JP3513725B2 - Cylindrical screen classifier - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic fiber woven mesh cylindrical screen which is attached in a direction of a center line, and a rotating shaft which rotates at a high speed on the center line. The present invention relates to a cylindrical screen classifier in which powdery raw material supplied from one end of a cylindrical screen is sieved by several rotating blades mounted radially and at a slight twist angle with respect to a center line. . 2. Description of the Related Art A cylindrical screen classifier has a size of 42 microns.
When a cylindrical screen made of synthetic fiber woven mesh of 50 micron, 72 micron, or 150 micron is installed and toner, powder coating, etc. are to be sieved, these materials strongly generate static electricity when stirred by the rotating blades. It takes on and adheres to the inner surface of the cylindrical screen, and the sieving operation is not performed. For this reason, as described in Japanese Patent Application Publication No. 4-76749, several or tens of elastic balls made of synthetic resin, rubber or the like are loaded into a cylindrical screen, and the rotating screen rotates at a high speed. It hits the inner surface of the cylindrical screen by striking it with wings, causing dramatic vibrations in each part of the cylindrical screen to prevent clogging. Further, as shown in FIG. 3, the conventional cylindrical screen classifier has a cylindrical screen 109 having both ends connected to the outer surfaces of the cylindrical portions of the cylindrical screen fittings 110 and 111, and a cylindrical screen 109 having a cylindrical screen. A belt-like rotating blade 117a radially attached to the rotating shaft 114 rotating at a high speed on the center line and at a slight twist angle with respect to the center line;
117b... The elastic balls 121a, 121b,... Put in the internal space of the cylindrical screen 109 are beaten by the rotating wings, fly at high speed, collide with the inner surface of the cylindrical screen 109, generate vibrations, and generate vibration. Prevents clogging of the inner surface. However, the elastic ball that comes to the vicinity of the end face of the cylindrical portion of the cylindrical screen mounting member 111 on the coarse powder discharging side has a twist angle to move the raw material toward the coarse particle discharging side in the direction of arrow A117. Rotating wings 117a, 117
.., and rolls on the inner surface of the cylindrical screen 109 at high speed along the end surface of the cylindrical screen mounting bracket 111 having a radial height of 2.5 mm to 4 mm. Due to the movement of the elastic ball, the cylindrical screen 109 is broken from the end on the discharge side. [0007] The wires of the screen having a very small mesh as described above must be made of polyester or nylon having a diameter of 72 to 120 microns, and thus are easily broken. This breakage occurs mainly in the portion near the cylindrical screen at the coarse powder discharge side end. [0008] This cylindrical screen is very expensive because it uses a thin strand of wire for the warp and weft to make an extremely small and accurate opening fabric and makes a cylindrical one with reinforced joints and both ends. It will be. Therefore, increasing the life is an issue to be solved. [0009] The present invention SUMMARY OF THE INVENTION are in surface to the end surface of the cylindrical portion of the cylindrical screen mounting bracket coarse powder discharge side end of the rotor blades to obtain beating elastic ball is on synthetic fibers think Department
The object is to solve the above-mentioned problem by bending the rotor 10 to 30 degrees in the rotation direction. According to the present invention, the end of the impeller on the coarse powder discharge side is bent by 10 to 30 degrees in the direction of rotation of the impeller, so that the elastic ball hit at this point is a cylindrical screen. Will be returned toward the interior space of the. Therefore, the cylindrical portion of the cylindrical screen mounting bracket must be 2.5 to maintain rigidity.
Although there is a thickness of 4 to 4 mm, it does not roll on the inner surface of the cylindrical screen at high speed along the end surface of the cylindrical screen mounting bracket on the coarse particle discharge side, and therefore, the phenomenon that the discharge side end of the cylindrical screen is damaged Is prevented. An embodiment of the present invention will be described with reference to the accompanying drawings.
A door 2 is provided on one end face of the casing 1, and a raw material supply pipe 4 and a bearing box 5 are provided on the other end face 3. The interior of the casing 1 is divided into two rooms by a vertical wall 6, and the bottom of each room has a fine powder outlet 7, a coarse powder outlet 8
It has become. Both ends of the synthetic fiber woven mesh cylindrical screen 9 are adhered to the outer surface 11c of the cylindrical portion 11 of the inlet-side mounting bracket 10 and the discharge-side mounting bracket 11, respectively. Mounting bracket 11
Is attached to the vertical wall 6, and the mounting bracket 10 is fitted in a ring 12 provided on the end face 3. The bolt 13 is connected to the cylindrical screen 9 by the center line 9.
We are nervous in the direction of a. The rotating shaft 14 is supported by the bearing housing 5, and is rotated in the direction of arrow A16 by a belt (not shown) wrapped around the pulley 15 at the end. The belt-like rotating blades 17a, 17b...
8a, 18b... And arms 19a, 19b... So that there is a slight twist angle α with respect to the center line of the rotating shaft 14. As the twist angle α, for example, 2.
Five degrees are chosen. The ends 20a, 20b,... Of the rotating blades 17a, 17b,... On the coarse powder discharge side are bent by an angle β in the rotation direction. As the angle β, for example, 15 to 30
The degree is chosen. In the internal space of the cylindrical screen 9, elastic balls 21a, 21b,... Having a diameter of 4 to 12 mm are inserted. The blocking disc 22 is mounted at right angles to the rotating shaft 14, and the gap between the outer diameter of the blocking disc 22 and the inner diameter of the cylindrical screen mounting bracket 11 is smaller than the diameter of the elastic balls 21a, 21b. The sieved raw material 23 enters the inside of the cylindrical screen 9 through the raw material supply pipe 4, and is rotated by rotary blades 17a, 17b.
While being swirled along the inner surface of the cylindrical screen 9 and sent to the coarse powder discharge side by the action of the twist angle α of the rotary blades 17a and 17b. The elastic balls 21a, 21b...
are struck by a, 17b,... and collide with the inner surface of the cylindrical screen 9 to generate severe vibration, thereby preventing the raw material 23 from adhering to the inner surface of the cylindrical screen 9. Particles 23a smaller than the mesh of the cylindrical screen 9 in the raw material 23 are:
Through which is discharged from the fines outlet 7 to the outside, the coarse powder outlet through between the outer diameter of the inner diameter and cut-off disc 22 of large coarse 23b from mesh of a net discharge side circular cylindrical screen mounting bracket 11 From 8 is discharged outside the machine. By bouncing around the inner surface of the cylindrical screen 9,
It happens cylindrical portion 1 of the discharge-side circular cylindrical screen mounting bracket 11
The elastic ball 21c coming to the end face 11b of the rotor 1a
b is hit by the bent end portion 20 b and returned to the inside of the cylindrical screen 9. The present invention is configured as described above.
In the elastic ball charged inside the cylindrical screen, the inner surface of the cylindrical screen is rolled while being accelerated by the rotary wing along the end face facing the inside of the cylindrical screen of the cylindrical part of the mounting bracket on the coarse powder discharge side. The phenomenon of turning can be prevented. For example, a cylindrical screen classifier having a cylindrical screen having an inner diameter of 250 mm, an effective length of 200 mm, a number of rotary blades of 4, a rotational speed of a rotary shaft of 500 rpm, a diameter of 6.35 mm, and eight elastic balls made of urethane rubber. When a woven mesh of carbon-containing polyester having a thickness of 102 microns and a mesh size of 50 microns is attached and a toner having an average particle size of 8 microns is sieved at 200 kg / h, the average life of the woven mesh is conventionally 8 hours a day. This was about one week, but according to the present invention, it could be about three weeks. However, the twist angle α of the rotor blade was 2.5 degrees, and the bending angle β at the end on the discharge side was 15 degrees.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of an embodiment of the present invention. FIG. 2 is a sectional view taken along the line II-II in FIG. FIG. 3 is a vertical sectional view of a portion of the prior art. DESCRIPTION OF SYMBOLS 1 Casing 4 Raw material supply pipe 5 Bearing box 9 Cylindrical screen 10 Inlet side mounting bracket 11 Outlet side cylindrical screen mounting bracket 11a Cylindrical part 11b End face 11c Outer face 14 Rotation shafts 17a, 17b Rotor blade 17e Outer edge 20a, 20b , 20c, 20d bending end portions 21a, 21b , 21c, 21d elastic ball 22 blocking disc α twist angle β bending angle

Claims (1)

(57) [Claims 1] A cylindrical screen made of a synthetic fiber woven net having both ends respectively connected to the outer surface of the cylindrical portion of the mounting bracket, and being attached with tension in the direction of the center line. A rotating blade which is radially attached to the rotating shaft rotating at a high speed on the center line and at a slight twist angle with respect to the center line, so that there is a small gap between the outer edge thereof and the inner surface of the cylindrical screen; Several elastic balls made of synthetic resin or rubber having a diameter of 4 to 12 mm, which are inserted into the inner space of the cylindrical screen;
A cylindrical screen mounting bracket at the coarse particle discharge side end where the coarse particles larger than the mesh of the cylindrical screen in the powdery raw material supplied inside from one end of the cylindrical screen are mounted at right angles to the rotating shaft. A cylindrical screen classifier having a blocking disc having a diameter smaller than the diameter of the elastic ball between itself and the inner surface of the cylindrical portion of the cylindrical screen. and the surface on the end surface of the cylindrical portion, and an end portion of the rotary blade to obtain beating elastic ball is on synthetic fibers think is, 10 in the rotational direction of the rotor blade
A cylindrical screen classifier characterized by being bent from 30 to 30 degrees.