Apparatus for Making Mica Chimneys or Tubes for Gas Burners.
Year: 1895

page_text: Date of Application, 30th May, 1895
Complete Specification Left, 15th Oct., 1895-Accepted, 7th Dec., 1895
PROVISIONAL SPECIFICATION.
Apparatus for Making Mica Chimneys or Tubes for Gas Burners.
I, EUSTACE SLOPER, of 20 King William Street, City of London, Engineer,
do hereby declare the nature of this invention to be as follows:--
This invention relates to apparatus for making mica chimneys or tubes for gas
burners, and includes a method or process and means for binding the ends and
connecting the seams by metallic bands and strips.
The apparatus consists of hinged jaws with hollow meeting faces, into which the
mica in sheet form can be arranged after being placed on the top and under clips
which locate the sheets squarely with each other.
A press head is arranged above the jaws and after the sheets are in position
an Z shaped strip of metal is pushed along to enclose the central overlapping
edges of the sheets, the pressure then applied fixes the strip securely to lock the
mica edges therein.
The jaws slide outwardly and are then opened for the centrally joined or
connected edges with the strip to be folded from the centre to follow the contour
of the hollow in the jaws, the jaws are then closed and slid back with the opposite
edges of the mica sheets exposed ready for the reception of a second Z strip of
metal and the press head acted upon to secure those elges.
The jaws can be provided with closing springs if desired.
The fixed frame has a mandrel or tube core which occupies a position in the
hollows of the jaws and forms a bed for resisting the pressure of the head.
In some cases rivetting is essential, and for this purpose I prefer to employ
Lshaped pins which can be forced through or into holes previously punched or
perforated in the metal strips, this punching or perforating may be effected
simultaneously by the press bead with the pressure if such head be provided with
the necessary appliances.
A spring plate can be applied to the under surface of the press head to hold
the strip firmly yet temporarily while the punching or perforating is being effected
and to allow the press head to retire with the punches or perforators without lifting
the strip.
The mandrel is or may be eccentrically fitted so that a partial rotation can be
given to it for bending the exposed legs of the L pins which the pressure clamps
home, the mandrel having a longitudinal slot or apertures for the first reception
of the pins legs.
The mica tube thus formed has to be protected at the annular edges, and for
this purpose I employ U shaped rings or annular ferrules which when slipped on
are rolled into close contact with the mica and then by other shaped pins are
fixed, the pins preferably also going through the ends of the strips.
If the mica slects are not sufficiently long to form a tube of the desired length,
such tube could be made up of smaller sheets and might necessitate intermediate
bands which could be slipped on or over the meeting edges, but in most cases the
edges of the mica sheets could be overlapped and their connection with the Z strips
would be sufficient.
Dated this 30th day of May 1895.
H. GARDNER,
Patent Agent, 166 Fleet Street, London,
Agent for the said Eustace Sloper.

page_text: Apparatus for Making Mica Chimneys or Tubes for Gas Burners.
I, EUSTACE SLOPER, of 20 King William Street, City of London, Engineer,
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 apparatus for making mica chimneys or tubes for gas
burners, and includes a method or process and means for binding the ends and
connecting the seams by metallic bands and strips.
My invention is clearly shown in the annexed drawings.
Figure 1 face view of a complete machine.
Figure 2 a part sectional plan.
Figure 3 sectional detail with the movable bed in one position, such as when
bending the mica into tube form.
Figure 4 similar elevation with the tube jaw closed and the S rib a in position
waiting for the press head to descend to shut the seam.
Figure 5 is a side and edge view of the first ribbing and connecting four sheets
of mica.
Figure 6 elevation of mica tube with both ribs in position and the mica cramped
in place in said ribs.
A is the bed plate. B the bridge in the boss C of which a screw D passes
provided with a swing wheel or arms E for up and down motion of the "force" F
which move in guide bearings G, G. This "force" has a bottom plate H. and
springs I, I, for holding the strip firmly yet temporarily for the pressure and also
while punching or perforating is being effected and to allow the press head to retire
with the punches or perforators without lifting the strip.
J is a sliding bed movable in V grooves of the bed plate A by the handle K in
order that it can be drawn outwardly to a fixed distance to receive the first rib and
the sheets of mica in the flat condition, and then to be pushed back under the
"force" for the first pressure which unites the mica sheets in the folds of the first
rib a in close contact, the pressure being resisted by the mandrel L which is carried
by the movable bed J. The man irel is heli at one end only as at M and surroun ling
the lower portions are a couple of hollow jaws N, N, hinge jointed at P, P. Below
the jaws N, N, are a pair of struts Q, Q, which pass through and project down-
wardly from the sliding bed J, these are connected by a crosshead R and attached
to hand or foot lever rod S, said struts being circled by springs T, T, for
return action.
When the jaws N, N, are open as at Figure 3, the first wished (sheets) of
mica 1, 2, 3, 4, are curved by hand and pushed end on under the mandrel L, the
free edge of the mica appeating as at Figure 3. On the rol Seing released the
springs T, T, close the jaws N, N, and by their contact with the mic make it of
tuhlar form with overlappings eiges.
Each jaw has a stop piece or pieces U, U, one fixed and the other yielding, as a
Figure 2, so that it can yield slightly for the overlapping in the proper manner.
The second rib c is now slipped on the overlaps to enclose them which becomes
pressed into close contact when the sliding bed is returned and the press scren
operated, the tube then appearing as at Figure 6 is withdrawn from between the
jaws N, N, and a fillet rim is slipped over the end of the tube and then placed in
the hollow stock V and a pinch band W Figure 7 closed upon the outer rim, a hand
wheel X being turned carries the tube fillet rim and stock round by the gear wheel Y
and then a roller Z which projects slightly into the tube is brought down by th
lever handle a¹ to give the required grip of the fillet rim on the mica and on the

page_text: eads of the side ribs, a slight ring indent being made in the fillet rim to prevent it
leaving the mica accidentally.
The other end of the mica tube is now similarly treated to make the chimney
complete
With inferior qualities of mica, a further security of pinning the ribs and rims
to the mica is necessary, for which purpose I make eccentric or other shaped
recesses d in the periphery of the mandrel where the pinning is required, and after
driving the pins e through with the heads home, as at Figure 8, I rotate the
mandrel L to bend the points, as at Figure 9, I then again put the tube under the
press head or "force," and make all flat and smooth.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. For the manufacture of mica tubes (chimneys), the construction and arrange-
ment of press with sliding bed in which are hollow jaws and an open ended mandrel
for operation in the manner and for the purposes set forth and substantially as
represented in the annexed drawings.
2. The means or appliances connected with hollow jaws of a sliding bed when
employed for the purposes described and arranged in the manner represented in the
annexed drawings.
3. The means or appliances for compressing and rolling the end fillets or rims on
to mica tubes (chimneys), as set forth and shown.
4. For the clenching pins of mica tubes (chimneys) the recessed mandrel with
rotating action, as described.
The 15th day of October 1895.
H. GARDNER,
Patent Agent, 166 Fleet Street, London,
Agent for the said Eustace Sloper.