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US 3,937,919 AGranted
Fixing device
AssigneeOce-van der Grinten N.V.
InventorsHenricus P. M. Clerx, Pieter M. J. Extra, Leonardus L. M. Keursten, Franciscus M. J. Peeters
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AssigneeOce-van der Grinten N.V.
InventorsHenricus P. M. Clerx, Pieter M. J. Extra, Leonardus L. M. Keursten, Franciscus M. J. Peeters
Estimating the term…
For fixing electrostatically formed images of thermoplastic powder on copy sheets, an elastic roller and a heated rigid roller form a nip through which each sheet is passed with its image side engaged by the elastic roller, and the elastic roller has a pliable annular body formed with circumferential surface grooves or ribs which cooperate with organs of complementary form for separating each sheet from the roller surface behind the nip, yet which provide an even roller surface in the nip by being elastically deformed therein. The rigid roller is formed with circumferential surface grooves which also cooperate with complementary sheet separating organs. The separating organs cooperating with grooves may be blades extending into them behind the nip, or wires extending in them through the nip; those cooperating with ribs may be blades having profiled edges held almost in contact with ribbed regions of the elastic roller surface.
Device for fixing a thermoplastic powder image on a support, comprising an elastic roller that is to contact the image side of the support and a substantially rigid roller having a surface sufficiently rigid to hold its shape under pressure against said elastic roller, said rollers together forming a nip through which the support is transported, the elastic roller comprising an elastically pliable annular body the outer surface of which is provided with at least one circumferential formation lying radially away from the contour thereof, and a separating organ complementary to and coacting with each said formation to assure separation of the support from said surface, each said formation being of such dimensions and said surface being sufficiently pliable that each said formation is deformed elastically by pressure of said rigid roller so as to form an even elastic roller surface in said nip.
Device for fixing a thermoplastic powder image on a support, comprising an elastic roller that is to contact the image side of the support and a substantially rigid roller having a surface sufficiently rigid to hold its shape under pressure against said elastic roller, said rollers together forming a nip through which the support is transported, the elastic roller having an elastically pliable annular body the outer surface of which is provided with at least one elastically pliable riblike thickening of sufficiently small protending volume that each said thickening is depressed in the nip between the rollers so as to create an even elastic surface therein.
Device for fixing a thermoplastic powder image on a support, comprising an elastic roller that is to contact the image side of the support and a substantially rigid roller having a surface sufficiently rigid to hold its shape under pressure against said elastic roller, said rollers together forming a nip through which the support is transported, the elastic roller having an elastically pliable annular body the outer surface of which has at least one circumferential groove formed therein, and a separating organ extending into each said groove, each said groove being of such dimensions and said surface being sufficiently pliable that the groove is pressed closed to form an even elastic roller surface in said nip.
Device for fixing a thermoplastic powder image on a support, comprising an elastic roller that is to contact the image side of the support and a substantially rigid roller having a surface sufficiently rigid to hold its shape under pressure against said elastic roller, said rollers together forming a nip through which the support is transported, the elastic roller having an elastically pliable annular body forming a pliable outer surface and the rigid roller having a non-pliable sheath, said sheath having at least one circumferential groove formed therein, and a separating organ extending into each said groove to assure separation of said support from the rigid roller behind said nip.
Dependencies are inferred from the claim text.