Improvements in and Apparatus for Moulding Earthenware Electric Switches, Ceiling Roses, Bell Pushes, and the like, and Forming Screw Threads thereon.
Year: 1892

page_text: Date of Application, 30th Sept., 1892-Accepted, 22nd Apr., 1893
COMPLETE
SPECIFICATION.
Improvements in and Apparatus for Moulding Earthenware Electric
Switches, Ceiling Roses, Bell Pushes, and the like, and Forming
Screw Threads thereon.
I, JOSEPH MEIR of 13, Stanley Street, Burslem, Staffordshire, Potter, do
hereby declare the nature of my said 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 refers to the formation of earthenware electric switches, ceiling
roses and the like in a simpler and more expeditious manner than heretofore and to
machinery or apparatus therefor.
In carrying out my invention I first of all form blanks or blocks of the desired
article, moulded in plaster moulds or "jollied" approximately to the size required
and semi-dried. The blanks or blocks are then introduced into a fly press fitted
with specially formed dies, as hereinafter more particularly described, for pressing
the article to its final form and forming the screw thread thereon, and in order to
remove the article so pressed into shape I provide convenience for the ready
removal and transference of the dies from the fly press to a "whirler” or its
equivalent when the moulded switch is unscrewed.
And in order that this my said invention may be more readily understood and
carried into practical effect I have hereunto annexed a sheet of drawings illustrative
of my improvements and will now proceed to describe the same with the assistance
of the various figures and letters of reference marked thereon.
Fig. 1 is a general view of a fly press shewn fitted with my improved moulding
dies suitable for moulding the covers of electric switches.
Fig. 2 is a vertical section of my improved moulding dies and moulding box as
used in the formation of the bases of electric switches.
I will first describe my invention as applied to the formation of an electric
switch cover for which the dies are prepared as in Fig. 2, where A is the upper die
(seen separately in Fig. 4) attached to the plunger B of the fly press by means of
a dovetail sliding joint C, so constructed that when the plunger Bis raised the
die A can be readily detached from the plunger B by the simple act of drawing it
forward.
The die is screwed at A¹ and corresponds with the form it is desired to give to
the inside of the switch cover.
D is the lower die resting upon the block E operated as hereinafter described
by the rod F and foot lever Fi but it must be understood that in the formation of
the switch cover the block E is not operated, but forms simply a rest or support for
the bottom die D.
In the formation of the switch cover it will be understood that the die A is
raised out of the mould as seen in Fig. 1.
The blank prepared, as hereinbefore described, and which should have an excess
of substance as is well understood by potters, is then introduced on to or into the
lower die D and the plunger being brought down the plastic or semi-plastic clay
is moulded or shaped into the form illustrated by the solid shading in Fig. 2 and
particularly the screw thread A' is well and truly formed therein.
The screw press is now released and the plunger B rises, bringing with it the
newly formed cover which is now attached to the upper die A by the screw thread
formed in it and to facilitate this the bottom die D is formed with a vent D' filled
in during the moulding operation by the substance of the block E so that in with-
drawing the moulded cover the lower die D is either left in the moulding box or is
very readily detached as the plunger rises.

page_text: On the plunger B reaching the upper part of its stroke and the moulded cover
being now well clear of the moulding box as seen in Fig. 1, I remove the upper
die A by drawing it forward as hereinbefore described and thus I have the upper
die detached with the moulded cover screwed thereon as seen in Fig. 4.
I now transfer the die A and moulded cover to a whirler (see Fig. 5) inverting
it and in the act of so doing the taper plug A2 (seen dotted in Fig. 2 and separately
in Fig. 6) falls out and allows free access of air between the head of the die and
the moulded cover.
The whirler is constructed with a recess which approximately fits the dovetail C
and acting as a key to rotate the die A.
I now set in motion the whirler and carefully grip the moulded cover and I have
found that by this means I can safely and expeditiously unscrew it without injuring
the screw thread formed therein.
The base of the switch is formed in a similar manner by a series of dies corre-
sponding in form and represented in section in Fig. 3, where G is a screw ring to
form the thread on the base and resting loosely on the stand H and supported on
block E.
The solid shaded portion represents the switch base under formation but the
upper die (a) in rising after the pressing operation leaves the moulded base in the
moulding box.
By the action of the foot lever F I raise the block E, stand H and ring G and
moulded base out of the moulding box and I then transfer the ring G and the base
to the whirler (see Fig. 5) which has been prepared to receive it having two
projecting pins corresponding to two recesses I in the ring G and thus I rotate the
ring G on the whirler and by gripping the base carefully I unscrew it from the
ring as described with reference to Fig. 2 and without the complicated mechanism
heretofore in use.
Although I have described my invention as applied to the formation of electric
switch covers it will be readily understood that other articles and shapes could be
made by varying the dies accordingly.
Having thus 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.
1st. Forming earthenware electric switches, ceiling roses, bell pushes and the
like and making the screw threads thereon by pressing in a press fitted with dies
and detaching the pressed work by means of a whirler or its equivalent substantially
as set forth.
2nd. The improved dies for forming the covers of earthenware electric switches
ceiling roses, bell pushes and the like consisting of a plunger B detachable upper
die A moveable plug A2 lower die D block E and moulding box all mounted and
operating substantially as shewn and described.
3rd. The detachable die A carrying the moulded cover and adapted to be applied
to a revolving instrument such as a whirler to unscrew the cover substantially as
shown and described.
4th. The improved dies for forming the bases of earthenware electric switches
ceiling roses bell pushes and the like consisting of an upper die A ring G and
block E all mounted and operating substantially as shewn and described.
Dated this 29th day of September 1892.
JOHN G. WILSON,
Agent for the Applicant.