JPS6233040B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary powder compression molding machine that prevents the upper punch from squeaking when manufacturing tablets and the like.

As is well known, a rotary powder compression molding machine is a machine for manufacturing powder molded products that performs a series of processes from supplying powder to a mortar to molding on a rotating disk. Coupled with the fact that the rotational speed is increasing, the structure of the molding machine itself also causes significant powder scattering around the rotary disk.

The scattered powder reaches the rotating upper part of the upper punch holder and easily enters the small gap between the upper punch and the upper punch, causing a so-called upper punch squeaking phenomenon that interferes with the vertical movement of the upper punch. However, if this phenomenon is left unaddressed, not only the upper punch but also the upper punch raceway plate that guides the upper punch up and down will be damaged.

Damage to the upper punch raceway plate is one of the most fatal molding machine troubles, requiring extensive repair and having an extremely large impact on production, so fundamental countermeasures have long been desired. For example, although refueling is naturally considered as a general countermeasure to such problems, it becomes completely counterproductive in situations where there is a large amount of scattered powder as described above.

In other words, the scattered powder is adsorbed on the oil film surface formed by oil supply, and as the molding machine rotates, it becomes sludge-like.
Furthermore, it becomes a cake-like black dust, and instead of alleviating the squeak, it actually causes the squeak to occur more quickly. If this situation is left unaddressed, there is a danger that the black dust will eventually fall onto the rotary disk and be mixed into the product.

Apart from molded products such as sintered products that do not inherently pose hygiene issues, this is absolutely unacceptable in the production of food and pharmaceutical molded products, such as tablets, etc. Conventionally, it has been a golden rule in pharmaceutical molding machines, ie, tablet machines, that the upper punch section is not lubricated.

Recently, a method has been seen in which the upper and lower ends of the upper punch holder are sealed with oil seals to supply oil to the gap between the upper punch and the upper punch. However, although this method has the advantage that the sliding surface of the upper punch is always covered with a sufficient oil film, on the contrary, the scattered powder effectively adheres to this oil film surface.

The powder that has adhered in this way accumulates at the same time as the surface of the punch is pressed in the oil seal part, and eventually falls off. Although this method has the effect of preventing the upper punch from squeaking, it does not have the effect of preventing the adhesion of scattered powder. It has nothing. Therefore, although this method can be employed for molding sintered products, it is difficult to employ for molding edible molded products, tablets, and the like.

The present invention aims to solve the problems of the conventional molding machine, and has the following configuration.

The rotary disk and the upper punch holder are integrated and are rotatable about a fixed shaft.

A large number of holes are arranged around the circumference of this rotary disk, and the upper punch holder located above the holes is also provided with holes coaxial with the holes, and the upper punch is set in these holes. has been done.

Incidentally, the upper punch raceway plate is fixed to the main body frame side using a set pin or the like so as not to rotate.

An air supply pipe is installed passing through the surrounding wall of the tablet press body (any surrounding wall including the main body ceiling, main body side wall, or surrounding cover), and one end of the air pipe is connected to a clean air generator (not shown). The other end is connected to the air chamber at the top of the upper punch holder.

This air chamber is formed by a cover placed around the upper part of the upper punch holder.
To be precise, it is a space formed by the upper punch raceway plate and the upper punch holder.

An appropriate gap exists between the contact sides of the upper punch holder and the cover.

Next, the air chamber is formed by a cover disposed to surround the rotary disk, and more precisely, it is formed by the rotary disk including the upper punch holder.

Furthermore, there is also an appropriate gap between the tangent sides of the rotary disk and the cover. The air chamber is located in the upper part of the tablet machine body and surrounding walls of the tablet machine body (main body ceiling,
(including the main body side wall, table surface, or surrounding cover).

An exhaust pipe is disposed passing through the peripheral wall of the tablet press body, one end of which is open and connected to the air chamber, and the other end is connected to a dust collector (not shown).

With the above configuration, when clean air is sent from the clean air generator (not shown) through the air pipe, the pressure of the clean air is equalized and positive in the air chamber, and the air gradually passes through the gap. leaks into the room.

At this time, a part of the clean air that has become positively pressurized in the air chamber also enters the gap between the upper punch holder and the upper punch and is sucked in, so the raceway surfaces of the upper punch holder and the upper punch road plate are also maintained in a clean atmosphere. . Next, the air that flows into the air chamber is clean and pressure equalized here as well, and then flows into the air chamber through the gap, and at the same time, it is discharged from the exhaust pipe along with the floating dust generated in the air chamber, and is sent to the dust collector. is attracted and guided to.

In this case, it is best to adjust and set the air volume and pressure of the clean air generator and dust collector so that the relationship between the air pressures in each air chamber is air chamber > air chamber > air chamber. Both interiors of the room can be kept clean.

It should be noted that the gaps are necessarily present in order to avoid rotational friction between the covers 〓 and 〓 and the rotary disk, and do not need to be intentionally provided.

As described above, according to the present invention, there is almost no scattering, mixing, or accumulation of dust on the upper part of the rotary disk, especially around the upper punch holder and around the upper punch raceway plate, which was previously caused by such dust. It is possible to solve problems such as damage to the upper punch and raceway plate caused by increased upper punch squeak and contact squeak.

Next, other embodiments of the present invention will be described.
That is, in addition to the configuration of the above-mentioned embodiment, a groove is provided in the portion of the upper punch raceway plate constituting the air chamber where the upper punch contacts, and this groove is filled with a lubricating oil-impregnated material to prevent the upper punch from squeaking. This is a rotary powder compression molding machine. Of course, even with the configuration of the above-mentioned embodiment, considering the fact that in the past, molding machines were operated without oil lubrication at all and were covered with dust, it is possible to achieve a sufficient effect of improving the upper punch's squeaking by simply removing the dust. As already mentioned, this embodiment creates a situation in which oil can be supplied to the upper punch, thereby further enhancing the effect of preventing the upper punch from squeaking.

That is, by filling the groove provided in a part of the upper punch raceway plate with the lubricating oil impregnated material E34B, each upper punch is sequentially filled with the lubricating oil impregnated material as the rotary disk rotates. By constantly supplying a small amount of oil, the contact surface between the shoulder of the upper punch and the raceway plate, which has particularly high friction, is covered with an ideal minimum amount of oil film, and it is impossible to completely prevent the squeaking of the upper punch. Of course, this will also reduce the life of the upper punch and raceway plate compared to the conventional 2.
It has the great effect of more than doubling the length of time.

In addition, as another embodiment, there is a structure in which a lubricating oil-impregnated material is arranged in a part of the cover constituting the air chamber so as to come into contact with the head of the upper punch. This is exactly the same as the previous embodiment in which a lubricating oil-impregnated material is placed on the portion of the plate that contacts the upper punch, and detailed description thereof will be omitted. Note that it is of course possible to implement the second embodiment and the third embodiment in combination.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view of a main part showing an embodiment of the method for preventing upper punch squeaking in a rotary powder compacting machine according to the present invention. ...rotating disk, ...upper punch holder, ...fixed shaft, ...mortar hole, ...upper punch, ...upper punch raceway plate, ...body surrounding wall, ...air pipe, ...gap, ... Gap, ...exhaust pipe, ...lubricating oil-impregnated material, ...groove, ...lubricating oil-impregnated material,,,
...Air chamber,〓,〓...Cover.

Claims (1)

[Claims] 1. A rotary powder compression molding machine comprising: (1) a clean air generator; (2) an air pipe whose one end communicates with the clean air generator and whose other end communicates with the air chamber described below; (3) ) an air chamber formed by the upper punch raceway plate, the upper punch holder, the upper end of the rotary disk, and the cover, with a gap between the cover and the upper end of the rotary disk; (4) the rotary disk and the cover; (5) an air chamber formed by the upper part of the molding machine body, an outer wall of the cover, an outer wall of the cover and a peripheral wall of the molding machine body; an air chamber communicating with the air chamber through a gap in the air chamber A and a gap in the air chamber; (6) an exhaust pipe communicating with the air chamber at one end and a dust collector at the other end; (7) the dust collector. An upper punch squeak characterized by supplying air under positive pressure to the air chamber and exhausting negative pressure from the air chamber to prevent floating dust from entering around the upper punch holder and the upper punch raceway plate. Prevented rotary powder compression molding machine. 2. A rotary powder that prevents the upper punch from squeaking as claimed in claim 1, wherein a groove is provided in the part of the upper punch raceway plate that forms the air chamber that the upper punch comes into contact with, and the groove is filled with a lubricating oil-impregnated material. Compression molding machine. 3. A rotary powder compaction system that prevents the upper punch from squeaking as claimed in claim 1, wherein a lubricating oil-impregnated material is arranged in a part of the cover that forms the air chamber so as to come into contact with the head of the upper punch. Molding machine.