A New or Improved Rake or Scraper for Cleaning Boiler Tubes.
Year: 1892

page_text: Date of Application, 24th Sept., 1892
Complete Specification Left. 5th Apr.. 1893--Accepted. 13th Mav. 1893
PROVISIONAL SPECIFICATION.
A New or Improved Rake or Scraper for Cleaning Boiler Tubes.
We, SAMUEL ABRAHAM and LEWIS CRAWFORD ABRAHAM both of Cleveland,
United States of North America, now residing in Brussels, Belgium, Brush
Manufacturers, do hereby declare the nature of this invention to be as follows:-
This invention relates to an adjustable rake or scraper designed for cleaning
boiler tubes and especially for removing sediment or calcareous deposits therefrom.
It comprises essentially a sleeve or handle to the end of which is fitted a screw-
threaded central stem on which is mounted a circular boss having grooves forming
radial ribs between which are pivoted at one end levers carrying at their other
end knives or small wheels having conical teeth.
The knives or toothed wheels are so arranged that they can be moved away from
or nearer to the axis of the scraper at will, by simply turning the handle of the
apparatus in one or the other direction. By this means the scraper can be used
for cleaning tubes or pipes of different internal diameters, and furthermore whilst
cleaning a tube the diameter of the scraper can be increased in proportion as the
internal diameter of the tube becomes enlarged in consequence of the removal of
the sediment.
The levers carry knives or toothed wheels, or the levers may have knives and
toothed wheels arranged alternately.
The levers having toothed wheels are formed like a fork at their outer end, and
the wheel of each lever is fixed between the prongs of the fork by a pin upon
which it can turn freely. Instead of one wheel, two wheels may be arranged side
by side on one and the same pin.
According to one mode of carrying out our invention, the boss is fixed in place
on the end of the screw threaded stem, which latter is screwed into the handle of
the scraper.
The end of the handle in which is inserted the screw threaded stem, is
furnished with a conical sleeve or with a thick part which becomes gradually
thinner towards the end in which the screw-threaded stem is inserted. The levers
are fixed and pivoted in the grooves of the boss by means of pins passing through
the heads of the same, and the inner ends of the said levers bear against the
sleeve or conical part at the end of the handle.
At the end of the head of the levers there is a projecting part against the face
of which there presses the end of a spiral spring located in the inner part of the
groove of the boss. These springs have a constant tendency to press outwardly
the part of the head of the levers situated between the axis of the central stem
and their pivot, and thus press the side of the levers against the sleeve or conical
part of the handle. A cap maintained in place by a nut screwed on the end of
the central stem covers the top of the boss and of the head of the levers, and is
furnished with small internal cavities for the reception of the other part of the
springs, which are thus held in place in small chambers formed by the boss, the
interior of the cap, and the projecting part on the head of the levers.
When the handle is turned in the requisite direction so as to give it a screwing
movement on the screw-threaded central stem, the latter penetrates still further
into the handle, and the sleeve or conical part moves towards the boss and presses
outwardly the lower part of the levers against the action of the springs of the
boss, thus moving the knives or toothed wheels of the levers away from the axis
of the scraper and increasing the diameter of the acting portion of the scraper.
In order to diminish the diameter of the acting portion of the scraper the
handle is turned in the other direction, that is to say in the direction for unscrewing

page_text: the same from the central stem; the sleeve or conical part of the handle will then
move away from the boss, and the knives or toothed wheels of the levers will be
moved nearer to the axis of the scraper by the pressure of the springs of the
boss.
Dated this 24th day of Santambas 1000
S. ABRAHAM,
By L. W., per F. B.
L. C. ABRAHAM,
By L. W., per F. B.
COMPLETE SPECIFICATION.
A New or Improved Rake or Scraper for Cleaning Boiler Tubes.
We, SAMUEL ABRAHAM and LEWIS CRAWFORD ABRAHAM both of Cleveland,
United States of America now residing in Brussels, Belgium, Brush Manufacturers,
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 :-
This invention relates to an adjustable rake or scraper designed for cleaning
boiler tubes and especially for removing sediment or calcareous deposits therefrom.
It comprises a handle into the end of which is screwed one end of a screw
threaded central stem on the other end of which is mounted a circular boss having
grooves forming radial ribs between which are pivoted at one end levers carrying
at their other end knives or small wheels having conical or wedge-shaped teeth.
The knives or toothed wheels are so arranged that they can be moved away from
or nearer to the axis of the scraper at will by simply turning the handle of the
apparatus in one or the other direction. By this means the scraper can be used
for cleaning tubes or pipes of different internal diameters, and furthermore whilst
cleaning a tube the diameter of the scraper can be increased in proportion as the
internal diameter of the tube becomes enlarged in consequence of the removal of
the sediment.
The end of the handle in which is inserted the screw-threaded stem, is furnished
with a conical sleeve or enlarged part which becomes gradually thinner towards
the end in which the screw threaded stem is inserted. The levers are fixed and
pivoted in the grooves of the boss by means of pins passing through the heads of
the same, and the inner ends of the said levers bear against the sleeve or conical
part at the end of the handle.
A cap
At the end of the head of the levers there is a projecting part against the face
of which there presses a spring located in the inner part of the groove of the boss.
These springs have a constant tendency to press outwardly the head of the levers
situated between the axis of the central stem and their pivot, and thus press the
side of the levers against the sleeve or conical part of the handle.
maintained in place by a nut screwed on the end of the central stem covers the top
of the boss and of the heads of the levers, and is furnished with small internal
cavities for the reception of the upper part of the springs, which are thus held in
place in small chambers formed by the boss, the interior of the cap, and the
projecting part on the head of the levers.
In the accompanying drawings,
Fig. 1 is an elevation; and
Fig. 2 a vertical central section of a rake or scraper according to our invention
fitted with levers carrying knives which are simply fixed by means of screws to the
underside of the said levers;

page_text: Fig. 4 is an elevation of another modification in which the knives are secured by
means of screws in suitable grooves formed in the bottom part of the levers.
Fig. 5 is an elevation of a further modification in which the knives are secured
by means of screws in grooves in the levers toothed wheels being also provided.
A is the internally screw-threaded handle which is screwed upon the end of the
central stem a to the other end of which is fixed the circular boss b having radial
ribs forming grooves or recesses between which are arranged levers c c that are
pivoted at one end upon pins i, and carry at their other or free end knives d
(Figs. 1 2 and 4) or toothed wheels e combined with knives d (Figs. 3 and 5).
1 is the conical sleeve or enlarged part on the end of the handle A against which
the levers c c are constantly pressed by the action of small springs r which are
located in the upper portion of each of the grooves of the boss b and press against
a projecting part n of the levers c.
A cap p, maintained in place by a nuts screwed on the end of the central stem a,
covers the top of the boss band of the heads of the levers c and is furnished with
small internal recesses t t for the reception of the upper parts of the springs r,
which are thus held in place in small chambers formed by the boss b, the interior
of the cap p and the projecting part n on the head of the levers c.
The knives d at the end of the levers c are made of small steel blades or plates
which can be fixed to the underside of the levers by means of screws as seen in
Figs. 1, 23 and 34 so that they can be easily removed and replaced or the said
knives can be located in suitable grooves formed in the levers where they are fixed
by screws as seen in Figs. 4 and 5. The toothed wheels e, Figs. 3 and 5 are
located in slots or grooves formed in the levers between the knives d and are
mounted so as to be capable of turning freely upon pins c¹¹.
As will be seen the arrangement is such that when the handle A is turned in the
requisite direction to give it a screwing movement on the screw threaded central
stem a the latter will be drawn into the handle A and the sleeve or conical part
will move towards the boss band presses outwardly the lower ends of the levers c
against the action of the springs r, thus moving the knives d, or the toothed
wheels e and knives d d upon the levers, away from the axis of the scraper and
increasing the diameter of the acting portion of the scraper.
In order to diminish the diameter of the acting portion of the scraper the
handle A is turned in the other direction, that is to say in the direction for
unscrewing the same from the central stem a, the sleeve or conical part of the
handle will then move away from the boss b and the knives d, or toothed wheels e
and knives d d upon the levers c will be moved nearer to the axis of the scraper by
the pressure of the springs r.
Having now particularly described and ascertained the nature of the said inven.
tion and in what manner the same is to be performed we declare that what we
claim is :-
In a rake or scraper for cleaning boiler tubes the combination with an internally
screw threaded handle (A) having a conical sleeve or enlarged part (1) and a
boss (b) fixed on a stem (a) screwed freely into the handle (A), of levers (c)
pivoted to the boss (b) and carrying knives, or toothed wheels and knives and
springs (r) located in the boss (6) and adapted to press the levers (c) against the
conical sleeve or enlarged part (1) of the handle (A) substantially as described and
illustrated in the accompanying drawings.
Dated this 5th day of April 1893.
2
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S. ABRAHAM,
By L. W., per F. B.
L. C. ABRAHAM,
By L. W., per F. B.