Improvements in Vulcanizers.
Year: 1890

page_text: Date of Application, 8th Dec., 1890-Accepted, 24th Jan., 1891
COMPLETE SPECIFICATION.
Improvements in Vulcanizers.
JOHN HUTCHENS GARTRELL 47 Chapel Street Penzance, Dentist, FRANCIS
KNOEFERL 100 Bolsover Street 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:-
Our invention relates to improvements in dental vulcanizers, in which a copper or
other vessel is closed by a steam-tight lid. On applying heat to the exterior of the
vessel, steam is raised to a pressure and heat sufficient to vulcanize articles of rubber
or other material contained therein; and the objects of our improvements are; first,
to provide a vessel that, notwithstanding it shall be light in weight, will be stronger
and less liable to burst and be independent of flaws such as appear in a casting or
in brazed or jointed materials: second, to provide a lid that shall not be liable to
damage at the steam joint, as is usually the case, when it is removed, and being hot,
is thrown down amongst tools and grit, and, in addition, to be more convenient and
easy to replace when again using the vulcanizer, also simplicity of construction.
We attain these objects by the machinery illustrated in the accompanying drawing;
in which,
Figure 1. is a vertical section of vulcanizer opon, showing one form of hinged lid-
and the means for tightening it to the vulcanizer.
Figure 2. a top view of the same as it appears when the lid is secured to the
vulcanizer.
Figure 3. is an outside elevation at right angles to Fig. 1..
Figure 4. is a vertical section of vulcanizer, showing a second method for tightening
down the lid.
Figure 5. a top view of the same.
Figure 6. a side elevation at right angles to Fig. 4 showing the hinge on the lid.
Similar letters refer to similar parts throughout the several views.
The body (a) of the vulcanizer is constructed of hammered or rolled copper in
one piece throughout, without either brazing or seam. We prefer to make it
cylindrical as shown. The bottom is somewhat stouter than the sides to give pro-
portionate strength, and the top is thickened to form a shoulder (b) partly to
strengthen it at that part and to make a wider face for the packing in forming the
steam-tight joint, but principally to take the strain of the clamping levers (o) or
screw (), dispensing with the rivets usually employed for this purpose. Under this
shoulder and surrounding the top of the vulcanizer, is a ring (d) of gun metal,
wrought iron or other suitable material, upon which are lugs (e) to carry the hinged
lid (). The shoulder on the underside of the ring (d) forms the support when the
vulcanizer is placed in its casing.
This casing is not shown in the drawing.
The lid is made of gun metal or other suitable material, preferably of the
dome shape shown. It is hinged to the ring (d) by the lug (g) and is recessed at (h)
to receive a packing of asbestos, rubber or other material to form a steam-tight
joint, when tightly clamped down. The clamping screw (i) passes through the
bow () and bears on the top of the lid at (k), as better seen in the elevation Fig. 3.
(1) are pins or screws fixed to the ring (d) to form a resistance against the pressure
of the screw (1).
A second method of securing the lid to the vulcanizer is shown in (Fig. 4). The
vulcanizer and shoulder (b) are similar as in (Fig. 1), but the ring (d) carries
lugs (m) diametrically on opposite sides, in addition to the lugs (e) for the lid to
hinge on. The lugs (m) carry two levers (o) having projecting parts (p) bearing on
the lid at a part just opposite the steam joint. The continuation ends pass under

page_text: a recessed screw collar (7) and the latter is screwed on to the part (s). This recessed
collar (r) has drilled into it, one or more holes (t) for the purpose of inserting a
handle (u) in order to turn the collar when tightening down the lid to the
vulcanizer.
The separate hinge may be dispensed with and the lid loosely fastened by a
screw (1) or an equivalent, to one of the clamping levers and so dispensing with a
separate hinge.
We are aware that vulcanizers have been made by forming a cylinder of plate
copper and brazing in the bottom and also the side seams, and also that they have
already been made from a solid casting.
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
1st. In a vulcanizer, the attachment of the lid to the body or its parts by means of
a hinge substantially as shown and described.
2nd. In a vulcanizer constructed as described from a solid copper plate with a
strengthening rim on the top, with the cover attached by a hinge direct to the
vessel or its parts, in order not to necessitate the detaching of the lid when opening
the vulcanizer.
3rd. In a vulcanizer constructed as described, in which the closing of the lid is
effected by means of two clamping levers, the lid hinged or attached to one of the
clamping levers as shown and described.
Dated this 6th day of December 1800
SAML. HANNAH,
51, Lincoln's Inn Fields, London, Patent Agent.