spray nozzle

Abstract

To provide a spray nozzle that can spray a gas-liquid mixture over a wide area even in small amounts.SOLUTION: A spray nozzle 100 comprises: an air introduction part 17 which is located on a base end side to which a liquid supply pipe 70 is connected, and introduces air into a liquid; an introduction passage 14C which communicates with the air introduction part 17 and an exterior space, and introduces external air into the air introduction part 17; a nozzle holder 10 in which a mixing chamber 19 for mixing the liquid and the external air is formed; a tip spray plate 50 which is attached to a tip of the nozzle holder 10, and in which a slit 56 is formed; a nozzle core 30 having a guide channel 37 which guides a gas-liquid mixture toward the slit 56; and an orifice plate 20 which is accommodated on the base end side of the nozzle holder 10, and has an erection injection part 22 in which a pin hole 23 for injecting the liquid from the liquid supply pipe 70 to the air introduction part 17 is formed. The guide channel 37 is provided unsymmetrically when a diameter of a base plate 32 orthogonal to a center line of a projection 36 for fitting between the projections 36 for fitting is so made as to a symmetrical line.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a spray nozzle for spraying a gas-liquid mixture, which is a mixture of a liquid and a gas.

Background Art

[0002] As a spray nozzle for spraying a gas-liquid mixture, which is a mixture of a liquid and a gas, a nozzle having a configuration as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2022-014191) is known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By using the spray nozzle disclosed in Patent Document 1, it has become possible to spray the gas-liquid mixture over a wider range even when spraying the gas-liquid mixture at a low flow rate and low pressure as compared with conventional spray nozzles. However, further improvement in the performance of the spray nozzle is desired.

Means for Solving the Problems

[0005] Therefore, the present invention has been made to solve the above problems, and an object of the present invention is to provide a spray nozzle capable of reliably spraying a gas-liquid mixture even when spraying the gas-liquid mixture with a small amount of the gas-liquid mixture.

[0008] liquidA spray nozzle for spraying a gas-liquid mixture of body and air, comprising: a nozzle holder positioned at the base end, which is the connection side with the liquid supply pipe that supplies the liquid, having an air introduction section for introducing the air into the liquid, an introduction passage communicating with the air introduction section and the external space for introducing external air into the air introduction section, and a mixing chamber for mixing the liquid taken in by the air introduction section with the external air to generate the gas-liquid mixture; a front spray plate mounted on the tip side of the nozzle holder, having a slit formed therein which is the nozzle opening for spraying the gas-liquid mixture supplied from the mixing chamber; and between the nozzle holder and the front spray plate The nozzle holder comprises a circular substrate in plan view disposed on the surface, a guide channel that penetrates the substrate in the thickness direction and guides the gas-liquid mixture supplied from the mixing chamber toward the slit, a nozzle core with two fitting protrusions formed thereon that rise from the upper surface of the substrate and fit into the nozzle plate with a recessed and recessed design, and an orifice plate housed on the base end side of the nozzle holder and having a pinhole formed therein for injecting the liquid supplied from the liquid supply pipe into the air inlet, wherein the guide channel is asymmetrical between the opposing surfaces of each fitting protrusion when the diameter of the substrate perpendicular to the center line of each fitting protrusion is used as the line of symmetry. and at one location on the side of one of the fitting projections The nozzle core is provided with an upright piece that rises from the upper surface of the substrate and is lower than the height of the nozzle blade. The inner upright surface of the fitting projection on the other side, which is not provided with the aforementioned guide channel, is integrated with the other side. It is characterized by being provided 。

[0009] As a result, reliable spraying is possible even when spraying low volumes of gas-liquid mixtures. Therefore, it becomes possible to significantly reduce the labor burden during spraying operations involving gas-liquid mixtures, such as pesticide application. [Effects of the Invention]

[0010] By adopting the spray nozzle configuration of the present invention, it is possible to spray a wide area even when spraying a gas-liquid mixture at low volume and low pressure, thereby significantly reducing the labor burden in spraying gas-liquid mixtures, such as in pesticide application. [Brief explanation of the drawing]

[0011] [Figure 1] This is an exploded view of the spray nozzle in this embodiment. [Figure 2] This is a front view of the spray nozzle in this embodiment. [Figure 3] This is a plan view of the spray nozzle in this embodiment. [Figure 4] This is a cross-sectional view along line IV-IV in Figure 3. [Figure 5] Figure 4 is an enlarged view of the base. [Figure 6] This is a magnified plan view of the nozzle core. [Figure 7] This is a cross-sectional view along the line VII-VII in Figure 6. [Figure 8] This is a cross-sectional view along the line VIII-VIII in Figure 6. [Figure 9] This is an enlarged plan view of the pre-spray plate. [Figure 10] This is a cross-sectional view along line XX in Figure 9. [Figure 11] This is a cross-sectional view along the line XI-XI in Figure 9. [Figure 12] This is an explanatory diagram showing the internal structure of the nozzle core and the nozzle tip. [Figure 13] This is a plan view showing a modified example of the nozzle core. [Figure 14] This is a plan view showing a modified example of the nozzle core. [Figure 15] This is a plan view showing a modified example of the nozzle core. [Modes for carrying out the invention]

[0012] Hereinafter, embodiments of the spray nozzle 100 according to the present invention will be specifically described with reference to the drawings. As shown in Figures 1 to 3, the spray nozzle 100 in this embodiment comprises a nozzle holder 10, an orifice plate 20, a nozzle core 30, an O-ring 40 as a sealing member, a spray plate 50, and a nozzle cap 60.

[0013] The nozzle holder 10 has a main body portion 11, a first rib 12, a second rib 13, a base portion 14, and a male screw portion 15. The main body portion 11 is formed as a cylindrical body having an internal space penetrating in the height direction. On the outer peripheral surface of the main body portion 11, a first rib 12 is disposed which stands upright in a direction orthogonal to the radially outer direction of the main body portion 11 and along the height direction of the main body portion 11. This first rib 12 is disposed at a plurality of locations at a required interval along the circumferential direction of the outer peripheral surface of the main body portion 11. Also, at an intermediate position in the height direction of the first rib 12, a second rib 13 is disposed which stands upright in a direction orthogonal to the radially outer direction from the outer peripheral surface of the main body portion 11 and along the circumferential direction of the main body portion 11. By providing such first rib 12 and second rib 13 on the main body portion 11, the main body portion 11 can be given sufficient strength and can be lightened.

[0014] A base portion 14 is formed on the proximal end side (the connection side with the liquid supply pipe 70) of the main body portion 11. The base portion 14 has a flange portion 14A, a small-diameter portion 14B, an introduction path 14C, a connection portion 14D, and an inner space 14E of the base portion. The flange portion 14A is for holding a connecting body 80 that connects the liquid supply pipe 70 to the nozzle holder 10. The small-diameter portion 14B is a portion formed to have a smaller diameter than the flange portion 14A and is integrated with the lower end portion of the first rib 12. Also, on the outer peripheral surface of the small-diameter portion 14B, an introduction path 14C for introducing external air into an air introduction portion 17 (described later) formed inside the main body portion 11 is formed. The introduction path 14C in the present embodiment extends in a direction orthogonal to the radially outer direction from the central axis of the main body portion 11 at two locations spaced 180 degrees apart around the central axis of the main body portion 11, and communicates the external space and the air introduction portion 17.

[0015] Also, on the bottom side of the base portion 14, a connection portion 14D is formed which is formed to have a smaller diameter dimension than the flange portion 14A and to which the liquid supply pipe 70 is connected. Also, a concave inner space 14E of the base portion is formed on the bottom surface of the connection portion 14D. The orifice plate 20 (described later) is accommodated in the inner space 14E of the base portion.

[0016] The tip side (upper end side) of the main body 11 has a cylindrical shape with a male threaded portion 15 having screw threads on its outer circumference. Inside the male threaded portion 15, an internal space 15A is formed, and on the outer circumference surface of the internal space 15A (the inner circumference surface of the male threaded portion 15), there are two positioning protrusions 16 that are evenly spaced in the circumferential direction and protrude toward the inside of the internal space 15A (the central axis of the male threaded portion 15 (not shown)).

[0017] As shown in Figures 4 and 5, the main body 11 has a flow path space for the liquid supplied from the liquid supply pipe 70 to pass through. This flow path space is formed in the following order from the base end side of the main body 11: the base inner space 14E, the air introduction section 17, the flow path 18, the enlarged diameter flow path 19A, and the male screw section inner space 15A. The base inner space 14E communicates with the internal space of the liquid supply pipe 70, and the enlarged diameter flow path 19A communicates with the male screw section inner space 15A. In this embodiment, the enlarged diameter flow path 19A and the male screw section inner space 15A, which are continuous in the flow path direction, form a mixing chamber 19.

[0018] The air introduction section 17, which communicates with the inner space 14E of the base section, has an introduction path communication space 17A in which the communication section 14F of the introduction path 14C is formed, and a reduced diameter section 17B provided downstream of the introduction path communication space 17A, which gradually narrows in diameter as it proceeds in the flow direction. The height position of the introduction path communication space 17A is formed to be the same as the height position of the communication section 14F, which is the opening in the introduction path communication space 17A of the introduction path 14C, and the inner diameter dimension of the introduction path communication space 17A is formed to be the same dimension (cylindrical) in the height direction. The reduced diameter section 17B is intended to ensure that even if the central axis of the path of water injected into the introduction path communication space 17A does not coincide with the central axis of the main body section 11, the water is reliably guided into the flow path 18 together with the external air taken in from the introduction path 14C.

[0019] The orifice plate 20 housed in the inner space 14E of the base portion has a circular substrate portion 21 in plan view, an upright injection portion 22 that rises from the central part of the substrate portion 21 to the upper surface (front side) of the substrate portion 21, and a pinhole 23 formed on the upper surface (front side) of the upright injection portion 22. By housing such an orifice plate 20 in a fitted state in the inner space 14E of the base portion, which is the connection part with the liquid supply pipe 70, the flow velocity of the liquid supplied from the liquid supply pipe 70 is increased in the inner space 14E of the base portion, and the liquid can be injected at high speed with pinpoint accuracy into the air introduction portion 17 which communicates with the inner space 14E of the base portion.

[0020] Furthermore, in this embodiment, the height position of the opening surface of the pinhole 23 of the upright spray section 22 is the same height position as the height position of the central axis of the introduction passage 14C (communication section 14F). Also, as mentioned above, the introduction passage 14C is arranged at two locations at equal intervals in the circumferential direction of the base section 14 (nozzle holder 10, main body section 11) when the spray nozzle 100 is viewed from above.

[0021] The cylindrical channel 18 connected to the air intake section 17 has the same inner diameter as the inner diameter of the narrowest part of the reduced diameter section 17B. This channel 18 prevents backflow of external air taken in from the intake passage 14C, ensuring that sufficient external air is supplied to the connected widened channel 19A (mixing chamber 19). It also prevents backflow of the gas-liquid mixture from the widened channel 19A.

[0022] The expanding channel 19A is formed in the shape of an inverted frustoconical cone, gradually expanding in diameter as it flows downward, and is continuous with the internal space 15A of the male screw portion. The diameter of the narrowest part (starting end) of the expanding channel 19A is formed to be larger than the inner diameter of the channel 18. At the start of spraying of the gas-liquid mixture, the water and outside air that have passed through the channel 18 pass through the mixing chamber 19, collide with the lower surface of the nozzle core 30 and bounce back, mixing the water and outside air, and temporarily storing in the mixing chamber 19. Even after the mixing chamber 19 is filled with water and outside air, water and outside air are still supplied from the channel 18, and the newly supplied water and outside air collide with the gas-liquid mixture stored in the mixing chamber 19, causing further mixing. In this way, a gas-liquid mixture in which water and outside air are sufficiently mixed can be produced.

[0023] Furthermore, as in this embodiment, by storing the gas-liquid mixture with finely atomized bubbles in the internal space 15A of the male screw portion, which is directly in front of the nozzle core 30, the flow velocity of the gas-liquid mixture supplied to the nozzle nozzle 50 through the guide channel 37 of the nozzle core 30 can be increased, even when spraying at low volume and low pressure.

[0024] As shown in Figures 6 to 8, the nozzle core 30 in this embodiment has a core body substrate 32, a positioning recess 34, a fitting projection 36, a guide channel 37, and an upright piece 38. The substrate 32 is formed in a circular shape in plan view with a diameter larger than the opening diameter of the internal space 15A of the male screw portion. The positioning recess 34 is formed on the lower surface of the substrate 32 to match the position of the positioning projection 16, so that the positioning projection 16 and the positioning recess 34 fit together. The mounting direction of the nozzle core 30 to the nozzle holder 10 (upper surface of the male screw portion 15) can be determined by the arrangement of the positioning projection 16.

[0025] The fitting projection 36 is for fitting onto the nozzle plate 50 to hold the nozzle plate 50. In this embodiment, the fitting projection 36 is erected at two locations on the diameter line of the substrate 32, spaced apart by a required interval. The fitting projection 36 is formed in a parabolic shape, gradually increasing in protrusion height from the outer edge of the substrate 32 toward the center point of the substrate 32, and is formed within a required diameter range from the outer edge of the substrate 32. The inner upright surface 36A, which is the opposite surface of the fitting projection 36, is erected perpendicular to the upper surface of the substrate 32, and its central portion is formed as an arcuate surface in plan view.

[0026] As shown in Figures 1, 4, 6, and 7, a guide channel 37 is provided in the planar region sandwiched between the inner upright surfaces 36A of the two fitting protrusions 36. In this embodiment, the guide channel 37 is formed by a through hole that penetrates the substrate 32 in the thickness direction. When the nozzle core 30 is viewed from above, the guide channel 37 is positioned on the line of the first straight line L1 (dashed line in Figures 1, 3, and 6), which is the center line in the planar extension direction of the fitting protrusions 36, and is also positioned at one location close to one of the fitting protrusions 36. In other words, in this embodiment, the guide channel 37 is asymmetrically positioned between the inner upright surfaces 36A, which are the opposing surfaces of the two fitting protrusions 36, with respect to the diameter D of the substrate 32 perpendicular to the first straight line L1 in the horizontal plane as the line of symmetry. In this specification, "asymmetrically positioned" means that at least one of the position of arrangement and the cross-sectional area of ​​the channel are asymmetrical.

[0027] Here, if the cross-sectional area of ​​the guide channel 37 in this embodiment is the same as the cross-sectional area of ​​the guide channel 37 in the prior art, then the cross-sectional area of ​​the guide channel 37 in this embodiment will be half the cross-sectional area of ​​the guide channel 37 in the prior art. This makes it possible to significantly increase the flow velocity of the gas-liquid mixture supplied to the nozzle 50.

[0028] Furthermore, the position of the guide channel 37 in this embodiment is parallel to (on the same straight line as) the second straight line L2 (dotted line in Figures 1 and 3) that connects the communication sections 14F, which are the openings of the introduction channels 14C on the side of the introduction channel communication space 17A. Experiments by the applicant have shown that by adopting this arrangement of the guide channel 37 and the introduction channels 14C (communication sections 14F), the spray width from the slit 56 can be widened.

[0029] Furthermore, as shown in Figures 4 and 6, the guide channel 37 in this embodiment is formed with a smaller opening on the upper side (tip side) than the opening on the lower side (base side) of the substrate 32 in order to further increase the flow velocity of the gas-liquid mixture supplied to the nozzle plate 50. More specifically, the guide channel 37 in this embodiment is formed in a shape (isospherical trapezoidal cross-section) in which the cross-sectional area of ​​the channel gradually decreases as it moves from the base side to the tip side. Note that although the guide channel 37 is formed in an isospherical trapezoidal cross-section here, the guide channel 37 is not limited to an isospherical trapezoidal cross-section.

[0030] Furthermore, in this embodiment, the nozzle core 30 has an upright piece 38 erected on the upper surface of the substrate 32. In this embodiment, the upright piece 38 is integrated with the inner upright surface 36A of the fitting projection 36 on the side where the guide channel 37 is not provided. In this embodiment, the height position of the upper end surface of the upright piece 38 is formed lower than the height position of the inner upright surface 36A at the portion where it is integrated with the inner upright surface 36A, but the height of the upright piece 38 only needs to be formed lower than the height position of the nozzle nozzle 50. In this embodiment, the upright piece 38 is erected at a position on the line of the first straight line L1, similar to the guide channel 37, and is arranged asymmetrically on the upper surface of the substrate 32 when the diameter D of the substrate 32 that is perpendicular to the first straight line L1 in the horizontal plane is used as the line of symmetry.

[0031] The nozzle core 30 formed in this manner is mounted on the upper surface of the male threaded portion 15 in a sealed state by an O-ring 40 acting as a sealing member that contacts the upper surface of the male threaded portion 15 and the outer peripheral edge of the nozzle core 30, respectively, and by a positioning projection 16 and a positioning recess 34. The arcuate surface portion in plan view is a relief portion for the molding pin when forming the guide channel 37.

[0032] A pre-spray plate 50, as shown in Figures 9 to 11, is placed on top of the nozzle core 30. In this embodiment, the pre-spray plate 50 has a base portion 52 formed in the shape of a substrate, with a constricted portion 54, a slit 56, and a thin-walled portion 58 formed thereon. The constricted portion 54 is formed in a convex shape that protrudes upward (towards the tip of the spray nozzle 100) than other planar portions of the base portion 52 by drawing or the like on the diameter line of the base portion 52 (on the same straight line as the arrangement direction of the guide channel 37). In this embodiment, the fitting projection 36 of the nozzle core 30 can enter the inner surface of the constricted portion 54. Furthermore, as shown in Figure 10, in this embodiment, the shape of the rising portion 54A from the base portion 52 is formed to conform to the outer surface shape of the fitting projection 36 of the nozzle core 30, and the shapes of the constricted portion 54 and the fitting projection 36 are molded so that they fit into the inner surface of the constricted portion 54.

[0033] A slit 56, which is the nozzle for spraying the gas-liquid mixture, is formed in the center of the longitudinal direction (direction of the first straight line L1) of the throttling section 54, arranged perpendicular to the longitudinal direction of the throttling section 54. Furthermore, the required area of ​​the throttling section 54, including the part where the slit 56 is formed, is formed as a thin-walled section 58, which is thinner than the thickness of the other parts of the throttling section 54. By forming such a thin-walled section 58, the thickness of the plate at the opening edge of the slit 56 is reduced, which reduces the frequency of droplet formation of the gas-liquid mixture in this area. This prevents droplets from dripping from the opening edge of the slit 56, and even if droplets do form, they detach from the opening edge of the slit 56 at a small droplet stage, thus reducing uneven spraying.

[0034] Furthermore, as shown in Figure 10, the thin-walled portion 58 in this embodiment is formed as a curved surface that is concave (has an arc shape when viewed from the front) toward the tip side, and the slit 56 is provided at the bottom of the curved surface so as to cross the constricted portion 54 in a direction perpendicular to it. As a result, the thinnest part of the nozzle plate 50 is at the opening edge of the slit 56. It is preferable that such a thin-walled portion 58 is formed by wire electrical discharge machining. Forming the thin-walled portion 58 by wire electrical discharge machining is advantageous because it eliminates the generation of burrs at the opening edge of the slit 56, prevents a reduction in the spray range of the gas-liquid mixture, and further reduces droplet formation.

[0035] Figure 12 is a cross-sectional view of the main part showing the nozzle core 30 with the nozzle plate 50 fitted into it. When the throttled portion 54 of the nozzle plate 50 is inserted (fitted) into the fitting projection 36 of the nozzle core 30, a space is formed in the area surrounded by the base plate 32, the inner upright surface 36A (fitting projection 36), and the throttled portion 54. This space is used as a buffer space 39 for storing a predetermined amount of gas-liquid mixture in order to increase the flow velocity of the gas-liquid mixture sprayed from the slit 56. The buffer space 39 between the nozzle plate 50 and the nozzle core 30 prevents the gas-liquid mixture supplied from the guide channel 37 from being sprayed directly from the slit 56. By storing a predetermined volume of gas-liquid mixture in the buffer space 39 in this way, the force of the gas-liquid mixture sprayed from the slit 56 can be increased, and further mixing of the gas-liquid mixture can also be achieved.

[0036] As shown in Figures 1 and 4, the nozzle cap 60 is a cylindrical body with a narrow-diameter portion 62 at its tip, and a female thread 64 is formed on the inner circumferential surface of the nozzle cap 60 that screws onto the male thread portion 15. By screwing the male thread portion 15 onto the female thread 64 of the nozzle cap 60, the narrow-diameter portion 62 presses the base portion 52 of the nozzle tip plate 50 against the upper surface of the male thread portion 15, causing the O-ring 40 to elastically deform and allowing the nozzle core 30 and nozzle tip plate 50 to be fixedly held in a sealed state against the male thread portion 15.

[0037] As shown in Figures 2 to 4, the connecting body 80 is a cylindrical body with a female threaded portion 82 formed on its inner circumference and a non-slip protrusion 84 formed on its outer circumference. By screwing the male thread 74 formed on the connecting end 72 of the liquid supply pipe 70, which is connected to the connecting portion 14D of the base portion 14, into the female threaded portion 82, the nozzle holder 10 and the liquid supply pipe 70 can be connected in a way that prevents them from coming loose. Even when the connecting body 80 is screwed onto the nozzle holder 10, the inner diameter of the upper end portion 86 of the connecting body 80 is formed to be slightly larger than the outer diameter of the base portion 14, so that the introduction passage 14C is not blocked and foreign matter can not be sucked in from the introduction passage 14C.

[0038] The structure of the spray nozzle 100 in this embodiment has been described above. Next, the mechanism for spraying a gas-liquid mixture, in which water is supplied as liquid and external air as gas to the spray nozzle 100 in this embodiment, will be described. Water supplied from tap water or the like is supplied to the nozzle holder 10 from the liquid supply pipe 70. The water supplied to the nozzle holder 10 has its flow path cross-sectional area reduced by the upright injection section 22 of the orifice plate 20, and passes through the pinhole 23 formed in the upright injection section 22, thereby increasing the flow velocity of the water passing through the nozzle holder 10 and lowering the pressure in the surrounding space through which the water passes.

[0039] As shown in Figures 4 and 5, the height of the opening surface of the pinhole 23 is at the same height as the communication section 14F, which is the opening of the introduction passage communication space 17A of the introduction passage 14C that takes in outside air. Furthermore, since the communication section 14F is arranged opposite the base section 14 (nozzle holder 10, main body section 11) when viewed from above, the horizontal velocity component of the outside air taken in from the introduction passage 14C (communication section 14F) is canceled out in the introduction passage communication space 17A. As a result, the outside air taken into the introduction passage communication space 17A by the depressurization effect of the water sprayed from the pinhole 23 is efficiently taken in along with the water into the reduced diameter section 17B and the flow path 18, and a sufficient amount of outside air can be taken in relative to the amount of water supplied.

[0040] In this way, the water and outside air taken into the nozzle holder 10 are reliably supplied to the enlarged diameter channel 19A, which is part of the mixing chamber 19, without backflow through the narrowed diameter section 17B and the cylindrical channel 18. The water and outside air taken in through the introduction passage communication space 17A are sent to the mixing chamber 19 with increased flow velocity through the narrowed diameter section 17B and the channel 18. The gas-liquid mixture sent to the enlarged diameter channel 19A collides with the nozzle core 30 housed in the male screw section internal space 15A, which is part of the mixing chamber 19, and is mixed with the outside air. The gas-liquid mixture is then temporarily stored in the male screw section internal space 15A.

[0041] Furthermore, at the connection point between the flow path 18 and the enlarged flow path 19A, the inner diameter of the enlarged flow path 19A is formed to be larger, and the enlarged flow path 19A is formed in a shape where the inner diameter gradually increases toward the downstream side. In the internal space of the enlarged flow path 19A formed in this shape, the water and external air supplied from the flow path 18 collide with the already stored gas-liquid mixture, and mixing also occurs due to rapid expansion losses. When water and external air are supplied from the flow path 18, the gas-liquid mixture in the mixing chamber 19 sequentially flows from the guide flow path 37 of the nozzle core 30 into the buffer space 39 formed inside the throttling section 54 of the nozzle tip 50.

[0042] When the buffer space 39 is filled with the gas-liquid mixture, the mixture is sprayed in a fan shape from the slit 56. In this embodiment, the gas-liquid mixture sprayed from the spray nozzle 100 is temporarily stored in the buffer space 39 as described above, and then sprayed from the slit 56 under increased pressure. In other words, the well-mixed gas-liquid mixture can be sprayed vigorously in a fan shape from the slit 56.

[0043] As described above, by using the spray nozzle 100 in this embodiment, the volume of bubbles per unit volume of the sprayed gas-liquid mixture can be significantly improved compared to conventional methods, thus drastically reducing the amount of water used when spraying chemicals. In other words, the gas-liquid mixture can be sprayed over a wide area with a small amount of water using a single-head nozzle structure, greatly improving work efficiency. Furthermore, this is particularly advantageous when spraying herbicides, as the particle size of the sprayed gas-liquid mixture does not become excessively small, thus preventing unintended scattering due to wind during spraying.

[0044] Furthermore, since a thin-walled portion 58 is formed in the required area including the slit 56, even when spraying a gas-liquid mixture, the amount of particles of the gas-liquid mixture that accumulate at the opening edge of the slit 56 can be minimized. This is advantageous because it prevents droplets from dripping from the slit 56 and improves the uniformity of the spray density of the gas-liquid mixture in the spraying area.

[0045] The spray nozzle 100 according to the present invention has been described above based on embodiments, but the configuration of the spray nozzle 100 according to the present invention is not limited to the embodiments described above. For example, in the spray nozzle 100 in the embodiments described above, a mixture of external air and water is given as an example of a gas-liquid mixture, but the gas-liquid mixture is not limited to a mixture of external air and water, and can also be a gas-liquid mixture of external air and a herbicide, or a gas-liquid mixture of known gases and liquids.

[0046] Furthermore, in this embodiment, the nozzle core 30 is provided with one guide channel 37 and one upright piece 38, but the present invention is not limited to the above form, and the guide channel 37 and upright piece 38 can each be provided with multiple locations. That is, the guide channel 37 and the upright piece 38 should each be provided asymmetrically when the diameter D of the substrate 32, which is perpendicular to the first straight line L1 which is the center line of the fitting projection 36 on the upper surface of the substrate 32, is used as the line of symmetry.

[0047] In this embodiment, the upright piece 38 is described as being integrated with the inner upright surface 36A of the fitting projection 36 on the side where the guide channel 37 is not provided, but it is not limited to this form. The upright piece 38 may be integrated with the fitting projection 36 at a location other than the inner upright surface 36A of the fitting projection 36. Alternatively, the upright piece 38 may be formed separately from the inner upright surface 36A of the fitting projection 36. Furthermore, while it is preferable for the upright piece 38 to be erected at a position close to the inner upright surface 36A of the fitting projection 36, it can also be erected at a position away from the fitting projection 36, rather than within the planar region sandwiched between the inner upright surfaces 36A of two opposing fitting projections 36.

[0048] Furthermore, as shown in Figure 13, a configuration in which the upright piece 38 is omitted from the nozzle core 30 can also be adopted. That is, a configuration in which the nozzle core 30 is provided with a guide channel 37 and two fitting protrusions 36, which are provided only in one region separated by the first straight line L1 on the upper surface of the substrate 32.

[0049] Furthermore, as shown in Figure 14, a configuration in which an upright piece 38 is added to the nozzle core 30 in the prior art Patent Document 1 can also be adopted. In this case, the guide channel 37 is arranged symmetrically on the upper surface of the substrate 32, with respect to the diameter D of the substrate 32 perpendicular to the first straight line L1, which is the center line of the fitting projection 36. Preferably, the upright piece 38 is erected at an outer position of the planar region defined by connecting both ends of the inner upright surface 36A of the fitting projection 36 with a line parallel to the first straight line L1. Also, the upright piece 38 is arranged asymmetrically on the upper surface of the substrate 32, with respect to the diameter D of the substrate 32 perpendicular to the first straight line L1. And the upright piece 38 is also arranged only in the other region separated by the first straight line L1 on the upper surface of the substrate 32.

[0050] Furthermore, when integrating the upright piece 38 with the fitting projection 36, it is also possible to adopt a form in which the upright piece 38 is shaped to conform to the planar shape of the fitting projection 36, as shown in Figure 15, and integrated with the fitting projection 36. In this case, the part indicated by hatching in Figure 15 corresponds to the upright piece 38. In other words, in this modified example, the fitting projection 36 is formed such that the planar extension length of the fitting projection 36 differs when the diameter D of the substrate 32 perpendicular to the first straight line L1 is used as the line of symmetry (i.e., the planar shape of the fitting projection 36 is asymmetrical when the diameter D of the substrate 32 perpendicular to the first straight line L1 is used as the line of symmetry).

[0051] Furthermore, although this embodiment describes a single-head spray nozzle 100, the spray nozzle 100 according to the present invention can also be applied to each of the multi-head nozzles of a chemical spraying vehicle.

[0052] Furthermore, it is also possible to adopt a configuration that appropriately combines various modifications of the embodiments described above. [Explanation of Symbols]

[0053] 10 Nozzle holders 11 Main body, 12 First rib, 13 Second rib, 14 Base section, 14A Flange section, 14B Small diameter section, 14C Inlet path, 14D Connecting section, 14E Inner space of base section, 14F Connecting section, 15 Male threaded portion, 15A Internal space of male threaded portion, 16 Positioning protrusion, 17 Air inlet section, 17A Inlet path communication space, 17B Diameter reduction section, 18 channels, 19 Mixing chamber, 19A expanded diameter channel, 20 Orifice Plates 21 Substrate section, 22 Upright spray section, 23 Pinhole, 30 nozzle cores 32 substrate, 34 positioning recess, 36 mating projection, 36A inner upright surface, 37 Guide channel, 38 Erecting piece, 39 Buffer space, 40 O-rings (sealing components) 50 Spray plate 52 Base, 54 Constricted section, 54A Rising section, 56 Slit, 58 Thin-walled section, 60 Nozzle Caps 62 Thin diameter section, 64 Female thread, 70 Liquid supply pipe 72 connecting end, 74 male thread, 80 Concatenation 82 Female thread portion, 84 Protruding portion, 86 Upper end portion, 100 spray nozzles L1 is the first straight line, L2 is the second straight line, and D is the diameter (of the substrate).

Claims

[Claim 1] A spray nozzle for spraying a liquid-air mixture, A nozzle holder is provided, which is located on the base end side that connects to the liquid supply pipe that supplies the liquid, and has an air introduction section for introducing the air into the liquid, an introduction passage that communicates with the air introduction section and the external space for introducing external air into the air introduction section, and a mixing chamber that mixes the liquid taken in by the air introduction section with the external air to generate the gas-liquid mixture. A nozzle holder is attached to the tip of the nozzle holder, and a slit is formed therein, which is the nozzle for injecting the gas-liquid mixture supplied from the mixing chamber. A circular substrate in plan view disposed between the nozzle holder and the nozzle plate, a guide channel that penetrates the substrate in the thickness direction and guides the gas-liquid mixture supplied from the mixing chamber toward the slit, and a nozzle core having two fitting protrusions formed on the upper surface of the substrate that rise up and fit into the nozzle plate with a recessed and recessed design, The nozzle holder comprises an orifice plate housed on the base end side, having a pinhole formed therein for injecting the liquid supplied from the liquid supply pipe into the air inlet, The guide channel is asymmetrical when the diameter of the substrate perpendicular to the center line of each fitting projection is used as the line of symmetry between the opposing surfaces of each fitting projection, and is disposed at one location on the side of one of the fitting projections. A spray nozzle characterized in that the substrate of the nozzle core has an upright piece that rises from the upper surface of the substrate and is lower than the height position of the pre-spray plate, which is integrated with the inner upright surface of the fitting projection on the other side where the guide channel is not provided.

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