IMPROVEMENTS IN MACHINERY FOR REDUCING BULLDOG OR OTHER HARD SUBSTANCES
Year: 1868

page_text: LETTERS PATENT to Benjamin Walker, of Leeds, Engineer, and John
Frederick Augustus Pflaum, also of Leeds, Engineer, for the Inven-
tion of "IMPROVEMENTS IN MACHINERY FOR REDUCING BULLDOG OR OTHER
HARD SUBSTANCES."
Sealed the 1st April 1869, and dated the 9th October 1868.
PROVISIONAL SPECIFICATION left by the said Benjamin Walker and
John Frederick Augustus Pflaum at the Office of the Commissioners
of Patents, with their Petition, on the 9th October 1868.
We, BENJAMIN WALKER, of Leeds, Engineer, and JOHN FREDERICK
AUGUSTUS PFLAUM, also of Leeds, Engineer, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN MACHINERY FOR REDUCING
BULLDOG OR OTHER HARD SUBSTANCES," to be as follows:-
This Invention has for its object improvements in machinery for
reducing bulldog and other hard substances. For this purpose we
employ a strong metal pan, the internal form of which is by preference
an inverted truncated cone, it is open at the bottom and the sides are

page_text: checkered or fluted. In or near the centre of the pan is mounted a
conical shaped pestle, which is also an inverted truncated cone, but
its incline is less than that of the pan, it may also be checkered or fluted.
This pestle is by preference fixed to the piston rod of an ordinary steam
hammer, which piston rod is firmly guided. The action of the steam
hammer is such that when the piston is at the top of its stroke the
pestle will be in such a position as to leave a space between itself and
the lower edge of the pan sufficient for the escape of the reduced
material. The pestle may be moved up and down by an ordinary
eccentric motion, or it may be coupled direct to the piston of an
ordinary steam engine. The size of the opening for the escape of the
reduced material may be varied to suit the work to be done.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Benjamin Walker and John Frederick Augustus
Pflaum in the Great Seal Patent Office on the 8th April 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, BENJAMIN
WALKER, of Leeds, Engineer, and JOHN FREDERICK AUGUSTUS PFLAUM,
also of Leeds, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of October, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said Benjamin Walker and John Frederick
Augustus Pflaum, Her special licence that we, the said Benjamin
Walker and John Frederick Augustus Pflaum, our executors, adminis-
trators, and assigns, or such others as we, the said Benjamin Walker
and John Frederick Augustus Pflaum, our executors, administrators, and
assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should
and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, an Invention for "IMPROVEMENTS IN MACHINERY FOR REDUCING BULLDOG
OR OTHER HARD SUBSTANCES," upon the condition (amongst others) that we,
the said Benjamin Walker and John Frederick Augustus Pflaum, our
executors or administrators, by an instrument in writing under our or

page_text: their hands and seals, or under the hand and seal of one of us or
them, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that we, the said Benjamin Walker and John
Frederick Augustus Pflaum, do hereby declare the nature of the said
Invention, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement
thereof, that is to say :-
This Invention has for its object improvements in machinery for
reducing bulldog and other hard substances. For this purpose we
employ a strong metal pan, the internal form of which is by preference
an inverted truncated cone, it is open at the bottom, and the sides are
checkered or fluted. In or near the centre of the pan is mounted a
conical shaped pestle, which is also an inverted truncated cone, but
its incline is less than that of the pan, it may also be checkered or fluted.
This pestle is by preference fixed to the piston rod of an ordinary steam
hammer, which piston rod is firmly guided. The action of the steam
hammer is such that when the piston is at the top of its stroke the
pestle will be in such a position as to leave a space between itself and
the lower edge of the pan sufficient for the escape of the reduced
material. The pestle may be moved up and down by an ordinary
eccentric motion, or it may be coupled direct to the piston of an
ordinary steam engine. The size of the opening for the escape of the
reduced material may be varied to suit the work to be done.
In the Drawing hereunto annexed is shewn a machine constructed
according to our Invention, in the manner we prefer. a is the
Iconical metal pan open at the bottom as shewn, and 6 is the conical
pestle fixed to the piston rod of a steam hammer c of ordinary construc-
tion, so that when the hammer is set in motion the pestle is alternately
raised and driven downwards, thus crushing any material that is between
the pestle and the pan, until the material is sufficiently reduced to pass
away through the opening at the bottom of the pan.
The sides of the pestle and pan may either be smooth surfaces
as shewn in the Drawing, or they may be checkered or corrugated

page_text: with the corrugations running either vertically or horizontally of
the pan and pestle, but vertical corrugations are preferred.
In witness whereof, we, the said Benjamin Walker and John
Frederick Augustus Pflaum, have hereunto set our hands and
seals, this Fifth day of April, in the year of our Lord One 5
thousand eight hundred and sixty-nine.
Witness,
W. H. TANNETT,
Apl. 5th 1869.
B. WALKER.
(L.S.)
J. F. A. PFLAUM. (L.S.)