Sliding zipper belt tooth thermoplastic forming equipment and its forming process

Abstract

The present application relates to the field of slide fastener tape forming, in particular to a sliding type slide fastener tape tooth thermoplastic forming equipment and a forming process thereof, comprising a conveying device for forming the teeth of the slide fastener tape surface, a forming mechanism, a pressing wheel and an adjusting motor arranged above the conveying device, the pressing wheel and the adjusting motor are symmetrically arranged on both sides of the upper end of the conveying device, and the slide fastener tape is arranged above the conveying device, in the present application, the support bar in the female chain support assembly can effectively solve the problem, when the slide fastener tape enters the forming mechanism and needs to be formed into a female chain, the electric push rod drives the connecting plate, drives the support bar to accurately extend into the upper die or the lower die along the guide rod, and penetrates the structure corresponding to the female chain forming area. The support bar temporarily fills the middle part of the female chain during thermoplastic process to accommodate the opening area of the male chain, provides rigid support for the suspended part, and prevents the hot melt adhesive from collapsing and deforming due to gravity or pressure before cooling.

Description

Technical Field

[0001] This invention relates to the field of zipper tape molding, specifically a sliding zipper tape toothed thermoplastic molding equipment and its molding process. Background Technology

[0002] In existing molding mechanisms, when molding the zipper mother chain, there is a partially suspended structure on the surface of the mother chain because the middle of the teeth of the mother chain is an opening for the sub-chains to pass through. Therefore, an additional support mechanism is required during thermoforming and then withdraws from the molding mechanism to form the suspended structure on the surface of the mother chain. However, existing molding methods all rely on manually inserting inserts to form a support effect on the main structure of the mother chain, which is not ideal.

[0003] Secondly, after the zipper with teeth is formed, it is usually collected by winding roller. When the zipper is rolled, the side closer to the teeth is higher than the other side, which causes the subsequent winding to gradually become skewed. When the zipper strip is skewed during winding, it will affect the zipper strip that is still in the stage of forming teeth. This will cause the zipper strip in that section to deviate from the original thermoplastic processing end face under force, affecting the actual forming effect. Summary of the Invention

[0004] This invention provides a sliding zipper tape toothed thermoplastic molding device, which overcomes the shortcomings described in the background art.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A sliding zipper tape toothed thermoplastic molding equipment includes a conveying device for molding the toothed surface of the zipper tape, and a molding mechanism, a pressure roller, and an adjusting motor disposed above the conveying device. The pressure roller and the adjusting motor are symmetrically disposed on both sides of the upper end of the conveying device, and the zipper tape is disposed above the conveying device.

[0007] The pressing wheel is located between the forming mechanism and the adjusting motor, and the pressing wheel is driven to rotate by the convex ring. The adjusting motor is located on the front and rear sides of the conveying device, and a rubber wheel is installed on the output shaft of the adjusting motor. The rubber wheel abuts against the surface of the zipper belt. The rubber wheel is inclined. When the zipper belt passes under the rubber wheel, the rubber wheel pushes the zipper belt to move away from the pressing wheel.

[0008] The conveying device includes a drive wheel and symmetrically arranged conveyor belt bodies, each of which is equipped with a zipper belt.

[0009] The forming mechanism includes an upper mold and a lower mold disposed on the upper and lower sides of the zipper tape. The sides of the upper mold and the lower mold are symmetrically provided with a mother chain support assembly. The mother chain support assembly includes an electric push rod, a connecting plate, a support bar, and a guide rod. The electric push rod is fixed to the back of the corresponding upper mold or lower mold. The output shaft of the electric push rod is connected to the support bar and the guide rod through the connecting plate. The support bar and the guide rod both extend toward the corresponding upper mold or lower mold.

[0010] The upper and lower mold surfaces are each equidistantly arranged with sub-chain forming grooves for forming sub-chains on the zipper tape and guide rods for forming the main chain on the zipper tape, with guide rods passing through each groove.

[0011] In a preferred technical solution, the adjacent ends of the two zipper tapes protrude from the side of the conveying device and are suspended in the air, so that the corresponding sub-chains and mother chains on the surfaces of the two zipper tapes can be formed by the forming mechanism respectively.

[0012] The surface of the conveyor belt body is provided with raised anti-slip strips, which extend along the length of the conveyor belt body. The circumferential surface of the pressure wheel is provided with an outwardly protruding ring. The rubber wheel of the adjusting motor output shaft is staggered with the ring. The raised anti-slip strip is located between the rubber wheel and the ring.

[0013] The raised ring and the raised anti-slip strip both abut against the surface of the zipper tape;

[0014] The zipper tape surface is raised at the corresponding points of the raised anti-slip strip.

[0015] In a preferred embodiment, a positioning hole is provided on the side of the forming mechanism corresponding to the guide rod. When the electric push rod retracts the output shaft, the guide rod is inserted into the positioning hole.

[0016] In a preferred embodiment, the molding mechanism includes an injection molding mechanism disposed on the side of the molding mechanism. The injection molding mechanism includes an injection tube, a connecting tube, and a solenoid valve. The injection tube is connected to all corresponding zipper tapes or all corresponding mother chain molding grooves. The injection tube is connected to a hot melt glue machine and a water pump through two solenoid valves. A connecting tube is provided at the connection end of the injection tube and the two solenoid valves.

[0017] In a preferred embodiment, the molding mechanism further includes screw transmission mechanisms symmetrically arranged on the front and rear sides of the molding mechanism. Each screw transmission mechanism includes drive groups symmetrically arranged vertically. The drive group includes a motor, a motor, and a limiting rod. A screw is provided on the output shaft of the motor, and a screw is provided on the output shaft of the motor. A positioning slider is installed at the end of the screw, and a limiting rod passes through the middle of the positioning slider. A screw slider is provided on the back of the motor, and the screw passes through the screw slider.

[0018] The upper or lower die is connected to the corresponding screw via a lead screw slider 1 set on its surface.

[0019] A sliding zipper tape with teeth thermoplastic molding process, based on the aforementioned sliding zipper tape with teeth thermoplastic molding equipment, wherein when molding the sliding zipper tape with teeth, the zipper tapes to be molded into sub-chains or mother chains are placed sequentially on a conveying device, and the zipper tapes are conveyed by the conveying device, so that the zipper tapes pass sequentially through a molding mechanism, a pressure roller, and an adjusting motor, and when passing through the molding mechanism, the corresponding sub-chains and mother chains are respectively injection molded on the surface of the zipper tapes;

[0020] When the zipper tape passes through the forming mechanism and is injection molded into the main chain, the output shaft of the electric push rod is driven to pass the support bars through each one in sequence. Hot melt glue is injected into the forming mechanism through the hot melt glue machine connected to the injection mechanism on the side of the forming mechanism, and then the main chain is formed.

[0021] A preferred technical solution: Compared with the prior art, this technical solution has the following advantages:

[0022] This invention effectively solves the problem through a support strip in the main chain support assembly. When the zipper tape enters the molding mechanism and the main chain needs to be formed, an electric push rod drives the connecting plate, causing the support strip to precisely extend into the upper or lower mold along the guide rod, penetrating the structure of the corresponding main chain forming area. During the thermoplastic process, this support strip temporarily fills the opening area in the middle of the main chain used to accommodate the sub-chains, providing rigid support for the suspended parts and preventing the hot melt adhesive from collapsing or deforming due to gravity or pressure before cooling. After thermoplasticizing is complete and the adhesive has initially solidified, the electric push rod ejects the support strip without manual intervention.

[0023] To address the issue of zipper tape skewing due to the high height of the toothed side, which negatively impacts the positioning of the thermoplastic end face, this solution utilizes the coordinated action of a pressure roller and an adjusting motor to achieve dynamic correction. Specifically, the adjusting motor is positioned on both sides of the conveyor, with a rubber wheel on its output shaft pressing against the surface of the zipper tape at an angle. As the zipper tape passes under the rubber wheel, the angled wheel applies a lateral thrust, slightly displacing the zipper tape away from the pressure roller. This displacement direction is opposite to the direction of the tension force generated by the skewing, thus counteracting the deviation trend in real time. The pressure roller provides stable clamping force on the other side, ensuring the zipper tape remains straight and centered at the forming mechanism. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Figure 1 This is an overall diagram of the present invention.

[0026] Figure 2 This is a schematic diagram of the forming mechanism.

[0027] Figure 3 This is a schematic diagram of the clamping wheel.

[0028] Figure 4 This is a schematic diagram of the structure when the support bar is not inserted.

[0029] Figure 5 This is a schematic diagram showing the positional relationship between the raised anti-slip strip, the raised ring, and the zipper tape.

[0030] Figure 6 This is a side view of the zipper strap and the raised anti-slip strip.

[0031] Figure 7 for Figure 3 Enlarged schematic diagram of point a in the middle.

[0032] Figure 8 This is a schematic diagram of the injection molding tube and solenoid valve from another perspective.

[0033] Figure 9 This is a structural diagram of the support bar and guide rod.

[0034] Figure 10 This is a schematic diagram of the zipper tape after the main and secondary chains are formed.

[0035] In the diagram: 1. Conveying device; 2. Forming mechanism; 3. Pressing roller; 4. Adjusting motor; 100. Zipper belt; 200. Main chain forming groove; 300. Sub-chain forming groove;

[0036] 11. Drive wheel; 12. Conveyor belt body; 13. Raised anti-slip strip;

[0037] Upper mold 21, lower mold 22, drive assembly 23, lead screw and slider 24, main chain support assembly 25, injection molding mechanism 26;

[0038] Motor 1 231, Screw 1 2311, Motor 2 232, Screw 2 2321, Lead Screw Slider 2 2322, Positioning Slider 2323, Limiting Rod 233;

[0039] Electric push rod 251, connecting plate 252, support bar 253, guide rod 254;

[0040] Injection molding pipe 261, connecting pipe 262, solenoid valve 263;

[0041] Raised ring 31. Detailed Implementation

[0042] like Figures 1 to 10As shown, the present invention proposes a sliding zipper tape toothed thermoplastic molding equipment, including a conveying device 1 for molding the toothed surface of the zipper tape 100, and a molding mechanism 2, a pressing wheel 3, and an adjusting motor 4 disposed above the conveying device 1. The pressing wheel 3 and the adjusting motor 4 are symmetrically arranged on both sides of the upper end of the conveying device 1, and the zipper tape 100 is disposed above the conveying device 1.

[0043] The pressing wheel 3 is disposed between the forming mechanism 2 and the adjusting motor 4, and the pressing wheel 3 is driven to rotate by the convex ring 31. The adjusting motor 4 is disposed on the front and rear sides of the conveying device 1, and a rubber wheel is mounted on the output shaft of the adjusting motor 4. The rubber wheel abuts against the surface of the zipper belt 100. The rubber wheel is inclined. When the zipper belt 100 passes under the rubber wheel, the rubber wheel pushes the zipper belt 100 to move away from the pressing wheel 3.

[0044] The conveying device 1 includes a drive wheel 11 and symmetrically arranged conveyor belt bodies 12, each of which is provided with a zipper belt 100.

[0045] The forming mechanism 2 includes an upper mold 21 and a lower mold 22 disposed on the upper and lower sides of the zipper tape 100. The sides of the upper mold 21 and the lower mold 22 are symmetrically provided with a mother chain support assembly 25. The mother chain support assembly 25 includes an electric push rod 251, a connecting plate 252, a support bar 253 and a guide rod 254. The electric push rod 251 is fixed to the back of the corresponding upper mold 21 or lower mold 22. The output shaft of the electric push rod 251 is connected to the support bar 253 and the guide rod 254 through the connecting plate 252. The support bar 253 and the guide rod 254 both extend toward the corresponding upper mold 21 or lower mold 22.

[0046] The surfaces of the upper mold 21 and the lower mold 22 are equally spaced with mother chain forming grooves 200 for forming the sub-chains on the zipper tape and daughter chain forming grooves 300 for forming the mother chain on the zipper tape. The guide rod 254 passes through each mother chain forming groove 200.

[0047] Based on the above, this invention also proposes a sliding zipper belt toothed thermoplastic molding process. Based on the aforementioned sliding zipper belt toothed thermoplastic molding equipment, when molding the sliding zipper belt toothed, the zipper belt 100 that needs to be molded into a sub-chain or a main chain is placed sequentially on the conveying device 1, and the zipper belt 100 is conveyed by the conveying device 1, so that the zipper belt 100 passes sequentially through the molding mechanism 2, the pressure roller 3, and the adjusting motor 4. When passing through the molding mechanism 2, the molding mechanism 2 respectively injection molds the corresponding sub-chain and main chain on the surface of the zipper belt 100.

[0048] When the zipper tape 100 passes through the molding mechanism 2 and is injection molded into the mother chain, the output shaft of the electric push rod 251 is driven to pass the support bar 253 through each mother chain molding groove 200 in sequence, and hot melt glue is injected into the molding mechanism 2 through the hot melt glue machine connected to the injection molding mechanism 26 located on the side of the molding mechanism 2, and the mother chain is formed through the mother chain molding groove 200.

[0049] In the above technical solution, the problem of the suspended main chain structure is effectively solved by the support strip 253 in the main chain support component 25. When the zipper tape 100 enters the molding mechanism 2 and the main chain needs to be molded, the electric push rod 251 drives the connecting plate 252, causing the support strip 253 to precisely extend into the upper mold 21 or lower mold 22 along the guide rod 254, and penetrate through the main chain molding groove 200 structure of the corresponding main chain molding area. During the thermoplastic process, the support strip 253 temporarily fills the opening area in the middle of the main chain used to accommodate the sub-chain, providing rigid support for the suspended part and preventing the hot melt adhesive from collapsing and deforming due to gravity or pressure before cooling. After the thermoplastic process is completed and the adhesive has initially solidified, the electric push rod 251 pushes out the support strip 253 without manual intervention. This process realizes automated and precise support for the suspended main chain structure, significantly improving molding accuracy and consistency.

[0050] Furthermore, this solution integrates an electric pusher-driven support strip system, enabling automatic support and disengagement of the suspended main chain structure during the thermoplastic process. This avoids problems such as inaccurate positioning, low efficiency, and product yield fluctuations caused by traditional manual strip insertion. Simultaneously, the adjusting motor 4, in conjunction with the tilting rubber wheel, dynamically corrects the zipper tape 100 laterally, effectively suppressing offset caused by thickness asymmetry during the winding stage, thus ensuring stable stress on the thermoplastic end face and molding quality. The overall process is continuous and highly automated, significantly improving production efficiency and product consistency.

[0051] To address the issue of the zipper tape 100 being misaligned during winding due to its high toothed side height, which in turn affects the positioning of the thermoplastic end face, this solution achieves dynamic correction through the coordinated action of the pressure roller 3 and the adjusting motor 4. Specifically, the adjusting motor 4 is positioned on both sides of the conveyor device 1, with a rubber wheel on its output shaft pressing against the surface of the zipper tape 100 at an angle. When the zipper tape 100 passes under the rubber wheel, the angled rubber wheel applies a lateral thrust, pushing the zipper tape 100 to a slight displacement away from the pressure roller 3. This displacement direction is opposite to the direction of the tension generated by the winding misalignment, thus counteracting the offset trend in real time. The pressure roller 3 provides stable clamping force on the other side, ensuring that the zipper tape 100 remains straight and centered at the forming mechanism 2.

[0052] Furthermore, the adjacent ends of the two zipper tapes 100 protrude from the side of the conveying device 1 and are suspended in the air, so that the forming mechanism 2 can form the corresponding sub-chains and mother chains on the surfaces of the two zipper tapes 100 respectively.

[0053] The surface of the conveyor belt body 12 is provided with a raised anti-slip strip 13, which extends along the length of the conveyor belt body 12. The circumferential surface of the pressure wheel 3 is provided with an outwardly protruding ring 31. The rubber wheel of the output shaft of the adjusting motor 4 is staggered from the ring 31. The raised anti-slip strip 13 is located between the rubber wheel and the ring 31.

[0054] The convex ring 31 and the raised anti-slip strip 13 both abut against the surface of the zipper tape 100;

[0055] The surface of the zipper tape 100 is raised at the corresponding position of the raised anti-slip strip 13.

[0056] The conveyor device 1, consisting of two conveyor belt bodies 12, aims to achieve synchronous processing through dual channels. Since the two zipper belts 100 need to form the sub-chain and the main chain respectively, their structures are complementary but their process paths are consistent. The symmetrical parallel dual-conveyor belt layout allows the two zipper belts to simultaneously complete the forming of their respective tooth profiles under the same forming mechanism 2, improving equipment utilization and production efficiency. Simultaneously, the adjacent ends of the two zipper belts 100 protrude from the sides of the conveyor device 1, providing sufficient space for the upper mold 21 and lower mold 22 in the forming mechanism 2. This ensures that the forming areas of the sub-chain and the main chain are not obstructed by the conveyor structure, especially facilitating the complete forming of the opening structure in the middle of the main chain and the smooth insertion and removal of the support strip 253.

[0057] The raised anti-slip strip 13 and the raised ring 31 on the circumferential surface of the pressure wheel 3 together constitute a longitudinal limiting and lateral clamping positioning system for the zipper belt 100. Specifically, the raised anti-slip strip 13 on the conveyor belt body 12 extends along the length direction and forms a corresponding ridge at the contact point with the bottom surface of the zipper belt 100, which not only enhances friction to prevent slippage, but also restricts the longitudinal movement of 100 in the conveying direction through shape matching; while the raised ring 31 on the pressure wheel 3 presses against the surface of 100 from above, forming an upper and lower alignment clamp with the raised anti-slip strip 13 below. Since the rubber wheel of the adjusting motor 4 and the raised ring 31 are arranged in a staggered manner, and both act on different axial positions of 100, 100 is constrained by a "three-point support" during movement: the front is subjected to the lateral thrust of the rubber wheel, the middle section is vertically pressed by the raised ring 31, and the bottom is supported and positioned by 13. This structure effectively suppresses the vertical jump, lateral shift, and longitudinal slippage of 100 during the thermoplastic process, ensuring that it maintains a precise and stable posture within the molding mechanism 2.

[0058] The molding mechanism 2 has a positioning hole on its side corresponding to the guide rod 254. When the electric push rod 251 retracts its output shaft, the guide rod 254 is inserted into the positioning hole.

[0059] Furthermore, the molding mechanism 2 includes an injection molding mechanism 26 disposed on the side of the molding mechanism. The injection molding mechanism 26 includes an injection tube 261, a connecting tube 262, and a solenoid valve 263. The injection tube 261 is connected to all corresponding zipper tapes 100 or all corresponding mother chain molding grooves 200 respectively. The injection tube 261 is connected to a hot melt glue machine and a water pump through two solenoid valves 263 respectively. A connecting tube 262 is provided at the connection end of the injection tube 261 and the two solenoid valves 263. After the injection molding process is completed, the user can selectively open different solenoid valves to select the injection water flow to rinse the solution residue in the molding mechanism 2. During the rinsing process, the flowability of the solution can be improved by heating the heating wire disposed in the injection mechanism so that the residue can be carried out during the water flow.

[0060] Furthermore, the molding mechanism 2 also includes screw drive mechanisms symmetrically arranged on the front and rear sides of the molding mechanism 2. Each screw drive mechanism includes a drive group 23 symmetrically arranged vertically. The drive group 23 includes a motor 1 231, a motor 232, and a limiting rod 233. The output shaft of the motor 1 231 is provided with a screw 1 2311, and the output shaft of the motor 232 is provided with a screw 2321. A positioning slider 2323 is installed at the end of the screw 2321. A limiting rod 233 passes through the middle of the positioning slider 2323. A screw slider 2322 is provided on the back of the motor 232. The screw 1 2311 passes through the screw slider 2322.

[0061] The upper mold 21 or the lower mold 22 are respectively connected to the corresponding screw 2321 via the lead screw slider 24 provided on its surface.

[0062] The above description is merely a preferred embodiment of the present invention, and therefore should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A sliding zipper tape toothed thermoplastic molding equipment, characterized in that, The device includes a toothed conveyor for forming the surface of the zipper tape, a forming mechanism, a pressing wheel, and an adjusting motor disposed above the conveyor. The pressing wheel and the adjusting motor are symmetrically arranged on both sides of the upper end of the conveyor, and the zipper tape is disposed above the conveyor. The pressing wheel is positioned between the forming mechanism and the adjusting motor. The circumferential surface of the pressing wheel has an outwardly protruding ring that abuts against the surface of the zipper belt to drive the pressing wheel to rotate. The adjusting motors are respectively positioned on the front and rear sides of the conveying device, and a rubber wheel is mounted on the output shaft of the adjusting motor. The rubber wheel abuts against the surface of the zipper belt and is inclined. When the zipper belt passes under the rubber wheel, the rubber wheel pushes the zipper belt to move away from the pressing wheel. The conveying device includes a drive wheel and symmetrically arranged conveyor belt bodies, each of which is equipped with a zipper belt. The forming mechanism includes an upper mold and a lower mold disposed on the upper and lower sides of the zipper tape. The sides of the upper mold and the lower mold are symmetrically provided with a mother chain support assembly. The mother chain support assembly includes an electric push rod, a connecting plate, a support bar, and a guide rod. The electric push rod is fixed to the back of the corresponding upper mold or lower mold. The output shaft of the electric push rod is connected to the support bar and the guide rod through the connecting plate. The support bar and the guide rod both extend toward the corresponding upper mold or lower mold. The upper and lower mold surfaces are each equidistantly arranged with sub-chain forming grooves for forming sub-chains on the zipper tape and mother chain forming grooves for forming mother chains on the zipper tape, and guide rods pass through each mother chain forming groove.

2. The sliding zipper tape toothed thermoplastic molding equipment according to claim 1, characterized in that, The adjacent ends of the two zipper tapes protrude from the side of the conveyor device and are suspended in the air, so that the corresponding sub-chains and mother chains on the surfaces of the two zipper tapes can be formed by the forming mechanism respectively. The surface of the conveyor belt body is provided with raised anti-slip strips, which extend along the length of the conveyor belt body. The circumferential surface of the pressure wheel is provided with an outwardly protruding ring. The rubber wheel of the adjusting motor output shaft is staggered with the ring. The raised anti-slip strip is located between the rubber wheel and the ring. The raised ring and the raised anti-slip strip both abut against the surface of the zipper tape; The zipper tape surface is raised at the corresponding points of the raised anti-slip strip.

3. The sliding zipper tape toothed thermoplastic molding equipment according to claim 2, characterized in that, The molding mechanism has a positioning hole on its side corresponding to the guide rod. When the electric push rod retracts its output shaft, the guide rod is inserted into the positioning hole.

4. The sliding zipper tape toothed thermoplastic molding equipment according to claim 1, characterized in that, The molding mechanism includes an injection molding mechanism disposed on the side of the molding mechanism. The injection molding mechanism includes an injection tube, a connecting tube, and a solenoid valve. The injection tube is connected to all corresponding zipper tapes or all corresponding mother chain molding grooves. The injection tube is connected to a hot melt glue machine and a water pump through two solenoid valves. A connecting tube is provided at the connection end of the injection tube and the two solenoid valves.

5. A sliding zipper belt toothed thermoplastic molding equipment according to claim 4, characterized in that, The forming mechanism also includes screw transmission mechanisms symmetrically arranged on the front and rear sides of the forming mechanism. Each screw transmission mechanism includes drive groups symmetrically arranged vertically. The drive group includes motor one, motor two, and a limiting rod. Screw one is provided on the output shaft of motor one, and screw two is provided on the output shaft of motor two. A positioning slider is installed at the end of screw two. A limiting rod passes through the middle of the positioning slider. Screw slider two is provided on the back of motor two. Screw one passes through screw slider two. The upper or lower die is connected to the corresponding screw via a lead screw slider 1 set on its surface.

6. A sliding zipper tape with toothed thermoplastic molding process, based on the sliding zipper tape with toothed thermoplastic molding equipment according to claim 5, characterized in that, When forming a sliding zipper belt with teeth, the zipper belts that need to be formed into sub-chains or mother chains are placed on the conveyor device in sequence, and the zipper belts are conveyed by the conveyor device so that the zipper belts pass through the forming mechanism, the pressure roller, and the adjusting motor in sequence. When passing through the forming mechanism, the forming mechanism injects and molds the corresponding sub-chains and mother chains on the surface of the zipper belt respectively. When the zipper tape passes through the forming mechanism and is injection molded into the main chain, the output shaft of the electric push rod is driven to pass the support bar through each main chain forming groove in sequence. Hot melt glue is injected into the forming mechanism through the hot melt glue machine connected to the injection mechanism on the side of the forming mechanism, and the main chain is formed through the main chain forming groove.

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