IMPROVEMENTS IN FANS FOR VENTILATING MINES AND FOR OTHER PURPOSES
Year: 1879

page_text: LETTERS PATENT to Thomas James Bowlker, of Heddon-on-the-Wall, in the
County of Northumberland, Mining Engineer, and Matthew Watson, of
Maryport, in the County of Cumberland, Mining Engineer, for the Invention
of "IMPROVEMENTS IN FANS FOR VENTILATING MINES AND FOR OTHER
PURPOSES."
Sealed the 18th June 1880, and dated the 20th December 1879.
PROVISIONAL SPECIFICATION left by the said Thomas James Bowlker and
Matthew Watson at the Office of the Commissioners of Patents on the 20th
December 1879.
THOMAS JAMES BOWLKER, of Heddon-on-the-Wall, in the County of Northum-
berland, Mining Engineer, and MATTHEW WATSON, of Maryport, in the County of
Cumberland, Mining Engineer. IMPROVEMENTS IN FANS FOR VENTILATING MINES
AND FOR OTHER PURPOSES."
This Invention relates to improvements in fans for ventilating mines and for
other purposes.
In carrying out our improvements we construct the fan with two or more
outlets or chimneys through which the fan may discharge its air, such outlets or
chimneys being preferably rectangular in cross section, and having the sides thereof
which are parallel with the axis so shaped as to gradually increase the sectional
area of the outlets from the point where they leave the fan circumference to the
point where they discharge into the open air, and as each opening commences at
the termination of the one before it the whole circumference is made available for
the free discharge of the air.
The vanes or blades of the fan we make almost tangential at their commencement,
curving them forwards in direction of rotation until they become radial or nearly
radial at their outer ends.
Further, we construct the outer side of the outlets or chimneys which are parallel
with the axis, so that they may be moved hingewise in order to allow of varying
the area available for discharge.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas James Bowlker and Matthew Watson in the Great Seal Patent
Office on the 19th June 1880.
THOMAS JAMES BOWLKER, of Heddon-on-the-Wall, in the County of Northum-
berland, Mining Engineer, and MATTHEW WATSON, of Maryport, in the County of
Cumberland, Mining Engineer. "IMPROVEMENTS IN FANS FOR VENTILATING MINES
AND FOR OTHER PURPOSES."
This Invention relates to improvements in fans for ventilating mines and for
other purposes.
In carrying out our improvements we construct the fan with two or more outlets
or chimneys through which the fan may discharge its air, such outlets or chimneys
being preferably rectangular in cross section, and having the sides thereof so shaped
as to gradually increase the sectional area of the outlets from the point where they
leave the fan circumference to the point where they discharge into the open air,
and as each opening commences at the termination of the one before it, the whole
circumference is made available for the free discharge of the air.
The vanes or blades of the fan we make almost tangential at their commencement,
curving them forwards in direction of rotation of the fan until they become radial
or nearly radial at their outer ends.
The curve of the vanes will differ somewhat in different fans, depending upon the
quantity of air required to be circulated and on the water gauge or vacuum
required to circulate this air.
In cases where the circumstances of ventilation are apt to vary it is desirable to
make provision for the different quantities of air required to be passed through the
fan at different times. This is effected in the guibal fans by means of a shutter
sliding close to the periphery of the vanes, but this alters the sectional area of the
outlet at one point only. According to our Invention the outer side (i.e., the side
furthest from the centre of the fan) of the discharge outlets is made to move on a
hinge at its inner end, by which means the sectional area of the outlet can be
altered throughout its entire length, and its area be thereby accommodated com-
pletely to the varying quantities of air that may be passed through it.
The casing of the fan will generally be best made of wrought iron, though when
of a small size cast iron will become a more suitable material.
But to make our Invention better understood we will proceed to describe the
same by reference to the accompanying Drawing, in which Figure 1 is a sectional
elevation of a fan suitable for ventilating a mine constructed according to our
Invention; Figure 2 is an end view of the fan, and Figure 3 is a plan half in
horizontal section of the same. Similar letters in all the Figures represent similar
parts.
a, a, shew the fan casing; b, b, b, the outlets or chimneys; it will be seen that
these outlets are rectangular in cross section, the sides c, c, c, c, thereof being so
shaped as to increase the sectional area of the outlets from the point d to their outer
ends where they discharge into the open air; e, e, e, e, shew the peculiar shape of
the vanos or blades of the fan; f, f, f, are the hinges of the outer sides of the
discharge outlets b, b, to allow of altering the sectional area of the same; the other
parts of the fan being of the ordinary construction need no further description.
Having thus described the nature of our said Invention, and the best means with
which we are acquainted for carrying the same into effect, we wish it to be under-
stood that we do not confine ourselves to the precise details herein laid down and
shewn in the Drawing, as the same may be varied without departing from the
poculiar character of our Invention; but what we do claim is,-
Firstly. The general arrangement and construction of a rotary fan, having two

page_text: or more discharge outlets or chimneys and a number of vanes or blades, constructed
substantially in the manner and for the purposes herein before described and
represented in the accompanying Drawing or any mere modification thereof.
Secondly. Hinging the outer sides of the discharge outlets of fans so as to allow
of regulating the area available for the discharge of air, as herein-before described.
In witness whereof, I, the said Thomas James Bowlker, for and on behalf of
myself and the said Matthew Watson, have hereto set my hand and seal,
this Sixteenth day of June, in the year of our Lord One thousand eight
hundred and eighty.
THOMAS JAMES BOWLKER. (LS.)