Improvements in Opening Bridges and in Mechanism for Operating the same.
Year: 1889

page_text: Date of Application, 4th Oct.. 1889
Complete Specification Left, 4th July, 1890-Accepted, 9th Aug., 1890
PROVISIONAL SPECIFICATION.
Improvements in Opening Bridges and in Mechanism for Operating
the same.
I FERDINAND HUDLESTON of Mersey Railway Buildings, James Street Liverpool
in the County of Lancaster Engineer do hereby declare the nature of this invention
to be as follows:-
According to this invention two contiguous spans of a girder bridge are opened
simultaneously. The girders across the two spans are continuous and are hinged to
their intermediate pier or other support, about a horizontal axis set transversely to
the bridge.
When it is required to open the bridge, these girders are turned upon their hinges,
one end moving down and the other up, so that the girders and roadway of one span
act as a counterweight those of the other.
For closing the bridge the movement is reversed. The opening and closing processes
may be performed either manually or by power. A simple method of using power
for the purpose is to couple a piston working in a hydraulic cylinder to the hinged
girders by means of a connecting rod. Various other methods may also be employed
according to circumstances. The lifting end of the bridge rests, when the bridge is
closed, upon fixed supports, and the falling end may be carried by moveable bearings
which may be fitted with gear for taking up the deflection of the girders. These
bearings are withdrawn clear of the girders when it is required to open the bridge.
When signals are employed for regulating the traffic over bridges constructed
according to the present improvements the signals may be made to interlock with the
moveable bearings so as to prevent them from being withdrawn except when the
signals are at danger; and these bearings may be made to interlock with
the mechanism for turning the bridge about its hinges, so that this mechanism cannot
be brought into action except when the moveable bearings stand clear of the falling
end of the bridge.
11 1000
COMPLETE SPECIFICATION.
Improvements in Opening Bridges and in Mechanism for Operating
the same.
I FERDINAND HUDLESTON of Mersey Railway Buildings, James Street Liverpool
in the County of Lancaster, Engineer do hereby declare the nature of this invention
and in what manner the same is to be perforined, to be particularly described and
ascertained in and by the following statement and accompanying Drawings :-
'-
According to this invention, two contiguous spans of a girder bridge are opened
simultaneously. The girders across the two spans are continuous, and are hinged to
their intermediate pier or other support, about a horizontal axis set transversely to the
bridge. When it is required to open the bridge, these girders are turned upon their
hinges, one end moving down and the other up, so that the girders and roadway of
one span act as a counterweight to those of the other. For closing the bridge the
moveinent is reversed. The opening and closing processes may be performed either
manually, or by power. A simple method of using power for the purpose is to couple
a piston working in a hydraulic cylinder to the hinged girders by means of a
connecting rod. Various other methods may also be employed according to circum-
stances. The lifting end of the bridge rests, when the bridge is closed, upon fixed
supports; and the falling end may be carried by movable bearings, which may he

page_text: fitted with gear for taking up the deflection of the girders. These bearings are with-
drawn clear of the girders when it is required to open the bridge.
The accompanying Drawings illustrate a method of performing the invention in
connection with a railway bridge carried on wrought iron pillars
Fig. A is a longitudinal elevation showing the bridge open and
:―
Fig. Ba longitudinal section showing the bridge closed; mechanism being shown
in each view for operating the bridge.
Fig. C is a transverse section of the bridge, but it does not show any of the features
peculiar to the present invention.
Fig. D is an enlarged longitudinal section of one of the pillars to which the opening
girders are hinged, showing the mechanism for opening and closing the bridge, and
Fig. E is a like section of another pillar showing the movable bearings at the
falling end of the bridge and the gear for operating the same, and taking up the
deflection of the girders.
Each
1. is one of a pair of opening girders-2 one of a pair of pillars to which the
opening girders are hinged-3. one of a pair of pillars which support the lifting ends
of the girders and 31 one of a pair of pillars which support their falling ends when
the bridge is closed; and 4.4 are fixed girders belonging to adjacent parts of the
bridge 5. 5 are transverse beams carrying the roadway 6.6 longitudinal sleepers
and 7. 7 rails laid thereon. It will be seen that in the example shown by the Drawings
the span of the falling end of the opening bridge is smaller than that. of the lifting
end, and to make the weights of the two spans balance each other suitably, a balance
weight 8 is added to the falling, or shorter end. Each opening girder is provided at
its underside with a plummer block 9. securely attached thereto. These plummer
blocks stand respectively within the two pillars on which the opening girders are
hinged and they work upon horizontal pins 10. held in the pillars. The pins and
plummer blocks thus form hinges for the opening girders to pivot upon.
opening girder is also provided at its underside with an arm or bracket 11. which is
coupled with one end of a connecting rod 12.-the other end of which takes into a
cross head 13. working along a guide bar 14 fixed to the pillar 2.-The crosshead is
fitted on the end of a piston rod 15. which works in a double acting hydraulic
cylinder 16. The bridge is opened by admitting water under pressure to the lower
ends of the cylinders on the pillars 2. 2. and is closed by admitting the water to the upper
ends of the cylinders. For supporting the falling end of the bridge when in the closed
position, each opening girder provided at this end with a respective movable
bearing 17. which consists of a strong plate hinged at one edge on a pin 18. held in
the pillar 31. When in the closed position, the edge of the plate which supports the
girder, through the intervening balance weight 8. is upheld by a rocker 19. hinged
upon a pin 20. and resting also upon a concave bearing 21. secured firmly to the
pillar 3 The rocker is actuated by hydraulic mechanism similar to that described for
opening and closing the bridge. The position assumed by the movable bearings and
rockers for allowing the bridge to be opened is clearly shown by dotted lines in Fig. E,
and from these it will be seen that the movable bearings are in this position clear of
the girders, and that an upward movement of the rockers will raise the lowered edges
of the movable bearings and cause them to press upon the underside of the balance
weight 8. so as to take up the deflection which there will be in the girders when their
ends are unsupported. The lifting ends of the opening girders rest securely on the
pillars 3, when the bridge is closed.
I do not confine myself to the precise methods herein shown and described of making
the hinges and movable bearings of the bridges, and of operating these bearings and
the bridges, it being obvious that modifications may be made therein, to suit different
circumstances, without departing from the nature of my invention.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
1. The construction of an opening girder bridge, whereby two contiguous spans

page_text: may be opened or closed simultaneously, the girders extending across the two spans,
being continuous and being hinged upon the intermediate pier or other support of the
two spans, so that when opening the bridge the girders ascend at one end, and
descend at the other, the weight of one of the spans acting as a counterweight to
that of the other, substantially as described.
2. In combination with opening bridges such as described in claim 1. the employ-
ment of movable bearings for supporting the falling ends of the girders and for
taking up the deflection therein substantially as described.
3. In combination with opening bridges such as described in claim 1. the arrange-
ment of movable bearings and of mechanism for operating the same, the arrangement
of mechanism for opening and closing the bridges, and the arrangement of hinges for
the girders to pivot upon, all substantially as shown and described.
Dated this Third day of July 1890
HY. C. CARVER.