Improvements in Sand Blast Apparatus.
Year: 1890

page_text: Date of Application, 15th .Mar., 1890-Accepted, 19th Apr., 1890
Improvements in Sand Blast Apparatus.
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:-
Among other operations to which the sand blast is adaptable, is the cleaning of
castings, but hitherto its use for this purpose has been limited, owing to the want
of a convenient apparatus.
Steam is the most convenient motive force for propelling the sand, and I have
invented a mode of withdrawing the steam from the blast before it reaches the article
to be operated upon, which mode forms the subject of Letters Patent granted to me
No. 15980 dated the 5th day of December 1884, and it remained to me to devise
means for rendering this mode available in the cleaning of castings, and for other
purposes for which the ordinary sand blast apparatus is not suitable.
In this class of work, it will be evident that the articles, in most cases, will be too
heavy to be moved about, in order to bring their various parts in position to be
reached by the sand blast, and therefore the form of the apparatus used for such
work must be of a character to permit of the position of the jet being readily
changed, as required, so that the blast may be directed to all parts of the object
under treatment.
Now the object of the present invention is to provide a convenient, simple, and
efficient apparatus, which will permit of the sand blast being used for what I may
term "heavy work," such as cleaning castings, cutting stone, and similar hard
materials, in contradistinction to cutting or ornamenting glass and similar materials,
which may be termed "light work."
In the accompanying drawing, I have shown in side elevation, partly in section, my
improved apparatus for cleaning castings &c.
A is the steam pipe, and B a steam drying chamber of the construction described
in the specification of Letters Patent granted to me, No. 2456, dated the 17th day of
February 1887, or of any other construction.
This chamber is connected by a flexible pipe B₁ with the steam jet C. The blast
pipe C is arranged opposite to the jet C, and it has a trumpet mouth continuation C².
The jet C, and the blast pipe C, fit into a socket X, which has a funnel shaped inlet c,
to receive the sand from a sand hopper D. Around the end of the trumpet mouth C
is arranged a separating chamber E, which has an opening opposite to the mouth of
the trumpet C, and is also connected by a flexible tube E' with a fixed box or settling
chamber E. In connection with this fixed box E, is the exhauster F, provided with
a trunk F³, the steam for producing the exhaust being conveyed from the dryer B by
the pipe f
The jet (, blast pipe C, and bell mouth C3, are mounted in a support H, carried by
a sling or frame H, which is in turn carried by tackle J, pendent from the ceiling or
an overhead beam. The tackle will be provided with an automatic gripping mechanism,
so that the apparatus may be readily fixed at any desired height, according to the
requirements of the work in hand.
In order to provide for a larger amount of movement than could be obtained with
fixed tackle, I inay attach the tackle to a roller or pulley K, which runs on a swivel
guide or track L, secured to the ceiling or overhead beam.
The support His provided with a long handle, by which the workman can change
the position and direction of the blast while standing out of reach of the rebounding
grains of sand.
The sand is placed in the hopper D), which is provided with a suitable valve, and is

page_text: allowed to escape in regulated quantities into the funnel c, from which it falls in front
of the jet of steam.
The sand is carried by the steam along the blast pipe C', and through the
trumpet mouth, by which time it has gained a high velocity, and is projected
through the opening in the chamber E onto the article with great force.
The steam expands in the trumpet mouth C³, and, on issuing therefrom with the
sand, is met by a slight current of air entering the separating chamber E by the oxit
opening, and induced by the exhauster F, which separates the steam from the sand,
and draws it down the pipe E¹ without appreciably diminishing the velocity of the
sand.
As no steam escapes, the workman can always see what he is doing. The
sand, which is dry (having been separated from the steam), falls onto the floor,
and is collected from time to time for reuse in the hopper D.
The blast pipe C¹, which wears out, is readily removable for renewal.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. In apparatus for cleaning castings and for operating or other work which cannot
he conveniently done by a stationary apparatus by means of the "sand blast," and in
which the propelling steam is separated from the sand by a counter current of air,
the combination with the blast apparatus, supported or suspended in such a manner
that the direction and position of the blast may be quickly and readily changed
according to the requirements of the work in hand, of a separating chamber carried by
the blast apparatus, and flexibly connected with a fixed settling chamber and an
exhauster, as and for the purpose set forth.
2. The sand blast apparatus consisting of a stationary exhaust apparatus and settling
chamber, a blast apparatus provided with a separating chamber flexibly connected
with the exhaust, a sand hopper carried by a sling or frame, which also carries the
blast apparatus, so that the relative positions of the hopper and blast apparatus are
ensured, and tackle provided with automatic gripping mechanism, and which permits
of the position and direction of the blast apparatus being changed, all as described
and illustrated.
Dated this 15th day of March 1890
NEWTON & SON,
Agents for the Applicant.