First the Construction and use of Springs for pistons of Steam engines and for other various purposes substantially as herein before described and illustrated Second
Year: 1881

page_text: No text detected.
"
#
We ARTHUR THOMAS ALLEN of Queens Road Finsbury Park in the County of
Middlesex and HENRY CAVILL of Sheffield in the County of York seek leave to
amend the Specification of Letters Patent, No. 1405 of 1881, as shown in red ink
in the copy of the original Specification hereunto annexed by striking out on
page 3, lines 3, 4 and 5 the words following that is to say "First the Construction
and use of Springs for pistons of Steam engines and for other various purposes
substantially as herein before described and illustrated Second"
Our reasons for making this amendment are as follows-That we are advised
that the above words which constitute the first claim in the original Specification
may be construed so as to claim more than the Patentee intended to claim at the
time when he filed his Specification.
We are the registered assignees in moiety of the said Letters Patent.
In the Matter of Letters Patent granted to David Blackadder on the 30th March
1881 No. 1405.
I hereby grant leave to Mess" Allen & Cavill (the Assignees of the said Letters
Patent) to amend the Specification filed in pursuance of the said Letters Patent in
the manner proposed.

page_text: PROVISIONAL SPECIFICATION left by the said David Blackadder at the
Office of the Commissioners of Patents on the 30th March 1881.
DAVID BLACKADDER of Sheffield in the County of York, Smith
MENTS IN THE CONSTRUCTION OF SPRINGS FOR PISTONS."
"IMPROVE-
My Invention relates to improvements in the constructions of springs for pistons
of steam and other motive power engines, steam bammers, pumps, blowing engines
and for other similar purposes, and particularly to such springs as are made from
rods or wire of steel, coiled or otherwise shaped; the object of my Invention being
to produce a spring having a direct elastic vertical action, (which is a great
desideratum in pistons for steam hammers) as well as the usual expanding action,
and to avoid some of the defects of the ordinary method of constructing such springs,
and it consists chiefly in the manner of coiling the wire or rods, and in the arrange-
ment of the said coils.
•
In carrying out my Invention I take a rod, or a piece of wire of a suitable length,
and form with it, at equal distances from each other, a series of coils, or spiral springs,
each coil or spring being of equal height and connected by the continuation of the
rod or wire, such connecting piece being straight or curved as may be preferred.
When a sufficient length is thus coiled, the whole length is curved or bent into a
circle of the desired diameter, the ends being secured together in any suitable
manner. The spring is hardened and tempered in the usual way..

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said David Blackadder in the Great Seal Patent Office on the
28th September 1881.
DAVID BLACKADDER of Sheffield in the County of York
IN THE CONSTRUCTION OF SPRINGS FOR PISTONS."
IMPROVEMENTS
My Invention relates to improvements in the construction of springs for pistons
of steam engines, steam hammers, and for pistons used for other similar purposes,
and particularly to such springs as are made from rods or wire of suitable metallic
substance, coiled or otherwise shaped.
The object of my Invention being to produce a spring having a direct elastic
vertical action, (which is a great desideratum in steam hammers) as well as the
usual expanding action, and to avoid some of the defects of the ordinary methods
of constructing such springs-and it consists chiefly in the method of coiling or
bending the wire (or rods) and in the arrangement of the said coils or bends.
In carrying out my Invention as applied to the pistons of steam engines, of
ordinary construction; that is, having a block and a removeable cover, I take a
length of wire, or a rod, by preference of steel and of suitable diameter, and form
with it, at equal distances apart, a series of coils, bends, or spiral springs, each coil
having a corresponding number of turns or rings. Each coil is connected by the
continuation of the rod or wire, such connecting portion of the rod or wire being
straight or curved; as inay be preferred-Each coil is turned or bent in the opposite
direction to its neighbour-alternately right and left hand-and when a sufficient
length is thus coi!e or bent, it is formed into a circle of the required diameter, the
ends being secured together by any suitable device, but I prefer to secure or couple
them by using a coupling.hich may be made from the same wire as that used for
the spring, formed into an oval shaped coil to receive both ends of the wire and
thus forming an elastic joint. By using a longer coupling the spring may be
expanded and vice versa. I do not bind myself to the number or size of the coils
in a spring of a given diameter, nor to the strength of the material used, as all these
may be varied to suit different purposes.
And in order that my Invention may be fully understood I will now refer to the
annexed Sheet of Drawings and to the letters and figures marked thereon, the same
letters of reference indicating corresponding parts in all the Figures.
Fig. 1 represents a piston shown in cross section, and fitted with my improved
piston spring consisting of circular coils alternately coiled to the right and left
hand, A, A are the coils, B, B the continuation of the wire connecting the coils
C, C, are the piston rings, recessed to receive the spring.
Fig. 2, represents a plan of said spring-with side view of a treble coil, and also of
a single coil, D is the coupling.
Fig. 3, represents a modification of my Invention-the coils being arranged in a
different manner-namely horizontal instead of vertical.-The side views show the
arrangement of a spring with three coils, and also one with one coil only.
Fig, 4 represents a spring adapted for use in contracted spaces in which the coils
or bends of the wire being flat instead of round, there is no projection beyond the
thickness of the wire itself.
A is the coil or bend, B and B' are the continuation wires.
Having now described and particularly ascertained the manner in which my said
Invention may be carried into practice, I would observe that I have not illustrated

page_text: on the Sheet of Drawings all the modifications that may be made in the construc-
tion of springs according to my Invention, but what I consider to be novel and
original and therefore claim as the Invention secured to me by the hereinbefore in
part recited Letters Patent is―.
First, The construction, and use of springs for pistons of steam engines and for
other various purposes, substantially as hereinbefore described and illustrated.
Second, The construction and use of compound springs for pistons, composed of
a series of vertical spiral springs of any desired number of coils connected together
by the continuation of the wire of which the spring is composed, the said coils being
coiled to the right and left hand alternately.
In witness whereof I the said David Blackadder have hereunto set my
hand and seal this 27th day of September in the year of our Lord; One
thousand eight hundred and eighty one.
DAVID BLACKADDER: (LS)