WO2010140153A1

WO2010140153A1 - Injection molding apparatus for producing drip emitters, and method therefor

Info

Publication number: WO2010140153A1
Application number: PCT/IL2010/000445
Authority: WO
Inventors: Eli Farkash; Shalom Korkus; Arnon Magidess
Original assignee: Plasel Ltd.
Priority date: 2009-06-05
Filing date: 2010-06-06
Publication date: 2010-12-09

Abstract

An injection-molding apparatus and method for producing drip emitters includes feed hopper, injection arrangement including feed barrel, heating element and injection nozzle for delivering the heated feed material, mold arrangement including a stationary mold, a rotating mold having at least two faces, each of the faces adapted to receive the material to form at least one drip emitter base and a drip emitter cover disposed substantially alongside the base, each of the faces rotates into a stop position opposite the stationary mold, a clamping assembly including a moving platen and a support plate adapted to support the platen, a robot assembly including a robot arm, and a gripping unit adapted to grip membrane units, and to effect placement of each of the membrane units within the respective drip emitter bases, and a controller, the robot assembly responsive thereto, the gripping unit places of the membrane units within each base.

Description

Injection Molding Apparatus for Producing Drip Emitters, and Method Therefor

CROSS-REFERENCE TO RELATED APPLICATIONS

This application draws priority from U.S. Provisional Patent Application Serial No. 61/184,536, filed June 5, 2009, which is hereby incorporated by reference in its entirety.

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to injection molding apparatus and methods for producing drip emitters, and more particularly, to such apparatus and methods having a rotating mold assembly.

In injection molding, resin is fed into the machine through the hopper. Colorants, if desired, may be fed to the machine directly after the hopper. The resins enter the injection barrel by gravity though the feed throat. After entering the barrel, the resin is heated to the requisite melting temperature. The injection of the resin into the mold may be effected by a reciprocating screw or by other means known to those skilled in the art of injection molding.

The mold is adapted to receive the plastic and to shape the plastic to a desired, pre-determined shape. The mold is cooled constantly to a temperature that allows the resin to solidify. The mold plates may be held together by hydraulic force or by mechanical force.

We believe there is a need for further improvements in the methods and apparatus for producing drip emitters, and the subject matter of the present disclosure

and claims is aimed at fulfilling this need. SUMMARY OF THE INVENTION

According to the teachings of the present invention there is provided an injection-molding apparatus for producing drip emitters, the apparatus including: (a) a feed arrangement, including at least a first feed hopper, the arrangement adapted to receive a solid feed material; (b) an injection arrangement including: (i) a feed barrel, fluidly communicating with the feed hopper, (ii) at least one heating element, thermally associated with the barrel, and adapted to heat a volume within the barrel, whereby the feed material is transformed into a viscous heated feed material; (iii) an injection nozzle, fluidly communicating with the volume, and (iv) a mechanically-driven delivery mechanism, at least partially disposed within the barrel, and adapted to advance the feed material towards the injection nozzle, and to deliver the heated feed material, at superatmospheric pressure, through the nozzle; (c) a mold arrangement including: (i) a stationary mold; (ii) a mechanically-driven rotating mold, having at least two faces, each having at least one drip emitter cavity set having a plurality of cavity insert pairs, each insert pair including: (A) a drip emitter body cavity insert, and (B) a drip emitter cover cavity insert; the stationary mold and the rotating mold adapted whereby each of the faces rotates into a stop position opposite the stationary mold; (d) a clamping assembly including: (i) a moving platen; (ii) a support plate adapted to support the platen; (iii) at least one tie bar, adapted to guide the platen and the plate, the moving platen and the support plate adapted to move along a longitudinal axis of the tie bar; (e) a robot assembly including at least one robot arm, and a gripping unit adapted to grip a plurality of membrane units, and to effect placement of each of the membrane units within a respective insert of the drip emitter body cavity inserts, and (f) a controller, the injection arrangement, the mechanically-driven rotating mold, and the robot assembly responsive to the controller, whereby, when a first face of the faces is rotated into the position opposite the stationary mold, the injection arrangement injects the heated feed material through the nozzle, and into the plurality of cavity pairs, via the stationary mold, to produce each at least partially filled drip emitter body cavity insert and each at least partially filled drip emitter cover cavity insert, and whereby, when the first face is further rotated, the gripping unit effects the placement of the membrane units within each the at least partially filled drip emitter body cavity insert.

According to another aspect of the present invention there is provided an injection-molding apparatus for producing drip emitters, the apparatus including: (a) a feed hopper adapted to receive a solid feed material; (b) an injection arrangement including: (i) a feed barrel, fluidly communicating with the feed hopper; (ii) at least one heating element, thermally associated with the barrel, and adapted to heat a volume within the barrel, whereby the feed material is transformed into a viscous heated feed material; and (iii) an injection nozzle, through which is delivered the heated feed material, at superatmospheric pressure; (c) a mold arrangement including: (i) a stationary mold; (ii) a mechanically-driven rotating mold, having at least two faces, each of the faces adapted to receive the heated feed material to form at least one drip emitter base and a drip emitter cover disposed substantially alongside the base, the stationary mold and the rotating mold adapted whereby each of the faces rotates into a stop position opposite the stationary mold; (d) a clamping assembly including: (i) a moving platen; (ii) a support plate adapted to support the platen; (iii) at least one tie bar, adapted to guide the platen and the plate, the moving platen and the support plate adapted to move along a longitudinal axis of the tie bar; (e) a robot assembly including a robot arm, and a gripping unit, associated with the arm, and adapted to grip membrane units, and to effect placement of each of the membrane units within a respective one of the at least one drip emitter base, and (f) a controller, the robot assembly responsive to the controller, whereby the gripping unit effects the placement of the membrane units within the respective one of the at least one drip emitter base.

According to yet another aspect of the present invention there is provided an apparatus for producing a drip emitter by means of injection molding, substantially as described herein, the apparatus including any feature described, either individually or in combination with any feature, in any configuration. According to yet another aspect of the present invention there is provided a method of producing a drip emitter by means of injection molding, substantially as described herein, the method including any feature described, either individually or in combination with any feature, in any configuration.

According to another aspect of the present invention there is provided a method of producing drip emitters by means of injection molding, the method including the steps of: (a) providing an injection-molding apparatus for producing drip emitters, as described herein; (b) rotating the rotating mold to bring a first face of the faces into the position opposite the stationary mold; (c) injecting the heated feed material through the nozzle and into the plurality of cavity pairs, via the stationary mold, by means of the injection arrangement, to produce at least partially filled drip emitter body cavity inserts and at least partially filled drip emitter cover cavity inserts; (d) further rotating the rotating mold into a second position, and (e) effecting the placement of the membrane units within the at least partially filled drip emitter body cavity inserts, by means of the gripping unit.

According to further features in the described preferred embodiments, the rotating mold has at least 3 or at least 4 of the faces. According to still further features in the described preferred embodiments, the rotating mold has a substantially cubic or elongated cubic shape.

According to still further features in the described preferred embodiments, the apparatus further includes a membrane delivery system adapted to provide the membrane units to the gripping unit. According to still further features in the described preferred embodiments, the membrane delivery system includes a membrane feed line adapted to provide the membrane units.

According to still further features in the described preferred embodiments, the clamping assembly further includes a driving and locking system adapted to drive the platen and the plate along the at least one tie bar.

According to still further features in the described preferred embodiments, the rotating mold is a substantially vertically rotating mold.

According to still further features in the described preferred embodiments, the apparatus further includes an optical inspection unit disposed and adapted to capture images of an area within the faces of the rotating mold.

According to still further features in the described preferred embodiments, the controller is adapted to receive, after the gripping unit effects the placement of the membrane units within the filled drip emitter body cavity inserts, data pertaining to the images, from the inspection unit, and to determine, from the data, positions of each of the membrane units.

According to still further features in the described preferred embodiments, the controller is adapted to receive data pertaining to the images, from the inspection unit, and to determine, from the data, positions of each of the membrane units in relation to each the respective one of the at least partially filled body cavity inserts.

According to still further features in the described preferred embodiments, the apparatus further includes a flipping mechanism adapted to flip a drip emitter cover from each the filled cover cavity insert to cover each respective membrane unit of the membrane units.

According to still further features in the described preferred embodiments, the apparatus further includes an inspection unit disposed and adapted to ascertain a positioning of each the cover in relation to the respective membrane unit. According to still further features in the described preferred embodiments, the inspection unit includes a sensor.

According to still further features in the described preferred embodiments, the sensor includes a pressure sensor.

According to still further features in the described preferred embodiments, the gripping unit is adapted to simultaneously grip the plurality of membrane units, and wherein the placement of each of the membrane units is a substantially simultaneous placement.

According to still further features in the described preferred embodiments, when one of the faces is disposed in the stop position opposite the stationary mold, the clamping assembly is adapted to urge the moving platen and the support plate along the longitudinal axis to juxtapose the stationary mold and the rotating mold.

According to still further features in the described preferred embodiments, the robot arm includes a rotating or pivoting robot arm.

According to still further features in the described preferred embodiments, the robot arm includes a vertically extending robot arm, associated with, or attached to, the rotating or pivoting arm.

According to still further features in the described preferred embodiments, a vertically extending robot arm is associated with, or attached to, the robot arm, and wherein the gripping unit is associated with, or attached to, the vertically extending robot arm.

According to still further features in the described preferred embodiments, with the rotating mold in the second position, the method further includes the step of: (f) performing step (c) on a second face of the faces.

According to still further features in the described preferred embodiments, the method further includes the step of capturing images of an area within the faces of the rotating mold by means of an optical inspection unit, to determine at least one of: quality of drip emitter bodies in the filled body cavity inserts, quality of drip emitter covers in the filled cover cavity inserts, and membrane positioning.

According to still further features in the described preferred embodiments, the method further includes the steps of further rotating the rotating mold into a third position, and flipping each of the covers, on top of the membrane units, thereby covering each drip emitter body within the partially filled body cavity inserts, to produce the drip emitters.

According to still further features in the described preferred embodiments, the method further includes the steps of further rotating the rotating mold into a third position; flipping each of the covers, on top of the membrane units, thereby covering each drip emitter body within the partially filled body cavity inserts, and fixedly attaching each of the covers to the each drip emitter body, to produce the drip emitters.

According to still further features in the described preferred embodiments, the method further includes the step of inspecting, by means of a sensor disposed in the injection-molding apparatus, a positioning of each of the covers. According to still further features in the described preferred embodiments, the method further includes the steps of further rotating the rotating mold into a fourth position, and ejecting the drip emitters.

According to still further features in the described preferred embodiments, the method further includes the steps of further rotating the rotating mold into a third position; flipping each of the covers, on top of the membrane units, thereby covering each drip emitter body within the partially filled body cavity inserts, to produce the drip emitters, and, in the third position, performing step (e) on the second face.

According to still further features in the described preferred embodiments, the method further includes the step of performing step (c) on a third face of the faces, while the rotating mold remains in the third position. BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of - illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice. Throughout the drawings, like-referenced characters are used to designate like elements.

In the drawings:

Figure IA shows a schematic side view, with hidden lines, of an injection- molding apparatus according to the present invention, the mold being shown in an open position;

Figure IB shows a schematic top view, with hidden lines, of the inventive injection-molding apparatus of Figure IA;

Figure 1C is a schematic, perspective drawing of the inventive injection- molding apparatus of Figure IA;

Figure 2A is a schematic, perspective drawing of a cavity set having a plurality of cavity inserts including drip emitter body cavity inserts and their respective drip emitter cover cavity inserts;

Figure 2B is a schematic, magnified, partial view of Figure 2A, showing two pairs of cavity inserts in greater detail;

Figure 3 provides 13 operating stages of the mold used in conjunction with the apparatus and method of the present invention;

Figure 4A provides a schematic, top perspective view of one embodiment of an exemplary injection-molded drip emitter, manufactured according to the present invention;

Figure 4B provides a cross-sectional view of the drip emitter of Figure 4A;

Figure 5 A provides a schematic, perspective drawing view of the drip emitter of Figure 4A, and

Figure 5B provides a partially cut away view of the drip emitter of Figure 5 A, in which the both the membrane and the snap fit mechanism of the lid are exposed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The principles and operation of the present invention may be better understood with reference to the drawings and the accompanying description.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

Figure IA is a schematic, perspective drawing of an injection-molding apparatus 100 according to the present invention, the mold being shown in an open position. Figure IB is a schematic, top perspective drawing of the injection-molding apparatus of Figure IA.

Injection-molding apparatus 100 includes the following numbered components:

Base 101 Thermoplastic feed hopper 102

Barrel 104

Heater(s) 106

Mechanically-driven delivery mechanism 107

Nozzle 108 Stationary Mold 112

Rotating Mold 120

Cavity Set 121

Stationary Platen 122

Drip Emitter Body Cavity Insert 123 Negative Form of a Drip Emitter Labyrinth 123 A

Moving Platen 124 Mold Plate 125

Side Inspection Unit including Sensor 126

Drip Emitter Cover Cavity Insert 127

Moving Platen Support 128

Clamping Unit 130

Tie Bar 134

Optical Inspection Unit (top) 136

Robot Assembly 140

Rotating Robotic Arm 142

Vertically Extending Robotic Arm 144

Gripping Unit 146

Mold Assembly 150

Membrane Delivery System 160

Membrane (Vibrating) Hopper 161

Membrane Feed Line 162

Controller 180

Injection-molded Drip Emitter 400

Snap Fit Mechanism 402

Drip Emitter Cover 406

Drip Emitter Housing 404

Drip Emitter Membrane Unit 408

Structure and Operation:

The structure and operation of the apparatus of the present invention will be generally familiar to those of ordinary skill in the art of injection molding. Referring now to Figures IA and IB, thermoplastic feed material may be delivered from a feed hopper 102 to a barrel 104. The feed material may be heated in heaters 106 and is then delivered by a mechanically-driven delivery mechanism 107 (which may include, by way of example, a conveying screw and an injecting piston) through a nozzle 108 at high pressure. The heating may be at least partially effected by the shear forces within the injection unit. The heated thermoplastic feed material is introduced to mold assembly 150 via openings in a stationary mold 112 (associated with a stationary platen 122) to a surface or face 129 of a rotating mold 120.

On the opposite side of the rotating mold 120 is disposed a clamping unit or assembly 130 including a moving platen 124, a support plate 128 adapted to support moving platen 124, and at least one tie bar 134 (and most typically, a plurality of tiebars), adapted to guide moving platen 124 and support plate 128, such that platen 124 and plate 128 move along a longitudinal axis of tie bar 134.

Clamping unit or assembly 130 may typically have a drive mechanism (not shown) including a motor or other means known to those skilled in the art, adapted to move platen 124 and plate 128 with respect to tie bar 134. The drive mechanism may be responsive to a controller 180.

To moving platen 124 may be attached a mold plate 125, which may be part of mold assembly 150. Associated with mold plate 125 may be an inspection unit, e.g., a side inspection unit having a sensor 126 (such as a pressure sensor) adapted to detect if a drip emitter cover is securely in place. Membrane delivery system 160 includes a membrane hopper 161, which may be adapted to contain a plurality of membrane units (typically made of silicone), and to deliver membranes to membrane conveyor or feed line 162. The delivery mechanism may be a vibrating mechanism.

A robot assembly 140 may be adapted and configured to transfer a membrane or a plurality of membranes from membrane feed line 162 to a surface of the partially formed emitters disposed in rotating mold 120.

Robot assembly 140 may advantageously be equipped with a rotating robotic arm 142, a vertically extending robotic arm 144, and a gripping unit or assembly 146. Robot assembly 140, including gripping unit 146, and rotating mold 120 may be driven by at least one drive mechanism including motors or other means known to those skilled in the art. Robot assembly 140, gripping unit 146, and rotating mold 120 may be responsive (spatial motion, synchronization) to a controller 180.

Those skilled in the art will appreciate that standard injection molding systems, delivery systems (such as a delivery system having a vibrating hopper) and robot assemblies are commercially available.

Gripping unit 146 may grip or capture a membrane or may simultaneously grip or capture a plurality of membranes, e.g., from membrane feed line 162, and, after appropriate spatial movement by at least one of the robotic arms, release the membranes onto a surface of the at least partially formed emitter bodies disposed in a cavity set on a face of rotating mold 120.

Gripping unit 146 may use vacuum or suction means to capture the individual membranes. Gripping unit 146 may be equipped with individual capturing sites, each one for capturing an individual membrane at a pre-determined or pre-configured location on the bottom surface of the unit. Gripping unit 146 enables multiple (e.g., 2 to 128, more typically, at least 12 to 128) membranes to be gripped by the unit, and to be delivered to rotating mold 120, whereby each membrane is released into a particular location, e.g., within respective cavities or recesses within each of the at least partially formed emitters or emitter bodies.

One method of precisely locating the membranes to be gripped is to adjust the speed of membrane conveyor or feed line 162 such that the membranes are disposed at the requisite intervals or pitch with respect to the membrane openings or recesses in the emitter base. Alternatively, the requisite spacing may be achieved using at least one additional robot arm or gripper.

An optical inspection unit 136, typically disposed above rotating mold 120, may be adapted to inspect a quality of the drip emitter fillings. Following the insertion of the membranes into the emitter bodies, optical inspection unit 136 may be adapted to inspect a positioning of at least one membrane.

Figure 1C is a schematic, perspective drawing of injection-molding apparatus 100 of Figure IA;

Figure 2A is a schematic, perspective drawing of a cavity set 121 having a plurality of cavity inserts including drip emitter body cavity inserts 123 and their respective drip emitter cover cavity inserts 127.

Figure 2B is a schematic, magnified, partial view of Figure 2A, showing two pairs of cavity inserts in greater detail. Each pair includes one emitter body cavity insert 123 along with an adjacent emitter cover cavity insert 127. Within emitter body cavity insert 123 may be seen a schematic negative form of a drip emitter labyrinth 123A.

Rotating mold 120 may preferably have a cubic or elongated cubic shape. Typically, each of the at least 4 rotating faces is adapted whereby at least one major process step is effected at each of the at least four stop positions. The steps, which may be better understood with reference to Figure 3, are described below in stages or sub- steps. The timing of each of the operations may be controlled by controller 180.

Stage (a) The mold is closed. In this position, injection into Face 1 may be effected to form an emitter base or housing and a lid or cover alongside the housing.

Stage (b) The mold is opened.

Stage (c) The rotating mold is rotated.

Stage (d) The rotating mold is further rotated.

Stage (e) The rotating mold is further rotated until a 90° rotation is achieved, whereby Face 1 faces up.

Stage (f) The mold is closed. Injection into Face 2 may be effected according to stage (a).

Stage (g) Top (typically optical) inspection to determine the quality of part (emitter housing and cover) fillings. The emitter housing and cover, as shown, are ready for inspection.

Stage (h) Insertion of membranes into emitter bodies, followed by top inspection of membrane positioning. The membrane-filled emitter housing is shown, ready to undergo inspection.

Stage (i) Each drip emitter cover alongside the emitter housing may be flipped (typically about 180°) to cover each respective inserted membrane. The flipping may be achieved using a rack and gear system, or by other means known to those skilled in the art. The closed membrane-filled drip emitter is shown.

Stage (j) The mold is opened and rotated.

Stage (k) The rotating mold is further rotated until a 90° rotation is achieved. The lid may be fixedly/permanently attached to the housing, e.g., by pressure against a snap fit or by a welding operation. Face 2 is now facing up, ready for stage (g). Injection into Face 3 may be effected according to stage (a).

Stage (1) Side inspection of cover positioning in emitters of Face 1. The mold may also exert pressure on the cover to urge the cover into a secure position. A sensor such as a pressure sensor detects if the cover is securely in place.

Stage (m) After a rotation of 90° (whereby Face 1 assumes a down position), the formed drip emitters are ejected. With Face 1 in this down position, Face 2 may undergo stages (k) and (1); Face 3 may undergo stages (g), (h) and (i); injection into Face 4 may be effected according to stage (a).

The mold is then rotated another 90°, whereby Face 1 returns to the initial position of Stage (a). The formed drip emitters in Face 2 are ejected. With Face 2 in this down position, Face 3 may undergo stages (k) and (1); Face 4 may undergo stages (g), (h) and (i).

Figure 4A provides a schematic, top perspective view of one embodiment of an injection-molded drip emitter 400, manufactured according to the present invention. The labyrinth portion of the emitter, not shown for the sake of simplicity, may be structured according to various designs known in the art.

Figure 4B provides a cross-sectional view of the drip emitter of Figure 4A. At the top of Figure 4B is shown a snap fit mechanism 402 that enables a substantially fixed and permanent closure of emitter lid or cover 406 with respect to the emitter base or housing 404. This closure preferably fixes membrane 408 securely in place. Figure 5 A provides a schematic, perspective drawing view of the drip emitter of

Figure 4A. Figure 5B provides a partially cut away view of the drip emitter of Figure 5A, in which the both membrane 408 and snap fit mechanism 402 of cover 406 are exposed. Snap fit mechanism 402 may extend along a portion of the perimeter of the cover, or along the perimeter of the cover in its entirety. It will be appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. An injection-molding apparatus for producing drip emitters, the apparatus comprising:

(a) a feed arrangement, including at least a first feed hopper, said arrangement adapted to receive a solid feed material;

(b) an injection arrangement including:

(i) a feed barrel, fluidly communicating with said feed hopper, (ii) at least one heating element, thermally associated with said barrel, and adapted to heat a volume within said barrel, whereby said feed material is transformed into a viscous heated feed material; (iii) an injection nozzle, fluidly communicating with said volume, and (iv) a mechanically-driven delivery mechanism, at least partially disposed within said barrel, and adapted to advance said feed material towards said injection nozzle, and to deliver said heated feed material, at superatmospheric pressure, through said nozzle;

(c) a mold arrangement including: (i) a stationary mold;

(ii) a mechanically-driven rotating mold, having at least two faces, each having at least one drip emitter cavity set having a plurality of cavity insert pairs, each insert pair including:

(A) a drip emitter body cavity insert, and

(B) a drip emitter cover cavity insert; said stationary mold and said rotating mold adapted whereby each of said faces rotates into a stop position opposite said stationary mold;

(d) a clamping assembly including: (i) a moving platen;

(ii) a support plate adapted to support said platen, and

(iii) at least one tie bar, adapted to guide said platen and said plate, said moving platen and said support plate adapted to move along a longitudinal axis of said tie bar;

(e) a robot assembly including: (i) a robot arm, and

(ii) a gripping unit, associated with said arm, adapted to grip a plurality of membrane units, and to effect placement of each of said membrane units within a respective insert of said drip emitter body cavity inserts, and

(f) a controller, said injection arrangement, said mechanically-driven rotating mold, and said robot assembly responsive to said controller, whereby, when a first face of said faces is rotated into said position opposite said stationary mold, said injection arrangement injects said heated feed material through said nozzle, and into said plurality of cavity pairs, via said stationary mold, to produce each at least partially filled drip emitter body cavity insert and each at least partially filled drip emitter cover cavity insert, and whereby, when said first face is further rotated, said gripping unit effects said placement of said membrane units within each said at least partially filled drip emitter body cavity insert.

2. The apparatus of claim 1, wherein said rotating mold has at least 3 of said faces.

3. The apparatus of claim 2, wherein said rotating mold has at least 4 of said faces.

4. The apparatus of claim 3, wherein said rotating mold has a substantially cubic or elongated cubic shape.

5. The apparatus of any one of claims 1 to 3, further comprising a membrane delivery system adapted to provide said membrane units to said gripping unit.

6. The apparatus of any one of claims 1 to 3, wherein said membrane delivery system includes a membrane feed line adapted to provide said membrane units.

7. The apparatus of any one of claims 1 to 3, said clamping assembly further including:

(iii) a driving and locking system adapted to drive said platen and said plate along said tie bar.

8. The apparatus of any one of claims 1 to 3, wherein said rotating mold is a substantially vertically rotating mold.

9. The apparatus of any one of claims 1 to 3, further comprising an optical inspection unit disposed and adapted to capture images of an area within said faces of said rotating mold.

10. The apparatus of claim 9, said controller is adapted to receive, after said gripping unit effects said placement of said membrane units within said filled drip emitter body cavity inserts, data pertaining to said images, from said inspection unit, and to determine, from said data, positions of each of said membrane units.

11. The apparatus of claim 9, wherein said controller is adapted to receive data pertaining to said images, from said inspection unit, and to determine, from said data, positions of each of said membrane units in relation to each said respective one of said at least partially filled body cavity inserts.

12. The apparatus of any one of claims 1 to 3, further comprising a flipping mechanism adapted to flip a drip emitter cover from each said filled cover cavity insert to cover each respective membrane unit of said membrane units.

13. The apparatus of claim 12, further comprising an inspection unit disposed and adapted to ascertain a positioning of each said cover in relation to said respective membrane unit.

14. The apparatus of claim 13, wherein said inspection unit includes a sensor.

15. The apparatus of claim 13, wherein said sensor includes a pressure sensor.

16. The apparatus of any one of claims 1 to 3, wherein said gripping unit is adapted to simultaneously grip said plurality of membrane units, and wherein said placement of each of said membrane units is a substantially simultaneous placement.

17. The apparatus of any one of claims 1 to 3, wherein when one of said faces is disposed in said stop position opposite said stationary mold, said clamping assembly is adapted to urge said moving platen and said support plate along said longitudinal axis to juxtapose said stationary mold and said rotating mold.

18. The apparatus of claim 1, wherein said robot arm includes a rotating or pivoting robot arm.

19. The apparatus of claim 18, wherein said robot arm includes a vertically extending robot arm, associated with, or attached to, said rotating or pivoting arm.

20. The apparatus of claim 18, wherein a vertically extending robot arm is associated with, or attached to, said robot arm, and wherein said gripping unit is associated with, or attached to, said vertically extending robot arm.

21. An injection-molding apparatus for producing drip emitters, the apparatus comprising:

(a) a feed hopper adapted to receive a solid feed material;

(b) an injection arrangement including:

(i) a feed barrel, fluidly communicating with said feed hopper;

(ii) at least one heating element, thermally associated with said barrel, and adapted to heat a volume within said barrel, whereby said feed material is transformed into a viscous heated feed material, and

(iii) an injection nozzle, through which is delivered said heated feed material, at superatmospheric pressure;

(c) a mold arrangement including: (i) a stationary mold, and

(ii) a mechanically-driven rotating mold, having at least two faces, each of said faces adapted to receive said heated feed material to form at least one drip emitter base and a drip emitter cover disposed substantially alongside said base, said stationary mold and said rotating mold adapted whereby each of said faces rotates into a stop position opposite said stationary mold;

(d) a clamping assembly including: (i) a moving platen;

(ii) a support plate adapted to support said platen; (iii) at least one tie bar, adapted to guide said platen and said plate, said moving platen and said support plate adapted to move along a longitudinal axis of said tie bar;

(e) a robot assembly including: (i) a robot arm, and

(ii) a gripping unit, associated with said arm, adapted to grip membrane units, and to effect placement of each of said membrane units within a respective one of said at least one drip emitter base, and

(f) a controller, said robot assembly responsive to said controller, whereby said gripping unit effects said placement of said membrane units within said respective one of said at least one drip emitter base.

22. A method of producing drip emitters by means of injection molding, the method comprising the steps of:

(a) providing the injection-molding apparatus for producing drip emitters, according to claim 1;

(b) rotating said rotating mold to bring a first face of said faces into said position opposite said stationary mold;

(c) injecting said heated feed material through said nozzle and into said plurality of cavity pairs, via said stationary mold, by means of said injection arrangement, to produce at least partially filled drip emitter body cavity inserts and at least partially filled drip emitter cover cavity inserts;

(d) further rotating said rotating mold into a second position, and

(e) effecting said placement of said membrane units within said at least partially filled drip emitter body cavity inserts, by means of said gripping unit.

23. The method of claim 22, wherein, with said rotating mold in said second position, the method further comprises the step of:

(f) performing step (c) on a second face of said faces.

24. The method of claim 22 or claim 23, further comprising the step of: capturing images of an area within said faces of said rotating mold by means of an optical inspection unit, to determine at least one of: quality of drip emitter bodies in said filled body cavity inserts, quality of drip emitter covers in said filled cover cavity inserts, and membrane positioning.

25. The method of claim 22 or claim 23, further comprising the steps of: further rotating said rotating mold into a third position, and flipping each of said covers, on top of said membrane units, thereby covering each drip emitter body within said partially filled body cavity inserts, to produce the drip emitters.

26. The method of claim 22 or claim 23, further comprising the steps of: further rotating said rotating mold into a third position; flipping each of said covers, on top of said membrane units, thereby covering each drip emitter body within said partially filled body cavity inserts, and fixedly attaching each of said covers to said each drip emitter body, to produce the drip emitters.

27. The method of claim 25, further comprising the step of: inspecting, by means of a sensor disposed in said injection-molding apparatus, a positioning of each of said covers.

28. The method of claim 25, further comprising the steps of: further rotating said rotating mold into a fourth position, and ejecting the drip emitters.

29. The method of claim 23, further comprising the steps of: further rotating said rotating mold into a third position; flipping each of said covers, on top of said membrane units, thereby covering each drip emitter body within said partially filled body cavity inserts, to produce the drip emitters, and, in said third position, performing step (e) on said second face.

30. The method of claim 29, further comprising the step of: performing step (c) on a third face of said faces, while said rotating mold remains in said third position.

31. A method of producing a drip emitter by means of injection molding, substantially as described herein, the method comprising any feature described, either individually or in combination with any feature, in any configuration.

32. An apparatus for producing a drip emitter by means of injection molding, substantially as described herein, the apparatus comprising any feature described, either individually or in combination with any feature, in any configuration.