Improvements in Power Hammers.
Year: 1892

page_text: Date of Application, 23rd Feb., 1892
Complete Specification Left, 22nd Nov., 1892--Accepted, 14th Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in Power Hammers.
A communication by ALEXANDER BEAUDRY, of 70, Kilby Street, in the City of
Boston and State of Massachusetts, United States of America, Manufacturer
of Power Hammers.
I, WILLIAM PHILLIPS THOMPSON, F.C.S. M.I.M.E. of the Agency for
Foreign Patent Solicitors, 6, Lord Street, Liverpool and 6, Bank Street,
Manchester both in the County of Lancaster and 323, High Holborn in the County
of Middlesex, Civil Engineer, do hereby declare the nature of this invention to
be as follows:
This invention relates to power hammers having facilities for varying the force
of the blow to suit the work in hand, and the object of the invention is to produce
a cheap and efficient hammer of this class which will occupy a limited space and
have good wearing qualities.
In carrying out the invention, a frame of cast iron is constructed having a vertical
guide for the hammer-head arranged over the portion of the frame in which the
anvil is set. Preferably the hammer-head is cylindrical, and it has a recess in its
middle in which are placed cushion springs, usually of rubber, which embrace the
end of the helve from above and below, a pin, preferably of wood, passing down
through a bore in the axis of the head and through said springs and helve.
Vibration is imparted to the helve and head by mechanism which will be
described.
'
In the base of the frame is mounted a shaft on which is a pulley to receive a
belt for driving the shaft, and on the shaft is fixed a crank, within the hollow of
the frame, which crank is coupled by a connecting rod to a lower arm or link
pivoted in the frame at its rear end and projecting forward toward the hammer-
head. The free, forward end of this lower arm or link is coupled to the free, rear
end of a similar upper arm or link, by an upright tie-bar. This upper link is
pivoted to the frame at its front end, and projects rearwardly, and the free ends of
the two links are in about the same vertical plane, so that the tie-bar, pivotally
connected to these free ends of the links, stands upright.
These three elements, namely, the two links and the tie-bar, form a sort of jointed
frame which is moved up and down by the crank and connecting-rod, the arms
turning about their pivots in the frame.
The middle part of the tie-bar stands, at mid-stroke, on about the same level as
the middle of the hammer-head, and the rear end of the helve is connected to said
tie-bar at this middle point. This rear end of the helve is widened vertically by
lateral branches, and the widened end is made convex on its face where it bears
against the face of the tie-bar.
The connection is made by two bolts which pass through the respective lateral
branches on the helve and through the tie-bar, a cushion-spring, usually of rubber
being placed between the rear face of the tie-bar and the nut and washer on each of
the bolts. To take the strain off from the bolts, a screw or pin with a rounded end
is driven through the tie-bar from the back, and midway, measured vertically,
between the bolts and the rounded end of this screw or pin enters a shallow recess
in the convex face of the helve.
When the hammer is set in motion, the tie-bar carrying the helve, moves rapidly
up and down, and the cushion springs at both extremities of the helve together with
the peculiar inotion imparted to the helve by reason of the two links swinging about
their centres, imparts to the hammer-head a stroke similar to that of a hammer in
the hand of the smith, momentum entering into it largely as an element.

page_text: The force of the blow is governed, or may be governed, in the usual manner with
hammers of this class, namely, with a treadle or lever which applies an idler to the
driving belt so as to tighten or slacken it.
In order to get the best effect from the hammer-head, it and its attached parts
are counter-balanced in whole or in part by a spring; and this spring is preferably
applied to a prolongation of the lower link or arm (to which the connecting-rod is
coupled), said prolongation extending rearwardly of the point where said link is
pivoted to the frame. This spring is attached at its lower end to the frame or to
some fixed point.
It is preferred to make the crank-pin adjustable so that the throw of the crank 1
may be varied if desired.
Dated this 22nd day of February 1892.
WM. P. THOMPSON & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Power Hammers.
A communication by ALEXANDER BEAUDRY, of 70, Kilby Street, Boston, in the
County of Suffolk and State of Massachusetts, U.S.A., Manufacturer of
Power Hammers.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for
Foreign Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Man-
chester, both in the County of Lancaster, and 323, High Holborn, in the County of
Middlesex, Civil 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 :-
This invention relates to improvements in power hammers having facilities for
varying the force of the blow to suit the work in hand, and the object of the inven-
tion is to produce a cheap and efficient hammer of this class which will occupy a
limited space and have good wearing qualities.
In the accompanying drawings, which illustrate the present invention→
Figure is a sectional side elevation of the hammer, the hammer-frame being
substantially in mid-section at its upper part to better disclose the mechanism
which actuates the hammer head. The upper part of the hammer head is also in
section.
Fig. 2 is a rear elevation of the hammer.
Fig. 3 is a plan of the hammer.
Fig. 4 is a sectional, detail view of the crank-wheel and pin.
The frame A of the hammer is constructed by preference, of cast iron, and it
may be made in one piece, or integral. A' is the portion of the frame in which
the anvil B is mounted, and A2 is the over hanging portion of the frame in which
the hammer-head C, plays up and down over the anvil in suitable guides. The
other, or main part of the frame is substantially hollow, and in this hollow is
mounted the mechanism by which the proper motion is imparted to the hammer-
head. D is the main shaft, mounted at the base portion of frame A, in a bracket A³.
thereon, and E is a driving pulley keyed on the said shaft. On the shaft D, within
the hollow of the frame A, is a crank-wheel F, from which a reciprocating move-
ment is imparted to the hammer-head through the medium of mechanism, which
will now be described.
G is an upper link, pivotally mounted aty, in the frame on a transverse pin,
and G', is a similar lower link, pivoted at g', in the frame, in a manner similar to
link G. The upper link is pivoted at its front end, and the lower link is pivoted
at its rear end. When in the intermediate position seen in Fig. 1, the free ends of
these links will be, or may be, in the same vertical plane when seen in side elevation.
H is an upright tie-bar, coupled at its upper end to the free end of the link G, and

page_text: at its lower end to the free end of link G'. The lower link is coupled to the
crank-pin f, of the crank-wheel F, by a connecting-rod I. Thus, when the main
shaft is rotated, the rod I imparts a vibrating up and down motion to the
tie-bar H.
J is the hammer-arm or helve. This arm plays in an aperture in the front of
the main frame, and its front end j, which is flattened and has a central aperture,
enters a hollow in the hammer-head C, where it is embraced, from above and below,
by rubber cushions, c, c, in the hollow of the hammer, and held in place by a pin c¹,
preferably of hard wood, which passes down through holes in the hammer-head,
in the cushions c, c, and in the end of the helve. At its other or rear end, the
helve has a T-shaped head j", which is parti-circular or convex, where it bears on
the front, upright face of the tie-bar H, and is provided, at the two extremities
with eyes or pairs of apertured lugs, whereby it is loosely coupled, by pins", to
two eye-bolts, h, h, which play loosely through apertures in the tie-bar H, and have
nuts and washers on their rear ends back of the bar H. On each eye-bolt h,
between the bar H, and the nut or washer on the eye-bolt, is a rubber cushion h'.
Preferably the bar H is provided with recesses in its rear face to receive the
cushions h', and provide each eye-bolt with cup-washer 2, to take over the outer
end of the cushion and receive the chafing and wear from the nut, ³, on the
bolt. By tightening up the nuts, the desired tension of the cushions ¹, may be
attained.
When the shaft D is set in motion, the tie-bar H receives a rapid up and down
reciprocating movement, modified by the swing of the links G and G' about their
pivots. This variation from the vertical by the bar Has it moves to and fro is
imparted to the hammer-helve J, and the movements of this helve will be further
modified by the cushions ¹, at the back of bar H, and the cushions in the hollow
of the hammer-head.
The convex face of the head j¹ of the helve rolls or rocks more or less on the
face of the bar H, during the operations of the hammer, thus overcoming to some
extent the inertia of the hammer-head at the beginning of the return stroke by the
resiliency of the cushions /'.
To relieve the lateral (vertical) strain on the eye-bolts which secure the helve to
the bar H, it is preferred to pass a stud, &, through the bar H, from the back, about
midway between the eye-bolts, and allow its rounded end to loosely engage a corre-
sponding recess in the convex face of the head j, of the helve. This pin takes the
weight of the parts to some degree off from the eye-bolts.
:
To counter balance the weight of the hammer-head and helve, and put the
mechanism more nearly in equilibrium, a counter-spring is provided. To a rear
prolongation of the link G', back of the pivot y', is coupled a spring casing, L,
represented as partly broken away in Fig. 1. In this casing is placed a spiral
spring, M, through which passes a spring-rod N, which is adjustably coupled at its
lower extremity to a bracket n on the frame A. At its upper, or inner end this
rod N has a head n', which takes over the upper end of the compression spring M.
A nut n², on the lower end of the rod N allows the spring to be put under any
tension desired.
By thus counterbalancing the head of the hammer the use of a fly-wheel is
avoided and the stopping of the hammer is effected almost instantly by means of a
brake. By preference an ordinary treadle-brake is employed, the shoe of which
bears on the broader face of the pulley rim, but it has not been deemed necessary
to illustrate the brake in the drawing as it possesses no novel features. The
counterbalancing spring may be of rubber, as it is a compression spring and the
amount of compression, during the descent of the hammer will not usually be more
than five-eighths of an inch.
The part A' of the frame in which the anvil is set may and preferably will be,
cast separately from the main portion A, and be bolted or screwed firmly thereto.
The hammer-head C is prevented from turning axially in its guides, it being
cylindrical in form,-by means of a groove extending longitudinally of the head,
1

page_text: and a spline m (seen in Fig. 3) which engages the groove in the hammer-head and
a groove or key-way in the part A² of the frame in which the hammer-head is
mounted. The spline m is held in place by a suitable screw or screws o.
Cushion springs of wire or of metal and rubber combined, may be employed in
lieu of the rubber springs shown. It will be obvious also, that an eccentric for
operating the hammer may be employed in lieu of the crank described.
As herein shown, the crank-pin f, is in the form of a stud projecting from a dove-
tail block f which is mounted in a radial dovetail groove in the face of the crank-
wheel F and has a nut and washer on its outer end. On the crank-pin is a
sleeve, which is clamped end wise between the face of the wheel F and the nut.
This serves to clamp the block f' wherever it may be set. The end of the
connecting-rod I turns about the sleeve f. This construction enables the throw of
the crank to be varied within limits by merely loosening the nut on the crank-
pin and shifting the block f'. Fig. 4 is a sectional view which clearly illustrates
this construction.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. In a power-hammer, the combination with a frame, a hammer-head mounted
to play in guides, and a main power shaft, and crank, of the links G, G¹, pivotally
mounted in the frame, the tie-bar H, coupled at its respective ends to the free ends
of said links, the connecting-rod which couples the one of said links to the crank,
and the helve J, having a cushioned connection with the hammer-head at one end
and a cushioned connection with the tie-bar H at its other end.
2. In a power-hammer, the combination with a frame, a hammer-head mounted
to play in guides therein, a power shaft, and a crank on said shaft, of the upper
link G, pivotally mounted at its front end in said frame, the lower link G¹ pivotally
mounted at its rear end in said frame, the upright tie-bar H, coupled at its
respective ends to the free ends of said links, the connecting-rod, which couples the
crank to the lower link G', the helve J, having its front end embraced between
cushions in the hollow of the hammer-head, the said cushions, the tie-bolts, which
connect the convex, T-shaped head of the helve to the bar H the cushions on said
tie-bolts, and the counter-spring for the hammer-head and helve.
3. In a power-hammer, the combination with a frame a hammer-head which is
mounted in vertical guides therein, an upright bar H, connected to the frame by
links, the said links, and means for imparting to said bar an up and down motion,
of a helve J, provided with a convex, T-shaped rear end having apertures at its
extremity, eye-bolts which couple the helve to the bar H, and hold it firmly up
thereto, the elastic cushions on said eye-bolts, the stud k in the bar H, which
engages a recess in the convex face of the helve, the cushions in the hollow of the
hammer-head and embracing the end of the helve, and the pin which couples
together the helve, hammer-head and cushions.
Dated this 21st day of November 1892.
WM. P. THOMPSON & Co.,
Agents for the Applicant.