Improvements in or relating to Mechanism for Converting Reciprocating into Rotary Motion.
Year: 1892

page_text: Date of Application, 8th Jan., 1892
Complete Specification Left, 7th Nov., 1892-Accepted, 10th Dec., 1892
PROVISIONAL SPECIFICATION.
Improvements in or relating to Mechanism for Converting
Reciprocating into Rotary Motion.
I, EZRA LOFTS of 32 Station Road, Sundown, Isle of Wight, Engineer, do
hereby declare the nature of this invention to be as follows:-
As this invention can be applied to many widely differing purposes it will be
sufficient to describe the mechanism itself without particular reference to any
special applications, but I may mention as an illustration that it is applicable
to hoisting and winding engines.
By this invention it is intended to devise a mechanism which with a recipro-
cating movement of comparatively small power will afford a rotary movement
of relatively large power, while a backward rotary movement may if desired be
rendered impossible either by the mechanism itself or additional mechanism
provided for the purpose.
In carrying this invention into effect I provide a wheel with angular teeth
which may be more or less like the escapement wheel of a clock and I connect
this with or form it upon any suitable shaft barrel or other part to which the
rotary movement is to be imparted. Or this wheel may itself be the rotary
member. Upon a suitable frame or otherwise so arranged that while their
relative positions do not vary reciprocating motion may be imparted to them I
employ two pallets or equivalent arranged to reciprocate on opposite sides of the
wheel, their arrangement in relation to the wheel being such that as each pallet
enters between two teeth it forces the wheel round a certain distance so that
after the two pallets have operated upon the wheel the latter has been turned
to the extent of one tooth. The amount of movement imparted by each pallet
to the wheel may be evenly divided between them or one pallet may drive the
wheel more than the amount of half a tooth and the other one less.
So long as the required result is obtained the precise arrangement of the pallets
and wheel may be varied but I find that a good result may be obtained by allowing
the back of one tooth to make an angle of 45° degrees with the face of the next
tooth and making one of the pallets with its working face at an angle of 45° degrees
with the back while the plane of reciprocation of the back of the pallet passes
through the centre of the wheel, the exact position and shape of the other pallet
would depend upon the position of the teeth upon the opposite side of the wheel
when the first pallet had effected its movement and this would of course vary with
the shape and arrangement of the teeth and the size of the wheel but the shape and
arrangement of the pallet would preferably be such that when it had completed its
stroke and was fully engaged between the two teeth of the wheel it fairly occupied
that space.
The forward movement would be effected by the angle of the working face of
each pallet not corresponding with the angle of the working face of the tooth upon
which it operated so that as the pallet entered the space between two teeth of the
wheel the wheel would be forced round until the pallet properly occupied the space
between the teeth. The arrangement however as stated at first may vary very
considerably without departing from the spirit of the invention.
Dated this 8th day of January 1892.
W. P. THOMPSON & BOULT,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Mechanism for Converting
Reciprocating into Rotary Motion.
I, EZRA LOFTS, of 32 Station Road, Sandown, Isle of Wight 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:-
As this invention can be applied to many widely differing purposes it will be
sufficient to describe the mechanism itself without particular reference to any special
applications.
In carrying this invention into effect I provide a wheel with angular teeth which
may be more or less like the escapement wheel of a clock and I connect this with
or form it upon any suitable shaft, barrel, or other part to which the rotary move-
ment is to be imparted. Or this wheel may itself be the rotary member. Upon a
suitable frame or otherwise so arranged that while their relative positions do not
vary, reciprocating motion may be imparted to them, I employ two wedges or
equivalent arranged to reciprocate on opposite sides of the wheel, their arrangement
in relation to the wheel being such that as each wedge enters between two teeth it
forces the wheel round a certain distance so that after the two wedges have operated
upon the wheel the latter has been turned to the extent of one tooth. The amount
of movement imparted by each wedge to the wheel may be evenly divided between
them or one wedge may drive the wheel more than the amount of half a tooth and.
the other one less.
The forward movement is effected by the angle of the working face of each
wedge not corresponding with the angle of the working face of the tooth
upon which it operates so that as the wedge enters the space between two teeth the
wheel is forced round until the wedge properly occupies the space between the
teeth. The arrangement however as stated at first may vary very considerably
without departing from the spirit of the invention.
The accompanying drawings serve to illustrate diagrammatically a form of
apparatus by which this invention may be carried into effect, the views are similar
but show different positions of the parts of the apparatus.
Figure 1 sliows it with the bottom wedge engaged with the wheel and the top
wedge entirely clear.
Figure 2 shows the frame carrying the wedges in about its central position, and
Figure 3 shows it in the reverse position to that indicated in Figure 1.
Like letters represent like parts throughout the drawings.
A represents a toothed wheel which may be secured to or form part of the shaft,
spindle, barrel, or other part of the apparatus to which the movement is to be
applied. In this instance this is represented by the shaft B, the movement to be
imparted being of an intermittent rotary character. The operation will be best
understood from Figure 2; the wheel in all the figures rotates in the same direction
as indicated by the arrows. In these figures the wedge frame C is carried in or
supported by any suitable form or arrangement of guides or supports D, and has
imparted to it by any suitable means a reciprocating movement, the 'extremes' of
the two strokes being indicated in Figures 1 and 3. The frame C carries the
wedge-shaped pallets E and F, which are alternately inserted between the teeth of
the wheel A. In Figure 2 the pallet frame C is supposed to be moving in the
direction indicated by the arrow y from top to bottom of the drawing, and the
pallet F has just withdrawn from between the teeth 1 and 2, the back F* of
the pallet F having just cleared the face a of the tooth 2; the pallet E has entered

page_text: between the teeth 3 and 4 and its working face E' is engaged with the back of
the tooth 4. The backs or inclined faces of the teeth of the wheel A are the parts
by which the wheel is moved forward, and the fronts or radial faces a of the teeth
are only used for the purpose of stopping the movement of the wheel. As the
frame C continues to move in the direction of the arrow y in Figure 2 the pallet E
enters farther between the teeth 3 and 4 thus turning the wheel in the direction of
the arrow, and eventually occupies the space between the teeth 3 and 4 as indicated
in Figure 3, by which time the frame C has reached the end of its stroke in that
direction. In the position, Figure 3, the wheel is locked by the tooth E and cannot
be turned in either direction.
Upon the reversal of the movement of the frame C to the direction opposite to
that of the arrow y in Figure 2, the pallet E will be withdrawn from between the
teeth 3 and 4 and the pallet F, after the frame has again reached the position of
Figure 2, will enter between the teeth 2 and 5, the tooth 2 having by the operation
of the pallet E upon tooth 4 been moved round to the position shown in Figure 3,
so that the pallet F enters between the teeth 2 and 5 assuming the corresponding
position to that of the pallet E in Figure 2. Upon the completion of this stroke
the pallet F will occupy the position indicated in Figure 1, between the teeth 2 and 5,
and the wheel will have been turned a space equal to one tooth, tooth 5 in Figure 1
taking the place of tooth 2 in Figure 2. The wheel will now be again locked by
the pallet Fengaging with the teeth 2 and 5. It will therefore be apparent that
the wheel is turned by the wedge-like action of the operating faces E' and F¹ of the
pallets E and F upon the inclined faces of the teeth of the wheel A and that
the wheel is locked alternately by the pallets E and F occupying the spaces
between the adjacent teeth. If therefore the frame C be stopped at the end of
either stroke the wheel will be locked and cannot be moved in either direction.
backward movement may be prevented by any suitable mechanism such as a ratchet
wheel and pawl, a ball-clutch or the like. Should there be no inclination upon the
part of the wheel to turn in the reverse direction as in a simple indicating device,
no special means need be employed to prevent its backward movement though
it is generally desirable to prevent the chance shaking back of the wheel, by
employing at least some means, say friction, in the bearing of the shaft or else-
where, for this purpose.
Its
With this apparatus it will be seen that a positive intermittent rotary movement
is imparted to the wheel which is locked against movement in either direction at
the end of the travel of each pallet. 1 have described the pallets as secured upon
the frame C, and this arrangement is a convenient one, but any convenient means,
either direct or indirect, of connecting the two pallets, may be employed.
This mechanism being arranged to operate in a manner, the reverse of that of
the escapement mechanism of a clock, viz. the pallets driving the wheel instead of
the wheel driving the pallets, the angles of the teeth differ from those of a clock
escapement which are at least usually so made that both faces of the teeth are
inclined to the periphery of the wheel. The teeth of the wheel for my mechanism
I find may be advantageously arranged as indicated in the drawings, viz. with one
face, which is not the working face, lying perpendicular to the periphery of the
wheel, while the other or working face is inclined thereto.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is,-
1. In apparatus for converting reciprocating into rotary motion the combination
with a wheel having teeth whose working faces are respectively perpendicular and
inclined to the periphery of the wheel of pallets or wedges such as E F one of the
working faces of each of which when inserted between the teeth is inclined and
the other perpendicular to the periphery of the wheel substantially as and for the
purpose described and illustrated in the accompanying drawings.

page_text: 2. The combination and arrangement of parts constituting the complete mechanism
for converting reciprocating into rotary motion substantially as described and
illustrated in the accompanying drawings.
Dated this 5th day of November 1809
EZRA LOFTS.
W. P. Thompson & Boult,
Agents for the Applicant.