JP2018174788A - Emitter and drip irrigation tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an emitter that can suppress generation of a siphon phenomenon, and can appropriately discharge irrigation liquid even if the pressure of irrigation liquid in a tube is low.SOLUTION: An emitter has a water intake part, a discharge part, a flow channel, and a seal water housing part. The water intake part takes in irrigation liquid. The discharge part discharges the irrigation liquid. The flow channel connects the water intake part and the discharge part, and allows the irrigation liquid to circulate. The seal water housing part is arranged in the flow channel, and houses seal water.SELECTED DRAWING: Figure 1

Description

  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. One of the advantages of the drip irrigation method is that irrigation liquid consumption can be minimized.

  The drip irrigation tube has a tube in which a plurality of through holes are formed, and a plurality of emitters (also referred to as “droppers”) joined to the inner wall surface of the tube and quantitatively discharging the irrigation liquid from each through hole. (See, for example, Patent Document 1). The irrigation liquid is sent, for example, by a pump into a tube, and is discharged from the through hole to the outside of the tube via the emitter.

  The emitter described in Patent Document 1 includes a first member, a second member, and a membrane member disposed between the first member and the second member. The first member has a water intake for taking in the irrigation liquid into the emitter, and a wall portion disposed inside the first member so as to surround the water intake. The second member has a discharge port for discharging the irrigation liquid out of the emitter. By laminating the first member, the membrane member and the second member in this order, there is a flow path through which the flow irrigation liquid can move between the first member and the membrane member and between the second member and the membrane member. It is formed. The membrane member is formed with a through hole for moving the liquid taken into the emitter from the water intake port from the flow path between the first member and the membrane member to the flow path between the second member and the membrane member It is done.

  Moreover, in the emitter described in Patent Document 1, the water intake is blocked by the membrane member contacting the wall. In the emitter, when the pressure of the irrigation liquid in the tube reaches a predetermined value or more, the membrane member closing the water intake is pressed and deformed by the irrigation liquid. The irrigation liquid flows into the emitter through the gap created between the membrane member and the wall due to the deformation of the membrane member.

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 placed at a position where the height difference is lower, the amount of discharge of irrigation liquid from the emitter at a lower position is higher compared to the amount of discharge of irrigation liquid from the emitter at a higher position . As a result, the pressure in the tube at the high position is negative. As a result, fluid such as air or water containing fine soil from the outside of the tube may flow back to the flow path of the emitter. As described above, the backflow phenomenon (hereinafter also referred to as “siphon phenomenon”) that may occur due to the negative pressure in the tube may contaminate the inside of the emitter or cause clogging.

  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 occurrence of the siphon phenomenon can be suppressed. However, in the emitter described in Patent Document 1, when the pressure in the tube is too low, the water intake is blocked by the membrane member, and there is a problem that the irrigation liquid can not be discharged properly.

  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 connects the inside and outside of the tube in the inner wall of the tube which distributes the liquid for irrigation. And an emitter for quantitatively discharging the irrigation liquid in the tube from the outlet to the outside of the tube, the emitter being disposed on the first surface For taking in the liquid for the liquid, and the discharge part for discharging the liquid for irrigation, which is disposed on the second surface, and connects the water collecting part and the discharge part for circulating the liquid for irrigation It has a channel, and a sealing water storage part which is arranged in the channel and is for storing sealing water.

  In order to solve the above problems, the drip irrigation tube according to the present invention is joined to a tube having a discharge port for discharging an irrigation liquid, and a position corresponding to the discharge port on the inner wall surface of the 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.

1A and 1B are cross-sectional views showing an example of the configuration of a drip irrigation tube according to the embodiment. FIGS. 2A to 2C are diagrams showing the configuration of an emitter or an emitter body according to an embodiment. FIG. 3 is a diagram showing the configuration of the emitter according to the embodiment. FIGS. 4A to 4C are schematic cross-sectional views for explaining the operation of the flow rate reduction unit. FIGS. 5A and 5B are views showing an example of the configuration of a cover and a film integrally formed according to the first modification. 6A and 6B are diagrams showing an example of the configuration of a cover and a film integrally molded product according to the second modification.

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

[Drip irrigation tube and emitter configuration]
FIGS. 1A and 1B are cross-sectional views showing an example of a configuration of a drip irrigation tube 100 according to the present embodiment. FIG. 1A is an axial sectional view of the drip irrigation tube 100, and FIG. 1B is a sectional view of the drip irrigation tube 100 in a direction perpendicular to the axial direction. The drip irrigation tube 100 has a tube 110 and an emitter 120.

  The tube 110 is a tube for flowing irrigation liquid. The irrigation liquid is, for example, pumped into the tube 110 using a pump. A plurality of discharge ports 112 for discharging the irrigation liquid to the outside of the tube 110 at a predetermined interval (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 pass through. In the present embodiment, the diameter of the opening of the discharge port 112 is 1.5 mm. Emitters 120 are respectively bonded 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 material of the tube 110 is not particularly limited. In the present embodiment, the material of the tube 110 is polyethylene.

  Examples of irrigation liquids include water, liquid fertilizers, pesticides and mixtures thereof.

  FIGS. 2A to 2C are diagrams showing the configuration of the emitter 120 or the emitter body 121 according to the present embodiment. 2A is a plan view of the emitter body 121, FIG. 2B is a plan view of the emitter 120, and FIG. 2C is a bottom view of the emitter 120. FIG. 3 is a diagram showing the configuration of the emitter 120 according to the present embodiment. FIG. 3 is a cross-sectional view taken along a line AA shown in FIG. 2B.

  As shown in FIG. 1A, 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 closely contact the inner wall surface of the tube 110 and cover the discharge port 112. In the present embodiment, the shape of the back surface of the emitter 120 joined to the inner wall surface of the tube 110 in a cross section in the direction perpendicular to the axial direction of the tube 110 is the inner wall surface of the tube 110 so that it follows the inner wall surface of the tube 110 It is a substantially arc shape convex toward. The plan view shape of the emitter 120 is a substantially rectangular shape whose four corners are R-chamfered. The size of the emitter 120 is not particularly limited. In the present embodiment, the length in the long side direction of the emitter 120 is 25 mm, the length in the short side direction is 8 mm, and the height is 2.5 mm.

  The emitter 120 according to the present embodiment is configured by at least an emitter body 121, a film 122, and a cover 123. Details of the function of the emitter 120 will be described later.

  The emitter body 121 (emitter 120) has a first surface 1211 and a second surface 1212 that are in a front-to-back relationship. In the present embodiment, the first surface 1211 is located on the front surface side (irrigation liquid side) of the emitter 120, and the second surface 1212 is located on the back surface side (tube 110 side) of the emitter 120.

  Recesses, grooves, protrusions and through holes are appropriately formed in the emitter body 121 within the range where the effects of the present embodiment can be obtained. Although details will be described later, in the present embodiment, at least a water intake recess 153, a flow rate reduction recess 161, and a backflow prevention recess 171 are formed on the first surface 1211 of the emitter main body 121 (FIG. 2A). reference). Further, at least a first connection groove 131, a first decompression groove 132, a second connection groove 133, a second decompression groove 134, and a discharge recess 181 are formed on the second surface 1212 of the emitter body 121 (see FIG. 2C).

  The emitter body 121 may be formed of a flexible material, or may be formed of a rigid material. Examples of the material of the emitter body 121 include resin and rubber. Examples of such resins include polyethylene and silicone. The flexibility of the emitter body 121 can be adjusted by the use of an elastic resin material. Examples of the method of adjusting the flexibility of the emitter main body 121 include selection of a resin having elasticity, adjustment of a mixture ratio of a resin material having elasticity with respect to a hard resin material, and the like. The emitter body 121 can be manufactured, for example, by injection molding.

  The film 122 is bonded to a part of the first surface 1211 of the emitter body 121. The film 122 is disposed on the emitter body 121 so as to close the opening of the flow rate reducing recess 161. That is, the film 122 is bonded to the emitter body 121 at a portion outside the opening. The film 122 is flexible and is deformed by the pressure of the irrigation liquid.

  The shape and size of the film 122 can be appropriately set according to the shape and size of the emitter main body 121 and the shape and size of the opening of the flow rate reduction recess 161 formed in the emitter main body 121. The thickness of the film 122 can be appropriately set according to the desired flexibility.

  The film 122 is formed of a flexible resin material. The material of the film 122 can be appropriately set according to the desired flexibility. Examples of such resins include polyethylene and silicone. The flexibility of the film 122 can also be adjusted by the use of an elastic resin material. An example of the method of adjusting the flexibility of the film 122 is the same as the method of adjusting the flexibility of the emitter body 121. The film 122 can be manufactured, for example, by injection molding.

  The emitter body 121 and the film 122 may be integral or separate. For example, the emitter body 121 and the film 122 may be integrally formed through the hinges, respectively. The film 122 may be bonded to the first surface 1211 of the emitter main body 121 by rotating the film 122 about the hinge portion. The bonding method of the emitter body 121 and the film 122 is not particularly limited. Examples of the bonding method include welding of resin materials, adhesion with an adhesive, and the like. The hinge portion may be cut after the emitter body 121 and the film 122 are joined.

  The cover 123 is joined to a part of the first surface 1211 of the emitter 121 main body. The cover 123 is disposed on the emitter body 121 so as to close the opening of the backflow preventing recess 171. That is, the cover 123 is joined to the emitter body 121 at a portion outside the opening. The shape and size of the cover 123 can be appropriately set according to the shape and size of the emitter main body 121, the shape and size of the opening of the backflow preventing recess 171 formed in the emitter main body 121, and the like.

  A protrusion 124 is formed on one surface of the cover 123. The ridges 124 are arranged to project toward the backflow preventing recess 171 formed in the emitter main body 121. Further, as shown in FIG. 3, the ridges 124 are disposed at positions corresponding to the grooves 172 which are disposed on the bottom surface of the backflow preventing recess 171 in the cover 123. Specifically, the ridges 124 are disposed in the ridges 172 so as to be separated from the inner surface of the ridges 172 and extend along the ridges 172. In other words, the ridges 124 extend in a direction transverse to the flow direction of the irrigation liquid. A gap is formed between the convex streaks 124 and the concave streaks 172. The gap constitutes a part of the flow path through which the irrigation liquid can move.

  Although the details will be described later, a liquid (sealing water) for blocking the flow path can be accommodated between the ridges 124 and the ridges 172. The position, shape, size and number of the ridges 124 are not particularly limited as long as sealing water can be accommodated between the ridges 124 and the grooves 172, and are appropriately set according to the shapes and sizes of the grooves 172. It can be done. Examples of the shape of the ridges 124 include a cylindrical shape and a rectangular tube shape. In the present embodiment, the shape of the ridges 124 is cylindrical. In the present embodiment, the number of ridges 124 is two. The two ridges 124 are arranged concentrically.

  The cover 123 may be formed of a flexible material or may be formed of a rigid material. Examples of the material of the cover 123 include resin, rubber and metal. Examples of such resins include polyethylene and silicone. The flexibility of the cover 123 is the same as the method of adjusting the flexibility of the emitter body 121. The cover 123 can be manufactured, for example, by injection molding. From the viewpoint of suppressing the deformation of the cover 123 due to the pressure of the irrigation liquid and keeping the size of the gap (a part of the flow path) between the convex streak 124 and the concave streak 172 constant, the cover 123 Preferably, it is formed of a rigid material. In the present embodiment, the cover 123 is formed of a rigid material.

  In the present specification, “a material having rigidity” means a material having a rigidity that does not cause a member formed of the material to be deformed by the pressure of the irrigation liquid. For example, when the cover 123 is formed of a rigid material, the above-mentioned material means a material having a rigidity such that the distance between the ridges 124 and the grooves 172 is not substantially changed by the pressure of the irrigation liquid. Do.

  The emitter body 121 and the cover 123 may be integral or separate. The example of the bonding method of the emitter body 121 and the cover 123 is the same as the example of the bonding method of the emitter body 121 and the film 122.

  The film 122 and the cover 123 may be integral (refer to later-described first and second modifications) or may be separate. When the film 122 and the cover 123 are integral, both the film 122 and the cover 123 have flexibility. In the present embodiment, the film 122 and the cover 123 are separate. From the viewpoint of imparting rigidity to the cover 123, the film 122 and the cover 123 are preferably separate.

  The drip irrigation tube 100 is manufactured by joining the back surface of the emitter 120 to the inner wall surface of the tube 110. The method of bonding the tube 110 and the emitter 120 is not particularly limited. Examples of the bonding method include welding of the resin material constituting the emitter 120 or the tube 110, adhesion with an adhesive, and the like. Although the discharge port 112 is usually formed after bonding the tube 110 and the emitter 120, it may be formed before bonding.

  The emitter 120 includes a water intake portion 150, a first connection flow path 141, a first pressure reduction flow path 142, a second connection flow path 143, a second pressure reduction flow path 144, a flow amount reduction portion 160, a backflow prevention portion 170, and a discharge portion 180. Have. The water intake portion 150, the flow rate reduction portion 160 and the backflow prevention portion 170 are disposed on the surface of the emitter 120 (the first surface 1211 of the emitter main body 121). In addition, the first connection flow channel 141, the first pressure reduction flow channel 142, the second connection flow channel 143, the second pressure reduction flow channel 144, and the discharge unit 180 are provided on the back surface of the emitter 120 (the second surface 1212 of the emitter main body 121). It is arranged.

  As the emitter 120 and the tube 110 are joined to each other, the water intake portion 150, the first connection flow channel 141, the first pressure reduction flow channel 142, the second connection flow channel 143, the second pressure reduction flow channel 144, the flow amount reduction section 160, The backflow prevention unit 170 and the discharge unit 180 are formed. Further, in the emitter 120, a flow path connecting the water intake portion 150 and the discharge portion 180 is also formed. The flow path circulates the irrigation liquid from the water intake unit 150 to the discharge unit 180.

  The water intake 150 takes in the irrigation liquid into the emitter 120. The water intake 150 is disposed in about half the area of the first surface 1211 of the emitter body 121 (see FIGS. 2A and 2B). The water intake portion 150 has a water intake side screen portion 151 and a water intake through hole 152.

  The intake side screen unit 151 prevents the floating matter in the irrigation liquid to be taken into the emitter 120 from entering the emitter 120. The water intake side screen portion 151 is open to the inside of the tube 110, and has a water intake recessed portion 153, a plurality of slits 154, and a plurality of screen convex portions 155.

  The water intake recess 153 is a recess formed in a region where the film 122 is not bonded in the first surface 1211 of the emitter main body 121. The depth of the water intake recess 153 is not particularly limited, and is appropriately set according to the size of the emitter 120. A plurality of slits 154 are formed on the outer peripheral wall of the water intake recess 153, and a plurality of screen ridges 155 are formed on the bottom surface of the water intake recess 153. Further, a water intake through hole 152 is formed on the bottom surface of the water intake recess 153.

  The plurality of slits 154 connect the inner side surface of the water intake recess 153 to the outer side surface of the emitter main body 121, and the irrigation liquid is taken into the water intake recess 153 from the side surface of the emitter main body 121. Floats are prevented from entering the water intake recess 153. The shape of the slit 154 is not particularly limited as long as the above-described function can be exhibited. In the present embodiment, the shape of the slit 154 is formed to increase in width from the outer surface of the emitter main body 121 toward the inner surface of the water intake recess 153 (see FIGS. 2A and 2B). As described above, since the slit 154 is configured to have a so-called wedge wire structure, the pressure loss of the irrigation liquid flowing into the water intake recess 153 is suppressed.

  The plurality of screen ridges 155 are disposed on the bottom surface of the water intake recess 153. The arrangement and the number of the screen ridges 155 are not particularly limited as long as the irrigation liquid can be taken in from the opening side of the water intake recess 153 and the entry of suspended solids in the irrigation liquid can be prevented. In the present embodiment, the plurality of screen ridges 155 are arranged such that the major axis direction of the screen ridges 155 is along the minor axis direction of the emitter 120. In addition, the screen ridges 155 are formed such that the width decreases from the first surface 1211 of the emitter main body 121 toward the bottom surface of the water intake recess 153. That is, in the arrangement direction of the screen ridges 155, the space between the adjacent screen ridges 155 has a so-called wedge wire structure. Further, the distance between the adjacent screen ridges 155 is not particularly limited as long as the above-described function can be exhibited. As described above, since the space between the adjacent screen ridges 155 is configured to have a so-called wedge wire structure, the pressure loss of the irrigation liquid flowing into the water intake recess 153 is suppressed.

  The water intake through hole 152 is formed on the bottom surface of the water intake recess 153. The shape and number of the water intake through holes 152 are not particularly limited as long as the irrigation liquid taken into the water intake recess 153 can be taken into the emitter body 121. In the present embodiment, the water intake through hole 152 is one long hole formed along the long axis direction of the emitter 120 on the bottom surface of the water intake recess 153. Since this long hole is partially covered by the plurality of screen ridges 155, when viewed from the first surface 1211 side, the water intake through hole 152 is divided into a large number of through holes. appear.

  The irrigation liquid flowing in the tube 110 is taken into the emitter main body 121 while the intake side screen unit 151 prevents the floating matter from entering the intake recess 153.

  The first connection flow channel 141 (first connection groove 131) is disposed in the flow channel, and includes the water intake portion 150 (water intake through hole 152) and the first pressure reduction flow channel 142 (first pressure reduction groove 132). Connecting. The first connection channel 141 (first connection groove 131) is linearly arranged along the long axis direction of the emitter 120 at the outer edge of the second surface 1212 of the emitter body 121. By joining the tube 110 and the emitter 120, the first connection channel 141 is formed by the first connection groove 131 and the inner wall surface of the tube 110. The irrigation liquid taken in from the water intake portion 150 flows through the first connection flow channel 141 to the first pressure reduction flow channel 142.

  The first pressure reduction channel 142 (first pressure reduction groove 132) is disposed downstream of the first connection channel 141 in the flow channel, and the first connection channel 141 (first connection groove 131) and the second connection flow The path 143 (second connection groove 133) is connected. The first pressure reduction flow path 142 reduces the pressure of the irrigation liquid taken in from the water intake portion 150 and leads it to the second connection flow path 143. The first depressurization channel 142 (first depressurization groove 132) is linearly arranged along the long axis direction of the emitter 120 at the outer edge of the second surface 1212 of the emitter body 121. In the present embodiment, the upstream end of the first decompression channel 142 is connected to the first connection channel 141, and the downstream end of the first decompression channel 142 is connected to the upstream end of the second connection channel 143. ing.

  The shape of the first pressure reducing groove 132 is not particularly limited as long as it can exhibit the above-described function. In the present embodiment, the plan view shape of the first decompression groove 132 is a zigzag shape. In the first decompression groove 132, substantially triangular prism-shaped first projections 1361 protruding from the inner side surface are alternately arranged along the flow direction of the irrigation liquid. The first convex portion 1361 is arranged such that the tip does not exceed the central axis of the first decompression groove 132 when viewed in plan. When the tube 110 and the emitter 120 are joined to each other, the first pressure reducing channel 132 is formed by the first pressure reducing groove 132 and the inner wall surface of the tube 110. The irrigation liquid taken in from the water intake unit 150 is decompressed by the first pressure reduction channel 142 and is guided to the second connection channel 143 (second connection groove 133).

  The second connection flow channel 143 (second connection groove 133) is disposed downstream of the first pressure reduction flow channel 142 in the flow channel, and the first pressure reduction flow channel 142 (first pressure reduction groove 132) and the second pressure reduction It connects with the flow path 144 (second pressure reducing groove 134). The second connection channel 143 is formed in a straight line along the short axis direction of the emitter 120 at the outer edge of the second surface 1212 of the emitter body 121. By joining the tube 110 and the emitter 120, the second connection channel 143 is formed by the second connection groove 133 and the inner wall surface of the tube 110. The irrigation liquid taken in from the water intake portion 150 and guided to the first connection flow channel 141 and reduced in pressure in the first pressure reduction flow channel 142 is conducted to the second pressure reduction flow channel 144 through the second connection flow channel 143. It is eaten.

  The second pressure reduction channel 144 (second pressure reduction groove 134) is disposed downstream of the second connection flow channel 143 in the flow channel, and the second connection groove 133 (second connection flow channel 143) and the flow reduction portion Connect with 160. The second pressure reduction flow path 144 reduces the pressure of the irrigation liquid flowing in from the second connection flow path 143 and leads it to the flow rate reduction unit 160. The second pressure reduction flow path 144 (second pressure reduction groove 134) is disposed at the outer edge of the second surface 1212 of the emitter body 121 along the long axis direction of the emitter 120. The upstream end of the second decompression groove 134 is connected to the downstream end of the second connection groove 133, and the downstream end of the second decompression channel 144 is connected to the first connection through hole 164 of the flow rate reduction portion 160. .

  The shape of the second decompression groove 134 is not particularly limited as long as the above-mentioned function can be exhibited. In the present embodiment, the plan-view shape of the second decompression groove 134 is a zigzag shape similar to the shape of the first decompression groove 132. In the second decompression groove 134, substantially triangular prism-shaped second projections 1362 protruding from the inner side surface are alternately arranged along the direction in which the irrigation liquid flows. The second convex portion 1362 is disposed such that the tip does not exceed the central axis of the second decompression groove 134 in plan view. By joining the tube 110 and the emitter 120, the second decompression channel 144 is formed by the second decompression groove 134 and the inner wall surface of the tube 110. The irrigation liquid taken in from the water intake unit 150 is decompressed by the first depressurization channel 142 and the second depressurization channel 144, and is led to the flow rate reducing unit 160.

  The flow rate reduction portion 160 is disposed upstream of the backflow prevention portion 170 and downstream of the second pressure reduction flow path 144 in the flow path, and is disposed on the surface side of the emitter 120. The flow rate reduction unit 160 sends the irrigation liquid to the backflow prevention unit 170 while reducing the flow rate of the irrigation liquid according to the deformation of the film 122 due to the pressure of the irrigation liquid in the tube 110.

  The configuration of the flow rate reducing unit 160 is not particularly limited as long as the above-described function can be exhibited. In the present embodiment, the flow rate reducing portion 160 has a flow rate reducing recess 161, a valve seat portion 162, a communication groove 163, a first connection through hole 164, a second connection through hole 165, and a diaphragm portion 166.

  The flow rate reducing recess 161 is disposed on the first surface 1211 of the emitter body 121. The plan view shape of the flow rate reducing recess 161 is not particularly limited, and is, for example, a substantially circular shape. The depth of the flow rate reducing recess 161 is not particularly limited, and may be equal to or greater than the depth of the communication groove 163. A first connection through hole 164 and a second connection through hole 165 are opened on the inner surface of the flow rate reduction recess 161. In the present embodiment, the first connection through hole 164 and the second connection through hole 165 are opened at the bottom of the flow rate reducing recess 161.

  The valve seat portion 162 is disposed on the bottom surface of the flow rate reducing recess 161. In the present embodiment, the valve seat portion 162 is disposed in non-contact with the diaphragm portion 166 so as to surround the opening of the second connection through hole 165. The valve seat portion 162 is configured such that when the pressure of the irrigation liquid flowing through the tube 110 exceeds the set value, the diaphragm portion 166 can be in close contact. When the diaphragm portion 166 contacts the valve seat portion 162, the flow rate of the irrigation liquid flowing from the flow rate reducing recess 161 into the backflow preventing portion 170 is reduced.

  The shape of the valve seat portion 162 is not particularly limited as long as the above-mentioned function can be exhibited. In the present embodiment, the valve seat portion 162 is a cylindrical convex portion. In the present embodiment, the height of the end face of the convex portion from the bottom surface of the flow rate reducing recess 161 decreases from the inside toward the outside.

  The communication groove 163 communicates the inside of the flow rate reducing recess 161 with the second connection through hole 165 surrounded by the valve seat portion 162. The communication groove 163 is disposed in part of the surface of the valve seat portion 162 to which the diaphragm portion 166 can be closely attached.

  The first connection through hole 164 is in communication with the upstream side of the flow path in the flow rate reducing portion 160. In the present embodiment, the first connection through hole 164 is in communication with the second pressure reducing channel 144 (second pressure reducing groove 134). The first connection through hole 164 is disposed on the inner surface of the flow rate reduction recess 161. The first connection through hole 164 is disposed, for example, on the bottom or side of the flow rate reduction recess 161. In the present embodiment, the first connection through hole 164 is disposed on the bottom surface of the flow rate reducing recess 161 in a region where the valve seat portion 162 is not disposed.

  The second connection through hole 165 is in communication with the downstream side of the flow path in the flow rate reducing portion 160. In the present embodiment, the second connection through hole 165 communicates with the backflow prevention portion 170. The second connection through hole 165 is disposed on the inner surface of the flow rate reduction recess 161. The second connection through hole 165 is disposed, for example, on the bottom or side of the flow rate reduction recess 161. In the present embodiment, the second connection through hole 165 is disposed in the central portion of the bottom surface of the flow rate reduction recess 161.

  The positions of the first connection through holes 164 and the second connection through holes 165 are not limited to the aspect of the present embodiment. For example, instead of the first connection through hole 164, a second connection through hole 165 may be disposed outside the valve seat portion 162. Further, instead of the second connection through hole 165, the first connection through hole 164 may be disposed so as to be surrounded by the valve seat portion 162.

  The diaphragm portion 166 is a part of the film 122. The diaphragm portion 166 is arranged to block the communication between the inside of the flow rate reducing recess 161 and the inside of the tube 110 and to close the opening of the flow rate reducing recess 161. The diaphragm portion 166 is flexible and deforms to be in contact with the valve seat portion 162 according to the pressure of the irrigation liquid in the tube 110. For example, when the pressure of the irrigation liquid flowing in the tube 110 exceeds the set value, the diaphragm portion 166 is distorted toward the flow rate reduction recess 161 side. Specifically, as the pressure of the irrigation liquid increases, the diaphragm portion 166 deforms toward the valve seat portion 162 and eventually contacts the valve seat portion 162. Even when the diaphragm portion 166 is in close contact with the valve seat portion 162, the diaphragm portion 166 does not close the first connection through hole 164, the second connection through hole 165, and the communication groove 163. The irrigation liquid from the connection through hole 164 may be sent to the backflow prevention unit 170 through the communication groove 163 and the second connection through hole 165.

  The backflow prevention unit 170 is disposed downstream of the flow rate adjustment unit 160 and upstream of the discharge unit 180 in the flow path, and is disposed on the surface side of the emitter 120. The backflow prevention unit 170 sends the irrigation liquid to the discharge unit 180 and prevents the fluid, which flows back from the discharge unit 180 back to the flow path when the liquid feeding is stopped, from flowing upstream of the backflow prevention unit 170.

  From the viewpoint of suppressing the contamination of the inside of the flow path in the component for adjusting the discharge amount from the emitter 120 or the occurrence of clogging by the fluid flowing back from the discharge unit 180 into the flow path, reverse flow prevention It is preferable that the part 170 is arrange | positioned in the downstream of the flow path. That is, the backflow prevention unit 170 is preferably disposed downstream of the component for adjusting the discharge amount from the emitter 120, and is more preferably disposed at a position in direct communication with the ejection unit 180. In the present embodiment, since the backflow prevention unit 170 is disposed downstream of the flow rate adjustment unit 160, the fluid that has flowed back into the flow path does not flow into the flow rate adjustment unit 160.

  The configuration of the backflow prevention unit 170 is not particularly limited as long as the above-described function can be exhibited. In the present embodiment, the backflow prevention portion 170 includes the backflow prevention concave portion 171, the concave streak 172, the third connection through hole 173 (referred to as a “first through hole” in the claims), the fourth It has a through hole for connection 174 (referred to in the claims as a “second through hole”), a sealing water accommodating portion 175 and a ridge 124.

  The backflow preventing recess 171 is disposed on the first surface 1211 of the emitter body 121. The plan view shape of the backflow preventing concave portion 171 is not particularly limited, and is, for example, a substantially circular shape. The depth of the backflow preventing recess 171 is not particularly limited. A third connection through hole 173, a fourth connection through hole 174, and a concave streak 172 are opened on the inner surface of the backflow preventing recess 171. In the present embodiment, the third connection through hole 173, the fourth connection through hole 174, and the concave streak 172 are opened at the bottom surface of the backflow preventing recess 171.

  The recess 172 is open at the bottom of the flow passage and extends in a direction transverse to the flow direction of the irrigation liquid. The concave streaks 172 are arranged to open toward the first surface 1211 of the emitter main body 121 on the bottom surface of the backflow preventing concave portion 171. That is, the concave streak 172 has a bottom on the second surface 1212 side of the emitter main body 121. Further, in the present embodiment, the concave streaks 172 are arranged so as to surround the opening of the fourth connection through hole 174. As described above, the concave streaks 172 are arranged such that the outer surface of the convex streak 124 and the inner surface of the backflow preventive concave section 171 are separated from each other. That is, the concave streaks 172 are arranged such that a gap is formed between the concave streaks 172 and the convex streaks 124. Thus, the flow rate of the irrigation liquid flowing from the flow rate reducing recess 161 to the discharge unit 180 can be secured.

  The position, shape, size and number of the concave streaks 172 are not particularly limited as long as sealing water can be accommodated between the convex streaks 124 and the concave streaks 172, and are appropriately set according to the shape and size of the convex streaks 124 It can be done. Examples of the shape of the concave streaks 172 include a cylindrical shape and a rectangular tube shape. In the present embodiment, the concave streaks 172 are cylindrical concave portions. In the present embodiment, the number of concave streaks 172 is two. The two concave streaks 172 are arranged concentrically.

  The third connection through hole 173 communicates with the upstream side of the flow path in the backflow prevention unit 170. In the present embodiment, the third connection through hole 173 communicates with the flow rate reducing portion 160. The third connection through hole 173 is disposed on the inner surface of the backflow preventing recess 171. The third connection through hole 173 is disposed, for example, on the bottom surface or the side surface of the backflow preventing recess 171. In the present embodiment, the third connection through hole 173 is disposed on the bottom surface of the backflow preventing recess 171.

  The fourth connection through hole 174 communicates with the downstream side of the flow passage in the backflow prevention unit 170. In the present embodiment, the fourth connection through hole 174 communicates with the discharge portion 180. The fourth connection through hole 174 is disposed on the inner surface of the backflow preventing recess 171. The fourth connection through hole 174 is disposed, for example, on the bottom surface or the side surface of the backflow prevention recess 171. In the present embodiment, the fourth connection through hole 174 is disposed in the central portion of the bottom surface of the backflow preventing recess 171.

  The positions of the third connection through hole 173 and the fourth connection through hole 174 are not limited to the aspect of the present embodiment. For example, instead of the fourth connection through hole 174, the third connection through hole 173 may be disposed so as to be surrounded by the concave streaks 172.

  The ridge 124 is a part of the cover 123 and is disposed in the recess 172 so as to be separated from the inner surface of the recess 172. The distance between the ridges 124 and the ridges 172 (the shortest distance) is sufficient as long as the flow rate of the irrigation liquid to the discharge part 180 can be secured and a sufficient amount of sealing water can be accommodated. The interval may be appropriately changed according to the size of the emitter 120, the desired flow rate of the irrigation liquid, and the like.

  Sealed water storage unit 175 stores sealed water. In the present embodiment, the sealing water accommodating portion 175 is configured by the concave streaks 172 and the convex streaks 124. As described above, the ridges 124 are disposed in the ridges 172 so as to be separated from the inner surface of the ridges 172. Thereby, the liquid (sealing water) is accommodated between the concave streaks 172 and the convex streaks 124 so as to interrupt the flow path halfway.

  The discharge unit 180 discharges the irrigation liquid to the outside of the emitter 120. The discharge portion 180 is disposed on the second surface 1212 side of the emitter main body 121 so as to face the discharge port 112 of the tube 110. The discharge unit 180 sends the irrigation liquid in the emitter 120 to the discharge port 112 of the tube 110. Thus, the discharge unit 180 can discharge the irrigation liquid to the outside of the emitter 120. The configuration of the discharge unit 180 is not particularly limited as long as the above-described function can be exhibited. In the present embodiment, the discharge portion 180 has a discharge concave portion 181 and an intrusion prevention portion 182.

  The discharge recess 181 is disposed on the second surface 1212 of the emitter body 121. The plan view shape of the discharge concave portion 181 is a substantially rectangular shape. The fourth connection through hole 174 and the intrusion prevention portion 182 are disposed on the bottom surface of the discharge concave portion 181.

  The entry prevention unit 182 prevents entry of foreign matter from the discharge port 112. The intrusion prevention unit 182 is not particularly limited as long as the function described above can be exhibited. In the present embodiment, the intrusion prevention portion 182 is four convex portions disposed adjacent to each other. The four convex portions are disposed so as to be located between the fourth connection through hole 174 and the discharge port 112 when the emitter 120 is joined to the tube 110.

[Operation of tube for drip irrigation]
Next, the operation of the drip irrigation tube 100 will be described.

  First, the irrigation liquid is fed into the tube 110. The pressure of the irrigation liquid sent 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 breakage of the tube 110 and the emitter 120 can be prevented. . The irrigation liquid in the tube 110 is taken into the emitter 120 from the water intake 150. Specifically, the irrigation liquid in the tube 110 enters the water intake recess 153 from the slit 154 or the gap between the screen ridges 155 and passes through the water intake through hole 152. At this time, since the water intake portion 150 has the water intake side screen portion 151 (the gap between the slit 154 and the screen ridge portion 155), suspended matter in the irrigation liquid can be removed. Further, since a so-called wedge wire structure is formed in the water intake portion 150, the pressure loss of the irrigation liquid flowing into the water intake portion 150 is suppressed.

  The irrigation liquid taken in from the water intake portion 150 reaches the first connection channel 141. The irrigation liquid that has reached the first connection channel 141 passes through the first pressure reduction channel 142 and reaches the second connection channel 143. The irrigation liquid that has reached the second connection channel 143 flows into the second pressure reduction channel 144. The irrigation liquid that has flowed into the second pressure reduction flow path 144 flows into the flow rate reduction portion 160 through the first connection through hole 164. The irrigation liquid flowing into the flow rate reducing portion 160 flows into the backflow preventing portion 170 through the second connection through hole 165 and the third connection through hole 173. The irrigation liquid flowing into the backflow prevention unit 170 flows into the discharge unit 180 through the fourth connection through hole 174. The irrigation liquid flowing into the discharge unit 180 is discharged from the discharge port 112 of the tube 110 to the outside of the tube 110.

(Operation of flow reduction part)
Here, the operation of the flow rate reducing unit 160 according to the pressure of the irrigation liquid in the tube 110 will be described. 4A to 4C are schematic cross-sectional views for describing the operation of the flow rate reduction unit 160. FIG. 4A to 4C are partially enlarged cross-sectional views taken along the line AA shown in FIG. 2B. FIG. 4A is a cross-sectional view in the case where the irrigation liquid is not fed to the tube 110, and FIG. 4B is a cross-sectional view in the case where the pressure of the irrigation liquid in the tube 110 is the first pressure. FIG. 4C is a cross-sectional view in the case where the pressure of the irrigation liquid in the tube 110 is a second pressure exceeding the first pressure.

  In the flow rate reducing portion 160, the flow rate of the irrigation liquid is controlled by deforming the diaphragm portion 166 so as to be distorted toward the flow rate reducing recess 161 in accordance with the pressure of the irrigation liquid in the tube 110. In the present embodiment, since the cover 123 is made of a rigid material, it is not deformed by the pressure of the irrigation liquid.

  Since the pressure of the irrigation liquid is not applied to the film 122 before the irrigation liquid is fed into the tube 110, the diaphragm portion 166 is not deformed (see FIG. 4A).

  As irrigation fluid begins to flow into the tube 110, the diaphragm portion 166 begins to deform (see FIG. 4B). However, when the diaphragm portion 166 is not in contact with the valve seat portion 162, the irrigation liquid taken in from the water intake portion 150 passes through the flow path in the emitter 120 and is made to the outside from the discharge port 112 of the tube 110. It is discharged. As described above, when the delivery of the irrigation liquid into the tube 110 starts, or when the pressure of the irrigation liquid in the tube 110 is lower than the predetermined pressure, the irrigation taken from the water intake 150 into the emitter 120 is performed. The liquid is discharged to the outside through the flow path.

  When the pressure of the irrigation liquid in the tube 110 further increases, the diaphragm portion 166 further deforms toward the valve seat portion 162. Normally, as the pressure of the irrigation liquid increases, the amount of irrigation liquid flowing through the flow path should increase. However, in the emitter 120 according to the present embodiment, the first pressure reduction flow path 142 and the second pressure reduction By reducing the pressure of the irrigation liquid in the flow path 144 and narrowing the distance between the diaphragm portion 166 and the valve seat portion 162, an excessive increase in the amount of irrigation liquid flowing in the flow path is prevented (see FIG. 4B). Then, when the pressure of the irrigation liquid in the tube 110 is equal to or higher than the predetermined value (second pressure), the diaphragm portion 166 contacts the valve seat portion 162 (see FIG. 4C). Even in this case, since the diaphragm portion 166 does not close the first connection through hole 164, the second connection through hole 165 and the communication groove 163, the irrigation liquid taken in from the water intake portion 150 is the communication groove The air is discharged from the discharge port 112 of the tube 110 to the outside through the air port 163. As described above, when the pressure of the irrigation liquid in the tube 110 is equal to or higher than the second pressure, the flow rate reduction unit 160 contacts the valve seat portion 162 with the diaphragm portion 166 to thereby Suppress the increase in liquid volume.

  As described above, the flow rate reducing unit 160 adjusts the flow rate of the irrigation liquid discharged from the discharge port 112 of the tube 110 according to the deformation of the film 122 due to the pressure of the irrigation liquid in the tube 110. Therefore, the drip irrigation tube 100 according to the present embodiment can discharge a fixed amount of irrigation liquid to the outside of the tube 110 regardless of whether the pressure of the irrigation liquid is low pressure or high pressure.

(Function of backflow prevention unit)
Here, the function of the backflow prevention unit 170 will be described. First, for comparison, an emitter for comparison without the backflow prevention portion 170 will be described. As described above, when the drip irrigation tube is disposed at a position where there is a difference in height, when the transfer of the irrigation fluid into the tube 110 is stopped, the amount of irrigation liquid discharged from the emitter at the high position There is a difference between the amount and the amount of irrigation liquid dispensed from the emitter at a low position. As a result, the inside of the tube 110 is negatively pressured due to the height difference, and as a result, in the drip irrigation tube having the emitter for comparison, fluid such as air or water containing fine soil from the outside of the tube A so-called siphon phenomenon may occur which flows back to the flow path of the emitter.

  On the other hand, the emitter 120 which concerns on this Embodiment has the backflow prevention part 170 containing the sealing water accommodating part 175. FIG. When the liquid transfer of the irrigation liquid into the tube 110 is stopped, the irrigation liquid is contained as sealing water in the sealing water storage portion 175. Thereby, in the emitter 120, the flow passage on the upstream side of the sealing water container 175 and the flow passage on the downstream side of the sealing water container 175 are blocked by sealing water. As a result, it is possible to prevent the fluid such as air or water containing fine soil and the like present outside the tube 110 from flowing upstream of the sealing water storage portion 175.

(effect)
As mentioned above, the emitter 120 which concerns on this Embodiment has the sealing water accommodating part 175 for accommodating sealing water. Thus, the emitter 120 can suppress the occurrence of the siphon phenomenon, and can appropriately discharge the irrigation liquid even if the pressure of the irrigation liquid in the tube 110 is low. 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 can be suppressed even in a place having a difference in height, and the inside of the tube can be suppressed. Even when the pressure of the irrigation liquid is low, the irrigation liquid can be discharged quantitatively.

[Modification]
In the above embodiment, the aspect in which the film 122 and the cover 123 are separate has been described, but in the present invention, the film and the cover may be integral.

  FIGS. 5A and 5B are diagrams showing an example of the configuration of the cover and film integral molding 125a according to the first modification. FIG. 5A is a bottom view of the integral molding 125a according to the first modification, and FIG. 5B is a cross-sectional view taken along the line B-B of FIG. 5A. 6A and 6B are diagrams showing an example of the configuration of the cover and film integral molding 125b according to the second modification. FIG. 6A is a bottom view of the integral molding 125b according to the second modification, and FIG. 6B is a cross-sectional view taken along the line B-B of FIG. 6A.

  As shown in FIGS. 5A, B and FIGS. 6A, B, the single-piece moldings 125a, 125b have ridges 124 and diaphragms 166 disposed adjacent to each other. Further, the size and the appearance-viewing shape of the integral moldings 125 a and 125 b may be appropriately changed according to the size of the emitter main body 121. The appearance of the integral molding 125a may be rectangular, and the appearance of the integral molding 125b may be oval.

  Moreover, although the said embodiment demonstrated the aspect which each shape of the convex streak 124 and the concave streak 172 which comprises the sealing water accommodating part 175 is cylindrical shape, of the convex streak 124 which concerns on this invention, and the concave streak 172 The shape may be a rectangular parallelepiped shape, respectively. In this case, the recess 172 is not disposed so as to surround the opening of the fourth connection through hole 174, and is disposed such that both ends of the recess 172 are connected to the side wall surface of the backflow preventing recess 171. ing. For example, when the backflow preventing recess 171 is viewed in plan, the concave streak 172 is opened at the bottom surface of the backflow preventing recess 171, and the opening of the third connection through hole 173 and the fourth connection through hole It is disposed along a direction orthogonal to a virtual line segment connecting the opening 174.

  In addition, the configuration of the emitter and the drip irrigation tube according to the present invention is not limited to the emitter 120 and the drip irrigation tube 100 according to the above-described embodiment. For example, the emitter may be a first decompression channel 142 or a second decompression channel. The flow path 144 and the flow rate adjustment unit 160 may not be provided. In this case, the emitter is constituted by at least the emitter body and the cover.

  Further, in the above embodiment, the first connection flow channel 141, the first pressure reduction flow channel 142, the second connection flow channel 143, and the second pressure reduction flow channel 144 are formed by joining the emitter 120 and the tube 110. The first connection flow channel 141, the first pressure reduction flow channel 142, the second connection flow channel 143, and the second pressure reduction flow channel 144 are formed as flow channels in the emitter 120 in advance. Good.

  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 121 emitter main body 1211 1st surface 1212 2nd surface 122 film 123 cover 124 convex streak 125a, 125b integral molding 131 1st connection groove 132 1st pressure-reduction groove 133 2nd connection Groove 134 Second pressure reduction groove 1361 First convex portion 1362 Second convex portion 141 First connection flow path 142 First pressure reduction flow path 143 Second connection flow path 144 Second pressure reduction flow path 150 Water intake portion 151 Water intake side screen portion 152 Water intake For through hole 153 Water intake recess 154 Slit 155 Screen ridge 160 Flow reduction portion 161 Flow reduction recess 162 Valve seat 163 Communication groove 164 1st connection through hole 165 2nd connection through hole 166 Diaphragm portion 170 Backflow Prevention part 171 Recess prevention recess 172 Concave Article 173 Third connection through hole 174 Fourth connection through hole 175 Sealed water storage unit 180 Discharge unit 181 Discharge recess 182 Intrusion prevention unit

Claims (9)

An inner wall surface of a tube having a first surface and a second surface which are in a relationship of front and back and which circulates an irrigating liquid, is joined at a position corresponding to a discharge port communicating the inside and outside of the tube An emitter for quantitatively discharging the irrigation liquid from the discharge port to the outside of the tube,
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 sealing water storage unit disposed in the flow path and configured to store sealing water;
Have an emitter. The sealed water storage unit is
A recess which is open at the bottom of the flow passage and extends in a direction transverse to the flow direction of the irrigation liquid;
A ridge disposed in the groove so as to be separated from the inner surface of the groove, and extending along the groove;
The emitter according to claim 1, comprising: The emitter is constituted by an emitter body having at least the first surface and the second surface, and a cover joined to the first surface and having the ridges,
The emitter is
A backflow preventing recess disposed on the first surface and having the opening closed by the cover;
A first through hole opened on the inner surface of the backflow preventing recess and in communication with the upstream side of the flow path;
A second through hole opened on the inner surface of the backflow preventing recess and in communication with the discharge portion;
And have
The recess is disposed on the bottom surface of the backflow preventing recess,
The ridges are disposed on the cover so as to protrude toward the backflow preventing concave side.
The emitter according to claim 2.   The emitter according to claim 3, wherein the concave line is disposed to surround an opening of any one of the first through hole and the second through hole. The emitter comprises at least the emitter body, the cover, and a flexible resin film bonded to the first surface.
The emitter is disposed upstream of the sealing water storage unit in the flow path, and reduces the flow rate of the irrigation liquid according to the deformation of the film due to the pressure of the irrigation liquid in the tube. Further having a flow reduction portion of
The emitter according to claim 3 or 4.   The emitter according to claim 5, wherein the cover and the film are separate.   The emitter according to any one of claims 3 to 6, wherein the cover is formed of a rigid material.   The emitter of claim 5, wherein the cover and the film are integral. A tube having a discharge port for discharging the irrigation liquid;
The emitter according to any one of claims 1 to 8, which is joined at a position corresponding to the discharge port on the inner wall surface of the tube.
Having a drip irrigation tube.

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