Improvements in the Pneumatic Action of Power Hammers.
Year: 1892

page_text: Date of Application, 28th Sept., 1892
Complete Specification Left, 7th June, 1893—Accepted, 8th July, 1893
PROVISIONAL SPECIFICATION.
Improvements in the Pneumatic Action of Power Hammers.
I, SAMUEL WILSON AMPHLET, of No. 98 Hagley Road, Birmingham in the
County of Warwick, Mechanical Engineer do hereby declare the nature of this
invention to be as follows:-
My invention has reference to hammers of the kind known as power hammers,
that is, hammers driven by a belt or other gearing from a steam or other motive
power engine in contradistinction to hammers driven directly by steam or com-
pressed air. My said invention consists of the arrangements or combinations of
parts hereinafter described for cushioning the said hammers by means of an air
cushion so as to relieve the mechanism of the hammer from the shock of the blow
of the hammer and to permit of the operator determining at will the character of
the blow given, that is to permit of a light or heavy elastic blow.
دو
I will describe my invention as applied to a power hammer driven by a belt from
a steam engine. At the summit of the frame of the machine is a crank shaft
having fast and loose pulleys and a fly wheel. A connecting rod depends
vertically from the said crank and is connected with the top of an air cylinder
which slides vertically in guides in the frame of the machine. The said cylinder is
provided with a piston and piston rod, the piston rod passing through a stuffing
box in the bottom of the cylinder and carrying at its lower end the "tup of the
hammer. The cylinder described I will hereinafter call the principal cylinder.
Connected with the principal cylinder and preferably cast in one piece with it is
another parallel cylinder of about the same length but of much smaller diameter
(say about one third) which I will hereinafter call the small cylinder. At that
side of the principal cylinder carrying the small cylinder a series of holes is made
the said holes being in a vertical line and at levels distant from each other about
equal to the thickness of the piston in the principal cylinder. In the small
cylinder is a drum or cylinder filling the said small cylinder and turning in bearings
at the top and bottom respectively of the small cylinder. The said drum is
capable of rotating in the said small cylinder but is incapable of vertical motion
therein. The said drum has two series of holes arranged helically so that two of
the said holes shall be at the same time coincident with two of the holes in the
principal cylinder. On turning the said drum through a certain angle its bottom
pair of holes can be brought opposite the bottom pair of holes in the principal
cylinder all the other holes in the principal cylinder being closed. By turning the
drum through a greater angle its second higher pair of holes may be brought
opposite the second higher pair of holes in the principal cylinder, all the other
holes in the principal cylinder being closed; and so on with respect to the other
pairs of holes. All the holes in the drum are in communication with the
atmosphere. By the arrangement described the volume of air below the piston in
the principal cylinder can be varied and the said piston and the tup fixed to the
piston rod can be suspended at any required height and the character of the blow
of the hammer varied at the will of the workman.
Instead of making pairs of holes in the cylindrical face of the drum for the
purpose described, a helical or curved slot may be cut therein the said slot being
in communication with the atmosphere so that on the turning of the said drum the
said slot may be brought opposite any one of the pairs of holes in the principal
cylinder, the other pairs of holes being closed. The drum bas the necessary
angular motion communicated to it by a vertical shaft on which it is capable of a
rising and falling motion but is incapable of a rotary motion thereon. The said

page_text: vertical shaft turns in bearings carried by the frame of the machine and may have
an angular motion communicated to it by a treadle or by hand.
I do not limit myself to the distance apart of the holes in the principal cylinder
and drum as holes at a distance apart equal to one half or one third or other sub-
multiple of the thickness of the piston may be employed where it is desired to
regulate the blow of the hammer with great nicety.
If thought necessary one or more "snifting or atmospheric valves may be
arranged near the top and bottom of the principal cylinder for supplying air to the
said principal cylinder when the pressure in the space above or below the piston in
the said cylinder is less than the atmospheric pressure.
Dated the 28th day of September 1892.
W. T. WHITEMAN,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Pneumatic Action of Power Hammers.
I SAMUEL WILSON AMPHLET, of No. 98 Hagley Road, Birmingham in the
County of Warwick, Mechanical Engineer do hereby declare the nature of my
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 has reference to hammers of the kind known as power hammers,
that is, hammers driven by a belt or other gearing from a steam or other motive
power engine in contradistinction to hammers driven directly by steam or com-
pressed air. My said invention consists of the arrangements or combinations of
parts hereinafter described for cushioning the said hammers by means of an air
cushion so as to relieve the mechanism of the hammer from the shock of the blow
of the hammer and to permit of the operator determining at will the character of
the blow given, that is, to permit of a light or heavy elastic blow.
I will describe my invention as applied to a power hammer driven by a belt from
a steam engine. At the summit of the frame of the machine is a crank shaft
having fast and loose pulleys and a fly wheel. A connecting rod depends vertically
from the said crank and is connected with the top of an air cylinder which slides
vertically in guides in the frame of the machine. The said cylinder is provided with
a piston and piston rod the piston rod passing through a stuffing box in the bottom of
the cylinder and carrying at its lower end the "tup" of the hammer. The cylinder
described I will hereinafter call the principal cylinder. Connected with the
principal cylinder and preferably cast in one piece with it, is another parallel
cylinder of about the same length but of much smaller diameter (say about one
third) which I will hereinafter call the small cylinder. At that side of the
principal cylinder carrying the small cylinder a series of holes is made the said
holes being in a vertical line and at levels distant from each other about equal to
the thickness of the piston in the principal cylinder. In the small cylinder is a
drum or cylinder filling the said small cylinder and turning in bearings at the top
and bottom respectively of the small cylinder. The said drum is capable of
rotating in the small cylinder but is incapable of vertical motion therein.
said drum has two series of holes arranged helically so that two of the said holes
shall be at the same time coincident with two of the holes in the principal
cylinder. On turning the said drum through a certain angle its bottom pair of
holes can be brought opposite the bottom pair of holes in the principal cylinder,
all the other holes in the principal cylinder being closed. By turning the drum
through a greater angle its second higher pair of holes may be brought opposite
the second higher pair of holes in the principal cylinder, all the other holes in the
principal cylinder being closed, and so on with respect to the other pairs of holes.
All the holes in the drum are in communication with the atmosphere. By the
arrangement described the volume of air below the piston in the principal cylinder
The

page_text: can be varied and the said piston and the tup fixed to the piston rod can be
suspended at any required height and the character of the blow of the hammer
varied at the will of the workman.
Instead of making pairs of holes in the cylindrical face of the drum for the
purpose described a helical or curved slot may be cut therein the said slot being in
communication with the atmosphere so that on the turning of the said drum the
said slot may be brought opposite any one of the pairs of holes in the principal
cylinder, the other pairs of holes being closed. The drum has the necessary angular
motion communicated to it by a vertical shaft on which it is capable of a rising
and falling motion but is incapable of a rotary motion thereon. The said vertical
shaft turns in bearings carried by the frame of the machine and may have an
angular motion communicated to it by a treadle or by hand.
I do not limit myself to the distance apart of the holes in the principal cylinder
and drum as holes at various distances apart may be used to regulate the blow of
the hammer with great nicety.
66
If thought necessary one or more snifting" or atmospheric valves may be
arranged near the top and bottom of the principal cylinder for supplying air to the
Baid principal cylinder when the pressure in the space above or below the piston in
the said cylinder is less than the atmospheric pressure.
I will now describe with reference to the accompanying drawing the manner in
which my invention is to be performed.
Figure represents in front elevation and Figure 2 in vertical section a power
hammer provided with one of the arrangements of my invention for producing the
pneumatic action or cushioning of the piston of the said hammer ;
Figure 2A represents a part of the same drawn to a larger scale;
Figures 3, 4 and 5 represent other arrangements or modifications of my invention
as hereinafter described.
The same letters of reference indicate the same parts in the several figures of
the drawing.
I will first describe the arrangement represented in Figures 1 and 2.
a, a is the frame of the power hammer; is the air or principal cylinder sliding
vertically in guides in the frame a, a of the machine; c is the piston working in
the said air or principal cylinder and having on its underside the piston rod d passing
through a stuffing box at the lower end of the cylinder. The said rod d carries
the tupe of the hammer. The reciprocating motion of the air or principal
cylinder bis effected from the crank shaft the crank of which is connected by the
connecting rod g with the top of the said air or principal cylinder. The crank
shaft has fast and loose pulleys h, i and a fly wheel k. The parts constituting
my invention for obtaining the pneumatic or cushioning action of the hammer,
whereby the character of the blow delivered by the hammer may be determined
at the will of the operator are as follows:-The air or principal cylinder has at
one side and preferably cast in one piece with it another and parallel cylinder / of
about the same length as but of smaller diameter than the principal cylinder b. In
the side of the principal cylinder b and opening into the smaller cylinder / is a
series of holes m arranged in a vertical line and at levels distant from each other
about half the thickness of the piston c in the principal cylinder as represented in
Figure 2. Working closely in the said small cylinder is a hollow cylindrical
drum n (shown detached drawn to a larger scale in Figure 2) supported on the
cover closing the bottom of the said small cylinder 1. The said hollow drum n
is capable of rotating in the said small cylinder but is incapable of vertical motion
therein (see Figure 2). The rotation of the drum through the proper angle for the
purpose of varying the amount of air under the piston in the principal cylinder is
effected in the manner hereinafter described. In the said drum n two series of holes p
are arranged helically, the said holes being at the same distance apart as those of the
vertical row of holes m in the side of the principal cylinder b so that two of the said
holes p shall be at the same time coincident with two of the holes m in the principal
cylinder. In the drawing the top pair of holes p in the drum n is represented
l

page_text: opposite the top pair of holes m in the principal cylinder b, all the other holes in
the principal cylinder being closed. By turning the drum n through the proper
angle any two of the holes in it can be brought opposite a lower pair of holes m in
the cylinder b, all the other holes in the cylinder 6 being closed. The interior of
the rotating drum n is open to the atmosphere by means of the vertical passage at q
passing through the top of the drum and through the top of the small cylinder so
that all the holes in the said drum are in communication with the atmosphere.
Atmospheric air is also admitted to the interior of the drum through a row of
vertical holes in the small cylinder when two holes of the series in the said drum
coincide with a pair of the holes in the said small cylinder as seen in Figure 2.
1"
l
The drum n having two series of holes arranged helically on its cylindrical surface
is rotated through the required angle to bring two of its holes opposite any pair of
the holes m in the principal cylinder in the following manner. Connected to the
bottom of the drum n by a long key s is a vertical shaft t, the said drum in its
reciprocating motion with the two cylinders 6 and sliding upon the said key s and
shaft t. The shaft t carries near its bottom the bevil pinion t with which a bevil
pinion t fixed on the cross horizontal shaft t gears. Rotation is given to the cross
shaft by means of the toothed sector to gearing with the toothed wheel to on the
said shaft (see Figure 1). The toothed sector to turns on the centre t' and its
short arm is connected by the weighted connecting rod t to the pedal to. By
depressing the pedal to the drum n may be rotated through the proper angle, by the
action of the toothed sector t³, toothed wheel t", bevil pinions t², t3 and shaft t, to
bring two of the holes in the said drum opposite a pair of holes at the required level
of the set of holes at m in the principal cylinder b. The toothed sector to may be
worked by hand instead of by a pedal.
In the normal positions of the parts, and when the pedal is unacted upon, two of
the holes of the series p in the drum are situated opposite the top pair of holes of
the series m in the principal cylinder b. When the parts are so arranged, on
working the hammer the volume of air below the piston c to be cushioned is greatest
and consequently a blow nearly of the lightest kind is obtained. In order to vary
the volume of air below the piston c and vary the force or intensity of the blow of
the hammer, the perforated drum n is rotated through the proper angle by the
workman operating the mechanism described so as to bring two holes in the said
drum opposite a lower pair of holes in the principal cylinder b. A less volume of
air as the piston e descends is thereby compressed or cushioned between it and the
bottom of the cylinder and hence the force or intensity of the blow is increased as
is well understood. As the piston descends the air is pressed out of the cylinder at
the coincident holes in the cylinder and drum », the compression or cushioning of
the air commencing immediately the piston passes the said coincident holes.
this way the "tup e fixed to the piston rod can be suspended at any required
height and the character of the blow of the hammer varied at the will of the
workman.
One or more
In
snifting" or atmospheric valves may be placed near the top and
bottom of the principal cylinder b for the purpose hereinbefore stated.
Figures 3 and 4 represent vertical sections of the principal and small cylinders
of a power hammer in which the rotating drum working in the small cylinder
is provided with a helical slot in place of the helical series of holes herein before
described and illustrated;
Figure 5 represents an elevation of the drum of the arrangement Figure 3 drawn
to a larger scale.
In the arrangement Figures 3 and 5, the helical slot in and open to the interior
of the hollow drum n is marked u and extends from near one end to the opposite end
of the drum, the said helical slot having the same width as the holes m and r in the
principal and small cylinders b and l.
Or instead of making the helical slot in the hollow drum n of the same width as
the holes in the cylinders, the helical slot may have a width greater than two of the
holes in the cylinders as represented in Figure 4, the said wide helical slot being

page_text: marked v. The helical slot u or v is open to the atmosphere by the top passage q
and holes in the small cylinder as described with respect to Figure 2. By moving
the drum n in the manner hereinbefore described, the helical slot u or vin it may
be brought opposite any one of the holes, or any pair of the holes, m in the principal
cylinder b, the other holes being closed, for the purpose of varying the volume of
air below the piston c in the principal cylinder and varying the force of the blow of
the hammer as herein before described with respect to the arrangement Figures 1
and 2.
In Figures 3 and 4 the helical slot in the drum is shown brought opposite the top
hole or holes of the set of holes in the principal cylinder b.
Having now particularly described and ascertained the nature of my inven-
tion and the manner in which the same is to be performed I declare that I claim
as my invention of "Improvements in the pneumatic action of power hammers" ;-
The combination with or adaptation to the principal cylinder of the power
hammer of a small or supplementary parallel cylinder in which a hollow drum open
to the atmosphere is capable of rotating, the said principal cylinder being provided
at one side with a vertical row of holes opening into the small cylinder and the
said hollow rotating drum being provided with holes arranged helically, or with a
helical slot, so that by the rotation of the said drum through the proper angle one
or more of the said holes in the drum, or its helical slot, can be made to coincide
with one or more of the holes in the principal cylinder, so as to open the said
principal cylinder to the atmosphere through the hollow drum, all the other holes
in the said principal cylinder being closed, whereby the volume of air below the
piston in the said principal cylinder can be varied and the "tup" fixed to the piston
rod can be suspended at any required height and the character of the blow of the
hammer varied at the will of the workman, the several parts being arranged or
combined and acting substantially as hereinbefore described and illustrated in the
accompanying drawing.
Dated the Fifth day of June 1893.