Year: 1887

page_text: Date of Application, 11th Jan., 1887.
Specification Accepted, 11th Feb., 1887.
I, HERBERT JOHN ALLISON, of 52 Chancery Lane, London, in the County of Middle-
sex, Patent Agent, 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 :-
My invention relates to lamps and consists in the improvement herein described
and claimed.
The general construction of an argand lamp to which my improvement is applied
does not differ materially from that in common use, as will be scen by the accompany-
ing drawing forming a part hereof in which,
Figure 1 is a vertical, central section of a lamp embodying my improvement; and
Figure 2 is a plan of the same.
A is the body as fount; B is the wick-tube open at the top and bottom, secured to
the bottom of the body A, and extending upward above the top of the same C is the
cylindrical wick on the wick-tube; b is the wick-shifter, consisting of a band or ring
surrounding the lower end of the wick, fitting snugly to it, and made to take hold of
it by means of spurs or otherwise, so that when the ring is raised or lowered it will
carry the wick with it. E is a bar or rod that is connected to the ring & by an arm b².
The bar extends upward above the top of the body A, through a radial slot or
opening e in the said top. This slot e extends from the interior of the neck of the
lamp outward far enough to contain the said bar and permit it to move up and down
freely in it; the slot also permits the arm 2 to pass through it, so that the wick-
shifter with the arin and bar E may be introduced into, and removed from the lamp
at pleasure. By taking hold with the hand of the upper end of the bar E and lifting
it up or pressing it downwards the wick will be raised or lowered to adjust it for
burning, or removal from the lamp.
But in the movement of
This lamp, so far as I have now described it is not new.
the wick shifter & by means of the bar E as described, a difficulty is experienced
which it is the purpose of my improvement to remedy.
It will be observed that the bar E is held and supported in the slot e only on its sides,
and possibly on its outer edge, it being left free to move towards the wick-tube B;
and this is necessarily so, as the slot e must be unobstructed between this said bar

page_text: and tube to permit the arm 2 to pass through it. When the top end of E is pushed
over towards B, (and this is very likely to occur whenever the bar is pulled upward or
pushed downward) the band is tilted on the wick-tube and thereby made to bind
thereon, and thus the easy and accurate adjustment of the wick is interfered with.
To obviate this difficulty, I provide ways for guiding the bar E that insure the
vertical movement of the bar parallel to the tube B. To this end I secure in the
radial slot e two guide plates e, between which the bar runs. These plates extend
above (and preferably also below) the top of the fount A sufficiently to furnish a
suitable support to the said bar. In the inner faces of these plates (one or both) are
made vertical grooves or ways and on the said bar, (on one or both sides) guide ribs e
fitted to run in said ways, so that the bar will be prevented while moving up and
down, from being tilted over towards the tube B, thereby preventing the ring from
binding on tube B, and causing it to slide truly and freely thereon while the slot e is
left unobstructed to permit the arm 2 to pass through it, in putting in and taking out
the wick and wick-shifter.
et is a rack formed in the bar E, and is a toothed pinion the shaft of which is
journaled in the plates e', the pinion meshing with the rack. On said shaft is a milled
heade for convenient rotation of the pinion.
When this rack and pinion are employed to raise and lower the bar E the action of
the pinion on the rack tends to thrust the bar away from the pinion and out of parallel
to the tube B, and thus cause the band to bind on the tube. The described ways
and ribs hold the bar against this thrust.
The said guide ways and ribs are preferably triangular in form, as shown in the
drawings; but they may be of any other suitable form. By these means the move-
ment of the said bar E and the ring accurately parallel to the tube 13 is insured,
and the binding of said ring on the tube is prevented, while as before stated the slot e
is left unobstructed to permit the arm 1 to pass through it, in putting in and taking
out the wick.
I prefer to form a guide rib on each side of the bar E and a corresponding groove
in each of the guide plates; but it is obvious that a rib on one side of the bar and a
corresponding groove in one of the plates, the bar bearing against the opposite plate
will serve the purpose.
Having now particularly described and ascertained the nature of my said invention,
and in what manner the same is to be performed, I declare that what I claim is :—
1st. In combination in an argand lamp, the fount provided with a slot e, the guide
plates el secured on the top of the fount, one on each side of said slot, and provided
one or both with a groove e, the wick tube B, the wick-shifters on said tube and
fitted to the same and to hold the wick C, the bar E connected by an arm &² to the
wick-shifters and extending upward above the top of the fount between the plates e
and provided on one or both sides, with a rib fitted to slide in said grooves, whereby
said bar and wick-shifter in their vertical movement are held parallel to the tube B,
while the slot e is unobstructed to permit the wick-shifters arm and bar to be introduced
into and removed from the lamp, all as and for the purpose described.
2nd. The combination, in an argand lamp, with the fount A, provided with the slot e,
the guide plates el secured on the top of the fount, one on each side of said slot, and
provided, one or both, with a groove ², the wick-tube B, the wick-shifter on said
tube, the bar E connected by an arm to the wick-shifter, and extending upwards
above the top of the fount between the plates e¹ and provided on one or both sides,
with a rib e fitted to slide in groove e, of the described rack and pinion, adapted to
raise and lower the said bar and wick-shifters, all as and for the purpose described.