Improvements relating to the Ornamentation of Glass, and in Apparatus to be Used therefor.
Year: 1889

page_text: Date of Application, 15th Apr., 1889
Complete Specification Left, 16th Oct., 1889-Accepted, 23rd Nov., 1889
PROVISIONAI. SPECIFICATION.
[Communicated from abroad by BENJAMIN CHEW TILGHMAN, of the City of
Philadelphia, United States of America, Gentleman.]
Improvements relating to the Ornamentation of Glass, and in
Apparatus to be Used therefor.
I JEREMIAH EUGENE MATHEWSON of Bellefield Works, Sheffield in the County of
York, Engineer, do hereby declare the nature of this invention (as communicated to
me from abroad) to be as follows:-
In the frosting of glass by the sand-blast, the practice hitherto has been to use
the sand in a dry state, and to propel it by a current of air or steam.
The fineness of the frosting produced depends chiefly on the minuteness of the grain
of the sand used, and next, on the lowness of velocity given to it. The finest possible
frosting is desirable in some cases, as, for example, when globes or other articles are
to be ornamented, by being first frosted and then partly protected by patterns, and
finally treated by fluoric acid, so as to render bright the unprotected parts. The
minuteness of the grains of sand that can be used in a dry state in the sand blast
process is limited to the size that will flow evenly so as to give a regular feed. Very
fine dry sand will not flow, but on account of the large frictional resistance of its
particles, as compared with their weight, it clings together, and will stand in a vertical
wall, or even arch over.
The object of this invention is to increase the rapidity of the operation, to secure a
finer kind of frosting than heretefore, and to provide apparatus for effecting the same.
To this end, I use sand in the form of very fine powder (preferably as fine as flour),
mixed with water or other liquid to form a fluid abrasive mud, which can be fed
evenly and regularly. This mud is propelled or projected against the glass by a jet of
steam, air, or gas, at considerable pressure, or the desired velocity may be given in
any other known way. When the sand is used in the state of fine powder, the number
of grains in a given weight is immensely increased (inversely as the cube of the
diameter of the grain), and as at a high velocity each grain makes its mark on the
glass, the frosting is done much quicker.
The avoidance of dust and the easy collection and reüse of the fluid mud are also
practical advantages. The frosting produced by the use of the fine powder in the
state of fluid mud can be made much finer than has hitherto been obtained, and it is a
distinct part of the invention to combine the use of the sand blast fed with fluid
abrasive mud, to produce a fine frosting on glass, with the subsequent use of fluoric
acid upon the frosted surface, parts of which may, if desired, be protected by suitable
patterns, so as to form ornaments.
By the term "sand," small particles of any hard substance capable of scratching
glass, is meant, and in the term fluoric acid, is included any mixture of fluoric acid or
the fluorides commonly used in the art of ornamenting glass.
In applying the sand blast, fed with fluid abrasive mud, to glass articles of a
rounded or cylindrical shape (lamp globes, for example) which are capable of being
rotated on an axis or spindle, I place the article in a box or casing having a movable
lid, and provided with a receptacle to contain the fluid mud, and into which it falls
after having been used. An agitator preferably a steam jet, keeps the mud in a state
of fluidity. The sand blast jet enters the side of the casing, and throws a stream of
mud towards its centre. The mud is supplied from the receptacle either by suction
or by a pump or otherwise. A ventilator pipe, actuated by a steam jet, draws the
waste steam from the casing into the air. The article is held by clamps on a
spindle capable of being rotated by a crank handle, which passes through a slot in the
casing, and can be worked from the outside. The centre of the article should be
open

page_text: placed nearly in the centre of the case. The spindle is mounted removably in a
frame, which is pivotted at its centre, so that the article can have a movement of
oscillation on this pivot, as well as a movement of rotation on the spindle. The pivot
is mounted on a radial arm or slide attached to the case, so that the whole frame can
receive a longitudinal motion across the stream of mud projected from the sand blast
jet. The object & effect of the combination of these three movements are, that a globe
of almost any shape can be manoeuvred so as to receive the stream of fluid mud nearly
perpendicularly on every part of its surface.
Another way of carrying out my invention (& thus avoiding a somewhat complicated,
movement at the expense of a more complicated apparatus), for the purpose of frosting
and ornamenting globular articles of glass, is to mount the article on a spindle, as
before mentioned, which has a rotary motion only, and to use a series of radial blast
jets. The jets will be placed farther apart as they near the poles, or they may be
placed equally distant apart, but smaller as they near the poles, corresponding with
the diminishing area of the zones as they approach the poles. This method is also
applicable to frosting & ornamenting globular articles by the ordinary air blast, using
dry sand.
The combination of a sand blast jet fed with fluid abrasive mud, with any or all
of the above devices for giving movements to the article, is a distinct part of my
invention.
D
COMPLETE SPECIFICATION.
Improvements relating to the Ornamentation of Glass, and in
Apparatus to be Used therefor.
I, JEREMIAH EUGENE MATHEWSON of Bellefield Works, 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:-
In the frosting of glass by the sand blast, the practice hitherto has been to use the
sand in a dry state, and to propel it by a current of air or steam.
The fineness of the frosting produced depends chiefly on the minuteness of the grain
of the sand used, and next on the lowness of velocity given to it.-The finest possible
frosting is desirable in some cases, as for example when globes or other articles are to
be ornamented by being first frosted and then partly protected by patterns, and finally
treated by fluoric acid so as to render bright the unprotected parts. The minuteness
of the grains of sand that can be used in a dry state in the sand blast process is
limited to the size that will flow evenly so as to give a regular feed. Very fine dry
sand will not flow, but on account of the large frictional resistance of its particles as
compared with their weight, it clings together, and will stand in a vertical wall, or
even arch over.
The object of this invention is to increase the rapidity of the operation, to secure a
finer kind of frosting than heretofore; and to provide apparatus for effecting the
same. To this end the sand is used in the form of very fine powder (preferably as
fine as flour), mixed with water or other liquid to form a fluid abrasive mud, which
can be fed evenly and regularly. This mud is propelled or projected against the glass
by a jet of steam, air, or gas, at considerable pressure, or the desired velocity may be
given in any other known way. When the sand is used in the state of fine powder,
the number of grains in a given weight is immensely increased (inversely as the cube
of the diameter of the grain), and, as at a high velocity each grain makes its mark on
the glass, the frosting is done much quicker. The avoidance of dust, and the easy
collection and reuse of the fluid mud, are also practical advantages.
The frosting produced by the use of the fine powder in the state of fluid mud, can
be made much finer than has hitherto been obtained, and the subsequent use of fluoric

page_text: acid upon the finely frosted surface, parts of which may if desired be protected by
suitable patterns, so as to form ornaments, is much more effective, and produces better
results than when the frosting has been produced with the comparatively coarse
dry sand.
"
By the term sand,"
," small particles of any hard substance capable of scratching
glass are meant, and in the term "fluoric acid" is included any mixture of fluoric acid
or the fluorides commonly used in the art of ornamenting glass.
In applying the sand blast, fed with fluid abrasive mud, to glass articles of a
rounded or cylindrical shape (lamp globes, for example), which are capable of being
rotated on an axis or spindle, the article is placed in a box or casing having a moveable
lid, and provided with a receptacle to contain the fluid mud, and into which it falls
after having been used. The sand blast jet is placed inside the casing, and throws a
stream of mud towards its centre.
The mud is supplied from a receptacle either by suction or by a pump or otherwise.
A ventilation pipe carries off the waste steam from the casing into the open air.
The article is held by clamps on a spindle capable of being worked by hand or
power from the outside. The centre of the article should be placed in the centre of
the case.
The spindle is mounted removably in a frame, which is pivotted at its centre,
so that the article can have a movement of oscillation on this pivot, as well as a
movement of rotation on the spindle. Or, the sand blast jet may be arranged so that
its direction may be readily changed during the operation.
The object and effect of the combination of these movements are, that a globe of
almost any shape can be manoeuvred so as to receive the stream of fluid mud nearly
perpendicularly on every part of its surface.
In the accompanying drawings, Fig. 1 is a sectional elevation of a machine for
frosting glass articles of a rounded form. Fig. 2 is a plan view, and Figs. 3, 4, 5, 6,
and 7 details which will be more particularly referred to hereafter.
AA is the sand blast apparatus which consists of a hopper shaped vessel in the
bottom of which the fluid mud collects after it has been used, and from which it is
conveyed by an inclined trough A¹ to a conical receptacle B. From this receptacle
the fluid mud is continuously raised by means of a pump C to a funnel C', from which
it is allowed to run through a pipe C to the sand blast jet D. The pump thus acts
also as the agitator to keep the mud in a state of fluidity.
The jet D is not shewn in Fig. 1, but it is set at an angle to the work to be done, as
is now well understood.
The pump C may be of any suitable kind, but it is preferred to use the form shown
in the drawing, which is of a well known type, the mud ascending and being
discharged from the hollow piston rod. The piston is worked at a slow speed by hand
or power.
Connected with the body A of the apparatus is a chimney or flue A² for carrying
off the exhaust steam or vapour and air. The draught in this chimney must be
sufficient not only to carry off the waste steam or vapour, but also to cause air to
enter all the joints in the apparatas, thus preventing the steam or vapour from finding
its way outward through said joints, and interfering with the proper working of the
apparatus.
E is a cylinder the upper end of which is closed by a conical or other shaped
cover E, and such cylinder is capable of an oscillatory motion on a vertical spindle or
pivot E within the hopper A. The step bearing for the spindle is enclosed in a
double case, as shown, to prevent the entrance of grit.
F is a spindle on which the glass globe or other rounded article is clamped for the
purpose of being frosted, and one end of this spindle fits into a spring centre F',
while the other end is squared to fit into a socket on the end of a shaft F, to which
rotary motion may be given by gearing, or in any other convenient manner. The
centre F, and the shaft F, are suitably carried by the cylinder E. By giving the
3 article to be frosted, rotary motion in front of the jet of mud, and by giving the
cylinder E an oscillatory motion, the whole of the rounded article will be exposed to

page_text: the action of the sand blast. The jet preferred is of the class in general use for
sharpening and scouring files.
The gearing, which is shown on an enlarged scale in figs. 3 and 4, consists of a
bevel wheel G on the shaft F, and a bevel wheel G¹ which is driven by a flexible
shaft from overhead, or in any other convenient manner. The rotary motion of the
cylinder E is effected by a rack and pinion motion actuated by a cam G on the
shaft F. This cam works in a fork at one end of a pawl lever G, the pawl G being
pivotted to the other end. The pawl takes into a series of pegs or teeth A³ forming a
rack arranged externally around the hopper A, the action being automatic.
When
the cylinder E has rotated the required distance, the pawl is reversed, and the cylinder
goes back again, the speed being so regulated that a globe is finished at each partial
rotation of the cylinder in either direction. The globe is removed and replaced by
another at the completion of each partial rotation.
The length of the rack may be varied, according to the requirements of the work in
hand, by means of the stop shown at fig. 5, one of which stops is placed over a peg at
the two points in the rack where the reversing operations are to be made.
When the pawl mounts this stop, it will not act on the rack, and the rotary motion
of the cylinder E will thus be discontinued.
G is a spring brake which bears against the side of the rack A³, to prevent the
cylinder over-running.
Figs. 6 and 7 show in two views an arrangement of counterweighted levers 'D',
carrying a plate D³, which, when the cover E' is opened, comes over the jet D, and
prevents the mud from splashing the hands of the attendant when removing and
attaching the globes.
Having now particularly described and ascertained the nature of the said Inven-
tion and in what manner the same is to be performed, as communicated to me
from abroad, I declare that what I claim is :
1. The process of ornamenting glass herein described, and consisting in the com
bined use of fluid abrasive mud projected by a jet of steam, air, or gas, or in any other
known way, and fluoric acid, as and for the purpose set forth.
2. In the frosting of glass by the sand blast, the use of a fluid abrasive mud
consisting of sand in the form of very fine powder, mixed with water or other liquid
as set forth.
3. In the frosting of glass by the sand blast, the use of a fluid abrasive mud in
combination with the apparatus as herein shown and described.
4. In apparatus to be used in the frosting of glass, the combination of a fixed
hopper A, a mud well B, a puinp C, a blast jet D, a rotating portion or cylinder E,
and a rotary spindle F, on which the article to be frosted is clamped, as herein shown
and described.
Dated this 16th do L 1000
NEWTON & SON,
Agents for the Applicant.