JP2011088105A - Coating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating apparatus which does not require a large amount of coatings thrown away and which is easily installable in a coating booth. <P>SOLUTION: The coating apparatus 100 includes: an air motor 5 driven by feed of the air and operating pumps 6a, 6b feeding coatings; and an on-off control valve 10, having an operation port 11 communicating with an air source 1, a supply port 12 communicating with an air discharge hole of a coating gun 30, an output port 13 communicate with the air motor 5, and an exhaust port 28 communicating with the atmosphere. When the air discharge hole is closed, the air motor 5 is opened to the atmosphere by making the output port 13 communicate with the exhaust port 28, and when the air discharge hole is opened by operation of a trigger, the output port 13 is made to communicate with the operation port 11 at a predetermined time after start of the air flow to the supply port 12 from the operation port 11. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a painting apparatus used for a painting line of an automobile.

  Conventionally, as a paint gun for coating resin products such as automobile bodies and bumpers, for example, a bell-type paint gun that rotates a cup or disk to atomize paint and spray it on the object to be coated, and pressure is applied to the paint, A spray-type paint gun that mixes air with this to form a paint spray.

  When painting with such a paint gun, if the paint gun trigger is on, the paint tank supply pump is activated, the supply control valve is opened, and the paint line is opened by the valve connected to the trigger. Then, the regulated paint is blown out from the tip of the painting gun. At that time, in the bell-type paint gun, the paint is atomized by the rotation of the cup, disk, etc. and then adheres to the object to be coated. In the spray-type paint gun, the paint is atomized by the supplied air. Adhere to the object to be painted. When the paint gun trigger is turned off, the paint tank supply pump is stopped, the supply control valve is closed, and the paint line is closed by the valve element connected to the trigger. At the same time, the rotation of the cup and disk stops in the bell type paint gun, and the air supply to the paint gun stops in the spray type paint gun.

  In such a coating gun, paint that is not atomized, called a so-called spit, may be sprayed at the start of painting. The spit is, for example, gelation of paint remaining at the nozzle tip of the paint gun when the paint supply is stopped. Further, when the coating line is stopped, the pressure remains in the coating line that connects the supply control valve on the supply pump side and the coating gun, and the gelation of the coating is easily promoted by this residual pressure. In this case, the paint is vigorously discharged from the nozzle of the paint gun by the residual pressure when painting is resumed, and the paint tends to adhere to the object to be coated as spits without being atomized. In particular, in the case of a two-component mixed-type paint in which a main agent and a curing agent are kneaded and used, since the curing agent reacts in the coating line and gelation proceeds, spits are likely to occur in combination with the residual pressure.

  Conventionally, to prevent spit adhesion, it has been practiced to clean the nozzle part of the paint gun before painting and then operate the paint gun to throw away a certain amount of paint, but this method is useless. This is not preferable because it consumes paint.

  Patent Document 1 describes a technique for discharging a catalyst remaining in a nozzle portion of a coating gun by a delay device that delays and controls the off timing of atomization air of the coating gun. However, in this technique, it is necessary to separately install a delay device, and it is necessary to install it outside the painting booth from the viewpoint of explosion prevention, and the layout tends to be complicated. Further, since the number of pipes communicating with the spray gun increases, maneuverability of the spray gun during the coating tends to decrease. Furthermore, since the pressurized paint remains in the paint line and this residual paint is easily gelled by the applied pressure, even the technique of Patent Document 1 does not solve the problem of spit generation at the time of resuming painting, but rather discards the paint. It is also conceivable that the paint may come out more than necessary due to the applied pressure in the paint line during spraying.

  On the other hand, in Patent Document 2, a pressure adjusting valve is provided in a paint line between a color change valve and a paint gun, and an on-off valve is provided downstream thereof. The pressure control valve and the on-off valve are shut off at the same time, and the paint line at the trigger position is shut off at a later time to eliminate the residual pressure of the paint in the paint line at the tip of the on-off valve and then use it It is described that the occurrence of spit is sometimes prevented.

JP-A-6-63465 JP-A-6-285404

  However, according to the technique of Patent Document 2, the control circuit of each valve is complicated, the electric circuit is required to synchronize accurately valves. Since explosion-proof electric circuit in view of needs to be installed outside the paint booth, as with the technique of Patent Document 1, the layout of the apparatus tends to be complicated. In addition, since the pressurized paint remains in the paint line between the supply control valve of the color change valve and the on-off valve, and this residual paint is easily gelled by the applied pressure, in Patent Document 2, a spit is formed. In order to remove the paint, a large amount of paint including the paint between the paint guns must be discharged from the pressure-reducing on-off valve.

  The present invention was created to solve the above-described problems, and an object thereof is to provide a coating apparatus that does not require a large amount of paint to be blown away and can be easily installed in a painting booth. It is said.

  In order to solve the above-described problems, the present invention provides a coating gun having an air port and a paint port that opens and closes in conjunction with a trigger, an air source that supplies air to the coating gun, and a paint applied to the coating gun. A paint supply device for supplying an air motor driven by air supply to operate the paint supply device, an operation port communicating with the air source, and an air port of the paint gun A supply port that communicates with the air motor, an output port that communicates with the air motor, and an exhaust port that communicates with the atmosphere, and an open / close control valve configured to always communicate with the operation port and the supply port, When the mouth is closed, the output port communicates with the exhaust port to release the air motor to the atmosphere, and the trigger is operated to open the air inlet. Come, the air from the operating port to the supply port, characterized in that a configuration in which the air motor is driven by the output port from the time of starting the circulation after a predetermined time elapses in communication with the operating ports.

According to this configuration, when the air inlet is opened by the operation of the trigger, the pressurized air of the air source is ejected from the air inlet via the operating port and the supply port in the initial stage, Since the output port is not in communication, the pressurized air from the air source is not supplied to the air motor. Therefore, the paint supply device does not operate, and the paint is discharged from the paint well only with the residual pressure in the paint supply path connecting the paint supply device and the paint gun. That is, a small amount of paint is blown away. Then, after the elapse of a predetermined time, the output port and the operation port communicate with each other, the air motor is driven, and the paint is supplied from the paint supply device to the paint gun.
According to the present invention, by providing an open / close control valve that operates on air rather than electricity, it is possible to easily install a coating system control system that is difficult to install in the past in terms of explosion protection in the painting booth. It is.

  Further, according to the present invention, the opening / closing control valve includes a valve body having a communication flow path that communicates the operation port and the supply port, and a first air that communicates with the operation port on one side across the valve body. A valve housing in which a second air chamber communicating with the supply port is provided on the other side, and the output port and the exhaust port are formed on an inner peripheral surface on which the valve body slides. An annular groove for selectively communicating the output port with the exhaust port and the operation port is formed on the outer peripheral surface of the body and the inner peripheral surface of the valve housing, and the air port is closed. When the valve body is positioned on the operating port side due to the difference in force received from the pressures of the first air chamber and the second air chamber, the output port communicates with the exhaust port, and the trigger is operated. When the air port is opened, the The valve body is moved to the supply port side by pressurized air from the air source, and the output port communicates with the operation port after a predetermined time has elapsed and receives from each pressure of the first air chamber and the second air chamber. The valve body is stopped at a position where forces are balanced.

  According to this configuration, the opening / closing control valve has a simple structure, and the cost of the coating apparatus can be reduced.

  According to the present invention, it is a coating apparatus that does not require a large amount of paint to be blown away and can be easily installed in a painting booth.

It is a block diagram of the configuration of the coating apparatus according to the present invention. It is a sectional side view which shows an example of a coating gun. It is an action side view of an opening-and-closing control valve when a trigger is opened. FIG. 4 is an operational side view of the opening / closing control valve showing a state in which the cylindrical slide valve body is moving from the state of FIG. 3. FIG. 5 is an operational side view of the open / close control valve showing a state in which the cylindrical slide valve body is stopped at a predetermined position from the state of FIG. 4.

  In FIG. 1, a painting apparatus 100 of the present invention includes a painting gun 30, an air source 1 that supplies air to the painting gun 30, a paint supply device (supply pumps 6a and 6b) that supplies paint to the painting gun 30, An air motor 5 that is driven by the supply of air to actuate the paint supply device (supply pumps 6a and 6b), an operation port 11 that communicates with the air source 1, a supply port 12 that communicates with the air port of the coating gun 30, and an air motor And an opening / closing control valve 10 having a configuration in which the operation port 11 and the supply port 12 are always in communication with each other.

  An operating port 11 of the opening / closing control valve 10 is connected to the piping 2 extended from the air source 1, and an air piping 3 extending toward the coating gun 30 is connected to the supply port 12 of the opening / closing control valve 10. ing. An output port 13 of the open / close control valve 10 is connected via an air pipe 4 to an input port of an air motor 5 for operating the supply pumps 6a and 6b for the main agent and the curing agent of the two-component paint. The air motor 5 is driven when air is supplied from the air pipe 4 to operate the supply pumps 6a and 6b. Each base material and a curing agent supply pump 6a, the supply pipe 7a at a constant rate by 6b, is supplied to the mixer 8 through 7b. The two-component paint kneaded by the mixer 8 is supplied to the paint chamber 31 (FIG. 2) of the paint gun 30 through the paint supply path 9.

  As shown in FIG. 2, the coating gun 30 is provided with a valve rod 33 that is moved back and forth by a trigger 32, and a valve body 34 provided at the tip of the valve rod 33 by the back and forth movement of the valve rod 33 is a paint nozzle of the paint chamber 31. 35 abuts on and away from 35. When the trigger 32 is not used, the valve body 34 closes by contacting the paint throat 35 and closes away from the paint throat 35 when the operator grasps the trigger 32 to open the paint throat 35. The valve rod 33 is always urged by a spring member 36 disposed at the rear so that the valve element 34 abuts against the paint throat 35 and closes.

  The air pipe 3 communicates with the atomizing air passage 37 provided in the coating gun 30. An opening / closing valve 38 is provided in the middle of the atomizing air passage 37. This on-off valve 38 is configured to open and close in conjunction with the movement of the trigger 32. Further, a check valve 39 is provided on the downstream side of the on-off valve 38 in the atomization air passage 37. The downstream end side of the atomizing air passage 37 is such that a part of the downstream end faces the paint port 35 formed at the tip of the nozzle unit 40 as an air port 41 a and the remaining downstream end is the front surface of the nozzle unit 40. The air inlet 41b is formed on each facing surface 42a of the pair of nose portions 42 extending so as to be separated from each other as it goes forward.

  As shown in FIG. 3, the open / close control valve 10 includes a cylindrical member 16 and lid members 14 and 15 that close both end openings of the cylindrical member 16 as a valve housing. The operation port 11 and the supply port 12 are provided in the lid members 14 and 15 coaxially with the cylindrical hole 17 of the cylindrical member 16. The cylindrical hole 17 includes a small-diameter hole portion 17a formed on the operating port 11 side and a large-diameter hole portion 17b formed on the supply port 12 side and having a slightly larger diameter than the small-diameter hole portion 17a. The small diameter hole portion 17a is formed longer in the axial direction than the large diameter hole portion 17b.

  In the cylindrical hole 17 of the cylindrical member 16, there is a cylindrical slide valve body 18 having a small diameter cylindrical portion 18a and a large diameter cylindrical portion 18b that slide relative to the inner circumference of each of the small diameter hole portion 17a and the large diameter hole portion 17b. It is arranged. That is, the space of the small-diameter hole 17a (first air chamber that communicates with the operation port 11) on one side across the cylindrical slide valve body 18 and the space of the large-diameter hole 17b (second air that communicates with the supply port 12) on the other side. Chamber) is formed. A small-diameter hole 19 is formed on the axial line in the small-diameter cylindrical portion 18a of the cylindrical slide valve body 18, and one end of the small-diameter hole 19 opens at an end surface 27a of the small-diameter cylindrical portion 18a. The large diameter cylindrical portion 18b has a large diameter hole 20 formed on the axis. One end of the large diameter hole 20 extends into the small diameter cylindrical portion 18a and communicates with the other end of the small diameter hole 19. The other end is opened at the end surface 27b of the large diameter cylindrical portion 18b. That is, the small diameter hole 19 and the large diameter hole 20 constitute a communication flow path that connects the operation port 11 and the supply port 12. Around the one end of the large-diameter hole 20, four air supply holes 21 that are provided at equal intervals in the radial direction and at intervals of 90 degrees in this embodiment are formed to penetrate. And in the outer peripheral surface of the small diameter cylinder part 18a, the annular grooves 22 and 23 are formed in the boundary part of the site | part in which the air supply hole 21 was formed, and the large diameter cylinder part 18b, respectively. That is, each air supply hole 21 is formed in the circumferential bottom surface of the annular groove 22.

  On the other hand, in the state where the cylindrical slide valve body 18 is in contact with the lid member 15, an annular groove 24 facing the annular groove 22, a small-diameter hole portion 17 a, and a large diameter are formed on the inner peripheral surface of the cylindrical hole 17 of the cylindrical member 16. An annular groove 25 opposed to the periphery of the boundary with the diameter hole portion 17b and an annular groove 26 located at a substantially intermediate portion between the annular grooves 24 and 25 are formed. On the inner peripheral surface of the cylindrical member 16, an output port 13 is opened so as to face the annular groove 26, and an exhaust port 28 communicating with the atmosphere is opened so as to face the annular groove 25. Or more annular grooves 22 to 26, the output port 13 to exhaust port 28 functions as a communication passage for communicating either the operating ports 11.

  The operation of the coating apparatus 100 will be described with reference to FIGS. When the coating gun 30 is not used, that is, when the trigger 32 is opened, the valve body 34 closes the paint mouth 35 and the on-off valve 38 disposed in the middle of the atomizing air passage 37 is closed. It has become. Accordingly, the pressure of the air supplied from the pipe 2 to the operation port 11 of the opening / closing control valve 10 is the same as the pressure of the air staying in the air pipe 3 disposed between the coating gun 30 and the supply port 12. In the opening / closing control valve 10, due to the difference in pressure receiving area between the end surfaces 27a and 27b of the small diameter cylindrical portion 18a and the large diameter cylindrical portion 18b, that is, the large diameter end surface 27b exerts a larger force than the small diameter end surface 27a. by receiving, as shown in FIG. 3, a cylindrical slide valve body 18 is in the contact with the end face of the cover member 15. In this state, the annular grooves 25, 23, and 26 communicate with each other, whereby the output port 13 and the exhaust port 28 communicate with each other, and the pressurized air in the air pipe 4 connected to the air motor 5 is released to the atmosphere.

  Next, when the operator grasps the trigger 32 to perform painting, the valve element 34 is opened, and the on-off valve 38 disposed in the middle of the atomizing air passage 37 is also opened. The inside air is ejected from the air inlets 41a and 41b, and the pressure in the air pipe 3 is reduced. Therefore, as shown in FIG. 4, the cylindrical slide valve body 18 moves to the lid member 14 side having the supply port 12 by the pressurized air supplied from the air source 1 to the operation port 11 of the open / close control valve 10. During this time, the pressurized air supplied to the operating port 11 is supplied from the small diameter hole 19 of the cylindrical slide valve body 18 to the supply port 12 through the large diameter hole 20, so that air is ejected from the air ports 41a and 41b. Is maintained, and the paint that has adhered and gelled to the nozzle portion 40 is peeled off.

  Since air is not supplied from the output port 13 to the air motor 5 when the pressurized air is supplied to the supply port 12 and air is ejected from the air ports 41a and 41b, the air from the air ports 41a and 41b is not supplied. For a moment during the initial ejection, that is, while the cylindrical slide valve body 18 moves to the lid member 14 side, the paint is discharged from the paint mouth 35 only with the residual pressure in the paint supply passage 9, and a small amount of paint is thrown away. Done. Therefore, even when the gelled paint is included, the spit is prevented from being generated in the main coating by being blown away.

  Then, as shown in FIG. 5, the cylindrical slide valve body 18 moves to the vicinity of the lid member 14 and stops. This stop position is determined by the force applied to the end surface 27a of the small diameter cylindrical portion 18a by the pressure in the small diameter hole portion 17a generated by the air supply from the operation port 11, and the back pressure of the large diameter hole portion 17b. This is a position where the force applied to the end face 27b is balanced. At this time, the pressurized air from the air source 1 passes through the small-diameter hole portion 17a from the operating port 11, passes through the small-diameter hole 19, the large-diameter hole 20, the air supply hole 21, and the annular groove 22 provided in the cylindrical slide valve body 18. Then, the oil is supplied to the output port 13 through the annular groove 26 and through the small-diameter hole portion 17a from the operation port 11 through the annular groove 24, the annular groove 22 and the annular groove 26 in this order. As a result, the air motor 5 is driven with a slight delay from the time when the operator operates the trigger 32, that is, the air motor 5 is driven after a predetermined time has elapsed since the start of air flow from the operating port 11 to the supply port 12. , feed pumps 6a, base and curing agent by 6b supply pipe 7a to scale, 7b the flow, is supplied to the mixer 8. The two-component paint kneaded by the mixer 8 is supplied to the paint chamber 31 of the paint gun 30 through the paint supply path 9 at a constant pressure, so that the paint pressure in the paint supply path 9 is prevented from being reduced. At the same time, air flows through the operating port 11, the small-diameter hole portion 17b, the annular groove 24, the annular groove 22, the air supply hole 21, the large-diameter hole 20, and the supply port 12 in this order, and air of appropriate pressure is supplied to the air inlet 41a. , 41b, and the paint from the paint spout 35 is sprayed at an appropriate pressure. When the operator releases the trigger 32, the open / close control valve 10 returns to the state shown in FIG.

  Here, the timing from when the operator grasps the trigger 32 until the air motor 5 is driven is a state in which the small-diameter cylindrical portion 18a of the cylindrical slide valve body 18 is in contact with the end portion of the lid member 15 having the operation port 11. To the state in which the end of the small diameter cylindrical portion 18a is located in the annular groove 24 and the annular groove 22 of the small diameter cylindrical portion 18a and the annular groove 26 of the cylindrical member 16 communicate with each other. The timing can be easily changed by adjusting the relationship.

  Thus, by providing the opening / closing control valve 10 that is operated by air so as to be able to control the timing of paint atomization air and paint supply, the apparatus can be simplified and the cost of the apparatus can be reduced. In addition, since the open / close control valve 10 that operates with air without using electrical control is used as the control system, the control system of the coating apparatus 100 that is difficult to install in terms of explosion prevention is easily installed in the coating booth 200. It becomes possible to do. Therefore, the piping system is shortened and the time lag is suppressed, and also from this point, the amount of paint discarded as a spit countermeasure is reduced.

1 Air source 5 Air motor 6a, 6b Supply pump (paint supply device)
10 Open / Close Control Valve 11 Operating Port 12 Supply Port 13 Output Ports 14 and 15 Lid Member (Valve Housing)
16 Cylindrical member (valve housing)
17a Small hole (first air chamber)
17b Large-diameter hole (second air chamber)
18 Cylindrical slide valve (valve)
19 Small-diameter hole (communication flow path)
20 Large-diameter hole (communication flow path)
22-26 annular groove 28 exhaust port 30 coating gun 32 trigger 35 paint port 41a, 41b air port 100 coating device 200 coating booth

Claims (2)

A paint gun with an air port and paint port that opens and closes in conjunction with the trigger;
An air source for supplying air to the paint gun;
A paint supply device for supplying paint to the paint gun;
A coating apparatus comprising:
An air motor that is driven by the supply of air and operates the paint supply device;
An operation port that communicates with the air source, a supply port that communicates with an air port of the paint gun, an output port that communicates with the air motor, and an exhaust port that communicates with the atmosphere. The operation port and the supply port are always An open / close control valve having a communication configuration;
When the air port is closed, the output port communicates with the exhaust port, whereby the air motor is opened to the atmosphere.
When the air port is opened by the operation of the trigger, the output port communicates with the operation port after a predetermined time has elapsed from the time when air starts to flow from the operation port to the supply port. A painting apparatus characterized by being configured to drive. The opening / closing control valve is
A valve body that forms a communication channel that communicates the operating port and the supply port;
A first air chamber that communicates with the operation port on one side of the valve body and a second air chamber that communicates with the supply port are provided on the other side, and the output port and the inner peripheral surface on which the valve body slides are provided. A valve housing in which the exhaust port is formed;
An annular groove for selectively communicating the output port with the exhaust port and the operation port is formed on the outer peripheral surface of the valve body and the inner peripheral surface of the valve housing,
When the air port is closed, the valve element is positioned on the operation port side due to a difference in force received from each pressure of the first air chamber and the second air chamber, and the output port is the exhaust port. Communicate with
When the air port is opened by the operation of the trigger, the valve body is moved to the supply port side by pressurized air from the air source, and the output port communicates with the operation port after a predetermined time has elapsed. The coating device according to claim 1, wherein the valve body stops at a position where the forces received from the pressures of the first air chamber and the second air chamber are balanced.

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