FIELD OF INVENTION

The present invention relates to an improved doffing arm arrangement for a spinning machine. More particularly, this invention relates to a doffing arm arrangement for a speed frame machine. While doffing process, said improved doffing arms can be moved simultaneously to and fro in the machine, with less time consumption.

BACKGROUND OF THE INVENTION

In textile field, the speed frame machines are being used for making roving, in the process of yarn manufacturing. The feed material is continuous fibre assembly which is in the form of sliver is fed from a sliver can. And then the sliver is linearly stretched to reduce the linear density by passing it through drafting zone.

Then some amount of twist is imparted into the drafted material by means of a flyer false twister. Further the roving material is wound on a package called bobbin. After completing the winding process, the full bobbin is replaced with an empty bobbin tubes using a doffing arrangement. The doffing arrangement comprises a plurality of doffing arm sections in which the plurality of doffing arms are arranged inclined and in parallel.

Said doffing arms hold the bobbin with help of a bobbin base; each doffing arm consists of a pair of such bobbin bases so as to hold two bobbins at a time.

Said doffing arm sections are arranged in a doffing frame, which comprises horizontal rail arrangement and vertical rail arrangement. Said horizontal rail arrangement is used for forward and backward movement of the doffing arm section and the up and down movement of the doffing arm section is executed by vertical rail arrangement. The vertical rail comprises a chain wheel driving mechanism for up and down movement of the doffing arm. The forward and backward movement of the doffing arm is controlled by a pneumatic drive system. Since the forward and backward movement is executed by the pneumatic drive, there is timing difference in the movement of the doffing arms between them. The doffing arms movement will not be a synchronized movement and they move with time lag between them. Hence there is chance of collision between the doffing arms sections.

In order to avoid the collision, the doffing arms are moved sequentially one after the other. Hence the time for doffing cycle is increased

OBJECT OF THE INVENTION

The principle object of the invention is to provide an improved arrangement for the automatic doffing arrangement in a textile spinning machine.

Another object of the present invention is to provide an doffing arrangement that can be moved simultaneously to and fro in the machine.

Yet another object of the invention is to reduce the time consumed in the process of doffing and meanwhile increasing the productivity.

SUMMARY OF THE INVENTION

According to the present invention, an improved doffing arm arrangement for textile spinning machine, like speed frame is developed. The improved doffing arm comprises a plurality of doffing arm section; the said doffing arm section helps in replacing the full roving bobbin by the empty bobbin tube during the doffing operation. The structural arrangement of the each doffing arm section has been changed in such a way it can overcome the above mentioned collision problem during the process of doffing. The collision is avoided by introducing an elbow doffing arm at very last position of each doffing arm sections as shown in the figure 3. In this arrangement, there is a moving clearance obtained between the doffing arms. Hence all the doffing arms can be moved simultaneously without collision.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure-1 is a schematic view of a doffing arrangement in the speed frame machine.

Figure-2 shows the top view of the existing doffing arm arrangement according to the known art.

Figure-3 illustrates the schematic plane view of the improved doffing arm arrangement according to the invention.

Figure-4 shows the exponential illustration of the improved doffing arm according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

The Figure.1 shows the schematic view of a doffing arrangement in a speed frame machine, wherein the frame (1) holds the doffing arrangement which comprises plurality of doffing arm sections (4 & 4"). The frame (1) further comprises a horizontal rail arrangement (2) and a vertical rail arrangement (3). As shown in Figure-2, the doffing arm sections (4 & 4') are mounted in the vertical rail with the help of a wheel (8). The up and down movement of the doffing arm is executed by the vertical rail arrangement. The horizontal rail arrangement (2) comprises of a pneumatic drive mechanism (not shown), which drives the doffing arm section (4/4') in a forward and backward direction (shown by arrows) during the doffing operation.

The Figure-2 shows the top view of the existing doffing arm arrangement, which comprises a plurality of doffing arms (5). These doffing arms (5) are arranged inclined and in parallel to each other. This doffing arm helps in exchanging the full bobbin with the empty bobbin tube; each doffing arm comprises a pair of bobbin base (6) which holds the bobbin during the doffing process. Here the figure also shows the shaded area (7) where the problem of collision occurs.

The Figure-3 illustrates the schematic plane view of the improved doffing arm arrangement according to the present invention wherein the space (9) between the adjacent doffing arm sections (4 & 4') is provided with the help of a improved doffing arm i.e., providing elbow doffing arm (10). Said elbow doffing arm (10) is provided at very last position of each doffing arm sections (4/4'). Figure-4 of the invention shows the exponential view of the elbow doffing arm (10) comprises a inclined portion (11) and straight portion (12) wherein the said inclined portion (11) is provided in parallel with preceding doffing arm. Hence the parallelism between the elbow doffing arm (10) and preceding doffing arm is maintained similar to other preceding doffing arms. This helps the bobbin base (6) of elbow doffing arm (10) to hold the bobbins in relation with spindle position.

The elbow doffing arm (10) provides space between the nearby doffing arm section, and thereby moving clearance is obtained. Hence the doffing arm sections (4/4') can be moved simultaneously with out any collision during the doffing action. Therefore the time required for the completion of each doffing process is reduced and thereby leads to enhanced productivity of the speed frame machine. Though the present invention shown herein are only exemplary, further embodiments are also possible within the boundary of the invention.

We Claim

1. An improved doffing arm arrangement for spinning machines comprises a plurality of doffing arm sections (4, 4') in which plurality of doffing arms (5) are arranged inclined and parallel to each other; said doffing arm helps in replacing the full bobbin with the empty bobbin tube during the doffing operation; wherein an elbow doffing arm (10) is provided in each doffing arm sections (4, 4').

2. An improved doffing arm arrangement for spinning machines as claimed in claim -1, wherein the elbow doffing arm (10) is provided at very last position of each doffing arm sections (4/4').

3. An improved doffing arm arrangement for spinning machines as claimed in claim -1, wherein elbow doffing arm (10) comprises a inclined portion (11) and straight portion (12).

4. An improved doffing arm arrangement for spinning machines as claimed in claim - 3, wherein the inclined portion (11) is provided in parallel with preceding doffing arm.

5. An improved doffing arm arrangement for spinning machines as claimed in claim - 1, wherein each doffing arm comprises a pair of bobbin base (6).

6. An improved doffing arm arrangement for spinning machines as claimed in claim -1, wherein the elbow doffing arm (10) provides space between the nearby doffing arm sections (4, 4') and thereby moving clearance is obtained.