JPH0216068Y2 - - Google Patents

Description

[Detailed description of the invention] The invention consists of an eccentric screw pump having a rotor and a stator, and a screw feeder installed adjacent to the upstream side of the eccentric screw pump. a casing having a material inlet at the casing, and a screw shaft connected within the casing at one end to one end of the rotor of the eccentric screw pump and at the other end to a drive means;
This invention relates to a conveying device for materials with poor fluidity and low specific gravity.

A conventional device of this type is shown in FIG. Reference numeral 10 denotes a well-known uniaxial eccentric screw pump, which includes a stator 12 made of an elastic body such as rubber and consisting of a female screw having an oval cross section;
A rotor 14 consisting of a male thread that reciprocates in a direction perpendicular to the axis while rotating within the stator 12
and a metal outer cylinder 16 into which the stator 12 is fitted.
It consists of. The discharge side of the eccentric screw pump 10 is supported by a support base 18 having a discharge hole, and the inlet side of the eccentric screw pump 10 is connected to the discharge side of the casing 22 of the screw feeder 20. The opposite side of the casing 22 is connected to the end of a bearing pedestal 26 with a seal 24. One end of the screw shaft 28 of the screw feeder 20 is connected to one end of the rotor 14 of the uniaxial eccentric screw pump 10 via a universal joint 30, and
The other end of the transmission shaft 34 is connected via a universal joint 30' to one end of a transmission shaft 34 rotatably supported on the bearing stand 26 by bearings 32, 32'. The upper part of the casing 22 has a hopper-shaped rectangular material input port 36.

To explain the operation of such a conventional conveying device, immediately after starting the eccentric screw pump, the casing 2
The material with poor fluidity introduced from the second material input port 36 is fed to the inlet of the uniaxial eccentric screw pump 10 by the screw 29 of the screw shaft 28 that rotates via the transmission shaft 34. The material is then sucked into a rotor-stator chamber between rotor 14 and stator 12 by negative pressure generated by rotor 14, which reciprocates up and down while rotating within stator 12. In the rotor-stator chamber, the sealed space formed between the rotor 14 and the stator 12 moves continuously toward the outlet side due to the rotation of the rotor 14, thereby sending the material to the outlet, from where it is transported to a desired location by a conduit. Ru.

However, the material input port 36 of the casing 22 of the screw feeder 20 occupies most of the length of the screw shaft, and the portion of the guide wall along the screw 29 of the screw shaft 28 that rotates eccentrically is extremely short. Ta. Even with this type of screw feeder, relatively heavy materials such as dehydrated cakes can be conveyed without problems because they come into close contact with the screw due to gravity, but relatively light materials with a specific gravity of around 0.5 and poor fluidity such as synthetic resins, for example, can be transported without problems. In this case, if the axial length of the casing guide wall on the delivery side is very short as described above, the conveying force will be weak, and the material will flow in the area of the screw shaft 28 below the input port 36 where there is no guide wall. It floats upwards due to the rotating screw,
The drawback was that the transport efficiency was extremely low.

An object of the present invention is to eliminate the above-mentioned drawbacks and provide a conveying device for materials with poor fluidity, which can efficiently convey even materials with relatively light specific gravity.

In order to achieve the above object, the present invention provides at least two pitches of screws of the screws fixed to the screw shaft, on the guide wall of the casing along the eccentrically rotating screw shaft, on the screw feeder. It may be disposed between the delivery end and the lower edge on the downstream side of the material input port.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows an embodiment of a conveying device for a material having a relatively light specific gravity and poor fluidity according to the present invention. 1st
Similar parts to those in the figures have been given similar reference numerals.

According to the present invention, the guide wall of the casing 122 along the eccentrically rotating screw shaft 128 of the screw feeder 120 extends from the feed end 128a of the screw feeder to the lower edge 136a of the material input port 136 on the downstream side of the screw shaft. Screw 129
having an axial length extending over at least two pitches of. In this example, casing 122
The delivery side guide wall has a length of six pitches of the screw 129.

In the present invention, as mentioned above, the guide wall on the delivery side along the eccentrically rotating screw shaft 128 is made longer than in the prior art to increase the conveying force. Even poor material can be efficiently fed to the single-shaft eccentric pump by the screw shaft 128 without floating within the range of the material input port. It is also advantageous that a kneading effect of the material also occurs while the conveyed material is conveyed through the area of the long delivery-side guide wall of the casing of the screw feeder.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of a conventional conveying device for materials with poor fluidity, and FIG. 2 is a vertical sectional view of the device according to the present invention. 110... Eccentric screw pump, 112... Stator, 114... Rotor, 120... Screw feeder, 122... Casing, 128... Screw shaft, 129... Screw, 136... Material input port, 128a... ...The sending end of the screw feeder, 136a...The lower edge on the downstream side of the material input port.

Claims (1)

[Scope of utility model registration request] an eccentric screw pump having a rotor and a stator;
A screw feeder is provided adjacent to the upstream side of the eccentric screw pump. In a conveying device for a material with poor fluidity and low specific gravity, which has a screw shaft connected to one end and a drive means at the other end, at least two pitches of the screws fixed to the screw shaft are A conveying device characterized in that a screw is disposed between a guide wall of a casing along an eccentrically rotating screw axis and from the delivery end of the screw feeder to the lower edge on the downstream side of the material input port.