Improvements in the Tubes or Cases of Electric Fuses.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in the Tubes or Cases of Electric Fuses.
I, THOMAS TAYLOR, of the Firm of Taylor, Tunnicliff and Company, of East-
wood, Hanley, in the County of Stafford, Manufacturer, do hereby declare the
nature of this invention to be as follows:-
This invention relates to the tubes or cases of electric fuses.
Such tubes or cases have heretofore been made from earthenware or like vit-
reous material, with plain bores, and owing to the circumscribed limits of their
cross sectional area, the same have been liable to split in case the fuse flames or
melts.
According to my improvements, the cross sectional area of the bore of the
fuse tube or case is greatly increased without increasing the external diameter,
and owing to this increase of internal superficial area or air surface surrounding
the fuse, the same is better insulated, and further, assuming that the said fuse
does flame or melt, it is much less likely to split or break the case.
In carrying out one form of safety fuse tube according to my invention, I take
an earthenware tube of any suitable external diameter, and I provide the inside
bore of the same with longitudinal flutings, reedings, ribs, scollops, corrugations
or the like so as to give a zig-zag cross section thereto, and which ribs or beadings
or the like may run either in the direction of the axis of the tube, or spirally.
By such a formation of the inside walls, the superficial area of the inside of the
tube or the cross sectional area of the bore are very materially increased.
Instead of the reedings, scollops, channels or like formations being run in the
longer directions of the tube they may run in the shorter direction or laterally,
thus forming a series of annular reedings, beadings, rises, corrugations or the like
separated from each other by annular depressions, ruts, cavities or the like.
Assuming that a fuse enclosed within my improved tube melts, then the heat
generated by such fusion has not the same opportunity of conveying itself to the
tube as it would have in the case of a plain bore tube, from the fact that the said
heat is conveyed at once only to the points or edges of the corrugations or ribs
and not to the body of the tube.
My invention is also applicable to fuses for switches cut-outs, ceiling roses and
other electrical fittings having a fuse tube or lead pipe for carrying the fuses or
lead wires of the same.
THOMAS TAYLOR,
By Henry Skerrett,
Agent for Applicant.

page_text: Improvements in the Tubes or Cases of Electric ruses.
I, THOMAS TAYLOR, of the Firm of Taylor, Tunnicliff and Company, of East-
wood, Hanley, in the County of Stafford, Manufacturer, 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 the tubes or cases of electric fuses for various purposes.
Such tubes or cases have heretofore been made from earthenware or like vit-
reous material, with plain bores, and owing to the circumscribed limits of their
cross sectional area, the same have been liable to split in case the fuse flames or
nielts.
According to my improvements the internal or cross sectional area of the bore
of the fuse tube or case is greatly increased without increasing or affecting the
external diameter, and owing to this increase of internal superficial area sur-
rounding the fuse, the same is better insulated, and further, assuming that the
said fuse does flame or melt, it is much less likely to split or break the case.
Figure 1 of the accompanying drawing represents partly in longitudinal section
and partly in elevation, a straight fuse case constructed according to one form of
my invention.
Figure 2 is a cross section of Figure 1, upon the dotted line x.
Figure 3 represents, also partly in elevation and partly in longitudinal section,
an elbow fuse tube constructed according to this same form of my improvements.
In carrying out this form of safety fuse tube, I take an earthenware tube a, of
any suitable external diameter, and having a plain exterior surface, and I provide
the inside bore a¹, of the same with longitudinal flutings, reedings, ribs, corruga-
tions or the like a², so as to give a zig-zag cross section thereto (see Figure 2)
and which ribs or beadings or the like may run either in the direction of the axis
of the tube as shown, or they may run spirally along the said bore. By such a
formation of the inside walls, the superficial area of the inside of the tube or the
cross sectional area of the bore are very materially increased.
Figure 4 represents, partly in elevation and partly in longitudinal section, a
modified form of my invention, in which, instead of the reedings, ribs, channels
or like formations being run in the longer directions of the tube, they run in the
shorter direction or laterally or around the internal circumference, thus forming
a series of annular reedings, beadings, rises, corrugations or the like separated
from each other by annular depressions, ruts, cavities or the like.
Figure 5 is a cross section of this modification, upon the dotted line x¹, Figure 4.
Figure 6 represents partly in elevation, with the two ends in longitudinal
section, this form of my invention applied to an elbow fuse tube.
In Figures 4, 5 and 6, a is the fuse tube, with the interior or bore a¹, of the
same provided with a series of annular ribs, reedings or like annular forma-
tions a², separated from each other by intervening channels a³, thus giving a
scolloped or undulatory longitudinal section to the said tube and increasing the
area of the internal surface thereof.
Figure represents another modification of my invention in which the straight
or spiral ribs a³, are of such a shape as to give an undulatory or scolloped cross
section to the tube or casing, whilst in
Figure 8 the said ribs a², are more of a square section, and are separated by
square or trough section channels or ruts, said ruts or channels and ribs or bead-
ing running either straight or spirally throughout the length of the case.
Assuming that a fuse enclosed within the improved tube herebefore described,

page_text: should from any cause, melt or flame, then the heat generated by such fusion has
not the same opportunity of conveying itself to the tube as it would have in the
case of a plain bore tube, from the fact that the said heat is conveyed at once only
to the points or edges (marked at in all the figures) of the corrugations or ribs and
not to the body of the tube.
My invention is applicable to fuses for switches, cut-outs, ceiling roses and other
electrical fittings having a fuse tube or lead pipe for carrying the fuses or lead
wires of the same.
Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what
I claim is:-
First: Increasing the internal superficial area of tubes or cases for electrical
fuses by forming along the bore of the same, longitudinal or helical reedings,
ribs, flutings, corrugations or like formations, substantially as and for the purpose
described and set forth.
Secondly Increasing the internal superficial area of tubes or cases for elec-
trical fuses by forming in or around the bore of the same annular ribs, flutings,
reedings, corrugations or like formations, substantially as and for the purpose
described and set forth.
Dotod thin 25th dow of Tohmann 1900
THOMAS TAYLOR,
By Henry Skerrett,
24, Temple Row, Birmingham, Agent for Applicant.