Patent EA-000596-B1 (EA)
Title: Under felt inclined flat former to produce multilayer or monolayer sheet of paper
Inventor: CABRERA Y LOPEZ CARAM LUIS FER
IPC: D21F1/02
Filed: 1997-09-05
Abstract: 1. An under felt inclined former in a papermaking machine, said former comprising: a breast roll (97'); a support roll (32') downstream of the breast roll (97'); a forming fabric (72'); a drainage means (167, 168) positioned between the breast roll (97') and support roll (32') for drainage of liquid from the forming fabric (72'); said breast roll (97'), support roll (32'), forming fabric (72') and drainage means (167, 168) being positioned under a papermaking felt on a papermaking machine; said forming fabric (72') engaging said breast roll (37'') and support roll (32') in an endless loop and passing over said drainage means (167, 168) which removes liquid from stock on the forming fabric and activity means which creates activity in the stock; said drainage means includes activity means which forces a portion of liquid drained back through the fabric to cause activity in the stock therein whilst allowing draining liquid therefrom; a couch roll (25') positioned above a papermakers felt (73') and above said support roll (32') to cause said papermaking felt to engage the forming fabric so as to allow a transfer of a sheet formed on the forming fabric (72') to said papermaking felt (73'); said drainage means and forming fabric being inclined with respect to a papermakering felt; a head box (164) positioned at the beginning of the forming fabric for placing stock thereon; and wherein stock is introduced onto the forming fabric by the head box (164) which, due to a rotation of the breast roll (97') and support roll (32'), causes the forming fabric to pass over the drainage means (167, 168) causes stock activity and liquid to be drained from the stock forming a sheet which is then transferred to the papermaking felt (73') at a junction formed between the couch roll (25') and support roll (32'). 2. The under felt inclined flat former in accordance with Claim 1 wherein the activity means comprises at least one activity forming blade (167, 168). 3. The under felt inclined flat former in accordance with Claim 2 further comprising activity inducing means (189) located at the head box (164) for inducing activity and dispersion of stock prior to flowing on to the forming fabric. 4. The under felt inclined flat former in accordance with Claim 2 wherein said support roll is a cylinder mold. 5. The under felt inclined flat former in accordance with Claim 2 wherein said head box (164) comprises a stepped diffuser (188) which maintains the stock in a state of dispersion. 6. The under felt inclined flat former in accordance with Claim 3 wherein the activity inducing means comprises an upper activity lip (189) located at the head box for creating activity in the stock as it is fed on to the forming fabric. 7. The under felt inclined flat former in accordance with Claim 2 wherein said former includes support means (152, 153) for supporting said former under a papermaking felt and includes means for pulling the support roll away from under a papermaking felt without stopping production thereon. 8. The under felt inclined flat former in accordance with Claim 2 which includes a plurality of under felt inclined formers which are positioned in series and used in the formation of a sheet. 9. The under felt inclined flat former in accordance with Claim 9 wherein the angle of inclination of the former is approximately 5 to 10 degrees with respect to the papermaker's fabric (73'). 10. The under felt inclined flat former in accordance with Claim 6 wherein said activity lip causes a variation of the velocity of the flow as the stock flows in a machine direction.