Improvements in Miners' and other Safety Lamps.
Year: 1893

page_text: Date of Application, 21st Feb., 1893
Complete Specification Left, 4th Oct., 1893-Accepted, 4th Nov., 1893
PROVISIONAL SPECIFICATION.
Improvements in Miners' and other Safety Lamps.
I JOSEPH PRESTWICH of Irwell Park Eccles, near Manchester, in the 'County
of Lancaster, Manager, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the construction of that kind of miners' and other
safety lamps which can be lighted by electricity without opening the lamps.
According to this invention the upper part of the lamp is not screwed into a
flange on the outside diameter of the oil container but the latter is entirely covered
by a top cast thereon but provided with a central depression chased with an
internal screw thread.
The upper part of the lamp is carried by a base plate on which the pillars are
rivetted and which is made with a flange above to receive the glass cylinder and
with a central hollow boss or flange beneath screwed outside to fit into the
depression of the oil container.
In this depression are arranged the wick tube and the regulator and the electric
contact maker, and on the base plate are fitted the electric terminals and wire for
lighting the lamp.
The said base plate is also made with a central opening surrounded by an
extinguishing tube, so that when the oil vessel is unscrewed the lamp will be put
out by drawing down the wick through this extinguishing tube.
By this construction of lamp a greater oil space is obtained in the same size of
oil container than has been usual, the lamp can also be very cheaply manufactured/
and is perfectly safe in use.
The extinguishing tube fixed upon a permanent base plate supporting the pillars
and the upper ring which carries the gauze top or chimney can be applied to other
constructions of lamp as it forms an important feature of my invention.
The base-plate for example may be provided with an external flange over the
wall of the cylindrical oil retainer.
The wick tube may also be flat or round.
The lamp is or may be locked by a vertical bolt passing through the base plate
and through the upper ring which carries the top part of the lamp, the bolt
being pushed up by the action of connecting the base plate to the top of the oil
container.
The said bolt comes behind a projection upon the flange of a screwed ring which
is screwed into the ring which is carried by the pillars and holds the gauze support
(or the chimney support) down upon the glass cylinder, and so prevents the said
screwed ring from being unscrewed.
The base plate is preferably held down upon the oil container by a catch similar
to the locking catch shewn 'and described by the Specification of Letters Patent
No. 8007 dated April 28th 1892.
Dated this 20th day of February 1893

page_text: COMPLETE SPECIFICATION.
Improvements in Miners' and other Safety Lamps.
I JOSEPH PRESTWICH of Irwell Park Eccles near Manchester in the County
of Lancaster, Manager, 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 the construction of that kind of miners' and other
safety lamps which can be lighted by electricity without opening the lamps...
My invention will be readily understood from the following description on
reference to the accompanying sheet of drawings, on which
Fig. 1 is a sectional elevation of a lamp constructed according to my invention,
Figs. 2 and 3 are horizontal sections through about the lines A A and B B (on.
Fig. 1) respectively.
According to this invention the upper part of the lamp is not screwed into a
flange on the outside diameter of the oil container a, but the latter is entirely
covered by a top a¹ cast thereon but provided with a central depression a' chased
with an internal screw thread, see Fig. 1.,
The upper part of the lamp is carried by a base plate b, on which the pillars c
are rivetted, and which is made with a flange 6 above. to receive the glass
cylinder d and with a central hollow boss or flange & beneath screwed outside to
fit into the depression as of the oil container a.
In this depression are arranged the wick tube e and the regulator f and the
electric contact maker g and on the base plate b are fitted the electric terminals i i
and wire for lighting the lamp.
The said base plate b. is also made with a central opening surrounded by an
extinguishing tube h so that when the oil vessel a is unscrewed the lamp will be
put out by drawing down the wick in the tubee through this extinguishing,
tube h.
By this construction of lamp a greater oil space is obtained in the same size of
oil container a than has been usual, the lamp can also be very cheaply manufactured
and is perfectly safe in use.
This combination of the extinguishing tube fixed upon a permanent base:
plate 6 supporting the pillars c and the upper ring k which holds in place or carries
the gauze top or the chimney, can be applied to other constructions of lamp as it
forms an important feature of my invention.
The base plate for example may be provided with an external flange over the
wall of the cylindrical oil retainer.
The wick tube may also be round as shown, or flat as shown in the drawings
annexed to the Specification of Patent granted to myself and The Protector Lamp
and Lighting Company Limited No. 18226 of 1890.
The lamp is or may be locked by a vertical bolt 7 passing through the base
plate b and through the upper ring k which carries the top part of the lamp, the
bolt being pushed up by the action of connecting the base plate to the top of the
oil container as seen by Fig. 1.
The said bolt comes behind a projection m³ upon the flange of a screwed ring m
which is screwed into the ring k which is carried by the pillars c and holds the
gauze support n (or the chimney support) down upon the glass cylinder d, and so
prevents the said screwed ring m from being unscrewed.
The base plate b is preferably held down upon the oil container a by a catch p
similar to the locking catch shown and described by the Specification of Letters
Patent No. 8007 dated April 28th 1892.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I.
claim is :-
1. The general construction and arrangement of electrically lighted safety
lamps substantially as hereinbefore described and illustrated by the annexed
drawings.
2. In a safety lamp the combination of a base plate carrying the glass cylinder
and pillars supporting the upper part of the lamp, and provided with a screwed
flange or its equivalent for attaching the same to the oil container, with means for
locking the two together and preventing the opening of the upper part of the
lamp until the two are separated substantially as herein before described and
illustrated by the annexed drawings.
3. In a safety lamp the combination of a sliding bolt with the fixed ring
supported by pillars, and projections or equivalent means for locking the screwed
ring which fixes the gauze or chimney support, the said sliding bolt being raised
by the attachment of the upper part of the lamp to the eil container substantially
as hereinbefore described and illustrated by the annexed drawings.
4. In a safety lamp the combination of a removable base plate supporting the
glass tube, the pillars and a fixed ring, with a screwed ring for holding the said
glass tube and the gauze or the chimney support in place substantially as herein-
before described and illustrated by the annexed drawings.
Dated this 30th day of September 1893.
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicant.