An Improvement in Boby Screens.
Year: 1898

page_text: Date of Application, 4th June, 1898-Accepted, 6th Aug., 1898
An Improvement in Boby Screens.
I, CHARLES EDWARD MUMFORD, of Lavenham Hill, Lavenham, Suffolk, Engineer,
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..
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6
Certain reciprocating screens for separating thick from thin grains or seeds
known as Boby screens are described in a Specification No 1134 of 1867 as
consisting of a number of parallel wires suthciently far apart to let the thin grains
or seeds pass through between the wires while the thicker gains or seeds are dis-
changed at the end of the screen In order to clear the spaces between the the wiles
a number of transverse rods are fixed below the screen these rods having strung
upon them washers which project through the spaces between the wires clearing
these spaces as the wires recipiocate while the washers remain stationary In
order to operate on grains or seeds of different kinds, such screens have to be
provided with different spacings of the wires As these screens are at present made
they cannot be exchanged without expenditure of considerable time and trouble
in removing a screen of one gauge and substituting one of a different gauge
My invention relates to a modification of the construction of such screens which
renders them capable of being readily removed and replaced as I shall describe
referring to the accompanying drawings
Fig 1 is a longitudinal section of the screen which is preferably made with
a step as at S or with several such steps
The other figures which are drawn to an enlarged scale are Fig 2 a part trans-
veise section at one side of the screen Fig. 3 a part longitudinal section and
Fig 4 a part plan
The wires Ware held in the transverse bars B connecting the two side bars A.
These have slots a through which pass the rods R that carry the washers C pro-
Jecting up into the spaces between the wnes W The ends of the rods R rest in
notches made in the upright limb of an angle iron N which is fixed on the
framing of the machine So far the construction is of the usual kind.
According to my present invention I make the sides F of the reciprocating
screen with grooves G on their inner faces at intervals corresponding with those
of the notches n. these grooves being of sufficient width to allow the ends of the
rods R to pass freely down them Instead of cutting these grooves in the side F
they may be formed by fixing on F plates f with the intervals G between them
When it is desired to remove a screen it is brought into such position that the
grooves G are immediately over the notches n, and then the screen with its rods K
can be lifted from between the end parts E of the frame, the ends of the rods
passing up the grooves G In like manner when it is desired to replace a screen,
the frame is put into such position that the grooves G are immediately over the
notches and then the screen can be lowered into position between the end
parts E, the rods R descending the grooves G Thus the provision of the grooves G
as described facilitates the removing and replacing of the screen, which hitherto

page_text: has been a work occupying considerable time and involving trouble, when it has
been necessary to remove, change or replace screens.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim is:-
The construction of the frame of a "Boby screen
"with grooves formed on the
inner faces of its sides, substantially as and for the purpose set forth.
Dated this 4th day of June 1898.
ABEL & IMRAY,
Agents for the Appplicant.