DE555510C - Double hammer mill - Google Patents

Description

GERMAN EMPIRE

ISSUED ON
JULY 25, 1932

REICH PATENT OFFICE

PATENT LETTERING

Vi 555510 CLASS 50c GROUP

Humboldt Deutzmotoren A. G. in Cologne-Kalk *) double hammer mill

Patented in the German Empire from May 8, 1931

There are hammer mills known in which two hammer stars in a common housing circulate and in which the ground material is fed to a grinding chamber, from which it is hit by the hammers in the second grinding chamber should be carried, provided that the discharge is not already through grids in the first chamber takes place. In these mills, the hammer stars usually run

ίο in the same direction so that the promotion of the Good things from the first to the second chamber did not take place with sufficient certainty. the prior art facilities do not even come close to utilizing the scope of both Hammer tracks output given grinding track lengths, although this is the only way to increase the performance of double hammer mills.

It has also already been suggested

when connecting a hammer mill with

ία of an attritor mill to let the grinding shafts rotate in the opposite direction so that the grist can pass from the first grinding chamber into the second chamber in a change of direction. In addition to the disadvantage of connecting two such dissimilar size reduction machines, this design also has the drawback that in the second grinding chamber the material is only guided over a relatively small part of the grinding path before it reaches the discharge opening. The previously known construction does not reveal a more or less complete utilization of the available grinding track length.

The invention now relates to the special design of double hammer mills with two parallel grinding shafts in a common housing on which the inlet is provided above the first mill which passes the material through a connecting opening in the second mill, such that both the inlet opening as well as the outlet opening or the end of the sieve web of the second Chamber are arranged as close as possible to the connecting opening and that the adjacent grinding shafts run in opposite directions circulate with movement in the middle from bottom to top. This ensures that the grist, as far as it was not previously discharged through the sieve path, over the entire length of the grinding path is performed so that within a mill from large to very fine grain is crushed can be. Compared to the simple hammer mills of the same diameter and the same width is actually an almost complete doubling of the effective area for comminution and

*) The inventor has been indicated by the patent seeker:

Hans Lücke in Cologne-Lindenthal.

a corresponding increase in performance achieved despite larger structural and operational Simplicity.

Since the new mill is provided with two completely separate grinding rooms, you can expediently make the first mill particularly suitable for the work of pre-crushing. For this purpose, they are equipped with stronger clubs and the waves are left accordingly circulate more slowly. The second mill receives what is required for fine grinding bigger. Number of clubs and also a finer grate gap or Mesh size. So while up to now a sieve device was used for the purpose of pre- and post-breaking, one obtains according to the present invention a spatially extremely compact one Grinding device, which also offers the advantage that intermediate screening is not required.

In a further embodiment of the invention, the second mill can also be used as a mill set up with free discharge. There are a wide variety of options. You can z. B. both mills provided with grids or sieves. It is also possible the first grinder should only be provided with grates or sieves, while the second grinder with uninterrupted grinding path works; after all, you can have both mills with uninterrupted Provided grinding track. The uninterrupted grinding path can be smooth or corrugated, depending on the material to be processed, be executed. The double mill with free discharge will be particularly suitable where moist and sticky goods, e.g. B. lignite or wet hard coal-be milled target. It depends entirely on the type of grist and the intended size reduction depend on how far you get the connection opening between the two mills and the free discharge at the end of the second Mill designed.

The drawing shows exemplary embodiments of the invention, namely Fig. Ι shows a mill with primary and secondary crusher. The material falls through the funnel α into the right mill and is pre-crushed there between the heavy hammers b, the baffle plate c ¹ , c ² and the grate track d. The baffle plate can be smooth or toothed. The sufficiently pre-crushed material passes through the connection opening e into the second mill, which is equipped with a larger number of flat beaters /. Here the final grinding takes place between the beaters /, the baffle plates g ' and the grate track h. In many cases it will be sufficient if both mills are equipped with the same grates or sieves and the same beaters; this also has the advantage that completely identical components are used. The mills described are housed in the common housing.

Figs. 2, 3 and 4 show several versions of the new double mill, in which the second mill is provided with a free discharge k . The figures reveal the essence of the invention without further ado and show in particular that grates m as well as uninterrupted grinding paths η, ο and finally simple sieves p, q can be used. With these mills, too, the first can be designed as a primary crusher with stronger impact tools and the like and the second as a fine crusher, if necessary. The uninterrupted grinding tracks can either be roughened, grooved or completely smooth on their surface.

Since the material thrown out by the free discharge often has the undesirable property of sticking and baking in the housing parts, a movable apron conveyor or a roller etc. can be installed in the path of this material, which catch the material being thrown away and from which it with the aid of a scraper How-g ₀ is removed.

Claims (6)

Patent claims: i. Double hammer mill, in which two parallel grinding shafts are arranged in a common housing with sieve or grinding tracks surrounding them completely or partially and on which the inlet is provided above the first mill, from _{10 (} , the material passes into the second mill through a connecting opening , characterized in that both the inlet opening and the outlet opening or the end of the sieve web of the second chamber are arranged as close as possible to the connecting opening and that the adjacent grinding shafts rotate in opposite directions - in the middle with movement directed from bottom to top. u ₀ 2. Double hammer mill according to claim i, characterized in that the upper edge of the connecting opening is offset towards the side of the first chamber relative to the lower edge. n ₅ 3. Double hammer mill according to claim i, characterized in that both mills are surrounded by sieve or grate coats and the second mill is one having lower free discharge just before the connection opening. 4. Double hammer mill after arrival claim I, characterized in that the first or the second mill or both Mills with uninterrupted grinding tracks and the second mill with a lower free discharge are provided. 5. Double hammer mill according to claim ι to 4, characterized in that toothed breaking surfaces (c, g) are arranged in each case in front of the perforated or uninterrupted grinding tracks. 6. Double hammer mill according to claim 1 to 5, characterized in that that the first mill, which works as a primary crusher, is stronger than the second Rackets and is operated at a lower speed. 1 sheet of drawings