Improved Means for Heating Rolls employed in Laundries, Paper Mills, and other Places, applicable also to the Heating of other Articles.
Year: 1894

page_text: Date of Application, 30th May, 1894
Complete Specification Left, 28th Feb., 1895-Accepted, 4th May, 1895
PROVISIONAL SPECIFICATION.
Improved Means for Heating Rolls employed in Laundries, Paper
Mills, and other Places, applicable also to the Heating of other
Articles.
We, FRANK CHRISTY, Electrical Engineer, and LEONARD FELL CHRISTY,
Electrical Engineer, both of Broomfield Road Works, Chelmsford, in the County
of Essex, do hereby declare the nature of this invention to be as follows:-
Our invention relates more particularly to improved means for heating the rolls
employed in ironing or glazing machines in laundries the rolls employed in paper
calendering or for other uses though the invention is also applicable to the heating
of other articles than rolls such as plates for baking or cooking or the plates of
burnishing machines or other metallic or non-metallic surfaces or substances.
In applying our invention for example to the roll of an ironing machine we
employ a cylinder tube or block of suitably insulated metal, porcelain or other
suitable material and cover it with a quantity of wire of high electrical resistance.
Such wire may be disposed on the surface in various ways but we prefer to form a
spiral groove around said surface and to lay the wire therein, afterwards covering
same with a layer of some suitable insulating cement; or a vitreous material-or
porcelain slip may be used these materials being fixed by means of heat if they
require it. The cylinder tube or block so prepared is inserted into the hollow roll
and is temporarily centred in same. The cylinder being less in diameter than the
interior diameter of the roll a space is left between the cylinder and the wall of
the roll into which space we run molten zinc or some suitable metal or alloy having
a sufficiently high melting point and possessing sufficient heat conducting power.
This metal layer effectually preserves the wires in the cylinder from oxidation and
also forms to a considerable extent a retainer or equalizer of the heat developed
when a heating current of electricity is passed through the wires such heat being
maintained on the surface of the roll in a very uniform manner.
In this connection we may mention that the preserving of the wires from
oxidizing is necessary to the life of the roll or like, a plaster of Paris roll which
we have tried failing in this respect on account of its porosity.
The connections with the wires may be of any suitable kind but we prefer to
secure the ends of the heating wire to copper brass or like rods carrying wheels or
pulleys revolving with the rod into which the current is passed or from which it
may be taken off by metal chains cords or brushes.
Dated the 30th day of May 1894.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improved Means for Heating Rolls employed in Laundries, Paper
Mills, and other Places, applicable also to the Heating of other
Articles.
I, FRANK CHRISTY, Electrical Engineer, and LEONARD FELL CHRISTY,.
Electrical Engineer, both of Broomfield Road Works, Chelmsford, in the County
of Essex, 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 more particularly to improved means for heating the rolls
employed in ironing or glazing machines in laundries, the rolls employed in paper
calendering or for other uses, though the invention is also applicable to the heating
of other articles than rolls, such as plates for baking or cooking, or the plates of
burnishing machines or other metallic or non-metallic surfaces or substances.
To clearly explain our invention we will describe it in connection with the roll of
an ironing machine such as is illustrated in the accompanying drawings in
which :--
Fig. 1 is a longitudinal section of same, and
Fig. 2 is an end elevation.
As shown in the drawings we place in the interior of the roll a a tube b of
porcelain, terra cotta, earthenware, or the like, though it may be a plate, block, or
cylinder, depending upon the apparatus in which it is employed, and the material
may be metal if suitably insulated, or other suitable material. The tube b has
preferably a shoulder or distance piece cat one end, a space being left otherwise
between the outer surface of the tube and the inner wall of the roll.
The tube has a spiral groove formed on its outer surface in which is laid a wire
or wires d of high electrical resistance (such as an iron wire) which is then covered
and insulated with a layer of some suitable insulating material such as cement or
plaster, or porcelain slip which may be well rubbed in between the interstices of the
wire d and allowed to harden or fixed by heat if necessary. In place of grooving
the tube b the wire may be simply laid thereon and suitably insulated. We have
found iron wire particularly well adapted for the purpose on account of its
considerable increase of resistance as the temperature rises, the effect of which
is to cause it to take less current and thus in a measure automatically regulate the
temperature. The tube thus prepared may be placed on the roll, its centre
having been previously filled with a suitable hard cement e in which are inserted
the ends of brass tubes ff, these having been previously centred in same in some
suitable way.
When the tube so prepared has been properly centred in the roll a we run into
the space between the tube and the inner wall of the roll, molten zinc g or some
suitable material metal or alloy having a sufficiently high melting point, and
possessing sufficient heat conducting power. This metal layer efficiently preserves
the resistance wire from oxidation and also forms to a considerable extent a retainer
or equalizer of the heat developed when a heating current of electricity is passed
through the wires, such heat being maintained on the surface of the roll in a very
uniform manuer In this connection we may mention that the preserving of the
wires from oxidizing is necessary to the life of the roll or like, a plaster of Paris
roll which we have tried failing in this respect on account of its porosity.
A convenient means of making connection with the resistance wire is to pass the
ends of same through holes h h in the tube b and to attach them to copper or like
wires which are secured to the brass tubes ff. These brass tubes may have
their ends flared or jagged as shown in order to give them a hold on the cement

page_text: filling e while on their outer ends where they pass through blocks j j of insulating
material such as vulcanized fibre which close the ends of the roll, are placed short
lengths of copper tubes k k removably held to the blocks jj by nuts 1 l, and
carrying pulleys m m by which the current enters and leaves the roll respectively,
contact making brushes rubbing on the pulleys being used for this purpose, or
contact making chains or cords such as n (Fig. 2) suitably weighted and attached
to a terminal o. By removing the blocks ; the outer tubes k can be withdrawn for
the purpose of renewing the contact pulleys m, or for other purposes.
Our invention when applied to heating other apparatus than rolls will be carried
out on the same lines but with the modifications necessary to adapt it to said
apparatus.
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 electrically heated apparatus the employment with suitably insulated
resistance wires of a superposed layer or filling of a suitable material, metal or
alloy, substantially as and for the purposes described.
2. The combination with a plate, block, cylinder, tube or the like of a resistance
wire or wires wound or laid thereon, a layer of suitable insulating material between
and over said wires, and a superposed layer or filling of a suitable material,
metal or alloy, substantially as described and for the purposes set forth.
3. In combination a plate, block, cylinder, tube or the like, an iron wire or wires
wound or laid thereon, a layer of cement between and over said wires, and a
superposed layer or filling of zinc or a suitable metal or alloy, substantially as
described and for the purposes set forth.
4. The improved construction and arrangement of parts for electrically heating
a roll or the like, substantially as described and illustrated in the accompanying
drawings.
Dand the 20th dow of Wahwanz 100%
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent,
For the Applicants.