An Improved Process of Cleaning Husked Coffee Beans, and Apparatus: therefor.
Year: 1897

page_text: Date of Application, 9th Apr., 1897-Accepted, 19th June, 1897
COMPLETE SPECIFICATION.
An Improved Process of Cleaning Husked Coffee Beans, and Apparatus:
therefor.
We, FRANZ SCHAAB and ADOLF VOLK, both of 7 Hegelgasse, Vienna I, in the
Empire of Austria-Hungary, Merchants, do hereby declare the nature of this.
invention, and in what manner the same is to be performed, to be particularly described:
and ascertained in and by the following statement:---
Coffee beans, such as obtained on the European markets, from which the husks.
have been removed, are frequently found to be covered with a layer of dirt of an
earthy nature which is encrusted over their intermediate husk or skin; they are
also frequently mixed with earthy or other foreign matter and consequently have an
earthy smell.
The present invention which relates to a particular process and apparatus, has for
its object not only to thoroughly and rapidly remove the said layer of dirt and other
foreign matter admixed with the coffee beans, but also to separate therefrom the
adherent thin intermediate husk or skin, and to destroy the earthy smell of said
beans.
In the following description we will first refer to the apparatus and will then, in
reference thereto, describe the method employed.
The mixing and rubbing device forming the essential feature of the apparatus is
represented in the accompanying drawing in vertical section.
This apparatus substantially comprises a stone receptacle A (Figure 1) closed at
its top by a dome-shaped cover A¹; the interior of the receptacle A is made circular
or oval shaped and is traversed by a vertical shaft B, to which a screw and stirring
arms D are fixed. The shaft, which is rotated, passes through a double-seat-valve B.
closing the receptacle A at its bottom, which valve, when opened, permits the contents
to fall upon the inclined tray or shoot F, which conveys them to the exterior of the
apparatus.
The driving shaft may be actuated, as represented, from below by means of bevel-
wheels or by belt-gear.
The valve E is operated by hand through the medium of the lever G, so that it can
be opened at will.
The process is as follows:-
The coffee beans are placed in the receptacle A and sufficient water is added to
just moisten their surface; a layer of saw dust or very minute chips of wood, or other
appropriate vegetable substances, are then placed on the top of the moistened coffee
beans and the shaft B is rotated. By the action of the screw C and the stirring
arms D, the coffee beans are intimately mixed with the sawdust or the like and are
at the same time thoroughly rubbed and cleaned by the combined action of the said
screw, the stirring arms, the walls of the receptacle, and the heat developed through
the frictional contact during the mixing operation. The dirt and other foreign matter
enters the soft woody fibres and particles which loosely surround the coffee beans.
When the latter have been thoroughly subjected to this operation, the whole product
is discharged by opening the valve E, and is passed into an appropriate apparatus of
the kind usually employed for cleaning grain, (and which does not form part of this
invention), and in which the loose surrounding mass or layer consisting of dirt, of
fibres or particles of wood, and of particles of the thin intermediate husk or skin, is
removed from the beans, which are then thoroughly clean, smooth, and free from any
earthy smell.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. An improved process of cleaning husked coffee beans, according to which the
said coffee beans are superficially moistened with water and mixed with sawdust or
minute chips of whod, whereby, through the medium of a stirring device, the dirt and
the thin intermediate husk or skin are separated from the beans, and form, together
with the sawdust or chips of wood, a mass or layer which loosely surrounds the beans,
and which is subsequently separated therefrom by means of an apparatus resembling
in its action an ordinary grain cleaning machine.
2. For carrying out the process claimed in the first claim, an apparatus, consisting
of a circular or oval shaped receptacle (A) with dome-shaped top-cover (A'), in
which receptacle rotates a vertical shaft (B) provided with a screw (C) and stirring
arms (D); the said shaft traversing a double-seat-valve (E) closing the receptacle at
its bottom, which valve, when open, discharges the contents upon an inclined tray or
shoot (F); the shaft (B) being driven from a suitable point below the inclined tray,
and the valve (E) being actuated by à lever (G) substantially as described.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, W.C., Agents for the Applicants.