Improvements in Mechanism for Cleaning Boiler Tubes and the like.
Year: 1898

page_text: Date of Application, 20th Dec., 1898-Accepted, 25th Feb., 1899
COMPLETE SPECIFICATION.
Improvements in Mechanism for Cleaning Boiler Tubes and the like.
I, EDWARD FERRIS GWYNN, of 139, South Main Street, Delaware, Ohio, U.S.A.,
Manufacturer, 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:-
My invention relates to the improvement of mechanism for cleaning boiler
tubes and the objects of my invention are to provide an improved mechanism of
this class of superior construction and arrangement of parts whereby scale and
other deposits within boiler tubes may be readily and effectively removed; to
provide in conjunction therewith improved scraping devices of superior form and
of such construction as to admit of their being readily introduced into the
mouths of the boiler tubes without the aid of guides and without engagement
with the ends of said tubes; to provide improved means for supporting and
adjusting the scraper carrying chains and to produce other improvements, the
details of construction of which will be more fully pointed out hereinafter.
These objects I accomplish in the manner illustrated in the accompanying
drawings, in which—
Fig. 1 is a longitudinal section of a tubular boiler showing my improved
cleaning device in connection therewith. Fig. 2 is a plan view of the forward
sprocket carrying shaft and its supports. Fig. 3 is a detail view in elevation of
one of the sprocket wheels showing a portion of the scraper carrying chain
thereon. Fig. 4 is a detail view in elevation of the forward shaft supports.
Fig. 4 is a detail view of the lower end portion of a supporting bar which I
employ in the manner hereinafter described. Fig. 5 is a detail view in elevation
of the rear or inner sprocket wheel supporting arm. Fig. 6 is an end view of
the latter. Fig. 7 is à longitudinal section on line y y of the same. Fig. 8 is
a similar sectional view with a portion of said arm removed. Fig. 9 is a view in
elevation of a recessed disk which I employ in the construction of said support-
ing arm. Fig. 10 is a detail view in elevation of one of my improved scrapers.
Fig. 11 is a central longitudinal section of the same on line thereof and
Fig. 12 is a detail view in perspective of the scraper arm carrying block or
swivel.
Similar numerals refer similar parts throughout the several views.
In order to facilitate the explanation of the construction and arrangement
of the parts of my improved mechanism, I will describe the same in the positions
which they occupy with reference to the boiler when said mechanism is in use
for cleaning.
1 represents a tubular boiler of ordinary construction and 2 represents the
parallel tubes thereof. represents the masonry or housing which encloses the
bciler in the usual manner and 4 represents the doorway thereof. To the frame
of the door 4 or as indicated in the drawing, to the fixed hinge pieces 5 thereon
which are arranged on opposite sides of the doorway and near the upper and
lower portions thereof, I secure outwardly projecting brackets 6. Arranged on
opposite sides of the doorway are vertical bars 7 which are secured to the

page_text: brackets 6, these bars being provided, as indicated more clearly in Fig. 4 of
the drawing, with central vertical slots or mortises 8. Projecting from the
upper end portion of each of the bars 7 is a short nut holding arm 9, these
nuts supporting vertical screw rods 10 which pass therethrough and have a
threaded engagement therewith.
11 represent vertical screw rods or standards, the lower ends of which are
seated in suitable floor blocks or socket pieces 12 at points in front of the boiler
housing and opposite the bars 7. 13 represent parallel shaft supporting bars
which extend between and are adjustably connected with said bars 7 and said
screw standards 11. These bars 13, which are inclined in the direction of the
boiler tubes, have their outer and higher ends supported in nuts 14 on the screw
standards 11, while their inner ends are hooked into engagement with hook
of the bars 7
bolts 15, the stems of which pass through the slotted openings
and which are clamped in connection with the latter through the medium of
nuts 16. The inner end portions of the bars 13 also bear upon the projecting
portions of adjusting nuts 17 on the screw rods 10. The bars 13 are provided
with longitudinal slots through which pass the clamping bolts 18 of shaft box-
ings 19, these boxings being thus adjustably supported on the bars 13, as shown.
The lower plates of the boxings 19 are provided beneath the same as indicated
more clearly in Fig. 4 of the drawings, with nuts 20, through which pass and
with which engage the threads of screw rods 21, the outer ends of the latter
having journal bearings in brackets 22, which depend from the outer portions
of the bars 13. At their outer ends each of the screw rods 21 carries a hand
wheel 23.
24 represents a transverse shaft, the end portions of which are journaled in
the boxings 19 on the bars 13. Upon the shaft 24 is mounted an operating
sprocket wheel 25 and keyed upon said shaft or otherwise adjustably supported
thereon are smaller sprocket wheels 26. In Fig. 3 of the drawing I have shown
one of the sprocket wheels 26 in detail and as indicated in said view, said wheel
is provided with a peripheral pocket or recess 26", the purpose of which will be
set forth hereinafter.
Extending from the rear or inner head plate 27 of the boiler and detachably
connected therewith in the manner hereinafter described, is a shaft or spindle
holding arm 28. The construction of this arm is shown more clearly in Figs. 5,
6, 7 and 8 of the drawings and is as follows: Extending outwardly through the
desired one of the openings 29 of the rear head plate is a bolt or threaded
rod 30, the inner end or head of which engages, as shown in Fig. 8, with a
socket in a cross bar 31 which bridges the inner side of the opening 29. On
the outer side of said opening 29 and bearing against the head plate about said
opening, I employ a metallic disk 32, the latter being provided with a radial
recess extending through its periphery to its center to receive the threaded rod
or bolt 30. On the outer side of the disk 32 I employ a clamping nut 33 which
serves to hold the disk 32 and cross bar 31 in close engagement with the head
plate. The screw rod 30 is surrounded, as indicated more clearly in Fig. 7 of
the drawings, with a tubular casing 34, the inner end of which abuts against
the disk 32 and the outer end portion of which has secured therein and extending
therethrough a transverse shaft 35, the latter having spindle ends 36. As indi-
cated, the central threaded rod or bolt 30 passes through the cross shaft 35 and
is provided on its outer end with a clamping nut 37 which is adapted to he
tightened against said cross shaft. Upon the desired one of the spindle ends
of the cross shaft, are adapted to be detachably journaled a sprocket wheel 38
which corresponds in form and construction with the sprocket wheels 26.
One of the sprocket wheels 26 is adapted to be connected with one of the rear
sprocket wheels 38 by an endless scraper carrying chain 39 which is formed
of detachable links. This chain 39 is intersected by and carries at proper inter-
vals scraping devices 40, the construction of these scraping devices being indi-
cated more clearly in Figs. 10 and 11 of the drawing, and being described as

page_text: follows: The body of each of the scraping devices consists, as shown, of a rod
or pin 41, the forward portion of which is reduced in size, resulting in the pro-
duction of a shoulder 42. The larger portion of the body 41 is provided with
threads 43, while the rear end portion of the same is formed with an enlarge-
ment 44, in which is produced a link receiving recess 45 with which is adapted
to engage one of the links 46 of the chain 39. Upon the smaller portion of the
pin or body 41 is rotatably mounted a swivel or scraper carrying block 47, while
screwed upon the threads 43 is a spreader nut 48 of the substantially truncated
cone shape shown. Pinned to the body 41 between the block 47 and shoulder 42
is a collar 49. 50 represent the scraper fingers, which as indicated in the draw-
ing, have their forward ends hooked into engagement with sockets or recesses 47ª
formed in the forward end of the block 47. From this block the fingers 50
extend rearward and outward, the extent of their outward inclination being
governed by the position of the spreader nut 48 on the pin 41. The outer or
rear end of each of the scraping arms or fingers 50 is curved outwardly as indi-
cated at 51, said outwardly curved portion forming a seat or receptacle for the
body of a scraping nail 52 which is riveted therein. As indicated at 53, these
scraping nails have their outer end portions upturned and sharpened and the
raised side walls of said nails, which are indicated at 54, are inclined downward
and forward to the body of the nail from said outer scraping edge.
In front of the forward ends of the fingers 50 and bearing against the heads
of the latter, I provide a washer 55 which is spring pressed against said finger
heads through the medium of a spring washer 56 which also surrounds the
pir 41. The forward end portion of the pin 41 is threaded to receive a nift 57
which is adapted to bear against the spring 56. As indicated in the drawing,
the nut 57 is formed with a yoke or link shaped projection 57" with which is
adapted to engage the next adjoining link 46 of the chain 39.
In utilizing the above described mechanism, the endless chain 39 is, as indi-
cated in Fig. 1 of the drawings, made to pass from front to rear through one of
the boiler tubes 2 over the sprocket wheel 38 and back through another of the
tubes 2 and over one of the sprocket wheels 26. The sprocket wheel recesses 26ª
are adapted to receive the scrapers as the chain travels over the wheel. A travel-
ing motion of the endless chain through the tubes and a consequent scraping
action of the finger nails against the scale or material with which the tubes
are encrusted, is attained through the rotary motion of the shaft 24 which is
preferably imparted from an engine located at a convenient distance therefrom.
It is obvious that in inserting the chain and in the first trips thereof through
the tubes, a desirable reduction in the flare or outward incline of the scraping
fingers is attained by turning the spreader nut 48 to the outer or rear end of
the threaded portion of the pin 41, but as the scale or other material contained
in the tubes is scraped away and carried off, it will be seen that the effectiveness
of the scraping fingers may be increased by turning said spreader nut forward.
It will be observed that loosening the nut 15 and turning the nuts 14 and 17
on the standards 10 and 11, any desirable vertical adjustment of the main shaft
supports may be attained, thus admitting of the parts being supported in the
proper positions for running the chain through other tubes. It will also be
seen that a lateral adjustment of the cleaning chain may be attained by moving
the wheel 26 on which said chain is running, laterally on the shaft 24. It will
be observed that by turning the hand wheel 23 and rotating the screw rod 21,
the shaft bearings may be moved either forward or backward to increase or
decrease the tension of the chain. By forming the spindle 36 on each end of
the cross shaft 35, it will be seen that the sprocket 38 may, when change of
location is desired, be moved from one of said spindles to the other, thus obviat-
ing the necessity of moving the arm 28 at each movement or change in position
of the chain. Owing to the fact that I have formed the curved scraping nails 52
with the inclined side walls, it will be seen that no shoulder or offset is pre-
sented at the outer end of the scraper nail which might tend to engage with the

page_text: end of the tube in the insertion of the chain therethrough, thus admitting of
such insertion and free passage of said chain through the tube without the
necessity of employing a guide extension of the tube, or any other known means
for the insertion. I preferably form the scraping nails of tool steel in order
to increase the durability and effectiveness of the same, but in case the same
should become worn, it is evident that new nails may be readily riveted to the
fingers. It will also be observed that the substantially scoop shape which I
have imparted to the scraping nails herein shown, greatly assists in the engage-
ment with and removal of the scale.
Although my improved boiler cleaning mechanism as herein described, is
particularly adapted for use in removing the scale from the interior of water
tube boilers, it is also evident that the same mechanism may be employed for
cleaning deposits from steam, heat, or smoke tubes.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
consider novel and desire to claim is:-
1. In a tubular boiler cleaning mechanism, the combination with an endless
chain adapted to pass through adjacent boiler tubes, and scraping devices
arranged at intervals in said chain, a rotatable sprocket wheel mounted in rear
of the boiler tubes over which said chain passes, screw rods 10 and 11 supported
in front of the boiler tubes, bars 13 connecting said screw rods and vertically
adjustable thereon, a transverse operating shaft journaled on said bars 13 and
one or more sprocket wheels 26 adjustably supported on said shaft, said front
and rear sprocket wheels having peripheral recesses to receive the scrapers on
the chain which passes over said wheels, substantially as and for the purpose
specified.
2. In a tubular boiler cleaning mechanism, the combination with an endless
chain carrying scrapers at intervals thereon and adapted to pass through adja-
cent tubes of a boiler, of a front and rear transverse sprocket carrying shaft
over the sprocket wheels of which said chain passes, vertically adjustable
bars 13, boxings for the support of the forward sprocket carrying shaft, said
boxings being longitudinally adjustable on said bars 13, substantially as and
for the purpose specified.
3. In a boiler tube cleaning mechanism, the combination with a tubular
boiler, a transverse adjustable shaft in front of said boiler and one or more
sprocket wheels adjustably mounted thereon, of an arm 28 detachably con-
nected with the inner end of said boiler, a transverse shaft 35 secured in said
arm, a spindle on each end of said shaft, and a sprocket wheel adapted to be
mounted on either of said spindles, of an endless chain running over said front
and rear sprocket wheels and having scraping devices at intervals thereon, sub-
stantially as and for the purpose specified.
4. In a boiler tube cleaning mechanism, the combination with an endless
chain and means for imparting a traveling motion of the same through boiler
tubes, of scraping devices arranged at intervals on said chain, each of said scrap-
ing devices consisting of a body, scraping fingers projecting therefrom and scoop
shaped scraping nails connected with said fingers, substantially as and for the
purpose specified.
5. In a boiler tube cleaning mechanism, the combination with an endless chain
and means for imparting a traveling motion of the same through boiler tubes,
of scraping devices arranged at intervals on said chain, each of said scraping
devices consisting of a body portion having a partially threaded periphery, a
block rotatably mounted thereon, finger sockets in said block, scraping fingers
detachably connected with said block sockets, substantially scoop shaped scraping
nails secured to said fingers and means for adjusting the outward incline of
said fingers from the body, substantially as and for the purpose specified.
6. In a boiler tube cleaning mechanism, the combination with an endless chain

page_text: and means for imparting a traveling motion of the same through boiler tubes,
of scraping devices arranged at intervals on said chain, each of said scraping
devices consisting of a body portion having a partially threaded periphery, a
block rotatably mounted thereon, finger sockets in said block, scraping fingers
detachably connected with said block sockets, a spring actuated washer bearing
against said finger heads and a spreader nut on said body, substantially as and
for the purpose specified.
Dated this 19th day of December 1898.
H. D. FITZPATRICK,
100, Wellington Street, Glasgow, Agent.