JP2019081123A - Coating nozzle - Google Patents

Abstract

To efficiently carry out coating in a stable discharge pattern even in a case where coating is carried out along a bent trajectory in a coating nozzle.SOLUTION: A coating nozzle 1 discharges a high viscous material P from a discharging part 3. The coating nozzle comprises: a body 10 having: supply holes 11, 12, 13 through which the high viscous material P is supplied; a tapering hole 14 communicating with the supply holes 11, 12, 13 and increasing in diameter toward a leading end thereof; an air hole 18 for introducing outside air; and cylindrical members 20, 30 each of which is provided in the body 10, has a through-hole 33 and is provided such that an outer peripheral surface 23a of a leading end part 23 thereof faces a tapering surface 14a. The discharging part 3 is constituted of an annularly cross-sectional slit formed between the tapering surface 14a and the outer peripheral surfaces 23a of the cylindrical members 20, 30, and the air hole 18 and the through-hole 33 are in communication with each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an application nozzle which discharges a supplied high viscosity material and applies the material to a surface to be coated of an object.

  Conventionally, for example, coating is performed to apply a high-viscosity material to a workpiece from various directions using a coating nozzle attached to the tip of a robot arm. In order to allow the high viscosity material to reach the work, it is necessary to increase the discharge flow velocity. However, since the viscosity of the high-viscosity material decreases as the discharge flow velocity increases, it becomes mist when the discharge flow velocity is increased, and there is a problem that the application range is expanded beyond the target application range.

  Therefore, for example, Patent Document 1 discloses an application nozzle in which the length in the radial direction of the second flow path formed of a substantially fan-shaped slit is set longer on both sides of the substantially fan-shape than the central portion. According to the patent document 1, since the second flow path is a substantially fan-shaped slit, the resistance becomes substantially uniform over the entire area of the second flow path, and the shear rate of the high-viscosity material is It is said that the decrease in viscosity can be suppressed and the formation of mist of the high-viscosity material can be suppressed by decreasing the viscosity.

  However, as shown in FIG. 8A, since the application nozzle of Patent Document 1 which discharges the high-viscosity material from the linear slit seen from the nozzle tip side has directivity, as shown in FIG. When coating is performed while moving the coating nozzle 101 in the direction orthogonal to the above, it is possible to coat the target coating range, but as shown in FIG. 8 (b), coating in the direction parallel to the slit 103 is performed. If painting is performed while moving the nozzle 101, only the width of the slit 103 can be painted. Therefore, when coating is performed in a curved track such as the corner portion 50a (see FIG. 8C) of the work 50, it is considered that the direction change of the coating nozzle 101 itself is performed at the corner portion 50a, for example. There is a problem that the coating thickness becomes thick at the corner portion 50a. In particular, when coating is performed from below, liquid dripping occurs at a portion where the coating thickness is thickened, and the portion where the liquid drip occurs is solidified There is a problem that it becomes easy to peel off.

  Therefore, for example, when coating is performed in a track bent at a right angle, the coating nozzle 101 that performs coating while moving in the direction (X direction) orthogonal to the slit 103 is indicated by a dashed arrow in FIG. As it is moved to the outside of the work 50 as it is in the X direction, direction change is performed outside the work 50 so that the direction orthogonal to the slit 103 coincides with the Y direction perpendicular to the X direction. Coating is often performed while moving the coating nozzle 101 in the Y direction. However, since such a method involves movement operation and movement time outside the workpiece 50, the problem that the operation efficiency of the robot arm is poor, and because the corner portion 50a is coated twice and the coating thickness becomes thick, There is a problem that the above-mentioned dripping of the liquid and peeling resulting therefrom occur.

  Therefore, when coating is performed with a curved track, a coating nozzle capable of coating with a discharge pattern having no directivity, specifically, for example, a high viscosity material (sealer agent) as in the coating nozzle of Patent Document 2 It is conceivable to adopt one that discharges in the form of a truncated cone.

JP 11-110027 A JP 2002-239421 A

  As in the case of Patent Document 2 described above, in the case of a coating nozzle that discharges a high viscosity material in a curtain shape of a truncated cone, the target coating range is coated regardless of the direction in which the coating nozzle is moved. For example, even when coating is performed in a track that bends at a right angle or an acute angle, it is not necessary to change the direction of the coating nozzle itself (see FIG. 7 (b)). I can paint well.

  However, when the high viscosity material is discharged in the form of a truncated cone, it is divided by the surface to be coated (for example, the upper surface) of the work, the high viscosity material for the curtain (side surface), and the tip of the application nozzle (for example, the lower surface) When the closed space having a truncated cone shape is formed, the curtain-like high viscosity material has a flow velocity, so a negative pressure region is generated in the closed space, and the high viscosity material is drawn into the closed space and disturbed. There is a problem that the discharge pattern is not stable.

  The present invention has been made in view of such a point, and an object of the present invention is to provide a technology for efficiently performing coating with a stable discharge pattern even when coating is performed in a curved track in an application nozzle. It is in.

  In order to achieve the above object, in the coating nozzle according to the present invention, a high viscosity material is discharged from a slit having an annular cross section in a curtain shape of a truncated cone, a coated surface, a curtain shape high viscosity material and a tip of the coating nozzle The closed space enclosed by the above is communicated with the outside air through a hole provided in the coating nozzle.

  Specifically, the present invention is directed to a coating nozzle that discharges the supplied high viscosity material from the discharge unit.

  Then, the application nozzle is formed with a supply hole to which the high viscosity material is supplied, a tapered hole which is in communication with the supply hole and whose diameter increases toward the tip, and an air hole for introducing the outside air. A nozzle body portion, and a tubular member provided in the nozzle body portion and having a through hole, the outer peripheral surface of the tip end portion being inclined so as to face the tapered surface of the tapered hole, the discharge The portion is constituted by a slit having an annular cross section formed between the tapered surface of the tapered hole and the outer peripheral surface of the cylindrical member, and the air hole and the through hole are in communication with each other. It is a feature.

  According to this configuration, the high viscosity material supplied to the supply hole of the nozzle main body reaches the tapered hole communicating with the supply hole, and then between the tapered surface of the tapered hole and the outer peripheral surface of the cylindrical member The high viscosity material can be sprayed in the form of a truncated cone onto the surface to be coated of the work, since it is discharged through the slit (discharge part) having an annular cross section. As described above, since the high-viscosity material is sprayed in a curtain shape (cone shape) of a truncated cone, in other words, with a non-directional discharge pattern, the coating nozzle itself is applied even when coating is performed with a trajectory bent at right angles or acute angles, for example. Since it is not necessary to perform the change of direction, the coating efficiency can be improved, for example, because the robot arm or the like is not subjected to unnecessary operation or is not coated twice.

  Here, when the high viscosity material is sprayed in a curtain shape of a truncated cone, a negative pressure region is generated in a closed space surrounded by the coated surface, the high viscosity material in a curtain shape of the truncated cone and the tip of the application nozzle, and the discharge pattern In the present invention, the air hole for introducing the outside air formed in the nozzle main body and the through hole of the cylindrical member whose front end faces the closed space communicate with each other in the present invention. Thus, it is possible to suppress a pressure difference between the internal pressure of the closed space and the external pressure. Therefore, the curtain-like high-viscosity material can be prevented from being drawn into the closed space and disturbed, whereby the discharge pattern when spraying the high-viscosity material can be stabilized.

  As described above, according to the coating nozzle of the present invention, even when coating is performed on a curved track, coating can be efficiently performed with a stable discharge pattern.

It is a figure showing typically the application nozzle concerning the embodiment of the present invention. It is the figure which looked at the application | coating nozzle from the front end side. It is sectional drawing of the III-III line of FIG. 2 which shows a coating nozzle typically. It is a figure which shows a body typically, the figure (a) is the figure which looked at the body from the proximal end side, the figure (b) is a sectional view of the bb line of the figure (a). is there. It is a figure which shows a chip | tip typically, the figure (a) is sectional drawing of a chip | tip, and the figure (b) is the figure which looked at the chip | tip from the front end side. It is a figure which shows a countersunk screw typically. It is a figure which illustrates typically the coating pattern at the time of coating the discharge pattern of a coating nozzle, and a corner part. It is a figure which illustrates typically the coating pattern at the time of coating the discharge pattern and the corner part of the conventional application nozzle.

  Hereinafter, an embodiment for carrying out the present invention will be described based on the drawings.

  FIG. 1 is a view schematically showing the coating nozzle 1 according to the present embodiment, and FIG. 2 is a view of the coating nozzle 1 viewed from the tip side. The coating nozzle 1 is attached to the end of a robot arm (not shown), and the high viscosity material P supplied from the container (not shown) to the proximal side via a pump (not shown) or the like. (See white arrow in FIG. 1) from the discharge part 3 constituted by the slit having an annular cross section shown in FIG. 2, as shown in FIG. It sprays on the painted surface of The robot arm is configured to move the coating nozzle 1 freely with respect to the workpiece 50, whereby the coating nozzle 1 has a conical shape with a high viscosity material P relative to the workpiece 50, as shown in FIG. It is possible to spray from below with a curtain-like discharge pattern.

  Examples of the high-viscosity material P include a sealer which brings the base and the paint into close contact, an undercoat agent which is a rust-preventive paint, a damping paint having a function of attenuating vibration and noise, and an adhesive. be able to.

-Structure of coating nozzle-
FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2 and schematically showing the coating nozzle 1. As shown in FIG. 3, the coating nozzle 1 has a body (nozzle main body) 10 whose base end is attached to the tip of the robot arm, a tip 20 assembled to the tip of the body 10, and a tip 20 as the body 10. And a countersunk screw 30 for fixing to.

  FIG. 4 is a view schematically showing the body 10, and FIG. 4 (a) is a view of the body 10 viewed from the base end side, and FIG. 4 (b) is a view taken along the line b-- of FIG. It is sectional drawing of b line. The body 10 is made of metal and is formed into a substantially cylindrical outer shape. Hereinafter, the longitudinal direction of the body 10 having a substantially cylindrical outer shape is referred to as an axial direction, the right side of FIG. 4B is referred to as a proximal side, and the left side of FIG. 4B is referred to as a distal side.

  As shown in FIGS. 4A and 4B, on the proximal end side of the body 10, there is formed an introduction hole 11 having a circular cross-section that opens in the proximal end side and extends in the axial direction. The high viscosity material P is supplied (introduced) from the container to the introduction hole 11 via a pump or the like.

  On the other hand, on the front end side of the body 10, as shown in FIG. 4B, a tapered hole 14 having a circular cross-section which is opened on the front end side and extends in the axial direction is formed. The tapered hole 14 is formed to increase in diameter toward the distal end side (concave toward the proximal end), and therefore, the tapered surface 14a that divides the tapered hole 14 is inclined in a diverging manner. ing.

  On the base end side of the tapered hole 14, a collecting hole 13 having a circular cross-sectional shape extending in the axial direction in communication with the tapered hole 14 is formed. The collecting hole 13 is formed to have the same diameter as the introducing hole 11 and is in communication with the introducing hole 11 via the four supply passages 12 as shown in FIG. 4 (b). Each supply passage 12 is formed in a circular cross-section, and extends in the axial direction between the introduction hole 11 and the collecting hole 13. The four supply passages 12 are formed at an interval of 90 ° in the circumferential direction, as shown in FIG. 4 (a).

  As a result, the high-viscosity material P supplied to the introduction hole 11 passes through the four supply passages 12 and gathers in the collecting hole 13 and then reaches the tapered hole 14. Therefore, in the present embodiment, the introduction holes 11, the four supply passages 12 and the collection holes 13 correspond to the “supply holes” supplied with the high-viscosity material P and communicated with the tapered holes 14 as in the present invention. Equivalent to.

  Further, on the proximal end side of the collecting hole 13, a fitting hole 15 having a circular cross-section extending in the axial direction on the inner side in the radial direction of the four supply passages 12 is formed. Further, on the proximal end side of the fitting hole 15, a screw hole 16 extending in the axial direction inward of the four supply passages 12 in the radial direction is formed.

  On the proximal end side of the screw hole 16, an air collecting portion 17 having a circular cross section extending in the axial direction is formed at the center of the body 10 in the radial direction. Furthermore, in the body 10, an air hole 18 having a circular cross section extending radially outward (direction perpendicular to the axis) from the air collecting portion 17 formed at the center is formed penetrating. The air holes 18 are formed at intervals of 90 ° in the circumferential direction so as not to intersect the four supply passages 12. In other words, in the body 10, four supply passages 12 extending in the axial direction and air holes 18 extending in the direction perpendicular to the axial direction are alternately formed at intervals of 45 ° in the circumferential direction. Thus, by providing the air holes 18, the outside air is introduced into the air collecting portion 17.

  FIG. 5 is a view schematically showing the chip 20, and FIG. 5 (a) is a cross-sectional view of the chip 20, and FIG. 5 (b) is a view of the chip 20 viewed from the tip side. The tip 20 is made of metal, and is composed of a circular cylindrical base end 21 and a truncated conical cylindrical tip 23 and has a cylindrical shape as a whole. The proximal end portion 21 is formed with a screw hole 22 having a circular cross section extending in the axial direction. Further, the base end portion 21 is formed so that its outer peripheral surface 21 a is circular, and is fitted into the fitting hole 15 of the body 10. On the other hand, the tip end portion 23 is formed with a tapered hole 24 having a circular cross section extending in the axial direction. Further, the distal end portion 23 is formed as an inclined surface in which the outer peripheral surface 23 a is inclined at the same angle as the tapered surface 14 a of the tapered hole 14 of the body 10.

  In the tip 20, the base end 21 is fitted in the fitting hole 15 and is fixed to the body 10 with a flathead screw 30 so that the outer peripheral surface 23a of the tip 23 faces the tapered surface 14a of the tapered hole 14. To the tip of the body 10. That is, while the proximal end portion 21 is formed to fit into the fitting hole 15, the distal end portion 23 has the outer peripheral surface 23a and the tapered surface 14a in a state where the tip 20 is assembled to the body 10. And so as to form a gap (slit) therebetween.

  FIG. 6 is a view schematically showing a flat head screw 30. As shown in FIG. In FIG. 6, only the lower half of the flat head screw 30 is shown in cross section. The countersunk screw 30 is made of metal, and has a screw portion 31 screwed into the screw hole 22 of the tip 20 and the screw hole 16 of the body 10 and a plate shape (a truncated cone shape) fitted into the tapered hole 24 of the chip 20 And the head portion 32 of As shown in FIG. 6, the countersunk screw 30 is formed with a through hole 33 which extends in the axial direction and penetrates the countersunk screw 30 over the entire length thereof.

  In the coating nozzle 1, after the proximal end 21 of the tip 20 is fitted in the fitting hole 15 of the body 10, the head portion 32 of the flathead screw 30 is fitted in the tapered hole 24 of the tip 20. The screw portion 31 is screwed into the screw hole 22 of the tip 20 and the screw hole 16 of the body 10, and the tip 20 is assembled to the tip of the body 10. With such a configuration, an annular slit having an annular cross section that constitutes the discharge portion 3 for discharging the high viscosity material P is formed between the tapered surface 14 a of the tapered hole 14 and the outer peripheral surface 23 a of the distal end portion 23. Further, the tip end of the screw portion 31 screwed into the screw hole 22 of the tip 20 and the screw hole 16 of the body 10 faces the air collecting portion 17 of the body 10, whereby the countersunk screw 30 is made through the air collecting portion 17. The through hole 33 and the air hole 18 of the body 10 communicate with each other. Therefore, in the present embodiment, the tip 20 and the flathead screw 30 are provided in the nozzle main body (body 10) as in the present invention, have the through holes 33, and the outer peripheral surface of the tip 23 It corresponds to a "tubular member" which is inclined so as to face the tapered surface 14a of the tapered hole 14 at 23a.

  The width W (see FIG. 2) of the slits constituting the discharge unit 3 is preferably 0.3 (mm) or more in order to discharge the high viscosity material P without clogging or the like. Further, since the high viscosity material P has the property of converging to the center due to its own surface tension, the inner diameter ID of the slit (see FIG. 2), in other words, the tip of the tip 20, in order to suppress narrowing due to such surface tension. As for diameter of 4.0, it is preferred that it is 4.0 (mm)-7.0 (mm), and, as for inclination angle theta (refer to Drawing 1) of taper side 14a, 20 degrees-45 degrees are preferred. Furthermore, in this case, the inner diameter of the air hole 18 is preferably 0.5 (mm) to 2.0 (mm).

-Action of coating nozzle-
Next, the operation of the coating nozzle 1 will be described, but prior to that, the problems of the conventional coating nozzle 101 will be described.

  FIG. 8 is a view schematically illustrating a discharge pattern of the conventional coating nozzle 101 and a coating path when the corner portion 50a is coated. The conventional coating nozzle 101 that discharges the high-viscosity material P from the discharge portion 103 formed of a linear slit has directivity, so if coating is performed while moving the coating nozzle 101 in the direction orthogonal to the discharge portion 103, As shown in FIG. 8A, the high-viscosity material P corresponding to the length of the discharge unit 103 is discharged, but when the coating nozzle 101 is moved in a direction parallel to the discharge unit 103, the drawing is performed. As shown in 8 (b), the high viscosity material P is discharged only for the width of the discharge part 103. Therefore, when coating is performed in a track that bends at a right angle (or an acute angle) such as the corner 50a of the work 50, for example, it is conceivable to change the direction of the coating nozzle 101 itself at the corner 50a. There is a problem that the coating thickness becomes thick at 50a, and in particular, when coating is performed from the lower side, liquid dripping occurs at a portion where the coating thickness becomes thick, and the portion where the liquid sag occurs is easily solidified and peeled off There is a problem of becoming

  Therefore, for example, when coating is performed in a track bent at a right angle, the coating nozzle 101 that performs coating while moving in the direction (X direction) orthogonal to the discharge unit 103 is indicated by a dashed arrow in FIG. Then, after moving in the X direction to the outside of the work 50 as it is, direction change is performed outside the work 50 so that the direction orthogonal to the discharge unit 103 coincides with the Y direction perpendicular to the X direction. In many cases, coating is performed while moving the coating nozzle 101 in the direction (Y direction). However, since such a method involves movement operation and movement time outside the workpiece 50, the problem that the operation efficiency of the robot arm is poor, and because the corner portion 50a is coated twice and the coating thickness becomes thick, There is a problem that the above-mentioned dripping of the liquid and peeling resulting therefrom occur.

  For this reason, for example, when coating is performed in a track bent at a right angle (or an acute angle), coating with a non-directive discharge pattern, specifically, as in the present embodiment, the high viscosity material P is used. It is conceivable to employ a coating nozzle that discharges in the form of a truncated cone. However, when the high-viscosity material P is discharged in the form of a truncated cone, it is divided by the coated surface (upper surface) of the work 50, the high-viscosity material P (side surface) in the curtain shape, and the tip (lower surface) of the coating nozzle. Since the closed cone-like closed space is formed, the curtain-like high-viscosity material P has a flow velocity, so a negative pressure region is generated in the closed space, and the high-viscosity material P is drawn into the closed space. And there is a problem that the discharge pattern is not stable.

  Therefore, in the present embodiment, as described above, the high-viscosity material P is discharged in the form of a truncated cone from the discharge portion 3 configured by the slit having an annular cross section, thereby performing coating with a non-directional discharge pattern. A closed space S (see FIG. 1) defined by the surface to be coated of the work 50, the high viscosity material P in a curtain shape, and the tip of the coating nozzle 1 (see FIG. 1) It is in communication with the outside air through the hole 18.

  More specifically, as shown by the white arrow in FIG. 1, the high-viscosity material P supplied to the introduction hole 11 of the body 10 is branched into four supply passages 12 and flows to the tip side, and collects in the collecting hole 13. , Taper hole 14. The high-viscosity material P that has reached the tapered hole 14 is discharged through a slit (discharge part 3) having an annular cross section formed between the tapered surface 14a of the tapered hole 14 and the outer peripheral surface 23a of the tip 23 of the tip 20. Be done. The high-viscosity material P discharged from the discharge part 3 is expanded in diameter as it approaches the work 50 (away from the coating nozzle 1) according to the inclination angle θ of the tapered surface 14a (and the outer peripheral surface 23a) while maintaining the annular shape. As shown in FIG. 1, it is sprayed onto the surface to be painted of the work 50 while forming a truncated cone shape.

  FIG. 7 is a view schematically illustrating a discharge pattern of the coating nozzle 1 and a coating path when the corner portion 50a is coated. As shown in FIG. 7 (a), the coating nozzle 1 is bent at a right angle or an acute angle because the high viscosity material P is sprayed in a non-directive discharge pattern in a curtain shape (cone shape) of a truncated cone. Even when coating is performed on the track, it is not necessary to change the direction of the coating nozzle 1 itself. Therefore, as shown by the broken line arrow in FIG. 7 (b), the coating can be performed with the minimum operation without causing the robot arm or the like to perform unnecessary operation or coating twice. , Can improve the painting efficiency.

  Further, as described above, when the high-viscosity material P is sprayed in the shape of a curtain of a truncated cone, a negative pressure region is generated in the closed space S and it becomes difficult to stabilize the discharge pattern. Since the air hole 18 formed in the body 10 and the through hole 33 of the flathead screw 30 whose tip end faces the closed space S communicate with each other through the air collecting portion 17, the internal pressure and the external pressure of the closed space S Can reduce the pressure difference between the Therefore, the curtain-like high viscosity material P can be prevented from being drawn into the closed space S and disturbed, and the discharge pattern when spraying the high viscosity material P can be stabilized.

(Other embodiments)
The present invention is not limited to the embodiments, and can be implemented in other various forms without departing from the spirit or main features thereof.

  In the above embodiment, the tip 20 and the flat head screw 30 are separately provided. However, the present invention is not limited to this, and may be a cylindrical member in which the tip 20 and the flat head screw 30 are integrally formed.

  In the above embodiment, the body 10, the tip 20, and the flat head screw 30 are separately provided. However, the present invention is not limited to this. The coating nozzle 1 may have the body 10, the tip 20 and the flat head screw 30 integrally formed. .

  Furthermore, in the above embodiment, although the outer peripheral surface 23a of the tip end portion 23 of the tip 20 is an inclined surface inclined at the same angle as the tapered surface 14a of the tapered hole 14 of the body 10, the outer peripheral surface 23a of the tip end portion 23 is If it forms a slit which is inclined so as to face the tapered surface 14a of the tapered hole 14 and discharges the high-viscosity material P in a curtain shape of a truncated cone together with the tapered surface 14a, the present invention is not limited thereto. And the inclination angle θ of the tapered surface 14a may be slightly different.

  Thus, the embodiments described above are merely illustrative in every respect and should not be construed as limiting. Furthermore, all variations and modifications that fall within the equivalent scope of the claims fall within the scope of the present invention.

  According to the present invention, even when coating is performed on a curved track, coating can be performed efficiently with a stable discharge pattern, so it is extremely useful to apply the supplied high-viscosity material to a coating nozzle that discharges from the discharge part. It is.

1 application nozzle 3 discharge part 10 body (nozzle main part)
11 Introduction hole (supply hole)
12 Supply passage (supply hole)
13 Collection hole (supply hole)
14 taper hole 14a taper surface 18 air hole 20 tip (cylindrical member)
23 tip portion 23a outer peripheral surface 30 countersunk screw (cylindrical member)
33 Through Hole P High Viscosity Material

Claims (1)

An application nozzle for discharging the supplied high viscosity material from the discharge unit,
A nozzle main body including a supply hole to which the high-viscosity material is supplied, a tapered hole which is in communication with the supply hole and whose diameter increases toward the tip, and an air hole for introducing outside air;
And a cylindrical member provided in the nozzle body, having a through hole, and inclining so that the outer peripheral surface of the tip end faces the tapered surface of the tapered hole,
The discharge portion is constituted by a slit having an annular cross section formed between the tapered surface of the tapered hole and the outer peripheral surface of the cylindrical member, and the air hole and the through hole communicate with each other. An application nozzle characterized by

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