IMPROVEMENTS IN THE MANUFACTURE OF ELECTRIC ARC LAMPS
Year: 1883

page_text: LETTERS PATENT to Herbert John Allison, of the firm of Allison Brothers,
Patent Agents, of 41 Southampton Buildings, Holborn, in the County of
Middlesex, for an Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
ELECTRIC ARC LAMPS," communicated to him from abroad by William Baxter
Jun³, of Jersey City, New Jersey, United States of America,
PROVISIONAL SPECIFICATION left by the said Herbert John Allison at
the Office of the Commissioners of Patents on the 8th June 1883.
HERBERT JOHN ALLISON, of the firm of Allison Brothers, Patent Agents, of
41 Southampton Buildings, Holborn, in the County of Middlesex, "IMPROVE-
MENTS IN THE MANUFACTURE OF ELECTRIC ARC LAMPS," a communication to me
from abroad by William Baxter Junr, of Jersey City, New Jersey, United States
of America,
This invention relates to the manufacture of Air Tight Electric Lamps, and
consists in certain improvements in the construction of the casing in which the
regulator is enclosed, in the means used for securing the glass globe to the frame
of the lamp, and in the trunk or tubular connection between the casing and globe.
The objects of the invention are to gain access more readily to the regulator and
carbons; to adjust the latter without removing the globe or detaching any part of
the apparatus; and to prevent the access of the gases of combustion to the
regulator.
The improvement in the regulator casing consists in providing it with a tight
packing or joint for the passage of the carbon rod or holder, and in making a part
of the casing removable at a point where access is required to regulate or adjust
the automatic mechanism.
The improvement in the trunk consists first, in forming an opening in the side,
through which the said carbon rod may be reached, and the carbon removed or
adjusted, such opening having been fitted with an air tight cover: and secondly,
in connecting the upper end of the trunk (or tubular covering of the carbon rod)
to the regulator casing by legs, or by a perforated tube, so that gases escaping

page_text: from the trunk may be dissipated instead of entering the casing; the upper end
of the trunk being all closed except where the carbon rod enters, to exclude air
from the trunk.
This part of my invention also consists in a packing for the carbon rod: the
same being formed of a flexible disc fastened at the edges, and perforated at the
centre for the passage of the rod.
It also consists in providing the trunk with a cross-bar carrying supports for the
lower end of the glass globe or receiver, and with a screw sleeve for drawing the
cross-bar up on the trunk and in forming a seat faced with yielding packing upon
the lower end of the trunk, against which seat the globe is pressed and held when
the cross-bar is drawn up.
The means for holding the globe to the seat upon the end of the trunk are
adapted to disengage the globe with great facility to gain access to the carbons for
adjustment or renewal.
In one form of globe fastener, the trunk is formed with a screw thread and the
mouth of the globe is molded with a corresponding thread so as to be attached by
turning it around. A globe of this character, as well as in the modified kinds to
be described, would be open at only one end, and be fastened so as to hang down
from the lower end of the trunk.
In one modification, the mouth of globe is provided with an annular flange
having inclines formed at opposite points to engage bent lugs projected downward
from the trunk seat.
In another modification, the trunk is provided with an external flange at the
bottom; and the globe with a metallic ring to which two links are pivoted and
provided with means to fasten their upper ends upon the top side of the trunk
flange.
'
In another modification, two links are pivoted to the trunk at opposite sides,
above the packed seat against which the globe is fitted, and the lower ends of the
links are hooked and beveled to engage with an external flange at the mouth of
the globe. Such links may be pressed inward against the flange by a collar
surrounding the trunk and operating upon the middle or ends of the links.
In another modification, the globe is formed with a depression in its surface at
the bottom, and is held against the packed seat by a hanging stirrup.
The stirrup or strap is pivoted by its ends to opposite sides of the trunk seat,
and is made of elastic metal adapted to spring or yield where it passes beneath the
bottom of the globe; so that a bend or projection upon the stirrup may spring
into the depression in the bottom of the globe and press it toward the seat.
In another modification, I employ a cross-bar upon the trunk at the globe seat,
and a similar cross-bar and seat at the bottom end of the globe, which in this
construction is made equally open at each end; and connect the two cross-bars by
links and a pivoted lever acting as a toggle to draw the two cross-bars and their
seats together to clamp the globe between them.
In another modification, I provide a globe with an annular flange at the mouth
and form a bevel upon its lower side. I also provide the packed seat with several
lugs having set screws adapted to press upon the beveled side of the flange and
thus draw it tightly to the seat.
A further improvement, in the construction of the supports for the lower carbon,
when the latter are suspended from the packed seat inside a globe closed at the
bottom; consists in making the supporting rods tubular, and admitting air to them
from outside the globe.
Such air inlet may be provided with a stop cock, and the opening of the cock
serves to dilute the contained gases before detaching the globe after combustion ;
and thus prevent explosions and other injury resulting from such gases undiluted.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Allison in the Great Seal Patent Office on the
1st December 1883.
HERBERT JOHN ALLISON, of the firm of Allison Brothers, Patent Agents, of
41 Southampton Buildings, Holborn, in the County of Middlesex, "IMPROVE-
MENTS IN THE MANUFACTURE OF ELECTRIC ARO LAMPS," a communication to me
from abroad by William Baxter, Jun, of Jersey City, New Jersey, United States
of America, 9.
;
This invention relates to certain improvements in the manufacture of air-tight
electric lamps, and consists in certain improvements, in the construction of the
casing in which the regulator is enclosed, in the means used for securing the glass
globe to the frame of the lamp, and in the trunk or tubular connection between the
casing and the globe.
The objects of the invention are, to gain access more readily to the regulator
and carbons; to adjust the latter without removing the globe or detaching any
part of the apparatus; and to prevent the access of the gases of combustion to the
regulator.
In the drawing annexed, Fig. 1 is a connected view of an arc lamp provided
with certain of my improvements, the drawing being in vertical section, at the
centre line, where it is shaded. Fig. 2 is a similar view of a lamp showing an
alternative mode of clamping the globe to the trunk. Fig. 3 is an inverted plan of
the seat G in Fig. 2 against which the globe is held. Fig. 4 is a plan of the lower,
seat G shown in Fig. 1.
Figs. 5 to 13 inclusive represent modified forms of the fastening devised for the
globe, the trunk B' being only partially shown in each.
Fig. 14 is an external view of a lamp having a door formed in the side of the
trunk to remove and insert carbons; the casing B being partly omitted. Fig. 15
is a central vertical section of a lamp similar to that in Fig. 14, excepting the means
for gaining access to the trunk.
My improvements are adapted to an electric lamp in which the arc is enclosed in
an air-tight glass receiver, or in one constructed of metal and having a glass panel
in the side, the carbons, in either case, requiring to be replaced from time to time
when they are consumed.
The trunk B₁ referred to herein is used to enclose the carbon rod b and the
clamp 62, the latter having an extended motion during the consumption of the
carbon and thus requiring a long tubular covering, as shown in Figs. 1, 2, 14,
and 15.
My improvements include the enclosing of the regulator in a tight casing B, the
regulator shown herein at Fig. 1 consisting in certain feed rollers a, a, actuated by
automatic magneto-electric devices and operating to propel the upper carbon rod b
as required; but any regulator may be employed.
The improvement in the regulator casing is shown in Fig. 15 and consists in
providing it with a tight packing or joint at the bottom for the passage of the
carbon rod or holder, and in making a part of the casing removable at a point
where access is required to regulate or adjust the automatic mechanism, as by the
screw joint B³.
The improvement in the trunk is shown in Figs. 14 and 15 and consists first, in
forming an opening in the side through which the said carbon rod may be reached,
and the carbon removed or adjusted, such opening being fitted with an air-tight
cover, and secondly in connecting the upper end of the trunk (or tubular covering

page_text: of the carbon rod) to the regulator casing by legs or by a perforated tube, so that
gases escaping from the trunk may be dissipated instead of entering the casing;
the upper end of the trunk being all closed except where the carbon rod enters,
to exclude air from the trunk,
The globe or air-tight enclosure of the carbons, is lettered C, the upper carbon C¹,
the lower one C, the lower carbon holder N, the seat at the lower end of the trunk
against which the globe C is clamped, G; the lower seat in Fig. 1, G'; the screws
for holding the carbon holder N to the same, e; and the foot of the holder d.
In Figs. 1 to 4, a washer of yielding material is shown in contact with the seats
G and G¹, and secured thereto by a flange as d¹.
Figs. 14 and 15 show the casing B united to the trunk B¹ by legs H, the top of
the casing being closed by the flanges and the rod b passing through a packing
formed of a flexible washer b' held fast at the edges and fitted snugly around, the
carbon rod b. As the pressure is equal upon opposite sides of these packings, there
is no tendency to leakage, and the rod 6 moves freely through it when operated to
feed the carbon.
A similar packing may be applied to the bottom of the casing B as in Fig. 1; or
the rod pass therefrom through a snugly fitting hole, as in Fig. 15.
The provision of the open space between the legs Hat the top of the trunk
prevents the intrusion of the gases of combustion into the regulator, where they
cause corrosion of the mechanism; and also enables the operator to manipulate the
carbon rod b while the lamp is in operation without opening the closed covering of
the lamp at any point.
In Fig. 14 the trunk B¹ is shown constructed with a door I in the side secured
by hinges p', and by any suitable catch adapted to hold it tightly shut against a
seat, to which it is fitted in such manner as to exclude the air. In Fig. 15 the
trunk is divided at the middle of its length, and the upper part is made of different
size from the other, so as to slide inside of it; the two being fitted together with a
screw thread, so that when the upper half is turned around by the operator, it is
unscrewed and slid down inside the other to expose the carbon C and clamp b².
With the latter construction, the lower end of the trunk is formed with an inside
flange g, which is connected with the flanges by rods f¹, so as to hold the seat G
and globe in their relation to the regulator, when the trunk is thus divided
transversely.
The rods are shown in Figs. 2 and 15 extended downward inside the globe C, to
carry the lower carbon holder N, and a similar provision for the support of the
lower carbon is presupposed in the apparatus shown in Figs. 5 to 13 inclusive,
although not shown therein, as the Figures relate merely to the globe clamping
devices.
The means for holding the globe to the seat upon the end of the trunk are
adapted to disengage the globe with great facility to gain access to the carbons for
adjustment or removal.
Fig. 1 shows the means of clamping a globe which is open at both ends, the
lower clamping seat being formed upon a cross bar F, connected with another cross
bar E which is movably attached to the trunk B by a hub H. This hub is fitted
to slide upon the body of the trunk B¹ above an enlargement B' provided with a
screw thread c; and a tubular nut H, fitted to the thread, serves when turned by
the hand of the operator, to draw the cross bars E and F upward and clamp the
globe C between the seats G and G¹. In like manner, the lowering of the cross
bar E by unscrewing the nut H serves to lower the bar F and release the globe so
that it can be readily removed. The packing & applied to the seats may be made
of asbestos and secures a close joint, without costly fittings, at the atmospheric
pressure to which it is subjected, no effort being made to maintain different
pressures inside and outside the globe, as the latter is used merely to prevent a
fresh supply of oxygen from reaching the carbons after that first contained in the
globe is consumed.
Fig. 2 shows a means of clamping the globe to the seat G, when the former is

page_text: closed at the bottom, to be sustained entirely by its upper end. The globe is
formed with an external flange i at its mouth, bevelled upon the lower side, and is
held to the seat by screws h¹ fitted in lugs h around the edge of the seat; the
bevel serving to draw the flange into close contact with the packing d. The side
of the flange next the packing may also be formed with a wedge-shaped ridge to
penetrate the packing more easily. By slacking the screws h¹ the globe can be
readily removed for cleaning or replacing the carbons. One of the rods f shown
in Fig. 2 is represented as hollow and extended through the metal above the
seat G so as to be provided with the cock w by which air may be admitted
through the rod to holes v near its lower end, by means of which air can be
introduced into the lower part of the receiver, prior to removing the globe C from
its seat. As the carbonic gases generated by the arc, are very heavy, they lie
chiefly at the lower part of the receiver, and sometimes have caused an explosion,
when the latter are removed from their seats.
In another modification shown in Fig. 6 I employ a cross bar like E in Fig. 1
upon the trunk at the seat G and a similar lower cross bar like F and seat G₁ for
the bottom of the globe, which is formed open at both ends as in Fig. 1; and
connect the two cross bars by links o and a pivoted lever D acting as a toggle to
draw the cross bars and their seats together to clamp the globe between them. The
lever is pivoted to the links o by pins n at opposite sides of the globe, and is
provided at each side, with a regulating screw m which operates on the pins n to
adjust the pressure applied to the globe.
The handle is shown at D' in its unlocked position, when the lower seat G¹ would
be lowered to permit the removal of the globe.
In Fig. 5 and in Figs. 8 to 15 the globe is shown with an opening or mouth
only at the upper end. The views to Fig. 13 representing various modifications
of the means I have devised for fastening the globe removably to the seat G.
In one modification shown in Fig. 5 the globe is formed with a depression k
in its surface at the bottom, and is held against the packed seat by a hanging
stirrup.
The stirrup or strap I is pivoted by its ends at j to opposite sides of the trunk
seat, and is made of elastic metal adapted to spring or yield when it passes
beneath the bottom of the globe, so that a bend or projection upon the stirrup, may
spring into the depression in the bottom of the globe and press it towards the
seat. A knob is provided to draw the bend out of the recess k and the globe is
then entirely loose for removal.
In another modification shown in Fig. 8 the trunk B¹ is formed with a screw
socket B3 around the seat G and the globe is provided with a screw thread C³ at its
mouth by which it can be readily held to the seat.
In another, shown in Fig. 9, two links K are pivoted to the trunk at opposite
sides; above the packed seat G against which the globe is fitted, and the lower.
ends of the links are hooked and bevelled, to engage with an external flange at
the mouth of the globe. Such links may be pressed inward against the flange by
a collar K surrounding the trunk and operating upon the middle or ends of the
links, or they may be formed as in Fig. 10 as levers having arms Js extending
upward beyond the pivots k¹ upon opposite sides of the trunk; and the trunk may
be provided with a sliding cone J fitted to the upper ends of the levers and
operating to press the lower ends of the links inward against the flange i upon
the globe. The cone may be formed with a hub or collar J¹ to move it readily by
hand.
In another modification shown in Fig. 11 the mouth of the globe is provided
with an annular flange C having inclines r' formed at opposite points to engage
bent luger projecting downwards from the trunk seat. Notches are formed in
the flange to admit the lugs, and the globe is held to the seat by turning the
inclines forcibly against the hooks.
In another, shown in Figs. 12 and 13, a metallic band M is made in halves and
clamped to the neck of the globe, and formed with ears to which links Lare

page_text: pivoted at k². The seat G is formed with an annular depression or groove on its
upper side at q and the globe is held to it by curving the links inward over the
seat and locking their upper ends to the groove, either by toggle levers L³ pivoted
to the tops of the links at l as in Fig. 12; or by set screws R as in Fig. 13.
Fig. 7 shows a means of gaining access to the carbons through an opening in
the receiver itself, which in this case is not formed of a glass globe, but of a square
metallic box, having a door P¹ hinged at one side, and tightly closed by screws v.
A glass panel P2 is shown in the door to emit the light and similar panels may be
formed in the other sides if desired.
Some of the details of construction may be changed, without affecting the
operation desired; thus the desired open space in the top of the trunk may be
secured without the use of the legs H shown in Figs. 14 and 15 by making
apertures in the sides of. the trunk itself at that point and inserting the flange a
provided with a tight packing for the rod b.
Having thus set forth the nature and objects of this invention, I claim the same
as follows:-
1st. In an electric lamp, two carbons, an automatic regulator for the same, and a
supporting frame, combined with a practically air-tight receiver to enclose the
contiguous carbon points, and a slip-joint or packing through which the moving
carbon may enter said receiver without permitting the gases to pass to the
regulating mechanism.
2nd The combination with the casing B and trunk or tube B¹ connected air-
tight thereto, of a packing b¹ at the bottom of the casing, as in Fig. 1, to prevent
gases from entering the casing around the rod b.
3rd. The combination with the trunk B', as in Figs. 14 and 15, of an opening
through the trunk to reach the carbon clamp 62 and a tight cover for the opening
as door I or tube B' to close said opening air-tight.
4th. The combination with the trunk B¹, as in Figs. 14 and 15, of a partition
flanges provided with a hole for the passage of the carbon rod b, and an open
space between the partitions and the casing B, as between the legs H, to permit
the manipulation of the rod b when the lamp is in operation.
5th. The flexible packing washer b¹ fitted to make a tight and easy joint around
the carbon rod b as shown in Figs. 1 and 15.
6th. The combination with the trunk B¹, seat G and globe C, of the means herein
shown and described for holding the globe removably to the seat.
>
7th. The combination with the seat G of a packing washer d formed of asbestos
or other suitable material, and held to the seat by a ring d' secured over a part of
the packing, as shown in Figs. 1, 2, 3, and 4.
8th. The combination with the casing B, trunk B' and seat G, of the rods ƒ, ƒ',
suspending the lower carbon holder N inside the globe, as shown in Figs. 2
and 15.
In witness whereof, I, the said Herbert John Allison, have hereunto set my
hand and seal, this first day of December in the year of our Lord one thousand
eight hundred and eighty-three.
HUDDLDT T ATTISON
Gal