Innovation in the LENO device

Abstract

This invention relates to an innovation made in the leno device, which is used in dobby, jacquard, and air-jet weaving machines. In the leno apparatus introduced in this invention, a discharge opening is positioned at the magnetization point beneath the plastic rod. A flat metal blade moves within the channel to effectively clear out dust, lint, and other debris that gathers under the rod, directing it through this outlet. This innovation successfully removes factors that interfere with magnetization, enabling performance levels significantly even in extreme conditions, at maximum operating speeds, and in heavily contaminated environments.

Description

[0001] DESCRIPTION

[0002] INNOVATION IN THE LENO DEVICE

[0003] TECHNICAL FIELD

[0004] The invention pertains to a novel development in the leno device, which is applicable in dobby, jacquard, and air-jet weaving machines, used to produce stable and secure fabric selvedges.

[0005] BACKGROUND OF THE INVENTION

[0006] Edge Structures in Woven Fabrics:

[0007] Weaving is recognized as one of the oldest crafts in human history. For tens of thousands of years, weavers have produced fabrics with genuine selvedges. However, the production of various selvedge types began only in the last fifty years. Selvedges are a critical factor in determining the quality of a fabric. With the increase in weaving speeds, traditional selvedge quality has been compromised, introducing several issues.

[0008] Ensuring the formation of a stable fabric edge is essential to prevent fraying. Moreover, the fabric’s ability to maintain its shape during weaving and subsequent finishing processes largely depends on its edge construction. In shuttle looms, the selvedge forms naturally, creating what is referred to as a "true selvedge." In contrast, shuttleless looms require additional systems, with four main types of leno selvedge techniques in use. Implementing these systems incurs additional costs .

[0009] Leno Weave:

[0010] Leno fabrics are loosely woven yet structurally stable textiles created through the crossed movement of warp yarns. The formation of leno weave requires a rotary leno device. Conventional Leno Device in the Art:

[0011] To maintain the integrity of the fabric edges during weaving, conventional leno devices utilizing two warp yarns are used on both sides of the fabric. These devices are typically mounted via an apparatus known as the Elsy Steep. Each weaving machine is equipped with two Elsy Steep units — one on each side.

[0012] The conventional leno device derives its motion from the Elsy Steep unit and produces a strong edge by intertwining two warp threads with a weft yarn at the edge. Some devices are also mounted onto the harness frames. A standard leno device consists of two plastic rods and a flat metal leno blade. Some models additionally include a plastic rod guard. Each plastic rod contains two magnets — one on the right and one on the left bottom ends.

[0013] Despite their widespread use, conventional leno devices present several challenges related to edge formation. These devices are used in the following types of weaving machines:

[0014] • Dobby weaving machines

[0015] • Jacquard weaving machines

[0016] • Air-jet weaving machines

[0017] Edge formation techniques in shuttleless looms four common methods are used to create fabric selvedges:

[0018] • Folded Edge

[0019] • Fringed Edge

[0020] • Melted Edge

[0021] • Leno Edge

[0022] The choice among these techniques depends on machine type, raw material properties, and production requirements. Folded Edge: This technique involves tucking the excess weft yarn (approximately 1-1.5 cm) into the next shed, resulting in two weft threads at the selvedge — one newly inserted, and the other from the previous pick. It is universally applicable across all weft types and is supported in rapier and some jet looms. However, due to high speeds in jet looms, folded edges may not suffice. A reduction in mechanical parts is advantageous as it reduces breakdowns and cleaning downtime, thereby increasing loom efficiency.

[0023] Fringed Edge: This method involves cutting the projecting ends of weft yarns with a mechanical cutter. Immediately after weft insertion, edge clamps capture the yarn ends and draw them to the fabric edge. Cutter units placed in front of the clamps trim the yarns evenly. The trimmed yarn is then collected via suction and discarded . This method is known as the "Selvedge Saver."

[0024] Melted Edge: This simple technique uses heat to fuse the outermost warp and weft yarns, suitable only for thermoplastic fabrics. It effectively prevents fraying and is used in wide-width applications. The fused portion is then cut by heated elements (resistors), producing a clean edge. Controlling bead formation due to overheating is crucial, as excessive melting deteriorates appearance and usability.

[0025] Leno Edge: Leno edges are formed by twisting the outermost warp yarns over each other, capturing the weft ends in the process. Additional selvedge warp threads (usually 2-12 high-twist polyester yarns) are introduced to form the leno structure. Leno edge is preferred in high-speed rapier and jet looms, including dobby and jacquard systems.

[0026] Once the leno edge is formed, it is separated from the ground fabric using cutters or resistors. As the separated leno portion is discarded, minimizing yarn waste during edge formation is essential.

[0027] Weft ends may be trimmed either mechanically or via heat, depending on the fiber type. Thermal cutting is particularly suitable for synthetic yarns and provides additional edge sealing benefits. However, this should not be confused with the melted edge method. After trimming, the structure resembles a fringed edge, though the weft is held by twisted warp yarns rather than clamps.

[0028] Leno edges are not as effective as folded edges in preventing warp slippage, but their simpler and cost-effective mechanisms make them widely adopted.

[0029] Approximately 8-13% of warp breakages originate from auxiliary selvedges or conventional leno devices. Therefore, machines without selvedge-forming systems may experience fewer interruptions. This is also valid for the fringed edge method.

[0030] Conclusion on Conventional Methods: Selvedge technique selection depends on weft insertion method, loom speed, material type, and product requirements. For high-speed looms, leno edges are favored. Folded edges are also viable in wide- width applications where edge quality and fabric weight are critical.

[0031] Among all options, rapier looms support all edge types, but at higher speeds, efficiency demands push toward leno edges. Folded edges are typically found in towel production — wide and low-speed weaving with neat edge requirements. Jet looms avoid folded edges due to incompatibility with speed, instead favoring leno structures.

[0032] As jet loom applications (including jacquard) expand, the prominence of leno edge systems is expected to rise.

[0033] In looms with shuttle weft insertion, folded edges are most common. However, at speeds over 300 RPM, leno edges become necessary.

[0034] Comparative studies reveal folded edges offer limited efficiency beyond certain widths and speeds. Manufacturers working at ~2000 RPM must choose between higher edge quality or maximum efficiency — ideally, both.

[0035] Undoubtedly, achieving both the desired quality and efficiency simultaneously is the main objective.

[0036] The leno device used in the known state of the technique attached to the Elsy machine and the leno device attached to the frame are identical in shape; however, they differ in dimensions. The leno device in the known state of the technique that is attached to the frame includes a locking mechanism that facilitates its attachment to the frame. In contrast, the leno device attached to the Elsy machine does not feature this locking mechanism. Nevertheless, the known leno device is designed to be compatible for attachment to the Elsy machine. Its working principle and function are the same. Both devices transform the fabric edges into a firm structure, maintaining the fabric’s integrity for subsequent processing stages. This is one of the most important indicators of fabric quality.

[0037] In terms of working principle, the known leno device used on the Elsy machine stands out among other edge weaving systems due to its ease of use on high speed machines and cost-effectiveness. It is compatible with dobby, jacquard, and air-jet weaving machines, thereby serving a broad range of edge weaving applications.

[0038] The metal flat blade in the known leno device operates within channels located between plastic rods. These channels are designed to allow the metal flat blade to move up and down. During this vertical motion, one of the plastic rods remains in the down position while the other is up. The leno device performs its weaving motion by twisting the weft yarn in a circular manner, with one yarn passing through the hole at the top of the metal flat blade and another yarn moving back and forth between the two plastic rods, thereby locking the weft yarn between them.

[0039] During this process, the upward movement of the metal flat blade is achieved via the upward motion of the Elsy machine. The downward movement, however, is enabled by magnets located at the bottom of the plastic rods. Without these magnets, the metal flat blade — having no weight or force above — would not descend, and the leno device would be unable to perform its function. As a result, the edge weaving would not be completed.

[0040] Magnetism is thus essential for the proper functioning of the known leno device. Errors in the fabric weave are typically caused by failures in this magnetic mechanism. Dust and lint accumulate in the channels where the metal flat blade operates, obstructing magnetism and resulting in fabric without proper edge weaving. Fabric lacking edge weaving is considered defective and leads to reduced efficiency. The amount of dust and lint accumulation depends on the warp yarns being used. While polyester and polyviscose yarns generate less dust, yarns like open-end, wool, cotton, and stragan produce significantly more. The operating conditions of the leno device are not the same for all yarns. In wool and cotton jobs, the functioning of the leno device becomes more difficult due to dust and lint accumulation. The channels where the metal blade operates fill up faster and require frequent cleaning. If not cleaned, the leno device cannot function properly, and machine downtime increases, further reducing efficiency. Although this issue is less frequent in polyester jobs, it still occurs. While such issues might arise a few times per week in polyester work, they may occur 3-5 times per shift in wool and cotton work. Since each machine includes two leno devices and one operator is responsible for several machines, the proper functioning of the leno device is crucial for determining how many machines an operator can oversee, the overall production efficiency, and the fabric quality produced by the facility.

[0041] Cleaning the leno device without disassembling it from the machine is very difficult, though not impossible. However, if cleaning is done without removing the device, the delicate structure of the leno device may become damaged. Breakage is also a potential risk during this process. The ideal approach is to remove the leno device from the frame or Elsy machine and clean it separately. Nevertheless, doing so repeatedly disrupts the operator’s workflow and causes a loss of control over the machines. Additionally, the disassembly, reassembly, and cleaning processes are time-consuming and labor-intensive. It is crucial that the operator recognizes the need for cleaning; however, until the problem is detected, the fabric woven during that time will lack proper edge weaving. As a result, both low efficiency and defective fabric are produced. In such cases, the number of machines an operator can handle becomes limited. Ultimately, producing both efficient and high-quality fabric becomes nearly impossible. Operators working in such conditions tend to become dissatisfied and begin seeking employment at facilities where the working environment is easier and more manageable. DESCRIPTION OF THE INVENTION

[0042] The invention eliminates the disadvantages described above.

[0043] Depending on the type of work carried out in factories, weaving operators are typically responsible for an average of 6-8 machines. By resolving the problems found in the known state of the technique, the number of machines an operator can manage increases, thereby significantly enhancing productivity.

[0044] In the leno device developed in this invention, a discharge hole has been created at the point of magnetization beneath the plastic rod. The flat metal blade operating within the channel facilitates the removal of dust, lint, and similar debris accumulated under the plastic rod through this discharge hole. Thanks to the invention, conditions that hinder magnetization are eliminated, allowing for up to 99% success even under the harshest conditions, at the highest speeds, and in the dustiest environments.

[0045] For instance, in Open-end fabric weaving, where this issue is most commonly encountered, the problem is completely prevented. Thus, the need for cleaning the leno device 3 to 5 times per shift is eliminated, and the leno device can operate without issues for up to six months. This is because the leno device developed in the invention self-cleans the accumulated dust through the discharge hole.

[0046] As a result, in Open-end applications, efficiency rates that were previously around 70-75% (including defective products) now reach 95-99% without errors. Accordingly, the number of machines a weaving operator can manage increases, while the operator’s labor burden is reduced. Thanks to the invention, as production increases, quality also reaches its highest levels, and in polyester-based operations, this problem becomes virtually nonexistent. With the elimination of the leno device cleaning process, productivity in weaving machines has increased remarkably. PARTS AND COMPONENTS

[0047] 1 . Leno Device in the Known State of the Technique

[0048] 1.1 Plastic Rod in the Known State of the Technique

[0049] 1.1.1 Channel in the Known State of the Technique

[0050] 1.1.2 Rear Surface Directly Opposite the Bottom of the Channel

[0051] 1.1.3 Housing

[0052] 2. Leno Device (as Developed in the Invention)

[0053] 2.1 Plastic Rod

[0054] 2.1.1 Channel

[0055] 2.1.2 Discharge Hole

[0056] 2.1.3 Magnet Housing

[0057] 3. Magnet

[0058] 4. Plastic Rod Protector

[0059] 5. Flat Metal Blade

[0060] A. Figure 17 shows the detailed view.

[0061] B. Figure 19 shows the detailed view.

[0062] BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1. Front view of the assembled leno device in the known state of the technique.

[0064] Figure 2. Right side view of the assembled leno device in the known state of the technique.

[0065] Figure 3. Left side view of the assembled leno device in the known state of the technique.

[0066] Figure 4. Front view of the assembled leno device in the known state of the technique, with the right-side plastic rod moved upward. Figure 5. Perspective view of the disassembled leno device in the known state of the technique.

[0067] Figure 6. Front view of the disassembled leno device in the known state of the technique.

[0068] Figure 7. Front perspective view of the plastic rod in the known state of the technique.

[0069] Figure 8. Left-side perspective view of the plastic rod in the known state of the technique.

[0070] Figure 9. Right-side view of the plastic rod in the known state of the technique.

[0071] Figure 10. Left-side view of the plastic rod in the known state of the technique.

[0072] Figure 11. Perspective view of the assembled leno device developed in the invention.

[0073] Figure 12. Front view of the assembled leno device developed in the invention.

[0074] Figure 13. Rear view of the assembled leno device developed in the invention.

[0075] Figure 14. Front view of the assembled leno device developed in the invention, with the right-side plastic rod moved upward.

[0076] Figure 15. Front perspective view of the plastic rod without the magnet.

[0077] Figure 16. Left-side perspective view of the plastic rod without the magnet.

[0078] Figure 17. Right-side view of the plastic rod.

[0079] Figure 18. Detailed view A. Figure 19. Left-side view of the plastic rod.

[0080] Figure 20. Detailed view B.

[0081] Figure 21. Front view of the disassembled leno device developed in the invention.

[0082] DESCRIPTION OF THE INVENTION

[0083] The leno device (1 ) in the known state of the technique operates with a flat metal blade (5) moving within channels (1.1.1 ) situated between two plastic rods (1.1 ). These channels (1.1.1 ) are designed to enable the up and down motion of the flat metal blade (5). During this vertical motion, one of the plastic rods (1.1 ) of the leno device (1) is positioned downward while the other is in the upward position.

[0084] The leno device (1 ) performs a weaving action by interlocking the weft yarn between an upper yarn passing through the hole on the top of the flat metal blade (5) and a free yarn situated between the two plastic rods (1.1 ), which alternates from right to left, creating a circular motion. This upward movement of the flat metal blade (5) is enabled by the upward motion of the Elsy device, while the downward movement is facilitated by magnets (3) located at the bottom of the plastic rods (1.1 ). Without the magnets (3), the flat metal blade (5) in the leno device (1), which lacks weight above it, cannot descend, and thus the leno device (1 ) cannot perform its function. As a result, edge weaving would not occur.

[0085] Magnetization is essential in the leno device (1) of the known technique. The main cause of weaving defects in the leno device (1 ) stems from this issue. Dust and lint accumulate within the channels (1.1.1 ) where the flat metal blade (5) operates, particularly on the inner surface near the magnets (3), which prevents magnetization and results in fabric lacking proper edge weaving. This unformed edge weave renders the fabric defective and reduces production efficiency.

[0086] The accumulation of dust and lint is directly related to the type of warp yarns used. Although it is relatively lower with polyester and polyviscose yarns, yarns such as open-end, wool, cotton, and stragan produce more dust, and the working conditions for the leno device (1) in these cases are different. In wool and cotton group applications, the leno device (1 ) struggles to operate properly due to the dust and lint, and the channels (1.1.1 ) where the flat metal blade (5) operates fill up quickly, requiring frequent cleaning. If not cleaned, the leno device (1) cannot function, and machine downtime further reduces efficiency. While the same issue is less frequent in polyester group applications, it still occurs. In polyester jobs, this issue may arise a few times per week, whereas in wool and cotton jobs, it may occur three to five times per shift. Since each machine contains two leno devices (1 ), and considering the number of machines a weaving operator is responsible for, the operability of the leno device (1 ) directly affects machine coverage, efficiency, and fabric quality in the enterprise.

[0087] Cleaning the leno device (1) in the known state without removing it from the machine is quite difficult, though not impossible. However, if cleaned without removal, the leno device (1 ) may suffer damage due to its delicate structure. Breakage may also occur during this process. The correct method is to remove the leno device (1 ) from the frame or Elsy machine for cleaning. Repeating this process disrupts the weaving operator's workflow and diminishes their control over the machines. Furthermore, the disassembly, cleaning, and reassembly process is time-consuming and labor-intensive. The need for cleaning must be noticed by the operator, but until it is, the fabric woven during that time lacks proper edge weaving. In such cases, both productivity and product quality are compromised, limiting the number of machines an operator can manage. As a result, it becomes nearly impossible for the facility to produce fabric that is both efficient and of high quality. Weaving operators tend to avoid working in such companies and instead seek jobs with easier conditions.

[0088] Due to the dust and lint from the yarns during machine operation, the lower part of the channel (1.1.1 ) in the known leno device (1) becomes filled. This accumulation reduces the magnetic effect of the magnet (3) on the flat metal blade (5), preventing proper edge weaving. Cleaning this dust and lint takes time and causes production losses. Additionally, if the leno device (1 ) is cleaned without removal from the machine, it may break, crack, or become deformed. As implied by its name, the channel (1.1.1) is a cavity. Therefore, removing the accumulated dust and lint from the lower part of the channel (1.1.1) is difficult and time-consuming. Without cleaning, this dust and lint cannot be removed on their own.

[0089] The rear surface (1.1.2) directly opposite the lower part of the channel (1.1.1 ) is closed. Thus, removing the dust and lint from the channel (1.1.1) is difficult and time-consuming.

[0090] The known leno device (1) consists of two plastic rods (1.1 ), four magnets (3), and one flat metal blade (5). In some versions, a plastic rod protector (4) is also included. The plastic rod protectors (4) are mounted onto designated points on the plastic rod (1.1 ), with each rod holding two protectors. Two magnets (3) are inserted into two slots (1.1.3) located on opposing surfaces of the plastic rod (1.1). One foot of the flat metal blade (5) is inserted into a channel (1.1.1) on one plastic rod (1.1 ), and the other foot into the channel (1.1.1) of the opposite rod (1.1 ), thus completing the assembly of the leno device (1 ).

[0091] In the leno device (2) developed in the invention, a discharge hole (2.1.2) is formed at the point of magnetization at the bottom of the plastic rod (2.1 ). The flat metal blade (5) operating inside the channel (2.1.1 ) enables the discharge of dust and lint accumulated at the bottom of the plastic rod (2.1) through the discharge hole (2.1.2). Thanks to the invention, the conditions preventing magnetization are eliminated, achieving up to 99% success even under harsh conditions, at high speeds, and with dusty jobs. For example, in open-end fabric weaving, where this issue is most commonly encountered, it does not occur at all. As a result, the need for cleaning the leno device (1 ) three to five times per shift is eliminated, and the leno device (2) can function flawlessly for up to six months. This is because the leno device (2), developed in the invention, self-cleans the dust through the discharge hole (2.1.2). Consequently, efficiencies in open-end jobs that were previously 70- 75% (including defects) rise to 95-99% error-free. Thus, the number of machines a weaving operator can manage increases, while their workload decreases. Thanks to the invention, as production increases, quality reaches the highest levels, and the problem disappears in polyester-based work. With the elimination of the leno device (2) cleaning process, productivity in weaving machines has increased remarkably.

[0092] The invention is a leno device (2) comprising:

[0093] - A discharge hole (2.1.2) located at the magnetization point at the bottom of the plastic rod (2.1 ), aligned with the channel (2.1.1 ).

[0094] The discharge hole (2.1.2) is positioned on the plastic rod (2.1) along a horizontal axis. One magnet (3) is placed in each of the magnet slots (2.1.3) located in front and behind the discharge hole (2.1.2).

[0095] The foot of the flat metal blade (5) moving within the channel (2.1.1 ) pushes dust and lint from the yam toward the discharge hole (2.1.2). The dust and lint pushed into the discharge hole (2.1.2) are expelled to the external environment due to the pressure from the flat metal blade (5), thus eliminating the need to clean the channel (2.1.1 ).

[0096] The discharge hole (2.1.2) may be manufactured in any suitable geometry (rectangular, square, circular, etc.).

[0097] The leno device (2) consists of two plastic rods (2.1 ), four magnets (3), and one flat metal blade (5). Some versions also include plastic rod protectors (4). These protectors (4) are mounted on designated points on the plastic rods (2.1), with each rod fitted with two protectors. Two magnets (3) are inserted into two opposing magnet slots (2.1.3) on the plastic rod (2.1 ). One foot of the flat metal blade (5) is inserted into a channel (2.1.1 ) on one plastic rod (2.1 ), and the other foot into the channel (2.1.1) on the opposite rod (2.1), thus completing the assembly of the leno device (2).

[0098] In another embodiment of the invention, if necessary, a compressed air line taken from the machine’s existing air-blowing system may be directed toward the discharge hole (2.1.2) on the leno device (2), to provide periodic cleaning of even the smallest lint or dust accumulation. In this way, the air directed into the discharge hole (2.1.2) ensures that even the smallest dust or lint particles are cleared

Claims

CLAIMS1. The invention is a leno device (2), characterized in that it comprises ;- a discharge hole (2.1.2) positioned at the point where magnetization occurs on the lower part of the plastic rod (2.1 ), and aligned with the channel (2.1.1 ).

2. The leno device (2) according to Claim 1 , characterized in that it comprises: a discharge hole (2.1.2) that allows dust and lint, which are pushed by the foot of the flat metal blade (5) moving within the channel (2.1.1 ), to exit freely to the outside due to its connection with the channel (2.1.1).

3. The leno device (2) according to Claim 1 , characterized in that it comprises; a discharge hole (2.1.2) positioned to receive airflow from an air line connected to the existing air-blowing system of the machine on which the leno device (2) is mounted, to ensure the removal of accumulated dust and lint.

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