FIELD OF THE INVENTION

The present invention relates to an improved lap winding apparatus for use in spinning preparatory process of textile fibres. This invention specifically deals with a lap winding apparatus of lap forming machine for producing a lap of fibre sheet. More particularly, the invention is concerned to lap winding rollers of textile lap forming machine.

BACKGROUND OF THE INVENTION

In textile spinning mills a lap forming machine is used for producing laps of fibre sheet. And as a succession process these laps are being used as a feed material for combing machines. The slivers arranged in the creel are doubled and drafted as per requirement by the drafting system of the lap forming machine. The drafted slivers delivered in the form of lap sheet are subsequently combined together and delivered to the calendering rollers where the lap sheet is compacted and delivered to the lap head.

The lap head comprising a pair of juxtaposed lap rollers adapted to wind a lap on a spool therein, a pair of vertical arms disposed on either side of said lap rollers. The upper end of which are provided with a pair of lap discs facing each other for clamping said spool therebetween, the lap is wound on the lap spool which is being driven by the frictional contact of said lap rollers. These lap rollers are being driven by the drive system of the lap forming machine. Aforesaid arms being adapted to ascend in response to the thickness of the lap wound on said spool. After the spool has been wound with a full lap, it is being exchanged simultaneously with a new spool at a position above the surface of said lap rollers. Then the full lap is being pushed out by means of a spool supply means from said position and to be held between one of lap rollers. Subsequently the lap is being severed during the further slow rotation of lap rollers alone, and thereafter said spool is doffed to the outside from said rollers without stopping the machine.

In the known lap forming machines, the lap rollers are equal in diameter and having equal number of longitudinal grooves on their peripheral surface. And also it has been noted that instead of pair of grooved lap rollers, some of the lap forming machines are provided with a grooved roller and a plain surfaced roller juxtaposed to each other. Said longitudinal grooves helps to possess necessary frictional force that is required to hold the lap between lap rollers and in turn to assist a proper winding. With these arrangements a balloon formation takes place in the lap while going for higher operating speeds and also formation of blisters occurs on the lap roll during initial winding. Moreover it is not possible to run the machine for higher lap length. During unwinding of lap roll It has been noted that, the lap hairiness is more which affects the quality and appearance of fibre sheet that is being unwounded. In order to overcome the above limitations it is posed to come through a lap forming apparatus which can give better lap quality, higher lap length and better appearance even during higher operating speed.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide a lap winding apparatus which improves the grip between winding spool and lap rollers thereby enhancing the quality and appearance of lap roll.

It is an another object of the invention to provide a lap winding apparatus which imparts better air escape thereby avoiding blister formation during winding of lap roll. It is yet another object of the present invention to adapt better draft control and nullifying the balloon formation during higher operative speed of lap roll winding.

SUMMARY OF THE INVENTION

According to the present invention the lap forming machine is provided with improved grooved lap rollers wherein the total number of grooves on their peripheral surface is not equal to each other. Both lap rollers are having same diameter but number of grooves on their surface will be different. On the other hand, different diameter lap rollers with same number of grooves or different number of grooves can be provided. For example, the front lap roller comprises more number of grooves whereas the rear one comprising of less number of grooves or vice-versa. Due to this difference, the winding spool is held firmly by gripping force of both rollers and can be rotated without any slippage.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Fig-1 represents the schematic view of the improved lap winding apparatus of a textile lap forming machine according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The improved lap winding apparatus of a textile lap forming machine is shown in Fig-1 wherein the lap head (1) comprising of calendering zone (2) and winding zone (3). Calendering zone (2) comprises plurality of calender rollers (5,6,7& 8) for compressing the drafted fibre sheet (4) into more compact. And lap winding zone (3) is provided with a pair of juxtaposed unidirectionally driven lap rollers (9,10) adapted to wind a lap roll (12) on a spool (11) therein, and said lap rollers (9,10) gets the drive from driving system (not shown) of lap forming machine. Herein the front lap roller (10) and rear lap roller (9) are of having same diameter and are provided with plurality longitudinal grooves (13) on their peripheral surfaces. Therein a unequal number of groove is maintained between lap rollers (9&10), for example front lap roller (10) is provided with more number of grooves (13) say 366 nos whereas, the rear lap roller (9) is provided with less number of grooves say 240 nos. As an alternate embodiment it is also possible to provide unequal diameter lap rollers with equal number of grooves or unequal number of grooves with same constructional features.

Fibre sheet (4) which is delivered from the drafting zone (not shown) is introduced into the lap head (1) and runs through the calendering zone (2). Due to the calendering action of calender rollers (5,6,7& 8) the fibre sheet (4) gets compressed into more compact and then passed onto the rear lap roller (9) of winding zone (3). In order to wind the lap (12), a spool (11) is being clamped between a pair of lap discs (not shown) and is placed onto the gap between the rear lap roller (9) and front lap roller (10) of winding zone (3) and is frictionally driven by said rollers. Since the lap rollers (9,10) are provided with differed number of grooves (13) thereon, the spool (11) is held firmly therein and rotated without any slippage. Adequate winding pressure is maintained on the lap roll (12) by pair of vertical arms incorporated with piston and cylinder means disposed on either side of said lap rollers which is not shown. After reaching the predetermined values such as lap length, lap roll diameter or lap weight, the fibre sheet (4) is being severed and lap roll (12) is doffed and replaced with an empty spool (11) for next winding cycle to begin.

Since the lap rollers (9,10) are provided with different number of grooves (13), an adequate frictional force is imposed on the lap roll (12) which avoids balloon formation and also provides a fine draft control on the lap. Due to this groove arrangement a better air escape takes place between lap rollers (9, 10) and the lap roll (12) which avoids blister formation during initial winding and better grip avails between winding spool and both lap rollers . Furtherance the machine can be operated for winding more lap length even at high winding speed than existing art. Moreover a lap roll (12) thus wound results in less hairiness and in turn improved quality and enhanced lap appearance.

The apparatus described herein delivers positive results even any of lap roller (9 or 10) is provided with more number of longitudinal grooves (13) than its juxtaposed one, and said grooves (13) may be in form of straight line, herring bone, helical or diagonal.

The embodiments shown herein are only exemplary. Further embodiments are possible within the scope of the invention.

We Claim:

1. An improved lap winding apparatus for a lap forming machine comprises a lap head (1) having a plurality of calender rollers (5,6,7& 8) in calendering zone and a pair of lap rollers (9,10) to wind a lap roll (12) on a spool (11), characterized in that said lap rollers (9, 10) are provided with unequal number of grooves (13).

2. An improved lap winding apparatus for a lap forming machine according to claim 1, characterized in that said grooves (13) may be in form of straight line, herring bone, helical or diagonal.

3. An improved lap winding apparatus for a lap forming machine according to claim 1, characterized in that said lap rollers (9,10) are equal in diameter.

4. An improved lap winding apparatus for a lap forming machine according to claim 1, characterized in that said lap roller (10) comprises more number of grooves whereas the another lap roller (9) comprising of less number of grooves or vice-versa.

5. An improved lap winding apparatus for a lap forming machine according to claim 1, characterized in that said lap roller (10) can be larger in diameter whereas the another lap roller (9) is comparatively smaller in diameter or vice-versa.

6. An improved lap winding apparatus for a lap forming machine comprises a lap head (1) having a plurality of calender rollers (5,6,7& 8) in calendering zone and a pair of lap rollers (9,10) to wind a lap roll

(12) on a spool (11), characterized in that said lap rollers (9, 10) are unequal in diameter and provided with equal or unequal number of grooves (13).

7. An improved lap winding apparatus for a lap forming machine substantially herein described and illustrated with reference to the accompanying figure.