DESC:
FIELD OF THE INVENTION
The present invention relates to drafting roller arrangements in textile machines. More specifically, the invention pertains to a bearing assembly of drafting roller arrangements used in textile spinning preparatory machines such as carding machines, draw frames, combers, lap formers, and spinning machines like roving frames, ring frames, and air jet spinning machines. The invention aims to enhance the durability and efficiency of the bearing assembly in these machines, thereby improving the overall quality and productivity of the textile spinning process.

BACKGROUND OF THE INVENTION
Textile spinning machines such as carding machines, draw frames, combers, lap formers, speed frames, ring frames, and air jet spinning machines include a drafting unit. Drafting is one of the most important processes involved in textile spinning machines. The drafting unit comprises a plurality of drafting rollers, which include upper drafting rollers and lower drafting rollers arranged in a parallel manner. In the drafting unit, the drafting rollers run at different speeds from the back to front roller pairs. During this action, the weight per unit length of fibers is reduced successively so that the fiber assembly becomes thinner. Additionally, some of the fibers in the cross-section of the final fiber strand become straight and parallel.

In the drafting arrangement, top rollers are used to draft the feed slivers by the action of friction as they are loaded against the bottom rollers. Top rollers are covered by a cot made of synthetic rubber or polymer material. Cots in the drafting unit provide uniform pressure applied on the fiber strand. This cot covering influences efficient drafting, resulting in a better grip and control over the fibers, particularly on floating fibers.

However, during continuous operation, the rubber cot mounted on the top roller loses its desired properties, such as shore hardness, and results in honeydew layer formation. This loss in shore hardness is a significant property of the top roller cot that influences drafting quality. Due to these losses, a certain degree of eccentricity develops on the rubber cot, leading to quality deterioration in processing the fiber bundle. Prolonged use causes the cot surface to become smoother progressively, increasing the chances of material slippage and resulting in drafting faults and roller lapping. To improve these cot properties, the cots are ground periodically to enhance sliver quality.

In the existing grinding process of the rubber cots, the bearing unit fixed in the roller shaft must be removed along with the end plug to clamp the top roller between the grinding centers of the grinding machine. In mill practice, due to continuous running and heat generation on top rollers, cot grinding is necessary every 168 hours to improve shore hardness and surface roughness. Due to periodic grinding and improper mounting and dismounting practices of bearings in the top roller shaft, the balls/rollers of the bearing get damaged, affecting the bearing's performance and leading to excessive heat generation and lubricant starvation. This process consumes more effort and time of the personnel involved due to the complexity of the arrangement. Moreover, it affects the operating life of the bearing, shaft, and the durability of the top roller.

In another existing drafting assembly, the bearing assembly is mounted on the extended drafting roller shaft directly. Since the drafting roller shaft is extended throughout the length of the drafting roller, manufacturing the roller is difficult, and the manufacturing cost and time for assembling are higher. In the existing construction, the bearing assembly is exposed to dust and fiber accumulation during normal working processes or grinding processes.

There has thus been a need to enhance the lifetime of the top roller bearing and shaft for drafting rollers for high production with desirable quality that would overcome the disadvantages present in the existing machines.

The present invention provides a technical solution to these problems by introducing a drafting roller arrangement that includes an inner roller shaft, an outer body made of synthetic polymers, and a bearing assembly with a bearing shaft and bearing housing. The bearing shaft is press-fitted against the inner roller shaft, and the bearing assembly is arranged on both sides of the inner roller shaft. The inner roller shaft includes a dust prevention lip to prevent dust accumulation in the bearing during normal operation, thereby enhancing the durability of the bearing assembly. An outer cover is removably coupled with the bearing assembly, ensuring ease of maintenance and protection against dust. An air release hole is provided in the inner roller shaft to avoid trapping air in the chamber during press fitting of the bearing shaft, ensuring proper fitting and operational efficiency.

The inventors have found that by implementing these features, the drafting roller arrangement simplifies the grinding process, reduces wear and tear on the bearing assembly, facilitates precise and efficient grinding, and ensures the bearing assembly can withstand heavy radial loads and high temperatures. Additionally, the design allows for the rubber cot to be replaced without removing the bearing assembly, reducing maintenance time and costs. The raised lip arrangement on the inner roller shaft provides additional heat dissipation during operation, preventing overheating and extending the operational life of the bearing assembly.

OBJECT OF THE INVENTION
The main objective of the present invention is to provide a top roller bearing arrangement that simplifies the process of grinding the roller cot without disturbing the bearing assembly present in the drafting arrangement.

Another objective of the present invention is to provide a top roller bearing arrangement that prevents dust accumulation in the bearing assembly of the roller, thereby enhancing the durability and operational efficiency of the bearing and shaft.

Another objective of the present invention is to increase the durability of the bearing and shaft present in the drafting arrangement of textile spinning preparatory machines, ensuring high production with desirable quality.

Yet another objective of the present invention is to minimize the frequent replacement of the bearing and shaft from the top roller, thereby improving the quality of sliver processed in textile spinning preparatory machines.

One more objective of the present invention is to provide a top roller bearing arrangement that is easy to manufacture, reducing manufacturing costs and assembly time.

SUMMARY OF THE INVENTION
The summary of the invention provided herein is intended to offer an overview of the key features and advantages of the invention. It is not intended to limit the scope of the invention. Various modifications, changes, and variations can be made without departing from the scope and spirit of the invention as defined by the appended claims. The detailed description and figures are to be considered as illustrative and not restrictive, and the invention is not limited to the specific details and configurations shown and described. The scope of the invention is defined by the claims and their equivalents.

According to one aspect of the present invention there is provided a drafting roller arrangement for textile spinning preparatory machines, comprising:
an inner roller shaft;
an outer body;
a bearing assembly with a bearing shaft and a bearing housing; said bearing assembly arranged on both sides of the inner roller shaft; and
-an outer cover removably coupled with the bearing assembly, ensuring ease of maintenance and protection against dust;
wherein an air release hole is provided in the inner roller shaft to avoid trapping of air in the chamber during press fitting of the bearing shaft in the inner roller shaft, thereby ensuring proper fitting and operational efficiency; and at least a raised lip arrangement provided on the inner roller shaft to prevent dust entry and accumulation inside the said bearing assembly.

The drafting roller arrangement for textile spinning preparatory machines comprises an inner roller shaft/arbour; an outer body made of synthetic polymers; a bearing assembly with bearing shaft and bearing housing; wherein the bearing shaft is press-fitted against the inner roller shaft. The bearing assembly is arranged on both side of said inner roller shaft, which consists of bearing shaft; wherein the bearing shaft and the inner roller arbour are connected by means of an interference fit. The inner roller shaft consists of a dust preventing lip for prevention of dust accumulation in the bearing during normal running. An outer cover cap is provided in said bearing assembly. The outer covers are removably coupled with the bearing assembly by a fastening means. An air release hole is made in the inner roller shaft, which aids in avoiding trapping of air in the chamber during press fitting the bearing shaft in the inner roller shaft.

While cot grinding, only the outer cover is detached from the top roller assembly which ensures the top roller and bearing is not separated whereas the other side of the bearing shaft is used for holding the roller during grinding process. In this condition, the top roller assembly together with the bearing assembly will be fixed in the grinding machine for grinding process. The grinding center hole is available on both end portions of the bearing shaft. The Bearing in the top roller is clamped by a spring loading arrangement whose load is predetermined and fixed which cannot be varied by the user.

In another embodiment, the outer diameter/layer of the bearing with or without end bush arrangement can be made lesser than the inner diameter of the cot that is mounted on the top roller shaft. This eliminates the need for dismantling the bearing with end bush arrangement even during replacement of new cot when the existing cot reached the end of its life due to grinding or any other reason. i.e., Only the rubber cot can be replaced without removing bearing assembly

In further embodiment, the bearing in the top roller may also be clamped by an axial clamping arrangement or radial clamping arrangement with interference fit. As a result, bearing will remain undisturbed and practical life of the bearing and shaft will be ensured same as that of the predetermined one. The roller arbor has a raised lip arrangement which prevents the accumulation of dust/lints in the bearing housing during operation condition.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The above and other aspects, features and advantages of the embodiments of the present disclosure will be more apparent in the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates the top roller and bearing arrangement according to the present invention, showing the roller assembly (1) and the bearing assembly (4) positioned on both sides of the roller assembly.

FIG. 2 provides an enlarged view of a section of the drafting roller with the connector assembly, according to the present invention. It shows the inner roller shaft (2), the outer body (3), the dust prevention lip (7), the bearing housing (5), the bearing shaft (6), and the outer cover (8).

FIG. 3 illustrates the top roller bearing arrangement and the housing of the connector assembly arranged in a grinding center according to the present invention. It shows the outer body (3), the inner roller shaft (2), the bearing housing (5), the bearing shaft (6), the dust prevention lip (7), and the grinding machine center (9).

The accompanying drawings illustrate various embodiments of the present invention and are provided for the purpose of explaining the principles of the invention. These drawings are not intended to limit the scope of the invention. The components and arrangements shown in the drawings may be modified or substituted with equivalent elements to achieve the same or similar results. The invention is not limited to the specific details and configurations shown and described in the drawings.

DETAILED DESCRIPTION OF THE INVENTION
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in that understanding, but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the various embodiments described herein can be made without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and constructions may be omitted for clarity and conciseness.

All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which various embodiments belong. Further, the meaning of terms or words used in the specification and the claims should not be limited to the literal or commonly employed sense but should be construed in accordance with the spirit of the disclosure to most properly describe the present disclosure.

The terminology used herein is for the purpose of describing particular various embodiments only and is not intended to be limiting of various embodiments. As used herein, the singular forms "a," "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising" used herein specify the presence of stated features, integers, steps, operations, members, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, members, components, and/or groups thereof.

The present disclosure will now be described more fully with reference to the accompanying drawings, in which various embodiments of the present disclosure are shown.

DEFINITION OF TECHNICAL TERMS:
Roller Assembly (1): The component of the drafting roller arrangement that includes the inner roller shaft and the outer body. It provides structural support and facilitates the attachment of other components.

Bearing Assembly (4): A component that includes the bearing shaft and bearing housing. It supports the roller assembly and allows it to rotate smoothly while withstanding radial loads and high temperatures.

Inner Roller Shaft (2): A central shaft within the roller assembly that provides structural support and facilitates the attachment of the bearing assembly. It includes features such as the dust prevention lip and air release hole.

Outer Body (3): The external part of the roller assembly made of synthetic polymers. It provides a surface for the roller to interact with the fibers during the drafting process.

Dust Prevention Lip (7): A raised lip on the inner roller shaft that prevents dust from entering and accumulating inside the bearing assembly, thereby enhancing the durability and operational efficiency of the bearing assembly.

Bearing Housing (5): The casing that encases the bearing components, providing protection and support. It is part of the bearing assembly.

Bearing Shaft (6): A shaft within the bearing assembly that is press-fitted against the inner roller shaft. It supports the bearing components and allows the roller assembly to rotate smoothly.

Outer Cover (8): A removable cover that is coupled with the bearing assembly by a fastening means. It provides protection against dust and facilitates easy maintenance by allowing access to the bearing assembly without disassembly.

Grinding Machine Center (9): The part of the grinding machine where the roller assembly is held during the cot grinding process. It interacts with the grinding center holes on the bearing shaft to facilitate precise and efficient grinding.

The present invention provides a drafting roller arrangement for textile spinning preparatory machines, designed to enhance the durability and efficiency of the bearing assembly and simplify maintenance processes. The invention includes the following detailed aspects:

Referring to FIG. 1, the drafting roller arrangement comprises a roller assembly (1) and a bearing assembly (4). The roller assembly (1) includes an inner roller shaft (2) and an outer body (3) made of synthetic polymers. The inner roller shaft (2) provides structural support and facilitates the attachment of the bearing assembly (4) on both sides of the roller assembly (1). Several types of synthetic polymers can be used in the outer body (3) of the roller assembly, each offering specific advantages:

Polyurethane (PU): Known for its excellent abrasion resistance and flexibility, polyurethane is ideal for components that require a high level of durability and grip.

Polyethylene (PE): Polyethylene offers good chemical resistance and is lightweight, making it suitable for applications where weight reduction is important.

Polyamide (Nylon): Nylon is known for its strength and toughness, providing a robust solution for components subjected to high stress and friction.

Polypropylene (PP): Polypropylene is resistant to chemicals and has a low density, making it a cost-effective and lightweight option for the outer body.

As shown in FIG. 2, the inner roller shaft (2) further consists of a raised lip arrangement (7) which prevents dust entry and accumulation inside the bearing assembly (4). This feature enhances the durability and operational efficiency of the bearing assembly. The bearing assembly (4) consists of a bearing housing (5) with a lifetime grease bearing unit and a bearing shaft (6). The lifetime grease bearing unit comprises a ball cum roller bearing, a ball cum needle bearing, or a roller cum needle bearing, making the bearing suitable to withstand heavy radial loads and high temperatures. The bearing shaft (6) is provided with two longitudinal ends at each extreme point, wherein one end of the bearing shaft (6) is press-fit against the inner roller shaft (2). The other end of the bearing shaft (6) is provided with grinding center holes near to which the bearing assembly (4) is mounted. An air release hole (10) is provided in the inner roller shaft (2) to avoid air trapping in the chamber while press fitting the bearing shaft (6) to the inner roller shaft (2). Further, an outer cover (8) is provided over the bearing assembly (4) to cover the bearing assembly. A suitable fastening means is provided to assemble the outer cover (8) over the bearing assembly (4), so that the outer cover (8) will not come off while the machine is in running condition. The fastening means may be a screw or tap coupling which interconnects the bearing assembly (4) and outer cover (8).

During normal running conditions, the drafting roller arrangement is placed on the drawing unit of the draw frame machine. As illustrated in FIG. 3, when there is a need for the cot grinding process, only the outer cover (8) has to be detached from the top roller assembly, ensuring the bearing shaft (6) ends are accessible from the longitudinal direction. However, the top roller assembly (1) and bearing assembly (4) are not separated from the arrangement. Hence, the extreme sides of the bearing shaft (6) can be used for holding the roller in a grinding machine center (9). Thus, the top roller assembly together with the bearing assembly (4) will be fixed in the grinding machine for grinding purposes. The grinding center hole is available at both end portions of the bearing shaft (6). After the grinding process, the bearing assembly (4) is covered again using the outer cover (8) and is placed in the drafting unit of the draw frame machine.

In another embodiment, the outer diameter of the bearing assembly (4) with or without an end bush arrangement is made lesser than the inner diameter of the cot mounted on the top roller shaft. This design allows the rubber cot to be replaced without removing the bearing assembly (4), reducing maintenance time and costs.

In a further embodiment, the bearing assembly (4) is clamped by an axial clamping arrangement or a radial clamping arrangement with interference fit. This ensures the bearing remains undisturbed during operation, enhancing its practical life.

The raised lip arrangement (7) on the inner roller shaft (2) provides additional heat dissipation during operation, preventing overheating and extending the operational life of the bearing assembly.

The present invention thus addresses the technical problems and disadvantages of prior art by providing a robust and efficient drafting roller arrangement that enhances the durability of the bearing assembly, simplifies maintenance processes, and ensures high-quality sliver production in textile spinning preparatory machines.

Some non-limited advantages of the present invention:

1. Enhanced Durability: The inclusion of a dust prevention lip (7) on the inner roller shaft (2) prevents dust accumulation inside the bearing assembly (4), thereby enhancing the durability and operational efficiency of the bearing assembly. This feature ensures a longer lifespan for the bearing and shaft components.

2. Simplified Maintenance: The outer cover (8) is removably coupled with the bearing assembly (4) by a fastening means, allowing easy access to the bearing assembly without disassembly. Said fastening means may be a screw or tap coupling which interconnects the bearing assembly (4) and outer cover (8). This simplifies maintenance processes and reduces downtime.

3. Efficient Cot Grinding: During the cot grinding process, only the outer cover (8) needs to be detached from the top roller assembly, ensuring that the top roller and bearing assembly (4) are not separated. The bearing shaft (6) is provided with grinding center holes at both end portions, facilitating precise and efficient grinding. This design reduces wear and tear on the bearing assembly and simplifies the grinding process.

4. High Load and Temperature Resistance: The bearing assembly (4) comprises a lifetime grease bearing unit, which includes a ball cum roller bearing, a ball cum needle bearing, or a roller cum needle bearing. This ensures the bearing assembly can withstand heavy radial loads and high temperatures, enhancing its operational lifespan.

5. Reduced Maintenance Time and Costs: The outer diameter of the bearing assembly (4) with or without an end bush arrangement is made lesser than the inner diameter of the cot mounted on the top roller shaft. This allows the rubber cot to be replaced without removing the bearing assembly (4), reducing maintenance time and costs.

6. Stable Clamping Arrangements: The bearing assembly (4) is clamped by an axial clamping arrangement or a radial clamping arrangement with interference fit. This ensures the bearing remains undisturbed during operation, enhancing its practical life.

7. Improved Heat Dissipation: The raised lip arrangement (7) on the inner roller shaft (2) provides additional heat dissipation during operation, preventing overheating and extending the operational life of the bearing assembly.

8. Operational Efficiency: The air release hole (10) in the inner roller shaft (2) avoids trapping air in the chamber during press fitting of the bearing shaft (6), ensuring proper fitting and operational efficiency.

The present invention thus addresses the technical problems and disadvantages of prior art by providing a robust and efficient drafting roller arrangement that enhances the durability of the bearing assembly, simplifies maintenance processes, and ensures high-quality sliver production in textile spinning preparatory machines.

The present invention provides a robust and efficient drafting roller arrangement for textile spinning preparatory machines. However, there are several future enhancements and possibilities within the scope and spirits of the present invention that can further improve the performance and functionality of the invention:

1. Advanced Materials: Future enhancements could include the use of advanced materials for the inner roller shaft (2) and outer body (3), such as high-performance polymers or composite materials. These materials could offer improved strength, durability, and resistance to wear and tear, further extending the lifespan of the drafting roller arrangement.

2. Smart Sensors: Integrating smart sensors into the bearing assembly (4) could provide real-time monitoring of the bearing's condition, including temperature, vibration, and load. This data could be used to predict maintenance needs, prevent unexpected failures, and optimize the performance of the drafting roller arrangement.

3. Automated Maintenance: Future developments could include automated maintenance systems that can perform tasks such as cot grinding and bearing lubrication without manual intervention. This would further reduce downtime and maintenance costs while ensuring consistent performance.

4. Enhanced Dust Prevention: While the current design includes a dust prevention lip (7), future enhancements could explore additional dust prevention mechanisms, such as advanced sealing technologies or self-cleaning surfaces, to further protect the bearing assembly (4) from dust and debris.

5. Modular Design: Developing a modular design for the drafting roller arrangement could allow for easy replacement of individual components, such as the inner roller shaft (2), outer body (3), or bearing assembly (4). This would simplify repairs and upgrades, reducing downtime and extending the overall lifespan of the machine.

6. Energy Efficiency: Future enhancements could focus on improving the energy efficiency of the drafting roller arrangement. This could include optimizing the design to reduce friction and energy consumption or incorporating energy recovery systems to capture and reuse energy generated during operation.

7. Customization Options: Offering customization options for the drafting roller arrangement could allow manufacturers to tailor the design to specific applications or materials. This could include adjustable clamping arrangements, variable cot hardness, or different bearing configurations to optimize performance for different types of fibers or production processes.

8. Integration with Industry 4.0: Future developments could include integrating the drafting roller arrangement with Industry 4.0 technologies, such as IoT (Internet of Things) and data analytics. This would enable real-time monitoring, predictive maintenance, and data-driven optimization of the entire textile spinning process.

9. Environmental Sustainability: Future enhancements could focus on improving the environmental sustainability of the drafting roller arrangement. This could include using eco-friendly materials, reducing energy consumption, and implementing recycling programs for worn-out components.

10. User-Friendly Interfaces: Developing user-friendly interfaces for monitoring and controlling the drafting roller arrangement could improve ease of use and accessibility. This could include touchscreen displays, mobile apps, or remote monitoring systems that provide real-time data and alerts to operators.

By exploring these future enhancements and possibilities, the drafting roller arrangement can continue to evolve and meet the changing needs of the textile industry, ensuring high-quality sliver production and efficient operation for years to come.

The embodiments of the present invention described herein are intended to provide a comprehensive understanding of the invention. However, it should be understood that the invention is not limited to the specific embodiments disclosed. Various modifications, changes, and variations can be made without departing from the scope and spirit of the invention as defined by the appended claims.

The figures provided are for illustrative purposes only and are not intended to limit the scope of the invention. The components and arrangements shown in the figures may be modified or substituted with equivalent elements to achieve the same or similar results.

The present invention is intended to cover all changes, modifications, and variations within the meaning and range of equivalency of the claims. It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.

The scope of the invention is defined by the claims and their equivalents. The detailed description and figures are to be considered as illustrative and not restrictive, and the invention is not limited to the specific details and configurations shown and described.
,CLAIMS:
1. A drafting roller arrangement for textile spinning preparatory machines, comprising:
an inner roller shaft (2);
an outer body (3);
a bearing assembly (4) with a bearing shaft (6) and a bearing housing (5); said bearing assembly (4) arranged on both sides of the inner roller shaft (2);
an outer cover (8) removably coupled with the bearing assembly (4);
wherein an air release hole (10) is provided in the inner roller shaft (2) to avoid trapping of air in the chamber during press fitting of the bearing shaft (6) in the inner roller shaft (2), thereby ensuring proper fitting and operational efficiency; and
at least a raised lip arrangement (7) provided on the inner roller shaft (2) to prevent dust entry and accumulation inside the said bearing assembly (4).

2. The drafting roller arrangement as claimed in claim 1, wherein the outer cover (8) is detached from the top roller assembly during cot grinding, ensuring that the top roller and bearing assembly (4) are not separated, thereby simplifying the grinding process and reducing wear and tear on the bearing assembly (4).

3. The drafting roller arrangement as claimed in claim 1, wherein the bearing shaft (6) is provided with grinding center holes at both end portions for holding the roller during the grinding process, thereby facilitating precise and efficient grinding.

4. The drafting roller arrangement as claimed in claim 1, wherein the bearing assembly (4) comprises a lifetime grease bearing unit, which includes a ball cum roller bearing, a ball cum needle bearing, or a roller cum needle bearing, thereby ensuring the bearing assembly (4) can withstand heavy radial loads and high temperatures, enhancing its operational lifespan.

5. The drafting roller arrangement as claimed in claim 1, wherein the outer diameter of the bearing assembly (4) with or without an end bush arrangement is made lesser than the inner diameter of the cot mounted on the top roller shaft, allowing the rubber cot to be replaced without removing the bearing assembly (4), thereby reducing maintenance time and costs.

6. The drafting roller arrangement as claimed in claim 1, wherein the bearing assembly (4) is clamped by an axial clamping arrangement, or a radial clamping arrangement with interference fit, thereby ensuring the bearing remains undisturbed during operation, enhancing its practical life.

7. The drafting roller arrangement as claimed in claim 1, wherein the raised lip arrangement (7) on the inner roller shaft (2) provides additional heat dissipation during operation, thereby preventing overheating and extending the operational life of the bearing assembly (4).

8. The drafting roller arrangement as claimed in claim 1, wherein the outer body (3) is made of synthetic polymers.

9. The drafting roller arrangement as claimed in claim 1, wherein the bearing shaft (6) is press-fitted against the inner roller shaft (2).