Improvements in Sand Tables or Traps for Paper Making Machines.
Year: 1895

page_text: Date of Application, 11th Dec., 1895
Complete Specification Left, 9th Sept., 1896-Accepted, 10th Oct., 1896
PROVISIONAL SPECIFICATION.
Improvements in Sand Tables or Traps for Paper Making Machines.
I, JAMES HUNTER ANNANDALE, of Polton Paper Works, Polton, Midlothian,
Paper Manufacturer, do hereby declare the nature of this invention to be as
follows:-
This invention has for its object the provision of improved means to facilitate
the deposition or precipitation of sand and other particles of sedimentary foreign
matter from paper pulp on its passage from the beating engine to the strainer or
before it passes on to the wire of a paper making machine.
In the art of paper-making stationary sand tables or boxes are at present used for
this purpose and are provided with cross slats or bars to intercept the sedimentary
matter which settles in these tables or boxes, but it is found in practice that a
large percentage of such foreign matter is held in suspension by the pulp while
it remains in a clotted or flocculent state, and this is deposited on the strainer
plates or on to the "wire of the paper making machine when owing to the
vibratory motion imparted to the wire the pulp is brought to a more uniform
consistency by disintegration of the clotted masses. The result is that the side
of the paper adjacent to the wire contains the heavy sedimentary matter whilst
the upper surface contains the lighter loose floating particles.
"
According to my invention I overcome this objection by passing the pulp
through a sand table or box to which a vibratory or jigging motion is imparted
in a transverse or other direction by any mechanical means such as by the use of
levers or toggles operated by a rapidly rotating crank or eccentric which causes
the breaking up of the clotted masses of the pulp before it passes on to the wire
or at an earlier stage of the manufacture and ensures the deposition of the sand and
heavy foreign matter as well as the more intimate mixing and better distribution
of the component parts of the pulp.
This vibrating or oscillating sand table is provided with the usual intercepting
cross bars or with cross channels to receive the sedimentary deposit and it is also by
preference fitted with longitudinal division plates or boards which serve to better
transmit the vibratory motion of the sides of the box to the mass of pulp flowing
along the middle parts of the sand table. At or near the outlet end a cross board
or plate dips into the. pulp and forms a trap to skim and intercept floating foreign
matter.
In lieu of vibrating or oscillating the sand table as a whole the longitudinal
division boards alone may be vibrated or oscillated.
Dated this 10th day of December 1895.

page_text: Improvements in Sand Tables or Traps Ior Paper making machines.
I, JAMES HUNTER ANNANDALE, of Polton Paper Works, Polton, Midlothian,
Paper Manufacturer, 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 :-
This invention has for its object the provision of improved means to facilitate the
deposition or precipitation of sand and other particles of sedimentary foreign
matter from paper pulp on its passage from the beating engine to the strainer or
before it passes on to the wire of a paper making machine.
In the art of paper-making, stationary sand tables or boxes are at present used
for this purpose and are provided with cross slats or bars to intercept the
sedimentary matter which settles in these tables or boxes, but it is found in practice
that a large percentage of such foreign matter is held in suspension by the pulp
while it remains in a clotted or flocculent state, and this is deposited on the strainer
plates or on to the "wire" of the paper making machine when, owing to the
vibratory motion imparted to the wire, the pulp is brought to a more uniformn
consistency by disintegration of the clotted masses. The result is that the side of
the paper adjacent to the wire contains the heavy sedimentary matter whilst the
upper surface contains the lighter loose floating particles.
According to my invention I overcome this objection by passing the pulp through
a sand table or box to which a vibratory or jigging motion is imparted in a
transverse or other direction by any mechanical means such as by the use of levers
or toggles operated by a rapidly rotating crank or eccentric which causes the
breaking up of the clotted masses of the pulp before it passes on to the wire or at
an earlier stage of the manufacture and ensures the deposition of the sand and
heavy foreign matter as well as the more intimate mixing and better distribution of
the component parts of the pulp.
The invention is illustrated in the accompanying drawings in which Figure 1 is a
longitudinal vertical section, Figure 2 a cross section and Figure 3 a plan of a
sand table showing one arrangement of devices for imparting vibratory motion
to it.
The improved sand table comprises the usual trough or box A into which the
paper pulp is led by an inlet over the part A' and thence flows over the table A
towards the outlet end A'.. The table or the movable part of it is supported upon
an articulated framing composed of cross bars or beams B carried by vertical
rods B¹ jointed to them and to supports at B2 on the floor. To the jointed
supporting frame B, B', or to brackets B' on the underside of the box A, are jointed
the ends of links or connecting rods C whose opposite ends are attached to cranks D
or to eccentrics or cams on a rapidly rotating shaft E driven by a belt pulley F or
by other means. By the rotation of the shaft E oscillating or vibratory movement
is imparted to the articulated frame and to the sand table supported on it, whereby
the pulp passing through the trough A is kept in a state of tremor and the
sedimentary matter in it is shaken down or precipitated on the table.
The mechanism for imparting oscillating movement to the sand table may be
varied in many ways as may also be the direction of motion. The jogging or
vibratory motion may be applied at both ends or only at one end of the table a
pivot being in the latter case provided at the opposite end so that the jogging
motion may be gradually reduced as the pulp flows on.
Instead of being supported from below, the table may be suspended from above
and the vibratory motion either imparted to the table or to the frame on which it
is suspended provided that such motion is transmitted to the table or to such part
of it as will communicate the desired shake or tremor to the pulp.

page_text: The vibrating or oscillating sand table is provided with the usual intercepting
cross bars F1, or with cross channels, to receive the sedimentary deposit and it is
also by preference fitted with longitudinal division plates or boards & which serve
to better transmit the vibratory motion of the sides of the box to the mass of pulp
flowing along the middle parts of the sand table. At or near the outlet end a
cross board or plate H dips into the pulp and forms a trap to skim and intercept
floating foreign matter.
In lieu of vibrating or oscillating the sand table as a whole the longitudinal
division boards G or other part may alone be vibrated or oscillated.
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. A vibrating sand table constructed substantially as described.
2. The combination with a sand table of means for imparting vibratory or like
movement to it or to part of its structure.
Dated this 8th day of Santambor 1906
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62 St. Vincent Street, Glasgow, Agent for the Applicant.