JPH04265171A - Coating gun - Google Patents

Abstract

PURPOSE:To offer such a coating gun having a characteristic feature in the cleaning function of a nozzle part for spraying a coating material to a body to be coated. CONSTITUTION:A valve chamber 6 and an entrance of coating material supply path in the gun main body 1 are freely opened and closed with a valve rod 8 which can freely move back and forth so that the entrance is opened to allow the coating material to flow and is closed to cut the supply of the coating material. When the entrance is closed, a detergent introducing hole 9 provided on the valve rod 8 is connected to the entrance of the coating material supply path so that a cleaning circuit 4 is formed. On the other hand, a nozzle part 2 of the top of the main body is equipped with a sealing type orifice member which can be inversed in the housing and has a through hole inside. The both ends of this hole are provided with orifice spraying holes 25, 26. When the detergent is made to flow, the orifice member 22 is inversed and the detergent is introduced from the orifice spraying holes 25, 26 which have been used to spray the coating material till the time. Thereby, the cleaning effect can be increased.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating gun that sprays paint onto an object to be coated, and which has a nozzle cleaning function.

0002

2. Description of the Related Art Conventionally, there has been known a device for detecting clogging of a nozzle opening in a painting gun that sprays paint from a nozzle portion to perform painting. Such a device, as shown in Utility Model Application Publication No. 63-58661, for example, uses a detection means installed near the nozzle injection hole to detect the collapse of the spray pattern shape during paint spraying, and detects the nozzle opening. When a blockage occurs, the system uses the change in the spray pattern to issue an alarm. Also, as a similar type of clogging detection device, there is a method disclosed in Japanese Utility Model Application No. 63-144868 or Japanese Utility Model Application No. 1
A device such as No.-120958 has also been disclosed.
On the other hand, there is also known a device for cleaning the interior of such a coating gun when it becomes clogged. For example, Utility Model Hei 2-866
In the case of No. 66, thinner and air are alternately introduced into the paint gun to remove paint remaining inside the hose and the like.

0003

[Problem to be Solved by the Invention] However, in the conventional case, even if a clog is detected by a clog detection device, if the clog is in a constricted area such as a nozzle, the nozzle is disassembled and cleaned. The problem was that it was necessary and time-consuming. That is, as in the above-mentioned Utility Model Application Publication No. 2-86666,
Even if cleaning liquid and air are introduced, if the cleaning liquid, etc. is flowed in the same direction as the paint discharge direction, it cannot be removed effectively, especially in places with narrow passages, so it is necessary to remove the nozzle part for cleaning in order to increase the cleaning effect. It is necessary to do so.

0004

[Means for Solving the Problems] In order to solve the above problems, the present invention allows the valve chamber inside the gun body and the inlet of the paint supply path to be opened and closed by a valve member, and the paint and the cleaning liquid can be selected by the valve member. It was designed to supply the liquid to the tip nozzle section. This nozzle portion was provided with a liquid-tight orifice member that was reversible within the housing, and a pair of orifice injection holes were provided at both ends of a through hole that penetrated the inside of this orifice member. Each orifice injection hole was arranged to face the outlet of the paint supply path. In addition, the valve member is provided with a cleaning passage hole that communicates with the cleaning circuit, and is made to be able to slide back and forth by a driving means, retreating to open the valve chamber and the inlet of the paint supply path, and moving forward to open the valve chamber and the paint supply path. The inlet of the supply path is shut off, and the cleaning liquid passage hole and the inlet of the paint supply path are communicated with each other.

[0005]

[Operation] The paint introduced into the valve chamber inside the gun body is supplied to the nozzle section through the paint supply path, but by closing the entrance of this paint supply path with the valve member, the supply of paint is interrupted.
A circuit that supplies cleaning liquid to the nozzle section is configured. By making the nozzle part and orifice member reversible, the cleaning liquid can be introduced from the orifice nozzle on the opposite side from when spraying paint, which is opposite to the paint flow direction, increasing cleaning efficiency. . Therefore, the trouble of disassembly etc. can be saved.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the coating gun of the present invention will be explained based on the attached drawings. Figure 1 is an overall view of the painting gun of the present invention, Figure 2 is an enlarged view of the gun body and nozzle section, and Figure 3 is Figure 2.
FIG. 4 is a cross-sectional view taken along line A-A of FIG. 3, as seen from direction B in FIG. As shown in Figure 1, the painting gun of the present invention includes a gun body (1) that can be attached to the tip of a robot, a nozzle part (2) that is attached to the tip of the gun body (1), and a paint gun that supplies paint. Paint circuit (3) for cleaning and cleaning circuit (3) for cleaning
4), and is configured to automatically perform tasks from painting to cleaning.

As shown in FIG. 2, the gun body (1) is equipped with a valve chamber (6) connected to the paint circuit connection port (5), and a valve seat (7) is provided on the front side of this valve chamber (6). is attached, and a valve stem (8) serving as a valve member is slidably fitted into the opening on the rear side of the valve chamber (6) and runs longitudinally through the valve chamber (6). The valve stem (8) is provided with a cleaning liquid passage hole (9), which will be described later, and a cylinder unit (not shown) is disposed on the rear end side of the valve stem (8). ) is said to be able to move forward and backward. Also, a paint supply channel (10) is bored in the center of the aforementioned valve seat (7),
The tip of the valve stem (8) can freely come into contact with the inlet of the paint supply path (10) on the valve chamber (6) side.

On the other hand, a cleaning circuit connection port (11) is provided on the rear side of the valve chamber (6). A space (12) in the center of the main body that communicates with this cleaning circuit connection port (11)
) are provided with sealing members (13) (13) at the front and rear,
They are each pressed in the direction of separation by an elastic member (14). This central space (12) is kept liquid-tight. In addition, the cleaning liquid passage hole (9) of the valve stem (8) mentioned above is
When the valve stem (8) is moved forward, the opening on the rear side faces into this space (12), and the opening at the tip of the valve stem (8) on the front side faces into the paint supply path (10).

Next, the nozzle portion (2) includes a nut member (16) that is screwed onto the tip of the main body (1).
A pattern detection member (18) is screwed onto the outer periphery of the air nozzle member (17) that engages with the tip of the air nozzle member (17). A housing member (19) is attached to the inner peripheral surface of the air nozzle member (17), and the rear end side of this housing member (19) is attached to the front end surface of the aforementioned valve seat (7). It is in close contact with the packing member (20). The center of this packing member (20) also has a paint supply path (
20a) is provided. A substantially spherical orifice member (22) is provided in the internal space (21) of the housing member (19).
) is provided. This orifice member (22) is
The housing member (19) is provided in a liquid-tight manner with respect to the inner surface thereof, and includes two orifice injection holes (25) and (26) that communicate with each other through an internal through hole (24).

By the way, this orifice member (22) is constructed so that it can be reversed by 180 degrees. That is, as shown in FIG. 3, a shaft member (27) is attached to this orifice member (22).
7) includes a housing member (19) and an air nozzle member (1).
7), the pattern detection members (18) are rotatably penetrated and extended to the outside, and a gear member (28) is attached to the extending end.
is installed. A chain belt (29) is wound around this gear member (28) and connected to a drive source (not shown). For this reason, the rotational driving force is transferred to the chain belt (
29) to the gear member (28), the orifice member (22) rotates together with the shaft member (27) about the shaft. and two orifice nozzles (25), (
26) can face the front of the outlet of the paint supply path (20a).

Next, the configuration of the air supply system for shaping the spray pattern of paint during paint spraying and the detection means for detecting pattern collapse will be explained. As shown in FIGS. 1 and 2, the gun body (1) is provided with an air connection port (31), and the air connection port (31) is connected to an air source (33) via an on-off valve (32). ) is connected, and the gun body (
It communicates with the air chamber (35) of the nozzle part (2) through the air passage hole (34) provided in the nozzle part (2). Further, the air nozzle member (17) described above is provided with an air passage hole (36) that communicates with this air chamber (35).
) passes through the bent portions (17a) projecting inward from both sides in front of the air nozzle member (17), and exposes the jet port (37) in front of the orifice member (22).

The pattern detection member (18) attached to the outside of the air nozzle member (17) also has bent portions (18a) projecting inward from both sides of the front.
are provided, and the ends of the optical cables (38) face each other in pairs to the pair of bent portions (18a) (18a). And optical cable (38
) is equipped with a floodlight (39
), and a light receiver (40) is provided on the other side, which is connected to an amplifier (41) for amplifying the received light signal. Based on this signal, the reversal of the orifice member (22) and the operation of the cleaning circuit, which will be described later, are automatically controlled.

Next, the paint circuit (3) and cleaning circuit (4) will be explained. The paint circuit (3) is equipped with a plurality of paint sources (43), thinner sources (44), and air sources (45) in order to apply various colors. (47). This manifold (47) is connected to the aforementioned paint circuit connection port (5). On the other hand, the cleaning circuit (4) includes a thinner source (49) and an air source (50) for cleaning, and is controllable by respective on-off valves (51) and (52), as well as a check valve ( 53) to the cleaning circuit connection port (1
1). And this on-off valve (51), (
The opening/closing valve (52) is configured to automatically control opening/closing based on the detection result by the above-mentioned pattern detecting means.
51) and (52) are activated.

The operation of the coating gun constructed as above is as follows. When painting by spraying paint, the valve stem (8) of the gun body (1) is in the retracted position, and the valve chamber (
6) and the inlet of the paint supply path (10) are open and communicate with each other. Therefore, the paint supplied from the paint circuit (3) enters the internal space (21) from the valve chamber (6) through the paint supply path (10) (20a), and enters the orifice on one side of the orifice member (22). It is injected from the nozzle hole (26) through the through hole (24) and from the orifice nozzle hole (25) on the other side. At this time, since the orifice injection hole (25) has a vertically elongated flat circular shape as shown in FIG. 4, the ink is ejected while expanding in a vertically elongated fan shape. Also, at the same time, the air source (
Air supplied from the air nozzle member (17)
It is ejected from the nozzle (37) at the tip, and this fan-shaped ejection pattern is further shaped into a flat one.

The optical cable (38) of the pattern detection member (18) detects an abnormality in this injection pattern. In other words, if the pattern is normal as shown in Figure 3, the optical path between the pair of optical cables (38) and (38) will be blocked by the spray droplets and no light will be received, but the normal pattern will be disrupted. Then, one of the optical cables (38) becomes conductive and an abnormality is detected. Such a break in the spray pattern is often caused by paint scum or foreign matter adhering to the vicinity of the orifice injection hole (25) of the orifice member (22).

[0016] When an abnormality is detected, the painting operation is interrupted and the cleaning circuit is activated. That is, once the main body (1) is separated from the object to be coated, the valve stem (8) moves forward to cut off the gap between the valve chamber (6) and the paint supply path (10), and instead the inside of the valve stem (8) The cleaning liquid passage hole (9) and the paint supply path (10) are communicated with each other. At the same time, the orifice member (2
2) is reversed 180 degrees. For this reason, the orifice nozzle (2
5) and (26) are reversed. Next, the cleaning circuit (4
) are alternately supplied with a thinner source (49) and an air source (50) to clean the orifice nozzle (25) and through hole (24) from the paint supply path (10), and clean the other orifice nozzle (26).
) is released to the outside. At this time, the orifice nozzle hole (25), which had been on the discharge downstream side, is now located on the upstream side of the flow path in the cleaning state, and conversely, the orifice nozzle hole (26), which was on the upstream side, is now on the downstream side. Paint scum and foreign matter are effectively removed. After cleaning is completed, the valve stem (8
) moves back and the coating operation resumes.

[0017]

As described above, the coating gun of the present invention activates the cleaning circuit immediately when clogging of the discharge nozzle is detected, and moreover, the orifice member is reversed for cleaning, so that countermeasures can be taken quickly and the paint The flow direction of the cleaning liquid and the flow direction of the cleaning liquid are reversed, so that cleaning with high cleaning efficiency is possible. Further, by configuring switching between paint and cleaning using a valve member, it is possible to simplify and downsize the apparatus.

[Brief explanation of the drawing]

[Figure 1] Overall view of the painting gun

[Figure 2] Enlarged view of the gun body

[Fig. 3] A sectional view taken along the line A-A in Fig. 2, showing the nozzle part.

[Figure 4
]B view of Figure 3

[Explanation of symbols]

1. Gun body,
2. Nozzle part 3. paint circuit,
4. Cleaning circuit 6. Valve chamber, 8
．． Valve stem9. Cleaning liquid passage hole,
10,20a. Paint supply path 22. Orifice member, 24.
Through holes 25, 26. Orifice nozzle.

Claims (2)

[Claims] 1. A painting gun in which a valve chamber and a paint supply passage inlet inside the gun body can be opened and closed by a valve member, and paint and cleaning liquid are selectively supplied to a tip nozzle by the valve member, The nozzle portion includes a liquid-tight orifice member that is reversible within the housing, and this orifice member is provided with a pair of orifice nozzle holes at both ends of a through hole penetrating the inside, and each of these orifice nozzle holes is A painting gun characterized in that the gun body is configured to face and communicate with the paint supply path outlet portion of the gun body. 2. The valve member is provided with a cleaning fluid passage hole that communicates with the cleaning circuit, and is slidable back and forth by a driving means to open the valve chamber and the entrance portion of the paint supply path that are connected to the paint circuit when retracting. 2. The coating gun according to claim 1, wherein the valve chamber and the inlet of the paint supply path are shut off when the gun moves forward, and at the same time, the cleaning liquid passage hole and the inlet of the paint supply path are communicated with each other.