Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01H—SPINNING OR TWISTING
  • D01H1/00—Spinning or twisting machines in which the product is wound-up continuously
  • D01H1/14—Details
  • D01H1/20—Driving or stopping arrangements
  • D01H1/22—Driving or stopping arrangements for rollers of drafting machines; Roller speed control
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01H—SPINNING OR TWISTING
  • D01H1/00—Spinning or twisting machines in which the product is wound-up continuously
  • D01H1/02—Spinning or twisting machines in which the product is wound-up continuously ring type
  • D01H1/025—Spinning or twisting machines in which the product is wound-up continuously ring type with a condensing device between drafting system and spinning unit
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01H—SPINNING OR TWISTING
  • D01H5/00—Drafting machines or arrangements ; Threading of roving into drafting machine
  • D01H5/18—Drafting machines or arrangements without fallers or like pinned bars
  • D01H5/26—Drafting machines or arrangements without fallers or like pinned bars in which fibres are controlled by one or more endless aprons
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01H—SPINNING OR TWISTING
  • D01H5/00—Drafting machines or arrangements ; Threading of roving into drafting machine
  • D01H5/18—Drafting machines or arrangements without fallers or like pinned bars
  • D01H5/70—Constructional features of drafting elements
  • D01H5/72—Fibre-condensing guides
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01H—SPINNING OR TWISTING
  • D01H5/00—Drafting machines or arrangements ; Threading of roving into drafting machine
  • D01H5/18—Drafting machines or arrangements without fallers or like pinned bars
  • D01H5/70—Constructional features of drafting elements
  • D01H5/86—Aprons; Apron supports; Apron tensioning arrangements

Definitions

• the invention is concerned with apparatus for condensing a drafted fibre sliver in a condensation zone after the front roller pair on a drafting unit, where the condensation zone contains a suction element with a sliding surface with at least one suction slit essentially running in the direction of movement of the fibre sliver and a transport belt, which transports the fibre sliver over the sliding surface and is at least air-permeable over parts of its surface.
• the suction element has a sliding surface on the same side as the travel of the fibre sliver, cambered in the direction in which the fibre travels and is provided with a suction slit.
• An air-permeable transport belt is moved over this sliding surface, so transporting the fibre sliver.
• Beneath the suction element the transport belt loops round a transfer roller/which for its part is driven over a pair of gearwheels by a drive roller.
• a nipping roller presses from the top against the transport belt lying on the sliding surface to limit the condensation zone on the sliding surface.
• the disadvantage of this process is that the transport belt would have to have completely contradictory characteristics in order for the apparatus to function satisfactorily. On the one hand, it has to provide the highest possible degree of non-clinging qualities on the side touching the sliding surface, i.e. a low coefficient of friction. On the other hand, the same side of the transport belt has to provide the highest possible coefficient of friction and a low tendency to stick, in order to permit an adequate transfer of force through the transfer roller. If the coefficient of friction is not ideally set with the other parameters, which could be difficult to achieve, the result will either be insufficient drive movement with a high degree of slippage between the transfer roller and the transport belt, or the transport belt will move jerkily on the sliding surface as a result of too much friction.
• the transport belt is therefore under a high degree of tensile stress in the condensation zone, which in the long term will lead to elongation.
• the transport belt is under "thrust", so that there is a danger that excess length, which sets in with time, might extend to the condensation zone and there lead to defective support for the transport belt on the sliding surface. This, however, creates a situation where air can penetrate between the transport belt and the sliding surface laterally and can impair the condensation effect.
• the underlying task of the invention is therefore to create apparatus for condensing a drafted fibre sliver, where the drive system for the transport belt is guaranteed to be safe, subject to little wear and independent of the tension on the transport belt.
• Claims 2 to 12 contain further advantageous features.
• the apparatus that has been invented has the advantage over the current state of technology that the drive for the transport belt occurs independently of its tension.
• the transport belt can therefore be kept at a level of tension, which is ideal for the remaining functions, without any detrimental effects on the transmission of the drive torque.
• the sliding pairing between the transport belt and the sliding surface on the suction element is not adversely affected.
• the apron always sits precisely on the sliding surface as a result of the defined tension for the apron and the convex shape of the sliding surface. This means that a constant partial vacuum is achieved and air cannot penetrate the system laterally.
• Fig. 1 shows the outlet area of a drafting unit 1, as found on ring spinning machines.
• Three driven bottom rollers, 2, 3 and 4 are arranged on shafts that are not illustrated, by which three upper rollers, 6, 7 and 8 housed in a pressure arm 5 are driven.
• the bottom roller 4 and the upper roller 8 jointly form the front pair of rollers 9 on the drafting unit 1.
• the drafting of the fibre sliver 10, which has been fed fn, takes place in the drafting unit 1 up to this pair of front rollers 9 and this is a widely known process.
• This suction element 11, as well • as a guide roller 13, are both partly looped by an air-permeable transport belt 12.
• a guide roller 13 presses against a drive roller 14, which is linked to a motor drive unit, which is not illustrated.
• This drive roller 14 and the bottom rollers 2, 3 and 4 are preferably part of a drive shaft extending over several spinning positions or the complete machine length.
• the guide roller's 13 pressure on the drive roller 14 is created using a spring 15, which is attached at a retaining element 16, which is linked to the spinning machine frame.
• the spring 15 presses against the shaft 19, which - as is normal on spinning machines - carries the guide rollers 13 for two adjacent spinning points, and is locked in place temporarily at the retaining element 16 using a catch 20 which overlaps the retaining element's edge 7.
• the shaft itself 19 is not secured in a bearing, but simply rests on a catch 18 on the retaining element 16. This means that the guide roller 13 floats at right angles to the shaft 19.
• the spring 15, engaged between each two of the guide rollers 13, which are seated on the shaft 19, is so wide that it limits the axial mobility of the guide rollers 13.
• This upper roller mounting 23 is once again secured in the shaft 24 of the upper roller 4 of the front roller pair 9 held in the pressure arm 5 and can be removed.
• a spring 25 supported on the pressure arm 5 provides the required contact pressure for the nipping roller 22 on the suction element 11.
• the invention caters for a situation where the nipping roller 22 rests on the transport belt 12 with a low degree of active pressure amounting to roughly 1 to 2 daN. This means that it is possible to limit the condensation zone; the movement of the transport belt 12 on the suction element is not hindered, however.
• the nipping roller is also provided with a soft coating with a hardness in the 53° to 63° range on the Shore A hardness scale.
• the suction element 11 consists of a hollow section, preferably a drawn steel section, which extends over several, or preferably two spinning points and is sealed off on the front side in an advantageous manner by two sealing caps 27 made of plastic.
• a common source of partial vacuum which is not, however, illustrated, is assigned to all these spinning points via an extraction opening 26 on the suction element 11.
• the Hnk with the partial vacuum source is created via a suction channel, which is linked to the suction element 11 by means of a detachable rubber gasket.
• a suction slit 28 is arranged for each fibre sliver 10 in the area covered by the transport belt 12 (sliding surface).
• the surface of the suction element 11 is given additional treatment, at least in the area around the sliding surface, in order to achieve a low coefficient of friction.
• this can take place using e.g. shot peening or by modifying the surface.
• an extrusion press section made of aluminium is used, the surface is coated to guarantee both the required slide performance and the necessary hardness of the surface.
• the transport belt 12 has a coating with a low coefficient of friction on the side touching the sliding surface and a coating with a high coefficient of friction on the side not touching the sliding surface.
• the movement of the transport belt 12 can be greatly enhanced. Disadvantages, as found on familiar apparatus of this kind, are avoided.
• the inner side of the transport belt 12 is not used to transmit power and can therefore be fitted with good sliding characteristics.
• the drive movement is fed into the transport belt 12, by pressing the guide roller 13 against the drive roller 14 by means of the perpendicular force exerted by the spring 15.
• the spring 15 By providing the spring 15 with the correct dimensions, the normal force for the transmission of power is sufficiently large, but not too large. This feature prevents premature wear on the transport belt 12.
• the apparatus in the invention is designed in such a way that all the elements, which are used to condense the fibre sliver 10, can be assembled or removed at the spinning point without any great effort. This means that it is possible to use the spinning point both in the conventional sense and also for condensation spinning.
• the upper roller mounting 23 with the nipping roller 22 is detached from the pressure arm 5, and the guide roller 13 is released by freeing the spring 15, so that the suction element 11, the transport belt 12 and the guide roller 13 can be simply removed from the spinning point.
• the invention is concerned with apparatus for condensing a drafted. fibre sliver in a condensation zone after the front roller pair on a drafting unit, where the condensation zone contains a suction element with a sliding surface with at least one suction slit essentially running in the direction of movement of the fibre sliver and a transport belt, which transports the fibre sliver over the sliding surface and is at least air-permeable over parts of its surface.
• the underlying task of the invention is therefore to create apparatus for condensing a drafted fibre sliver, where the drive system for the transport belt is guaranteed to be safe, subject to little wear and independent of the tension on the transport belt.
• the invention can be used on spinning machines, especially ring spinning machines.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Textile Engineering (AREA)
• Spinning Or Twisting Of Yarns (AREA)
• Manufacture Of Alloys Or Alloy Compounds (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=28685198

Family Applications (1)

Country Status (6)

Families Citing this family (3)

Family Cites Families (4)

• 2002
  • 2002-04-19 DE DE10217669A patent/DE10217669A1/de not_active Withdrawn
• 2003
  • 2003-04-11 DE DE60330956T patent/DE60330956D1/de not_active Expired - Fee Related
  • 2003-04-11 EP EP03733008A patent/EP1497486B1/fr not_active Expired - Lifetime
  • 2003-04-11 WO PCT/IN2003/000155 patent/WO2003089701A2/fr not_active Ceased
  • 2003-04-11 CN CN03808821.5A patent/CN1646742B/zh not_active Expired - Fee Related
  • 2003-04-11 AT AT03733008T patent/ATE455194T1/de not_active IP Right Cessation
  • 2003-04-11 AU AU2003238672A patent/AU2003238672A1/en not_active Abandoned

Non-Patent Citations (1)

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