IMPROVEMENTS IN OR CON- NECTED WITH THE STEAM GENERATING APPARATUS OF SHIPS OR VESSELS
Year: 1878

page_text: LETTERS PATENT in John Isaac Thornycroft, of the Firm of John I. Thorny-
croft and Co. of Church, Wharf, Chiswick, in the County of Middlesex, Steam
Yacht and Launch Builders. for the Invention of IMPROVEMENTS IN OR CON-
NECTED WITH THE STEAM GENERATING APPARATUS OF SHIPS OR VESSELS."
Sealed the 15th April 1879, in pursuance of an Order of the Lord Chancellor, and
dated the 3rd September 1878.
PROVISIONAL SPECIFICATION left by the said John Isaac Thornycroft at
the Office of the Commissioners of Patents on the 3rd September 1878.
Joux ISAAC THORNYCROFT, of the Firm of John 1. Thornycroft and Co., of
Church Wharf. Chiswick, in the County of Middlesex, Steam Yacht and Launch
Builders. IMPROVEMENTS IN OR CONNECTED WITIL THE STEAM GENERATING
APPARATUS OF SHIPS OR VESSELS."
My Invention has for object to lessen the risk of injury to persons in the stoke-
holes of ships or vessels in the event of steam escaping into the boiler furnaces
owing to the bursting of boiler tubes or other leakage. For this purpose I arrange
passages or conduits in communication with the ash pits or pans and with the open
air, which passages or conduits I provide with suitable doors or closures, to be kept
normally closed, but capable of being readily opened to allow of the escape of
steam or heated gases in the event of any sudden and undue increase of pressure
within the furnace flues, ash-pit, or jan, arising from leakage out of the boiler, as
above mentioned. In conjunction with the passages or conduits above described it
is usually advantageous to so arrange the furnace and ash-pit doors that they may
automatically close in the event of any undue pressure arising within the furnace
flues and ash-pit.

page_text: on the
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said folin Isaac Thornycroft in the Great Seal Patent Office
16th April 1879.
JOHN ISAAC THORNYCROFT, of the Firm of John I. Thornycroft and Co., of
Church Wharf, Chiswick, in the County of Middlesex. Steam Yacht and Launch
Builders. IMPROVEMENTS IN OR CONNECTED WITH THE STEAM GENERATING
APPARATUS OF SHIPS OR VESSELS."
My Invention has for object to lessen the risk of injury to persons in the stoke-
holes of ships or vessels in the event of steam escaping into the boiler furnaces
owing to the bursting of boiler tubes or other leakage. For this purpose 1. arrange
passages or conduits in communication with the ash pits or pans and with the open
air, which passages or conduits I provide with suitable doors or closures, to be kept
normally closed, but capable of being readily opened to allow of the escape of steam
or heated gases in the event of any sudden and undue increase of pressure within
the furnace flues, ash-pit, or pan arising from leakage out of the boiler, as above
mentioned. In conjunction with the passages or conduits above described it is
usually advantageous to so arrange the furnace and ash-pit doors that they may
automatically close in the event of any undue pressure arising within the furnace
flues and ash-pit.
Referring to the accompanying Drawings,
Fig. 1 is a longitudinal vertical section of part of a vessel with boiler and blowing
apparatus in elevation.
Fig. 2 is a side elevation partly in section (to a larger scale) shewing a portion of
the boiler and other parts,
Fig. 3 is a plan.
Fig. 4 is a front view shewing the fire-box, ash pan, bunkers, and passage or
conduit for the escape of steam or heated gases as aforesaid.
Fig. 5 is a section to a larger scale of part of the ash pan shewing an arrange-
ment of door or valve designed to close automatically when the pressure in the
stoke-hole is not in excess of that in the ash pan.
Fig. 6 is a view (partly in vertical section) shewing the door or closure of the
passage or conduit for escape of steam or heated gases, and the means for securing
it in the closed position and for opening it when released or unfastened.
Fig. is a plan.
Fig. 8 is an end view of part of the fastening apparatus.
1 is the boiler: 2, the fire-box: 8, the ash pan: 4, the stoke-hole: 5, the appa-
ratus (of any suitable construction) whereby air is forced into the stoke-hole and
thence through the ash pan to the fire as usual. Each of the ash pan doors or
valves G is suspended by links 7 so as to open as indicated by dotted lines in
Figs. 2 and 5.
According to my Invention, in order to lessen the risk of injury to persons in the
stoke-hole in the event of leakage from the boiler into the furnace or ash-pit as
aforesaid. arrange a passage or conduit 8 in communication at 8" with the ash-pit
or pan, and at 8 with the open air.
Normally this passage is kept closed at the upper end by a door 9. This door
is hinged at 10.
Referring to Figs. 6. 7. and 8. 11 is a spring bolt carried in guides in a small
frame 12: 13 is a recessed portion of the door 9 to receive the end of the bolt 11.
so that the door 9 may be kept normally closed, but will be released in the event of
sudden or undue pressure against its under side: 14 is a screw. by turning which
the resistance of the bolt 11 may he adjusted: 15 is a lug or projection carried by
the bolt 16 is a rod connecting this lug or projection with an arm 17 fixed on a
spindle 18, on which is fixed another arm 19, whence a rod or other attachment is
provided to any convenient place, so that the stoker or other person may readily
withdraw the bolt 11, and so unfasten the door 9.

page_text: When released the door 9 is caused to open as shewn dotted in Fig. 6 by the
following arrangement:-20 is a lug or part secured to the door 9, and to which is
connected one end of a rod 21, whose other end is screwed and fitted with a nut 22
and washer 22×. The rod is surrounded by a spring 23 (adjustable by the nut),
which when the door is shut is in compression, and when the door is released causes
it to open, as shown in Fig. 6.
It will be evident the means described for securing the door and for causing it to
open automatically may be modified in detail without departure from the essential
characteristics of my invention.
What I consider to be novel and original, and therefore claim as the Invention
secured to me under the Letters Patent herein-before in part recited is, providing
the steam generating apparatus of ships or vessels with passages or conduits leading
from the ash-pits or pans to the open air, and furnished with doors or closures, sub-
stantially as described, so as to lessen the risk of injury to persons in the stoke-holes
in the event of steam escaping into the boiler furnaces owing to the bursting of
boiler tubes or other leakage; and also I claim the combination and arrangement of
apparatus substantially as shown in and described with reference to the accom-
panying Drawings, and in which a passage or conduit and door or closure
described are used in conjunction with doors so arranged that they may automatically
close and prevent escape or leakage of heated gases or steam into the stoke-hole in
the event of any undue pressure arising within the furnace flues and ash pit.
ag
In witness whereof. I, the said John Isaac Thornycroft, have hereunto set my
hand and seal, this Sixteenth day of April, in the year of our Lord One
thousand eight hundred and seventy-nine.
JOHN I. THORNYCROFT. (L.S.)