Improvements in or connected with Gates for Railway Crossings and the like.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in or connected with Gates for Railway Crossings and
the like.
I, LEICESTER BRADNEY STEVENS, Engineer, of Darlington Works, Southwark
Bridge Road, in the County of London, do hereby declare the nature of this
invention to be as follows:-
This invention has for its object to construct a gate specially applicable for rail-
way crossings and the like which may be manipulated from a distance and which,
when swung into either of two extreme positions, automatically locks itself in
such position until released by the signalman or other operator in charge of it.
In one arrangement of gate constructed according to this invention the heel
post of the gate terminates downwardly in a vertical pivot shaft resting in a
suitable footstep, and rigidly mounted on the said shaft is a pinion gearing with a
driving spur wheel loosely mounted on a vertical shaft or stud pin and connected
by a suitable lever and rods to an operating wheel or lever in the signal cabin or
clsewhere, the said rods being connected to the said lever by a pin and slot joint
in order to permit of limited independent motion between the rods and lever or
spur wheel. Loosely mounted on the beforementioned stud pin, and above the
driving spur wheel, is a cam disc carrying a cam which engages with a similar
cam on a second cam disc above it, also loosely mounted on the beforementioned
stud pin and free to slide axially on it. The lower cam plate is connected to the
operative rod connections, while the upper cam plate is so connected to the driving
spur wheel as to permit of a limited independent motion between them. Suitable
stops are provided to limit the angle of motion of the upper cam plate and, con-
sequently, of the driving spur wheel also.
The upper cam disc passes under a sleeve slidably mounted on the heel or pivot
shaft so that, as the beforementioned cams engage, the said disc is elevated and
forces the said sleeve up the heel shaft, while the disengagement of the cams
permits the disc and sleeve to fall into their normal positions.
The sliding sleeve is so connected by a rack and pinion, or other suitable gear
connections, to a bolt or latch on the opposite end of the gate, that its upward
motion on the heel shaft is communicated to the said bolt and projects it into its
socket or locking plate.
The action of the apparatus is as follows: The gate being locked in either of
its extreme positions, the first operative movement of the connecting rods causes
the slot in the end of the connecting rod, jointed to the driving spur wheel lever,
to slide on its pin without producing any motion of the wheel, the lower cam disc
at the same time rotating through a sufficient angle to bring the cams into engage-
ment, forcing the upper cam disc and the sliding sleeve on the heel shaft upwards,
and thereby withdrawing the locking bolt from its socket or locking plate. The
driving spur wheel and the two cam discs then rotate together, swinging the

page_text: gate until it reaches its second stationary position, when the motion of the upper
cam disc is arrested by its stop, the further motion of the lower cam disc serving
to slide the cams out of engagement and so permit the beforementioned sliding
sleeve to return, assisted if required by a spring, to its normal position, thereby
operating the bolt to lock the gate. During the locking operation the driving 5
spur wheel remains stationary, the slotted connecting rod end sliding freely on its
pin, as will be readily understood.
Dated this 29th day of October 1896
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Gates for Railway Crossings and
the like.
I, LEICESTER BRADNEY STEVENS, Engineer, of Darlington Works, Southwark
Bridge Road, in the County of London, 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 has for its object to construct a gate specially applicable for rail-
way crossings and the like which may be manipulated from a distance and which,
when swung into either of two extreme positions, automatically locks itself in
such position until released by the signalman or other operator in charge of it.
In the accompanying drawings: Fig. 1 is a sectional side elevation of a gate
provided with controlling mechanism constructed according to this invention,
and Fig. 2 is a plan of the same. Fig. 3 is an elevation of a pair of controlling
cam discs showing their relative positions normally and when in engagement.
The heel post a of a gate terminates downwardly in a vertical pivot shaft b
resting in a footstep c, and rigidly mounted on the said shaft is a pinion d gearing
with a driving spur wheel e loosely mounted on a vertical shaft or stud pin f and
connected by a lever g and rods h to an operating wheel or lever in the signal
cabin or elsewhere, the said rod h being connected to the lever g by means of a
pin and slotted head in order to permit of limited independent motion between
them. Loosely mounted on the beforementioned stud pin f is a cam disc m
carrying cams n which engage with similar and corresponding cams o on a second
cam disc p above it, also loosely mounted on the said stud pin and free to slide
axially thereon. The lower cam disc m is directly connected to the operating rod
connections by means of the lever q and connecting rod r and indirectly to the
spur wheel e through the rod h and lever g, while the upper cam disc is con-
nected to the said spur wheel by means of a carrier pillar s secured in the said spur
wheel and passing through openings in the discs m 7, the upper end of the said
pillar engaging with adjustable tappet screws secured in lugs v in the disc pas
shown. The angular traverse of the upper cam disc p and consequently that of
the spur wheel e is regulated by adjustable tappet levers w. The edge of the
upper cam disc 2 passes beneath a sleeve a slidably mounted on the heel or pivot
shaft b so that, as the beforementioned cams n o engage, the disc p is elevated and
forces the sleeve up the heel shaft while the disengagement of the cams permits
the disc and sleeve to fall into their normal positions. The sleeve is connected
through a rack y pinion z crank aa rod ab and bell crank lever ac to a sliding
bolt ad so that, as the sleeve az is slidden along the shaft b the bolt ad is corres-
pondingly raised or lowered as will be readily understood. A socket or locking

page_text: plate ae is provided into which the bolt ad falls when the gate reaches the
extremity of its angular traverse, the return of the sleeve a being assisted by a
spring af
The action of the apparatus is as follows:-
The gate being locked in one of its extreme positions the first operative move-
ment of the connecting rod h causes the slotted head to slide on its pin i without
producing any motion of the lever g or spur wheel e which motion is further pre-
vented by the locking bolt ad until the head has travelled the whole length of its
slot on the pin i during which motion the cam disc m has been rotated until the
cams no are in full engagement, being centrally above each other, any indepen-
dent forward motion of the upper disc p being prevented by the tappet screw t
and pillar s. The engagement of the cams no raises the upper disc p and with-
draws the bolt ad from its locking plate ae, the further motion of the rod h
rotating the spur wheel e and two cam discs together and swinging the gate until
the tappet stop lever w strikes the sleeve and arrests the further rotation of the
disc p, the further rotation of the rod h carrying forward the spur wheel e and
disc m until the pillars strikes the tappet screw when the cams n are carried out
of engagement with the cams o and permit the disc p and sleeve, assisted by
the spring af to fall into their normal positions, thereby operating the bolt ad
to lock the gate.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is :-
1. In or connected with gates for railway crossings and the like: operating and
controlling mechanism comprising, a spur wheel and pinion connected to operative
rod connections, a cam disc with cams connected to the rod connections, a second
cam disc carrying cams engaging with the first named cams and a sleeve sliding
on the heel shaft of the gate and connected to a locking bolt, the whole substan-
tially as described.
2. In or connected with gates for railway crossings and the like: the com-
bination of a sleeve a sliding on a heel shaft b, a rack y, pinion z, crank aa, rod ab,
bell crank lever ac, sliding bolt ad and locking plate ac, substantially as
described.
3. In or connected with gates for railway crossings and the like as described:
connecting the operating spur wheel and lower cam disc to the operating rods so
as to give the cam disc an initial independent motion while the driving spur wheel
remains stationary, and thereby effect an initial engagement of the cams to with-
draw the locking bolt before the gearing is operated to swing the gate.
4. In or connected with gates for railway crossings and the like as described,
connecting the upper cam disc to the driving spur wheel so as to give limited
angular play to permit of the disengagement of the cams at the end of each
traverse and thereby permit the locking bolt to fall into its socket or plate.
5. The combination with the spur wheel e and carrier pillars of cam disc ?
and adjustable tappet screws t substantially as described.
6. The combination with the cam disc of the adjustable tappet levers w
secured thereto, substantially as described for the purpose set forth.
7. The improvements in or connected with gates for railway crossings and the
like, the whole arranged constructed and operating substantially as described
and shown.
Dated this 20th day of T... 1907
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.