Scientific American Supplement, No. 344, August 5, 1882

V >> Various >> Scientific American Supplement, No. 344, August 5, 1882

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Fig. 3 gives the details of the pneumatic connection between the main
piston and the hammer, in which packing and packing glands are dispensed
with. The hammer, G, is of cast steel, bored out to fit the main piston,
F, the latter being also bored out to receive an internal piston, L. A
pin, M, passing freely through slots in the main piston, F, connects
rigidly the internal piston, L, with the hammer, G. When the main piston
is raised by the rocking lever, the air in the space, X, between the
main and internal pistons, is compressed, and forms an elastic medium
for lifting the hammer; when the main piston is moved down, the air in
the space, Y, is compressed in its turn, and the hammer forced down to
give the blow. Two holes drilled in the side of the hammer renew the air
automatically in the spaces, X and Y, at each blow of the hammer.

Figs. 4 to 6, on the next page, represent the medium size forging
hammer, for making forgings in dies, swaging and tilting bars, and
plating edged tools, etc.

The hammer weighs 1 cwt., has a stroke variable from 4 in. to 141/2 in.,
and gives 200 blows per minute; the compressed air space between the
main piston and the hammer is sufficiently long to admit forgings up to
3 in. thick under the hammer.

To make forgings economically, it is necessary to bring them into the
desired form by a few heavy blows, while the material is still in a
highly plastic condition, and then to finish them by a succession of
lighter blows. The heavy blows should be given at a slower rate than the
lighter ones, to allow time for turning the work in the dies or on the
anvil, and so to avoid the risk of spoiling it. In forging with the
steam hammer the workman requires an assistant, who, with the lever
of the valve motion in hand, obeys his directions as to starting and
stopping, heavy or light blows, slow or quick blows, etc; the quickest
speed attainable depending on the speed of the arm of the assistant.
In the movable-fulcrum forging hammer the operations of starting and
stopping, and the giving of heavy or light blows, are under the complete
control of one foot of the workman, who requires therefore no assistant;
and by properly proportioning the diameter of the driving pulley and
size of belt to the hammer, the heavy blows are given at a slower rate
than the light ones, owing to the greater resistance which they offer to
the driving belt.

In this hammer the pneumatic connection, the arrangements for the
starting, stopping, and holding up of the hammer, as well as those for
communicating the motion of the crank-pin to the hammer by means of
a rocking lever and movable fulcrum, are similar to those in the
planishing hammer, differing only in the details, which provide double
guides and bearings for the principal working parts.

[Illustration: LONGWORTH'S POWER HAMMER WITH MOVABLE FULCRUM.]

The movable fulcrum, B, Figs. 4 and 5, consists of two adjustable steel
pins, attached to the fulcrum lever, Q, and turned conical where they
fit in the socket, D. The fulcrum lever is pivoted on a pin, R, fixed in
the framing of the machine, and is connected at its lower extremity
to the nut, S, in gear with the regulating screw, T. The to-and-fro
movement of the fulcrum lever, Q, by which heavy or light blows are
given by the hammer, is placed under the control of the foot of the
workman, in the following manner: U is a double-ended forked lever,
pivoted in the center, and having one end embracing the starting pedal,
P, and the other end the small belt which connects the fast pulley
on the driving shaft, A, with the loose pulley, V, or the reversing
pulleys, W and X. These are respectivly connected with the bevel wheels,
W_{1}, and X_{1}, gearing into and placed at opposite sides of the bevel
wheel, Z, on the regulating screw in connection with the fulcrum lever.
When the workman places his foot on the pedal, P, to start the hammer,
he finds his foot within the fork of the lever, U; and by slightly
turning his foot round on his heel he can readily move the forked
lever to right or left, so shifting the small belt on to either of the
reversing pulleys, W or X, and causing the regulating screw, T, to
revolve in either direction. The fulcrum lever is thus caused to move
forward or backward, to give light or heavy blows. By moving the forked
lever into mid position, the small belt is shifted into its usual place
on the loose pulley, V, and the fulcrum remains at rest. To fix the
lightest and heaviest blow required for each kind of work, adjustable
stops are provided, and are mounted on a rod, Y, connected to an arm of
the forked lever. When the nut of the regulating screw comes in contact
with either of the stops, the forked lever is forced into mid position,
in spite of the pressure of the foot of the workman, and thus further
movement of the fulcrum lever, in the direction which it was taking,
is prevented. The movable fulcrum can also be adjusted by hand to any
required blow, when the hammer is stopped, by means of a handle in
connection with the regulating screw.

In conclusion the author wishes to direct attention to the fact, that in
many of our largest manufactories, particularly in the midland counties,
foot and hand labor for forging and stamping is still employed to an
enormous extent. Hundreds of "Olivers," with hammers up to 60 lb. in
weight, are laboriously put in motion by the foot of the workman, at a
speed averaging fifty blows per minute; while large numbers of stamps,
worked by hand and foot, and weighing up to 120 lb., are also employed.
The low first cost of the foot hammers and stamps, combined with the
system of piece work, and the desire of manufacturers to keep their
methods of working secret, have no doubt much to do with the small
amount of progress that has been made; although in a few cases
competition, particularly with the United States of America, has forced
the manufacturer to throw the Oliver and hand-stamp aside, and to employ
steam power hammers and stamps. The writer believes that in connection
with forging and stamping processes there is still a wide and profitable
field for the ingenuity and capital of engineers, who choose to
occupy themselves with this minor, but not the less useful, branch of
mechanics.

* * * * *

THE BICHEROUX SYSTEM OF FURNACES APPLIED TO THE PUDDLING OF IRON.

Since the year 1872, the large iron works at Ougree, near Liege, have
applied the Bicheroux system of furnaces to heating, and, since the
year 1877, to puddling. The results that have been obtained in this
last-named application are so satisfactory that it appears to us to be
of interest to speak of the matter in some detail.

The apparatus, which is shown in the opposite page, consists of three
distinct parts: (1) a gas generator; (2) a mixing chamber into which
the gases and air are drawn by the natural draught, and wherein the
combustion of the gases begins; and (3) a furnace, or laboratory (not
represented in the figure), wherein the combustion is nearly finished,
and wherein take place the different reactions of puddling. These three
parts are given dimensions that vary according to the composition of the
different coals, and they may be made to use any sort of coal, even
the fine and schistose kinds which would not be suitable for ordinary
puddling. The gases and the air necessary for the combustion of these
being brought together at different temperatures, and being drawn into
the mixing chamber through the same chimney, it will be seen that the
dimensions of the flues that conduct them should vary with the kind of
coal used; and the manner in which the gases are brought together is not
a matter of indifference.

[Illustration: THE BICHEROUX SYSTEM OF FURNACE.

Vertical Section, and Horizontal Section through MNOPQR]

The gas generator consists of a hopper, A, into which drops, through
small apertures a, the coal piled up on the platform, D. These apertures
are closed with coal or bricks. The bottom of the generator is formed of
a small standing grate. The coal, on falling upon a mass in a state of
ignition, distills and becomes transformed into coke, which gradually
slides down over a grate to produce afterward, through its own
combustion, a distillation of the coal following it. But as these are
features found in all generators we will not dwell upon them.

The gases that are produced flow through a long horizontal flue, B, into
a vertical conduit, E, into which there debouches at the upper part a
series of small orifices, F, that conduct the air that has been heated.
The gases are inflamed, and traverse the furnace c (not shown in the
cut), from whence they go to the chimney. Before the air is allowed to
reach the intervening chamber it is made to pass into the sole of the
furnace and into the walls of the chamber, so that to the advantage of
having the air heated there is joined the additional one of having those
portions of the furnace cooled that cannot be heated with impunity.

The incompletely burned gases that escape from the furnace are utilized
in heating the boilers of the establishment. The dimensions given these
furnaces vary greatly according to the charge to be used. All the
results at Ougree have been obtained with 400 kilogramme charges,
and the dimensions of the gas generators have been calculated for
Six-Bonniers coal, which does not yield over 20 per cent. of gas.

The advantages of this system, which permits of expediting all the
operations of puddling, are as follows:

1. A notable economy in fuel, both as regards quantity and quality.

2. Economy resulting from diminution in the waste of metal, with a
consequent improvement in the quality of the products obtained.

3. Diminution in cost of repairs.

4. Less rapid wear in the grates.

5. Improvement in the conditions of the work of puddling.

As regards the first of these advantages, it may be stated that the
puddling of ordinary Ougree forge iron, which required with other
furnaces 900 to 1,000 kilogrammes of coal, is now performed with less
than 600 kilogrammes per ton of the iron produced. The puddling of fine
grained iron which required 1,300 to 1,500 kilogrammes of coal is now
done with 800. So much for quantity; as for quality the system presents
also a very marked advantage in that it requires no rolling coal--the
operation of the furnace being just as regular with fine coal, even that
sifted through screens of 0.02 meter.

The second class of advantages naturally results from the almost
complete prevention of access of cold air. The saving in wastage amounts
to 3 or 4 per cent., that is to say, 100 kilogrammes of iron produced is
accompanied by a loss of only 9 to 10 kilogrammes, instead of 13 to 15
as ordinarily reckoned.

The diminution in the cost of repairs is due to the fact that the
furnace doors, of which there are two, permit of easy access to all
parts of the sole; moreover, the coal never coming in contact with the
fire-bridges, the latter last much longer than those in other styles of
furnaces, and can be used for several weeks without the necessity of
the least repair. The reduced wear of the grates results from the low
temperature that can be used in the furnace, and the quantity of clinker
that can be left therein without interfering with its operation, thus
permitting of having the grates always black. These latter in no wise
change, and after five months of work the square bars still preserve
their sharpness of edges.

As for the improvements in the conditions of the work of puddling, it
may be stated that with a uniform price per 100 kilogrammes for all the
furnaces, the laborers working at the gas furnaces can earn 25 to 30 per
cent. more than those working at ordinary furnaces.

* * * * *

GESSNER'S CONTINUOUS CLOTH-PRESSING MACHINE.

It is well known that there are several serious drawbacks in the usual
plan of pressing woolen or worsted cloths and felts with press plates,
press papers, and presses. Three objections of great weight may be
mentioned, and events in Leeds give emphasis to a fourth. The three
objections are--the labor required in setting or folding the cloth,
the expense of the press papers, and the time required. The fourth
objection, about which a dispute has occurred between the press-setters
and the master finishers in Leeds, refers to the inapplicability of the
common system to long lengths. The men object to these on account of
the great labor involved in shifting the heavy mass of cloth and press
plates to and from the presses. A minor drawback of this system is
that it involves the presence of a fold up the middle of the piece. On
account of these drawbacks it has long been understood to be desirable
to expedite the process, and also to dispense with the press papers.
This is the main purpose of the machine we now illustrate in section, in
which the pressing is done continuously by what may be termed a species
of ironing. The machine consists of a central hollow cylinder, C,
three-quarters of the circumference of which is covered by the hollow
boxes, M, heated by steam through the pipes shown, and which are
mounted upon the levers, BB', whose fulcra are at bb. By means of the
hand-wheel, T, and worm-wheel, n, which closes or opens the levers, BB',
the pressure of the boxes upon the central roller may be adjusted at
will, the spring-bolt, F, allowing a certain amount of yield. The faces
of the press-boxes, MM, are covered by a curved sheet of German silver
attached to the point, Y. This sheet takes the place of the press papers
in the ordinary process. The course of the cloth through the machine is
as follows, and is shown by the arrows: It is placed on the bottom board
in front, and in its travel it passes over the rails, O, after which it
is operated on by the brush, Z, leaving which it is conveyed over the
rails, V and I, the rollers, K and P, and thence between the pressing
roller, C, and the German silver press plate covering the heated boxes,
M. Leaving these the piece passes over the roller, P, and is cuttled
down in the bottom board by the cuttling motion, F, or a rolling-up
motion may be applied. The maker states that arrangements for brushing
and steaming may also be attached, so that in one passage through the
machine a piece may be pressed, brushed, and steamed. The speed of the
cylinder may be adjusted according to the quality or requirements of
the goods that are under treatment. At the time of our visit, says the
_Textile Manufacturer_, printed woolen pieces were being pressed at the
rate of about four yards a minute, but higher speeds are often obtained.
Messrs. Taylor, Wordsworth & Co., who have erected many of these
machines in Leeds, Bradford, and Batley, inform us that they find they
are adapted for the pressing of a wide variety of cloths, from Bradford
goods and thin serges to the heavy pieces of Dewsbury and Batley. The
inventor, Ernst Gessner, of Aue, Saxony, adopts an ingenious expedient
for pressing goods with thick lists. He provides an arrangement for
moving the cylinder endwise, according to the different widths of
the pieces to be treated. One list is left outside at the end of the
cylinder, and the other at the opposite end of the pressing boxes. The
machine we saw was 80 in. wide on the roller, and it was one the design
and construction of which undoubtedly do credit to Mr. Gessner.

[Illustration]

* * * * *

IMPROVEMENTS IN WOOLEN CARDING ENGINES.

Mr. Bolette, who has made a name for himself in connection with strap
dividers, has experimented in another direction on the carding engine,
and as his ideas contain some points of novelty we herewith give the
necessary illustrations, so that our readers can judge for themselves as
to the merit of these inventions.

[Illustration: Fig. 1.]

Fig. 1 represents the feeding arrangement. Here the wool is delivered by
the feed rollers, A A, in the usual manner. The longer fibers are then
taken off by a comb, B, and brought forward to the stripper, E, which
transfers them to the roller, H, and thence to the cylinder. The shorter
fibers which are not seized by the comb fall down, but as they drop
they meet a blast of air created by a fan, which throws the lighter and
cleaner parts in a kind of spray upon the roller, L, whence they pass on
to the cylinder, while the dirt and other heavier parts fall downwards
into a box, and are by this means kept off the cylinder. It is evident
that in this arrangement it is not intended to keep the long and the
short fibers separate, but to utilize them all in the formation of
the yarn. The arrangement shown in Fig. 2 refers to the delivery end.
Instead of the sliver being wound upon the roller in the usual way, it
runs upon a sheet of linen, P, as in the case of carding for felt, with
a to-and-fro motion in the direction of the axis of the rollers. In this
way one or more layers of the fleece can be placed on the sheet, which
in that case passes backwards and forwards from roller S to R, and _vice
versa_. It is, in fact, the bat arrangement used for felt, only with
this difference, that the bat is at once rolled up instead of going
through the bat frame. In the manufacture of felt it is of course of
importance to have many very thin layers of fleece superposed over
each other in order to equalize it, and if the same is applied to the
manufacture of cloth it will no doubt give satisfactory results, but may
be rather costly.

[Illustration: Fig. 2.]

* * * * *

NOVELTIES IN RING SPINDLES.

One of the drawbacks of ring spinning is the uneven pull of the
traveler, which is the more difficult to counteract as it is exerted
in jerks at irregular intervals. It is argued that with spindles and
bearings as usually made the spindle is supported firmly in its bearing,
and cannot give in case of such a lateral pull when exerted through the
yarn by the traveler, and the consequence is either a breakage of the
yarn or an uneven thread. Impressed with this idea, and in order to
remedy this defect, an eminent Swiss firm has hit upon the notion of
driving the spindle by friction, and to make it more or less loose in
the bearings, so that in case of an extra pull by the traveler the
spindle can give way a little, and thus prevent the breakage of the
yarn. This idea has been carried out in four different ways, and as this
seems to be an entirely new departure in ring spinning, we give the
illustrations of their construction in detail.

[Illustration: Fig. 1. Fig. 2. Fig. 3. Fig. 4.]

Fig. 1 represents Bourcart's recent arrangement of attaching the thread
guide to the spindle rail and the adjustable spindle. The spindle is
held by the sleeve, g, which latter is screwed into the spindle rail, S,
this being moved by the pinion, a; the collar is elongated upwards in a
cuplike form, c, the better to hold the oil, and keep it from flying;
d is the wharf, which has attached to it the sleeve, m, and which is
situated loosely in the space between the spindle and the footstep, e.
Above the wharf the spindle is hexagonal in shape, and to this part is
attached the friction plate, a. Between the latter and the upper surface
of the wharf a cloth or felt washer is inserted, to act as a brake. The
footstep, e, is filled with oil, in which run the foot of the spindle
and the sleeve m, the latter turning upon a steel ring situated on the
bottom of the footstep. As, thus, the foot of the spindle is quite free,
the upper part of the spindle can give sideways in the direction of any
sudden pull, and the foot of the spindle can follow this motion in the
opposite direction, the collar forming the fulcrum for the spindle. By
this alteration of the vertical position of the spindle into an inclined
one (though ever so trifling), the contact of the friction plate, a, and
the wharf is interrupted, and thus the speed of the spindle reduced.
This will cause less yarn to be wound on, and the pull thus to be
neutralized; but as the wharf keeps turning at the same speed, its
centrifugal force will act again upon the friction plate, and thus bring
the spindle back to its vertical position as soon as the extra drag has
been removed.

In Fig. 2 the footstep, e, has the foot of the spindle more closely
fitting at the bottom, but the upper part of the step opens out
gradually, and forms a conical cavity of a little larger diameter than
the spindle, so that the latter has a considerable play sideways. The
wharf carries in its lower part the sleeve, g, which runs upon a steel
ring as above. The upper surface of the wharf is arched, and upon this
is fitted the correspondingly arched friction plate, a, which latter
is attached to the spindle by a screw. The position of the spindle is
maintained by the collar, m. This collar is loose in the spindle rail,
and only held by the spring, m'. If now, a lateral drag is exerted upon
the upper part of the spindle, the collar car follows the direction of
this drag, and the spindle thus be brought out of the vertical position,
the friction plate slipping at the same time. The force of the spring
conjointly with the centrifugal force will then bring back the spindle
into its normal position as soon as the drag is again even.

Fig. 3 shows a spindle with a very long conical oil vessel, B, resting
upon a disk, e", in cup, e', with a cover, e"'. The wharf, d, is here
situated high up the spindle, has the same sleeve as in the preceding
case, and runs round the bush, g, upon the ring, z. The friction plate
resting upon the wharf is joined to the collar, a, running out into a
cup shape, which is fixed to the spindle, which here has a hexagonal
form. In this case the collar gives with the spindle, which latter
has the necessary play in the long footstep; and as the collar and
friction-plate are one, it is brought back to its normal place by
centrifugal force.

A peculiar arrangement is shown in Fig. 4. Here the ring and traveler,
f, are placed as usual, but the spindle carries at the same time an
inverted flier, t. The spindle turns loosely in the footstep, e, the
oil chamber being carried up to the middle of its height. The wharf
is placed in the same position as in the previous case, having also
a sleeve running in the oil chamber, c, upon a steel ring, z. The
friction-plate a, on the top of the wharf carries the flier, and on its
upper surface is in contact with the inverted cup, a, which is attached
to the spindle by a pin or screw. In order to limit at will the lateral
motion of the spindle there is attached to the latter, between the
footstep and the collar, a split ring, i, which can be closed more
or less by a small set screw. The spindle is thus only held in the
perpendicular position by its own velocity, which will facilitate a
high degree of speed, through the entire absence of all friction in the
bearings, this vertical position being assisted by the friction motion
whenever the spindle has been drawn on one side. Although the notion of
mounting spindles so that they can yield in order to center themselves
is not new, it is evident that considerable ingenuity has been brought
to bear upon the arrangement of the spindles we have described, but we
are not in a position to say to what extent practice has in this case
coincided with theory.--_Textile Manufacturer_.

* * * * *

PHOTO-ENGRAVING ON ZINC OR COPPER.

By LEON VIDAL.

This process is similar in many respects to the one which was some
time ago communicated to the Photographic Society of France by M.
Stronbinsky, of St. Petersburg, but in a much improved and complete
form. An account of it was given by M. Gobert, at the meeting of the
same society, on the 2d December, 1882. The following are the details,
as demonstrated by me at the meeting of the 9th of May last:

Sheets of zinc or of copper of a convenient size are carefully planished
and polished with powdered pumice stone. The sensitive mixture is
composed of:

The whites of four fresh eggs beaten
to a froth......................... 100 parts
Pure bichromate of ammonia......... 2.50 "
Water.............................. 50 "

After this mixture has been carefully filtered through a paper filter, a
few drops of ammonia are added. It will keep good for some time if well
corked and preserved from exposure to the light. Even two months after
being prepared I have found it to be still good; but too large a
quantity should not be prepared at a time, as it does not improve with
keeping.

I find that the dry albumen of commerce will answer as well as the
fresh. In that case I employ the following formula:

Dry albumen from eggs.............. 15 to 20 parts
Water.............................. 100 "
Ammonia bichromate................. 2.50 "

Always add some drops of ammonia, and keep this mixture in a well corked
bottle and in a dark place.

To coat the metal plate, place it on a turning table, to which it is
made fast at the center by a pneumatic holder; to assure the perfect
adhesion of this holder, it is as well to wet the circular elastic ring
of the holder before applying it to the metallic surface. When this is
done, the table may be made to rotate quickly without fear of detaching
the plate by the rapidity of the movement. The plate is placed in a
perfectly horizontal position, where no dust can settle on it; the
mixture is then poured on it, and distributed by means of a triangular
piece of soft paper, so as to cover equally all the parts of the plate.
Care should be taken not to flow too much liquid over the plate, and
when the latter is everywhere coated, the excess is poured off into a
different vessel from that which contains the filtered mixture, or else
into a filter resting on that vessel. The turning table should now be
inverted so that the sensitive surface may be downwards, and it is made
to rotate at first slowly, afterwards more rapidly, so as to make the
film, which should be very thin, quite smooth and even. The whole
operation should be carried out in a subdued light, as too strong a
light would render insoluble the film of bichromated albumen.

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