JPH0213104Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cleaning device for a flow path that includes a valve device whose opening degree is adjusted to a certain degree in advance.

For example, in a painting device, a device is equipped with a valve device whose opening degree is adjusted to a certain degree, and a pressure regulating device is used to supply paint adjusted to a constant pressure to this device, and the valve device is opened as necessary for painting. When attaching a cleaning device to a paint supply line, it is a common practice to install a branch line via a switching valve upstream of the paint supply line, and to provide a cleaning liquid supply source upstream of this branch line. Since the opening degree of the valve device is constant and the pressure of the cleaning fluid is also adjusted to a constant pressure by the pressure regulating device, the flow rate is limited to approximately the same level as the flow of paint, which not only takes a long time for cleaning. , there are serious defects that make cleaning uncertain.

In order to deal with the above-mentioned defects, the present invention adopts a pressure reducing valve type controlled by air pressure as a pressure regulating device, and by switching high and low pressure of the control pressurized air supplied to this pressure regulating device,
Even when the opening area of the valve device is small, the pressure of the cleaning liquid can be supplied with almost no restriction in the pressure regulating device, so that a large amount of cleaning liquid can flow through the valve device in a short time. The embodiment shown in the drawings will be described in detail below.

As shown in FIG. 1, for example, the present invention is applicable to a valve device 4 comprising a valve seat 2 at the tip of a valve chamber 1 and a needle valve 3 that opens and closes by advancing and retracting with respect to the valve seat 2.
In addition, a liquid jet nozzle 5 is provided in front of the valve seat 2, and an annular atomizing air nozzle 6 is provided on its outer periphery in a coaxial relationship, and the needle valve 3 connects this to a piston 8 in an air cylinder 7 at the rear. The piston 8 is always kept in a forward direction by the spring 9, and on the other hand, by supplying pressurized air from the pressure air supply source 10 through the on-off switching valve 11 into the cylinder 7, the spring 9 is forced into the piston 8. An air spray gun 13 is provided which is retracted to a position where it is blocked by an opening adjustment stopper 12, and a paint supply source is provided as a facility for supplying pressurized liquid such as paint to this gun 13. 14, a switching valve 15, and a pressure regulating device 16 controlled by pneumatic pressure, so that the paint is constantly supplied at a constant pressure, thereby increasing the pressure to the piston 8 while blowing out atomizing air from the nozzle 6 as necessary. The object of the present invention is a coating apparatus in which a needle valve 3 is opened backward by supplying air, and paint is atomized and sprayed from a nozzle 5 for painting.

For cleaning the coating equipment, a four-way valve is adopted as the switching valve 15, and the cleaning liquid supply source 17 and the exhaust air supply source 18 are connected to the paint supply source 1.
The paint, air, and cleaning liquid from 4 can be selectively supplied by switching the switching valve 15, but if the cleaning liquid is simply supplied in this way,
Not only is the opening degree of the needle valve 3 in the gun 13 limited, but also the pressure on the secondary side is controlled by the pressure regulator 16, so the flow rate of the cleaning liquid is almost the same as in the case of paint spraying, and is small. be.

In particular, the present invention increases the control air pressure for the pressure regulator 16 during cleaning to reduce the degree of pressure reduction by the pressure regulator 16 and significantly increase the secondary pressure. In order to supply control air to the pressure regulating chamber, a high-pressure air supply source 19 of, for example, about 5 kg/cm ² and a low-pressure air supply source 20 of, for example, about 1 kg/cm ² are used.
and both air supply sources 19, 2.
0 with the intervention of the switching valve 21 and the pressure regulator 16
When spraying paint, the paint is pressurized at about 5 kg/cm ² from the paint supply source 14 under the control of low-pressure air from the low-pressure air supply source 20. At 16, the pressure is reduced to, for example, 1 kg/cm ² to maintain a relatively small flow rate.On the other hand, when cleaning, the switching valve 1 is
5 to a pressurized air supply of 5 kg/cm ² from the air supply source 18 or a pressurized cleaning liquid supply of about 5 kg/cm ² from the cleaning liquid supply source 17, and the switching valve 2
1 to the high-pressure air supply source 19, the pressure regulator 16 is set to a high pressure regime close to 5 kg/cm ² on the secondary side, and thereby the gun 1 is connected to the high pressure air supply source 19.
It goes without saying that high-pressure cleaning liquid or air can be supplied to the valve chamber 1 of 3 to perform cleaning work in a short time, and that the needle valve 3 is moved back during cleaning.

The gun 13 is installed using a facility that switches the control air pressure for the pressure regulator 16 into two levels: high and low.
If the needle valve 3 in the gun 13 is moved backward in two steps, the flow rate can be further increased and the cleaning efficiency can be improved. In addition to adopting a relatively weak spring 9 to keep the spring 9 in the same direction, a spring receiving member 23 for the spring 9 is provided to constantly press the spring 9 forward to a position where it is blocked by a stopper 25 by a spring 24 stronger than the spring 9. In addition, a stopper 26 for adjusting the opening is provided, and its tip corresponds to the spring receiving member 23, and a stopper 12 for adjusting the opening is provided on the spring receiving member 23, and its tip is connected to the piston 8. In addition, for pressurized air to the cylinder 7, a branch pipe is provided in the outlet line of the switching valve 21 in the control air supply facility of the pressure regulator 16, and this is connected to the inlet of the on-off switching valve 11. In the illustrated resting state, the spring receiving member 23 is pressed forward by the spring 24 to be blocked by the stopper 25, and the spring 9 serving as a foothold pushes the piston 8 and the needle valve 3 forward. During spraying, low pressure air is supplied to the cylinder 7, so the spring receiving member 23 is kept in the same position as in the rest state. , while compressing the relatively weak spring 9, the piston 8 is moved back to a position where it is blocked by the stopper 12, so that the needle valve 3 is opened with a limited opening area; , high-pressure air is supplied to the cylinder 7, which first compresses the weak spring 9 and causes the piston 7 to collide with the stopper 12, and then pushes the spring receiving member 23 against the strong spring 24 via the stopper 12. Then, the needle valve 3 is moved back to a position where it is blocked by the stopper 26, and the needle valve 3 is moved back greatly, thereby significantly expanding the flow area of the valve device 4.

The pressure regulating device 16 includes a primary inlet 27 and a secondary outlet 28 as shown in the figure.
In addition, there is a relatively weak spring 29 near the inlet 27.
The valve chamber 31 provided with the valve body 30 that closes with Diaphragms 34 and 35 are interposed between the chambers 22, 33, and 31, and the valve chamber 31
It is preferable that the side diaphragm 35 and the valve body 30 are connected by a valve stem 36, and that the diaphragms 34 and 35 face each other at the center so that they interlock. Room 22
Alternatively, even if the diaphragm 34 or 35 is deformed due to a sudden change in the internal pressure of the valve chamber 31, this is absorbed in the relay chamber 33 and the influence on the other side is alleviated,
It is able to accurately transmit pressure changes mechanically in the center to provide stable pressure adjustment with quick response, and has excellent restorability, making it suitable for high-speed intermittent liquid supply. In addition, it is suitable as a pressure regulating device when a significant pressure difference is required in the secondary side pressure, such as during spraying and washing.

In the illustrated embodiment, the present invention is applied to an air spray type painting device, but the present invention is not limited to this, and is not limited to this. It may be a liquid supply device in an apparatus, or a coating device using these devices.Furthermore, the valve device 4 itself is not limited to being built into a spray gun, and the valve device 4 can be used as a downstream device through the valve device. A device using liquid, such as an atomizing device or a spouting device, may be provided at a remote location.

As explained above, according to the present invention, the liquid at a constant pressure is supplied under the regulation of the valve device by the pressure regulating device which constantly controls the supplied liquid by air pressure. In the liquid supply device, the cleaning liquid is supplied to the primary side of the pressure regulating device, and the control air to the pressure regulating device is switched to high pressure to increase the secondary side pressure, thereby controlling the opening degree of the valve device. Even if no adjustment is made, a large amount of cleaning solution can be easily passed through in a short time, and cleaning efficiency can therefore be significantly improved. Ideal for painting equipment.

[Brief explanation of drawings]

FIG. 1 is a system diagram including a cross section showing one embodiment of the cleaning device of the present invention, and FIG. 2 is a system diagram including a cross section showing another embodiment. 4...Valve device, 14...Liquid supply source, 15...
Switching valve, 16... Pressure adjustment device, 17... Washing liquid supply source, 18... Pressure air source, 19... Pressure air source, 21... Switching valve, 22... Pressure regulation chamber.

Claims (1)

[Scope of utility model registration request] A liquid adjusted to a constant pressure by a pressure-reducing valve-type pressure regulator 16 that adjusts the secondary liquid pressure using pressurized control air is supplied under the regulation of a valve device that limits the flow rate. In this liquid supply device, a liquid supply source 14 and a cleaning liquid supply source 17 for cleaning the liquid from the liquid supply source are connected to the primary side of the pressure regulating device 16 by a switching valve 15.
The pressure regulating chamber 2 of said pressure regulating device 16 is connected in such a way that it can be selectively switched under the intervention of
Pressure air sources 18 and 19 are connected to the switching valve 21 so that low pressure air and high pressure air can be selectively supplied to the switching valve 21, and the switching valve 15 is switched to the cleaning liquid. A cleaning device configured to switch a valve 21 to high pressure air supply.