Sheet and web cleaner

Apparatus for cleaning a travelling sheet or web by sucking debris-laden air from adjacent the surface thereof comprising:

• means defining a substantially rectangular suction slot extending transversely of the path of the sheet or web,
• a hood extending transversely of the path of the sheet or web and having ends adjacent the lateral boundaries of the said path, said hood having a suction outlet at one end thereof and being fluid connected to said suction slot, and
• means for providing substantially uniform airflow into said suction slot comprising:
• (a) means defining an entry slot in said hood for receiving air thereinto, said entry slot tapering in width and having its narrower end adjacent the hood suction outlet, and
• (b) said hood uniformly linearly tapering in cross section and having the largest cross section at the suction outlet.

In apparatus for cleaning a running length of a sheet or web,

• an elongate housing having a wall with a linearly extending opening therein,
• a pair of spaced, parallel channels in said housing having their webs substantially coplanar and facing in the same direction and having their legs extending into said opening,
• linearly extending ion generating means in each said channel having a row of linear emitters parallel to the legs of said channels and having the ionizing points of said emitters remote from said web,
• means for discharging air from said ion generating means, and
• means for securing said channels together as a unit in said spaced, parallel relationship in said housing comprising linear fastener means extending through the legs of said channels, and at least one spacer cooperating with said linear fastener means and located between said channels.

Apparatus for cleaning a running length of a sheet or web of flaccid material by statically neutralizing particles thereon and for maintaining the sheet or web in a substantially planar path comprising:

• (a) first and second ion generating means each including a row of linear emitters having ionizing points transverse of the path of the sheet or web and adjacent thereto,
• (b) a pair of substantially planar and generally imperforate plate means adjacent and parallel to the path of said sheet or web for confining air adjacent to the sheet or web, each said plate means having
• (i) a first portion interrupted substantially only by a row of blower holes, ionizing points of a said generating means extending into said blower holes and providing an air passage about each said ioinizing point,
• (ii) a second, substantially imperforate portion substantially coplanar with said first portion, and
• (c) means defining a suction slot between said rows of emitters extending transverse of said path and spaced along said path from said plate means,
• (d) said apparatus being free of means for physically engaging the sheet or web and further including third and fourth ion generating means and third and fourth plate means in opposed, facing relationship to said first and second ion generating means and to said first and second plate means, respectively, on the opposite side of said path therefrom,
• whereby said plate means confines air adjacent the sheet or web and assists in maintaining the sheet or web out of contact with said apparatus while moving at high speed along said path.