WO2000061351A1

WO2000061351A1 - C-press

Info

Publication number: WO2000061351A1
Application number: PCT/SG1999/000031
Authority: WO
Inventors: Hans Lothar Berghoff
Original assignee: Hongguan Technologies (S) Pte Ltd.
Priority date: 1999-04-09
Filing date: 1999-04-09
Publication date: 2000-10-19
Also published as: AU3738999A

Abstract

An injection moulding unit (1) including: a first mould component (6) mounted in relation to a body (2) of the unit; a second mould component arranged for linear motion relative to the first mould component, between a retracted position in which the components are in spaced relation, to a closed position in which the components are closed about a moulding location, for injection moulding therebetween, wherein the second mould component is supported from a drive device (8) which is coupled between the second mould component and an arm (5) of the unit, opposite the first mould part, such that, in the retracted position, no supporting or guiding structure for the second mould component is present between the parts so as to thereby provide free access to the moulding location. The body of the unit is preferably 'C'-shaped and includes a main portion (3) and the mould components are located laterally thereof, with the first mould component being mounted laterally of a base portion (4) of the main portion and the arm projecting laterally from an upper end of the main portion to position the second mould component in alignment with the first mould component.

Description

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THE CLAIMS:

1. An injection moulding unit including: a first mould component mounted in relation to a body of the unit; a second mould component arranged for linear motion relative to the first mould component, between a_t'retracted position in which the components are in spaced relation, to a closed position in which the components are closed about a moulding location, for injection moulding therebetween, wherein the second mould component is supported from a drive device which is coupled between the second mould component and an arm of the unit, opposite the first mould part, such that, in the retracted position, no supporting or guiding structure for the second mould component is presentilbet een the components so as to thereby provide free access to the moulding location.

2. An injection moulding unit as claimed in claim 1 , wherein the body of the unit includes a main portion and the mould components are located laterally thereof, with the first mould component being mounted laterally of a base portion of the main portion and the arm projecting laterally from an upper end of the main portion to position the second mould component in alignment with the fust mould component. 0

3. An injecuon moulding unit as claimed in claim 2, wherein the body of the unit is "C"- shaped.

4 An injection moulding unit as claimed in any one of claims 1 or 3, wherein a cleaning 5 device is coupled to the body of the unit and adapted to extend between the components, when in the retracted position, for cleaning thereof.

5. An injection moulding unit as claimed in any one of claims 1 to 4 , wherein the drive device is a hydropneurnatic cylinder mounted in the arm and d e second mould component is 30 coupled to a ree endithereof - 7

6. An injection moulding unit as claimed in any one of claims 1 to 5, wherein the mould components are arranged for relative movement in a vertical direction.

C-PRESS

Fi l of the Invention

The invention concerns an injection moulding unit, preferably for the injection-moulding of a plastic casing around an IC chip.

Rackpround of the Invention

Injection moulding is achieved either by injecting thermoplastic material into a mould or by placing thermosetting moulding powders within the mould and subjecting the powders to heat, whilst applying compaction force to components of the mould.

A known form of unit for injection moulding includes guide rails, which extend between the components of the mould, to allow one of the components to move relative to the other component between a closed condition and an opened condition where an injection moulded article can be removed [therefrom. Such a unit is conventionally arranged so that the relative movement of the components occurs in a horizontal plane. In the case where the unit is used to injection mould around a part such as an integrated circuit or the like to form an IC chip with a plastic casing, the part will need separate support structure to hold it in place at a moulding location between the components of the mould both prior to and during the moulding process. The support structure may, for example, be in the form of a stamped metal sheet formed integrally with the IC chip.

5 A disadvantage of the unit is that the guide rails restrict the space available for manipulation and insertion of the part between the mould components. The need for support structure further exacerbates the problem. The support structure itself may also be damaged during application of the compaction force to the mould components in the event a thermoset moulding procedure is '.adopted Furthermore it is necessary to clean the components of the 0 mould afterevery injecuon process using cleaning devices, for example rotating brushes, and - 2 -

the guide ways also make the approach of the cleaning devices difficult.

Therefore it is the object of the invention, to create an injection-moulding unit of the aforementioned type, in which access between the opened components of the mould is less restricted.

Summary of the Invention

In accordance with the invention, there is provided an injection moulding unit including: a first mould component mounted in relation to a body of the unit; a second mould component arranged for linear motion relative to the first mould component, between a: retracted position in which the components are in spaced relation, to a closed position in which the components are closed about a moulding location, for injection moulding therebetween, wherein the second mould component is supported from a drive device which is coupled between the second mould component and an arm of the unit, opposite the first mould part, such that, in the retracted position, no supporting or guiding structure for the second mould component is present between the components, so as to thereby provide free access to the moulding location. 0

Preferably, the body of the unit includes a. main portion and the mould components are located laterally thereof, with the first mould component being mounted laterally of a base portion of the main portion and the arm projecting laterally from an upper end of the main portion to position the second mould component in ahgnment with the first mould component. 5

Preferably, the body of the unit is "C" -shaped.

Preferably, a cleaning device is coupled to the body of the unit and adapted to extend between the components, when in the retracted position, for cleaning thereof. 30 3 -

Preferably, the drive device is a hydropneumatic cylinder mounted in the arm and the second mould component is coupled to a free end thereof.

Preferably, the mould components are arranged for relative movement in a vertical direction.

The C-shaped or possibly U-shaped design of the body of the injection moulding unit makes it possible to feed objects into the mould without impediment from the front or from one of the sides. Furthermore, it is also possible to move cleaning devices, e.g. rotating cleaning brushes, into and between the opened components of the mould from the front-or from one of the sides.

Brief Description of the Drawings

The invention is described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Figure 1 is a side view of the injection moulding unit; and

Figure 2 is a side view of the unit with a thermoplastics injection cylinder.

Detailed Description of a Preferred Embodiment 0

An injecuon moulding lunit 1 is shown in Figure 1 as including a body 2 formed with a main portion 3 and a laterally extending base portion 4 and arm 5. The base portion 4 supports a first mould component 6 and houses a transfer unit 7. The arm 5 has a pneumatic cylinder 8 provided therein foci linearly driving a second mould component 9 toward and away from 5 the component 6. Theϋcylinder 8 Ls preferably a hydropneumatic cylinder which is both cost effective and environmentally clean to operate. The component 9 is mounted to a free end 10 of the cylinder 8 so that no supporting or guiding structure is present between the mould components 6, 9 when positioned in the reuacted position shown. As such free access is provided between the moulds to allow a part to be placed therebetween, at a moulding 30 location, for capture between the components 6, 9 and subsequent injection moulding. The - A

free access also allows a cleaning device 11 to be extended from the main portion of the body to between the components 6, 9 for cleaning. In order to injection mould about a part, the part is firstly placed between the components, at the injection location, and a predetermined amount of material is then dispensed from a magazine 12 onto the component 6, in a manner not shown. The cylinder 8 may then be energised to advance the component 9 into a closed position about the component 6. A compaction force is then applied for the moulding process and, upon completion of the injection process, the component 9 may be withdrawn and the moulded part simply removed without obstruction from, for example, guide rails which are present in a conventional injection moulding-unit.

As such, integrated circuits and the like may be readily inserted from the side into the space between the opened components of the mould for the formation of an IC chip with a plastic casing. The unit is also preferably arranged such that the mould components are moved relative to one another ;in a vertical direction. As such, an object which needs to be moulded therearound may be -simply placed on the mould component 6 and no support structure external to the mould is needed to keep the object properly positioned. Furthermore movable ejectors may be arranged within the unit for the parts of the mould, which eject moulded object preform after the opening of the mould.

0 At its front end the brush unit may be provided with a gripping device, which takes a tablet from one of the magazines 15 and inserts it into the cylinder 11 for the next injection process.

The unit 1 may also be provided with a thermoplastics injection cylinder 20, as shown in Figure 2 where like parts are denoted with like reference numerals. The cylinder 20 is 5 coupled to a hopper 21 which stores thermoplastic material. In use of the unit 1 , the mould components 6, 9 are advanced into a closed position and a charge of material from the hopper 21 is heated and then.isquirted from the cylinder 20 directly into the mould component 6 to effect thermoplastic injection moulding. The unit otherwise operates m a manner similar to that described with reference to Figure 1. 30 The unit 1 has been described by way of non-limiting example only and many modifications and variations may be made thereto without departing from the spirit and scope of the invention as hereinbefore described.