Year: 1887

page_text: Date of Application, 25th Aug., 1887
Complete Left, 24th May, 1888
Complete Accepted, 29th June, 1888
I, JEREMIAH EUGENE MATHEWSON of 265 Upperthorpe, Sheffield, in the County of
York, Engineer do hereby declare the nature of this invention to be as follows:-
My Invention relates to that kind of Sand Blast Apparatus in which the Sand is
propelled by a current of air, such as is, in general use for obscuring and ornamenting
glass.
Heretofore the current of air has been produced by means of pumps or fans driven
continuously by hand or other motive power-the action of the Sand being arrested
when desired (in order to shift or replace the article operated upon) either, 1, by
interposing a shield between the article and the blast pipe, or, 2, by cutting off the
current of air or, 3, by cutting off the supply of Sand. In all of these cases the
power used in driving the pump or fan during such intervals is entirely wasted.
My Invention consists in creating the current of air (either by pressure or by
partial vacuum) intermittently at short convenient intervals, during which the article
operated upon, may be shifted or replaced. The pump or bellows proposed is single
acting, operated by the weight of a man or otherwise, and of such capacity that one
siroke will compress or exhaust a quantity of air sufficient to make at least one distinct
impression or obscuration upon ordinary clear Glass.
When the operation is finished, the current stops, either at the will of the operator,
or by completion of the stroke, and the piston or bellows returns by its own weight or.
otherwise to its former position ready to commence another stroke. During the return
stroke the article may be readjusted or replaced by another.
The pump or bellows may be of such capacity that the air compressed or exhausted
at one stroke will be sufficient to make two or more distinct impressions, the movement
of the piston (operated by a suitable weight or otherwise) being quickly arrested at
any point of the stroke, by merely stopping the current of air by means of a valve
under the control of the operator, or two pumps or bellows working alternately may
be used-making the intervals of intermittence shorter.

page_text: The improvement is particularly applicable to engraving or marking, by manual
labor applied in any convenient way, articles of glass with designs of moderate size
which can be blown on at one operation.
The kind of pump proposed, is made by a cylinder or plunger sliding loosely in
another Cylinder, the joint between them being made by a tube of thin sheet rubber,
or other material impervious to air, folded upon itself-one end of which is secured to
the outer cylinder and the other to the inner cylinder or plunger, making a flexible
bellows like diaphram which is air tight, freo from any sliding friction and from any
wearing action of the Sand.
In case of Machines operated by suction (which is the method proposed) the outer
cylinder forms a settling chamber for the spent Sand.
1, JEREMIAH EUGENE MATHEWSON of 265 Upperthorpe, Sheffield, in the County of
York, 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 :-
My Invention relates to improvements in Sand-blast Apparatus in which the sand
is propelled by a current of air, such as are in general use for obscuring or
ornamenting glass.
Hitherto, the current of air has been produced by means of a fan or pump driven
continuously by hand or other motive power, the action of the sand being arrested
when it is desired to shift or replace the article operated upon either by (1) interposing
a shield between the article and the blast pipe; (2) by cutting off the current of air;
(3) or by cutting off the supply of sand. In each of these methods the power used in
driving the pump or fan during such intervals is entirely wasted.
The effect or result produced by such machines driven by hand power, has been
found to be of comparatively little practical use, on account of the large amount of
friction and leakage, in the exhausting or blowing apparatus.
The first part of my invention relates to a sand blast machine in connection with an
intermittent blowing or exhausting apparatus, the cessations of the blast being
'caused by the completion of the stroke of, a suitable reciprocating blowing or
exhausting apparatus of such dimensions that one stroke will exhaust sufficient air, to
enable at least one distinct impression, or obscuration to be made upon ordinary

page_text: glass. During the cessations of the blast the article under operation is readjusted or
replace: by another.
The second part of my invention relates to the construction of a blowing or exhaust-
ing apparatus for sand blast purposes which consists of a plunger sliding loosely in a
Cylinder, the space between the two being made air-tight by a tube of caouchouc or
other elastic material impervious to air, folded upon itself, one end being secured to
the outer cylinder and the other to the plunger, and constituting a flexible, frictionless
and airtight packing.
And in order clearly to define the invention I annex a sheet of drawings illustrating
an apparatus made according to my invention, and shown chiefly in section.
The apparatus consists of a Cylinder A provided with an outlet valve V¹ and an
inlet vale V2 closed at the bottom, and open at the top, supported on legs B, and
carrying a frame C, provided with one or more pulleys D-A plunger E, of smaller
diameter and about half the length, of the Cylinder A is placed within it, and is drawn
up and let down by means of a rope or chain F, passing over the pulleys D, and down
to the lever G, but if preferred other convenient means of raising and lowering the
plunger E, may be used.
The space between the Cylinder and the plunger is made air-tight by means of a
tube of caouchouc (or other material which is flexible and impervious to air) folded
upon itself, one end being secured to the Cylinder, and the other end secured to the
plunger, either by means of the retaining rings as shown, or by other equivalent
means.
On raising the plunger the caouchouc tube I is "peeled" away from the inner
surface of the Cylinder to which it closely adheres by reason of the pressure of the
outer atmosphere, and deposited upon, or transferred to, the surface of the plunger; on
lowering the plunger this action is reversed.
By the above described arrangement I form an air tight joint free from sliding
friction, and practically free from the wearing action of the sand.
1 connect to one side of the lower part of the Cylinder A, a Sand-blast machine J,
so constructed that the communication between the two, can at any time be opened or
closed by means of a lever K attached to the inlet valve V2, which is retained in its
closed position by a spring, or weight.
The supply of sand is put into a hopper L, and passing down by gravity into the
receptacle M, trickles through a series of small holes and falls upon the plate N, from
which it is carried (by the inrush of air when the valve V2 is opened and the plunger
drawn upwards) up the blast pipe P, it strikes the article placed at Q, through an
opening in the plate over which the article is held and which opening it practically
closes.
The spent sand passes down the inclined tube into the lower end of the Cylinder,
from which it may be removed from time to time, and used over again.
When the plunger E, is raised by pressing down the lever G, it creates a partial
vacuum in the Cylinder so that upon the valve V2 heing opened, a rush of air takes
place through the blast pipe P, carrying the sand with it as before described; if
required the blast may be arrested before the completion of the stroke by closing the
valve by means of the lever K, and the plunger returned to its former position ready
for another operation-The outlet valves VI permit the air in the Cylinder to escape
when the plunger is being lowered.
Although the foregoing description applies to a machine in which the current of air,
or blast, is produced by creating a partial vacuum (or exhaustion) a similar result
may be obtained by adapting the Cylinder and plunger to create a blast by
compression.
When the operation of the sand blast upon the article is completed, the blast is
stopped, either by the operator closing the Valve V2, or by the completion of the stroke,
and the plunger returns by gravity to its lowest position, ready to be again set in
motion, during which interval the article is readjusted, or replaced by another.
A Sand-blast apparatus as above described and operated by manual or other power

page_text: is especially adapted for marking articles of glass with small designs which can be
blown on at one operation.
For purposes in which a continuous blast is necessary I combine two or more such
exhausting Cylinders, operated by steam or other power in any convenient manner,
and connected to a sand-blast apparatus.
I do not confine myself to the exact details of construction as described and
illustrated, as it will be evident that such may be varied without departing from the
invention, but;
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1st. The combination of a sand blast machine with a reciprocating blowing, or
exhausting apparatus, producing an intermittent blast, substantially as hereinbefore
described, for the purpose specified.
2nd. The combination of a pump Cylinder A provided with inlet and outlet Valves
a plunger E, and a flexible or elastic connecting tube I, for blowing or exhausting for
sand blast purposes, substantially as hereinbefore described and shown.
Dated the 18th day of May 1888.
ROBT. F. DRURY, Fel. Inst. P.A.,
Bank Buildings, George Street, Shoffield,
Agent for the Applicant.