JP6429577B2 - Emitter and drip irrigation tubes - Google Patents

Description

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

  As one of the plant cultivation methods, drip irrigation is known. In the drip irrigation method, for example, a drip irrigation tube is placed on the soil where plants are planted, and water or liquid fertilizer is slowly supplied from the drip irrigation tube to the soil. is there. The drip irrigation method can minimize the consumption of the irrigation liquid, and has attracted particular attention in recent years.

  Such drip irrigation tubes typically have a tube and an emitter (also referred to as a “dripper”). The emitter normally supplies the irrigation liquid in the space in the tube to the soil at a set speed at which the irrigation liquid is dripped onto the soil. Known emitters are an emitter that is used by piercing a tube from the outside, and an emitter that is joined to the inner wall surface of the tube.

  The latter emitter includes, for example, a flow path including a pressure reducing section for flowing the liquid flowing into the emitter from the space in the tube while reducing the pressure toward the through hole of the tube, and the reduced irrigation liquid in the flow path. And a diaphragm portion that changes the volume of the portion through which the liquid flows according to the pressure of the liquid in the space. The emitter is composed of three parts: a part joined to the inner wall surface of the tube, a part arranged on the part, and a diaphragm portion arranged between both parts. The said diaphragm part is comprised by the film | membrane which has elasticity like a silicone rubber film (for example, refer patent document 1).

  The emitter can suppress variations in the discharge amount of the irrigation liquid regardless of fluctuations in the pressure of the liquid in the space in the tube. Therefore, the emitter is advantageous from the viewpoint of uniformly growing a plurality of plants.

JP 2010-46094 A

  The emitter is constructed by assembling three parts. For this reason, an assembly error may occur in the emitter. In particular, an assembly error related to the diaphragm portion may cause variations in operation of the diaphragm portion, and may cause variations in the discharge amount of the irrigation liquid.

  The emitter is usually a molded product of an inexpensive resin such as polyethylene or polypropylene, but a part of another more expensive material having elasticity, such as a silicone rubber film, is used for the diaphragm portion. The use of such parts of different materials leaves room for study from the viewpoint of reducing material costs.

  Furthermore, in a drip irrigation tube, several hundred emitters may be arranged in one tube. In a long drip irrigation tube, it is necessary to increase the supply pressure of the liquid to the tube. However, if the liquid flows out from the emitter before the pressure of the liquid in the tube is sufficiently increased, the pressure of the liquid in the tube is unlikely to rise, and the amount of liquid discharged from the emitter may not be stable. On the other hand, when the discharge amount of the liquid from the emitter increases as the pressure of the liquid in the tube increases, the discharge amount of the emitter disposed on the upstream side of the tube increases, and the emitter disposed on the further downstream side. May be insufficient. Therefore, appropriate control of the amount of liquid discharged from the emitter in accordance with the pressure of the liquid in the tube is required.

  Furthermore, the flow path in the emitter is generally narrow, and even if a small foreign substance enters the flow path, the amount of liquid discharged from the emitter may be insufficient. For this reason, effective countermeasures against foreign matters in the liquid taken into the emitter and foreign matters entering from the discharge port of the tube are desired. Furthermore, from the viewpoint of reducing the material cost and manufacturing cost of the emitter, there is a demand for an emitter that can be manufactured with a single inexpensive material and with a smaller number of parts.

It is a first object of the present invention to provide an emitter that can stabilize the discharge amount of irrigation liquid and that can further reduce manufacturing costs.
Moreover, this invention makes it the 2nd subject to provide the tube for drip irrigation which has the said emitter.

  The present invention is an emitter composed of a resin molded body having at least a concave portion and a through-hole, and is bonded to a position corresponding to a discharge port communicating with the inside and 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 in the tube from the discharge port, the water intake unit for taking in the irrigation liquid in the tube, and the water intake unit A water intake amount adjusting unit for adjusting the flow rate of the irrigation liquid in accordance with the pressure of the irrigation liquid in the water intake unit, and for flowing the irrigation liquid supplied from the water intake amount adjusting unit while reducing the pressure. A decompression unit, a discharge amount adjusting unit for adjusting a flow rate of the irrigation liquid supplied from the decompression unit according to a pressure of the irrigation liquid in the tube, and the discharge A discharge unit that faces the discharge port to which the irrigation liquid whose flow rate is controlled by the adjustment unit is supplied, and the water intake unit collects suspended matter in the irrigation liquid The screen portion includes a slit that opens to the inside of the tube, and a concave portion that communicates with the slit and extends in a direction intersecting the longitudinal direction of the slit, The discharge part provides an emitter including an intrusion prevention part for preventing intrusion of foreign matter from the discharge port.

  The present invention also provides a drip irrigation tube comprising a tube and the emitter disposed on the tube.

  The emitter according to the present invention controls the inflow amount of the irrigation liquid to the emitter according to the pressure of the irrigation liquid in the drip irrigation tube, so that the discharge amount of the irrigation liquid at the emitter is stabilized. Can do. In addition, since the emitter according to the present invention can be composed of one or two parts by injection molding of a resin material, the manufacturing cost can be further reduced as compared with the conventional three-part emitter. Is possible.

FIG. 1A is a schematic longitudinal sectional view of a drip irrigation tube according to an embodiment of the present invention, and FIG. 1B is a schematic transverse sectional view of the drip irrigation tube. FIG. 2A is a diagram illustrating a plane, a front surface, and a side surface of the emitter according to the above embodiment, and FIG. 2B is a diagram illustrating a bottom surface, a front surface, and a side surface of the emitter. 3A is a plan view of the emitter according to the embodiment, FIG. 3B is a front view of the emitter, and FIG. 3C is a side view of the emitter. FIG. 4A is a bottom view of the emitter according to the above embodiment, and FIG. 4B is a cross-sectional view of the emitter along the line BB in FIG. 3A. FIG. 5A is a diagram illustrating a plane, a front surface, and a side surface of the molded product before the film is bonded to the emitter body in the above embodiment, and FIG. 5B is a diagram illustrating a bottom surface, a front surface, and a side surface of the molded product. is there. FIG. 6A is a plan view of a molded product before the film is bonded to the emitter body in the above embodiment, and FIG. 6B is a bottom view of the molded product. FIG. 7A is an enlarged view of a cross section taken along line DD in FIG. 6A of the emitter when the pressure of the irrigation liquid in the tube is less than a set value according to the above embodiment. FIG. 7B is an enlarged view showing a cross section along the line DD in FIG. 6A of the emitter when the pressure of the irrigation liquid in the tube is equal to or higher than a set value. FIG. 8A is an enlarged view showing an A portion in FIG. 4B of the emitter when the pressure of the irrigation liquid in the tube is equal to or higher than the first set value, according to the above embodiment. FIG. 8C is an enlarged view showing the A portion of the emitter when the pressure in the tube is equal to or greater than a first set value and less than a second set value. FIG. It is a figure which expands and shows the said A part of the said emitter when it is more than the setting value of 2. FIG.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. FIG. 1A is a schematic longitudinal sectional view of a drip irrigation tube according to an embodiment of the present invention, and FIG. 1B is a schematic transverse sectional view of the drip irrigation tube. The drip irrigation tube 100 includes a tube 110 and an emitter 120. The tube 110 is made of, for example, polyethylene.

  The emitters 120 are arranged in the axial direction of the tube 110 at a predetermined interval (for example, 200 to 500 mm). Each emitter 120 is joined to the inner wall surface of the tube 110. The emitter 120 is formed in a shape that can easily adhere to the tube 110. For example, the shape of the surface (second surface to be described later) joined to the inner wall surface of the tube 110 in the cross section cut by the XZ plane of the emitter 120 is such that the tube 110 is along the inner wall surface of the tube 110 at the time of water supply. It has a substantially arc shape protruding toward the inner wall surface. The emitter 120 is disposed at a position covering the discharge port 130 of the tube 110. The X direction indicates the axial direction of the tube 110 or the longitudinal direction of the emitter 120, the Y direction indicates the short (width) direction of the emitter 120, and the Z direction indicates the height direction of the emitter 120. .

  The discharge port 130 is a hole that penetrates the tube wall of the tube 110. The hole diameter of the discharge port 130 is, for example, 1.5 mm. An arrow F indicates the direction in which the irrigation liquid flows in the tube 110.

  FIG. 2A is a diagram illustrating a plane, a front surface, and a side surface of the emitter 120, and FIG. 2B is a diagram illustrating a bottom surface, a front surface, and a side surface of the emitter 120. 3A is a plan view of the emitter 120, FIG. 3B is a front view of the emitter 120, and FIG. 3C is a side view of the emitter 120. 4A is a bottom view of the emitter 120, and FIG. 4B is a cross-sectional view of the emitter 120 along the line BB in FIG. 3A.

  As shown in FIGS. 2A and 2B, the emitter 120 has a housing-like outer shape. The planar shape (the shape viewed along the Z direction) of the emitter 120 is a substantially rectangular shape with each corner rounded and chamfered, and the side surface shape (the shape viewed along the X direction) of the emitter 120 is as described above. Furthermore, it is a shape (bell shape) consisting of a semicircle and a rectangle connected to it. For example, the length of the emitter 120 in the X direction is 26 mm, the length in the Y direction is 10 mm, and the length in the Z direction is 2.5 mm.

  The emitter 120 includes an emitter main body 200 bonded to the inner wall surface of the tube 110 and a film 300 bonded to the emitter main body 200. First, the film 300 will be described.

  The film 300 has a slit 301, a diaphragm portion 302, and a positioning hole 303. The slit 301 is an elongated opening along the X direction. Three slits 301 are arranged in parallel at a position in the film 300 that overlaps a protrusion 213 described later. The thickness of the film 300 is, for example, 0.5 mm.

  Diaphragm portion 302 is a portion of film 300 that should overlap with concave portions 231 and convex portions 232 described later. The thickness of the diaphragm part 302 is the same as the other part of the film 300, and its planar shape is circular. Note that the thickness of the diaphragm 302 can be determined by, for example, computer simulation or a prototype experiment based on the amount of deformation with respect to pressure, which will be described later.

  The positioning holes 303 are two holes that pass through the film 300 and have a circular planar shape, and are arranged at positions corresponding to, for example, a pair of opposing corners on a diagonal line of the film 300.

  Next, the emitter body 200 will be described. FIG. 5A is a diagram illustrating a plane, a front surface, and a side surface of the molded product before the film 300 is bonded to the emitter body 200, and FIG. 5B is a diagram illustrating a bottom surface, a front surface, and a side surface of the molded product. FIG. 6A is a plan view of the molded product, and FIG. 6B is a bottom view of the molded product.

  The emitter body 200 has a first surface 201 and a second surface 202 as shown in FIGS. 5A and 5B. The first surface 201 is one surface in the Z direction that is bonded to the film 300. The second surface 202 is the other surface in the Z direction that is joined to the inner wall surface of the tube 110. The first surface 201 is a flat surface, and the second surface 202 is a non-flat surface having a substantially semicylindrical shape.

  As shown in FIGS. 5A, 6A, and 6B, the emitter body 200 is disposed integrally with the film 300 via a hinge portion 304. The hinge portion 304 is disposed on one side edge of the emitter body 200 on the first surface 201 side in the Y direction. The hinge portion 304 is, for example, a portion having a width of 0.5 mm that has the same thickness as the film 300 and is integrally formed with the emitter body 200 and the film 300.

  As shown in FIGS. 5A and 5B, the emitter body 200 includes a recess 211, a protrusion 213 disposed in the recess 211, a valve body 214 and a fixing portion 215 formed on the bottom surface of the recess 211, And a recess 216 extending from the second surface 202 to the valve body 214 and the fixing portion 215. In addition, the slit 301, the recessed part 211, and the protrusion 213 comprise a water intake part. The valve body 214 and the fixing part 215 constitute a water intake amount adjusting part.

  The planar shape of the recess 211 is a bell shape consisting of a rectangle and a semicircle connected to one side thereof, and the depth of the recess 211 from the first surface 201 is, for example, 0.5 mm. The bell-shaped semicircular portion has a diameter of, for example, 6 mm.

  The ridges 213 are three elongated protrusions arranged in parallel in the Y direction in the longitudinal direction, which are arranged in a rectangular portion in the planar shape of the recess 211. The height from the bottom surface of the recess 211 of the protrusion 213 to the protrusion end surface of the protrusion 213 is, for example, 0.5 mm. There is a gap between the ridges 213 in the X direction or between the ridge 213 and the wall surface of the recess 211, and there is also a gap between the end of the ridge 213 and the wall surface of the recess 211 in the Y direction. As shown in FIG. 4B, the protrusion 213 is formed such that the cross-sectional shape cut along the XZ plane is narrower at the base end than at the protrusion. That is, the gap between the protrusions 213 in the X direction or between the protrusions 213 and the wall surface of the recess 211 increases as the depth of the recess 211 increases. The angle formed by the wall surface of the protrusion 213 with respect to the bottom surface of the recess 211 is, for example, 80 to 84 °. Thus, the protrusion 213 constructs a so-called wedge wire structure in the recess 211.

  Each of the valve body 214 and the fixing portion 215 has a sector shape in which the planar shape is a circular shape divided into four parts, and is arranged alternately along the circumferential direction. The form of the fixing portion 215 is a flat plate, and one surface thereof forms the same plane as the bottom surface of the recess 211. The valve body 214 has a circular arc portion as a fixed end and a radius as a free end, and is disposed at a position recessed from the bottom surface of the concave portion 211 by the thickness of the fixed portion 215. That is, the upstream free edge of the valve body 214 is in contact with the downstream free edge of the fixing portion 215. The valve body 214 and the fixed portion 215 are arranged at a position where any of the free ends intersects the X direction or the Y direction at 45 ° when viewed in plan.

  As shown in FIG. 6B, the valve body 214 includes a flexible thin-walled portion 2141 extending from the fixed end and a thick-walled portion 2142 extending from the thin-walled portion 2141. The thin portion 2141 has a thickness that is uniform from the arc serving as the fixed end and is sufficiently thinner than the fixed portion 215.

  The thick part 2142 is a thick part on the downstream side of the valve body 214. The thick portion 2142 has, for example, a substantially triangular pyramid shape protruding toward the recess 216. The bottom surface shape of the thick portion 2142 is a right isosceles triangle with the center of the fan shape in the valve body 214 as one apex, two wall surfaces standing downstream from the free end, and a downstream side from the oblique side of the right triangle. And an inclined surface extending obliquely. The boundary in the planar shape of the thin part 2141 and the thick part 2142 is a straight line. The top part of the thick part 2142 is slightly cut away so that, for example, the distance from the inner wall surface of the tube 110 to the thick part 2142 is about 0.5 mm when the emitter 120 is joined to the tube 110. Yes.

  As shown in FIG. 5B, the planar shape of the recess 216 is a circle having the same diameter as the semicircular shape of the bell shape of the recess 211, and the bottom thereof is configured by the valve body 214 and the fixing portion 215.

  Further, the emitter body 200 has a recess 221 as shown in FIGS. 5B and 6B. The recess 221 is a groove extending along the X direction on the second surface 202. The concave portion 221 communicates with the concave portion 216 at one end thereof, and the planar shape thereof is substantially rectangular. The depth of the recess 221 from the second surface 202 is, for example, 0.5 mm. The recess 221 includes a reduced pressure channel portion 222 (a reduced pressure portion) and a hole 223.

  The decompression flow path part 222 is a part in which the planar shape is formed in a zigzag groove. The zigzag shape includes convex portions having a substantially triangular prism shape protruding from the side surface of the concave portion 221 and are alternately arranged along the longitudinal direction (X direction) of the concave portion 221. The convex portion is arranged so that the protruding end of the convex portion does not exceed the central axis of the concave portion 221 when viewed in plan. The depth of the decompression flow path portion 222 is, for example, 0.5 mm, and the width of the flow path of the decompression flow path portion 222 (W in FIG. 4A) is, for example, 0.5 mm.

  The hole 223 opens at the other end of the recess 221 and penetrates the emitter body 200.

  The emitter body 200 includes a recess 231, a protrusion 232, an end surface 233, a hole 234, and a groove 235, as shown in FIGS. 5A and 6A. Diaphragm part 302, convex part 232, end face 233, hole 234 and groove 235 constitute a discharge amount adjusting part.

  The recess 231 is a bottomed recess that opens to the first surface 201. The planar shape of the recess 231 is circular, and a hole 234 is opened at the bottom of the recess 231. The circular diameter is 6 mm, for example, and the depth of the recess 231 from the first surface 201 is 2 mm, for example.

  The convex portion 232 is a thick, substantially cylindrical body that stands up from the center of the bottom of the concave portion 231. The height of the convex part 232 is smaller than the depth of the concave part 231. For example, the distance in the Z direction from the first surface 201 to the convex portion 232 is 0.25 mm.

  The end surface 233 is a protruding end surface of the convex portion 232. The planar shape of the end surface 233 is circular, and the diameter thereof is, for example, 3 mm. The end surface 233 includes an outer ring portion 2331 that is parallel to the XY plane, and an inclined surface 2332 that is inclined from the inner peripheral edge of the outer ring portion 2331 toward the center of the end surface 233 toward the second surface 202 (FIG. 8A). .

  The inclined surface 2332 is a curved surface that is slightly recessed with respect to the first surface 201 side. The inclined surface 2332 is formed so as to overlap with an imaginary curve in contact with the opening edge of the recess 231 in the cross section including the central axis of the recess 231. The virtual curve includes a curve drawn by the diaphragm 302 in the cross section when the irrigation liquid in the tube 110 receives a pressure equal to or higher than a set value (FIGS. 8A and 8C). The curve is, for example, a curve having a radius of curvature R of 12 mm. Thus, the inclined surface 2332 is a valve seat portion on which the diaphragm portion 302 can be seated.

  The hole 234 opens at the center of the end surface 233 and penetrates the emitter body 200. The hole 234 is a tapered hole whose diameter gradually increases from the end surface 233 side toward the concave portion 241 side along the Z direction. The opening on the end surface 233 side of the hole 234 is smaller than the opening on the concave portion 241 side, and the hole diameter on the end surface 233 side of the hole 234 is, for example, 1 mm.

  The groove 235 is formed in the end surface 233 and extends from the outer peripheral edge of the end surface 233 to the hole 234. That is, the groove 235 communicates the recess 231 and the hole 234. The number of grooves 235 may be one or more. For example, the width of the groove 235 is 2 mm, and the depth of the groove 235 is 0.05 mm.

  Moreover, the emitter main body 200 has the recessed part 241 and the protrusion 242 as FIG. 5B and FIG. 6B show. The concave portion 241 is a discharge portion that should face the discharge port 130.

  The planar shape of the recess 241 is substantially rectangular. More specifically, the planar shape of the concave portion 241 is an inclined portion that connects the first portion 2411 on the concave portion 221 side in the X direction, the deeper second portion 2412, and the first portion 2411 and the second portion 2412. 2413 and the hole 234 opened to the edge of the first portion 2411 on the concave portion 221 side are combined. Thus, the planar shape of the recess 241 is a shape in which a semicircle by the hole 234 is connected to one side of the rectangle. Both the planar shapes of the first portion 2411 and the second portion 2412 are substantially rectangular. The inclination angle of the inclined portion 2413 with respect to the bottom surface of the second portion 2412 is, for example, 60 °.

  The ridge 242 is disposed on the first portion 2411 along the boundary with the inclined portion 2413. Further, the height of the protrusion 242 is the same as the depth of the first portion 2411. The protrusion 242 is separated from the hole 234 in the X direction. In the Y direction, the length of the protrusion 242 is shorter than the length of the first portion 2411, and both ends of the protrusion 242 are separated from the inner wall surface of the first portion 2411. Thus, the protrusion 242 is disposed so as to completely overlap the hole 234 when viewed from the second portion 2412 side along the X direction.

  Further, the emitter body 200 opens to the second surface 202 as shown in FIGS. 5B and 6B and the convex portion 251 protruding from the first surface 201 as shown in FIGS. 5A and 6A. And a recess 252.

  The planar shape of the convex portion 251 is circular, and has a size that fits into the positioning hole 303 of the film 300. The convex portions 251 are respectively arranged at positions corresponding to the positioning holes 303.

  The recess 252 is disposed between the recess 216 and the recess 241 in the X direction and at a position between the recess 221 and the side edge of the emitter body 200 in the Y direction.

  The emitter body 200 and the film 300 are both formed of one kind of flexible material, for example, polypropylene. Examples of the material include a resin and rubber, and examples of the resin include polyethylene and silicone. The flexibility of the emitter body 200 and the film 300 can be adjusted by using an elastic resin material. For example, the elasticity of a resin material having elasticity relative to the type of resin having elasticity or a hard resin material can be adjusted. It is possible to adjust by the mixing ratio. The integrally molded product of the emitter body 200 and the film 300 can be manufactured by, for example, injection molding.

  The emitter 120 is configured by rotating the film 300 around the hinge portion 304 and joining the film 300 to the first surface 201 of the emitter body 200. For example, the film 300 is bonded to the emitter main body 200 by welding the emitter main body 200 or a resin material constituting the film 300, bonding with an adhesive, pressing the film 300 to the emitter main body 200, or the like. By bonding the film 300 to the first surface 201, the recess 231 is watertightly closed by the diaphragm portion 302 and becomes a part of the flow path of the irrigation liquid in the emitter 120. In this way, a series of the flow paths from the recess 211 to the recess 241 is formed. The hinge part 304 may be left as it is, or may be removed by cutting.

  The drip irrigation tube 100 is configured by joining the emitter 120 to the inner wall surface of the tube 110 at the second surface 202 thereof. The emitter 120 is also bonded to the inner wall surface of the tube 110 by, for example, welding of a resin material constituting the emitter body 200 or the tube 110, adhesion with an adhesive, and pressure bonding of the emitter body 200 to the tube 110. The discharge port 130 is formed so as to open to the second portion 2412 of the emitter 120. The discharge port 130 is usually formed after the emitter 120 is bonded to the tube 110, but may be formed before the bonding.

  Next, the flow of irrigation liquid in the emitter 120 will be described. First, for example, water is supplied as an irrigation liquid into the tube 110. Examples of the irrigation liquid include water, liquid fertilizer, agricultural chemicals, and a mixture thereof. The supply of water to the drip irrigation tube 100 is performed in a range where the water pressure does not exceed 0.1 MPa in order to prevent the tube 100 and the emitter 120 from being damaged. The water in the tube 110 passes through the slit 301 of the film 300 and passes through the gap between the recess 211 and the protrusion 213.

  Since the longitudinal direction of the slit 301 and the longitudinal direction of the ridge 213 intersect each other, the openings of the recesses 211 with respect to the tube 110 are dotted and the area of each opening is small. Therefore, the penetration | invasion to the recessed part 211 of the suspended matter in the water in the tube 110 is suppressed. As described above, the slit 301, the protrusion 213, and the concave portion 211 also constitute a screen portion for collecting suspended matters in water taken into the emitter 120 from the inside of the tube 110. Moreover, since the protrusion 213 constructs a so-called wedge wire structure, the pressure loss of the water flowing into the recess 211 is suppressed.

  The water in the recess 211 reaches the position of the valve body 214 and the fixed portion 215 in the recess 211. FIG. 7A is an enlarged view showing a cross section taken along the line DD in FIG. 6A of the emitter 120 when the pressure of water in the tube 110 is less than a set value, and FIG. It is a figure which expands and shows the cross section along the DD line in FIG. 6A of the emitter 120 when the pressure of the water in 110 is more than a setting value. The arrows in FIGS. 7A and 7B represent the flow of water.

  The water in the recessed portion 211 presses the valve body 214 and the fixing portion 215 from the recessed portion 211 side toward the recessed portion 216 side. When the water pressure in the concave portion 211 is less than a set value (for example, 0.005 MPa), as shown in FIG. 7A, the valve body 214 and the fixing portion 215 do not bend toward the concave portion 216, and the water flow path. Is closed by the valve body 214 and the fixing portion 215.

  When the water pressure in the recess 211 is equal to or higher than the set value, as shown in FIG. 7B, the thin portion 2141 is thinner than the fixed portion 215, so that the fixed portion 215 does not bend but only the thin portion 2141 is bent, and the fixed portion Although 215 does not open to the recessed part 216 side, only the valve body 214 opens to the recessed part 216 side. Thus, a gap is formed between the valve body 214 and the fixed portion 215, and the water in the recess 211 is supplied to the recess 216 through the gap.

  The water in the recess 216 is supplied to the decompression flow path part 222 through the recess 221. The water flowing through the decompression flow path part 222 is decompressed by the pressure loss caused by the planar shape (zigzag shape) of the decompression flow path part 222. Further, the suspended matter in the water is caught in the turbulent flow generated between the convex portions of the decompression flow path portion 222 and stays in the decompression flow path portion 222. In this way, the suspended matter is further removed from the water by the decompression flow path section 222.

  The water that has been depressurized through the depressurizing flow path portion 222 and from which the suspended matter has been removed is supplied into the recess 241 through the hole 223.

  Here, FIG. 8A is an enlarged view showing a portion A in FIG. 4B when the water pressure in the tube 110 is equal to or higher than the first set value, and FIG. 8B shows the water pressure in the tube 110 being the first. FIG. 8C is an enlarged view of the A portion when the set value is less than the second set value and less than the second set value, and FIG. 8C shows the A portion when the water pressure in the tube 110 is greater than or equal to the second set value. FIG.

  When the water fills the recess 241, the water is supplied to the hole 234 through the gap between the film 300 and the end surface 233, as shown in FIG. 8A. If the water pressure in the tube 110 is equal to or higher than a first set value (for example, 0.02 MPa), the flow rate of water in the water intake section increases as the water pressure in the tube 110 increases and is supplied to the recess 231. The amount of water also increases.

  On the other hand, when the water pressure in the tube 110 becomes equal to or higher than the first set value, the diaphragm portion 302 is pushed by the water pressure in the tube 110 and bent toward the concave portion 231 as shown in FIG. 8B. For this reason, the space | interval of the diaphragm part 302 and the end surface 233 becomes narrow. For example, the distance from the end surface 233 to the diaphragm portion 302 is 0.15 mm. Therefore, the amount of water flowing through the gap between the end surface 233 and the diaphragm portion 302 is reduced.

  When the pressure of the irrigation liquid in the tube 110 becomes equal to or higher than a second set value (for example, 0.05 MPa), as shown in FIG. 8C, the diaphragm portion 302 is further bent by being pressed by the concave portion 231 side. 2332. The hole 234 is closed by the diaphragm portion 302, while the end surface 233 includes the groove 235, so that the groove 235 communicates the recess 231 and the hole 234. For this reason, the water in the recess 231 is supplied from the recess 231 to the hole 234 through the groove 235. For this reason, at the time of high water pressure, the flow rate of water in the hole 234 is regulated to a constant flow rate that can pass through the groove 235.

  The water that has passed through the hole 234 is supplied to the recess 241. That is, water that has passed through the hole 234 is first supplied to the first portion 2411, and then supplied to the second portion 2412 through the gap between the inner wall surface of the recess 241 and the protrusion 242. The water supplied to the second portion 2412 flows out of the tube 110 through the discharge port 130 opening in the second portion 2412. The ridge 242 is disposed at a position that is on a straight line connecting the hole 234 and the discharge port 130 when the emitter 120 is joined to the tube 110, and the flow of water from the hole 234 to the discharge port 130 is I'm detouring. Thus, the protrusion 242 is a rectifying member that controls the flow of water in the recess 241 as described above.

  When the drip irrigation tube 100 is used, it is conceivable that the roots of the plant seek water and enter the recess 241 from the discharge port 130. Such intrusion of foreign matter is blocked by the protrusion 242. Therefore, the hole 234 is prevented from being blocked by the foreign matter. As described above, the discharge unit includes an intrusion prevention unit (protrusion 242) that prevents intrusion of foreign matter from the discharge port 130.

  As is clear from the above description, the emitter 120 is formed of a resin molded body having at least a recess and a through-hole, and is joined to a position corresponding to the discharge port 130 on the inner wall surface of the tube 110 so as to be within the tube 110. An emitter for quantitatively discharging irrigation liquid (water) from the discharge port 130, and a water intake portion for taking in water in the tube 100, and a flow rate of water taken from the water intake portion in the water intake portion The water intake amount adjusting unit for adjusting according to the water pressure of the water, the pressure reducing channel portion 222 for flowing the water supplied from the water intake amount adjusting portion while reducing the pressure, and the water supplied from the pressure reducing channel portion 222 The discharge amount adjustment unit for adjusting the flow rate of the water according to the water pressure in the tube 110 and the discharge port 130 to which water whose flow rate is controlled by the discharge amount adjustment unit is supplied The intake section includes a screen section for collecting the suspended matter in the water, and the screen section communicates with a slit 301 that opens into the tube 110 and the slit 301. And a recess that is a gap between the protrusions 213 and between the protrusions 213 and the wall surface of the recess 211, extending in a direction intersecting with the longitudinal direction of the slit 301, An intrusion prevention unit for preventing intrusion of foreign matter from 130 is included.

  Thus, since the emitter 120 includes the water intake amount adjustment unit and the discharge amount adjustment unit, the discharge amount of the water in the tube 110 from the emitter 120 is stabilized according to the water pressure in the tube 110. Can do.

  In addition, since the emitter 120 has the above-described screen portion, it is possible to prevent floating substances in the water in the tube 110 from entering the emitter 120. Since the emitter 120 has the intrusion prevention portion, the emitter 120 can Intrusion of foreign matter into the emitter 120 can be prevented. For this reason, water can flow stably in the emitter 120 at a desired flow rate.

  In addition, the film 300 having the slits 301 that intersect with the protrusions 213 in the concave portion 211 when viewed in plan is effective for easily forming a large number of inlets of the flow paths in the emitter 120 with a small area. Also, it is more effective from the viewpoint of preventing the floating matter in the tube 110 from entering the emitter 120.

  Furthermore, since the above-described components of the emitter 120 in the emitter body 200 are formed by the recesses and the through holes formed in the emitter body 200, the emitter body 200 including these components is integrally formed by injection molding. Can be produced. Therefore, the cost for manufacturing the emitter 120 can be further reduced as compared with a conventional emitter having three parts.

  In addition, the fact that the screen portion includes a so-called wedge wire structure in which the width of the concave portion increases as the depth of the concave portion increases is that the screen portion on the downstream side of the screen portion when foreign matter is collected. This is even more effective from the viewpoint of suppressing pressure loss.

  Further, the water intake amount adjustment unit includes a valve body 214 that protrudes from a fixed end in the flow path in the emitter 120 and opens to the downstream side under the pressure of water on the upstream side, and the valve body 214 extends from the fixed end. When the water pressure on the upstream side with respect to the water intake amount adjusting unit is equal to or higher than a set value, the flexible thin-walled portion 2141 and the thick-walled portion 2142 extending from the thin-walled portion 2141 are projected. When the portion 2141 is bent and the valve body 214 opens to the downstream side, it is possible to stop the inflow of water into the emitter 120 when the water pressure in the tube 110 is low. As a result, water from the discharge port 130 can be stopped. It is possible to stop the outflow. Therefore, it is much more effective from the viewpoint of stabilizing the discharge amount of water in the tube 110 by maintaining the pressure in the tube 110 sufficiently and quickly.

  Further, the planar shape of the boundary between the thick part 2142 and the thin part 2141 is a linear shape, and the thick part 2142 is a thick part on the downstream side of the valve body 214. This means that the valve body 214 is opened downstream. This is more effective from the viewpoint of facilitating and setting the set value for opening / closing the valve body 214 to be smaller or opening / closing the valve body 214 more precisely.

  Further, the water intake amount adjusting portion further has a fixing portion 215 disposed at a position adjacent to the valve body 214 when viewed in plan, and the planar shapes of the valve body 214 and the fixing portion 215 are all fan-shaped. When the valve bodies 214 and the fixing portions 215 are alternately arranged in the circumferential direction when viewed in plan, it is more effective from the viewpoint of increasing the productivity of the emitter body 200 by injection molding.

  In addition, the discharge amount adjusting section blocks the communication between the flow path downstream of the decompression flow path section 222 and the inside of the tube 110, and has a flexible film 300 and the downstream side of the decompression flow path section 222. An end surface 233 that is disposed in a non-contact manner facing the film 300 and can be in close contact with the film 300, and is recessed with respect to the film 300, and a hole 234 that opens to the end surface 233 and is connected to the discharge unit The film 300 has a groove 235 that is formed in the end surface 233 and communicates the flow path outside the end surface 233 and the hole 234, and the film 300 is in close contact with the end surface 233 when the water pressure in the tube 110 is equal to or higher than a set value. This prevents excessive outflow of water from the emitter 120 when the water pressure in the tube 110 is high, and stabilizes at a desired amount from the emitter 120 without depending on the water pressure in the tube 110. It is more effective in terms of discharging the water.

  In addition, the fact that the end surface 233 includes the inclined surface 2332 to which the diaphragm portion 302 deformed by the water pressure in the tube 110 can closely contact is further effective from the viewpoint of stably discharging water from the emitter 120 in an intended amount. It is.

  The discharge unit includes a hole 234 for supplying the water to the discharge unit, and the intrusion prevention unit is on a straight line connecting the hole 234 and the discharge port 130 when the emitter 120 is joined to the tube 110. The ridge 242 (rectifying member) that is disposed at a position that bypasses the flow of water from the hole 234 to the discharge port 130 is further enhanced from the viewpoint of preventing the root of the plant from entering the emitter 120. It is effective.

  Further, the emitter 120 is formed of one kind of flexible material, and the film 300 is integrally formed as a part of the emitter 120. This means that both the emitter body 200 and the film 300 are injection molded. Therefore, it is more effective from the viewpoints of preventing manufacturing errors due to the bonding position of the film 300 and further reducing manufacturing costs.

  In addition, it is more effective from the viewpoint of increasing the bonding strength of the emitter 120 to the inner wall surface of the tube 110 that the cross-sectional shape in the YZ plane of the second surface 202 of the emitter body 200 is a substantially arc shape.

  In addition, the fact that the film 300 has the positioning hole 303 and the emitter body 200 has the convex portion 251 can easily and accurately join the film 300 to the intended position, increase the productivity, and improve the quality due to manufacturing errors. This is even more effective from the viewpoint of suppressing variations.

  In addition, the emitter body 200 having the concave portion 252 (thickening hole) is more effective from the viewpoint of increasing the molding accuracy of the emitter body 200, increasing the productivity, and ensuring the desired quality.

  Further, the valve body 214 and the fixed portion 215 are both fan-shaped, adjacent to each other, and the upstream free end edge of the valve body 214 is in contact with the downstream free end edge of the fixed portion 215. Further, the fact that the fixing portion 215 is disposed does not require cutting of the valve body 214 and the fixing portion 215, so that both the valve body 214 and the fixing portion 215 are molded at a time only by injection molding. It is effective.

  In addition, the concave portion 241 includes the shallower first portion 2411 on the upstream side and the deeper second portion 2412 on the downstream side. The root of the plant is further upstream from the discharge port 130. It is effective from the viewpoint of preventing intrusion into the ridge, and it is even more effective from the above viewpoint that the protrusion 242 is further disposed in the first portion 2411.

  In addition, in the range where the above-mentioned effect is produced, a part of the above-described constituent requirements of the drip irrigation tube 100 or the emitter 120 may be changed, and the drip irrigation tube 100 or the emitter 120 may be other constituent requirements. May further be included.

  For example, the tube 110 may be a seamless tube or a tube formed by joining elongated sheets along the longitudinal direction.

  The discharge port 130 may be a gap formed so as to communicate the inside and outside of the tube 110 with the joint portion of the sheet, or a pipe sandwiched between the sheets at the joint portion. Further, the shape of the discharge port in the axial direction may not be a straight line. In the example of the tube having the discharge port, a depression having an intended shape to be a flow path is formed on the surface of the sheet, and the discharge port that is the flow path is formed in the bonded portion by joining the sheet. A constructed tube.

  Moreover, although the emitter 120 is arrange | positioned so that the said water intake part may be located in the upstream of the flow direction of the water in the tube 110, you may arrange | position so that the said water intake part may be located in the downstream. Further, the directions of the plurality of emitters in one tube 110 may be the same or different.

  Further, the resin material of the emitter body 200 and the resin material of the film 300 may be the same or different.

  The emitter body 200 is integrally formed by resin injection molding, but the emitter body 200 may be composed of two parts, a part on the first surface 201 side and a part on the second surface 202 side. Good. In this case, the film 300 is integrally formed on the component on the first surface 201 side. By configuring the emitter body 200 with the two parts as described above, a flow path such as the decompression flow path can be disposed inside the emitter body 200. In addition, you may shape | mold the said 2 parts integrally through a hinge part.

  In addition, the screen portion includes a plurality of parallel slits 301 and a plurality of parallel recesses extending in a direction intersecting the longitudinal direction of the slits 301. The number of the slits 301 and the recesses is the same. May be one. Moreover, although the said screen part contains the wedge wire structure, it does not need to contain the said structure. For example, the protrusion 213 may stand upright from the bottom of the recess 211.

  Moreover, although the said water intake adjustment part is comprised by the valve body 214 and the fixing | fixed part 215, the valve body 214 and the fixing | fixed part 215 do not need to be arrange | positioned alternately in a plane direction (circumferential direction). Alternatively, the fixing portion 215 may not be included and the valve body 214 may be included. Moreover, the valve body 214 should just be a valve body which opens moderately more than the set water pressure, for example, may be a slice of uniform thickness.

  Moreover, the said water intake amount adjustment part may be comprised by the other structure. For example, the water intake amount adjustment unit includes a portion that separates the concave portion 211 and the concave portion 216, and a plurality of pores that penetrate the portion or convex portions such as burrs that stand up at the opening end of the pore and the upstream side. It may be. Even with such a configuration, it is possible to appropriately adjust the water intake amount according to the water pressure on the upstream side of the water intake adjustment portion.

  Further, the pressure reducing unit only needs to be able to moderately reduce the pressure of water to be supplied to the discharge amount adjusting unit. For example, the planar shape may be a linear flow path, or The flow path area may change depending on the water pressure in the tube 110. Further, the decompression section may be a groove on the first surface 201 covered with the film 300 in the emitter body 200.

  In the present embodiment, the valve seat portion is an inclined surface 2332 that forms a concave surface portion that can be in close contact with the diaphragm portion 302. A suitable form may be sufficient, for example, a plane part may be sufficient.

  In the discharge amount adjusting unit, the diaphragm unit 302 directly opens and closes the flow path (hole 234) in the emitter 120, but the diaphragm unit 302 includes a lid arranged to open and close the flow path in the emitter 120. The structure which opens and closes by approaching and separating from a lid | cover may be sufficient. Also by such a discharge amount adjusting unit, it is possible to appropriately adjust the discharge amount according to the water pressure in the tube 110.

  The intrusion prevention unit may not be the rectifying member as long as it can block the entry of roots and the like from the discharge port 130 into the hole 234. For example, the intrusion prevention unit may be a lattice or a screen arranged at the same position as the rectifying member, or is arranged so as to guide the invading root from the discharge port 130 to the side opposite to the hole 234. It may be a baffle plate.

  Note that the second surface 202 may be a flat surface.

  According to the present invention, it is possible to easily provide an emitter capable of dropping the liquid at an appropriate speed depending on the pressure of the liquid to be dropped. 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 120 Emitter 130 Outlet 200 Emitter main body 201 1st surface 202 2nd surface 211,216,221,231,241,252 Recess 213,242 Projection 214 Valve body 215 Fixing part 222 Decompression Flow path part 223, 234 Hole 232, 251 Protruding part 233 End face 235 Groove 300 Film 301 Slit 302 Diaphragm part 303 Positioning hole 2141 Thin part 2142 Thick part 2331 Outer ring part 2332 Inclined surface 2411 First part 2412 Second part 2413 Inclined part

Claims (9)

The tube is an emitter composed of a resin molded body having at least a recess and a through-hole, and is joined to a position corresponding to a discharge port that communicates the inside and 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 the discharge port,
A water intake for taking in the irrigation liquid in the tube;
A water intake amount adjusting unit for adjusting the flow rate of the irrigation liquid taken from the water intake unit according to the pressure of the irrigation liquid in the water intake unit;
A decompression unit for flowing the irrigation liquid supplied from the water intake adjustment unit while decompressing;
A discharge amount adjusting unit for adjusting the flow rate of the irrigation liquid supplied from the decompression unit according to the pressure of the irrigation liquid in the tube;
A discharge unit to be supplied to the discharge port, to which the irrigation liquid whose flow rate is controlled by the discharge amount adjusting unit is to be supplied, and
The water intake part includes a screen part for collecting suspended matter in the irrigation liquid,
The screen portion includes a slit that opens to the inside of the tube, and a protrusion that extends in a direction that intersects the longitudinal direction of the slit while communicating with the slit , and between the protrusion and the protrusion and the recess. A recess that is a gap between the wall surface of
The discharge unit includes an intrusion prevention unit that prevents intrusion of foreign matter from the discharge port.
Emitter. The emitter according to claim 1, wherein a gap between the width protrusions of the recess or a gap between the protrusion and the wall surface of the recess increases as the depth of the recess increases. The water intake amount adjustment unit includes a valve body that protrudes from a fixed end in the flow path of the irrigation liquid in the emitter and opens to the downstream side under the pressure of the irrigation liquid on the upstream side,
The valve body has a flexible thin-walled portion protruding from the fixed end, and a thick-walled portion extending from the thin-walled portion,
The emitter according to claim 1 or 2, wherein when the pressure of the irrigation liquid upstream of the water intake amount adjustment unit is equal to or higher than a set value, the thin-walled portion is bent and the valve body is opened downstream. The planar shape of the boundary between the thick part and the thin part is a linear shape,
The thick part is a thick part on the downstream side of the valve body,
The emitter according to claim 3. The water intake amount adjusting unit further includes a fixing unit arranged at a position adjacent to the valve body when viewed in plan,
The planar shapes of the valve body and the fixed portion are both fan-shaped,
The valve body and the fixing portion are alternately arranged in the circumferential direction when viewed in plan,
The emitter according to claim 3 or 4. The discharge amount adjusting unit is
A flexible film disposed so as to block communication between the flow path downstream of the decompression section and the inside of the tube;
A valve seat part that is disposed in a non-contact manner facing the film and is in close contact with the flow path downstream of the decompression part, and is recessed with respect to the film,
A hole that opens in the valve seat portion and that leads to the discharge portion;
A groove that is formed in the valve seat portion and communicates the channel and the hole outside the valve seat portion;
Have
The film adheres to the valve seat when the pressure of the irrigation liquid in the tube is equal to or higher than a set value.
The emitter according to any one of claims 1 to 5. The emitter is molded from one kind of flexible material,
The film is integrally molded as part of the emitter,
The emitter according to claim 6. The discharge unit includes a supply port for supplying the irrigation liquid to the discharge unit,
The intrusion prevention unit is disposed at a position on a straight line connecting the supply port and the discharge port when the emitter is joined to the tube, and the irrigation liquid from the supply port to the discharge port It is a rectifying member that bypasses the flow of
The emitter according to any one of claims 1 to 7.   A drip irrigation tube comprising a tube and the emitter according to any one of claims 1 to 8 disposed on the tube.

Images