An Improved Construction of Lock, applicable for Miners' Safety Lamps and for other purposes.
Year: 1890

page_text: Date of Application, 7th Aug., 1890
Complete Specification Left, 7th May, 1891-Accepted, 20 h June, 1391
PROVISIONAL DICITICATION.
An Improved Construction of Lock, applicable for Miners' Safety
Lamps and for other purposes.
We, ARTHUR EDMUND WEATHERHEAD of Cranmer Villa, Granville Road,
Wigston Fields, near Leicester, Accountant, and JOSEPH WYATT HANCOCK
of 49 Montagu Road, Clarendon Park, Knighton, Leicester, Gasfitter, do hereby
declare the nature of this invention to be as follows:-
This invention relates to an improved construction of lock applicable for miners'
safety lamps and for other purposes and is designed principally with a view of
preventing miners surreptitiously opening their lamps when in the mine or pit and
thus by exposing the naked light running the risk of explosion of firedamp, and
possible loss of life. The whole of the mechanism may be enclosed in a suitable
casing, having an opening on one or each of its sides and through which may
project a spindle upon which the barrel of the key may be placed.
The key on being placed on the spindle comes into contact with a disc or
equivalent having one or more openings or incisions into which the wards of the
key may be pressed to impart a slight rotary movement to the said disc.
On the same centre or spindle as the disc and at the back thereof is carried a
block or the like having on each of its sides a slotted lever working on a pin fixed
in the casing or elsewhere and which on the block or disc being partly rotated
assume a horizontal position and press outwards the sides of an approximately
semicircular spring whose upper ends are grooved or otherwise adapted to embrace
and secure the end of the vertical rod at the side of the lamp.
A spring controlled pin or equivalent is fixed at the side of the disc to enter a
slot in the latter and is moved away by the insertion of the key.
Dated this 7th day of August 1890
W. P. THOMPSON & BOULT,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Construction of Lock, applicable for Miners' Safety
Lamps and for other purposes.
We, ARTHUR EDMUND WEATHERHEAD of Cranmer Villa, Granville Road,
Wigston Fields, near Leicester, Accountant, and JOSEPH WYATT HANCOCK
of 49 Montague Road, Clarendon Park, Knighton, Leicester, Crasfitter, 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 :-
This invention relates to an improved construction of lock applicable for miners'
safety lamps and for other purposes and is designed principally with a view of
preventing miners surreptitiously opening their lamps when in the mine or pit and
thus, by exposing the naked light, running the risk of explosion of firedamp, and
possible loss of life.
The invention will be understood from the following description in reference to
the accompanying drawings in which,
Figure 1 is a front elevation of a miner's safety lamp, having our improved lock
applied thereto; the front or casing plate of the latter being removed for the sake
of clearness.
Figure 2 is a cross section of the complete lock, and

page_text: Figures 3 and 4 are sectional views on the line X X of Figure 2, shewing the
vertical rod C in its locked and unlocked positions.
Figure 5 is a detail view.
The oil reservoir a is screwed into the upper part of the lamp and the two parts
are further secured or locked together by a rode which passes through the plate d
and ring in the upper end of the lamp, thence downwardly through a groove in
the ringe and into the lock which forms the subject of this invention and by which
the lamp is secured as hereinafter described and for the purpose already mentioned.
The whole of the lock mechanism is enclosed within a casing formed in two
parts and the latter being secured to the oil reservoir a by screws f2 and the
former to by screws as shewn most clearly in Figures and 2.
On the rigid key spindle y, fixed in the rear of the casing, is a boss gl having on
its forward end a disc loosely carried thereon and slightly counterweighted so
that the hole will always return to its lowest position, as shewn in Figure 1.
The said disc is maintained in its position on the boss g by moving between a
larger disc at the back thereof and a collar on the front thereof, both of which
are preferably formed integrally with the said boss.
The disc is provided with a circumferential opening or recess in which is
located a displaceable lug or projection & formed on or with a lever movable on
a pin fixed to the partition plate of the lock casing and maintained in contact
with the peripheral edge of the disc by a spring pressing against the side of the
ensing, all as shewn most clearly in the detail view Figure 5. The disc is also
furnished with a perforation or opening to receive a lug on the upper end of the
spring m in contact with the back face of the disc and fixed by a screw m² to the
partition plate, the latter being formed in two parts and fastened in position by
screws entering internally screw-threaded tubes formed integrally with the
casing.
The boss has also formed thereon a block, movably pivotted between the
forked ends of which, are two slotted plates restricted in their movements by
fixed pins. The outward ends of the slotted plates are in contact with the
sides of a spring o, the central lower portion of which is held between the bottom of
the casing and a projecting piece o¹ formeil thereon, the lateral or sideway movement
of the spring being confined within the limits of the fixed pins p.
The spring is constructed so that iis natural tendency is for the upper ends to
come towards each other, the said ends being recessed or formed as a jaw, to enter
a circular groove in the lower end of the rod c so as to embrace the latter as in
Figures 1, 2 and 4, and thereby prevent the lamp being taken to pieces or the
naked flame exposed to the surrounding atmosphere, until it is again disengaged by
the key in the manner hereinafter described.
The action is as follows:-—
in'
Presuming the key to have been inserted on the spindle it will engage the
opening in the dise and on being turned will move the latter on its axis until
the key comes into contact with the lever and moves it sideways, whereupon the
lug will vacate the opening so that the key on being pressed inwardly will
enter it and also simultaneously enter the perforation in the disc j and displace the
lug
on the upper
end of the spring plate m. The movement of the key being
continued the block will assume an approximately horizontal position and in
doing so will cause the slotted levers to press against the sides of the spring o
and open the jaw or upper end of the latter, thereby allowing the rod c to become
disengaged and admit of the lamp being taken to pieces for filling, trimming,
repairs, or any other necessary purpose, in the usual way.
Unless, when the lever k is moved laterally, the key be pressed inwardly to
engage the disc, as herein before described, the key and the disc h may be turned
at infinitum without actuating the other mechanism of the lock by which the
rod
is disengaged, so that the efforts of anyone unacquainted with the mechanism
of the lock would not be likely to prove successful in endeavouring to open the
lock and disengage the rod c.

page_text: Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The combination in a lock of discs such as ½ and spring controlled lever
such as spring such as m operating substantially in the manner described and
illustrated in the accompanying drawing,
2. The combination in a lock of a block such as n connected to slotted levers
such as spring jaw such as o operating substantially in the manner described and
illustrated in the accompanying drawing.
3. The complete lock consisting of discs such as hand spring controlled lever
such as spring such as m block such as a connected to slotted levers such as n'
spring jaw such as o the whole constructed and operating substantially in the
manner and for the purpose described and illustrated in the accompanying
drawing.
4. The combination with a miner's safety lamp of a lock constructed and
operating substantially in the manner and for the purpose described and illustrated
in the accompanying drawing.
Dated this 6th day of May 1891
ARTHUR EDMUND WEATHERHEAD.
JOSEPH WYATT HANCOCK.
W. P. Thompson & Boult,
Agents for the Applicants.