US3889495A

US3889495A - Roller-lock

Info

Publication number: US3889495A
Application number: US403647A
Authority: US
Inventors: Der Eltz Hans-Ulrich Von; Franz Lappe; Albert Reuther
Original assignee: Hoechst AG
Priority date: 1972-10-07
Filing date: 1973-10-04
Publication date: 1975-06-17
Anticipated expiration: 1992-06-17
Also published as: CA1018201A; JPS4971282A; DE2249333C3; DE2249333B2; CH563488A5; DE2249333A1; GB1441934A; BE805773A; IT995654B; FR2202181B1; FR2202181A1

Abstract

A roller-lock is used as a sealing system for the inlet and outlet of material webs into or out of autoclaves and consists of a series of individual pressure chambers which are separated or defined by pairs of rollers whereby, the material passing from the atmosphere into the the pressure chamber of the autoclave moves through several staged pressure chambers having increasing pressure therein. When the material passes out of the autoclave it moves through the same chambers in an opposite direction to be subjected to staged decreasing pressure as it passes out of the sealing system.

Description

United States Patent [191 von der Eltz et al.

[ June 17, 1975 1 ROLLER-LOCK [73] Assignee: Hoechst Aktiengesellschaft,

Frankfurt am Main, Germany [22] Filed: Oct. 4, 1973 [21] Appl. No.: 403,647

[30] Foreign Application Priority Data Oct. 7, 1972 Germany 2249333 [52] US. Cl. 68/5 E; 34/242 [51] Int. Cl. D06! 1/10 [58] Field of Search 68/5 E; 34/242 [56] References Cited UNITED STATES PATENTS 1,633,121 6/1927 Minton 68/5 E 2,834,193 5/1958 Fahringer 68/5 E 2,873,597 2/1959 Fahringer 68/5 E 3,066,518 12/1962 Fujihashi... 3,158,507 11/1964 Alexander. 3,460,359 8/1969 Schiffcr 34/242 X Primary Examiner--l-larvey C. l-lornsby Assistant ExaminerPhilip R. Coe Attorney, Agent, or Firm-Curtis, Morris & Safford [57] ABSTRACT A roller-lock is used as a sealing system for the inlet and outlet of material webs into or out of autoclaves and consists of a series of individual pressure chambers which are separated or defined by pairs of rollers whereby, the material passing from the atmosphere into the the pressure chamber of the autoclave moves through several staged pressure chambers having increasing pressure therein. When the material passes out of the autoclave it moves through the same chambers in an opposite direction to be subjected to staged decreasing pressure as it passes out of the sealing systern.

6 Claims, 1 Drawing Figure ROLLER-LOCK It is known that textile materials of synthetic fibres can be dyed and fixed, continuously, by pressure steaming prepadded dyestuffs onto the fibre. In the case of the continuous pressure steamers used up to now for this purpose the textile material padded with the dyestuff padding liquor passes through a roller-lock into the autoclave, which is under high-pressurized saturated steam, and is then run through the autoclave via a system of guide rollers and finally leaves the autoclave via a second roller-lock.

ln general, pressures of 2 to 3 bars (i.e., approximately 1 to 2 atmospheres gauge) are used for the fixation of the dyestuffs. The steaming period and therefore the speed of goods depends on the dyestuffs used, the nature of the fibre material and the pressure available. When higher pressure are applied, the periods required for the fixation are correspondingly shorter, thus enabling a higher production speed. However, any further increase of the pressure to more than 3 barsis limited by the fact that the roller-locks available up to now allow only a pressure of up to 3 bars (i.e., to approximately 2 atmospheres gauge), and generally only up to 2, 5 bars. The construction of the hitherto onestep roller-locks and of a number of similarly acting sealing systems, such as water cascades, is adequately described in the literature.

In bleachings continuous pressure steamers with so called *membrane" or lip sealings are used, wherein elastic leaves are pressed onto the material by the inner pressure of the steamer and thereby make possible a sealing of more than 3 bars. For dyeing or printing purposes these lip sealings are, however. unsuitable because the lips leave behind sliding tracks on the padded, wet textile material.

As far as the known constructions of pressure chamber locks are concerned, wherein elastic sealing elements with pneumatic or hydraulic pressure control are used in the framework of one-step roller-locks, for the complete sealing of the treatment vessel under excess pressure against the atmospheric pressure such high pressures applied to the roller are necessary for the seal elements that the service life of the elastic materials used is unacceptably low because of deterioration due to friction whether through abrasion or frictional heat. The seal of usual working pressures of 2.5 to 3 bars demands, furthermore, such high pressing powers applied to the rollers that padding liquor is pressed out of the wet material, which liquor gathers in the squeezing slit or runs off from there, again causing uneven dyeings.

It has now been found that continuous pressure steamers for the high-pressure/saturated steam treatment of web-shaped textiles, preferably of synthetic fibre materials, can also be used for pressures of more than 3 bars (approximately 2 atmospheres gauge), if a roller-lock is used as the sealing system for the material inlet and outlet into or out of autoclaves. In accordance with the present invention this roller lock consists of a series of individual pressure chambers, whereby in the case of the material inlet from the outer atmospheric pressure to the working pressure in the autoclave pressure stages with increasing pressure are arranged while in the case of the material outlet in the opposite transport direction pressure stages with falling pressure are arranged behind one another. This roller-lock characterized by the fact that the pressure chambers consist of pairs of rollers of various hardness and in each case are spaced to define squeezing slit along the roller width in pairs on the cylindrical jacket thereof, whereby, when the direction of rotation remains the same, the roller pairs concerned are means for the material inlet as well as also for the material outlet. The transport of the material web is directed between hard rollers and rollers coated with an elastic covering.

Within the framework of the present invention attempts have been successful in overcoming the difference between atmospheric pressure and working pressure without disturbing the safety of the process when using the roller-lock of the invention. Therefore, higher production speeds are advantageously obtained by the higher saturation steam pressure.

Contrary to the state of the art the following differences or advantages result from the use of the new sealing system:

1. The roller-lock according to the invention serves at the same time for the roller inlet and outlet. That means a considerable simplification of the pressure steamer, increase of operating safety and reduction of the susceptibility to interruption.

2. Since the transition from outer atmospheric pressure to the increased working pressure takes place by pressure stages with relatively small pressure differences, the pneumatic or hydraulic pressures of the sealing elements are likewise small, which is of decisive importance as far as the friction on the seal points are concerned. The rubbings and the occurance of frictional heat, which, therefore, contribute to the wear of the seals, are reduced strongly according to the invention, which in turn increases the life service of the elastic sealing elements on jacket and front ends of the rollers. By corresponding coatings which reduce the friction, such as by plastics materials with smooth surface for example polytetrafluoroethylene, a further reduction of the friction is obtained.

3. The building up of higher working pressures (approximately to 6 or 7 bars) in the autoclave is made possible by the pressure stages with safe sealing for the first time. With one-step sealing working pressures to 3 bars can only be obtained by using strongest pressing powers applied to the elastic elements with all their disadvantages as regards wear of the sealings.

4. Through the higher working pressure reduction of the dwelling times in the pressure steamer and, therefore, an increase of the production speed are obtained.

5. The sealing is carried out not in the fiber material, as with lips, pressure tube or membrane seals of the prior art but only on the rollers, whereby an impairment of the material surface is eliminated and the regularity of the absorption of the dye liquor is as sured (i.e. no slide tracks are formed).

6. Through the combination of elastic and hard rollers the sealing on the squeezing slit is obtained without excessively high pressures. The dye liquor absorbed is not pressed out.

Referring to the single FIGURE of the drawing when working with the roller-lock of the invention the material web 1 is passed through, after padding with a dye stuff liquor, between the first pair of rollers. The pair of rollers consists of an elastically mounted smooth metal roller 3 and of a soft roller 4 provided with an elastic covering 9, for example of rubber or soft plastic. The metal rollers (hard rollers) are embedded for the sealing against the atmospheric pressure in plastic cups or pressure tubes 5, the pressing power of which may be regulated against the rollers by applying pneumatic or hydraulic pressure via corresponding feed pipes 7. The material comes into the first pressure stage chamber 6, which is isolated from the outer atmospheric pressure through the squeezing between the pair of roller pairs 3, 4 on the cylinder circumference on the one side. The front ends, axles and bearings are sealed by known elastic sealing elements with adjustable pneumatic or hydraulic pressure. The pressure (against the atmospheric pressure) in the first pressure stage chamber 6 is only higher by a part amount of the working pressure provided for, for example, on average by 0.5 to 1 bars. This small pressure difference makes it possible to keep low also the pressures applied of the elastic pressure tubes and the roller pair 3/4. The pressure tubes or plastic cups 5 themselves are provided with a sliding covering 8 adjacent the roller 3 so that the friction resistance, the seal and the frictional heat are then likewise low, and the dye liquor is not pressed out at the squeezing slit. Pressure stage chambers 6 opposite one another should be expediently under the same pressure.

Through further pressure stage chambers 6 corresponding to one another when the further transport is carried out the total pressure difference is built up gradually from atmospheric outer pressure to the working pressure to be reached which may be higher than 3 bars. These pressure chambers 6 are connected with the pressure steam conduit via reducing valves of corresponding setting. The material runs through the auto clave 2 (owing to the higher pressure with increased speed), is there exposed to the effect of the high pressurized saturation steam and brought back to the rollerlock. The last two pressure stage chambers 6 adjacent the autoclave 2 can be provided with a compressed air device to form a static pneumatic counter pressure pad in order to counteract the expansion of the saturated steam and the condensation. Rollers and elastic sealing elements should be provided expediently with a friction reducing plastics covering (for example polytetrafluoroethylene) as is the case generally with selflubricating bearings.

The same roller-lock is used for the material inlet as also for the material outlet without it being necessary to undertake alterations. The material runs through the pressure stage chambers at the outlet and the roller pairs in the opposite direction as with the material widths running in whereby the pressure is now released by stages.

An example for operation for a roller-lock according to the invention is given in the drawing below as a scheme of the side view. The reference figures used here have the following significance:

. material web autoclave smooth metal roller soft roller pressure cups or tubes pressure stage chambers (possible with static counter pressure by compressed air) 7. conduits for applying pneumatic or hydraulic pressure 8. sliding covering 9. elastic roller covering What is claimed is:

1. A sealing system providing a pressure seal inlet and outlet for textile fabric webs between the interior of a high pressure chamber on which the system is mounted and a lower pressure zone such as the atmosphere, said system comprising a housing having first and second open end portions and at least one pair of opposed oppositely extending walls, said first open end portion communicating with the interior of said container and said second open end portion providing an inlet and an outlet for the webs supplied to the pressure chamber; and a plurality of sets of rollers mounted in said housing in sealing relation between said pair of opposed walls, and defining a plurality of separate pressure chambers in the housing through which the webs pass on their way into and out of said high pressure chamber; said sets of rollers including a first set of rollers mounted in said housing with their axis of rotation parallel and in spaced alignment with each other between said first and second ends of said housing; each of the rollers in said first set being covered by an elastic material; and a second set of hard rollers comprising a plurality of pairs of rollers respectively associated with at least one of said elastic rollers; the two rollers of each pair of hard rollers being located in laterally spaced parallel relation on opposite sides of their associated elastic covered roller and in contact therewith to form nips therebetween engaging a fabric web passed through the housing; said pairs of hard rollers also being located in spaced alignment to each other, parallel to said first set of rollers, between the inlet and outlet openings of said housing; and at least one of said pair of hard rollers contacting two of said elastic covered rollers to form two pairs of nips on opposite sides of said elastic covered roller whereby a series of pressure chambers are formed in said housing between the housing, an associated elastic covered roller and two hard rollers engaged therewith; and between two of said elastic covered rollers, said one pair of hard rollers and said housing, said pressure chambers having increasing pressure therein from the second open end of the housing to the first end thereof and said fabric web passing through said chambers on one side of said elastic covered rollers as it moves into the high pressure chamber and on the other side thereof as it moves away from the high pressure chamber.

2. A sealing system as defined in claim 1, including means for regulating the increase and decrease of the pressure in stages in the pressure stage chambers of the housing by the production of a counter pressure padding by means of compressed air.

3. A sealing system as defined in claim 1 wherein the rollers of said pairs of hard rollers are mounted for movement towards and away from each other; and means for resiliently biasing said rollers towards each otherand into contact with their associated elastic covered roller.

4. A sealing system as defined in claim 3 wherein said biasing means comprises generally semicylindrical inflated sleeves mounted in said housing adjacent said hard rollers on the sides thereof opposite the nips formed between the hard rollers and the elastic rollers whereby the biasing of said hard rollers into engagement with the elastic covered rollers is regulated by the inflated sleeves so that the nips between the rollers will be substantially pressure-tight.

5. A sealing system as defined in claim 4 including reducing valve means for regulating the pressure in the pressure chambers in said housing between the rollers.

6. A sealing device for sealing the common inlet and outlet opening of a high pressure chamber in which textile fabric webs are treated; said device comprising a housing mounted on said chamber in communication therewith and having a series of staged pressure chambers formed therein for providing a graduated pressure drop between one end of the housing adjacent the high pressure chamber and the opposite end of the housing; said housing having a pair of end walls, and said staged pressure chambers being formed between said end walls and a plurality of rollers rotatably mounted therebetween in sealing relation and in contact with each other to form gas and pressure tight nips therebetween to define said staged chambers; said rollers including a series of groups of rollers each of which includes at least one pair of laterally spaced hard rollers, and a roller covered with an elastic material positioned between the hard rollers in contact therewith on opposite sides thereby to form pressure tight nips on opposite sides of the elastic covered rollers for respectively engaging fabric moving into and out of said high pressure chamber and for sealing adjacent staged pressure chambers

Claims

3. A sealing system as defined in claim 1 wherein the rollers of said pairs of hard rollers are mounted for movement towards and away from each other; and means for resiliently biasing said rollers towards each other and into contact with their associated elastic covered roller.

6. A sealing device for sealing the common inlet and outlet opening of a high pressure chamber in which textile fabric webs are treated; said device comprising a housing mounted on said chamber in communication therewith and having a series of staged pressure chambers formed therein for providing a graduated pressure drop between one end of the housing adjacent the high pressure chamber and the opposite end of the housing; said housing having a pair of end walls, and said staged pressure chambers being formed between said end walls and a plurality of rollers rotatably mounted therebetween in sealing relation and in contact with each other to form gas and pressure tight nips therebetween to define said staged chambers; said rollers including a series of groups of rollers each of which includes at least one pAir of laterally spaced hard rollers, and a roller covered with an elastic material positioned between the hard rollers in contact therewith on opposite sides thereby to form pressure tight nips on opposite sides of the elastic covered rollers for respectively engaging fabric moving into and out of said high pressure chamber and for sealing adjacent staged pressure chambers from one another.