EP0489844B1 - Process and device for steaming yarn - Google Patents

Abstract

Process and device for fixing textile yarn (1) to be wound onto bobbins, using a vacuum bell (36) which can be evacuated and heated and which can accommodate one or a limited number of bobbins. Water and saturated steam are contained in a steam generator at a temperature equal to or slightly greater than the preselected temperature of the steam and at a pressure equal to the steam pressure at the vaporization temperature. The vacuum bell containing the bobbins is evacuated at a pressure substantially lower than the pressure of the steam. A control valve in a connecting line between the vacuum bell and the steam generator is then opened. As the vacuum bell is likewise preheated to essentially the vaporization temperature, the quantity of water required to fill the entire system with saturated steam at the vaporization temperature is very quickly converted to steam in the steam generator. The yarn is thereby steamed in cycles of approximately two minutes duration.

Description

The present invention relates to a method for steaming yarn according to the preamble of claim 1 and a device for steaming yarn according to the preamble of claim 11.

During the production and processing of textile yarns, latent tensions arise in the yarn, which cause the yarn to have a tendency to untwist and to form loops and loops. This behavior of the yarn is commonly referred to as curling tendency. The tensions arise primarily during spinning itself, but can also be caused by further processing, e.g. caused by winding operations and the like. The curling tendency significantly impairs the further processing of the textile yarn and must therefore be eliminated.

The yarns are usually steamed to remove the curling tendency, steaming taking place at temperatures between approximately 50 and approximately 150 ° C. The lower temperature range up to approx. 90 ° C is used more for wool yarns and the upper temperature range more for synthetic yarns. The quality requirements for the steaming process are very high because of uneven Vapors, for example, create tension threads in the fabric or the absorption of colorants in a dyeing process becomes uneven.

The steaming methods known in the prior art usually work with saturated steam. Wet steam can stain the yarn due to its condensate content, while superheated steam has poor heat transfer values. In order to have saturated steam available at temperatures below and above 100 ° C., the devices used for steaming must be such that the pressure prevailing in them can deviate upwards or downwards from the ambient pressure. Autoclaves are usually used for steaming, into which the yarn wound on bobbins together with the corresponding transport means, e.g. Yarn trolleys, twine boxes or pallets are introduced. An overview of such devices gives e.g. the DE-Z. "Melliand Textile Reports", Issue 9, 1987, page 684.

Steaming in the autoclave is often carried out under vacuum, a vacuum being created before the start of the steam supply, and in extreme cases the pressure is reduced to 0.1 bar absolute pressure. Vacuum steaming has the advantage that there is less air in the system, which makes steaming more uniform. The DE-Z provides an overview of vacuum steaming. "Melliand Textile Reports", Issue 5, 1966, pages 530-536.

The main disadvantage of steaming in an autoclave is that the largely continuous processing of yarn is interrupted by a time-consuming, discontinuous process. For example, the ring spinning process achieves a high output of spinning bobbins, which are tubes with a certain amount of yarn on each. Before these spinning bobbins are now fed to a continuously operating winding machine, they have to be collected in appropriate yarn trolleys and inserted into the autoclave. Then they have to be transported to the winding machine. The material flow required as a result not only requires extensive and complex devices, but also impairs the overall operating sequence of the spinning mill. Furthermore, since the autoclaves usually have to accommodate several yarn trolleys because of the processing capacity required, their dimensions are very large and therefore expensive, space-consuming and very unfavorable in terms of energy expenditure.

A while ago, DE-U 19 82 399 proposed a device in which steam is introduced into the interior of a perforated winding tube without the use of vacuum. A further development of this method is described in DE-A 36 01 099. Although this method allows the time and energy required for steaming to be reduced, it has the disadvantage that excessive condensation can occur here, which affects the uniformity of steaming. Yarn cores specially prepared for the process are also required. Such yarn tubes are more complex to manufacture than simple, cylindrical yarn tubes. In addition, e.g. the spinning mills are forced to replace their entire, expensive stock of bobbins using this method. The method has therefore not been able to establish itself in practice.

The present invention has for its object to provide a method for steaming yarn, by means of which a uniform steaming of the yarn is achieved with little expenditure of time and with little expenditure of energy. Furthermore, it is the object of the present invention to provide a device for steaming yarn, by means of which a uniform steaming of the yarn can be achieved with a low expenditure of energy and time and which requires only a small amount of space and construction. In particular, the method according to the invention and the device according to the invention should work in such short cycles that they can be included in a continuous process of yarn processing.

This object is achieved by the method according to claim 1. An apparatus for performing the method is the subject of claim 11.

With the method according to the invention, the possibility is created for the first time of performing a cyclical steaming of yarn with saturated steam in a wide temperature range.

This is achieved by subjecting only one or a small number of yarn packages to the damping and by using a vacuum bell which can be evacuated very rapidly in a short time. The evacuated vacuum bell is connected to a steam generator, in which water and saturated steam are enclosed at steam temperature and a pressure which essentially corresponds to the steam pressure of the water at the selected steam temperature, and the thermodynamic state variables in the vacuum bell are practically abruptly adapted to the State variables take place in the steam generator. The amount of water that is required to fill the vacuum bell with saturated steam of the steam temperature and the steam pressure defined for the respective temperature is very quickly converted into saturated steam in the steam generator.

Since the steam generator and preferably also the vacuum bell are largely kept exactly at the steam temperature, the amount of energy required for the evaporation does not lead to a significant drop in the temperature level. Keeping the temperature level constant is made considerably easier by keeping the vacuum bell correspondingly small. Compensation is particularly easy if, according to a preferred embodiment, the vacuum bell only receives a single yarn package. Furthermore, a decrease in temperature is avoided by regulating the temperature of the steam generator and preferably also the vacuum bell, by means of which temperature reductions are immediately compensated for.

Evacuating the vacuum bell before steaming takes about 20 seconds in a tested embodiment of the device according to the invention, while steaming itself takes about 90 seconds. As a result, the entire steaming can be carried out within a time cycle of approximately two minutes.

In order to prevent the colder yarn bobbin introduced into the vacuum bell from leading to an undesirable lowering of temperature or to excessive condensation of the introduced saturated steam, the sleeve and the yarn can, according to a preferred development of the invention, preferably be preheated by hot air before the vacuum bell is evacuated .

The vacuum bell is preferably ventilated after the steaming likewise with preheated hot air. This prevents an uneven temperature drop in the yarn.

According to a preferred development of the invention, the yarn is dried immediately after steaming. This can be done in the same bell in which the yarn was steamed. It is also possible to have a second one Provide vacuum bell that is used only for drying.

Drying is preferably carried out by evacuating the vacuum bell used for drying. Due to the then decreasing pressure in the bell, the vapor pressure of the water vapor on the yarn exceeds the ambient pressure, so that the majority of the vapor as superheated vapor is drawn off directly by the vacuum pump.

An evacuable condensation container is preferably provided, which is connected upstream of the vacuum pump. Cooling in the condensation container can ensure that the temperature prevailing there is below the temperature prevailing in the vacuum bell. Due to the thermodynamic laws, the steam from the vacuum bell then flows very quickly into the condensation container. The colder container thus acts like a powerful pump, through which the water vapor is drawn out of the vacuum bell.

The temperature of the condensation tank can be adapted to the desired vacuum end pressure. A vacuum end pressure of 20 mbar roughly corresponds to a saturated steam temperature of 17 ° C.

The device according to the invention is characterized by a structure whose external dimensions are only a fraction of the dimensions of a conventional autoclave. According to the invention, the device has a steam generator and at least one vacuum bell, which can be evacuated via a vacuum pump. The internal dimensions of the vacuum bell are adapted to the space requirement of one or more yarn packages. A corresponding one is used to regulate the temperature of the steam generator and / or the vacuum bell Control device is provided, which can preferably be combined with a control device which controls the entire sequence of the device. This control device is connected to a large number of temperature and pressure sensors, which detect the state variables in the individual system parts. The control device, which preferably has an arithmetic processor, operates according to a predetermined program and outputs control signals in order to control a number of control valves which are required to connect the vacuum bell, the vacuum pump and the steam generator to one another in the predetermined clock sequence.

Another very important advantage of the device according to the invention is the extremely low energy consumption. Due to the small dimensions and the short cycle times, the energy consumption, based on one yarn unit, is e.g. on a spinning cop, only a fraction of the effort required for autoclave damping.

For a constant quality of the damping, it is important that the steam temperature is kept essentially constant during the operation of the system. For this reason, it is desirable that at least the vacuum bell used for steaming is heated in such a way that the temperature of its inner wall essentially corresponds to the desired steaming temperature.

According to a first, preferred variant, this is brought about by electrical heating wires which are integrated in the vacuum bell and to which so much electrical energy is supplied that the desired temperature is reached.

According to a further preferred embodiment of the invention, the heating of the vacuum bells is brought about by integrating heating pipes into the vacuum bells through which a liquid, preferably water, flows. According to a preferred embodiment, the heating pipes are in flow communication with the water in the steam generator, e.g. with the help of a small circulation pump. It is thereby achieved that the water of the steam generator, the temperature of which is regulated very precisely in relation to the steam generation, flows through the vacuum bell and keeps it at the same temperature.

This version has the advantage that a control device for temperature control of the vacuum bell can be omitted.

As already explained in relation to the method, according to a preferred embodiment of the invention the same vacuum bell that is used for steaming is also used for drying. Drying takes place by connecting the vacuum bell to an evacuated vacuum container via a corresponding valve device, as a result of which the pressure in the vacuum bell drops rapidly. This removes moisture from the yarn package located in the vacuum bell.

The residual moisture that the yarn package in some applications requires for further processing can be determined beforehand within narrow limits by the choice of the negative pressure in the vacuum bell used for drying.

According to a further preferred embodiment of the invention, a different vacuum bell is used for drying the yarn package than for steaming. In this case, the device has at least two vacuum bells which are operated in cycles, the The bobbin is first steamed in the first vacuum bell and then dried in the second vacuum bell.

The system further preferably has a hot air generator in which air is preheated to a predetermined temperature, which is preferably equal to the steaming temperature, in order to use it for preheating and venting the vacuum bell.

As stated in the introduction, the device described above should preferably be set up for the cyclical processing of yarn packages. According to a preferred embodiment of the device according to the invention, the individual yarn packages are therefore placed on transport plates. This attachment can take place using handling devices known in the prior art, which are therefore not described in detail.

The transport plates slide in a slide rail which has a holding profile which corresponds to an inverted T, into which correspondingly designed parts of the plates engage. The plates have pins provided with one or more through bores, onto which the bobbin can be placed directly, and are arranged in the slide rail during continuous processing so that they are immediately adjacent. When the rearmost plate is pushed further, all other plates are therefore automatically moved forward by the corresponding displacement path.

A damping bell and a drying bell are then located above the slide rail and can be raised and lowered by a pneumatic device. Also newly developed sealing measures ensure that the vacuum bells automatically when pressed onto the plate are sealed against this. At this point, holes are also provided in the slide rail, which are also automatically sealed when the vacuum bells are pressed on. Through the holes in the slide rail, the vacuum bell or vacuum bells are connected to the steam generator, etc.

The plates with the yarn packages on them thus slowly move through the steaming and drying system, the cycle time in one exemplary embodiment for steaming or drying being approximately 2 minutes. The processing capacity is thus 30 bobbins per hour. If a larger processing capacity is required, several steaming and drying bells can be arranged in parallel. The slide rail then has a corresponding branching, and the incoming stream of plates with yarn packages is divided, for example, into four individual slide rails. With ten bells arranged parallel to one another, a processing capacity of 300 yarn packages per hour can then be achieved, which should be sufficient for most applications, but can be increased without problems by further parallel arrangements.

According to a preferred embodiment of the device according to the invention, the bells arranged in parallel are raised and lowered by a common device. By means of an appropriate arrangement of the slideways of the plates, which is described in detail in the subclaims and with reference to the figures, the cyclical steaming can then be carried out with very little space.

The device according to the invention can be designed so that it is suitable for any type of yarn package. In general, there are textile containers under the package to understand. These textile containers are usually produced by winding a textile yarn on sleeves, which consist, for example, of metal or plastic or the like. However, other container shapes are also conceivable. Experiments have shown that the method according to the invention works without problems even when yarn packages are used which have a high weight and / or large dimensions.

If, as in most cases, a rotationally symmetrically wound, essentially cylindrical yarn winding body is used and only one yarn winding body is processed for each vacuum bell, the interior of the vacuum bell is preferably also cylindrical.

Through the invention, the previous discontinuous steaming in an autoclave with all of its material flow problems is converted into a continuous process. Since the device is much smaller in size than an autoclave, the device can e.g. be arranged directly between a ring spinning machine and a subsequent winding machine.

Fig. 1

eine Schnittdarstellung durch eine Dämpfungs- oder Trocknungsglocke gemäß der vorliegenden Erfindung;

Fig. 2

ein Funktionsschema einer Dämpfungsvorrichtung gemäß der vorliegenden Erfindung;

Fig. 3

eine stark schematisierte Seitenansicht eines Ausführungsbeispiels der erfindungsgemäßen Vorrichtung (teilweise geschnitten), bei der insgesamt 20 Vakuumglocken zum taktweisen Dämpfen und Trocknen vorgesehen sind;

Fig. 4

eine schematisierte Aufsicht auf die Vorrichtung gemäß Fig. 3;

Fig. 5

eine Seitenansicht, welche den Hebe- und Senkmechanismus der Vakuumglocken zeigt;

Fig. 6

eine schematisierte Seitenansicht, welche den Transportmechanismus der Teller in der Vorrichtung gemäß Fig. 3 zeigt;

Fig. 7

eine Aufsicht auf den Transportmechanismus;

Fig. 8

ein alternatives Ausführungsbeispiel einer Vakuumglocke.

Further advantages and possible uses of the present invention result from the following description of an exemplary embodiment in connection with the drawing. It shows in a schematic way:

Fig. 1

a sectional view through a damping or drying bell according to the present invention;

Fig. 2

a functional diagram of a damping device according to the present invention;

Fig. 3

a highly schematic side view of an embodiment of the device according to the invention (partially cut), in which a total of 20 vacuum bells are provided for cyclical steaming and drying;

Fig. 4

a schematic plan view of the device of FIG. 3;

Fig. 5

a side view showing the lifting and lowering mechanism of the vacuum bells;

Fig. 6

is a schematic side view showing the transport mechanism of the plate in the device of FIG. 3;

Fig. 7

a supervision of the transport mechanism;

Fig. 8

an alternative embodiment of a vacuum bell.

An exemplary embodiment of the present invention is described below, in which two damping and drying bells are used for pulsed steaming of yarn.

The embodiment is designed for steaming yarn that comes from ring spinning machines and is wound on cylindrical metal sleeves or plastic sleeves. However, it should be pointed out that the device can of course also be used in the same way for all other types of yarns and yarn packages.

The yarn 1 schematically indicated in the drawing is on a cylindrical sleeve 2 made of plastic wound up, whereby a spinning cop 3 is formed. The spinning cop 3 is transported through the device with a plate 5, wherein it remains on this plate 5 even during the damping and drying process. The plate 5 is essentially rotationally symmetrical about an axis 6 and has a conical section 7 which is delimited at the top (ie towards the spinning cop) and at the bottom by a flat annular surface 8 or 9. Below this conical section there is a first cylindrical section 10 with a smaller diameter and then a second cylindrical section 11 with a larger diameter. A cylindrical pin 12 is arranged on the upper circular ring surface 8 and has a bevel 12a at its upper end (facing the spinning cop).

The outer diameter of the cylindrical pin 12 is slightly smaller than the inner diameter of the sleeve 2, so that the sleeve 2 can be pushed onto the pin 12 and is held by the latter. A cylindrical bore 13 arranged coaxially to the axis 6 runs through the plate 5, the purpose of which will be explained in detail below. The lower annular surface 9 also has a cylindrical extension 14.

The plate is made of metal, preferably aluminum.

The plate 5 is displaceably arranged in a slide rail 20, which is only shown in part in FIG. 1. The slide rail 20 has a guide groove 21 which extends essentially perpendicular to the plane of the drawing in FIG. 1. The guide groove 21 consists of an upper, narrower region 22 and a lower, further region 23. The guide groove 21 thus has the shape of an upside-down T in cross section. In the area of the guide groove shown in Fig. 1 is a cylindrical Bore 24 arranged, the function of which will be explained later. In the upper region of the slide rail 20, a recess 25 is provided, the width of which is slightly larger than the diameter of the cylindrical extension 14 of the plate 5. Four spring bodies 26 are embedded in the slide rail, essentially rotationally symmetrically to the axis of the cylindrical bore 24. The spring body 26 consist of a cylindrical hollow body 27, in the interior of which a spiral compression spring is arranged. The hollow body 27 is closed at its upper end with a flange 29, the diameter of which is slightly larger than the outer diameter of the hollow body 27. The spring body 26 is pressed into a cylindrical bore 28 in the slide rail 20 and is axially connected to the flange 29 by the flange 29 Fixed slide rail. In the interior of the hollow body 27, a ball 30 is also provided, which is pressed upwards by the spring. If the spring body 26 is loaded with a predetermined load, the ball 30 is inserted into the hollow body 27. An annular sealing groove 32 is also provided concentrically with the cylindrical bore 24 of the slide rail. A commercially available O-ring 33 is embedded in this sealing groove 32.

The bell 35 has a substantially cylindrical metal body 36 which is closed at the bottom by a flange 37. On the flange 37, an upward-pointing cylindrical web 38 is arranged concentrically to the longitudinal axis 39 of the bell.

The cylindrical metal body 36 of the bell is closed at the top by an arched cover 41 formed integrally therewith. Two threaded connectors 42 and 43 are arranged in the cover 41, offset with respect to the longitudinal axis 39 of the bell. A pressure sensor 44 is screwed into the first, shorter threaded connector 42 and a temperature sensor 45 in the second, longer threaded connector 43.

The cylindrical metal body 36 of the bell is surrounded by a heating wire 55. Furthermore, the bell has an insulation 56 which is intended to largely prevent heat transfer from the cylindrical metal body 36 to the ambient air.

On the underside of the flange 37, on the surface facing the plate 5, concentrically to the longitudinal axis 39 of the bell, there is an annular recess 57 in which a second O-ring 58 is arranged.

The function of this bell is now as follows: the bell can be raised and lowered along its longitudinal axis 39 by a pneumatic cylinder. The bell is initially in the raised state, and the spinning cop 3 located on the plate 5 is brought into a position in which the bore 13 of the plate 5 lies above the bore 24 in the slide rail 20. The bell is then lowered and pressed onto the plate 5. The contact pressure of the bell 5 is transmitted to the spring body 26, whereby the balls 30 are pressed into the hollow body 27 thereof. As a result, the second cylindrical section 11 of the cylinder 5 lies firmly on the first O-ring 33. The second O-ring 58 simultaneously seals the flange 36 of the bell from the plate 5, so that the bell is connected to the bore 24 in an airtight or vapor-tight manner.

The spring body 26 causes the plate 5 to be pushed onto the O-ring 33 at a vertical distance from the latter. This prevents damage to the O-ring 33 when the plate 5 is pushed. If the plate 5 is not in the position shown in FIG. 1, the cylindrical extension 14 of the plate lies directly on the Slide on. As a result, any wear when the plate 5 slides is limited only to the area between the cylindrical extension and the slide rail. The lower circular ring surface 9 itself and the upper circular ring surface 8, which should keep their original state as far as possible with regard to the sealing or the contact with the spring bodies, are not changed by wear.

2 shows a functional diagram of the device for steaming yarn according to the invention. In this device, a bell 36 is used as the first bell 71 for steaming, and a bell 36 as the second bell 72 for drying. The structure of both bells is identical and corresponds to that of bell 36 described with reference to FIG. 1.

As can be seen in FIG. 2, the plates 5 shown schematically slide on the slide rail 20, also shown schematically.

The device has a steam generator 73, a condenser 74 and a hot air generator 75.

The first bell 71, the second bell 72, the steam generator 73, the condenser 74 and the hot air generator 75 are each designed to withstand both a high negative pressure (up to 20 mbar absolute pressure) and a higher positive pressure (up to about 5 withstand absolute pressure). The upper design value of the system is essentially determined by the maximum treatment temperature of the yarn. If, for example, only a temperature of 120 ° C is to be achieved, a maximum pressure of 2 bar absolute (corresponding to the steam pressure of the water at 120 ° C) is sufficient, only temperatures below 100 ° C used, the system only has to be dimensioned in relation to the necessary negative pressure.

The steam generator 73 is essentially designed as a cylindrical container which is sealed in a pressure-tight manner and which is insulated against heat loss via its outer surfaces. The steam generator 73 is connected via a feed pump 76 and a valve 77 to a water supply network shown schematically at 78. The volume flow of the pump, which operates as required, is fed to the steam generator 73 via a line 79.

The steam generator also has a heating element or heating coil 80, by means of which the water in the steam generator can be heated.

The water level of the steam generator is monitored by a fill level sensor 81, the pressure by a pressure sensor 82 and the temperature by a temperature sensor 83.

The steam generator 73 is connected to the other system parts via a line 87 which is arranged at its uppermost end.

The condenser 74 also has a substantially cylindrical body which is sealed pressure-tight and which has an external insulation to reduce the heat transfer to the environment. The condenser 73 is connected to a vacuum pump 92 via a line 91. Furthermore, a cooling device 93 is provided which cools a cooling medium which flows through feed lines 94, 95 into a schematically indicated cooling spiral 96 within the condenser 74.

A drain line 97 with a valve 98 is provided on the underside of the condenser 74.

The condenser is connected via a line 100 both to the steam supply device for the damping bell 71 and to the steam generator 73, a plurality of valves being provided through which these connections can be controlled and regulated in detail.

The hot air generator 75 is also designed to be pressure-resistant and thermally insulated from the environment by means of insulation. A heating coil 106 is provided to heat the air in the hot air generator.

The line system for connecting the various devices of the damping system essentially has three main lines, namely a first main line 111, a second main line 112 and a third main line 113. The main lines 111 and 113 are connected to the line 87 of the steam generator 74. The main line 111 is also connected to the hot air generator 75 via corresponding valves, as explained below. The second main line 112 is open at one end to the environment and is connected at its other end to the main line 111 in front of the hot air generator 75. The third main line 113 is also connected to the line 87 coming from the steam generator 73 and is connected on the other side to the line 100 leading to the condenser 74. The first main line 111 and the second main line 112 are connected to one another via a connecting piece 115, which continues to lead to the bore 24 of the slide rail in the region of the damping bell 71. The main line 111 is also connected via a line 117 to the bore 24 'of the slide rail in the area of the drying bell 72, this line on the the other side is open to the environment via a valve 118.

The operation of the device is controlled and regulated by a control unit 130. The control unit 130, a process computer which e.g. can be constructed on the basis of one of the known microprocessors, receives the signals from all sensors and gives the control signals with which the heating of the bells 71, 72, the steam generator 73 and the hot air generator 75 and the cooling of the condenser 74 is controlled - or control signals for all valves and the control signals for the movement control of the plate 5. The entire control and regulation takes place via a program stored in the control unit 130. An operator can set the desired control parameters, i.e. above all, the temperature at which steaming is to be carried out using a suitable data medium, e.g. insert a floppy disk, a tape, a punched tape or a keyboard into the control unit.

The function of the exemplary embodiment described with reference to the figures is explained in detail below, with steaming at 80 ° C. being assumed as an example.

As described above, the entire function of the system is controlled by the control device 130. The data required for steaming, ie essentially the steaming temperature and steaming times, are either predefined in the control unit or, as described, are read into the control unit before starting. The operation of the system begins with a preheating cycle in which the temperature of the bells and the temperature of the steam generator etc. are brought to the predetermined steam temperature. This heating process also causes the water in the steam generator 73 to reach the desired level Temperature heated. At the same time, the condenser is evacuated to an absolute pressure of approx. 20 mbar via the vacuum pump 92.

The absolute pressure of 20 mbar corresponds to the vapor pressure of water at around 17 ° C. Since the usual steam temperatures are significantly higher, this ensures that the saturated steam pressure of the water used for steaming is always above this value. E.g. used to steam wool yarn a temperature of 80 ° C, the steam pressure of the water is 473 mbar.

To set this pressure in the steam generator, a valve 141 in the main line 113 is briefly opened so that the steam generator (still under normal pressure) and the condenser (with 20 mbar absolute pressure) are connected to one another. As a result, the absolute pressure of the system drops to a value that is initially far below 473 mbar. Since the steam pressure of the water at 80 ° C is above this pressure value now prevailing in the steam generator, so much water is practically converted into steam that the saturated steam pressure of 473 mbar is established. The prerequisite for this is that the temperature level in the entire system is kept at 80 ° C. As already stated above, this is achieved in that all essential parts of the system are constantly kept at this temperature.

The steam generator 73 now contains water at 80 ° C. and steam at 80 ° C. at a pressure of 473 mbar. After this preparatory measure, the first spinning cop 3 can be conveyed on the plate 5 via the slide rail 20 under the steaming bell 71. The pneumatic actuating devices of the steam bell lower the steam bell and press it onto the plate 5. The balls 30 are pressed into the hollow body 27 of the spring body 26, and a tight seal between the bell and plate and plate and slide rail is achieved via the O-ring seals 33 and 58. A valve 142 in the first main line 111 is then opened, as a result of which the interior of the steam bell is connected to the condenser 74 via the bore 24. In the meantime, the initial vacuum of 20 mbar absolute pressure has been restored in the condenser 74 by the vacuum pump 92. This ensures that a corresponding vacuum of likewise approximately 20 mbar can be generated in the steaming bell and in the yarn package in a very short time, which is generally less than 20 seconds. The valve 142 is then closed again and the valves 144 and 145 are opened. The valve 145 is designed as a needle valve and can therefore be regulated in a particularly metered manner. The bell 71 is now connected via the main line 111 and the line 87 to the steam generator 73, in which a temperature of 80 ° C. and a saturated steam pressure of 473 mbar prevail. It should be pointed out that the damping bell 71 is constantly kept at this temperature by the heating systems and by the temperature sensors. The saturated steam enters the bell 71 through the bore 24 and the hollow sleeve 2. It should be noted that the sleeve 2 of the spinning cop 3, which is shown in the figure, is not perforated. Rather, the steam enters the bell bell 71 on the upper open side of the sleeve.

Since the steam bell was previously evacuated and there is therefore very little air between the individual layers of the yarn, the steam can reach all layers of the yarn unhindered.

Furthermore, since the inner wall of the damping bell and the other parts of the system have a temperature that corresponds to the saturated steam temperature, steam condensation on these surfaces is avoided.

If, in some applications, the temperature difference between the sleeve of the yarn is still too high after the yarn has been introduced into the damping bell and after the evacuation, the sleeve can be preheated by briefly opening a valve 146 to the hot air generator before the bell 71 is evacuated. As a result, hot air flows into the damping bell via the main line 112 and heats the sleeve and the yarn. Since the supplied hot air is kept at the temperature level of the saturated steam temperature, i.e. in the example at 80 ° C, the hot air supply does not cause overheating. This effectively prevents the condensation of the steam in a sleeve that is too cold.

After steaming, which in the present case can take, for example, 90 seconds, valve 146 is opened again and the steaming bell is thereby ventilated with hot air. Since the hot air is at the same temperature as the steam temperature, there is no re-steaming. Then the bell 71 is raised and the spinning head is conveyed further with the transport plate 5 and comes into a position under the drying bell 72. The drying bell 72 is moved up and down simultaneously with the damping bell and is sealed off from the slide rail in the same way as in the case of the Damping bell 71 is the case. The spinning head is in the closed drying bell after the next lowering process. As soon as the evacuation of the damping bell 71 has ended, a valve 148 is opened while at the same time the valve 142 is closed. As a result, the drying bell 72 is connected to the condenser 74. The steam is now pumped out via the vacuum pump 92. At the same time, the drying bell is heated via its heating system so that the evaporation does not lead to an inadmissible temperature reduction.

It should be pointed out that it is also possible in the meantime to supply hot air from the hot air generator 75 into the drying bell in order to keep the temperature at a desired level.

As tests have shown, the drying time is approximately 2 minutes in order to achieve a desired, uniform and reproducible residual moisture in the yarn, which enables the yarn to be processed immediately.

After the drying process has ended, both bells are raised again, and the previously steamed amount of yarn is transferred to the drying bell, while the dried amount of yarn is processed, e.g. can be fed to a winding machine.

It is pointed out that it is also possible to add chemicals to the water in the steam generator if it is desired to influence the damping process accordingly.

An embodiment of a pulsed damping and drying device, which works with a total of ten vacuum bells for steaming and ten vacuum bells for drying, will now be described with reference to FIGS. 3 to 7.

3 schematically shows a conveyor belt 200, as is known in the prior art, in order to convey spinning bobbins or similar yarn packages. The conveyor belt 200, which is deflected via a roller 201, has pins 202 on which the spinning heads 3 are placed.

In the central part of FIG. 3, a total of four rows of vacuum bells can be seen in a sectional representation, a first row 207, a second row 208, one third row 210 and fourth row 211. Rows 207, 208 are bells used for steaming, while rows 210, 211 contain bells used for drying. As can be seen in the top view in FIG. 4, a total of five damping bells 209 and a total of five drying bells 212 are arranged in each row. In the left part of FIG. 3, a second conveyor belt 205 is provided, which is designed in the same way as the conveyor belt 200.

As shown in the top view in FIG. 4, a slide rail system 220 is arranged in the central area of the device, which in the exemplary embodiment shown consists of five transverse slide rails 221, 222, 223, 224 and 225 and four longitudinal slide rails 231, 232, 233 and 234 as well consists of two curved slide rails 235, 236, the curved slide rails connecting the longitudinal slide rails 231, 232 to the longitudinal slide rails 233, 234.

The slide rails are all designed as has been explained with reference to FIG. 1. Plates move on the slide rails, as were also explained with reference number 5 with reference to FIG. 1.

The function of the device is now as follows: A handling device (not shown), which is known in the prior art, converts the spinning heads conveyed by the conveyor belt 200 onto the plates 5. 4 with respect to the first four plates, which are located on the slide rails 231 and 232, this process has already been completed. On the other hand, the fully steamed and dried spinning cops, which are located on the slide rails 233, 234, are placed on the conveyor belt 205 by means of a corresponding handling device. As soon as two spinning heads are removed from the slide rail 233, 234, the plates 5 are moved on the two slide rails by one plate division (this is the diameter of a plate) in the direction of the slide rails 231, 232. As a result, two empty plates are fed to the handling device for placing the spinning heads, and two full plates come into the area of the handling device for removing the spinning heads and for placing on the belt 205. As soon as the slide rails 231, 232 are filled, a total of ten spinning heads are opened 10 plates are located, the ten spinning heads can be pushed to the left by the sliding device 240 in the illustration according to FIG. 4.

The sliding device 240 consists of a transversely arranged rod 241 which can be moved towards and away from the slide rails via a double-acting cylinder 242 (pneumatically or electrically operated).

As soon as the cycle time for steaming or drying the previously processed cops has ended, the control device outputs a signal and the steam bells and the drying bells are lifted off. The slide device 240 pushes all the plates on the slide rails 221, 222, 223, 224 and 225 by two plate divisions to the left. As a result, these ten plates are pushed under the vacuum bells 207, 208 used for damping. At the same time, the plates previously located under the steam bells are shifted to the left by two plate divisions (in FIG. 4), so that they are now under the drying bells. The plates previously located under the drying bells are pushed onto the slide rails 233, 234. The steaming and drying bells are then lowered and the steaming and drying process begins. During this process, the finished ones on the slide rails 233, 234 are finished Spinning heads removed from the plates and unprocessed spinning heads placed on the plates conveyed on the slide rails 231, 232. After two minutes, the steaming process is complete, and the steaming bells and the drying bells are raised again and the now steamed heads are pushed under the drying bells. At the same time, the newly filled plates are pushed under the steaming bells and the bells are lowered again. After about two minutes the drying process is complete and the plates are then pushed out on the slide rails 233, 234 in the next cycle, where the spinning heads are removed.

A total of ten spinning bobbins are processed with a cycle time of two minutes, which results in a total capacity of the plant of 300 spinning bobbins per hour. Each spinning cop is located (maximum) eight minutes in the area of the device.

FIG. 5 shows a detail of the device according to FIGS. 3 and 4, namely the mechanism for raising and lowering the bells. As can be seen in FIG. 5, the slide rails 231 etc. are arranged at a distance above a floor surface. Below the slide rails are two cylinders 250, 251 which have extendable piston rods 252, 253. Parallel to the arrangement of the slide rails is a support device 254, which is fixedly connected to the piston rods 252, 253 and is arranged essentially horizontally. The twenty vacuum bells are attached to this support device 254, as can be seen in the top view of FIG. 4.

Fig. 6 shows a further detail of the device, namely the mechanism for moving the plates. The plates have, as has been explained with reference to FIG. 1, a bore 13 through which, for example, during the damping of the Steam is supplied. This hole is also used to move the plates. For this purpose, a longitudinal cylinder 260 is provided, which is arranged horizontally and parallel to the slide rail 234. A short-stroke cylinder 261 is arranged with its piston rod 262 perpendicular to the direction of displacement of the longitudinal cylinder 260. The short-stroke cylinder 261 is now actuated to move the plates, so that its piston rod 262 engages in the bore 24 of the spinning cop 3. The plate is then moved on by one plate division, whereby at the same time all other plates abutting this plate are also moved.

Fig. 7 shows a top view of the transport device according to Fig. 6. It can be seen that e.g. the slide rail 234 has a longitudinal slot 270 in the drive area, into which the piston rod 262 of the short-stroke cylinder 261 engages. The longitudinal slot allows the piston rod to move in the slide rail in the desired manner.

8 shows a further exemplary embodiment of the present invention. In this exemplary embodiment, the vacuum bell 280 is essentially eight-shaped, ie it has two mutually merging inner wall surfaces, each with a circular cylindrical diameter. The axes of two spinning heads 3 are arranged coaxially to each of these circular cylinder cross sections. In this embodiment, two spinnerets can therefore be accommodated per vacuum bell, although the total volume of the vacuum bell is still very small in relation to the number of spinnerets introduced, and an exact alignment of the position of the spinnerets to one another and of the spinnerets to the inner wall of the vacuum bell is also provided. As a result, reproducible damping of the yarn is also possible with this device.

The embodiment described above is installed between a ring spinning machine and a winding machine.

Claims (32)

1. Process for fixing textile yarn wound onto bobbins by way of steam saturated at a preselected temperature using a vacuum bell for receiving the textile yarn which can be heated and evacuated by a vacuum pump, and a steam generator, characterised by comprising the steps of:
   pre-heating the steam generator and a quantity of water contained therein to a temperature equal to or slightly greater than the preselected vapourisation temperature;
   evacuating the steam generator to an absolute pressure which essentially corresponds to the steam pressure of the water at the preselected vapourisation temperature;
   supplying the vacuum bell with one or a limited number of bobbins having a predetermined spaced arrangement with respect to the inner wall, and also with respect to one another for more than one bobbin;
   evacuating the vacuum bell to an absolute pressure which essentially lies below the steam pressure of the water at the preselected vapourisation temperature;
   opening a valve in a connecting line between the steam generator and the vacuum bell;
   steaming the yarn with the saturated steam flowing into the vacuum bell;
   steaming the yarn with the saturated steam flowing into the vacuum bell;
   ventilating the vacuum bell; and
   taking out the bobbin(s).
2. A process in accordance with claim 1, characterised in that, the vacuum bell is also pre-heated to a temperature which is essentially equal to the preselected vapourisation temperature.
3. A process according to any one of claims 1 or 2, characterised in that, the step of ventilating the vacuum bell after the steaming step is carried out with pre-heated hot air.
4. A process in according to any one of claims 1 to 3, characterised in that, the yarn is dried after the steaming step.
5. A process according to claim 4, characterised in that, the drying of the yarn is carried out under vacuum in an evacuatable vacuum bell.
6. A process according to claim 5, characterised in that, during the step of drying, the inner space of the vacuum bell which serves to carry out the drying of the yarn is connected via a closable connecting line with the inside of a condensation-container which can be evacuated and cooled.
7. A process according to any one of claims 1 to 6, characterised in that the same vacuum bell is used for the steps of steaming and drying.
8. A process according to either of claims 5 or 6, characterised in that, the step of steaming is carried out in cycles using at least two vacuum bells such that the bobbin is at first steamed in the first bell and then introduced into the second bell in which it is dried.
9. A process according to any one of claims 1 to 8, characterised in that for every respective steaming-cycle and respective drying-cycle a bobbin is received within a bell.
10. A process according to any one of claims 1 to 9, characterised in that, the dwelling time for the bobbin(s) in the steaming bell and/or the dwelling time for the bobbin(s) in the drying bell amounts to less than 300 seconds, preferably less than 150 seconds.
11. A device for fixing textile yarn wound onto bobbins by way of steam saturated at a preselected temperature comprising a vacuum bell for receiving the textile yarn which can be heated and evacuated by a vacuum pump, and a pressure-resistent, heatable steam generator,
    characterised in that the inner dimension of the vacuum bell (36,71) accomodates one or a limited number of bobbins (3); and by further comprising
    a heating device including a temperature regulation means which keeps an amount of water contained in a steam-container at a temperature level corresponding to around the vapourisation temperature; and by comprising
    a pressure regulating device for controlling the pressure in the steam generator by way of a vacuum pump at a value corresponding essentially to the steam pressure of the water at the preselected vapourisation temperature; and by comprising
    at least three control valves whereby a first control valve is arranged in a connection line between the vacuum pump and the vacuum bell, a second control valve in a connection line between the vacuum bell and the steam generator and a third control valve in a ventilation line for the vacuum bell; and by further comprising
    a control device for controlling the function of the control valves which causes initially the first control valve to be opened during which the second and third control valves are closed, then for the second control valve to be opened during which the first and third control valves are closed, and then for the third control valve to be opened during which the first and second control valves are closed.
12. A device according to claim 11, characterised in that, sensors for measuring pressure and temperature are provided in the vacuum bell and in the steam generator, and that the control device carries out the opening and closing of the control valves after a predetermined time-interval taking into account the measured temperature and pressure values.
13. A device according to claim 12, characterised in that, the control device also produces an output signal which acts on the temperature regulation and the pressure regulation of the steam-container and/or the vacuum bell.
14. A device according to any one of the claims 11 to 13, characterised in that an evacuatable container is provided between the vacuum pump and the vacuum bell which is connected with the vacuum bell via the first control valve.
15. A device according to claim 14, characterised in that the evacuatable container is formed as a condenser and comprises a cooling device as well as a water-draining valve situated in the lower region of the container.
16. A device according to any one of claims 11 to 15, characterised by further comprising a heatable container which serves to produce hot air and which is connected to the third control valve via a connection line.
17. A device according to any one of claims 1 to 16, characterised by further comprising at least a second vacuum bell in which the steamed yarn is to be dried.
18. A device according to claim 17 or one of claims 14 or 15, characterised in that, the vacuum bell which serves for drying is connected to the evacuatable-container via a connecting line and a fourth control valve.
19. A device according to any one of claims 11 to 16 or 18, characterised in that the vacuum bell to be used in steaming is also to be used for drying.
20. A device according to any one of claims 11 to 19, characterised in that, each vacuum bell is formed so as to receive a single bobbin.
21. A device according to claim 20, characterised in that, the bells for steaming and/or the bells for drying are formed as cylindrical bodies having essentially a cylindrical inner area, and by further comprising a holding apparatus by which the bobbins are held essentially coaxial with the cylindrical axis of the holder.
22. A device according to claim 21, characterised in that, the holding apparatus is built as a transporting plate (5) which includes a stud having one or more through-holes, the stud being arranged essentially vertical in the functioning position and whose outer diameter matches the inner diameter of a collar (2) on which the textile yarn is wound.
23. A device according to any one of claims 11 to 22, characterised in that each vacuum bell can be raised and lowered.
24. A device according to claim 22 or 23, characterised in that the transporting plate for receiving the bobbins is guided on a slide rail (20) and that sealing means are provided which create a seal between the vacuum bell and the plate when the vacuum bell is to be lowered onto the plate.
25. A device according to claim 24, characterised in that the slide rails comprise a bore which is connected with the through-hole(s) of the stud of the plate when the plate is placed in a predetermined position under the vacuum bell.
26. A device according to claim 25, characterised in that resilient means are arranged in the slide rails or in the transporting plate which hold the transporting plate over the sliding rails with a predetermined distance and that a seal is provided between the leading bore of the sliding rails and the inside of the stud of the plate which seals if the plate is pressed against the slide rails due to the vacuum bell opposing the resilient force of the resilient means.
27. A device according to any one of claims 11 to 26, characterised in that, a number of vacuum bells are provided which by means of a common carrier apparatus are connected together and which can also be lowered and raised together.
28. A device according to any one of claims 24 to 27, characterised in that, at least two slide rails are arranged parallel to each other.
29. A device according to any one of claims 24 to 28, characterised in that, a system of slide rails is provided which comprises of a first region in which the bobbins are placed onto the transporting plate, a second region in which the bobbins in the vacuum bell(s) are to be steamed and when applicable also dried, a third region in which the bobbins are to be taken from the transport plates, and a forth region in which the transporting plates from the third region of the slide rail system are to be returned to the first region.
30. A device according to any one of claims 11 to 29, characterised in that, an apparatus is provided for heating the vacuum bell(s).
31. A device according to claim 30, characterised in that, the heating of the vacuum bell(s) is carried out by an electric heating device arranged in the bell(s) which is regulated by the control means.
32. A device according to claim 30, characterised in that the heating of the vacuum bell(s) is carried out by heating tubes through which water runs and which are arranged in the bell(s) whereby the heating tubes are placed in a current connection with the water contained in the steam generator.

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