A JIGGER FOR DYEING A WEB OF FABRIC

Abstract: A jigger for dyeing a web of fabric comprises two main rollers (1, 2). The web of fabric is alternately wound on and unwound from said main rollers. The main rollers (1 and 2) are driven by a common motor (12) through a variable gear (14) adapted to adjust the speed of rotation of each main roller (1, 2) in such a manner that the web of fabric is wound thereon and unwound therefrom at a substantially constant fabric tension. An intermediary gear (17, 18) is provided between the variable gear (14) and each of the two main rollers (1, 2), said intermediary gear in a coupled position reducing the output speed of the variable gear (14) and in a decoupled position transferring said speed unchanged directly to the main rollers (1, 2).

Description: Title: A iip^er for dyeing a web of fabric Technical Field The invention relates to a jigger for dyeing a web of fabric and comprising two main rollers, where the web of fabric is alternately wound on and unwound from said main rollers, said jigger further comprising two guide rollers, about which the web of fabric is passed through a dye bath, and whereby the main rollers of the jigger are driven by driving means through a common variable gear adapted to adjust the speed of rotation of each main roller in such a manner that the web of fabric is wound thereon and unwound therefrom at a substantially constant fabric tension. Background Art Jiggers are known where the main rollers are driven se¬ parately by a variable gear. The variable gear is adapted to adjust the speed of rotation of the main rollers such that the web of fabric is wound on and unwound at a sub¬ stantially constant fabric tension. Such a jigger involving a direct driving of both main rollers requires, however, a very sensitive and primarily a very quickly reacting adjustment system. The latter requirement applies especial¬ ly to the starting up of the jigger whereas the usual un¬ winding and winding process requires nothing but a con- tinuous alteration of the exchange ratio of the variable gear supplemented with an adjustment of a possible un¬ balance in the rolls of fabric. When the jigger is to be loaded with a new web of fabric, the completely dyed web of fabric is removed from one main roller whereafter the new web of fabric is wound thereon. During the latter procedure, the second main roller and possibly also the variable gear are idle. The variable gear can for instance be locked in a specific position or be controlled by the travelling speed of the web of fabric. When the winding or the dyeing process is to be started, the variable gear may ther.efore be adjusted in an incorrect position, which in the worst case may cause the main roller with the web 5 of £sbric to start at the highest speed simultaneously with " the second main roller starting at the lowest speed. The ^ Mow space conditions in the dye bath present very poor possibilities of collecting or releasing fabric by means of A compensating device. Accordingly, it is of 10 major importance that the relative speeds of the main rollers can be correctly adjusted in a few seconds. i Attempts have been made at overcoming this problem by means of a ^ driving motor starting at a low speed. In this . manner the amount of unwound web of fabric is reduced and "* 15 time is insured for the adjustment. The variable gear moves, however, simultaneously at a low speed and is " " herefore difficult to adjust. Accordingly, only very few gears ar suitable for this purpose, said gears being easily overloaded or damaged by the quick adjustment 20 required. DiscltOffure of Inveittion > The ofeje t of the invention is to provide a jigger allowing su^ch . quick adjustment simultaneously with allowing the variable gear to move at a usual speed while being adjust- 25 ed_ to the eorrect position. The jfgger according to the invention is characterised in that an intermediary gear is provided between the variable gear and ?each of the two main rollers, said intermediary gear redttaijng in a first position the output speed of the 30 variable gear and in a second position reducing said output ' speed of said variable gear to a minor degree or transfer- ring said, speed unchanged directly to the main rollers. In this manner the main rollers and the web of fabric are allowed to move relatively slowly simultaneously with the variable gear and the driving means moving at a usual speed while adjusting themselves correctly to achieve the desired measured fabric tension without too much fabric being col¬ lected or released in the dye bath. The latter procedure takes place while the intermediary gears are in their first position. Usually it takes from half a minute to a minute for the variable gear to adjust from one outer position to the other outer position, and consequently it is possible to adapt the control system of the jigger so as to adjust the intermediary gears to the second position according to a predetermined period of time. The adjustment of the intermediary gears is suitably carried out simul- taneously, and the positioning of the intermediary gears in the first position is suitably automatic when the winding or dyeing process is stopped. Fixed gears may, if desired, be provided between the driving means and the main rollers in addition to the intermediary gears and the variable gear. According to a particularly advantageous embodiment of the invention each intermediary gear may comprise an input shaft and an output shaft arranged in mutual coaxial relationship and being fixedly connected to an input gear wheel and an output gear wheel, respectively, said gear wheels co-operating with one or more sets of intermediary gear wheels, where each set of intermediary gear wheels comprises two- intermediary gear wheels interconnected by means of an intermediary shaft, which is rotatably mounted in a common housing, and the housing may comprise two first coupling devices and a second coupling device alter¬ nately coupling the housing to the input shaft and the output shaft of the intermediary gear and to the frame of the jigger. In addition according to the invention the intermediary gears may be adapted to be gradually coupled in so that they can secure a gradual braking or acceleration of the main rollers, which inter alia can be utilized when it is desired to stop said gears at the termination of the dyeing ,5 process. Finally according to the invention the intermediary gears may be adapted to be arranged in a position where the connection with the shafts of the main rollers is de¬ coupled, whereby the common motor can be used for driving 10 one of the main rollers when a completely dyed web of fabric is to be replaced by a new web of fabric. Brief Description of the Drawing The invention is described in greater detail below with reference to the accompanying drawing, in which 15 Fig. 1 is a diagrammatic side view of a jigger according to the invention, Fig. 2 is a diagrammatic view of the two main rollers of the jigger as well of the connection of said rollers with <£- the driving motor through their respective intermediary 20 gear, a d a common variable gear, Fig. 3 is a diagrammatic view of an embodiment of a va¬ riable gear of a conventional type, and Fig.. 4 is a diagrammatic, sectional view through a pre¬ ferred embodiment of an intermediary gear to be used in 25 the jigger accαrding to the invention. Best Mode for Carrying Out the Invention The jigger of Fig. 1 comprises two main rollers 1 and 2 and two giiide rollers 4 and 5 situated in a dye bath 3. A pendulum roller 6 is situated between and on a level above the guide rollers. The pendulum roller is mounted on a lever bar 7 suitably biased by means of a spring 8 and is connected to a potentiometer 9 registering its angular position about a point of rotation 10. The two main rollers 1 and 2 carry a web of fabric 11 passing downwards into a dye bath 3. In the dye bath 3 the web of fabric continues about the two guide rollers 4 and 5 through the intermediary pendulum roller 6. The pendulum roller 6 ensures by means of the spring 8 that the web of fabric 11 possesses a suitable tension. The potentiometer 9 registers the angular position of the lever bar 7 in such a manner that the mutual speed of rotation of the main rollers 1 and 2 is adjusted in a conventional manner when the angular position exceeds a predetermined limit. The web of fabric 11 travels during the conventional dyeing process from one main roller to the other main roller and back again a predetermined number of times, and during this procedure the main rollers 1 and 2 are driven at their respective speed so that the tension of the web of fabric 11 is kept substantially constant. The registering of the tension may, if desired, also be carried out in other conventional ways beyond the one by means of the potentiometer 9. As illustrated in Fig. 2, thi main rollers 1 and 2 are driven by means of a common motor 12. The output shaft 13 of the common, motor communicates with a common variable gear 14 comprising two output shafts 15 and 16 which are connected to their respective main roller 1 and 2, respec- tively, through their respective intermediary gear 17' and 18' , respectively. The variable gear 14 is of a conventional type like the one shown in Fig. 3 which is called a winding gear. The variable gear 14 comprises two parallel steel discs 17' and 18' fixed.ly connected to the respective output shafts 15 and 16 of the variable gear. The steel discs 17' and 18' are sitύat d parallel to one another and are pressed against an -intermediary roller 19 connected to the output 5 shaft 13 of the motor 12. The discs 17' and 18' are mutual¬ ly displaced such that their axes of rotation extend p rallelly with a distance therebetween. When the output shafts 13 of the motor is rotating, the roller 19 rotates and consequently the discs 17' and 18' are caused to rotate -10 too a% a speed depending on the radial positioning of the roller 19 pelative to each of the two discs 17' and 18' . * - The radial^position of the roller 19 is, as indicated by means of an arrow 20, adjustable by displacement of the jro-ller 19 in axial direction. The displacement is caused 15 by t έ measurement - of the potentiometer 9 of the angular position of the lever bar 7 as well as by the desired Λ ( speed ' of the web of fabric, the latter speed usually being ^desired - o be maintained constant. The displacement of the rfeller 19 is carried out in a manner not described in 20 greafe r detail, and the guiding is carried out in a conven¬ tional manner by means of a control unit 21 in response £jo t signals received from various sensors , such as the potentiometer 9 * 5 As previously mentioned, an intermediary gear 17 and 18 25 is provided between the variable gear 14 and each of the two main rollers 1 and 2, whereby the output shafts 15 and 16 of Che variable gear 14 represent the input shaft , ■ aE the respective intermediary gears 17 and 18. The embodiment of Fig. 4 of an intermediary gear 17 com- " 30 prisβ thus an input shaft 15 as well as an output shaft 22 directly communicating with the main roller 1 in ques¬ tion. The Input shaft 15 and the output shaft 22 are coaxi lly arranged relative to one another and are con- necte^l to ,&n input gear wheel 23 and an output gear wheel , $ - 5 24, respec€ively. These two gear wheels 23 and 24 are interconnected by means of a set of intermediary gear wheels 25 and 26, each set comprising two intermediary gear wheels 27 and 28 and 29 and 30, respectively, and an intermediary shaft 31 and 32, respectively. The inter- mediary shafts are fixedly connected to the associated intermediary gear wheels and are rotatably mounted in a common housing 33 enclosing all the gear wheels. As dia- grammatically shown, a friction coupling is provided between the input shaft 15 and the common housing 33, said friction coupling being provided with the general reference numeral 34. Correspondingly, a friction coupling is arranged between the common housing 33 and the output shaft 22, said friction coupling being provided with the general reference numeral 35. Furthermore as diagrammatic- ally shown, a friction coupling is arranged between the common housing 33 and the frame 36 of the jigger, said friction coupling being provided with the general reference numeral 37. These couplings 34, 35 and 37 may be of any suitable type and are adapted to be individually activated. The couplings 34 and 35 are preferably activated simul¬ taneously in such a manner that either both the input shaft 15 and the output shaft 22 are coupled to the common housing 33 or the common housing 33 is coupled to the frame 36. In the first case, the common housing 33 is caused to rotate together with the input shaft 15 and the output shaft 22, whereby the rate of rotation of the input shaft 15 is transferred directly to the output shaft 22. In the latter case, the various gear wheels of the inter¬ mediary gear .17 are caused to rotate relative to one another, whereas the housing 33 is kept in position. As a result the rate of rotation of the input shaft 15 is considerably reduced so that the rate of rotation of the output shaft 22 is considerably lower than the rate of rotation of the input shaft 15 caused by the variable gear 14. The couplings 34, 35 and 36 can also be activated such that they are slowly coupled in and decoupled, whereby a slow braking of the associated main roller 1 can be ini¬ tiated. Finally, the couplings 34, 35 and 37 can be adapted to enter such a position that the main roller 1 is not caused to rotate despite the fact that the input shaft 15 is caused to rotate, which is ensured by all the couplings 34, 35 and 37 being decoupled. The second intermediary gear 18 is completely identical with the above embodiment described in connection with the intermediary gear 17. Thus the control of the couplings 34, 35 and 37 is coordinated in such a manner that the altertiate coupling of the housing to the input shaft 15 and the output shaft 22 of the intermediary gear and to the frame 36 occurs simultaneously at both intermediary gears 17 and 18. When the jigger is running, the intermediary gears 17' and 18' are arranged in the decoupled position, i.e. the coup¬ lings 34 and 35 are activated to couple the housing 33 to the input shaft 15 and the output shaft 22, while the coupling 37 is decoupled. As a result, the output speeds of the variable gear 14 are directly transferred to the main rollers 1 and 2, said speeds being adjusted by means of the variable gear in response to the registered varia¬ tions in the tension of the web of fabric 11. When the jigger is stopped upon termination of the dyeing of the web of .fabric 11, the control device 21 is adapted to automatically couple in the intermediary gears 17' and 18' by decoupling the couplings 34 and 35 and coupling in the coupling 37. When the web of fabric 11 has been re- placed by a new web and the dyeing process is being start¬ ed, the main rollers 1 and 2 are therefore automatically caused to rotate at a considerably lower speed than the one at which the output shafts 15 and 16 of the variable gear are caused " to rotate. In this manner the variable gear 14 has sufficient time for adjusting itself relative to the registered tension of the fabric without involving a piling up of web of fabric in the dye bath 3 or without involving an undesired tensioning of the web of fabric. Upon a preferably predetermined period of time the inter¬ mediary gears 17 and 18 are automatically decoupled so that the rates of rotation of the output shafts 15 and 16 of the variable gear can be directly transferred to the main rollers 1 and 2 during the continued dyeing of the web of fabric in question. The invention has been described with reference to a preferred embodiment. Many modi ications can, however, be carried out without thereby deviating from the scope of the invention. Other variable gears may for instance be used instead of the one described above. By suitably dimensioning the gear wheels of the intermediary gear, one of the two couplings present between the housing of the intermediary gear and the input or output shaft thereof can be omitted.

Claims: . . , Claims - .1. A jigjger for dyeing a web of fabric and comprising two main, rollers, where the web of fabric is alternately ounδ on and unwound from said main rollers, said jigger '5 further coriprfsing two guide rollers, about which the web of fabric is passed through a dye bath, and whereby the main rollers of the jigger are driven by driving means through a common variable gear adapted to adjust the speed of rotation of each main roller in such a manner that the 10 web βf fabric is wound thereon and unwound therefrom at a subst^,ritl-p.l * ly -constant fabric tension, c h a r a c t e r- i s e~. ' & in'that an intermediary gear (17, 18) is provided between the variable gear (14) and each of the two main * • rollets (1/ 2)^ said intermediary gear reducing in a first 15 posltftoβ tjie output speed of the variable gear (14) and in a -.Efeeond position reducing said output speed of said varirale g *r ,. (1 to a minor degree or transferring said speed , unc &nged* directly to the main rollers (1 and 2, _ . respectively) . *" 20 2. A jigger as claimed in claim 1, c h a r a c t e r¬ i s e d in that each intermediary gear (17, 18) comprises a;n input shaft (15) and an output shaft (22) arranged in mutual coaxial relationship and being fixedly connected ' to an I pufe gear wheel (23) and an output gear wheel (24), 25 respectivel , said gear wheels (23, 24) co-operating with one d-r more sets of intermediary gear wheels (25 and 26), where* each set of intermediary gear wheels comprises two intermediary gear wheels (27, 28 and 29, 39, respectively) interconnected by means of an intermediary shaft (31 and 30 ? , respectively), which is rotatably mounted in a common ho siϊkg (33), and that the housing (33) comprises two first coupling devices (34, 35) and a second coupling device (37) alternately coupling the housing (33) to the input- shaft (15, 16) and the output shaft (22) of the 35 intermediary gear (17, 18) and to the frame (36) of the jigger. 3. A jigger as claimed in claim 1 or 2, c h a r a c ¬ t e r i s e d in that the intermediary gears (17, 18) are adapted to be gradually coupled in so that they can secure a gradual braking or acceleration of the main rollers (1 and 2) . 4. A jigger as claimed in claim 1, 2 or 3, c h a r a c¬ t e r i s e d in that the intermediary gears (17, 18) are adapted to be arranged in a position where the connec- tion with the shafts of the main rollers (1, 2) is de¬ coupled.

Inventors: HENNINGSEN ERIK, JENSEN AAGE, HENNINGSEN, ERIK, JENSEN, AAGE
Applicants: HENRIKSEN VALD AS, VALD. HENRIKSEN A/S
Application year: 1990
Main classification: D06B3
IPC codes: D06B3