JP7543109B2 - Liquid Spray Nozzle - Google Patents

Description

The present invention relates to a liquid spray nozzle.

As a solution to the declining and aging agricultural workforce in Japan, transplanting machines have been developed, as well as techniques for raising rice and vegetables in seedling boxes. However, raising seedlings in seedling boxes requires a lot of preparatory work, such as filling the containers with soil, sowing the rice seeds, applying fertilizers and pesticides required during the seedling raising period, and watering the seedling boxes after sowing.

Some farmers outsource the entire process of preparing seedlings to seedling centers, but for farmers who do not outsource the work, the complicated task of preparing seedling trays and seedling beds is a heavy burden.

As an example of preparation work, pesticide spraying, liquid fertilizer spraying, irrigation, etc. are carried out to uniformly manage the growth of each seedling, but it is necessary to spray as uniform amounts as possible. In a typical seedling tray (cell-molded seedlings) for vegetable seedlings, 128 to 200 seedlings are grown in an area of 30 cm x 60 cm in small cells, each with its own soil and independent conditions. Therefore, even a slight deviation in the water injection position can result in large differences in the amounts of pesticides, liquid fertilizer, and irrigation sprayed on each cell.

For example, the Ministry of Agriculture, Forestry and Fisheries instructs that pesticides should be used appropriately according to the applicable crops, application time, and application method (dilution ratio, amount of solution sprayed, etc.) listed on the pesticide label. If the amount of pesticide solution is not uniform, there is a risk that the pesticide will not be effective enough, which could lead to the occurrence of pests and diseases, which could affect the growth of seedlings.

In addition, with regard to the application of liquid fertilizer and irrigation, because each of the aforementioned cells is an independent environment, farmers are instructed to adhere to the recommended application amounts so that there are no differences in the amount of water in each cell. If the amount of liquid fertilizer or irrigation is uneven between cells, this could lead to poor seedling growth or the occurrence of spiny seedlings.

For this reason, when spraying pesticides, liquid fertilizer, irrigation, etc., it is necessary to do so appropriately so that the amount of liquid per unit area is within the allowable range. In contrast, when spraying pesticides, etc. using a typical commercially available watering can, the area (especially the width direction) that is treated on the tray surface after the pesticide is dispersed from the watering hole changes depending on the height position of the watering can, which can lead to large variations in the amount of liquid sprayed per unit area, and there is also a problem of bias in the amount of liquid discharged between the center and periphery of the nozzle.

In response to these problems, Patent Document 1 discloses a pesticide applicator in which a nozzle equipped with a nozzle section having a number of holes arranged in a row and a width approximately equal to the overall width of the seedling tray or seedling box is connected to a nozzle connection tube of a container. By simply moving this pesticide applicator in one direction, it is possible to evenly spray pesticides and the like on the vegetable seedlings contained in the seedling box, which is said to greatly improve the efficiency of pesticide spraying work.

Patent No. 5825471 specification

The nozzle in Patent Document 1 has holes lined up in a row in the width direction, which means that the amount sprayed per unit area is small. Therefore, when it is necessary to spray a relatively large amount of pesticide, etc., the sprayer must be held above the seedling tray and moved slowly at a constant speed to spray, or the sprayer must be moved back and forth multiple times. This leads to variation in the amount of pesticide sprayed and also increases the time required for spraying.

On the other hand, if the diameter of the holes is simply increased, the amount of crop sprayed per unit area will increase. However, there is a risk that the forceful water flow coming out of the large holes will damage the seedlings and gouge the soil.

On the other hand, one idea is to aim to increase the amount sprayed per unit area by modifying the nozzle of Patent Document 1 to form two or more rows of holes along the width direction. However, according to the inventor's research, it was found that, for example, if the nozzle of Patent Document 1 is modified to form two or more rows of holes aligned in the width direction, there is a risk of uneven spraying between the center side and both width sides of the nozzle.

In view of the above problems, the present invention aims to provide a liquid spray nozzle that can quickly perform uniform spraying while ensuring the amount sprayed per unit area.

In order to solve the above problems, one representative liquid spray nozzle of the present invention is as follows:
A liquid spray nozzle including a water guide portion connected to a water supply source, a housing portion connected to the water guide portion, and a shower plate closing an end face of the housing portion,
the shower plate has a dimension in a first direction that is at least twice as large as a dimension in a second direction perpendicular to the first direction, and has a plurality of rows of through holes aligned along the first direction;
An end flow path is formed inside the water guide portion, and a diffusion flow path is formed which communicates with the end flow path and reaches an inner surface of the shower plate,
a main branch portion having an upstream side and a downstream side extending along the first direction is formed in a center of the diffusion channel,
This is achieved by forming a gap between the end of the main branch portion in the first direction and the inner wall of the diffusion channel.

According to the present invention, it is possible to provide a liquid spray nozzle that can quickly perform uniform spraying while ensuring the amount of spraying per unit area.
Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments.

FIG. 1 is a perspective view of a nozzle according to a first embodiment. FIG. 2 is a plan view of the nozzle according to the present embodiment. FIG. 3 is a side view of the nozzle according to this embodiment. FIG. 4 is a front view of the nozzle according to this embodiment. FIG. 5 is a cross-sectional view of the nozzle of FIG. 3 taken along line BB and viewed in the direction of the arrows. FIG. 6 is a cross-sectional view of the nozzle of FIG. 2 taken along line AA and viewed in the direction of the arrows. FIG. 7 is a cross-sectional view of the nozzle of FIG. 2 taken along line CC and viewed in the direction of the arrows. FIG. 8 is a schematic diagram illustrating the nozzle assembly process. FIG. 9 is a diagram for explaining a mode of use of the nozzle. FIG. 10 is a schematic diagram showing the flow of liquid inside the nozzle with arrows. FIG. 11 is a cross-sectional view similar to FIG. 5 of a nozzle according to a second embodiment. FIG. 12 is a diagram showing a state in which liquid is sprayed from a nozzle of a comparative example attached to a water injection pipe of a watering can. FIG. 13 is a diagram showing a state in which liquid is sprayed from the nozzle of Example 1 attached to the water injection pipe of a watering can. FIG. 14 is a diagram showing a state in which liquid is sprayed from the nozzle of Example 2 attached to the water injection pipe of a watering can. FIG. 15 is a diagram showing a state in which liquid is sprayed from the nozzle of Example 3 attached to the water injection pipe of a watering can.

[First embodiment]
A first embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a perspective view of a liquid spray nozzle (hereinafter simply referred to as a nozzle) 10 according to the first embodiment. Fig. 2 is a plan view of the nozzle 10. Fig. 3 is a side view of the nozzle 10. Fig. 4 is a front view of the nozzle 10.

As shown in FIG. 3, the nozzle 10 is formed by joining the lower body half 10A, the upper body half 10B, and the shower part 10C. The manufacturing process of the nozzle 10 will be described later.

First, the external appearance of the nozzle 10 as a finished product will be described.
1 and 2, the nozzle 10 is a generally T-shaped structure in which a generally hollow cylindrical water-guiding section 11 is connected to the center of an elongated housing section 12, and is formed by joining a lower body half section 10A and an upper body half section 10B. Here, the longitudinal direction of the housing section 12 is defined as the x-direction (first direction or width direction), the axial direction of the water-guiding section 11 is defined as the y-direction, and the direction perpendicular to the x-direction and y-direction is defined as the z-direction (second direction).

A male thread 11a is formed on the outer periphery of the end of the water guide section 11. In addition, a circular recess 11b is formed on the top and bottom surfaces of the water guide section 11, and a segmented circular recess 12a is formed on the top and bottom surfaces of the center of the housing section 12. These recesses 11b and 12a were formed during the manufacturing process of the nozzle 10, and are disposed in the lower body half 10A and the upper body half 10B, respectively.

As shown in FIG. 3, the z-direction dimension of the housing 12 is larger than the outer diameter of the water guide 11 on the side closer to the shower section 10C.

The end face of the housing part 12 opposite to the water guide part 11 (y direction) is open, and this end face is closed by a rectangular flat shower plate 13. As shown in FIG. 4, the dimension of the shower plate 13 in the x direction is at least twice as large as the dimension in the z direction, and preferably at least three times as large. The shower plate 13 also has three rows of through holes 13a aligned in the x direction along the z direction. The through holes 13a are aligned in a staggered pattern, but may also be aligned in a matrix, and the number of rows may be two or four or more. The pitch of the through holes 13a in the same row is preferably equal, but may also be unequal. The shower plate 13 is integrated with an outer frame 13b that surrounds its periphery to form the shower part 10C.

Next, the internal structure of the nozzle 10 will be described.
Fig. 5 is a cross-sectional view of the nozzle in Fig. 3 taken along line B-B and viewed in the direction of the arrows. Fig. 6 is a cross-sectional view of the nozzle 10 in Fig. 2 taken along line A-A and viewed in the direction of the arrows. Fig. 7 is a cross-sectional view of the nozzle 10 in Fig. 2 taken along line C-C and viewed in the direction of the arrows. The axis of the water-guiding section 11 is designated as L.

As shown in Figures 5 and 6, a water conduit 14 is formed inside the nozzle 10. The water conduit 14 has an end flow path 14a formed on the inside end of the water conduit section 11, a diffusion flow path 14b that reaches the inner surface of the shower plate 13, and an intermediate flow path 14c that connects the end flow path 14a and the diffusion flow path 14b. The end flow path 14a and the intermediate flow path 14c are formed inside the water conduit section 11, and the diffusion flow path 14b is formed inside the housing section 12.

The end flow passage 14a has a substantially constant inner diameter inside the male thread 11a. As shown in FIG. 6, the inner dimension of the intermediate flow passage 14c gradually increases as it approaches the diffusion flow passage 14b in the z direction, and as shown in FIG. 5, the inner dimension of the intermediate flow passage 14c gradually increases as it approaches the diffusion flow passage 14b in the x direction. The width of the expansion of the intermediate flow passage 14c is greater in the x direction than in the z direction. In the cross section of FIG. 5, the shape of the inner walls on both sides of the intermediate flow passage 14c can be approximated by an inwardly convex arc.

In contrast, the diffusion flow channel 14b has a substantially constant internal dimension in the z direction, as shown in FIG. 6. Also, as shown in FIG. 5, the diffusion flow channel 14b has an internal dimension (width) in the x direction that increases at a substantially constant rate on the side closer to the intermediate flow channel 14c (the inclination angle with respect to the axis L is constant), and furthermore, the internal dimension in the x direction is substantially constant near the shower plate 13. The intermediate flow channel 14c and the diffusion flow channel 14b are smoothly joined.

As shown in Figures 5 and 6, a pair of cylindrical parts 15 are arranged near the center of the intermediate flow path 14c, embedded in the upper and lower walls of the water conducting part 11 with their ends butted together. The axis of the cylindrical parts 15 intersects with the axis L of the water conducting part 11. The inside of the cylindrical parts 15 corresponds to the recess 11b (see Figure 1).

A circular protrusion 15a is formed at the tip of one cylindrical portion 15, and a circular recess 15b is formed at the tip of the other cylindrical portion 15. The circular protrusion 15a and the circular recess 15b fit together to position the lower body half 10A and the upper body half 10B.

As shown in FIG. 5, in the diffusion flow path 14b near the boundary with the intermediate flow path 14c, a pair of segmented circular raised portions 16 are arranged to protrude inward from the upper and lower walls of the housing portion 12. The interior of the raised portions 16 corresponds to the depression 12a (see FIG. 1). The raised portions 16, which have the same shape, have a roughly flat upstream side surface 16a and a downstream side surface 16b, which will be described in detail later. The upstream side surface 16a and the downstream side surface 16b are connected by a smooth curved surface. Here, the raised portions 16 form the main flow division portion, and the cylindrical portion 15 forms the sub-flow division portion.

The upstream side 16a of the raised portion 16 is preferably a substantially flat surface extending in the x and z directions, but may be slightly inclined as it moves away from the upper or lower wall, for example, for molding reasons. In contrast, the entire downstream side 16b is formed by a curved surface.

The shape of the downstream side surface 16b will be described in more detail. In FIG. 5, the downstream side surface 16b has an arc-shaped outer edge centered on a point on the axis L of the water conducting section 11, and the outer dimension in the x direction decreases as it approaches the shower plate 13. In FIG. 7, the downstream side surface 16b has an arc-shaped outer edge centered on a point on a z-direction line (not shown) that intersects with the axis L of the water conducting section 11, and the outer dimension in the x direction decreases as it approaches the axis L.

In FIG. 5, the ratio (W2/W1) of the x-direction width W2 of the raised portion 16 to the maximum x-direction width W1 of the diffusion channel 14b is preferably in the range of 4/5 to 1/10, more preferably in the range of 1/2 to 1/4, and even more preferably 1/3.

As shown in FIG. 7, the pair of raised portions 16 abut against each other at the abutment portion 16c near the center. The ratio (W3/W1) of the x-direction abutment width W3 of the abutment portion 16c to the maximum x-direction width W1 of the diffusion channel 14b is preferably in the range of 1/8 to 1/10. By forming the abutment portion 16c, for example, when the water pressure applied to the nozzle 10 is relatively high, the balance of the water flow toward the shower plate 13 can be ensured. However, for example, when the water pressure applied to the nozzle 10 is low, the abutment portion 16c may not be provided and the x-direction abutment width W3 may be set to zero.

(Nozzle manufacturing process)
8 is a schematic diagram illustrating the assembly process of the nozzle 10. The manufacturing process of the nozzle 10 will be described with reference to FIG.

First, molten resin is injected into a metal mold (not shown) and then hardened after clamping to form the lower body half 10A, the upper body half 10B, and the shower portion 10C. At this time, in order to prevent molding defects, it is desirable to make the resin thickness as constant as possible, but it may be made thicker locally near the male thread 11a. To make the thickness constant, a pair of cylindrical portions 15 are formed corresponding to the recess 11b, and a pair of raised portions 16 are formed corresponding to the recess 12a. The lower body half 10A and the upper body half 10B have a common shape except for the different shapes of the male thread 11a and the cylindrical portion 15.

Then, as shown in Figure 8, the lower body half 10A and the upper body half 10B are joined by fitting the bodies together, using an adhesive to reinforce the connection, or by welding. At this time, as described above in relation to Figure 5, the circular convex portion 15a and the circular concave portion 15b of the cylindrical portion 15 fit together to position the lower body half 10A and the upper body half 10B. In addition, the male thread 11a of the water guide portion 11 is formed in a spiral shape that connects the lower body half 10A and the upper body half 10B.

Furthermore, the outer frame 13b of the shower part 10C is joined to the open end of the housing part 12 formed by the joined lower half part 10A and upper half part 10B of the main body by a fitting structure between the main bodies, by using an adhesive to reinforce the connection, or by welding. With the above steps, the nozzle 10 is completed.

Figure 9 is a diagram illustrating the use of the nozzle 10, showing only the vicinity of the water guide section 11 of the nozzle 10. In the use mode of Figure 9 (a), the water injection tube TB of a watering can (not shown in its entirety) is inserted inside the water guide section 11. Since a typical water injection tube TB has a tapered shape, the nozzle 10 can be easily attached to a watering can, which is a water supply source, simply by inserting the water injection tube TB into the water guide section 11. When a sprayer stores liquid such as pesticide in a watering can and then holds the watering can and points the water injection tube TB downward, the liquid that has entered the nozzle 10 from the water injection tube TB due to the action of gravity is discharged uniformly through the through holes 13a of the shower plate 13, allowing the liquid to be sprayed.

On the other hand, in the usage mode shown in FIG. 9(b), a nut NT connected to one end of the pressurized tube PT is screwed onto the male thread 11a of the water guide section 11. The male thread 11a and the female thread of the nut NT are liquid-tight. The other end of the pressurized tube PT is connected to a pump, which is a water supply source. When liquid is pumped from the water supply source through the pressurized tube PT to the nozzle 10, the liquid that has entered the nozzle 10 is ejected evenly through the through holes 13a of the shower plate 13, allowing the liquid to be sprayed.

(Liquid flow in the nozzle)
10 is a schematic diagram showing the flow of liquid inside the nozzle 10 with arrows. As shown in the figure, liquid that has entered the end flow path 14a inside the water guide section 11 flows toward the intermediate flow path 14c, and when it hits the central cylindrical section 15, it also creates a branch flow on both sides in the x direction. Since the inner dimension of the intermediate flow path 14c in the x direction gradually expands near the cylindrical section 15, the branched liquid is not retained and the liquid flows smoothly. The liquid that has passed through the cylindrical section 15 flows toward the raised section 16 as shown by the arrows.

The liquid that reaches the raised portion 16 while being separated to both sides in the x direction is divided by the upstream side 16a, and is further divided into liquid that flows toward both sides in the x direction (solid arrows) and liquid that passes through the gap CL1 between the pair of raised portions 16 shown in FIG. 7 and wraps around to the back side of the raised portion 16 (dotted arrows). The liquid that wraps around to the back side of the raised portion 16 reaches the central region of the shower plate 13 in the diffusion flow path 14b and is discharged from the through hole 13a in the central region. The gap CL1 becomes larger as it approaches both ends of the raised portion 16, which allows the flow rate of liquid flowing toward the center of the shower plate 13 to be adjusted.

In contrast, the liquid flowing toward both sides in the x direction passes through the relatively narrow gap CL2 between the inner wall of the intermediate flow path 14c and the raised portion 16 and enters the diffusion flow path 14b. When passing through this narrow gap CL2, the flow of the liquid is accelerated, so that the liquid reaches the end region of the shower plate 13 and is ejected from the through-hole 13a in the end region.

After passing through the narrow gap CL2, part of the liquid flows along the surface of the downstream side 16b and wraps around to the rear side of the raised portion 16. This allows the liquid to reach the intermediate region between the central region and the end region of the shower plate 13, and is ejected from the through-hole 13a in the intermediate region.

The above action allows a uniform amount of liquid to be discharged from each of the multiple rows of through holes 13a arranged along the x direction across the entire surface of the shower plate 13. This allows a large amount of liquid to be sprayed uniformly in one spray, shortening the time required to hold the watering can and reducing the burden on the sprayer.

In addition, with the nozzle 10 of this embodiment, liquid is ejected from each through hole 13a in a direction perpendicular to the surface of the shower plate 13, so even if the height position of the watering can to which the nozzle 10 is attached is changed, the amount of liquid sprayed per unit area does not change. Therefore, appropriate liquid spraying can be performed regardless of the height difference of the spraying worker or whether the worker is walking up or down while working.

As shown in FIG. 9(a), when spraying from the nozzle 10 is performed by gravity alone, the pair of raised portions 16 shown in FIG. 5 may be spaced apart. On the other hand, as shown in FIG. 9(b), when liquid is pumped from the water supply source, the liquid enters the water guide portion 11 with force, so by abutting the pair of raised portions 16 against each other, the liquid moving toward the central region of the shower plate 13 can be suppressed.

Second Embodiment
Fig. 11 is a cross-sectional view of a nozzle 10' according to a second embodiment similar to Fig. 5. The nozzle 10' has a water guide section 11, a housing section 12, a shower plate 13, and a pair of flow dividing plates 17. The shower plate 13 of the nozzle 10' is the same as that of the first embodiment, and a duplicated description will be omitted.

In this embodiment, too, the inner circumference of the hollow cylindrical water conducting section 11 forms the end flow path 14a. The inner wall of the housing section 12 to which the water conducting section 11 is connected forms the diffusion flow path 14b that communicates with the end flow path 14a. As shown in FIG. 11, the outer edge of the diffusion flow path 14b describes a parabola that is symmetrical with respect to the axis L of the water conducting section 11. Such a shape of the housing section 12 is called a dome shape.

The nozzle 10' of this embodiment forms a flow dividing plate 17 instead of a cylindrical portion and a raised portion. The pair of flow dividing plates 17 constituting the main flow dividing portion are elongated thin plates that extend along the same plane in the x direction of the water guide portion 11 and are connected to the housing portion 12. The end flow path 14a side of the flow dividing plate 17 is the upstream side, and the shower plate 13 side is the downstream side. A gap is formed between the opposing edges of the pair of flow dividing plates 17. In order to enhance the flow dividing effect, a semi-cylindrical surface (or a curved surface) that connects the upstream side and the downstream side is formed at the x direction end of the flow dividing plate 17. Here, the ratio (W2/W1) of the x direction width W2 of the flow dividing plate 17 to the x direction maximum width W1 of the diffusion flow path 14b is preferably in the range of 4/5 to 1/10, more preferably in the range of 1/2 to 1/4, and more preferably 1/3.

In this embodiment as well, part of the liquid that has entered from the water guide section 11 is repelled by the pair of diverter plates 17 and then diverted in an arc inside the dome-shaped housing section 12, and the remainder passes through the gap between the opposing edges of the pair of diverter plates 17 toward the central region of the shower plate 13. Some of the repelled liquid flows toward both sides in the x direction and reaches the end regions of the shower plate 13 through a relatively large gap between the x-direction ends of the diverter plate 17 and the diffusion flow channels 14b, and the remainder of the repelled liquid flows around to the back side of the diverter plate 17 and toward the intermediate region between the central region and the end region of the shower plate 13.
Due to the above action, liquid can be uniformly discharged from each of the through holes 13a provided over the entire surface of the shower plate 13. It is not necessary to provide a gap between the opposing edges of the pair of flow dividing plates 17. In that case, a single flow dividing plate can be provided. Also, as in the first embodiment, in addition to the flow dividing plate 17 as the main flow dividing section, a cylindrical section as a sub flow dividing section may be provided in the water guide section 11.

(Experimental Results)
The inventor actually produced examples and comparative examples of nozzles, and conducted a spray test using them. The results are described below. First, as a comparative example, a nozzle without a cylindrical portion and a raised portion was produced. Also, as Example 1, a nozzle formed with only a raised portion was produced. Furthermore, as Example 2, a nozzle with a cylindrical portion and a raised portion was produced similarly to the first embodiment. In addition, as Example 3, a nozzle with a flow dividing plate was produced similarly to the second embodiment. However, the housing and the flow dividing plate of Example 3 are formed of a transparent resin material.

These nozzles were attached to the water injection pipe of a watering can that contained liquid (water), and the liquid was sprayed from the nozzle by gravity. The spraying state is shown in Figures 12 to 15.

As shown in FIG. 12, in the nozzle of the comparative example, some of the liquid discharged from the through-holes immediately merged, and uniform dispersion was not achieved. In contrast, as shown in FIG. 13, the nozzle of Example 1 enabled more uniform dispersion of liquid than the nozzle of the comparative example, and it was confirmed that the flow-diverting effect of the raised portion was effective. Furthermore, as shown in FIG. 14, in the nozzle of Example 2, the liquid was discharged from the through-holes in a direction perpendicular to the surface of the shower plate, enabling even more uniform dispersion of the liquid, and it was confirmed that the flow-diverting effect of the cylindrical portion in addition to the raised portion was effective. In addition, as shown in FIG. 15, the nozzle of Example 3 also enabled uniform dispersion of the liquid, and it was confirmed that the flow-diverting effect of the flow-diverting plate was effective.

Therefore, by using the nozzle of the present invention, anyone can easily, quickly and uniformly spray pesticides, liquid fertilizer and irrigate seedling trays and seedling beds. This significantly improves the efficiency of agricultural work, eliminates waste of pesticides and liquid fertilizer and allows for processing as specified.

The present invention is not limited to the above embodiment, and various modifications can be made. For example, the nozzle can be formed by press molding a metal material, not limited to resin molding.

10, 10' Nozzle 11 Water guide section 12 Housing section 13 Shower plate 14 Water guide channel 15 Cylindrical section (sub-division section)
16. Raised section (main branch section)
17 Diverter plate (main diverter section)

Claims (7)

A liquid spray nozzle including a water guide portion connected to a water supply source, a housing portion connected to the water guide portion, and a shower plate closing an end face of the housing portion,
the shower plate has a dimension in a first direction that is at least twice as large as a dimension in a second direction perpendicular to the first direction, and has a plurality of rows of through holes aligned along the first direction;
An end flow path is formed inside the water guide portion, and a diffusion flow path is formed which communicates with the end flow path and reaches an inner surface of the shower plate,
a main branch portion having an upstream side and a downstream side extending along the first direction is formed in a center of the diffusion channel,
A liquid spray nozzle, characterized in that a gap is formed between an end of the main branch portion in the first direction and an inner wall of the diffusion flow path. The liquid spray nozzle according to claim 1, characterized in that, when the maximum dimension of the diffusion flow path in the first direction is W1 and the dimension of the main branch section in the first direction is W2, 4/5 ≧ W2/W1 ≧ 1/10 is satisfied. The liquid spray nozzle according to claim 1 or 2, characterized in that the main branch section is arranged to protrude inside the housing section, the upstream side is flat, and the downstream side is configured as a curved surface whose dimension in the first direction becomes smaller as it approaches the shower plate. The liquid spray nozzle according to claim 3, characterized in that a pair of the main branch sections are arranged to protrude inward from both walls of the housing section in the second direction, and the dimensions of the curved surfaces of each downstream side surface in the first direction become smaller as they approach each other. The liquid spray nozzle according to claim 1 or 2, characterized in that the main branch section is a thin plate that protrudes from the inside of the housing section and extends in the first direction. A liquid spray nozzle according to any one of claims 1 to 5, characterized in that a sub-division section protruding inwardly from the housing section is disposed between the end flow path and the main diversion section of the diffusion flow path. The liquid spray nozzle according to claim 6, characterized in that the sub-division section has a cylindrical shape and is disposed in an intermediate flow passage whose dimension in the first direction increases as it approaches the main diversion section.

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