A fixed-length wire stripping device for automobile wire processing

Abstract

The application discloses a fixed-length wire stripping device for automobile wire processing and relates to the technical field of automobile wire processing equipment. The fixed-length wire stripping device comprises a box body, a rectangular box, a threading hole, a wire stripping mechanism, a fixed-length mechanism, a skin cutting mechanism and a collecting mechanism. The fixed-length mechanism comprises rectangular plates symmetrically arranged on one side surface of the rectangular box, upper and lower fixed plates symmetrically arranged between the rectangular plates, a plurality of arc-shaped grooves of various specifications uniformly arranged on the upper and lower fixed plates, and a micro electric push rod arranged symmetrically on the upper and lower fixed plates. An electric telescopic rod is arranged symmetrically on each rectangular plate. The fixed-length mechanism is used for accurately adjusting the length of the wire extending out of the wire stripping mechanism through the electric telescopic rod, and the upper and lower fixed plates driven by the micro electric push rod are used for stably clamping the wire, so that the fixed-length wire stripping of different length specifications can be accurately realized. The fixed-length adjustment operation is convenient, no additional accessories need to be replaced, and the fixed-length processing requirements of diversified automobile wires are met.

Description

Technical Field

[0001] This invention relates to the field of automotive wire processing equipment technology, and in particular to a fixed-length wire stripping device for automotive wire processing. Background Technology

[0002] As a core component of automotive circuits, the processing precision of automotive wires directly affects the assembly quality and operational safety of the automotive circuitry. Length stripping is a crucial process in automotive wire processing, requiring precise stripping lengths, complete sheathing, and no damage to the internal wire cores. Currently available automotive wire length stripping equipment often uses fixed-size limiting components for stripping wires of different specifications. This only accommodates single-length wires. Adjusting the stripping length requires manual replacement of different-sized limiting components, which is cumbersome and prone to errors due to component misalignment. Furthermore, existing wire clamping structures are often rigid, which are susceptible to wire slippage and displacement during clamping, further reducing length accuracy and failing to meet the high precision requirements for stripping lengths in automotive wire processing. Summary of the Invention

[0003] In order to solve the problems in the background art, the present invention proposes a fixed-length wire stripping device for automotive wire processing.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A wire stripping device for automotive wire processing includes a housing, a rectangular box disposed on the top surface of the housing, and various sizes of wire-passing holes evenly formed on the rectangular box, and further includes: A wire stripping mechanism, located in the middle of the housing, is used to strip automotive electrical wires. A length-limiting mechanism is provided on one side of a rectangular box for limiting the length of automotive wiring. A skin-cutting mechanism, which is disposed inside a rectangular box and close to the fixed-length mechanism on one side; A collection mechanism, located inside the box, is used to clean the cut skin; The fixed length mechanism includes rectangular plates symmetrically arranged on one side of a rectangular box, an upper fixed plate and a lower fixed plate symmetrically arranged between the rectangular plates, and arc-shaped grooves of various specifications are evenly opened on the upper fixed plate and the lower fixed plate. A miniature electric actuator is symmetrically provided on both the upper and lower fixed plates, and the fixed end of the miniature electric actuator is fixedly connected to the rectangular plate. Each of the rectangular plates is symmetrically provided with an electric telescopic rod, and the fixed end of the electric telescopic rod is set inside the rectangular box.

[0005] Preferably, the wire stripping mechanism includes a connecting shaft one and a connecting shaft two symmetrically rotated within a rectangular box. The outer wall of the connecting shaft one is uniformly fixed with lower wire stripping blades of different specifications, and the outer wall of the connecting shaft two is uniformly fixed with a plurality of upper wire stripping blades that cooperate with the lower wire stripping blades.

[0006] Preferably, one end of the connecting shaft one and the connecting shaft two extends movably through the rectangular box, a gear two is fixedly connected to the outer wall of the connecting shaft one, and a gear one that meshes with the gear two is provided on the outer wall of the connecting shaft two.

[0007] Preferably, a pulley is fixedly connected to the outer wall of one end of the connecting shaft, a servo motor is installed inside the housing, a pulley is fixedly connected to the output shaft of the servo motor, a rectangular opening is provided on the top surface of the housing, and the pulley and the pulley are connected by a belt, with the belt passing through the rectangular opening.

[0008] Preferably, the rectangular box has a protective shell on its side, and the second pulley, the second gear, and the first gear are all disposed inside the protective shell.

[0009] Preferably, the skinning mechanism includes a linear motor mounted on the top surface of the housing and a slider mounted on the linear motor. An electric telescopic rod II is mounted on the bottom surface of the slider. An installation plate I is fixedly connected to the movable end of the electric telescopic rod II. A miniature electric push rod II is mounted on the bottom surface of the installation plate I. The movable end of the miniature electric push rod II is fixedly connected to the installation plate II. An upper cutting blade is fixedly attached to the bottom surface of the mounting plate one, and a lower cutting blade that cooperates with the upper cutting blade is fixedly attached to the top surface of the mounting plate two.

[0010] Preferably, the collection mechanism includes a discharge port on the top surface of the box, and a collection box is slidably provided at the bottom of the discharge port via a sliding member.

[0011] Preferably, the sliding member includes a slide rail symmetrically arranged at the bottom edge of the discharge port, a slide block is slidably provided in the slide rail, and the slider is fixed to the outer wall of the collection box.

[0012] Preferably, a rubber pad is fixed to the inner wall of the arc-shaped groove.

[0013] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The length-fixing mechanism in this invention precisely adjusts the length of the wire extending out of the stripping mechanism through an electric telescopic rod, and the upper and lower fixing plates driven by a miniature electric push rod stably clamp the wire. The rubber pad on the inner wall of the arc groove ensures the stability of the clamping limit and avoids damaging the wire. It can achieve precise length-fixed stripping of different length specifications. The length-fixed adjustment operation is convenient and does not require the replacement of additional parts, thus meeting the diverse length-fixed processing needs of automotive wires. 2. The rectangular box in this invention has wire holes of various specifications. The arc groove of the length-fixing mechanism, the wire stripping knife group of the wire stripping mechanism, and the cutting knife group of the insulation cutting mechanism all correspond one-to-one with the specifications of the wire holes. Moreover, the insulation cutting mechanism can adjust the distance between the cutting knives by means of a miniature electric push rod. The wire stripping mechanism is equipped with upper and lower wire stripping knives of different specifications, which can be adapted to the processing of automotive wires of different diameters. There is no need to equip special equipment for wires of different specifications, which greatly improves the versatility and applicability of the device.

[0014] 3. This invention integrates four major functions: length setting, sheath cutting, wire stripping, and collection. The various mechanisms work together in a coordinated manner. After the wire is threaded and positioned, the entire process of length setting, sheath cutting, wire stripping, and sheath collection can be completed sequentially. No manual transfer or operation is required. The wire stripping mechanism achieves synchronous reverse rotation of the upper and lower stripping blades through gear meshing, resulting in fast stripping speed and good stripping effect. The sheath cutting mechanism achieves precise and rapid adjustment of the cutting position through a linear motor and electric telescopic rod. The whole process can realize continuous processing of automotive wires, greatly improving the overall efficiency of wire stripping. Attached Figure Description

[0015] Figure 1 A schematic diagram of the structure from a frontal view provided according to an embodiment of the present invention is shown; Figure 2 A schematic diagram of the structure from a side view provided according to an embodiment of the present invention is shown; Figure 3 A side-view cross-sectional structural schematic diagram is shown according to an embodiment of the present invention; Figure 4 A top-view cross-sectional structural diagram is shown according to an embodiment of the present invention; Figure 5 A schematic cross-sectional view of the structure provided in an embodiment of the present invention is shown; Figure 6 A schematic diagram of the wire stripping mechanism provided according to an embodiment of the present invention is shown; Figure 7 A schematic diagram of the skin-cutting mechanism provided according to an embodiment of the present invention is shown; Figure 8 A schematic diagram of the fixed-length mechanism provided according to an embodiment of the present invention is shown.

[0016] Legend: 1. Box body; 2. Rectangular box; 3. Collection box; 4. Rectangular plate; 5. Miniature electric actuator one; 6. Upper fixing plate; 7. Lower fixing plate; 8. Protective shell; 9. Belt; 10. Belt pulley one; 11. Belt pulley two; 12. Servo motor; 13. Electric telescopic rod one; 14. Wire hole; 15. Connecting shaft one; 16. Discharge port; 17. Gear one; 18. Gear two; 19. Lower wire stripper; 20. Upper wire stripper; 21. Connecting shaft two; 22. Linear motor; 23. Slider; 24. Electric telescopic rod two; 25. Mounting plate one; 26. Miniature electric actuator two; 27. Lower cutting blade; 28. Upper cutting blade; 29. ​​Arc groove; 30. Rubber pad. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Please see Figure 1 - Figure 8 The present invention provides a technical solution: A length-fixed stripping device for automotive wire processing includes a housing 1 made of stainless steel with a rectangular structure; a rectangular box 2 on the top surface of the housing 1 and various sizes of wire-passing holes 14 evenly distributed on the rectangular box 2; the rectangular box 2 is made of aluminum alloy, combining lightweight and structural strength, facilitating the installation and maintenance of the internal mechanisms; the wire-passing holes 14 are compatible with common automotive wire specifications, enabling the positioning of wires of different diameters during wire passing, preventing wire misalignment during the passing process, and improving the positioning accuracy of subsequent processes; the device also integrates a stripping mechanism, a length-fixed mechanism, a sheath-cutting mechanism, and a collection mechanism, realizing integrated processing of automotive wire length fixing, sheath cutting, stripping, and outer sheath collection, significantly improving processing efficiency; and the inner walls of the wire-passing holes 14 are all smoothly polished with a polishing precision of Ra0.8μm to prevent scratching of the wire sheath during the passing process; it also includes: The wire stripping mechanism is located in the middle of the housing 1 and is used to strip the outer sheath of the cut automotive wires. The length-limiting mechanism is located on one side of the rectangular box 2 and is used to limit the length of the automotive wire. The sheathing cutting mechanism is located inside the rectangular box 2 and on one side near the fixed-length mechanism. It is used to perform circumferential cutting on the outer sheath of automotive wires to prepare for the subsequent wire stripping process.

[0019] The collection mechanism is located inside the housing 1 and is used to collect the stripped wire sheaths to prevent them from scattering and accumulating and affecting the operation of the equipment. The length-fixing mechanism includes rectangular plates 4 symmetrically arranged on one side of the rectangular box 2, an upper fixing plate 6 and a lower fixing plate 7 symmetrically arranged between the rectangular plates 4. Various sizes of arc-shaped grooves 29 are evenly opened on the upper fixing plate 6 and the lower fixing plate 7. The specifications of the arc-shaped grooves 29 correspond one-to-one with the wire holes 14 to ensure the coaxiality of the wires with the clamping structure after they are threaded through.

[0020] Both the upper fixed plate 6 and the lower fixed plate 7 are symmetrically provided with miniature electric actuators 5. The fixed end of the miniature electric actuator 5 is fixedly connected to the rectangular plate 4. The miniature electric actuator 5 can drive the upper fixed plate 6 and the lower fixed plate 7 to move towards or away from each other, so as to clamp and release the wires passing through the arc groove 29. The clamping force can be precisely adjusted by the miniature electric actuator 5 to adapt to wire sheaths of different materials and thicknesses, avoiding wire displacement due to excessively loose clamping or damage to the wire core due to excessively tight clamping.

[0021] Each rectangular plate 4 is symmetrically equipped with an electric telescopic rod 13. The fixed end of the electric telescopic rod 13 is set inside the rectangular box 2. The electric telescopic rod 13 can drive the entire rectangular plate 4 and the upper and lower fixed plates to make horizontal linear movements. By adjusting the extension length of the electric telescopic rod 13, the length of the wire extending out of the wire stripping mechanism can be precisely controlled to realize wire stripping operations with different fixed length requirements. The fixed length accuracy is high, and the adjustment operation is convenient. There is no need to replace additional parts, which improves the adaptability and operating efficiency of the device.

[0022] In this invention, the wire stripping mechanism includes a connecting shaft 15 and a connecting shaft 21 symmetrically rotated within a rectangular box 2. Lower wire strippers 19 of different specifications are uniformly fixed to the outer wall of the connecting shaft 15, and multiple upper wire strippers 20 that cooperate with the lower wire strippers 19 are uniformly fixed to the outer wall of the connecting shaft 21. The specifications of the lower wire strippers 19 and the upper wire strippers 20 correspond one-to-one with the wire hole 14 and the arc groove 29, which can realize the stripping of wires of different specifications. The device has strong adaptability.

[0023] In this invention, one end of connecting shaft 15 and connecting shaft 21 extends movably through the rectangular box 2. Gear 28 is fixedly connected to the outer wall of connecting shaft 15, and gear 17 meshes with gear 28 on the outer wall of connecting shaft 21. The meshing transmission between gear 17 and gear 28 ensures that connecting shaft 15 and connecting shaft 21 rotate synchronously in opposite directions, thereby driving the upper wire stripper 20 and the lower wire stripper 19 to rotate synchronously in opposite directions, realizing the rapid stripping of the outer sheath at the cut part of the wire. The stripping efficiency is high, and the traction force on the wire is uniform during the stripping process, avoiding the wire core from being pulled apart.

[0024] In this invention, a pulley 11 is fixedly connected to the outer wall of one end of the connecting shaft 15. A servo motor 12 is installed inside the housing 1. The servo motor 12 provides power to the wire stripping mechanism. Its speed and direction can be precisely adjusted to control the rotation speed of the wire stripping knife assembly, adapting to the wire stripping requirements of different materials. The belt drive method provides smooth transmission, low noise, and high transmission efficiency, ensuring the stable operation of the wire stripping mechanism. At the same time, placing the power source servo motor 12 inside the housing 1 can effectively save external space of the equipment, making the equipment structure more compact. A pulley 10 is fixedly connected to the output shaft of the servo motor 12. A rectangular opening is provided on the top surface of the housing 1. The pulley 10 and the pulley 11 are connected by a belt 9, which passes through the rectangular opening.

[0025] In this invention, a protective shell 8 is provided on the side of the rectangular box 2, and the second pulley 11, the second gear 18 and the first gear 17 are all set inside the protective shell 8. The protective shell 8 can effectively isolate external dust and impurities from entering the transmission structure, avoid wear of transmission components, and improve the service life of the transmission structure. At the same time, it can prevent operators from accidentally touching the rotating transmission components and improve the operational safety of the equipment.

[0026] In this invention, the wire sheathing mechanism includes a linear motor 22 mounted on the top surface of the housing 1 and a slider 23 mounted on the linear motor 22. The linear motor 22 can drive the slider 23 to make precise horizontal linear movements, thereby moving the entire wire sheathing mechanism to cut the wire sheath at different positions and adapt to different wire stripping cutting requirements. An electric telescopic rod 24 is mounted on the bottom surface of the slider 23. The electric telescopic rod 24 can drive the wire sheathing assembly to make vertical lifting movements, thereby realizing the docking and separation of the wire sheathing assembly and the wire, which facilitates the wire threading and adjustment of the cutting position. The movable end of the electric telescopic rod 24 is fixedly connected to a mounting plate 25. A miniature electric push rod 26 is mounted on the bottom surface of the mounting plate 25. The movable end of the miniature electric push rod 26 is fixedly connected to the mounting plate 2. An upper cutting blade 28 is fixedly attached to the bottom surface of mounting plate 25, and a lower cutting blade 27 that cooperates with the upper cutting blade 28 is fixedly attached to the top surface of mounting plate 2. The miniature electric actuator 26 can drive mounting plate 2 to make vertical lifting and lowering movements, thereby adjusting the distance between the lower cutting blade 27 and the upper cutting blade 28, so that the sheathing blade assembly can be adapted to automotive wires of different diameters. The upper cutting blade 28 and the lower cutting blade 27 can cooperate to achieve circumferential cutting of the wire sheath, with a neat cutting surface and precise control of the cutting depth, cutting only the wire sheath without damaging the internal wire core, thus ensuring the performance of the wire.

[0027] In this invention, the collection mechanism includes a discharge port 16 on the top surface of the housing 1. The discharge port 16 is set at the working position of the wire stripping mechanism. The stripped wire sheath can fall directly into the housing 1 through the discharge port 16, realizing rapid discharge of the sheath. A collection box 3 is slidably provided at the bottom of the discharge port 16 via a sliding member. The sliding member includes a slide rail symmetrically arranged at the bottom edge of the discharge port 16. A slide block is slidably provided in the slide rail. The slider 23 is fixed to the outer wall of the collection box 3. The collection box 3 is movably connected to the housing 1 through the sliding cooperation of the slide rail and the slide block. The stripped wire sheath is collected in the collection box 3. When the sheath in the collection box 3 accumulates to a certain amount, the collection box 3 can be directly pulled out from the housing 1 for cleaning and recycling of the sheath. The operation is convenient and can ensure the cleanliness of the inside of the equipment, avoiding the sheath from getting tangled in the equipment parts and causing equipment failure.

[0028] In this invention, a rubber pad 30 is fixedly attached to the inner wall of the arc groove 29. The rubber pad 30 can increase the friction with the outer wall of the wire and improve the stability of the clamping and limiting. On the other hand, it can prevent the hard clamping structure from scratching and damaging the outer sheath of the wire and ensure the integrity of the wire body.

[0029] Working principle: When using this invention, firstly, according to the specifications of the automotive wire to be processed, select the corresponding wire hole 14 and arc groove 29, pass one end of the wire through the wire hole 14 and extend it between the upper fixed plate 6 and the lower fixed plate 7 of the length-fixing mechanism; then, start the micro electric push rod 5 to drive the upper fixed plate 6 and the lower fixed plate 7 to move towards each other, and clamp the wire through the rubber pad 30 in the arc groove 29. Then, according to the length-fixed wire stripping requirements, start the electric telescopic rod 13 to adjust the length of the wire extending to the stripping mechanism to achieve precise length-fixed positioning.

[0030] After the length is fixed, the linear motor 22 is started, which drives the slider 23 and the entire cutting mechanism to move to the position where the wire needs to be cut. Then, the electric telescopic rod 24 is started, which drives the cutting blade assembly to lower to the height where it connects with the wire, so that the wire is between the upper cutting blade 28 and the lower cutting blade 27. The micro electric push rod 26 is started to adjust the distance between the upper cutting blade 28 and the lower cutting blade 27 so that the blades are in contact with the wire sheath and the cutting depth reaches the preset value. Then, the linear motor 22 drives the cutting mechanism to move at a constant speed along the wire axis to achieve circumferential cutting of the wire sheath. After the cutting is completed, the micro electric push rod 26 drives the lower cutting blade 27 to move down, the electric telescopic rod 24 drives the cutting blade assembly to move up and reset, and the linear motor 22 drives the cutting mechanism to move to the initial position. After the insulation is cut, the servo motor 12 is started. The output shaft of the servo motor 12 drives the pulley 10 to rotate, which in turn drives the pulley 11 to rotate through the belt 9. This drives the connecting shaft 15 and the gear 18 to rotate. The gear 18 meshes with the gear 17, which drives the connecting shaft 21 to rotate synchronously in the opposite direction. This causes the upper wire stripper 20 and the lower wire stripper 19 to rotate synchronously in the opposite direction, quickly stripping the insulation of the cut wire.

[0031] The stripped wire sheath falls into the collection box 3 inside the box 1 through the discharge port 16 under the action of gravity, realizing the centralized collection of the sheath; when the sheath in the collection box 3 accumulates to a certain amount, the collection box 3 can be pulled out from the box 1 along the slide rail for cleaning and recycling.

[0032] After stripping the wire, control the miniature electric push rod 5, electric telescopic rod 13, electric telescopic rod 24, and miniature electric push rod 26 to reset in sequence, release the wire, and restore each mechanism to its initial position. This completes one fixed-length wire stripping operation for automotive wires. The above steps can be repeated for continuous processing.

[0033] The above description of the embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fixed-length wire stripping device for automotive wire processing, comprising a housing (1), a rectangular box (2) disposed on the top surface of the housing (1), and various specifications of wire-passing holes (14) uniformly opened on the rectangular box (2), characterized in that, Also includes: The wire stripping mechanism is located in the middle of the housing (1) and is used to strip the automotive wires. A length-limiting mechanism is provided on one side of a rectangular box (2) for limiting the length of automotive wires. A skin-cutting mechanism is disposed inside a rectangular box (2) and close to the side of the fixed-length mechanism; A collection mechanism, which is located inside the box (1), is used to clean the cut skin; The fixed length mechanism includes a rectangular plate (4) symmetrically arranged on one side of the rectangular box (2), an upper fixing plate (6) and a lower fixing plate (7) symmetrically arranged between the rectangular plates (4), and arc grooves (29) of various specifications are evenly opened on the upper fixing plate (6) and the lower fixing plate (7). Both the upper fixed plate (6) and the lower fixed plate (7) are symmetrically provided with a miniature electric actuator (5), and the fixed end of the miniature electric actuator (5) is fixedly connected to the rectangular plate (4); Each of the rectangular plates (4) is symmetrically provided with an electric telescopic rod (13), and the fixed end of the electric telescopic rod (13) is set inside the rectangular box (2).

2. The fixed-length wire stripping device for automotive wire processing according to claim 1, characterized in that, The wire stripping mechanism includes a connecting shaft one (15) and a connecting shaft two (21) symmetrically rotated inside a rectangular box (2). The outer wall of the connecting shaft one (15) is uniformly fixed with lower wire strippers (19) of different specifications. The outer wall of the connecting shaft two (21) is uniformly fixed with multiple upper wire strippers (20) that cooperate with the lower wire strippers (19).

3. The fixed-length wire stripping device for automotive wire processing according to claim 2, characterized in that, One end of the connecting shaft one (15) and the connecting shaft two (21) extends movably through the rectangular box (2). A gear two (18) is fixed on the outer wall of the connecting shaft one (15), and a gear one (17) that meshes with the gear two (18) is provided on the outer wall of the connecting shaft two (21).

4. The fixed-length wire stripping device for automotive wire processing according to claim 3, characterized in that, A pulley 2 (11) is fixedly connected to the outer wall of one end of the connecting shaft 1 (15). A servo motor (12) is installed inside the housing (1). A pulley 1 (10) is fixedly connected to the output shaft of the servo motor (12). A rectangular opening is provided on the top surface of the housing (1). The pulley 1 (10) and the pulley 2 (11) are connected by a belt (9), and the belt (9) passes through the rectangular opening.

5. A fixed-length wire stripping device for automotive wire processing according to claim 4, characterized in that, The rectangular box (2) is provided with a protective shell (8) on its side, and the second pulley (11), the second gear (18) and the first gear (17) are all located inside the protective shell (8).

6. The fixed-length wire stripping device for automotive wire processing according to claim 1, characterized in that, The skin-cutting mechanism includes a linear motor (22) mounted on the top surface of the housing (1) and a slider (23) mounted on the linear motor (22). An electric telescopic rod (24) is mounted on the bottom surface of the slider (23). An installation plate (25) is fixedly connected to the movable end of the electric telescopic rod (24). A miniature electric push rod (26) is mounted on the bottom surface of the installation plate (25). An installation plate (26) is fixedly connected to the movable end of the miniature electric push rod (26). An upper cutting blade (28) is fixedly attached to the bottom surface of the first mounting plate (25), and a lower cutting blade (27) that cooperates with the upper cutting blade (28) is fixedly attached to the top surface of the second mounting plate.

7. A fixed-length wire stripping device for automotive wire processing according to claim 6, characterized in that, The collection mechanism includes a discharge port (16) on the top surface of the box (1), and a collection box (3) is slidably provided at the bottom of the discharge port (16) via a sliding member.

8. The fixed-length wire stripping device for automotive wire processing according to claim 7, characterized in that, The sliding component includes a slide rail symmetrically arranged at the bottom edge of the discharge port (16), a slide block is slidably provided in the slide rail, and the slider is fixed to the outer wall of the collection box (3).

9. A fixed-length wire stripping device for automotive wire processing according to claim 1, characterized in that, A rubber pad (30) is fixed to the inner wall of the arc-shaped groove (29).

Images