A New or Improved Method of and Apparatus for Electrically Transmitting Indications or Changes of Position of a Body.
Year: 1895

page_text: Date of Application, 3rd Oct., 1895-Accepted, 9th Nov., 1805
COMPLETE SPECIFICATION.
A New or Improved Method of and Apparatus for Electrically
Transmitting Indications or Changes of Position of a Body.
I, HARRY OTTO Ferdinand BINDEMANN, of No. 6 Ringstrasse, Friedenau,
Berlin, in the Empire of Germany, 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 :—
My invention relates to a new or improved method of and apparatus for electrically
transmitting indications or changes of position of a body whereby certain advantages
are obtained.
In order that my invention may be readily understood I shall hereinafter
describe it with special reference to two typical cases and for that purpose I
shall refer to the accompanying drawings illustrating the said typical cases.
In carrying my invention into effect I employ two or more similar motors of
small size, one nsed in connection with a transmitting apparatus and the other or
others in connection with one or more receiving apparatus. The first of these,
hereinafter termed the transmitting motor is actuated in accordance with the position
or motion of the index or other convenient part of the transmitting mechanism
whilst the second, hereinafter termed the receiving motor actuates a dial by means
of which the indications can be read or be demonstrated. The transmission of the
said position or motion and the indication or demonstration thereof are brought
about by means of the synchronous rotation of the two motors and the action of a
special contact mechanism.
In Fig. show the application of my invention to the transmission, say from
the deck of a ship to another part thereof for steering purposes, of the position of
a compass needle. The compass needle A is pivotted in the usual manner and
carries a light conducting arm a which is in electrical connection with the positive
terminal of the battery G. When the compass is moved by the earth's magnetism
the said arm
a touches one or other of the two contacts b, whereby
one or other of the two circuits is closed either that through the wire c and
switching magnet d or that through wire c' and switching magnet d¹. As
the current flows through oue or other of the switching magnets it attracts
and moves the soft iron armature d². This moves the lever e which by means of a
rode moves also the lever e². The said levers e and 2 are each furnished with two
contact brushes as shown so that according as the armature d' is attracted by the
switching magnets d or d' so one or other set of contact brushes is brought in
contact with the collector f. This form of brush reversing gear is well known in
the art and need not be described more minutely. The connection of the brushes
with the battery G is clearly shown in the drawings and needs no further
explanation. After having traversed the switching magnets the current traverses
the coil of the field magnet f of the receiving motor F and returns to the negative
terminal of the battery. The armature of the receiving motor F now turns in one
direction or in the other according to which part of the collector the contact
brushes touch. By means of a suitable transmitting mechanism the angular
movement of the armature of the receiving motor F is transmitted through the
worm gearing II to the disc J which carries an index or has signs marked upon it
and which may correspond in appearance with the compass dial or with the disc J¹.
It will now be evident that the dial J will be moved angularly in one direction or
the other in accordance with the direction of angular movement of the arm a or
in other words in accordance with the movements of the steering compass.

page_text: The
It is however necessary not only that the disc J should move in the same
direction as the compass needle but that it should move also through exactly the
same angular distance and I attain this desired result as I shall now proceed to
describe. The contacts b, b₁ are screwed to and insulated from the disc J', which
disc is rotated by the transmitting motor F1 through the worm gearing H, this
motor being similar to F in all respects and rotating at the same rate.
current necessary for the switching magnets d³, d of the transmitting apparatus
is obtained by wires shunted across c, c¹ as shown. As both motors are designed to
take equal current and are furnished with similar mechanical mechanism the two
discs and J will rotate synchronou-ly as long as the arm a makes contact
with bor b. Assuming now that the movement of the needle has ceased the
relative position of contacts a or b will be shifted until the circuit is broken the
arm a taking up a position intermediate between 6 and 6. The apparatus is now
ready to receive a new impulse in either direction and through any angular
distance. Assuming that the current be furnished by a small storage battery an.l
that the pressure at both motors is the same (and drop of voltage in the line may
be allowed for by a proportional increase in resistance in the transmitting
motor F) the said motors will, their dimensions and other constants being the
same, rotate synchronously. It is however safer to employ in addition to the
apparatus herein before mentioned, a controlling device whose function is to adjust
any small difference that may arise in the relative positions of discs J and J' due
to unequal angular movements of the motors.
The
Such a controlling device is shown in Fig. 1 and will now be described.
edge of the disc J₁ which is of insulating material has a narrow metallic strip, K
fixed thereon and this strip comes into contact once in every revolution
with the spring contact L' fixed in a certain position and sliding. over the surface
of disc J as the latter moves. The said spring contact L' is electrically connected
with a similar spring contact L of the receiving apparatus, spring contact L taking
the same fixed and relative position with respect to disc J as spring contact L
takes with respect to disc J. The disc J of the receiving apparatus is of
insulating material and has attached to its edge two metallie segments į, j', separated
from one another by a narrow insulating strip M corresponding in width with the
metal strip K of the transmitting apparatus. These segments are connected by
the sliding contact springs through the wires as shown to the switching
magnets d, d².
If now hath dises are turned synchronously the strip K of the
transmitting apparatus will be covered by the spring contact L' whilst the spring
contact L will be over the insulating strip M of the receiving apparatus and no
current will pass won L'Let us assume however that the receiving
motor has either lagged behind or gainel upon the transmitting motor F then
the spring contact 1. will touch one or other of the segments or j', so that current
will pass by J, K, L', electro-magnet N, L through either; or an orto
the switching magnets dor d'. The motor will therefore cause dise J to be
rotated in one direction or the other until the spring contact L covers the strip M
or in other words until the relative positions of the transmitting and the receiving
discs are the same. It would be obvious however that whilst this is going on the
transmitting motor F1 night rotate through a shunt current passing by c, c'. To
avoid this the circuit from the field magnet coils of motor Fare carried to a
meroury cup P into which dips the contact lever Q, through which the circuit is
brought back to the negative terminal of the battery. It will be seen that circuit
is broken whenever current passes between L' and L through the electro-magnet N
lifting out of the mercury cup P, the said circuit remaining open until the disc J
has adjusted its position.
In cases where the problem is simpler, such for example as in the case of a water
level indicar or the like, the app. ratus employed may be a goal deal simplifica
although, under my invention, the general principle remains the same. Such a case
is illustrated in Fig. 2 in which however the motors red rotate in one direction
lyst the sity for brush reversing
day with and Triction

page_text: wheels R R may be employed instead thereof for the purpose of obtaining the
reversal of the direction of rotation of the discs. Such friction wheel reversing
gear is well known and need not therefore be described. Suffice it to say that one
or other of the friction wheels is brought into contact with the disc J' or J by the
switching magnets d d in a manner similar to that described with reference to
Figure 1. The soft iron armature d³ in this case is of the form of a disc rotating
on the same axis as the friction wheels R and R' and rotated by the armature of
the motor F or F¹. It will be seen that as one or other of the switching magnets
attracts the armature d' one or other of the friction wheels R or R' is brought into
contact with the discs J¹ or J and the said discs rotated in one direction or another,
and so as to bring the contacts bb' away from arm a besides turning the disc J
and the indicating dial disc J' through the angle required.
It will be obvious that with slight modifications which will be obvious to
everyone skilled in the art, my invention can be easily used for transmitting the
indications of thermometers, barometers, or indeed of any indicating apparatus in
which the movement of a needle or a dial or other body is to be indicated or
recorded.
It will be seen that I have illustrated my invention in a diagrammatic manner
only; and I have done this for the purpose of facilitating the comprehension of
my invention. Any competent electrical engineer will be able to vary the details
of the apparatus to an indefinite extent without departing from the spirit of my
invention.
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 new or improved method of electrically transmitting indications or changes
of position of a body substantially as set forth.
2. The new or improved apparatus for electrically transmitting indications or
changes of position of a body substantially as set forth.
3. The arrangement and combination of parts substantially as set forth with
reference to Figure 1.
4. The arrangement and combination of parts substantially as set forth with
reference to Figure 2.
Dated this 3rd day of October 1895.