An Improved Safety Lamp for Miners and for Domestic and other Purposes.
Year: 1890

page_text: Date of Application, 12th Nov., 1890
Complete Specification Left, 11th Aug., 1891-Accepted, 12th Sept., 1891
PROVISIONAL SPECIFICATION.
An Improved Safety Lamp for Miners and for Domestic and other
Purposes.
We JOSEPH PRESTWICH of 8 Irwell Park Eccles in the County of Lancaster
Agent and THE PROTECTOR LAMP AND LIGHTING COMPANY LIMITED also of
Eccles in the said County, Lamp Manufacturers do hereby declare the nature
of this invention to be as follows:-
Our invention applies to that description of safety lamps wherein the flame is
enclosed in a strong glass or wire gauze cylinder, and access thereto can only be
obtained by unscrewing the oil reservoir or lamp bottom; whilst a device is attached
thereto whereby when the bottom is unscrewed this action draws the wick into a
tube or shell which extinguishes the flame.
The object of the invention is to render the manufacture more simple and
economical and to dispense with the necessity for the special locking device usually
employed for such lamps. The central screw is also dispensed with and the lamp
is much firmer and less liable to become broken. The improved lamp also can be
used with a round or flat wick.
We make the oil receiver with the top open or cut away all but a rim of sufficient
strength to carry an internal and an external screw and of smaller diameter than
the outside of the reservoir.
The internal screw carries the burner plate which fits therein and forms the top
of the vessel, or if preferred the burner plate may be soldered on, or made all in
one piece with the body. It is provided at the centre with a flat or round wick
tube on each side of which (or on one side only) is a projecting stud for a purpose
hereinafter named.
We also provide a ring of about the same external diameter as the reservoir and
having a screw thread cut on its inside of such a diameter and pitch as will
enable it to be screwed onto the external screw of the rim at the top of the reservoir
above mentioned.
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The ring is deeper than the rim and into its upper part above the rim we
screw the following-up plate" which holds the glass or gauze cylinder. This
"following-up-plate is provided with a tube or shell in the centre fitting close
round the wick holder or tube, and with a hole or holes fitting onto the
projecting stud or studs on the burner plate. Or if preferred the holes may
be made in the burner plate and the studs attached to the following plate. If the
wick holder and shell are flat instead of tubular the latter must be provided with
a flange at the bottom turning in a hole in the following-up plate, but if they
are both tubular one can turn in or upon the other.
The holes in the "following-up plate" are made preferably with inclined leading
lots and when the lamp is lighted and screwed together the pins on the burner
olate enter the holes in the "following-up-plate," and the wick holder and shell are
crewed up at the same time. But on unscrewing the bottom the pins are withdrawn
rom the holes leaving the following plate at the top of the ring and the wick tube
r holder being thus drawn down into the shell the light is extinguished before
he bottom can be removed.
Dated this 11th day of November 1890.
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
An Improved Safety Lamp for Miners and for Domestic and other
Purposes.
We JOSEPH PRESTWICH of 8 Irwell Park Eccles in the County of Lancaster
Agent and THE PROTECTOR LAMP AND LIGHTING COMPANY LIMITED also of
Eccles in the said County Lamp Manufacturers 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 applies to that description of safety lamp wherein the flame is
enclosed in a strong glass or wire gauze cylinder, and access thereto can only
be obtained by unscrewing the oil reservoir or lamp bottom; whilst a device is
attached thereto, whereby when the bottom is unscrewed, this action draws the
wick into a tube or shell which extinguishes the flame.
The objects of the invention are to render the manufacture of such safety lamps
more simple and economical and to dispense with the necessity for the special
locking device usually employed for such lamps.
The central screw is also dispensed with and the lamp is much firmer and less
liable to become broken.
The improved lamp also can be made for a round or a flat wick.
The nature of the said invention and the manner in which the same is to be
performed or carried into practical effect will be readily understood on reference to
the accompanying sheet of drawings and the following explanation thereof.
Fig. 1. on the drawing is a vertical section of the lower part of a safety lamp
of the class above referred to as adapted to burn mineral or hydro-carbon oil with
a flat wick and made according to the present invention, and Fig. 2 is a horizontal
section of the same.
Fig. 3 is an elevation (partly in section) of a slight modification of the same
adapted to burn spirit and provided with a round wick tube.
Figs. 4 and 5 are views of detached parts hereinafter more particularly
referred to.
Referring to Figs. 1 and 2 I make the oil receiver a with the top open or cut
away all but a rim b of sufficient strength to carry an internal screw 61 and an
external screw 62 the latter of which is of smaller diameter than the outside of the
reservoir a.
The internal screw b¹ carries the burner plate c which is chased with an external
screw fitting therein and forms the top of the oil vessel a or if preferred this
plate c is made in the form of a thin disc (as shown in the detached section Fig. 4.)
and is held in position by means of a screwed ring d. Or the burner plate c may
be soldered to an internal rim cast on the interior of the oil reservoir as shown at
Fig. 3.
In either case it is provided, at the centre with a wick tube e which may be
either flat as shown at Figs. 1. 2. 4 and 5. or round as shown at Fig. 3. and (as
shown at Fig. 1.) the top of the plate e is provided with either one or two pins f
for a purpose hereinafter described.
A ring g (Fig. 1.) is also provided of about the same external diameter as the
oil reservoir a and having a screw thread cut on its inside of such a diameter and
pitch as will enable it to be secured onto the external screw 62, of the rim b at the
top of the reservoir a.
This ring g is deeper than the rim b and into its upper part above the rim bis
screwed the following-up plate h which holds the glass h* (or gauze cylinder) in
position.
This following-up plate (see Figs. 1 and 5) is provided with a tube or shell i
in the centre fitting close round the wick holder or tube e, and with a hole or
holes below (see Fig. 5) fitting onto the projecting stud or studs on the upper
side of the burner plate. Or if preferred the holes may be made in the burner
plate and the pins or studs attached to the following-up plate.

page_text: 5
If the wick holder e and shell are flat (as shown at Figs. 1. 2. 4. and 5)
the latter must be provided with a flange i at the bottom (Figs. 1 and 5) turning
in a hole in the following-up plate but if they are both tubular as shown at
Fig. 3, one can turn in or upon the other.
The holes in the following-up plate h (see Fig. 5) are made preferably with
inclined leading slots, and when the lamp is lighted and screwed together the pins
or studs on the burner plate enter the holes in the following-up plate and thus
the wick holder or tube e and its shell are both screwed up at the same time.
But on unscrewing the bottom or oil reservoir a the studs or pins fare gradually
withdrawn from the holes & leaving the following-up plate in the top of the ring g
and as the unscrewing proceeds the wick tube or holder e is thus drawn down into
the shell and the light is extinguished before the bottom or oil reservoir a can
be removed.
Instead of attaching pins to the burner plate c as above described one stud fx
may be attached to the top of the rim as shown at Fig. 2 and a corresponding
pin (shown by the small dotted circle) fixed to the lower side of the following-up
plate. As soon as the unscrewing commences one of these studs moves away from
the other and the following-up plate is left behind.
It will be understood that when the oil reservoir has been removed and before
the lamp is lighted this plate must be withdrawn by unscrewing with a key
provided for that purpose so that the shell i may be placed over the wick tube e
before the wick is lighted after which they are both screwed up together as before
stated. .
If this withdrawing of the plate which supports the glass cylinder * or
wire gauze should be objected to I sometimes place between the glass * and the
following-up plate h a screwed ring as shown at Fig. 3. which will keep the glass
in its place when the plate his removed for lighting purposes.
A simple locking device for this lamp is made by dropping a steel pin m (see
Fig. 1.) through a hole in the ring g into a corresponding hole in the oil reservoir
(as shown on Fig. 1.) or in front of a pin thereon (as shown at Fig. 3).
The top of this pin m is fixed in a plate n resting on a lug
fixed to the ring g. The plate and the lug are provided with corresponding holes
and are secured together in the well known manner by a leaden rivet p.
o cast on or
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 :-
First. The general construction and combination of parts constituting an
improved safety lamp for miners, and for domestic and other purposes substantially
as hereinbefore described and illustrated by the drawings annexed.
Secondly. I claim the combination in such lamps of the burner plate c and the
shell plate or following-up plate with the oil reservoir a (substantially in the
manner described and illustrated) in such a way that when the lamp is lighted and
the oil reservoir is screwed on the burner plate and shell plate are screwed-up
simultaneously; and on the contrary when the oil reservoir is unscrewed it with-
draws the burner plate only, leaving the shell plate or following-up plate in the
lamp, whereby the wick is drawn down through the shell and the flame thereby
extinguished.
Thirdly. As applied to lamps with flat wick tubes I claim the combination with
he following up plate of a flat shell fitted with a small plate capable of revolving
n a circular hole in the following up plate.
Dated this 10th day of July 1891.
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicants.