Improvements in Fans for Ventilating Mines or Tunnels, or for other analogous purposes.
Year: 1894

page_text: Date of Application, 28th Dec., 1894-Accepted, 2nd Feb., 1895
COMPLETE SPECIFICATION.
Improvements in Fans for Ventilating Mines or Tunnels, or for
other analogous purposes.
1 HUGH WILLIAM WADDLE of Llanmore Works Llanelly in the County of
Carmarthen Engineer do hereby declare the nature of my invention and in what
manner the saine 18 to be performed to be particularly described and ascertained
in and by the following statement:—
The object of my invention is to provide a fau in which a greater suction is
obtained for a given speed than in fans as hitherto constructed with economy of
power and increased efficiency.
According to my invention I provide blades which at the part, or a portion of
the part which is situated between the eye of the fan and the periphery are not
made with the convex side of the curve of the blades in the direction of revolution
of the fan, but are made flat, or radial, or approximately radial, but preferably
scoop-shaped, or concave, in the direction of revolution of the fan; the parts which
are at the inner part, or eye, of the fan, being made scoop-shaped, or, of any other
suitable shape; but preferably radial, or approximately radial, to the eye of the
fan. I prefer to combine with fans provided with blades thus formed a flaring- or
trumpet-shaped discharge at the periphery such for instance as is described in the
Specification of Letters Patent No. 4826 of the 19th March 1889 granted to me or
in the Specification of my application for Letters Patent No. 7476 of the 14th April
1894 as the fans efficiency will thereby be increased relatively to the power
employed.
The accompanying drawing represents in elevation (with part broken away to
shew the interior) a fan made in what I consider the preferable form according to
my invention for suiting the conditions of an average coal mine. A is the eye of
the fan and B is the periphery. C are the checks D are the blades and E are the
intermediate blades. The said blades D at the part from e to f and also the
intermediate blades E are made concave in the direction of revolution of the fan
which direction is indicated by the arrow. The portion of the blades D froing to e
is made approximately radial to the centre of the eye of the fan as shewn.
The part from e tof of the blades D may be made of greater or lesser concavity
than that shewn or it may be flat but many case it is not curved so that its
convexity is in the direction of revolution of the tan aud this applies also to the
blades E.
Although I have shewn the part of the blades D from g to e approximately radial
it may be of any suitable form and direction relatively to the eye of the fan and to
the other portion of the blade.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim 18.
1. A fan for ventilating mines, or tunnels, or for analogous purposes, the said fan
having blades shaped and arranged substantially as hereinbefore described and
illustrated in the accompanying drawings.
2. In fans for ventilating mines, or tunnels or for analogous purposes, blades with

page_text: the portion, or part of the portion, between the eye of the fan and the periphery,
made flat, or scoop-shaped, or concave, on the side in the direction of revolution of
the fan substantially as hereinbefore described.
Dated this 28th day of December 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, Agents.