Improvements in Mitre-valves, Clack-valves and the like and their Seatings.
Year: 1898

page_text: Date of Application, 28th Oct., 1898
Complete Specification Left, 10th Jan., 1899-Accepted, 11th Feb., 1899
Improvements in Mitre-valves, Clack-valves and the like and their
Seatings.
I, JOHN VICKERS, of 13, Holker Street, Barrow-in-Furness, in the County of
Lancashire, Engineer, do hereby declare the nature of this invention to be as
follows;
-
This invention relates to an improved form of valve and seat of what is generally
known as the mitre or mushroom type, that is, a valve where the working seat of
the head is in the form of a frustrum of a cone or made in the form of a mitre
and fitting into a bush with a correspondingly shaped seat bored therein.
In my invention I make the crown of the valve of somewhat larger diameter
than usual, and upon its under face in addition to the usual singly mitred face I
make a series of one or more circumferential depressions or angular grooves or
ridges around the said face.
In the face of the seat I also make similar grooves and ridges into which those
upon the under face of the head or crown of the valve fit when the valve is on
its seat.
Both series of grooves and ridges are ground to fit each other so that instead of
the usual single mitres, my valve has a series of mitres, thus ensuring a more
perfectly steam-tight fit than hitherto, in consequence of the greater number of
mitred surfaces. This is of great importance in the matter of safety-valves where
a perfect fit is necessary to prevent leakage, and moreover the angular grooves upon
the under side of the valve form an impediment to the escaping steam when the
valve is raised from its seat, thus rendering the usual lip unnecessary. When
this type of valve is used in pumps or as a clack-valve upon the feed-pipe of a
boiler; the water lodging within the aforesaid grooves, acts as a cushion upon the
downward stroke of the valve thus preventing undue wear and tear and diminishing
or entirely preventing the noise usually attending the working of ordinary pump
valves.
The grooves and ridges may, if desired, be rounded instead of angular.
I do not confine myself to any particular number of grooves.
The valves made according to my invention may be used for any purpose where
ordinary valves of similar type are required.
Dated the 28th day of October 1898.
PHILLIPS & LEIGH,
Agents for the Applicant.

page_text: manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
--
This invention relates to an improved form of valve and seat of what is generally
known as the mitre or mushroom type, that is, a valve where the working seat of
the head is in the form of a frustrum of a cone or made in the form of a mitre
and fitting plug or stopper-like into a bush with a correspondingly shaped seat
bored therein.
In order that my invention may be understood, I will now proceed to describe
it in detail with reference to the accompanying drawings illustrating it, and in
which:
Figure 1 is an elevation partly in section of the safety valve and its seat; the
plug of the valve being shewn raised or off the seat for clearness' sake.
Figure 2 is a vertical section of the seat alone; shewing the circular grooves or
recesses therein, and
Figure 3 is a top plan of Figure 2.
According to my invention I make the crown a of the valve of somewhat
diameter than usual, and upon its under surface in addition to the usual singly-
mitred face b, I make one or more circumferential depressions or angular grooves
or ridges c, d, around the said face, concentric and preferably, but not necessarily
with sides at the same angle as the usual bevel face. In the face of the seat I also
make similar extra grooves and ridges c, d, into which those c, d, upon the under
face of the head or crown a of the valve accurately engage and fit when the valve
is on its seat.
Both series of grooves and ridges are ground to fit each other steam-tight so
that instead of the usual single mitres, my valve has a series of mitres, thus
ensuring a more perfectly steam-tight fit than hitherto, in consequence of the
greater number of mitred surfaces. This is of great importance in the matter of
safety-valves where a perfect fit is necessary to prevent leakage, and moreover the
angular grooves c, d, upon the under side of the valve form an impediment to the
escaping steam when the valve is raised from its seat, thus rendering the usual lip
unnecessary. When this type of valve is used in pumps or as a clack-valve upon
the feed-pipe of a boiler, the water lodging within the aforesaid grooves c¹, d¹, acts
as a cushion upon the downward stroke of the valve thus preventing undue wear
and tear and diminishing or entirely preventing the noise usually attending the
working of ordinary pump valves.
The grooves c, d, and c¹, d¹, and ridges may, if desired, be rounded instead of
angular.
I do not confine myself to any particular number of grooves in either the valve
or its seat.
Valves made according to my invention may be used for any purpose where
ordinary valves of similar type are required and with the advantage above
explained.
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. A valve of the mitre-plug or stopper type, having in addition to the ordinary
mitre or bevel working face, one or more concentric grooves outside the ordinary
working face, said groove or grooves having sloping sides and presenting an
additional working face or faces substantially as described and illustrated.
2. A seat for a valve of the mitre-plug or stopper type, having in addition to
the ordinary mitre or bevel face, one or more concentric grooves outside the
ordinary working face, said groove or grooves having sloping sides presenting an
additional working face or faces, substantially as described and illustrated.
3. The combination of a valve plug and seat therefor, each having in addition
to the ordinary mitre or bevel working faces one or more concentric grooves outside

page_text: the ordinary working faces, said groove or grooves having sloping sides and pre-
senting additional working faces, substantially as and for the purpose described
and set forth.
Dated this 10th day of January 1899.
PHILLIPS & LEIGH,
No. 22, Southampton Buildings, Chancery Lane, W.C.,
Agents for the Applicant.