DE7202175U - Pair of grinding stones for flour mill - Google Patents

Description

Millstone pair for flour mill

The invention "relates to a pair of grinding stones for grain mills, especially small and medium-sized hand or motorized flour mills.

Investigations by the inventor have shown that when grinding grain it is important that the grist is one covers the longest possible distance between the grinding surfaces of the millstones. Only in this way can it be achieved that the individual grains of oirae 'exercise are too great Ground forces into fine flour. The exercise large forces require too much energy in small electric or hand-operated mills. Above all

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however, these great forces lead to an unfavorable one Heating of the grist.

By means of the much larger grinding stones from in large mills Common grinders will grind the grains finely without significant heating, since the grains because of the larger dimensions between the millstones inevitably have to cover a greater distance. With smaller ones and medium-sized mills for the household and for bakeries, iron the millstones with a much smaller diameter, this result can be achieved with a However, it is practically impossible to achieve a casual grinding process.

The invention is therefore based on the object of making the path of the flour material between the millstones large enough, even with a smaller millstone diameter, to be able to grind the grains into fine flour. This object is achieved according to the invention in that at least one of the millstones mincJeytens has a groove in the T'inh'i flHrTn ^ which runs in a spiral shape from Steinhers almost to the circumference flns Vif \ h ~ i ntejnes and decreases in its depth from Steinherz κ by the circumference, where the angle between ^ eflp'vr · Tb: c-ι uc ;; ·! -! <·] jer dvasplben see ti id end groove preferred

On Ή ^ s-; V'el.T ^ becomes ννττ. ·] CVit, that the individual grains, before never 1.13g of the I3 ^ re:) from the grinding surfaces emerge, a wormfiirl; Vi.cT: .i. Change 1, go back through the spiral-shaped hats. As the depth of the spiral grooves decreases from the inside to the outside, the grains always lie on both grinding surfaces, even if they become smaller as a result of the grinding process, and are further ground.

The cross section of the individual grooves can, for example triangular, trapezoidal, rectangular, semicircular, be semi-elliptisoh or dergleiohen. The two millstones can be flat, frustoconical, or domed Own hollow fleas.

An embodiment is particularly useful in which the two successive grinding surfaces at least contain a spiral groove. Depending on the size of the stone, there can also be several nested, spiral-shaped stones Grooves may be provided. If both grinding surfaces contain grooves, then the grooves which move against one another result in a so-called effect on the material to be ground.

According to a further proposal of the invention, it is also possible that the pitch of the spiral grooves decreases from the inside to the outside. Since the ineren Bere ^one oh the Zerklei "" • aeÄtsng of the grains to a certain degree relatively sohnell going on, the dwell time of the ground material in the inner area near the stone heart can, in favor of the residence time in the outer Bereiohen. the "Mahlfläohen" can be shortened somewhat.

Exemplary embodiments of the invention are explained in more detail with the aid of the figures. It shows

Figure 1 is a view of a millstone with a flat Grinding surface and a spiral groove,

FIG. 2 shows an axial section of a pair of grinding stones lying on top of one another with a flat grinding surface and, 1e of a spiral groove,

FIG. 3 shows an axial section through a pair of millstones arranged at a distance from one another and having a frustoconical Grinding surface and .1e of a spiral groove,

FIG. 4 shows a plan view of a grinding stone with a flat grinding surface and three spiral grooves fitted into one another
and

Figure 5 six different embodiments of the cross-son of the spiral-shaped ITuts.

In all figures, the same or corresponding parts are provided with the same reference numerals.

The grinding stone 10 shown in Figure 1 has a flat Mahlfläohe 12 with a central cavity, the so-called Stone heart 16, in which the through hole 14 flows out. A spiral groove with a very flat, constant spiral pitch extends from the stone heart 16 and extends almost to the circumference of the millstone

The bet the millstones 10 and 10a of the one shown in Figure 2 Mahbtein couple also have a stone heart 16 or 16a with subsequent through bores 14 and 14a, flat grinding surfaces and in, -Each grinding surface one from the stone heart outgoing spiral hat 20 or 20a. As can be seen from Figure 2, takes the triangular cross-section of the spiral grooves 20 and 20a in this embodiment from the inside out.

The same applies to the pair of grinding stones shown in FIG 30, 30a Durohgangsbohrungen I4 or. 14a? Stone hearts 16 or 16a as well as in this lall frustoconical Grinding surfaces 32 and 32a are provided. The grinding surfaces 32, 32 a each contain a spiral groove 20 or 20a with a triangular, from the inside to the outside decreasing cross-section.

The grinding stone 10 shown in FIG. 4 also has one flat grinding surface 12, a Durchgarigsbohrimg 14 and a Steinherz 16. At this execution agsforra go however three interleaved spiral grooves 22, 24 and 26 from the stone heart 16 and extend with one inside The area of the grinding surface is somewhat larger and outwards decreasing spiral slope towards the outside until close to TJmfan / 5 of the millstone 10. The spiral inclination is less than 45 ° at this point.

A larger slope is not advisable because the grist otherwise it gets to the outside too quickly and the retarding effect of the grooves is too small.

Figure 5 shows various advantageous embodiments of the groove cross-section, namely a two triangular groove cross cross-sections 40 and 42 each with an inclined flank, a three-cornered groove cross-section 44 with two inclined planks, a square groove cross section 46, a TT-fSrtni- · gen ÜTutenquersohnitt 48 and a ti'äpesförniigen Nntenquersohnitt 50

Claims (4)

Pertwrrt to sprlioh e 1. pair of grinding stones for grain mill, characterized in that at least one of the grinding stones (10) at least one from the stone heart (16) "to almost the circumference of the grinding stone running in a spiral shape, in its run from the stone heart to the circumference decreasing groove (18) in the grinding surface (12), the angle between, leather radius and the same intersecting Groove is preferably always greater than 45 °. 2. pair of grinding stones according to claim 1, characterized in that both grinding stones (1ο, 1oa; 30, 3Oa) at least contain a spiral groove (20, 20a) in the grinding surface (12} 32, 32a). 3. Mahlateinpaar according to claim 1 or 2, characterized daduroh, da8 a plurality of nested spiral-shaped Grooves (22, 24, 26) are provided. 4. pair of millstones naoh one of the preceding claims, marked daduroh, <let the slope of the spiral grooves (22, 24, 26) decrease from the inside to the outside.