IMPROVEMENTS IN LITHOGRAPHIC PRINTING PRESSES
Year: 1856

page_text: (This Invention received Provisional Protection, but notice to proceed with the
application for Letters Patent was not given within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by Charles Louis Frederick Helrigel
at the Office of the Commissioners of Patents, with his Petition, on the
5th September 1856.
I, CHARLES LOUIS FREDERICK HELRIGEL, of Great James Street, Bedford
Row, in the County of Middlesex, do hereby declare the nature of the
Invention for "IMPROVEMENTS IN LITHOGRAPHIC PRINTING PRESSES," to be as
follows:-
This Invention has for its object improvements in lithographic printing
presses. For these purposes the bed or table on which the stone is placed is
arranged to slide on a suitable frame. Motion is communicated to the table
or bed by means of a toothed rack, which is not fixed to the table or bed, but
is arranged to slide a distance before it is fixed to the table or bed, in order
that the stone may remain stationary for a time till the scraper is brought
down to its lowest position, and such bringing down of the scraper, and the
retaining of the stone from movement, is made to depend on adjusting stops
and suitable gearing, so that the rack may be moved a greater or less distance
before the scraper is brought down, and consequently the stone be made to
move a greater or less distance under the scraper before the scraper is brought
down to act on the stone. The tympan is hinged to the moving table or bed
of the press, so that when the table or bed is moved, the tympan (which is at

page_text: other times kept up by a weighted cord) in passing under a roller is caused
to close down on the stone. Motion is given to the toothed rack before
mentioned by means of a cog wheel on an axis below the table or bed, and
such axis receives motion by a cog wheel thereon gearing into a cog wheel
on another or main axis, which receives motion by a hand wheel or hand bars
or star fixed on the main axis. In order to bring down the scraper the cog
wheel on the main axis is arranged to come into gear with the teeth of a
sector wheel on a third axis. To this sector wheel is a fixed arm, to which is
attached a connecting rod with a projection thereon, which is for the purpose
of acting on a lever which locks a pinion which is carried by the sector wheel,
and this pinion is so arranged that it at all times presents a tooth to take
into the cog wheel on the main axis, so that when the sector wheel has been
moved to its greatest extent the tooth of the pinion comes into gear and
causes the sector wheel to be moved one tooth further, and then the pinion is
unlocked and is caused to revolve by the cog wheel on the main axis; on
reversing the action of the main axis the pinion is again locked, and by such
means the sector wheel is moved back by the cog wheel on the main axis.
The connecting rod attached to the arm of the sector wheel gives motion to
a lever, which by another connecting rod gives motion to another lever, which
is pin-jointed to a connecting rod on the lever which carries the scraper, and
the scraper is suspended to the last-mentioned lever, there being suitable
provision made for adjusting the position and pressure of the scraper. The
cog wheel on the main axis is caused to gear with the sector wheel by means
of an adjustable stop on the bed or table acting on a lever which moves the
arm on the sector wheel a distance so as to bring these wheels into gear.