Improvements in or relating to machines for treating fabrics in open width

Abstract

 In a machine for treating (scouring and/or fulling) fabrics in open width, provided with a tank with which there are associated means for widening the fabric (A) originating from the bottom of the tank (1), fabric centering means (10) positioned downstream of the preceding means, fabric transporting means (28) and means (Z) for launching the fabric against a counteracting surface (29) before falling onto the bottom of the tank.
The means (Z) for launching it against the counteracting surface (29) comprise a fabric detachment system which includes driven endless belts.

Description

[0001] This invention relates to a machine for treating (scouring and/or fulling) fabrics particularly of vegetable or synthetic fibres in open width, of the type provided in succession with at least one tank, means for widening the fabric rising from the tank, means for transporting the widened fabric and a counteracting surface positioned within the path of movement of the fabric so that the fabric strikes against it.

[0002] Known machines of this type have the drawback that if the fabric is not conveniently centered about the fabric transporting means, it suffers substantial and permanent damage, such as irreparable beating or even tearing, and in addition the fabric, especially if wet, tends to wind about the transporting means.

[0003] It is already known to use so-called centering devices, however for their operation, in the sense of detecting off-centering and correcting it on the basis of the detected error, they use members which press on the fabric above the idle deviation roller about which the fabric passes. The action of these members is controlled by a sensor, and as it is intermittent it causes the fabric to undergo possibly unremovable creasing when operating at the high speeds necessary for current production requirements.

[0004] The main object of the present invention is therefore to centre the fabric after its widening such that the aforesaid drawbacks do not occur even when operating at high speed and to prevent the fabric adhering to the transporting means by wrapping around them.

[0005] A further object is to provide effective centering means of lesser technical and constructional complication and hence of acceptable cost.

[0006] These and further objects which will be more apparent from the detailed description given hereinafter are attained by a machine of the aforesaid type but improved in accordance with the teachings contained in the accompanying claims.

[0007] The invention will be more apparent from the detailed description of some embodiments thereof given hereinafter by way of non-limiting example and illustrated on the accompanying drawings, in which:

Figure 1 is a schematic longitudinal vertical section through a first embodiment of the machine of the invention;

Figure 2 is a perspective view of the centering means which are incorporated in all the embodiments represented and described herein;

Figure 3 is a schematic side elevation showing the centering means of Figure 1 associated with fabric off-centre sensing means;

Figure 4 is a perspective view of a different embodiment, the view being limited to those parts of the machine relevant to the invention;

Figure 5 is a view analogous to that of Figure 1 showing a further embodiment of the invention;

Figure 6 is a schematic side view of a further embodiment of the machine, the view being limited to that which concerns the invention;

Figure 7 is a side view of an important detail which can be common to at least some of the embodiments shown in the preceding figures.

[0008] With reference to Figures 1 to 3 and Figure 7, the machine for wet-treating fabrics in open width, discontinuously in this case, comprises a usual metal tank 1.

[0009] The ends of the fabric to be treated, indicated by T, are sewn together in the usual manner so that the fabric forms a ring. The direction of movement of the fabric is indicated by the arrows A and B.

[0010] During its ascending movement (arrow A) the fabric passes through a conventional widener 2. It comprises two identical rollers 3, 4 driven by an electric motor, not shown, and supported for example by the sides of the tank. One of the rollers is visible in the detailed view of Figure 2, in which it can be seen that, starting from its centre line Z1, it possesses two helical projections, one right-handed and the other left-handed, indicated respectively by 4* and 5. The two rollers are supported on the sides of the tank by means of two arms 7 and two pins 8, one arm and one pin being positioned at each of the two ends of the rollers 3, 4. A helical gear 9 is keyed onto a pin emerging from the tank and engages a worm, not shown, operated by a handwheel, also not shown, in order, inter alia, to enable said rollers to be correctly positioned relative to the fabric T, the position being correct if the fabric adheres to the two rollers. After passing through the widening device 2, where the fabric is widened by the action of the opposing helical projections 4*, 5 on the rollers, the fabric passes to a centering device 10.

[0011] This centering device comprises at least one idle roller 11 covered with elastic material, eg rubber, able to exert a certain friction on the fabric T.

[0012] This roller is projectingly supported between two end plates 12 connected together by a cross-member 13.

[0013] The cross-member is supported at each end by pairs of plates 14 via a hinge pin 15. Each pair of plates is supported lowerly by a pin 16, which is rigid with a fixed cross-member 17. The assembly formed by the cross-members 13, 17, the plates 14 and the pins 15 and 16 forms an articulated parallelogram which is moved by a double-acting pneumatic cylinder 18 hinged to a support 19 rigid with the cross-member 17 and whose rod 20 is hinged at 21 to the upper cross-member 13.

[0014] The fabric T passes from the idle roller 11 to a fabric centering detection station 22. This station comprises an arrangement of means, photoemitters and photoreceivers, for example light emitting diodes (LEDs), photodiodes, photoelectric cells and the like, positioned to correspond with the longitudinal edges of the fabric when ideally centered and extending transversely.

[0015] It is apparent that if the fabric is off-centre, the photoreceivers on the off-centered side will be obscured.

[0016] A signal is hence produced which when suitably amplified causes valve means to operate in order to drive the double-acting pneumatic cylinder 18 in the direction to zero the off-centering.

[0017] Returning now to Figure 1, after passing the two deviation rollers 23 the fabric T reaches a motorized endless band 28 where it is subjected to the pressing action of an idle roller 24 supported by arms 25, which are hinged at 26 and are acted upon by a pneumatic cylinder 27 which adjusts the pressure exerted on the fabric.

[0018] The band 28, which moves at relatively high speed, conveys the widened and centered fabric to a device Z which launches the fabric against a counteracting surface 29 of adjustable position, to then fall onto the bottom of the tank and recommence the described operating cycle.

[0019] The device 7 is shown in Figure 7 and is described in detail hereinafter with reference to that figure.

[0020] The embodiment of Figure 4 shows very schematically both the widening device 2A and the centering device 10A, which coincide with those shown in the preceding figures. Downstream thereof, the fabric T encounters a pair of cooperating grooved rollers 40, one idle and the other driven, which are pressed against each other. The arched teeth 41 of two comb structures 42 extend into the relative grooves, the teeth of the lower structure being the longer and accompanying the fabric towards a motorised device 43, in synchronism with the preceding, and consisting of three grooved rollers 44, 45, 46, belts 47 moving within their grooves. A grooved idle fourth roller 48 presses on the underlying roller 44 under the thrust of a pneumatic cylinder, not shown, within its grooves there extending endless belts 90 which pass within the grooves of a further preferably driven roller 91.

[0021] As will be more apparent from the description of Figure 7, the roller 91 corresponds basically to the roller 70 (of Figure 7), and the belts 90 to the belts 47D, and in the embodiment of Figure 4 fixed detachment bars 71 are provided, although not shown, interposed between the belts.

[0022] To prevent the belts dragging the fabric with them beyond the roller 44, detachment or separation bars 49 are interposed comb-like between the belts and are fixed at their ends to cross-members 50. The bars 49 are arched and project beyond the plane containing the belt portions extending between the rollers 44, 45.

[0023] As can be seen from Figure 4, a modified embodiment is possible in which the roller 46 is omitted, so that the belts pass from the roller 45 to the roller 44 (see line R), this device being positioned close to the exit of the lower comb 41 to be able to adequately receive the fabric. Alternatively, this comb can be lengthened. Basically this modification coincides with the device Z of Figure 7.

[0024] The embodiment shown in Figure 5 comprises a tank 1B receiving the fabric T, the widening device 2B and the centering device 10B with its sensors 22B. The fabric leaving the sensors 22B passes about an idle deviation roller 50* to enter a bath 51, then passes between two presser rollers 70, one idle and the other driven, these being provided to exert a pressure on the passing fabric so as to drag it. The fabric then reaches a device Z of Figure 7 and from here is launched against an adjustable counteracting surface 29B before falling into the tank.

[0025] The arrangement is indicated by the preceding reference numerals accompanied by the letter B.

[0026] The embodiment of Figure 6 comprises the widening device 2C, the centering device 10C with its sensors, and reversal rollers 60, the fabric T passing between two rollers, a lower large-diameter one 61 and a smaller diameter one 62. The former is motorized while the latter is idle and exerts on the former a pressure, for example by means of a pneumatic cylinder. The fabric then passes through the device Z of Figure 7, the components of which are consequently indicated by the same reference numerals followed or not followed by a letter.

[0027] Before falling onto the tank bottom, the fabric, not shown, strikes against an adjustable counteracting surface 29C similar to that of Figure 1 or to 29B of Figure 5.

[0028] Figure 7 shows the device Z (associated with the band 28 of Figure 1), comprising the grooved roller 48A, 48B cooperating with belts 47D passing about a further grooved roller 70 cooperating with interposed detachment bars 71 similar to the bars 49 (of Figure 4).

[0029] The roller 48A, 48B cooperates with the grooved roller 44A, 44B, the grooves of which receive the belts 47 between which the fabric detachment bars 49 extend.

[0030] The following modifications fall within the scope of the invention:

a) the use of 2 or 3 idle rollers instead of the single roller 11 of the centering device 10 (these rollers being mounted spaced apart but mutually parallel on the rocking structure which controls the centering roller 11);

b) the off-centre sensors, ie the members 22, can instead be mounted upstream of the roller or rollers 11 of the centering device 10, ie between the widener 2 and roller 10, or can be provided both upstream and downstream of the roller or rollers 11.

Claims

1. A machine for discontinuously treating (scouring and/or fulling) fabrics particularly of vegetable or synthetic fibres in open width, comprising a tank, means associated therewith for advancing the fabric and means for widening and centering it, characterised in that the centering means comprise means for detecting off-centering of the fabric, to control a double-acting pneumatic piston which transversely shifts at least one idle roller or a two or three-roller system depending on the off-centering, there being provided driven exit means for the fabric to launch the fabric against a counteracting surface and including members to prevent the fabric winding about or adhering to them.

2. A machine as claimed in claim 1, characterised in that downstream of the centering device there is provided a driven endless band on which there presses at least one idle rolling member controlled by pneumatic means, the fabric exit means being provided downstream of the band.

3. A machine as claimed in claim 2, characterised in that the exit means are positioned between the band and counteracting surface and comprise at least two grooved rollers with endless belts passing within the grooves, into the spaces between the belts there projecting bars for detaching any fabric adhering to the belts.

4. A machine as claimed in claim 3, characterised by comprising at least two pairs of two grooved rollers with relative belts and detachment bars interposed between the belts.

5. A machine as claimed in claim 1, characterised in that downstream of the centering device there is provided a first pair of cooperating grooved rollers, into the relative grooves there extending fixed or adjustable arched teeth or fingers.

6. A machine as claimed in claim 5, characterised in that downstream of the first pair of grooved rollers there are provided grooved rollers carrying endless belts within their grooves, arched bars for fabric detachment being positioned between these belts.

7. A machine as claimed in claim 1, characterised in that downstream of the centering device there are provided a bath, pressing rollers and then an arrangement comprising at least one pair of grooved rollers with belts and arched bars for fabric detachment, and a counteracting surface against which the fabric strikes.

8. A machine as claimed in claim 1, characterised in that downstream of the centering device there is provided a pair of cooperating rollers of substantially different diameters, downstream of these there being provided an arrangement comprising at least one pair of grooved rollers carrying endless belts within their grooves and with intermediate arched bars for fabric detachment, downstream of this arrangement there being provided a counteracting surface.

Drawing