Improvements in Joints for Earthenware Pipes.
Year: 1892

page_text: Date of Application, 18th May, 1892
Complete Specification Left, 16th Feb., 1893-Accepted, 1st Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in Joints for Earthenware Pipes.
We, HENRY LEWIS DOULTON, Potter, and CHARLES EDWARD MORRIS,
both of Albert Embankment, Lambeth, in the County of Surrey, do hereby declare
the nature of this invention to be as follows:-
The sockets of earthenware pipes are sometimes lined and the pipes tipped with
cement in order that when laid the joints may fit more accurately than is possible
if the earthenware surfaces be allowed to come together.
According to a Patent No. 15248 in the year 1885 the sockets are lined to a
cylindrical form and the tips are made spherical.
This arrangement allows of play in the joint both longitudinally and laterally;
without interfering with the tightness of the joint if truly made but great accuracy
is required.
To avoid the necessity for this extreme accuracy we now make the inner surface
of the cylindrical lining of an elastic material such as vulcanised bitumen.
The diameter of the spherical tip we make slightly greater than that of the
cylindrical lining just to the extent requisite to ensure close contact. The joint is
made by the fitting of the sphere into the elastic cylinder, and the length of the
elastic cylinder is such as to admit of the true fit of the sphere within it in every
position over the whole extent of the freedom allowed to the pipes.
The way in which we make the joint thus differs essentially from the mere
insertion of an elastic ring into the pipe socket as is described for example in a
Specification No. 1552087 and which we do not claim.
In place of tipping the pipe to a spherical form we sometimes make the tip
cylindrical and provide a narrow elastic ring which we fix in the lining of the
socket.
In this case there is full freedom in the joint for longitudinal movement and some
freedom for lateral movement; the latter resulting from the deformation of the
elastic ring under pressure, whereas in the form of our invention first herein
described the freedom for lateral movement is obtained without deformation of the
elastic material except to the extent to compensate the minute inaccuracies of form
unavoidable in manufacture.
Dated this 18th day of May 1892.
CARPMAEL & Co.,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Joints for Earthenware Pipes.
We, HENRY LEWIS DOULTON, Potter, and CHARLES EDWARD MORRIS,
both of Albert Embankment, Lambeth, in the County of Surrey, 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 :-
I
The sockets of earthenware pipes are sometimes lined and the pipes tipped with
cement in order that when laid the joints may fit more accurately than is possible
if the earthenware surfaces be allowed to come together.
According to a Patent No. 152488, the sockets are lined to a cylindrical form
and the tips are made spherical.
This arrangement allows of play in the joint both longitudinally and laterally

page_text: without interfering with the tightness of the joint. Great accuracy is however
required in the manufacture and there is only a small extent of contact between the
joint surfaces.
We now make the inner surface of the cylindrical lining of an elastic material
as is shown by Figure 1 of the annexed drawings, which is a longitudinal section
of part of the joint between two earthenware pipes.
a is the socket of one of the pipes. b is the spigot end of the other pipe. a¹ is
the cement lining to the socket and a² is the elastic material which forms the inner
surface of the socket lining. is the cement tip upon the end of the pipe b; the
contact surface of the tip is spherical.
The diameter of the spherical tip we make slightly greater than that of the
cylindrical lining just to the extent requisite to ensure close contact with the elastic
lining over the whole or the greater part of its surface. The joint is made by the
fitting of the sphere into the elastic lining and the length of the elastic lining is
such as to admit of the true fit of the sphere within it in every position over the
whole extent of the freedom allowed to the pipes.
The necessity for extreme accuracy is thus avoided. Also a lengthened contact
between the joint surfaces is obtained and the joint thereby rendered capable of
withstanding considerable internal or external pressure.
The way in which we make the joint thus differs essentially from the mere
insertion of an elastic ring into the pipe socket where contact would exist in the
normal position of the pipes, as is described for example in a Specification
No. 1552087 which we do not claim.
1
In place of tipping the pipe to a spherical form we sometimes make the tip
cylindrical and provide a narrow elastic ring which we fix in the lining of the
socket. Figure 2 is a longitudinal section of a
In this case there is full freedom in the joint for longitudinal movement and
pipe joint of this construction.
some freedom for lateral movement, the latter resulting from the deformation of
the elastic ring under pressure, whereas in the form of our invention first herein
described the lateral movement causes no deformation of the elastic material until
the end & comes against the bottom of the socket a.
Vulcanized bitumeu may be used for the compressible lining in the socket but in
practice we have found that the most suitable material is plaited cotton of suitable
width and resembling lamp wick; and treated with bituminous matter to render it
waterproof and durable.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. A pipe joint substantially as described in respect to Figure 1 and consisting
of a spherically tipped pipe end and a socket with a cylindrical lining and broad
surface of elastic material giving continuous bearing to the spherical tip as herein
set forth.
2. A pipe joint substantially as described in respect to Figure 2 and consisting of
a cylindrically tipped pipe end and a cylindrical socket with a narrow elastic ring
partially embedded therein as herein set forth.
Dated this 16th day of February 1893