Improvements in Pneumatically Worked Electric Switches.
Year: 1897

page_text: Date of Application, 1st June, 1897
Complete Specification Left, 1st Mar., 1898-Accepted, 16th Apr.,
1898
PROVISIONAL SPECIFICATION.
Improvements in Pneumatically Worked Electric Switches.
We, SIEMENS BROTHERS & Co., LIMITED, of 12, Queen Anne's Gate, West-
minster, S. W., Electrical Engineers, and ALFRED ERNEST LE ROSSIGNOL, of 14,
Vicarage Gate, Kensington, W., Electrical Engineer, do hereby declare the nature
of this invention to be as follows: --
This invention relates to apparatus for controlling the operation of pneumatically
worked electric switches so that they must make and break the required contacts
in certain pre-determined order, as for example, in the starting of a number of
electric motors.
For this purpose a number of vertical pneumatic cylinders are arranged in a
row at equal distances apart each being provided with a vertical slide valve. Each
piston rod passes down through a stuffing box and carries at its lower end an
insulated cross bar which when the piston is in its highest and lowest positions
fornis a conducting bridge between two terminal contacts. The slide case of each
cylinder has an inlet for compressed air near each end and from its middle an
exhaust passage leads to outlets close to the upper and lower contact terminals,
so that when contact is broken the puff of exhaust air prevents sparking.
Each piston rod, which passes up through a stuffing box carries at its upper end
a crosshead from the front of which a rod extends downwards to a guide on the
front side of the cylinder and has there a projecting handle for moving the piston up
or down by hand when required. From the back of each crosshead a pin projects
into a vertical guide groove formed in the face of a horizontal slide which can be
moved to and fro by a rack and pinion, worked by hand, along with a lower slide
having in its face horizontal and inclined grooves in which are engaged pins pro-
jécting from the slide rods. The vertical grooves in which the pins of the cross-
heads work are connected by horizontal grooves at their upper and lower ends, and
the inclines of the grooves in the lower slide are so arranged that as the horizontal
slides are moved step by step, the slide valves of the cylinders are moved in certain
order causing the pistons to make their strokes.
When any piston has made its stroke, the pin in its crosshead having entered
the horizontal part of the groove in which it is engaged, it cannot move up or
down again until the horizontally moving slide has brought a vertical groove in
line with the pin, and thus each switch is locked in position until the horizontal
slides have been moved to that part of their course where the switch is unlocked
and moved by the air pressure acting upon the piston belonging to it.
Although both the horizontal slides may move together as one piece, it is preferred
to make the lower slide separate and movable with a little play between stops on
the upper slide. Thus the lower slide being worked by the rack and pinion, moves
a little before moving the upper slide.
Dated this 1st day of June 1897.
ABEL & IMRAY,
Agents for the Applicants.

page_text: Improvements in Pneumatically Worked Electric Switches.
We, SIEMENS BROTHERS & Co., LIMITED, of 12, Queen Anne's Gate, West-
minster, S.W., Electrical Engineers, and ALFRED ERNEST LE ROSSIGNOL, of 14,
Vicarage Gate, Kensington, W., Electrical Engineer, do hereby declare the nature
of this invention and in what manner the same is to be performed to be particu-
larly described and ascertained in and by the following statement: -
This invention relates to apparatus for controlling the operation of pneumatically
worked electric switches so that they must make and break the required contacts
in certain predetermined order as, for example, in the starting of a number of
electric motors.
**
Fig. 1 of the accompanying drawings is an elevation and Fig. 2 is a vertical_
section of apparatus for this purpose.
Fig. 3 is a vertical section and Fig. 4 is a plan of a modified form in which the
parts are circularly arranged.
T
...A7
Referring first to Figs. 1 and 2, a number of pneumatic cylinders A¹ A².
are arranged in a row at equal distances apart each provided with a vertical slide
valve, B being a rod with two pistons fixed on it working in a cylindrical bore
supplied with compressed air by ports 61 at its ends and having an exhaust port 62
at its middle; from it oblique ports a lead to the ends of the cylinder A.
Each piston rod C passes down through a stuffing box and carries at its lower
end an insulated cross bar c, which, when the piston is in its highest and lowest
positions forms a conducting bridge between two terminal contacts D E or D' E.
The exhaust port 62 communicates by a passage 63 with two outlets e e¹ near the
terminals E E¹ respectively, so that when contact is broken at either of these the
puff of exhaust air from the outlet prevents sparking.
Each piston rod r' which passes up through a stuffing box, carries at its upper
end a cross head f from the front of which a rod extends downwards to a guide
on the front of the cylinder A and then has a handle f¹ for moving the piston up
or down by hand when required. From the back of each crosshead f a pin f² pro-
jects into a guide groove y formed in the face of a horizontal slide G which can
be moved to and fro by a rack and pinion H worked by hand along with a lower
slide K having in its face horizontal and inclined grooves k in which are engaged
the heads 4 of the slide rods.
+
The vertical grooves gin which the pins f move are connected at their upper
and lower ends by horizontal grooves g₁ g², and the inclines of the grooves kare
so arranged that as the slides G and K are moved the slide valves B are moved up
and down in certain order determined by the relative positions of the inclines, and
the pistons are thus caused to make their up and down strokes making and break-
ing the contacts at D E, D₁ E in corresponding order. When any piston has
made its stroke, say for instance that the piston of A has made its down stroke,
then its pin f having reached the horizontal part 2 of the groove in G, it cannot 4
move up again until the movement of the slide G has brought a vertical groove g¹
in line with the pin f, and as this happens for each of the pistons in its order, each
of the switches is thus locked in position until the slides G and K reach that part
of their stroke where an incline of k moves the slide valve of the cylinder belong-
ing to the switch and at the same time or shortly afterwards a vertical groove ġ¹ is 4
presented to the pin f allowing the piston to make its up or its down stroke as the
case may be..
The two slides G and K may move together as one piece, the lower slide K which
operates the slide valves may be fitted to slide on the upper slide G which controls

page_text: the pistons with a little play between stops, so that the slide K, when worked by
the rack and pinion begins its stroke in either direction a little before the slide G.
As shewn in Figs. 3 and 4, the cylinders are arranged circularly around a central
post around the upper part M of which as an axis the slides G and K can be turned
partly round in either direction by a hand lever L moving between stops m m.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, we declare that what we
claim is:-
Apparatus for controlling the operation of pneumatically worked electric switches
substantially as described with reference to the drawings.
D
1
1
1000
ABEL & IMRAY,
Agents for the Applicants.