초록 ▼

A pressure-activated valve for conducting pressurized gas into a mold cavity of an injection molding apparatus is preferably constructed as an easily replaceable unit. The preferred valve includes a pin having a flared head section. The head section has a planar face transverse to an axis of the pin

A pressure-activated valve for conducting pressurized gas into a mold cavity of an injection molding apparatus is preferably constructed as an easily replaceable unit. The preferred valve includes a pin having a flared head section. The head section has a planar face transverse to an axis of the pin so as to approximately conform to a neighboring contour of the mold cavity. The valve also includes a body in which a passageway intersects a second end of the body to define a port and a flaring seat communicates through a first end of the body between the passageway and the mold cavity. A restrainer which abuts against the second end of the body includes a guideway aligned with the passageway through the body as well as at least one cross-channel which admits pressurized gas to that passageway through the port. The pin extends through both the passageway and the guideway so that its head portion is positioned near the seat. A spring retainer threadedly engages an end portion of the pin which projects out of the guideway in the restrainer. A coiled compression spring encircling the restrainer is compressed between the spring retainer and the second end of the body so that the spring force urges the head section of the pin against the seat to close the valve. The valve allows the pressurized gas to flow into the mold cavity while preventing the molding composition from flowing back and obstructing a supply of pressurized gas to the valve.

대표청구항 ▼

[ What is claimed is:] [1.] A pressure-activated valve for an injection molding apparatus a comprising:a pin having a cylindrical or prismatic stem section and a flared head section;a valve body having a first end and a second end, said valve body including a passageway communicating with said first

[ What is claimed is:] [1.] A pressure-activated valve for an injection molding apparatus a comprising:a pin having a cylindrical or prismatic stem section and a flared head section;a valve body having a first end and a second end, said valve body including a passageway communicating with said first and second ends;a port proximate said second end and communicating with said passageway for receiving pressurized fluid;said valve body including a flared seat proximate said first end and communicating with said passageway, said stem section of said pin being positioned in said passageway with said head section positioned near said seat so as to provide a radial clearance of approximately 0.002 inch to 0.006 inch (approximately 0.05 mm to 0.15 mm) between said stem section and said passageway through said valve body; anda compression spring operatively associated with said stem section to bias said head section into seated engagement with said seat.