DE202020102760U1 - Rotary press for processing hides - Google Patents

Abstract

Rotary press for processing hides, which includes:
- Two superimposed cylinders (2, 3) with opposing parallel axes (X, X '), an upper (3) and a lower (2) and at least one of them with motor drive, a gap (4) between them for crossing the skins limit;
- A feed belt made of felt (5) which is closed in a ring around the lower cylinder (3); characterized in that it comprises a damping layer (6) surrounding the side surface of at least one of the above-mentioned upper and lower cylinders (2, 3).

Description

Field of application

This invention relates to a rotary press for processing hides according to the preamble of the independent main claim.

Rotary presses are often used in the tanning industry for the finishing of skins and in particular for drying, stretching and / or printing skins and the like.

In addition to being used in the tannery industry, the press which is involved can advantageously also be used to process materials other than sheets, such as synthetic leather, fabric or synthetic materials.

State of the art

Traditionally, in the tannery sector, the presses for processing hides are essentially comparable to calenders, which comprise two cylinders with opposing parallel axes, which delimit a gap between them which is crossed by the hides to be processed.

The upper cylinder is preferably heated and, depending on the processing to which the skin is to be subjected, is equipped with a smooth (chromed) or engraved (e.g. with corrugations) side surface.

The press also has a feed belt that is wound in a ring on the lower cylinder and on a tensioning cylinder in front of the pair of cylinders that compress the skin.

This band also has the function of gradually and evenly transferring the pressure exerted on the skin by the two cylinders, thereby avoiding excessive stress on the skin.

This ring-wound tape is advantageously made of felt.

This material, which essentially consists of a cloth made of compressed wool fleece material impregnated with adhesive, has shown excellent mechanical properties in practice and has proven in particular to be adequately soft and porous to dampen the effect of the cylinders on the skin.

Nevertheless, the rotary presses using this felt band wound in a ring on the lower cylinder have not proven to be free of problems.

The main problem lies in the fact that the cyclical pressure action and the felt tape exposed to the temperature transferred from the upper cylinder quickly loses its mechanical properties and is compressed to a lower strength, so its elastic response and thus ultimately the dampening effect on the skin is reduced.

To his surprise, the proprietor of this application found that this gradual loss of the mechanical properties of the felt is at least in part due to the pressure impulses that are transmitted from the folds of the skin and cause concentrated stresses that locally damage the felt tape.

The impairment of the felt tape leads to a less than optimal finishing of the skin, which turns out to be less soft and rough. In addition to changing the thickness of the band wound in a ring, its length also changes with its gradual wear, which leads to the need for numerous adjustments of the tensioning cylinder on which the felt band is wound in a ring.

Replacing a felt belt with a new one naturally results in reduced productivity due to the downtimes required to stop the machine and also entails increased costs both for the personnel employed and for the belt that is frequently replaced.

Presentation of the invention

In this situation, the problem underlying this invention is to eliminate the shortcomings of the above-mentioned known technology and to provide a rotary press for the processing of skins which requires less maintenance.

Another object of this invention is to provide a rotary press for processing hides, which has a felt belt which, in comparison to the presses of the type known today, requires replacement by a new one for a higher number of working hours.

Another object of this invention is to provide a rotary press for processing hides which enables the surface finish of the hides to be achieved in an optimal manner and for a longer period of time.

These and still other objects are all achieved by the rotary press for processing hides which is the subject of this invention, the two superimposed cylinders with opposite parallel axes, an upper and one lower and at least one with motor drive, which define a gap between them for crossing the skins, and a ring around the lower cylinder ( 3rd ) includes closed felt feed belt.

According to the idea on which this invention is based, the press also comprises a damping layer which surrounds the side surface of at least one of the above-mentioned upper and lower cylinders.

Figure list

• - 1 eine allgemeine schematische Ansicht der Rundlaufpresse für die Verarbeitung von Häuten nach dieser Erfindung zeigt;
• - 2 ein Einzelteil der Rundlaufpresse aus 1 in perspektivischer Ansicht in Bezug auf einen mit einer Polyurethanschicht verkleideten unteren Zylinder zeigt.

The technical characteristics of the invention are clearly apparent from the content of the claims listed below, and the advantages thereof will become more apparent from the detailed description below, given with reference to the drawings in the appendix, which some and not, according to the aims set out above represent limiting examples of the same, in which:

• - 1 Figure 3 shows a general schematic view of the rotary press for processing hides according to this invention;
• - 2nd a single part of the rotary press 1 in perspective view with respect to a lower cylinder clad with a polyurethane layer.

Detailed description of an example of the preferred design

With reference to the drawings in the plant, the rotary press for processing hides, which is the subject of this invention, was used in its entirety with 1 designated.

The rotary press 1 according to this invention is intended to be used in the tanning industry for the finishing of skins and in particular for drying, stretching and / or printing skins and the like.

The press 1 , which is involved, can advantageously also be used, in addition to in the tannery industry, for processing materials other than sheets, such as synthetic leather, fabric or synthetic materials.

According to the preferred embodiment of the invention shown in the systems, the rotary press comprises 1 one generally with 10th designated support structure supported on the floor and two cylinders lying one above the other 2nd and 3rd with opposing parallel axes X, X ', namely an upper one 2nd and a lower one 3rd .

The two cylinders 2nd , 3rd define a horizontally arranged gap between them 4th to pass through the skins.

The press 1 also includes a felt feed belt 5 , which is ring-shaped around the lower cylinder 3rd closed is.

At least one of the two cylinders 2nd , 3rd is motorized to drive the skins across the gap 4th to transport.

At least the lower cylinder is advantageous 3rd equipped with motor drive and preferably the feed belt 5 by at least one more, in relation to the above-mentioned cylinders lying one above the other 2nd , 3rd laterally offset cylinder 7 wrapped around a flat and horizontal conveying area 8th to define the skins on which the skins can be spread, then from the tape 5 to the gap 4th to be promoted.

Preferably the top cylinder 2nd with suitable heating elements 9 heated and is equipped with a smooth (chrome-plated) or engraved (e.g. with corrugations) side surface depending on the processing to which the skin is to be subjected.

The ring-shaped closed felt band 5 corresponds to the type normally used in tannery on continuous printing and stretching machines and can consist, for example, of a 100% wool or a mixed felt with, for example, 30% wool - 70% synthetic material.

In any case, the term "felt" is any ribbon 5 of the type commonly used in the tannery sector on presses for processing hides.

According to the idea underlying this invention, the press comprises 1 also an advantageously made of polyurethane material, advantageously high density and in particular very resistant to abrasion and antistatic, existing damping layer 6 which is the side surface of at least one of the above 2nd and lower cylinder 3rd surrounds and advantageously the side surface of the lower cylinder 3rd .

This layer 6 adheres advantageously to the side surface of the lower cylinder 3rd , since it is attached to this, for example, and preferably by vulcanization or in another way using mechanical means or a layer of adhesive.
The damping layer 6 is therefore between the lower cylinder and the felt feed belt 5 used.

This layer advantageously has a thickness between 15 and 30 mm and preferably a hardness between 65 and 95 shore.

With these values, an optimal damping was found, which extends the life of the felt belt.

The damping layer made of polyurethane 6 insulates the stresses that the felt tape 5 is exposed when it comes into cyclical contact with the skin, especially with wrinkles and folds of the skin that are suitable on the tape 5 to exert localized compressions on the felt tape 5 without the cushioning layer 6 made of polyurethane would wear out quickly.

Claims (8)

Rotary press for processing hides, comprising: - two superimposed cylinders (2, 3) with opposing parallel axes (X, X '), an upper (3) and a lower (2) and at least one of them with motor drive, the define a gap (4) between them for crossing the skins; - A feed belt made of felt (5) which is closed in a ring around the lower cylinder (3); characterized in that it comprises a damping layer (6) surrounding the side surface of at least one of the above-mentioned upper and lower cylinders (2, 3). Rotary press for the processing of hides Claim 1 , characterized in that said damping layer (6) surrounds the side surface of said lower cylinder (3) since it is inserted between the latter and said felt feeding belt (5). Rotary press for the processing of hides Claim 1 or 2nd , characterized in that said damping layer (6) consists of high-density polyurethane. Rotary press for the processing of hides Claim 3 , characterized in that said damping layer (6) made of polyurethane has a hardness between 65 and 95 Shore. Rotary press for the processing of hides Claim 3 or 4th , characterized in that said damping layer (6) made of polyurethane has a thickness between 15 and 30 mm. Rotary press for processing hides according to any one of the preceding claims, characterized in that said damping layer (6) is attached to the side surface of said lower cylinder (3) by means of vulcanization. Rotary press for the processing of hides Claim 2 , characterized in that said belt (5) is wound around at least one further cylinder (7) which is laterally offset in relation to the above-mentioned two superimposed cylinders (2, 3), around an area for depositing and transporting (8) said Define skins to the mentioned gap (4). Rotary press for the processing of hides Claim 1 , characterized in that heating elements (9) connected to said upper cylinder (2) are provided.

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