Improvements in Boller-tube Scrapers.
Year: 1891

page_text: ate of Application, 21st Mar., 1891.
Complete Specification Left, 20th Nov., 1891-Accepted, 24th Dec., 1891
PROVISIONAL SPECIFICATION
Improvements in Boller-tube Scrapers.
I, OSWALD BORCHARDT, 19 Bahnhof Strasse, of Königs-Wusterhausen, in the
Kingdom of Prussia, Germany, Manufacturer do hereby declare. the nature of this
invention to be as follows:-
The object of this invention is to construct a scraper for boiler-tubes, which
permits an easy entrance. into the tube, without having to close the scraping-jaws.
by hand, as is the case in similar devices, and which above all works with increased*
pressure in its back-motion. For this purpose I combine two double-armed spring-
levers carrying on their ends sector-shaped scrapers and being mounted on the
spindle in such a manner, so as to allow a slight vertical swivelling of the same.
The hinder ends are influenced by a spring tending to force the same against
the tube.
In order that my invention may be well understood, I refer to the accompanying.
"drawing, in which similar letters denote similar parts throughout the different views
and in which :-
:-
Figs. 1 & 2 are elevations of the apparatus in its working position,
Fig. 3 is a plan of the double-armed spring-levers,
Fig. 4 is a cross-section drawn on the line of Fig. 1.
a a are the arms of the double-spring-levers carrying at their ends the sector-
shaped scrapers s s¹, which may have merely a bevelled cutting edge or may also.
have teeth filed out similar to those of a saw. In the fulcrum of these levers, they
are loosely bolted to the spindlet by the bolt or pin The springs ff are also
mounted on the spindle and press against the inner surface of the sector-
scrapers s¹ s¹.
3.
The scraper, when at rest, will have such a position, that the ends s¹s are wide
apart, and the front scrapers ss have closed upon each other. The entrance into
the tube therefore is a very easy one. While pushing the apparatus right in, the
hinder scrapers will follow the width of the tube and open out at the front. The
elastic pliability of the complete device will aid to overcome any resistance that
will come in the way of the cutting edges of the scrapers.
In such moments the scraper-arm, knocking against a hard scale, will bend out
and shorten in its length, while the opposite scraper-arms stretch out, thus aiding
the first and the spindle moves aside out of the centre-line of the tube, as will, be
understood by a glance at Fig. 2.
By the elastic force of the springs ff, the hinder scrapers s's will have the
greater power, while the front-scrapers ss will merely be actuated by the elastic
energy of the lever-arms a a' themselves. Therefore, while being driven forward,
the scraper will cleanse the tube merely preliminary, but when moving back the.
cleansing will be a thorough one. Many and long trials have proved the superiority
of my boiler-tube scraper in comparison to all other scrapers known until this day.
Dated this 19th day of March 1891.
OSWALD PORCHARDT
COMPLETE SPECIFICATION.
Improvements in Boiler-tube Scrapers.
I, OSWALD BORCHARDT of Königs-Wusterhausen, in the Kingdom of Prussia,
Germany Manufacturer do hereby declare the nature of this invention and in
[Price 6d.].
#

page_text: what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The object of this invention is to construct a scraper for boiler-tubes, which
permits an easy entrance into the tube, without having to close the-scraping-jaws
by hand, as is the case in similar devices, and which above all works with increased
pressure in its back-motion.
For this purpose I combine two double-armed spring-levers carrying on their
ends sector-shaped scrapers and being mounted on the spindle in such a manner, so
as to allow a slight vertical swivelling of the same. The hinder ends are influenced
by a spring tending to force the same against the tube.
In order that my invention may be well understood, I refer to the drawing sent
in with Provisional Specification, in which similar letters denote similar parts.
throughout the different views, and in which:
Figs. 1 & 2 are elevations of the apparatus in its working position,
Fig. 3 is a plan of. the double-armed spring-levers,
Fig. 4 is a cross-section drawn on the line - of Fig. 1.
a a are the arms of the double-spring levers carrying at their ends the sector-
shaped scrapers, which may have merely a bevelled cutting edge or may also
have teeth filed out similar to those of a saw.
are loosely bolted to the spindlet by the bolt
mounted on the spindle t and press against
scrapers s¹ s'.
In the fulcrum of these levers, they
or pin .. The springs are also
the inner surface of the sector-
The scraper, when at rest, will have such a position, that the ends ¹s are wide
apart, and the front scrapers ss have closed upon each other. The entrance. into
the tube therefore is a very easy one. While pushing the apparatus right in, the
hinder scrapers will follow the width of the tube and open out at the front. . The
elastic pliability of the complete device will aid to overcome any resistance that
will come in the way of the cutting edges of the scrapers..
In such moments the scraper-arm, knocking against a hard scale, will bend out.
and shorten in its length, while the opposite scraper-arms stretch out, thus aiding
the first and the spindle moves aside. out of the centre-line, of the tube, as will be
understood by a glance at Fig. 2.
8
By the elastic force of the springs ff, the hinder scrapers s¹s will have the
greater power, while the front-scrapers will merely be actuated by the elastic
energy of the lever-arms a a¹ themselves. Therefore, while being driven forward,
the scraper will cleanse the tube merely preliminary, but when moving back the
cleansing will be a thorough one. Many and long trials have proved the superiority
of my boiler-tube scraper in comparison to all other scrapers known until this day.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :
1. The double-armed spring-levers a a', fixed to rod t, the opposite ends of said
levers being freely movable toward and from each other and carrying or forming
the fore-scrapers ss and the aft-scrapers s¹¹ respectively, for the purpose herein-
before described.
2. The double-armed spring-levers a a', fixed to rod t, the opposite ends of said
levers being freely movable toward and from each other and carrying or forming
the free-scrapers ss and the aft-scrapers s¹¹ respectively, in combination with
springs fixed to rod t and tending to drive apart the aft-scrapers 81 s,
substantially as hereinbefore described and shown in the drawing.
1 1001
OSWALD
BORCHARDT.
By Robert Deissler,
Agent for the Applicant.