IMPROVEMENTS IN FUSIBLE Dra
Year: 1883

page_text: LETTERS PATENT to John William Kenyon of the City of Manchester in the
County of Lancaster Engineer for an Invention of IMPROVEMENTS IN FUSIBLE
Dras
PROVISIONAL SPECIFICATION left by the said John William Kenyon at
the Office of the Commissioners of Patents on the 23rd August 1883.
JOHN WILLIAM KENYON of the City of Manchester in the County of Lancaster,
Engineer, "IMPROVEMENTS IN FUSIBLE PLUGS"
My invention relates to the appliances known, as Smith's fusible plugs and
consists of a method of construction whereby the part containing the fusible alloy
can be readily replaced or exchanged. The said alloy is contained in a conical
piece which is screwed into position in the outer shell of the plug a narrow
shoulder fitting a seating on the inside of the said shell so as to make a tight joint.
The alloy is contained in a space between a hollow conical piece and an inuer cone
the base of the latter touching or almost touching the interior of the hollow cone.
The conical piece is passed upwards into the said outer shell and screwed into
position by means of a suitable key.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John William Kenyon in the Patent Office on the 23rd February
1884.
JOHN WILLIAM KENYON of the City of Manchester in the County of Lancaster,
Engineer, "IMPROVEMENTS IN FUSIBLE PLUGS
"
My Invention relates to the appliances known as Smith's fusible plugs and
consists of a method of construction whereby the part containing the fusible alloy
can be readily replaced or exchanged. The said alloy is contained in a conical
piece which is screwed into position in the outer shell of the plug, a narrow
Bhoulder fitting a seating on the inside of the said shell so as to make a tight
joint. The alloy is contained in a space between a hollow conical piece and an
inner cone the base of the latter touching or almost touching the interior of the
hollow cone. The conical piece is passed upwards into the said outer shell and
screwed into position, by means of a suitable key;
In order that my invention may be fully understood I have attached hereunto
a sheet of drawings to which I will refer in this place. In the said drawings
Fig. 1 represents an outside view of the apparatus, and Fig: 2 a vertical section
of the same.
In the said Figs; a is a hollow nipple of shell which is formed with
a screw thread at a' in order that it can be screwed into a hole drilled or formed
in the furnace crown. The upper part of the bore of the nipple is contracted in
dinmeter and is tapped or formed with a screw thread b. The cone é containing
the fusible metal is formed with a screw thread to fit the thread in the nipple and
is suitably formed to be turned by means of a key. The lower end of the cone
is formed with a narrow shoulder al d and the inner margin of the screwed
opening in the nipple is turned true so that when the cone is screwed tight liome
a water tight joint is obtained. To render the joint more secure I may form
a sinall groove to receive packing as indicated at e. The cone is made höllow and
within it is placed a second cone or thimble f which is also hollow but is closed at
the upper and smaller end: A small annular space is left between the two cones
and this space is filled with fusible metal as is usual in this class of safety
appliances In Fig: 2, the fusible metal is indicated by dots: When the sihaller
coffe has been blown out of the cone o through the melting of the fusible metal
the cone o is unscrewed and removed and a fresh spare cone already provided with
an inner cone and fusible metal can be passed upward through the interior of the
nipple a and be screwed into position by means of a key. The construction as
described and illustrated enables me to obtain a greater accuracy in the screw thread
as a tap of a standard size can be passed completely through the hole in the
nipple a, and the cone c being also chased to a standard size a proper fit of the
said cone is ensured when it is necessary to renew the saine. An important
advantage is that the base of the inner cone fis well shielded from the direct action
of the fire.
Having now fully set forth and indicated the nature of my said invention and
the manner in which I carry the same into practical effect I would have it to be
understood that I claim :-
First. The "fusible plug" or low water safety apparatus of the construction
described and indicated herein before and in and by the accompanying drawings.
And secondly. The nipple a tapped or formed with an inner screw thread at its
upper end and the hollow cone c formed to be passed upwards through the nipple

page_text: and to be screwed tight into its upper end and provided with the inner conë ƒ
secured in place with fusible metal substantially as and for the purpose set forth
and indicated:
In witness whereof Ì the said John William Kenyon have hereunto set my
hand and seal this twenty-second day of February in the year of our Lord one
thousand eight hundred and eighty-four
Signed, sealed, and;
delivered, in the
presence of
}
EDWARD K: DUTTON
41 John Dalton St, Manchester.
(Agent for the Patentée)
JW KENYON (L.S.)