JPH01123703A - Raw material feeding device of powder molder - Google Patents

Abstract

PURPOSE:To contrive to homogenize product and to reduce errors in weight by a structure wherein a plurality of variable speed agitating blades, the rotating shaft of which is perpendicular to a charger table, and at the same time a weighing means, which feeds a certain weight of raw material to a charger box at the predetermined position, are provided. CONSTITUTION:A charger box 7 moves back and forth on a charger table 2, which abuts against the horizontal top surface of a mold 21. In addition, a metering hopper 17 and a feeder 20 are provided. On a plate 8 in the box 7, a plurality of variable speed blenders 10, the rotating shafts 9 of which are perpendicular to the table 2, are provided through arms 11. The blenders 10 have circular arc-shaped horizontal sections, which are concave in the wake side in the direction of rotation, and their rotational phases are shifted so as to intersect their rotational planes at their sides opposing to each other. At the operation of the device concerned, raw material A, which is carried with the feeder 20, is correctly metered in weight with load cells 18 at the metering hopper 17 and fed to the box 7 so as to be agitated with the blenders 10 and pushed in a cavity 22, resulting in homogenizing product and making errors in weight smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a raw material supply device for feeding a fixed amount of raw material into a mold of a powder molding machine.

[Prior art] For example, in the molding of refractory bricks, a quantitative raw material supply device that inputs a certain amount of raw material automatically feeds the raw material uniformly and automatically into a mold without segregation, that is, separation of coarse particles and fine particles. It is widely used as a simple device that can be supplied. However, there is a problem in that the weight of the raw material supplied into the mold by this device varies considerably depending on the type of blended raw materials, binder, etc.

On the other hand, a device equipped with stirring blades, so-called blenders 10a, as shown in FIGS. 9 to 11 is known. That is, two blenders 10a, 10a whose rotary shafts 9a rotate in parallel and opposite directions to the charger table 2 are installed inside a charger box 7a that reciprocates on the charger table 2 by the air cylinder 5.
is installed to receive a fixed amount of raw material A from the raw material hopper 24 (
9), the blenders 10a, 10a are conveyed onto the cavity 22 of the mold 21, and the lower punch 23 is lowered.
10 to feed the raw material A into the cavity 22 by rotating the
(Fig. 11), it retreats back to the raw material hopper 24 and receives the raw material A (Fig. 11). However, in this device, it is difficult to mix raw materials with a large difference in specific gravity, such as graphite and magnesia. In this case, air is trapped by the rotation of the blenders 10a, 10a, making the bulk density unstable and increasing the weight error. Furthermore, charger box 7
At the time of retreat of a, the raw material remaining in the charger box 7a pressurizes the rear part B of the mold cavity 22, increasing the density and biasing the variation in weight. Figure 12 shows the measurement results of the product weight when molding bricks with a weight of 15%, and shows that there is a large variation of +/-200M against the target value of +/-100g.

In addition, the raw material is accurately weighed by a weighing hopper 17 equipped with a load cell 18 (not shown in FIG. 1), which is a weighing means of the present invention.
A so-called gravimetric weighing type device is known in which material is charged into a mold cavity via a charging hopper (not shown). However, since the material is charged from a fixed height, there are problems such as the material not entering the mold cavity 22 uniformly, the need for segregation of the raw material, and the need for hand conditioning.

[Object of the Invention] Accordingly, an object of the present invention is to provide a raw material supply device for a powder molding machine that can produce a homogeneous product with little weight error.

[Structure of the Invention] According to the present invention, in a raw material supply device that feeds a fixed amount of raw material into a mold of a powder molding machine, a rotating shaft is provided inside a charger box that reciprocates on a charger table and is perpendicular to the charger table. A plurality of variable speed stirring blades are provided, and a weighing means is provided at a predetermined position to supply a constant weight of raw material to the charger box.

[Operations and Effects of the Invention] Therefore, a constant weight of the raw material supplied from the weighing means is suitably stirred by the stirring blade in the charger box,
In addition, since the material is pushed into the mold from multiple directions, the quality of the product can be made uniform and weight errors can be reduced. In addition, if there are ball-like lumps in the raw material, they can be crushed to a considerable extent and the unrestrained weight I error due to the ball-like lumps can be reduced.

[Preferred Embodiment] When carrying out the present invention, it is preferable to use, for example, a known air cylinder for reciprocating the charger box.

When carrying out the present invention, it is preferable that the stirring blade is formed in an arc shape with a concave downstream side in the rotational direction, and further formed so that the lower end is bent toward the downstream side in the rotational direction.This will improve the stirring effect. The pushing effect can be improved.

In carrying out the present invention, it is preferable to use a known variable speed motor such as an air motor, hydraulic motor, or inverter motor to rotationally drive the stirring blades.

When carrying out the present invention, the weighing means is equipped with a load cell,
Preferably, a known weighing hopper with double doors at the bottom is used.

When implementing the present invention, the weight supplied to the charger box by the weighing hopper is determined by adding the weight that will become the head at the time of injection into the mold to the product weight, and is determined by experiment to be optimal depending on the raw material within a range of 1.5 to 3 times. Preferably, a value is selected.

In practicing the invention, it is preferred to include a conventional level sensor for checking the level of raw material supplied to the charger box.

〔Example] The present invention will be described in detail below with reference to the drawings.

In FIG. 1, the raw material supply device, which is designated as a whole by reference numeral 1, is
A charger table 2 provided in contact with the horizontal upper surface of a mold 21, a charger box 7 driven by a known air cylinder 5 to move back and forth on the charger table 2, and a weighing hopper 17 serving as a weighing means. and,
It consists of a feeder 2°.

In Figures 2 to 4, the charger table (
(hereinafter referred to as table) 2 has a cavity 22 of the mold 21.
A rectangular elongated hole 3 is formed to face directly, and guide rails 4.4 are erected in the left-right direction.

The charger box (hereinafter referred to as the box) 7 has a horizontal cross section that largely surrounds the long hole 3 and is shaped like a cocoon to be guided by the guide rail 4.4, with the upper part opening outward like a hopper, and the lower part being shaped like a hopper. The rear side is connected to the piston rod 6 of the air cylinder 5. A base plate 8 is horizontally stretched slightly downward from the center of the box 7 with a gap left and right, and a plurality of (two in the illustrated example) blenders are mounted on the plate 8, with a rotating shaft 9 perpendicular to the table 2. 10.10 is provided via an arm 11.11. The horizontal section of this blender 10 is formed into an arc shape with a concave downstream side in the direction of rotation, and the outer edge of the blender 10 is shaped like a box 7.
It slides against the cocoon-shaped inner wall and rotates in opposite directions as shown by the arrows, and its lower edge is bent toward the downstream side in the direction of rotation. Opposing sides of the blender 10.10 are therefore out of phase so that the planes of rotation intersect.

A gear box 12 to which a rotating shaft 9.9 is connected is provided on the base plate 8, and the gear box 12
An output shaft of a variable speed motor 14, such as a known air motor, hydraulic motor, or inverter motor, is connected to a bracket 13 projecting from the rear of the box 7. Further, the plate 8 is provided with a known level switch 15 for detecting the level of the raw material in the box 7.

The base plate 8 and everything provided thereon are covered with covers 16 that rise from both side edges of the base plate 8 and close at the upper edge of the box 7 in a triangular shape.

In FIG. 1, the weighing hopper 17 has a load cell 18.
．． 18, and the lower opening is provided with a door 19, 19 that opens back and forth as shown by the chain line. A known belt conveyor is used as the feeder 20. The apparatus 1 is capable of simultaneously supplying raw materials to two molded products each having a rectangular plane as shown by the dashed line in FIG. 4, or to a square product 3111 as shown by the dashed line.

During operation, the raw material A conveyed by the feeder 20 is accurately weighed by the load cell 18. (Fig. 1).At this time, add the weight of the head at the time of feeding to the weight of the molded product, and select the optimum value by experiment according to the raw material and weigh it in the range of 1.5 to 3 times. The level switch 15 is used to check whether the supply amount is too much or too little.

Next, while rotating the blender 10.10 at a low speed, the air cylinder 5 is extended to move the box 7 forward until it directly faces the elongated hole 3 of the table 2, and then stops (FIG. 5).

Next, the lower punch 23 is lowered and the raw material is transferred to the blender 1.
The raw material is poured into the cavity 22 while being stirred at 0.0.

As a result, as shown in FIG. 8, the variation in weight is small and is so small as to fall comfortably within the target value plus or minus 100".

Next, the air cylinder 5 is contracted to move the box 7 directly below the weighing hopper 17, and the raw material is supplied again (FIG. 7), and the mold 21 is moved one pitch in the direction perpendicular to the plane of the paper. At this time, the raw materials remaining in box 7 are transferred to blender 10.10.
Since only the rear portion B of the cavity 22 is not pressed, the density of only that portion B is prevented from increasing and the weight is prevented from varying.

[Summary] As explained above, according to the present invention, the raw materials are stirred by a plurality of blenders rotating around a vertical axis of rotation, and are pressed into the mold cavity, thereby homogenizing the product and reducing the weight. Errors can be reduced, and the powder compacting machine can be operated unmanned and at high speed.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing one embodiment of the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, Fig. 3 is a sectional view taken along the line X--X of Fig. 2, and Fig. 4 is a sectional view taken along the Y-Y line in Fig. 2, Fig. 5,
6 and 7 are side sectional views showing the process, FIG. 8 is a diagram showing a product weight measuring device to explain the effects of the present invention, and FIGS. 9, 10, and 11 are conventional views, respectively. FIG. 12, a side sectional view showing the steps of the apparatus, is a drawing corresponding to FIG. 8 of the conventional apparatus. A... Raw material 1... Raw material supply device 2... Charger table 5... Air cylinder 7.
...Charger Bo Six 9...Rotation axis 1
0...Blender 14...Variable speed motor -
7...Weighing hopper 18...Load cell 20.
...Feeder 21...Mold 22...Cavity 1st gJ FuO Fig. 5 and 2117 Fig. 3 Fig. 6 Agony Lf, -17 Fig. 7

Claims (1)

[Claims] In a raw material supply device that feeds a fixed amount of raw material into a mold of a powder molding machine, a charger box that reciprocates on a charger table is provided with a plurality of variable speed stirring blades whose rotating shafts are perpendicular to the charger table, and A raw material supply device for a powder molding machine, characterized in that a weighing means for supplying a constant weight of raw material to a charger box at a predetermined position is provided.