Improvements in Thrashing Machines.
Year: 1891

page_text: Date of Application, 19th Sept., 1891
Complete Specification Left. 21st May, 1892-Accepted, 9th July, 1892
PROVISIONAL SPECIFICATION.
Improvements in Thrashing Machines.
I JAMES MARSHALL of the firm of Marshall Sons and Company Limited of
Britannia Iron Works, Gainsborough in the County of Lincoln, Engineers, do
hereby declare the nature of this invention to be as follows:-
The object of my invention is to arrange or construct the shaking and riddling
surfaces in thrashing machines so as to ensure a separation more perfect than
hitherto of the grain from the straw and the cavings when thrashing large quantities
in tropical climates.
It is found in practice that the caving riddle is often not able to perform its
work properly, especially if the straw breaks up very much as is especially the case
in hot countries because the short straw frequently becomes laid so thickly on this
riddle that the grain bas not time to find its way through the said riddle during
the passage of the short straw over the riddle and thus grain is left in the short
straw.
In order to secure a better separation of the grain from the short straw I reduce
the work which has to be done by the caving riddle by putting an additional
separating apparatus under the straw shakers and above the caving riddle. This
additional separating apparatus I by preference combine with the upper shoe, but
it may be combined with the lower shoe or be made to work from the shakers or by
separate mechanism.
In this new construction of machine the grain and short straw passing through
the concave falls on to the riddling shoe and passes on to the caving riddle but the
short straw and grain passing through the straw shakers is led on to the aforesaid
additional separating apparatus, over which a quantity of short straw passes out of
the machine, whilst only a small portion of it along with ears and grain pass
through it and is led on to the before named caving riddle, the additional separating
apparatus taking away a large quantity of the short straw, consequently the work
left for the caving riddle is materially reduced and thus the grain is effectually
separated from the cavings.
Dated this 10th day of September 1891.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Thrashing Machines.
I JAMES MARSHALL of the firm of Marshall Sons & Company Limited of
Britannia Iron Works Gainsborough in the County of Lincoln Engineers 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 :-
The object of my invention is to arrange, or construct, the shaking and riddling
surfaces, or devices, in thrashing machines, so as to ensure a more perfect separa-
tion than hitherto of the grain from the straw and cavings when thrashing large
quantities in tropical climates.
It is found, in practice, that the ordinary caving riddle, in thrashing machines as
hitherto constructed, is often not able to perform its work properly especially if the
straw breaks up very much, as is the case in hot countries, because the short straws,
or cavings, received from the concave, and from the straw shakers, are frequently
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page_text: so thick on this riddle that the grain has not time to find its way through the said
short straws, or cavings, and the riddle during the passage of the said short straws
or cavings over the riddle; and thus a portion of grain is left in the short straw,
or cavings,, when they are discharged from the machine.
In order to secure a better separation of the grain from the short straw, or
cavings, I reduce the work which has to be done by the caving riddle by putting
an additional separating apparatus (constituting a second caving riddle) under the
straw shakers and above the ordinary caving riddle. This additional separating
apparatus, or second caving riddle, I, by preference, combine, and operate, with the
upper shoe but it may be combined and operated with the lower shoe, or be worked
from the shakers, or by separate mechanism.
The accompanying drawing represents so much of a thrashing machine as is.
necessary to illustrate an arrangement according to my invention in which the
additional separating apparatus, or second caving riddle, is shewn as being connected.
and operated with the upper shoe.
Figure 1 is a vertical section and Figure 2 is a horizontal section.on the line 1-2
in Figure 1.
A, represents the ordinary caving riddle. B, the additional separating
apparatus, or second caving riddle. C shews one of the shakers, and D. is the
upper shoe; E being the lower shoe. Fis the fan or blower and G is the concave
behind the thrashing drum.
1
In this new construction of machine the grain, and short straw, or cavings,
passing through the concave G, fall on to the riddling shoe D and pass on to the
ordinary caving riddle A as heretofore, but the short straw and grain, passing
through the straw shakers (C), are led on to the additional separating apparatus,
or second caving riddle, B, over which a quantity of short straw passes out of the
machine whilst only a small portion of it with the grain pass through the said
riddle B and are led, by the underneath board H, on to the ordinary caving.
riddle A, the additional separating apparatus, or second caving riddle, taking.
away a large quantity of the short straw so that the work left for the ordinary
caving riddle A to do, is materially reduced, and thus the grain is effectually
separated from the cavings.
1
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is :-
an
In thrashing machines, a dressing apparatus forming part thereof and having
additional separating apparatus, or second caving riddle, combined therewith;
substantially as,. and for the purpose; herein before described.
Dated this 21st day of May 1892.
J. H. JOHNSON & Co.,
Agents.