FIELD OF THE INVENTION

The present invention relates to the doffing arrangement of textile machines. Particularly, this invention relates to doffing arrangement of textile roving frames. More particularly, the present invention relates to safety device for auto doffer arrangements of textile roving frames.

BACKGROUND OF THE INVENTION

Textile roving frame machines commercially termed as speed frame machines are used to produce roving package from feed sliver. The said sliver is an outcome product of the preceding spinning preparatory machine which is generally a draw frame machine. Sliver delivered from the draw frame machine is stored in a sliver-can and sent to the successive speed frame machine of the textile spinning industry. There a plurality of such sliver cans are being arranged below the creel of the speed frame.

Then the slivers are fed through the creel guide rollers into the drafting unit of the speed frame machine. There the drafted sliver is converted into a fibre band of smaller diameter than the feed sliver. Then the said fibre band is given a false twist when it successively passes through the false twister of the flyer device. The said flyer device normally rotates at a speed of more than 1200 rpm. A spindle is drivingly associated with the flyer device, which holds the empty tube for winding the said twisted fibre band on it. This twisted fibre band is generally termed as roving. The said roving is the feed material to the successive ring spinning machine where the roving is converted into yarn.

Textile roving frame machines comprises doffing arrangement for replacing full roving packages. The roving material which is wound on a package called bobbin, is replaced with an empty bobbin tube using said doffing arrangement. The doffing arrangement comprises a plurality of doffing arm sections in which the said plurality of doffing arms are arranged parallel to each other throughout the length of the machine frame.

The said doffing arm sections are arranged in a doffing frame, which comprises horizontal rail arrangement and vertical rail arrangement. The said horizontal rail arrangement is used for forward and backward movement of the doffing arm section and the said vertical rail arrangement is used for the up and down movement of the doffing arm section. The vertical rail comprises a chain wheel driving mechanism for up and down movement of the doffing arm.

It is common for the said chain to break down due to overload and fatigue over a period of time. The existing doffing arrangement comprises device for avoiding the fall of doffing arms during idle or parking condition. But till date, no such safety device is available in the speed frame doffing arrangement to avoid falling down of the doffing arms during doffing condition in case the chain is cut down due to overload. In order to eliminate the accidents and untoward incidents in auto doffer arrangements of roving frames, the present invention provides an improved safety device for doffing arm arrangements during both doffing and idle (parking) condition.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide a safety device for auto doffer arrangements in textile roving frame machines.

It is another object of the present invention to provide a device which avoids accidents in auto doffer arrangements of textile roving frame machines.

It is yet another object of the present invention to provide a safety device which avoids accidents in auto doffer arrangements of textile roving frame machines both during doffing and parking positions.

SUMMARY OF THE INVENTION

According to an embodiment of the present invention, an improved safety device arrangement is provided for the doffing arm arrangements of auto doffers in textile roving frame machines. The said roving frame comprises plurality of doffing arms; said doffing arms being slidably mounted on vertical pillars; characterized in that safety means are provided for avoiding fall down of said doffing arms. Advantageously, the safety means is in the form of at least an extended flat support plate at the ends of each doffing arm. The said flat support plates are fixed to said doffing arms in a linear manner.

According to an embodiment of the present invention, said flat support plates ensures the doffing arm rests safely on the similar flat support plate of the adjacent doffing arm in case chain is cut. Advantageously, the flat support plate arrangement at the right end of one doffing arm is positioned linearly with respect to the flat support plate arrangement at the left end of next doffing arm such that the said flat support plates are in different planes.
The doffing arm (A) with flat support plate (6') rests on the flat support plate (6'") of the adjacent doffing arm (B) in case the chain (3) of doffing arm (A) is cut. The doffing arm (B) with flat support plate (6") rests on the flat support plate (6') of the preceding doffing arm (A) in case the chain (3) of doffing arm (B) is cut.

According to an embodiment of the present invention, double chain drives are provided at the left end and right end of the machine. Further, a sensor emitter is provided at the left end and a sensor receiver is provided at the right end of the machine in same plane. A blocking plate is provided along the length of the machine in between the emitter and receiver.

The above said safety device arrangement continues similarly to all doffing arms throughout the length of the machine frame based on the length of the machine frame (number of spindles). According to this invention, the doffing arm will not fall down in case chain is cut due to overload during doffing and avoids accidents.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows the schematic illustration of doffing arrangement in roving frames with safety device according to the present invention.

Figure 1a shows the exploded view of the section shown in arrow mark in Figure 1 depicting the safety device according to the present invention.

Figure 2 shows the schematic illustration of doffing arrangement in roving frames with additional safety device according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to Figure 1 and 1a, the plurality of doffing arms (1) are mounted in the doffing arrangement section-wise throughout the length of the roving frame. The doffing arms (1) are slidably mounted on the vertical pillars (2) through chain (3) drive mechanism. The drive shaft (4) is rotated to provide movement to the chain (3) linkage. The drive shaft (4) is driven by a motor (5). The chain (3) link provides vertical movement to the doffing arms (1) up and down to enable doffing operation.
In existing doffing arrangements, in case the chain (3) is cut at any of the vertical pillars (2) due to overload and / or fatigue, the respective doffing arm (1) will fall down leading to accident. To avoid such untoward incidents, the doffing arms (1) are provided with at least an extended flat support plate arrangement (6) at the ends in a linear manner to the doffing arms (1) as shown in the figures.

The extended flat arrangement shall be preferably in the form of a support plate (6) made of steel or any load withstanding material. The forthcoming description is explained in relation to two adjacent doffing arms (A & B). The right end of first doffing arm (A) is provisioned with a single support plate (6'). The support plate (6') is fixed to the doffing arm (1) using bolts firmly / welded in a linear manner as shown in the figures. The left end of the adjacent (next) doffing arm (B) is provisioned with two support plates (6" & 6,M), one plate (6") being fixed at the top of the doffing arm (B) and the other plate (6m) being fixed at the lower end of doffing arm (B) using bolts / welded. The assembled condition is shown clearly in the figures. In case the chain (3) link of first doffing arm (A) is cut, the support plate (6') provided at the right end of said doffing arm (A) will rest on the bottom support plate (6'") provided at the left end of adjacent doffing arm (B). The said doffing arm (A) safely rests on the support plate (6'") of the adjacent doffing arm (B).

In case the chain (3) link of second doffing arm (B) is cut, the top support plate (6") provided at the left end of said doffing arm (B) will rest on the support plate (6') provided at the right end of doffing arm (A). The support plates (6', 6" & 6m) provided at the ends of the doffing arms (1) are very simple and easy to assemble. The similar support plate arrangement (6) shall be used in each and every doffing arms (1) throughout the length of the roving frame based on the number of spindles.

Advantageously, the said support plates (6) shall be provisioned in any combinations as follows:

one support plate (6') at the right end of first doffing arm (A) and two support plates (6" & 6'") at the left end of next / adjacent doffing arm (B) and vice versa throughout the length of the machine frame.

Advantageously, the doffing arms (1) at the left most machine end (7A) and right most machine end (7B) are provided with double chain (3) link drives to enable better strength and load bearing capacity. In case any one of the chain (3) is cut, the additional chain will hold the doffing arm without falling down during doffing operation. Subsequently, the cut chain shall be replaced.

Referring to Figure 2, the doffing arrangement in roving frame is provided with additional safety device. According to this embodiment, a sensor emitter (8) is fixed at the left end (7A) of the machine in doffing arm support bracket as shown in the figure. A sensor receiver (9) is fixed at the other end / right end (7B) of the machine in doffing arm support bracket as shown. The sensor emitter (8) and receiver (9) are in same line / plane.

In case the chain (3) of the doffing arm (A) cuts, the support plate (6') of said doffing arm (A) will rest on support plate (6"') of adjacent doffing arm (B). On the other hand, if chain (3) of doffing arm (B) cuts, the support plate (6") of said doffing arm (B) will rest on the support plate (6') of the preceding doffing arm (A). In both the above cases, the rays from emitter (8) is not received by the receiver (9) as the rays are blocked by the doffing arm (1). The fault alarm is activated.and the machine is immediately stopped to replace the cut chain (3).

In case the chain (3) cuts at any of the ends (7A, 7B) of the machine, the doffing arm (1) willbe supported by the additional chain. In this case, the rays from the sensor will be blocked by the blocking plate (10) arrangement provided along the length of the machine frame as shown in the figure, as the doffing arm (1) is misaligned. The fault alarm is activated and the machine is immediately stopped to replace the cut chain (3).

Thus, the safety device according to the invention provides a simple and easy arrangement to avoid accidents in the mill site during doffing operation of roving frame machines. Advantageously, accidental damages such as fatalities, injuries, productivity losses are greatly avoided during both doffing operation and idle / parking condition in case the chain link is cut down.

In view of the present disclosure which describes the present invention, all changes, modifications and variations within the meaning and range of equivalency are considered within the scope and spirit of the invention.

We claim:

1. A doffing arrangement for roving frame, said roving frame comprising plurality of doffing arms (1); said doffing arms (1) being slidably mounted on vertical pillars (2); characterized in that safety means (6) are provided for avoiding fall down of said doffing arms (1).

2. The doffing arrangement as claimed in claim 1, wherein the safety means (6) is in the form of at least an extended flat support plate (6\ 6", 6'") at the ends of each doffing arm (1).

3. The doffing arrangement as. claimed in claim 2, wherein said flat support plates (6\ 6", 6,H) are fixed to said doffing arms (1) in a linear manner.

4. The doffing arrangement as claimed in claim 2, wherein said flat support plates (6\ 6", 6'") ensures the doffing arm (1) rests safely on the similar flat support plate (6\ 6", 6'") of the adjacent doffing arm (1) in case chain (3) is cut.

5. The doffing arrangement as claimed in claim 4, wherein flat support plate arrangement (6') at the right end of one doffing arm (A) is positioned linearly with respect to the flat support plate arrangement (6" & 6'") at the left end of next doffing arm (B) such that the said flat support plates (6', 6" & 6'") are in different planes.

6. The doffing arrangement as claimed in claim 5, wherein the doffing arm (A) with flat support plate (6') rests on the flat support plate (6'") of the adjacent doffing arm (B) in case the chain (3) of doffing arm (A) is cut.

7. The doffing arrangement as claimed in claim 5, wherein the doffing arm (B) with flat support plate (6") rests on the flat support plate (6') of the preceding doffing arm (A) in case the chain (3) of doffing arm (B) is cut.

8. The doffing arrangement as claimed in claim 1, wherein double chain (3) drives are provided at the left end (7A) and right end (7B) of the machine.

9. The doffing arrangement as claimed in claim 1, wherein sensor emitter (8) is provided at the left end (7A) and sensor receiver (9) is provided at the right end (7B) of the machine in same plane.

10. The doffing arrangement as claimed in claim 9, wherein blocking plate (10) is provided along the length of the machine in between the emitter (8) and receiver (9).