Improvements in Heated Calenders for Photographic Purposes.
Year: 1889

page_text: Date of Application, 27th May, 1889-Accepted, 29th June, 1889
COMPLETE SPECIFICATION.
Improvements in Heated Calenders for Photographic Purposes.
I, AUGUST LEUTNER, of No. 12 Mariahilferstrasse, Vienna, in the Empire of
Austria, Gentleman, do hereby declare the nature of my said 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 improvements in heated calenders for photographic
purposes, characterised, firstly, by the automatic adjustability of the calender rolls
for the slight differences in thickness of the cardboard for rendering the adjustment
by hand unnecessary, secondly, the warming of the calender rolls, which requires
very little time and causes a considerable saving of time and fuel.
It is well known that when the regulating device of the ordinary calenders have
been adjusted for a certain thickness of cardboard or the like, the effect will not be
uniform as the said cardboards are very variable in thickness. Even if these
differences are small the want. of uniformity in polish of the boards is severely felt
and can only be prevented by continuously adjusting the regulating device. This
disadvantage is overcome by employing my improved calender, as the small
differences between the kinds or numbers of the thicknesses are automatically adjusted
by the regulating device, for the reason that the rollers possess, not only the
requisite pressure, but also the correct degree of elasticity for producing a uniform
polishing of the various thicknesses of the boards.
In the accompanying drawings, Figure 1 is the elevation, partly in section, of my
improved machine."
Figure 2 is the end view of the same from the crank side.
The two bearing standards a are connected by the rods b so as to form a firm
framework, in which the two calender rollers c, c are arranged one above the other.
The upper roller c¹ is solid or massive, one of its journals, which protrudes from the
bearings, being provided with a crank d, and the other journal with a cog wheel e,
which gears into a second cog wheel e¹ of the roller c, so that when the crank d is
set in operation the two cylinders are set in uniform rotation but in opposite direction
to each other.
For regulating the pressure of the rollers c, c¹, to each other the regulating device
is so arranged that the two bearings of the lower roller c and the roller c itself will
be adjusted in the vertical plane.
The two movable bearings are supported by the volute springs g, which can be
pressed against the bearings by means of the screw spindles i, which run through
the cross connection h of the frame, so that the pressure in the roller bearings can be
regulated at will. In order that the operation of the regulating device may cause the
lower cylinder to lay snugly and uniformly in its entire length against the upper
roller c or against the cardboard, the aforementioned screw spindles i are provided
with rope or chain drums k, which are so coupled by an endless chain, rope, strap, etc.,
that when the one spindle is rotated, the second spindle will be compelled to make a
like movement and in the same direction.
The cylinder or roller c and also the journals of the same are hollow, and in order
to be able to heat the said roller c, I employ, at the one end m of the said hollow
space, a lamp of suitable construction and at the other end a sheet metal tube n as
chimney, which, if made in the proper dimensions, will also serve to produce draught
and draw the flame of the lamp into the roller.
As the heating device does not stand beneath the hollow polished roller, but the
atter, on the contrary is left perfectly free, the same can be readily cleaned, which is
absolutely necessary when heat is employed in calendering.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, what I claim is :-
In heated calenders for photographic purposes:
1-The arrangement of two superposed calender rolls or rollers, the upper of
which is massive and a fixture, whilst the lower roller and the journals to the same
are hollow and are heated by a suitable lamp arranged at one end of the hollow
roller, a sheet metal tube or chimney being applied to the other hollow journal of the
hollow roller, so as to produce the necessary draught for drawing the flame of the
lamp into the cylinder, substantially as and for the purposes set forth in the foregoing
specification, and shown in the accompanying drawings.
2: The combination of the pair of rolls or rollers mentioned in claim 1 with the
device for adjusting the lower heated cylinder in its bearings in the vertical plane,
substantially as and for the purpose set forth in the foregoing specification, and
illustrated on the accompanying drawings.
3: The arrangement of a regulating device, characterised by the lower hollow
roller, its hollow journals being adjustable in the vertical plane by means of two
screw spindles and two volute springs, arranged between the movable bearings and
the spindles so that the same can be pressed with more or less elastic force onto
the massive stationary cylinder, substantially as and for the purpose set forth and
shown.
4: The construction and arrangement of the screw spindles of the regulating
device with rope or chain drums and an endless chain, rope or strap in order to.
produce a perfectly uniform revolution of the said spindles, a perfectly uniform
tension in the volute springs and a perfectly uniform pressing of the lower movable
roller onto the stationary roller, substantially as and for the purposes set forth and
shown.
Dated this 97th dow of Mo.. 1000
W. P. THOMPSON & BOULT,
Agents.