Improvements in Joints for Manhole Covers for Steam Boilers and the like..
Year: 1897

page_text: Date of Application, 3rd Aug., 1897-Accepted, 30th Oct.,
1897
[Communicated from abroad by THE HOGAN BOILER COMPANY, a Corporation
organized under the laws of the State of West Virginia, U.S.A., and doing
business at Middletown, in the County of Orange and State of New York, U.S.A.]
Improvements in Joints for Manhole Covers for Steam Boilers
and the like..
I, WILLIAM JORDAN, Patent Agent, of 120 Chancery Lane, London, England,
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:-
The object of this invention is to furnish a means of applying a conical metallic
packing ring between a conical seat in a manhole frame and a conical rim upon
the manhole cover.
.
In such a construction it is desirable to make the seat and the manhole circular,
that they may be trued in a turning lathe, and the seat for the conical ring, as
well as the rim of the manhole cover, must be flared inwardly, so it they may be
held tightly to the seat by the pressure generated within the receptacle to which
the cover is applied. The conical rim of the cover at its largest end must neces-
sarily be able to pass through the conical seat upon the frame at its smallest end:
while the larger end of the conical ring being equal in diameter to the larger end
of the seat, could not pass directly through the smaller end of the same.
The invention consists in the combination with such a seat and cover, of a
flexible undivided metallic ring, which may be pressed into an oval shape to force
it through the smaller end of the seat, and adapted to make the joint between the
seat and cover when the latter is drawn inside the ring by a bolt and bridge, or
other suitable means.
In manholes of suitable size it has been found difficult in practice to hold such
a flexible ring in a proper position upon the seat, while the cover is adjusted and
pressed thereon, and I therefore prefer to provide an annular shoulder at the outer
end of the conical seat to which the outer edge of the ring is fitted. Such shoulder
holds the ring true upon the seat when the draft is exerted upon the cover and
prevents the displacement or any slipping of the ring when the cover is forced
home upon the same. The ring may be made of copper, lead, or other compressible
metal, which is adapted to form a steam or water-tight joint botween the smooth
surfaces of the seat and cover, around their entire periphery.
The invention will be understood by reference to the annexed drawing, in which
Fig. 1 is a longitudinal section of a manhole, with a portion of a boiler shell to
which the manhole frame is riveted; Fig. 2 is a plan of the manhole with the
cover shown edgewise in the seat, as when inserted through the same; Fig. 3 is
an elevation of the packing ring with dotted lines showing the shape of the ring
when compressed to force it through the smaller end of the seat; and Fig. 4 is
an edge view of the packing ring.
Figs. 3 and 4 are drawn one half the size of Figs. 1 and 2.

page_text: A designates the manhole frame with inwardly flared conical seat B, and C
designates the shoulder formed around the hole in the frame at the outer edge
of such seat.
C designate notches formed in the shoulder at opposite sides, and extending
into line with the smaller end of the seat.
D designates the cover having conical rim D¹ proportioned at its larger end to
pass through the notches, as shown in Fig. 2.
E designates the packing ring of suitable size externally to fit the seat, and
internally to fit the cover.
The cover is shown with central bolt F extended through a bridge G and
provided with tightening nut H; but two bolts may be used, and in the case of
small hand-holes, any equivalent screw threaded fixtures may be used to draw
the cover to the seat.
The ring is made compressible, and although it cannot be passed through the
seat parallel with the same, it may be inserted within the frame edgewise, like
the cover shown in Fig. 2, and forced through the seat by compressing it into. oval
shape, as indicated by the dotted lines E' in Fig. 3.
In making the joint with such construction, the cover is first inserted through
the seat by turning it edgewise and passing it through the notches C¹, as shown
in Fig. 2.
The ring is then passed through the seat and fitted upon the rim of the cover,
and both are then drawn into the seat, as shown in Fig. 1.
The bridge is then adjusted and the nut H applied to the bolt F. Only a
small amount of taper is formed upon the seat and cover, and the draft of the
nut thus suffices to compress the metal in the ring and thus conform the same
perfectly to the seat and cover, so as to make a perfectly tight joint. In employ-
ing this construction, to close hand-holes or apertures under six inches diameter,
the ring may be readily held in place by contact with the seat, and the shoulder C
is not therefore necessary with such small constructions.
I have therefore claimed the device with and without the shoulder C.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:
1. In a manhole cover, the combination, with the frame A having the inwardly
flared seat B, of the manhole cover D having conical edge D' adapted to pass
through the said scat, the conical metal ring E fitted between the seat and cover,
and means for drawing the cover toward the ring, substantially as herein set forth.
2. In a manhole cover, the combination, with the frame A having the inwardly
flared seat B with shoulder C at its outer end formed with notches C¹ at opposite
sides, of the ring E adapted when compressed to pass between the notches and
fitted to the seat and shoulder, the cover D having conical edge D' adapted to pass
through the notches, and means for drawing the cover toward the ring, sub-
stantially as herein set forth.
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