Improvements in or relating to Bag and other Chutes for Warehouses, Mills, Elevators, and the like.
Year: 1899

page_text: Date of Application, 14th June, 1899
Complete Specification Left, 10th Mar., 1900-Accepted, 14th Apr., 1900
PROVISIONAL SPECIFICATION.
Improvements in or relating to Bag and other Chutes for Warehouses,
Mills, Elevators, and the like.
I, WILLIAM ALLEN VERNON, of the Atlantic, Brunswick Street, in the City
of Liverpool, Flour Miller, do hereby declare the nature of this invention
to be as follows:
The coefficient of friction of bags of various kinds of material and of different
material of bags differ very widely; thus jute bags differ considerably from
canvas bags and the same is the case with cotton bags, and a bag of bran will
slide down with very much less friction than a bag of shorts, or even most
kinds of flour. Consequently a slope that will deliver a bag of shorts at the
most desirable speed will allow a bag of bran to descend with a very dangerous
velocity. In order therefore to prevent too great velocity in these bags I have
designed a brake formed of a board sloping at a very acute angle with the bag
chute and an arrangement of weights whereby different pressure can be brought
on this board for each different kind of bag and thus the impetus of the bag
taken away by its friction between the checking board and the bag chute. The
arrangement of weights however in my experimental device involves a very
considerable amount of labour as a heavy board ten or twelve feet long had to
be lifted and the weights regulated in the case of each change of bag. In
order to overcome this objection I propose instead of weights to construct an
abutment some distance above the chute and strongly braced to it, against
which a cylinder and piston works, the cylinder being fixed to the abutment
and the piston rod projecting from the piston towards the chute. The end of
the piston rod is attached to the lower end of the friction board. The upper
end of the cylinder is provided with a valve opening inwards; also from near
the top of the piston to a short distance from the bottom is a port supplied
with a tap or valve. It does not go right to the bottom as it is desirable that
there should be an air cushion under the piston. Round the tap handle I place
a scale on which is marked the exact position as found by practice for each
variety of bag and material.
The mode of action is as follows:.
The tap being partially open the piston, piston rod and the end of the bag
check fall by gravity till they come in contact with the chute or with a stop.
As a bag comes down it slides between the chute and the bag check board
forcing the latter up. If the tap be wide open very little force is sufficient to
lift the bag check board sufficient for the bag to pass through. If however the
cock be partially closed or very much throttled, very much greater resistance
is caused as the air can only slowly pass up from above the piston to below it,
and consequently a strong air cushion only gradually neutralized is formed
above the piston. By therefore regulating the valve cock any required resist-
ance can be placed against the rising of the bag check board. The moment
however the bag has passed there is no resistance to the descent of the bag

page_text: check board as air is freely admitted above through the upper valve and the air
rapidly passes from below the piston to above the piston or through an escape
valve if necessary and consequently the bag check board at once goes into the
proper position to receive the next bag. As bags of shorts and other bags
having a high coefficient of friction do not require the bag check board at all
I arrange a stop so that the bag check board can be hooked up sufficiently
high when required for a bag to pass underneath it without touching it.
These chutes are applicable not merely to the chutes in mills and warehouses,
but to those in elevators and on dock quays for the holds of ships and
the like, and the apparatus is of course applicable to other packages besides
ordinary bags or can be made applicable by very slight modification to suit the
particular kind of package or goods in a way that would not require invention.
Dated the 13th day of June 1899.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
Improvements in or relating to Bag and other Chutes for Warehouses,
Mills, Elevators, and the like.
I, WILLIAM ALLEN VERNON, of the Atlantic, Brunswick Street, in the City
of Liverpool, Flour Miller, 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:-
―
The coefficient of friction of bags of various kinds of material and also bags
made of the same material but containing different kinds of goods, differs very
widely. Thus, jute bags differ very considerably from canvas bags, and the
same is the case with cotton bags, and a bag of bran will slide down with very
much less friction than a bag of shorts, or even most kinds of flour, conse-
quently a slope that will deliver a bag of shorts at a most desirable speed will
allow a bag of bran to descend with a very dangerous velocity. The same thing
applies with similar bags descending longer or shorter distances. In order
therefore to prevent too great a velocity in these bags, I have designed this
invention, which is best described by aid of the accompanying drawings, in
which,
Figure 1 is a front elevation partly in section of my apparatus taken at right
angles to the axis of the shute."
Figure 2 a side elevation of the same.
In these is the shute formed usually of timber, B a check board such as
is used at the present time. One end of my check board is hinged at a suffi-
cient distance from the shute to insure the bag passing freely under the hinged
end, while the other end or a part of the board a short distance from the end
is hinged by a connecting rod to the piston of a compressed air cylinder. In
the drawings, CC are connecting rods, D the piston rod, and E the cylinder.
FF are a couple of weighted or spring valves freely admitting air into the
cylinder, but not allowing its exit. GG are two stop valves allowing a limited
adjustable exit of air, the adjustment being effected by the hand wheels HH.
Round the top tap handle may be placed if desired a scale, on which can be
aarked the exact position as found by practice for each variety of bag.
The mode of action is as follows:-
The check board connecting rods and pistons being of considerable weight

page_text: the piston naturally descends to the lowest point, consequently the check nor-
mally is always at its nearest distance to the shute. When a bag comes down,
its thickness being greater than the distance between the shute and the check
board A it forces up the piston against the pressure of the air in the cylinder E
which can only slowly escape through the upper valve G. Thus the bag is
checked. The moment the bag passes, the compression of the air in the
cylinder E forces the piston down again but not with a bang, but only gradu-
ally, as the air which had previously entered through the lower valve F can
only slowly escape through the valve G. The air thus forms a buffer to prevent
a sudden jerk after the bag has passed. In the meantime air enters at the
upper valve F to replace the air which has previously escaped through the upper
valve G. The check is consequently at its normal position when the next bag
descends, and the cycle of operations is renewed.
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
1 claim is:-
1. The improvement in bag or other shutes for warehouses, mills, elevators,
and the like, which consists in an elastic or hinged check board arranged nor-
mally at an angle with the shute and its end at a less distance from the shute
than the diameter of the bag or sack, and an air cushioning device operating
said check whereby a sufficient gradual resistance is brought to bear on each
bag passing through the shute (to ensure its easy handling on delivery regard-
less of its previous velocity).
2. In air cushioning devices for bag or other shutes for warehouses, mills,
elevators or the like, the arrangement for securing a limited adjustable exit of
air from the cylinder, so as to vary the resistance automatically substantially
as described.
Dated this oh day of March
WM. P. THOMPSON & Co.,
Patent Agents of Liverpool, Manchester, Birmingham and London.