Improvements in Means for Controlling the Air about Moving Belts and Machinery.
Year: 1890

page_text: ate of Application, 21st Oct., 1890-Accepted, 22nd Nov., 1890
COMPLETE SPECIFICATION.
Improvements in Means for Controlling the Air about Moving Belts
and Machinery.
I, ARCHIBALD JAMES ROBERTSON of 1007 Opera House Block, Chicago, Illinois,
United States of America, Mechanical 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 means for controlling the air about moving belts and
machinery. It is illustrated in the drawings wherein;
Figure 1 is a vertical section and
Figure 2 a cross section of a portion of the device.
A is the framework upon which the parts are supported, B a shaft suitably journaled
on such frame carrying the pulley D. F is a second shaft similarly journaled carrying
the large pulley G and a small pulley (not seen) to drive the fan. The casing is made
of two compartments K and L of substantially equal size supplied respectively with
the air supply valves M and O and the discharge pipes N and P. R is a diaphragm
between the two compartiments, slotted to permit the rotation of the pulleys G and D,
over which travels the belt S. T is the belt which drives the fan U, and V and
W are pipes leading from the discharge pipes N and P to such fan. X is a door in
the side and Y Y are the bolts securing the pipes together. The central portion of
the diaphragm may be loose and removable and inserted in place to rest upon the
ledge R¹ after the lower portion of the case has been set in position and the belt
put on.
The fan U may be driven from any desired source and the shaft F may be in like
manner driven from any desired source so as to impart an excessively high speed to
the shaft B. It is the fact that in such an arrangement a certain amount of
retardation or injurious friction results from the pressure of the air upon the belt and
its contact with the moving parts, and in certain classes of machinery this evil result
it is desired to obviate. If now the fan be started in operation it will draw currents
of air from the valves M and O through the compartments in the direction of rotation
of the belt and in the direction indicated by the arrow, thus placing the moving belt
in a current of air moving perhaps with the same velocity as the belt and in the same
direction therewith. Such current of air is of course created only as the flat valves
are open and in proportion to the degree to which they are opened. The flat valves
are, of course, elastic and the degree of their elasticity may be such as to keep them
normally closed except when the chambers have been greatly exhausted of air so that,
for example, they would not open until the chambers had been exhausted of air so as
to make the pressure within them one-half or perhaps one-fourth of that without.
Under these circumstances the air is simply exhausted from the chambers and there
would be little or no current of air therethrough.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is;
1. The use of a two part case which contains the moving portions of a belt, with
means for passing currents of air through such compartments in the direction of the
moving belt.
2. Relieving the friction and pressure of the atmosphere upon the moving parts
and belts of machinery by enclosing the same in chambers and passing currents of air
through such chambers in the direction of motion of the moving parts.
3. The chambers K and L with the diaphragm R between them and exhausting
pipes connected one with each of their opposite extremities.

page_text: 4. Relieving the friction and pressure of the atmosphere upon the moving parts and
belts and mechanism of machinery by enclosing the same in chambers and exhausting
air from such chambers in the direction of motion of the moving parts.
Dated this 21st day of October 1890.
FREDERIC PRINCE,
1, Quality Court, Chancery Lane, London, Agent for Applicant.