JPH0132129B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a supply and discharge device for sending out powder and granular materials, and is capable of quantitatively controlling the amount of adhesion over a wide range regardless of the amount of delivery. This is a table feeder that can stably supply and discharge powder that is strong or contains agglomerates.

[Prior art]

There are various types of feeding and discharging devices for powder and granular materials, but among them, the table feeder illustrated in Figure 5 has a simple structure, has few moving parts that can easily cause trouble, and is easy to adjust and change the feed rate. It has many advantages, such as being easy to make and changing the design to make it larger, and has been used in various fields that handle powder and granular materials for a long time. Various improvements have also been made to suit the use in each field. Especially when dealing with powders and granules that have strong adhesion or coexist with agglomerates, it is necessary to apply shaking vibration or impact to the hopper or to blow air into the hopper to ensure smooth delivery onto the table. Methods and members for this purpose have been added, such as feeding a rotary agitator, or providing a rotating stirring member or a scraping blade.

[Problem that the invention seeks to solve]

Despite the various improvements mentioned above,
There were problems with powders and granules that had strong adhesion and cohesive properties. That is, when such raw materials are fed by the table feeder, as shown in FIG. There are serious problems such as not being able to smoothly deliver the fluid, making stable supply and discharge impossible, or making it difficult to deliver due to blockage, and these problems have not yet been solved by the above-mentioned measures. The object of the present invention is to solve these problems and provide a table feeder with excellent quantitative performance.

[Means to solve the problem]

In the present invention, a raw material hopper is disposed above the rotation center of the rotary table, a discharge tube is fitted and connected to the lower opening of the hopper separately from the hopper, and the discharge tube is connected to the rotary table. By rotating the hopper while holding it at an appropriate distance from the upper surface, it is possible to smoothly feed the raw material from inside the hopper.Also, to maintain the distance between the two members, a part made of a slidable material is used. A spacer having a notched groove is disposed in the spacer, and the pressure of the raw material flowing down from above is used to equalize the filling within a certain volume, thereby achieving stable quantitative supply and quantitative discharge.

[Effect]

First, the material in the hopper is placed in the vicinity of the opening to alleviate or suppress the compaction phenomenon caused by the weight of the material above in a stationary state before being sent out from the opening, thereby eliminating the causes of blockage such as bridging and rat holes. The purpose is to prevent or release the blockage, and when the discharge pipe provided at the lower opening of the hopper is rotated, the powder layer itself packed from the hopper to the discharge pipe is sheared at this junction. This shearing action transmits motion from the raw material in this vicinity to the raw material in the lower opening of the hopper above, smoothing the contact between raw material particles and suppressing adhesion and aggregation between particles and the wall surface and between particles. It also prevents the formation of agglomerates and smoothes the downward flow.
From this state, when the table rotates in the direction of the arrow in the figure and supply/discharge is started, the relative movement of the raw material particles becomes active, making it possible to send out more stably and smoothly. Second, since the discharge tube is located at a position offset from the center of the rotary table, the entire surface of the table in contact with the lower opening moves in one direction.
In addition, compared to the center position, it has a much faster transfer force and, thirdly, the spacer and notch groove provided between the opening and the table surface allow the transfer to be performed at the table surface. The aim is to temporarily suppress the delivery and make the delivery amount uniform as a whole. In other words, the material flowing down from above is prevented from spreading due to the angle of repose of the material on the table surface by the spacer provided below the discharge tube.
Further, in this space, in addition to the weight of the upper raw material, the raw material is compressed and packed by the moving force caused by the rotation of the discharge tube and table, and is continuously sent out from the notch groove with a uniform density. As described above, the first effect due to the rotation of the ejection tube, the second effect due to the off-center position of the rotary table, and the third effect due to the provision of the spacer and notch groove are as follows. In addition to smooth feeding of raw materials, it also enables uniform and stable supply and discharge. Then, the raw material sent out from the notch groove of the spacer is sent on a rotary table, scraped off by a scraper, and supplied to the next process or discharged and collected.

〔Effect of the invention〕

As described above, the effects of the present invention are that it is possible to secure a flow path in the hopper by suppressing the adhesion, aggregation, and coagulation of raw material particles that are likely to occur in the hopper, which can lead to blockages such as rat holes, and to secure a flow path in the hopper. To be able to stably and smoothly feed raw materials. Then, for the raw material sent onto the rotary table surface, the spacer part and the notch groove perform a compaction filling action to equalize the raw material density and constant the delivered volume, and the amount is transferred to the rotary table. It is possible to send out a fixed amount, and to be able to supply and discharge a fixed amount. In addition, the structure is simple, and the powder contact parts, which are particularly prone to failure, are simple.
It has the advantage of being extremely easy to maintain and clean, and having a large degree of freedom when making design changes for scale-up and the like.

〔Example〕

An embodiment will be described with reference to FIGS. 1 and 2. Reference numeral 15 denotes a machine base, on which the rotary table 1 is held and a transmission 13 and an electric motor 1 for rotating it are mounted.
4 is installed. And rotary table 1
The raw material hopper 11 provided above is held by a bracket 16 at an appropriate height off the center of rotation of the rotary table 1, and a right cylindrical discharge tube with a slightly larger diameter is connected to the lower opening 18. 4 and connect them by fitting. The dimensions of the gap and the overlapping portion between these two members are sufficient as long as they allow ventilation with the inside of the discharge tube 4 and prevent raw materials from leaking out. And the discharge tube 4
is rotated by four receiving wheels 7, two each rotatably attached to two rotating shafts 8a and 8b, and a belt 6. These two rotating shafts 8
One of a and 8b, 8a, is attached with a pulley 9 as a drive shaft, and is connected to a transmission and an electric motor (not shown) via a belt to transmit rotational driving force, and the other 8b is a driven shaft, which is used for discharging via a receiving wheel 7. It supports the tube 4. These rotating shafts 8
a and 8b are held by brackets 16 and 17. The vertical support of the discharge tube 4 is achieved by placing it on a spacer 2 which is fixed between the discharge tube 4 and the lower rotary table 1 and is slidable on both sides. The spacer 2 has a notched groove 3 having a curved surface extending along the circumference from the inside of the mounting position of the discharge tube 4 to the center of rotation of the rotary table 1.
and a scraper part 10 for scraping. The thickness t of the spacer 2 and the width b of the notch groove 3 affect the amount of supply and discharge, as do the rotational speeds of the rotary table 1 and the discharge tube 4, and are designed appropriately in consideration of these factors. The spacer 2 is fixed by being attached to the bracket 16 via the holding rod 12.
Further, near the lower end of the discharge tube 4, an elastic plate piece 5 is attached with one end fixed and the other end free. The elastic plate pieces 5 are effective for scraping out the raw material when it becomes low in the discharge pipe 4 or loosening the lumpy raw material, and the number of the elastic plate pieces 5 may be plural. In addition, the elastic plate piece 5 is made thin enough to be deflected by the agglomerates, so as to reduce the impact upon contact with the agglomerates and minimize the influence on the rotation of the discharge tube 4, thereby reducing the flow of powder and granules.
This is useful in reducing resistance to passage. Also,
One or more partition plates are installed vertically on the lower opening 18 side of the hopper 11 to prevent the raw materials in the hopper 11 from rotating together due to the rotation of the discharge tube 4, and to moderate the powder pressure in the hopper 11. Supporting the hopper 11 is also effective in bringing out the effects of the present invention, and may be adopted depending on the size and shape of the hopper 11.

[Experiment example]

Figure 3 shows the experimental results of this example. The raw material titanium oxide had an average particle size of 0.5 microns.
The powder is extremely cohesive, and can be fed and discharged in a short time using both the conventional table feeder as shown in FIG. It has become impossible. In this graph (in the graph in the figure), the horizontal axis shows the elapsed time (minutes), and the vertical axis shows the integrated value (grams) of the amount of supply and discharge. The rotation speed of the chisel was changed, and the rotation speed of the graph was faster. However, in terms of quantitative performance, as can be seen from the fact that both graphs progressed almost linearly, it was shown that the supply and discharge were stable over time.

[Another example]

As other embodiments, the direction of rotation of the discharge tube 4 may be reversed periodically or intermittently to shake the raw material inside, or the shape of the discharge tube 4 may be slightly expanded downward. These measures, along with measures such as smoothing the powder contact area and making the material less adhesive and less likely to be charged with static electricity, are effective in bringing out the effects of the present invention even more. Furthermore, various design changes may be made to the shape of the spacer 2 and the structure and attachment/support method of the drive section of the discharge tube 4 in accordance with usage conditions, such as making the mechanism more compact and compact. For example, as shown in FIG. 4, a belt 6' that transmits rotational force to the discharge tube 4 is attached to two rotating shafts 8a', 8b' and a receiving wheel 7', and a tension pulley 19 is provided. ', press the discharge tube 4 against the belt 6', and then push the push wheel 20, arm 21, and spring 2
2 may be used to hold the discharge tube 4. In this case, the discharge tube 4 can be attached and detached with a single touch, making maintenance, inspection, and cleaning more convenient.

[Brief explanation of drawings]

1 and 2 are cross-sectional views of essential parts showing one embodiment of the present invention, FIG. 3 is a graph showing experimental results in this embodiment, and FIG. 4 is a cross-sectional view of the main parts of FIG. The embodiment and FIG. 5 each show a conventional example. In the figure, 1...rotary table, 2...spacer, 3...notch groove, 4...discharge tube, 5...elastic plate piece, 10...scraper section, 11...raw material hopper, 18...downward It is an opening.

Claims (1)

[Claims] 1. A raw material hopper 11 is arranged above the center of rotation of the rotary table 1, and a discharge tube 4 is fitted and connected to the lower opening 18 of the hopper 11 separately from the hopper 11. At the same time, a spacer 2 is provided to maintain the distance between the discharge tube 4 and the upper surface of the rotary table 1, and has a notch groove 3 opened on the rotation direction side of the rotary table 1.
A table feeder for powder and granular materials, characterized in that it is configured to be rotated separately from the table feeder. 2. The spacer 2 has a curved surface portion a extending along the circumference from the lower notch groove 3 of the discharge tube 4 with respect to the center of rotation of the rotary table 1, and a scraper portion 10. Table feeder for powder and granular materials as described in Section 1. 3. The table feeder for powder and granular material according to claim 1, wherein one or more elastic plate pieces 5 are attached to the inner lower part of the discharge tube 4 with one end fixed and the other end free.