New or Improved Means or Apparatus for Moulding Cores Employed in Casting Tubes or Hollow Articles with Internal Ribs or Projections.
Year: 1889

page_text: Date of Application, 27th June, 1889
Complete Specification Left, 27th Mar., 1890-Accepted, 3rd May, 1890
PROVISIONAL SPECIFICATION.
New or Improved Means or Apparatus for Moulding Cores Employed
in Casting Tubes or Hollow Articles with Internal Ribs or
Projections.
I, JAMES YATE JOHNSON, of 47. Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, do hereby declare the nature of this invention, which has been com-
municated to me from abroad by Jean Pierre Serve of rue des Servettes, Givors,
Rhone, in the Republic of France, Manufacturer, to be as follows:-
This Invention relates to a new or improved moulding apparatus or core box to be
employed in the moulding of cores employed in the manufacture of hollow articles of
cast metal presenting internal projections such for example as tubes of circular oval
elliptic or other form in section provided with inwardly projecting longitudinal ribs
of any suitable number and any suitable depth or thickness such ribs extending
either the entire length of the tube or being interrupted at intervals or otherwise
according to requirements.
An apparatus constructed according to this invention for moulding cores with
longitudinal recesses for use in casting internally ribbed tubes is composed mainly
of a species of mould formed by two or more metallic pieces or segments of a
cylinder which when united form a case or cylinder whose internal diameter is
equal to the diameter of the tube to be produced the length of the said cylinder
being somewhat greater than that of the tube. These two pieces or segments are
provided with longitudinal slots or openings corresponding in number to the ribs
to be formed in the tubo and extending to within a short distance of the ends of the
segments. These slots or openings are provided for the reception of bars or plates
forming moveable ribs or webs which are capable of sliding radially and parallel
with the axis of the mould in these slots and project into the interior of the mould
the part thus projecting being of the same shape and dimensions as the ribs or webs
to be formed on the tube.
The segments must be made of sufficient thickness to enable these longitudinal
ribs or webs to be firmly supported and guided in the slots.
It will be understood that if these ribs or webs representing the internal ribs or
webs or on the cast tube were permanently or immoveably fixed in position on the
semi cylindrical segments of the core box or mould the convergent position of these
ribs or webs would cause them to engage with the sand or material of the core and
thus prevent the said segments from being separated in order to remove them from
the core after the latter has been moulded. This difficulty is overcome in apparatus
constructed according to this Invention by causing the ribs or webs in the core
moulding box to slide radially in the sides of the mould after the sand forming the
core has been rammed in the said ribs or webs can be moved radially or drawn back
to a sufficient extent to bring their inner edges flush with the inner surfaces of the
segments of the cylindrical mould and thus enable the said segments or parts of the
mould to be readily separated without injury to the core.
In order to facilitate the movements of the bars representing the ribs the segments
of the mould are provided at two or more points in their length with collars or flanges
cast on or otherwise secured to the segments. These collars or flanges are provided
opposite each slot or opening in the segment with a recess of the same width as the
slot and of the same depth as the distance to which the ribs or webs project into the
interior of the mould.
By these means the ribs or webs are enabled to move back parallel with themselves
to a distance equal to the distance to which they projected in the interior of the mould

page_text: so as to be completely disengaged from the sand core as herein before explained the
extent of their outward movement being limited by the dimensions of the openings or
recesses in the collars or flanges.
These moveable ribs or webs may be provided at the part where they pass through
the collars or otherwise with handles or suitable means for moving them parallel with
themselves in their respective slots. In order to securely connect and retain in the
proper relative position the parts or segments composing the mould two or more
hoops are employed as hereinafter explained. These hoops are made in two parts
hinged together and capable of being connected by bolts or otherwise at their free
ends and are placed over the mould box at suitable distances apart.
In using a mould box or apparatus according to this invention the segments of the
cylinder are placed vertically or on end and are firmly connected together by means
of two of the said hinged hoops one being placed at the upper end and one at the
lower end beyond the extremities of the moveable ribs or webs so as not to interfere
with the movements of the latter. By means of their handles these ribs or webs are
then pushed radially inwards towards the centre of the mould the distance to which
they are caused to project in the interior being regulated or limited by suitable stops
or projections on the backs or ends of the said ribs or webs after which other jointed
hoops are placed on the mould so as to bear against the outer edges of the moveable
ribs or webs and render it impossible for them to slip outwards. The mould being
thus prepared and closed the hollow metallic rod or frame forming the axis of the
core is placed in position and the sand is rammed in, in the usual manner.
This operation being terminated the two jointed hoops lastly put on are removed
and after loosening the moveable ribs by a few taps with a haminer they are pulled
radially outwards until their outer edges bear against the bottoms of the recesses in
the flanges on the mould. The moveable webs are then known to be drawn back flush
with the inner surfaces of the segments and it is simply necessary to remove the
jointed hoops at the ends of the cylinder in order to separate the seguents and remove
the core which prevents a series of longitudinal radial depressions or recesses corre-
sponding to the form of the ribs or webs to be produced in the interior of the tube.
The form and arrangement of the parts such as the means for moving guiding and
retaining the segments and the moveable webs for example may be modified according
to circumstances and the hoops employed for binding the segments together may
be either separate from or jointed or hinged to the parts of the mould.
hoops at the ends may be dispensed with altogether the parts of the mould being
provided with clamping devices or lugs and pins or bolts connected together so as
to advance and retire forming a mechanical arrangement enabling the parts of the
mould to be quickly moved as required. The moveable webs can be arranged to
be worked in a similar manner.
The
If required the mould can be removed from the core by sliding out the webs
longitudinally end wise. In this case the mould is likewise formed in segments
preferably two connected together by hinged hoops but the opening or recesses in
these segments do not pass completely through the sides and extend to the upper
end. These recesses or grooves are of dovetailed or other equivalent form corre-
sponding exactly with the form in transverse section of the backs of the moveable webs.
In working with this arrangement the moveable webs are slipped in endwise from
the top end of the mould their backs sliding in the dovetailed grooves so that they
are firmly retained in position whilst the sand is being rammed in. This operation
being concluded the moveable webs are carefully drawn out endwise at the upper end
of the mould which is then free to be opened for the removal of the core.
The mould may be composed of any suitable number of sections or segments
according to the nature and dimensions of the tube or hollow article to be cast upon
the core made by means of this apparatus..
Dated this 27th day of June 1880.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.

page_text: Figure a transverse section.
Figure 4 a plan of the aforesaid core box, and
Figure 5 is a transverse section of a tube having internal ribs, the latter being easily
obtained when the improved core box is employed.
The apparatus comprises a kind of mould formed of two parts or half cylinders A A
of metal, whose internal diameter is equal to the internal diameter of the tube to be
cast and whose length is somewhat greater than that of the tube.
The above mentioned two parts are provided with longitudinal slots, which are equal
in number to the number of ribs to be formed in the tube and as shewn in Figures 1 and 2,
extend to within a short distance from the extremities of the said parts. These slots
are designed to receive metallic plates or bars B, the length and thickness of which
are equal to the length and width of the slots, and which when in their place, project
into the interior of the mould a distance equal to the height of the ribs to be provided
in the tube, the form of the projecting parts of these plates or bars corresponding
exactly to that of the aforesaid ribs. The thickness of the curved parts A of the said
mould must be sufficient to enable the plates or bars B, to be firmly maintained in the
slots which receive them. These plates or bars are movable in the slots, and are held
therein as hereinafter described.
It will be readily understood that if the plates or bars B were permanently fixed in
the mould, their converging position would prevent the separation of the said two parts
and the removal of the moulded core of sand. In order to obviate this difficulty, the
plates or bars B are arranged to slide freely in the slots which receive them, so that
when the sand has been rammed into the mould they can be moved back a sufficient
distance to bring their inner edges flush with the inner surfaces of the mould or box,
in which position the two parts of the latter can be readily separated and the core can
be removed.
In order to enable the displacement of the plates or bars B, to be easily effected, the
curved parts A of the mould are provided at two points of their length with two collars
or flanges C, cast or otherwise permanently secured upon the parts A. These collars
or flanges have opposite each slot in the mould an internal recess of the same width as
the slot and of the same depth, as the distance to which the plates or bars B, project
into the interior of the mould. By these means each of the plates or bars B can be
moved back in such a manner that all its positions will be parallel to each other. As

page_text: the extent of this movement is equal to the distance which the plates or bars project
into the interior of the mould, the said plates or bars can be completely disengaged
from the core of sand as above stated, their receding movement being limited by the
full parts of the collars or flanges C. as clearly shown in Figure 3.
For the purpose of enabling the plates or bars to be easily displaced in their slots
they are provided, either at the points where they traverse, the recessed collars or
flanges C. or at any other suitable points of their length, with metallic rods or spindles
connected to handles D, with the aid of which they can be caused to advance or recede
in their slots, so that all their positions will be parallel to each other.
To hold the two parts A A of the mould firmly together, use can be made of two
pairs of collars E E and FF which are represented in Figures 1 and 2, and the respective
objects of which will hereinafter be explained.
When the core hox is to be used, the two parts A. A of the mould are placed
vertically and forciby held against each other by means of the two collars E. E. care being
taken to place the latter in proximity to the upper and lower ends of the mould-that
is to say, beyond the extremities of the plates or bars B-so as not to interfere with
the movements of the latter. With the aid of the rods or spindles D the plates are
caused to enter the interior of the mould, the degree of the forward movement being
limited by means of studs or projections on the back or on the ends of the said plates
or bars. By the two collars F. F which are next placed on the mould, the firmness
of the connection of the parts A A is further increased, and as the said collars are
applied exactly upon the backs of the plates or bars the latter will be held in their
place, being prevented from receding. The mould having thus been closed, a hollow
metallic rod or lantern, designed to form the axis of the core is introduced and the
sand is rammed into the mould in the ordinary manner. This operation being
terminated, the two intermediate collars F F are removed, and after having caused the
plates or bars B to vibrate by a few taps with a hammer, they are successively moved
back by means of these rods or spindles D, so as to cause the backs of the plates or bars
to bear against the bottoms of the recesses in the exterior collars C of the mould.
Having thus made sure that the said plates or bars have been completely moved back
in the recesses of the parts A A, it is sufficient to remove the exterior collars E E in
order to open the mould and remove therefrom the core of sand which it contains.
It will be understood that I do not limit myself to the precise forms and arrange-
ments above described and represented in the accompanying drawings for displacing
guiding and retaining the two parts of the mould and the plates. Thus for example,
the collars E E and F F, can be either independent or mounted by hinges upon the
mould and the outer collars E. E can be dispensed with, the two parts A A, of the
mould being provided with lugs connected by bolts so that they can be caused to
approach and recede from each other. This mechanical device will enable the two parts
of this mould to be rapidly moved at will. The plates or bars B can be moved in a
similar manner.
It will be understood that the separation of the mould and core can also be effected
by completely removing the plates or bars B through the top part or end of the mould.
In this case the mould is also made in two parts A. A. connected by means of hinged
collars FF; but the said parts instead of having slots formed in them are provided
with grooves which extend to the upper end of the mould and present in transverse
section a dovetail shape corresponding exactly to the transverse section of the backs
of the plates or bars B. Under these conditions it is sufficient to introduce the plates
or bars B into the above mentioned dovetail grooves from the top end of the mould,
in order to be firmly held in place while the sand is rammed into the mould. This
operation being concluded the said plates or bars are carefully drawn out through
the upper end of the mould which can then be opened for the removal of the
core.
The mould can be formed of any number of parts or sections A A. as deemed
preferable and according to the dimensions and the form of the hollow casting for
which the core is to be used

page_text: Having now particularly described and ascertained the nature of the said Inven
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A mould consisting of two or more parts provided with longitudinal slots equal
in number to the number of internal ribs which the hollow casting shall possess. plates
or bars movable in the slots and presenting the form and dimensions of the said ribs,
the said plates or bars being designed to form the depressions in the core which
correspond to the ribs in the hollow casting to be produced and rods or spindles on
the plates or bars for drawing them back to permit the opening of the mould when
the core is to be removed.
2. A mould consisting of two or more parts provided with longitudinal slots equal
in number to the number of internal ribs, which the hollow casting shall possess, plates
or bars movable in the slots for forming the depressions in the core which correspond
to the ribs in the hollow casting to be produced rods or spindles for drawing the plates
or bars back, and collars encircling the mould and provided with recesses coinciding
with the slots in the mould to receive the plates or bars when the latter are moved
back substantially as herein before described.
3. A mould consisting of two or more parts provided with longitudinal slots equal
in number to the number of internal ribs which the hollow casting shall possess, plates
or bars movable in the slots for forming the depressions in the core which correspond
to the ribs in the hollow casting to be produced, rods or spindles for drawing the
plates or bars back, and removable collars encircling the mould for holding the plates
or bars against receding movements, substantially as herein before described.
Dated this 27th day of March 1890.
J. H. JOHNSON & Co.,
Agents.