IMPROVEMENTS IN AND APPLICABLE TO MARINERS COMPASSES
Year: 1884

page_text: PROVISIONAL
I, WILLIAM BATTY of 39 Custom-house Arcade, Liverpool in the County of
Lancaster Nautical Instrument Maker do hereby declare, the nature of my said
invention for IMPROVEMENTS IN AND APPLICABLE TO MARINERS COMPASSES" to
be as follows:-
st
The main objects are so to construct and combine bridges cards and magnets as
to obtain a light compass practically free from oscillation and vibration.
My invention consists first in constructing bridges by which the cards are con-
nected to the central bearing point of suspension, of thin wire or elastic material
bent or curved in such form as to be resilient both horizontally and vertically. In
this manner the card and frame are to a large extent unaffected by vibrating
motion communicated to the supporting needle.
Second. In compass cards suspended as above setforth I hang the directing
magnets by clips a short distance below the compass bridge. The said clips are
formed with or attached to the bridge in any convenient manner and are provided
with screw or other suitable connections by which the magnets may be easily
attached thereto and removed therefrom.
Third. I fit or make compass cards with a depending concentric tubular flange
or ring for the purpose of reducing oscillation or pendulous motion.

page_text: Fig 1 is a perspective' view of a compass card frame with bridges constructed in
accordance with the first part of my invention. The method of attachment of the
directing magnets under the second part is also shown-Figs 2. 3. 4. 5. 6 and 7
are side elevations showing various constructions of spring bridges under my
invention three, four or more bridges may be used." I prefer four as shown in
fig 1.
Fig 1. The frame a of thin wire is connected to the central bearing b by bridges
of thin wire or other suitable resilient material bent into vertical and horizontal
zig zag forms. c d'are the magnets carried by clips é attached to the .frame fin
any convenient manner.. The clips are of any usual or suitable construction.
Fig 2. The bridge springs from diagonal zig zaga.
Fig 3. The zig zag spring is fan shaped.
Fig 4. A scroll spring is used.
Fig 5. A helical spring forms the bridge.
Fig 6. Two helical springs at right angles to each other are.used,
Fig 7. Shows how involute or conical springs may be adapted...
It will be obvious that bridges may be made in many ways under my invention
so as to obtain the desired resilience by the use of springs suitably formed and
arranged, and that the clips for suspending the directing magnets will vary in
construction according to the form of the magnets and the make of the card frame.

page_text: Fig 8 is a side elevation of a compass card part being in section illustrative of
the third part of my invention. g is a tubular flange or ring depending from the
card h on the inner edge thereof for the purpose of preventing oscillation, the said
ring or flange is made of paper or like light material
Compass cards constructed under my invention have the advantage that they
may be suspended on rigid carriers.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
First. Mariners Compasses with spring bridges constructed substantially as
herein setforth.
Second. Bridges for mariners compasses constructed substantially as herein
setforth.
Third. In combination with compasses constructed under the first part of my
invention, clips for carrying the directing magnets, substantially as setforth.
Fourth. Mariners Compasses with depending concentric tubular flange or ring
disposed and arranged substantially in the manner and for the purpose setforth.
Dated this eighth day of July 1885.
J. T. KING,
Per J. Johnson, Agent.