GB2116594A - Machine installations - Google Patents

Abstract

A clean room environment for manufacturing moulded plastics bodies, especially containers for the pharmaceutical industry, comprises at least two separate closed environments (3, 5 Fig. 1 not shown) separated by a wall 4, one of them being kept at elevated pressure by filtered air. The wall has an opening in it and a moulding machine 1 for making the containers protrudes through the opening and is sealed into it but is able to move into and out of the opening, for example on rails, with the services to the machine being connected to it in the one environment 3, whilst the bodies produced emerge from that part of the machine which, in use, is in the environment 5 which is at an elevated pressure. <IMAGE>

Description

SPECIFICATION Machine installations This invention relates to the layout of so-called 'clean room' areas in manufacturing industry.

In the manufacture of certain chemical products, in particular ethical and pharmaceutical products and also of electronic or scientific products on a microscopic scale, absolute cleanliness is essential. It is therefore well known to manufacture such products in an environment which is kept at a higher air pressure than the surroundings and is entered only through air-lock type double doors. Carefully filtered air is fed to the area.

However it is no good producing goods under clean conditions unless the containers in which those goods are to be marketed are equally clean.

It is therefore desirable, for example, to manufacture the containers destined for pharmaceuticals under exceptionally clean conditions. However the normal plastics injection moulding machines on which such containers are produced, and the normal workshops in which such machines are installed, are by no means conducive to maintaining the required conditions.

The aim of the invention is to provide a machine shop environment in which machines of a basically orthodox construction can be employed under 'clean-room' conditions without detracting from the normal needs for servicing, toolchanging, maintenance and so on, that such machines require.

According to the invention a factory layout for moulding machines for producing moulded bodies of plastics, in particular injection-moulded or injection/blow-moulded plastics containers comprises at least two separate closed environments separated by a wall, the one environment being maintained under elevated pressure by filtered air and isolated frorn outside atmosphere and from the other environment by double-door air-locks, and the wall has at least one opening in it through which a production machine is movable on rails, with sealing means around the opening to seal the machine into the opening.

Preferably there is a shutter that can close the opening off completely when the machine is withdrawn from the clean environment, and it may be arranged that this shutter can be put into position before the machine is withdrawn, so that there is little or no loss of air.

In a preferred arrangement the machine, when in operation, projects partially through the opening so that the part of it which is producing the goods is in the clean environment, whilst as much as possible is still kept outside in the other, less clean environment. In a typicai moulding machine the necessary hydraulic rams and clamps cannot avoid being contaminated with lubricating oil. If they are kept as far as possible outside the clean area, whilst the actual moulds are within it, contamination of the goods being produced is avoided.

The necessary connections to the machine for oil, water and electrical supplies are made wholly within the less clean environment, and are preferably flexible so that they do not need to be disconnected when the machine is withdrawn into that environment for tool-changing or maintenance.

The invention will now be further explained by way of example with reference to the accompanying drawings, in which: Figure 1 and 2 are respectively a sectional elevation and a plan view of a building layout according to the invention with a central machine room area flanked by two clean environment areas and containing a totai of four moulding machines.

Figure 3 is an isometric section through the building, and Figure 4 is a detail showing the shutters over the wall between the areas.

The machines used in this example are commercially available injection-moulding machines manufactured either by Fahr Bucher or by Maurer, since these have the right disposition and shape to suit the layout according to the invention and the Fahr-Bucher machine is guaranteed to keep the clean platen area free of oil. Each such machine, shown at 1, is mounted on rails 2 to move between the operative position shown, in which one end of the machine projects from a machine room 3 through a wall 4 into a 'clean-air' area 5, and a retracted 'maintenance' position in which it is wholly within the machine room 3.

The apertures in the walls 4 necessary to allow the moulding machines to pass through are equipped with flexible seals 6 that engage around the casings of the machines to minimise loss of air during operation of the machines. The moulds are preferably of the runnerless type, to avoid problems due to the pressure difference.

It will be understood that the platens and tools of the machines are at those ends of the machines which, in the operative position, are in the clean area, whilst the rams, supplies and so on remain in the machine room.

At each end of the building are ante-rooms 7 which can serve as cloakrooms and workshops and one of which communicates with the machine room 3 through single doors 8, whilst both communicate with the two clean-air areas 5 through double doors 9 forming air-locke. In a known manner, the two areas 5 are kept at slightly above-atmospheric pressure by a supply of filtered air.

The apertures in the wall 4 are provided with hinged hoods, of which one is shown at 10 in Figure 1 in an intermediate position. They are also shown in Figure 4. When the machines are in use these hoods are swung up out of the way, but before a machine is withdrawn into the machine shop for maintenance or tool-changing the hood is lowered to form a seal.

The services to each machine, for example of electricity, oil, compressed air and cooling water are preferably connected wholly within the machine shop area, and through flexible leads, for example from overhead connections, as indicated at 11 in Figure 1, so that they do not have to be broken when the machine is moved along the rails 2. There are also flexible connections 12 (Figure 3) to waste ducts in the floor of the machine room.

The feed of raw plastics to the machines can be from overhead hoppers shown at 1 3.

Claims (7)

1. A factory installation for moulding machines for producing moulded bodies of plastics under "clean room" conditions comprising at least two separate closed environments separated by a wall, the one environment being maintained under elevated pressure by filtered air and isolated from outside atmosphere and from the other environment by double-door air locks, and the wall having in it at least one opening through which a machine for producing moulded bodies is movable, with means around the opening to seal the machine into the openings.

2. An installation according to claim 1 in which the machine is movable linearly on rails.

3. An installation according to claim 1 or claim 2 in which the machine is a machine for producing moulded containers.

4. An installation according to any one of claims 1 to 3 in which there is a shutter or hood capable of closing and sealing the opening when the machine is withdrawn from the opening.

5. An installation according to any one of claims 1 to 4 in which the machine is connected to oil, water and electrical services within the said other environment through flexible connections that allow the movement of the machine in the opening.

6. An installation according to any one of claims 1 to 5 in which there are at least two machines and in which there are two of the firstmentioned environments on opposite sides of the said other environment, and correspondingly two of the said walls.

7. A factory installation for moulding machines for producing moulded bodies of plastics under "clean room" conditions, substantially as described with reference to the accompanying drawings.