WO2014016769A1

WO2014016769A1 - Method for adjusting the advancement of a fiber web to the detaching cylinders of a combing machine and kit therefor

Info

Publication number: WO2014016769A1
Application number: PCT/IB2013/056034
Authority: WO
Inventors: Girolamo Prandini; Luca SOLIANI
Original assignee: Marzoli S.P.A.
Priority date: 2012-07-27
Filing date: 2013-07-23
Publication date: 2014-01-30
Also published as: CN104520479B; BR112015000720B1; CH708536B1; CN104520479A; DE112013003704T5; ITBS20120123A1; JP6333247B2; IN2015DN00479A; JP2015526606A; DE112013003704B4; BR112015000720A2

Abstract

A method for adjusting the advancement of a fibre web performed by the feed cylinder (12), fitted on the nipper (4) of a combing machine provides for replacing the main wheel (14') attached to the feed cylinder (12) with a further wheel having a different number of teeth and the same pitch as the former, without modifying the configuration of the nipper.

Description

DESCRIPTION

"METHOD FOR ADJUSTING THE ADVANCEMENT OF A FIBRE WEB TO THE DETACHING CYLINDERS OF A COMBING MACHINE AND KIT

THEREFOR" .

[0001] The present invention relates to a method for adjusting, in a combing machine, the advancement of a fibre web to the detaching cylinders of the combing machine .

[0002] On a yarn preparation line, after the initial phases of opening and cleaning the fibre, carding is performed by carding machines, after which the fibre appears in the form of a web.

[0003] After processing, if any, on a lap-winder, in which various separate webs are combined to form a lap, the web or lap is combed by a combing machine, so as to obtain a web in which the fibres are highly parallel and clean.

[0004] The combing machine comprises a nipper group, comprising a lower jaw, an upper jaw and a feed cylinder, supported by a lower frame, and at least a pair of detaching cylinders, downstream of the nipper group.

[0005] The web entering the combing machine is taken to the feed cylinder, which has an intermittent movement and, keeping the web pinched, makes just a tuft emerge;^' the tuft, combed at the head by the circular comb, is detached by the detaching cylinders, so as to be combed at the tail by the rectilinear comb and joined to the previous tuft.

[0006] The length of the tuft fed by the feed cylinder is particularly important for the quality of the web; in general, the shorter the tuft the better the quality; however the shorter the length of the tuft is, the lower plant productivity.

[0007] According to the type of fibre being processed and the desired quality of the web, adjustment operations of the nipper group are required to vary the entity of the intermittent rotation of the feed cylinder and thereby the length of the tuft.

[0008] The need to perform such adjustment operations must be borne in mind during the design of the combing machine. Such requirement makes the design, and in particular the definition of the laws of motion governing the alternate movement of the jaws, particularly complex.

[0009] In addition, such adjustment operations entail long machine downtime and testing procedures before resuming operation, with consequent productivity loss of the plant .

[0010] The purpose of the present invention is to provide an adjustment method of the intermittent movement of the feed cylinder of a combing machine which satisfies the aforesaid requirements and overcomes the drawbacks mentioned with reference to the prior art.

[0011] Such purpose is achieved by an adjustment method performed according to claim 1_*

[0012] The characteristics and advantages of the adjustment method according to the present invention will be evident from the description below, made by way of a non-limiting example, with reference to the appended drawings, wherein :

[0013] - figure 1 shows a nipper group of a combing machine, suitable for performing the adjustment method according to the present invention;

[0014] - figure 2 shows a schematic side view of the nipper group in figure 1; and

[0015] - figures 3a, 3b and 3c show the nipper group of figure 1 respectively provided with a different main wheel.

[0016] A combing machine according to the invention comprises a nipper group 1 and a circular comb suitable for being operated in rotation, positioned under the nipper group.

[0017] The nipper group 1 comprises a nipper 4. The nipper 4 comprises lower jaw 6, supported by a lower frame 7, an upper jaw 8, supported by an upper frame 9 and hinged on a hinge axis 10 to the lower jaw 6, and a rectilinear comb, integral with the lower jaw, in the front area thereof .

[0018] In addition, the nipper group 1 comprises a feed cylinder 12, rotating on command, supported by the lower jaw 7. The feed cylinder 12 is consequently positioned on the nipper 4.

[0019] Downstream of the nipper group 1, pairs of detaching rollers are provided, rotating on command with alternate rotatory movement.

[0020] The nipper 4 has an alternate back and forth movement; in a forward position, the jaws 6, 8 are proximal to the detaching rollers and open, so as to permit the combing of the tail of the tuft by the rectilinear comb; in a rearward position of the nipper, the jaws 6, 8 are distal from the detaching rollers and pinched closed, so as to permit the combing of the head by the circular comb.

[0021] During the advancement step of the nipper, that is when the nipper moves from the rearward position to the forward position, or during the return step, that is when the nipper moves from the forward position to the rearward position, the feed cylinder performs an intermittent rotation, according to a direction of advancement A, so as to advance a section of the web, to form a new tuft to be combed.

[0022] To such purpose, the nipper group comprises a main wheel 14, joined in rotation to the feed cylinder 12; for example, the main wheel 14 is attached, in a removable manner, to the axial end of the feed cylinder 12, coaxially thereto.

[0023] The main wheel 14 is provided with a plurality of teeth 16, in circumferential sequence, between which hollows 18 are made.

[0024] The nipper group 1 further comprise intermittent drive means of the main wheel 14, synchronised with the nipper 4.

[0025] For example, the intermittent drive means comprise a lever 20, hinged to the upper frame 9, suitable for engaging with the main wheel 14 to force it in rotation in the direction of advancement A.

[0026] Preferably, the lever 20 comprises a termination 22 suitable for being inserted in the hollows 18 between the teeth 16 of the main wheel 14.

[0027] The lever 20 is rotatable in a synchronised manner with the nipper 4, so that the rotation of the lever 20 takes place when the lower jaw 6 is in a predefined position in relation to the detaching cylinders.

[0028] A pitch "p" and a number of teeth "Z" are defined for the main wheel 14 having a characteristic diameter "D". The diameter D, pitch p and the number of teeth Z are related by the formula p*Z = n*D. [0029] At each combing cycle, the lever imposes a controlled rotation on the wheel 20 corresponding to a pitch; in other words the termination 22 of the lever disengages from a hollow 18 and goes to engage the adjacent hollow.

[0030] Let us assume that the nipper group 1 is provided with a main wheel 14' having a diameter Dl, a number of teeth Zl and a pitch pi.

[0031] At each stroke of the combing machine, the feed cylinder will undergo a rotation, to which a predetermined advancement of the web corresponds.

[0032] In order to achieve a variation of the advancement of the web, the adjustment method provides for replacing the first main wheel 14' with a second main wheel 14" having a pitch p2 substantially equal to the pitch pi of the first main wheel 14', a number of teeth Z2 different from the number of teeth Zl of the first main wheel 14' and a diameter D2 different from the diameter Dl of the first main wheel 14¹. .

[0033] Following such replacement, the second main wheel 14" finds itself already placed in the angular position permitting engagement with the intermittent drive means, that is with the termination 22 of the lever 20, which may be inserted in the hollows between two teeth of the second main wheel 14". [0034] The pitch p2 of the second main wheel 14" is "substantially" equal to the pitch pi of the first main wheel 14' in the sense that slight differences between the two pitches are possible, so as to make up for any clearance or dimensional variations.

[0035] In any case, according to the adjustment method, after replacing the first wheel 14' with the second wheel 14", the step of engaging the means of advancement with the second wheel 14"' without modifying the configuration of the nipper, that is without modifying the reciprocal distance between the jaws, follows.

[0036] The adjustment method provides for use of a kit of main wheels having substantially the same pitch p, but different numbers of teeth Z and therefore different diameters D.

[0037] In addition, when one main wheel needs to be replaced by another having a different number of teeth, the adjustment method permits such replacement in any configuration of the nipper; in other words, conversely to as happens with the combing machines of the prior art, the nipper groups does not need to be placed in a specific adjustment configuration defined by a diameter.

[0038] Preferably, instead, the adjustment method according to the invention provides for bringing the nipper into a ' predefined adjustment configuration, in which the lower jaw 6 and the upper jaw 8 are placed in a predefined reciprocal position, only for the first adjustment, that is for the adjustment performed by specialised technicians to assemble the combing machine in the spinning line.

[0039] Innovatively, the adjustment method according to the present invention satisfies the requirements and overcomes the drawbacks mentioned with reference to the prior art .

[0040] Advantageously, in fact, the adjustment method makes it possible to rapidly adjust the advancement of the web, by replacing one main wheel with another, without modifying the reciprocal position between the jaws of the nipper in the configuration adopted during the adjustment.

[0041] According to a further advantageous aspect, the adjustment method permits simplification of the design phase, and in particular permits optimal definition of the laws of motion of the jaws, in that the relative positioning between the jaws is not modified during the adjustment .

[0042] It is clear that a person skilled in the art may make modifications to the method described above so as to satisfy contingent requirements while remaining within the sphere of protection of the following claims.

Claims

1. Adjustment method, in a combing machine on a yarn spinning line, of the intermittent advancement of a fibre web performed by a feed cylinder (12) positioned on a nipper (4) and movable by means of advancement, comprising, in one configuration of the nipper, the step of replacing a first main wheel (14') attached to the feed cylinder (12), having a first diameter (Dl) , a first number of teeth (Zl) and a first pitch (pi), with a second main wheel (14' ') having a second pitch (p2) substantially equal to the first pitch (pi) and a second diameter (D2) different from the first diameter (Dl) of the first wheel (14' ), and the step of engaging the means of advancement with the second wheel (14' ') without modifying the configuration of the nipper.

2. Kit for performing an adjustment method, in a combing machine on a yarn spinning line, of the intermittent advancement of a fibre web performed by a feed cylinder (12) positioned on a nipper (4), comprising a plurality of main wheels (14' , 14" , 14' " ) having a substantially equal pitch (pl,p2,p3), different diameters (D1,D2,D3) and different numbers of teeth (Z1,Z2,Z3.