Improvements in the Method of and Means for Protecting Electric Lamp Fittings from Damp and Corrosion, and for Preventing Short Circuiting.
Year: 1896

page_text: Date of Application, 10th July, 1896
Complete Specification Left, 8th Apr., 1897-Accepted, 8th May, 1897
Complete Specification Left, 8th Apr., 1897-Accepted, 8th May, 1897
PROVISIONAL SPECIFICATION.
Improvements in the Method of and Means for Protecting Electric
Lamp Fittings from Damp and Corrosion, and for Preventing
Short Circuiting.
1 JOSEPH LOMAX KENDAL of 2 St. James Square, Manchester, in the County
of Lancaster, Electrical Engineer, do hereby declare the nature of this inventi. i
to be as follows:-
My said invention relates to improved means for protecting the holders an
fittings of electric lamps in bleach works, chemical works, weaving sheds and i
other situations where the presence of acid fumes, gases, steam, water or damıp
gives rise to corrosion in the metallic portions of electric lamp fittings or to "short
circuiting" in such lamps.
According to my invention I box in and protect the whole of the metallic lam
holder, lamp fittings and lamp, by a packed and air-tight casing which effectually
excludes all deleterious gases. fumes and liquids without diminishing the efficiency
of the lamp. The said protecting casing consists of an upper hollow cap or hou'l
of rubber, having a lower flange and fitting over the upper portion of the lamp.
The lower portion of the casing consists of a glass shade or well large enough to
contain the lamp. The flange of the upper rubber cap rests upon the upper rim or
edge of the glass well. The rubber cap and the glass well are held together by a
pair of screwed and recessed jamb washer rings, made preferably of porcelain or
earthenware. A packing ring of rubber is placed between the under side of the
glass well rim or flange and the recess of the jamb washer, the flange of the cap
above and the rubber ring beneath this ensuring a packed air tight joint, so that
nothing of a deleterious nature has access to the casing. The upper rubber cap or
hood is perforated at the crown to allow the connecting wires to pass tightly
through to the points of contact. Thus the surrounding and enclosing casing is
sealed at all points against the entrance of fumes, gases, steam or damp, and the
metallic lamp holder, lamp cap and wire connections are absolutely protected. The
improved lamp might be used for subaqueous lighting purposes. I utilise or may
utilise the aforesaid jamb nut washer rings which hold the two halves of the casing
together, as a means of support for a special papier maché or other shade, the top
flange of the shade entering an annular groove between the two washer rings.
I prefer that the rubber from which the aforesaid upper cap or hood is made and
also the rubber packing ring shall have as little sulphur in its composition as possible
so as to render the said parts more capable of withstanding the effects of acid
fumes and gases.
By means of my invention I obtain complete isolation of the metallic parts
and fittings of an electric lamp so that it lasts much longer and is not liable to get
out of order when used in situations where it is subject to the decomposing effects
of acid fumes, gases, vapours or liquids.

page_text: COMPLETE SPECIFICATION.
Improvements in the Method of and Means for Protecting Electric
Lamp Fittings from Damp and Corrosion, and for Preventing
Short Circuiting.
I JOSEPH LOMAX KENDAL of 2 St. James Square, Manchester, in the County
of. Lancaster, Electrical Engineer, 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 and accompanying drawings:--
My said invention relates to improved means for protecting the holders and
fittings of electric lamps in bleach works, chemical works, weaving sheds and in
other situations where the presence of acid fumes, gases, steam, water or damp
gives rise to corrosion in the metallic portions of electric lamp fittings or to "short
circuiting" in such lamps.
According to my invention I box in and protect the whole of the metallic lamp
holder, lamp fittings and lamp, by a packed and air-tight casing which effectually
excludes all deleterious gases, fumes and liquids without diminishing the efficiency
of the lamp.
The nature of the invention and the manner in which I carry the same into
practical effect will be better understood by referring to the annexed sheet of
illustrative drawings to which I will now refer.
Fig. 1 is an external view of my improved protecting casing, the shade f being
indicated in dotted lines so as not to obscure the other parts.
Fig. 2 is a section on the vertical plane of the protecting casing and parts.
The said protecting casing consists of an upper hollow cap or hood a of rubber,
having a lower flange a¹ and fitting over the upper portion of the lamp B. The
lower portion of the casing consists of a glass shade or well c large enough to
.contain the lamp B. The flange a¹ of the upper rubber cap a rests upon the upper
rim or. edge el of the glass well c. The rubber cap a and the glass well care
held together by a pair of screwed and recesses jamb washer rings d d¹ made
preferably of porcelain or earthenware.
A packing ring e of rubber is placed between the under side of the glass well
rim or flange e¹ and the bottom of the recess of the jamb washer d' the flange a
of the cap a above and the rubber ring e beneath thus ensuring a packed air tight
joint, so that nothing of a deleterious nature has access to the interior of the
casing. The upper rubber cap or hood a is perforated at the crown to allow the
.connecting wires bb which are preferably lead covered, to pass tightly through to
the points of contact.
Thus the surrounding and enclosing casing constituted by the foregoing parts is
sealed at all points against the entrance of fumes, gases, steam or damp, and the
metallic holder, cap and wire connections of the lamp are absolutely protected.
The improved protected lamp might be used for subaqueous lighting purposes as
the described casing will exclude water. I utilise or may utilise the aforesaid
jamb nut washer rings d d which hold the two halves of the casing together, as a
means of support for a special papier maché or other shade f the top flange of the
shade entering an annular groove between the two washer rings as plainly shown
in the drawings. I prefer that the rubber from which the aforesaid upper cap or
hood a is made and also the rubber packing ring e shall have as little sulphur in
its composition as possible so as to render the said parts more capable of with-
standing the effects of acid fumes and gases.
By means of my invention I obtain complete isolation of the metallic parts and
fittings of an electric lamp so that it lasts much longer and is not liable to get out
of order when used in situations where it is subject to the decomposing effects of
acid fumes, gases, vapours or liquids.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is.
The improved protecting casing for electric lamps substantially as hereinbefore
Dated this 7th day of April 1897.
For the Applicant,
E. K. DUTTON & Co.,
5 John Dalton Street, Manchester, Chartered Patent Agents.