Year: 1896

page_text: Date of Application (in United Kingdom), 13th July, 1896
Complete Specification Left, 13th July, 1896-Accepted, 12th Dec., 1896
I, CHARLES TUCKFIELD residing at Albany, in the Colony of Western
Australia, 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 has for its object the construction of an engine whose essential
feature is the peculiar means devised for the employment of a continuously
revolving piston both during its backward and forward longitudinal travel within
the cylinder by the well known motive power of steam or other pressure.
This result is obtained by the construction of a cylinder with a spiral or groove
formed in its inner surface or periphery, such spiral is continuous, that is it returns
to its apparent starting point within the cylinder and at similar pitch to its other
half portion, so that travelling in such groove from and returning to any one given
point in same a complete circle or circuit will be described within the cylinder. In
conjunction with this groove I use a piston having a button or equivalent
projection affixed to its rim or periphery, which button works or travels within or
engages with above mentioned groove, consequently as the piston is impelled
longitudinally, the button in impinging or pressing against the sides of the spiral
causes the piston to rotate, which rotation is maintained as long as the piston is
travelling either in a backwards or forwards direction.
In practice I prefer to construct a cylinder having a one half circuit groove,
that is to result in the pisten making half a revolution in its travel from end to
opposite end of the cylinder.
That part of the piston rod which is within the cylinder is of square section on
which the piston slides up and down, the piston rod being circular at its ends
which work in bearings mounted in or upon the cylinder covers the outer ends of
the piston red may carry a pulley for the transmission of power.
As an alternative construction I form a spiral groove on the periphery of the
piston and employ the fixed button projections, on the internal periphery of the
cylinder which gives a similar result as aforesaid.
To prevent any leakage of steam or other motive fluid or liquid through that
portion of the groove in which the fixed button is not actually engaged I form two
parallel and surrounding grooves or recesses in the rim of the piston one at each
side of the fixed button, these grooves carry loose buttons which slide easily
around the piston and travel in and along the spiral formed in the cylinder.
A clearance space is provided at each end of the cylinder for the purpose of

page_text: allowing freedom to the loose buttons whilst the fixed one is passing over the
apparent junctions or return points of the cylinder spiral.
The steam is introduced into the cylinder by means of an ordinary slide valve
or I may use a disc having slots which as said disc revolves, said slots open to
steam and exhaust ports in end of cylinder.
To dispense with the loose buttons the piston may be made double the length of
the groove, which latter is equivalent to that of the stroke, by this means the
piston at each end will alternately over-lap the spiral formation.
In order that my invention may be more clearly understood reference may be
made to the accompanying drawing which illustrates the essential part of same,
and in which :-
Figure 1. is a longitudinal section.
Figures 2 & 3 being views of the piston with its grooves.
In these drawings A is the cylinder formed with the spiral or groove B.
C. is the piston having the fixed button C2, grooves C3, and loose buttons C 4.
This piston is formed with a square eye D which fits on the similar portion D2
of the piston rod on which the piston slides. This rod is of circular formation as
at E, working in gland bearings F as shown and having the pulley G for purposes
of power transmission.
The working of the invention may briefly be described as follows:-Steam or
its equivalent motive power being introduced into cylinder A in the ordinary
manner, the pressure of same impels the piston C in a longitudinal direction and
simultaneously by means of the fixed projection C 2, consequently pressing against
the down side of the spiral B, said piston is made to revolve continuously in the
one direction at such time as the piston arrives at the other end of the cylinder,
it receives steam for the return travel, but the action of the button C2 continues
so resulting in the rotation of the piston as aforesaid.
An exactly similar result is obtained by the alternate mechanism consisting
of the projections and spiral groove being formed on the cylinder and piston
respectively, in this latter construction the piston by its grooves impinges on the
cylinder projections, which action results in the rotation of the piston.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A cylinder being formed with or having in or upon its internal periphery a
continuous or endless recessed groove or path constructed in the nature of a
spiral of any pitch, so that a circuit or partial circuit is obtained by travelling
therein from and to any given point in same, substantially as and for the
purposes herein specified and explained and as illustrated in the accompanying
drawings.
2. A piston beiug formed with or having a projection for engaging and
travelling with above claimed and described spiral path, so causing by such
impinging action its. piston to rotate during the longitudinal travel of latter within
the cylinder, substantially as and for the purposes herein specified and explained
and as illustrated in the accompanying drawings.
3. A cylinder having internal projectious in combination with a
piston formed
upon or in its rim with an endless spiral groove which engages with said pro-
jections, so causing the piston to rotate, substantially as and for the purposes
herein specified and explained.
4. A piston as herein claimed and described, working upon a rod of the
construction as at D 2, so that the piston may travel longitudinally thereon and
at same time rotate and impart such rotation to the rod substantially as and for
the purposes herein specified and explained and as illustrated in the accompanying
drawings.
5. A cylinder constructed as herein claimed and described in combination with
a piston as herein claimed and described, said piston working within the said

page_text: cylinder and mounted on a rod having formations as D2 and E, the whole
associated and working together as a motive power engine, substantially as and
for the purposes herein specified and explained and as illustrated in the
accompanying drawings.
Doted this 13th day of July 1896
F. W. GOLBY,
36, Chancery Lane, London, W.C., Patent Agent for the Applicant.