Seal for clean-in-place enclosure for a packaging machine

Sealing apparatus for producing a selectively actuatable fluid-tight seal between a stationary housing and the outer circumference of a reciprocative member passing through said housing comprising

• a stationary seal plate adapter having first and second opposite surfaces and a throughbore defined between said opposite surfaces, said throughbore including a portion of the inner circumferential wall thereof tapered radially outwardly and downwardly in a direction away from said first surface thereof and terminating short of said second surface thereof to further define a non-tapered continuation portion of the inner circumferential wall of said seal plate adapter adjacent its second surface,
• a seal actuator/bearing component having first and second opposite ends and an opening having first and second ends defined between said opposite ends of said seal actuator/bearing component, said first end of said opening including a circumferential wall portion thereof tapered radially outwardly and upwardly toward said first end of said seal actuator/bearing component, said second surface of said seal plate adapter and said first end of said seal actuator/bearing component being adjacent one another and with their respective throughbore and opening being in register, at least said first end of said actuator/bearing component being slidably disposed within said non-tapered portion of said throughbore through said seal plate adapter, to thereby collectively define an annular space within said throughbore through said seal plate adapter,
• a resilient member disposed within said annular space and encircling the outer circumference of a reciprocative member which reciprocates through said annular space,
• said seal actuator/bearing component being movable toward and away from said seal plate adapter in a manner and to an extent whereby said resilient member either resides within said annular space in a relaxed state and out of material engagement with the reciprocative member which reciprocates through said annular space, or said resilient member is compressed generally radially thereof between said tapered surfaces of said seal plate adapter and said seal actuator/bearing component to thereby urge said resilient member into sealing engagement with said reciprocative member which reciprocates through said annular space.

A method for selectively sealing a reciprocative member with respect to a sealing apparatus disposed thereabout comprising the steps of

• disposing a seal plate having first and second opposite surfaces in fixed position relative to the reciprocative member,
• defining a throughbore between said opposite surfaces of said seal plate,
• providing said throughbore with a first inner wall portion which tapers radially outwardly from said first surface and downwardly toward said second surface, said first tapered wall portion terminating short of said second surface to define a non-tapered inner wall portion of said throughbore adjacent said second surface of said seal plate,
• encircling the reciprocative member with an annular actuator/seal component having first and second ends, said first end being at least partially received within said non-tapered wall portion of said throughbore, and encircling the reciprocative member,
• tapering said first end of said actuator/seal component radially outwardly and upwardly of said annular actuator/seal component whereby said tapered surface of said seal plate and said tapered end of said actuator/seal component face one another and define therebetween an annular space having oppositely tapered facing surfaces,
• disposing a resilient member within said annular space and in encircling relationship to the reciprocative member,
• providing a reciprocative piston member in operative relationship to said actuator/seal member for the application of pressure against said actuator/seal member to thereby move said actuator/seal member toward said seal plate,
• applying a force to said actuator/seal member sufficient to move said actuator/seal member toward said stationary seal plate and compress said resilient member between said facing tapered surfaces of said annular space and into sealing engagement with the reciprocative member.