Improvements in Air Propellors or Fans.
Year: 1893

page_text: Date of Application, 6th Jan., 1893
Complete Specification Left. 6th Nov.. 1893-Accepted, 9th Dec.. 1893
PROVISIONAL SPECIFICATION.
Improvements in Air Propellors or Fans.
I, WILLIAM TATTERSALL, of 90, Arden Terrace, Accrington, in the County
of Lancaster, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to air propellors or fans of the screw or radial blade type
and its object is to prevent or modify the tendency to produce a centrifugal current
and to keep it more parallel to the axis of the fan.
For this purpose I incline the blades to the axis of the fan at a suitable angle
and I make them of a curved or concavo-convex cross section. The curve of the
blades may be uniform from end to end or they may be in the form of a portion of
a cone.
By this construction the air is in a great measure prevented from being driven
in a radial direction but is propelled approximately parallel to the axis of
the fan.
Dated this 5th day of January 1802
DRACUP & NOWELL,
Bradford, Agents.
COMPLETE SPECIFICATION.
Improvements in Air Propellors or Fans.
I, WILLIAM TATTERSALL, of 90, Arden Terrace, Accrington, in the County
of Lancaster, 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 improvements in air propellors or fans of the screw or
radial blade type and its object is to prevent or modify the tendency to produce a
centrifugal current and to keep it more parallel to the axis of the fan.
For this purpose I incline the blades to the axis of the fan at a suitable angle
and I make them of a curved or concavo-convex cross section. The curve of the
blades may be uniform from end to end or they may be in the form of a portion of
a cone.
By this construction the air is in a great measure prevented from being driven
in a radial direction but it is propelled approximately parallel to the axis of
the fan.
Reference is to be had to the accompanying sheet of drawings forming a part of
this Specification in which similar letters of reference indicate corresponding parts
in each of the figures.
Figure 1, represents an elevation of the feed side of my improved fan or air
propellor in which the fan shaft is shown in section and the radial arms for
supporting the central bearings for the shaft are represented broken away to show
the fan more clearly.
Figure 2, is a side view of the same with only one of said radial arms broken
away. The arrow in each of the figures indicates the direction of rotation.
The annular frame A is provided with radial arms B to support the bearings C
for the fan shaft D all of which may be of ordinary construction. The central
boss E of the fan is made with its front end F in the form of an obtuse cone and in
or on this conical end inclined faces are formed at a suitable angle to receive and
give the required inclination to the arms G which are secured thereto by the
Price Q71

page_text: bolts H. The fan blades J are attached to the arms G by the rivets K. A driving
pulley L is mounted in the usual way upon the fan shaft.
It is obvious that two or more blades may be used instead of four and that the
form of the blades may be modified.
r
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 :
A fan or air propellor of the screw bladed type having its blades inclined bodily
backwards from the fan shaft, or point of attachment thereto, towards the delivery
side of the fan, for the purpose of checking the centrifugal tendency or to impel the
current approximately parallel to the axis of the fau, substantially as herein shown
and described and illustrated in the accompanying drawings.
Dated this 3rd day of November 1893.
DRACUP & NOWELL,
Bradford, Agents.