Improvements in Centre Valves Employed in Connection with Gas Purifiers.
Year: 1885

page_text: COMPLETE SPECIFICATION..
Improvements in Centre Valves Employed in Connection with
Gas Purifiers.
I, ROBERT DEMPSTER Junior, of the firm of R and J Dempster, of Newton,
Heath, Manchester, Gas Engineers, do hereby declare the nature of my invention
for IMPROVEMENTS IN CENTRE VALVES EMPLOYED IN CONNECTION WITH GAS
PURIFIERS," and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
The improvements relate to the ordinary form of dry faced centre valves, mostly,
in use, having four inlets and four outlets for a set of four purifiers, but which are
ordinarily so constructed that, one of the purifiers is cut out of the circuit, and thus
remains idle for cleaning purposes.
Specially arranged centre valves have been constructed for. the purpose of
enabling the four purifiers to be in use simultaneously-as is instanced by my
specification number 1581 of the year 1884, and the object of this my present.
invention is more especially to enable the ordinary centre valve to be altered or
converted so that this arrangement can be effected at will therein.
To accomplish this and to effect my improvements, I take the top or cover of the
ordinary valve (generally known in the trade as Cockey's or Thorncliffe's dry
faced centre valves) and face the same over the upper surface, or such portion
thereof as is necessary; or a facing piece may be attached thereto. I then cut
through the metal and take out the concentric ring, corresponding with the con-
centric opening inside, and insert two extra divisions or diaphrams in the valve,
and also cut three outlet holes in the cover to correspond with openings in the
valve which are contiguous. I then form a partial cap or cover for the opening
thus formed, capable of turning or sliding to and fro the requisite distance by
turning upon the centre, in such manner that by bringing the two extra gas-ways
into circuit the fourth purifier is able to be worked with the other three when
desired.
A hand lever is attached to the partial upper cover, or suitable gearing may be
provided, for the purpose of giving the requisite motion thereto; and stops and
'

page_text: catches
position.
may
be added for the purpose of holding or securing the partial cover in
It is obvious that centre valves can be constructed new in the form described,
and that variations in detail may be made without departing from the peculiar
character of the invention which mainly consists in attaching a partial moveable
cover to and upon the ordinary cover, with openings for entry and exit of the gas, in
such manner that the same will enable the fourth purifier to be put in or cut out of
circuit at will, whether such valves be constructed new in this form or are altered
or converted from those now in use.
But that the improvements may be better understood I will by the aid of the
accompanying drawings proceed more fully to describe means emnloved by me.
Fig. 1. shews elevation and Fig. 2. a plan of centre valve constructed or con-
verted in accordance with my improvements. Fig. 3. is a vertical section on
line K L, and Fig. 4. is partly in section and partly in plan, the sectional portion
being on line A B. Fig. 5. is a plan on line CD, and shews the openings in the
ordinary cover when the new or extra partial cover is removed. Fig. 6. is a
section on line E F, and shews the extra diaphrams or partitions inserted; and
Fig. 7. is a section on line GH.
The same letters hereinafter employed indicate corresponding parts wherever
they occur.
a, a, is the extra or partial cover which forms the main feature of this my
present invention, and which constitutes an additional or supplementary cover to
the main or general cover b, b.
The cover b, b, is capable of being rotated through the whole circle as is well
understood, by means of the pinion wheel b¹ upon the spindle 62 acting upon the
toothed wheel attached to or forming a part of such cover b, b.
It will be seen that this cover in its movements will carry with it the
supplementary cover a, a, which may also be actuated, by means of the toothed
wheel a', upon the spindle a², geared into the toothed segment attached to or
forming part of a, a, or a hand lever may be employed in lieu of this arrangement.
This supplementary cover may thus have given to it a to and fro motion upon the
main cover b, b, and its function is to take the fourth purifier in or out of circuit..
When rotated to one side, such purifier is enabled to be in operation, whereas,
when rotated to the other side, it is cut off.
b³, are the three openings cut in the ordinary cover to form communication with
the supplementary cover, and 6' is the annular opening communicating with the
outlet.
C, C, are the two extra diaphrams required in the convertion of centre valves of
the old type, but which may be made solid in the case of new constructions.
The arrows indicate the directions in which the gas travels, but the apparatus
may be so arranged as to reverse the direction of flow.
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
1st The cutting of the cover of a centre valve of the character herein before
named with the annular opening or openings 6, and the three openings 6³, as
shewn in Figs. 4 and 5, and fitting the same on prepared surfaces with a partial or
supplemental cover a, a, enabling the fourth purifier to be shunted either in or out
of circuit in manner substantially as shown and described.
2nd The application of a supplemental cover to a centre valve capable of being
rotated to and fro thereon by toothed gearing or hand lever so that the rotation

page_text: in one direction will shut off communication with one of the purifiers, and rotation
in the other direction will open communication therewith, substantially as shewn
and described.
3rd The construction of centre valves such as hereinbefore described with extra
partial or supplemental covers upon and in connection with the main or ordinary
covers thereof for the purpose and in manner substantially as shown and
described.