Improvements in Apparatus for Removing Boiler Soale.
Year: 1892

page_text: Date of Application, 23rd Dec., 1892
Complete Specification Left 23rd Sept., 1893-Accepted, 11th Nov., 1893
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Removing Boiler Soale.
I, HENRI BASCHY, of 53 Pinnasberg, Hamburg, Germany, Engineer, do hereby
declare the nature of this invention to be as follows:-
Notwithstanding the various means that have been employed for the prevention
of the formation of boiler scale, entire success has been seldom attained and it is
therefore still always necessary to chip off the scale by mechanical means various
apparatus for the purpose having been proposed. Such apparatus however have
only been suitable for cleaning boiler tubes or other curved surfaces, and it has been
necessary up to the present to treat plane surfaces by hand with chisel and hammer.
Now this invention relates to apparatus for removing boiler scale from plane
surfaces, and in particular from those surfaces which are accessible only with
difficulty. Such are, more particularly, the surfaces which enclose the space
between the firebox and the shell of the boiler in marine and locomotive boilers,
the accessibility of which is rendered still more difficult by the stay-bolts which
serve to stiffen the plates.
An arrangement of apparatus according to my invention is as follows:-
A stirrup-shaped tool carrier is mounted in a frame with the tools, preferably
chisels, fixed therein said carrier being constantly pressed forward by means of one
or more springs fixed to the frame. Within the carrier is arranged a cam or series
of cams whose axle is provided at its upper end with one part of a suitable clutch,
the other part of said clutch being fixed to a spindle which is provided with a screw
thread working in a cross piece.
The frame is guided by means of a pivoted sliding plate, provided at one end with
adjusting set screws and suspended from suitable stay-bolts or other convenient
part of the boiler by means of two sheet metal strips.
The operation of this apparatus is as follows:-
The two sheet metal strips having been attached, say to two adjacent stay-bolts,
the apparatus after having been adjusted to the proper width by means of the
aforesaid set screws, is inserted into the space to be cleaned until the cross piece
bears against the stay-bolts. Then the spindle is screwed down by means of a key
or spanner; whereupon the teeth of the upper part of the clutch engage with the
teeth of the lower part, whereby the cam or series of cams is caused to rotate,
simultaneously with the advance of the apparatus, and act against the rear side of
the carrier drawing back the latter with the chisels attached thereto and at the
same time compressing the springs. In the continued movement the cam comes
opposite a slot in the carrier and the springs throw the carrier forward so causing
the chisels to strike against the boiler scale and break away the latter.
Then the next cam comes into operation, moves the knife-carrier back again and
then allows it to make a forward impulse. In this manner the surface is gradually
freed from boiler scale, as each blow of the chisels falls slightly in advance of the
preceding blow. The distance between the several blows depends directly on the
pitch of the spindle and the number of the cams, and can be arranged to suit
various conditions.
When the apparatus has completed its travel over the surface to be cleaned it is
withdrawn by backward rotation of the key or spanner and, as in this movement
the parts of the clutch separate, that part of the clutch which is fixed to the spindle,
does not drive the lower part mounted on the cam wheel and the chisels are not
actuated in this movement.
Dated this 23rd day of December 1892.
H. BASCHY,
By L. W., per F. B.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Removing Boiler Scale.
I, HENRI BASCHY, of 53 Pinnasberg, Hamburg, Germany, 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 :-
Notwithstanding the various means that have heretofore been employed for the
prevention of the formation of boiler scale, entire success has seldom been attained
and it is therefore still always necessary to chip off the scale by mechanical means
for which purpose various constructions of apparatus have been proposed. Such
apparatas however have only been suitable for cleaning boiler tubes or other curved
surfaces, and it has been necessary up to the present to treat plain surfaces by hand
with chisel and hammer.
Now this invention relates to apparatus whereby boiler scale can be removed
from plane surfaces, and in particular from those surfaces which are only accessible
with difficulty. Such are, more particularly, the surfaces which enclose the space
between the firebox and the shell of the boiler in marine and locomotive boilers,
the accessibility of which is rendered still more difficult by the stay-bolts which
serve to stiffen the plates.
In the accompanying drawings,
Fig. 1 is a side elevation, partly in section,
Fig. 2 an end elevation partly in section; and
Fig. 3 a plan partly in section, showing an arrangement of apparatus according
to my invention.
This apparatus comprises a stirrup-shaped tool carrier & mounted in a frame a
and having the tools, preferably chisels c fixed therein, the said carrier being
constantly pressed outward by means of one or more springs d fixed to the frame.
Within the tool carrier is arranged a cam wheel whose axle is provided at
its upper end with one part of a suitable coupling h, the other part of said
coupling being fixed to a spindle k which is provided with a screw thread working
in a cross piece i.
The frame a is guided by means of a sliding platen pivoted on a pin / in the
frame a and provided at one end with adjusting set screws m the said frame being
suspended from suitable stay-bolts o or other convenient part or parts of the boiler
by means of two sheet metal strips p.
The operation of this apparatus is as follows:-
The two sheet metal strips: p having been attached, say to two adjacent stay-
bolts o, the apparatus after being adjusted to the proper width by means of the
set screws m, is inserted into the space to be cleaned until the cross piece i bears
upon the uppermost stay-bolts. Then. the screw spindle is screwed down by
means of a key or spanner, whereupon the teeth of the upper part of the clutch
engage with the teeth of the lower part whereby the cam wheel f is caused to
rotate in the direction of the arrow Fig. 3, simultaneously with the advance of the
apparatus. By this means each of the cams or teeth on the cam wheel are caused
to act in succession against the rear side of the tool carrier so as to move back the
latter with the chiselsic, attached thereto and at the same time compressing the
springs d until the cam or tooth that is for the time being in operation comes
. opposite a slot g in the back of the tool carrier, whereupon the springs act to throw
the tool carrier forward to such an extent.as to cause the chisels c carried thereby
to strike against the boiler scale on the surface opposite them and thereby detach
the said scale therefrom, the same operation, being repeated as each cam or tooth
comes into action. In this manner the surface is gradually freed from boiler scale,
as each blow of the chisel falls slightly in advance of the preceding blow owing to
the advancing movement due to the operation of the screw spindle ... The distance

page_text: between the successive blows depends directly on the pitch of the screw spindle &
and the number of cams or teeth on the cam wheel f, and can be arranged to suit
various conditions.
When the apparatus has completed its travel and removed the scale in the
manner described from a surface equal in width to that of the apparatus, it is
withdrawn by backward rotation of the key or spanner and, as in this movement
the parts of the coupling separate, that part thereof which is fixed to the
spindle, does not drive the lower part connected to the cam wheel so that the
chisels c are not actuated during this movement.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. Apparatus for removing boiler scale, comprising an adjustable frame provided
with a tool carrier adapted to carry tools such as chisels and arranged to be
actuated in one direction by a cam or cams and in the opposite direction by a
spring or springs, the arrangement being such that when the frame is moved in an
end ways direction a reciprocating motion will be imparted to the tool carrier so
that the tools carried thereby will be caused to strike under the action of the
spring or springs against the boiler scale on the surface to which the apparatus is
applied and thereby detaching such scale substantially as herein described.
2. Apparatus of the kind referred to in the preceding claim in which the cam or
cams is or are driven in one direction only through a coupling from a screw spindle
by which the apparatus is caused to travel over the surface to be cleaned
substantially as herein described.
3. My improved apparatus for removing boiler scale, constructed arranged and
operating substantially as described and shown.
Dated this 23rd day of September 1893.
H. BASCHI,
By L. W., per W. C.