WO2019078180A1

WO2019078180A1 - Emitter, and tube for drip irrigation

Info

Publication number: WO2019078180A1
Application number: PCT/JP2018/038402
Authority: WO
Inventors: 高橋　淳
Original assignee: 株式会社エンプラス
Priority date: 2017-10-18
Filing date: 2018-10-16
Publication date: 2019-04-25
Also published as: JP2019071855A

Abstract

This invention addresses the problem of providing an emitter with which it is possible to inhibit the occurrence of the siphon phenomenon, and to discharge an irrigation liquid in a satisfactory manner even if the pressure of the irrigation liquid in a tube is low. An emitter for solving the above problem has a first surface and a second surface, which are in an obverse-reverse relationship with each other. The emitter has: an intake for intaking an irrigation liquid, the intake being disposed on the first surface; a discharge unit for discharging the irrigation liquid, the discharge unit being disposed on the second surface; a channel linking the intake and the discharge unit, the channel channeling the irrigation liquid; and a backflow suppression unit for suppressing backflow of a fluid from the discharge unit side to the intake side, the backflow suppression unit being disposed partway along the channel. The backflow suppression unit includes a valve seat, a diaphragm part which moves farther away from the valve seat when a negative pressure is produced in the tube, and a valve body having one end fixed to the diaphragm part. When the diaphragm part moves away from the valve seat, the gap between the valve seat and the valve body becomes narrower.

Description

Emitter and drip irrigation tube

The present invention relates to an emitter and a drip irrigation tube having the emitter.

The drip irrigation method is known as one of the plant cultivation methods. The drip irrigation method is a method of disposing a drip irrigation tube on or in the soil where plants are planted, and dripping irrigation fluid such as water or liquid fertilizer from the drip irrigation tube onto the soil. In recent years, the drip irrigation method has drawn particular attention because it can minimize the consumption of irrigation liquid.

The drip irrigation tube generally includes a tube having a plurality of through holes through which the irrigation liquid is discharged, and a plurality of emitters (also referred to as "drippers") for discharging the irrigation liquid from the respective through holes. (See, for example, Patent Document 1).

The emitter described in Patent Document 1 comprises a first member having a water intake for taking in irrigation liquid, a second member having a discharge outlet for discharging irrigation liquid, a first member and a first member, And a membrane member disposed between the two members. The emitter is configured by superposing the first member, the membrane member and the second member in this order. The emitter is bonded to the inner wall of the tube. In the emitter described in Patent Document 1, when the pressure of the irrigation liquid deforms the membrane member and the water intake is opened, the irrigation liquid flows into the emitter, and the pressure reduction between the water intake and the discharge port It flows through the flow path and is discharged from the discharge port.

Unexamined-Japanese-Patent No. 2010-046094

In general, even after the liquid supply into the tube is stopped, the irrigation liquid in the tube is continuously discharged outside the tube for a certain period of time. When the drip irrigation tube is disposed at a position where the elevation difference is, the irrigation liquid flows from the high position to the low position after the liquid transfer is stopped. Therefore, the amount of discharge of the irrigation liquid from the emitter at the lower position is higher than that of the discharge of the irrigation liquid from the emitter at the higher position. Therefore, the inside of the tube at the high position is likely to be negatively pressurized, and a fluid such as air or water containing fine soil may flow from the outside of the tube into the flow path of the emitter disposed at the high position. When the backflow phenomenon of the fluid (hereinafter, also referred to as “siphon phenomenon”) caused by the negative pressure in the tube, the inside of the emitter may be contaminated or clogged.

On the other hand, in the emitter described in Patent Document 1, when the pressure of the irrigation liquid in the tube becomes less than a predetermined value after stopping the liquid transfer, the water intake is blocked by the membrane member. Therefore, the siphon phenomenon as described above does not easily occur. However, in the emitter described in Patent Document 1, even when the pressure in the tube is too low, the water intake port is blocked by the membrane member, so there is a problem that the irrigation liquid can not be properly discharged.

An object of the present invention is to provide an emitter and a drip irrigation tube capable of suppressing the occurrence of a siphon phenomenon and appropriately discharging the irrigation fluid even if the pressure of the irrigation fluid in the tube is low. .

In order to solve the above-mentioned subject, the emitter concerning the present invention has the 1st field and the 2nd field which are in the relation of the front and back, and is connecting the inside wall of the tube which distributes the liquid for irrigation, and the inside and outside of the tube An emitter for quantitatively discharging the irrigation liquid in the tube from the outlet to the outside of the tube when the nozzle is joined to a position corresponding to the outlet, and the emitter is disposed on the first surface, The water intake unit for taking in the irrigation liquid, the discharge unit disposed on the second surface and discharging the irrigation liquid, the water intake unit and the discharge unit are connected, and the irrigation liquid is circulated. And a backflow suppression unit disposed in the middle of the flow passage for suppressing backflow of fluid from the discharge unit side to the water intake unit side, the backflow suppression unit including a valve With a seat and flexibility, The valve seat is disposed on the first surface so as to be separated from the valve seat, and disposed with a gap between the diaphragm portion further separating from the valve seat when a negative pressure is generated in the tube, and the valve seat And a valve body having one end fixed to the diaphragm portion, and when the diaphragm portion moves in a direction away from the valve seat, a gap between the valve seat and the valve body is narrowed.

Moreover, in order to solve said subject, the tube for drip irrigation which concerns on this invention joins the tube which has a discharge outlet for discharging the liquid for irrigation, and the position corresponding to the said discharge outlet of the inner wall face of the said tube And an emitter according to the present invention.

According to the emitter and the drip irrigation tube according to the present invention, the occurrence of the siphon phenomenon can be suppressed, and the irrigation fluid can be appropriately discharged even if the pressure of the irrigation fluid in the tube is low.

FIGS. 1A and 1B are diagrams showing the configuration of a drip irrigation tube according to an embodiment. 2A and 2B are diagrams showing the configuration of an emitter according to an embodiment. 3A to 3C show the configuration of the emitter body. FIGS. 4A and 4B are diagrams showing the configuration of the first diaphragm, and FIGS. 4C and 4D are diagrams showing the configuration of the second diaphragm. 5A to 5C are schematic cross-sectional views for explaining the operation of the backflow suppressing portion of the emitter according to the embodiment. 6A to 6C are schematic cross-sectional views for explaining the operation of the flow rate adjuster of the emitter according to the embodiment. FIG. 7 is a view showing a configuration of a second diaphragm portion of an emitter according to a modification.

Hereinafter, the drip irrigation tube will be described in detail based on a specific embodiment. However, the drip irrigation tube is not limited to the embodiment.

[Configuration of drip irrigation tube]
FIGS. 1A and 1B are diagrams showing the configuration of a drip irrigation tube 100 according to an embodiment. FIG. 1A is a cross-sectional view in the direction along the axis of drip irrigation tube 100 according to the present embodiment, and FIG. 1B is a cross-sectional view in the direction perpendicular to the axis of drip irrigation tube 100. The drip irrigation tube 100 has a tube 110 having a discharge port 112 for discharging the irrigation liquid, and an emitter 120 joined at a position corresponding to the discharge port 112 of the inner wall surface of the tube 110.

The tube 110 is a tube for flowing irrigation liquid. The tube 110 is usually made of resin, and the material of the tube 110 is, for example, polyethylene such as linear low density polyethylene or high density polyethylene. The radial size of the tube 110 and the shape of the tube 110 may be such that the emitter 120 can be disposed inside the tube 110.

The tube wall of the tube 110 is formed with a plurality of discharge ports 112 for discharging the irrigation liquid at predetermined intervals (for example, 200 mm to 500 mm) in the axial direction of the tube 110. The diameter of the opening of the discharge port 112 may be, for example, 1.5 mm as long as the irrigation liquid can be discharged at a desired flow rate. Emitters 120 are respectively bonded to positions corresponding to the discharge ports 112 on the inner wall surface of the tube 110.

2A and 2B are diagrams showing the configuration of the emitter 120 according to the present embodiment. 2A is a plan view of the emitter 120, and FIG. 2B is a cross-sectional view taken along the line AA of FIG. 2A. The hatching of the first diaphragm portion 170 and the second diaphragm portion 180 is omitted.

The emitter 120 has a first surface 1201 and a second surface 1202 that are in front and back relationship with each other. In the present embodiment, the first surface 1201 is a surface disposed on the irrigation liquid side, and the second surface 1202 is disposed in contact with the tube 110.

The size and shape of the emitter 120 can be appropriately determined as long as the desired function can be exhibited. For example, the plan view shape of the emitter 120 is a substantially rectangular shape in which the four corners are R-chamfered, the length in the long side direction of the emitter 120 is 35 mm, and the length in the short side direction of the emitter 120 is 8 mm The height of the emitter 120 is 2.5 mm.

As shown in FIGS. 2A and 2B, the emitter 120 according to the present embodiment includes an emitter body 130, a first diaphragm portion 170 and a second diaphragm portion 180, and the first diaphragm portion 170 and the second diaphragm portion 180. The diaphragm portion 180 is joined to the emitter body 130.

3A to 3C are diagrams showing the configuration of the emitter main body 130 according to the present embodiment. 3A is a plan view of the emitter body 130, FIG. 3B is a bottom view of the emitter body 130, and FIG. 3C is a cross-sectional view taken along the line AA of FIG. 3A.

The emitter body 130 is molded of a resin material. Examples of the resin material include polyethylene such as linear low density polyethylene and high density polyethylene, polypropylene, silicone, and industrial materials having rubber elasticity. Examples of industrial materials having such rubber elasticity include elastomers and rubbers.

The emitter main body 130 has a substantially rectangular shape in a plan view. The shape of the second surface 1202 of the emitter body 130 is a convex curved surface along the inner wall surface of the tube 110. In the first surface 1201 and the second surface 1202 of the emitter body 130, recesses, grooves, protrusions and through holes are appropriately arranged.

More specifically, in the first surface 1201 of the emitter body 130, the first recess 131, the first cylindrical portion 132, the second recess 133, the second cylindrical portion 134, the first groove 136, the second groove A groove 137, a third groove 138 and a fourth groove 139 are formed. Further, from the first surface 1201 to the second surface 1202, the slits 140, the first holes 141, the second holes 142, the third holes 143, the fourth holes 144, and the fifth holes 145 are further formed. ing. On the other hand, on the second surface 1202 of the emitter main body 130, the fifth groove 150, the first depressurizing channel portion 151, the sixth groove 152, the second depressurizing channel portion 153, the third depressurizing channel portion A seventh groove 154 and a third recess 156 are further formed.

The first recess 131 opens at the central portion of the first surface 1201 of the emitter body 130. The first cylindrical portion 132 is disposed at the central portion of the bottom surface of the first recess 131. The second concave portion 133 is opened on the first surface 1201 of the emitter main body 130 to the outside of the first concave portion 131 in the longitudinal direction of the emitter main body 130. The second cylindrical portion 134 is disposed at the center of the bottom of the second recess 133. The plan view shape of each of the first recess 131 and the second recess 133 is circular. A second hole 142 is open on the top surface of the first cylindrical portion 132. A fifth hole 145 is open on the top surface of the second cylindrical portion 134. The first groove 136 is formed on the upper surface of the second cylindrical portion 134, and communicates the peripheral edge of the upper surface of the second cylindrical portion 134 with the fifth hole 145.

The depth of the first recess 131 (the distance from the first surface 1201 of the emitter body 130 to the bottom surface of the first recess 131) and the depth of the second recess 133 (the first surface 1201 of the emitter body 130 to the second The distances to the bottom surface of the recess 133 may be the same or different. In the present embodiment, the depths of the first recess 131 and the second recess 133 are the same.

The first cylindrical portion 132 protrudes from the bottom of the first recess 131, and the second cylindrical portion 134 protrudes from the bottom of the second recess 133. The height of the first cylindrical portion 132 is less than the depth of the first recess 131. The height of the second cylindrical portion 134 is less than the depth of the second recess 133. The heights of the first cylindrical portion 132 and the second cylindrical portion 134 may be the same as or different from each other. In the present embodiment, the first cylindrical portion 132 is higher than the height of the second cylindrical portion 134. The upper surface of the first cylindrical portion 132 is a flat surface, and the upper surface of the second cylindrical portion 134 is a slope (curved surface). The shape of the opening of the second hole 142 opened at the center of the upper surface of the first cylindrical portion 132 is circular, and the opening of the second hole 142 is open at the center of the upper surface of the second cylindrical portion 134. The shape of the opening of the hole 145 of 5 is also circular. That is, in the present embodiment, both the plan view shape of the first cylindrical portion 132 and the plan view shape of the second cylindrical portion 134 have an annular shape.

The first groove 136 is formed on the top surface of the second cylindrical portion 134. In the present embodiment, the number of first grooves 136 is one, and the shape in plan view is a linear shape. The first groove 136 has a constant depth from the top surface of the second cylindrical portion 134, and has a bottom surface parallel to the top surface.

The first hole 141 opens at the bottom of the first recess 131. The second hole 142 is open at the central portion of the first cylindrical portion 132. The third hole 143 and the fourth hole 144 are open at the bottom of the second recess 133. The fifth hole 145 opens at the central portion of the second cylindrical portion 134. The plan view shapes of the first hole 141, the second hole 142, the third hole 143, the fourth hole 144, and the fifth hole 145 are all circular.

The emitter body 130 also has a filter portion 147 including a second groove 137, a third groove 138 and a fourth groove 139, and a slit 140 disposed in the filter portion 147. The filter portion 147 and the slit 140 are disposed outside the first recess 131 on the other side in the longitudinal direction of the emitter body 130.

The filter portion 147 is a fine asperity formed on the first surface 1201 of the emitter body 130. The filter portion 147 has a U-shaped second groove 137 along the edge of the other end in the longitudinal direction of the emitter body 130, and the second groove 137 and the outside extending from the second groove 137. And a plurality of fourth grooves 139 extending inward from the second groove 137. The fourth grooves 139 mainly extend independently along the lateral direction of the emitter body 130, and parts of the fourth grooves 139 communicate with each other.

The slit 140 is an elongated through hole that opens along the longitudinal direction of the emitter body 130 at one end in the lateral direction of the emitter body 130. The slits 140 are opened at the bottom of the plurality of fourth grooves 139 in the filter portion 147 on the first surface 1201 of the emitter body 130.

In addition, a fifth groove 150 is formed in the second surface 1202 of the emitter body 130. The fifth groove 150 extends along the longitudinal direction at one end in the lateral direction of the emitter body 130. The first depressurization channel portion 151 extends along the longitudinal direction at one end in the lateral direction. One end of the first depressurizing channel 151 communicates with one end of the fifth groove 150. The sixth groove 152 extends along the short direction at the other longitudinal end of the emitter body 130. The sixth groove 152 is provided at the other end of the first depressurizing channel portion 151, one end of the second depressurizing channel portion 153, and the third depressurizing flow in the longitudinal inner portion. It communicates with one end of the passage 154. The second depressurization channel portion 153 extends along the longitudinal direction at the central portion in the lateral direction. The third depressurization channel portion 154 extends along the longitudinal direction at the other end in the lateral direction. The seventh groove 155 extends in the central portion of the second surface 1202 of the emitter body 130 along the longitudinal direction. The third recess 156 is formed on the second surface 1202 of the emitter body 130 outside the fifth groove 150, the seventh groove 155, and the third depressurizing channel portion 154 in the longitudinal direction. .

Each of the first pressure reduction flow channel portion 151, the second pressure reduction flow channel portion 153, and the third pressure reduction flow channel portion 154 is a groove whose planar shape is a zigzag shape. The zig-zag shape is, for example, a shape formed by alternately arranging convex portions in a substantially triangular prism shape from both side surfaces of the pressure reducing channel portion along the longitudinal direction. For example, when the emitter main body 130 is viewed from the bottom, the convex portion is disposed such that the tip end of the convex portion does not exceed the central axis between the side surfaces.

At the bottom of the fifth groove 150, a slit 140 is opened. A first hole 141 is open at the other end of the second pressure reduction flow channel portion 153. At one end of the seventh groove 155, a second hole 142 is opened, and at the other end of the seventh groove 155, a third hole 143 is opened. A fourth hole 144 is open at the other end of the third depressurizing channel 154. A fifth hole 145 opens at the inside of the bottom of the third recess 156.

The third recess 156 is disposed across the outer end of the second surface 1202 of the emitter body 130. In the third concave portion 156, a second convex portion 157, a third convex portion 158, a fourth convex portion 159, and a fifth convex portion 160 are disposed.

The second convex portion 157 extends along the short side direction, and is disposed at a position overlapping the fifth hole 145 in the longitudinal direction. The third convex portion 158 is disposed at a position on the extension of the second convex portion 157 in the short direction away from any of the side walls of the second convex portion 157 and the third concave portion 156. The fourth convex portion 159 extends from the side wall of the third concave portion 156 along the short direction, and a gap between the third convex portion 158 and the side wall of the third concave portion 156 in the longitudinal direction. It is arranged in the position which overlaps with. The fifth convex portion 160 extends along the extension of the fourth convex portion 159 in the lateral direction, and side walls of the second convex portion 157 and the third convex portion 158 in the longitudinal direction. And the gap between the

4A and 4B are diagrams showing the configuration of the first diaphragm portion 170, and FIGS. 4C and 4D are diagrams showing the configuration of the second diaphragm portion 180. As shown in FIG. 4A and 4B are diagrams showing the configuration of the first diaphragm portion 170, and FIGS. 4C and 4D are diagrams showing the configuration of the second diaphragm portion 180. As shown in FIG. FIG. 4A is a cross-sectional view of the first diaphragm portion 170 passing through the central axis, and FIG. 4B is a bottom view of the first diaphragm portion 170. 4C is a cross-sectional view of the second diaphragm 180 passing through the central axis, and FIG. 4D is a bottom view of the second diaphragm 180.

The first diaphragm portion 170 and the second diaphragm portion 180 are made of resin and have flexibility. Examples of the resin material include polyethylene such as linear low density polyethylene and high density polyethylene, polypropylene, silicone, and industrial materials having rubber elasticity. Examples of industrial materials having such rubber elasticity include elastomers and rubbers. The resin material of the first diaphragm portion 170 may be the same as or different from the resin material of the emitter body 130. In addition, the resin material of the first diaphragm portion 170 may be the same as or different from the resin material of the second diaphragm portion 180.

The first diaphragm portion 170 extends in the normal direction of the first film portion 171 from the first film portion 171 having a circular shape in plan view and the peripheral portion of the first film portion 171. And a first peripheral wall portion 173. The first peripheral wall portion 173 is not shown in FIG. 2B and FIGS. 5A to 5C and FIGS. 6A to 6C, which will be described later. The first peripheral wall portion 173 is disposed inside the outer edge portion of the first film portion 171. The diameter of the first film portion 171 is larger than the diameter of the first recess 131, and the diameter of the first peripheral wall portion 173 is the same as the diameter of the first recess 131. The portion of the first film portion 171 outside the first peripheral wall portion 173 and the first peripheral wall portion 173 are disposed on the emitter body 130 so as to sandwich the corner of the opening of the first recess 131 Be done. Thereby, the first diaphragm portion 170 is reliably and easily positioned at a desired position. At this time, the first film portion 171 and the upper surface of the first cylindrical portion 132 are disposed with a gap.

On the other hand, the second diaphragm 180 has a second film 181 having a circular shape in a plan view, and a second peripheral wall 183 extending in the normal direction of the second film 181. doing. The second peripheral wall portion 183 is not shown in FIG. 2B and FIGS. 5A to 5C and FIGS. 6A to 6C described later. In the present embodiment, one end of the valve body 182 is fixed to the center of the second film portion 181 of the second diaphragm portion 180, and the second diaphragm portion 180 and the valve body 182 are integrally formed. There is.

The second peripheral wall portion 183 of the second diaphragm portion 180 is disposed inside the outer edge portion of the second film portion 181. The diameter of the second film portion 181 is larger than the diameter of the second recess 133, and the outer diameter of the second peripheral wall 183 is the same as the diameter of the second recess 133. The portion of the second film portion 181 outside the second peripheral wall portion 183 and the second peripheral wall portion 183 are disposed on the emitter main body 130 so as to sandwich the corner of the opening of the second recess portion 133. Be done. Thereby, the second diaphragm portion 180 is reliably and easily positioned at a desired position. At this time, the second film portion 181 and the upper surface of the second cylindrical portion 134 are disposed with a gap.

Here, the valve body 182, one end of which is fixed to the second diaphragm portion 180, is a valve when the second membrane portion (the second diaphragm portion 180) is bent in a direction away from the second surface 1202. It consists of a valve body main part 182b which approaches the seat (wall surface 145w of the fifth hole) and suppresses backflow of fluid, and a valve body shaft part 182a connecting the second membrane part 181 and the valve body main body 182b. . The valve body 182 is second from the end of the valve body main body 182 b on the side of the diaphragm portion 180 of the valve seat (the wall surface 145 w of the fifth hole), that is, the opening on the second cylindrical portion 134 side of the fifth hole 145. It is positioned so as to be located on the surface 1202 side.

The outer shape of the valve main body 182b in the present embodiment is substantially a truncated cone in which the diameter in the horizontal cross section of the valve main body 182b decreases toward the second diaphragm 180 (the second membrane 181). It is a state. Further, with the maximum diameter of the valve body 182b, a sufficient gap is formed between the valve body 182b and the valve seat (the wall surface of the fifth hole 145) when the second membrane portion 181 is not bent. When the second membrane portion is bent in the direction away from the second surface 1202, the gap between the valve body 182b and the valve seat (the wall surface of the fifth hole 145) may be sufficiently narrow. Just do it. The diameter (maximum diameter) of the tip portion of the valve body 182 b can be, for example, 90% or more of the maximum diameter of the fifth hole 145, and may be larger than the maximum diameter of the fifth hole 145. On the other hand, the height of the valve body 182b is not particularly limited, and in the present embodiment, the height of the fifth hole 145 (from the opening on the second cylindrical portion 134 side of the fifth hole 145 to the third hole And the distance to the opening on the side of the concave portion 156). Further, in the present embodiment, the central portion of the valve body main body 182b is a hollow having a substantially truncated cone shape, and the thickness of the outer peripheral wall of the valve body main body 182b is substantially uniform.

The shape of the valve body shaft portion 182a may be any shape that does not prevent the movement of the valve body main body 182b accompanying the operation of the second diaphragm portion 180. In the present embodiment, the cross section of the valve body main body 182b in the horizontal direction is It is cylindrical with a diameter substantially the same as the minimum diameter. Further, in the present embodiment, the height of the valve stem portion 182a is made equal to the distance between the second film portion 181 and the second cylindrical portion 134.

The emitter 120 having the above-described structure is manufactured by manufacturing the emitter body 130, the first diaphragm portion 170, and the second diaphragm portion 180 (including the valve body 182), respectively, and joining them. can do. For example, by fitting the peripheral wall portion 173 of the first diaphragm portion 170 into the first recess 131 of the emitter main body 130 and fitting the peripheral wall portion 183 of the second diaphragm portion 180 into the second recess 133 of the emitter main body 130 Thus, an emitter 120 in which the emitter body 130, the first diaphragm portion 170, and the second diaphragm portion 180 are integrated is obtained. In the present embodiment, the valve body 182 b of the valve body 182 is inserted into the fifth hole 145 at the same time as the peripheral wall portion 183 of the second diaphragm portion 180 is fitted. As described above, since the hollow is provided in the central portion of the valve body 182b, the valve body 182b can be inserted from the opening of the fifth hole 145 on the second cylindrical portion 134 side. However, the method of manufacturing the emitter 120 is not limited to this method. For example, the valve body 182 and the second diaphragm portion 180 are manufactured separately, and the valve body 182 is opened from the third recess 156 side opening of the fifth hole 145. The valve body shaft portion 182a may be inserted, and the valve body 182 and the second diaphragm portion 180 may be integrated.

The first diaphragm portion 170 and the second diaphragm portion 180 fitted in the emitter body 130 are joined by welding or fusion of resin materials constituting them, or adhesion by an adhesive.

As described above, the emitter 120 has the second surface 1202 of the emitter body 130 joined to the inner wall surface of the tube 110. Thus, a drip irrigation tube 100 as shown in FIG. 1A, B is produced. The ejection port 112 may be formed in the tube 110 in advance before bonding of the emitter 120 or may be formed after bonding of the emitter 120.

[Operation of tube for drip irrigation]
In a state where the emitter 120 is joined to the tube 110, the filter portion 147, the slit 140 and the fifth groove 150 become a water intake portion 200 for taking in the irrigation liquid flowing in the tube 110. On the other hand, the third concave portion 156 of the emitter 120 is joined so as to communicate with the discharge port 112 of the tube 110, and becomes the discharge portion 500 for discharging the irrigation solution. In the emitter 120, the water intake portion 200 and the discharge portion 500 are connected by a channel formed of a groove, a through hole, or the like provided in the emitter 120. Furthermore, in the middle of the flow path, a backflow suppression unit 300 for suppressing the backflow of fluid from the discharge unit 500 side to the water intake unit 200 side is disposed. In addition, the arrangement position of the backflow suppressing portion 300 is not particularly limited, and may be disposed at an end of the flow path, that is, in a region in communication with the discharge portion 500 or the water intake portion 200. It is also good. In the present embodiment, the backflow suppressing portion 300 is disposed in a region in communication with the discharge portion 500.

Here, in the emitter 120 according to the present embodiment, a flow rate adjustment unit for adjusting the amount of irrigation liquid discharged from the discharge unit 500 of the emitter 120 according to the pressure of the irrigation liquid inside the tube 110 ( A first flow control unit 700 and a second flow control unit 800) are also provided.

An outline of the flow of irrigation liquid in such a drip irrigation tube 100 will be described. The irrigation liquid supplied into the tube 110 is supplied to the fifth groove 150 through the grooves (second groove 137, third groove 138 and fourth groove 139) of the filter portion 147 and the slit 140. Be done. The irrigation liquid can be, for example, water, liquid fertilizer, pesticide, or a mixture of two or more thereof. Since the suspended matter in the irrigation liquid can not enter the groove of the filter portion 147, the irrigation liquid from which the suspended matter is removed is supplied to the fifth groove 150 through the slit 140.

The irrigation liquid supplied to the fifth groove 150 is supplied to the branch flow channel while being decompressed through the first pressure reduction channel 151. A part of the irrigation liquid supplied to the branch flow channel is supplied to a first flow rate adjustment unit 700 described later while being further depressurized through the second pressure reduction flow channel (sixth groove 152). . Then, it is supplied to the below-mentioned 2nd flow rate adjustment part 800 via a connecting channel (seventh slot 155). Further, the remainder of the irrigation liquid supplied to the branch flow channel (sixth groove 152) is supplied to the second flow rate adjustment unit 800 while being further depressurized through the third pressure reduction channel unit 154. . The irrigation liquid supplied to the second flow rate adjustment unit 800 is supplied to the discharge unit 500 at a flow rate adjusted according to the fluid pressure of the irrigation liquid in the tube 110 and discharged from the discharge port 112. In the present embodiment, the second flow rate adjusting unit 800 also serves as the above-described backflow suppressing unit 300.

Hereinafter, the flow path including the water intake portion 200, the first pressure reduction flow path portion 151, the second pressure reduction flow path portion 153, the first flow rate adjustment portion 700, the second flow rate adjustment portion 800, and the discharge portion 500 It is called "1 flow path". Further, a flow path including the water intake portion 200, the first pressure reduction flow path portion 151, the third pressure reduction flow path portion 154, the second flow rate adjustment portion 800, and the discharge portion 500 is also referred to as a "second flow path".

(Backflow suppression unit)
The backflow suppression unit 300 will be described in detail. The backflow suppressing portion 300 of the emitter 120 according to the present embodiment includes the fifth hole 145, the second diaphragm portion 180, and the valve body 182. The backflow suppression unit 300 is in communication with the discharge unit 500 (third concave portion 156). On the other hand, it is in communication with the below-mentioned 1st flow rate adjustment part via the 2nd crevice 133, the 3rd hole 143, and the 7th slot 155. Further, it is also in communication with the flow path (the third pressure reduction flow path 154) via the second recess 133 and the fourth hole 144.

In the backflow suppressing portion 300 of the present embodiment, the valve body 182 b of the valve body 182 is disposed in the fifth hole 145, and the wall surface 145 w of the fifth hole 145 (hereinafter simply referred to as “valve seat 145 w” Also functions as a valve seat. In the present specification, the wall surface 145 w of the fifth hole may be a surface located around the fifth hole 145, and the opening on the third concave portion 156 side may be the second cylindrical portion 134 side. It may be a cylindrical surface having a uniform diameter over the opening, or may be a tapered surface whose diameter decreases from the opening on the third concave portion 156 side to the opening on the second cylindrical portion 134 side. . In the present embodiment, the valve seat 145 w is a tapered surface whose diameter decreases from the opening on the third concave portion 156 side toward the opening on the second cylindrical portion 134 side. Further, the second diaphragm portion 180 is disposed apart from the valve seat 145w in a non-loaded state, and bends away from the valve seat 145w when a negative pressure is generated in the tube 110.

In addition, as described above, the valve body 182b has a gap between the valve body 182b and the valve seat 145w when the second diaphragm 180 (the second film 181) is not bent. It is arranged as. Hereinafter, the operation of the backflow suppression unit 300 will be described. 5A to 5C show a partial schematic cross-sectional view of the backflow suppressor 300 of the emitter 120. FIG.

When the irrigation liquid flows in the tube 110, the second film portion 181 does not bend or bends to the second surface side (in FIG. 5A, the second film portion 181 is not bent) Show). At this time, a sufficient gap is generated between the valve body 182b and the valve seat 145w, and the irrigation liquid flows from the water intake 200 side toward the discharge part 500 through the gap.

On the other hand, when negative pressure is generated in the tube 110 in the vicinity of the emitter 120, for example, when the supply of irrigation liquid is stopped, the second film portion 181 is bent in the direction away from the valve seat 145w as shown in FIG. 5B. Well. As a result, the gap between the valve body 182 b and the valve seat 145 w is narrowed. Then, as shown in FIG. 5C, when the second film portion 181 further moves in the direction away from the valve seat 145w, the valve body 182b and the valve seat 145w abut, or the gap becomes very narrow. As a result, the backflow of the fluid from the discharge unit 500 side to the water intake unit 200 side is suppressed.

Further, when the supply of the irrigation liquid into the tube 110 is started or the negative pressure in the tube 110 in the vicinity of the emitter 120 is eliminated, as shown in FIG. 5A, the second film portion 181 is flat Or bend to the second side 1202. As a result, the contact state (or very narrow gap) of the valve body 182b and the valve seat 145w is eliminated, and the irrigation liquid can flow from the water intake portion 200 toward the discharge portion 500. It becomes.

(Flow adjustment part)
Next, the first flow control unit 700 and the second flow control unit 800 will be described. The first flow rate adjustment unit 700 of the present embodiment is configured of a first recess 131, a first cylindrical portion 132, a first hole 141, a second hole 142, and a first diaphragm portion 170. The first flow rate adjusting unit 700 is in communication with the second pressure reducing flow passage 153 via the first hole 141, and via the second hole 142, the seventh groove 155 and the third hole 143. The second flow control unit 800 communicates with the second flow control unit 800. In the first flow rate adjustment unit 700, the upper surface of the first cylindrical portion 132 functions as a first flow rate adjustment valve seat 132s on which the first film portion 171 of the first diaphragm portion 170 is seated. The first diaphragm portion 170 is disposed apart from the first flow control valve seat 132s in a state not receiving a load, and when the pressure of the irrigation liquid in the tube 110 is received, the first diaphragm portion 170 Approach the valve seat 132s.

In addition, the second flow rate adjusting unit 800 includes the second recess 133, the second cylindrical portion 134, the third hole 143, the fourth hole 144, the fifth hole 145, the first groove 136, and the first It comprises the two diaphragm parts 180. The second flow rate adjusting unit 800 is in communication with the third pressure reducing flow passage 154 via the fourth hole 144, and via the third hole 143, the seventh groove 155 and the second hole 142. It communicates with the first flow rate adjustment unit 700. On the other hand, it is in communication with the later-described discharge unit 500 through the fifth hole 145. In the second flow rate adjustment unit 800, the upper surface of the second cylindrical portion 134 functions as a second flow rate adjustment valve seat 134s on which the second film portion 181 of the second diaphragm portion 180 is seated. The second diaphragm portion 180 is disposed apart from the second flow control valve seat 134s in a non-loaded state, and receives the pressure of the irrigation liquid in the tube 110. Approach 134s.

6A to 6C are partial enlarged cross-sectional views for describing control of the flow rate (discharge) of the irrigation liquid by the first flow rate adjustment unit 700 and the second flow rate adjustment unit 800. FIG. 6A is a cross-sectional view schematically showing the state of the first flow rate adjusting unit 700 and the second flow rate adjusting unit 800 under the non-pressure condition and the extremely low pressure condition of the emitter 120, and FIG. 6C is a cross-sectional view schematically showing the state of the first flow rate adjusting unit 700 and the second flow rate adjusting unit 800 under the low pressure condition of FIG. FIG. 7 is a cross-sectional view schematically showing the state of 700 and a second flow rate adjustment unit 800.

(No pressure condition and extremely low pressure condition)
As shown in FIG. 6A, when the hydraulic pressure of the irrigation liquid is 0 MPa, the irrigation liquid does not flow in the emitter 120, so no pressure difference (differential pressure) occurs between the inside and the outside. Thus, neither the first diaphragm portion 170 nor the second diaphragm portion 180 is deformed.

On the other hand, when the hydraulic pressure of the irrigation liquid is an extremely low pressure (for example, about 0.005 MPa) (extreme low pressure condition), the irrigation liquid flows in the tube 110 and the emitter 120. At this time, in the first flow rate adjustment unit 700, the hydraulic pressure (external hydraulic pressure) of the irrigation liquid in the tube 110 and outside the emitter 120 and the hydraulic pressure (internal of the irrigation liquid in the first recess 131) A slight difference occurs with the fluid pressure). Specifically, the internal fluid pressure in the first flow rate adjustment unit 700 becomes lower than the external fluid pressure due to the pressure loss in the first pressure reduction flow passage portion 151 and the second pressure reduction flow passage portion 153. Similarly, the internal fluid pressure in the second flow rate adjustment unit 800 is greater than the external fluid pressure due to the pressure loss in the first pressure reduction flow passage portion 151, the third pressure reduction flow passage portion 154, and the first flow rate adjustment portion 700. Also lower.

However, under the extremely low pressure condition, since the differential pressure is sufficiently small, neither the first diaphragm portion 170 nor the second diaphragm portion 180 is deformed (see FIG. 6A). Therefore, the irrigation liquid introduced from the water intake portion 200 is discharged from the discharge port 112 of the tube 110 to the outside through both the first flow path and the second flow path.

(Under low pressure conditions)
When the hydraulic pressure of the irrigation liquid is low (for example, about 0.02 MPa) (under low pressure conditions), the first diaphragm portion 170 is bent as shown in FIG. 6B due to the above-mentioned differential pressure. When the first diaphragm portion 170 bends, the gap between the first diaphragm portion 170 and the first flow control valve seat 132 s narrows, and the flow rate of the irrigation liquid flowing through the gap decreases. Similarly, the second diaphragm portion 180 of the second flow rate adjusting portion 800 is also bent due to the differential pressure, and as shown in FIG. 6B, between the second diaphragm portion 180 and the second flow rate adjusting valve seat 134s. The gap narrows. As a result, the flow rate of the irrigation liquid discharged from the discharge port 112 becomes smaller than the extremely low pressure condition.

(Under medium and high pressure conditions)
When the liquid pressure of the irrigation liquid is medium to high pressure (for example, 0.1 MPa) (under medium to high pressure conditions), the first diaphragm portion 170 is largely bent as shown in FIG. 6C due to the above-mentioned differential pressure. When the first diaphragm portion 170 is largely bent, the first diaphragm portion 170 and the first flow control valve seat 132 s approach each other, and the flow rate of the irrigation liquid in the first flow path is almost eliminated.

On the other hand, as shown in FIG. 6C, the second diaphragm portion 180 is also largely bent by the differential pressure between the external hydraulic pressure and the internal hydraulic pressure, and the two diaphragm portions 180 and the second valve seat 134s for flow rate adjustment Will abut. However, the fifth hole 145 communicates with the second circular recess 133 via the first groove 136. Therefore, a predetermined amount of irrigation liquid flows into the fifth hole 145 via the first groove 136, and the irrigation liquid is discharged from the discharge port 112. At this time, the flow rate of the irrigation liquid discharged from the discharge port 112 is smaller than that under the low pressure condition.

[effect]
In the emitter 120 according to the present embodiment, the backflow suppression unit 300 is provided in the middle of the flow path between the water intake unit 200 and the discharge unit 300. In the backflow suppressing portion 300, when a negative pressure is generated in the tube 110, the second diaphragm portion 180 (valve seat (145W)) moves in a direction away from the second surface. Further, at this time, the valve body 182, one end of which is fixed to the second diaphragm portion 180, moves so that the gap between the valve seat 145w and the valve body 182 becomes narrow. Therefore, the backflow (siphon phenomenon) of the fluid from the discharge part 300 side to the water intake part 200 side is suppressed. Therefore, according to the drip irrigation tube 100 having the emitter 120 according to the present embodiment, the occurrence of clogging of the flow path due to the siphon phenomenon is suppressed even in a place having a height difference.

On the other hand, when the irrigation liquid flows in the tube 110, the second diaphragm portion 180 becomes flat, or the second diaphragm portion 180 approaches the valve seat 145w. Therefore, in these states, a constant gap is generated between the valve seat 145w and the valve body 182, and the irrigation liquid can be properly discharged even if the pressure of the irrigation liquid in the tube 110 is low. .

[Modification]
In the above embodiment, an example in which the valve body main body 182b of the valve body 182 is substantially frusto-conical has been described, but the shape of the valve body main body 182b is the direction in which the second diaphragm 180 separates from the valve seat 145w. The gap between the valve seat 145 w and the valve body 182 b may be narrow when moving to the side, for example, as shown in FIG. 7 (cross-sectional view of the second diaphragm 180 passing through the central axis) It may be present, or may be polygonal, spherical or the like.

Moreover, in the above-mentioned embodiment, although the 2nd diaphragm part 180 of the 2nd flow rate adjustment part 800 served as the diaphragm part of the backflow prevention part 300, the backflow prevention part 300 and the 2nd flow rate adjustment part 800 separately It may be arranged. Moreover, although the above-mentioned embodiment demonstrated to the example the emitter in which two flow volume adjustment parts (1st flow volume adjustment part 700 and 2nd flow volume adjustment part 800) are arrange | positioned, these may not necessarily be required.

When the side walls of the second groove 137, the third groove 138, and the fourth groove 139 in the filter portion 147 are a so-called wedge wire structure, pressure loss in the filter portion 147 can be suppressed. It is more effective from the viewpoint of suppressing clogging and is preferable.

This application claims the priority based on Japanese Patent Application No. 2017-201964 filed Oct. 18, 2017. The contents described in the application specification and drawings are all incorporated herein by reference.

According to the emitter of the present invention, it is possible to suppress the occurrence of clogging due to the backflow of the fluid outside the tube to the flow path even at a place where there is a difference in elevation. Therefore, further development of drip irrigation is expected.

DESCRIPTION OF SYMBOLS 100 drip irrigation tube 110 tube 112 discharge port 120 emitter 130 emitter main body 131 1st recessed part 132 1st cylindrical part 132s 1st valve seat for flow adjustment 133 2nd recessed part 134 2nd cylindrical part 134s 2 valve seat 136 1st groove 137 2nd groove 138 3rd groove 139 4th groove 140 slit 141 1st hole 142 2nd hole 143 3rd hole 144 4th hole 145 5th hole 145 w fifth hole wall (valve seat)
147 filter portion 150 fifth groove 151 first pressure reducing channel portion 152 sixth groove 153 second pressure reducing channel portion 154 third pressure reducing channel portion 155 seventh groove 156 third concave portion 157 second The convex portion 158 The third convex portion 159 The fourth convex portion 160 The fifth convex portion 170 The first diaphragm portion 171 The first film portion 172 The valve body 173 The first peripheral wall portion 180 The second diaphragm portion 181 The first diaphragm portion 2 membrane portion 182 valve body 182a valve body shaft portion 182b valve body main body 183 second peripheral wall portion 200 intake portion 300 backflow suppressing portion 500 discharge portion 700 first flow rate adjusting portion 800 second flow rate adjusting portion

Claims

Having a first surface and a second surface that are in front and back relationship with each other
When it is joined to the inner wall surface of the tube for circulating the irrigating liquid and a position corresponding to the discharge port communicating the inside and the outside of the tube, the irrigating liquid in the tube is quantified outside the tube from the discharge port. An emitter for discharging
A water intake unit disposed on the first surface for taking in the irrigation liquid;
A discharge unit disposed on the second surface for discharging the irrigation liquid;
A flow path for connecting the water intake portion and the discharge portion and circulating the irrigation liquid;
A reverse flow suppression unit disposed in the middle of the flow path, for suppressing a reverse flow of fluid from the discharge unit side to the water intake unit side;
Have
The backflow suppressing portion has a valve seat and flexibility, and is disposed on the first surface so as to be separated from the valve seat, and further away from the valve seat when a negative pressure is generated in the tube. And a valve body disposed with a gap between the diaphragm portion and the valve seat, and having one end fixed to the diaphragm portion,
When the diaphragm moves away from the valve seat, the gap between the valve seat and the valve body narrows.
Emitter.
At least a portion of the valve body is on the second surface side from an end on the diaphragm portion side of the valve seat,
The emitter according to claim 1.
At least a part of the valve body is a truncated cone whose diameter decreases as it approaches the diaphragm portion;
An emitter according to claim 1 or 2.
The emitter according to any one of claims 1 to 3, wherein the diaphragm portion and the valve body are integrated.
A tube having a discharge port for discharging the irrigation liquid;
The emitter according to any one of claims 1 to 4, which is joined at a position corresponding to the discharge port on the inner wall surface of the tube.
Having a drip irrigation tube.