JP3222091U - Reducer - Google Patents

Abstract

To separate and remove air bubbles with a small size, light weight, and simple configuration with respect to a coating liquid discharged in a bubble flow state accompanied by pulsation from a discharge pump of a coating apparatus, and reduce pulsation, thereby reducing coating. A de-energizer for decelerating and gently flowing the fluid flow into the fluid container. A cylindrical space having a larger flow area than the inflow hole 225 by widely securing an upper space from the inflow hole 225 inside a decelerator 24 having an inflow hole 225 on a substantially side surface. A guide path 246 is provided in the form of a curved wall, and the upper portion is closed by a sealing lid 245, and the lower portion is penetrated to form a sealing lid 245. By equipping the exhaust pipe 244 which extends to near, the flow velocity is reduced by sudden expansion loss, bending loss and eddy loss, and it is made to change from pulsating flow in the pipe to low pulsating flow flowing with free surface, and further from outlet hole 242 The tube 226 was extended downward. [Selected figure] Figure 3

Description

  The present invention relates to a decelerator installed in a coating fluid discharge flow path of a coating fluid circulation device used for a printing machine, a varnish coater, a gravure roll coater or other coating device.

  The coating liquid circulation system includes a supply pump that supplies the coating liquid from the liquid container to the coating liquid chamber, a discharge pump that discharges the coating liquid from the coating liquid chamber to the liquid container, a pipe that connects each of them The coating solution is circulated by valves and the like. The main coating liquids include printing inks, varnishes, adhesives, and liquid resins.

  The coating liquid is fed into the coating liquid chamber and is subjected to the coating processing through the engraving roller, while the cells on the engraving roller have an amount of air corresponding to the amount finished coating. It takes in and comes back into the coating liquid chamber. Therefore, air is mixed in the form of bubbles in the coating liquid discharged to the liquid container by the discharge pump. When air bubbles are mixed in the coating liquid, the coating quality such as the concentration, smoothness and gloss of the coating is deteriorated. Therefore, it was mixed in the coating liquid discharge flow path from the coating liquid chamber to the liquid container. It is necessary to separate and remove air bubbles.

  A reciprocating pump is used for the coating liquid circulation device for the convenience. However, the reciprocating pump has a drawback that the discharge amount pulsates because the volume is changed by the reciprocating motion to repeat suction and discharge. If there is pulsation in the coating liquid pumped from the discharge pump, it will vigorously blow out toward the liquid surface of the liquid container, and when it comes in contact with the liquid, it will spring up or rumble on the liquid surface to generate new bubbles. It will In order to flow gently into the liquid level in the liquid container, it is necessary to reduce the pulsation and slow the flow rate. The devices for damping pulsation include a pulsatile or diaphragm pulsating attenuator and a gas surge tank pulsator, but these pulsator damping devices have a predetermined value on the discharge side to obtain a damping effect. There is a disadvantage that a pipe length accompanied by piping resistance is required, and it is not suitable for miniaturization.

  The method of performing gas-liquid separation by the centrifugal force by eddy current is described in patent document 2 etc. In a conventional coating fluid circulation system that measures pulsation damping using a gas surge tank type pulsation attenuator, bubbles are taken into compressed air in the pulsation attenuator to simultaneously separate and remove the bubbles. ing. Therefore, although the bad influence to the coating quality by air bubbles has been eliminated, miniaturization could not be performed.

JP-A-59-230665 JP 2000-117002 A JP, 2008-196848, A

  The gas-liquid two-phase flow in which the air and the coating liquid coexist is discharged as a bubble flow from the coating liquid chamber. The object of the present invention is to attach to the coating liquid discharge flow path from the discharge pump to the liquid container, to easily separate and remove air bubbles mixed from the bubble flow, and the energy of the coating liquid flow The coating liquid is gently applied to the liquid container without causing blowout or splashing and generating new bubbles when the liquid is deposited on the liquid surface in the liquid container by reducing the flow velocity. The present invention is to provide a reducer which can be poured.

This invention is
A decelerator installed in a coating liquid discharge flow path for discharging a coating liquid from a coating apparatus and returning it to a liquid container,
An inflow hole of the coating liquid pressure-fed through the coating liquid discharge channel;
A receiving chamber having a substantially cylindrical curved wall whose downstream side is open, the upstream side being formed at a position eccentric from the center of the cylinder, and the upper and lower portions being closed;
At least one or more curved channel chambers having a curved wall in communication with the receiving chamber on the downstream side of the receiving chamber and changing the flow direction, the upper and lower portions being closed;
A reflux chamber in communication with the curved flow channel chamber on the downstream side of the curved flow channel chamber, having a substantially cylindrical curved wall, and closed at the top;
Outflow holes of the coating liquid formed in the lower part of the reflux chamber,
And a tube extending downward from the outlet hole;
The cross-sectional area of the flow passage from the receiving chamber to the reflux chamber is a de-energizer that is larger than the cross-sectional area of the inflow hole.

Here, the reducer according to the present invention is, as one aspect,
It is possible to adopt a configuration further including a liquid guide member having a descending slope and disposed below the tube.

In addition, the energy reducer according to the present invention is, as another aspect,
The height from the center of the inflow hole to the upper portion is larger than the height from the center of the inflow hole to the lower portion,
It is possible to adopt a configuration further including an exhaust pipe which has a gap between the upper portion and the lower portion and which penetrates the lower portion.

Further, as another aspect of the present invention, there is provided a reducer according to the present invention,
The upper wetted side may have a groove extending from the receiving chamber to the reflux chamber.

In addition, as a further aspect, the reducer according to the present invention,
The cross-sectional area of the outlet can be larger than the cross-sectional area of the inlet.

In addition, as a further aspect, the reducer according to the present invention,
It is possible to adopt a configuration in which the cross-sectional area of the flow passage in the curved flow passage chamber becomes larger toward the downstream side.

  With respect to the coating liquid pumped from the coating apparatus through the coating liquid discharge flow path, an expansion loss, a bending loss and an eddy loss are caused, the energy of the pulsating flow is dissipated, the flow velocity is reduced, and the flow is a hose There is a large enough volume to be able to change the aspect from a closed type pipeline flow confined by a wall or a joint etc. to a flow with a free surface such as an open channel, and a means of ventilating with the outside air is provided. Pulsation is reduced by changing the flow path to the open type flow path. Furthermore, gas-liquid separation is performed by centrifugal force due to swirling, and air bubbles are exhausted and removed through the aeration means. In order to achieve these effects, three chambers (spaces) including a receiving chamber, a curved flow passage chamber and a reflux chamber, and a tube are provided, and further, an exhaust pipe and / or a liquid guide member is optionally provided.

  A receiving chamber is formed that is wider than the cross-sectional area of the hose, the joint, or the like at the inflow hole, and the receiving chamber is formed of a substantially cylindrical curved wall. When the coating fluid flows into the receiving chamber, the flow direction swirls along the substantially cylindrical curved wall to induce a vortex. The expansion loss and the eddy loss reduce the flow velocity, and further, the action of the centrifugal force causes the mixed bubbles to be collected at the vortex center and separated. The flow through the receiving chamber bends and communicates with the flow passage chamber. The single or multiple curved flow path chambers are formed of curved walls comprising an inclined wall which is inclined with respect to the flow direction of the coating liquid which has exited from the receiving chamber and an arc wall. The arc wall further diverts the flow direction to give a bending loss to further slow down the coating liquid. Next, the flow passing through the curved flow passage chamber enters the reflux chamber. The reflux chamber has, at its lower portion, a circular outlet hole having a cross-sectional area larger than the cross-sectional area of the inlet hole, and is constituted by a substantially cylindrical curved wall. The coating liquid that has entered the reflux chamber is capable of generating a forced vortex by causing the flow to be inductively converted to an annular flow having an annular streamline just before the outlet hole, and air that sucks air from the outlet hole through the air column. Create a state in which the vortex of the The vortex of air extends to the center of the tube connected to the outflow hole, while the coating liquid flows down along the inner wall of the tube in a spiral, and along the liquid guide member having a descending slope Gently pour into the fluid container.

  An exhaust pipe is provided at any position of the receiving chamber, the curved flow path chamber and the reflux chamber, and the upper end thereof is extended near the upper portion in the vessel and the lower end is connected to the upper portion of the liquid container. In addition, a space above the center of the inflow hole of the decelerator is widely provided as a space for the air to move. By doing so, the separated air bubbles can be transmitted through the upper part in the pressure reducing device by the exhaust stack, and can be exhausted from the upper end of the exhaust stack to the liquid container. Furthermore, since the exhaust cylinder can ventilate the interior of the pressure reducing device, it contributes to converting the pulsating flow flowing in from the inside of the hose into an open type flow, and pulsation reduction is achieved in combination with widely secured volume and energy loss.

  The energy absorber according to the present invention is wider than the cross-sectional area of the inflow hole, and by providing the coating liquid with expansion loss, bending loss and eddy loss, by configuring the space in an inner space connected with curved walls, the flow Energy can be dissipated to slow the flow rate. Moreover, the bubble mixed in the coating liquid can be isolate | separated by inducing a vortex phenomenon.

  In addition, when a wide space is provided above the center of the inflow hole of the reducer and the exhaust pipe is provided, the air separated by the vortex phenomenon can be removed by using the exhaust pipe. Furthermore, pulsation can be reduced by changing the appearance of the pulsating flow flowing from the inside of the hose into an open type flow having a free surface by ventilating the exhaust stack and the space volume widely secured in the pressure reducing device. By connecting the tube to the outlet hole, a vortex of air can be induced in the center of the tube, and the coating liquid can flow down along the inner wall of the tube in a spiral. This eliminates the phenomenon of blowing out with the air bubbles. If a liquid guide member having a downward slope is provided, the coating liquid flowing down along the inner wall of the tube can be gently deposited in the liquid container.

  As described above, the decelerator according to the present invention removes bubbles from the coating liquid sent as bubble flow accompanied by pulsation, slows down the flow velocity, reduces pulsation and gently reaches the liquid surface. The liquid can be deposited, and the problem of further increasing bubbles in the liquid container does not occur. In addition, since it can be easily configured to be small and light, it can be disposed on the top of the liquid container, which contributes to the miniaturization of the coating liquid circulation device.

It is a perspective view of a representative coating device in which a coating fluid circulation device concerning one embodiment of the present invention is used. It is explanatory drawing which showed the mode of coating typically. It is a top view of the energy-saving device installed in the coating fluid circulation device. It is a sectional view of the same energy reducer. It is a perspective view of the same energy saving device. It is a front view of a small coating fluid circulation device equipped with the same energy saving device. FIG. 7 is a plan view of a reducer according to another embodiment. And FIG. 7 is a cross-sectional view of a decelerator according to yet another embodiment.

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

  As shown in FIG. 1, the coating apparatus 1 holds the coating liquid 5 supplied to the coating liquid chamber 3 from the supply pump 21 in the coating liquid circulation apparatus 2 on the surface of the rotating engraving roller 4. And transfer to the surface of the material to be treated (not shown). As shown in FIG. 2, the engraving roller 4 has fine cells on its surface, and the coating liquid 5 supplied into the coating liquid chamber 3 enters the cell and is filled with the coating liquid 5. The discharged cells are delivered from the coating liquid chamber 3. When the engraving roller 4 transfers the coating fluid film 51, the half of the coating fluid 5 remaining in the cell remains. When the cells after transfer return to the coating liquid chamber 3 again with the air 6, the air 6 becomes air bubbles 61 in the coating liquid chamber 3 and is released into the coating liquid 5. The cell replaced with the coating liquid 5 by the action of the flow velocity and the pressure and returned is filled again with the coating liquid 5 in the coating liquid chamber 3. The cells shown in FIG. 1 and FIG. 2 are schematically represented quite large for ease of explanation, but actually they are fine recesses of about 20 to 130 μm in size and which can not be seen with the naked eye. In order to prevent the air bubbles 61 from staying and growing in the coating liquid chamber 3, the coating liquid circulation device 2 is generally equipped with a discharge pump 22, and the coating liquid 5 is forced from the coating liquid chamber 3. The amount of circulation is increased by discharging. The air bubbles 61 deteriorate the coating quality such as the concentration, smoothness and gloss of the coating liquid. In the coating liquid circulation device 2, the circulation amount of the coating liquid 5 is increased by the supply pump 21 and the discharge pump 22 so that the air bubbles 61 are promptly removed from the cells to maintain the stability of the coating quality.

  FIG. 3 is a plan view of the reducer 24 with the sealing lid 245 removed. FIG. 4 shows a cross sectional view. The energy reducer 24 is composed of three chambers, a receiving chamber 241, a curved flow passage chamber 246 and a reflux chamber 243. However, the curved flow path chamber 246 can be further increased. The number of curved flow path chambers 246 and the extension distance of the curved wall are set according to the flow rate range and viscosity of the coating liquid to be operated.

  All of the flow paths in the interior space of the reducer 24 are formed to have a cross-sectional area that is larger than the cross-sectional area of the inflow hole 225. The receiving chamber 241 is formed of a curved wall including a cylindrical wall 240 which is open on the downstream side and extends in a substantially vertical direction. When the coating liquid is received by the cylindrical wall 240, the receiving chamber 241 swirls in the flow direction approximately 180 ° along the cylindrical wall 240 and induces the vortex 10. Due to the action of the centrifugal force of the vortex, the mixed air bubbles gather at the center of the cylindrical surface. The flow passing through the receiving chamber 241 is in communication with the curved flow passage chamber 246. The curved flow path chamber 246 is formed of a curved wall including an inclined wall 227 and a circular arc wall 228 which extend in the substantially vertical direction and which is inclined with respect to the flow direction of the coating liquid coming out of the receiving chamber 241. The flow is further diverted in the flow direction by the arc wall 228 and enters the reflux chamber 243. The reflux chamber 243 has a circular outlet hole 242 having a cross-sectional area larger than the cross-sectional area of the inlet hole 225 on the lower surface, and is a cylinder that is larger than the outlet hole 242 and extends in a substantially vertical direction It comprises a curved wall consisting of walls 240. The coating liquid that has entered the reflux chamber 243 is inductively converted to the reflux 14 by the cylindrical wall 240 to generate a forced vortex, and a vortex 15 is generated from the outflow hole 242. A vortex 15 extends in the center of the tube 226 connected to the outlet hole 242, and the coating liquid flows down along the inner wall of the tube 226 in a spiral, and further a liquid guide member having a descending slope 247 Gently apply into liquid container 8 along H.248.

  In FIG. 3, the channel width of the channel in the curved channel chamber 246 is formed wider toward the downstream side (an exhaust cylinder provided apart from the inclined wall 277 and the arc wall 228 in the curved channel chamber 246) The effect of a so-called curved diffuser is obtained by the passage width S1 between 244 and the inclined wall 227, and the passage width S2 between the exhaust cylinder 244 and the arc wall 228), and the flow is further changed by the change in cross sectional area. It can be lossy and has the effect of increasing the damping effect.

  The sealing lid 245 serves to prevent the coating liquid from leaking out. The exhaust pipe 244 extends at the upper end near the sealing lid 245 in the curved flow path chamber 246 in the reducer 24, penetrates the lower surface of the reducer 24, and communicates with the upper space of the liquid container 8. There is. However, the exhaust cylinder 244 may be provided in the receiving chamber 241 or the reflux chamber 243, or may be provided in plurality instead of one. The separated air travels through the sealing lid 245 and is exhausted to the upper space of the liquid container 8 through the exhaust cylinder 244. To that end, each chamber in the decelerator 24 is formed such that the space above the center of the inflow hole 225 indicated by symbol b in FIG. 4 is wider. The coating liquid may intrude into the exhaust cylinder 244 depending on the amount of air bubbles, but since it flows into the liquid container 8, it does not leak out.

  The generation state of the vortex changes depending on the amount of air bubbles mixed, the flow rate of the coating liquid, the size of each chamber space in the attenuator 24, and the like. When the flow rate is low, a vortex in which air bubbles are collected is generated in the receiving chamber 241, and the upper end of the vortex of air moves to be connected to the exhaust pipe 244. In this case, the coating liquid flows as a gentle spiral from the outflow hole 242 and does not flow to the reflux chamber 243 without growing to a powerful vortex. When the flow rate is slightly increased, the air vortices formed in the receiving chamber 241 and the curved channel chamber 246 move to the outflow hole 242 of the reflux chamber, and become a stable vortex at the outflow hole 242. As the amount of air bubbles increases, the air vortices become larger, and the upper end of the vortices moves in communication with the exhaust cylinder 244, so the exhaust cylinder 244 exhausts part of the air bubbles that are not absorbed by the air vortex. When the flow rate further increases and exceeds the flow rate at which the air vortex can be generated in the receiving chamber 241, the reflux of the reflux chamber 243 increases its momentum, and a vortex of the coating liquid occurs in the outflow hole 242. Even when the flow rate increases, the diameter of the outflow hole 242 and the tube 226 is such that the coating liquid spirals down in the tube 226 and the air vortex is stably generated at the center of the tube 226. The bottom end of the vortex is stably and vertically grown to the lower end of the tubular body 226, and the coating liquid flows gently without runaway or diffusion. The air bubbles escape into the upper space in the liquid container 8 by the vortex at the cylinder center of the outflow hole 242.

  FIG. 5 shows a groove 249 provided in the sealing lid 245. By providing the groove 249, the air vortex 10 can be easily connected to the exhaust cylinder 244 even if the position thereof is moved depending on the flow rate.

  FIG. 6 shows the coating liquid circulation system 2 equipped with the energy reducer 24. The pulsation attenuator 25 is an air chamber and buffers pulsations to the coating liquid discharged from the supply pump 21. Thereafter, the coating liquid is fed from the coating liquid supply side hose connection port 235 toward the coating liquid chamber 3. On the other hand, the discharge pump 22 sucks the coating liquid with air bubbles from the coating liquid chamber via the coating liquid discharge side hose connection port 223. Thereafter, the coating liquid enters the decelerator 24, is conditioned and flows into the liquid container 8. The pulsation attenuator 25 can obtain a predetermined attenuation effect because a pipe length with a predetermined pipe resistance can be obtained by the hose from the coating liquid supply side hose connection port 235 to the coating liquid chamber 3. Instead of equipping the discharge side with the same pulsation attenuator 25, instead of using the energy reducer 24, it can be compact and can be installed just before the liquid container 8, and the coating liquid circulation system 2 can be miniaturized. I have to.

  FIG. 7 shows another embodiment of the energy reducer 24. Although the configuration of the three chambers is the same as that of the above-described attenuator 24, this is an example in which the curved wall of the curved flow channel chamber 246 is expanded to approximately 180 °.

  Referring to FIG. 8, yet another embodiment of the energy reducer 24 is shown. It is a structural example which has the exhaust pipe | tube 260 which passes through the outflow hole 242 and the pipe body 226. FIG. Depending on the difference in viscosity of the coating liquid, it may be easier to remove air bubbles if the exhaust cylinder 260 is provided in the outflow hole 242.

  In addition, the damping device which concerns on this invention is not limited to what was demonstrated until now, A various change is possible in the range which does not deviate from the summary of this invention.

DESCRIPTION OF SYMBOLS 1 Coating apparatus 2 Coating liquid circulation apparatus 3 Coating liquid chamber 4 Engraving roller 5 Coating liquid 6 Air 8 Liquid container 9 Liquid container conduit 10 Vortex 14 Recirculation 15 Vortex 21 Supply pump 22 Discharge pump 24 Decompression device (paint Decompressor for industrial fluid discharge pump)
31 Coating liquid chamber supply side hose joint 32 Coating liquid chamber discharge side branch hose joint 33 Coating liquid chamber discharge side hose joint 41 Cell filled with coating liquid 42 Cell after transfer 51 Coating transferred from engraving roller Working fluid film 61 Bubbles 223 Coating fluid discharge side hose connection port 224 Coating fluid discharge pipe 225 Inflow hole 226 Tube body (short pipe)
227 inclined wall 228 arc wall 235 coating liquid supply side hose connection port 240 cylindrical wall 241 receiving chamber 242 outflow hole 243 reflux chamber 244 exhaust cylinder 245 closed lid 246 curved channel chamber 247 descending slope 248 liquid guide member 249 groove 260 exhaust cylinder

In addition, the energy reducer according to the present invention is, as another aspect,
The height from the center of the inlet to the top of each of the receiving chamber, the curved channel and the reflux chamber is greater than the height from the center of the inlet to the lower portion of the receiving chamber, the curved channel and the reflux chamber ,
Receiving chamber, to any of the curved flow passage chamber or reflux chamber, can be employed Bei obtain an exhaust tube penetrating the lower portion with a gap between the upper.

Further, as another aspect of the present invention, there is provided a reducer according to the present invention,
The liquid contact side of the receiving chamber, the curved flow passage chamber and the upper portion of the reflux chamber may be configured to include a groove extending from the receiving chamber to the reflux chamber.

Claims (6)

A decelerator installed in a coating liquid discharge flow path for discharging a coating liquid from a coating apparatus and returning it to a liquid container,
An inflow hole of the coating liquid pressure-fed through the coating liquid discharge channel;
A receiving chamber having a substantially cylindrical curved wall whose downstream side is open, the upstream side being formed at a position eccentric from the center of the cylinder, and the upper and lower portions being closed;
At least one or more curved channel chambers having a curved wall in communication with the receiving chamber on the downstream side of the receiving chamber and changing the flow direction, the upper and lower portions being closed;
A reflux chamber in communication with the curved flow channel chamber on the downstream side of the curved flow channel chamber, having a substantially cylindrical curved wall, and closed at the top;
Outflow holes of the coating liquid formed in the lower part of the reflux chamber,
And a tube extending downward from the outlet hole;
The cross-sectional area of the flow passage from the receiving chamber to the reflux chamber is larger than the cross-sectional area of the inflow hole. The energy reducer according to claim 1, further comprising a liquid guide member having a descending slope and disposed below the tube. The height from the center of the inflow hole to the upper portion is larger than the height from the center of the inflow hole to the lower portion,
The reducer according to claim 1, further comprising: an exhaust pipe having a gap between the upper portion and the lower portion and having a gap. The dehumidifier according to any one of claims 1 to 3, wherein the liquid contact side of the upper portion includes a groove extending from the receiving chamber to the reflux chamber. The reducer according to any one of claims 1 to 4, wherein the cross-sectional area of the outflow hole is larger than the cross-sectional area of the inflow hole. The reducer according to any one of claims 1 to 5, wherein the cross-sectional area of the flow passage in the curved flow passage chamber increases toward the downstream side.

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