viscous fluid is issued from an operation panel (not shown), the discharge control routine stored in the discharge control routine memory 45 is read. In executing this discharge control routine,
Although various routines stored in the ROM 42 are executed, these routines are not directly related to the present invention, and therefore illustration and description thereof are omitted. Also, each of these routines is read from the memory of the ROM 42 each time it is executed, but in order to avoid complication of the description, the description of the memory name and the code at the time of reading is omitted below.

First, step 1 (hereinafter referred to as S1).
It is determined in step 2 and subsequent steps) whether or not the viscous fluid 30 is in front of the discharge port 29 based on the information from the viscous fluid advance detection device 24. When the viscous fluid 30 is present in the front, the application amount of the viscous fluid 30 is controlled after S2, and when the viscous fluid 30 is not present, the device abnormality is detected after S17. The steps after S17 will be described later. When the viscous fluid 30 is in front of the ejection port 29, the front viscous fluid amount calculation routine is executed in S2, and the ejection port is calculated based on the height and width of the viscous fluid 30 detected by the viscous fluid preceding detection device 24. The amount of viscous fluid in front of 29 is calculated. In S3, the calculated viscous fluid amount in front of the discharge port 29 is compared with the minimum allowable amount of viscous fluid amount in front of the discharge port 29 stored in the front viscous fluid amount allowable range memory 50. When the calculated viscous fluid amount is less than the minimum allowable amount, the shortage amount is calculated in S4, and then the backward viscosity required to compensate for this shortage amount in S5 based on the calculated shortage amount value. The correction value of the fluid amount is obtained, and S11 is executed. The relationship between the shortage amount of the viscous fluid in front of the discharge port 29 and the correction value necessary for compensating the shortage amount to obtain the proper rear viscous fluid amount is obtained in advance, and the shortage is determined based on the relation. The correction value of the amount of rear viscous fluid required to compensate is obtained. For this correction value, the correction value stored in the front viscous fluid amount correction rear viscous fluid amount correction value memory 51 of the ROM 42 is referred to.

When the amount of viscous fluid in front of the discharge port 29 is equal to or larger than the minimum allowable amount, the rear viscous fluid amount calculation routine is executed in S6 to calculate the amount of viscous fluid behind the discharge nozzle 23, and then S7 is executed. To be done. In S7, the calculated viscous fluid amount behind the discharge nozzle 23 is compared with the maximum allowable application amount and the minimum allowable application amount stored in the backward viscous fluid amount allowable range memory 54. If the calculated amount of viscous fluid is between the maximum allowable application amount and the minimum allowable application amount and is within the allowable range, the routine is terminated as it is, and if it is not within the allowable range, S8 is executed. In S8, it is determined whether or not the calculated viscous fluid amount is larger than the maximum allowable coating amount. If it is large, a correction is made to reduce the coating amount in S9, and if it is small, a correction is made to increase the coating amount in S10. Done. At S9, ΔV1 stored in the rear viscous fluid correction value memory 55 of the ROM 42 is added to the current application amount V, and at S10, ΔV2 similarly stored in the rear viscous fluid correction value memory 55 is added to the current application amount. Be done. S11 is executed after S9 or S10 is executed.
Is executed.

In S11, the correction amount of the nozzle moving speed of the viscous fluid coating device required to achieve the corrected coating amount is calculated, and in S12, the nozzle moving speed is adjusted within the adjustment limit of the nozzle moving speed. . The adjustment limit of the nozzle moving speed may be determined in consideration of productivity or may be determined from device performance. In S13, it is determined whether or not the necessary application amount of the viscous fluid 30 can be obtained only by adjusting the nozzle moving speed performed in S12, and if it is obtained, in S16, after the elapse of a predetermined time, the routine is executed. Finish execution. If the required coating amount cannot be obtained, S1
In step 4, the correction amount of the discharge speed of the viscous fluid 30 is calculated, and in step S15, the correction speed of the viscous fluid 30 is adjusted.
After the elapse of a predetermined time, the routine is terminated. The nozzle moving speed is corrected by executing the nozzle moving speed correcting routine, and the viscous fluid discharge speed is corrected by executing the viscous fluid discharging speed correcting routine.

If there is no viscous fluid 30 in front of the discharge port 29 in S1, a nozzle movement stop command is issued in S17 to stop the movement of the discharge nozzle 23. It is waited for the viscous fluid 30 to come out. In S18, the number N of times the nozzle movement stop command is issued (this number N is the number of times of execution of a loop described later) is counted. The number of times N is increased each time a nozzle movement stop command is issued. The number N is cleared when the viscous fluid 30 is detected in front of the discharge port 29 in S1. In S19, the number N is compared with the reference number stored in the loop execution reference number memory 62. If the number of times N is equal to or greater than the reference number of times, an abnormality check and warning of the viscous fluid discharge device 18 are performed after S20
If the reference number is not reached, S1 is executed again. When the viscous fluid 30 is not detected in front of the discharge port 29 in S1, the execution of the loop of S1-S17-S18-S19 is repeated, and when the loop execution count N reaches the reference count, S2 is executed.
0 is executed.

In S20, the weight of the container 21 in the viscous fluid discharge device 18 is measured by the container weight measuring device 22, and it is determined whether or not the viscous fluid 30 remains in the container. If the viscous fluid 30 remains, it is determined that the ejection nozzle 23 is clogged and thus the ejection of the viscous fluid 30 is hindered. In S22, the nozzle clogging lamp provided on the control plate (not shown) is turned on. On the other hand, viscous fluid 3
If 0 does not remain, the viscous fluid out lamp is turned on in S21. After that, in order to further clearly indicate the abnormality, the abnormality lamp is turned on in S23 and the execution of the routine is stopped.

As described above, by adjusting the viscous fluid discharge speed and the nozzle moving speed so that the viscous fluid 30 of a predetermined amount or more always exists in front of the discharge port 29, the groove 28 is formed.
It is possible to avoid the generation of bubbles between the bottom surface of the and the viscous fluid 30. Further, by further detecting the amount of viscous fluid applied to the rear of the discharge nozzle 23 and adjusting the amount of applied viscous fluid, a good application state can be obtained.

Although one embodiment of the present invention has been described in detail above, the present invention is not limited to this embodiment. For example, although the CCD camera 66 that captures a linear image is used as the viscous fluid preceding detection device 24 and the coating state detection device 26, it is not necessary to use a camera that captures a linear image, and the entire image is captured. You may use the CCD camera which does. Further, although the amount of front viscous fluid and the amount of rear viscous fluid were detected from both width and height, the amount of front viscous fluid or the amount of rear viscous fluid may be detected by only one of them, and both of them may be detected. The forms may be different.

Both detectors 24 and 26 are not necessarily C
It is not necessary to use the CD camera 66, and FIGS.
The contact type strain sensor 70 shown in FIG. 5 may be used. Figure 1
As shown in FIG. 0, the strain sensor 70 is attached to the front and rear opposite positions in the traveling direction of the discharge nozzle 23 indicated by the arrow in the figure, and the strain sensor 70 is strained when it is bent by the flow of the viscous fluid 30. Is detected to detect the coating state of the viscous fluid 30. As shown in FIGS. 10 and 11, if a large amount of the viscous fluid 30 is projected forward, the strain amount of the strain sensor 70 provided in the forward direction is large, and if a small amount is projected as shown in FIGS. Is small and does not distort if there is no protrusion to the front as shown in FIGS. 14 and 15. Therefore, the amount of viscous fluid in front of the discharge port 29 can be detected by detecting this amount of distortion.
The same applies to the detection of the amount of viscous fluid behind the discharge nozzle 23. Since the strain sensor 70 is of a contact type, the contact portion may enter the viscous fluid and leave a locus on the application surface.
It can be avoided by increasing the difference in surface tension from 0.

Further, an ultrasonic transmitter and an ultrasonic receiver may be attached to the discharge nozzle 23 to detect the coating state of the viscous fluid 30 from the information of the ultrasonic waves reflected by the viscous fluid, or irradiate light. However, the application state of the viscous fluid 30 may be detected by measuring the intensity of the reflected light. As an example of using ultrasonic transmitters and receivers, a plurality of transmitters and receivers are arranged in a line so as to have a one-to-one correspondence, and ultrasonic waves transmitted from the corresponding transmitters are received. There is a device that detects the state of a viscous fluid. Furthermore, the viscous fluid advance detection device 24 and the coating state detection device 26 do not need to have the same detection mechanism.

Further, although the cross-sectional shape of the discharge nozzle is circular in this embodiment, it is not limited to this and various shapes, for example, a discharge nozzle having a slit-shaped discharge port can be used.

In the above embodiment, when correcting the viscous fluid application amount, fine correction is performed by correcting the nozzle moving speed, and by limiting the correction range of the nozzle moving speed to a fixed range, the target nozzle moving speed is increased. The deviation from the speed was prevented, and the insufficient viscous fluid application amount was corrected by correcting the viscous fluid discharge speed, but the relationship between the nozzle movement speed correction and the viscous fluid discharge speed correction may be reversed. It is possible.

Further, it is necessary to set the reference values for the nozzle moving speed and the viscous fluid discharge speed, and always calculate the deviation rate of the actual values of both from the reference value to correct the viscous fluid application amount. In this case, the viscous fluid application amount may be corrected by correcting the direction in which the absolute value of the deviation rate decreases in the nozzle movement speed or the viscous fluid discharge speed, whichever can achieve the purpose. It is possible. In both cases, when the absolute value of the deviation rate becomes small, the viscous fluid application amount may be corrected by correcting the larger absolute value of the deviation rate. Further, it is possible to fix one of the nozzle moving speed and the viscous fluid discharge speed and correct the viscous fluid application amount by only the other.

The discharge control routine of the above embodiment is
The viscous fluid application amount is controlled within a range in which the change in the fluidity of the viscous fluid 30 due to disturbance is small to secure the viscous fluid amount in front of the discharge port. (Variation) is allowed, but the discharge control routine is not limited to this. For example, when the application conditions such as the viscous fluid discharge speed are different for each viscous fluid having a different viscosity, the relationship between the viscous fluid quantity in front of the discharge port and the viscous fluid quantity in the back of the nozzle is obtained in advance, and the viscous fluid is calculated based on the relationship. Three
By controlling the coating conditions according to the viscosity of 0,
The viscous fluid application amount may be brought close to a desired value regardless of the change in the fluidity of the viscous fluid. In addition, the present invention can be implemented in variously modified and improved modes based on the knowledge of those skilled in the art without departing from the scope of the claims.

[Brief description of drawings]

FIG. 1 is a front view schematically showing a viscous fluid application device that is an embodiment of the present invention.

FIG. 2 is a diagram conceptually showing a configuration of a control device of the viscous fluid application device.

FIG. 3 is a diagram conceptually showing a structure of a memory area of a ROM of the control device.

FIG. 4 is a diagram conceptually showing a structure of a memory area of a RAM of the control device.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a side sectional view showing the same viscous fluid application state as in FIG.

FIG. 7 is a side cross-sectional view showing a coating state in an excessive viscous fluid supply state in the above embodiment.

FIG. 8 is a side cross-sectional view showing a coating state in an excessively viscous fluid supply state in the above embodiment.

FIG. 9 is a flowchart of a discharge control routine used in the above embodiment.

FIG. 10 is a diagram corresponding to FIG. 5 showing a viscous fluid application state in an example different from the above example.

11 is a side sectional view showing the same viscous fluid application state as in FIG.

12 is a plan sectional view showing a coating state different from the coating state of FIG.

FIG. 13 is a side sectional view showing the same viscous fluid application state as in FIG.

FIG. 14 is a cross-sectional plan view showing another coating state different from the coating state of FIG.

FIG. 15 is a side sectional view showing the same viscous fluid application state as in FIG.

FIG. 16 is a view of a viscous fluid applied state by a conventional applying method as viewed from above the groove.

FIG. 17 is a side sectional view showing the same viscous fluid application state as in FIG.

FIG. 18 is a view of a coating state of a viscous fluid according to the coating method of the present invention viewed from above the groove.

FIG. 19 is a side sectional view showing the same viscous fluid application state as in FIG.

[Explanation of symbols]

 18 Viscous Fluid Discharge Device 23 Discharge Nozzle 24 Viscous Fluid Advance Detection Device 26 Coating State Detection Device 28 Groove 30 Viscous Fluid 66 CCD Camera 68 Light Source Device 70 Strain Sensor

Front page continuation (72) Inventor Hisao Yamaguchi 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd.

Claims (3)

[Claims] 1. A method of applying a viscous fluid while advancing a discharge port of a discharge nozzle for discharging a viscous fluid to a surface of an object to be coated and relatively advancing along the surface, wherein the discharge nozzle discharges the viscous fluid. A part of the viscous fluid is kept in a state of being positioned in front of the ejection port of the ejection nozzle in the relative direction of movement, and the viscous fluid application method. 2. A discharge nozzle which discharges a viscous fluid, and a progress device which supports the discharge nozzle in a state where its discharge port is close to the surface of the object to be coated and relatively advances along the surface of the object to be coated. A viscous fluid application device comprising: a viscous fluid preceding detection device that detects that the viscous fluid is positioned ahead of a discharge port of the discharge nozzle in a discharge nozzle advancing direction. 3. The viscous fluid coating device according to claim 2, further comprising a coating state detection device that is disposed behind the discharge nozzle in the traveling direction to detect the coating state of the coated viscous fluid.