DESC:FIELD OF THE INVENTION
The present disclosure relates to a piecing system to carry out a piecing operation in a spinning machine. More particularly, the present disclosure provides a piecing system and method to carry out a piecing operation for air jet spinning machines.

BACKGROUND OF THE INVENTION
Generally, in spinning machines when yarn breakage occurs a piecing operation is carried out to join the broken yarn to feed fibres to resume the spinning operation. In air jet spinning machines yarn breakage is a major concern as it affects production and efficiency of the entire spinning machine. Piecing in air jet spinning machines is carried out using suction arms mounted on travelling service units. The travelling service units position themselves in front of the spinning station having broken yarn to carry out the piecing operation. The travelling service units need to travel in front of the entire length of the spinning stations provided in the spinning machine to reach the spinning station having broken yarn making it a time consuming process. In case of multiple yarn breakages and frequent yarn breaking in a spinning machine a plurality of spinning stations remain idle when the piecing operations are carried out one by one on different spinning stations.
The problem of high number of idle spinning stations can be solved by individual piecing systems on each spinning station as disclosed in US6804945. In individual piecing systems suction arms are pivoted on the spinning machines to deliver the broken yarn to a spinning unit. In individual piecing unit the yarn has to be placed exactly into the centre of the spinning unit, thereby requiring additional centering plates to guide the yarn. During a sequence of transferring yarn from the suction arm to the spinning unit in individual piecing units there is high possibility of collisions between spinning elements and yarn transfer elements in case of failure of any component. The collisions cause damage and lead to frequent machine downtimes and frequent replacement of components, thereby increasing maintenance and operating costs.
Therefore, there is a need for a system for carrying out piecing operations without affecting efficiency of the machine while not requiring additional components.

SUMMARY OF THE INVENTION
In the first aspect the present invention provides a piecing system for a piecing operation of a spinning machine. The piecing system includes a suction arm on each individual spinning station of the spinning machine, an intermediate yarn guide, a hook element and a scissor. The suction arm is connected to a controller of the spinning station. The suction arm has a suction mouth at one end for picking up a broken yarn end and is configured to pivot between a plurality of positions to pick up a yarn end after a yarn breakage to deliver the yarn end to a pair of delivery rollers of the spinning machine. An intermediate yarn guide pivotable between at least two positions according to the position of the suction arm, is configured to guide the yarn into the pair of delivery rollers of the spinning machine. The intermediate yarn guide is mounted on one of the delivery rollers of the spinning machine mounted along with an actuator. A hook element is mounted on an outer surface of the suction arm, to hold a loop of yarn formed by the combined motion of the suction arm and intermediate yarn guide. A scissor is mounted along with the hook element on the outer surface of the suction arm, for cutting excess yarn after the piecing operation is completed.
According to the present invention, the spinning machine is a textile air jet spinning machine having a plurality of spinning stations.
According to the present invention, the plurality of positions of the suction arm includes at least 4 positions, namely, a first position or home position, a second position, a third position and a fourth position.
According to the present invention, the hook element and the scissor are mounted on the outer surface of the suction arm with the same bracket.
According to the present invention, the positions of the intermediate yarn guide include a home position and a next position.
According to the present invention, the loop of yarn held by the suction arm and intermediate yarn guide is transferred to the hook element as a result of the combined motions of the suction arm and intermediate yarn guide.
In the second aspect, the present invention provides a spinning machine comprising a plurality of spinning stations, each having a spinning unit, a piecing system of the first aspect mounted on each spinning unit to carry out a piecing operation when a yarn breakage occurs and a yarn monitoring device to detect the breakage of yarn and send a signal to a controller of the spinning machine.
In the third aspect the present invention provides a method of piecing in a spinning machine comprising the following steps. Detecting, by a yarn monitoring device of the spinning machine, a yarn breakage on a spinning station. Pausing spinning operation, of the spinning station with yarn breakage. Pivoting the suction arm towards a package, from a first position to a second position to pick up the broken yarn end by a suction mouth of the suction arm upon receiving the signal from the yarn monitoring device. Pivoting the suction arm to a third position along with the yarn end. Actuating an actuator to pivot an intermediate yarn guide forward from a home position to next position while the suction arm pivots from the second position to the third position to receive the yarn from the suction arm. Actuating the actuator to pivot the intermediate yarn guide to pivot backward to the home position once the yarn is received from the suction arm, thereby forming a loop of yarn between the intermediate yarn guide and suction arm. Pivoting the suction arm to the first position from the third position once the intermediate yarn guide is pivoted to the home position, thereby transferring the loop of yarn to a hook element of the suction arm. Actuating the actuator to pivot the intermediate yarn guide to the next position. Pivoting the suction arm to a fourth position thereby releasing the loop formed between the suction arm and intermediate yarn guide. Cutting, by a scissor of the suction arm additional yarn between the suction arm and package. Pulling tail yarn end into spinning unit by suction around the spinning unit and resuming the spinning operation of the spinning station. Pivoting the suction arm to the first position once the spinning operation resumes.

BRIEF DESCRIPTION OF THE DRAWING
The foregoing and other features of embodiments of the present invention will become more apparent from the following detailed description of embodiments when read in conjunction with the accompanying drawings. In the drawings, like reference numerals refer to like elements.
Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it is not intended to limit the scope of the invention to these embodiments.
FIG. 1 illustrates a schematic view of a pair of piecing systems on a pair of spinning stations of the spinning machine, according to the present invention, and
FIG. 2a-2j illustrate a perspective view of a step by step working of the piecing system, according to the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION.
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawings.
Embodiments are provided to thoroughly and fully convey the scope of the present disclosure to a person skilled in the art. Numerous details are set forth relating to specific components to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
References in the present disclosure to “one embodiment” or “an embodiment” mean that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in an embodiment” or “in an implementation” in various places in the specification are not necessarily all referring to the same embodiment or implementation.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises,” “comprising,” “consists,” “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated elements, modules, units and/or components, but do not forbid the presence or addition of one or more other elements, components, and/or groups thereof.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
FIG. 1 illustrates a schematic view of a piecing system (150) on a spinning station (102) of the spinning machine (100) according to the present disclosure. The piecing system (150) includes a suction arm (104) having a suction mouth (106), an intermediate yarn guide (108), a hook element (110) on an outer surface (112) of the suction arm (104) and a scissor (not shown) on the outer surface (112) of the suction arm (104).
The suction arm (104) is pivotably attached to each spinning station (102) of the spinning machine (100). Each individual suction arm (104) has the suction mouth (106) at one end for picking up a broken yarn end (no shown. The suction arm (104) is connected to a controller (not shown) of the spinning machine (100). The suction arm (104) is configured to pivot between a plurality of positions to pick up the yarn end after a yarn breakage to deliver the yarn end to a pair of delivery rollers (116) of the spinning machine (100). The suction arm (104) is configured to pivot between at least 4 positions (S1, S2, S3, S4), namely, a first position or home position (S1), a second position (S2), a third position (S3) and a fourth position (S4). The controller of the spinning machine (100) is configured to pivot the suction arm (104) between the different positions (S1, S2, S3, S4). It should be noted that the suction arm (104) can be pivoted between more positions without limiting the scope of what is disclosed.
The intermediate yarn guide (108) is mounted on one of the delivery rollers (116) of the spinning machine (100). The intermediate yarn guide (108) is mounted along with an actuator (118) configured to pivot the intermediate yarn guide (108). The intermediate yarn guide (108) is connected to the controller of the spinning machine (100). The intermediate yarn guide (108) is pivotable between at least two positions (Y1, Y2) according to the position of the suction arm (104), configured to guide the yarn (114) into the pair of delivery rollers (116) of the spinning machine (100). The intermediate yarn guide (108) pivots between a home position (Y1) and a next position (Y2). It should be noted that the intermediate yarn guide (108) can pivot between any other positions without limiting the scope of what is disclosed.
The hook element (110) is mounted on the outer surface (112) of the suction arm (104). The hook element (110) holds a loop (120) of yarn (114) formed by the combined motion of the suction arm (104) and the intermediate yarn guide (108). The loop (120) of yarn (114) held by the suction arm (104) and intermediate yarn guide (108) is transferred to the hook element (110) as a result of the combined motions of the suction arm (104) and intermediate yarn guide (108).
The scissor is mounted along with the hook element (110) on the outer surface (112) of the suction arm (104). The scissor enables cutting of additional yarn (114) when piecing operation ends. The hook element (110) and the scissor are mounted on the outer surface (112) of the suction arm (104) with the same bracket. It should be noted that the scissor can be mounted using any other method without limiting the scope of what is disclosed.
The spinning machine (100) includes the spinning station (102) having a spinning unit (103), the piecing system (150) to carry out a piecing operation when a yarn breakage occurs, and a yarn monitoring device configured to detect a breakage of yarn (114) and send a signal to the controller of the spinning machine (100).
The suction arm (104) and the intermediate yarn guide (108) are configured to pivot in such a manner that the combined motion of the suction arm (104) and the actuation of the intermediate yarn guide (108) bring about the completion of a piecing operation. The piecing system (150) carries out the piecing operation using a method. The method contains the following steps.
Detecting, by a yarn monitoring device (not shown) of the spinning machine (100), a yarn breakage on a spinning station (102). Pausing spinning operation, of the spinning station (102) with yarn breakage. Pivoting the suction arm (104) towards a package, from a first position or home position (S1) to a second position (S2) to pick up the broken yarn end by the suction mouth (106) of the suction arm (104) upon receiving the signal from the yarn monitoring device. Pivoting the suction arm (104) to a third position (S3) along with the yarn end. Actuating an actuator (118) to pivot an intermediate yarn guide (108) forward from a home position (Y1) to a next position (Y2) while the suction arm (104) pivots from the second position (S2) to the third position (S3) to receive the yarn (114) from the suction arm (104). Actuating the actuator (118) to pivot the intermediate yarn guide (108) to pivot backward to the home position (Y1) once the yarn (114) is received from the suction arm (104), thereby forming a loop (120) of yarn (114) between the intermediate yarn guide (108) and suction arm (104). Pivoting the suction arm (104) to the first position from the third position (S3) once the intermediate yarn guide (108) is pivoted to the home position (Y1), thereby transferring the loop (120) of yarn (114) to a hook element (110) of the suction arm (104). Actuating the actuator (118) to pivot the intermediate yarn guide (108) to the next position (Y2). Pivoting the suction arm (104) to a fourth position (S4) thereby releasing the loop (120) formed between the suction arm (104) and intermediate yarn guide (108). Cutting, by a scissor of the suction arm (104) additional yarn (114) between the suction arm (104) and package. Pulling tail yarn end into spinning unit (103) by suction around the spinning unit (103) and resuming the spinning operation of the spinning station (102). Pivoting the suction arm (104) to the first position once the spinning operation resumes.
As illustrated in FIG. 2a the suction arm (104) is at a first position or home position (S1) and the intermediate yarn guide (108) is at a home position (Y1).
When yarn breakage is detected by the yarn monitoring device, the suction arm (104) is pivoted to a second position (S2) to pick up the broken yarn end as illustrated in FIG. 2b.
After the yarn end is picked up by the suction mouth (106) using negative pressure as illustrated in FIG. 2c the suction arm (104) is pivoted to the third position (S3) as illustrated in FIG. 2d.
While the suction arm (104) is pivoted to the third position (S3) the intermediate yarn guide (108) is pivoted to a next position (Y2) from the home position (Y1) as illustrated in FIG. 2e.
The suction arm (104) is then pivoted to the first position (S1) as illustrated in FIG. 2g thereby forming a loop (120) of yarn (114) with the intermediate yarn guide (108).
The loop (120) of yarn (114) is transferred to the hook element (110) as illustrated in FIG. 2h.
The yarn (114) is then delivered to the spinning unit (103) of the spinning station (102) by pivoting the suction arm (104) to a fourth position (S4) as illustrated in FIG. 2i. The excess yarn (114) is cut by the scissor. The actuator (118) actuates the intermediate yarn guide (108) along with the delivery roller (116) thereby allowing ease of placement of the yarn (114) in between the delivery rollers (116) as illustrated in FIGS. 2h and 2i. The end of yarn is sucked into the spinning unit (103) of the spinning station (102) by suction.
The suction arm (104) is pivoted back to the first position or home position (S1) and the intermediate yarn guide (108) is actuated back to home position (Y1) once the spinning operation is resumed as illustrated in FIG. 2j.
The entire process as described above in reference to FIGS. 2a-2j is completed within 10-20 seconds. The present invention provides an advantage of reduction in piecing time due to the precise movements of the suction arm and intermediate yarn guide. The reduction in piecing operation time enables less negative pressure to be used by the suction arm. the reduction in usage of negative pressure reduces power consumption.
The present invention also provides advantage of reduced operating and maintenance costs as the precise movements of the suction arm and intermediate yarn guide ensure yarn is delivered precisely and collisions are avoided thereby eliminating the need for components such as centering plates. Also, the reduced possibility of collisions also eliminates regular component change due to damage caused by collisions. The individual piecing systems on each spinning station reduce downtime of the spinning machine thereby ensuring productivity and efficiency is not affected.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
Any discussion of devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
,CLAIMS:
1. A piecing system (150) for a piecing operation of a spinning machine (100), the piecing system (150) comprising:
a suction arm (104) on each individual spinning station (102) of the spinning machine (100), the suction arm (104) connected to a controller of the spinning station (102), the suction arm (104) having a suction mouth (106) at one end for picking up a broken yarn end; said suction arm (104) configured to pivot between a plurality of positions to pick up a yarn end after a yarn breakage to deliver the yarn end to a pair of delivery rollers (116) of the spinning machine (100);
an intermediate yarn guide (108) pivotable between at least two positions according to the position of the suction arm (104), configured to guide the yarn (114) into the pair of delivery rollers (116) of the spinning machine (100), mounted on one of the delivery rollers (116) of the spinning machine (100) mounted along with an actuator (118);
a hook element (110) mounted on an outer surface (112) of the suction arm (104), to hold a loop (120) of yarn (114) formed by the combined motion of the suction arm (104) and intermediate yarn guide (108); and
a scissor mounted along with the hook element (110) on the outer surface (112) of the suction arm (104), for cutting excess yarn (114) after the piecing operation is completed.
2. The piecing system (150) as claimed in claim 1, wherein the spinning machine (100) is a textile air jet spinning machine (100) having a plurality of spinning stations (102).
3. The piecing system (150) as claimed in claim 1, wherein the plurality of positions of the suction arm (104) include at least 4 positions, namely, a first position or home position (S1), a second position (S2), a third position (S3) and a fourth position (S4).
4. The piecing system (150) as claimed in claim 1, wherein the hook element (110) and the scissor are mounted on the outer surface (112) of the suction arm (104) with the same bracket.
5. The piecing system (150) as claimed in claim 1, wherein the positions of the intermediate yarn guide (108) include a home position (Y1) and a next position (Y2).
6. The piecing system (150) as claimed in claim 1, wherein the loop (120) of yarn (114) held by the suction arm (104) and intermediate yarn guide (108) is transferred to the hook element (110) as a result of the combined motions of the suction arm (104) and intermediate yarn guide (108).

7. A spinning machine (100), comprising:
a plurality of spinning stations (102), each spinning station having a spinning unit (103);
a piecing system (150) as claimed in one of the preceding claims 1-6 mounted on each spinning unit to carry out a piecing operation when a yarn breakage occurs; and
a yarn monitoring device to detect the breakage of yarn (114) and send a signal to a controller of the spinning machine (100).
8. A method of piecing in a spinning machine (100), the method comprising steps of:
detecting, by a yarn monitoring device of the spinning machine (100), a yarn breakage on a spinning station (102);
pausing spinning operation, of the spinning station (102) with yarn breakage;
pivoting the suction arm (104) towards a package, from a first position or home position (S1) to a second position (S2) to pick up the broken yarn end by a suction mouth (106) of the suction arm (104) upon receiving the signal from the yarn monitoring device;
pivoting the suction arm (104) to a third position (S3) along with the yarn end;
actuating an actuator (118) to pivot an intermediate yarn guide (108) forward from a home position (Y1) to next position (Y2) while the suction arm (104) pivots from the second position (S2) to the third position (S3) to receive the yarn (114) from the suction arm (104);
actuating the actuator (118) to pivot the intermediate yarn guide (108) to pivot backward to the home position (Y1) once the yarn (114) is received from the suction arm (104), thereby forming a loop (120) of yarn (114) between the intermediate yarn guide (108) and suction arm (104);
pivoting the suction arm (104) to the first position from the third position (S3) once the intermediate yarn guide (108) is pivoted to the home position (Y1), thereby transferring the loop (120) of yarn (114) to a hook element (110) of the suction arm (104);
actuating the actuator (118) to pivot the intermediate yarn guide (108) to the next position (Y2);
pivoting the suction arm (104) to a fourth position (S4) thereby releasing the loop (120) formed between the suction arm (104) and intermediate yarn guide (108);
cutting, by a scissor of the suction arm (104) additional yarn (114) between the suction arm (104) and package;
pulling yarn end into spinning unit (103) by suction around the spinning unit (103) and resuming the spinning operation of the spinning station (102); and
pivoting the suction arm (104) to the first position once the spinning operation resumes.