IMPROVEMENTS IN MACHINES FOR GRINDING AND SURFACING ARTICLES MADE OF IRON OR STEEL
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by James Archibald Jaques and
John Thomas Oakley at the Office of the Commissioners of Patents,
with their Petition, on the 20th February 1872.
We, JAMES ARCHIBALD JAQUES, of Tottenham, in the County of
Middlesex, Chemist, and JoHN THOMAS OAKLEY, of Grange Road, Ber-
mondsey, in the County of Surrey, Engineer, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN MACHINES FOR GRINDING
AND SURFACING ARTICLES MADE OF IRON OR STEEL," to be as follows:-
:-
Our Invention of improvements in machines for grinding and sur-
facing articles made of iron or steel relates to improvements upon an
Invention for which we (in conjunction with John Americus Fanshawe)
obtained Letters Patent, dated 8th March 1869, No. 697, and has for its
object to render the Invention therein set forth more generally useful.
The Invention described under our former Patent consisted of a novel
form of chuck to be adapted to a lathe for the purpose of holding rings,
plates, discs, or other analogous articles while they are being ground.
We have found by experience that this improved form of chuck de-
scribed under our former Patent is only applicable for a very limited
class of articles, and cannot conveniently be used either for very small
articles or very large ones unless a number of chucks of various

page_text: sizes in proportion to the size of the article to be operated upon be
employed.
Our present Invention consists first in constructing the chuck in an
improved manner so as to render it more generally useful, and, second,
in adapting a magnetic holder constructed on the same principle to
planing and surfacing machines for the purpose of holding the metal
article steady while under operation.
In constructing a magnetic chuck for a lathe according to our present
Invention we form the chuck of two circular discs, one of which is
divided across its centre into two parts, which are separately connected
with the bottom discs by pillars or studs round which is coiled insulated
copper wire, so that by means of a galvanic battery or magneto-electric
machine the chuck will be converted into a powerful electro-magnet,
which when an article made of iron or steel is placed thereon will hold
it firmly.
The next improvement consists in adapting to the bed of a planing or
surfacing machine a magnetic holder made of two oblong plates of
metal connected together by pillars or cross pieces, the upper plate
being divided, as in the instance of the chuck, into two parts, which
will form the opposite poles of the magnet. Round the connecting
plates or pillars are wound coils of insulated copper wire, as in the
former instance. For the purpose of strengthening the divided upper
plate the slot or opening between the poles may be filled in with brass,
copper, or other non-magnetic substance.
As a modification of the above the magnet may be formed of one
long plate of iron bent up and doubled over, and the two limbs of the
magnet may be surrounded with insulated wire, as in the other case.
The articles to be operated upon will be firmly held by these magnetic
holders on the bed of the planing or other machine, and may be ground
or surfaced by emery wheels or cutting stones to which a rapid rotary
motion and also a slow lateral motion is communicated, while the bed
or chuck is either rotated as in a lathe or reciprocated as in a planing
machine.