JPH022457Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a liquid applicator that can prevent liquid such as a sealant (hereinafter referred to as a sealant) from dripping.

[Prior art]

Generally, a liquid applicator is a device that applies sealant to a workpiece from an application nozzle while moving the gun body along the application line of the workpiece.
Conventionally, in this liquid application device, even if the supply of sealant to the application nozzle is stopped at the end of application of the sealant, a small amount of the sealant flows out from the application nozzle, which is a so-called problem of sealant dripping. It was hot.

Therefore, in order to solve the above-mentioned problem of dripping, the applicant installed a device in the discharge pipe made of an elastic material to expand the internal volume of the pipe, and when coating is finished, the applicant expands the internal volume of the pipe to apply the coating. An application has been filed regarding a liquid applicator that draws a sealant at the tip of a nozzle into the nozzle (see Japanese Utility Model Application Publication No. 57-204074).

However, in the conventional device, even if the internal volume of the discharge pipe is expanded by the internal volume expansion device, since the discharge pipe is an elastic body, the discharge pipe is likely to contract by the increased internal volume. As a result, the sealant was not so much sucked in, and in the end, the effect of preventing dripping by the conventional device was not very high.

[Purpose of invention]

The present invention was developed in this conventional situation, and it is an object of the present invention to provide a liquid applicator that can reliably prevent the sealant from dripping.

[Structure of the idea]

In a liquid applicator, a nozzle cylinder having a piston that fits into the inner pipe is attached to the inner pipe connected to the discharge side of the gun body, and an outer nozzle having a coating hole at the tip is integrated with the piston of the nozzle cylinder. A switching valve is provided for moving the outer nozzle forward by using the nozzle cinder when the gun body is moved backward by the gun body longitudinally moving cylinder. The product is expanded to eliminate the effects of deformation of the pipe.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The drawing shows a liquid applicator according to an embodiment of the present invention. In the drawing, 1 is a gun body, and a sealant introduction pipe is connected to a sealant inlet (not shown) of this gun body. is sealant 1
0 is supplied through the sealant introduction pipe. The gun body 1 also has the supplied sealant 1.
An on-off valve 2 is formed for supplying and shutting off the supply of 0 to the workpiece coating surface, and this on-off valve 2 is fixed to the tip of a bubble stem 2a, and a ball 2b that contacts a valve seat 1b moves it from side to side as shown in the figure. It consists of a drive device.

A connecting flange 3a of the inner pipe 3 is fixed to the connecting recess 1c of the gun body 1 by a connecting nut 1d, so that the inner pipe 3 communicates with the sealant discharge port 1a of the gun body 1.

Further, a nozzle cylinder 4 concentric with the inner pipe 3 is fitted, and the nozzle cylinder 4
A mounting bracket 4a having a vertical cross section is fixed to the mounting bracket 4a, and the bracket 4a is connected to the connecting flange portion 3 of the inner pipe 3 by means of a set bolt 4b.
It is installed near a. A piston 5 is slidably inserted into the nozzle cylinder 4, and a base 5a of the piston 5 is slidably fitted into the inner pipe 3.
A tubular outer nozzle 5b is provided at the tip of the base 5.
a, and the outer nozzle 5
An application hole 5c for applying the sealant 10 to the workpiece is formed at the tip of b. In addition, 8a~
8c is a sealing member for sealing between each movable part.

Reference numeral 6 denotes a gun body back-and-forth movement cylinder for moving the gun body 1 forward and backward, and this is fixed to the pedestal of the device of this embodiment, and the piston rod 6a of the cylinder 6 is connected to the gun body 1 by a connecting bar 6b. has been done.

7 is a high-pressure air supply device that supplies high-pressure air to the gun body longitudinally movable cylinder 6 and the nozzle cylinder 4; 7b is a switching valve that directs the high-pressure air from the air source 7a to the extension side of the nozzle cylinder 4; Alternatively, the supply is switched to the contraction side, and the supply is switched to the extension side or the contraction side of the gun body longitudinally movable cylinder 6. 7c and 7d are nozzle cylinders 4, respectively.
high-pressure air supply passage, gun body longitudinal movement cylinder 6
This is a high-pressure air supply passage.

Next, the operation will be explained.

When the application of the sealant starts, the switching valve 7b is in the opposite state as shown in the figure, so that high-pressure air flows to the contracting side of the gun body longitudinally moving cylinder 6 and the nozzle cylinder 4.
The gun body 1 is in its forward position together with the nozzle cylinder 4, and the outer nozzle 5b is in its retracted position together with the piston 5.

To start applying the sealant, the ball 2b is moved backward by the driving device of the on-off valve 2, and in this state the gun body 1 is moved so that the outer nozzle 5b follows the application line of the workpiece. Then, the sealant 10 passes through the inner pipe 3 and is applied to the workpiece application surface from the application hole 5c of the outer nozzle 5b.

When the application of the sealant 10 is completed, the ball 2b of the on-off valve 2 moves forward and comes into contact with the valve seat 1b, thereby stopping the supply of the sealant 10 to the inner pipe 3 and outer nozzle 5b.
Then, when the supply of sealant is stopped, the switching valve 7
b is switched to the illustrated state, whereby high-pressure air is supplied to the extension side of the gun body longitudinal movement cylinder 6, and the gun body 1 is moved backward. Also, at the same time,
High-pressure air is also supplied to the extension side of the nozzle cylinder 4, causing the outer nozzle 5b to move forward, thereby expanding the volume of the area surrounded by the outer nozzle 5b and the tip of the inner pipe 3, and creating a negative pressure in the area. As a result, the sealant 10a near the application hole 5c of the outer nozzle 5b is drawn into the position shown by the two-dot chain line in the figure.

In this way, in this embodiment, when the application of the sealant 10 is completed, the opening/closing valve 2 is closed and the outer nozzle 5b is moved forward, so that it is not affected by the deformation of the elastic discharge pipe as in the conventional case. Therefore, the internal volume near the application hole 5c of the outer nozzle 5b can be reliably expanded, and the sealant 10 can be drawn into the outer nozzle 5b to reliably prevent the sealant 10 from dripping. Furthermore, since the entire apparatus of this embodiment is moved backward in conjunction with the forward movement of the outer nozzle 5b, the outer nozzle 5b does not come into contact with the workpiece.

[Effect of idea]

As described above, according to the liquid applicator according to the present invention, when the application of the sealant is finished, the entire apparatus is moved backwards and the outer nozzle is moved back and forth to expand the internal volume of the nozzle. This has the effect of reliably drawing the sealant into the nozzle and reliably preventing the sealant from dripping.

[Brief explanation of the drawing]

The drawing is a schematic diagram of a liquid coating device according to an embodiment of the present invention. 1... Gun body, 1a... Discharge port, 2... Open/close valve, 3... Inner pipe, 4... Nozzle cylinder, 5... Piston, 5b... Outer nozzle, 5c... Application hole, 6... Gun Main body longitudinally moving cylinder, 7b...Switching valve.

Claims (1)

[Scope of utility model registration request] A device for applying a liquid such as a sealant to a workpiece, which includes a gun body that is supplied with the liquid and is provided with an on-off valve for supplying and shutting off the liquid to the workpiece coating surface, and a gun body on the discharge side of the gun body. A nozzle cylinder having a connected inner pipe, a piston provided concentrically around the inner pipe and slidably fitted to the inner pipe, and a nozzle cylinder provided integrally with the piston of the nozzle cylinder and having a liquid at its tip. an outer nozzle having a coating hole; a gun body back-and-forth movement cylinder that moves the gun body forward and backward; and a gun body back-and-forth movement cylinder that moves the gun body when the on-off valve of the gun body is closed and the gun body back and forth movement cylinder moves the gun body backward. A liquid application device comprising: a switching valve for moving an outer nozzle forward;