Electric Percussive Tool.
Year: 1893

page_text: Date of Application, 2nd Feb., 1893-Accepted, 7th Oct., 1893
COMPLETE SPECIFICATION.
Electric Percussive Tool.
1, GEORGE HENRY WILLIAMS, Gentleman, resident of 14th Street and
9th Avenue, New York, in New York County and State of New York, United
States of Amerien, do hereby declare the nature of this invention and in what
manner the samo is to be performed, to be particularly duscribed and ascertained
in and by the following statement:—
My invention relates to improvements in an "electric tool," and consists in
the novel arrangement of parts as will be more fully hereinafter described and
set forth in the claims.
The object of iny invention is to construct a tool having a reciprocating plunger,
actuated by an electric current, and adapted to take the place of the methods now
employed in operating chisels, drills, and other analogous instruments, used in
Sculpturing, engraving, repoussé work, and in fact any and all kinds of artistic and
ornamental work, as well as boilor calking, boiler riveting, stone cutting and
drilling, and coal and other mining.
For many different kinds of work, different sizes and forms of tools would be
necessary, but the principle involved would be the same in all.
The tool is especially adapted for use by sculptors and others in whose cccupation
the carving of marble, stone and metals enter largely, and it dispenses with the
slow and laborious hand work hitherto experienced.
In a tool for such use, the stroke can be made to vary from one-eighth of
an inch to one inch, and at a speed ranging from three hundred to six hundred
strokes per minute..
Practical experience with the use of the tool has shown that it is particularly
useful for the carving of letters or other figurea where it is necessary to follow
accurately straight or curved lines.
To give an idea of the herein described tool I will say that its weight does not
exceed six pounds, and as no movement of the same by the hand or arm is necessary,
it will be seen that the weight of the tool causes no inconvenience.
The current for the operation of the tool may be derived from cells of storage
batteries or from a line wire, as is most convenient to the user. In case the
device were applied to the drilling of large stones, a larger construction would be
necessary, this feature being controlled by the necessities of the occasion.
In the drawings:
Fig. 1 is a vertical detail elevation of my complete invention.
Fig. 2 is a vertical detail sectional view taken on a line B—B in Fig. 3.
Fig. 3 is a vertical detail sectional view taken on a line A--A in Fig. 1.
Fig. 4 is a diagrammatic view tracing the passage of the current to and from
the tool.
Fig. 5 is a top plan view of a supporting device used to elevate the electric tool
over a piece of work and at the samo time allowing its adjustment.
Fig. 6 is an end elevation of the adjustable support.
Fig. 7 in a detail sectional view with parts broken away of the supporting
device.
Fig. 8 is a detail view of a portion of a set-screw which is used to determine
the length of movement of the reciprocatory plunger, and showing the securance
therein of a tip of insulation material.
Fig. 9 is a detail view of the lower end of the shaft and its hearing in the
lower cap and showing the means for revolving said shaft when it is reciprocated.

page_text: .
ends and provided with caps 3 and 4, the cap 3 fitting upon the upper end of same
and the cap 4 upon the lower end of said shell.
The cap 3 consists of a hollow shell having the upper end 5 closed, the said end
being surmounted by a centrally located and upwardly projecting portion 6,
circular in cross-section and provided with a vertical 'interiorly sorew-threaded
bore 7.
The inner periphery of the shell-cap.3 is provided, near the lower end with an
annular cut-out portion 8, which is, adapted to fit over the upper end of the
shell 2.
Scrows 9 secure said cap 3 upon the shell 2 and prevent any movement of the
same.
The lower end of tho shell 2 is provided with the cap 4 as hereinbefore stated.
Said cap
4 is narrower than the cap 3 and adapted to set entirely over the
shell 2 with the end 10 of said cap 4 against the lower edge of its integral parts.
Projecting downwardly from said end 10 and from the center of same is a
portion 11, circular in cross-section and provided with a bore 12 and a countor
bore 13, said counter bore 13 extending throughout about two-thirds of the length
of the projection 11 and the thickness of the plate 10.
The cap 4 is secured upon the shell by means of screws 14 and said cap 4 in
conjunction with the shell 2 and cap 3 form what may be substantially called a
hollow tubular closed chamber.
The magnet core 15 consists of a tubular central portion having upon each end
an annular plate or projection 16 which are of the same diameter as the interior
of the shell 2 and into which said magnet core 15 is adapted to fit.
This construction of the core makes what is substantially a spool, the wire 17
being wound upon the tubular portion 15 and between the plates 16.
The magnet core is held in the casing 2 by screws 18 which project through
the plate 10 forming the end of the cap 4 and engaging in the lower end plate 16.
The inner end of the wire 17 is secured to the plate 16 at the upper end of the
zoil, the said ioner end 19 being insulated from contact by any of the balance of
the wire in order to carry out the function of the magnet, as is well known.in such
constructions.
The outer end 20 of said wires 17 is covered by additional insulation, consisting
of a piece of tubing 21, which protects the wire from the coil through an opening
in the shell 2.
After leaving said shell 2 it passes upwardly and is held in a bracket arm 22
secured upon the upwardly projecting portion 6 upon the end of the cap 4.
The other wire necessary for the conducting of the current to the coil is
secured under the head of a bolt 23 which passes through an opening in the top 5
of the cap 4 at one side of the same and which is insulated from said cap by
plates 24 above and below said plates 6 and an insulation tubing 25 upon the
bolt 23 where it passes through said end plate 5.
Secured upon the lower end of said bolt 23 and projecting inwardly to the
center of the chamber 26 formed between the upper plate 16 of the magnet and
the end plate 5, is a spring plate 27 provided upon its upper and lower sides with
platinum contact plates.
The spring plate 27 is held upon said bolt aud against the lower block of
insulation 24 by a nut 28.
Adapted to be vertically reciprocated in the bore 29 within the shell 15 of the
core is a shaft 30 upon the upper end of which is secured a circular disk or plate 31
upon the under side of which is secured a plate of yielding insulating material 32,
which serves to provent the jarring movement of the parts and also acts as an
insulator between the plate 31 and the plate 16.
The disk 31 is of less diameter than the interior of the cap 3 and is adapted to
bo reciprocated in the chamber 26.
The shaft 30 is hollow throughout a little over one-half of the upper portion of
its length, in which is located an interior shaft 33, which projects through' and

page_text: above the disk 31 and is held by a nut 34 screwed upon the upper end thereof and
above said disk 31.
A portion of said shaft 33 below the tubular portion 30 is of the same diameter
as the said tubular portion, said enlarged portion 35 terminating in what might be
termed a downwardly extending counter-shaft 36.
The shaft 33, nut 34, enlarged portion 35 and counter-shaft 36 are all made of
brass or some equally good electrical conductor, while the tubular shell 30 and
disk 31 are made of soft iron.
A coil spring 37 is located upon the counter-shaft 36 and between the portion 35
and the end of the counter-bore 12 and necessarily determines the normal position
of the shaft and disk forming a plunger, said normal position being with the upper
end of said shaft in contact with the spring plate 27.
A small block 38 of platinum is secured in the upper end of the shaft 33 and
engages the platinum contact plate upon the lower side of the spring plate.
The upward movement of the plunger is limited by an adjustable set screw 39
having thumb nut 40 mpon its upper end and a jamb out 41 upon its length to
determine its stationary position as desired, said nut 41 being jambed against tho
portion 6 upon the plate 5.
The downward adjustment of the screw 39 necessarily limits the upward
movement of the plunger.
As it engages the spring plate 27 and forces the same downwardly the force
of the movement of said plunger, being determined by space which it has to
reciprocate in, said space being between the plate 16 and the spring plate 27 as
held by the screw 39.
As seen in Fig. 8 the lower end of the screw 39 is provided with a projecting
tip 42 made of yielding insulating material and counter-sunk into the end of said.
Borew.
The wire 43 which is secured under the head of the bolt 23 allows the passage
of the current through said bolt into the spring plate 27, and from thence into the
shaft 33.
The current passing through these parts energizes the coil as the current passes
from the shaft into the tubular shell 30 and the end plates 16, the inner end of the
wire 17 being secured to the upper plate 16.
The energizing of the coil causes the same to act as a magnet and draws down
the shaft and necessarily the disk 31 upon the upper end thereof.
This operation compresses the spring 37 and the instant that the contact is
broken between the upper end of the shaft 33 and the spring plate 27, said spring
forces the plunger upwardly again into contact with said plate.
The above operation is repeated as long as the current is allowed in the tool,
but said current can be out out at any time by means of the switch 44.
In Figs. 5, 6 and 7 is shown a supporting construction by means of which the
larger sizes of tools are held in position over the work upon which it is used and
is especially designed for use when drilling large blocks of material, for boiler
work, &c.
It comprises two sets of inverted V-shaped standards 45 connected by
longitudinal pieces 46, the upper ends of said brackets providing bearings 47 in
which a longitudinal shaft 48 is adapted to both revolve and reciprocate as desired.
The shaft 48 is provided intermediate of its length with a transverse bore 49,
with a bushing 50 located therein which acts as a bearing for an eye-bolt 51 the
upper end of which provides a bearing 52 for a shaft 53 located at right angles
with the shaft 48 but which may be changed to any angle with said shaft.
A washer 54 is secured to the upper end of the bushing 50 and a washer 55 is
secured under the head of the eye-bolt 61 and a nut 56 is located on the lower".
screw-threaded end of the bolt 51 to prevent its withdrawal from its bearings.
A set-screw 57 projects through the head of the bolt 51 and is used in case it is
desired to hold the shaft 53 in a stationary position.
One end of said shaft 53 is provided with a balance weight 58 while the

page_text: -
opposite end of same has two projecting arms 59, which are secured to the
shell 2 in such a manner that the complete electric tool is oscillatory.
It will be seen from the above description and by reference to the drawings,
that the shaft 48 can be moved in its bearings 47 in a longitudinal horizontal
manner and can be ravolved as well, while the shaft 53 can be moved longitudinally
through its bearing 52, can be turned at any angle in a horizontal manner and
similarly in a vertical manner.
The adjustment of the set-screw 39 regulates the length of movemont of the
reciprocatory plunger and the insulation tip upon the lower end of said screw
prevents the current from passing into the cap 3, and thus it is only possible for
the current to pass into the coil through the plate 16 to which the inner end of
the wire is secured, and in which the current is transmitted by the engagement
of the shaft with the central portion 30 of the core.
In Fig. 9, the counter shaft 36 is provided with a zig-zag channel or groove 6(),
which extends around the entire periphery of the shaft 36.
A spring-controlled pin 61 normally engages in said groove 60, and with the
downward movement of the shaft, said groove travels over said piu, the pin being at
the uppermost point of one of the angles formed by the zig-zag, and when the
shaft reciprocates upwardly, the pin engages in the next branch of the zig-zag
groove and turns the shaft a prescribed distance, each reciprocatory movement of
the shaft thus turning the same around.
The object of this construction is to equalize. the wear upon the lower end of
the shaft, which acts as a hammer, striking a chisel which is held within the
counter-bore 13.
Having now particularly described and ascertained the nature of said inven
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. An improved electric tool having a plunger adapted to be reciprocated by
the energizing of a magnet coil, through which said plunger operates, substantially
as set forth.
2. An improved electric tool having a reciprocatory plunger comprising a rod
surmounted by a circular disk, and an adjustable set-screw located in the top of
the shell, and the adjustment of which determines the length of stroke of snid
reciprocatory plunger, substantially as set forth.
3. An improved electric tool having a plunger comprising a rod or shaft, a
portion of said shaft tubular and encasing an interior shaft made of brass or some
equally conductive material, the remaining portion of the length of said shaft,
made with and of the same material as said brass shaft, and a spring located over
a counter shaft upon the outer end of the plunger shaft aud adapted to keep the
plunger in a normal position against the upper end of the tool casing, substantially
as set forth.
4. An improved electric tool having a reciprocatory plunger, comprising a rod
or shaft surmounted by a circular disk hold thereon by a nut adjusted upon the
upper end of a projecting interior shaft made of brass or some,equally conductive
material, and said plunger rod above the disk adapted to engage a spring-plate
insulated from the shell casing and secured upon a bolt, leading outside of said
casing, and through which an electrical conductor is secured, and a spring located
upon a counter-shaft comprising the lower and of said plunger rod, and adapted to
keep said plunger in contact with said plate, substantially as set forth.
5. An improved electric tool having a casing comprising a cylindrical shell
open
nt both ends and normally closed by removable caps, a magnet core located within
said cylindrical shell and normally secured to the lower cap by screws, the core of
said magnet comprising a tubular portion with annular plates upon both ends, the
inuer end of the wire upon said coil secured, to the upper end plate and the other
end of said magnet wire passing through an opening in said shell and, insulated
therefrom, substantially as, set forth.

page_text: 6. An improved electric tool, having a casing comprising a cylindrical portion
adapted to receive the magnet coil, a lower end cap having a downwardly projecting
portion provided with a boro and counter-bore, an upper end cap secured to said shell
and having an upwardly extending portion provided with a scrow-threaded aperture,
through which a screw-threaded set-screw is adapted to be reciprocated, a jamb nut
located upon said set-screw and adapted to be jambed against said upwardly projecting
portion to determine the desired position of said set-screw, the lower end of said
set-screw provided with a projecting yielding insulation tip adapted to engage a
spring contact plate, secured to and insulated from the upper end cap, and a
downward or upward adjustment of said set-screw adapted to determine the length
of stroke of a reciprocatory plunger located within the casing, substantially as
set forth.
7. An improved electric tool having a casing comprising a cylindrical shell 2, an
upper end cap 3 normally secured to said shell 2 by screws 9, the upper end 5 of
the said cap 3 having an upwardly projecting portion 6 provided with a vertically
interior sorew-thronded opening 7, a set-screw 39 adapted to be reciprocated in
said opening 7, a jamb nut 41 adapted to determine the position of said set-screw
by the jambing of same against the projection 6, a magnet core 15 located in the
shell 2, a lower end cap 4 secured to said shell 2 by means of screws 14, a
downwardly depending central portion 11 upon said cap 4, a bore 12 in said
projection 11 terminating in a counter bore 13, a reciprocatory plunger comprising
a rod, the tubular portion 30 of which encases an interior shaft 33 made of brass
or of some equally conductive material, upon the upper end of which is secured a
disk 31 provided on its under side with an insulated plate 32 made of some yielding
material the lower portion of the plunger rod smaller than the main portion of its
length, a coil spring 37 located upon said portion 36 and in the bore 12, the
tendency of said spring to keep said plunger upwardly in a chamber 26 formed
between the upper end of the mngnet and the top plate 5 of the cap 3, a spring
plate 27 secured to and insulated from said plate 5, a wire 43 connecting with a
bolt 23 passing through and insulated from the plate 5 and scouring the spring
plate 27 and the downward adjustment of the set-scrow 39 adapted to detormine
the length of stroke of said reciprocatory plunger, the lower end of said set-screw
provided with a yielding tip of insulation material, substantially as set forth.
8. An improved adjustable support for electric tools comprising two inverted
V-shaped standards 45, connected by lougitudinal pieces 46, said pieces 46
connecting two pairs of said standards 45, bearings 47 provided by the upper ends of
said standards for a shaft 48, said shaft 48 revoluble in said bearings and horizontally
adjustable in same, said shaft 48 having a transverse opening 49, a bushing 50
located therein, a cap plate 54 to said bushing, an eye-bolt 51 adjustable in said
bushing and held therein by a nut 56, a boaring 52 provided in the hoad of said
bolt 51 for a horizontal adjustablo shaft 53, a balance weight 58 upon one end of
said shaft, and the opposite end of said shaft providing a holder for the electric
tool, and said shaft 53 horizontally adjustable at any angle, vertically adjustable
at any angle by the revolving of the shaft 48 and reciprocatory within the
bearing 52, substantially as set forth.
9. An improved electric tool having a shaft comprising a portion of a plunger,
reciprocatory within the magnet said shaft having a downwardly projecting counter
shaft provided near its lower end and in its periphery with a zig-zag groove 60
adapted to be engaged by a spring-controlled pin 61, located in the projection upon
the lower cap, and a reciprocatory movement of said shaft adapted by the
engagement of said pin in said groove to turn said shaft with each movement,
substantially as set forth.
1
11
CL009
ALLISON BROS.,
Agents for the Applicant.