Improvements in Brazing Machines and Brazing Processes.
Year: 1899

page_text: Date of Application, 30th May, 1899-Accepted, 22nd July, 1899
COMPLETE SPECIFICATION.
Improvements in Brazing Machines and Brazing Processes.
I, ALDEN AARON STEWARD, of East Clarendon, in the County of Rutland
and State of Vermont, United States of America, 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:
This invention relates to brazing machines and brazing processes and more
particularly to a machine for brazing cylindrical articles such as tubing. It has
for its object to provide a novel and improved construction of heater for fusing
the spelter or solder and for moving the article to be brazed through the heater
during such operation. It has as a further object to provide an improved con-
struction of apparatus for the application of the flux, the wiping of the fluxed
joint and the application of graphite to the same before the tube enters the
heater.
Other objects and advantages of the invention will hereinafter appear in the
following description and the novel features thereof will be particularly pointed
out in the appended claims.
In the drawings:
Fig. 1 is a vertical cross section through the heater:
Fig. 2 is a plan view of the mechanism located at one end of the heater.
Fig. 2 is a continuation of Fig. 2 illustrating the discharge of the machine.
Fig. 3 is an end elevation with parts in section of the flux applying apparatus.
Fig. 4 is a side elevation of the wiping belt.
Fig. 5 is a similar view of the graphite applying device.
Fig. 6 is a detail vertical section through the burner.
Fig. 7 is a perspective of the finger and refractory tip composing parts of the
endless carrier for supporting the article to be brazed, and
Fig. 8 is an end elevation of the discharge end of the machine illustrating
the driving means.
Like letters of reference indicate like parts throughout the several figures of
the drawings.
The letter A indicates the base or foundation of the heater and the latter A¹
the top or heat retaining shield thereof. The portion A is supported from the
base by means of the body portion A², and at opposite ends of the base suitable
rollers or sprockets B are provided. Intermediate of the top and base a parti-
tion A is arranged so as to leave a heat conducting passage A+ between the top
and said partition. This partition plate at its central portion extends upward
within the recess in the top so as to form a chamber A5 to receive the article to
be brazed. This chamber may be of any desired shape suitable for the reception
of the article to be brazed. Between the partition and the top a series of sup-
porting blocks A are arranged to carry the weight of the portion A
opening a is formed in the central portion of the partition A³ so that the products
An

page_text: of combustion may pass from the brazing chamber into the conducting
passage A, and by passing therethrough heat the outer surface of the partition.
Beneath the brazing chamber A³, a burner C or other suitable heating device
is arranged which is adapted for the reception of any suitable fuel such as air
and gas, and is provided at its upper portion with openings C which lie beneath
the joint of the tube D to be brazed. This burner is provided with a flattened
upper surface C2 and depending walls C³. These walls are surrounded at their
lower portions by an enclosing casing C closed at its lower portion. It will
thus be seen that the air and gas passing to the burner opening C will be given
a circuitous course and thus thoroughly mixed while the portion C¹ of the burner
will be cooled and prevented from warping by the contact therewith of the fuel
before ignition. The fuel in passing to the burner opening is conducted over
the upper end of the enclosing casing C and thus brought in contact with the
under surface of the burner top C³. The flames from the two openings C¹ will
merge together so as to maintain a zone of heat directly under the point to be
brazed without excessively heating the remainder of the tubular article in the
brazing chamber. The heat will pass around the article and hence through the
aperture a, into the passage A*, thus maintaining an even temperature in the
brazing chamber and protecting the same against the influence of the exterior
atmosphere.
The burner may be adjusted to and from the article to be brazed by means
of an adjustable yoke E which is supported from a base E by means of adjusting
screws E². It is obvious that this adjusting means may be altered and that in
the present form the raising or lowering of the burner will control the amount
of contact of the flame with the article brazed.
The tube or other article to be brazed is moved through the heater by means
of an endless carrier which is composed of a series of links F1 (as shown in
Figure 7) having upwardly extending fingers F2 provided at their extreme upper
ends with removable refractory tips F3 adapted to contact with and support the
articles to be brazed. These tips may be of any desired refractory material and
retained upon the finger by means of a socket F. The upper portion of the
finger is inclined at an angle to the lower part thereof so that the fingers upon
the opposite carriers will ineline toward each other and thus support the article
to be brazed without the metallic portion coming into contact with the flame
from the burner. The link F is provided with a depending lug F5 which travels
in a recess a formed in the base A of the heater so that the carriers are positively
guided in their movement and in their relation to the other parts of the apparatus.
The carriers may be driven by any suitable means, for instance sprocket teeth
arranged upon the sheaves B or at any other suitable point in the circuit of the
conveyors. The sheaves B may be suitably driven by any power mechanism for
instance such as illustrated in Fig. 8. As illustrated, each of the sheaves B is
mounted upon a spindle B¹ which at its lower portion is provided with a meshing
gear wheel B². These gears thus drive the opposite carriers and one of the
sheaves B is further provided with a bevelled gear 13 meshing with a bevelled
pinion B carried by a shaft B which may be suitably driven by any power
through the medium of a band wheel B. The heating device C may likewise be
supplied by any preferred connection, for instance an inlet gas pipe 12 which is
provided with a movable section D³ connected with the heater, the sections D²
and D3 being connected together by a collar D+ which permits the movement of
the section 13 in the vertical adjustment of the heating device. An inlet pipe D³
communicating with the pipe 13 is also provided. The work when discharged
from the machine may be delivered upon any suitable form of trough or way, for
instance, as shown at 106. The use of the refractory tips F3 protect the fingers of
the conveyors from injury due to the high heat used in brazing, and the structure
and arrangement of the endless conveyers cause them to support and carry the
tubular article to be brazed through the heater at any predetermined speed.
In order to prepare the joint for the proper adhesion of the spelter in the

page_text: brazing operation, I provide adjacent to the heater a fluxing apparatus to apply
flux to the joint and at a suitable distance therefrom a wiper to remove the
surplus flux from the joint. In order to prevent the adhesion of the spelter to
the tube upon the exterior surface adjacent to the joint, I apply dry graphite or
other suitable material by means of an apparatus to be hereinafter described
which prevents the adhesion of the spelter to the exterior of the tube where the
graphite has been applied.
As illustrating a desired form of fluxing apparatus, I have shown in Fig. 3 a
fluxing tank G adapted to contain a hot saturated solution of borax and water
which is maintained at the proper temperature by means of a suitable burner G¹.
The advantage of a hot solution is that a greater quantity of sodium bi-borate is
held in the solution and consequently the seam more thoroughly coated than
when the solution is applied cool, and further that the solution will not run to a
material extent when the temperature is reduced on account of crystalization.
The oxidation in brazed joints has been a frequent cause of weakness as the
oxide prevents a close and intermediate union between the spelter and the metal
of which the tube is composed. This oxidation is obviated by the application of
the hot solution referred to which also facilitates the flow of the spelter into
the joint to be brazed. The solution is applied to the joint D' of the tube D
by means of a suitable roller G2 which dips into the solution during its revolu-
tion and thus carries the same into contact with the joint. The roller G² is
supported upon a suitable shaft G3 driven by any suitable power applied to a
band pulley G. The shaft G is supported in oppositely located standards G.
For the purpose of guiding and supporting the tube above and in contact with
this roller G, sheaves H have been provided on opposite sides and are suitably
journaled on the standards G by means of shafts H¹. These shafts are pro-
vided at their upper ends with meshing gear wheels H2 and one of said shafts
has thereon a driving pulley H³ for the application of power in any desired
The sheaves are concaved upon their peripheries and by frictional
contact with the tube hold the same in position while they also move it over
the roller G2 for the application of the flux. The flux is applied by the apparatus
just described in sufficient quantity to fill the joint D' and the fluxing apparatus
is located at such a distance from the remaining parts of the apparatus that
the flux is allowed to cool and crystalize before being further acted upon.
manner.
After the flux is suitably cooled, the excess of borax or flux is removed by
means of a wiper belt I which contacts with the under side of the tube to
cleanse the same from any flux which may remain thereon. This belt is located
at an oblique angle to the length of the tube so as to not affect the movement
of the same in its travel which would be the case were the belt arranged at
right angles to the tube. The belt is suitably driven by means of pulleys I' at
each end thereof which are secured upon shafts I2 located in bearing blocks 13 and
one of said shafts is provided with any desired driving means such as a pulley I'.
Upon the shafts Is there are also located driving pulleys J which carry and
move the graphite applying belt J. This belt is located in the upper part of
the casing Ja and beneath the belt a brush J3 is suitably journaled in the casing.
This brush is adapted to revolve in contact with the graphite contained in the
box and apply the same to the under surface of the belt J, which, in its move-
ment, passes in contact with the joint D' and applies thereto the graphite. The
object of thus applying dry graphite to the joint is that the spelter or solder will
not adhere to the surfaces upon which the graphite has been applied and thus
all projections or roughness upon the outer surface of the tube is prevented and
as the solder does not escape from the joint the exterior surface of the tube is
retained in a clean and polished condition.
The graphite also prevents direct application of heat to solder which might
cause it to swell (and probably drop down out of the joint), thus producing a
rough and imperfect joint and the said graphite applied as described causes an

page_text: indirect course of heat to the solder by way of convection through the metal to
the points which are to be joined.
It may be stated that the solder or spelter can be applied by hand to the
interior of the tube to be brazed and will rest upon the inner surface of the
joint. The flux is then applied and in its liquid condition saturates the joint,
after which the surplus is removed by the wiper belt. This leaves a slight
moisture which will cause the dry graphite to adhere, or if this moisture is not
present, the graphite will adhere to the surface of the metal by reason of the
slight roughness which will receive and retain the light coating of dry graphite
applied by the belt. The graphite is not applied in sufficient quantities to fill
the joint from the outside and the crystalized flux will also prevent the entrance
of graphite into the joint.
Where wet graphite has been employed, the flux becomes spread away from
the joint and adheres to the article in such manner as not only to produce a
wastage of flux but to disfigure the resulting work. On the other hand, by the
The cause of
use of dry graphite no such wastage or disfigurement occurs.
this condition in the use of wet graphite is that the water or other medium of
the mixture under the influence of the brazing heat boils or bubbles and also
dissolves and thins the mixture so that the spelter is defused from the joint by
the chemical action of ebullition.
The wiping and graphite applying belts have been illustrated as located upon
the same driving shaft but it is obvious that the same may be disassociated or
may be located at different points as convenience may dictate. The tube may
likewise be suitably guided in its movement to and from the heater by means of
guide sheaves K journaled upon standards K' which retain and guide the tube in
proper position to enter the heater and to be acted upon by the other apparatus-
as herein before described. It may be stated that the various parts of the heater
can be formed of fire brick or other non-conducting material which will retain
the heat in the brazing chamber.
It is obvious that numerous changes may be made in the construction and
location of the several parts herein before described without departing from the
spirit of the invention as defined by the appended claims.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:--
1. In a brazing machine, the combination with an enclosed brazing chamber,
of a heating device located adjacent thereto, and a carrier having a member
travelling through said chamber to support the article to be brazed adjacent to
said heating device, substantially as specified.
2. In a brazing machine, the combination with a brazing chamber, of a
heating device located adjacent thereto, a carrier provided with fingers adapted
to travel through said chamber and to support the article to be brazed adjacent
to said heating device, substantially as specified.
3. In a brazing machine, the combination with a brazing chamber, of a
heating device located adjacent thereto, a carrier adapted to support the article
to be brazed in said chamber, and fingers travelling through said chamber and
provided with a refractory portion to contact with the article to be brazed, sub-
stantially as specified.
4. In a brazing machine, the combination with a brazing chamber, of a
heating device located adjacent thereto, an endless carrier travelling in a vertical
plane and provided with vertically extending fingers adapted to support the
article to be brazed adjacent to said burner, substantially as specified.
5. In a brazing machine, the combination with a brazing chamber, of a
heating device located adjacent thereto and an endless carrier composed of links
provided with fingers extending at an angle thereto and having refractory tips
to support the article to be brazed, substantially as specified.

page_text: G. In a brazing machine, the combination with a brazing chamber, of a
heating device located adjacent thereto, and a conveyer provided with extended
fingers having removable refractory tips carried thereby, substantially as
specified.
7. In a brazing machine, the combination with a brazing chamber provided
with an opening extending the length thereof, a heating device extending longi-
tudinally of said opening, and means for conveying the material through said
chamber, substantially as specified.
S. In a brazing machine, the combination with a brazing chamber provided
with an opening extending the length thereof, of a heating device extending
longitudinally of said opening, means for conveying the material through said
chamber, and means for vertically adjusting said heating device, substantially
as specified.
9. In a brazing machine, the combination with a brazing chamber, of a
burner centrally located beneath said chamber and having downwardly projecting
walls at the flame orifice of said burner, which walls are enclosed at their lower
portions, substantially as specified.
10. In a brazing machine, the combination with a brazing chamber, of a
burner centrally located beneath said chamber, a horizontal top surface to said
burner provided with downwardly projecting walls, and an enclosing cap
surrounding the lower portion of said walls and extending adjacent to the top
of said burner, substantially as specified.
11. In a brazing machine, the combination with a brazing chamber, of a
passage in communication with and surrounding said chamber, a heating device
located beneath said chamber, and means for supporting the article to be brazed
above said heating device, substantially as specified.
12. In a brazing machine, the combination with a brazing chamber and a
passage in communication with and surrounding said chamber, of a heating
device located beneath said chamber, means for supporting the article to be
brazed above said heating device, and an endless carrier provided with fingers
projecting into said brazing chamber during a portion of its circuit and
travelling across the hot air outlet from said passage during another portion of
their circuit, substantially as specified.
13. In a brazing machine, the combination with a brazing chamber, of a
burner located adjacent thereto, an endless carrier provided with fingers to sup-
port the article to be brazed, a foundation for said heater provided with ways, and
projecting lugs extending from said carrier and travelling in said ways, sub-
stantially as specified.
14. In a brazing machine, the combination with a brazing chamber having an
opening at its upper portion, of heat conducting flues traversing the outer sur-
face of said chamber, a burner beneath said chamber, endless carriers located
upon opposite sides of said chamber and provided with fingers extending there-
into, and means for moving said carriers, substantially as specified.
15. In a brazing machine, the combination with a brazing chamber, of a
burner beneath said chamber provided with flame orifices adapted to concentrate
the heat therefrom at the central portion of said chamber and a carrier provided
with a refractory portion extending into said brazing chamber to support the
article to be brazed, substantially as specified.
16. A brazing machine comprising a brazing chamber, a flux applying
apparatus, a wiper, and a graphite applying device arranged between said wiper
and chamber, substantially as specified.
17. A brazing machine comprising a brazing chamber, a flux applying.
apparatus, a wiper, and a graphite applying device arranged obliquely to the line
of travel of the article to be brazed, substantially as specified.
18. A brazing machine comprising a brazing chamber, carriers travelling
therein, a flux applying device, a wiper located to move in a path obliquely to
the line of travel of said carriers, a graphiting device located parallel to said

page_text: wiper, and means for guiding the article to be brazed into contact with said
several devices, substantially as specified.
19. A brazing machine comprising a brazing chamber, a flux applying
roller, a receptacle beneath said roller to contain liquid flux, and guiding sheaves
located above said roller to engage the article to be brazed and hold it in contact
with said roller, substantially as specified.
20. A brazing machine comprising a brazing chamber, a flux applying
roller, a liquid flux receptacle beneath said roller, guiding sheaves located above
said roller at opposite sides thereof and positively driven for moving the article
to be brazed in contact with said roller, and a heater located beneath said flux
receptacle, substantially as specified.
21. A brazing machine comprising a brazing chamber, a flux applying
device, a wiper comprising an endless belt located obliquely to the line of travel
of the tube to be brazed, and means for guiding and holding said tube in contact
with said wiping belt, substantially as specified.
22. A brazing machine comprising a brazing chamber, a fluxing device, a
wiping device, a graphite applying belt located above a graphite receptacle, means
for applying graphite to the under side of said belt, and means for guiding and
retaining the article to be brazed in contact with said belt, substantially as
specified.
23. A brazing machine comprising a brazing chamber, a burner beneath said
chamber, an endless carrier adapted to support an article to be brazed in said
chamber, a fluxing device, a wiper arranged adjacent thereto, and a graphite
applying device located between said wiper and chamber, substantially as
specified.
24. A brazing machine comprising a heater provided with a brazing chamber,
a burner beneath said chamber, an endless carrier adapted to support an article
to be brazed in said chamber, a fluxing device, a wiper arranged adjacent thereto,
a graphite applying device located between the wiper and chamber, and concave
guiding sheaves adapted to guide and retain the tube to be brazed in contact with
said several devices, substantially as specified.
25. A brazing machine comprising a brazing chamber, a flue extending
adjacent to the outer surface of said chamber and discharging at opposite sides
of said chamber, an endless carrier provided with refractory portions extending
into said brazing chamber during a portion of their travel and travelling across
the hot air outlets from said flue during another portion of their travel, a burner
located beneath said brazing chamber, means to drive said endless carriers, a
fluxing device, and means for transferring the article to be brazed from said
fluxing device to said carriers, substantially as specified.
26. An improvement in the art of brazing which consists in the application
of a spelter or solder, the application of a flux, the application of dry graphite
to the outer surface at the joint of the parts to be brazed and the heating of said
joint to fuse said spelter or solder.
27. An improvement in the art of brazing which consists in the application
of dry graphite along and over a joint to be brazed.
1000
BOULT & WADE,
Agents for the Applicant.