IMPROVEMENTS IN ENGINE COUNTERS OR APPARATUS FOR REGISTERING THE SPEED OF ENGINES AND OTHER MACHINES
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Robert James Wood at the
Office of the Commissioners of Patents, with his Petition, on the
27th March 1875.
I, ROBERT JAMES WOOD, of the City of Glasgow, in the County of
Lanark, North Britain, Clockmaker, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN ENGINE COUNTERS OR APPARATUS
FOR REGISTERING THE SPEED OF ENGINES AND OTHER MACHINES," to be as
follows:-
This Invention has reference to improvements in the construction
and arrangement of the parts of a counting machine for registering the
number of strokes or revolutions of motive-power engines and other
machines, the distinguishing features and advantages of which are great
simplicity of construction, superior mechanical action, durability, little
liability to derangement, with greater distinctness in the arrangement of
the dial and hands or pointers.
And the nature and novelty of this Invention, which relates more
particularly to the mode of actuating the counter, consist all as
follows The first motion reciprocating rod or spindle is jointed or

page_text: otherwise fixed to an oblong metal plate, which slides within the grooves
or projecting rims of four or other number of pulleys, revolving on fixed
studs arranged on the surface of the back plate of the counter, or a slide
of other convenient form may be adopted. At or near to the centre of
the oblong sliding plate a stud is fixed, which projects and works up
through a slot in the curved end of a lever jointed to or keyed on the
end of an oscillating spindle, which projects and works through both
the front and back plates, and at or close to one edge of the counter.
On the opposite end of this spindle is keyed or otherwise fixed, close to
the front plate, an oscillating pall formed in two parts with the acting
point sliding on and overlapping the main arm of the pall, both fixed
together by screw studs passing through slots in the overlapping feather
of the actuating point of the pall, which permits the outward and
inward oscillation of that end as it is acted upon by a spring, or this
pall may be of other equivalent construction, which would actuate the
star wheel in one direction and pass clear of the teeth in the other
direction.
Instead of using the ratchet wheel on the central part of the back
plate of the counter for moving the main pointer and other wheelwork,
this wheel is arranged and fitted on the front end of the first motion
spindle near the lower part of the front plate of the counter opposite the
said duplex actuating pall. The inner end of the first motion spindle,
on which this ratchet or star wheel is keyed, works in a bearing in the
inner face of the back plate of the counter, and has a pinion upon it
gearing into and transmitting the motion for actuating the pointers to
and through the whole series of wheels carried on their spindles between
the front and back plates held at a proper distance by studs and screws
for that purpose.
On the outer face of the front plate at some distance vertically from
the ratchet or star wheel is fixed a stud, upon which is keyed another
pall, the end of which takes into the teeth of the star wheel at an angle
corresponding to the angle of the teeth on the side of the wheel nearly
opposite to that on which the actuating pall works, and it is held in
position against the face of one tooth and the back of another (nearly
filling the notch) by means of a spring connected to it, and to a lateral;
stud fixed in the plate.
The action of the counter is as follows:-The upward stroke of the
reciprocating rod from the engine by its oblong plate with stud

page_text: reciprocates the slotted lever, which is rigidly fixed on the end of the
reciprocating spindle, on which the moving pall is also rigidly fixed, the
motion of the one communicating an equivalent motion to the other,
the pall turns the ratchet or star wheel tooth by tooth, and with it the
unit pointer on the first motion spindle, and also the other counter
spindles and pointers through their intermediate gearing, and as the
star wheel is turned in the one direction by the actuating pall the
resisting or holding pall retains it at each step from turning in the other
direction.
The defects in engine counters as at present constructed, in which
there is far too little play or freedom of motion of the reciprocating rod
from the engine and moving pall, and great unsteadiness or oscillations
of the unit pointer, as well as abrasion caused by the impact of the
levers upon the back of the wheel teeth, are by means of this Invention
entirely obviated.