Abstract: A cylindrical mixing chamber opens into a subsequent cylindrical quieting chamber at an acute angle alpha against its direction of outflow to avoid spattering during the output of a plastic mixture formed of a reactive plastic components from a mixing apparatus.

Abstract: A mixing head for a high velocity reaction injection apparatus for mixing and dispensing two or more liquid components. The mixing head includes a mixing chamber with two or more inlets for the separate components and an outlet for dispensing the mixed components, and an injection housing for injecting each component through a corresponding inlet. Component flow is directed through a flow accelerating passage in the injection housing prior to injection into the mixing chamber, for imparting a pressure drop in the component on the downstream side of the passage, and means are provided for selectively blocking the inlets for terminating the dispensing of the mixed components and thereby increasing the component pressure in the injection housing downstream of the passage.

Abstract: Apparatus for high pressure impingement mixing includes a mixing chamber and aftermixer chamber located on opposite sides of, and perpendicular to, a transfer dispense chamber. Two or more reactive components are injected into the mixing chamber. The resultant mixture is directed across the transfer dispense chamber into the aftermixer chamber, and from the aftermixer chamber back into the transfer dispense chamber and around the crossing mixture to the outlet of the transfer dispense mixer for dispensing. Each chamber includes a plunger which is actuated sequentially to interrupt mixing and clean the respective chamber. The device provides effective and intimate mixing of the reactive components and dispenses a stable emulsion so that the device can be used in applications presently suitable only for low pressure mixing devices. It may also be used in existing high pressure applications but without the need for conventional aftermixer devices and gating systems disposed in the forming molds.

Abstract: A mixing head for a high velocity reaction injection apparatus for mixing and dispensing two or more liquid components. The mixing head includes a mixing chamber with two or more inlets for the separate components and an outlet for dispensing the mixed components, and an injection housing for injecting each component through a corresponding inlet. Component flow is directed through a flow accelerating passage in the injection housing prior to injection into the mixing chamber, for imparting a pressure drop in the component on the downstream side of the passage, and means are provided for selectively blocking the inlets for terminating the dispensing of the mixed components and thereby increasing the component pressure in the injection housing downstream of the passage.

Abstract: A high pressure injection mixing head for mixing and ejecting plastic materials consisting of more than one component. The mixing apparatus includes at least two mixing assemblies connected at their outlet ports to a transfer cylinder of a larger diameter. The components are being mixed in the mixing assemblies and then transferred into the transfer cylinder from which the mixture is injected into a mold. The mixing chambers of the mixing assemblies and the cavity of the transfer cylinder are automatically purged when the mixing head ejects material. An entry port for additional material may be located on the transfer cylinder.

Abstract: Method and apparatus for preparing multi-component plastic materials wherein at least one of the components is compounded with admixed solid materials or is highly viscous, the various components are continuously recycled and are metered separately by associated continuously operating feed pumps, and a mixing operation is effected in a mixing chamber served by a control piston. In the circuit for the compounded or viscous component a transmitter device is connected in a position downstream of the respective continuously operating feed pump and upstream of the associated mixing chamber inlet port. This transmitter device operates in a manner similar to a piston pump and increases the delivery pressure of the compounded or viscous component upon discharge into the mixing chamber whereby the operation of the transmitter is operatively coupled to the operation of the control piston at the mixing chamber. The component circuit may furthermore include a filling pump and a check valve.

Abstract: A mixing and proportioning apparatus for multi-component plastics materials such as polyurethane comprises a number of tanks, a mixing chamber and a separate pipe connecting each tank to the mixing chamber. The tanks are provided with pressurizing means for causing the components to flow through the pipes and each pipe is provided with a metering mechanism to control the flow of the component through it. The metering mechanisms of the different pipes are all positively coupled to each other so that the rates of flow of the components through the pipes are all kept in constant proportions.

Abstract: A mixing device for mixing together multi-component plastics materials, for example polyurethane, comprises a mixing chamber into which supply ducts for the components lead and in which a piston is reciprocable between a retracted position in which the supply ducts are in communication with the mixing chamber and a forward position in which the supply ducts are shut off from the mixing chamber. The piston is provided with an axial bore through it connected to a supply of air under pressure to enable air to be supplied into the mixing chamber together with the components for producing plastic foam such as foamed polyurethane.

Abstract: A mold including a blind channel connected to the sprue runner so that the first material entering the mold will be trapped in the blind channel.