Year: 1889

page_text: I DANIEL SMITH SINCLAIR of 54 Gordon Street Glasgow in the county of Lanark,
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention is especially applicable to poles for the game of Lawn Tennis and
fittings for such poles.
The object is to provide a simple and easy way of attaching and straining the
cord, whether it be metallic or of other material, which supports the net used in
playing the game: to have a provision for bringing the net to the full height in
case of the cord being other than the right length and further to have a method
of fastening the cord that shall not destroy its end.
The pole may be of wood or other material of any suitable cross section and it
may be fixed in a socket or resting on the ground & supported by guy ropes, or the
end of the pole itself may be sunk in the ground to a sufficient depth to keep it firm.
The straining device consists of a simple lever capable of partial rotation in a
vertical plane on a pivot or pin. The cord supporting the net runs over a pulley
at the required height on the pole and is fastened to this lever in such a way and at
such a point that the forcing up or down, as the case may be, of the lever-end shall
shorten the length of the cord between the poles and so bring up the net.
I prefer to have the lever turn in a vertical plane but the same device may be applied
with a lever working in a horizontal plane.
To fix the lever when the straining has been accomplished I prefer to have the
free end thereof provided with a hook to engage a ring on the pole or a ring to engage a
hook. I also use an automatic locking arrangement consisting of a spring catch
engage a detent on the pole but I do not bind myself to any particular method of
fastening.
to
To provide for a varying length of supporting cord I attach to its end a short
piece of chain and in straining up a hook on the lever described is inserted into
such a link as will pull the cord to the required height when the lever is forced
home.
In place of the chain I also make on the cord itself or attach to it a series of loops
or knots and a suitable hook on the lever to engage with them.
Dated this Seventh day of Tune 1000
D. S. SINCLAIR,
Applicant.
Fittings for Lawn Tennis Poles.
I DANIEL SMITH SINCLAIR of 54 Gordon Street Glasgow in the county of Lanark,
Engineer 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 relates to poles for lawn tennis nets and to fittings therefor and
consists chiefly in the apparatus for straining-up and regulating the tension of the
net-supporting cord. The pole herein described is so constructed and operated that in
all respects it conforms to the laws of the game of lawn tennis as at present in force
but these laws do not affect the claim of novelty for the pole.
The general method of construction of the pole will appear from the accompanying
drawing which shows poles suitable for insertion into sockets commonly used for ash
courts but the bottom part may be modified to suit other circumstances without
prejudice to my claimed pole.

page_text: Referring to the drawing the pole A A¹ is made of wrought iron such as gas-tube of
suitable size and has fixed to the top a cast iron head containing a pulley over which
runs the supporting cord. "B" is a pole of tubular cast iron and shows a modified
form of the lever but is operated in precisely in the same way as the other. "C" is
a wooden pole and may have the metal fittings fastened on by woodscrews.
The same letters of reference indicate similar or corresponding parts in all the cases.
(a) is a lever preferably of wrought-iron turning about a pin at (b) and having at (4) a
hook engaged the open end of which may be inserted into the links of the chain ().
At (e) is a hook riveted screwed. or otherwise fastened over which may be passed a
ring carried by the lever-end.
".
The method of straining-up the net & fixing it in position is as follows:-the lever
end is disengaged from the hook (e) and held free until the hook at (c) is inserted
into a supposed suitable link of the chain (d); the end of the net-supporting cord (g)
having previously been attached to the hook (h). The lever is then pressed home and
in so doing the cord & net will be pulled up." If the latter he not then high enough
the lever is again released and by shifting the hook at (e) so as to shorten the length of
chain between (e) and (4) the net may be pulled to the required height...
If on pressing the lever home too great a stress is put upon the cord the hook
at (c) is transferred to another link so as to give more active chain.
Thus it will be easily understood that by the adaptability of the fittings, a cord
longer or shorter than the proper length can be used. I also make on the cord itself
a series of loops or knots to engage with the hook (4) and act in the same manner as
the chain in increasing the range of applicability of the apparatus..
The loose part of the chain below (c) takes no part in the operation but is necessary
in case of a shorter supporting cord.
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
"
I. A lawn-tennis pole having fittings substantially as described.
II. The application to lawn-tennis poles of the lever and chain operated in the
manner and for the purpose described.
III. The combination of lever, chain and other necessary parts for producing an
adjustable stress substantially in the manner described.
Dated this Sixth day of March 1890.