JPH051788Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention is a feeding device used for quantitatively measuring various powders such as plastic powder, ceramic powder, cement, grain flour, and grain grains, and more specifically, a hopper for storing powder and granules. and a screw feeder for taking out a fixed amount of powder or granular material from the hopper. [Prior art] In this type of powder or granular material quantitative feeding device, whether batch-type quantitative metering or continuous quantitative metering in which the amount of supply per unit time is constant, the metering accuracy must be maintained. In order to improve the performance, it is necessary to maintain a constant supply amount per unit time from the screw feeder. This is because in a screw feeder, although the amount of powder and granules discharged from the screw feeder in one rotation of the screw is theoretically constant, in reality, the powder and granules may collapse or Due to excessive flow such as flushing, the discharge amount per unit time fluctuates, and as a result, if powder and granules are simply discharged and supplied from the screw feeder, the supply amount will naturally decrease. is pulsating. This kind of pulsation in the supply amount is not only a fatal drawback in the case of continuous quantitative measurement, but also in the case of batch-type quantitative measurement, after the measurement signal is sent, it is The time lag until the powder supply is actually stopped causes large variations in the head. Therefore, in the past, an auxiliary hopper was provided, which consisted of a flow rate adjusting plate and a first gate, which acted on the powder and granular material falling and being discharged from the screw feeder.
Some methods are known in which attempts are made to prevent fluctuations in the supply amount due to pulsations in the amount discharged from the screw feeder by retaining powder and granules in an auxiliary hopper (for example, Japanese Utility Model Publication No. 61-4823). Publication No.). Further, at the transfer end of the screw feeder,
A dispersing device is provided to disperse the powder from the screw feeder in the direction of rotation of the screw.
There are also known devices that smooth out the pulsations in the supply amount by dispersion (for example, Utility Model No. 61-36535).
Publication No.). [Problem to be solved by the invention] However, in the case of the former, the amount of powder in the auxiliary hopper fluctuates due to the pulsation of the discharge amount from the screw feeder, and the weight of the powder in the auxiliary hopper fluctuates. Because the discharge force from the auxiliary hopper changes, it has not been possible to suppress fluctuations in the supply amount to a sufficiently small level. In addition, when using the latter method, the dispersing tool acts on the unstable powder or granules during discharge, and as a result, the dispersion by the dispersing tool is unstable, so it is still not possible to suppress fluctuations in the supply amount to a sufficiently small level. Ta. The purpose of the present invention is to provide a powder supply device using a screw feeder that can easily control the amount of powder and granule transported, and to reduce the amount of powder supplied due to the pulsation of the amount of powder discharged from the screw feeder. The point is to minimize the fluctuations in . [Means for Solving the Problems] The technical means of the present invention taken to achieve the above object includes a hopper for accommodating powder and granules, a screw tube extending in series with the hopper, and the screw tube. A powder and granular material quantitative supply device configured as a screw feeder for taking out a fixed amount of powder and granular material in the hopper from a screw housed in a cylinder, comprising the configurations described in [A] to [C] below. That's what happened. [B] At the transfer end of the screw feeder,
A retention chamber for retaining the powder and granular material from this screw feeder is provided in series, and by rotating around an axis along the inside and outside directions of the retention chamber, the scraper removes the retained powder and granule in the retention chamber. A rotating scraper is provided for scraping and discharging the liquid to the outside of the retention chamber. [B] The rotary scraping tool includes a main body that also serves as a part of the chamber forming wall of the retention chamber, and a scraper provided on an inward surface of the main body facing inward of the retention chamber scrapes the inside of the retention chamber. The powder and granular material is continuously scraped out from the inward surface side to the back surface side thereof through a discharge port formed in the main body. [C] The amount of scraping out per unit time of the rotary scraping tool is configured to be approximately the same as the amount of feeding out per unit time of the screw feeder. [Effects] The effects of taking the above technical means are as follows. a Because a retention chamber for temporarily storing the powder and granular material supplied by the screw feeder is connected to the transfer end of the screw feeder, there may be some pulsation in the supply of powder and granular material by the screw feeder. Even if there is a change in the supply amount of powder or granular material due to the pulsation, it does not directly affect the conveyance on the downstream side of the transfer direction from the holding chamber, and as a result, the conveyance by the screw feeder is It is possible to suppress the influence of pulsation associated with b The powder and granular material in the retention chamber is constantly removed by positioning the scraper of the rotary scraper facing the retention chamber and rotating around an axis along the inner and outer directions of the retention chamber. Since the particles are continuously scraped and discharged, there is no interruption in the scraping and discharge of the powder particles by the rotating scraper, and the particles are scraped out in a continuous flow state. c Furthermore, the amount of scraping with the rotating scraper is
Since it is set to be the same as the feed rate of the screw feeder, the amount of scraping per revolution changes due to compaction of powder or granular material in the retention chamber or excessive scraping amount, resulting in pulsation. It is also possible to avoid the situation from occurring. [Effects of the invention] Due to the effects described in a. to c. above, according to the present invention, scraping and discharge by the rotary scraper is stabilized regardless of the pulsation of powder discharge from the screw feeder, By performing this stable scraping and discharging without interruption, the powder and granular material can be quantitatively supplied in a stable continuous flow, and fluctuations in the supply amount can be suppressed to a minimum, thereby improving the accuracy of quantitative measurement. [Example] Next, an example of the present invention will be described based on the drawings. As shown in FIG. 5, a hopper 1 that accommodates powder and granules, a screw feeder 2 in a horizontal position for taking out a fixed amount of the powder and granules in the hopper 1 from the bottom of the hopper, and a retention chamber 3; A rotating scraper 4,
The granular material quantitative supply device is equipped with a gate 5, and the hopper 1 is provided with a granular material that rotates around a horizontal axis to agitate the granular material in the hopper 1.
A stirring blade 6 is provided to equalize the amount of powder and granular material flowing down from the hopper 1 to the screw feeder 2. As shown in FIGS. 1 and 2, the screw feeder 2 includes two screws 2A having the same structure that rotate in the same direction while being in mesh with each other, a screw tube 2B that is externally mounted on these screws, and It consists of a motor 2C that drives both screws 2A. As shown in FIGS. 1 and 2, the retention chamber 3 is formed at the end of the end processing member 2a at the transfer end of the screw cylinder 2B of the screw feeder 2. As shown in FIGS. 1 to 3, the rotary scraper 4 has a disc-shaped main body that rotates around an axis X along the inner and outer directions of the retention chamber 3 in conjunction with the screw feeder 2. 4A is provided to form a wall surface portion of the wall surface of the retention chamber 3 that faces the end surface of the screw 2A, and the powder inside the retention chamber 3 is disposed at a plurality of locations in the circumferential direction of the main body 4A as the main body 4A rotates. A scraper 4B along the radial direction for scraping the granules and a discharge port 4C for discharging the scraped granules are formed, and in conjunction with the screw feeder 2, the inside of the retention chamber 3 is formed. It is configured to scrape and discharge the powder and granular material as a continuous flow. In addition, in the center of the main body 4A, there is a cone 4D that disperses the powder and granules from the screw feeder 2 outward in the radial direction to make the circumferential distribution of the powder and granules uniform in the retention chamber 3. It is provided. Therefore, although the amount of feed per unit time to the retention chamber 3 by the screw feeder 2 changes in a sine curve as shown by line A in FIG. The amount of scraping per unit is
As shown by the line in FIG. 4, there is no change, or even if there is a change, it is only slight. The means for interlocking the main body 4A of the rotary scraper 4 with the screw feeder 2 is means for driving the main body 4A with the motor 2C of the screw feeder 2, and specifically, of,
The motor 2C is connected to the motor 2C via the shaft 6a of the stirring blade 6.
This is a means for interlocking with the output shaft 2b. Of course, the amount of scraping and discharging per unit time by the rotating scraper 4 is as shown in FIG. 4, as shown in FIG.
The supply amount is set to be the amount supplied to The scraping amount per unit time by the rotating scraper 4 is determined by the length of the scraper 4B, the protruding length of the scraper 4B from the main body 4A,
The length, protrusion length, and number of the scrapers 4B are determined by the number of scrapers 4B and the number of rotations.
When the rotation speed is 280 rpm, the rotation speed is 82 to 816 rpm, which is several times the rotation speed of the screw 2A. As shown in FIGS. 1 and 2, the gate 5 is fitted onto the shaft 4a of the main body 4A of the rotary scraper 4 and moved in the axial direction, thereby closing the end of the screw tube 2B. The processing member 2a is used as a valve seat 7 to open and close the discharge port 9 from the rotary scraper 4 to the discharge passage 8. It is biased closed by a spring 10, and is biased by an air cylinder 11 (a solenoid may also be used). It is something that is liberated against the tide. And this gate 5
The surface 5a that comes into contact with the valve seat 7 is formed into a tapered surface in order to make line contact with the valve seat 7 and improve the obstructing property. According to the configuration of the above embodiment, the powder and granules are supplied from the screw feeder 2 to the retention chamber 3, and the powder and granules supplied into the retention chamber 3 are made into a continuous flow by the rotary scraper 4 and scraped and discharged. Therefore, as shown in FIG. 4, the scraping discharge amount per unit time, that is, the supply amount can be made constant or almost constant. Moreover,
Since the gate 5 is provided and the gate 5 is energized to close instantly, the head can be made very small. Hereinafter, apparatus A equipped with only the screw feeder 2, apparatus B additionally provided with a gate 5, apparatus C additionally provided with a rotary scraper 4, and apparatus of the above embodiment additionally provided with a rotary scraper 4 and a gate 5. Using each of D, measurements were performed with the measurement settings set to 5g, 10g, and 15g, and a measurement test was conducted to determine the deviation (δ), variation (R), and head (h). The results are shown in Table (a). The granular material is flour, and the data is 50
This is the average of 2 tests. In addition, in order to keep the measurement time almost constant in the test with each measurement setting value, the rotation speed (rpm) of the screw 2A was set to 28.5, 57.6, and 86.4 at large, medium, and small drive voltages as motor 2C, respectively. I used something like this.
The flow rate in the table is the amount supplied per unit time.

[Table] From the above test results, it can be seen that the provision of the retention chamber 3 and the rotating scraper 4 generally improves the measurement accuracy, and furthermore, the provision of the gate 5 further improves the measurement accuracy. Another embodiment of the present invention will be shown below. This is carried out by using only one screw 2A of the screw feeder 2. Note that although numbers are written in the claims section of the utility model registration for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of the drawing]

The drawings show an embodiment of the apparatus for quantitatively feeding powder and granular material according to the present invention, in which FIG. 1 is a vertical cross-sectional side view of the main part, FIG. 2 is a vertical cross-sectional plan view of the main part, and FIG. 3 is a cross-sectional view of the main part. , FIG. 4 is a graph showing the change in emission amount over time, and FIG. 5 is a schematic diagram of the overall configuration. 1...Hotsupa, 2...Screufeeda, 2
A...Screw tube, 2B...Screw tube, 3...
...Retention chamber, 4...Rotating scraper, 4A...Main body, 4B...Scraper, 4C...Discharge port.

Claims (1)

[Claims for Utility Model Registration] A hopper 1 for storing powder and granules is provided, and a screw tube 2B extending in series with the hopper 1, and a screw 2A housed in the screw tube 2B are provided with a hopper 1 for storing powder and granular material. A powder and granular material quantitative supply device that includes a screw feeder 2 for taking out a fixed amount of powder and granular material, and has the configurations described in [A] to [C] below. [A] At the transfer end of the screw feeder 2, a retention chamber 3 for retaining the powder from the screw feeder 2 is provided, and an axis X along the inner and outer directions of the retention chamber 3 is provided. A rotary scraping tool 4 is provided which scrapes the powder particles staying in the retention chamber 3 by rotating around it with a scraper 4B and discharges it out of the retention chamber 3. [B] The rotary scraping tool 4 is arranged in the retention chamber 3.
A scraper 4B provided on the inward surface of the main body 4A that faces inward of the retention chamber 3 scrapes the powder and granules in the retention chamber 3. It is configured to continuously scrape out from the inward surface side to the back surface side thereof through a discharge port 4C formed in the main body 4A. [C] The amount of scraping out per unit time of the rotary scraping tool 4 is configured to be approximately the same as the amount of feeding out per unit time of the screw feeder 2.