DESC:
FIELD OF THE INVENTION
The present invention relates to the field of textile machinery, specifically to yarn spinning units used in textile spinning machines. More particularly, the invention pertains to an improved yarn spinning nozzle design for air jet spinning machines, which enhances the efficiency and quality of yarn production by optimizing the airflow dynamics within the spinning unit.

Application of the Invention
The invention is applicable in the textile industry, particularly in facilities utilizing air jet spinning machines for yarn production. The improved nozzle design can be integrated into existing spinning units to increase production rates and improve yarn quality. By optimizing the airflow and twist insertion process, the invention addresses common issues such as insufficient fiber wrapping and yarn hairiness, making it suitable for high-speed spinning operations while maintaining stringent quality. This invention is beneficial for textile manufacturers seeking to enhance productivity and product quality in competitive markets.

BACKGROUND OF THE INVENTION
The textile spinning machines are used to convert the fibrous raw material into spun yarn through various processes. More number of machineries works continuously in the textile spinning mill for higher yarn production rate. At the end of each stage of spinning processes, various end products are produced such as fibre tuft, lap, web, roving yarn and like.

In the air jet spinning machines, the sliver material delivered from the preceding draw frame machine is taken as a feed material. The three main actions take place in the air-jet process are feeding, twisting and winding. A high-speed airflow gets used to insert twist into the yarn in the air-jet spinning system. The twist insertion system is composed of an air-jet nozzle and a hollow spindle in which a yarn passes through. The nozzle present in the spinning unit is responsible for conversion of fibres into yarn by virtue of compressed air stream passed through the nozzle.

The nozzle present in the spinning unit is applied to produce swirling air flow that acts on the fibre bundle and there upon giving a false twist to make the yarn in the air jet spinning machine. The whirling of air causes the wrapping fibers to wound around the Core fiber. The Nozzle block has a fibre feed hole by which the fiber bundle passes at the centre. Plurality of air injection holes provided in the nozzle unit and said injection holes faces substantially tangential direction to fibre feed hole in order to apply a twisting force onto the fiber bundle passing through the whirling chamber. The air stream ejected from the nozzle outlet forms a swirling flow in the through hole and acts on the fiber bundle to wrap the outer fibers over the core fibers of the said bundle.

In the conventional air jet spinning machines, the profile of the air jet hole in the nozzle unit is straight and the diameter of the said air jet hole is configured to be identical at the inlet and outlet point. In this configuration, the yarn production rate is low. To increase the production rate, the spinning speed has to be increased. In order to increase the spinning speed, the linear speed or travelling speed of the running yarn must be matched to the spinning velocity which results in inferior quality in the final yarn.

The quality differences in the yarn is due to insufficient wrapping of outer fibre around the core fibre and more protruding fibre in the outer surface of the yarn. Therefore, increasing the spinning speed to achieve high production rate, results in more variations in the hairiness index as well in the resultant yarn.

To overcome the above disadvantages, the present invention provides a rounded and seamless change in the nozzle profile transition, which aids in increasing the spinning speed while maintaining the necessary quality standards of yarn.

OBJECTS OF THE INVENTION
The main objective of the invention is to provide an improved nozzle profile for the air jet spinning machines.

Another object of the invention is to provide an improved nozzle profile which helps in achieving the higher production rate by increasing the spinning speed.

One more object of the invention is to provide an improved nozzle profile with tapered cross section in the air flow path which helps for accelerating the spinning speed without affecting the quality standards of yarn.

SUMMARY OF THE INVENTION
The present invention provides an improved nozzle profile for the air jet spinning machines. According to the invention, the air jet spinning machine comprises plurality of spinning stations each of which provided with at least a yarn spinning device; said yarn spinning device further comprises a nozzle block configured to have plurality of air injection nozzles; each air injection nozzles composed of a curved profile, wherein the said curved profile forms a path for compressed air flow and wherein the entry point and exit point of said path is configured to have different diameter. Since there is a rounded profile transition in the air flow path of the nozzle, the pressure flow and spinning velocity inside the nozzle get increased. This helps in increasing the spinning speed without affecting the yarn properties.

Nozzle block of the said spinning device is an essential part of the air spinning machine that receives fiber bundle from the drafting device and uses plurality of air jet injection nozzles to create a swirling airflow for imparting twist onto the said fiber bundles. The whole arrangement of the spinning device comprises at least a hollow spindle having an opening for the fiber bundle opened at the tip; a guide member extending in the nozzle block toward the spindle's passage; and the yarn is produced between the nozzle block and the spindle by means of swirling airflow in the whirling chamber. Said spinning device consists of a hollow chamber to be discharged; a casing that supports the nozzle block and the spindle and has a space for discharging air from the hollow chamber; the spinning device from the hollow chamber to the space. The air jet yarn formed in the spinning device is then delivered out of the spinning unit through the delivery rollers and fed to the winding unit.

The air injection hole according to the aspect of the invention is configured as a fine hole having a small diameter in order to obtain an appropriate air flow rate. Thus, the spinning nozzle helps in inserting false twist to the yarn which drafted from the drafting device in the air jet spinning machines.

According to further aspect of the invention, the diameter of the air exit at inner surface of the nozzle is nearly 0.6mm, which progressively decreasing from around 0.9mm at the air entering/inlet section of the nozzle. Viewed from vertical axis, the exit point of the injection nozzle is provided on the lower side when compared to the air entry point/inlet point. This provides a rounded and seamless change in profile transition, thereby gradually increase the pressure flow and maintain a uniform spinning velocity inside the nozzle path. The diameter difference in the nozzle between the entry and exit points prevents insufficient wrapping of the outer fiber around the core fiber and thus avoids protruding fibers in the yarn's outer diameter. Therefore, the variations arise in the yarn hairiness index is reduced and improved the quality requirements of the air spun yarn.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 shows the cross sectional view of the nozzle of the air-jet spinning machine according to the present invention

Figure 2 shows the nozzle profile of the air jet spinning machine according to the present invention.

Figure 3 shows the variations in the dimensions of the nozzle of the air jet spinning machine according to the present invention.

The figures depict embodiment of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiment of the mechanism illustrated herein may be employed without departing from the principles of the disclosure description herein.

DETAILED DESCRIPTION OF THE INVENTION
The air jet spinning device (1) described in the present invention is a sophisticated apparatus designed to enhance the efficiency and quality of yarn production in textile machines. This device features a nozzle block arrangement (2), as illustrated in Figures 1, 2, and 3, which plays a crucial role in the spinning process.

The process begins with fibers being delivered from a drafting unit (not shown in the figures) into the feeding zone (6) of the spinning device (1). The drafting unit is responsible for aligning and thinning the fibers to prepare them for spinning. As the fibers enter the feeding zone (6), they are positioned for the subsequent twisting process.

Simultaneously, a stream of compressed air is directed through the air injection nozzles (3) into the whirling chamber (5). The air injection nozzles (3) are strategically designed to create a swirling airflow within the whirling chamber (5). This swirling motion is essential for imparting a twist onto the fibers, which is a critical step in transforming them into yarn.

Adjacent to the feeding zone (6), the device includes at least one spindle element (4). The spindle element (4) is integral to the twisting process, as it assists in imparting a false twist onto the fibers. A false twist is a temporary twist applied to the fibers to stabilize and align them during the spinning process. This twist is crucial for ensuring that the fibers are properly wrapped and bound together to form a cohesive yarn structure.

The air injected from the plurality of nozzles (3) in the nozzle block (2) follows a circular path, which is instrumental in the twisting process. The circular motion of the air stream helps to wrap the outer fibers around the core fibers, creating a stable and uniform yarn. This swirling airflow is facilitated by the tapered profile of the air injection nozzles (3), which ensures that the air maintains its velocity and pressure as it enters the whirling chamber (5).

The tapered profile of the nozzles is designed to optimize the depth and intensity of the swirling airflow within the whirling chamber (5). By minimizing the depth of the air path, the design ensures that the air swirls efficiently, maximizing the twisting effect on the fibers. This efficient swirling action is crucial for achieving a high-quality yarn with minimal defects such as hairiness or unevenness.

Overall, the air jet spinning device (1) leverages the innovative design of the nozzle block arrangement (2) and the strategic use of swirling airflow to enhance the yarn production process. The integration of the feeding zone (6), spindle element (4), and whirling chamber (5) ensures that fibers are effectively transformed into high-quality yarn, meeting the demands of modern textile manufacturing.

Referring to Figure 2, the air injection nozzles (3) within the nozzle block arrangement (2) are depicted with a distinctive curved profile. This design is integral to the functionality of the air jet spinning device, as it directly influences the efficiency and quality of the yarn production process.

The curved profile of the air injection nozzles (3) is engineered to create a converged path for the compressed air flow. This convergence is crucial as it focuses the air stream, increasing its velocity and pressure as it moves through the nozzle block arrangement (2). The focused air stream is essential for the effective transportation and manipulation of fibers during the spinning process.

As fibers are introduced into the spinning device, they are smoothly guided into the spindle element (4), as shown in Figure 1. The smooth transportation of fibers is facilitated by the converged air path, which minimizes turbulence and ensures a consistent flow. This consistency is vital for maintaining the alignment and integrity of the fibers as they progress through the spinning stages.

The compressed air, blown from the air injection nozzles (3), interacts with the outer surface of the spindle element (4) at its inlet. This interaction initiates the twisting process of the outer wrapping fibers. The high-speed air stream imparts a false twist to the fibers, which is a temporary twist that aids in the stabilization and cohesion of the fiber bundle as it is transformed into yarn.

A notable feature of the invention is the tangential opening of the air intake holes around the circumference of the inner nozzle surface. This tangential configuration is designed to enhance the wrapping of outer fibers around the core fibers. By directing the air flow tangentially, the design ensures that the fibers are subjected to a consistent twisting force, which is crucial for achieving a uniform and tightly wrapped yarn structure.

Additionally, the nozzles are designed with a tapered portion at the entry on both the outer periphery and the inner surface. This tapering helps to further refine the air flow, reducing the likelihood of insufficient wrapping of the outer fibers around the core fibers. The tapering ensures that the air stream maintains its velocity and pressure as it enters the whirling chamber (5).

Within the whirling chamber (5), the twisting of fibers is completed. The chamber provides a controlled environment where the fibers are subjected to the swirling air flow, which finalizes the twist imparted by the air injection nozzles (3). Once the fibers are adequately twisted, the resulting yarn is passed through the yarn flow channel in the spindle element (4). This channel guides the twisted yarn out of the spinning device, ready for further processing or winding.

Overall, the design of the air injection nozzles (3) and their integration into the nozzle block arrangement (2) play a pivotal role in enhancing the efficiency and quality of the yarn spinning process. The curved profile, tangential air intake, and tapered entry collectively contribute to a more effective and reliable spinning operation.

In Figure 3, the nozzle arrangement of the air jet spinning device is depicted with a specific focus on the design of the air injection nozzle (3). This design is a key aspect of the present invention, aimed at optimizing the airflow dynamics within the spinning unit to enhance yarn production efficiency and quality.

According to this preferred embodiment, the air injection nozzle (3) is characterized by a profile that varies between the entry and exit points. This variation is achieved through a tapered cross-section and a curved contour along the air flow path. The tapering of the nozzle is a deliberate design choice that serves to gradually reduce the diameter of the air path from the entry to the exit point. Specifically, the diameter at the air entry point is approximately 0.9mm, while the diameter at the air exit point is reduced to about 0.6mm. This progressive decrease in diameter is crucial for controlling the velocity and pressure of the air stream as it moves through the nozzle.

The curved contour of the nozzle further enhances the efficiency of the airflow. By shaping the air path in a curved manner, the design ensures that the air stream follows a smooth trajectory, minimizing turbulence and energy loss. This smooth flow is essential for maintaining a consistent and high-speed air stream, which is necessary for the effective twisting of fibers in the spinning process.

When viewed from a vertical axis, the exit point of the air injection nozzle is positioned lower than the entry point. This vertical offset is another strategic design element that contributes to the overall functionality of the nozzle. By positioning the exit point lower, the design facilitates a natural acceleration of the air stream as it moves downward, leveraging gravity to assist in maintaining a high velocity.

The combination of the tapered cross-section, curved contour, and vertical offset provides a mechanism for adjusting the velocity of the air flow while keeping the pressure constant. This capability is particularly beneficial in the context of yarn spinning, where maintaining a consistent pressure is vital for ensuring uniform yarn quality. By allowing for changes in air velocity without altering pressure, the nozzle design supports increased spinning speeds, which in turn leads to higher production rates.
Importantly, this design innovation does not compromise the quality standards of the yarn. The controlled and efficient airflow ensures that fibers are properly twisted and wrapped, reducing defects such as hairiness and unevenness in the yarn. As a result, the invention not only boosts production efficiency but also upholds the high-quality standards expected in textile manufacturing.

ADVANTAGES OF THE PRESENT INVENTION
The present invention offers several advantages over conventional air jet spinning nozzles:

1. Increased Production Rate: The improved nozzle design allows for higher spinning speeds, thereby increasing the overall production rate without compromising yarn quality.

2. Enhanced Yarn Quality: By optimizing the airflow dynamics and twist insertion process, the invention reduces issues such as insufficient fiber wrapping and protruding fibers, resulting in a smoother yarn with a lower hairiness index.

3. Improved Airflow Efficiency: The curved profile and tapered cross-section of the air injection nozzles enhance the pressure flow and spinning velocity, leading to more efficient use of compressed air.

4. Seamless Profile Transition: The rounded and seamless change in the nozzle profile transition helps maintain uniform spinning velocity, which is crucial for consistent yarn quality.

5. Reduced Yarn Defects: The design minimizes variations in yarn hairiness and other defects, ensuring that the final product meets high-quality standards.

6. Adaptability to Existing Systems: The nozzle design can be integrated into existing air jet spinning machines, allowing textile manufacturers to upgrade their equipment without significant overhauls.

7. Cost-Effectiveness: By improving the efficiency and quality of yarn production, the invention can lead to cost savings in terms of reduced waste and higher throughput.

8. Versatility: The invention can be applied to various types of fibers and yarns, making it a versatile solution for different textile applications.

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. It is to be understood that the aspects and embodiment of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiment may be combined together to form a further embodiment of the disclosure.
,CLAIMS:
1. An air jet spinning device (1) for textile machines, comprising:
a nozzle block arrangement (2); a whirling chamber (5) configured to impart a false twist onto fibers and a spindle element (4) positioned adjacent to the whirling chamber (5) to assist in the twisting process;
said nozzle block arrangement (2) further comprises a plurality of air injection nozzles (3), each air injection nozzle (3) configured with a curved profile forming a path for compressed air flow, wherein the entry point and exit point of said path have different diameters so as to increase pressure flow and spinning velocity.

2. The air jet spinning device (1) according to claim 1, wherein the diameter of the air exit at the inner surface of the air injection nozzle (3) being approximately 0.6mm and progressively decreasing from around 0.9mm at the air entry point.

3. The air jet spinning device (1) according to claim 1, wherein the air injection nozzles (3) are configured to open tangentially around the circumference of the inner nozzle surface to facilitate the wrapping of outer fibers around core fibers.

4. The air jet spinning device (1) according to claim 1, wherein the air injection nozzles (3) having a tapered cross-section and a curved contour to maintain a uniform spinning velocity inside the nozzle path.

5. The air jet spinning device (1) according to claim 1, wherein the exit point of the air injection nozzle (3) is positioned lower than the entry point when viewed from a vertical axis, providing a seamless change in profile transition.

6. The air jet spinning device (1) according to claim 1, wherein the spinning device (1) is configured to deliver the air jet yarn through delivery rollers to a winding unit.

7. The air jet spinning device (1) according to claim 1, wherein the air injection nozzles (3) are designed to reduce insufficient wrapping of outer fibers around core fibers, thereby minimizing variations in yarn hairiness.

8. The air jet spinning device (1) according to claim 1, wherein the spinning speed is increased by maintaining a constant pressure in the air flow path, achieving a higher production rate while preserving yarn quality standards.

9. The air jet spinning device (1) according to claim 1, wherein the nozzle block arrangement (2) is configured to create a swirling airflow in the whirling chamber (5) to enhance the twisting of fibers.

10. The air jet spinning device (1) according to claim 1, wherein the spindle element (4) includes a yarn flow channel for guiding the twisted yarn out of the whirling chamber (5).