Improvements in the Construction and Arrangement of Electrical Resistance Coils.
Year: 1899

page_text: Date of Application, 10th Oct., 1899
Complete Specification Left, 6th July, 1900-Accepted, 1st Sept., 1900.
PROVISIONAL SPECIFICATION.
Improvements in the Construction and Arrangement of Electrical
Resistance Coils.
I, WILLIAM GEORGE PYE, of 15, Humberstone Road, Chesterton, in the County
of Cambridge, Scientific Instrument Maker, do hereby declare the nature of this
invention to be as follows:-
My invention relates to an improved form and arrangement of resistance
coils for electrical testing and other purposes, the main features and objects of
which are that all the essential parts are in sight of the operator or user, instead
of covered over as hitherto, and that the resistance in circuit is interchangeable,
and can be quickly and easily altered over a very wide range.
My invention consists of a base of insulating material of any dimensions,
upon which is fixed a series of any desired number of equidistant metallic blocks,
er plates, mounted upon suitable blocks, between each of which and its neigh-
bour a hole, space or recess may be formed or provided in or upon the said
base, and whatever may be the number of such holes, spaces, or recesses, a
ke number of bobbins is provided adapted to engage therewith or be placed
therein.
The said bobbins are each provided from any suitable insulating material, the
lower Hange of which has projecting from its under surface a small cylindrical
stem, while the upper flange is constructed to provide, or has attached thereto,
a suitable projection, adapted to form a handle or finger hold by which the said
bobbin may be rotated. Upon and above, or beneath, the bottom flange or cheek
of the said bobbin are two disconnected metallic pieces or plates, to which are
respectively connected the two ends of the wire with which the bobbin is wound,
the resistance in ohms of the said coil of wire being indicated by numerals or
other signs shewn upon the before mentioned handle or finger hold.
The cylindrical stems at the bottom of the bobbins may be parallel or tapered,
and are adapted to fit loosely into the before mentioned holes recesses or spaces
in or upon the base, each of which said holes recesses or spaces may or may not
be provided with a suitable spring, the tension of which, when used, may operate
ic force the bobbin upwards, so that the said metallic plates upon the said
bobbins may be in electrical contact with the metallic blocks upon the base, and
by which the said bobbins may or may not be retained in position.
The said plates upon the bobbins are so arranged, that when the handles or
finger holds of either bobbin is placed in one position, say at right angles with
the row of blocks upon the base, the said blocks upon each side of the bobbin
are placed in electrical contact with each other by reason of their joint con-
nection with one only of the two plates upon the bobbin, so that a current may
pass without resistance, but by one quarter turn imparted to the said bobbin, so
that the said handle is at right angles with its previous position, the blocks at
either side of the bobbin make contact with one only of the bobbin plates, so
that the current passes from one block to the next through the resistance coil
of the bobbin, and this arrangement obtains with the whole series of blocks and
гл
037

page_text: bobbins, and by reason of the bobbins being easily removed and interchange-
able, and there being no numbers on the base between the said blocks, it is
obvious that coils of any desired resistance may be inserted between any two
blocks at will
In the construction of post office boxes, or Wheatstone bridges upon this prin-
ciple, only two coil gaps would be necessary in the proportional arms, as coils
of any ratio can be inserted therein
T
101
1
1000
GEO. THOS. HYDE,
1, Broad Street Buildings, Liverpool Street, London, E.C.
Agent for the Applicant.
Improvements in the Construction and Arrangement of Electrical
Resistance Coils.
I, WILLIAM GEORGE PYE, of 15, Humberstone Road, Chesterton, in the County
of Cambridge, Scientific Instrument Maker, 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 an improved form and arrangement of resistance
coils in lieu of plugs, for electrical testing and other purposes, the main features
and objects of which are that all the essential parts are in sight of the operator
or user, instead of covered over as hitherto, and that the resistance in circuit is
interchangeable, and can be quickly and easily altered over a very wide range.
In order that the essential particulars of my said invention, and the general
construction and operation of same may be fully understood, reference is herein-
after made to the accompanying sheet of drawings, in which ;
'
Fig. 1 is a plan view and Fig. 2 a side elevation, (partly in section) of a
resistance set according to my invention.
Fig. 3 is an end view of Fig. 2, illustrating the manner in which the insulating
blocks of the terminals and coil connecting plates are set. into a recess in the base.
Fig. 4 is a side elevation, similar to Fig. 2, but illustrating an alternative
arrangement of the resistance coils, Figs. 5 and 6 being details of Fig. 4 herein-
after explained.
Fig. 7 is an under plan view of one of the coils shewn in Fig. 2, while Fig. 8
is a like view of one of the coils used in Fig. 4.
In carrying my invention into effect, I provide of wood, slate, vulcanite, or
any other suitable non-conducting material of any dimensions, a base A, which
for the purposes of the arrangement illustrated by Figs. 1, 2, 3 and 7 has for
preference a connected and detachable bottom plate B, and upon which said
base I have chosen to assume that only one row having six resistance bobbins are
employed, but I wish it understood that such a base may have a like row of
any number of bobbins, or several rows of a lesser or larger number of bobbins,
each of the said rows being placed parallel or otherwise in connection with each
other, the end of one row being electrically connected to the + of the next
row, so that the bobbins may be connected in series.
-
Upon the said base board I provide a series of equidistant metallic plates C,
each mounted upon a block D, of any suitable non-conducting material, set
into a groove E formed in the base A as a precaution against possible lateral
displacement of the said blocks and plates. Between each of the
said blocks D, I provide in the said groove E and the base A

page_text: a preferably circular hole F, (Figs. 1 and 2) in each of which is placed a spiral
or other suitable spring G and plate H, retained therein by any convenient means,
but for preference by that of the bottom plate B.
In each of the said holes F is placed the heel of one of the bobbins, which,
for the purposes of my invention, are constructed of any suitable non-conducting
material, and provided with two flanges J and J', between which the insulated
wire K (of varying guage, and number of turns according to the ohms of resist-
ance required) is wound in the usual way. Upon the upper end of each of the
said bobbins is provided a finger hold L, of any suitable non-conducting material,
preferably set into a groove in the upper flange J, and secured in position by
any suitable means, but which for convenience I prefer to be that of an insulated
or other rod M passing through the stem and both flanges of the bobbin and
screwed or otherwise connected at its upper end with the finger hold L and
screwed or otherwise connected at its lower end with a metallic or other parallel
plug or heel N, which may or may not be formed integral with the flange J,
but for preference the said plug is separate therefrom as shewn, the said plug in
any case being adapted to enter any one of the holes F in the base A.
Upon the bottom of each flange Ji is mounted two metallic separated plates P
and R, held in position by any suitable means, but for preference by that of
screws or the like, enhanced by that of an insulating block S, which serves the
double purpose of insulating the plates P and R from each other and the
plug N, and for pressing against the said plates when the said plug is screwed
or otherwise fixed upon the lower end of the rod M. The plates P and R upon
each bobbin are preferably formed and placed as shewn, more graphically by
Fig. 7, that is to say, they are respectively electrically connected to the primary
and final ends of the bobbin winding, are separated from each other by gaps a
and b and the block S, and collectively form a circular plate of larger diameter
than the flange J¹ and are so formed as to provide recesses c and d.
Upon each of the finger hold L is shewn such numerals or signs as shall
indicate the ohms of resistance of the winding of the bobbin upon which it is
mounted so that the operator may calculate the resistance desired and employ
only such bobbins as shall provide such resistance.
The bobbins are each placed in position by placing the plugs N thereof in
the holes in such a way that the recesses c d of the plates PR are in a position
to clear the conducting plates C, when by pressing the said bobbins in a down-
ward direction, so as to compress the springs G, the plates P and R may be
brought below the conducting plates C, when, if a partial rotation be imparted
to the bobbins the plates P R may be brought beneath the conducting places C
and kept in electrical contact therewith by the tension of the springs G, each of
the plates P being provided with studs e e adapted to collide with one of their
plates C and regulate the distance that the said bobbins may rotate when in
use without their recesses c d being brought beneath the conducting plates, C and
so cause either of the bobbins to leave its seating.
The plates P and R of the first and last of the series of bobbins (when the
bobbins are placed in their respective holes F) make electrical contact with the
first and last of the series of conducting plates C, and also metallic plates C
mounted upon insulated blocks D¹ fixed in the groove E of the base A, the said
plates C carrying terminals T T¹, to which are connected the positive and nega-
tive wires of the circuit.
The plates P and R are for preference so mounted upon their respective
bobbins, that in practice when all the finger holds or handles L are placed in
alignment with the row of bobbins as shewn by,the 1st, 2nd, 3rd, and 4th bobbins
in Figs. 1 and 2, all the plates P of the bobbins would be in electrical contact
with their respective forward conducting plates C while the plates R would all
be in electrical contact with their backward conducting plates C, so that a
current could only pass from the terminal T to terminal T₁ by passing through
the coils of the interposed bobbins, thus interposing within the circuit a resist-

page_text: ance equal to the combined resistance of all the bobbin windings, but if all the
handles L be placed at right angles to that of the row of bobbins, as indicated by
the 5th coil in Figs. 1 and 2, the plates P of all the bobbins would be in contact
with each pair of the conducting plates C, so that the current would pass from T
to T through all the connected plates P and C all the plates R and the coils K
being thrown out of circuit as shewn in Figs. 1 and 2.
It will thus be understood that only such of the bobbins the handles of which
are placed in alignment with the series of bobbins would interpose any resist-
ance in the circuit, and that any or all of the said bobbins or coils of whatever
resistance value, may be placed in and out of use instantly, or that any one
bobbin or coil may be instantly removed (as shewn by the vacant position for
the 6th bobbin or coil in Figs. 1 and 2) and replaced by another of greater or
lesser resistance as required, and this obtains with the whole series of bobbins
irrespective of their number or resistance value, there being no numbers used
upon the base to confound the operator.
As an alternative arrangement, and may be for commercial reasons, I may
dispense with the springs G and the plates P and R upon the bobbins or coils
and in lieu of the latter I may elongate the stem of the bobbin to extend at h
below the flange J¹, and screw or otherwise fix upon the under face of the said
flange, a pair of plates f and f¹, provided respectively with semi-circular
nosings and g¹ (Fig. 5) the latter then almost surrounding the elongation h
and separated from each other only by gaps m ml, the said plates f and f¹ being
electrically connected with the two ends of the bobbin winding.
In this arrangement metallic plates C may be fixed upon the base A within
the groove E, or upon insulated blocks therein, and flush with or projecting
above the level of A, the ends of the said plates C being arranged to coincide
with the holes F between and within which the nosings g g of the bobbins or
coils would be inserted, the resistance of the bobbins being interposed when
the handles L are placed in such a position that, say the plate for nosing g or
both are in electrical contact with one conducting plate C, while the plate fl
or nosing or both are in contact with the other, as shewn by the left hand
bobbin of Fig. 4, the resistance of the bobbins being thrown out when the
handles L and their bobbins have received one quarter turn, and both the
plates for the nosings g g or both are in contact with both the conducting
plates C as shewn by the right hand bobbin of Fig. 4.
In this arrangement also, by reason of the resistance coils or bobbins being
easily removed and interchangeable, any desired resistance, according to the
individual or combined resistance value of the bobbins may be quickly and easily
placed in or out of circuit at the will of the operator.
In the construction of post office boxes, and Wheatstone bridges, according
to my invention, only two coil gaps or holes F would be necessary in the pro-
portional arms, as coils of any ratio or resistance value may be inserted therein.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
-
(1) The herein described system of, and means for, employing detachable
resistance coils or bobbins of varying resistance value in post office boxes, Wheat-
stone bridges and like electrical testing apparatus, substantially as set forth
and shewn.
(2) The construction and use of portable resistance coils or bobbins in the
manufacture of electrical testing apparatus substantially as described and shewn.
(3) The improved electrical testing apparatus, consisting of a base A, pro-
vided with a groove or grooves E, wherein is formed a series of holes F, each
provided with a spring such as G, and receiving a plug projection such as N,
upon the lower end of a wire wound resistance bobbin or coil K having flanges J J
the latter carrying plates P and R in electrical connection with the bobbin

page_text: winding K, and so arranged that both may be placed in electrical contact with
their respective conducting plates C, mounted upon insulated blocks D fixed at
each side of the holes F upon the base A, for placing the winding of the said
bobbins in circuit, or that the plate P only may be placed in contact with the
said plates C for throwing the bobbin winding K out of circuit, when partial
rotation is imparted to the said bobbin by means of a finger hold or handle L,
the whole connected, combined and operating substantially as and for the pur-
poses herein described and shewn by the appended drawings.
(4) The improved electrical testing apparatus, consisting of a base A, with
or without a groove or grooves E, and provided with a series of holes F for
receiving the nosings g g of plates f f¹ mounted upon the lower flange J¹ of a
wire wound resistance bobbin K, having a finger hold L, the said plates f fl
being in electrical connection with the winding of the said bobbin, and adapted to
collectively or individually make contact with a pair of conducting plates C
upon the base A for throwing the said resistance bobbins in. and out of circuit
said bobbin, substantially as set forth and shewn.
(5) The improved bobbin for electrical resistance purposes, consisting of a
reel having flanges J J¹ and finger hold L, the latter held in position by a
central rod M passing through the stem of the said reel, and engaging with a
plug N embracing an insulating block S in touch with a pair of metallic
plates PR, fixed upon the flange J and in electrical connection with the wind-
ing K of the said bobbins, substantially as set forth and shewn.
(6) The improved bobbin for electrical resistance purposes consisting of a
reel having a finger hold L and flanges J J¹, the latter carrying a pair of
plates with nosings g g in electrical connection with the winding K of the
said bobbin, substantially as set forth and shewn.
Dated this fith day of July 1900
GEO. THOS. HYDE,
1, Broad Street Buildings, Liverpool Street, London, E.C.
Agent for the Applicant.