Improvements relating to the Cleaning of Castings and other Articles by means of the Sand-blast.
Year: 1899

page_text: Date of Application, 28th June, 1899-Accepted, 5th Aug., 1899
COMPLETE SPECIFICATION,
Improvements relating to the Cleaning of Castings and other Articles
by means of the Sand-blast.
I, JEREMIAH EUGENE MATHEWSON, of Broadheath, in the County of Chester,
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:-
This invention relates to the cleaning of castings and other articles from
sand and scale by means of the sand-blast, in what are known as "tumbling
barrels." Such an apparatus is described in the Specification of Letters Patent
granted to me, dated December 24th 1895, No. 24,715, but in such apparatus a
good deal of time is wasted in taking the cleaned castings out of the barrel, and
the object of the present invention is to obviate the necessity for stopping the
apparatus, to remove the cleaned castings, and to refill the barrel with fresh
castings to be treated.
To this end, the invention consists in so constructing the apparatus, that a
continuous progressive movement through the barrel may be given to the
castings or other articles to be cleaned.
In the accompanying drawing,
Fig. 1 is a side elevation of the whole apparatus, with the tumbling barrel
and its accessories in section.
Fig. 2 is a plan view of the same.
Fig. 3 is a view of the entering end of the barrel; and
Fig. 4 is a cross section on the line 1-2, Fig. 1.
is the sand-blast apparatus, working by compressed air, the general con-
struction of which is the same as that described in the Specification of Letters
Patent granted to me dated June 22nd 1893, No. 12,306, except that it has four
or more sand-blast pipes, instead of one, as is usual, and in the upper part is
arranged what is known as a cyclone dust separator, to separate the good work-
ing sand from the dust and air, as indicated by dotted lines in the figure. This,
however, forms no part of the present invention, and further description is
therefore unnecessary.
The apparatus a, may, however, be worked by steam, if desired.
bis the tumbling barrel, which is mounted on driven rollers in a manner
now well known, so that the barrel is rotated by friction of contact.
This barrel is set at a slight inclination, as shown, so that the articles will
receive a continuous progressive movement as the barrel rotates. Usually the
barrel will be about eight feet long, and the inclination should be such that the
articles will pass through it in about 15 minutes.
At its front end, the barrel b rotates in a fixed shield c, which is provided
with a hopper d, to receive the articles to be cleaned, and from which they pass
through an opening (closed by a rubber flap or door e) in the shield c, into the
barrel a.
At its rear end, the barrel enters a box or casing f, the bottom of which is
hopper-shaped, one portion y extending beyond the wall of the casing, as shown.

page_text: Inside the box f is arranged an inclined grating h, on to which the articles,
when cleaned, coming from the barrel b, fall, and roll down into the part 9 of
the hopper outside the wall of the box f.
An opening is made in the wall of this box f, which is closed by a rubber flap
or flexible door i, so arranged that it will allow the cleaned articles to pass and
close back afterwards.
The sand and dust pass through the grating h, and, by reason of the partial
vacuum in the upper part of the sand-blast apparatus, are drawn into and along
the pipe (the horizontal part of which I term the conductor), back into the
sand-blast apparatus a, by the vertical part of the pipe j, which I term the
elevator.
k, k¹,,, represent a cluster of sand-blast pipes proceeding from the sand-
blast apparatus, and carried by the shield c. These pipes project into the
barrel b, and each pipe of the cluster is provided with a sand-blast nozzle 1, of
usual construction.
and
The pipes, it will be seen, are of varying lengths, for an obvious reason,
the nozzles are arranged to point forwards, downwards, and sideways, in each
case at about an angle of 45 degrees.
The articles to be treated are thrown into the hopper d, and gradually work
along the barrel b, coming consecutively within the line of action of each nozzle,
and being acted upon thereby, finally tumbling on to the grating and into
the portion g, from which they are removed by hand.
The barrel is caused to rotate about 4 times in a minute, and each article
takes about 15 minutes to travel along it to the grating, and it comes out
perfectly clean.
In the usual arrangement of tumbling barrel, it is necessary to stop its
movement, in order to remove the cleaned castings and refill the barrel, which
takes from 15 to 30 minutes, and thus the improved arrangement of tumbling
barrel provides for an immense saving of time as well as of labour.
m is the inlet for the compressed air and is the exhaust or outlet for the
air and dust.
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
I claim is:-
1. An apparatus for cleaning castings and other articles by means of the
sand-blast, constructed, arranged, and operating as herein shown and described.
2. In apparatus for cleaning castings by means of the sand-blast, the com-
bination of an inclined rotating tumbling barrel with a fixed shield carrying a
hopper and the sand-blast pipes, and a fixed chamber provided with a grating
to receive the cleaned articles, as shown and described.
3. In cleaning castings and other articles in a tumbling barrel by the sand-
blast, giving to the articles to be cleaned a continuous progressive movement
through the barrel, as and for the purpose set forth.
4. In apparatus for cleaning castings in a tumbling barrel by the sand-blast,
a continuously rotating tumbling barrel set at an angle downwards from the
horizontal, as and for the purpose set forth.
Dated this 28th dow of Lun 1000