公开(公告)号：BR7019357D0

公开(公告)日：1973-01-11

申请号：BR21935770

申请日：1970-05-29

Applicant: IBM

Inventor： MCCORNACK R ,  O BRIAN P ,  GREER D ,  SIMPSON H

IPC: B41J13/00 ,  B41J29/08 ,  G10K11/16 ,  B41J29/10

Abstract: 1282693 Typewriters INTERNATIONAL BUSINESS MACHINES CORP 8 May 1970 [2 June 1969] 22257/70 Heading B6F A sound-deadening device for typewriters comprises a cavity member 50 which together with an enclosure 19 and a backing member 29 defines ingress and egress slots 33, 35 for paper passing around a platen 13, the cavity member 50 being sound absorbing. As shown, the cavity 50 comprises a housing enclosing members 117, 118, 119, 120 of polyurethane foam, the outer members 117, 120 comprising acoustic slot filters. Alternatively, the cavity 50 may be open and lined with sound absorbent material.

公开(公告)号：SE358116B

公开(公告)日：1973-07-23

申请号：SE759070

申请日：1970-06-02

Applicant: IBM

Inventor： BUEHNER W ,  GREER D ,  MCCORNACK R ,  O BRIAN P ,  SIMPSON H

IPC: B41J13/00 ,  B41J29/08 ,  G10K11/16 ,  B41J29/10

Abstract: 1282693 Typewriters INTERNATIONAL BUSINESS MACHINES CORP 8 May 1970 [2 June 1969] 22257/70 Heading B6F A sound-deadening device for typewriters comprises a cavity member 50 which together with an enclosure 19 and a backing member 29 defines ingress and egress slots 33, 35 for paper passing around a platen 13, the cavity member 50 being sound absorbing. As shown, the cavity 50 comprises a housing enclosing members 117, 118, 119, 120 of polyurethane foam, the outer members 117, 120 comprising acoustic slot filters. Alternatively, the cavity 50 may be open and lined with sound absorbent material.