Year: 1885

page_text: I, WILLIAM PEARS JOHNSTON of Calcutta British India, but at present of
Oriental Club Hanover Square in the County of Middlesex, Electrician do hereby
declare the nature of this invention to be as follows:-
:-
My invention relates to a construction of receiving apparatus whereby a current
of electricity is made to produce a movement that can be applied to the making or
breaking of electrical contact, or can be used as in receiving telegraphic apparatus
to work a style or marker, or to actuate a type or counter wheel or other
mechanism. For this purpose, I make a steel magnet in the form of a fork having
two spring limbs or blades; I fix the junction of the blades on a support, and
I attach the point of one of the blades to one pole of an electro magnet, leaving
the other blade free between that pole and the other pole of the electro-magnet.
When no electrical current passes through the coils of the electro-magnet, the free
blade of the steel magnet is attracted to the other blade and remains bearing
against a stop, but when a current is passed through the coils of the electro-
magnet, such as renders each of its poles opposite in polarity to that of the steel
blade which is next to it, then the free blade of the steel magnet, being repelled by
the one pole of the electro-magnet and attracted by the other, is caused to move
away from the other blade. By this movement it may bring together or separate
suitable contact points so as to make or break contact for another current, or it
may work a style or marker or actuate a pawl so as to operate by a ratchet a type
or counter wheel or other mechanism. I provide for effecting adjustment by
moving either pole of the electro-magnet towards or from the other, or by moving
both these poles together, or by turning more or less round in either direction the
support which carries the steel magnet so as to move its free blade towards or from
either pole of the electro-magnet.

page_text: An Improved Electrical Receiving Apparatus for Relay or other
Purposes.
I, WILLIAM PEARS JOHNSTON of Calcutta, British India, but at present of
Oriental Club, Hanover Square, in the County of Middlesex, Electrician, 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 a construction of receiving apparatus whereby a current
of electricity is made to produce a movement that can be applied to the making or
breaking of electrical contact, or can be used, as in receiving telegraphic apparatus,
to work a style or marker, or to netuate a type or counter wheel or other
mechanism. For this purpose, I make a steel magnet in the form of a fork having
two spring limbs or blades; I fix the junction of the blades on a support, and
I attach the point of one of the blades to one pole of an electro-magnet, leaving
the other blade free between that pole and the other pole of the electro magnet.
When no electrical current passes through the coils of the electro magnet, the free
blade of the steel magnet is attracted towards the other blade and remains bearing
against a stop, but when a current is passed through the coils of the electro
magnet, such as renders each of its poles opposite in polarity to that of the steel
blade which is next to it, then the free blade of the steel magnet, being repelled by
the one pole of the electro magnet and attracted by the other, is caused to move
away from the other blade. By this movement it may bring together or separate
suitable contact points so as to make or break contact for another current, or it
may work a style or marker or actuate a pawl so as to operate by a ratchet a type
or counter wheel or other mechanism. I provide for effecting adjustment by
moving either pole of the electro-magnet towards or from the other, or by moving
both these poles together or by turning more or less round in either direction the
support which carries the steel magnet so as to move its free blade towards or from
either pole of the electro-magnet.
Fig. 1 is a side view and Fig. 2 a plan of one form of electrical receiving
instrument according to my invention arranged for making or breaking contact
with the point of an adjustable screw W which may be connected in a local circuit
as shewn. On a non-conducting base are mounted the two coiled cores A and B
of an electro magnet the coils of which are in the circuit of a line wire L to earth
or to a return wire E. By means of a screw C the pole of B can be adjusted
nearer to or farther from the pole of A which can also be adjusted if necessary.
On a vertical axle D is fixed the loop of a permanent steel maguet n m s made in
the form of a fork or elongated U with two spring blades, the one of which m n
has its end fixed to A by a non-magnetic nut e, whilst the other blade m s is free
to move to or from e. From the axle D projects an arm K to which is attached a
spring G, and a setting screw f bears against K. By screwing forward f so as to
press K away in opposition to the spring G, the axle D can be more or less turned
and the spring blade ms can thus be more or less strained towards e.
The one

page_text: wire P of the local circuit being connected to the screw W and the other local
wire H being connected to the axle D and so to the magnet blade m 8, the action
is as follows: While no current passes through the coils of A and B or such a
current as renders A and B respectively of the same polarity as n and s (that is to
say n and & being respectively North and South, when A and B are also North and
South respectively), the blade ms is moved towards e breaking contact with W and
so keeping open the local circuit H to P. But when the coils of A and B are
excited by a current which renders the polarity of A and B respectively opposite
to that of n and 8, then s being attracted towards B makes contact with W, thereby
closing the local circuit H. P.
'
Having now particularly described and ascertained the nature of any said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
The construction and use of an electrical receiving instrument for relay and
other purposes, wherein a permanent steel magnet made with two spring blades in
the form of a fork or elongated U has one of its blades fixed to the one pole of an
electro magnet and has its other blade free to move towards or from the other pole
of the electro magnet, thus closing or opening a local circuit, substantially as herein
described with reference to the accompanying drawings.
ABEL & IMRAY,
Agents for the Applicant.