JPH07204583A - Powder remover - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a compact device for separating powder from a crushed product of a plastic runner. [Structure] A slanted double net is provided, the upper net is reciprocated, and the lower net is fixed. Even if a pointed crushed piece hits the upper net mesh, it falls out. . Therefore, it is hard to be clogged. There is no need to stop running and clean the net frequently. Since it can be a small device,
It can be placed at the crushed product outlet of the crusher. It is possible to save labor, unlike placing a container for receiving the runner-crushed product in the crusher and carrying the crushed product to the vibrating screen when the crushed product is stored. It is effective in promoting labor saving.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust remover for selecting and removing powder when a runner generated in a plastic molding machine is crushed and used as a regenerated raw material as a crushed piece (pellet). A mold is used in a plastic molding machine, and the mold has a cavity corresponding to the molded product and a connecting portion connecting the cavity and the plastic inlet. The runner is the plastic that hardens at the connection. The runner is separated from the product. Since several products are molded at once, there are rod-shaped and frame-shaped products with many branches. This is crushed with a crusher and reused as a raw material. Since it is mechanically crushed by a crusher, the size of the fragments varies. This is mixed with the raw material of virgin and put into the feeder of the molding machine.

However, powder is generated during pulverization. When powder and pellets (crushed pieces) are mixed, the powder does not melt well even when placed in a feeder and heated, so that a molten raw material of uniform quality cannot be obtained. This is a problem. As long as the crusher crushes the runner with the rotary blade and the fixed blade, the generation of powder is unavoidable. The crushed product always contains powder. Even if the structure of the crusher is devised, the generation of powder cannot be prevented. Therefore, it is absolutely necessary to remove the powder from the crushed pieces.

[0003]

2. Description of the Related Art A device for removing powder is essentially a sieving device, and a crushed material is supplied to a net or a perforated plate so that the crushed material slides down to separate the powder and crushed pieces (pellets). Several devices have been devised and utilized in this regard. This will be described.

[Prior Art Example 1 Cylindrical Sieve Device] A stainless steel cylindrical net is slanted and rotated around an axis. Insert the crushed product from the upper opening. The powder falls from the net. The debris falls through the lower opening. In such a case, since the net is clogged, a mechanism for preventing clogging by a hammer is provided. Install the hammer in the rotating cylinder. Hammer
The proximal side of the is pivoted by a pin, and the mallet has a free end. The tilt angle of the hammer changes as the cylinder rotates. Sometimes the hammer lifts and hits the net. This can prevent clogging.

[Prior Art Example 2 Planar Tilt Sieve Device] Punching metal or stainless mesh is fixed to a flat plate frame, and the frame is supported obliquely for reciprocating motion. Drop the crushed material on the net. The powder falls through the net. Since the debris does not pass through the net, it falls down.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
There is already a track record. However, these are all large-sized devices, and cannot be directly attached below the discharge port of the crusher. The outlet of the crusher is at the bottom of the casing. The distance to the ground is only a few tens of centimeters. It is not possible to put a large device under the spout.

In particular, the cylindrical sieving apparatus cannot be downsized because the length and height are considerably large. Since the flat inclined type is easily clogged, it is necessary to increase the area of the net in order to reduce the number of cleanings. Therefore, it cannot be miniaturized. That puts the dust remover in a different location than the crusher. A container is placed at the discharge port of the crusher, and when the crushed material is stored in this, the container is taken out and the sieve device (powder)
Need to throw in. This requires human intervention and ultimately results in high costs. The flat inclined sieve is liable to be clogged with debris on the net. When it becomes clogged, it reverses the net and beats it to drop the debris. Clogging frequently occurs. The net should also be cleaned frequently. Since this also requires human operation, the cost is high. There is also the problem of the net. Conventional ones use punched metal or stainless steel mesh. It resists friction and prolongs life. However, metal nets tend to be clogged with crushed material. This is a property discovered by the present inventor. Since the thread of the net does not move in the metal net, once the debris is clogged, it cannot be easily removed.

The present invention is directed to overcoming the disadvantages of these conventional dusters. It is a first object of the present invention to provide a compact dust remover that can be connected to the outlet of a crusher. It is a second object of the present invention to provide a dust remover capable of preventing the net from being clogged with debris and reducing the number of cleaning steps. It is a third object of the present invention to provide a dust remover which prevents clogging of debris. It is a fourth object of the present invention to provide a dust remover capable of freely changing the frequency of the sieve so that it can be applied to various kinds of plastics.

[0009]

The powder removing machine of the present invention tilts a double net structure in which upper and lower double nets are combined, supplies a crushed product onto the double net structure, and reciprocates one of the nets. Then, the powder is dropped under the mesh, and the debris is slid on the mesh to reach the end of the mesh and fall into the container. More specifically, a hopper to be charged with the pulverized material, and provided at the lower end of the hopper,
An inclined resin double net consisting of a fixed net and a mobile net,
It consists of a powder container provided under the double mesh. One of the double nets is fixed and the other reciprocates. Motors and speed reducers,
There is a crank to reciprocate the moving net.

[0010]

The upper and lower double-mesh structure is used. The double-mesh is tilted so that one is a reciprocating sieve and the other is a fixed sieve. The crushed product is put on the double net. The upper side is a reciprocating sieve and the lower side is a fixed sieve. The upper sieve must be in motion. You have to make a relative movement. Therefore, the lower sieve may be moved in the opposite direction to the upper sieve. Alternatively, the upper and lower screens may be moved independently. Relative motion occurs between the upper and lower nets. This is important. The powder falls through the mesh of the two meshes. The fragments (pellets) move down the net along the slope and drop. Suppose the debris gets stuck in the upper net. The debris is packed in the mesh so that the longitudinal direction is oriented at right angles to the mesh. Immediately below, there is a lower net that moves relative to each other, so the clogged debris will come out by collision with the lower net.

This makes it possible to reduce clogging. Since there is no clogging, the area of the sieve can be used effectively. Therefore, the area of the sieve portion can be reduced, and the overall size can be reduced. Since it can be directly connected to the discharge port of the crushed material, manpower can be saved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A dust remover according to an embodiment of the present invention will be described with reference to the drawings. 1 is a front view, FIG. 2 is a vertical front view, FIG. 3 is a right side view, FIG. 4 is a plan view, FIG. 5 is an enlarged vertical front view, and FIG.
FIG. 3 is a sectional view taken along line YY in FIG. The dust remover is shown in Figure 1.
As shown in Figure 1, Case 1 which is a rectangular frame,
The drive unit 2, the powder receiving unit 3, the speed switching unit 4, the guide unit 5, and the like. The upper end of the case 1 is a horizontal surface, which is provided with a flange 6. A handle 7 is attached to the side surface of the case 1. There is a through hole 8 on the upper side surface of the case, and a code 9 projects from here and is connected to the motor of the drive unit 2.

As shown in the sectional view of FIG. 2, the upper surface of the case is a hopper. The fragments are put in here. The hopper 10 includes horizontal plates 11 and 12, a rear inclined plate 13,
It has a funnel shape composed of the front inclined plate 14. Rear inclined plate 1
3, a part of the upper end is folded back downward, and this bent piece 15 is inserted into a stopper piece 16 provided on the vertical surface of the case 1. The rear inclined plate 13 can be pulled out upward. The same applies to the front inclined plate 14. A part of the upper end is a bent piece 17 facing downward. Stop piece 1 on the vertical surface of the case
8 is provided, and the bent piece 17 is inserted into this to be fixed. The front sloping plate 14 can also be removed upwards. Handles 19 and 20 are attached to the rear inclined plate 13 and the front inclined plate 14 for removal.

Inside the guide portion 5, a double mesh is obliquely provided. The double net includes an upper net 21 and a lower net 23. The upper net 21 is a quadrilateral net and is attached to the upper frame 22. The upper frame 22 can diagonally reciprocate the guide portion 5. The lower net 23 is attached to the lower frame 24. Lower frame 24
Is fixed to the side wall of the case 1 by screws 25 and 26.

The upper frame 22 can move the guide portion 5 obliquely, but it reciprocates by the geared motor 27 of the drive portion 2. The geared motor 27 is a motor including a speed reducer. The U-shaped member that holds the geared motor 27 is fixed to the case 1 by a screw 28 (FIG. 1). The output shaft 29 of the geared motor 27 rotates at an appropriate speed. The output shaft 29 has a circular crank block 30.
Is attached. 1 on the circumference of the crank block 30
A vertical hole 31 in the axial direction is drilled at the location. Pin 3 in the vertical hole 31
2 is fixed. A pulling piece 33 is provided on the upper end of the upper frame 22.
Is stuck. The pulling piece 33 has a lateral hole 34 that is long in the lateral direction. The length of the lateral hole 34 is longer than the diameter of movement of the pin 32. When the output shaft 29 rotates at the rotational angular velocity of Ω, the crank block 30 also rotates at the rotational angular velocity of Ω.

Although the pin 32 moves left and right in the lateral hole 34,
The upper frame 22 itself reciprocates up and down. Up and down reciprocating motion is indicated by PsinΩt. P is the distance between the center of the pin 32 and the center of the output shaft 29. The lateral movement in the lateral hole 34 is given by PcosΩt. Geared motor 27
The rotation speed of can be changed by the speed switching unit 4. In this example, the motor rotation is 0 RPM to 360 RP
Any value between M can be taken continuously.

As shown in the plan view of FIG. 4, the speed switching unit 4 has a photograph 35 and a switch 36. Switch 3
Reference numeral 6 is a switch for switching between an operating state and a stopped state.
By rotating the camera 35, the speed can be continuously changed from high speed to stop. Panel 37 has
There is a hole 39 for taking out the code 38. Code 38
Is connected to commercial power.

Since the geared motor 27 rotates at Ω, the upper frame 22 and the upper net 21 reciprocate diagonally. The stroke is 2P, but in this example, 2P = 20 mm. The velocity V = PΩsinΩt. In this example, the upper net is moving and the lower net is stationary. Since the relative motion may be given, the upper net and the lower net may be moved in opposite directions. In this example, the lower net has a wider mesh, but this may be reversed. What is important is that there is relative movement between the upper and lower nets.

Since the crushed material of the runner is charged from the hopper 10, the crushed particles roll on the net and come out to the outlet 40. The powder passes through a double mesh and enters the powder receiving portion 3 placed below. The powder receiving portion 3 has a drawer 54, and when the powder is accumulated to some extent, the powder is withdrawn and discarded. The drawer 54 is provided with a stopper plate 55 so that it can be prevented from coming off. There is no need for a clasp. However, irregular debris may get stuck in the upper net. The upper net reciprocates, but it is difficult to remove debris with such vibration. If the clogged part of the debris increases, the part through which the powder passes decreases,
The ability to sort powder decreases.

However, in the present invention, since the lower net does not move and only the upper net moves, the lower end of the clogged debris collides with the lower net,
Receive an upward shock. For the debris to fly upwards,
Move away from the mesh. In other words, even if it becomes clogged, it can be removed. This is different from conventional vibrating screens. The present invention can effectively prevent clogging due to the structure of the upper and lower double nets that relatively move. FIG. 6 is a cross-sectional view of the mesh portion, and the lower mesh is a metal mesh having a wide mesh.
The upper net is a fine nylon net. The sides of the upper frame are in the guides, which are movably supported by a suitable number of bearings 42,43.

FIG. 5 is a sectional view showing the state of selection. Only powder passes through the mesh. The debris passes over the net. Part of the powder comes out at the debris outlet 40. If the net is wide enough, no powder will come out of the outlet. This is a perfect classification. However, if the net is too wide, the device becomes large. Although the device of the present invention has a small mesh area,
It is sufficient because the amount of crushed material input is small and it does not clog.

The outlet is shown in the right side view of FIG. A box for receiving debris is provided here. The debris collected here is
Reuse. Discard the powder as it cannot be reused. Next, in the apparatus of the present invention, the speed and the classification rate depending on the processing time were measured, and the results will be described. Table 1 shows the relationship between the speed scale and the rotation speed.

[0023]

[Table 1]

As described above, the speed scale and the rotation speed are not in a proportional relationship. Of course, it can be proportional. The processing capacity increases with speed, but if the speed is too high, the powder will come out of the outlet, and the classification rate will decrease. When the upper net was SUS, the pulverized material did not flow at a speed of 6.5 or less and the treatment was impossible. However, in the case of the nylon net, the pulverized material flowed and could be processed even at a speed of 4 to 5. It is possible, but slow and not practical. Below sieve speed (upper mesh speed)
Is expressed by the value of the speed scale.

Table 2 shows the results of measuring the processing capacity by speed. The net used was an upper net of φ0.43 × 15 nylon net of φ0.53 × 10 SUS wire net. The lower net is a φ0.7 × 7.5 SUS net. The stroke (2P) of the screen vibration is 20 mm. The pulverized product is PA (polyacetal). The amount that allows the mesh to be seen at all times was manually input. There is ambiguity because the operator throws in the crushed material while making judgments, but since it is inserted so that it does not overflow in the hopper and the empty state where the whole mesh is visible does not occur, this is The processing capacity can be measured.

[0026]

[Table 2]

There is not much difference between nylon and SUS if the speed is 6.5 or more. However, nylon has a slightly higher processing capacity during high-speed movement. Note that the processing capacity here is not the classification capacity.
The processing capacity is the maximum flow rate that can keep the crushed material flowing without the hopper overflowing. There may be a case where powder is mixed and discharged at the debris outlet. Figure 7
The graphs show the processing capacities when the upper net is made of nylon (φ0.43 × 15) and SUS. The unit of the vertical axis is kg / H.

Next, the classification rate depending on the material of the net was examined when the speed was set to 8.5 and 7.5. The classification rate is defined by Y / W, where W is the total amount of powder and Y is the amount of powder that has passed through the net and is stored in the powder receiving portion. This was measured by the following method. The crushed pieces are received at the crushed piece outlet 40 and manually passed through a sieve again to separate the powder, and the amount of this powder is Z. Z and powder amount Y in the powder receiving part
Is obtained by adding W. The sieve used at this time uses the same material and mesh as the upper mesh. Since it is separated by hand, 100% separation should be possible.

FIG. 8 shows the result for the case of 8.5. FIG. 9 shows the result for the case of 7.5. The lower net is φ
0.7 × 7.5 SUS, upper net is φ0.43 × 15 nylon, and φ0.53 × 10 SUS. The pulverized product is a pulverized product of three types of plastic runners, PMMA, PA, and PBT. As for the charging method, a fixed amount was manually added at a fixed time. The horizontal axis is the input amount. If the input amount is small, the classification rate tends to increase. This is natural,
Some are not.

PBT has a low classification rate, and PMMA has a high classification rate. PA is somewhere in between. Thus, the classification rate also depends on the material of the runner. Generally, nylon mesh has a higher classification rate. At higher speeds nylon is particularly good. The higher the speed, the lower the classification rate. This is also natural.

FIG. 10 is a graph showing that the classification rate differs depending on the mesh and speed depending on the material of the runner. It is considered that the material of the upper net affects the classification rate for the following reasons. The present invention contemplates that there are three types of screen clogging. Clams clogging ... clogging due to particles sticking to the mesh Adhesion clogging ... clogging due to particles adhering to the mesh due to the action of static electricity, moisture, oil, etc. If it is made of a resin such as nylon, which has a high elasticity, the mesh will move, so the small debris will be easily removed. For this reason, clogging may be less likely to occur. In the present invention, it is considered that nylon has a higher classification rate than wire mesh because nylon is less likely to be clogged. This is effective when used for the upper network. Since the lower net flies the clam fragments, it may be either wire mesh or nylon.

[0032]

The dust remover of the present invention uses the upper and lower double nets, one reciprocating and the other stationary. The double mesh prevents debris from clogging the mesh. Once clogged, the fragments move out of the mesh due to the relative motion of the mesh. Since it is not clogged, the effective area of the sieve does not decrease with time. Since the effective reduction of the screen area does not occur, the mesh area can be reduced. Therefore, the device can be downsized. Because it can be made small, it can be placed under the discharge port of the crusher. This is important.

In fact, the device described as an example is only 25 cm high. The outlet of the crusher has a height of 2 downwards.
Although on the order of 5 to 60 cm, the device of the present invention can be installed directly below the outlet. By placing this device at the discharge port of the crusher, crushing of the runner and separation of powder can be performed continuously at one time. There is no need for the troublesome work of accumulating the crushed material in a bucket or the like and then putting the crushed material into a dust remover installed at another place as in the conventional case. It is extremely effective in promoting labor saving in plastic molding plants.

Further, since it is hard to be clogged, maintenance and management become easy. Since the debris always clogging the mesh in the conventional flat plate sieve, it was necessary to turn it over, hit the mesh, and rub it to remove the clogging, which required cleaning. The present invention is also excellent in this respect. The net of the present invention is made of a resin having a high elasticity (for example, a net made of nylon) instead of a metal net or punching metal as in the conventional device. Therefore, the clam clogging, which is one mode of clogging, is unlikely to occur. Since the fragments of the plastic runner are simple in shape, they are likely to cause clam clogging, but the present invention is less likely to cause such clogging. Since the net of the present invention is difficult to be clogged with debris from the beginning and is a double net, it is easy to remove the clogged debris from the net.

[Brief description of drawings]

FIG. 1 is a front view of a dust remover according to an embodiment of the present invention.

FIG. 2 is a vertical sectional front view of the dust remover according to the embodiment of the present invention.

FIG. 3 is a right side view of the same dust remover.

FIG. 4 is a plan view of the same dust remover.

FIG. 5 is an enlarged vertical sectional view of the same dust remover.

6 is a cross-sectional view taken along line YY in FIG.

FIG. 7 is a graph showing the results of measuring the processing capacity as a function of the speed of the screen when nylon and SUS are used as the upper net.

FIG. 8: When the speed of the sieve was 8.5, the mesh was SUS,
Nylon and crushed runner-PMMA, PA, PB
The graph which shows the result of having measured the classification rate as a function of the input amount as T.

FIG. 9: When the speed of the sieve is 7.5, the mesh is SUS,
Nylon and crushed runner-PMMA, PA, PB
The graph which shows the result of having measured the classification rate as a function of the input amount as T.

FIG. 10 is a graph showing changes in classification rate when the speed of the sieve, the plastic material, and the net material are changed. The white bar graph has a speed of 7.5, and the shaded bar graph has a speed of 8.5. The upper net is SUS and nylon. The average amount of the charged amount is 3 kg / 5 min to 1 kg / 5 min.

[Explanation of symbols]

 1 case 2 drive part 3 powder receiving part 4 speed switching part 5 guide part 6 flange 7 handle 8 through hole 9 code 10 hopper 11 lateral plate 12 lateral plate 13 rear slant plate 14 front slant plate 15 bent piece 16 stop Piece 17 Folding piece 18 Stopping piece 19 Grip 20 Grip 21 Upper net 22 Upper frame 23 Lower net 24 Lower frame 25 Screw 26 Screw 27 Geared motor 28 Screw 29 Output shaft 30 Crank block 31 Vertical hole 32 pin 33 Lifting piece 34 Horizontal hole 35 36 switch 37 panel 38 code 39 hole 40 debris outlet 42 bearing 43 bearing

[Procedure amendment]

[Submission date] February 28, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 10

[Correction method] Change

[Correction content]

[Figure 10]

Claims (2)

[Claims] 1. A hopper to which a crushed product obtained by crushing a runner is to be charged, an inclined double net provided immediately below the hopper and having an upper net and a lower net, and passed through the net provided below the double net. The lower net of the double net is stationary and is put into the hopper, including the powder receiving part for storing the powder, the driving part for reciprocating the upper net of the double net, and the speed control part for controlling the driving speed. A runner-a powder remover characterized by separating powder and fragments from a crushed product. 2. A hopper into which a crushed material obtained by crushing a runner is to be charged, an inclined double net provided immediately below the hopper and having an upper net and a lower net, and passed through the net provided below the double net. It includes a powder receiving part for storing powder, a driving part for reciprocating the upper net of the double net, and a speed control part for controlling the driving speed. The upper net is a resin net, and the lower net of the double net is A powder remover, which is stationary and is configured to separate powder and debris from a runner-crushed product that is put into a hopper.