Improvements in Prepayment Gas Meters.
Year: 1895

page_text: Date of Application, 28th Nov., 1895
Complete Specification Left, 28th Aug., 1896-Accepted, 3rd Oct., 1836
Improvements in Prepayment Gas Meters.
WILLIAM COWAN, and WILLIAM HENRY COWAN, Buccleuch Street Works,
Edinburgh, Midlothian, N.B. Gas Meter Manufacturers &c. do hereby declare the
nature of this invention to be as follows:-
The object of this invention is to prevent a difficulty or inconvenience which
may arise in connection with coin freed, prepayment gas meters when the stop
valve, though closed, is not gas tight. In such a case the continued passage of
even a very small quantity of gas may result in the forcing and derangement of
the prepayment mechanism, and it is to obviate this, that the present invention
has been devised.
The means employed consist of so constructing one or other of the gearing
worms or wheels that its "hold" or "grip" upon its shaft is due to a spring
which is capable of being forced and the wheel or worm thereby rendered capable
of being "held" by the prepayment mechanism whilst the driving or other shaft
which carries the worm or wheel continues to revolve. When the spring is applied
in connection with a worm, it is desirable to attach thereto a notched, or toothed,
disc, against, or into the edge of, which, a travelling stud, bar, or other suitable
projection comes, on each occasion that the valve is closed by the mechanism.
Dated this 27th day of November 1895.
WILLIAM COWAN.
W. HENRY COWAN.
WILLIAM COWAN and WILLIAM HENRY COWAN, Buccleuch Street Works,
Edinburgh, N.B. Gas Meter Manufacturers, 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:-
This invention relates to improvements in prepayment gas meters and has for its
object to prevent a difficulty or inconvenience which may arise in connection with
coin freed prepayment gas meters when the stop valve though closed, is not gas
tight. In such cases the continued passage of even a very small quantity of gas
may result in the forcing and derangement of the prepayment mechanism and it is
to obviate this that the present invention has been devised.
But in order that our invention may be more readily understood and easily
carried into effect we will proceed to describe the same with reference to the
accompanying drawings in which
Figure 1 is an elevation and
Figure 2 a plan showing our invention applied to the mechanism described in the
Specification of our prior British Patent No. 21108 of 3rd November 1894.
In carrying out our invention we construct one of the gearing worms A of the
meter mechanism so that its "hold" or "grip" upon its shaft B is due to a spring b
Price Sd 1

page_text: which is capable of being forced, in order to enable the worm A to be "held " by
the prepayment mechanism whilst the driving shaft B which carries the worm A
continues to revolve.
The said worm A is also provided with a notched or toothed disc a against or
into the edge of which a travelling stud or bar a', mounted upon the travelling
tube C which carries the valve closing track C₁, comes on each occasion that the
valve is closed. The said stud or bar a' is preferably provided with a slot a² and
secured by means of screws a³ so that it is capable of being adjusted as required.
The said worm A is kept in contact with the spring 6 by a collar 6 secured to
the shaft B.
The action of the foregoing is such that as soon as the valve is closed by the
track the stud or bar a' engages with the teeth upon the disc a of the worm A
thereby preventing, should the valve be at all leaky, any forcing or derangement
of the prepayment mechanism.
Or in place of employing the worm we may mount one of the wheels into which
the worm works, in a similar manner, so that when any resistance is offered by the
prepayment mechanism, the wheel can be revolved by itself, and therefore do no
damage to the mechanism.
Our invention is of course equally applicable to other kinds of prepayment
mechanism apart from that already described and to both wet and dry gas meters.
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 :-
1st. In prepayment coin freed gas meters, the employment of a slip worm or a
slip wheel, to protect the mechanism from being forced or deranged, in the event
of the valve, after being closed, continuing to pass gas, substantially as hereinbefore
described and shown in the accompanying drawings.
2nd. In prepayment coin freed gas meters, the combination with the slip worm
claimed in Claim 1, of a notched or toothed disc fixed to this worm and of an
advancing stud or bar to hold disc and worm against the shaft in the event of the
valve passing gas after being closed, substantially as herein before described and
shown in the accompanying drawings.
Dated this 27th day of August. 1896
JOHNSONS,
115 St. Vincent Street, Glasgow, Applicants' Agents.