An Improved Combined Bronzing and Dusting Off Machine.
Year: 1895

page_text: Date of Application, 15th Mar., 1895
Complete Specification Left, 16th Dec., 1895-Accepted, 14th Mar.,
1896
PROVISIONAL SPECIFICATION.
An Improved Combined Bronzing and Dusting Off Machine.
I, CHARLES WRANGHAM WOODCOCK, 1ª Sumner Street, Southwark, in the
County of London, Engineer, do hereby declare the nature of this invention to be
as follows:-
My invention relates to a combined bronzing and dusting off machine. The
object of my said invention is to construct improved machines by means of which
bronze or other powder may be applied to a sheet which has been printed with
suitable ink or varnish to which the powder adheres, and by means of which the
superfluous powder may be dusted off the same.
It has heretofore been the general practice to use two separate machines for
these purposes one of which machines applies the powder and the other of which
dusts off the superfluous powder from the sheet that is to say from those parts of
the sheet upon which nothing was printed.
According to my invention I combine these two machines and apply the powder
and dust the sheet in one operation. I also improve the construction of both parts
of the machine in various details as hereinafter set forth.
The sheet of paper to which the powder is to be applied is fed between two
horizontal rolls the upper one of which is provided with a "ductor" or hopper
containing the powder which escapes through a slit in the bottom of the said
ductor direct to the upper surface of the said uppermost or bronzing roll. The
width of the slit in the bottom of the ductor is preferably capable of adjustment
according to the amount of bronze or powder required to be supplied to the sheet.
or more pairs of
After leaving the bronzing roll the sheet passes between one
feed or tension rolls which tend to maintain the paper straight and also press the
powder into the ink or varnish thereon. The pressure of these rolls may be
adjusted by any suitable means. The sheet is then carried forward on an endless
travelling band or apron carried by two rollers positively driven. Above the band
may be placed one or more plates or idle rolls which are merely driven by friction,
While the
and press the sheet on to the endless band with a gentle pressure.
sheet is on the endless band the superfluous bronze or other powder is brushed or
dusted off by one, two or more brushes arranged as hereinafter explained. The
sheet after leaving the dusting brushes is clear of powder except where the same
has adhered to the printed portions.
The dusting-off brushes I prefer to use have the form of endless bands of a
piled fabric such as plush or the like sewn to leather or other strips. In one
machine constructed according to this invention I provide two such bands which
are arranged above the apron and driven in a direction perpendicular to the
direction of motion of the sheet off which the powder is to be dusted. One of
Each dusting band is
said bands travels in an opposite direction to the other.
itself cleaned by being drawn at some part of its travel past a cleaning brush.
The said cleaning brush may be either fixed or rotating in an opposite direction to
the dusting band. When I use rotating cleaning brushes I may prevent the same
from becoming clogged with powder off the dusting bands by causing the hair or
bristles thereof to pass through the teeth of a suitable comb. By this means I
ensure the dusting bands being maintained in a clean condition and also I prevent
the powder from being shaken into the air which often happens with the ordinary

page_text: dusting bands which become full of bronze dust in a very short time. The dust
brushed off by the bands and brushes is caught in suitable receptacles provided for
the purpose.
I sometimes divide the ductor or hopper by means of partitions or I use a series
of separate boxes or small hoppers. suitably supported on the top of the bronzing
roll in place of a single long hopper or ductor. By this arrangement I am enabled
to apply different coloured powders to different pirts of the sheet in the same
operation. In order to avoid mixing the colours when the superfluous powders
are brushed off the sheet I use dusting bands the direction of motion of which is
not perpendicular to that of the sheet but is parallel therewith. The dusting
bands may be caused to move in either direction but when the face of the band
which is applied to the sheet moves in the same direction as the sheet the band
must be driven faster so as to brush the powder off the sheet at the end of the
travelling apron.
In those machines wherein the dusting bands move transversely to the direction
of motion of the apron I arrange under the top layer of the apron and immediately
under each dusting band an inclined board which presses up the apron from the
middle to one edge so that one half of one dusting band will be closely applied
to one half of the sheet. The other dusting band which moves in an opposite
direction has a similar inclined board under its portion of the apron but arranged
so that the band shall be closely applied to the other half of the sheet. Each
dusting band therefore cleans only one half of a sheet but I am enabled by the
above device to accomplish. the cleaning very efficiently and satisfactorily and also
avoid any risk of turning up the edges of the sheet.
In order that the travelling band or apron shall be properly stretched and to
prevent the same from moving from one side of the machine to the other when
running I provide a tension roller over which the band runs in addition to the
roller at each end of the band. This tension roller is capable of being adjusted so
that its axis makes different angles with the axes of the other two rollers and by
securing the same at a proper angle the band is not only maintained tight but is
caused to run straight without any tendency to shift along its rollers to one side or
the other of the machine. This almost invariably happens in ordinary machines
owing to the fact that when the axes of the two rollers aforementioned are parallel
one edge of the band is stretched more than the other edge thereof. By providing
a skew roller as hereinabove described I entirely obviate this difficulty.
My improvements are readily applied to existing machines and especially to
dusting off machines wherein travelling dusting bands are used.
Dated this 15th day of March 1895
W. P. THOMPSON & Co.,
31, High Holborn, W.C., Patent Agents for the Applicant.
An Improved Combined Bronzing and Dusting Off Machine.
I, CHARLES WRANGHAM WOODCOCK, 1ª Sumner Street, Southwark, in the
County of London, 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 :-
My invention relates to a combined bronzing and dusting off machine. The
object of my said invention is to construct improved machines by means of which
bronze or other powder may be applied to a sheet which has been printed with
suitable ink or varnish to which the powder adheres, and by means of which the
superfluous powder may be dusted off the same.
It has heretofore been the general practice to use two separate machines for

page_text: hese purposes one of which machines applies the powder and the other of which
usts off the superfluous powder from the sheet that is to say from those parts of
he sheets upon which nothing was printed.
According to my invention I combine these two machines and apply the powder
nd dust the sheet in one operation. I also improve the construction of both parts.
of the machine in various details as hereinafter set forth.
In the accompanying drawings:-
Figure 1 is a side elevation of a bronzing and dusting off machine constructed
according to my invention.
Figure 2 is an end elevation looking in the direction of the arrow in Figure 1
and
Figure 3 is a plan of the same.
Figure 4 is a cross section of the hopper on the line - Figure 3, drawn to an
enlarged scale.
The sheet of paper A to which the powder is to be applied is fed between two.
horizontal rolls B. C. above the upper one B of which is provided a ductor or
hopper D containing the powder which escapes through a slit in the bottom of the
said ductor direct to the upper surface of the said uppermost or bronzing roll..
The width of the slit in the bottom of the ductor is preferably capable of
adjustment according to the amount of bronze or powder required to be supplied.
to the sheet. One arrangement for this purpose is shewn very clearly in Figure 4.
The side D¹ of the ductor is fixed and extends to the top of the roll B the side D
of the ductor is pivoted as shewn at D³ Figure 3 and its distance from the roll B
can be regulated by means of a thumb-screw D' as shown. In Figure 4 I also
shew a device for shaking or tapping the ductor in order to prevent the bronze
from clogging the slit. This device comprises a rock-shaft D actuated by a.
pawl D and ratchet wheel D' secured to the end of the bronzing roll. The said
rock-shaft carries a series of tappets Ds which knock or hammer the movable
side D of the hopper when the shaft is rocked.
After leaving the bronzing roll the sheet passes between one or more pairs of
feed or pressure rolls E, F which tend to maintain the paper straight and also press.
the powder into the ink or varnish thereon. The pressure of these rolls may be
The sheet is then carried forward on an endless
adjusted by any suitable means.
travelling band or apron G carried by two rollers H, I one of which is on the main
shaft J. Above the band are placed one or more idle rolls K which are merely
driven by friction, and press the sheet on to the endless band with a gentle pressure.
While the sheet is on the endless band the superfluous bronze or other powder is
brushed or dusted off by one, two or more brushes arranged as hereinafter
explained. The sheet after leaving the dusting brushes is clear of powder except
where the same has adhered to the printed portions.
The dusting-off brushes I prefer to use have the form of endless bands L, L of
a piled fabric such as plush or the like sewn to leather or other strips. I provide
two such bands which are arranged above the apron and driven by bevel wheels L', L'
in a direction perpendicular to the direction of motion of the sheet off which the
5 powder is to be dusted. One of said bands travels in an opposite direction to the
other as shown by the arrows. Each dusting band is itself cleaned by being
drawn at some part of its travel past a cleaning brush M, rotating in bearing M¹.
I prevent these cleaning brushes from becoming clogged with powder off the
dusting bands by causing the hair or bristles thereof to pass through the teeth of a
0 suitable comb. By this means I ensure the dusting bands being maintained in a
clean condition and also I prevent the powder from being shaken into the air which
often happens with the ordinary dusting bands which become full of bronze dust in
a very short time. The dust brushed off by the bands aud brushes is caught in
suitable receptacles provided for the purpose.
55 In order to prevent the dusting bands L from catching the edge of the sheet of
paper I provide two rollers N, N' underneath the apron which have conical
portions as clearly shewn in the plan. The effect of each roller is to press up the

page_text: apron from the middle towards one edge so that one half of each dusting band is
closely applied to one half of the sheet. Each dusting band therefore dusts from
the middle to the side of a sheet and the two bands together dust the entire
surface. Instead of using conical rollers as shewn I sometimes provide inclined
boards under the apron for a similar purpose.
In order that the travelling apron G shall be properly stretched and to prevent
the same from moving from one side of the machine to the other when running
I provide a tension roller O over which the band runs in addition to the roller at
each end of the band. This tension roller has its bearings in slots O' so that it
can be adjusted and by securing the same at a proper angle the band is not only
maintained tight but is caused to run straight without any tendency to shift along
its rollers to one side or the other of the machine. This almost invariably happens
in ordinary machines owing to the fact that when the axes of the two rollers
aforementioned are parallel one edge of the band is stretched more than the other
edge thereof. By providing a skew roller as hereinabove described I entirely
obviate this difficulty.
I sometimes divide the ductor or hopper by means of partitions or I use a series
of separate boxes or small hoppers suitably supported on the top of the bronzing
roll in place of a single long hopper or ductor. By this arrangement I am enabled
to apply different coloured powders to different parts of the sheet in the same
operation. In order to avoid mixing the colours when the superfluous powders are
brushed off the sheet I use dusting bands the direction of motion of which is not
perpendicular to that of the sheet but is parallel therewith. The dusting bands
may be caused to move in either direction but when the face of the band which is
applied to the sheet moves in the same direction as the sheet the band must be
driven faster so as to brush the powder off the sheet at the end of the travelling
apron. I may however use dusting brushes having their axes parallel to the feed
rolls as shewn at P, P, in the drawing instead of bands as above described. The
receptacles for collecting the dust of these brushes are shewn at P1, P1.
My improvements are readily applied to existing machines and especially to
dusting off machines wherein travelling dusting bands are used.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In machines such as described the combination with the dusting bands or
brushes of cleaning brushes or the like, substantially as, and for the purpose,
specified.
2. In machines in which transverse dusting off bands are used the provision of
means whereby one half of the paper is inclined so as to be closely applied to one
or more of the bands the other half of the paper being similarly applied to the
other band or bands substantially as and for the purpose specified.
3. In a bronzing machine, a ductor or hopper with or without partitions for
enabling different varieties of bronze to be applied in one operation, and with or
without the tapping device, substantially as described.
4. A. combined bronzing and dusting-off machine substantially as described.
Dated this 16th day of December 1005
W. P. THOMPSON & Co.,
31, High Holborn, London, W.C., Patent Agents for the Applicant.