GB2088834A

GB2088834A - Granulate Container for a Synthetic Plastic Material Injection Moulding Machine Provided with a Viewing Window

Info

Publication number: GB2088834A
Application number: GB8137064A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-12-09
Filing date: 1981-12-09
Publication date: 1982-06-16
Also published as: DE3046298A1; GB2088834B; DE3046298C2; CH652643A5; JPS57120424A; JPH0135733B2; ATA523781A; NL8105403A; FR2495539B1; FR2495539A1; IT8125404A0; IT1139592B; AT375873B

Abstract

A granulate container produced from sheet metal for a synthetic plastic material injection moulding machine, has a viewing window of high-polymer material which is releasably secured in an aperture in a funnel-shaped container portion, the window being elongate and made by injection moulding and being situated with its axis of symmetry parallel to a generatrix of the container, the window comprises a peripheral groove which is bounded by a rim portion 45a internally and by a rim portion 45b externally, which latter rim portion is reduced at its relatively wide upper end moulded part, with the exception of a portion bounded by slots 46, to a base ridge 45c which is flush with the groove bottom, and wherein the rim 23a of the container wall which engages substantially in a single plane into the groove is offset relatively to the adjacent container wall by way of a continuous deformation zone of substantially the same depth. <IMAGE>

Description

SPECIFICATION Granulate Container of a Synthetic Plastic Material Injection Moulding Machine, Provided with a Viewing Window The invention relates to a granulate container produced from sheet metal for a synthetic plastic material injection moulding machine, provided with an inspection or viewing window of highpolymer material which is releasably secured in a funnel-shaped container part in the region of an aperture in the container wall.

In the usual granulate containers of this kind the viewing windows are punchings obtained from flat material which are clamped by means of a synthetic plastic material frame to that rim of the container wall which defines the aperture therein, with the use of screwed connections. The production of such viewing windows involves a relatively considerable outlay on assembly.

Moreover the unevenness resulting at the inner container wall from the screwed connections make it difficult to empty the container or change the synthetic plastic material, since granulate residues remain sticking to the region of the unevenness.

The invention has as its object to develop a granulate container of the type initially specified further in such a manner as to obtain substantially better conditions for rational series production of viewing windows, to allow easy assembly of such windows, and to avoid having on the inner wall of the granulate container in the region of the viewing window any unevenness which would make the emptying of the container more difficult to any notable extent.

According to the invention this object is achieved in that an injection moulded part made of synthetic plastic material, which is elongated in form, forms the viewing window, and is situated with its axis of symmetry parallel to a generatrix of the container, is provided with a peripheral groove bounded internally by a rim portion and externally by a rim portion, said rim portion being reduced in a relatively wide portion of the injection moulded part except for a portion bounded by slots to a base ridge flush with the groove bottom, and that the container wall rim, engaging approximately in a single place in the groove, is offset relatively to the neighbouring container wall by way of a continuous deformation zone of approximately the same depth.

With such a construction the injection moulded part forming the window can be releasably connected to the container wall substantially without the use of tools.

The invention will be explained hereinafter with reference to a constructional example, with the help of the accompanying drawings, wherein:~ Fig. 1 shows a longitudinal section through the granulate container arranged on the injection unit of a synthetic plastic material injection moulding machine; Fig. 2 shows a fragmentary view from the exterior, on a larger scale, of the container wall in the region of the viewing window; Fig. 3 shows a section taken on the line Ill-Ill of Fig. 2 (injection moulded part only partly in section); Fig. 4 shows a section taken on the line lV-lV of Fig. 2; and Fig. 5 shows a section taken on the line V-V of Fig. 2.

In the illustrated constructional example the granulate container 23 is formed of an upper part made from sheet steel and with container wall 23c, and a funnel-shaped base part 25. The latter is a funnel-shaped shaped part produced by machining. The part produced from sheet steel is also made funnel-shaped at its lower portion. Its inner funnel wall merges almost continuously into the inner funnel-shaped wall of the base part 25.

The container 23 is accommodated by a support part 26. As Fig. 1 shows, the lower funnel-shaped portion of the sheet steel container part ends in a cylindrical portion 23d which is inwardly flanged.

This cylindrical portion 23dips clamped in between the base part 25 and the support part 26. The viewing window is formed of an elongated synthetic plastic material injection moulded part 45. The latter is so inserted in the container wall 23c in the funnel-shaped portion thereof that its plane of symmetry extends parallel to a generatrix e-e. The injection moulded part 45 has a peripheral groove 47. This groove is bounded internally by a rim portion 45a and externally by a rim portion 45b.

In an upper, relatively wide portion of the injection moulded part 45, of circular geometric basic form, the rim portion 45b is reduced to a base ridge 45c flush with the groove bottom 47a.

Consequently, in the region of this base ridge 45c the rim 23a of the container wall bounding the aperture 24 for the viewing window is not engaged behind by the injection moulded part.

But this does not apply to a small portion y which is situated in the axis of symmetry of the injection moulded part and which is set off from the base ridge 45c by slots 46. In this portion y the rim portion 45b is not reduced to a base bead or ridge 45c but constructed as in the narrower portion a of the injection moulded part. Thus in the portion y a rim portion 45b of the injection moulded part engages behind the rim 23a of the wall. The container wall rim 23a engaging into the groove 47 in a plane d-d is offset inwardly, i.e. towards the granulate filling, relatively to the adjacent container wall 23c via a continuous deformation zone 23b of the same depthzthroughout. In a viewing region x the injection moulded part 45 has a plane parallel pane region 45d.The latter comprises at the inner side a plane surface extending over this pane region 45d and over the rim portion 45a. This surface is situated in the plane of the internal surface of the pane region 45d. The outer surface of the pane region 45d, is in a sunken situation in the part 45. In its narrower portion a, the injection moulded part 45 comprises rim portions 45a, 45h disposed parallel to one another. The free end 48 of this narrower portion a has a radius r. The narrow portion a of the injection moulded part is about 6 times as long as the broad portion b.The depth z of the deformation zone 23b corresponds substantially to the maximum thickness of the injection moulded part 45 in the region of its rim portions 45a, 45b The injection moulded part 45 does not anywhere project radially beyond the wall 23c of the granulate container 23. The rim portion 45a is rounded off towards the rim 23a, which extends in shape-locking manner into the groove 47. The injection moulded part is inserted without tools as follows into the aperture 24: it is pushed downwardly in such manner with the free rounded end of its narrower portion from the interior of the container 23 at the border line g between the narrower and the wider portions of the injection moulded part that its peripheral groove 47 runs into the parallel rims 23a of the container wall.The rim portions 45a, 45b thereat engage over the rims 23a and guide the injection moulded part in this movement, which presupposes a limited elastic deformation of the part 45 towards the interior of the container. When the end 48 of the injection moulded part abuts with its groove bottom 47a on the end face of the rim 23a, the injection moulded part at its largerdiameter portion b can spring into the upper portion of the opening 24. To obtain a secured snug fit it is necessary to bend the rim portion 45b slightly downwardly in the portion y, so that it arrives on the outer side of the rim 23a, so that the rim portion (45b) can lock in this portion y into the rim 23a.In the locked position the rim portion 45b, acting as locking tongue, engages behind the rim 23a so that the injection moulded part is fitted immovably and in sealing-tight manner in the aperture 24 of the container wall. The rounded encircling rim portion 45a lies securely on the rim 23a of the container wall, so that sharp angles and gaps from which synthetic plastic material could be removed only with difficulty are obviated.

The sheet steel wall 23c in the funnel-shaped lower portion of the container is subjected to strong internal stresses due to the deformation of the sheet steel portion when it is rolled up to form a funnel-shaped container. After the aperture 24 is punched out, these stresses cause an immediate outward swing or springing of the wall regions bounding the aperture 24. To this extent the inward offsetting of the rim 23a achieved by means of a deformed wall zone over the depth z serves a double purpose: on the one hand it results in stabilisation of the container wall in the rim region bounding the punching. On the other hand it facilitates the introduction and extraction of the injection moulded part into and from the aperture, since because of the offsetting of the rim 23a in the inward direction the reversible bending of the injection moulded part which is required can be less considerable. When the injection moulded part is taken out, the rim portion 45b in the region y is pressed downwards and the injection moulded part is bent outwards at its upper portion, so that when pulled Jut it can slide upwards on the inner side of the container wall.

Claims

1. Granulate container (container) produced from sheet metal for a synthetic plastic material injection moulding machine, having a viewing window of high-polymer material which is releasably secured in a funnel-shaped container portion in the region of an aperture in the container wall, characterised in that an elongated part made from synthetic plastic material by injection moulding, which forms the viewing window and is situated with its axis of symmetry parallel to a generatrix of the container, comprises a peripheral groove which is bounded by a rim portion internally and by a rim portion externally, which latter rim portion is reduced at a relatively wide portion of the injection moulded part, with the exception of a portion bounded by slots, to a base ridge which is flush with the groove bottom, and that the rim of the container wall which engages substantially in a single plane into the groove is offset relatively to the adjacent container wall by way of a continuous deformation zone of substantially the same depth.

2. Granulate container according to claim 1, characterised in that the rim is inwardly offset.

3. Granulate container according to claim 1 or 2, characterised in that the injection moulded part comprises, in the viewing region, a plane parallel pane region and comprises, internally, a substantially plane surface which extends over this pane region and the rim portion and which is situated in the plane of the inner surface of the pane region.

4. Granulate container according to claim 3, characterised in that the external surface of the pane region is in a sunken situation in the injection moulded part.

5. Granulate container according to any one of the preceding claims, characterised in that the injection moulded part in its narrower portion comprises parallel-arranged rim portions and has a circular plan in its relatively wide portion.

6. Granulate container according to any one of the preceding claims, characterised in that the free end of the narrower portion of the injection moulded part has a radius.

7. Granulate container according to any one of the preceding claims, characterised in that the narrow portion is about 6 times as long as the wide portion.

8. Granulate container according to any one of the preceding claims, characterised in that the depth of the deformation zone corresponds to substantially the maximum thickness of the injection moulded part in the region of its rim portions.

9. Granulate container according to any one of the preceding claims, characterised in that the rim portion is situated on the axis of symmetry of the injection moulded part.

10. Granulate container according to any one of the preceding claims 2 to 7, characterised in that the injection moulded part does not project anywhere radially beyond the wall of the granulate container.

11. Granulate container according to any one of the preceding claims, characterised in that the rim engages positively in the groove and the rim portions is rounded off towards the rim.

12. A granulate container substantially as herein described with reference to the accompanying drawings.