JPS6147578B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stamp mill, and particularly to a stamp mill suitable for pulverizing metal to produce metal powder.

Stamp mills have traditionally been used to grind various metals into fine granular powder or flaky powder.
This stamp mill performs grinding by lifting the pestle from the bottom plate and letting it fall onto the bottom plate under its own weight.
In order to use this pestle for crushing metal, it is necessary to make it extremely large (for example, 2 m long and weigh about 60 kg), and also to have a long fall distance of 10 to 30 cm under its own weight. Therefore, not only the device becomes large and the equipment cost becomes large, but also a large installation space is required. In addition, it is difficult to make the crushing part a sealed structure, which causes a lot of noise, and also requires a dust collector because the fine powder is scattered around. Furthermore, conventional stamp mills have the disadvantage that it is difficult to produce ultrafine powder, for example about 10 microns.

The present invention was made in view of the drawbacks of the prior art, and it is an object of the present invention to provide a stamp mill that is relatively small, has low noise, and is capable of producing fine granular powder or flaky powder.

The stamp mill according to the present invention includes a bottom plate, a grinding container fixed to the bottom plate, a pestle movable vertically within the grinding container so as to collide with the bottom plate, and a spring attached to the pestle in a direction toward the bottom plate. It is characterized by comprising a spring means for applying force and a vibration generator for vibrating the bottom plate.

Embodiments of the present invention will now be described in detail as illustrated in the accompanying drawings.

In FIGS. 1 and 2, a vibratory stamp mill, designated as a whole by reference numeral 1, has a bottom plate 2 and a cylindrical grinding container 3 fixed on the bottom plate 2. The bottom plate 2 has a hard metal mirror plate 4 at its center. The upper end of the grinding vessel 3 is closed with a cover 5, which holds a guide sleeve 6 in the center. The guide sleeve 6 has an inner sleeve 7 made of plastic or rubber (for example urethane) in which a punch 8 is held slidably in the vertical direction. The punch 8 has a striking part 8A made of hard metal at its lower end, and the striking part 8A strongly collides with the end plate 4 to crush metal particles located between them.

A head cover 9 is attached to the upper end of the guide sleeve 6, and a coil spring 10 is attached between the top wall of the head cover 9 and the upper end of the punch 8. The coil spring 10 applies a downward spring force to the punch 8, and thus in a direction toward the bottom plate 2. Instead of the coil spring 10, other types of springs, such as leaf springs and disc springs, may be used, and furthermore, elastic substances such as rubber and sponge, air springs, etc. may be used. Also, instead of arranging the coil spring 10 above the punch 8, a tension spring or a compression spring is arranged in parallel to the side of the guide sleeve, and the spring causes the punch 8 to
Alternatively, a downward force may be applied to.

The bottom plate 2 is attached to a vibration plate 13 supported by a pedestal 12 via a spring 11, and a bolt 14 and a nut 1.
5, and a vibration generator 16 is attached to the lower surface of the vibration plate 13. The vibration generator 16 may be any device that vibrates the vibration plate 13 and the bottom plate 2 thereon at least in the vertical direction, and any known rotary or electromagnetic vibration generator may be used. In the illustrated embodiment, a rotary vibration generator 16 is used which generates vibration by rotating an eccentric weight as shown by the arrow, and vibrates the bottom plate 2 not only in the vertical direction but also in the horizontal direction in FIG. In the above embodiment, the bottom plate 2 is replaced by the vibration plate 1.
Although the bottom plate 2 and the vibration plate 13 are provided in a removable manner, the bottom plate 2 and the vibration plate 13 may have an integral structure.

Next, the crushing operation in the above device will be explained. Metal particles to be crushed are introduced into the crushing container 3 through an input port (not shown) provided in the cover 5, and the input port is closed. Next, the vibration generator 16 is activated to vibrate the bottom plate 2. Then, due to the vibration of the bottom plate 2, the pestle 8 is flipped up, and then pushed back downward by its own weight and the force of the spring 10, colliding strongly with the end plate 4 of the bottom plate 2, flipped up again, and then pushed back downward, and so on. In the end, the punch 8 itself vibrates while repeatedly colliding with the mirror plate 8. In this way, the metal particles are crushed between the punch 8 and the mirror plate 4, which repeatedly collide with each other.

What should be noted here is that the punch 8 automatically vibrates in response to the vibration of the end plate 4 and by the action of the spring 10, and while the end plate 4 is rising, the punch 8 descends and collides with it. Therefore, when the punch 8 and the end plate 4 collide, the relative speed between the two is high, and therefore a large impact force can be obtained. Moreover, the number of collisions between the punch 8 and the end plate 4 per unit time (equal to the frequency of vibration of the punch 8)
is a fraction of the frequency of the end plate 4. For example, if the frequency of the end plate is 3000/min, the number of collisions between the punch 8 and the end plate can be about 1000 times/min.
For this reason, the frequency of collisions is much higher and the crushing efficiency is higher than that of a conventional drop-type stamp mill that uses only its own weight, which has a collision frequency of about 60 times/minute. Therefore, the punch 8 can be made lightweight and the entire device can be made smaller. A further important feature is that the frequency and amplitude of the vibration of the punch 8, which governs the impact force on the metal powder, changes depending on the spring constant and preload of the spring 10, the frequency and amplitude of the vibration generator, etc. . In the production of metal powder using a conventional stamp mill, the impact force required by the punch varies depending on the type of metal, raw material particle size, shape and particle size of the resulting metal powder, etc. For example, fine powder is produced from relatively large particles. requires multiple steps, each with a different impact force. However, with conventional stamp mills, it is extremely difficult to change the impact force, so in reality, stamp mills suitable for each process are used. For this reason, there are drawbacks such as the need to have many stamp mills and the need to transfer the material crushed by one stamp mill to the next stamp mill. However, in the vibrating stamp mill shown in FIG. A wide range of conditions can be set by changing the vibration frequency and amplitude of the vibration generator, and a single device can be used for a variety of applications. It is also possible to grind up to

The metal particles put into the crushing container 3 are crushed between the pestle 8 and the end plate 4, but because the bottom plate 2 vibrates, they are constantly stirred on the bottom plate.
The whole is ground very evenly.

After grinding for a predetermined time, the outlet 17 at the lower end of the side surface of the grinding container 3 is opened while the bottom plate 2 is vibrated.
open. Then, the metal powder is caused by the vibration of the bottom plate 2.
It is automatically taken out of the crushing container 3. This completes one crushing operation.

In order to crush metals that are easily oxidized without oxidizing them, the crushing container 3 may be filled with an inert gas.

In the above embodiment, the upper end of the crushing container 3 is sealed with the cover 5, but it is not necessarily necessary to seal the top end of the crushing container 3, but a large hole may be made in the cover 5 so that the inside can be observed.

When we conducted a grinding test using the device shown in Figure 1, we found that although it was much smaller than a conventional stamp mill, it was able to produce both granular powder and flaky powder, and it was also able to produce ultra-fine powder, which was previously unobtainable. It was confirmed that it can be made.

Experimental example raw material: SUS410L Average particle size 50μ Particle content below 10μ 0.5% Vibrating stamp mill specifications: Structure is as shown in Figure 1 Weight of pestle 14.5Kg Bottom plate vibration frequency 960/min Punch frequency Approx. 600/min Operating time :24 hour pulverized product: Average particle size 13μ Particle content below 10μ 31% The examples shown in Figures 1 and 2 are examples in which one pestle is used in one crushing container on one bottom plate. However, the present invention is not limited to this, and the number of crushing containers and pestles can be increased or decreased as appropriate. In FIG. 3, two crushing containers 30 are mounted on one vibrating plate 130, and a plurality of punches 80 are arranged in each crushing container.
This embodiment has the advantage of significantly increasing production.

The present invention provides the following advantages over conventional stamp mills.

(b) Compared to conventional stamp mills, it is extremely compact, requires less installation space, and has low equipment costs.

(b) No installation foundation work is required and it can be made mobile.

(c) It is possible to extremely efficiently produce ultrafine powder of metals (SUS, etc.) that are difficult to produce using conventional stamp mills.

(d) Since the entire device is small, soundproofing is easy.

(e) Since the vibration of the device is absorbed by the spring, no external vibration is generated.

(F) By selecting the spring and setting the conditions of the vibration generator, the grinding conditions can be changed over a wide range, and flaky powders and granular powders of various metals can be produced.

(g) Since it is easy to seal the crushing section, there are the following advantages. Prevents fine powder from scattering to the outside and preserves the working environment. It can prevent foreign matter from entering from outside. Suitable for grinding high purity metals. By enclosing an inert gas, it is possible to prevent metals that are easily oxidized during pulverization from being oxidized.

(H) It is easy to take out the metal powder after crushing.

(li) Maintenance is easy because the structure is simple.

(n) It is possible to grind different types of metals by replacing the grinding container, and it is also suitable for small-scale grinding.

The above explanation is for the case where the vibrating stamp mill of the present invention is applied to grinding metal powder.
The present invention is not limited to this, and may be applied to the crushing of other substances.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of one embodiment of the present invention, and FIG.
The figure is a view taken along the line A--A in FIG. 1, and FIG. 3 is a horizontal sectional view of another embodiment different from the above. 2... Bottom plate, 3... Grinding container, 4... Mirror plate, 6
... Guide sleeve, 8 ... Pestle, 10 ... Coil spring, 11 ... Spring, 13 ... Vibration plate, 16
...Vibration generator.

Claims (1)

[Claims] 1 a bottom plate, a crushing container fixed to the bottom plate, a pestle movable vertically within the crushing container so as to collide with the bottom plate, and a spring means for applying a spring force to the pestle in a direction toward the bottom plate. and a vibration generator that vibrates the bottom plate.