JPH0251720B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to powder (including granular) as a raw material.
This article relates to a powder compression molding machine that produces molded products (so-called tablet-like products) for pharmaceuticals, foods, agricultural chemicals, electrical parts, chemicals, etc. by compressing the powder. The present invention relates to a method for removing powder adhering to a mortar hole in a powder compression molding machine for removing powder adhering to the peripheral wall of a mortar hole.

(Prior art) Generally, a powder compression molding machine has a mortar, and an upper punch and a lower punch are disposed opposite to the mortar so as to be able to freely slide up and down, and the bottom of the mortar hole is formed by the lower punch. After the powder is filled into the mortar hole and compression molded using an upper punch and a lower punch, the lower punch is raised to take out the molded product.

However, depending on the properties of the raw material powder, the powder may adhere to the peripheral wall of the mortar hole during molding, and as molding continues, the powder will grow and solidify, resulting in compression. When the molded product is taken out with a lower punch, the side band of the molded product rubs against the powder adhered to the peripheral wall, and the side band of the molded product, which is the finished product, develops dull vertical scratches and becomes inferior. It becomes a product.

In addition, due to such rubbing of the molded product, it will not come out easily from the mortar hole, and excessive force will be applied to the lower punch as it tries to rise, causing the lower punch to bend or break out, and the molded product to be damaged. Capping, lamination, cracking, etc. occur.

Particularly, this powder adhesion in the mortar hole is significant when foaming agents such as citric acid, tartaric acid, baking soda, sugar, etc. are used as raw materials.

Conventionally, the molding machine was stopped periodically to clean the inside of the mortar hole and remove unnecessary powder adhering to the peripheral wall.

(Problems to be Solved by the Invention) Even with such conventional technology, molded products can be obtained, but the molding machine must be stopped periodically, resulting in poor production efficiency. In particular, rotary powder compression molding machines intended for mass production have had the problem of extremely poor operating efficiency.

In addition, it is very difficult to remove powder that has adhered or adhered to the mortar hole, and if cleaning management is neglected, not only will it not be possible to obtain a good molded product, but the lower punch may be damaged, etc. There was a problem that caused a hindrance.

(Means for Solving the Problems) In order to solve these problems, the present invention provides a mortar for powder compression molding in which a mortar hole in a mortar is filled with powder and the powder is compressed by a lower punch and an upper punch. In the method for removing powder adhering to a hole, the diameter of the tip of the punch is formed smaller than the diameter of the mortar hole to form a compression part, and a sliding contact is provided below the compression part and has a diameter larger than that of the compression part and is slidably inserted into the mortar hole. of the mortar hole in a powder compression molding machine, characterized in that powder adhering to the peripheral wall of the mortar hole during compression molding is removed at the sliding contact portion of the lower punch by using a lower punch with a A method for removing adhered powder is provided.

In the above configuration, the lower punch may have a small diameter portion between the compression portion and the sliding contact portion, the diameter being smaller than the diameter of the compression portion.

Further, in the above configuration, the lower punch may have a diameter of the shaft portion below the sliding contact portion smaller than a diameter of the compression portion.

Furthermore, in the above configuration, the sliding contact portion of the lower punch can be shaped like a gear with a large number of notched grooves provided on its outer circumference.

Furthermore, in the above configuration, the sliding contact portion of the lower punch is
An appropriate number of spiral grooves can be provided on the outer periphery.

(effect) The above technical means works as follows.

The powder filled into the mortar hole in a fixed amount is compressed by the compression parts which are the punch tips of the upper and lower punches, and in this case, the compression part has a diameter smaller than the diameter of the mortar hole and also smaller than the diameter of the sliding part. However, the overall dimensional difference is small, and it can be compressed without any problems.

After this compression, the upper punch rises, and then the lower punch rises to push up the compressed molded product, but the sliding part located below the compression part causes the mortar hole to open each time the lower punch rises. It acts as if it scrapes the peripheral wall and scrapes off unnecessary powder adhering to the mortar hole every time compression molding is performed.

(Example) An example of the present invention will be described with reference to the drawings.
1 and 2 show one embodiment of the present invention.

Reference numeral 1 denotes a large number of dies arranged at equal intervals on the circumference of a rotary disk 9 in a rotary powder compression molding machine.

Reference numeral 2 denotes a peripheral wall portion inside the mortar hole of the mortar 1.

Reference numeral 3 denotes a lower punch main body, which is integrally formed with a compression part 4, a small diameter part 6, a sliding part 5, and a shaft part 7 in this order from the punch tip.

The relationship between the various parts of the lower punch body 3 is such that the diameter of the compressed part 4 is smaller than the diameter of the mortar hole of the mortar 1 (for example,
The small diameter portion 6 is formed to have an even smaller diameter than the compression portion 4 (for example, 0.6 mm smaller than the diameter of the mortar hole), and the sliding portion 5 is larger than the diameter of the compression portion 4 and extremely slightly smaller than the diameter of the mortar hole. (For example, from the mortar hole diameter
0.03 mm smaller), and the shaft portion 7 has the same diameter as the small diameter portion 6.

That is, in FIG. 1, the lower punch main body 3 has its sliding contact portion 5 slidably inserted into the mortar hole, and the compression portion 4, which is the tip of the punch, for compressing powder is inserted into the sliding contact portion 5. It has a slightly smaller diameter and forms the bottom of the mortar hole.

Figure 2 shows a state in which the lower punch body 3 is raised to take out the molded product (not shown) after the powder is filled into the mortar hole (not shown) and compressed by the lower punch body 3 and the upper punch 8. By sliding in the mortar hole, the sliding contact part 5 scrapes off unnecessary powder adhering to the peripheral wall part 2 of the mortar hole due to compression, and takes it out to the upper part of the mortar 1, and removes it to the upper part of the mortar 1 by means of a dust suction device 10. The removed powder is collected outside.

FIG. 3 shows another embodiment of the present invention, in which reference numeral 11 denotes a mortar disposed on the base of a single-action powder compression molding machine.

Reference numeral 12 denotes a peripheral wall portion inside the mortar hole of the mortar 11.

13 is a compression part 14, a small diameter part 16,
This is a lower punch main body in which a sliding contact portion 15 and a shaft portion 17 are integrally formed in this order.

The relationship between the parts of this lower punch body 13 is the same as that of the previous embodiment, but an appropriate number of inclined grooves 18 are provided on the outer periphery of the sliding contact part 15, and the sliding contact part 15 allows the parts to be scraped off. The unnecessary powder is dropped from the groove 18 and removed.

Note that the present invention is not limited to the above-mentioned embodiments. For example, in a molding machine in which a molded product is taken out from below the mortar, the present invention can be achieved by using the lower punch structure of the present invention as the upper punch. Similarly, powder adhering to the mortar hole can be removed.

(Effects of the Invention) As explained above, the present invention is capable of removing unnecessary powder adhering to the mortar hole every time compression molding is performed by using a lower punch that slides inside the mortar hole every time molding is performed. Therefore, there is no need for complicated cleaning management of the mortar hole, and there is no need to stop the molding machine for cleaning.
This has the effect of preventing damage to the lower punch, etc., and easily improving production efficiency.

[Brief explanation of the drawing]

The drawings show a method for removing powder adhered to a mortar hole in a powder compression molding machine according to the present invention, and
The figure is a vertical sectional view of main parts showing one embodiment of the present invention,
This figure is also a longitudinal cross-sectional view of the main part, and FIG. 3 is a longitudinal cross-sectional view of the main part showing another embodiment of the present invention. In the drawing, 1 is a die, 2 is a peripheral wall part, 3 is a lower punch body, 4 is a compression part, 5 is a sliding contact part, 6 is a small diameter part, 7
8 is a shaft, 8 is an upper punch, 9 is a rotary disk, and 10 is a dust suction device.

Claims (1)

[Claims] 1. In a method for removing adhering powder from a mortar hole in powder compression molding, in which powder is filled into the mortar hole of a mortar and compressed using a lower punch and an upper punch, the diameter of the punch tip is formed smaller than the diameter of the mortar hole and used as a compression part. By using a lower punch that has a sliding contact part formed below that has a larger diameter than the compression part and is slidably inserted into the mortar hole, it adheres to the peripheral wall in the mortar hole during compression molding. A method for removing powder adhering to a mortar hole in a powder compression molding machine, characterized in that powder is removed at a sliding contact portion of a lower punch.