Cinpres Limited

Target Brands, Inc.

Peerless Cinpres Limited

Matthew Emmett Sayer

Kenneth Richard Crow

Robert D Peota

Mark T Ryan

David L Pruitt, Jr

Charles E Shell

A method of molding a shopping cart component includes providing a first subcomponent and then overmolding the shopping cart component as a second subcomponent about the first subcomponent. The first subcomponent acts as an obstacle to a plastic injection stream and to a gas injection stream during the overmolding of the second component to assist in defining a first hollow section of the shopping cart component adjacent the first subcomponent.

Method of molding a shopping cart

The production of an injection moulding of plastics material that includes introducing a supply of plastics material through one or more openings in a mould space, and introducing by way of at least one gas supply passage, a pressurized gas through a separate opening in the mould space into the plastics material within the mould space whereby the gas creates a gas containing cavity in the plastics material. An opening and closing of the gas supply passage is controlled by a valve which is opened by the pressurized gas with the valve featuring a valve port at the outlet end of the gas passage, and a movable valve member extending longitudinally of the gas passage for opening and closing the valve port. The valve member at least when in its extended or valve port open position, protrudes into the mould space and penetrates the plastics material to assist the gas in entering the plastics material. Also, with the valve member in its withdrawn or valve port closed position, plastics material is shut off from entering the end of the passage from the mould space.

Method and apparatus for producing an injection moulding of plastics

An injection molded plastic article is produced by introducing a stream of molten plastic material from an injection molding machine cylinder into an article forming mold space. Pressurized gas is supplied into the interior of the molten plastic material to form a gas containing cavity therein. The plastic material is then allowed to solidify and cool sufficiently so that the article can itself sustain the form dictated by the mold surface. The cavity is vented to reduce the pressure within the cavity to ambient pressure prior to opening of the mold. The step of venting the cavity is achieved by providing at least one position which is separate from the plastic inlet and the gas inlet a vent passage in the mold open at its inner end to a part of the interior of the mold at which the gas containing cavity is formed, and a retractable closure for opening and closing the vent passage at its inner end, maintaining the closure in its closed position during the forming of the article whereby the cavity wall is formed over the inner end of the vent passage and the closure therefor, and subsequently retracting the closure to allow the creation of a vent opening in the cavity wall in the area of the inner end of the vent passage through which vent opening gas from the cavity passes into the vent passage. Apparatus for carrying out the above process is also described.

Method and apparatus for injection moulding

Apparatus for producing an injection moulding of plastics material comprises means for introducing a supply of plastics material, passage means for communicating the supply means to a mould space, and means for introducing a pressurized gas into the plastics material filling the mould space whereby the gas creates a gas containing cavity in the plastics material and for thereafter relieving the gas pressure within the gas containing cavity before the mould is opened. The gas supply/pressure relieving means comprise valve means including a valve port opening directly into the mould space, for opening the gas filled cavity to the atmosphere, a valve member for closing the port, and means to supply pressurized gas to the mould while the valve member is in the port closing position to create the cavity and to maintain the valve port open to the cavity whereby, after a moulding operation has been finished, the supply of pressurized gas can be terminated and pressurized gas in the cavity in the moulding can be vented to atmosphere by opening the valve member.

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Marlow, United Kingdom

Matthew Emmett Sayer