Improvements in or relating to Electric Meters, Recording Apparatus, and Controlling Gear.
Year: 1892

page_text: Date of Application, 21st July, 1892
Complete Specification Left, 21st Apr., 1893-Accepted, 21st July, 1893
PROVISIONAL SPECIFICATION.
Improvements in or relating to Electric Meters, Recording Apparatus,
and Controlling Gear.
I, WILFRID L. SPENCE The Elms, Seymour Grove, Manchester, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to that class of electricity meter, or electric controlling
gear, in which an approximately constant speed motor drives through a variable
speed gear a registering index, series of indices, or other device, which variable speed
gear is controlled by the solenoid action of an electric current.
It consists in the application to electric measuring, recording and controlling
purposes of the well known star-wheel and tappet or wiper gear which is usually put
on paper-making machines for the purpose of keeping the web straight.
For example in my improved electricity (amper-hour) meter I provide a constant
speed motor, (which may be of any suitable form, e.g., clockwork or electro-magnetic),
this drives continuously a spindle to which is rigidly attached the wiper whose
working edge (the limit of the radius) is curved or "stepped," and whose length is
determined so as to correspond with the motion of the star-wheel hereafter
described. This star-wheel having, say, 8, 12, or 16 points, is mounted on a
spindle which it drives through a feather key or equivalent device so as to be
capable of longitudinal motion from end to end. This spindle actuates the
recording or controlling gear and rotates faster or slower according to the position
of the star wheel thereon, which position in its turn is determined by the motion of
an armature or core working in conjunction with a solenoid through which the
current to be measured or regulated is passed. Thus suppose no current is flowing:
The armature is released and the star wheel moves, under gravity or other opposing
force, to a position on its spindle where the revolving tappet does not touch it
hence the recording or other gear remains at rest. If, now, lamps equal to, say,
one-half the capacity of the meter be turned on, the solenoid attracting its armature
draws the star-wheel along its spindle so as to be opposite the point of mean
equivalent radius on the tappet, the latter at every revolution now strikes the
wheel and turns it through a distance corresponding to the radius of the tappet
at the point of contact hence the recording gear advances by an appropriate
amount.
The application to electrically controlled regulating devices is equally simple.
The solenoid, armature or core, connecting link and star wheel remain as in the
foregoing example, but now for the one shaft and wiper two parallel ones rotating
in opposite directions are substituted and between them the star wheel spindle is
mounted. The two wipers, it will be understood, also have the taper (from large to
small radius) in opposite directions. Hence according to the electrically controlled
position of the star wheel, whether towards one end, in the middle, or at the other
end of its travel a right-handed, zero, or left handed rotation respectively will be
imparted to its spindle and this may operate any desired device, such, for instance,
as a steam valve, a resistance switch, or a feed motion for an arc lamp. This
same arrangement is excellently well adapted for application in a secondary battery
meter in which the current of discharge must be subtracted from the charging
current.
T1 1900
WILFRID L. SPENCE.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Electric Meters, Recording Apparatus,
and Controlling Gear.
I WILFRID L. SPENCE of 9, Newark Drive, Pollokshields, N.B., Civil
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 :-
My invention relates to that class of electricity meter or electric controlling
gear in which an approximately constant speed motor drives through a variable
speed gear a registering index, series of indices, or other device, which variable speed
gear is controlled by the solenoid action of an electric current.
It consists in the application to electric measuring, recording and controlling
purposes of the well known star wheel and tappet or wiper gear which is usually
put on paper making machines for the purpose of keeping the web straight.
For example in my improved electricity (ampere-hour) meter I provide a
constant speed motor-which may be of any suitable form, e.g., clockwork or
electro-magnetic-this drives continuously a spindle to which is rigidly attached
the wiper whose working edge-the limit of the radius-is curved or stepped and
whose length is determined so as to correspond with the motion of the star-wheel
hereafter described. This star wheel having, say, 8, 12, 16 or any workable
number of points is mounted on a spindle which it drives through a feather key or
equivalent device so as to be capable of longitudinal motion from end to end. This
spindle actuates the recording or controlling gear and rotates faster or slower
according to the position of the star wheel thereon, which position in its turn is
determined by the motion of an armature or core working in conjunction with a
solenoid through which the current to be measured or regulated is passed.
rest.
Thus suppose no current is flowing the armature is released and the star wheel
moves, under gravity or other opposing force, to a position on its spindle where the
revolving tappet does not touch it hence the recording or other gear remains at
If now lamps equal to, say, one half the capacity of the meter be turned on
the, solenoid attracting its armature draws the star wheel along its spindle so as to
be opposite the point of mean equivalent radius on the tappet, the latter at every
revolution now strikes the wheel and turns it through a distance corresponding to
the radius of the tappet at the point of contact, hence the recording gear advances
by an appropriate amount.
The application to electrically controlled regulating devices is equally simple.
The solenoid, armature or core, connecting link and star wheel remain as in the
previous example but now for the one shaft and wiper two parallel ones rotating in
opposite directions are substituted, and between them the star wheel spindle is
mounted.
The two wipers, it will be understood, also have the taper (from large
to small radius) in opposite directions. Hence according to the electrically
controlled position of the star wheel, towards one end, in the middle, or at the
other end of its travel a right-handed, zero, or left handed rotation respectively
will be imparted to its spindle and this may operate any desired device, such
for instance, as a steam valve, a resistance switch, or a feed motion for an arc
lamp. This same arrangement is excellently well adapted for application in a
secondary battery meter in which the current of discharge must be subtracted
from the charging current.
I will now describe my invention with reference to the drawings.
Figure 1 shows the general principle, (the application to paper making machines
is shown in the drawings accompanying Specification 16961, 1884 and elsewhere),
a star or pin wheel, P, is mounted on a spindle which it drives through a feather
key s as to be capable of longitudinal movement thereon. A tappet or wiper, W,

page_text: is carried by a rotating shaft so as to gear with the pin wheel, P; the depth of
gear and the number of teeth through which the star wheel is rotated is regulated
by the position of P on its spindle and this is controlled by any suitable arrange-
ment of solenoid S, and core C, a spring or other opposing force acts on the star
wheel as well as the solenoid and it is by these opposite forces balancing in
different positions according to the strength of the current that the wheel moves
to a place where it is turned through an angle corresponding to the current to be
measured.
Figures 2 and 3 show an arrangement by which the capacity and delicacy for a
given size are increased. The centres of the wheel and tappet are brought close
together so that one or other gears internally. P is the pin wheel and R and R' the
limits of the radius of the wiper.
The proper curve to give the wiper so as to rotate the wheel through proportionate
angles is readily found as shown in Figure 2. The travel, O A, of the tappet on
its spindle is divided into any number of equal parts, say 100. Then for each
movement equal to one of these divisions the wiper must rotate. the pin-wheel
through one-hundredth of the number of pins that it can affect at full stroke.
Thus suppose with the maximum current flowing through the solenoid the wiper
moves to a position where it rotates the pin wheel through 100 points, then
with 75% of this current the number of points carried round at each revolution of
the wiper must be 75.
By setting off the travel of the wiper as ordinates along O A, and the number of
pins along OB (OB being equal to R-R¹) a series of points can at once be
plotted down showing the radius required to carry round any given number of
pins. The curve drawn through these points is the limit of the radii of the wiper.
If in addition the curve relating current strength in the controlling solenoid with
the motion of its core is known the two may be combined so as to give strictly
proportionate readings for all current strengths.
It is convenient in some cases to make the wiper of a piece of wire bent to the
proper shape and over hanging the pin wheel as shown in Figure 3. This form
works most freely.
If desired the wiper instead of the wheel or wheels may be moved by the
solenoid, so long as relative motion is secured it matters not which is the fixed
portion.
I would have it understood that I do not claim any particular form of solenoid
and core nor do I limit myself thereto, but
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. The application to electric measuring, recording and controlling purposes of a
star or pin wheel and tappet gear substantially as described.
2. In an electric measuring, recording or controlling apparatus the star or pin
wheel and wiper gearing internally and externally substantially as described.
3. In an electric measuring, recording or controlling apparatus constructing the
working edge of the wiper substantially as and for the purposes described.
Dated this 20th day of April 1893.
WILFRID L. SPENCE.