Improvements in Driving Bands or Belts.
Year: 1895

page_text: Date of Application, 7th Nov., 1895
Complete Specification Left, 7th Sept., 1896-Accepted, 7th Nov., 1898
Improvements in Driving Bands or Belts.
I, ANTHONY PULBROOK of 8 Unwin Mansions, Queen's Club Gardens, West
Kensington, in the County of Middlesex, Solicitor, do hereby declare the nature
of this invention to be as follows:-
:
Heretofore, so far as I am a vare, driving bands or belts have been made solid,
but according to my present improvements I make them bollow, and I fill the
hollow space with air, gas, or other compressible fluid, or with water or other more
or less incompressible fluid at or above atmospheric pressure. I make the belting
of leather, india rubber insertion, or other suitable flexible airtight material prefer-
ably as non-stretchable as possible, and of a cross section such as will adapt itself
best, when its hollow interior is charged with the air or other fluid, to the circum-
ference of the pulley over which it works. For example, for a flat faced drum the
section may be that of a flat tube, for a pulley rounded on the face the section may
he that of a crescent shaped tube with the hollow curve in contact with the pulley,
or for a grooved pulley the section may be that of a tube adapted to fit the groove
more or less.
The hollow airtight space in the band or belt may be divided into any number
of separate airtight spaces by longitudinal or transverse divisions, and the band or
belt may be strengthened by strips of any suitable material cemented or otherwise
suitably attached to the inside or outside of the band or belt, and may pass from
the upper to the lower side, so that both sides may be made to bear their due
proportion of the strain.
The band or belt may be provided with a charging and non-return valve through
which the air or other fluid can be charged into the hollow space in a manner
similar to that employed for inflating cycle tyres, and any suitable arrangements
may be provided for fastening the ends together, and for taking up the slack when
the band or belt stretches.
Bands or belts made in accordance with my invention apply themselves more
closely, and therefore adhere better to the pulleys than the ordinary solid belt of
leather, indiarubber insertion, cotton webbing, and such like, and are much more
durable.
Dated this 6th day of November 1895.
Improvements in Driving Bands or Belts.
I, ANTHONY PULBROOK, of 8 Unwin Mansions, Queen's Club Gardens, West
Kensington, in the County of Middlesex, Solicitor, 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:
Heretofore, so far as I am aware, driving bands or belts have been made solid;

page_text: but according to my present improvements I make them hollow, and I fill the
hollow space with air, gas, or other compressible fluid, or with water or other
more or less incompressible fluid at or above atmospheric pressure.
And in order that the invention may be fully understood I will now proceed to
describe the same with the aid of the accompanying sheet of drawings.
I make the belting of leather, india rubber insertion, or other suitable flexible
airtight material, preferably as non-stretchable as possible, and of a cross section
such as will adapt itself best, when the hollow interior is charged with the air or
other fluid, to the circumference of the pulley over which it works. For example,
for a flat faced drum or pulley the section may be that of a flat tube as shown in
Figure 1 of the drawing, the part A coming next to the drum or pulley; for a
pulley rounded on the face, the section may be that of a crescent shaped tube, as
shown in Figure 2, with the hollow curved part A' in contact with the pulley; or
for a grooved pulley the section may be that of a tube, as shown in Figure 3,
adapted to fit into the groove more or less accurately.
The hollow airtight space in the band or belt may be divided into any number
of separate airtight spaces by longitudinal or traverse partitions or divisions, as
shown, by way of example, by dotted lines at B, B, in Figure 1; and the band or
belt may be strengthened by strips of any suitable material cemented or otherwise
suitably attached to the inside of the band or belt, and passing from the upper to
the lower inner sides, as seen at C, C, in the longitudinal section of a hollow band
or belt shown in Figure 4, so that both sides D and E may be made to bear their
due proportion of the strain.
The band or belt may be provided with a charging and non-return valve, not
shown in the drawing, through which the air or other fluid can be charged into the
hollow space in a manner similar to that employed for inflating cycle tyres; and
when the said hollow space is divided into separate airtight compartments or sub-
divisions, as illustrated by the dotted lines in Figure 1, each compartment or
subdivision may be provided with such a charging and non-return valve. It will
be understood that when a charging and non-return valve is provided it must be
placed on the outside of the band or belt or at the side thereof, in order that it may
not come in contact with the pulley when it passes round the latter.
The ends of the band or belt may be fastened together by cement or in any
other suitable way that will make it into an endless airtight tube.
'
Suitable arrangements may be provided for taking up the slack when the band
or belt stretches, for example, a band of thin flexible metal F, a flat wire rope; a
chain, or other similar non-stretchable device, may be inserted between the
layers G G of material forming one side of the band or belt, as shown in Figure 5,
the ends of the said band being caused to overlap as shown. Near the said ends
are secured projecting lugs H H¹, see Figure 6, through which pass screws. I
turning freely in the lugs H, but tapped into the lugs H. By turning these screws
the strap F may be tightened up or slackened, and with it the material G G of the
inner or outer side of the hollow band or belt. The tightening up of the band or
belt may also be effected by means of flexible wires or wire cords J run through
eyelets K fixed at intervals at the sides of the band or belt, see Figure 7, the
said wires being tightened up by means of screw couplings or other suitable
devices.
The outer part of the band or belt, that is to say, the part furthest away from
the pulley, may be made of thin sheet metal, wire-rope, chain, or other similar
flexible non-stretchable material inserted between layers of the indiarubber insertion
or other airtight material of which the general body of the band or belt is composed.
My object in having the non-stretchable material in the outer part of the band or
belt is to prevent stretch of the inner part, the pressure of the air in the interior
preventing the stretch of the inner circumference by pressing it against the pulley,
the outer rigid or non-stretchable part serving as a resistance or abutment for the
pressure to react against.
I sometimes arrange the tightening wires outside the pulley as illustrated in

page_text: Figure 8, in which L represents a pulley with a rounded face having a hollow band
or belt M of crescent-like section similar to that shown in Figure 2, but provided
with eyelets K placed at intervals along the edges of the band or belt, and through
which are passed the tightening wires J, wire-ropes, chains, or other flexible nou-
stretchable straining devices, similar to those shown in Figure 7, but in this case
passing at the sides of the pulley L instead of outside the circumference thereof.
I sometimes make the band or belt of two or more tubes placed one within the-
other, as shown by way of example in Figure 9, each tube being provided with
a separate charging and non-return valve for the insertion of Huid into each
tube.
The object of this arrangement is that in the event of an outer tube becoming-
punctured, so that the fluid escapes from it, the next inner tube keeps the band or
belt distended till the outer casing can be repaired.
Instead of passing the tightening wires, cords, or chains through eyelets, as shown
in Figures 7 and 8, they may be enclosed in hems or tubes formed along the sides.
out of the flexible material of which the bands or belts are composed or otherwise,
the ends of the wires, cords, or chains being however left free for the attachment.
of the tightening-up devices.
Bands or belts made in accordance with my invention apply themselves more
closely, and therefore adhere better to the pulleys than the ordinary solid band or
belt of leather, indiarubber insertion, cotton webbing, and such like, and are much
more durable.
Having now particularly described and ascertained the nature of the said inven--
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
:-
Making driving bands or belts with hollow airtight spaces within them, such.
spaces being filled with compressible or non-compressible fluid, substantially as.
described.
Santambar 1806
This 7th
½ day of September 1906.
A. PULBROOK,
Per W. H. Beck,
115 Cannon Street, London, E.C., Agent..