Improvements in Safety-lamps.
Year: 1894

page_text: Date of Application, 14th Nov., 1894-Accepted, 2nd Feb.,
1895
Improvements in Safety-lamps.
We, ROBERT HAY, HUGH TOAL, and THOMAS LOWTHER, of Mount Pleasant,
in the County of Westmoreland, and State of Pennsylvania, United States of
America, Gentlemen, 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 improvements in lamps, and to that particular class
thereof known as safety-lamps and employed by miners and others who frequent
chambers and other places where explosive gases are present.
The objects of our invention are to produce a lamp that may be safely employed
in such places, and which is of cheap, simple, and durable construction, and whose
parts may be readily constructed, assembled and replaced, and which is capable of
being locked securely before entering the dangerous places, whereby an accident
from an intentional or accidental disconnection of the parts may be avoided.
Other objects and advantages of the invention will appear in the following
description, and the novel features thereof will be particularly pointed out in
the claims.
Referring to the drawings:
11
Fig. 1 is a perspective view of a lamp embodying our invention.
Fig. 2 is a vertical longitudinal sectional view of the same.
Fig. 3 is a horizontal sectional view through the base-ring.
Fig. 4 is a perspective view of the upper chimney ring and connected parts,
detached.
Fig. 4^, is a partial vertical section of a lamp of modified construction.
Fig. 4B, is a detail view of the enlarged section of a portion of the base ring,
ventilating-ring and contiguous parts.
Fig. 5 is a detail view of the ventilating-ring.
Fig. 6 is a detail in perspective of the reservoir-cap, burner-ring, the burner, and
its fastener, the parts being separated.
Fig. 7 is a detail view of the locking device whereby the base-ring and the
burner are held from independent rotation, a portion of the casing being broken
away to show the latch.
Fig. 8 is a detail view in perspective of the key.
Like numerals of reference indicate like parts in all the figures of the drawings.
In the practice of our invention we provide the reservoir 1, with a metal cap 1º,
the same having at its center a reduced opening 2, in which is seated and secured
the burner-ring 3. The cap 1ª is provided upon its upper side with a surrounding
bead or flange 4 and within the same with inclined teeth 5, a plurality of which are
located at intervals. The burner-ring 3 is provided with a central opening 6,
which is surrounded by a circular flange 7. Half-threads 8 are formed at opposite
sides of the periphery of the burner-ring 3, and similar half threads 9 are formed
at the upper edge of the circular flange 7.
Within the flange 7 is formed a horizontal annular shoulder 10. A burner-
disk 11 is seated removably on the shoulder 10 and fits within the annular flange 7,
and carried by and projecting above and below the plane of said disk is a burner
tube 12. A spring-yoke 13 has a central opening 14, which fits over the tube, and
the ends of the yoke are turned down to form engaging fingers 15. These engaging
1

page_text: fingers 15 are designed to pass through the notches formed between the half-
threads 9 and by giving the yoke a turn the aforesaid fingers will engage under the
notches and bind against the threads, thus locking the disk and tube upon the
flange 7.
Removably seated within the annular bead 4 of the reservoir-cap 1, is a base-
ring 16, and said base-ring is provided upon its interior with diametrically opposite
lugs 18 to removably interlock with and bind against the underside of the half-
threads 8 of the burner-ring 3. At one side of the base-ring we locate spring-
latch 19, the same being seated in a recess formed in the base-ring and having its
operating end normally depressed and designed to engage with the inclined teeth 5
formed in the upper side of the reservoir-cap 1º, so that by screwing the base-ring
upon the reservoir-cap and the latch engaging with the teeth any attempt to remove
said ring and the parts carried thereby and hereinafter described will be success-
fully resisted, and it will be necessary in order to effect a removal to operate the
latch or elevate the same into its recess and out of engagement with the aforesaid
teeth. Such elevation we accomplish in the present instance by means of a key 20,
which is bifurcated at its inner end so as to engage over a web 21, with which the
pintle of the latch is provided. This key is provided with a parallel-sided
shoulder 20, to fit in a parallel-sided seat 20%, adjacent to the web 21.
slot 20, of the key is engaged with the web 21, the shoulder of the key is out of
alignment with said seat, and when the key is turned to bring its shoulder 20ª, into
alignment with said seat the latch is raised out of engagement with the teeth 5, and
when the key is forced inward to engage the shoulder 20 with the seat said latch
is locked out of engagement with the teeth and the base-ring is free to move
independently of the cap 1*.
When the
It will be understood that any other form of lock may be employed such being a
mere detail to which we do not limit our invention. The base-ring is further
provided entirely around the same with a series of transverse air-inlets or venti-
lating openings 22, and within the ring we locate a removable ventilating-ring 23
which is also provided with a series of transverse openings that register with an
annular groove or chamber 24 formed on the inner side of said ring 23. This chamber
or recess is covered by a reticulated or gauze-wire covering 25, and the ring is
surmounted preferably by an asbestos packing 26 cut in the form of washers. This
ventilating-ring comprises an upper annular disk 27 provided at its inner periphery
with an upstruck flange 27", thereby forming a seat 27b; an annular openwork
frame 27 provided in its sides with a series of slots 27d; and a lower ring 27°, said
parts being secured together by the vertical screws 27'. The gauze-wire
covering 25 is arranged to cover the inner side of the openwork-frame and is
arranged at its edges between the upper disk 27 and the lower-ring 27 and the
interposed openwork frame. This ventilating ring is reduced or tapered slightly
toward its lower side to fit in the circular opening in the base ring, and the
flange 27 which is arranged around said opening in the base-ring combines with the
upper surface of the annular disk 27 and its upstanding flange 27" to form the seat 27ª.
This ventilating-ring it will be understood encircles the flanged opening 7 of the
burner cap 3, and admits air to the burner, whereby the brilliancy of the light is
increased in a manner obvious.
Arranged above the base-ring a suitable distance is the cap-ring 28, the same
being supported upon the base-ring and connected thereto by means of a series of
intermediate posts or tie-rods 29. This ring 28 is interiorly threaded as shown
at 30, and threaded therein is a holding-ring 31 provided at its upper side with
finger-holds 32. Mounted upon the seat 27, is the cylindrical glass chimney 33,
an asbestos washer 26 being interposed between its lower edge and the seat, and the
holding ring 31 is arranged to maintain said chimney in place, a similar asbestos
washer 34 being interposed between the under surface of the holding ring and the
upper end of the glass chimney. Formed upon the upper side of the cap ring 28 is
an annular flange 35 provided at its opposite sides with half-threads 36. Resting
upon the upper surface of the upper asbestos washer and fitting in an annular

page_text: cover 39º
groove 37 in the under side of the holding ring is the flange 38 at the lower end of
the reticulated ventilating chimney 39, said chimney extending upward through the
opening in the holding ring and being provided at its upper end with a removable
A crown-ring 39 encircles the ventilating chimney and is provided
upon its inner side with lugs 39 arranged diametrically opposite each other and
designed to engage and bind against the under sides of the half-threads on the
Hange of the cap ring. Attached to the crown-ring is a ventilating cap 39, having
the ventilating openings 39º, and provided at its upper end with the suspension-
ring 391.
It will be understool that the cap-ring 28 and the holding ring which is fitted
therein combine to form a chimney-ring whereby the upper end of the glass chimney
is held in place.
Substituted for one of the tie-rods 29 between the base and cap-rings of the
chimney is a swiveled locking post 40, the same having extending therefrom
adjacent to its ends L-shaped locking arms 41. The locking arm 41 at the lower
end of the post is designed when the post is oscillated in one direction to engage
with a vertical groove 42 formed in the exterior of the base-ring and so as to lie flush
therewith, and the upper arm is designed to engage in grooves 43 formed in the
edge of the ring 28 and the crown-ring 39b, so that as will be obvious the crown-
ring is locked upon the cap-ring 28 and the lower end of the lower locking arm
being engaged by the bead or flange 4 of the cap of the reservoir, the said post is
prevented from oscillating and permitting of any movements of these parts as will
allow of a separation.
Thus it will be seen that our lamp may be entirely disconnected, the parts
cleaned and replaced without the use of any tools. When the lamp has been
lighted and provided with oil it is automatically locked by the latch, and can only
be opened by the insertion of the key with which in mines only an authorized
person is provided, so that the careless opening of the lamp whether intentional or
otherwise by a person in a dangerous chamber or other place cannot take place
and hence explosions are avoided. Any gas that does enter the lamp must pass
through the ventilating openings which surround the burner and hence is consumed
as fast as it enters, so that no dangerous explosions can occur.
Our lamp operates upon the same principle as the well-known safety-lamp, and
hence requires no specific description.
In the modified form of our invention which is shown in Fig. 4ª, the cap-ring is
provided with a flange 44 having opposite half-threads 45, and the crown-ring 46
is provided with opposite lugs 47 for engaging said half-threads. In this form of
the invention the base-ring 48 is provided with opposite half-threads 49 which are
adapted to be engaged by lugs 50 on opposite sides of the ventilating ring, and the
glass and ventilating chimneys are inserted from below, the ventilating chimney
being passed up through the base-ring and cap-ring until the flange at its lower
end bears against the seat 51 in the under surface of the cap-ring, the glass chimney
being then inserted to hold said flange of the ventilating-chimney in its place in the
seat, and the ventilating ring being then inserted and having its opposite lugs
engaged with the half-threads 49 of the base ring. The burner-ring is subsequently
applied in the manner hereinbefore described in connection with the preferred form
of our invention.
We do not limit our invention to the precise details of construction herein shown
and described but hold that we may vary the same to any degree and extent within
the knowledge of the skilled mechanic.
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 safety-lamp, the combination with a reservoir cap and a burner-ring
supported thereby, of a base-ring seated upon the upper side of the reservoir-cap
around the burner-ring and removably attached thereto, a chimney-ring spaced

page_text: from and connected to the base-ring and comprising an outer cap-ring and an inner
detachable holding-ring provided in its underside with a seat, ventilating devices
supported upon the chimney-ring, a ventilating ring removably fitted within the
base-ring and provided in its upper side with a seat, said base-ring and the
removable ventilating ring being provided with registering horizontal perforations,
and a chimney interposed between and fitted at its extremities in the seats of the
ventilating ring and the holding-ring, and held by the latter in such position,
substantially as specified.
2. In a safety-lamp, the combination with a reservoir-cap and a burner-ring
supported thereby, of a base-ring seated upon the reservoir-cap around the burner-
ring and detachably secured to the latter, said burner-ring being provided at its
inner periphery with an upstanding flange, a ventilating-ring fitting removably
within the burner-ring and held from downward displacement, said ring being
provided at its inner periphery with an upstanding flange corresponding with that
on the inner periphery of the burner-ring and combining with said flange and the
upper side of the ventilating-ring to form a seat, a chimney-ring spaced from and
connected to the base-ring and provided in its under side with a seat, ventilating
devices supported upon the chimney-ring, and a chimney interposed between and
fitted at its extremities in the seats of the chimney-ring and ventilating-ring,
substantially as specified.
3. In a safety-lamp, the combination with a reservoir-cap and a burner-ring
supported thereby, of a base-ring seated upon the reservoir-cap around the burner-
ring and removably attached to the latter, a chimney-ring spaced from and
connected to the base-ring and comprising a fixed cap-ring and a holding-ring
removably fitted and secured to the cap-ring, said holding-ring being upwardly
removable, a ventilating ring fitted within the base-ring, means for preventing the
downward displacement of the ventilating-ring, a chimney seated at its lower end
upon the ventilating-ring and fitting at its upper end in said cap-ring whereby the
removable holding-ring may be arranged to bear upon the upper end of the chimney
and hold the same in its seat on the ventilating-ring and ventilating devices
supported upon the chimney-ring, substantially as specified.
4. In a safety-lamp, the combination with a reservoir-cap and burner-ring
supported thereby, of a base-ring seated upon the reservoir-cap around the burner-
ring and removably secured to the latter, a ventilating-ring seated in the base-ring,
a chimney-ring spaced from and connected to the base-ring and comprising a fixed
cap-ring and a removable holding-ring threaded within the cap-ring, a chimney
seated upon the ventilating-ring and fitted at its upper end in the cap-ring in the
path of said holding-ring, whereby when the latter is adjusted downwardly it
engages and secures the chimney in its seat, and ventilating-devices supported by
the chimney-ring, substantially as specified.
5. In a safety-lamp, the combination with a reservoir-cap and a burner-ring
supported thereby of a base-ring seated upon the reservoir cap around the burner-
ring and removably secured to the latter, said base-ring having a downwardly
tapered or reduced inner periphery, a downwardly tapered or reduced ventilating
ring fitted snugly within the inner periphery of the base-ring whereby downward
displacement is prevented, a chimney-ring spaced from and connected to the base-
ring and comprising a fixed cap-ring and a removable and adjustable holding-ring
fitted in the cap-ring, a chimney seated upon the ventilating-ring and arranged at its
upper end within the cap-ring in the path of said removable and adjustable
holding-ring, and ventilating devices supported by the chimney-ring, substantially
as specified.
6. In a safety-lamp, the combination with a reservoir-cap, and a burner-ring
supported thereby, of a base-ring detachably secured to and surrounding the
burner-ring, a ventilating ring seated within the base-ring, a chimney-ring spaced
from and connected to the base-ring and comprising an outer fixed cap-ring and an
inner removable and adjustable holding-ring fitted within the cap-ring, said holding-
ring being provided at its under side with an annular seat, a glass chimney seated

page_text: at its lower end upon the ventilating ring and fitted at its upper end within the
cap-ring in the path of said adjustable holding-ring, a reticulated chimney fitted at
its lower end within the holding-ring and provided with a flange arranged in said
seat of the holding ring and between the same and the upper end of the glass
chimney, and a ventilating cap supported by the cap-ring, substantially as specified.
7. In a safety-lamp, the combination with a reservoir-cap and a burner ring
supported thereby, of a base-ring removably secured to and surrounding the burner-
ring and provided with radial perforations, a ventilating-ring seated within the
base-ring and comprising upper and lower annular plates, an interposed open-frame
having lateral slots which communicate with the radial perforations of the base-ring,
and a wire-gauze covering arranged upon the inner periphery of the ventilating-ring
and inserted at its upper and lower edges between the upper and lower annular
plates and the said frame, said annular plates being secured to the frame to hold
the wire-gauze covering in place a chimney-ring spaced from and connected to the
base-ring and having a removable part or member, a chimney seated at its lower
end upon the ventilating-ring and at its upper end in the chimney-ring and secured
in place by means of the removable part or member of said chimney-ring, and
ventilating-devices supported by the chimney-ring, substantially as specified.
8. In a safety-lamp, the combination with a reservoir-cap, a burner ring carried
thereby, a base-ring, a half-thread and lug connection between the base-ring and
the burner-ring, a chimney-ring spaced from and connected to the base-ring, a
chimney interposed between the planes of the base-ring and chimney-ring, a
crown-ring seated upon the chimney-ring, a balf-thread and lug connection between
the crown-ring and the chimney-ring, a ventilating-cap carried by the crown-ring,
and a reticulated ventilating chimney carried by the chimney-ring within the
chimney-cap, of a swiveled latch carried by the base-ring and chimney-ring and
provided at its upper end with an arm to engage registering notches in the
chimney-ring and crown-ring and at its lower end with an arm to lie in a groove
in the base-ring and engaging an upstanding peripheral flange on the reservoir-cap,
a pivotal pawl carried by the base-ring to engage teeth on the reservoir-cap, a we'
attached to the pawl and arranged in an exterior socket on the base-ring, s
socket being provided with a diametrical seat, and a split-key to fit in the socket
and engage said web, and provided with a transverse shouldered portion to engage
the diametrical seat of the socket when the key has been turned sufficiently to
disengage the pawl from the teeth, substantially as specified.
Dated this 14th day of November 1894.
W. P. THOMPSON & BOULT,
Agents for the Applicants.