IMPROVEMENTS IN THE MANUFACTURE OF BOXES AND SIMILAR ARTICLES FROM PAPER PULP
Year: 1876

page_text: LETTERS PATENT to William Frederick Tindell, of 18, Essex Street, Strand, in
"
the County of Middlesex, Gentleman, for the Invention of IMPROVEMENTS IN
THE MANUFACTURE OF BOXES AND SIMILAR ARTICLES FROM PAPER PULP." A
communication from abroad by Seth Wheeler, of Albany, in the State of New
York, United States of America.
Sealed the 23rd September 1876, and dated the 28th March 1876.
PROVISIONAL SPECIFICATION left by the said William Frederick Tindell at
the Office of the Commissioners of Patents on the 28th March 1876.
WILLIAM FREDERICK TINDELL, of 18, Essex Street, Strand, in the County of
Middlesex, Gentleman. "IMPROVEMENTS IN THE MANUFACTURE OF BOXES AND
SIMILAR ARTICLES FROM PAPER PULP." A communication from abroad by Seth
Wheeler, of Albany, in the State of New York, United States of America.
This Invention primarily consists in forming boxes or other hollow articles from
any description of pulp in a closed vessel under pressure, produced by the admission
to said closed vessel of compressed air, gas, or steam, or by forcing into the vessel
water or pulp.
A convenient means of carrying the Invention into effect is as follows:-The
pulp is placed in a receiver or chamber supported upon suitable frame and provided
with cover.
This receiver also contains form carrier, which is carried by a hollow
pipe free to move up and down through stuffing box at bottom of chamber, and is
provided with tap or valve at bottom. The motion to form carrier and pipe is
communicated by lever or other convenient means, and the carrier is provided with
stripper for removing the articles after being compressed. The upper part of the
chamber is by pipe connection in communication with air or gas or other fluid
reservoir under pressure, the admission to pulp vessel being cut off or effected by.
tap or valve, the reservoir being supplied with compressed air or other fluid from
pump or other convenient means.
The operation is as follows:-The cover being removed from the pulp chamber,
which is, say, one half to two thirds filled with pulp, and the form elevated above
it, I commence by placing the perforated or permeable covering over the form. The
chamber is then closed, and air admitted to the chamber at any desired pressure

page_text: through the pipe at top of chamber. The form is now lowered into the pulp by
means of the pipe that supports it. When entirely submerged the valve in the
pipe is opened, and an instantaneous rush of pulp about the form takes place. The
form is then raised into the air space above, the rapid passage of which through
the newly-formed article removes much of the moisture. The supply of air is then
shut off, the chamber opened, and article removed. Thickness is regulated by
thickness of pulp, amount of pressure, and time that form is submerged.
In order to prevent the pulp from hanging on or adhering to the "stripper" I
place a "curb," consisting, say, of a ring of sheet metal, extending round the form,
but not over the top, the distance from the form being regulated as required. When
the article is raised out of the pulp the "curb" is full, but the rapid movement of
air through it deposits all the pulp upon the form.
Although it is preferable to have the air space over the pulp, nevertheless the
chamber may be wholly filled with pulp, in which case the articles require more
time to dry.
Where I employ the pulp as the compressing medium, the pulp chamber is then
preferably somewhat larger than when using air or other compressed fluid.
The aperture or pipe for the admission of pulp to chamber is preferably at the
lower part of same.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Frederick Tindell in the Great Seal Patent Office on the
28th September 1876.
WILLIAM FREDERICK TINDELL, of 18, Essex Street, Strand, in the County of
Middlesex, Gentleman. "IMPROVEMENTS IN THE MANUFACTURE OF BOXES AND
SIMILAR ARTICLES FROM PAPER PULP." A communication from abroad by Seth
Wheeler, of Albany, in the State of New York, United States of America.
This Invention refers to the forming of boxes or other hollow articles from any
description of pulp in a closed vessel under pressure produced by the admission to
said closed vessel of compressed air, or by forcing water or pulp into the vessel, all
substantially in and by the means herein-after set forth.
And in order that the said Invention may be properly understood I will proceed
to describe how the same may be carried into practical effect, reference being had
to the accompanying Sheet of Drawings and to the letters and figures marked
thereon, that is to say:-
Figure 1 illustrates in vertical section a suitable form of apparatus constructed
according to this Invention; Figure 2 is a sectional plan of part of the same
apparatus.
A represents a cylindrical or other shaped vessel closed by a tightly fitting cap a,
At the bottom the
and supported by legs a¹, or in any other convenient way.
vessel A is provided with a stuffing box B, through which a hollow stem or pipe C
is passed. The upper end of the said pipe C is provided with a hollow head D,
which is perforated at d and grooved round its outer circumference, as shewn more
particularly at Figures 4, 5, and 6, which are respectively outside elevation, plan,
and horizontal section of the form carrier D. The said grooves may be straight or
circular or of other suitable shape, and effecting a surface communication with the
said perforations and with the interior of the head D. These grooves are also
connected at their lower ends by a circular horizontal groove E of larger dimensions,
from which connection with the interior of the head D is made by perforations c.
Below the groove E the head D is provided with a step F, upon which a loose
collar H rests. The head D has a removable perforated covering G made of stiff
material, metal being preferred when the articles being made have vertical sides.
This covering is closely and finely perforated, so as to act on the pulp as a sieve.
The top of this covering G is a separate piece held in position by a shank G

page_text: which is inserted into the mould head D. The covering G is split at g² (see
Figure 3), so that it may be easily removed from the head D or out of the finished
box. The loose collar H covers the groove E, and extends some distance above it,
so as to prevent the pulp from having any access to it. It also serves as a stripper
to slip the box off the form or mould. The lower part of the pipe C is provided
with a stop cock c¹ and a fixed ring I, having horizontal journals i (see Figure 3),
with which a forked or other shaped lever J is connected for the purpose of
operating the mould head D.
For the admission of compressed air the vessel A is provided with an inlet a², to
which a pipe K is connected communicating with, say, an air reservoir L. The
reservoir may be supplied by a force pump M or any other suitable power
mechanism.
In certain cases the chamber may be supplied directly from the force pump, and
the air compressed within the cylinder A to a pressure of at least one atmosphere.
The cap G may be split, as shewn at Figure 3, or it may be made of one or
more pieces, according to the intricate nature and requirements of the different
patterns.
In the accompanying Drawings and description the simplest form of the In-
vention is shewn, but in the practical application of the Invention the pulp cylinder
may be a large tank or vat, and a number of forms or heads corresponding to tho
one shewn, only varying from it in shape, placed in this vat. For example, Figure 7
shews a duplex form carrier D, which has two inould heads, the interior of each of
which is placed in communication with the pipe C. Figure S, again, is a plan view
of four such mould heads arranged upon a carrier, and connected to the pipe C in a
manner similar to that shewn at Figure 7.
The top of the pulp vat or chamber may be arranged to be opened automatically,
so also may the cocks of the several forms be connected and opened and closed
automatically and at one operation, and all the forms or heads may be connected
and raised and lowered automatically; the articles moulded may also be lifted off
the forms automatically.
ول
The fluid power may be applied to a moving piston, so arranged within the pulp
chamber that the air within the chamber is compressed to the degree desired, and
the pulp by means of this compressed air forced against and shaped upon the forms
or "heads; or water and pulp may under high pressure be forced together into
the mould chamber, and by pressure the articles of pulp will be formed upon the
moulds, and when thus formed can be lifted out of the mould chamber and dried.
By this process the articles may be formed either on the exterior or interior of a
form or head.
In manufacturing articles according to this Invention in the manner here more
particularly shewn and described, the vessel A is first supplied with pulp, say, to
one half or two thirds of its capacity, the pulp being in a fluid or semi-fluid state.
The perforated forms having been placed upon the head D the chamber A is closed,
and the compressed air admitted thereto through the pipe K. The form carriers
and forms are then lowered by means of the lever J into the pulp, whereupon the
cock c¹ is opened. The pulp is immediately forced against the cap G of the head D,
and the pulp nearest thereto is drained of water through the grooves and per-
forations of the said cap, and finally collected in the hollow part of the head D,
from there to be conducted through the pipe C and the cock c¹ out of the machine.
When the pulp has formed around the cap in proper consistency and thickness the
mould head D is raised above the surface of the remaining pulp, and allowed to
remain until it is comparatively free from water and packed to the proper solidity
by the pressure of the surrounding air, the moisture being carried off rapidly
through the tube and its cock. The supply of pressure is shut off when the articles
are dry enough to be removed; the lid is then opened, and the cap G slipped off
the head D by means of the stripper H. The pulp box or other hollow articles
which has formed around the outside of the said parts is now freed from the cap G
and handed over to the finishers, who subject it to the treatment necessary for its

page_text: final appearance; or it may be subjected to a further drying and hardening process
before the cap G is removed, depending upon the shape of the article, finish, and
character.
Having now described the nature of the said Invention, and in what manner the
same is to be performed, I wish it to be clearly understood that I am aware that
applications for Patents have been made, and Patents have been granted for In-
ventions in connection with the manufacture of articles from pulp, in the Specifi-
cations of which references have been made to the application of fluid pressure to
the manufacture of hollow articles from such pulp, but all of these Inventions differ
substantially from this Invention. For example, some prior Specifications have
referred to the employment of a vacuum to consolidate the pulp upon a perforated
mould, but direct fluid pressure above that of the atmosphere is not alluded to; but
I do claim the combination of parts forming the improved apparatus for making
boxes and other hollow articles from pulp by means of fluid pressure, substantially
as herein-before described and set forth.
In witness whereof, I, the said William Frederick Tindell, have hereunto set
my hand and seal, this Twenty-eighth day of September, in the year of
our Lord One thousand eight hundred and seventy-six.
WM. F. TINDELL. (L.S.)