Breaking of Circuits Conveying Electric Currents.
Year: 1887

page_text: Date of Application, 31st Oct., 1887
Complete Left, 19th Dec., 1887
Complete Accepted, 20th Jan., 1888
RESERVE
Breaking of Circuits Conveying Electric Currents.
We, CHARLES MARK DORMAN of 24, Brazenose Street, Manchester in the County
of Lancaster, Electrical Engineer and REGINALD ARTHUR SMITH of 24, Brazenose
Street, Manchester in the County of Lancaster, Electrical Engineer do hereby declare
the nature of this invention to be as follows :-
Our invention relates to that class of switch in which rotary motion is transmitted
through the cover of the switch from an external handle to the mechanism inside.
The object of our invention is to obtain a good and approximately airtight fit at
the point where the actuating mechanism passes through the cover in those switches
which are made of material in which perfect accuracy of workmanship is with
difficulty attainable, such as porcelain, vitreous or other incombustible material,
without causing undue friction through the eccentricity of the hole in the cover with
the axis of the internal working parts of the switch.
To carry out our invention we allow the handle of the switch to take its bearing in
the hole in the cover of the switch where it is constrained by means of flanges, or a
gland, or other suitable means; motion being transmitted from the handle to the
working parts of the switch by means of a crankpin and slot, or two crankpins and a
drag-link, or a loosely fitting or flexible connection, or any other suitable method
whereby motion can be transmitted from the handle to the internal mechanism of the
switch when the axes of the two are slightly eccentric, without causing undue
friction.
Dated this 29th day of October 1887.
CHARLES MARK DORMAN.
REGINALD ARTHUR SMITH.

page_text: Breaking of Circuits Conveying Electric Currents.
We, CHARLES MARK DORMAN of 24 Brazenose Street, Manchester in the County
of Lancaster, Electrical Engineer and REGINALD ARTHUR SMITH of 24, Brazenose
Sirect, Manchester in the County of Lancaster, 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 :-
Our invention relates to that class of switch in which rotary motion is transmitted
through the cover of the switch from an external handle to the mechanism inside.
The object of our invention is to obtain a good and approximately airtight fit at the
point where the actuating mechanism passes through the cover in those switches
which are made of material in which perfect accuracy of workmanship is with
difficulty attainable such as porcelain, vitreous or other incombustible material,
without causing undue friction through the eccentricity of the hole in the cover with
the axis of the internal working parts of the switch.
'
To carry out our invention we allow the handle of the switch to take its bearing in
the hole in the cover of the switch, where it is constrained by means of flanges, or a
gland, or other suitable means; motion being transmitted from the handle to the
working parts of the switch by means of a crankpin and slot, or two crankpins and a
drag-link, or a loosely fitting or flexible connection, or any other suitable method
whereby motion can be transmitted from the handle to the internal mechanism of the
switch when the axes of the two are slightly eccentric, without causing undue
friction.
Referring to the drawings which illustrate our improved handle, and two methods
of transmitting the motion from the handle to the mechanism of the switch.
Figs. 1. and 2. are sectional elevations and Fig. 3. a plan of a switch in which the
motion is transmitted by a projection on the mechanism of the switch gearing loosely
with the handle.
Fig. 4. is an elevation and Fig. 5. an underplan of the handle of same.
Fig. 6. is a side elevation and Fig. 7. an underplan of the detachable inner flange
of the handle.
Figs. 8. and 9. are sectional elevations and Fig. 10. a plan of a switch in which the
motion is transmitted by means of a crankpin attached to the handle, gearing in a
slot in the contact arm.
a. is a handle which takes its bearing in a hole in the cover of the switch as shewn.
The handle is retained in its bearing by means of the fixed flange b. at one side, and
the detachable flange c. or the cross-bar d at the other side. The flange c is so shaped
that it embraces the top of the lozenge-shaped came which is attached to the arm of
the switch as shewn in Figs. 1. 2. and 3.

page_text: In Figs. 8. 9. and 10 which shew the crank-pin method of transmitting the motion
fis a crank-pin which is fixed in the cross-bar d and gears loosely in the slot g in the
contact bar h.
The other methods mentioned in this specification of transmitting the motion from
the handle-to the mechanism, are carried out by us by the use of devices already well
know to mechanicians. It will be seen that if the axes of the handle a and the revolving
mechanism of the switch are slightly out of line the handle is still free to turn
round.
We would point out that if the clearance in the gearing is made sufficiently great,
the contact arm can, on leaving the jaw, be caused to dart away under the influence
of a spring to a safe-non-sparking distance as described in the specification of
J. H. Holmes A.D. 1884 14th Feb. No. 3256.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is:
(1.) In a switch of the rotary type, the case of which is made of earthenware or
other incombustible non-conductor of electricity the method of allowing the handle to
take its bearing in the cover of the switch and transmitting the rotary motion from
the handle to the mechanism of the switch by means of a crank-pin and slot, or two
crank-pins and drag-link, or by means of a projection or projections on the handle
gearing loosely with the mechanism of the switch, or a projection or projections on
the mechanism gearing loosely with the handle, or by means of an intermediate piece
or pieces gearing loosely with both handle and mechanism, or by means of a flexible
shaft or coupling, in such a manner that the handle may revolve freely even if the
axes of the handle and mechanism do not perfectly coincide.
Dated this Seventeenth day of December 1887.
CHARLES MARK DORMAN.
REGINALD ARTHUR SMITH.