Year: 1897

page_text: We, EDWARD WILLIAM LLOYD, late Commander R.N., and LEONARD NEWITT,
both of the Elswick Works, Newcastle-upon-Tyne, do hereby declare the nature
of this invention to be as follows:-
The invention relates to an improvement of main switches and is especially
suitable to those used on board ship.
The improved switch consists of a combination of a double knife switch and
a circular switch. The object is to give the means of switching on any one of
several generators to a given circuit. Should there be more than one circuit
a corresponding number of switches are required.
A carrier free to rotate about a central spindle has pivotted to it two knife
switches and a handle. The handle rests on the knives and carries a spring
supporting a yoke passing beneath the knives. These central arrangements can
be turned round the pivot so that each knife shall come opposite to one or other
of two or more pairs of clip electrodes. The inner electrodes are the terminals
of the circuit, the outer electrodes are connected with the generator. When the
central arrangement is turned into position the handle is forced downwards
pressing the knives simultaneously into the jaws of the clip electrodes thus put-
ting each terminal on the circuit into contact with each terminal of the dynamo.
If on the other hand it is required to break the circuit, the handle is lifted up.
The friction of the clip electrodes retains the knives until the spring on the
handle acquires sufficient tension to overcome that friction and as the yoke is
placed close to the pivots about which the knives move, any movement of the yoke is
multiplied at the portion of the knives which make electric contact, the knives
therefore jump out of the clips, thus rapidly and simultaneously breaking the
circuit at four points. Sparking or arcing is by this means reduced to a mini-
mum and on account of the excellent contact made between the knives and clips
when the switch is in connection there is none of the heating which is often
found and always objectionable in ordinary switches.
10
7008

page_text: of this invention and in what manner the same is to be performed to be particu-
larly described and ascertained in and by the following statement:-
-
This invention relates to an improvement of main switches and is especially
suitable to those used on board ship.
The improved switch consists of a combination of a double knife switch and
a circular switch. The object is to give the means of switching on any one of
several generators to a given circuit. Should there be more than one circuit
a corresponding number of switches are required.
Figure 1 is a horizontal section on the line 1-1 Figures 2. and 3. Figure 2
is a side elevation partly in section and Figure 3 is a vertical central section of
an apparatus constructed according to this invention.
A carrier a having a hollow central spindle a¹ free to rotate in a bush 6 has pivotted
to it at c¹ d¹e two knife switches c d and a handle e. The handle rests on the
knives and may carry a spring f supporting a yoke 9 passing beneath the
knives. These central arrangements can be turned round the pivot so that each
knife shall come opposite to one or other of two or more pairs of clip electrodes
preferably of the clip pattern j, k. One set of electrodes j are the terminals of
the circuit, the other set of electrodes k are connected with the generator. When
the central arrangement is turned into position the handle e is forced downwards
pressing the knives c d simultaneously into the jaws of the clip electrodes j k
thus putting each terminal on the circuit into contact with each terminal of the
dynamo. If on the other hand it is required to break the circuit, the handle is
lifted up. The friction of the clip electrodes retains the knives until the spring f
on the handle acquires sufficient tension to overcome that friction and as the
yoke g is placed close to the pivots c¹ d' about which the knives move, any move-
ment of the yoke is multiplied at the portion of the knives which make electric
contact, the knives therefore jump out of the clips, thus rapidly and simulta-
neously breaking the circuit at four points. Sparking or arcing is by this means
reduced to a minimum and on account of the excellent contact made between
the knives and clips when the switch is in connection there is none of the heat-
ing which is often found and always objectionable in ordinary switches.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed we declare that what
we claim is: -
1. A rotating double knife switch.
2. The combination with the subject matter of Claim 1 of the yoke g and
spring f
3 Switches substantially as described and shown in the drawings.
Dated this 23rd day of April 1898.
EDWARD W. LLOYD,
L. NEWITT.