IMPROVEMENTS IN APPARATUS FOR GLAZING PAPER."
Year: 1881

page_text: LETTERS PATENT to Thomas Ruddiman Johnston, of the City and County of
Edinburgh, North Britain, for an Invention of "IMPROVEMENTS IN APPARATUS
FOR GLAZING PAPER."
PROVISIONAL SPECIFICATION left by the said Thomas Ruddiman Johnston
at the Office of the Commissioners of Patents on the 10th June 1881.
THOMAS RUDDIMAN JOHNSTON, of the City and County of Edinburgh, North
"IMPROVEMENTS IN APPARATUS FOR GLAZING PAPER.”
Britain.
This Invention relates to improvements in apparatus for imparting a glazed
surface to sheets of paper, to fit them for use for lithographic and the best class of type
printing, and other uses where a highly glazed or polished surface is necessary, and
has for its object to economize labour, and supersede the ordinary arrangement for
this purpose, wherein a pile of zinc or copper plates with the sheets of paper between
them are passed between rolls.
According to this present Invention the apparatus will consist of a pair of rolls,
to which an intermittent motion in the same direction will be given by suitable
mechanisin, so that they are caused to make one revolution, then stop, then make
another revolution, and so on. Each roll has a longitudinal groove in it extending
to within a distance from the ends of the roll, which will give a sufficient bearing of
the rolls upon each other at this part, the sides of the said groove diverging so
that it is wider at bottom than top, and the outer edges of the said groove being
curved or bevelled. A highly polished sheet of zinc or copper is passed around
each roll, the ends of the said sheet being turned into the groove, and two wedge
shaped strips are placed in the groove and fixed so as to bear upon the ends of the
zinc plate, and cause them to bear upon the sides of the groove in the roll. The
said wedge shaped strips are fixed in place by screws with wedge shaped or conical
heads screwed into the rolls between the said strips, and engaging in recesses in the
said strips to prevent longitudinal movement. Other equivalent means may be
employed for fastening the zinc plates by pinching their ends between the sides or
bottom of the grooves, and wedges, or screws, or other securing appliances without
Posica G11

page_text: making holes in the plates. The rolls in making their intermittent revolutions
start from a position in which the groove in each roll is opposite the groove in the
other, and a sheet of paper being fed in between the rolls on the rolls revolving,
the sheet is carried through the rolls between the zinc sheets thereof and glazed,
the rolls then stop and another sheet is fed to them, when they again revolve and
glaze this sheet, and so on. The curved edges of the grooves prevent the cracking
or damaging of the zinc plates by the pulling upon the same on the one side and
the bagging upon the other. The bearings of the top roll may be mounted upon
screws actuated by bevel wheels gearing with other bevel wheels upon a shaft
turned by a hand wheel, so that by this means the pressure between the rolls may
be adjusted and the upper roll raised from the lower roll when the zinc plates are
to be removed, for there will be zinc plates provided to be placed upon the rolls
(and fixed thereto by the arrangement before described) for each size of sheet to be
glazed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Ruddiman Johnston in the Great Seal Patent Office on
the 6th December 1881.
THOMAS RUDDIMAN JOHNSTON, of the City and County of Edinburgh, North
Britain. "IMPROVEMENTS IN APPARATUS FOR Glazing PapeR."
My said Invention relates to improvements in apparatus for imparting a glazed
surface to sheets of paper to fit them for use for lithographic and the better class
of type printing and other uses where a highly glazed or polished surface is
necessary, and my said Invention has for its object to economize labour and
supersede the ordinary arrangement employed for this purpose, wherein a pile of
zinc or copper plates with the sheets of paper between them is passed between
rolls.
The apparatus constructed according to ny said Invention consists of a pair of
rolls, to which an intermittent motion in the same direction is given by suitable
mechanisin, so that they are caused to make one revolution, thon stop, then nako
another revolution, and so on. Each roll has a longitudinal groove in it extending
to within a distance from the ends of the roll so as to leave a continuous portion of
the periphery of the rolls at each end to give a sufficient bearing of the rolls upon
each other at these parts. The sides of the said groove diverge, so that the groove
is wider at bottom than top, and the outer edges of the said groove being curved or
bevilled. A highly polished sheet of zinc or copper is passed around each roll, the
ends of the said sheet being turned into the groove and two wedge shaped strips of
the length of the groove are placed in the grooves of each of the rolls and fixed so
as to bear upon the ends of the metal plate in the said groove, and pinch them
between the said strips and the sides of the said groove. The said wedge shaped
strips are fixed in place by screws with wedge shaped or conical heads screwed
into the rolls between the said strips, and engaging in recesses in the said strips to
prevent longitudinal movement.
Other equivalent means may be employed for fastening the metal plates by
pinching their ends between the sides or bottom of the grooves, such as wedges or
screws, or other securing appliances, without making holes in the plates. The rolls
in making their intermittent revolutions start from a position in which the edge of
the groove in each roll is opposite the corresponding edge of the groove in the other
roll, and a sheet of paper being fed in between the rolls, on the rolls revolving the
sheet is carried through the rolls between the metal sheets thereof and glazed.
Owing to the before mentioned intermittent motion imparted to the rolls they then
stop, and another sheet is fed to them, when they again revolve and glaze this
sheet, and so on. The curved edges of the grooves prevent the cracking or
damaging of the zinc plates by the pulling upon the same on the one side and the
bagging upon the other. The bearings of the top roll may be mounted upon
screws actuated by bevil wheels, gearing with other bevil wheels upon a shaft
turned by a hand wheel, so that by this means the pressure between the rolls may
be adjusted and the upper roll raised from the lower roll when the metal plates are
to be removed, for there will be metal plates provided to be placed upon the rolls
(and fixed thereto by the arrangement before described) for each size of sheet to be
glazed.
And in order that my said Invention may be properly understood I now proceed
more particularly to set forth the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, reference being had to
the accompanying Drawings, and to the letters and figures marked thereon, that
is to say,
Figure 1 represents in front elevation a machine constructed according to my

page_text: Invention, and Figure 2 is a side elevation of the same shewing the gearing wheels
in dot and pick lines; Figures 3, 4, and 5 represent details as hereinafter described.
In the framing A are mounted the rolls B and the bearings of the driving shaft
and gearing by which the before mentioned intermittent motion is imparted to the
said rolls. This gearing is arranged as follows:-The driving shaft C has keyed
upon it the fast or driving pulley c, the loose pulley c³, and the fly wheel c³. It
also has keyed upon it a pinion which gears with a toothed wheel e keyed upon
the intermediate shaft E, upon which shaft is also keyed a pinion c² which gears
with the toothed wheel of keyed to the shaft F, and thus transmits motion to the
said shaft F. Upon the said shaft F is also keyed a wheel G, about the one half
of the periphery of which is toothed, the remaining portion being plain. The
toothed portion of this wheel G gears with the toothed wheel H keyed upon the
axis of the lower roll B, the said axis also having keyed upon it another toothed
wheel b gearing with an exactly similar toothod wheel b² keyed upon the axis of
the upper roll B, by which wheels the exact speed of the one roll is transmitted
to the other. The two wheels G and H by which the intermittent rotation of the
rolls is effected are shewn separately in Figure 3. Upon one or both sides of each
wheel are cast projections marked g and respectively for bearing upon each other
to start the rolls after each period of rest between each rotation, that is to sny,
after the untoothed portion of the wheel G has passed before the wheel H, and
when the toothed portion of the said wheel G is about to gear with the said wheel H.
Each roll B has fixed upon it a highly polished sheet of zinc or copper i, the fixing
of the said sheet upon each roll being effected as follows:-A longitudinal groove b
is made in each roll, as shewn in Figure 4, which is a transverse section of the
pair of rolls, the said groove extending from within a short distance of the one end
of the roll to within a short distance of the other end of the roll so as to lenve
cylindrical or continuous portions at each end of both rolls to form a continuous
bearing of the rolls upon each other at these parts, and also prevent the endways
movement of the strips which are inserted in the grooves b³ to secure the ends of
the plates in the said groove. The sides of the groove b³ diverge so that the said
groove is wider at bottom than at top, the outer edges of the said groove being
bevilled as shewn. The wedge shaped strips K the length of the groove 6s are
placed in the said groove so as to bear upon the ends of the plate turned into
the said groove, and screws with wedge shaped or conical heads are screwed into
the rolls between the said strips k, so that the conical heads of the said screws urge
the strips outwards, and cause them to grip firmly the ends i² of the plates i
between themselves and the edges of the grooves bs. There may be recesses in the
inner sides of the strips for the heads of the screws to take into. Figure 5 shews
a modification of this means of fastening, wherein the two strips k are replaced by
one double wedge shaped strip urged down by a screw 12 (or several such screws)
k³
into the wedge shaped recess b³ in the rolls, so as to pinch the ends of the plate
between itself and the sides of the said recess, as before described. In this arrange-
ment in order to facilitate the removal of the wedge shaped strip when fresh
metal plates are to be inserted, screws may be inserted into screw boxes tapped
therein, which screws on being tightened press upon the bottom of the groove and
force the said strip outwards. Other equivalent means for fastening the plates i
by pinching their ends against the sides or bottom of the grooves by wedges
and screws or analogous devices which render unnecessary the making of holes in
the plates may be adopted. The rolls B in making their intermittent revolutions
start from the position shewn in Figure 4, and a sheet of paper to be glazed being
fed between the rolls when they make their revolution, the said sheet is carried
between the rolls and glazed by the plates i. The pressure between the rolls may
bo rendered adjustable, and the separation of the rolls for the removal of the
plates i may be effected by means of the ordinary device for adjusting the pressure
of rolls consisting in forming the bearings of the upper roll in vertically sliding
blocks raised and lowered by screws operated by the bevilled wheels m thereon,
and gearing bevil wheels upon a shaft provided with a hand wheel m³.

page_text: The zinc or copper plates can be readily removed and others substituted corre-
sponding to the width of sheets of paper to be glazed. As before stated the upper
edges of the grooves b³ are bevilled. The bevil at the one side 6 is greater than
that at the other side 6. The whole pull of the plates is at 65. At b* where the
pressure ceases the greatness of the bevil prevents any liability of the plates to
crack, but the said plates in this case simply bag out at this part, as shown in
Figure 4.
When the machine is in operation, as before explained, the rolls will have
periods of rest alternating with complete revolutions of the said rolls. The rolls
start each revolution from the position shewn at Figure 4, a sheet of paper being
fed between them at each period of rest at the succeeding revolution of the rolls is
taken through, and its surfaces glazed during its passage by the said plates i carried
by the said rolls.
Owing to there being no holes made in the said plates i should they increase
much in length, I can readily cut then down to the proper length, and also the
said plates can readily be removed, and other plates according to the size of paper
to be glazed be readily fixed on in their place. The wheel G may be made larger
or smaller so as to give a larger or smaller blank or inactive space to increase or
diminish the period of rest between each revolution of the rolls.
Having now described and particularly ascertained the nature of my said
Invention, and the system, mode, or manner in or under which the same is or may
be used or practically carried into effect, I would observe in conclusion that what
I consider to be novel and original, and therefore claim as the Invention secured
to me by the hereinbefore in part recited Letters Patent is,―
First. The general arrangement and combination of parts constituting the
apparatus for glazing paper, essentially as hereinbefore described and illustrated in
the accompanying Drawings.
Second. In apparatus for glazing paper, the means for giving an intermittent
motion to the glazing rolls, that is to say, periods of rost to allow of the insertion
of the sheets alternating with revolutions of the rolls for effecting the glazing,
essentially as hereinbefore described and illustrated in the accompanying
Drawings.
Third. In apparatus for glazing paper, the means for fixing the metal glazing
plates upon the rolls, consisting of a groovo in the rolls into which the ends of the
plates are passed, and confined therein by being pinched between the sides of the
said grooves and securing bars and screws or their equivalents, essentially as
hereinbefore described and illustrated in Figures 4 and 5 of the accompanying
Drawings.
Fourth. In apparatus for glazing paper, the bevilling of the edges of the groove,
as shewn in Figure 4 of the accompanying Drawings, so as to prevent the cracking
and allow of the bagging of the glazing plates.
In witness whereof, I, the said Thomas Ruddiman Johnston, have hereunto
set my hand and seal, this Thirtieth day of November, One thousand eight
hundred and eighty one.
T. RUDDIMAN JOHNSTON. (L.S.)