JPH085421Y2 - Fluid switching valve for painting - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The present invention relates to a coating fluid switching valve used for switching of these coating fluids and discharge control in order to supply coating fluid and its solution to a coating gun. .

(Prior Art) When switching paints using this type of fluid switching valve for painting, for example, as shown in FIG.
Taking as an example the case where the paint to be sprayed onto the paint is changed from paint A to paint B, the changeover valve 102 and the changeover valve 103 for controlling the discharge of the paint (putting it out or stopping) are put into the discharge state, and the pressure air is discharged. 104 pushes the paint A in the container 105, and the paint A is sprayed from the paint gun 107 through the common passage 106 and the compressed air 108 onto the object 109 to be coated.

When the coating gun 107 is moved to change the coating surface of the object to be coated 109 during coating, the switching valve 103 is closed to suspend the spraying of the coating material A.

When the painting of the paint A is completed, the changeover valve 102 is put into the common passage 106 and the changeover valve 103 in order to wash the paint A adhering in the common passage 106 and the changeover valve 103 after switching the discharge valve 102 to the discharge stop state.
Is discharged, and a solution such as thinner in the container 111 is sent into the common passage 106 and the switching valve 103 by the compressed air 112 for cleaning.

After that, the switching valve 110 is set to the discharge stop state, and the switching valve 113 is set to the discharge state for drying, and the blowing air 114 is sent.

Next, when the switching valve 113 is put into the discharge stop state and then the switching valve 115 is put into the discharge state, the pressure air 116 pushes out the paint B in the container 117, whereby the paint B passes through the common passage 106 and the changeover valve 1.
It is sprayed from the coating gun 107 to the object 109 to be coated through 03.

The control of each of the above-mentioned switching valves and the like is performed by the control unit 101.
By a control signal from.

Conventionally, for example, a pilot two-way valve as shown in FIG. 4 has been used as a switching valve for controlling the supply of paint or solution to a coating gun.

This pilot two-way valve is mounted with a cylindrical valve body 119 on one side across a partition member 118 in the center and a piston body 121 which is a drive unit body on the other side. The valve body 119 is provided with an input port 122 for supplying paint, solution, etc., and the input port 122 has a communication passage 122A.
And communicates with the valve chamber 123 inside the valve body 119 in an orthogonal state. A valve seat 124 is provided at the bottom of the valve body 119 located at the lower end of the valve chamber 123, and the valve seat 124 is a seat member made of an elastic member such as Teflon having an output port 125 formed in the center. It is fixed by a valve seat retainer 126 attached to the bottom surface of the valve body 119.

An internal chamber 120 is formed in the piston body 121, and a breathing hole 121A that connects the internal chamber 120 and the outside is provided. The inner chamber 120 has an annular groove 128A formed in the outer peripheral portion.
A piston 128 having a piston seal 129 mounted therein is housed therein, and the piston 128 is biased toward the valve body 119 by a spring 127.

Also, a female screw 128B is cut at the axial center of the piston 128,
A valve rod 130 having an intermediate portion with a male screw 130A screwed to the female screw 128B is integrally fixed. A main valve 131 seated on the valve seat 124 is formed at the tip of the valve rod 130, and the other end of the valve rod 130 is slidably supported by a bush 132 attached to the upper side of the piston body 121. There is.

A piston chamber 13 is provided between the piston 128 and the partition member 118.
3 is formed, and the piston chamber 133 is communicated with each other through a communication passage 134A so that pilot air is introduced from a pilot port 134 formed on the outer peripheral portion of the piston body 121. Around the valve rod 130, the main valve 131 and the partition member 11
An elastic member 135 such as a bellows is provided so as to be connected to the lower end of 8. The expansion and contraction member 135 attaches the valve rod 130 to the valve chamber 123.
The piston chamber 133 is hermetically sealed so as to be shielded from the paint and the like therein so that the paint and the like adhere to the valve rod 130 and the opening / closing operation of the valve is not impaired. Incidentally, reference numerals 136, 137, 138, 139
Are packings for sealing with O-rings or the like.

Next, the operation of the pilot two-way valve will be described. When pilot air is supplied from the pilot port 134 into the piston chamber 133 by a signal from the control unit 101, the piston 128 and the valve rod 130 rise against the biasing force of the spring 127, and the main valve 131 moves to the valve seat 124. The output port 125 is opened apart from, and the input port 122 and the output port 125 are communicated with each other via the communication passage 122A and the valve chamber 123.

When the supply of pilot air into the piston chamber 133 is stopped, the piston 128 is urged by the urging force of the spring 127.
Also, the valve rod 130 descends, the main valve 131 abuts the valve seat 124, and closes the output port 125, so that the flow path that was in communication is cut off.

Therefore, when the pilot two-way valve is used as the switching valve 103 in FIG. 3 to perform the cleaning work during the switching between the paint A and the paint B, the pilot from the pilot port 134 by the signal from the control unit 101. When air is supplied, the solution such as thinner supplied from the input port 122 cleans the inside of the valve chamber 123 and is discharged from the output port 125.

In this way, various kinds of paints are supplied to the inside of the switching valve 103 that controls the supply of paint or solution to the coating gun in the coating facility, and the valve chamber is washed with a solution such as thinner at each switching, Air blow for drying is performed.

(Problems to be solved by the invention) However, in the conventional switching valve with the above structure, the input port
The communication passage 122A for supplying fluid from the valve chamber 123 to the valve chamber 123
Since the fluids such as paint and solution supplied collide with the elastic member 135 in an orthogonal state to form a complicated flow path in which the fluids interfere with each other, the fluid energy Is consumed and the flow velocity is slowed, and the elastic member
There was a problem that the fluid was accumulated in the valleys of 135 and the packing 136, and the paint could not be sufficiently washed, and the previous color was mixed with the next color.

In view of the above, the present invention solves the above-mentioned problems of the conventional switching valve, improves the cleanability of the valve chamber, prevents the coating fluid from staying, prevents deterioration and solidification, and improves valve operation failure. The purpose is to provide a fluid switching valve.

(Means for Solving the Problem) In order to solve such a problem, in the fluid switching valve for painting of the present invention, an annular packing is attached to a root portion of the valve rod protruding from the partition member to the valve chamber, The communication passage leading from the input port to the valve chamber deflects the inflowing fluid with respect to the axial center of the valve rod including the main valve so as not to be orthogonal to the axial center of the valve stem, and first injects the fluid into the annular packing. So that the fluid injected into the annular packing spirally swirls along the outer periphery of the valve rod from the partition member side to the output port side. Configured.

(Embodiment) Hereinafter, a coating fluid switching valve according to the present invention will be described in detail with reference to an embodiment shown in FIGS. 1 and 2. The pilot two-way valve 1 has a cylindrical valve body 3 mounted on one side of a partition member 2 formed in the center and a piston body 5 serving as a drive unit body mounted on the other side.

An internal chamber 4 is formed in the piston body 5, and a breathing hole 24 that connects the internal chamber 4 and the outside is provided.
A piston 14 having a piston seal 15 mounted in an annular groove 14A formed in the outer peripheral portion is housed in the internal chamber 4, and the piston 14 is biased toward the valve body 3 by a spring 13.
Further, a female screw 14B is cut at the axial center of the piston 14, and a valve rod 16 having a male screw 16A screwed to the female screw 14B in the middle portion.
Are fixed together. The main valve at the tip of this valve rod 16
17 is formed, and the other end of the valve rod 16 is slidably supported by a bush 6 attached to the upper side of the piston body 5.

A piston chamber 18 is formed between the piston 14 and the partition member 2, and the piston chamber 18 has a pilot port 20 formed in an outer peripheral portion of the piston body 5 and a pilot passage 20 through which a pilot air is introduced. Are in communication.

The valve body 3 is provided with an input port 7 for supplying a coating fluid such as paint or solution, and the input port 7 communicates with a valve chamber 9 inside the valve body 3 via a communication passage 8.
The communication passage 8 is deflected with respect to the axial center of the valve chamber 9 so as not to be orthogonal to the axial center of the valve chamber 9, and is provided so as to be inclined upward toward the partition member 2.

At the bottom of the valve body 3 located at the lower end of the valve chamber 9, there is provided a valve seat 10 with which the main valve 17 formed by the tip of the valve rod 16 can come into contact, and the valve seat 10 outputs at the center. It is a seat body made of an elastic member such as Teflon which forms the port 11, and is fixed by a valve seat retainer 12 attached to the bottom surface of the valve body 3.

An annular packing 21 having a U-shaped cross section is provided in the valve chamber 9 for sealing the boundary with the partition member 2 on which the valve rod 16 slides. The annular packing 21 allows the inside of the valve chamber 9 to be sealed. Of the paint or the solution is prevented from entering the piston chamber 18 side. Further, in the valve chamber 9, a packing retainer for pressing the annular packing 21 at the boundary between the partition member 2 and the valve body 3.
22 is provided, and the end of the packing presser 22 has an annular packing 21 for the paint and solution supplied through the communication passage 8.
Chamfered to make it easier to reach the side.

Further, the partition member 2 is provided with a volatilization chamber 23 for vaporizing a small amount of the solution adhering to the valve rod 16 when it leaks to the upper part of the annular packing 21, and the volatilization chamber 23 is continuously connected. It communicates with the atmosphere via a passage 24.

Next, the operation of the pilot two-way valve will be described. When pilot air is supplied from the pilot port 20 into the piston chamber 18 by a signal from the control unit 101, the piston 14 and the valve rod 16 rise against the biasing force of the spring 13,
The main valve 17 is separated from the valve seat 10 to open the output port 11, and the input port 7 and the output port 11 are communicated with each other via the communication passage 8 and the valve chamber 9.

When the supply of pilot air into the piston chamber 18 is stopped, the piston 14 and the valve rod 16 are lowered by the urging force of the spring 13, and the main valve 17 comes into contact with the valve seat 10 and the output port.
Since 11 is closed, the flow path that was in communication is blocked.

Therefore, in the case where the pilot two-way valve is used as the switching valve 103 in FIG. 3 and the cleaning work of the paint A adhering to the inside of the flow path during the switching of the paint A to the paint B is performed, control is performed. When pilot air is supplied from the pilot port 20 by the signal from the section 101, the input port 7
The solution such as thinner supplied from the inside of the valve chamber 9 is washed and discharged from the output port 11.

In this case, the solution flowing into the valve chamber 9 is deflected from the communication passage 8 with respect to the axial center of the valve rod or the like so as not to be orthogonal to the axial center, and is inclined upward to form the valve rod 16 at the upper portion of the valve chamber. Since it is jetted toward the outer periphery of the sliding part of the valve, first, the raised fluid cleans the U-shaped inside of the annular packing 21, the sliding part of the packing retainer 22 and the valve rod 16, and then the While spirally swirling in the valve chamber 9 along the outer periphery as shown by the arrow, it flows without staying and is sequentially discharged from the output port 11 at the lower part of the valve chamber.

In this way, the paint A attached to the valve rod 16 and the annular packing 21 and remaining in the valve chamber 9 is discharged while being easily and surely washed by the solution without being altered or coagulated. Since the solution used for cleaning is dried by the blown air 114 sent next, good coating can be performed without mixing with another paint B to be changed and used next.

Further, even a small amount of the solution that has leaked to the partition member 2 side along the valve rod 16 is communicated to the atmosphere side through the communication passage 24.
Therefore, the sliding of the valve rod 16 is not impaired.

Although the two-port valve has been described in the above embodiment,
It can also be applied to a 3-port valve that switches fluid from an input port to either of two output ports.

(Effect of the Invention) As is apparent from the above-described embodiments, in the fluid switching valve for coating of the present invention, the fluid is deflected with respect to the axial center of the valve rod, and the communication passage is provided so as to be inclined upward toward the partition member. The fluid that flows into the valve chamber is injected into the annular packing that is attached to the root of the valve rod that slides against the partition member, and this fluid flows from the partition member side to the output port side around the outside of the valve rod. The fluid is discharged through the fluid flow path that spirally swirls along, but the following effects can be obtained.

(1) When the paint is washed, the solution such as thinner that has flowed into the valve chamber through the communication passage does not directly collide with the valve stem, and is smooth along the outer periphery of the base of the valve stem and the wall surface of the valve chamber. After cleaning the paint adhering to the annular packing while flowing, the solution swirls around the outer circumference of the valve rod toward the output port and is discharged from the output port together with the removed paint. Therefore, the cleanability is remarkably improved as compared with the above-described conventional coating fluid switching valve. In this case, in particular, by spraying the solution onto the annular packing, it is possible to achieve a good cleaning effect on the annular packing where the paint is likely to adhere and the sliding portion of the valve rod where the valve opening / closing operation may be impaired due to the adhesion of the paint. it can.

(2) Even when the coating material is supplied, the coating material flows without being retained in the valve chamber by the same fluid flow path as the above-described cleaning solution, so that the deterioration and solidification of the coating material due to the retention can be prevented. Of course, in particular, the paint does not stay in the sliding portion between the annular packing and the valve rod, which constantly receives the injection of new paint, and the paint that adheres in the residual state is reduced, so that the valve opening / closing operation is not impaired.

(3) Even in the case of air blow in which the solution is dried after cleaning, the cleaning solution that has penetrated into the narrow gap can be sprayed because it is sprayed on the sliding part between the annular packing and the valve rod by the same fluid flow path as the cleaning solution described above. It can be dried quickly and reliably.

(4) By omitting the elastic member such as the bellows used in the above-described conventional structure for covering the outer periphery of the valve rod, the coating material stays in the valley portion of the elastic member, which is a problem of the conventional structure. It also solves the problem of adhesion and insufficient cleaning.

[Brief description of drawings]

1 is a vertical sectional view of a fluid switching valve for painting according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG.
FIG. 4 is a block diagram of a coating facility in which the coating fluid switching valve is used, and FIG. 4 is a vertical cross-sectional view of a conventional coating fluid switching valve. [Explanation of symbols] 1 …… Pilot 2-way valve 2 …… Partitioning member 3 …… Valve body 4 …… Internal chamber 5 …… Piston body (drive unit body) 6 …… Bushing 7 …… Input port 8,19, 24 ...... Communication passage 9 ...... Valve chamber 10 ...... Valve seat 11 ...... Output port 12 ...... Valve seat retainer 13 ...... Spring 14 ...... Piston 14A ...... Annular groove 14B ...... Female thread 15 ...... Piston seal 16 ... … Valve 16A …… Male thread 17 …… Main valve 18 …… Piston chamber 20 …… Pilot port 21,22 …… Annular packing 23 …… Volatile chamber 24 …… Breathing hole

Claims (1)

[Scope of utility model registration request] 1. A drive unit body is mounted on one side of a partition member, and a valve body is mounted on the other side of the partition member. The base end side of a valve rod into which the partition member is slidably inserted is operated in the drive unit body. A valve drive portion for advancing or retreating the valve rod between predetermined positions is accommodated, and the valve body has a valve chamber formed on the outer periphery of the valve rod in which the tip end side of the valve rod is accommodated; An input port that is open to the outer peripheral portion and communicates with the valve chamber via a communication passage is provided, and a main valve provided at the tip of the valve rod can abut on the extension line in the axial direction of the valve rod. In a coating fluid switching valve provided with a seat and an output port opening in the center of the valve seat whose flow path is opened and closed by the main valve, the valve rod is provided at a base portion protruding from the partition member into the valve chamber. Is an annular packing and connects to the valve chamber from the input port. Deflects the inflowing fluid with respect to the axial center of the valve rod including the main valve so as not to be orthogonal to the axial center of the valve stem, and upwardly directs the fluid toward the partition member so as to inject the fluid into the annular packing. The coating is characterized in that it is provided in a slanted shape and is configured as a fluid flow path in which the fluid injected into the annular packing spirally swirls from the partition member side to the output port side along the outer periphery of the valve rod. Fluid switching valve.