JP3341447B2 - Powder compression molding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder compression molding in which a powder, which is a raw material of a powder compression molded product (hereinafter referred to as a molded product), is filled in a die and the powder is compressed with a punch to form the molded product. The present invention relates to an apparatus (hereinafter, referred to as a molding apparatus), and particularly to a molding apparatus for making a thickness of a molded body constant.

[0002]

2. Description of the Related Art A conventional molding apparatus will be described with reference to FIG. 2 which is a schematic view of a cross-section developed by punches arranged in a circle in order to show an operation state of a rotary type as an example. However, some punches and the like that are not necessary for description are omitted.

In the rotary molding apparatus, the rotary plate 1, the upper punch holding plate 2, and the lower punch holding plate 3 are integrally rotated about a central axis (not shown). A large number (four in the figure) of stepped holes 1a are provided at equal intervals on a certain circumferential surface of the rotary plate 1, and the upper punch holding plate 2 and the lower punch holding plate 3 at the same positions as the step holes 1a. And the same number of through holes 2a, 3 corresponding to the stepped holes 1a.
a is provided. A die 5 having a die hole 5a is fitted into the stepped hole 1a, an upper punch holder 6a is inserted into the through hole 2a of the upper punch holding plate 2, and a lower punch holder 7a is inserted into the through hole 3a of the lower punch holding plate 3. Are slidably inserted respectively. Then, the upper punch 6 and the lower punch 7 move up and down to compress the powder 8 filled in the die hole 5a to form the molded body 9.

The upper punch 6 includes, for example, an upper punch holder 6a for slidably inserting into the through hole 2a of the upper punch holding plate 2,
And a punch portion 6b for insertion into the die hole 5a.
The upper punch 6 can be moved rightward in the figure at a height determined by an upper punch guide rail (not shown) disposed above the upper punch holding plate 2. .

The lower punch 7 has a lower punch holder 7 like the upper punch 6.
a and a punch 7b. The lower punch 7 moves rightward in the figure at a predetermined height by moving on surfaces such as the lower punch guide rail 10 and the weight rail 11 installed below the lower punch holding plate 3. Can be.

On the upper surface of the rotary disk 1, a feed shoe 16 for supplying the powder 8 as a raw material of the compact 9 little by little to the die hole 5a, a scraper 12 for removing excess raw material, and a compacted compact 9 are provided. Plate 1 for scraping off
3 are arranged.

Below the lower punch holding plate 3, a weight rail 11 for raising the lower punch 7 in order to keep the amount of the powder 8 filled inside the die hole 5 a constant, and filling the inside of the die hole 5 a. The lower punch 14 for raising the lower punch 7 further to compress the powder 8, and the lower punch 7 between the weight rail 11 and the lower compression roller 14 and between the lower compression roller 14 and the weight rail 11. Lower punch 7 while moving to the right smoothly
Is provided with a lower punch guide rail 10 for vertically moving the lower punch.

Above the upper punch holding plate 2, an upper compression roller 15 for lowering the upper punch 6 for compressing a certain amount of powder 8 inside the die hole 5 a corresponds to the lower compression roller 14. Installed.

[0009] Using the molding apparatus having such a configuration, the molded body 9 is formed.
The process of molding the will be described. In the position shown in FIG. 2A, a molding chamber is formed in the die 5 from the die hole 5a and the bottom, which is the upper end of the lower punch 7. The powder 8 as the material of the molded body 9 is
While being supplied to the feed shoe 16 on the upper surface of the turntable 1, it is charged into a molding chamber formed inside the die hole 5a.

In the position shown in FIG. 2 (b), the powder 8 filled in the die hole 5a is displaced by lowering the upper punch 6 by the upper compression roller 15 and raising the lower punch 7 by the lower compression roller 14. , Compressed.

At the position shown in FIG. 2 (c), the compressed compact 9 in the die hole 5a is rotated by the lower punch 7 by the lower punch guide rail 10 and the lower punch 7 by the lower punch guide rail 10. Lifted to the top of 1. The compact 9 is scraped off by a scraping plate 13 provided on the upper part of the turntable 1 and discharged from the upper part of the turntable 1 via a chute 16 or the like.

[0012]

Generally, due to mechanical factors caused by the molding apparatus, the molding apparatus and upper and lower holders,
It is known that, when the dimensions of each part change due to thermal expansion of a punch, a compression roller, and the like, the amount of powder to be filled into a die and the compression pressure of the powder change, and the thickness of a compact changes.

However, since it is difficult to measure the total thickness of the molded body, it is necessary to reduce the molded body from several minutes to several tens of minutes.
The sample is taken about once and measured. The thickness fluctuation of the molded body is estimated from this data, and the height of the weight rail and the vertical compression / pressing roller is adjusted in order to optimize the thickness of the molded body. Therefore, there are the following problems.

1. Since the timing of measuring the thickness of the molded product is intermittent, when a dimensional defect is found, defective products have already been produced to some extent.

2. When the state of the molding apparatus is unstable, for example, immediately after starting the molding apparatus or when the punch and the mortar are expanding or contracting due to a temperature change, the thickness of the molded body may change suddenly. It is difficult to adjust the thickness of the molded body corresponding to this.

3. In order to form a molded article having a complicated shape, the flowability of the raw material in the die is not uniform, so that it is insufficient to confirm the thickness dimension of the molded article by extracting.

An object of the present invention is to solve the above-mentioned problems. A molding apparatus is provided with means for measuring the thickness of a molded body in a non-contact manner, and the thickness of the molded body is measured in total. An object of the present invention is to provide a molding apparatus capable of always keeping the thickness of a molded body constant by moving a lower compression roller of the molding apparatus up and down to control a height position.

[0018]

Therefore, in the present invention, there is provided an upper punch and a lower punch, and a die having a die through which the punches of the upper and lower punches can be inserted. Fill the powder,
The upper punch and the lower punch, a powder compression molding machine for compression-molding the powder, a lower compression roller capable of raising and lowering the compression height of the lower punch, and a thickness of the compression-molded powder compression molded body. It is characterized by comprising a measuring means for measuring by contact, and a height control device connected to the measuring means for controlling the height of the lower compression roller.

[0019]

That is, in the present invention, the thickness of the molded body is measured by the non-contact molded body thickness measuring means installed in the molding apparatus, and the lower compression roller is moved up and down based on the measurement result. Therefore, during operation of the molding apparatus, the lower compression roller moves up and down based on the adjustment amount, and maintains the thickness of the molded body constant.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. However, the same parts as those in the above-described conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 1 is a schematic view of a molding apparatus according to the present invention. A molding machine 20 is one of the molding machines shown in the prior art, in which the lower compression roller 14 can be moved up and down. The molding machine 20 measures the thickness of the molded body 9 in a non-contact manner, for example, a measuring unit 21 such as an image processing device or a laser measuring machine, and a height control device 22 of the lower compression roller 14. For example, a driving means 23 such as a motor for raising and lowering the compression roller 14 is provided.

The measuring means 21 is installed near the chute 16 from which the molded body 9 is discharged, and measures the thickness T of all the molded bodies 9 passing through the chute 16 in a non-contact manner. The measurement signal of the thickness T is sent to the control device 22. The control device 22 calculates a difference from a set value of the thickness and a transition of the difference based on the measurement signal of the thickness T. Then, by controlling the rotation of the driving means 23, the driving means 23 rotates the rotating body 24 formed of a female screw, and moves the supporting rod 25 formed of a male screw threadedly fitted to the rotating body 24 up and down. The height of the lower compression roller 14 connected to 25 is adjusted.

When the molding machine 20 is operated, the molding 9 is discharged from the molding machine 20 via the chute 16 of the molding machine 20. Measuring means 21 installed near chute 16
Is used to measure the thickness T of all the compacts 9 in a non-contact manner. The measurement signal of the thickness T is sent to the control device 22. The control device 22 is connected to a driving unit 23 that raises and lowers the lower compression roller 14 based on a signal.

In the molding apparatus having such a configuration, the measuring means 21 measures the thickness T of all the molded bodies 9, and based on the measurement result, the control unit 22 calculates, for example, the set value and the thickness T of the molded body 9. A control signal is sent to the driving unit 23 based on the difference and the change tendency of the difference. The driving means 23 rotates based on a control signal from the control device 22 to move the lower compression roller 14 up and down. That is, by adjusting the distance D between the lower end of the upper punch 6 and the upper end of the lower punch 7, the thickness T of the molded body 9 can be kept constant.

The thickness T of the molded body 9 is controlled by moving the lower compression roller 14 up and down. Alternatively, the upper compression roller 15 may be moved up and down, or both the upper and lower compression rollers 14 and 15 may be moved up and down. May be. Also, the molded body 9
After the thickness T is measured, a means for eliminating the molded body 9 is provided, and defective products having the thickness T can be eliminated. Further, in order to control the filling amount of the powder 8, a device for measuring the weight of the compact 9 and controlling the height of the weight rail based on the measurement result to make the filling amount of the powder 8 constant is provided. It is also possible to combine them.

The above-mentioned powder 8 is a powder in a broad sense and includes particles and fine particles.

[0027]

As described above, in the powder compression molding apparatus according to the present invention, the thickness of the compact can be constantly measured because the non-contact type compact thickness measuring device is added to the compacting apparatus. For this reason, during molding using the molding apparatus, the thickness of the molded body can be made constant by raising and lowering the lower compression roller by feeding back in real time based on the measurement result.

Therefore, since the molding apparatus during powder molding can maintain a constant thickness of the compact, the number of defective molded articles decreases and the yield of the compact increases.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of one embodiment showing a molding apparatus according to the present invention.

FIG. 2 is a partial schematic view of a conventional powder compression molding apparatus, in particular, a cross section developed with punches arranged in a circle.

[Explanation of symbols]

 Reference Signs List 5 mortar 5a mortar hole 6 upper punch 7 lower punch 8 powder 9 powder compression molding (molded product) 14 lower compression roller 20 powder compression molding machine (molding machine) 21 measuring means 22 controller

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B30B 11/08 B22F 3/02 G01B 7/02

Claims (1)

(57) [Claims] An upper punch and a lower punch, and a die having a die hole through which the punch portions of the upper punch and the lower punch can be inserted. Powder is filled in the die hole, and the upper punch and the lower punch are filled. A powder compression molding machine for compressing and molding the powder by means of a punch, a lower compression roller capable of raising and lowering the compression height of the lower punch, and a measuring means for measuring the thickness of the compression molded powder compact in a non-contact manner And a height control device connected to the measuring means for controlling the height of the lower compression roller.