JPH0422761B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a powder feeder that once receives powder from a hopper into a receiving hole of a rotating feed drum and then discharges the powder into a container to supply the powder.

<Prior art> Conventionally, when powder is fed in small portions using a powder feeder, as shown in Fig. 6, the powder is measured on the side circumferential surface.
In order to once fill powder into a rotating supply drum 2 provided with a receiving hole 1 for subdivision, the powder is filled into the receiving hole by rotation of one stirring blade 4 in an adjacent hopper 3 and vacuum suction. was. However, if the depth of the receiving hole 1 is increased, especially when performing high-speed filling or in the case of powder with poor fluidity, there is an inconvenience that the prescribed amount of powder cannot be filled into the receiving hole from the hopper, that is, only an insufficient amount is supplied. There was a drawback that caused Therefore, in the vacuum holding zone until the powder supplied to the receiving hole 1 reaches the position where it is filled into the container 5, the powder is deaerated by the vacuum and becomes compacted, causing caving in the receiving hole 1, surface peeling, and This caused powder to fall out of the receiving hole 1, resulting in a decrease in filling accuracy and an inability to measure the stability of the filling amount. Further, in order to compensate for the insufficient filling amount, it is necessary to further deepen the receiving hole 1, and if the receiving hole 1 is made deeper, the above-mentioned condition will become even worse. For this reason, if the amount of powder to be subdivided is large, the predetermined amount cannot be supplied to the container 5 at once, and the purpose is achieved by supplying half the amount twice, but this requires two feeding machines or reduces the capacity by half. I had to let it happen. In addition, this requires time and effort for management.

<Object of the Invention> The present invention solves the drawbacks of the above-mentioned prior art, and makes it possible to receive a predetermined amount of powder even when feeding powder at high speed, when handling powder with poor fluidity, and when making a deep receiving hole. The purpose of the present invention is to provide a powder feeder that can reliably fill a hole and stably supply an accurate amount of powder at high speed.

<Structure of the Invention> The present invention rotates a supply drum in which a plurality of powder receiving holes are formed at regular intervals on the side circumferential surface, and fills the receiving holes with powder at a position where it comes into sliding contact with a powder hopper. The powder feeder is configured to discharge the powder into the container at another rotational position, and the hopper is provided with two or more rotating blades for pushing the powder into the receiving hole, and each rotating blade is used to discharge the powder into the container at two or more positions. , the powder feeder is characterized in that the powder is forced into each receiving hole at least twice.

<Example> Figure 1 is a longitudinal sectional view of a powder feeder showing an example.
Figure 2 is a cross-sectional view of Figure 1, Figure 3 is a cross-sectional view showing how the receiving hole is filled with powder at position A in Figure 1, and Figure 4 is a sectional view showing how the receiving hole is filled with powder at position B in Figure 1. FIG. 5 is a sectional view showing the state, and FIG. 5 is a front view showing the slide valve for switching between vacuum and compressed air.

The powder feeder includes a supply drum 2 which is intermittently rotated at a constant angle and has powder receiving holes 1 formed on the outer peripheral surface of the disk shape at intervals of the angle.
It consists of a supply hopper 3 for supplying powder to the receiving hole 1 of the drum 2, and rotating blades 41, 42, etc. for constantly stirring the powder in the hopper 3 and pushing it into the receiving hole 1 while maintaining a constant state. has been done. The powder is introduced into the supply hopper 3 from an upper hopper (not shown), and is then introduced into each receiving hole 1 of the supply drum 2.
is filled with the container 5, and when it rotates downward, the container 5
is discharged. The supply drum 2 has a solid-gas separation filter 7 in the receiving hole 1, and compressed gas is sucked in or discharged from the ventilation path 8 through the filter 7.
A movable adjustment member 9 moves within the hole 1 with the filter 7 attached, and adjusts the depth of the hole 1 as necessary. 10 is an intermittent rotation drive shaft. By this intermittent rotation drive shaft 10, each receiving hole 1 of the supply drum 2 is sequentially and intermittently rotated while stopping at each position A, B, C...L in FIG.

The supply hopper 3 is provided with an opening 11 at its bottom. This opening 11 has at least the supply drum 2
The two stopping positions of the receiving hole 1 (in Fig. 1, A,
The size includes the stop position shown in B. on the other hand,
There are two or more rotating blades 41, 4 in the supply hopper 3.
2 will be provided. These rotating blades 41 and 42 are connected to the hopper 3.
These blades are for pushing the powder into the receiving hole 1 at the stop position while stirring the powder inside, and the tip of the blade reaches near the opening 11. Although the number and size of rotating blades are not particularly limited,
It can be determined based on the size of the hopper 3, the type of powder, how many times the receiving hole 1 can be completely filled with powder, etc. The relationship between the rotating blades and the stopping positions of the receiving hole 1 is such that the stopping positions of the receiving hole 1 correspond to the positions where the tips of the blades reach the vicinity of the openings 11, respectively. Of course, the number of rotating blades and the opening 1 of the receiving hole 1
It is not necessarily necessary that the number of stopping positions at 1 corresponds to the number of stopping positions at the opening 11 of the receiving hole 1, and if the number of stopping positions at the opening 11 of the receiving hole 1 exceeds the number of rotating blades, for example, when there are two rotating blades,
The number of stopping positions may be three. In this embodiment, there are two rotating blades and two stopping positions A and B corresponding to each other. In this embodiment, larger rotating blades 41 and smaller rotating blades 42 are provided in the direction of rotation of the supply drum 2.

To fill the powder into the receiving hole 1, first, the powder is pushed into the receiving hole 1 by the rotary blade 41 at the position A (of course, in this case, vacuum suction is also performed at the same time) as shown in Fig. 3. While the receiving hole 1 is moving to the next stop position B, the pushed powder is compacted by vacuum suction and causes a depression. Then, at the next stop position B, the powder is pushed into the depressed area by the rotating blade 42 that provides additional assistance, and the powder is replenished.
(See Figure 4), a predetermined amount of powder is filled. Excess powder is removed by a mass cutting plate 12. The receiving hole 1 filled with powder reaches G via positions C, D, E, and F while being prevented from falling off by vacuum, and is discharged into the container 5 by compressed air at position G. The reason why the rotary blade 42 is made smaller than the blade 41 in the embodiment is because it can be made smaller since it only needs to fulfill the role of replenishing insufficient filling. Moreover, by doing so, it is possible to prevent problems caused by increasing the volume of the supply hopper 3 and the area of the opening 11. Also, rotating blades 41 and 42
By adjusting the rotational speed of both blades, the blades can be provided close to each other to the point where their rotational trajectories overlap. The rotational speed of the rotary blades 41 and 42 can be changed depending on the stopping time of the receiving hole 1, but in the embodiment, the speed is such that eight blades pass through the receiving hole 1 while the receiving hole 1 is stopped. Furthermore, rotating blade 4
The rotation directions of 1 and 42 may be the same or opposite.

Slide valve 13 (second
5) is in contact with the supply drum 2, and as the supply drum 2 rotates, vacuum suction for powder filling is performed at the position of the hole 13a (corresponding to the stop positions of A and B of the receiving hole 1). , Vacuum suction for powder retention is performed at the hole 13b position (corresponding to the stop position C, D, E, F of receiving hole 1), and at the hole 13c position (corresponding to the stop position G of receiving hole 1). Compressed air is discharged, and compressed air for cleaning the filter 7 is discharged at the position of the hole 13d.

<Effects> The present invention has the above-described configuration, in which two or more rotating blades are provided in the hopper for pushing the powder into the receiving hole, and each rotating blade pushes the powder into each receiving hole at least twice at two or more positions. Since the amount not filled at the first position is replenished at the next position or the position after that, it is possible to reliably receive the specified amount, especially when feeding at high speed or when handling powder with poor flowability. Can be filled and dispensed. In that case, even though the receiving hole stops at two or more positions and receives the powder supply, no extra time is required for this, and the number of stops of rotation of the supply drum 2 is reduced. There's no need to double it. That is, according to the present invention, an accurate amount can be stably supplied without reducing the powder supply rate.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a powder feeder showing an embodiment;
Figure 2 is a cross-sectional view of Figure 1, Figure 3 is a cross-sectional view showing how the receiving hole is filled with powder at position A in Figure 1, and Figure 4 is a sectional view showing how the receiving hole is filled with powder at position B in Figure 1. 5 is a front view showing a slide valve for switching between vacuum and compressed air, and FIG. 6 is a sectional view showing a conventional device. 1... Powder receiving hole, 2... Supply drum, 3...
Supply hopper, 5... Container, 7... Solid-gas separation filter, 11... Opening, 41, 42... Rotating vane.

Claims (1)

[Scope of Claims] 1. A supply drum having a plurality of powder receiving holes formed at regular intervals on its side circumferential surface is rotated, and powder is filled into the receiving holes at a position where it comes into sliding contact with a powder hopper,
The powder feeder is configured to discharge the powder into the container at another rotational position, and the hopper is provided with two or more rotating blades for pushing the powder into the receiving hole, and each rotating blade is used to discharge the powder into the container at two or more positions. , at least 2
A powder feeder characterized in that the powder is pushed into each receiving hole twice. 2. The scope of claim 1, in which two rotating blades are provided to perform powder supply in two stages, and in the second stage supply, the insufficient filling amount in the first stage supply is supplemented by an auxiliary rotating blade. Powder feeding machine according to item 1. 3. The powder feeder according to claim 1 or 2, wherein the powder is filled into the receiving hole by vacuum suction and pushing by a rotating blade.