Mold apparatus for molding a weighing funnel that has a large diameter central segment, and a hole at each end that is smaller than the central segment. A 2-part core is used, the two parts together forming the size and shape of the article to be molded, and to remove the core from the molded article, the parts are withdrawn individually through a hole at the end of the article.

FIELD OF THE INVENTION
 The invention resides in the general field of injection molds, for molding
 plastics.
 SUMMARY OF THE PRESENT INVENTION
 The mold of the invention includes a core construction for molding a shape
 that could not be molded by previously known molds.
 The article to be molded is hollow, with opposite end openings smaller than
 the interior. In previous molds and core constructions, it was not
 possible to mold such an article in a single piece. It is desired to mold
 it as a single piece, and in a one-stop operation, to reduce costs of
 manufacture.
 A broad object of the present invention is to provide injection mold/core
 construction having the following features and advantages. The molded
 article is hollow, or tubular, with small openings at its ends. The core
 is made up of a pair of parts fitted together, but moveable relative to
 each other in endwise direction. One of the core parts can be individually
 removed first, and then the other core part removed.
 The core parts arc held in position in the cavity block in the mold, in
 which they are positioned.
 As a consequence of the immediately forgoing feature, the molded article
 can be molded, and removed from the mold, in a minimum of time, thereby
 reducing costs of manufacture, and the molded article is in its final
 intended shape, eliminating the necessity for cutting away parts of the
 molded article, or for trimming it or otherwise treating it after it is
 removed from the mold.
 The core parts are so positioned in the molding cavity that they form one
 end of the cavity, and thereby form one of the end openings of the molded
 article and the surrounding defining edges thereof.
 The device is of such character, in position and function, that as used in
 an injection mold, injection parts can be positioned at any location in
 the mold cavity.

DETAILED DESCRIPTION OF THE DRAWINGS
 For convenience in consideration of the disclosure, a description of the
 article to be molded is given first, followed by a description of the mold
 core itself, and the mold in which it is positioned.
 The molded article is indicated at 20, the article being tubular, hollow,
 and having open ends. It is oriented according to a central longitudinal
 axis 21. The article includes a main body segment 22 of large dimensions,
 merging into a conical segment 24, the latter then merging into a reduced
 pouring neck 26 of small dimension. The body segment 22 has a major
 portion 28, nearly cylindrical in shape, but having a flat bottom surface
 30 (see also FIG. 3) also referred to as a resting surface.
 The article is shown in FIGS. 1, 3, 4 as resting on its side, on its flat
 surface 30, but it assumes also an upright position, in a pouring or
 emptying position, as in FIG. 2.
 The pouring neck 26 has an open end 32, and the body has an opening 34 at
 its other end. The pouring neck 26 may have an end surface 27
 perpendicular to the axis 21 as shown in solid lines (FIG. 4), or disposed
 at an oblique angle thereto as shown in dot-dash line 29. The opening 34
 lies in a plane indicated by the line 36 (FIGS. 4, 5) which is inclined
 relative to the central longitudinal axis 21 at an angle 35 which is
 preferably about 50.degree. but this dimension is not critical. The plane
 36 cuts through the cylindrical portion of the segment 22 at the top of
 the latter, but at the bottom it cuts through at a position that may be
 referred to as an end surface of the article, producing a turned up edge
 38 forming a low confining wall for holding the contents in the article
 when in the position of FIG. 1.
 Heretofore, such an article was formed by first molding it with a
 continuous or closed end surface, as at the right hand end in FIG. 4, and
 then cutting through the article at the position of the plane 36 (FIG. 4)
 which involved an operation separate from and in addition to the actual
 molding step.
 In the use of the article, it is placed on a supporting surface 40 (FIG. 1)
 which in the present instance represents a weighing scale, with the bottom
 surface 30 on the surface 40, and then the materials or ingredients for a
 prescription are inserted through the open end 34 into the article. Such
 materials may be liquid or solid, and in either case, the confining wall
 38 prevents those ingredients from falling or running out of the article
 through the opening 34, in handling it. The scale 40 determines the
 correct amount to be inserted in the article, and then in the continued
 use thereof, the article is fitted and inserted into the flask or any
 narrow neck item 39 (FIG. 2) and the contents thereby emptied into the
 flask. In this step, a liquid may be sprayed into the article, through the
 large open end 34, for washing the materials therefrom into the flask.
 The molded article 20 is known as a weighing tunnel and is preferably
 transparent and made of plastic. Among the plastics available, the
 following have been proven practical, polypropylene, polyethylene, and
 polystyrene.
 Polyethylene is advantageous because it is highly anti-static.
 It is also found practical to make the article of reusable borosilicate
 glass. Plastic is preferred, being custom in such use thereof and as
 recommended by safety organizations. Glass is considered less sate because
 of its fragility.
 The one-piece nature of the article produces an extremely great advantage
 in cost of manufacture, but a difficulty arises related directly to this
 feature: the end openings must be of lesser dimension than the main
 internal dimension in order to make it usable as a weighing tunnel, while
 preventing the accidental loss of the ingredients. The core of the present
 invention makes it possible to make the article of one-piece character.
 The core is made up of multiple pieces (2) that are sufficiently small to
 be removed through the open end 34 of the article in the direction of the
 longitudinal axis 21, that is, to withdraw each individually in
 longitudinal direction. The central large segment 22 of the article, is of
 the greatest transverse dimension, as indicated by the arrow 41 of FIG. 4.
 In comparison with that dimension, attention is directed to the arrow 44
 indicating the effective dimension of the opening 34, i.e. perpendicular
 to the axis. It is pointed out that the opening 32 is of course also
 smaller than the dimension 41. As used herein references may be made to
 radial dimensions, as in a fully cylindrical shape, notwithstanding the
 flat bottom surface 30.
 Summarizing, each part of the core is sufficiently small to be withdrawn
 from the molded article through the large opening 34. Attention is
 directed particularly to FIGS. 1 and 4 showing the confining wall 38
 extending above the bottom surface 30 to confine the materials in the
 article. The pouring neck is of course above the flat bottom, in that
 position of the article.
 Reference is now made to the mold for forming the article, as shown in
 FIGS. 8-10. FIG. 8 shows a mold 42 in diagrammatic form, having a central
 vertical axis 43. It includes a stationary frame 45 which itself includes
 a top fixed plate 46 having injection ports 47 therethrough. Blocks 48,
 49, 50 are mounted for vertical sliding movements on the frame. In FIG. 9,
 the block 48 is shown to nave a main part 52, and insert parts 54 the
 latter being slidable toward and from each other (FIG. 8), carrying cavity
 blocks 56, 57 with internal cavities 58, 59. To produce this sliding
 movement, the mold frame is provided with diagonal guide rods 61, and the
 insert parts 54 of the block 48 have holes receiving those diagonal guide
 rods. Consequently, in response to upward sliding movement of the block
 48, due to the inclination of the rods and holes, the guide rods guide the
 cavity blocks 56-57 inwardly into engagement with each other to closed
 position shown in FIG. 10, and into engagement with the top plate 46.
 The cavities 58, 59 then form a single cavity 63 except for the bottom. In
 such upper, or closed, position of the cavity blocks 56, 57, the injection
 ports 47 lead into the cavity 63 as referred to again more specifically
 hereinbelow.
 The core is indicated in its entirety at 65 (FIG. 6), being made up of two
 opposed parts 66, 68 with flat sides 70, 71 (see also FIG. 7) fitted
 together. The mold parts are provided with bottom base elements 73, 74,
 and upper elements 76, 77. The entire mold, when the parts are assembled,
 are positioned on opposite sides of a plane 79 which, upon completion of
 the molding step, contains the longitudinal axis 21 (FIG. 4). The core
 parts 66, 68 together are shaped to form the final molded article, the
 part 66 being the longer, forming that portion of the article that is
 uppermost, (FIG. 1), while the part 68 is shorter and has an inturned
 bottom element 78. The core parts are positioned in the cavity 63 as
 described below.
 When the core parts are fitted together in operable position as shown in
 FIGS. 6 and 7, the parts 76, 77 form a junction with the respective bottom
 elements 73, 74 along a line 80. The bottom parts 73, 74 extend laterally
 or radially outwardly beyond the parts 76, 77, to form a continuous
 surface along the line 80 which itself forms the bottom surface 81 of the
 cavity (FIG. 10).
 The core parts are provided with cooperating tongue and groove elements 81'
 securely holding them together while enabling them to be moved
 longitudinally relative to each other.
 The core parts 66, 68 are secured to the sliding blocks 49, 50,
 respectively, as indicated at 82, 83 (FIG. 8). The core parts together
 extend through a hole 84 in the block 48 with the core part 66 also
 extended through a hole 85 in the block 49. In this position, the upper
 parts 76, 77 extend up into the space between the cavity blocks 56, 57, as
 the slidable mold blocks 48, 49, 50 are raised by a suitable means of
 known kind indicated by the arrows 86. This raising motion moves the
 cavity blocks 56, 57 inwardly toward each other, as explained above, and
 upwardly until they engage the top member 46.
 It will be appreciated that the upper elements 76, 77 together, are of less
 transverse dimension than final cavity, resulting from the cavities 58, 59
 fitting together, to form the article cavity 63 with which the injection
 ports 47 register. The molding material, plastic, is then injected into
 the cavity through those ports and upon hardening, forms the final molded
 article.
 In such position of the core, as indicated above, the top surface 81 of the
 bottom elements of the core defines the edge of the large opening 34 (FIG.
 1) and it will be noted that the portion or element 78, (FIG. 7) as now
 shown in FIG. 10, forms the inturned element 38 (FIG. 3) of the molded
 article.
 After the molding step just described, and the molded article has set, the
 blocks 48, 49, 50 (FIG. 11) are lowered to the positions shown in FIG. 11.
 This movement of the block 48, separates the cavity blocks 56, 57.
 Thereafter the block 50 is lowered, drawing the core part 66 downwardly
 out of the molded article.
 Thereafter the molded article is flexed to align the other core part, 68,
 with the hole 34, which releases the molded article and enables it to be
 removed from the mold.