JP2019129785A - Emitter and tube for drip irrigation - Google Patents

Abstract

To provide an emitter capable of suppressing clogging due to a foreign matter even when a foreign matter enters a channel.SOLUTION: An emitter comprises: a water intake part for taking a liquid for irrigation; a discharge part arranged to face a discharge hole of a tube, and discharges the liquid for irrigation; and a channel for connecting the water intake part and the discharge part, and circulating the liquid for irrigation. The channel includes a columnar pressure reduction channel, the pressure reduction channel has a plurality of salients arranged on one side and the other side sandwiching a center shaft thereof, and the salients provided on the one side and salients provided on the other side are alternately arranged in a flow direction of the liquid for irrigation.SELECTED DRAWING: Figure 5

Description

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

  For some time, drip irrigation has been known as one of the methods for growing plants. The drip irrigation method is a method in which a drip irrigation tube is arranged on soil in which plants are planted, and irrigation liquid such as water or liquid fertilizer is dropped from the drip irrigation tube to the soil. In recent years, drip irrigation has attracted particular attention because it can minimize the consumption of irrigation liquid.

  A drip irrigation tube usually has a tube formed with a plurality of through holes through which irrigation liquid is discharged, and a plurality of emitters (also referred to as “drippers”) for discharging the irrigation liquid from each through hole. . As types of emitters, there are known an emitter that is used while being joined to the inner wall surface of the tube (see, for example, Patent Document 1), and an emitter that is used by piercing the tube from the outside.

  FIG. 1 is a perspective view showing a configuration of an emitter 1 described in Patent Document 1 that is used by being joined to the inner surface of a tube. As shown in FIG. 1, the emitter 1 includes a water intake port 3 for taking in irrigation liquid, a discharge port 4 for discharging the irrigation liquid, and a flow path 2 connecting them. The channel 2 has a plurality of convex portions 5 that alternately project from both sides of the side surface of the channel 2 in the flow direction of the irrigation liquid.

  The emitter 1 described in Patent Document 1 is used in a state where the surface on which the flow path 2 is formed is joined to the inner surface of the tube. The drip irrigation tube using the emitter 1 described in Patent Document 1 can supply the irrigation liquid at a desired flow rate and is clogged with foreign particles such as sand particles and precipitates accumulated in the flow path 2. It is said that this can be suppressed. As a reason why clogging can be suppressed, eddy currents are generated between adjacent convex portions 5.

JP-A-5-276841

  However, in the emitter described in Patent Document 1, the vortex flow is generated in a plane (two-dimensional) substantially parallel to a plane including the flow direction and the width direction of the flow channel, and therefore the flow channel 2 is two-dimensionally generated. It could only be stirred. As a result, when foreign matter flows into the flow path 2, the foreign matter is likely to be deposited between adjacent convex portions 5, and clogging due to the accumulation of foreign matter may not be sufficiently suppressed.

  The present invention has been made in view of such circumstances, and provides an emitter and a drip irrigation tube that are less likely to be clogged by foreign matter even if foreign matter flows into the flow path. Objective.

  The emitter according to the present invention is configured to discharge the irrigation liquid in the tube when the emitter is joined to a position corresponding to a discharge port communicating between the inside and the outside of the tube on the inner wall surface of the tube through which the irrigation liquid flows. An emitter for quantitatively discharging the irrigation liquid from an outlet, the intake section for taking in the irrigation liquid, and a discharge for discharging the irrigation liquid, which is disposed facing the discharge port And a flow path that connects the water intake section and the discharge section and circulates the irrigation liquid. The flow path includes a columnar reduced pressure flow path, and the reduced pressure flow path has a central axis thereof. A plurality of convex portions disposed on one side and the other side of the irrigation liquid, and the convex portion disposed on the one side and the convex portion disposed on the other side are the liquid for irrigation Are alternately arranged in the flow direction.

  The drip irrigation tube according to the present invention includes a tube having a discharge port for discharging the irrigation liquid and an emitter according to the present invention joined to a position corresponding to the discharge port on the inner wall surface of the tube. And having.

  The emitter and drip irrigation tube according to the present invention can provide an emitter and drip irrigation tube that are less likely to be clogged by foreign matter even if foreign matter flows into the flow path.

FIG. 1 is a diagram showing a configuration of a conventional emitter. FIG. 2 is a cross-sectional view of the drip irrigation tube according to the present embodiment. 3A and 3B are diagrams showing the configuration of the emitter according to the present embodiment. 4A and 4B are diagrams showing the configuration of the emitter according to the present embodiment. 5A to 5C are diagrams showing the configuration of the emitter according to the present embodiment. FIG. 6 is a perspective view showing a configuration of a comparative emitter. 7A and 7B are conceptual diagrams showing the flow of irrigation liquid in the comparative emitter. FIG. 8 is a perspective view showing the configuration of the emitter according to the present embodiment. 9A and 9B are conceptual diagrams showing the flow of irrigation liquid in the emitter according to the present embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Composition of drip irrigation tube and emitter)
FIG. 2 is a cross-sectional view in the direction along the axis of the drip irrigation tube 100 according to the present embodiment.

  As shown in FIG. 2, the drip irrigation tube 100 includes a tube 110 and an emitter 120.

  The tube 110 is a tube for flowing an irrigation liquid. The material of the tube 110 is not particularly limited. In the present embodiment, the material of the tube 110 is polyethylene. A plurality of discharge ports 112 for discharging irrigation liquid at predetermined intervals (for example, 200 to 500 mm) in the axial direction of the tube 110 are formed on the tube wall of the tube 110. The diameter of the opening of the discharge port 112 is not particularly limited as long as the irrigation liquid can be discharged. In the present embodiment, the diameter of the opening of the discharge port 112 is 1.5 mm. Emitters 120 are respectively joined to positions corresponding to the discharge ports 112 on the inner wall surface of the tube 110. The cross-sectional shape and cross-sectional area perpendicular to the axial direction of the tube 110 are not particularly limited as long as the emitter 120 can be disposed inside the tube 110.

  The emitter 120 is joined to the inner wall surface of the tube 110 so as to cover the discharge port 112. The shape of the emitter 120 is not particularly limited as long as it can adhere to the inner wall surface of the tube 110 and cover the discharge port 112. In the present embodiment, the shape of the back surface 142 (the back surface 142 of the second emitter body 140 described later) joined to the inner wall surface of the tube 110 in the cross section of the emitter 120 perpendicular to the axial direction of the tube 110 is A substantially arcuate shape that is convex toward the inner wall surface of the tube 110 along the wall surface. The shape of the emitter 120 in plan view is a substantially rectangular shape with four corners rounded. The size of the emitter 120 is not particularly limited. In the present embodiment, the length of the emitter 120 in the long side direction is 25 mm, the length in the short side direction is 8 mm, and the height is 2.5 mm.

  The emitter 120 may be formed of a material having flexibility, or may be formed of a material having no flexibility. Examples of the material of the emitter 120 include resin and rubber. Examples of the resin include polyethylene and silicone. The flexibility of the emitter 120 can be adjusted by the elastic modulus of the resin material. The molded product of the emitter 120 can be manufactured by injection molding, for example. The configuration of the emitter 120 will be described in detail separately.

  The drip irrigation tube 100 is manufactured by joining the back surface 142 of the emitter 120 to the inner wall surface of the tube 110. The method for joining the tube 110 and the emitter 120 is not particularly limited. Examples of a method for joining the tube 110 and the emitter 120 include welding of a resin material that constitutes the tube 110 or the emitter 120, adhesion using an adhesive, and the like. Normally, the discharge port 112 is formed after the tube 110 and the emitter 120 are joined, but may be formed before joining.

  3A is a plan view of the emitter 120 (a plan view of the first emitter body 130), and FIG. 3B is a bottom view of the emitter 120 (a first emitter body 130 with a second emitter body 140 described later) removed. FIG. 4A is a plan view of the emitter 120 (a plan view of the second emitter body 140) in a state where a first emitter body 130 described later is removed, and FIG. 4B is a bottom view of the emitter 120 (second emitter body 140). FIG. 5A is a cross-sectional view taken along line 5A-5A shown in FIG. 3A, FIG. 5B is a cross-sectional view taken along line 5B-5B shown in FIG. 3A, and FIG. 5C is a cross-sectional view taken along line 5C shown in FIGS. 3B and 4A. It is sectional drawing of a -5C line. In the first emitter body 130 or the second emitter body 140, the surface on the central axis side of the tube 110 is referred to as a front surface 131 or 141, and the surface on the inner wall surface side of the tube 110 is referred to as a back surface 132 or 142.

  As shown in FIG. 5B, the emitter 120 has a first emitter body 130 and a second emitter body 140.

  The first emitter body 130 includes a water intake 150, a first connection groove 160 that becomes the connection flow path 220, a first pressure reduction groove 170 that becomes the pressure reduction flow path 230, and a discharge recess 180 that becomes the discharge part 240 (FIG. 3A). And B). The water intake unit 150 is disposed on the surface 131 side of the first emitter 130. The first connection groove 160, the first decompression groove 170, and the discharge recess 180 are disposed on the back surface 132 side of the first emitter body 130. The first decompression groove 170 has a plurality of protrusions 231 at the bottom, and is arranged so as to connect the first connection groove 160 and the discharge recess 180.

  The second emitter body 140 includes a second connection groove 190 that becomes the connection flow path 220, a second pressure reduction groove 200 that becomes the pressure reduction flow path 230, and a discharge hole 210 that becomes the discharge portion 240 (see FIG. 4A). The second connection groove 190 and the second decompression groove 200 are disposed on the surface 141 side of the second emitter body 140 at positions corresponding to the first connection groove 160 and the first decompression groove 170 of the first emitter body 130, respectively. Yes. The second decompression groove 200 has a plurality of convex portions 231 at the bottom. The discharge hole 210 is disposed so as to penetrate the front surface 141 side and the back surface 142 side of the second emitter body 140 at a position of the second emitter body 140 corresponding to the discharge recess 180 of the first emitter body 130. ing.

  By joining the first emitter body 130 and the second emitter body 140, the first connection groove 160 and the second connection groove 190 are integrated into a connection flow path 220, and the first pressure reduction groove 170 and the second pressure reduction groove 200 are combined. Are integrated into the decompression channel 230, and the discharge recess 180 and the discharge hole 210 are integrated into the discharge unit 240 (see FIG. 5B). Thereby, the flow path which comprises the water intake part 150, the connection flow path 220, the pressure reduction flow path 230, and the discharge part 240, and connects the water intake part 150 and the discharge part 240 is formed. The flow path circulates the irrigation liquid from the water intake unit 150 to the discharge unit 240.

  The water intake unit 150 is disposed on the surface 131 of the first emitter body 130. In the present embodiment, the water intake unit 150 includes two water intake through holes 151 and a plurality of ridges 152.

  The two water intake through-holes 151 are respectively disposed on the outer edge portions on both sides of the surface 131 of the first emitter body 130 along the major axis direction of the first emitter body 130 (see FIG. 3A).

  The shape and number of the water intake through holes 151 are not particularly limited as long as the irrigation liquid can be taken into the first emitter body 130. Since each of the water intake through holes 151 is partially covered by a plurality of ridges 152, the water intake through holes 151 appear to be divided into a large number of through holes when viewed from the surface 131 side ( (See FIG. 3A).

  The plurality of ridges 152 are arranged on the surface 131 of the first emitter body 130 so as to straddle the water intake through hole 151. In the present embodiment, the plurality of ridges 152 are arranged so that the major axis direction of the ridges 152 is along the minor axis direction of the first emitter body 130. The plurality of ridges 152 prevent floating substances in the irrigation liquid introduced into the first emitter body 130 from entering the water intake through hole 151.

  The arrangement and the number of the ridges 152 are not particularly limited as long as the irrigation liquid can be taken in from the intake water through-hole 151 and the intrusion of suspended matter in the irrigation liquid can be prevented. The interval between adjacent ridges 152 is not particularly limited as long as the above-described function can be exhibited.

  The irrigation liquid that has flowed through the tube 110 is taken into the first emitter body 130 while the suspended matter is prevented from entering the water intake through hole 151 by the plurality of ridges 152.

  The connection flow path 220 connects the water intake through hole 151 (water intake section 150) and the pressure reduction flow path 230 (see FIG. 3B). In the present embodiment, the connection flow path 220 is linearly formed along the minor axis direction of the first emitter body 130 on the back surface 132 side of the first emitter body 130 (or the front surface 141 side of the second emitter body 140). Is formed. A decompression channel 230 is connected near the center of the connection channel 220. The connection channel 220 is formed by the first connection groove 160 and the second connection groove 190 by joining the first emitter body 130 and the second emitter body 140 together. The irrigation liquid taken in from the water intake 150 flows through the connection flow path 220 to the decompression flow path 230.

  The decompression flow path 230 connects the connection flow path 220 and the discharge unit 240 (see FIGS. 3B and 4A). The decompression channel 230 reduces the pressure of the irrigation liquid introduced from the water intake unit 150 and guides it to the discharge unit 240. In the present embodiment, the decompression flow path 230 is disposed along the long axis direction at the central portion of the back surface 132 of the first emitter body 130 (or the surface 141 of the second emitter body 140). The upstream end of the decompression flow path 230 is connected to the connection flow path 220, and the downstream end is connected to the discharge unit 240.

  The shape of the decompression channel 230 is a columnar shape (see FIGS. 5B and 5C). The columnar shape includes not only a circular sectional shape perpendicular to the central axis L (in a portion where the convex portion 231 is not disposed) but also an elliptical shape. And the decompression flow path 230 has the some convex part 231 arrange | positioned on one side and the other side on both sides of the central axis L. The convex portions 231 disposed on one side with the central axis L interposed therebetween and the convex portions 231 disposed on the other side are alternately disposed in the flow direction of the irrigation liquid (see FIG. 5B).

  “One side and the other side across the central axis L” include the central axis L and are parallel to the back surface 132 of the first emitter body 130 (or the surface 141 of the second emitter body 140). It may be one side and the other side (horizontal direction) across the central axis L, and includes the central axis L and the back surface 132 of the first emitter body 130 (or the surface 141 of the second emitter body 140). In a cross section perpendicular to the central axis L, one side (for example, the inner wall surface side of the tube 110) and the other side (for example, the central axis side of the tube 110) (vertical direction) may be interposed. In the present embodiment, the plurality of convex portions 231 includes the central axis L and is perpendicular to the back surface 132 of the first emitter body 130 (or the surface 141 of the second emitter body 140) from the viewpoint of facilitating manufacturing. In a simple cross section, they are arranged on one side (for example, the inner wall surface side of the tube 110) and the other side (for example, the center axis side of the tube 110) (vertical direction) with the central axis L interposed therebetween.

  The shape of the convex portion 231 is not particularly limited as long as it can be decompressed while ensuring the flow of the irrigation liquid in the decompression flow path 230. The shape of the convex portion 231 is surrounded by an arc portion along the inner peripheral surface of the decompression flow channel 230 and a chord portion connecting the two ends of the arc portion in a cross section perpendicular to the central axis L of the decompression flow channel 230. It is preferably a curved arc. Examples of arcuate shapes include semicircles. In the present embodiment, since the shape of the decompression flow path 230 is circular in the cross section perpendicular to the central axis L of the decompression flow path 230, the shape of the convex portion 231 is preferably semicircular (see FIG. 5C). ).

  The thickness of the convex portion 231 is not particularly limited, and may change as it goes toward the central axis L of the decompression flow path 230, or may be constant, but decreases as it goes toward the central axis L of the decompression flow path 230. It is preferable to become. If the thickness of the convex portion 231 decreases toward the central axis L of the decompression flow path 230, the tip end portion of the convex portion 231 on one side and the convex portion 231 on the other side across the central axis L of the decompression flow path 230. Therefore, the irrigation liquid can be easily flowed in the vicinity of the central axis L of the decompression flow path 230. The thickness of the convex portion 231 refers to the thickness of the convex portion 231 in a direction parallel to the central axis L of the decompression channel 230 (see FIG. 5B). Further, the tip portion of the convex portion 231 refers to a portion of the convex portion 231 that is not in contact with the inner peripheral surface of the decompression flow path 230.

  The height of the convex portion 231 is not particularly limited, but is preferably a height that does not exceed the central axis L. This is to facilitate the flow of the irrigation liquid in the vicinity of the central axis L of the decompression flow path 230. The height of the convex portion 231 includes the central axis of the decompression flow path 230 and is in a cross section perpendicular to the back surface 132 side of the first emitter body 130 (or the front surface 141 side of the second emitter body 140). Is the maximum height from the inner peripheral surface (see FIG. 5B).

  It is preferable that the convex portion 231 further includes a notch 232 disposed so as to surround the central axis L of the decompression flow path 230 (see FIG. 5C). Thereby, the irrigation liquid can be easily flowed in the vicinity of the central axis L of the decompression flow path 230.

  The shape of the notch 232 is not particularly limited, but may be a semicircular shape or a polygon (such as a triangle or a quadrangle) in a cross section perpendicular to the central axis L of the decompression flow path 230. In the present embodiment, the shape of the notch 232 in the cross section perpendicular to the central axis L of the decompression flow path 230 is a semicircular shape.

  The size of the notch 232 is not particularly limited as long as it does not interfere with the stirring and decompression function of the irrigation liquid by the convex portion 231, but the shortest distance from the central axis L to the edge of the notch 232 is It is preferably 10% or more and 25% or less of the distance from the central axis L to the inner peripheral surface of the decompression flow path 230 (the radius of the decompression flow path 230 in a cross section perpendicular to the central axis L of the decompression flow path 230).

  As described above, the decompression flow path 230 is formed by joining the first emitter main body 130 and the second emitter main body 140 so that the first decompression groove 170 having a plurality of protrusions 231 on the bottom and a plurality of protrusions on the bottom. And a second decompression groove 200 having 231 (see FIGS. 5B and 5C).

  The irrigation liquid taken in from the water intake 150 is decompressed by the decompression channel 230 and guided to the discharge part 240.

  The discharge portion 240 is disposed so as to penetrate the second emitter body 140 from the back surface 132 of the first emitter body 130 (see FIGS. 3B, 4A and B, and 5B). The discharge unit 240 sends the irrigation liquid from the decompression flow path 230 to the discharge port 112 of the tube 110. The structure of the discharge part 230 will not be specifically limited if the above-mentioned function can be exhibited. In the present embodiment, the discharge portion 240 is a recess formed by the discharge recess 180 of the first emitter body 130 and the discharge hole 210 of the second emitter body 140. The planar view shape of the recess is not particularly limited, and is, for example, a substantially rectangular shape.

(Operation of drip irrigation tube and emitter)
Next, the operation of the drip irrigation tube 100 will be described. First, irrigation liquid is fed into the tube 110. Examples of irrigation liquids include water, liquid fertilizers, pesticides and mixtures thereof. The pressure of the irrigation liquid fed to the drip irrigation tube 100 is preferably 0.1 MPa or less so that the drip irrigation method can be easily introduced and the tube 110 and the emitter 120 are prevented from being damaged. . The irrigation liquid in the tube 110 is taken from the water intake 150 into the emitter 120 (or the first emitter body 130). Specifically, the irrigation liquid in the tube 110 flows into the water intake through hole 151 from the gap between the adjacent ridges 152. At this time, the water intake section 150 has a plurality of ridges 152 that partially cover the water intake through-holes 151, so that floating substances in the irrigation liquid can be removed.

  The irrigation liquid taken from the water intake unit 150 reaches the connection flow path 220. The irrigation liquid that has reached the connection channel 220 flows into the decompression channel 230.

  The irrigation liquid that has flowed into the decompression flow path 230 flows into the discharge unit 240 while being decompressed. Although details will be described later, in the decompression flow path 230, a vortex flowing while swirling three-dimensionally is generated. The irrigation liquid that has flowed into the discharge unit 240 is discharged out of the tube 110 from the discharge port 112 of the tube 110.

(simulation)
As described above, in the emitter 120 according to the present embodiment, the decompression channel 230 has a cylindrical shape, the plurality of convex portions 231 include the central axis L, and the back surface 132 (or the first surface of the first emitter body 130). In the cross section perpendicular to the surface 141) of the two-emitter body 140, they are arranged on one side and the other side (vertical direction) across the central axis L. A simulation was performed on the action of the pressure reducing channel 230 configured as described above on the flow of the irrigation liquid. For comparison, the decompression flow path 20 has a quadrangular prism shape, the convex portion 18 has a triangular prism shape, and the plurality of convex portions 18 include the central axis L and are parallel to the back surface 11 of the emitter 10. In the cross section, an emitter 10 (hereinafter referred to as “comparative emitter”) configured in the same manner as the emitter 120 according to the present embodiment, except that it is arranged on one side and the other side (horizontal direction) across the central axis L. (Also referred to as).

  FIG. 6 is a perspective view showing a configuration of a comparative emitter. In FIG. 6, in order to make the flow path of the emitter for comparison easier to see, the display is shown upside down and the film 30 is covered on the back surface 11 of the emitter 10. As shown in FIG. 6, the comparative emitter 10 includes a water intake through hole 12, a first connection groove 13, a first pressure reduction groove 14, a second connection groove 15, a second pressure reduction groove 16, and a third pressure reduction groove 17. , Through holes 19, 20 and 21, and a discharge part 22. The first decompression groove 14, the second decompression groove 16, and the third decompression groove 17 are closed by the film 30, and the first decompression channel 24, the second decompression groove 26, and the third decompression channel 27 is formed. The first decompression channel 24, the second decompression groove 26, and the third decompression channel 27 are all rectangular prisms, and a plurality of convex portions 18 project from two opposite side surfaces (horizontal direction). The shape of the convex portion 18 is a triangular prism shape.

  7A and 7B are conceptual diagrams showing the flow of irrigation liquid in the comparative emitter, which is analyzed from the simulation results of the comparative emitter. 7A is a diagram showing the flow of the irrigation liquid when viewed from the direction of arrow 7A in FIG. 6, and FIG. 7B is a cross-sectional view taken along line 7B-7B in FIG. It is a figure which shows the flow of the liquid for irrigation.

As shown in FIGS. 7A and 7B, in the third decompression channel 27 (hereinafter, also simply referred to as “decompression channel”), a part of the irrigation liquid zigzags around the central axis L of the decompression channel. It can be seen that the other part swirls in the space between the adjacent protrusions 18 in the flow direction (see particularly FIG. 7A). It can also be seen that only one flow (spiral stirring flow) swirling in the space between the adjacent convex portions 18 is generated for each space (see FIG. 7A).
Further, the flow of the irrigation liquid flowing near the center line of the decompression flow path and the flow of the irrigation liquid swirling in the space between the adjacent convex portions 18 are both horizontal (flow direction and reduced pressure) in the decompression flow path. Flow in a plane substantially parallel to a plane including the width direction of the flow path (see FIG. 7B), that is, in the emitter 10 for comparison, the irrigation liquid flows two-dimensionally in the reduced pressure flow path. I understand.
As described above, in the comparative emitter 10, the irrigation liquid has only one flow swirling in the space between the adjacent convex portions 18 (spiral stirring flow) for each space, and the pressure is reduced. It can be seen that the stirring effect is not sufficient because the inside of the flow path is only stirred two-dimensionally. As a result, when foreign matter flows between the adjacent convex portions 18, it may not be able to flow out together with the flow near the central axis L of the decompression flow path. Thereby, it is considered that clogging due to foreign matter entering the reduced pressure channel is likely to occur.

  FIG. 8 is a perspective view showing the configuration of the emitter according to the present embodiment. 9A and 9B are conceptual diagrams showing the flow of the irrigation liquid in the emitter according to the present embodiment, analyzed from the simulation result of the emitter according to the present embodiment. 9A is a diagram showing the flow of the irrigation liquid when viewed from the direction of the arrow 9A in FIG. 8, and FIG. 9B is an irrigation flow in the decompression channel 230 in the cross-sectional view taken along the line 9B-9B in FIG. It is a figure which shows the flow of a liquid.

As shown in FIGS. 9A and B, in the emitter 120 according to the present embodiment, part of the irrigation liquid that has flowed into the decompression channel 230 flows in a zigzag manner near the central axis L of the decompression channel. (Not shown) It can be seen that most of the irrigation liquid swirls in the space between the adjacent convex portions 231 in the flow direction.
Moreover, it turns out that the flow (vortex-shaped stirring flow) swirling in the space between adjacent convex parts 231 has generate | occur | produced for every space (refer FIG. 9A). The reason for this is not clear, but is presumed as follows. In a cross section perpendicular to the central axis L of the decompression flow path 230, the irrigation liquid flows along the wall of the cylindrical decompression flow path 230 from both sides in the width direction of the decompression flow path 230 (or the bottom of the decompression flow path 230 (or It flows toward the top. The irrigation liquid traveling from both sides in the width direction of the decompression channel 230 to the bottom (or top) collides at the bottom (or top) of the wall of the columnar decompression channel 230 and is separated from the wall and is centered. Go to axis L. The irrigation liquid exceeding the central axis L is bounced back by the convex portion 231, then again faces the walls on both sides in the width direction of the columnar decompression flow path 230, and again on both sides in the width direction of the decompression flow path 230. It flows along the wall and goes to the bottom (or top) of the decompression flow path 230. This repetition is considered to produce two spiral stirring flows.
Furthermore, the flow of the irrigation liquid (swirled stirring flow) swirling in the space between the adjacent convex portions 231 is substantially parallel to a plane including the vertical direction (the flow direction and the depth direction of the decompression flow path 230). It can be seen that not only in the plane) but also in the horizontal direction (the width direction of the decompression flow path 230), that is, in three-dimensional stirring (see FIG. 9A).
As described above, in the emitter 120 according to the present embodiment, the irrigation liquid has two or more flows swirling in the space between the adjacent convex portions 231 (spiral stirring flow) for each space, and Since the inside of the decompression flow path 230 can be stirred three-dimensionally, it turns out that the stirring effect is high enough. As a result, even if a foreign substance flows between adjacent convex portions 231, it can flow out together with the flow near the central axis L of the decompression flow path. Thereby, it is considered that foreign matter that has entered the decompression flow path 230 can be easily flowed out, and clogging can be made difficult to occur.

(effect)
As described above, in the emitter 120 according to the present embodiment, the decompression channel 230 has a columnar shape and includes the plurality of convex portions 231 disposed on one side and the other side with the central axis L interposed therebetween. Have. Thereby, the inside of the decompression channel 230 can be easily stirred three-dimensionally. Thereby, in the emitter 120 according to the present embodiment, even if foreign matter flows into the reduced pressure channel 230, it can be easily flowed out of the reduced pressure channel 230 due to a high stirring effect, and clogging due to foreign matter occurs. Can be difficult.

(Modification)
In the present embodiment, the plurality of convex portions 231 has a cross section that includes the vertical direction, that is, the center axis L, and is perpendicular to the back surface 132 of the first emitter body 130 (or the surface 141 of the second emitter body 140). However, the present invention is not limited to this example. For example, the plurality of convex portions 231 are arranged in a horizontal direction, that is, in a cross section including the central axis L and parallel to the back surface 132 of the first emitter body 130 (or the front surface 141 of the second emitter body 140) from the central axis L. May be arranged on one side and the other side.

  Further, in the present embodiment, the example in which the convex portion 231 has the notch 232 arranged so as to surround the central axis L of the decompression flow path 230 is shown, but the present invention is not limited thereto, and the notch 232 is provided. You don't have to.

  In the present embodiment, an example in which the cross-sectional shape perpendicular to the central axis L of the decompression flow path 230 is circular is shown, but the present invention is not limited to this, and may be elliptical.

  Further, in the present embodiment, the example in which the decompression flow path 230 is disposed so as to extend linearly in the flow direction of the irrigation liquid is illustrated, but the present invention is not limited thereto, and may be disposed in a meandering manner. And it may be arranged in a U shape.

  ADVANTAGE OF THE INVENTION According to this invention, even if a foreign material flows in into a flow path, it is possible to provide the emitter and drip irrigation tube which can make it hard to produce clogging with a foreign material. Therefore, the spread of the emitter to technical fields that require long-term dripping, such as drip irrigation and durability tests, and further development of the technical field are expected.

DESCRIPTION OF SYMBOLS 100 Drip irrigation tube 110 Tube 112 Discharge port 120 Emitter 131, 141 Front surface 132, 142 Back surface 150 Water intake part 151 Water intake through-hole 152 Projection 160 First connection groove 170 First decompression groove 180 Discharge recess 190 Second connection groove 200 Second decompression groove 210 Discharge hole 220 Connection channel 230 Decompression channel 240 Discharge section

Claims (7)

When the inner wall surface of the tube through which the irrigation liquid is circulated is joined to a position corresponding to the discharge port communicating between the inside and the outside of the tube, the irrigation liquid in the tube is quantitatively measured from the discharge port. An emitter for discharging outside,
A water intake for taking in the irrigation liquid;
A discharge part arranged to face the discharge port, for discharging the irrigation liquid;
A channel for connecting the water intake unit and the discharge unit to distribute the irrigation liquid;
Including
The flow path includes a columnar decompression flow path,
The decompression flow path has a plurality of convex portions arranged on one side and the other side across the central axis,
The convex portions arranged on the one side and the convex portions arranged on the other side are alternately arranged in the flow direction of the irrigation liquid.
Emitter. In a cross section perpendicular to the central axis of the decompression flow path,
The shape of the convex portion is an arcuate shape surrounded by an arc portion along the inner peripheral surface of the decompression flow path and a chord portion connecting two end portions of the arc portion.
The emitter according to claim 1. The thickness of the convex portion decreases as it goes toward the central axis of the decompression flow path.
The emitter according to claim 1 or 2. The convex portion has a notch arranged so as to surround the central axis of the decompression flow path.
The emitter according to any one of claims 1 to 3. The plurality of convex portions are disposed on the inner wall surface side of the tube and the central axis side of the tube across the central axis of the decompression flow path,
The emitter according to any one of claims 1 to 4. The emitter is
A first emitter body having the water intake and a first pressure-reducing groove having a plurality of protrusions on the bottom;
A second emitter body having the discharge portion and a second decompression groove having a plurality of convex portions at the bottom;
Have
The decompression flow path is formed by the first decompression groove and the second decompression groove.
The emitter according to any one of claims 1 to 5. A tube having a discharge port for discharging irrigation liquid;
The emitter according to any one of claims 1 to 6, joined at a position corresponding to the discharge port of the inner wall surface of the tube;
Having a drip irrigation tube.