Automatic Zero-reading Electrical Instruments.
Year: 1894

page_text: Date of Application, 25th May, 1894
Complete Specification Left, 5th Jan., 1895-Accepted, 6th Apr., 1895
PROVISIONAL SPECIFICATION.
Automatic Zero-reading Electrical Instruments.
I, JOSEPH EDMONDSON of Hey Street, Longside Lane, Bradford in the County
of York, Electrical Engineer, do hereby declare the nature of this invention to be
as follows:
This invention consists in the combination with any zero reading electrical
measuring instrument of apparatus for automatically adjusting the zero and for
continuously recording the amount of the adjustment so made, either in the form of
a diagram or (by integration) on a dial or dials.
Taking a Siemens" dynamometer as a sample for a zero reading instrument it is
well known that the angle through which the "torsion head" is rotated to adjust
the zero is proportional upon to the force exerted upon the moving coil by the
current passing through it and the fixed coil respectively.
back to zero.
The first part of this invention therefore consists in the combination of a motor
of any kind with the torsion head such motor being controlled by the moving coil
which, as it leaves the zero causes or permits the motor to rotate the torsion head
in either direction through the angle required to bring the said moving coil
The action of the said motor may be controlled by a stop, catch
or similar devise moved to and fro by the said moving coil as it approaches to
or recedes from the zero. Or the same thing may be accomplished by a contact in
the circuit of the said motor (if it be actuated by electricity) or in the circuit
of an electro-magnet operating a stop, catch, or similar device between the said
motor and the torsion head, the said contact being opened and closed by the said
moving coil as it approaches to or recedes from the zero, or the said moving coil
may cause a friction wheel between two rotating discs to come in contact with one
or other of them (according to the direction of the adjustment required) and may
be geared to communicate their motion to the torsion head. Instead of the friction
wheel and two discs, three bevel wheels and a clutch may be substituted.
To record the adjustments so made, in the form of a continuous diagram, the said
motor may further actuate (either through the torsion head or otherwise) a rack or
other convenient device carrying a pencil or tracer acting against a paper ribbon or
its equivalent, which is caused to travel onwards by clockwork or other convenient
apparatus.
To integrate the adjustments so made and record the result on dials, the said
motor may further actuate (either through. the torsion head or otherwise) a rack or
other device causing a friction wheel to travel longitudinally on a shaft into a
groove of which it has a projection or key. Said shaft being placed radially over
a rotating disc, with the face of which the said friction wheel is in contact, derives
motion from the disc in proportion to the radial distance from the centre of the
disc at which the said friction wheel is placed by the aforesaid motor in adjusting
the zero.
Such motion of the shaft may be communicated to dials by .any con-
venient gearing. A rotating cone (or any similar device) may be substituted for
the rotating disc, is so desired.
It will be seen that all three arrangements above described may be combined in
one instrument, which if the dynamometer be geared up as a Wattmeter, may at
the same time indicate on a dial the watts going into consumption at any moment

page_text: record the variations of the same in a diagram, and register on dials the total
Watt-hours for any required period.
Another mode of integrating current or energy consists in attaching to the
torsion head (either directly or by convenient gearing) a cam coucentrically with
which are mounted a rotating catch and a ratchet wheel forming part of the
registering train. The rotating catch, as it travels over the part of the cam corre-
sponding with the angle of adjustment, engages with the ratchet wheel, which it
carries forward through the said angle and then releases it. An electrical contact
governing the action of a motor driving the registering train may be substituted
for the said cam.
Another mode of integrating current or energy is to give to the torsion head a
uniform reciprocating motion and to register the proportion of the traversed angle
which correspond with the adjustment of the moving coil to zero.
For this
purpose a mangle wheel (or other convenient reciprocating device) is attached to the
torsion head and is geared to a motor working at a uniform speed. The registering
is controlled by the moving coil in various ways of which the following are
examples viz. :-
1st. The moving coil as it approaches to or recedes from, the zero opens or closes
the circuit of an electro magnet the armature of which brings a friction wheel into
contact with a rotating disc or cylinder. Said friction wheel, being geared to the
registering apparatus, communicates to the latter the motion of the said disc or
cylinder, during the period in which the magnet is energised, or vice versa. Toothed
wheels may be substituted for the friction wheel and disc or cylinder.
2nd. The circuit opened and closed by the moving coil may be that of an electro
magnet whose action is controlled by a vibrating contact breaker, and whose
armature actuates a pawl working into a ratchet wheel which forms part of the
registering train.
3rd. The moving coil, instead of opening and closing an electric circuit, may
actuate a stop, catch, or similar device, which shall permit or prevent the action of
mechanism which drives the registering train.
4th. The moving coil may open and close the circuit of an electro magnet the
armature of which actuates a stop, catch or similar device which shall permit or
prevent the action of mechanism which drives the registering train.
Although this invention is herein described as applied to a Siemens' dynamo-
meter it will be evident that it is equally applicable to any zero reading instrument
mutatis mutandis.
The motors herein referred to may be of any kind including ordinary clockwork
and vibrators electrically actuated.
Dated this out. 1
1001
Nic zero-reading Electrical instruments.
JOSEPH EDMONDSON, of Hey Street, Longside Lane, Bradford in the County
of York, Electrical 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 consists in the combination with any zero reading electrical
measuring instrument of apparatus for automatically adjusting the zero and for
continuously recording the amount of the adjustment so made, either in the form of
a diagram, or (by integration) on a dial or dials.

page_text: Taking a Siemen's dynamometer as a sample of a zero reading instrument it is
well known that the angle through which the "torsion head" is rotated to adjust
the zero is proportional to the force exerted upon the moving coil by the current
passing through it, and the fixed coil respectively.
The first part of this invention therefore consists in the combination of a motor
of any kind with the torsion head, such motor being controlled by the moving coil
which, as it leaves the zero causes or permits the motor to rotate the torsion head
in either direction through the angle required to bring the said moving coil back to
zero. The action of the said motor may be controlled by a stop, catch, or similar
device moved to and fro by the said moving coil as it approaches to or recedes from
Or the same thing may be accomplished by a contact in the circuit of
the said motor (if it he actuated by electricity) or in the circuit of an electro-
magnet operating a stop, catch, or similar device between the said motor and the
torsion head, the said contact being opened and closed by the said moving coil as it
approaches to or recedes from the zero.
the zero.
To record the adjustments so made, in the form of a continuous diagram, the said
motor may further actuate (either through the torsion head or otherwise) a rack
or other convenient device carrying a pencil or tracer acting against a paper ribbon
or its equivalent, which is caused to travel onwards by clock work or other convenient
apparatus.
To integrate the adjustments so made and record the result on dials, the said
motor may further actuate (either through the torsion head or otherwise a rack or
other device causing a friction wheel to travel longitudinally on a shaft into a groove
of which it has a projection or key. Said shaft being placed radially over a rotating
disc, with the face of which the said friction wheel is in contact, derives motion
from the disc in proportion to the radial distance from the centre of the disc at
which the said friction wheel is placed by the aforesaid motor in adjusting the zero.
Such motion of the shaft may be communicated to dials by any convenient gearing.
A rotating cone (or any similar device) may be substituted for the rotating disc, if
so desired.
It will be seen that all three arrangments above described may be combined in
one instrument, which if the dynamometer be geared up as a Wattmeter, may at the
same time indicate on a dial the watts going into consumption at any moment,
record the variations of the same in a diagram, and register on dials the total
Watt-hours for any required period.
Another mode of integrating current or energy consists in attaching to the torsion
head (either directly or by convenient gearing) a cam concentrically with which are
mounted a rotating catch and a ratchet wheel forming part of the registering train.
The rotating catch, as it travels over the part of the cam corresponding with the
angle of adjustment, engages with the ratchet wheel, which it carries forward
through the said angle and then releases it. An electrical contact governing the
action of a motor driving the registering train may be substituted for the said cam.
Another mode of integrating current or energy is to give to the torsion head a
uniform reciprocating motion, and to register the proportion of the traversed angle
which correspond with the adjustment of the moving coil to zero. For this purpose
a mangle wheel (or other convenient reciprocating device) is attached to the torsion
head and is geared to a motor working at a uniform speed.
The registering is controlled by the moving coil in various ways of which the
following are examples viz. :-
1st. The moving coil as it approaches to or recedes from the zero, opens or closes
the circuit of an electro magnet, the armature of which brings a friction wheel
into contact with a rotating disc or cylinder. Said friction wheel being geared
to the registering apparatus, communicates to the latter the motion of the said disc
or cylinder during the period in which the magnet is energised, or vice versa.
Toothed wheels may be substituted for the friction wheel and disc or cylinder.
2nd. The circuit opened and closed by the moving coil may be that of an electro
magnet whose action is controlled by a vibrating contact breaker, and whose

page_text: armature actuates a pawl working into a ratchet wheel which forms part of the
registering train.
3rd. The moving coil instead of opening and closing an electric circuit, may
actuate a stop, catch, or similar device, which shall permit or prevent the action of
mechanism which drives the registering train. This is the form I prefer in practice.
4th. The moving coil may open and close the circuit of an electro-magnet, the
armature of which actuates a stop, catch, or similar device, which shall permit or
prevent the action of mechanism which drives the registering train.
Although this invention is herein described as applied to a Siemens' dynamo-
meter, it will be evident that it is equally applicable to any zero reading instrument
mutatis mutandis.
The motors herein referred to may be of any kind including ordinary clockwork
and vibrators electrically actuated.
Such being the nature and object of my said invention, the following is a com-
plete description of same, reference being had to the accompanying drawings in
which similar numbers represent similar parts.
Fig. 1 is a plan view of an automatically adjusted zero reading Watt meter
according to my invention.
Fig. 2 is a front view of parts of the same shewing the motor with its pendulum
and the apparatus for automatically starting the same.
Fig. 3 is a duplicate of a portion of Fig. 2 shewing the levers and stops in a
different position.
Fig. 4 shews the starting apparatus with the armature in a different position from
that in Fig. 2. 1. 1 are the main coils of the dynamometer, 2 is the moveable coil
in the form of two bobbins, wound for high resistance (placed end to end) having
their windings at a right-angle with the windings of their surrounding main coil,
as usual in such instruments, and coupled as a shunt across the terminals of the
main circuit. The bobbins are fixed to a tubular stem as shewn in Fig. 18, and
attached to the centre of the pin-wheel 3 by a torsion suspension spring. The pin-
wheel 3 carries on its axis the index 4, which indicates on the dial 5 the torque of
the dynamometer. The motion of the moving coil is limited by stops (not shewn
in the drawing) to the very small amount required for controlling the action of the
motor as hereinafter described. The tubular stem carries a needle 6 terminating
in two stops 7, 7ª having a gap 8 between them (Figs. 1 and 2).
The motor consists of a pendulum 9, (Figs. 1 and 2) suspended at 9% to an
insulating block 9. Said pendulum carries on its rod an arm 9 carrying a platinum
contact piece 9ª. A gravity impulse arm 10 on its insulated arbor 10 and carrying
platinum contact piece 10b, rests (when the pendulum vibrates to the left) on the
pin 10° fixed in an insulating block 10%.
a
The impulse arm is electrically connected to one of the supply terminals by the
wire 10° the circuit being completed through the contact pieces 10%, 9ª, arm 9,
pendulum and its suspension spring, wire 10 coil of the electro-magnet 11, and
wire 11 to the other supply terminal. The armature 11ª of the electro-magnet 11
carries the insulating block 10%, and is fixed to the arm 11' on the arbor 11, which
also carries the lifting lever 11". The end of this lever is cranked so as to come under
the two horizontal ends 125, 138 of the bell-crank levers 12 and 13. On the arbors
on which the bell-crank levers 12, 13 are fixed, are also fixed the bent levers 12ª, 13*,
which carry the clicks 12, 13 working into the ratchet wheels 14, 15 respectively.
These wheels, mounted on sleeves, run on the arbor 16 with which they are con-
nected by a differential gear situate between them. The arbor 16 carries the
wheel 16 gearing into the wheel 16' on the arbor 16, which by means of the
pinion 16, gives motion to the pin-wheel 3 with its index 4, and the torsion wire
attached to its centre. A (Figs. 2 and 4) is the starting magnet whose circuit is in
series with that of the moving coil on a shunt between the supply terminals. B is
its armature pivoted at C, and attached to an arm D, the upper end of which
(when the circuit is open) rests against the pendulum and holds it in the position
indicated by the dotted lines in Fig. 2. When the circuit is closed, the arm D

page_text: moves to the position shewn in Fig. 4, its intermediate position being shewn by the
full lines in Fig. 2.
The action of the instrument is as follows. The closing of the circuit causes
the magnet A. to attract its armature B and to liberate the pendulum 9, which
immediately commences to vibrate. In its motion to and fro, it makes and breaks
contact between 9 and 10%. The pendulum moving to the right makes contact
at 9 and 10, and travelling still further to the right, carries with it the impulse
arm 10. The said contact closes the circuit of the electro-magnet 11, and causes
it to attract its armature 11ª which carries with it the block 10, and draws down
the pin 10. When the pendulum, returns to the le't, the impulse arm 10 is
arrested from following it by coming in contact with the pin 10%. This breaks
the circuit, the armature 11 recedes from the poles of the magnet and slightly
raises the pin 10%, and the impulse arm 10. Again moving to the right, the
pendulum again makes contact, the magnet lowers the pin 10 which therefore
permits the impulse arm to fall through a space slightly greater than that through
which the pendulum has raised it, and thus to give to the latter the impulse needed
to maintain its vibrations. By this means the magnet 11 and its armature 11*
become a vibrating motor actuating the rest of the mechanism, as well as
maintaining the motion of the pendulum.
The armature 11 in approaching the magnet 11 (when the contact 10°, 9ª is
closed) raises the lifting lever 11ª, the cranked end of which in its turn lifts the
horizontal ends 128, 138 of the bell-crank levers 12, 13. The bent levers 12", 13*
fixed on the arbor of the bell-crank levers 12, 13, carry respectively the two
projecting pins 12°, 13%. In Fig. 2 these are shewn as resting on the two stops 7*
and 7, with the gap 8 between them, the dynamometer and needle 6 being in its
zero position. In this position the motion communicated to the bent levers 12", 13
by the lifting lever 11" is sufficient to liberate the stops (and consequently the
dynamometer) from their damping effect, but not sufficient for clicks 12", 13° to
move their respective ratchet wheels. The moving coil of the dynamometer being
now free, it moves to the right or left according to the direction of the current,
and carries the needle 6 and stops 7ª, 7 with it. In Fig. 3 it is represented as
having moved to the left, and having brought the gap 8 under the pin 13. The
contact 10, 94 being now opened (by the motion of the pendulum to the left) the
lifting arm 11 falls, and with it the bent levers 12, 13 on the arbors of the bell-
crank levers 12 and 13, the former is stopped in its first position by its pin 12
coming onto the stop 7, but the latter having its pin 13 in the gap 8, is free to
fall far enough for its click 13b to take a tooth of the ratchet wheel 15, which it
moves forward when next the lifting arm 11ª raises it. The motion of the wheel 15
is communicated through the differential gear, wheels 16", 16", arbor 16°, and
pinion 16, to the wheel 3 and the index 4, which moves in the direction of the
arrow on the dial 5. Wheel 3 also twists the torsion suspension wire in a direction
opposed to the force exercised by the dynamometer. This operation is repeated
until the force of the torsion wire equals the force of the dynamometer, and brings
the moving coil with its needle 6 and stops 7ª, 7 into the zero position as shewn in
Fig. 2. Both bell-crank levers being now stopped by their pins 12°, 13° coming
into the stops 7, 7, no further motion of the wheel 3 and index 4 takes place until
the equilibrium between the force of the dynamometer and that of the torsion
suspension spring is again disturbed. If such disturbance deflects the moving
coil 2, needle 6, and stops 7%, 7 to the right, and brings the gap 8 under the pin 12,
the bell-crank lever 12 will act by its click on the ratchet wheel 14, whose notion
communicated through the differential gear, wheels 16, 16, arbor 16, and pinion 16ª,
to the wheel 3, will reverse the operation before described till an equilibrium is
again established. Thus it will be seen that the motor adjusts the position of the
needle to the angle corresponding with the torque exerted by the current on the
moving coil of the dynamometer. This constitutes it a self-adjusting zero-reading
instrument.
Fig. 5 is a front view, and Fig. 6 a plan of one form of my invention as applied

page_text: But
to recording the current or energy in the form of a diagram. In this case the
pendulum 9, impulse arm 10, magnet 11, armature 11", though somewhat different
in arrangement, operate as above described in reference to Figs. 1 to 4.
instead of the lifting arm on the arbor 11, I place the lever 11 carrying the
click 11 working into the ratchet wheel 20" on the arbor 20 carrying the worm 20"
geared into the worm wheel 19" on the end of the cylinder 19 carrying the paper
on which the diagram is to be traced. As the armature vibrates it carries with it
the lever 11 which by the click 11', ratchet wheel 20%, arbor 20, worm 20", and
worm wheel 19ª, gives a rotary motion to the cylinder 19. Two electro-
magnets 11, 11, have their circuits in parallel with the circuit of the electro-
magnet 11. Their armatures 12, 13 are attached respectively to the horizontal
ends 12", 13ª of the bell-crank levers 12 and 13, to which are attached the
withdrawing springs 12, 13, and which carry at their other ends the clicks 12, 13,
engaging with ratchet wheels 14, 15, at opposite sides of a differential gear on the
arbor 16, which carries the pinion 16 gearing into the pin wheel 3, the centre of
which carries the moving coil of the dynamometer as described in reference to
Figs. 1 and 2. This pin wheel gears with the toothed wheel 17 on the arbor 17",
carrying a second toothed wheel 17 gearing into the rack 18 on the bar 18, which
is free to move in the direction of its length, and carries the tracer 18°. The
circuits of the electro-magnets 11, 11 are respectively coupled to the contact
pieces 21ª, 21, between which is the contact piece 7 on the needle of the
dynamometer. When the contact piece 7' is deflected to the right by the action
of the dynamometer, it completes the circuit of the electro-magnet 11*, which
becomes intermittently energised simultaneously with the magnet 11, and actuates
the click 12 through the armature 12, bell-crank lever 12", 12, and through the
The pin
.ratchet wheel 14, differential gear, arbor 16, pinion 16", and pin wheel 3.
wheel 3 thus travels in the direction indicated by the arrow in Fig. 6, and when it
has brought the force of the torsion spring into equilibrium with the force of the
dynamometer, it brings the contact piece 7 again into the position shewn in Fig. 5,
At the
and so breaks the circuit of the electro-magnet 11 which ceases to act.
same time the pin wheel 3 acting through the wheel 17, arbor 17", wheel 17",
rack 18" on the sliding bar 18, has brought the tracer 18 into a position corre-
sponding with the torque of the dynamometer. The tracer will consequently trace
on the paper on the moving cylinder a line corresponding with this movement and
this torque.
When the action of the dynamometer deflects the contact piece 7b to
the left, and closes the circuit of the electro-magnet 115, a precisely similar action
ensues, but in an opposite direction, as far as the arbor 16, pinion 164 pin wheel 3,
torsion spring of the dynamometer, wheel 17, arbor 17", rack 18", sliding bar 18,
and tracer 18 are concerned.
It will be seen that this instrument is operated by two vibrating motors, the one
continuously and the other intermittently acting, the action of the latter being
controlled by the contact maker carried by the moving coil of the dynamometer,
both motors having a vibrating contact maker in common. A clockwork movement
might be substituted for the continuously acting motor, whose pendulum or balance
Or each
might act as vibrating contact maker for the intermittently acting motor.
magnet of the intermittently acting motor might have its own vibrating contact
maker (like that of an induction coil for instance) which would commence vibrating
the moment the circuit is closed.
Fig. 7 is a front view, and Fig. 8 a plan of apparatus, according to my invention
for integrating the current which is applicable as a supply meter.
The apparatus for actuating the pin wheel 3 is the same as described in reference
to Figs. 1 and 2, only that the armature 11ª is brought out horizontally from its
arbor 11, and the position of the magnet 11 is altered to correspond therewith.
The said arbor 11 carries the arm 22, to which is attached the withdrawing
spring 22, and which is connected with the arm 22 by the link 22".
The said
arm 22b has a boss 22" free to move round the axis 23ª, to which the ratchet
wheel 23, and disc 24 are fixed.

page_text: The pin wheel 3 gears into the rack 18* on the bar 18 which is free to move
lengthwise and which carries the fork 18 working in a groove 25 on the -boss 25*
of the friction wheel 25, which is free to move lengthwise on the arbor 25%, but.
has a key fitting into the groove 25d by which the rotation of said friction wheel is:
communicated to the said arbor, and through it to the dial train 26. The friction
wheel 25 rests on the flat upper surface of the disc 24, from which it derives its
rotatory motion.
The vibrations of the armature 11* on the arbor 11° are communicated by the
latter to the arm 22, link 22ª, arm 22° with its click 22. The latter gives to the
ratchet wheel 23 and disc 24 a step by step rotatory motion in the direction of
the arrow in Fig. 8. The position of the pin wheel 3 is adjusted to the force of
the dynamometer as described in reference to Figs. 1, 2 and 3, and said pin wheel,
through the rack 18*, bar 18, and fork 18%, adjusts the position of the friction
wbeel 25 longitudinally on its arbor 25° and radially on the disc 24 to correspond..
The disc 24 rotates the friction wheel 2 at a speed proportional to its radial
distance from the centre of the disc, and through the arbor 25°, the amount of the
rotation is integrated and registered by the dial train.
Fig. 9 is a back elevation, Fig. 10 an end view, and Fig. 11 a plan of a second
mode of integrating current or energy according to my invention. Fig. 12 is an
enlarged detail of a joint allowing a rotatory together with an up and down
reciprocating motion as required for one part of the apparatus. Fig. 13 is a front
view of details which could not be shewn in Fig. 9 without confusion. In Fig. 13,.
pendulum 9, impulse arm 10, magnet 11, armature 11", arbor 11, and lifting arm 11",
are the same as described in reference to preceding figures. Bell-crank levers 12
and 13, with their respective horizontal ends 12%, 13, are the same as in Figs. 5.
and 6, but their clicks 12, 13b have tails whose upper surface when in the position
of 13 are arcs of circles struck from the centres of the levers on which they are
placed. These clicks work into ratchet wheels 14, 15 at opposite ends of a
differential gear on the arbor 16, which in this case carries the pinion 16d gearing
into the pin wheel 3, from the centre of which the moving coil of the dynamometer
is suspended by a wire acting as a torsion spring as before described. Two
pawls 12 and 13 prevent the return of the wheels 14, 15, after being moved
forward by the clicks 12, 13. The electro-magnets 29, 30 are coupled in parallel
across the terminals of the instrument, their action being controlled by the contact
piece 7 on the needle of the dynamometer which makes and breaks contact with
the contact screws 21, 21º. The armatures 27, 28 are attached to the levers 27", 28*
hinged on centres at 27, 28, said levers have their ends 27, 28° cranked and
coming over the tails of the clicks 13, 12. The weight of the armatures is.
counterbalanced by withdrawing springs as shewn.
When the dynamometer coil is at zero, or in equilibrium (as before described)
the contact piece 7" on its needle is midway between the contact screws 21, 21",
and the circuits of both the magnets 29, 30 are broken, and the clicks 12, 13b.
engage with the ratchet wheels 14, 15. The lifting lever 11ª being actuated as
before described by the intermittent action of the magnet 11, the bell crank
levers 12, 13, vibrate to and fro, and through their clicks 12, 13b, communicate a.
step by step motion to the ratchet wheels 14, 15 at opposite ends of the differential
gear. The motion of these two wheels being thus equal and opposite, its effect on
the arbor 16 of the differential gear is neutralized, and the pin wheel 3 remains
stationary. But if the contact piece be deflected as shewn in Fig. 13, so as to
close the circuit of the magnet 9, its armature 27 is drawn down, and the click 13.
is taken out of gear.
The click 12 however continues its action, and through the
wheel 14, pinion 16 and pin wheel 3, restores the equilibrium of the dynamometer,
the contact of 7 with 21" being then broken, the armature 27 releases the click 13",
and the action of 12 on the differential arbor is again neutralized. The action
will be reversed if 7b is brought into contact with 21 and thus energizes the
magnet 30.
Turning now to Figs. 9, 10, and 11, it will be seen that the bell-crank lever 12

page_text: has its upper end prolonged to carry a second click 31 taking into the ratchet
wheel 31, on the arbor of which 31, is the pinion 31°, gearing into the upper pin
wheel 32, which is concentric with pin wheel 3, and is free to rotate on the
prolonged arbor 33 of the latter. 34 is a semi-circular disc, fixed to the frame of
the instrument concentrically with arbor 33,-33ª being a similar semi-circular disc
fixed on the arbor 33 with which its centre coincides. These semi disc are so
adjusted, that when no current is passing through, the main coils, their straight
edges coincide, as shewn by the dotted line a Fig. 11. The upper pin wheel 32
forms a base for the registering train 26, which is actuated by the click 26ª on the
lever 26° hinged to the pillar 26° fixed on the upper pin wheel 32. From the
lever 26 a pin 26d projects downwards through the aperture 26°. The lever 26
passes through a slot in the connecting piece 34, such slot being prolonged upwards
so as to allow the connecting piece to descend freely when the lever 26" is prevented
from falling with it as hereafter described.
Fig. 12 is an enlarged view of the top of the connecting piece 34. 34° is a
cylindrical stem with the flange 34 at its lower end. It is attached to the
connecting piece 34 by the screw 34", which leaves the said connecting piece free
to rotate around it. The stem is attached by its forked head 34 and the pin 34",
to the lever 35 moving on its arbor 35ª, and is connected by the link 35b to an eye
on the armature 11ª.
The vibrations of the armature 11 adjust the position of the wheel 3, and the
force of the torsion spring to the force acting on the moving coil of the dynam
meter, as herein before described. In this operation the wheel 3 has moved through
an angle, and has carried with it the semi-disc 33* to an angle which we will assume
to be represented by the dotted line b. (Fig. 11), leaving an angular gap c between
the straight edges of the two semi-discs 33 and 34. The vibrations of the
armature 11 also give a continuous step by step motion to the upper pin wheel 32,
by means of the click 31 (on the bell-crank lever 12), the ratchet wheel 31°,
arbor 31, and pinion 31. The dial train 26, lever 260, and connecting piece 34,
fixed on the upper side of the wheel 32, revolve with it."
The vibrations of the armature 11ª also gives an up and down reciprocating
motion to the lever 26', through the link 35, lever 35, and connecting piece 34.
When in the course of the revolution of the wheel 32, the pin 26ª on the lever 26",
is passing over the gap c (Fig. 11) between the straight edges a and b of the semi-
discs 33, 34, it will rise and fall to the full extent of the motion of the connecting
piece 34, and the click 26ª will record every beat on the dial train. But when the
pin is passing over either of the two discs 33ª, 34, its downward motion is
stopped by one or other of them, and the click 26ª ceases to record the beats on
the dial train. The angle of gap c being proportional to the current or energy,
passing into consumption, the record on the dials is also proportional to the same.
Fig. 14 shews an end view, and Fig. 15 a plan of another form of an integrating
and recording dynamometer or supply meter, according to my invention.
Fig. 16 is a back view of part of the same.
Figs. 17, 17, and 17 shew details of parts of the mechanism and
Fig. 18 a section of the stem of the moving coil or bobbins of the dynamometer,
and the details of its suspension and base.
An eight-threaded screw 36 (Fig. 18) in the frame of the machine, its axis
coinciding with the axis of the dynamometer, and with that of the "mangle wheel"
to be hereafter described, carries a pin 36 entering a tubular opening in the bottom
of the plug 37" at the bottom of the tube 37, to which the bobbins 2 of the dynam
meter are fixed. The function of this screw is to fix and secure the moving coil of
the dynamometer against the bush 38 during transit. The stem 37" of the plug
extends up the tube 37, to above the centre of gravity of the bobbins 2, or moving
coil of the dynamometer, and into its top the suspension spring 37° is firmly fixed.
Said spring (which I prefer to have of cylindrical section) passes upwards through
a hole in the plug 37d at the top of the tube 37, and is fastened firmly into the end
of a plug 37 by which it is firmly fixed in the boss of the arm 39 resting

page_text: "
concentrically on the top of the "mangle wheel 38. 38 is a cylindrical
flanged boss fitting accurately into its, socket bored out of the frame of the
instrument and free to rotate therein. Its flange rests on the frame and
thereby supports the moving coil of the dynamometer through the suspension
spring 37. Its rising in the socket is prevented by a key fitting into the
groove 38. A "mangle wheel" or reciprocating quadrant 38" is fixed con-
centrically on the flange of this boss. To it is fixed the cock 38, which steadies
the plug 37, which is continued downwards into the tubular centre of the boss 38,
wherein it is free to rotate. The spring 38" attached to the cock 38° presses the
arm 39 against the stop screw 38 (Fig. 15) in the bracket 38', fixed to an arm 38°
of the reciprocating quadrant 38*. The function of the stop screw 38 is finely to
adjust the zero of the dynamometer. 40 is a screw in the bracket 40" fixed to the
projection 40 from the frame of the instrument. Said screw is so adjusted that
the arm 39 comes against it just before the pinion 16d begins to turn round the
guide 38 of the zero end of the reciprocating quadrant and prevents the torsion of
the suspension wire 37° beyond its zero position. The arm 39 is free to yield while
the quadrant travels a little further, as it is only held against the stop screw 38°
by the spring 38d. The mangle wheel or reciprocating quadrant is actuated by the
pinion 16 turned in the direction of the arrow (Fig. 17) by its arbor 41, the end of
which nearest to the quadrant is free to move up and down in a slot in the frame,
to allow the pinion to traverse both the upper and the lower sides of the pin teeth
of the quadrant. On the other end of the arbor 41 is a wheel 41° gearing into the
wheel 41° on the arbor 41°, which carries the ratchet wheel 41ª, actuated by the
click 42 carried by the lever 42" on the arbor.11° of the armature 11ª of
the magnet 11 which is the prime mover of all the mechanism of this instrument.
Said arbor 11 carries the lifting arm 11%, which acts upon the horizontal arm of the
bell-crank lever 43 on the arbor 43" which also carries the "pin"lever 44.
crank lever. 43 carries at its upper end, the click 43 working into the ratchet
wheel 45, which drives, the dial train. Bell-crank lever 43 when in its lowest
position rests against the pin 43°, fixed in the frame. The pin-lever 44 is cranked
outwards, so as to come. through an opening 46 (Fig. 16) in the frame. Through
the same opening the forked end 7, 7 of the needle of the dynamometer also
projects, so that 7" acts, when required, as a stop to the lever 44 by coming under
the pin 44. The bell-crank lever 43 can only actuate the dial train when the
pin 44 comes down into the gap 8 of the fork 7, 7. An arbor 47 (Figs. 17, 17^
and 17B) carries near its end immediately under the rim of the mangle wheel 38ª, a
tooth 47 and opposite the lever 43 an arm or lever 47", also opposite the locking
lever 48 another arm or lever 47°. The locking lever 48 rides loosely on the
arbor 45, aud has at one end the tail 48" acted upon by the lever 47, and at the
other end the fork or catch 48° for locking the needle 6 of the dynamometer when
the current is nil. The under side of the guide 38h of the mangle wheel or
reciprocating quadrant when travelling in the direction of the arrow (Fig. 174) acts
as a cam upon the tooth 47, causes the lever 47 partially to revolve and lift the
arms 47 and 47. The former lifts and holds the lever 43, and thereby stops or
prevents the registering. At the same time the latter releases the locking lever 48,
which falls and locks the needle 6 between the projections of the fork or catch 48°.
As the guide 38 returns, it liberates the tooth 47° the levers leave the position
shewn in Fig. 17B, return to that shewn in Fig. 174, and the registering is free to
take place as required. The cam action of the guide 38 on the tooth 47",
arbor 47, arms or levers 47, 47, levers 43 and 48, is timed to take place
simultaneously with the arm 39 coming against the stop screw 38 as before
described, thus insuring a perfectly stable zero and nil position of the
instrument.
".
Bell-
The electrical circuits are as follows:-From the positive terminal 49 of the
main coil the wire 50. connects through the insulated terminal 50°, spiral 50%,
insulated arbor 10, impulse arm 10, contact pieces 10b,' .9d, arm 9°, pendulum
suspension 9 wire 10' to magnet '11, and thence to negative terminal. From the
B

page_text: terminal 50" a wire 51 goes through a resistance coil to one side of a condenser, the
other side of which is connected by wire 51" to top 9" of pendulum suspension,
the object being to protect the contacts 10b, 9d from destruction by sparking, as
described in Specification of Patent No..12468 of the year 1892. Another circuit
passes from terminal 49 by wire 52, terminal 52, wire 52, through moving coil of
dynamometer 2, by wire 52% to terminal 52, and thence by wire 52° through bobbin
of magnet A to negative terminal.
The action of the instrument is as follows:- -The pendulum being started by the
action of the magnet A as described in réference to Fig. 2, the armature 11ª
commences to vibrate and (through the lever 42", click 42, ratchet wheel 41",
wheel 41 gearing into wheel 41, arbor 41 and pinion 160) drives the mangle
wheel 38 which by the well known device of a guide at each end, receives a
reciprocating motion. When the pinion 16" is underneath the pins of the mangle
wheel, such motion twists the upper end of the suspension spring 37°, through an
angle of about 45° in a direction opposed to that of the force exerted (in the
direction of the arrow in Fig. 15) on the moving coil 2 of the dynamometer, by the
current passing through the main coil 1. This mutual force between the two coils
will have moved the coil 2 in the direction of the arrow, until its needle will have
carried its forked end 7, 7" to the right until 7a has come against the stop 7", aud
the pin 44" is free to descend into the gap. 8. This pin 44" receives an up and
down vibratory motion through its lever 44, the arbor 43ª, bell-crank lever 43,-
lifting lever 11 on the arbor 11 of the armature 11". Each time the pin 44ª drops
into and is raised out of the gap 8, it causes the click 43 to take one tooth on the
ratchet wheel 45, and so to register on the dial train. It will continue thus to
count one for every vibration of the armature 11" until the mangle wheel has by
the torsion of the suspension spring, overcome the force of the current, and has
drawn the moving coil of the dynamometer with its needle, and the forked end 7, 7ª
against the stop 7. This brings 7 underneath the pin 44" and stops the
registering. The mangle wheel continues its course, until the pinion having come
to its right hand end (Fig. 15) is guided onto the upper side by the guide 38¹
and reverses the motion of the mangle wheel. The torsion of the suspension
spring 37 being now gradually relaxed,.it comes again to a point at which its force
is overcome by the dynamometer, the moving coil with its needle and fork again
moves against the stop 7", the gap 8 comes under the pin 44%, and the registering
is resumed until the guide 38 approaches the pinion 16ª, depresses the tooth 47%,
and stops the registering by holding up the lever 43, while the pinion is rounding
the zero end of the mangle wheel. This done, the tooth 47" and lever 43 are
released and the registering proceeds as before. This series of actions is repeated
with every reciprocation of the mangle wheel.. The angle of motion of the mangle
wheel, through which the pin 44" is free to drop into the gap 8, being proportional
to the current or energy consumed, the register on the dials is also proportional to
the same.
When the current is nil, the needle and moving coil of the dynamo-
meter are locked by the locking lever 48, whenever the torsion of the suspension
spring is brought to zero by the action of the mangle wheel as before described.
A perfectly stable zero and nil position of the instrument is thus secured.
53, Fig. 16 is a damping spring giving steadiness to the needle. It is lifted
and dropped at every vibration of the armature 11° by an arm 11° attached to the
arbor 11.
A friction spring 54 (Figs. 14 and 15) bears on the flange of the bush 38
(Fig. 18) and gives steadiness to the motion of the mangle wheel. It will be
obvious that a properly constructed cam may take the place of the mangle wheel
and give the required reciprocating motion.
Fig. 19 shews another method of suspending the moving coils 2, which I prefer
to that hereinbefore described. The bracket 56 is fixed to the frame and in it is
secured by the screw 56", the plug 37° into which the suspension wire 37° is firmly
fixed. Inside the bush 38 is a second bush 57 carrying the arm 39. To the lower
end of this bush 57 is attached one end of the spiral spring 58, the other end of

page_text: which is fixed to the collar 59 on the tube 37. The plug 37d at the top of tube 37
is prolonged upwards to within a short distance of the bottom of the plug 37 (see
Fig. 20). The suspension wire, 37° passes through a small hole in the top of the
plug 37. In this arrangement there is no torsion of the suspension wire beyond
the very small amount due to the motion of the coil 2, with its needle 6 between
the stops 7, 7 (Fig. 16). The torque of the mangle wheel 38ª on the moving coil
is exerted through the spiral spring 58 instead of through the suspension wire 37*
as herein before described.
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.) In electrical measuring instruments the combination of the moving part of a
zero-reading dynamometer carrying a stop, with a motor and a device for bringing
the moving part of the dynamometer to zero, the action of the said device being
controlled by the said stop, as herein described and substantially as illustrated by
the accompanying drawings.
(2.) In electrical measuring instruments, the combination of the moving part of a
zero-reading dynamometer carrying a contact maker, with a motor or motors whose
action brings the moving part of the dynamometer to zero when the said motor is
started and stopped by the said contact maker for the purpose of bringing the said
moving part of the dynamometer to zero, as herein described and illustrated by
Figs. 5, 6, and 13 of drawings annexed.
(3.) The combination of either of the arrangements specified in Claims 1 and 2,
with a device for indicating the amount of adjustment required to bring the moving
part of the dynamometer to zero, either by an index and a dial, or by a traced
diagram, or by an integrating and registering train, as herein described and
illustrated by the accompanying drawings.
(4.) In an integrating electrical measuring instrument, the combination of a
vibrating device for integrating, with a stop controlling its action; the position of
the said stop being itself controlled by the moving part of the dynamometer whose
action is to be integrated and recorded as herein described and illustrated by
annexed drawings.
(5.) In electrical measuring instruments the combination of the moving part of a
zero-reading dynamometer with a motor and a mangle wheel or other equivalent
reciprocating device, for purpose herein fully described and illustrated by annexed
drawings Figs. 14 to 19.inclusive.
(6.) The several improved instruments as and for the purpose herein described
and substantially as illustrated by the annexed drawings.
Dated this 4th day of January 1805
BRIERLEY & HOWARD,
Penny Bank Chambers, Halifax, Agents for the Applicant.