IMPROVEMENTS IN OR ADDITIONS TO POLES FOR LAWN TENNIS NETS
Year: 1885

page_text: I, FREDERICK ST BARBE SLADEN, of Leighton Hall, Ironbridge, Shropshire,
Gentleman, do hereby declare the nature of my invention for "IMPROVEMENTS
IN OR ADDITIONS TO POLES FOR LAWN TENNIS NETS" and in what manner the
same is to be performed, to be particularly described and ascertained in and by.
the following statement, reference being had to the accompanying drawings and to
the letters and Figures marked thereon, that is to say :-
My Invention relates to improvements in or additions to poles for lawn tennis
nets and the objects of my Invention are first, to provide an improved means
whereby an uniform tension will be maintained on the line on which the top of the
net is threaded or otherwise attached so as to retain it tightly at a proper height
under varying conditions; second, to provide means for quickly releasing the
tension on the said line as is required when removing the poles; third, to provide
sockets for the lower ends of the poles which will enable the poles to maintain
their upright position and to be readily removed from the ground and readily
refixed.
I proceed with reference to the accompanying drawings to fully describe my
Invention.
Similar letters refer to similar parts throughout the several Figures.
Fig. 1 is a front elevation partly in section of a lawn tennis pole constructed in
accordance with my Invention; Fig. 2. is a side elevation, Fig. 2* a part side
elevation and Fig. 3 a plan of the same; Fig. 4 shews separately the cap for the
same in elevation and section; Fig. 5 shews detailed views of a two sheaved
pulley block for the same and Fig. 6 is a general view of the net and poles
complete.
For the purposes of my Invention I provide a tubular pole A, preferably of
wrought iron or other suitable metal, having a cap B attached thereto, preferably
by means of a set screw b¹. Within the said cap B are any convenient number of
grooved pulleys C, or a single pulley may be used, free to revolve on or with the
axis c. The pulley block D is formed (preferably with a hook d') for attachment
to the line E on which the top of the net is threaded or otherwise attached and is
provided with any convenient number of sheaves F free to revolve on the pin f¹,
or a single sheave may be used. One end of a metallic or other cord G is attached
to the cap or pole (preferably to the set screw b³) or it may be attached to the

page_text: pulley block D, and the cord is lead round the sheaves F and C and the other end
is attached to a suitable counterweight H free to move up and down inside the
pole A. The counterweight H is made heavy enough with the assistance of the
multiplying pulleys C and F to maintain an uniform tension on the line E and to
retain it tightly at a proper height under varying conditions.
In order that the tension on the said line E may be quickly released I form with
or attach to the counterweight H a pin h¹ which projects through a slot a¹ in the
post A the top a² of which is produced sideways and downwards. The counter-
weight can be raised by the pin ' to quickly release the tension on the line and
the weight can be maintained at the top of the pole by turning the pin to lodge in
the top part a² of the slot, as shewn in Fig. 2°.
In order that lawn tennis poles may be readily removed and refixed I provide for
each pole a socket K, preferably of cast iron, in which the pole fits easily. The
sockets are buried in the ground as shewn in Fig. 6 and to the sides of each I form
or attach wings or plates which by exposing a large surface to the ground
maintain the poles upright as they cannot be strained out of their perpendicular
position by the pull on the net.
I wish it to be understood that I do not limit myself to the precise details as
herein described and illustrated as the same may be varied without departing from
- the nature of my Invention.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. In poles for lawn tennis nets the application and use of an internal counter-
weight for maintaining a constant tension on the line at the top of the net as herein
set forth.
2. In poles for lawn tennis nets the combination of an internal counterweight
with multiplying pulleys arranged to operate substantially as and for the purposes
herein set forth and illustrated.
3. In poles for lawn tennis nets having internal counterweights the projecting
pin h or other equivalent means for lifting the counterweight in combination with
a bayonet slot a² or other equivalent means for maintaining it at the top of the
pole as herein set forth and illustrated.
4. A socket for a lawn tennis pole having side wings or plates as and for the
purpose herein set forth.