JPH07334B2 - Method and apparatus for manufacturing plastic screw feeder - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a screw feeder by a plastic extrusion method, and an apparatus for the same. This screw feeder is used for transferring powder, granules, a mixture of liquid and solid, and liquid.

<Prior Art> As a conventional means for transferring powder and granules, a hopper for supplying powder and granules and an intermittent injecting device for compressed air are provided at one end of a transfer tube,
An air conveyor device is known in which powder particles and compressed air lumps are alternately formed in the transfer tube to move them, and at the other end of the transfer tube, a powder particle and air separation device is provided. There is.

However, according to this air conveyor device, not only is the device complicated because it requires an intermittent injection device for compressed air and a separating device at the end, but the transfer efficiency is extremely high because compressed air must be mixed. It has the drawback of being low.

Further, as a method for manufacturing a plastic screw feeder, as disclosed in JP-A-61-66625,
Hollow rod-shaped synthetic resin material, a method of blow molding in a mold having a thread on the inner peripheral surface, or, as disclosed in JP-A-55-4401, an injection molded article of finite length, A method is known in which connection is sequentially made by a flange joint. However, the present inventor has not yet found a manufacturing technique for continuously molding a long plastic screw feeder.

<Problems to be Solved by the Invention> On the other hand, the object of the present invention is not limited to powder and granular material, it is possible to transfer a mixture of liquid and solid such as slurry, the liquid itself with high efficiency. It is an object of the present invention to provide a method of manufacturing a screw feeder, which can be manufactured, is very simple, and can be manufactured at a very low cost, and a device therefor.

One of the problems in achieving this object has been how to efficiently and inexpensively manufacture the rotor portion of the screw feeder.

Another important issue is how to provide an apparatus for implementing this manufacturing method to obtain a high quality product with a simple structure and at a low cost.

<Means for Solving the Problems> The manufacturing method of the present invention includes an extruder for extruding a plastic material, a nozzle having a predetermined diameter provided at the material discharge port at the tip of the extruder, and a center of the nozzle. And a core material feeding means for feeding the core material, and is coaxial with the nozzle outside the nozzle, and has a tapered shape whose outer diameter increases in a direction away from the nozzle, and has an axial length of a spiral groove. A plurality of rolling rollers having a pitch or more are provided, and each rolling roller is extruded from the extruder using a molding device having a rolling die device that revolves around the core material while rotating in synchronization with each other. After the plastic material adhered to the core material is sent out by the core material feeding means through the nozzle, the spiral die is formed on the outer periphery of the plastic material by the rolling die device. Characterized.

The manufacturing apparatus of the present invention is an extruder for extruding a plastic material, a material reservoir provided at the tip of the extruder, and a core material of a screw feeder to be manufactured while introducing the material into the reservoir while supporting the core material. A core material inlet provided on the wall surface of the reservoir, a core continuous feeding means provided outside the core inlet, and a diameter larger than the diameter of the core provided at the core outlet of the reservoir. It has a nozzle and a rolling die device provided outside the nozzle, and the rolling die device is
A rotary housing having openings in both the front and rear walls through which the core material and the plastic material pass, and rotating around the same axis as the nozzle, and is housed in the housing by being axially supported by the front and rear walls of the rotary housing. A synchronous rotation device is provided in which a plurality of rolling rollers having spiral grooves engraved on the outer periphery thereof, a large gear provided on the rotary housing, and a small gear provided on each of the plurality of rolling rollers mesh with each other. It is characterized by having.

<Embodiment> FIG. 1 shows a sectional view of an embodiment of a manufacturing apparatus used for carrying out the present invention.

The extruder has an extruding rotor 2 for extruding a material in the center of a cylindrical container 1, a material reservoir chamber 3 is provided at the tip of the extruding rotor 2, and two through holes 4 are provided coaxially in a direction orthogonal to the extruding rotor 2. , 5 are formed. One of the through holes 4 and 5 is the core material inlet 4, and the other is provided with a nozzle 6 having a diameter larger than the diameter of the core material. The core material introduction port 4 constitutes a bearing to support the core material 7, and a core material continuous feeding means 8 such as a pinch roller is provided outside the introduction port 4, and the core material 7 is fed at a constant speed v. To be

Outside the nozzle 6, a rolling die device 9 is rotatably supported concentrically with the core 7. This rolling die device 9
Is, for example, three rolling rollers 11A,
11B and 11C are rotatably supported by bearings provided in the housing 10, and the rolling rollers are configured to rotate by a gear mechanism 12 in synchronization with each other.
A, 11B and 11C have a tapered outer shape, and spiral rolling grooves having different phases are engraved for more than 3 pitches. The root diameters of the rolled grooves are the same and the pitch p is also the same.
The rotary housing 10 is provided with a large gear 13, and a small gear 14 meshing with the large gear 13 is driven by a motor 15 to revolve the rotary housing 10.

The running speed of the core material 7 is v (cm / sec) and the pitch of the rolling groove is p
(Cm) and the rotational speed of the rotary housing 10 is n (rpm), the following relational expression holds.

The core material 7 is made of metal or plastic.
When plastic is used, a material having a melting point higher than that of the plastic material to be extruded is selected. The cross-sectional shape of the core material 7 is, as shown in FIG. 3, (a) a hollow cylindrical shape, (b) an inner surface with axial grooves, (c).
It can be implemented by a solid column, (d) coaxial multi-layer structure, or the like.

In the method of manufacturing a screw feeder using this apparatus, the plastic material extruded by the extruder adheres to the core material 7 and is fed from the nozzle 6 by the core material continuous feeding means 8 and then enters the rolling die device 9. , Rolling rollers 11A, 11
Compressive plastic working is performed by B and 11C, and the spiral portion 17 is roll-formed. It should be noted that the mountain shape of the spiral portion 17 can be implemented in various shapes depending on the application.

In the above-mentioned embodiment, the axial direction of the core material 7 has been described, but it can also be carried out by oblique descending, vertical descending, etc., and can also be cooled by air cooling or water cooling after rolling.

The product of the present invention is inserted into a tube and is used as a screw rotor by rotationally driving one end of a core material. When the structure shown in FIG. 3 (b) is used as the core material, a drive shaft engaging with the groove can be inserted to increase the torque.

<Effect of the Invention> According to the present invention, since the spiral portion is formed by the rolling method, the continuous screw rotor can be efficiently manufactured at low cost.

In addition, a plurality of rolling rollers having a taper outer diameter and a spiral groove with an axial length of 2 pitches or more are provided, and these rolling rollers revolve around the core while rotating in synchronization with each other. Since a rolling die device is used, the shape of the spiral ridge formed is accurate even if the ridge is raised, there is no residual strain in the spiral part, and a screw feeder with a large pitch density is manufactured. be able to.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a manufacturing apparatus used for carrying out the present invention, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a transverse view showing each embodiment of a core material 7 of the present invention. It is a side view. 1 ... Extruder container 2 ... Extrusion rotor 3 ... Material storage chamber 4 ... Core material inlet 6 ... Nozzle 7 ... Core material 8 ... Core material continuous feeding means 9 ... Rolling die device 10 ... … Rotating housing 11A, 11B, 11C …… Rolling roller 15 …… Motor

Claims (2)

[Claims] 1. An extruder for extruding a plastic material, a nozzle having a predetermined diameter provided at a material discharge port at the tip of the extruder, and a core material feeding means for feeding a core material through the center of the nozzle. A plurality of rolling rollers are provided outside the nozzle, the outer diameter of which is increased in a direction away from the nozzle, and the axial length thereof is two pitches or more of spiral grooves. Using a molding device having a rolling die device that revolves around the core material while the rollers rotate in synchronization with each other, the plastic material extruded from the extruder adheres to the core material and passes through the nozzle. A method for manufacturing a plastic screw feeder, characterized in that, after being fed by the core material feeding means, a spiral mountain is formed on the outer periphery of the plastic material by the rolling die device. 2. An extruder for extruding a plastic material, a material reservoir provided at the tip of the extruder, and a reservoir for introducing the core material of a screw feeder to be produced into the reservoir while supporting it. A core material inlet provided on the wall surface,
A core material continuous feeding means provided outside the core material introduction port, a nozzle provided at the core material outlet port of the reservoir and having a diameter larger than the diameter of the core material, and provided outside the nozzle. And a rotary housing which has an opening through which the plastic material passes through the core material on both front and rear walls, and which rotates around the same axis as the nozzle, and A plurality of rolling rollers which are axially supported by both front and rear walls of the rotary housing and are housed in the housing and spiral grooves are engraved on the outer periphery thereof, a large gear provided on the rotary housing and the plurality of rolling rollers. An apparatus for manufacturing a plastic screw feeder, which has a synchronous rotation device in which the small gears provided in each of the two mesh with each other.