Improvements in Chains for Transmitting Motive Power.
Year: 1886

page_text: Date of Application, 14th Dec., 1886.
Complete Left, 5th May, 1887.
Complete Accepted, 17th June, 1887.
PROVISIONAL SPECIFICATION.
Improvements in Chains for Transmitting Motive Power.
We JAMES RICHARD TRIGWELL and ALFRED HENRY TRIGWELL of 146 Brixton
Hill in the County of Surrey, Engineers, do hereby declare the nature of this invention
to be as follows:-
The object of our invention is to compensate for the wear of metal in the links and
rivits of pitch chains so as to keep the spaces or openings in such chains at equal
distances apart so as to agree with the pitch of the chain wheel. For this purpose the
links which form the opening for the teeth of the wheel are connected by means of
a C spring the adjacent edges of which are connected by a screw by means of which
they may be drawn nearer together as the rivits or links wear away. The spring is
thickened on each side so as to afford sufficient bearing metal for the rivits. Instead
of C springs being used the links may be connected by lugs coupled by screws on
each side.
J. R. TRIGWELL.
A. H. TRIGWELL.

page_text: COMPLETE SPECIFICATION.
Improvements in Chains for Transmitting Motive Power.
We, JAMES RICHARD TRIGWELL and ALFRED HENRY TRIGWELL, of 146 Brixton
Hill, in the County of Surrey, Engineers do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The objection of our invention is to compensate for the wear of metal in the links
and rivets of pitch chains, so as to keep the spaces or openings in such chains at
equal distances apart in order to agree with the pitch of the chain wheel.
For this purpose the links, which form the opening for the teeth of the wheel, are
connected by means of a C spring, the edges of which are connected by a screw so
that they may be drawn nearer together as the rivets or links wear away. The
links may also be connected by double screw rods screwed into lugs on each side of the
links.
By the use of our method the ends of the adjacent links are brought into contact
when the chain is in true pitch, and when there is a space visible between the ends of
any two adjacent links it is a sign that the two links must be screwed up.
In order to show more clearly how our invention is carried out we furnish drawings
in which similar letters represent corresponding parts throughout.
Fig. 1 is a representation of two links joined by a C spring.
Fig. 2 is the spring used in Fig. 1 shown separately.
Fig. 4 is a C spring in the shape of a split bowl with link attached.
Fig. 3 is another form of C spring.
Fig. 5 is another form of C spring.
Fig. 6 is a representation of two links connected together by double screw pieces
screwed on to lugs on each side of the links.
Fig. 7 is a lug with male screw.
Fig. 8 is a double screw piece with female threads.
A is a link.
B is a head of cross piece put through orifices at end of link.
Dorifice at end of link.
E the C spring.
G the screw pulling together the ends of C spring.
H aperture through C spring.
J lug.
K double screw connecting piece.
In the mothed chain D
1

page_text: Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed, we declare that what we claim is:
1st. A method of compensating the wear of metal in the links and rivets of pitch
chains by coupling them together by a C spring substantially as described.
2nd. The form of C spring shown in Fig. 2 for the purpose described.
3rd. The form of C spring shown in Fig. 3 for the purpose described.
4th. The form of C spring shown in Fig. 4 for the purpose described.
5th. The form of C spring shown in Fig. 5 for the purpose described.
6th. A method of compensating the wear of metal in the links and rivets of pitch
chains by coupling them together by lugs and double screw pieces substantially as
described.