Improvements in the Construction of Tile Press Dies or Plates for the Production of Undercut Recesses in the Manufacture of Tiles.
Year: 1897

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 11 of the Patents, &c. Act, 1883) as required by
the decision of the Comptroller General of the 12th day of July 1898.
Date of Application, 4th Dec., 1897-Accepted, 12th Mar., 1898
Improvements in the Construction of Tile Press Dies or Plates for the
Production of Undercut Recesses in the Manufacture of Tiles.
We, WILLIAM BURTON, of Clifton Junction, near Manchester, in the County of
Lancaster, Earthenware Manufacturer, and JOSEPH BURTON, of Clifton Junction
aforesaid, Potter's Manager, 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: -
Our invention consists of an addition to the lower die or bottom plate of an
ordinary press for the manufacture of tiles from clay dust of a mechanical arrange-
ment consisting of suitable pieces of metal to produce the undercut recesses
required (and which pieces of metal are hereinafter referred to as 'the said
teeth"). The said teeth are made longer than the distance between the upper and
lower surfaces of the bottom die and one end can be made to project from either
of such surfaces. The said teeth are also provided with a projecting shoulder or
rim. The said teeth are fixed and work in a slot or groove made in the lower die
which slot is made wider where it receives the projecting shoulder of the said
teeth and sufficient space is provided to receive a spring for acting upon the
projecting shoulder of the said teeth and to admit of the proper working of the
said teeth.
When the bottom die is not in use and therefore quite free from any pressure
the springs are arranged so that by acting against the lower die and the shoulder
of the said teeth the lower ends of the said teeth are caused to project below the
under surface of the bottom die the upper ends being on a level with the upper
surface of the die but when the bottom die is drawn by the spindle (with the usual
weight attached to the same) against the press bed in the proper position for the
making of a tile in the usual way the weight of the spindle is brought to bear
upon the projecting lower ends of the said teeth and causes the shoulder of the
same to compress the springs and so causes the upper end of the said teeth to
project a sufficient distance above the upper surface of the die to produce the
undercut recesses and when the bottom die is lifted from the press bed after a tile
has been made to allow the tile to be removed from the press the springs are
at once liberated and automatically withdraw the teeth from the undercut so
that the tile can be removed without injury to the undercut.
As an alternative method of working our invention it may be mentioned that
the springs referred to may be made of sufficient strength to prevent the said
teeth from being fixed in position for the formation of the undercut recesses until
the pressure of the upper die is applied which would then by compressing the
springs force the said teeth into the body of the tile in the direction of the slots or
grooves and when such pressure was removed the springs would automatically,

page_text: withdraw the said teeth leaving undercut recesses in the tile which could then
be removed from the press in the usual way without any liability to injure the
undercut recesses so produced.
The nature of such invention and the manner in which it may be practically
applied is more particularly shown in the accompanying drawings of which the
following is an explanation.
Figure 1. is a cross sectional elevation of the said lower die or bottom plate
made according to our said invention and fitted with grooves or slots and the said
teeth AA" when held against the press bed by the spindle in position to form
or mould a tile.
The projecting ends of the said teeth "AA" form the undercut recesses "BB"
in the tile.
It may be pointed out that when in use the lower die is fitted into a die box
and is held by the spindle and its attachments during the moulding of a tile
against the press bed so that the said teeth "A A" must be occupying the position
shown in Figure I. during the pressing or moulding of the tile (the springs S S
being compressed). These springs are fitted as shown in such a manner as to act
on projecting shoulders or rims on the said teeth in a direction parallel to that
in which the said teeth move so as to work to the best advantage and with
certainty.
After the tile has been pressed or moulded the lower die is raised by means
of the spindle Sp (as in the ordinary method of working) in order to remove the
tile from the die box and it will be seen that as soon as the lower die is raised
from the press bed the said teeth A A are free to move downwards sufficiently to
withdraw their projecting ends from the undercut recesses formed in the tile and
that the springs S S which were compressed during the moulding will now
withdraw the said teeth from the undercut recesses in the position required before
the tile is removed as shown in Figure II.
After removing 'the tile the bottom die is again lowered and the lower ends of
the said teeth A. A coming in contact with the press bed the said teeth will be
'forced by the weight of the die and the spindle (with the usual weight attached
to the same) into the position shewn in Figure I. The springs being again com-
pressed and the bottom die and the said teeth being in a position for the moulding
of another tile with undercut recesses.
With regard to the alternative method it may be pointed out that the springs a
may be made so strong and be so arranged that they are not fully compressed as
in Figure I. by the weight of the die and the spindle holding the same against
the press bed until the pressure required to mould the tile is applied by the
upper die.
In this case the said teeth A A. are only forced into position after the die box
has been filled with the "clay dust" from which the tile is made and consequently
the edge of the undercut recess will be harder and more solid.
Figure III. is a plan of the aforesaid lower die or bottom plate in same position
as Figure I in which A A represent the said teeth and B B the position of the
undercut recesses which may be of any suitable length or shape.
It will be seen that the said teeth may be shaped so as to form any pattern of
undercut recesses so long as the grooves or stops in the lower die in which the
teeth move are shaped accordingly.
The said teeth might also be withdrawn from the undercut by hand (instead
of being withdrawn automatically by means of springs) after the lower die had
been raised above the die box but the automatic method is preferred and is con-
sidered to work in a more satisfactory manner.
It should be pointed out that the lower die is made up of several pieces so
constructed and arranged that the teeth, A A, may be readily fixed in position
in the lower die.
One method of so constructing the lower die is shown in Figs. I and II. It
will be seen that there are two pieces of the lower die marked C C, CC, which
5

page_text: are fastened to the main portion of the die by means of the screwed studs D D,
DD, and that when these said pièces C C, C C, are removed, the teeth A A,
may then be placed in position as shown in Fig. II, and the pieces C C, C C,
replaced and fixed in position by means of the studs D D, D D.
The said pieces C C, C C, may conveniently run from end to end of the lower,
die, or they may be made of exactly the same length as the teeth A A.
-
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we wish it to be understood
that we are aware that it has been proposed in the manufacture of undercut tiles
to form the under-cut recesses therein by means of one or more loose pieces which
are adapted to slide in inclined slots in the back or bottom part of the die, and
which are withdrawn from the under-cut recesses by means of springs after the
tile has been moulded, and we lay no general claim to such means, but confine
ourselves to the arrangements herein before described and illustrated in which
the loose pieces or teeth extend from the top to the bottom of the die-plate and
we declare that what we claim is:-
I. The improvements in the automatic mechanical arrangements or apparatus
for the production of undercut recesses in the pressing or moulding of tiles
substantially as described set forth and illustrated in the accompanying drawings.
II. The application to the production of undercut recesses in the pressing of
tiles from clay dust of the mechanical arrangements or apparatus substantially
before described.
Dated this Thind dow of December 1897