Oy Tampella Ab

Eero Hanhilahti

Pekka O Haikkala

Matti I Aario

Raimo Pessa

A sealing arrangement for a shutter for a feeding chamber of a continuously operating pressure grinder. The feeding chamber is provided with an inlet opening for feeding wood batches at atmospheric pressure into said feeding chamber and with an outlet opening for feeding said wood batches into the grinding chamber at overpressure. Each opening of said feeding chamber is provided with a shutter movable between an opened position and a closed position for preventing of escape of said overpressure through said feeding chamber. The feeding chamber is provided with a fixed guide supporting the shutter during its movement between opened and closed positions. Said guide comprises two parallel support surfaces between which the shutter is slidably mounted. The distance between said support surfaces is greater than the thickness of the shutter adjacent said support surfaces so that the shutter is displaceable towards and away from said support surfaces in a direction perpendicular to said support surfaces. A sealing element is provided in one of said support surfaces in such a way that, when the shutter is displaced away from said one support surface towards the other support surface, the shutter is released from contact with said sealing element. In this way the shutter is due to the pressure difference between opposite sides of the shutter pressed against said one support surface and against said sealing element but is released from contact with said support surface and said sealing element when the pressures are equilized on opposite sides of the shutter and can be moved to open and closed positions without said contact.

Growing community of inventors

Varalank, Finland

Eero Hanhilahti