Improvements in and relating to Relays.
Year: 1896

page_text: Date of Application, 21st Apr., 1896-Accepted, 30th May, 1896
COMPLETE SPECIFICATION.
Improvements in and relating to Relays.
I, FRANK ERNEST CHAPMAN, of 2 Newbern Avenue, Medford, in the County
of Middlesex, State of Massachusetts, United States of America, Gentleman, 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 has for its object the production of a novel and useful relay, and
consists in the novel features of construction and relative arrangement of parts
hereinafter fully described in the specification, clearly illustrated in the drawings,
and particularly pointed out in the claims.
Reference is to be had to the accompanying one sheet of drawings, forming a
part of this application, in which like characters are used to indicate like parts
wherever they occur.
Figure 1 represents in top plan view a relay constructed in accordance with my
invention.
Figure 2 represents an end view thereof, the arms being shown in section on the
line 2-2 of Figure 1, the electro-maguets being removed.
Figure 3 represente a top plan view of another form in which my invention may
be embodied.
The several elements of my relay may be variously arranged. I employ one
winding of the induction coil to control the armature, and use the other winding to
operate said armature. I employ the word control in the sense of determining in
which direction the armature shall be moved, and by the word operate I refer to
the moving of said armature. The armature may be magnetized by one of the
windings of the induction coil, or it may be magnetized by a separate circuit. In
any case, however, as already stated, one of the windings of the induction coil will
control the armature, while the latter will be operated by the other winding.
Referring to the drawings, in the embodiment of my inventiou therein shown and
selected by me for the purpose of illustrating my invention, a in Figures 1 and 2,
represents an induction coil, composed of a shell a 2, made of soft iron, having a soft
iron head, or end piece at one end. Seoured to the closed end of this shell is a soft
iron core a'. Electro-maguets a 4 are connected to one end of the core a¹ of the
induction coil. As here shown, these electro-magnets a 4 are secured to armis a 3
that project from the shell a 2, and are thus connected to one end of the core a' by
means of said.shell. An armature a 5 is pivoted to tho free end of said core by
means of the screws a 20 passing through the ears a 21, Figure 2, extending from the
top and bottom of said shell. The free end of said armature vibrates between the
open poles a 9, and a 10 of the electro-magnets a 4, making contact with the screws a 7
and a 8, the local circuit h being connected to the armature and one screw a 7 80 as
to be closed when the armature makes contact with said scrow, screw a 8 serving
merely to regulate the play of said armature. a 14 represents a spring connected at
one end to the armature, and at the other end to the adjusting screw a 23 carried by
the arm a 3, Figure 1. This spring serves to keep the armature to one side, opening
the local circuit in the arrangement here shown, when no current is passing
through the instrument, or when not in operation.
b' represents the main, or line circuit, of which 62 is the battery. 6 represents
the primary winding of the induction coil, which may be connected in circuit with
the line The binding posts d3 may be used, if desired, for connecting the
primary winding & with the line wire b' in the usual way.

page_text: represents the secondary winding of the induction coil. This winding is
connected in circuit with the electro-magnets a 4, the coils of said electro-magnets
being wound and connected in such manner that a current passing through them
would make the adjacent ends a 9 and a 10 of opposite polarity. If now, the main
circuit b' be closed, as ordinarily, by means of a key, not shown, located in said
circuit, a current will be caused to flow through the primary winding b. The
direction of the flow of said current will be dependent upon the polarity of the
battery connected to the line, in this caso, assuming it to be of the right polarity
and passing through the primary winding 6 around the core a' in such direction as
to make the armature end of said core north pole, and the end connected to the
shell a 2 a south pole, the magnetism will continue through the closed end of enid
shell, through the shell itself to the open end, through the arms a 3 and cores a 6 of
the electro-magnets, tending to make the adjacent ends a 9 and a 10 of said cores of
like polarity, in this case, two south poles. The armature a 5 connected to the
core a', and practically a continuation of said core, will likewise be magnetized,
the free end of said armature becoming a north pole.
The main current passing through the primary coil b in addition to the
magnetization just mentioned, will induce a momentary current in the secondary
winding, this current passing through the coils of the electro-magnets a 4 in a
certain direction, as hereinbefore described, in this case, tends to make the end a 9
of said electro-magnet a 4 a north pole, momentarily decreasing the magnetism from
the primary coil before described; said secondary current also tends to make the
end a 10 of the electro-magnet a 4 a south pole, this magnetism acting in conjunction
with the magnetism from the primary coil hereinbefore describeil, momentarily
increases the strength of the south pole a 10.
The armature a 5 being north pole, is therefore drawn to the latter side, making
contact with the screw a 7 closing the local circuit. The impulse of the secondary
current now having passed, the ends a 9 and a 10 of the electro-magnets a 4 return to
the primary magnetism equal strength south poles. The armature, however, being
nearer the pole a 10, more force is exerted on it from that side, where it will remain
keeping the local circuit h closed. Now, if the key on the main line be opened, it
stops the current flowing through the primary winding 6, induces a current of
opposite polarity to the first in the secondary winding f. This current passing
around the cores of the electro-magnets a 4 in the opposite direction, reverses in
them the effect of the first current, now increasing the strength of the magnetism
at the south pole a 9, and decreasing it at a 10, the armature not having had time to
wholly demagnetize, will be drawn away from the contact screw a 7 opening the
local circuit h. The spring a 14 having only sufficient tension to hold the armature
when there is no magnetism in the cores a 6, as before described, will now hold the
armature against the stop a 8 leaving the local circuit h open until the main line is
closed again.
.
.
If now, the main line current be reversed, and passing through the primary
winding of the relay, in such direction as to make the armature end of the
core a¹ a south, and the ends a 9 and a 10 of the electro-magnets a 4 north poles, the
current induced by closing the key will be in the opposite direction from the
current induced by closing the key in the case just mentioned, and will, therefore,
have the reverse effect upon the cores of the electro-magnets a 4; now the magnetism
at the pole a 10 will momentarily become strengthened, and the primary magnetism
at a 9 will be weakened, the armature consequently will be drawn toward the
pole a 10 making the contact with the screw a 7, and closing the local circuit h,
the same as in the previous case. Now, by opening the key in the main circuit, the
induced current becomes reversed again, and reverses the effect at a 9 and a 10, as
before described, the armature will be drawn to the stop a 8 and held there by the
spring a 14, or by the residual magnetism remaining in the armature, or core a 6.
As from the nature of the induction coils it is not necessary to absolutely open and
close the primary circuit, but simply increase or decrease the current, to set up.
induced currents in the secondary current, it will be seen that simply increasing

page_text: and decreasing the current on the main line, as on a leaky wire, when a distant
station is transmitting, will operate my relay, and being once adjusted for a
minimum, it will be operated by any heavier current that the wires, with which its
coils are wound are capable of carrying, the heavier currents being only ablo to.
perform the same duty as the smaller, by inducing.a secondary current first in one-
direction when started or increased, and in the opposite direction when stopped or
decreased, throwing the armature from side to side in the same manner as the
smaller current.
In the form shown in Figure 3, the arinature a 5, instead of being pivoted to the
core of the induction coil, is pivoted to the core n of the electro-magnet n' upon
which is arranged an extension of the secondary winding of the induction coil..
The local circuit is connected to the end of the armature, and to the screw a 7, as
in the other figures. The end of the core a' of the induction coil is bent to form.
the pole a 9, while the pole a 10 is formed by an extension of the shell a 2 of the
induction coil, the armature being arranged to vibrate between the poles a 9, a 10 as.
in the other forin.
The operation of this form of relay can be explained as follows:-The primary
winding of the induction coil in circuit with the operating current magnetizes the
core polarizing the adjacent ends to the opposite signs. In addition, it induces
currents in the secondary winding, which induced currents operate the electro-
magnet n momentarily magnetizing the armature a' to the like sigo to one of the
poles of the induction coil and the opposite sign to the other pole, the armaturo
being therefore drawn to the latter side, opening and closing the local circuit, as in
the first named instrument.
This form of construction simply reverses the position of the parts acted upon by
the induced currents. In the first named instruments, the polarity of the armature
remains constant and "operates" while the "controlling" poles of the electro-
magnets are changed from one sign to the other. In the latter case the polarity
of the "operating " poles remains stationary, while the "controlling" armature is
changed from one to the other polarity.
Having now particularly described and ascertained the nature of iny said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. A relay, comprising in its construction, an induction coil, an armature, one
winding of said coil being arranged to operate said armature, the other winding of
said coil being arranged to control said armature.
2. A relay, comprising in its construction, an induction coil, an armature, a part
to control said armature, one winding of said coil being arranged to operate said
armature, the other winding of said coil being arranged to magnetize said part.
3. A relay, comprising in its construction, an induction coil, having windings.
in inductive relation, an armature, means whereby said armaturo is magnetized by
one of the windings of said coil, and means whereby said armature is operated by
another winding of said coil.
4. A relay, comprising in its construction, an induction coil, two electro-magnets
connected to one end of the core of said coil, and in circuit with one winding of
Baid coil, an armature connected to the other end of said core and arranged to be
operated by said electro-magnets, and to be magnetized by the other winding of
Baid coil.
5. An antomatic relay, comprising in its construction, an induction coil, a shell
connected to the core of said coil, two electro-magneta connected to the shell of
said coil, an armature pivoted to the core of said coil, the main circuit connected
to one winding of said coil, the other winding of said coil being continued to
form the winding of said electro-magnets, and a local circuit controlled by said
armature.
6. An automatic relay, comprising in its construction, an induction coil, a shell
connected to the core of said coil, two electro-maguets connected to the shell of

page_text: said coil, an armature pivoted to the core of said coil, the main circuit connected to
the primary winding of said coil, the secondary winding of said coil being continued
to form the winding of said electro-magnets, a local circuit controlled by said
armature, and a spring for holding said armature to one side when there is no
current in the primary winding.
Dated this 27th day of March 1896.
FRANK ERNEST CHAPMAN.
Haseltine, Lake & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.