Combing machine

Abstract

The comber (1) comprises nippers (4) with a predetermined working speed (Vp) and a first pair (20) of separating cylinders, which have a continuous rotational movement at an angular rotational speed (WC). Control means (100) are provided for adjusting the rotational speed (WC) as a function of the working speed (Vp) of the nippers (4), so that the rotational speed (WC) increases more than proportionally as a function of the working speed (Vp).

Description

Technical Field

[0001] The object of the present invention is a comber (carding tool) for a spinning preparation line.

Background Art

[0002] In the spinning preparation line, after the initial stages of fiber opening and cleaning, carding treatment by a carding machine is envisaged, after which the fibers are provided in the form of a sliver.

[0003] After possible processing on a lap winder, when several separate slivers are joined to obtain a lap, the sliver or lap is combed by a comber (carding tool) in order to obtain a web (woven fabric) in which the fibers are highly parallel and neat.

Summary of the Invention

Problems to be Solved by the Invention

[0004] In modern machines, the basic combing operation, which is carried out at a speed of 450 - 500 strokes per minute, - intermittent supply of the lap; - with a closed nipper, the incoming fringe head is combed by a circular comber; - the fringe head is overlapped and joined to the web that has already been combed in the previous cycle, and is appropriately retracted by the separating roller during its reverse rotation; - with an open nipper, the fringe tail is combed by the straight comber of the nipper; - the fringe combed by the separating roller during its forward rotation is advanced.

[0005] Therefore, the separating roller has an alternating rotational movement. Starting from an electric motor, the separating roller control and the moving member of the separating roller that enables its alternating movement are one of the most problematic parts of the design and structure of the comber (carding tool).

[0006] These components must withstand substantial dynamic stress due to repeated stopping and restarting. As the machine speed increases, the rotational speed of the separation rollers increases proportionally in both directions. Consequently, the dynamic stress becomes increasingly severe.

[0007] These components account for at least 30% to 40% of the final cost of the combed material, making them a very significant component.

[0008] There are patent documents describing solutions for combers involving the continuous rotational motion of separation rollers; see, for example, document EP-A1-1553219.

[0009] Nevertheless, the applicant was able to confirm that the combing results were unsatisfactory in terms of the resulting web quality by experimentally reproducing the solution described in document EP-A1-1553219.

[0010] Ultimately, Coma's solution exists in which the separating roller is controlled by an electronically controlled electric motor to obtain alternating rotational motion. In this case, the complex mechanical moving parts of the separating roller are not necessary.

[0011] However, such solutions have significant drawbacks, mainly in terms of energy consumption, heating of electric motors, the lifespan of such motors, and the response of operation control.

[0012] The object of the present invention is to create a comber having a separation roller, to perform continuous rotational motion during normal combing operations, and to ensure that the combed web quality is at a satisfactory level.

[0013] Such objectives are achieved by the coma described in claim 1. Dependent claims describe further advantageous embodiments of the invention. [Brief explanation of the drawing]

[0014] The features and advantages of the shuttle according to the present invention will be provided through non-limiting examples according to the accompanying drawings and will become apparent from the specification shown below. [Figure 1] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 2] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 3] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 4] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 5] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 6] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 7] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 8] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 9] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 10] Diagrams of the shuttle according to the present invention in continuous processing steps [Figure 11] Graph for explaining the operation of the shuttle according to the present invention

Mode for Carrying Out the Invention

[0015] The shuttle according to the present invention includes a fixed frame and a nipper 4 supported by the fixed frame.

[0016] The nipper 4 includes a lower jaw 6, an upper jaw 8, and a straight shuttle 10 that is usually attached to the lower jaw 6.

[0017] Also, the nipper 4 can be intermittently rotated by a command and includes a feed roller 12 supported by the lower jaw 6.

[0018] The comber further includes a first pair of separating rollers 20 including an upper separating roller 20a and a lower separating roller 20b downstream of the nipper 4, and generally presses against the upper separating roller 20a, thereby pulling it into rotation.

[0019] Between the separating rollers 20a, 20b, on the side of the nipper 4, there is an inlet port 22 for carrying a section (portion) of the sliver released by the nipper 4 by the feed roller 12. On the other side, there is an outlet port 24.

[0020] The comber further includes a second pair of separating rollers 30 downstream of the first pair 20, and the second pair 30 includes an upper separating roller 30a and a lower separating roller 30b, and generally presses against the upper separating roller 20a, thereby pulling it into rotation.

[0021] Between the separating rollers 30a, 30b, on the side of the nipper 4, there is an inlet port 32, and on the opposite side, there is an outlet port 34.

[0022] Also, preferably, the comber includes a fixed table 36 disposed between the first separating rollers 20a, 20b and the second separating rollers 30a, 30b. Preferably, the table 36 has a bearing surface 38, is generally flat, and is disposed between the ports of the first separating rollers 20a, 20b and the ports of the second separating rollers 30a, 30b.

[0023] The comber further includes a circular comb 40 generally disposed below the nipper 4 and having a continuous rotational movement at a constant or variable speed in always the same direction.

[0024] The comber includes one or more electric motors and a plurality of transmission members suitable for transmitting the operation from at least one electric motor to the aforementioned components.

[0025] In particular, the nipper has a forward and backward movement, and the jaw has an opening and closing movement at a predetermined working speed Vp.

[0026] In particular, the nipper 4 has jaws 6 and 8 that alternately move forward and backward between a forward limit position proximal to the separation rollers 20a and 20b and a backward limit position distal to the separation rollers 20a and 20b.

[0027] Simultaneously, jaws 6 and 8 have alternating opening and closing movements, while feed roller 12 has an intermittent rotational movement that allows for the release of a portion (section) of the sliver from the nippers.

[0028] The first pair of separation rollers 20a and 20b have a continuous rotational motion (at a constant or variable speed, but without reversing), and each has an angular rotational speed Wc in one direction of rotation to separate the fiber fringe from the sliver portion at the inlet port 22.

[0029] Similarly, the separating rollers 30a and 30b of the second pair 30 have a continuous rotational motion synchronized with that of the cylinders 20a and 20b of the first pair 20.

[0030] The comber further comprises a support section 50 downstream of the second pair 30 of separation rollers 30a, 30b, which receives the fringes of sliver continuously supplied from the separation rollers 30a, 30b of the second pair 30.

[0031] Preferably, the support portion 50 is permeable to air and is operably connected to a suction device to obtain a surface-passing suction airflow suitable for holding the fringe.

[0032] Furthermore, the support portion 50 is movable and, by moving forward, allows for partial overlap of the fringes that are continuously present above it.

[0033] For example, the support section 50 is a breathable belt arranged along the closed circuit.

[0034] Along the support portion of the closed circuit, the belt 50 runs on a rigid base 52 connected to the suction duct 54 of the suction device.

[0035] Furthermore, preferably, along the closed path, the belt 50 cooperates with the belt rollers 56, 58 and the pair of tension rollers 60 that define the closed path.

[0036] For example, the pair 60 of tension rollers preferably comprises an upper tension roller 60a on the outside of the closed circuit and a lower tension roller 60b on the inside of the closed circuit.

[0037] The belt 50 is compressed between tension rollers 60a and 60b to obtain forward motion, with at least one of them being electrically operated and the other being non-operating (idle).

[0038] Preferably, the comber further comprises a pair of compression rollers 70 suitable for compressing the web formed by the overlap of fringes on the belt 50.

[0039] In particular, the pair of compression rollers 70 comprises an upper compression roller 70a and a lower compression roller 70b that are pressure-coupled.

[0040] Preferably, the compression rollers 70a and 70b also function as tension rollers 60a and 60b.

[0041] Furthermore, preferably, the comber includes a pair of output rollers 80 located downstream of the compression rollers 70a, 70b. For example, the pair of output rollers 80 comprises an upper output roller 80a and a lower output roller 80b, which are pressure-coupled, with at least one being electrically powered and the other being non-operating (idle).

[0042] To illustrate the comb's operation, it is initially recognized that the nippers 4 are at their forward limit position and the jaws 6 and 8 are open (Figure 1). The feed roller 12 is stopped, and the first fringe U1 is separated by the separation rollers 20a and 20b, which have a continuous rotational motion in the direction of pulling out from the nippers. While the first fringe U1 is moving forward, the outgoing tail is combed by the straight comb 10.

[0043] Next, the nippers 4 begin to retract, the straight comb 10 finishes combing the first fringe U1, and the continuous rotation of the separation rollers 20a and 20b transports it toward the belt 50 or toward the second separation rollers 30a and 30b (Figure 2). The feed roller 12 rotates to bring in new pieces of sliver from the lower jaws 6.

[0044] Next, the nippers 4 continue to retract, and as with the rotation of the feed roller 12, this removes even more sliver from the lower jaws 6. The continuous rotation of the separation rollers 20a and 20b advances the first fringe U1 (Figure 3).

[0045] Next, the nippers 4 reach their closed limit retracted position as the lower jaws 6 and upper jaws 8 engage with each other (Figure 4). The circular comb 40, which performs a continuous rotational motion, is at an angular position to begin combing the head of the second fringe U2. The feed roller 12 stops again, and the first fringe U1 continues to move forward due to the continuous rotation of the separation rollers 20a and 20b.

[0046] Next, while the nippers 4 remain stationary, the circular comb 40 continues combing the head of the second fringe U2 (Figures 5, 6, and 7). The first fringe U1 continues to advance due to the continuous rotation of the separating rollers 20a and 20b.

[0047] Next, the nipper 4 resumes its forward movement, and the circular comb 40 finishes combing the head of the second fringe U2 which is provided to the separation rollers 20a, 20b (Figure 8). Meanwhile, the first fringe U1 is passed to the second separation rollers 30a, 30b, and the fringe U0 in front of the first fringe U1 leaves the second separation rollers 30a, 30b and is carried onto the belt 50, where it rests.

[0048] Next, the nipper 4 continues to advance toward its limit forward position, and the second fringe U2 engages with the first separation rollers 20a and 20b. Meanwhile, the first fringe U1 advances due to the action of the second separation rollers 30a and 30b.

[0049] Finally, when the nipper 4 reaches its forward limit position (Figure 10), the new fringe is separated from the sliver by the first separation rollers 20a, 20b at the inlet port 22.

[0050] As a result of the sequence of the above steps, the first fringe U1 leaves the second separation rollers 30a and 30b, and the front fringe U0 moves forward due to the movement of the belt 50, so that its head is carried onto the belt 50 so that it overlaps with the tail of the front fringe U0.

[0051] In this way, a continuous web is formed on the belt 50, where the head of the following fringe overlaps with the tail of the previous fringe.

[0052] The web thus formed passes between the compression rollers 70a and 70b to adjust its thickness.

[0053] According to the present invention, the comber includes a control means 100 suitable for adjusting the rotational speed Wc of at least one of the separating rollers 20a, 20b as a function of the working speed Vp of the nippers 4. The control means 100 is configured or programmed such that the rotational speed Wc as a function of the working speed Vp of the nippers 4 follows a predetermined rule.

[0054] In other words, the control means 100 is suitable for adjusting the rotational speed (generally in rpm) of the separating rollers 20a and 20b as a function of the machine's working speed, that is, as a function of the number of strokes or cycles per unit of time (generally, strokes / minute) of the nippers.

[0055] The control means 100 is configured or programmed to follow a predetermined law such that the rotational speeds of the separation rollers 20a and 20b are not linearly proportional as a function of the machine's operating speed.

[0056] In the graph in Figure 11, the horizontal axis represents the working speed Vp of the nippers, expressed as strokes / minute, and the vertical axis represents the ratio R between the rotational speed Wc (rpm) of the separating roller and the working speed Vp of the nippers.

[0057] The dashed line T shows the trend of such a ratio R for a conventional machine. This trend T is parallel to the horizontal axis because, as the working speed of the conventional comber increases, the rotational speed of the separation rollers increases proportionally and linearly. As a result, the ratio remains constant (equal to 3 in the example graph in Figure 11).

[0058] The continuous line C, according to one embodiment, shows the trend of the coma ratio according to the present invention. The trend of the ratio is increasing, and can be approximated by a partially linear function as the machine's working speed Vp increases, for example, until the machine's working speed Vp reaches a value between 2 and 2.5, for example, until it reaches a value equal to 2.25.

[0059] For example, according to the graph in Figure 11, at the initial working speed Vp0, i.e., 100 strokes / min, the rotational speed Wc0 of the separation roller is equal to, for example, about 50 rpm. At the intermediate working speed Vp1 (Vp1 > Vp0), for example, equal to 500 strokes / min, Wc1 is equal to, for example, about 750 rpm. The trend of the ratio R = Wc / Vp between Vp0 and Vp1 is approximated by an increasing linear function having a first predetermined slope S1.

[0060] At the limiting working speed Vpf (Vpf>Vp1>Vp0), for example, 700 strokes / min, Wcf is, for example, approximately 1680 rpm. Between Vp1 and Vpf, the trend of the ratio R=Wc / Vp is approximated by an increasing linear function having a second predetermined slope S2 (S2>S1) greater than the first slope S1.

[0061] Therefore, the trend of the rotational speed Wc of the separation roller has an increasing trend that is not proportional with respect to the working speed Vp (e.g., R = Wc / Vp, or partially linear or nonlinear).

[0062] In other words, according to the present invention, as the working speed Vp of the machine increases, the rotational speed Wc of the separation roller increases more than proportionally, according to a predetermined law.

[0063] The applicant has found that by increasing the rotational speed of the separation rollers more than proportionally, and especially more than linearly, the quality of the resulting webs is significantly improved as the machine's working speed increases.

[0064] At the same time, the applicant found that, while maintaining a proportional relationship between the machine's working speed and the rotational speed of the separation roller, the web quality was insufficient, as in the case of prior art combers, and sometimes the fringe tended to wrap around the same separation roller.

[0065] The control means 100 operates while the comber is operating at full speed, imposing a desired rotational speed Wc on the separation rollers 20a and 20b, and during the transition phase necessary to increase the comber to working speed Vp, for example, starting from a stationary machine state.

[0066] During the transition phase, the control means 100 operates in such a way that, as the working speed Vp of the comber increases, it imposes on the separation rollers 20a and 20b a rotational speed Wc that is a function of the working speed Vp, but increases more than proportionally.

[0067] Innovatively, the coma according to the present invention overcomes the shortcomings mentioned with reference to the prior art.

[0068] In particular, a significant advantage is that, according to the present invention, the comb is extremely compact because it does not require the complex components necessary for the alternating motion of the separation rollers in the prior art.

[0069] Furthermore, an advantage is that there are no components that are subjected to large dynamic stresses, such as the control members of conventional separation rollers.

[0070] It is clear that a person skilled in the art may make further modifications to the above coma to satisfy incidental needs, all of which fall within the scope of protection as defined by the following claims.

Claims

1. A comber (1) for a spinning preparation line, suitable for processing fiber slivers to obtain a web, is: Nippers (4) including a lower jaw (6), an upper jaw (8), and a feed roller (12) supported by the lower jaw (6), A first pair (20) of separation rollers located downstream of the nipper (4), A control means (100) for adjusting the rotational speed (Wc), which is expressed as the number of rotations per minute of at least one of the separating rollers (20a, 20b), as a function of the working speed (Vp), which is expressed as the number of strokes per minute of the nipper (4), A straight comb, Equipped with, 1) The nippers have forward and backward movement, and simultaneously, the jaws have opening and closing movement at a predetermined working speed (Vp), The nippers have jaws 6 and 8 that alternately move forward and backward between a forward limit position proximal to the separation rollers 20a and 20b and a backward limit position distal to the separation rollers 20a and 20b, When nipper 4 is in its forward limit position, jaws 6 and 8 are recognized as being open. When the nippers 4 reach their closed, fully retracted position, the lower jaw 6 and the upper jaw 8 engage with each other. 2) The feed roller (12) has an intermittent rotational motion, The feed roller stops when the nipper is at its forward limit position and when it is at its reverse limit position, and the feed roller rotates simultaneously as the nipper moves from the forward limit position to the reverse limit position, allowing a portion of the sliver to be released from the nipper. The first pair comprises an upper separation roller (20a) and a lower separation roller (20b), with an inlet port (22) defined on the nipper side between them for the nipper (4) to carry a portion of the sliver, and an outlet port (24) defined on the other side. The separation rollers (20a, 20b) have a continuous rotational motion at a rotational speed (Wc) in the rotational direction for separating the fiber fringe (U1) from the sliver portion of the inlet port (22), and when the nipper reaches its forward limit position, it advances the fiber fringe (U1) toward the outlet port (24), while the nipper (4) moves toward its retraction limit position. When the nipper (4) reaches its forward limit position, the straight comb combs the advancing fiber fringe (U1). The control means (100) is configured or programmed to increase the rotational speed (Wc) more than proportionally as a function of the working speed (Vp) of the nippers (4). The control means (100) is configured or programmed such that the rotational speed (Wc) tends to increase more than when the ratio R = Wc / Vp as a function of the working speed (Vp) of the nipper (4) is proportional.

2. A comber according to claim 1, comprising a movable support (50) located downstream of a first pair (20) of separation rollers (20a, 20b) and receiving fringes of sliver continuously supplied from the separation rollers (20a, 20b).

3. The comber according to claim 2, wherein the support portion (50) is air permeable, operably connected to a suction device to obtain an airflow for suction passing over the upper surface, and configured to hold the fringe.

4. The comba according to claim 2 or 3, wherein the support portion (50) is configured to move forward so as to allow for partial overlap of a later fringe (U1) that is continuously present on a previously received fringe (U0) above it.

5. The support portion (50) is a belt arranged along the closed circuit, the comb according to any one of claims 2 to 4.

6. A comber according to claim 5, comprising a pair (60) pressure-coupled, the pair including a first tension roller (60a) outside the closed loop and a second tension roller (60b) inside the closed loop, between which a belt is pulled for forward movement.

7. A comber according to any one of claims 1 to 6, comprising a second pair of separation rollers (30) located downstream of a first pair (20), including an upper separation roller (30a) and a lower separation roller (30b), which receive the sliver fringes formed by the first pair (20).

8. Located downstream of the first pair (20) of separation rollers (20a, 20b), it includes a movable support (50) that receives the sliver fringe continuously supplied from the separation rollers (20a, 20b), The comber according to claim 7, wherein the support portion (50) is located downstream of the second pair (30) of the separation rollers (30a, 30b).

9. A comber according to claim 7 or 8, comprising a fixed table (36) positioned between a first pair (20) of separating rollers (20a, 20b) and a second pair (30) of separating rollers (30a, 30b), wherein the fixed table (36) has a bearing surface (38) positioned between the outlet port (24) of the first separating rollers (20a, 20b) and the inlet port (32) of the second separating rollers (30a, 30b).

10. A comber according to any one of claims 3 to 9, as dependent on claim 3, comprising a pair of compression rollers (70) positioned downstream of a support (50) for compressing a web formed by overlapping fringes on the support (50) to obtain a certain thickness.

11. To provide a comb according to any one of claims 1 to 10, To increase the working speed (Vp) of the nippers until it reaches the maximum operating speed (Vpf), To increase the rotational speed (Wc) of at least one of the separating rollers (20a, 20b) of the first pair (20) by a greater amount than the case where it is proportional as a function of the working speed (Vp) of the nippers, A method for working with combed cotton, which includes the following features.

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