US 5,060,349 A · Compressive treatment of webs

Abstract

A web treating machine and method employing a web-gripping drive surface, a primary member that presses the web against the drive surface, and a stationary retarding surface, supported by a sheet form member, that retards the web before it leaves the drive surface, has the following of features. The sheet form support member is elastically deflectable. A tip deflector applies deflecting pressure on the downstream end of the support member to deflect the support member toward the drive member. A cavity stabilizer, in the form of a second sheet form member, extends in face-to-face reinforcing relationship over the initial portion of the support member in the region immediately downstream of the primary member, the portion of the support member extending between the cavity stabilizer and the tip deflector being relatively unreinforced. The cavity stabilization and tip deflection is obtained by deflection of various spring members, in one instance an advantageous gull-wing form being achieved. Both curved and flat web-driving surfaces are employed. The support member is elastically deflectable about the curved drive surface by applied tip pressure from a relatively straight unstressed shape to a bowed, elastically deformed shape that generally conforms to the curvature of the drive surface. Retarding surfaces shown include sets of ridges and grooves angled to the direction of web drive. Special formations of the retarding surfaces achieve special effects such as a tree bark appearance.

Claims34

Dependent claims

A web treating machine of the type comprising a drive member having a web-gripping drive surface, a smooth-surfaced primary member arranged over the drive member to press the web into driven engagement with the surface of the drive member, and a generally stationary retarding surface arranged after the primary surface to engage and retard the web before the web has left the drive member, the retarding surface being supported by a sheet form support member, having the following combination of features:

a) said sheet form support member is a longitudinally inextensible, elastically deflectable spring member,
b) a tip deflector is constructed and arranged to apply deflecting pressure on the downstream end portion of said longitudinally inextensible support member to deflect said support member toward said drive member,
c) there being a cavity stabilizer in the form of a portion of a second sheet form member which extends in face-to-face reinforcing relationship over the initial portion of said support member in the region immediately downstream of said primary member, thereby providing in said region a dimensional stabilizing effect in the normal direction to the cavity defined between said longitudinally inextensible sheet-form support member and said web-gripping drive surface,
d) the portion of said longitudinally inextensible support member extending between said cavity stabilizer and said tip deflector being relatively reinforced.

1 more element

A web treating machine of the type comprising a drive member having a curved web-gripping drive surface, a smooth-surfaced primary member arranged over the drive member to press the web into driven engagement with the surface of the drive member, and a generally stationary retarding surface arranged after the primary surface to engaged and retard the web before the web has left the drive member, the retarding surface being supported by a sheet form support member, having the following combination of features:

a) said sheet form support member is a longitudinally inextensible spring member elastically deflectable about the curved drive surface by applied tip pressure from a relatively straight unstressed shape to a bowed, elastically deformed shape that generally conforms to the curvature of the drive surface,
b) a tip deflector is constructed and arranged to apply deflecting pressure on the downstream end portion of said longitudinally inextensible support member to deflect said support member into conforming relationship with said drive member,
c) there being a cavity stabilizer in the form of a portion of a second sheet form member which extends in face-to-face reinforcing relationship over the initial portion of said support member in the region immediately downstream of said primary member, thereby providing in said region a dimensional stabilizing effect in the normal direction to the cavity defined between said longitudinally inextensible sheet-form support member and said web-gripping device surface,
d) the portion of said inextensible support member extending between said cavity stabilizer and said tip deflector being relatively unreinforced.

1 more element

a) said sheet form support member is elastically deflectable,
b) a tip deflector is constructed and arranged to apply deflecting pressure on the downstream end portion of said support member to deflect said support member toward said drive member,
c) there being a cavity stabilizer in the form of a portion of a second sheet form member which extends in face-to-face reinforcing relationship over the initial portion of said support member in the region immediately downstream of said primary member, thereby providing in said region a dimensional stabilizing effect to the cavity defined between said sheet form support member and said web-gripping drive surface,
d) the portion of said support member extending between said cavity stabilizer and said tip deflector being relatively unreinforced,
e) said tip deflector and said cavity stabilizer comprising spaced apart portions of a supplemental sheet spring member, the portion of said supplemental sheet spring member that defines said tip deflector being in face-to-face engagement with the upper surface of the end portion of said support member, said supplemental sheet spring member having, in unstressed condition, a precurved, outwardly convex portion spanning between said portions that define said cavity stabilizer and said tip deflector.

2 more elements

In a web treating machine of the type comprising a drive member having a web-gripping drive surface, a smooth surfaced sheet-form primary member arranged over the drive member to press the web into driven engagement with the drive surface, a presser member defining a presser edge for pressing said primary member against the drive member and a generally stationary retarding surface arranged after the primary surface to engage and retard the web before the web has left the drive member, the retarding surface being supported by a sheet spring member which has a rearward portion extending rearwardly over the primary member and under said presser member, the improvement wherein said sheet spring member has, in unstressed condition, a precurved, outwardly convex portion spanning between a point upstream of said presser member edge to a region substantially downstream of said edge,

said sheet spring member being constructed and arranged so that, in operating position, said presser member locally elastically deflects said sheet spring member into a slightly reversely curved, outwardly concave form whereby in the region of said presser member and immediately upstream and downstream thereof said spring member has a stable prestressed generally gull-wing shape.

Dependencies are inferred from the claim text.

Compressive treatment of webs

Life of this patent

Compressive treatment of webs

Life of this patent

Abstract

Claims34