Spray nozzle

Abstract

To be able to stably prevent a cap, which is jointed with a screw to a nozzle main body of a spray nozzle to fix a tip member of the nozzle, from loosening with a simple structure.SOLUTION: An engagement part 13, in which mountain-shaped protrusions 13a having inclined surfaces at both sides in a circumferential direction are formed continuously in the circumferential direction, is provided at an inner periphery at a screw-in tip side of a cap 2. Engagement pieces 14, which is constituted of support parts 14a extending out obliquely with respect to a radial direction of a nozzle main body 1 and convex parts 14b leading to tip sides of the support parts 14a and engage with an engagement part 13 of the cap 2, are provided at an outer periphery of the nozzle main body 1. When tightening the cap 2, a protrusion 13a of the engagement part 13 rides over the convex parts 14b of the engagement pieces 14 while displacing the engagement pieces 14 to inside in the radial direction, so that the cap can be tightened smoothly. After the cap 2 is tightened completely, the cap 2 cannot be easily rotated, even when receiving force in a direction in which the cap 2 is loosened by vibration or the like.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a spray nozzle used for spraying liquids such as pesticides and water. [Background technology]

[0002] Spray nozzles used to spray liquids such as pesticides and water often comprise a cylindrical nozzle body with a liquid passageway formed through the axis and a male thread formed on the outer periphery of the tip, a nozzle tip member such as a spray plate or nozzle tip with an orifice through which liquid supplied to the liquid passageway of the nozzle body is sprayed as mist droplets, and a cap that is screwed onto the tip of the nozzle body and secures the nozzle tip member to the tip of the nozzle body with the orifice exposed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-51427 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned spray nozzle, the cap may loosen from the nozzle body due to vibration during use, and this loosening may cause the nozzle tip member, such as the nozzle plate or nozzle tip, to rotate. If the circumferential position of the nozzle tip member changes, the mist particles sprayed from the nozzle may be directed in an unintended direction, which may result in inefficient spraying of the liquid on the target object.

[0005] The solution to this problem would be to periodically retighten the cap, but with large sprayers (for example, boom sprayers with multiple spray nozzles attached at regular intervals along the length of a long boom), retightening the cap can be a cumbersome task.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a cap that is screwed to the nozzle body of a spray nozzle to secure a nozzle tip member thereto, and that has a simple structure and can be stably prevented from loosening. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides a spray nozzle comprising a cylindrical nozzle body having a liquid passage formed through its axial center and a male thread formed on the outer periphery of its tip, a nozzle tip member having an orifice for spraying liquid supplied to the liquid passage of the nozzle body, and a cap which is screwed to the tip of the nozzle body and fixes the nozzle tip member to the tip of the nozzle body with the orifice exposed, wherein the cap is provided with an engaging portion having a circumferentially continuous mountain-shaped protrusion having inclined surfaces on both circumferential sides on its inner periphery closer to the screw-in tip than the female thread which screw-connects with the male thread of the nozzle body, and the nozzle body is provided with an engaging piece which engages with the engaging portion of the cap and is capable of being displaced radially inward by elastic deformation on its outer periphery closer to the axial center than the male thread.

[0008] In the above configuration, when the nozzle tip member is fixed to the nozzle body, as the cap is screwed to the tip of the nozzle body, the engaging portion of the cap comes into contact with the engaging piece of the nozzle body, but if the force used to rotate the cap is increased to a certain extent, the protrusion of the engaging portion displaces the engaging piece radially inward by elastic deformation and overcomes the engaging piece, so that the cap can be tightened smoothly. Then, when the tightening is completed and the engaging portion and the engaging piece are engaged, even if a force is applied in a direction to loosen the cap due to vibration or the like, the cap can be stably prevented from loosening as long as the force is not large enough to cause the protrusion of the engaging portion to overcome the engaging piece.

[0009] In addition, the mechanism for preventing the cap from loosening in this manner is composed only of an engagement portion consisting of multiple mountain-shaped protrusions formed on the inner circumference of the screw-in tip side of the cap, and an engagement piece that is arranged on the outer circumference of the nozzle body so that it can be displaced radially inward, so that the structure is simple and does not increase the number of parts in the entire spray nozzle.

[0010] Here, the engaging piece may be composed of a support portion extending obliquely from the outer periphery of the nozzle body in the radial direction, and a protrusion continuing from the tip side of the support portion and fitting into a valley portion between adjacent protrusions in the circumferential direction of the cap. By using this engaging piece, the design of the resistance to loosening of the cap (ease of attachment and detachment) can be easily adjusted.

[0011] Furthermore, if a plurality of the engagement pieces are provided at equal intervals in the circumferential direction of the nozzle body, the force for rotating the cap is applied to the cap in a well-balanced manner, which is preferable. Effect of the Invention

[0012] As described above, the spray nozzle of the present invention is designed so that when the cap is screwed onto the nozzle body, the engaging portion consisting of multiple mountain-shaped protrusions formed on the inner circumference of the screwed-in tip side of the cap engages with the engaging piece provided on the outer circumference of the nozzle body so as to be displaceable radially inward, so that the cap can be stably prevented from loosening with a simple structure. Therefore, the rotation of the nozzle tip member due to vibration during use can be prevented, and liquid can be always accurately sprayed onto the target object without having to periodically retighten the cap. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is an external perspective view of a spray nozzle according to an embodiment; [Diagram 2] FIG. 2 is an exploded perspective view of the main part of the spray nozzle of FIG. 1; [Diagram 3] A longitudinal sectional front view of the spray nozzle of FIG. [Figure 4] Cross-sectional view taken along line IV-IV in Figure 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described with reference to Figures 1 to 4. As shown in Figures 1 to 3, this spray nozzle includes a cylindrical nozzle body 1 having a liquid passage 1a formed through its axis and a male thread 1b formed on the outer periphery of its tip, a cap 2 screwed to the tip of the nozzle body 1, a disk-shaped nozzle plate (nozzle tip member) 3 attached to the nozzle body 1 by the cap 2, an annular seal member 4 sealing between the nozzle plate 3 and the nozzle body 1, a core 5 arranged between the tip surface of the nozzle body 1 and the nozzle plate 3, an orifice plate 6 arranged in the liquid passage 1a near the rear end of the nozzle body 1, a cylindrical packing 7 in close contact with the rear end surface of the nozzle body 1, a filter 8 arranged inside the packing 7, a holder 9 holding the rear end of the nozzle body 1, a union nut 10 connecting the holder 9 to the nozzle body 1, and a lock nut 11 preventing the union nut 10 from loosening. Between the nozzle body 1 and the cap 2, a mechanism 12 for preventing the cap 2 from loosening relative to the nozzle body 1 (hereinafter referred to as the “loosening prevention mechanism”) is provided.

[0015] In the nozzle body 1, a pair of arc-shaped core receivers 1c are provided on the inner circumference of the large-diameter tip of the liquid passage 1a in a state where they slightly protrude from the tip face of the nozzle body 1, and a pair of pin holes 1d are provided in the stepped surface that forms the bottom of the large-diameter tip of the liquid passage 1a. Also, an air introduction hole 1e is provided in the longitudinal center, penetrating from the outer circumferential surface to the liquid passage 1a, and a flange 1f for engaging a union nut 10 is provided on the outer circumference of the rear end.

[0016] The cap 2 has an internal thread 2a formed on its inner periphery, which threadably engages with the external thread 1b of the nozzle body 1, and an internal flange 2b at its tip. Then, by threading the cap 2 to the nozzle body 1 with the nozzle plate 3 pressed against the tip face of the nozzle body 1 via the seal member 4, the outer peripheral edge of the nozzle plate 3 is clamped by the internal flange 2b, and the nozzle plate 3 is fixed to the nozzle body 1 together with the seal member 4 and the core 5.

[0017] The nozzle plate 3 is formed with a bulging portion 3a that has a U-shaped cross section and extends in the radial direction, and an orifice 3b is formed in the longitudinal center of the bulging portion 3a to spray the liquid supplied to the liquid passage 1a of the nozzle body 1. The nozzle plate 3 is fixed to the tip of the nozzle body 1 with the orifice 3b exposed by the cap 2.

[0018] The sealing member 4 is a general-purpose O-ring, which is compressed between the nozzle plate 3 and the tip surface of the nozzle body 1 when the cap 2 is tightened, thereby creating a liquid-tight seal between the nozzle plate 3 and the nozzle body 1.

[0019] The core 5 regulates the flow of the liquid that has passed through the liquid passage 1a after being mixed with air sucked in through the air inlet 1e of the nozzle body 1, and has two flow paths 5a that direct the liquid toward the spray plate 3. A pair of positioning pins 5b is provided on the back surface (surface on the nozzle body 1 side), and a pair of projections 5c is provided on the periphery of the front surface (surface on the spray plate 3 side). Each positioning pin 5b is inserted into a pin hole 1d of the nozzle body 1, and the core 5 is assembled in a state in which a part of the periphery of the back surface abuts against the core receiver 1c of the nozzle body 1. During this assembly, each projection 5c of the core 5 fits into a groove on the back surface (surface on the core 5 side) of the bulging portion 3a of the spray plate 3, thereby positioning the core 5 and the spray plate 3 in the circumferential direction.

[0020] The holder 9 has a liquid introduction passage 9a that communicates with the liquid passage 1a of the nozzle body 1 through the inner space of the packing 7, and is a member that is connected to a liquid supply source (not shown) such as an external liquid guide tube with its tip holding the rear end of the nozzle body 1 and the outer periphery of the packing 7.

[0021] The union nut 10 has an inner flange 10a at its tip, and by screwing it into the tip of the holder 9, the inner flange 10a tightens the flange 1f of the nozzle body 1 to connect the nozzle body 1 to the holder 9, and in this state the lock nut 11 prevents it from loosening.

[0022] Here, among the above-mentioned components, the spray plate 3, orifice plate 6 and filter 8 are made of stainless steel, the seal member 4 and packing 7 are made of rubber, and the other components are made of resin. The resin components can be replaced with other materials that are resistant to the liquid to be sprayed, but it is preferable that the nozzle body 1 is made of resin, as described later.

[0023] The anti-loosening mechanism 12, which prevents the cap 2 from loosening from the nozzle body 1, comprises an engagement portion 13 having a circumferentially continuous mountain-shaped protrusion 13a having inclined surfaces on both circumferential sides, provided on the inner circumference closer to the screw-in tip than the female thread 2a of the cap 2, as shown in Figures 3 and 4, and also comprises a pair of engagement pieces 14 which engage with the engagement portion 13 of the cap 2, provided at centrally symmetric positions on the outer circumference closer to the axial center than the male thread 1b of the nozzle body 1, as shown in Figures 2 to 4.

[0024] Each engagement piece 14 of the nozzle body 1 is composed of a support portion 14a extending obliquely from the outer periphery of the nozzle body 1 in the radial direction, and a convex portion 14b that is continuous with the tip side of the support portion 14a and fits into a valley between adjacent protrusions 13a in the circumferential direction of the cap 2, and is provided in a state in which it can be displaced radially inward of the nozzle body 1 by bending deformation of the support portion 14a. Here, each engagement piece 14 is formed of resin integrally with the nozzle body 1, and is designed so that an appropriate amount of displacement occurs by bending deformation of the support portion 14a.

[0025] By employing the above-mentioned locking mechanism 12, when the spray plate 3 is fixed to the nozzle body 1 together with the seal member 4 and the core 5, the cap 2 is screwed to the tip of the nozzle body 1, and the engagement portion 13 of the cap 2 comes into contact with the protrusions 14b of each engagement piece 14 of the nozzle body 1. However, if the force with which the cap 2 is rotated is increased to a certain degree at this time, the protrusions 13a of the engagement portion 13 bend the support portions 14a of the engagement pieces 14 and displace them radially inward, thereby overcoming the protrusions 14b of the engagement pieces 14, so that the cap 2 can be tightened smoothly. After the cap 2 is sufficiently tightened, the protrusions 14b of the engagement pieces 14 enter the valleys between the protrusions 13a adjacent to each other in the circumferential direction of the cap 2, completing the tightening.

[0026] In this manner, when the tightening of the cap 2 is completed and the engaging piece 14 of the nozzle body 1 is engaged with the engaging portion 13 of the cap 2, even if a force is applied in a direction to loosen the cap 2 due to vibration or the like, the cap 2 can be stably prevented from loosening as long as the force is not large enough to cause the protrusion 13a of the engaging portion 13 to overcome the convex portion 14b of the engaging piece 14.

[0027] On the other hand, when replacing the nozzle plate 3, etc., by simply rotating the cap 2 with a certain amount of force in the opposite direction to that used for tightening, the protrusion 13a of the engagement portion 13 will overcome the convex portion 14b of the engagement piece 14, so that the cap 2 can be smoothly loosened and removed from the nozzle body 1.

[0028] This spray nozzle has the above-mentioned configuration, in which liquid supplied from an external liquid source to liquid inlet passage 9a of holder 9 flows through filter 8 inside packing 7 into liquid passage 1a of nozzle body 1, passes through orifice plate 6 and mixes with air introduced from air inlet hole 1e, and is then rectified as it passes through flow path 5a of core 5, and is sprayed in the form of mist droplets from nozzle 3b of nozzle plate 3.

[0029] Here, the cap 2 that fixes the spray plate 3 to the nozzle body 1 is prevented from loosening from the nozzle body 1 by an anti-loosening mechanism 12, and is not easily rotated by vibration during use. Therefore, even without periodically retightening the cap 2, liquid can always be accurately sprayed onto the target object, eliminating the need for the conventional cumbersome task of retightening the cap.

[0030] In addition, the anti-loosening mechanism 12 is composed only of an engagement portion 13 consisting of multiple mountain-shaped protrusions 13a formed on the inner circumference of the cap 2 and an engagement piece 14 provided on the outer circumference of the nozzle body 1, so that the structure is simple and the number of parts in the entire spray nozzle is not increased.

[0031] Furthermore, since the engagement piece 14 of the nozzle body 1 has a support portion 14a extending obliquely from the outer periphery of the nozzle body 1 in the radial direction, the design of the resistance to loosening of the cap 2 (ease of attachment and removal) can be easily adjusted by changing the length and cross-sectional area of ​​the support portion 14a.

[0032] In addition, it is sufficient for at least one engagement piece to be provided on the outer periphery of the nozzle body, but if multiple engagement pieces are provided at equal intervals around the circumferential direction of the nozzle body as in this embodiment, the force rotating the cap is applied to the cap in a balanced manner, which is preferable.

[0033] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the above meaning, and is intended to include all modifications within the scope and meaning equivalent to the claims.

[0034] For example, the engaging piece is not limited to that in the embodiment, but may be any engaging piece that is displaceable radially inward of the nozzle body by elastic deformation.

[0035] Furthermore, the present invention can of course also be applied to a spray nozzle incorporating a nozzle end member (for example, a nozzle tip or the like) other than the spray plate as in the embodiment. [Explanation of symbols]

[0036] 1 Nozzle body 1a Liquid passage 1b Male thread 2 Cap 2a Female thread 3. Spray plate (nozzle tip part) 3b spout 12 Anti-loosening mechanism 13 Engagement part 13a protrusion 14 Engagement piece 14a Support part 14b Convex part

Claims

1. A spray nozzle comprising: a cylindrical nozzle body having a liquid passage formed through its axial center and a male screw formed on the outer periphery of its tip; a nozzle tip member having an orifice for spraying liquid supplied to the liquid passage of the nozzle body; and a cap that is screwed to the tip portion of the nozzle body and fixes the nozzle tip member to the tip of the nozzle body with the orifice exposed, The cap is provided with an engagement portion on an inner periphery on the screw-in tip side of the female thread that is screwed into the male thread of the nozzle body, the engagement portion having a circumferentially continuous mountain-shaped protrusion having inclined surfaces on both circumferential sides, A spray nozzle characterized in that the nozzle body has an engagement piece that engages with an engagement portion of the cap and is provided on the outer periphery of the nozzle body toward the axial center side of the male thread, the engagement piece being displaceable radially inward by elastic deformation.

2. 2. The spray nozzle according to claim 1, characterized in that the engagement piece comprises a support portion extending obliquely from an outer periphery of the nozzle body in the radial direction, and a convex portion continuing from a tip side of the support portion and fitting into a valley portion between adjacent protrusions in the circumferential direction of the cap.

3. 3. The spray nozzle according to claim 1, wherein a plurality of the engagement pieces are provided at equal intervals in the circumferential direction of the nozzle body.

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