JP2006150149A - Mist injection valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mist injection valve capable of obtaining a correct spray pattern and spraying a fine mist even when a feeding water pressure to the mist injection valve is an approximately dynamic water pressure from a hot water feeding plug. <P>SOLUTION: In the mist injection valve 1 provided with a rotation flow generation chamber 14 of a circular cross section; one to a plurality of flowing-in ports 15 communicating with the rotation flow generation chamber 14 in an approximately tangent direction; and an injection port 16 opened to one end of the rotation flow generation chamber 14 and formed to an orifice shape coaxially to a central axis of the rotation flow generation chamber 14, all curved/bent parts of an inner wall surface from the rotation flow generation chamber 14 to an exit of the injection port 16 are formed by smooth curved surfaces. Thereby, generation of a turbulence disturbing a swirl flow at the inside of the rotation flow generation chamber is suppressed and even when an entering water pressure is low, an injected thin water film is sufficiently spread and turbulence of hollow-cone is decreased. Further, membrane-like disruption becomes good and even if an injection pressure is low, fine spraying can be obtained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mist injection valve used as a nozzle for generating mist in a mist / sauna apparatus or the like, and in particular, a water cone or hot water supplied at a low water pressure is used as a swirl flow (swirl flow). The present invention relates to a mist injection valve that injects in a (hollow-cone) shape.

  In recent years, mist / sauna devices have become widespread as devices for heating in bathrooms and enjoying saunas in home bathrooms. A mist / sauna device is a device that sprays hot water supplied from a water heater, a solar water heater, or the like into a bathroom as a hot water mist to heat the bathroom. In such a mist / sauna apparatus, a mist injection valve that sprays hot water as mist is used.

  As a mist injection valve for atomizing (misting) a fluid, various nozzles have conventionally been devised as pressure-type atomizing valves. Main pressure type atomization valves are classified into single injection nozzles, simple spiral injection valves, overlapping spiral injection valves, double injection nozzles, fan spray nozzles, reflux injection valves, etc. as shown in FIG. (See Non-Patent Document 1). In a device having a relatively low water pressure, such as a mist / sauna device, a swirl nozzle is generally used that can obtain a fine spray even at a low water pressure.

  FIG. 10 shows an operation principle diagram of a typical spiral injection valve (simple spiral injection valve). A swirl injection valve is a nozzle that uses a swirl flow to atomize a liquid by film splitting. Water supplied from a water supply or a water heater flows into the swirl flow generation chamber 102 from the inlet 101. The inflow port 101 is opened in the tangential direction on the side wall of the swirl flow generation chamber 102. The water that has flowed into the swirl flow generation chamber 102 swirls within the swirl flow generation chamber 102 due to the incoming water pressure. And it injects from the injection port 103 formed in the one end side wall of the swirling flow generation chamber 102 coaxially with the central axis of the swirling flow generation chamber 102. At this time, an air core 108 is formed on the central axis in the swirl flow generation chamber 102 from the injection port 103 to the swirl flow generation chamber 102 (see FIG. 10B). The injected water has a turning speed and an axial speed. Accordingly, as shown in FIG. 10, an empty conical thin water film (empty conical water film 104) is formed. Since the empty conical water film 104 generates vibrations having waves along the direction of motion, the holes 105 are finally formed in a direction perpendicular to the traveling direction, and the holes 105 expand immediately due to surface tension. The border becomes a string shape, then becomes a small string shape 106, and finally becomes fine particles to become a mist 107. Such a micronization process is called “membrane splitting”.

  Conventionally known simple spiral injection valves include those described in Patent Documents 1 to 3, for example. Here, a simple spiral injection valve described in Patent Document 1 will be described as a representative, and the configuration thereof is shown in FIG.

  The nozzle body 121 of the simple swirl injection valve 120 is composed of three parts: a housing part 122, a partition part 123, and a nozzle mouth body 124. The accommodating part 122 is a cylindrical tubular body in which an inlet 122a through which water flows is formed at one end and the diameter of the other end is increased. The partition part 123 is formed in a bottomed cylindrical shape in which a flange-like skirt part 123a is formed on the opening end side. The partition part 123 is inserted in the pipe of the enlarged diameter part of the accommodating part 122, and the edge part of the accommodating part 122 is closed by the skirt part 123a. A cavity inside the partition part 123 is a swirl flow generation chamber 125. An inlet 126 is perforated in one portion of the cylindrical side wall of the swirl flow generation chamber 125 in a substantially tangential direction of the cylinder. The introduction port 122a and the swirling flow generation chamber 125 are communicated with each other through an inflow port 126.

  On the skirt portion 123a side of the partition portion 123, a cylindrical nozzle mouth body 124 having a jet port 127 perforated along the central axis is fitted. The injection port 127 is formed in an orifice shape in which the central portion 124a has a reduced diameter. The injection port 127 is formed such that the tube wall of the inflow portion 124b on the swirl flow generation chamber 125 side has a truncated cone shape, and is reduced in diameter toward the central portion 124a at a constant angle. The inner wall surface of the central part 124a is formed in a right cylindrical shape. The outflow portion 124c is formed so that the opening area gradually increases in diameter. The inner wall surface of the injection port 127 from the central portion 124a to the outflow portion 124c is formed into a smoothly continuous curved surface (hereinafter referred to as “attachment surface”).

  The nozzle body 124 is screwed into the tube of the swirl flow generation chamber 125, and the maximum inner diameter of the inflow portion 124b of the injection port 127 is smaller than the inner diameter of the swirl flow generation chamber 125 by a certain length. The boundary between the portion 124b and the swirl flow generation chamber 125 is reduced in a stepped shape in order to ensure the outer threading of the nozzle mouth body 124.

  With this configuration, the mist is sprayed by the following spraying process. First, water or warm water (hereinafter referred to as “hot water”) flows from the inlet 122a. The hot water that has flowed in passes through the accommodating portion 122 and wraps around the periphery of the partition portion 123 and flows into the swirling flow generation chamber 125 from the inlet 126. The hot water flowing into the swirl flow generation chamber 125 becomes a spiral flow and is ejected through the ejection port 127. The injected hot and cold water spreads in the shape of an empty cone, and becomes fine particles by film splitting as described above. As a result, mist spraying is performed.

Here, since a smooth curved surface is formed from the central portion 124a to the outflow portion 124c of the injection port 127, when water is injected from the injection port 127, the hot water sprayed out while adhering to the adhesion surface. Is done. Therefore, the spray angle can be increased even when the hot water supply water pressure is small. That is, it is possible to efficiently generate membranous division and spray mist even at a low supply water pressure.
JP 2000-254556 A Japanese Unexamined Patent Publication No. 7-88531 Japanese Patent Laid-Open No. 11-151457 Supervised by Hiroaki Yanagida, “Partner Technology of Fine Particles, Volume 1”, first edition, Fuji Techno System, October 31, 2001, p. 269 Kobayashi Kiyoshi, Araki Nobuyuki, Makino Satoshi, "Mechanical Engineering Basic Course Combustion Engineering-Fundamentals and Applications", 1st Edition, Science and Engineering, Aug. 31, 1988, pp. 77-86

  However, when the mist / sauna device is used by directly connecting to a normal water supply or hot water tap, the supply pressure of water or hot water supplied from the water supply or hot water tap becomes very low. Specifically, the supply water pressure of a normal water supply is about 0.3 to 0.8 MPa, but the dynamic water pressure (release pressure) at the faucet of an actual hot water tap through a pressure reducing valve and a water heater is 0.035. About 0.040 MPa.

  On the other hand, when the conventional swirl injection valve is used, according to the experimental results, when the amount of water per nozzle is 0.3 liter / min, an empty conical spray spray with a supply water pressure lower than 0.05 MPa is used. The pattern cannot be maintained. At the same time, in such a low supply water pressure region, the thin water film does not spread sufficiently, and thus membrane breakup does not occur sufficiently. Therefore, the spray particles become large. When the particle size (particle volume) of the spray particles is large, the temperature of the water droplets of the hot water is not easily lowered even after the hot water is injected from the spiral injection valve. At this time, if the set temperature of the hot water is high, hot water droplets may be ejected, resulting in a safety problem.

  Therefore, an object of the present invention is to obtain a normal spray pattern even when the supply water pressure is about 0.035 to 0.040 MPa when the supply water amount is 0.2 to 0.3 liter / min. An object is to provide a mist injection valve capable of spraying fine mist.

  In order to solve the above problems, the present inventor attempts various improvements to the conventional simple swirl injection valve and investigates the cause of the thin water film not sufficiently spreading in the low supply water pressure region. went. As a result, it was found that a large turbulent flow occurred in the discontinuous surface portion where the inner wall surface between the swirling flow generating chamber and the injection port was bent at a low supply water pressure, and this disturbed the swirling flow generating chamber. It was found that this disturbance disturbed the empty conical water film injected from the injection port, and as a result, the membranous division was incomplete and a normal spray pattern could not be obtained. The present invention has been made based on the knowledge obtained as described above.

  That is, the mist injection valve according to the present invention includes a swirl flow generation chamber having a circular cross section, one or more inflow ports communicating with the swirl flow generation chamber in a substantially tangential direction, and one end of the swirl flow generation chamber. A mist injection valve having an opening and an injection port formed in an orifice shape coaxially with the central axis of the swirl flow generation chamber, and a bent portion of an inner wall surface from the swirl flow generation chamber to the outlet of the injection port Are all formed into a smooth curved surface.

  Thus, by forming all the curved portions of the inner wall surface from the swirl flow generation chamber to the outlet of the injection port into a smooth curved surface, generation of turbulent flow that disturbs the spiral flow inside the swirl flow generation chamber can be suppressed. Therefore, the turning force is well transmitted to the water ejected from the ejection port. Therefore, even when the incoming water pressure is low, the injected thin water film spreads well, and the turbulence of the empty cone is reduced. And even if injection pressure is low, it becomes possible to obtain fine spray.

Further, in the present invention, the cross-sectional area _{S 2} of the narrowest portion of the injection port, the ratio of the total cross-sectional area _{S 1} of all of the _{inlet, S 2: S 1 = 1} : 1.8~1: 2.4.

  By setting the area ratio, the best spray pattern can be obtained.

  As described above, according to the mist injection valve according to the present invention, all the bent portions of the inner wall surface from the swirl flow generating chamber to the outlet of the injection port are formed into a curved surface, whereby the outlet of the injection port from the swirl flow generation chamber. Until the swirl motion of water is maintained well. As a result, when the incoming water pressure (dynamic pressure) is as low as 0.035 MPa, a normal spray pattern is obtained even when the injection amount is 0.26 liter / min, and small and uniform spray particles are injected. It becomes possible to make it.

  Further, if this mist injection valve is used in a mist / sauna apparatus, a water heater having a low discharge pressure can be used. Even if the outlet pressure of the water heater is low, the spray particles are small, so the risk of burns approaching the injection port of the mist injection valve can be reduced.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of a mist injection valve according to Embodiment 1 of the present invention. 1A is a front view of the mist injection valve as viewed from the injection port side, FIG. 1B is a side view of the mist injection valve, and FIG. 1C is a sectional view thereof. FIG. 2 is a diagram illustrating a configuration of a nozzle mouth body of the mist injection valve in FIG. 1. 2A is a cross-sectional view of the nozzle mouth body, and FIG. 2B is a rear view of the nozzle mouth body.

  The mist injection valve 1 includes a hollow cylindrical nozzle body 2. The rear end 2a of the nozzle body 2 has an inlet 3 through which water or hot water (hereinafter referred to as “hot water”) flows. An inner flange 4 is formed at the front end 2 b of the nozzle body 2.

  Inside the cylinder of the nozzle body 2, a holding core 5 and a nozzle port body 6 are provided from the introduction port 3 side. The holding core 5 is composed of three parts, that is, a screwing part 7, a connecting part 8, and a closing cover part 9 from the introduction port 3 side. The threaded portion 7 is cylindrical and has a central hole 10 drilled along the central axis. A male screw 11 a is engraved on the outer side wall of the threaded portion 7. The male screw 11a is screwed with a female screw 11b engraved in the cylinder of the nozzle body 2 to fix the retaining core 5 in the cylinder of the nozzle body 2 and to fix the nozzle mouth body 6 inside. The flange 4 is pressed from the inside.

  The connecting portion 8 is a constricted portion that connects the screwing portion 7 and the closing lid portion 9. The connecting portion 8 has a hollow central axis portion, and is composed of two members on the left and right along the central axis. Between the two left and right members is a horizontal hole 12, and warm water flowing from the introduction port 3 passes through the central hole 10 and flows from the horizontal hole 12 to the closed wall 9 and the inner wall of the nozzle body 2. 13 can flow into.

  The closing lid portion 9 has a cylindrical block shape and is in pressure contact with the nozzle mouth body 6.

  The outer peripheral surface of the nozzle mouth body 6 is formed in a stepped cylindrical shape having a large diameter portion 6a and a small diameter portion 6b. The small-diameter portion 6b is fitted to the inner flange 4, and the step portion 6c between the large-diameter portion 6a and the small-diameter portion 6b is in contact with the inside of the inner flange 4 and is fixed in a state of being pressed by the retaining core 5. Yes. The nozzle body 6 has a jet port 16 perforated along the central axis.

  A swirl flow generating chamber 14 having a circular cross section is formed inside the large diameter portion 6a. The swirl flow generating chamber 14 is configured by the lid portion 9 closing a circular concave portion 14a formed on the end face side of the large diameter portion 6a.

  In addition, two inlets 15, 15 communicating with the rotary flow generation chamber 14 in a substantially tangential direction are formed on the end face side of the large diameter portion 6 a. The inflow ports 15 and 15 are configured by closing the inflow grooves 15 a and 15 a formed on the end face side of the large diameter portion 6 a of the nozzle mouth body 6 by the closing portion 9.

  An injection port 16 is formed in an orifice shape penetrating from the swirl flow generation chamber 14 through the small diameter portion 6b. The injection port 16 gradually decreases in diameter from the swirl flow generation chamber 14 side to the center of the injection port 16, the diameter of the center of the injection port 16 is the smallest, and the diameter gradually increases from the center of the injection port 16 to the outlet of the injection port 16. It is formed in a channel shape. Further, the bent portions 20, 21, and 22 of the inner wall surface from the swirl flow generation chamber 14 to the outlet of the injection port 16 are all formed into smooth curved surfaces.

Further, the flow area of the minimum diameter portion at the center of the injection port 16 (hereinafter referred to as “injection flow area”) is S ₂ , and the sum of the flow area of each inlet 15 (hereinafter referred to as “inflow flow area”). When S ₁ is S ₁ , the area ratio is S ₂ : S ₁ = 1: 1.8 to 1: 2.4.

  The operation of the mist injection valve of the present embodiment having the above configuration will be described below. First, water or warm water (hereinafter collectively referred to as “water”) flows into the introduction port 3 from a water tap or a hot water tap. The water that has flowed into the introduction port 3 flows from the central hole 10 of the retaining core 10 through the lateral hole 12 to the inflow path 13. Then, it flows into the swirl flow generation chamber 14 from the two inlets 15 and 15. Since the inflow port 15 is opened toward the tangential direction of the swirl flow generation chamber 14, the water flowing into the swirl flow generation chamber 14 swirls along the wall surface of the swirl flow generation chamber 14 to form a vortex flow. And it advances to the axial direction of the nozzle mouth body 6 while turning, and is injected from the tip of the mist injection valve 1 through the injection port 16. The jetted water is jetted while having a turning speed and an axial speed, and forms a hollow cone-shaped thin water film. The thin water film is turned into fine particles by film splitting and becomes mist. Thereby, mist is sprayed.

  Here, since the bent portions 20, 21, and 22 of the inner wall surface from the swirl flow generating chamber 14 to the outlet of the injection port 16 are all formed in smooth curved surfaces, turbulent flow is unlikely to occur. Accordingly, the water flow that moves while swirling from the swirling flow generation chamber 14 to the outlet of the injection port 16 is ejected from the injection port 16 without causing a large turbulent flow, and thus the loss of swirl force is small. Therefore, even when the supply water pressure from the inlet 15 is low, such as a hot water tap, the swirling motion of water is maintained up to the outlet of the injection port 16, and the water injected from the injection port 16 is a normal thin water film having an empty cone shape. Form. Accordingly, a normal spray pattern can be obtained, and a uniform mist with a small particle size can be sprayed by film-like splitting.

Finally, a description will be given of results of experiments on the relationship between the area ratio and the spray pattern of the injector flow area S ₂ and the inflow passage area S _1.

  As for the dimensions of the mist injection valve used, the minimum diameter of the injection port 16 is 1.4 mmφ, the length of the injection port 16 is 2 mm, the diameter of the swirling flow generation chamber 14 is 4.78 mmφ, and the height of the swirling flow generation chamber 14 is It was 2 mm.

3 to 10 are diagrams showing changes in the spray pattern when the area ratio R = S ₂ : S ₁ between the injection flow path area S ₂ and the inflow flow path area S ₁ is changed. In any case, the supply water pressure of the water supplied to the inlet 3 is 0.04 MPa.

  When the supply water pressure is 0.04 MPa and the area ratio R = 1: 2, a normal empty conical thin water film is formed as shown in FIG. 3, and a good spray pattern is obtained. Therefore, Table 1 shows the experimental results in which the area ratio R is changed up and down with the area ratio R = 1: 2.

  From the above experimental results, the allowable range of the area ratio R when the supply water pressure is 0.04 MPa is approximately R = 1.1.17 to 1: 2.65, and the optimum value of the area ratio R is approximately R = 1: 1. It is concluded that .6 to 1: 2.4.

  When the mist injection valve 1 is actually connected to a hot-water tap and used, the water supply pressure is about 0.3 to 0.8 MPa. The dynamic water pressure from the hot water storage type water heater through a pressure reducing valve such as a hot water tap is about 0.04 MPa. Therefore, as a use condition of the mist injection valve 1, the supply water pressure to the water inlet 3 may be set in a range of 0.035 to 0.05 MPa. Then, referring to the experimental results, it can be concluded that the optimum value of the area ratio R is R = 1: 1.8 to 1: 2.4.

It is a figure showing the structure of the mist injection valve which concerns on Example 1 of this invention. It is a figure showing the structure of the nozzle mouth body of the mist injection valve of FIG. Injection passage area _{S 2:} inflow passage area _S 1 = 1: 2, a diagram showing the spray pattern for supply water pressure 0.04 MPa. Injection passage area _{S 2:} inflow passage area _S 1 = 1: 1.17, a diagram showing the spray pattern for supply water pressure 0.04 MPa. Injection passage area _{S 2:} inflow passage area _S 1 = 1: 1.55, a diagram showing the spray pattern for supply water pressure 0.04 MPa. Injection passage area _{S 2:} inflow passage area _S 1 = 1: 2.33, a diagram showing the spray pattern for supply water pressure 0.04 MPa. Injection passage area _{S 2:} inflow passage area _S 1 = 1: 2.49, a diagram showing the spray pattern for supply water pressure 0.04 MPa. Injection passage area _{S 2:} inflow passage area _S 1 = 1: 2.65, a diagram showing the spray pattern for supply water pressure 0.04 MPa. It is a schematic cross section of the main pressure type atomization valve. It is an operation principle diagram of a typical spiral injection valve (simple spiral injection valve). It is sectional drawing of the simple spiral injection valve of patent document 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mist injection valve 2 Nozzle body 2a Rear end part 2b Front end part 3 Introduction port 4 Inner flange 5 Pressing core 6 Nozzle port body 6a Large diameter part 6b Small diameter part 6c Step part 7 Screwing part 8 Connection part 9 Closing part DESCRIPTION OF SYMBOLS 10 Center hole 11a Male screw 11b Female screw 12 Horizontal hole 13 Inflow path 14 Swirling flow generation chamber 14a Circular recessed part 15 Inlet 15a Inlet groove 16 Injection port 20,21,22 Curved part

Claims (2)

A swirl flow generation chamber having a circular cross section;
One or more inlets communicating in a substantially tangential direction with the swirl flow generating chamber;
An opening formed at one end of the swirl flow generation chamber, and formed in an orifice shape coaxially with the central axis of the swirl flow generation chamber;
In a mist injection valve equipped with
A mist injection valve characterized in that all bent portions of the inner wall surface from the swirl flow generating chamber to the outlet of the injection port are formed into a smooth curved surface. Wherein the cross-sectional area _{S 2} of the narrowest portion of the injection port, the ratio of the total cross-sectional area _{S 1} of all of the _{inlet, S 2: S 1 = 1} : 1.8~1: it is 2.4 The mist injection valve according to claim 1.

Images