GB2032057A

GB2032057A - Squeeze roller

Info

Publication number: GB2032057A
Application number: GB7930969A
Authority: GB
Original assignee: ROBUR WERKE ZITTAU VEB
Current assignee: ROBUR WERKE ZITTAU VEB
Priority date: 1978-09-07
Filing date: 1979-09-06
Publication date: 1980-04-30
Also published as: DD138794A1; DD138794B1; CH640022A5; DE2931171A1; CS223563B1; GB2032057B

Abstract

A squeeze roller, for use in squeezing machines for the mechanical removal of liquids from broad-fed planar structures such as webs of fabric, paper webs, and the like, comprises a cylindrical carrier roller (1) and a covering (2) of axially disposed and compacted circularly annular active elements fitted to it. The cylindrical carrier roller (1) supports the active covering (2) in suitably alternated arrangement with circular spacer discs (3). The spacer discs (3) have a slightly smaller outside diameter than that of the active covering (2). <IMAGE>

Description

SPECIFICATION Squeeze roller The present invention relates to a squeeze roller for removing liquids from for example broad-fed planar articles such as webs of fabric paper webs, and the like.

Among known methods of removing liquids from broad-fed webs, the mechanical removal using squeeze rollers has been the most economical to date. For example, costs compare 1:40 to 1:160 with those incurred by thermal drying processes.

Prior to drying, therefore, the liquid content is to be largely minimized by mechanical means ideally coming as close to the moisture saturation level of the web as possible. Such a squeezing efficiency greatly depends upon the squeeze roller design.

The hardness of the squeeze roller lining is decisive because the squeezing efficiency is affected by both high and low hardness.

Though high-hardness rollers produce a squeezing gap of desirable narrowness providing very favourable conditions of flow, they are unable, however, to follow web unevenness to a sufficient degree. This disadvantage can be partly offset by increasing the roller pressure, though excessive pressure involves the danger of crushing the fibres with resultant damage to the web.

Rollers of lower hardness are sufficiently expandable to nestle to the web, but the roller pressure allows for a comparatively wide squeezing gap only which, as has been shown by experience, has a negative impact on the squeezing effect due to adverse conditions of flow.

Squeeze roller linings or coverings have been made by axially laminating and compressing thin iaminae of a suitable material such as plastic or fibrous fleece soaked in caoutchouc milk or synthetic resin.

Further, it has been suggested to provide circumferential grooves to rollers to improve both the conditions of flow in the squeezing gap and the ability of the roller to nestle to the web.

To improve the above-described hardness conditions, a known squeeze roller incorporates a covering varied radially with regard to its hardness in a way that a hard roller core is provided with a comparatively thin and elastic jacket.

This roller design has the disadvantage of an unsatisfactory service life, however, because the layer bond is unable to withstand the forces resulting while the covering is being worked.

According to the present invention there is provided a squeeze roller for removing liquid from planar articles, comprising a cylindrical carrier roller, on which are mounted a plurality of circularly annular squeeze elements intercalated axially of the carrier roller with circularly annular spacer members having an external diameter which is less than the external diameter of the squeeze elements.

An embodiment of the present invention will now be more particularly described by way of example snd with reference to the accompanying drawing, the single Figure of which shows a longitudinal section of a squeeze roller.

Referring to the drawing, as a structural member, the squeeze roller comprises a carrier roller 1 having a collar 7 at one side for supporting a circular edge disc 5. The edge disc 5 is followed axially by alternate circular laminae 2 and circular spacer discs 3. The inside diameter of laminae 2 and spacer disc 3 being identical to the outside diameter of the carrier roller 1. Another edge disc 4 is provided at the other end of the pack of laminae 2 and spacer discs 3. A screwed joint, comprising a thread 8 provided to carrier roller 1 and a clamp nut 6, is used to compress and compact the laminae 2 and spacer discs 3 between the collar 7 and the clamp nut 6, the edge discs 4 and 5 mainly serving for uniform transmission of the pressure.

The above described embodiment has a long service life, ensures a low liquid content, a covering of axially laminated laminae and a radially varied hardness avoiding the disadvantage of poor adhesion between layers.

Hence, a roller core of higher hardness and a shell of lower hardness is produced with the shell constituting the active covering, being more resilient than the core, and having the advantage of providing circumferential grooves and eliminating the danger of the shell coming off the core as a result of load.

The change in hardness between shell and core, and hence in the absolute hardnesses of the two portions, can be achieved by the use of appropriate laminae and spacer disc materials and the variation of their thicknesses, on the one hand, and by a variation of the succession of iaminae and spacer discs, on the other.

Thus, a roller embodying the present invention can be ideally and most simply adjusted to the conditions required for any particular type of web.

As a further advantage, the squeeze roller has a radial variation of lining hardness without any danger of the shell coming off the roller core due to being worked during the squeezing process.

Also the roller covering comprises circumferential grooves produced by lamination and providing favourable flow conditions in the squeezing gap.

1. A squeeze roller for removing liquid from planar articles, comprising a cylindrical carrier roller, on which are mounted a plurality of circularly annular squeeze elements intercalated axially of the carrier roller with circularly annular

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Squeeze roller The present invention relates to a squeeze roller for removing liquids from for example broad-fed planar articles such as webs of fabric paper webs, and the like. Among known methods of removing liquids from broad-fed webs, the mechanical removal using squeeze rollers has been the most economical to date. For example, costs compare 1:40 to 1:160 with those incurred by thermal drying processes. Prior to drying, therefore, the liquid content is to be largely minimized by mechanical means ideally coming as close to the moisture saturation level of the web as possible. Such a squeezing efficiency greatly depends upon the squeeze roller design. The hardness of the squeeze roller lining is decisive because the squeezing efficiency is affected by both high and low hardness. Though high-hardness rollers produce a squeezing gap of desirable narrowness providing very favourable conditions of flow, they are unable, however, to follow web unevenness to a sufficient degree. This disadvantage can be partly offset by increasing the roller pressure, though excessive pressure involves the danger of crushing the fibres with resultant damage to the web. Rollers of lower hardness are sufficiently expandable to nestle to the web, but the roller pressure allows for a comparatively wide squeezing gap only which, as has been shown by experience, has a negative impact on the squeezing effect due to adverse conditions of flow. Squeeze roller linings or coverings have been made by axially laminating and compressing thin iaminae of a suitable material such as plastic or fibrous fleece soaked in caoutchouc milk or synthetic resin. Further, it has been suggested to provide circumferential grooves to rollers to improve both the conditions of flow in the squeezing gap and the ability of the roller to nestle to the web. To improve the above-described hardness conditions, a known squeeze roller incorporates a covering varied radially with regard to its hardness in a way that a hard roller core is provided with a comparatively thin and elastic jacket. This roller design has the disadvantage of an unsatisfactory service life, however, because the layer bond is unable to withstand the forces resulting while the covering is being worked. According to the present invention there is provided a squeeze roller for removing liquid from planar articles, comprising a cylindrical carrier roller, on which are mounted a plurality of circularly annular squeeze elements intercalated axially of the carrier roller with circularly annular spacer members having an external diameter which is less than the external diameter of the squeeze elements. An embodiment of the present invention will now be more particularly described by way of example snd with reference to the accompanying drawing, the single Figure of which shows a longitudinal section of a squeeze roller. Referring to the drawing, as a structural member, the squeeze roller comprises a carrier roller 1 having a collar 7 at one side for supporting a circular edge disc 5. The edge disc 5 is followed axially by alternate circular laminae 2 and circular spacer discs 3. The inside diameter of laminae 2 and spacer disc 3 being identical to the outside diameter of the carrier roller 1. Another edge disc 4 is provided at the other end of the pack of laminae 2 and spacer discs 3. A screwed joint, comprising a thread 8 provided to carrier roller 1 and a clamp nut 6, is used to compress and compact the laminae 2 and spacer discs 3 between the collar 7 and the clamp nut 6, the edge discs 4 and 5 mainly serving for uniform transmission of the pressure. The above described embodiment has a long service life, ensures a low liquid content, a covering of axially laminated laminae and a radially varied hardness avoiding the disadvantage of poor adhesion between layers. Hence, a roller core of higher hardness and a shell of lower hardness is produced with the shell constituting the active covering, being more resilient than the core, and having the advantage of providing circumferential grooves and eliminating the danger of the shell coming off the core as a result of load. The change in hardness between shell and core, and hence in the absolute hardnesses of the two portions, can be achieved by the use of appropriate laminae and spacer disc materials and the variation of their thicknesses, on the one hand, and by a variation of the succession of iaminae and spacer discs, on the other. Thus, a roller embodying the present invention can be ideally and most simply adjusted to the conditions required for any particular type of web. As a further advantage, the squeeze roller has a radial variation of lining hardness without any danger of the shell coming off the roller core due to being worked during the squeezing process. Also the roller covering comprises circumferential grooves produced by lamination and providing favourable flow conditions in the squeezing gap. CLAIMS

1. A squeeze roller for removing liquid from planar articles, comprising a cylindrical carrier roller, on which are mounted a plurality of circularly annular squeeze elements intercalated axially of the carrier roller with circularly annular spacer members having an external diameter which is less than the external diameter of the squeeze elements.

2. A squeeze roller substantially as hereinbefore described with reference to the accompanying drawing.