Improvements in Power Hammers and Stamps.
Year: 1888

page_text: Date of Application, 6th Apr., 1888
Complete Specification Left, 6th Feb., 1889
Complet: Specification Accepted, 4th May, 1889
PROVISIONAL SPECIFICATION.
Improvements in Power Hammers and Stamps.
I, THOMAS BROWETT, of Sandon Works, St. Simon Street Salford in the County of
Lancashire, Engineer, do hereby declare the nature of this invention to be as
follows:--
My invention relates to improvements in that class of hammers or stamps, wherein
a blow is obtained by mechanism driven from a revolving shaft instead of by the direct
application of steam, and it consists of mechanism whereby the trip stamp or hammer
may be lifted to any desired height and may then either be allowed to fall by gravity
on the material to be worked, or may have imparted to it a greater velocity than would
be due to the action of gravity alone according to the nature of the blow required to
be delivered.
For this purpose I construct a hammer of the well known type wherein the trip or
stamp is raised by means of a board or stem of suitable material attached to the
hanımer head, such board being capable of being gripped between a fixed revolving
pulley on one side, and a movable pulley on the other, which can ho caused to move
towards the surface of the board so as to press it onto that face of the revolving pulley
which is working in an upward direction, so that by frictional contact therewith the
stem and hammer are raised.
And my invention consists in causing the said board or stem when so raised, to be
capable of being pressed at will to any desired extent against the surface of another
pulley revolving in an opposite direction, that is, in such a direction that the stem and
hammer will, by frictional contact therewith, be caused to descend towards the anvil
at a higher velocity than that due to gravity alone so that the blow delivered will be
increased in proportion.
To effect this by one method I provide a suitable hammer frame fitted with a hammer
head moving in vertical slides, and attached to the hammer is a board standing
vertical, and of such a length that its upper portion extends, when the hammer is at
rest on the anvil, between the faces of two rollers mounted on suitable spindles
supported in bearings formed on the top of the frame.

page_text: Either or both of these rollers may be caused to rotate by suitable belts and pulleys
deriving motion from any line shaft.
At a convenient distance above these two rollers and their shafts, two similar rollers
and shafts are provided, one or both of which may be caused to rotate but in opposite
directions to those immediately below them, that is, so that the surfaces of these rollers,
between which the board rides, are moving downwards.
In order to cause the board or stem to be gripped between either of these two sets
of rollers, to raise or depress the hammer, respectively, one or both of each pair of
shafts on which the rollers are fixed may be mounted in sliding bearings capable
of being moved by a hand or foot lever, actuating mechanism suitable for obtaining a
considerable pressure, such as an eccentric screw or toggle joint, or the rollers may be
mounted on eccentric bushes threaded on the shaft, a flexible coupling or "Oldham's"
coupling being introduced for the purpose of transmitting the rotary motion of the
shaft to the rollers which ride on the eccentric bushes.
In some cases an elastic cushion of cork, rubber, or like substance, or springs of any
suitable construction, may be introduced as a flexible connection between the hammer
head and the board or stem, to lessen the shock to the board, and to render the blow
more elastic.
The normal position of the hand or foot lever for bringing the rollers into contact
with the stem may be such that both sets of rollers are out of contact and a movement
in one direction will set the lifting rollers in contact, and in a reverse direction will set
the depressing rollers in contact to increase the blow, as explained above.
Either the lifting or depressing rollers or both may be connected to the shafts,
which cause them to rotate by an elastic connection, say a strong spiral spring in
torsion, or springs in compression or tension, so that when the strain due to the lifting
or depressing of the hammer is first thrown onto the pulley or roller, it will yield
somewhat until the inertia of the hammer-head and all parts connected thereto,
is overcome.
Where a continual regular lift and blow is desired, the mechanism used for bringing
the lifting and depressing rollers alternately into action, may readily be mado
automatic and adjustable, and for crushing stone quartz or any substance a series of
heads may be arranged in one frame.
For the purpose of producing a regular vibration of a stamp or hanımer, in some
cases I cut away portions of the revolving friction rollers and so gear the raising and
depressing rollers, relatively, that as soon as the lifting surface of the one ceases to
act, the depressing surface of the other comes into play.
Instead of pressing the rollers against the lifting stem, the stem may be pressed
alternately against the lifting and depressing rollers, and the stem nay be flat, round,
V shaped, or of any convenient section, and of any suitable material, the rollers being
shaped to correspond.
Dated this 31st day of March 1888.
F. BOSSHARDT & Co.,
Agents to Applicant.

page_text: I, THOMAS BROWETT of Sandon Works, St. Simon Street, Salford in the
County of Lancashire, 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:
-
My invention relates to improvements in that class of hammers or stamps wherein
a blow is obtained by mechanism driven from a revolving shaft instead of by the
direct application of steam, and it consists of mechanism whereby the tup, stamp or
hammer may be lifted to any desired height and may then either be allowed to fall
by gravity on the material to be worked, or may have imparted to it a greater
velocity than would be due to the action of gravity alone, according to the nature of
the blow required to be delivered.
For this purpose 1 construct a hammer of the well known type wherein the tup
or stamp is raised by means of a board or stem of suitable material attached to the
hammer head, such board being capable of being gripped between a fixed rovolving
pulley on one side, and a movable pulley on the other, which can be caused to move
towards the surface of the board so as to press it onto that face of the revolving
pulley which is working in an upward direction, so that by frictional contact there-
with the stem and hammer are raised.
And my invention consists in causing the said board or stem when so raised, to
be capable of being pressed at will to any desired extent against the surface of
another pulley revolving in an opposite direction, that is, in such a direction that the
stem and hammer will, by frictional contact therewith, be caused to descend towards
the anvil at a higher velocity than that due to gravity alone so that the blow delivered
will be increased in proportion.
To effect this by one method I provide a suitable hammer framo fitted with a
hammer head moving in vertical slides, and attached to the haminer is a board
standing vertical, and of such a length that its upper portion extends, when the
hammer is at rest, on the anvil, between the faces of two rollers mounted on suitable
spindles supported in bearings formed on the top of the frame.
Either or both of these rollers may be caused to rotate by suitable belts and
pulleys deriving motion from any line shaft.
At a convenient distance above these two rollers and their shafts, two similar
rollers and shafts are provided, one or both of which may be caused to rotate but in
opposite directions to those immediately below them, that is, so that the surfaces of
these rollers, between which the board rides, are moving downwards.
In order to cause the board or stem to be gripped between either of these two
sets of rollers, to raise or depress the hammer, respectively, one or both of each pair
of shafts on which the rollers are fixed may be mounted in sliding bearings capable
of being moved by a hand or foot lever, actuating mechanism suitable for obtaining
a considerable pressure, such as an eccentric screw, or toggle-joint, or the rollers
may be mounted on eccentric bushes threaded on the shaft, a flexible coupling or
"Oldhams'" coupling being introduced for the purpose of transmitting the rotary
motion of the shaft to the rollers which ride on the eccentric bushes.
In some cases an elastic cushion of cork, rubber, or like substance, or springs of

page_text: any suitable construction may be introduced as a flexible connection between the
hammer head and the board or stem, to lessen the shock to the board, and to render
the blow more elastic.
The normal position of the hand or foot lever for bringing the rollers into contact
with the stem may be such that both sets of rollers are out of contact and a move-
ment in one direction will set the lifting rollers in contact, and in a reverse direction
will set the depressing rollers in contact to increase the blow, as explained above.
Either the lifting or depressing rollers, or both, may be connected to the shafts
which cause them to rotate by an elastic connection, say a strong spiral spring in
torsion, or springs in compression or tension, so that when the strain due to the lifting
or depressing of the hammer is first thrown onto the pulley, or roller, it will yield
somewhat until the inertia of the hammer head and all parts connected thereto, is
overcome.
Where a continual regular lift and blow is desired, the mechanism used for bringing
the lifting and depressing rollers alternately into action, may readily be made
automatic and adjustable, and for crushing stone quartz or any substance, a series of
heads may be arranged in one frame.
For the purpose of producing a regular vibration of a stamp or hammer, in some
cases I cut away portions of the revolving friction. rollers and so gear the raising and
depressing rollers, relatively, that as soon as the lifting surface of the one ceases to
act, the depressing surface of the other comes into play.
Instead of pressing the rollers against the lifting stem, the stem may be pressed
alternately against the lifting and, depressing rollers, and, the stem may be flat, round,
V shaped, or of any convenient section, and of any suitable material, the rollers being
shaped to correspond.
...
And in order that my invention may be more fully understood 1 have caused to
be appended hereunto one sheet of drawings marked with letters of reference, similar
letters indicating like parts in the various figures.
Fig. 1 shows a side elevation and Fig. 2 a back elevation of a hammer constructed
in accordance with my improvements.
Fig. 3 is a plan of the head-stock containing the lifting gear, the depressing rollers
being supposed to be removed for the sake of clearness.
In Figs. 1, 2 & 3, 1 is the main frame or standard of the hammer; 2 the stem of
the hammer or tup 3, 4 & 5 are the lifting rollers mounted on shafts 6 & 7 carried in
eccentric bushes &, 9, 10 & 11, all fitting in suitable bearings formed in the head-
stock.
.
Each pair of these eccentric bushes is connected together by arms 12, 13, 14, 15,
and connecting stays 16 & 17. (Fig. 3).
The two depressing rollers 18 & 19 are of exactly similar construction and
arrangement being mounted on shafts 20 & 21 carried in eccentric bushes, two of
which are figured 22 & 23; in Fig. 1: These bushes, two on each-shaft-are-connected
in pairs by arms and stays precisely as described with reference to the lifting rollers
and shafts. One of these arms is figured 24 and its stay is connected.to the stay:17
by the link 25. A rod 26 is connected to the stay 17, and is capable of being
actuated by the hand lever' 27.
.
The shafts or spindles 71 & 20 are driven by pullies 28 & 29, and the shafts, 6 & 21
may (when it is desired to drive both of each set of rollers) be geared together by the
spur wheels 30, 31 32 & 33, of which wheels the pitch circles only are shown in
Fig. 1. to prevent confusion: "
L.. kr .'.. 14
*
The rollers 4, 5, 18 & 19 may either be keyed fast. to their respective shafts.6, 7,
20 & 21,
or the motion of these shafts may be transmitted as shown in Figs: 4 & 5,
which show a longitudinal and transverse section respectively. of a roller. constructed
of a cylindrical ring and end plates and attached to the spindle 6 by a volute or coiled
flat steel spring 34 attached at its inner end to the spindle 6 and provided at its free
end with a detent 35-taking into a series of ratchet teeth.36 extending all round the
inner surface of the roller 4. By this construction the shaft. 6.drives the roller 4 by
the intervention of the spring 34, and if, during the fall of the hammer and stem 2,

page_text: its velocity becomes higher than the periphery velocity of the roller 4,-such roller is
free to rotate at a higher velocity than its driving shaft.
Figs. 6 & 7 show a similar spring connected between the roller and shaft 'but
without the internal rack.
This construction may be used either for the lifting or depressing rollers but is more
suitable for lifting. The end of the spring 34 is bolted to the spindle or shaft
and the other end to the roller.
Figs. 8 & 9 show a plan and end olevation of a frictional gripping device to sustain
the hammer when lifted off the anvil. It consists of two cross heads 37 & 38, capable
of being drawn together by right and left hand screws 39 & 40, which screws are
geared together by spur pinions 41 & 42. Into each of these cross heads is fitted
a block or wedge 43 & 44, free to slide therein and held in its highest position
by a spiral spring 45, shown more clearly in Figs. 9 & 10 in detail.
These wedges 43 & 44 are arranged to grip the edges of the board or stem 2
on its downward movement when these wedges are brought into frictional contact
therewith by causing the crossheads 37 & 38 to approach each other.
By rotating the screws in a reverso direction the wedges are released and the
hammer head allowed to fall.
A spur segment 46 (Fig. 1) is shown connected to the eccentric bush 10 and
gearing with the wheel 42 so as to be actuated by the lever 27.
Fig. 11. shows the modification referred to in my Provisional Specification
whereby a continuous reciprocating motion may be imparted to a hammer or
stamp by means of lifting and depressing rollers 4, 5, 18, & 19, but in this arrange-
ment the rollers are cut away on their surfaces where they grip the stem 2 so as
to come into frictional contact therewith for a part only of each revolution and
the lifting rollers 4 & 5 are so geared with the depressing rollers 18 & 19 that
they act on the stem 2 alternately, and the moment 4 & 5 cease to lift, 18 & 19
begin to depress.
The bearings 8, 10, 22 & 23 may conveniently be drawn together by spiral
springs 24 & 25, stops being provided on the framework (not shown) in which
the bearings 8, 10, 22, & 23 slide, to prevent the rollers moving near enough to
the stem 2 for the cut away portion of the rollers to come in contact therewith.
A number of such stamps (for crushing quartz, etc.) may be mounted in one
framework side by side, and if the stems 2 are round instead of flat the rollers
may be turned to suit this section.
In order to cause these stamps to revolve to prevent uneven wear of the tups or
dies, a device is shown consisting of a worm 47 gearing into a worm wheel 48 sliding
on the stem 2 and transmitting its slow rotary motion to same by a feather or key
way. The worm 47 receives an intermittent rotary motion by means of the ratchet
wheel 49 and detent 50 pendant from the lower arm of the bell crank lever 51, which
may be moved by a tappet 2 fixed to the stem 2.
From the foregoing description the construction and action of a hammer con-
structed according to my invention will be clear, but I will now describe the mode of
working same.
On moving the handle 27 downwards the eccentric bushes which carry the shaft 7
will be partly rotated and will cause the shaft 7 to move slightly towards the stem 2
bringing the revolving roller 5 into contact therewith and pressing the stem against
the roller 4 which is also revolving if driven by gearing from the shaft 20 which is
rotated by a pulley, shown by a circle and arrow in Fig. 1.
The stem 2 being thus gripped between two upward moving surfaces will be lifted.
On slightly releiving the pressure on the handle 27, the weight of the stem and tup
will cause them to fall by gravity.
If, however, the handle 27 is briskly raised before the stem has time to fall, then
the top rollers 18 & 19 will be caused to grip the stem 2 in a similar manner to 4 & 5,
but as the surfaces of 18 & 19 which thus grip the stem 2. are revolving at any desired
speed in a downward direction, they will impart a high velocity to the stem by
friction and the blow delivered by the tup will be proportionately increased.

page_text: An automatic stop to prevent the stem being raised too high can be arranged to be
caught by a tappet fixed to the stem and actuating a lever pivoted to the frame 1 and
connected either rigidly or by a spring to the rod 26 so as to bring the rollers 4 & 5
out of contact, and the rollers 18 & 19 into contact, to check and reverse the motion
of the stem.
"
The eccentric bushes 8 & 22 may be constructed so as to be capable of adjustment
from time to time by hand to bring the rollers into a proper position relative to
the stem, but it will be clear that these bushes may be moved simultaneously witli
10 & 23 by connecting them across to each other by rods and links' or 'toothed
segments or other similar devices, so that both rollers 4 & 5 or 18 & 19 will be
moved towards or away from the stem 2.
Instead of arranging both the rollers & 19, which are moved towards the stem by
the lever 27 on the same side of the stem, it will sometimes be convenient to move
the roller 5 and the roller 18 by the lever 27 leaving the rollers 4 & 19 stationary,
though capable of adjustment from time to time as the stem 2 wears.
By this arrangement the stem would be pressed over against the roller 4 to lift
the tup, and against 19 to depress it which could be done by reason of its length
and slight flexibility.
The effect of this would be to free the stem from possible contact with two
surfaces revolving in opposite directions at one and the same time, which might
tend to check its movement and waste power.
The relative velocity of the surfaces of the lifting and depressing rollers may be
varied as desired either by using cone pulleys on their spindles, or by varying the
ratio of the gearing say by driving the top rollers on one side, from the one below it,
and the bottom roller on the other side from the one above it by gearing having the
desired ratio, so as to keep the surface velocity of each roller of each pair the same.
Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed I declare that what. I
claim is :-
1st. In a power hammer, wherein the head or tup a is raised by frictional contact
against revolving or moving surfaces, the use, in combination therewith, of other
revolving or moving surfaces 18 & 19 moving in an opposite direction to the lifting
surfaces 4 & 5, and capable of being brought into contact with the head or a stem 2
attached thereto, for the purpose of imparting a greater velocity in a given fall, to the
head or stem than it would attain by the action of gravity alone, substantially as
set forth.
2nd. In a hammer or stamp of the kind hereinbefore described & in reference to
Figs. 4, 5, 6 & 7. the use of a spring connection between the rollers and their
driving shafts, substantially as and for the purpose described.
3rd. In a hammer or stamp of the kind hereinbefore described and in reference
to Fig. 11, the use of friction rollers for lifting and depressing the stamp, having
a portion or portions of their friction surfaces cut away to obtain an intermittent
action, the lifting and depressing rollers being so geared together as to come
alternately into action in the manner described.
4th. A hammer or stamp constructed, arranged, and operating in the manner
described either with reference to Figs. 1, 2 & 3 or Fig. 11.
Dated this 5th day of Fube 1880
F. BOSSHARDT & Co.,
4, Corporation Street, Manchester,
Agents to Applicant.