Improved Protective Appliances for Pipe Connections and Fittings, and for other purposes.
Year: 1894

page_text: Date of Application, 20.h June, 1894-1ccepted, 25th Aug., 1894
COMPLETE SPECIFICATION.
Improved Protective Appliances for Pipe Connections and Fittings,
and for other purposes.
I, JOSEPH CRAWHALL CHAPMAN, C.E., and Chartered Patent Agent, of
70, Chancery Lane, in the County of London, do hereby declare the nature of
this invention, which has been communicated to me from abroad by George
James Cox, Chief Inspector of the Metropolitan Gas Company, 186, Flinders
Street, Melbourne, Australia, and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement:-
My invention has for its object to provide simple, secure, and reliable appliances
for preventing fraudulent access to the couplings or caps of pipes and meters or
other apparatus for conveying, measuring, registering, or enclosing valuable liquids,
fluids, or other matter such as gas, water, compressed air, steam, electric conductors,
and so forth, and for protecting same from use otherwise than is intended, whereby
such contents might be abstracted or tampered with without due registration or
payment. Couplings or nuts as ordinarily used on gas or water pipes, meters, etc.,
from their shape are easily disconnectable by wrenches or spanners so that the
contents of the pipe can be abstracted.
For securely protecting such coupling devices, according to my invention [
provide a casing of brass, malleable iron, or other suitable metal, or if it be used
for electrical purposes it may be of earthenware, vulcanite, or other insulating
material. The casing is of such size and shape as to enclose the coupling or
connection and fit on and around same in such manner as to prevent the insertion
of any tool to the enclosed fitting. The casing is generally formed in two parts
hinged together in suitable manner so as to open, pass over, and enclose the fitting
after the joint is made. The other ends of the two parts are provided with a
special lock consisting essentially of a recessed chamber or chambers and a screwed
tap pin adapted to lock the two parts together and having two or more threads
running in opposite directions and operated by a specially constructed socket key.
This key is not easy to make, and since no other tool will fix or release the
protector, fraudulent interference is very difficult, if not impossible, without proper
knowledge and skill.
I will fully describe my invention in reference to the accompanying drawing
which illustrates my invention as applied to gas or water connections.
Figure 1 is a plan of the protector as applied to the main cock coupling of a gas
service pipe, the locking portion being shown in section and the enclosed coupling
being shown in dotted lines.
Fig
igure 2 is a left side elevation of the protector,
Figure 3 is a front elevation of the protector showing the lock in section.
Figure 4 is an elevation of a modified form of protector, the lock being in section,
and Figure 5 is a plan thereof;
Figures 6 and 7 illustrate the keys hereinafter referred to.
Similar letters refer to similar parts in all the figures.
The protector is made in two parts A A' hinged together by a pin as at a
or by cross hooks as at a', or in any suitable way; cach part A A' has a top
and bottom flange a leaving an opening a³ adapted to fit well upon the pipe
outside each end of the coupling to be protected. B and C are projecting lugs
cast on the parts A A', they are bored out so as to form chambers bc to such
depth as to leave a sufficient body of metal at the base of each; this is tapped

page_text: as one nut and a pin D is formed with its central portion screwed with a right
hand thread so as to run freely through from band e and lock the two lugs B
and C together; the two end portions of D are reduced in diameter and
screwed each with left handed threads as shown in Figures 1 and 3. The
internal threads of the socket key S, Figure 6 is also left handed and adapted
to fit the two ends of pin D.
To lock the protector together, one end of the pin D is first screwed into
the socket teal S and the two meeting ends of the casing Bare held in position
round the fitting to be protected. The tool S with the pin D is then inserted
into the recess in B or C and turned with a right handed screwing motion,
causing the right handed thread on D to enter the tapping in B and C; when
that portion of the screw is wholly or partly home a continuation of the right
hand movement will cause the left handed tool to unscrew and run off that end
of the pin D. The tool is then inserted and screwed in a left hand direction
on to the other end of the pin in the opposite recess and this draws the
right hand thrend of D tighter into its position, a sharp turn in the opposite
direction releases the tool, leaving the pin D firmly locking the protector
together. The locking pin D when in position is protected from interference
by any ordinary means, by being well within the recesses and c, and is also
made more secure by being rounded at the ends as shown.
CASCA
To unlock the protector it is necessary to insert the socket tool S into the
same recess as that first used for locking, and with a left hand motion screw
the tool on the head of D, continuing to screw until the pin D is withdrawn
from its right handed nuts or tapping in B and C and remains in the tool
ready for screwing the protector together again when required and thus pre-
venting its getting mislaid. Figures 4 and 5 illustrate a modification of the
above arrangement in which the locking pin D is arranged at right angles to
the one previously described, the lugs B C lapping over each other instead of
being butt-jointed, one lug C only is shown tapped, but I may in some
tap both C and B as before described; the pin D in this arrangement has a
change of thread at one end only, and may be provided with a collar d or
otherwise to regulate the distance it shall screw into the lug C. For this form
of my invention the tool, Figure 7, is employed, it has a cross handle & at
about the centre of its length, and a screwed socket at each end (preferably of
different sizes for facility in manipulation) the one as before with a left hand
thread, and the other with right landed internal thread. This second
socket is used to screw the pin D home after it has been inserted and screwed
in with the socket until the tool has run off. When the apparatus is to be
unlocked, the sockets of the key is to be applied to the head of the pin, and the
pin Dunscrewed and withdrawn as previously described.
The apparatus will be preferably constructed as herein generally described, but
I do not confine myself to the precise details specified, as may if desirable
reverse the combination of opposite running threads as employed for the purpose
of this invention. It will also be seen that the apparatus is equally applicable to
other purposes than those to which it has been more specifically described herein,
and may be varied as may be necessary or beneficial without departing from the
nature of my invention.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I declare that what 1
claim is -
1. A protective appliance for pipe connections and fittings and for other purposes
consisting of a two part hinged casing adapted to enclose the coupling or other
device to be protected and having meeting lugs recessed and tapped to receive a
screwed locking pin such as D of two or more different diameters and with a
combination of threads running in different directions, adapted to lock and release
the casing by a special key substantially as above set forth.

page_text: 2. In a protector such as is above referred to the combination of the tapped
meeting lugs and a screw tap pin and special key therefor constructed substantially
as and for the purposes above set forth.
Dated this 20th day of June 1894.
J. C. CHAPMAN,
Chartered Patent Agent.