IMPROVEMENTS IN SAND PUMPS, OR APPARATUS FOR EXCAVATING SAND AND OTHER MATERIAL UNDER WATER
Year: 1874

page_text: LETTERS PATENT to Howard John Kennard, of No. 67, Upper Thames
Street, in the City of London, for the Invention of "IMPROVEMENTS
PROVISIONAL SPECIFICATION left by the said Howard John Kennard
at the Office of the Commissioners of Patents, with his Petition.
on the 22nd May 1874.
I, HOWARD JOHN KENNARD, of No. 67, Upper Thames Street, in the
City of London, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN SAND PUMPS, OR APPARATUS FOR EXCAVATING SAND AND OTHER
MATERIAL UNDER WATER," to be as follows:-
on the 22nd May 1874.
I, HOWARD JOHN KENNARD, of No. 67, Upper Thames Street, in the
City of London, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN SAND PUMPS, OR APPARATUS FOR EXCAVATING SAND AND OTHER
MATERIAL UNDER WATER," to be as follows:-

page_text: :
According to one of my present improvements instead of forming
flanges or stops in the cylinder in which the piston works for the purpose
of limiting the stroke of the piston, I fix at the upper end of the cylinder
a bridge piece having a hole through which the piston rod passes, against
which bridge piece the piston, or a caoutchouc cushion upon the same
bears at the end of the up stroke, while the piston rod is provided at its
outer end with a collar which bears against the top of the bridge piece
or against a caoutchouc cushion upon the same at the end of the down
stroke. The bridge piece may conveniently be fixed to the cylinder by
providing the latter with external lugs which are grasped by hooked
ends on the bridge piece, a metal ring being shrunk on over these
looked ends so as to hold the bridge piece securely in position.
Another improvement has for its object to insure a water-tight joint
between the removeable bottom of the apparatus and the flange of the
box to which it is fixed. For this purpose I form in the face of such
flange a circular groove into which is fitted a caoutchouc ring so as to
project somewhat beyond the flange, so that when the removeable
bottom is secured in place it presses against such caoutchouc ring and
thus forms a water-tight joint.
Another improvement relates to the means of imparting motion to the
piston of the apparatus. This is at present effected by attaching to the
piston rod a rope or chain, which is passed over an overhead pulley, its
free end being pulled down by hand in order to raise the piston in the
cylinder, while the down stroke of the piston is effected by its weight.
According to my present improvement I attach to the free end of the
said rope or chain a weight of sucli a size as to ensure that by its descent
it will draw up the piston with sufficient rapidity to the full extent of
its stroke. This weight is raised by hand or by any suitable known
contrivance in order to allow the piston to perform its down stroke, and
is then allowed to fall in order to cause the piston to perform its up
stroke.
Another improvement relates to a modified construction and arrange-
ment of the said apparatus more particularly adapted for excavating the
sand or other material from within cylinders or tubular piles for piers
or foundations to be sunk under water. For this purpose I place
outside such cylinders or tubular piles, at a convenient distance from
the same, a cylinder containing a piston, and provided at its lower open

page_text: end with a hinged flap that closes in a water-tight manner against the
end surface of the cylinder, a caoutchouc ring being for this purpose
inserted in a groove in a flange on the end of the cylinder, against which
ring the flap presses when closed. From near the lower end of the
cylinder a flexible or jointed pipe leads into the pier cylinder to be sunk.
The pipe is passed either through a hole in the side of the pier cylinder
or through the upper open end of the same, and is led down to the
surface of the earth inside the cylinder where it is attached to a nozzle
or tube that penetrates somewhat into the ground.`
The before-mentioned cylinder of the sand pump is supported by barges
or by a scaffolding, so that its lower end is immersed somewhat below
the surface of the water. Its lower end being closed by the flap the
piston is drawn upwards, whereby the water, together with the sand or
other loose material, is drawn from the bottom of the pier cylinder into
the pump cylinder, and on the descent of the piston the flap opens and
the water and sand are discharged from the pump. The flap may either
be provided with a balance weight, so that it will close of itself, or it
may be pulled up into the closed position by means of a rope or chain
attached thereto. The piston is made to work casily in the pump, and
to insure the proper suction during the up. stroke a small quantity of
water is caused to flow into the pump above the piston so as to prevent
the ingress of air.
:
The pump cylinder may be made of large dimensions, and may be
arranged to excavate the sand simultaneously from within two or more
pier cylinders by providing it with two or more of the before-mentioned
flexible or jointed pipes, each leading into one of the cylinders.
Although I have described the above modified form of the, apparatus.
as principally applicable to excavating sand or other material from
within pier cylinders, yet it may also be applied with advantage for
excavating or dredging material from the bed of a river or other water,
the before-mentioned flexible or jointed pipe being led down to the bed
and there connected to a nozzle or tube penetrating somewhat into the
ground.
"
Also, instead of placing the cylinder of the sand pump with its lower
end immersed in the water as described, it may be arranged with its
lower end inside a barge so as to discharge the material excavated into
the barge and the lower end may either be immersed in the water in

page_text: the barge, or it may be above the level of the water, the hinged flap,
being made to fit in a sufficiently air-tight manner against the end of the
pump cylinder to insure a proper suction.
SPECIFICATION in pursuance of the conditions of the Letters Patent,.
filed by the said Howard John Kennard in the Great Scal Patent
Office on the 4th November 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HOWARD
JOHN KENNARD, of No. 67, Upper Thames Street, in the City of
London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of May, in the year
of our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Howard John Kennard, Her special
license, that I, the said Howard John Kennard, my executors, adminis-
trators, and assigns, or such others as I, the said Howard John Kennard,
my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN SAND PUMPS, OR APPARATUS FOR EXCAVATING SAND AND
OTHER MATERIAL UNDER WATER," upon the condition (amongst others) that
'I, the said Howard John Kennard, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and scals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Howard John Kennard, de hereby
declare the nature of the said Invention, and in what manner the same

page_text: by the following statement thereof, reference being mad to the accom-
panying Sheet of Drawings, and to the figures and letters marked
thereon, that is to say :-
My Invention relates to apparatus for excavating sand and gravel'
under water, now generally known as "sand pumps," for which Letters
Patent were granted to me on the 15th June 1861, No. 1534.
According to one of my present improvements instead of forming
flanges or stops in the cylinder in which the piston works for the purpose
of limiting the stroke of the piston, I fix at the upper end of the cylinder
a bridge piece having a hole through which the piston rod. passes,
against which bridge picce the piston, or a caoutchouc cushion upon the
same, bears at the end of the up stroke, while the piston rod is provided
at its outer end with a collar which bears against the top of the bridge
piece or against a caoutchouc cushion upon the same at the end of the
down stroke. The bridge piece may conveniently be fixed to the
cylinder by providing the latter with external lugs which are grasped
by hooked ends on the bridge piece, a metal ring being shrunk on.
over these hooked ends so as to hold the bridge piece securely in
position.
Another improvement has for its object to insure a water-tight joint
between the removeable bottom of the apparatus and the flange of the
box to which it is fixed. For this purpose I form in the face of sucli
flange a circular groove into which is fitted a caoutchouc ring so as to
project somewhat beyond the flange, so that when the removeable
bottom is secured in place it presses against such caoutchouc ring and
thus forms a water-tight joint.
Fig. 1 represents a vertical section, and Fig. 1ª a sectional plan of a
sand pump embodying these improvements.
A is the bridge piece having hooked ends a, a, engaging under a
collar or a pair of lugs projecting from the cylindrical body of the pump,
and being secured by a ring B shrunk on a caoutchouc cushion or other
suitable clastic buffer C on the piston stops against the bridge piece A
at the upstroke of the piston, and a similar buffer D on the bridge piece
stops the collar E on the piston rod at the down stroke.
Fig. 2 represents to an enlarged scale a section of part of the joint
at the bottom edge F of the sand box made tight by a caoutchouc ring f

page_text: inserted into a circular groove formed in the angle iron ring of the box,
which is squeezed by the bottom plate when the box is closed. The said
groove is made somewhat deeper than a semicircle, as shewn, so that tho
caoutchouc ring f (the section of which is slightly larger in diameter
than the groove) when squeezed into the groove will be firmly held
therein.
Another improvement relates to the means of imparting motion to
the piston of the apparatus. This is at present effected by attaching to
the piston rod a rope or chain, which is passed over an overhead
pulley, its free end being pulled down by hand in order to raise the
piston in the cylinder, while the down stroke of the piston is effected by
its weight.
· According to my present improvement I attach to the free end of the
said rope or chain a weight of such a size as to insure that by its descent
it will draw up the piston with sufficient rapidity to the full extent of
its stroke. The weight is raised by hand or by any suitable known
contrivance in order to allow the piston to perform its down stroke, and
is then allowed to fall in order to cause the piston to perform its up
stroke.
Another improvement relates to a modified construction and arrange-
ment of the said apparatus more particularly adapted for excavating the
sand or other material from within cylinders or tubular piles for piers or
foundations to be sunk under water. For this purpose I place outside
such cylinders or tubular piles, at a convenient distance from the same,
a cylinder containing a piston and provided at its lower open end with a
hinged flap that closes in a water-tight manner against the end surface
of the cylinder, a caoutchouc ring being for this purpose inserted in a
groove in a flange on the end of a cylinder, against which ring the flap
presses when closed. From near the lower end of the cylinder a flexible
or jointed pipe leads into the pier cylinder to be sunk. The pipe is
passed either through a hole in the side of the pier cylinder or through
the upper open end of the same, and is led down to the surface of the
.earth inside the cylinder where it is attached to a nozzle or tube that
penetrates somewhat into the ground.
Fig. 3 represents a vertical section of a sand pump arranged as
described above for clearing material out of a pier cylinder or tubular
"nile'
To this ase the bottom of the ñumn is covered by a flan' G the

page_text: joint being made tight by a caoutchouc ring; as described above. The
suction pipe of the pump is connected by a flexible or jointed tube H to
the nozzle K, which is inserted into the material to be operated on. The
flap G may be counterweighted to close automatically, as shewn at L,
Fig. 3, or it may be pulled up by the rope or chain M.
The before-mentioned cylinder of the sand pump is supported by.
barges or by a scaffolding, so that its lower end is immersed somewhat
below the surface of the water. Its lower end being closed by the flap
the piston is drawn upwards, whereby the water, together with the sand
or other loose material, is drawn from the bottom of the pier cylinder
into the pump cylinder, and on the descent of the piston the flap opens
and the water and sand are discharged from the pump. The piston is
made to work easily in the pump, and to insure the proper suction
during the up stroke a small quantity of water is caused to flow into the
pump above the piston so as to prevent the ingress of air.
The pump cylinder may be made of large dimensions, and may be
arranged to excavate the sand simultaneously from within two or more
pier cylinders by providing it with two or more of the before-mentioned
flexible or jointed pipes, each leading into one of the cylinders.
Although I have described the above modified form of the apparatus
as principally applicable to excavating sand or other material from
within pier cylinders, yet it may also be applied with advantage for
excavating or dredging material from the bed of a river or other water,
the before-mentioned flexible or jointed pipe being led down to the bed
and there connected to a nozzle or tube penetrating somewhat into the
ground.
Also, instead of placing the cylinder of the sand pump with its lower
end immersed in the water as described, it may be arranged with its
lower end inside a barge so as to discharge the material excavated into
the barge, and the lower end may either be immersed in the water in
the barge, or it may be above the level of the water, the hinged flap
being made to fit in a sufficiently air-tight manner against the end of the
pump cylinder to insure a proper suction.
Having thus described the nature of my Invention and in what
manner the same is to be performed, I claim,-
First. The use, for sand pumps, of a bridge piece with buffers to stop
the piston at each end of its stroke, substantially as herein described.

page_text: Second. Forming the joint at the bottom of a sand pump or of the
sand box of such a pump.by-means of a caoutchouc ring, substantially as
herein described.
Third. Working sand pumps by arranging a descending weight to
raise the piston for its up stroke, the said weight being raised to permit
the piston to effect its down stroke.
Fourth. Constructing a sand pump with a hinged flap bottom to
operate with a flexible or jointed tube and nozzle, substantially in the
manner and for the purposes herein set forth.
In witness whereof, I, the said Howard John Kennard, have here- 1
unto set my hand and seal, this Second day of November, in
the year of our Lord One thousand eight hundred and seventy-
four.
HOWARD JOHN KENNARD. (L.S.)