A New or Improved Hinged Expansion-gear for Bridges, Piers, Girder-work, Roofing, and such like Purposes.
Year: 1889

page_text: Date of Application, 12th Nov., 1889
Complete Specification Left, 6th Aug., 1890-Accepted, 1st Nov., 1890
PROVISIONAL SPECIFICATION.
A New or Improved Hinged Expansion-gear for Bridges, Piers,
Girder-work, Roofing, and such like Purposes.
We CHARLES JOHN WESTWOOD and HARRY RIGBY, Civil Engineers, both of Napier
Yard, Millwall in the County of Middlesex, do hereby declare the nature of this
invention to be as follows:
This invention relates to certain new or improved hinged expansion gear for bridges,
piers, girder-work, roofing and such like purposes the objects being; (1), to prevent
the bearing at the expansion end of the structure from becoming oxidized, silted-up,
concreted or fixed in any way by the action of blown dust, rubbish, oxidation, or
chemical action, as of the atmosphere or sea water or such like foreign or corrosivo
matter, as is found to be the case and to take place where roller gear or sliding bed
and bearing plates are used; (2), to give a perfectly free scope for expansion or
contraction to the structure; and, (3), to reduce the cost in material, fitting, and for
repairs as compared with the generally accepted roller goar or sliding plates, and
reducing the bearing or machined surfaces to about one fourth of the usual area.
In carrying this invention into effect we proceed as follows: A lower and upper
saddle-plate is provided and a double endod knuckle block will be employed and be
set in between the two saddle plates so forming what is substantially a free and double
hinge. The top and bottom bearing surfaces of the knuckle are rounded and
machined as also will be the receiving saddles, correspondingly.
In using this improved gear the lower or bed-saddle-plate will be fixed to the pier,
abutment or whatever attachment is provided and the upper saddle-plate will be
attached to the main girders of the bridge or such structure, and the double
knuckle block will be disposed between the two, oppositely arranged, saddle-plates
bearings.
Under the effect of expansion or contraction the double knuckle-block will then work
forward or backward to the extent necessary and following the variations of tem-
perature which will affect the structure.
In "setting" this gear in, say, low temperature the knuckle-block will be set with
its central line out of the perpendicular and with the proper inclination of said central
line towards the fixed end of the structure, and in a temperature higher than the
normal one the "setting" will be reversely done, that is, with the centre line of
the knuckle-block inclined from the perpendicular, away from the fixed end of the
structure.
Although this expansion fitting is described in this Specification in a certain manner,
it may be varied in numerous ways in either construction, material employed, or
design of detail, provided the double knuckle hinge construction be preserved.
Dated 12th November 1889
WM. JORDAN,
120, Chancery Lane, W.C., Agent for the Applicants.
COMPLETE SPECIFICATION.
() A New or Improved Hinged Expansion-gear for Bridges, Piers,
Girder-work, Roofing, and such like Purposes.
We CHARLES JOHN WESTWOOD and HARRY RIGBY, Civil Engineers, both of Napier
Yard, Millwall in the County of Middlesex, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly described
5 and ascertained in and by the following statement :-
This invention relates to certain new or improved hinged expansion gear for bridges,
TD 037

page_text: piers, girder-work, roofing and such like purposes the objects being; (1) to prevent
the bearing at the expansion end of the structure from becoming oxidized, silted-up,
concreted or fixed in any way by the action of blown dust, rubbish, oxidation or
chemical action as of the atmosphere or sea-water, or such like foreign or corrosive
matter as is found to be the case, and to take place where roller gear or sliding bed :
and bearing plates are used. (2) To give a perfectly free scope for expansion or
contraction to the structure; and, (3) to reduce the cost in material, fitting, and for
repairs as compared with the generally accepted roller gear, or sliding plates and
reducing the bearing or machined surfaces to about one fourth of the usual area.
In carrying out the invention there is to be omployed a hinged or articulated bearing 1
consisting of plates with intermediato block or link piece or pieces, as will hereinafter
more particularly be described. These plates and block or link hinged bearings may
be arranged in sets, two or more in line.
In order that this invention may be well understood there is annexed hereto a sheet
of drawings illustrative of the construction and showing how the invention is carried
into practical effect, similar letters of reference being used to indicato like parts in all
the drawings.
Fig. 1, is an elevation partly in section showing construction of the gear or fitting
according to this invention.
Fig. 2, is a side view of the construction shown in Fig. 1.
Fig. 3, is a sectional plan at line A A, of Figs. 1 and 2.
Fig. 4, represents in like view to Fig. 1 a modification of the construction of the
hinge or articulation.
Fig. 5, shows in diagram the gear fitted at the "expansion" end a, of a girder.
a, a¹ are lower and upper sadillo-plates fitted to the double-ended knuckle-block b,
employed and set in between the two saddle-plates so forming what is substantially a
free and double hinge or articulation. The top and bottom bearing surfaces 1, of
the knuckle-block are rounded and machined as also will be the receiving saddles
correspondingly.
In using this improved gear the lower or bed-saddle-plate a, will be fixed to the pier,
abutment or whatever attachment is provided and the upper-saddle-plate a', will be
attached to the main girders of the bridge or such structure and the double
knuckle-block will be disposed between the two oppositely arranged saddle-plate
bearings a, a¹.
Under the effect of expansion or contraction the double knuckle-block b, will then
work forward or backward to the extent necessary and following the variations of
temperature which will affect the structure.
In "setting" this gear in, say, low temperature the knuckle block b will be set with
its central line out of the perpendicular and with the proper inclination of said central
line towards the fixed end of the structuro and in a temperature higher than the normal
one the "setting" will be reversely done, that is with the central line of the knuckle-
block or hinge inclined from the perpendicular away from the fixed end of the structure.
Although this expansion goar and fitting has thus far been described in this
Specification in a certain manner it may be varied in construction, material
employed, or design of detail provided the double-hinge or articulation construction be
preserved.
There is shown in Fig. 4, a modification according to which construction the hinge
piece b, machined at its top and bottom surfaces to receive the machined portions a²,
of the gear plates a, a¹.
Again the hinge piece or pieces b' may be made as a link or links standing between
a lower and upper plate a, a, having bearing surfaces corresponding to the link-pieces,
and having provided sido plates of the capping portions of the plates a, a', and with
the said cap-platos pins or studs may then be provided engaging with or taking into
holes or dwells so forming joints or articulation to or with the intermediate link-piece
or pieces and the capping plates, so that the upper-plato a', may ride above the lower
fixed plate a of the construction according to the expansion or contraction.

page_text: 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 :-
The new or improved hinged expansion gear or fitting for the expansion end of
bridges, piers, girder-work, roofing and such like purposes having the hinge piece or
pieces b, standing between the top and the bottom plates a¹, a, constructed and
operating as and for the purpose herein set forth.
Dated at Tel 1900
For C. J. WESTWOOD,
and
H. RIGBY.
Walter A. Barlow,
45, Chancery Lane, London, W.C.
For C. J. WESTWOOD,
and
H. RIGBY.
Walter A. Barlow,
6, Chancery Lane, London, W.C.