Portable rolled-in earphone
By designing a portable rolled headphone structure in the headphones, using components such as cylinder, clamp, sleeve and pressing plate, the problem of easy loosening of the headphone wire during the winding process is solved, and a stable and tight headphone wire winding and efficient winding operation are achieved.
Patent Information
- Application Number
- CN202510108453.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-23
- Publication Date
- 2025-05-02
AI Technical Summary
The existing in-ear headphones are prone to loosening during the winding process, and the headphone cable that has been winded cannot be adjusted to prevent loosening.
A portable roll-in headphone is designed, adopting a structure including a case, headphone cable, earplug, cylinder, clamp, sleeve, sleeve rod, pressing plate, rotating column, control plate and speed control member. By adjusting the position of the pressing plate and the connector, and using the cooperation of the sleeve rod and the clamp, the headphone wire can be stablely curled and adjusted.
The stable winding of the headphone cable is achieved, avoiding the looseness of the headphone cable, and improving the winding efficiency, allowing multiple windings to be closed.
Smart Images

Figure CN119922444A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of earphone structures, in particular to a portable rolled-in earphone. Background Art
[0002] In-ear headphones, also known as in-ear headphones, in-ear earplugs, or in-ear monitors, are headphones used inside the human auditory organ. According to their design, they will seal the user's ear canal when in use.
[0003] Existing in-ear headphones generally have a housing, and the headphone cord is wound by rotating a winding shaft in the housing. However, during the winding process, the headphone cord is easily loosened, and the headphone cord that has been wound in the housing cannot be tightened and adjusted.
[0004] To this end, we propose a portable roll-on earphone. Summary of the invention
[0005] The object of the present invention is to provide a portable roll-on earphone to solve the problems raised in the above background technology.
[0006] To achieve the above object, the present invention provides a portable rolled-in earphone, comprising a housing, an earphone cable wound in the housing, and an earplug;
[0007] The cam is provided with a plurality of sleeves, one of which is movably sleeved with a sleeve rod cooperating with the block, and a movable groove is provided in the casing. A pressure plate is fixed in the casing through the cooperation and insertion of the connecting piece and the movable groove, and a pressure piece is provided at the end of the sleeve rod. When the pressure piece acts on the pressure plate through the sleeve rod, the pressure piece is fixed to the headphone wire of the casing, and a rotating column for limiting the headphone wire is rotatably connected at the edge of the top surface of the casing, a control plate is rotatably connected at the middle part of the top surface of the casing, and a rotating plate is rotatably connected at the middle part of the control plate, and a speed regulating member is provided between the rotating plate and the cylinder, and the speed regulating member is used to rotate the control plate to make the sleeve rotate quickly, and the rotating plate rotating in a circle contacts and acts on the rotating column to make the rotating column rotate, thereby moving the headphone wire.
[0008] Preferably, the pressure plate has an arc-shaped structure, and inclined surfaces are provided at both ends of the pressure plate. Elastic layers are fixedly connected to both ends of the pressure plate. A card plate that slides with the headphone wire is fixedly connected inside the casing, and the elastic layer is pressed and fixed to the headphone wire located in the card plate.
[0009] Preferably, the end of the sleeve rod that presses against and contacts the block is in a truncated cone-shaped structure, so that the insertion is smooth.
[0010] Preferably, the clamping block is provided with a plurality of clamping grooves which are pressed and matched with the end of the sleeve rod, and the depths of the plurality of clamping grooves increase progressively.
[0011] Preferably, the connecting member includes two sliding rods connected and fixed to the pressure plate, the bottom of the sliding rods slidingly cooperates with the movable groove, the top of the cross-section of the movable groove is in an inverted trapezoidal shape, a threaded rod is threadedly connected to the middle of the pressure plate, the bottom of the threaded rod passes through the pressure plate and is fixedly connected to an extrusion disk plugged and fixed to the movable groove, the extrusion disk is an elastic extrusion disk, and a control member is provided on the top of the threaded rod.
[0012] Preferably, the control member comprises a connecting plate fixedly connected to the top of the threaded rod, the end of the connecting plate is fixedly connected to a pressing rod, and the rotating pressing rod is in pressing contact with the edge of the casing.
[0013] Preferably, a limiting column is fixedly connected to the sleeve, and the limiting column and the rotating column are used to limit the wound headphone wire.
[0014] Preferably, the pressing member includes an elastic plate which is fixedly connected to the sleeve rod and is distributed in an inclined manner, and an inclined pressure plate is fixedly connected to the top of the elastic plate. The end of the sleeve rod away from the blocking block is a hollow structure, and the sleeve rod is movably connected to a contact column which is pressed and matched with the pressing plate through a compression spring, and the inclined pressure plate presses against the headphone wire located in the casing.
[0015] Preferably, a rectangular groove is formed at the top of the rotating column, a pressing cap is movably inserted at the bottom of the rectangular groove, and a compression spring is provided between the pressing cap and the rectangular groove.
[0016] Compared with the prior art, the present invention has the following beneficial effects:
[0017] The headphone wire close to the earplug or the headphone wire close to the plug rod can be selectively rolled up. When one end needs to be rolled up, the pressing plate is moved close to the corresponding card plate, and the pressing plate is fixed at the position by the connecting member; the control plate is rotated to roll up the headphone wire inside the housing, and when the sleeve rod passes through the pressing plate, the gap of the pressing member presses the rolled headphone wire inside the housing to prevent the headphone wire from loosening;
[0018] The control plate continues to rotate, so that the headphone cable continues to be wound, thereby ensuring that the headphone cable is wound stably and tightly; in the present application, a speed regulating member is also used to rotate the control plate at a small angle, so that the effect of winding multiple circles can be achieved, thereby improving the winding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a schematic diagram of the overall structure of the present invention;
[0020] Figure 2 It is a schematic diagram of the casing structure of the present invention;
[0021] Figure 3 It is a schematic diagram of the cross-sectional structure of the casing of the present invention;
[0022] Figure 4 This is a schematic diagram of the housing disassembly structure of the present invention;
[0023] Figure 5 It is a schematic diagram of the split structure of the inner gear ring and the third gear of the present invention;
[0024] Figure 6 It is a schematic cross-sectional structure diagram of the first gear, the second gear and the third gear of the present invention;
[0025] Figure 7 It is a schematic diagram of the matching structure of the first gear, the second gear and the third gear and the cylinder of the present invention;
[0026] Figure 8 It is a schematic diagram of the matching structure of the first gear, the second gear and the third gear with the internal gear ring of the present invention;
[0027] Fig. 9 It is a schematic diagram of the split structure of the control member and the pressure plate of the present invention;
[0028] Fig.10 It is a schematic diagram of the split structure of the cylinder and the block of the present invention;
[0029] Fig.11 It is a schematic diagram of the matching structure of the cylinder and the clamping block of the present invention;
[0030] Fig.12 It is a schematic cross-sectional structure diagram of the pressure plate and the housing of the present invention;
[0031] Fig.13 For the present invention Fig.12 Schematic diagram of the structure splitting;
[0032] Fig.14 It is a schematic diagram of the matching structure of the clamping block, the sleeve rod and the pressure plate of the present invention;
[0033] Fig.15 It is a schematic diagram of the disassembled structure of the clamping block, the sleeve rod and the pressure plate of the present invention.
[0034] In the figure: 1. casing; 2. earphone cable; 3. earplug; 4. barrel; 5. block; 6. sleeve; 7. sleeve rod; 8. movable groove; 9. pressure plate; 10. rotating column; 11. control board; 12. rotating plate; 13. elastic layer; 14. card plate; 15. card slot; 16. slide rod; 17. threaded rod; 18. extrusion disk; 19. connecting plate; 20. pressure rod; 21. limit column; 22. elastic plate; 23. inclined pressure plate; 24. contact column; 25. rectangular groove; 26. pressure cap; 27. rotating shaft; 28. inner gear ring; 29. first gear; 30. second gear; 31. third gear; 32. winding shaft; 33. compression spring. DETAILED DESCRIPTION
[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0036] See also Figure 1-Figure 15 The present invention provides a portable rolled-in earphone, comprising a housing 1, an earphone wire 2 wound in the housing 1, and an earplug 3, wherein the other end of the earphone wire 2 is provided with an insertion rod, and the insertion rod is inserted into a jack in a mobile phone or a radio;
[0037] The present invention also comprises: a connecting member and a cylinder body 4 rotatably connected to the middle part of the casing 1, a block 5 movably matched with the casing 1 and rotatably connected is arranged in the cylinder body 4, a plurality of sleeves 6 are fixedly connected to the outer surface of the cylinder body 4, a sleeve rod 7 matched with the block 5 is movably sleeved in one of the sleeves 6, a movable groove 8 is opened in the casing 1, a pressing plate 9 is fixed in the casing 1 through the matching insertion of the connecting member and the movable groove 8, a pressing member is arranged at the end of the sleeve rod 7, when the pressing member acts on the pressing plate 9 through the sleeve rod 7, the pressing member is fixed to the earphone line 2 of the casing 1, a rotating column 10 for limiting the earphone line 2 is rotatably connected at the edge of the top surface of the cylinder body 4, a control board 11 is rotatably connected to the middle part of the top surface of the casing 1, a rotating plate 12 is rotatably connected to the middle part of the control board 11, a speed regulating member is arranged between the rotating plate 12 and the cylinder body 4, the speed regulating member is used to rotate the control board 11 to make the sleeve 6 rotate quickly, the rotating plate 12 rotating in a circle contacts and acts on the rotating column 10, so that the rotating column 10 rotates, thereby moving the earphone line 2;
[0038] In the present application, the earphone cable 2 close to the earplug 3 or the earphone cable 2 close to the plug rod can be selectively rolled up. When one end needs to be rolled up, the pressing plate 9 is moved close to the corresponding card plate 14, and the pressing plate 9 is fixed at the position by the connecting member;
[0039] The control plate 11 is rotated to reel the earphone cord 2 in the housing 1. When the sleeve rod 7 passes through the pressing plate 9, the gap of the pressing member presses the reeled earphone cord 2 in the housing 1 to prevent the earphone cord 2 from loosening.
[0040] The control panel 11 continues to rotate, so that the earphone cord 2 continues to be wound, thereby ensuring that the earphone cord 2 is wound stably and tightly;
[0041] In the present application, a speed regulating member is used to rotate the control panel 11 by a small angle, so that the effect of winding multiple circles can be achieved, thereby improving the winding efficiency.
[0042] The pressing plate 9 is an arc-shaped structure, and inclined surfaces are provided at both ends of the pressing plate 9. The two ends of the pressing plate 9 are fixedly connected with elastic layers 13. A card plate 14 that slides with the earphone wire 2 is fixedly connected inside the housing 1. The elastic layer 13 is pressed and fixed with the earphone wire 2 located in the card plate 14. By making the two ends of the pressing plate 9 at an inclined angle, it is convenient for the contact column 24 to slide smoothly with the pressing plate 9, so that the end of the sleeve rod 7 is inserted into the slot 15 of the card block 5. When the contact column 24 slides along the pressing plate 9, the sleeve rod 7 is always pressed in the slot 15 of the card block 5, thereby driving the card block 5 to rotate synchronously. When the contact column 24 is separated from the pressing plate 9, the sleeve rod 7 is separated from the slot 15 of the card block 5 (under the centrifugal effect, the contact column 24 is made of a high-density material);
[0043] When it is necessary to fix the headphone cord 2 on the clamping plate 14 at one end to ensure that the other end is reeled in, the elastic layer 13 at the end of the pressing plate 9 is pressed against the clamping plate 14 by moving the pressing plate 9, and the control member is rotated to fix the pressing plate 9 firmly at the position, ensuring that the elastic layer 13 and the clamping plate 14 tightly restrict the headphone cord 2, so that the other end of the headphone cord 2 is easy to reel in, and the headphone cord 2 can move adaptively in the housing 1.
[0044] One end of the sleeve rod 7 that contacts the clamping block 5 is in a truncated cone structure, which is convenient for pressing against the V-shaped clamping groove 15, and the clamping block 5 is driven to rotate synchronously by a certain angle through the rotating sleeve rod 7.
[0045] The block 5 is provided with a plurality of slots 15 for pressing and fitting with the end of the sleeve rod 7. The depths of the plurality of slots 15 are progressively increased. The middle axis of the bottom of the block 5 rotates with the housing 1, and the bottom surface of the block 5 has a certain friction with the housing 1. When the end of the sleeve rod 7 does not act on the block 5, the block 5 does not actively rotate relative to the housing 1.
[0046] It is worth noting that: the depth of the card slot 15 is set differently, and the rotation of the gap of the card block 5 cooperates with the winding of the headphone cord 2. When the deeper card slot 15 corresponds to the position of the sleeve rod 7, the contact column 24 presses on the pressing plate 9. Under the action of the compression spring, the movement of the sleeve rod 7 is increased, and the sleeve rod 7 is pressed in the deeper card slot 15, that is, the sleeve rod 7 moves a long distance (the movement distance in the direction close to the card block 5 is large), so that the elastic plate 22 and the inclined pressure plate 23 move a long distance. The moving distances of the elastic plate 22 and the inclined pressure plate 23 are adaptively adjusted according to the amount of the wound headphone cord 2, thereby ensuring that the inclined pressure plate 23 presses the headphone cord 2 tightly, thereby increasing the applicability of use.
[0047] The connecting member includes two slide bars 16 connected and fixed to the pressure plate 9, the bottom of the slide bar 16 is slidably matched with the movable groove 8, the top of the cross section of the movable groove 8 is in an inverted trapezoidal shape, the middle of the pressure plate 9 is threadedly connected with a threaded rod 17, the bottom of the threaded rod 17 passes through the pressure plate 9 and is fixedly connected with an extrusion disk 18 plugged and fixed with the movable groove 8, the extrusion disk 18 is an elastic extrusion disk 18, and a control member is provided on the top of the threaded rod 17;
[0048] The two slide bars 16 are moved along the movable groove 8 by the movable pressing plate 9, and the slide bars 16 will not be separated from the movable groove 8, so that the position of the pressing plate 9 is moved, and the elastic layer 13 at the end of the pressing plate 9 is in contact with one of the clamping plates 14, and the threaded rod 17 is rotated by the control member to drive the extrusion plate 18 to move downward, so that the elastic extrusion plate 18 is clamped into the movable groove 8, and the pressing plate 9 is fixed, so that the elastic layer 13 cooperates with the clamping plate 14 to press the earphone wire 2 located in the clamping plate 14, so that the rolled earphone wire 2 can be tightened and prevented from being loosened;
[0049] The housing 1 may be provided with a through hole connected to the movable groove 8 to prevent dust, paper scraps, etc. from accumulating in the movable groove 8 and facilitate cleaning.
[0050] The control component includes a connecting plate 19 fixedly connected to the top of the threaded rod 17, and a pressure rod 20 is fixedly connected to the end of the connecting plate 19. The rotating pressure rod 20 is in pressure contact with the edge of the casing 1. After the position of the pressure plate 9 is adjusted by movement, the pressure rod 20 is rotated to make the pressure rod 20 close to the edge of the casing 1, thereby driving the connecting plate 19 to rotate. The rotating connecting plate 19 causes the threaded rod 17 to rotate, thereby moving downward along the pressure plate 9, driving the extrusion plate 18 to move downward, so that the elastic extrusion plate 18 is stably stuck in the movable groove 8, thereby completing the fixation of the position of the pressure plate 9.
[0051] The sleeve 6 is fixedly connected to a limiting post 21 , and the limiting post 21 and the rotating post 10 are used to limit the wound headphone cord 2 . Through the distribution of the rotating post 10 and the limiting post 21 , the wound headphone cord 2 is spiraled in an orderly manner, reducing the messy arrangement of the headphone cord 2 .
[0052] The pressing member includes an elastic plate 22 which is connected and fixed to the sleeve rod 7 and is distributed in an inclined manner. An inclined pressure plate 23 is fixedly connected to the top of the elastic plate 22. The end of the sleeve rod 7 away from the block 5 is a hollow structure. The sleeve rod 7 is movably sleeved with a contact column 24 which is pressed and matched with the pressing plate 9 through a compression spring. The inclined pressure plate 23 presses against the earphone wire 2 located in the housing 1. When the contact column 24 in the sleeve rod 7 contacts the pressing plate 9, the contact column 24 moves along the sleeve 6 under the action of the pressing plate 9, the compression spring contracts, and the elastic plate 22 moves with the sleeve rod 7, driving the inclined pressure plate 23 to move, thereby pressing the earphone wire 2 located at the inner edge of the housing 1. At this time, the control board 11 continues to rotate and rewind, so that the rewound earphone wire 2 in the middle of the housing 1 is slightly tightened to prevent the earphone wire 2 in the middle of the housing 1 from being rewound and loosened.
[0053] The present application uses a pressure piece that operates in a gap to adjust and tighten the wound headphone wire 2 in a gap, thereby preventing the wound headphone wire 2 from becoming loose.
[0054] The top of the rotating column 10 is provided with a rectangular groove 25, and a pressing cap 26 is movably inserted at the bottom of the rectangular groove 25. A compression spring 33 is provided between the pressing cap 26 and the rectangular groove 25. When the third gear 31 that makes a circular motion and rotates passes the pressing cap 26 on the rotating column 10, the latch teeth of the third gear 31 first contact the edge of the pressing cap 26, and then the bottom surface of the third gear 31 contacts the top of the pressing cap 26. The bottom of the rotating third gear 31 acts on the top of the pressing cap 26, on the one hand, so that the pressing cap 26 moves downward along the rotating column 10, and on the other hand, the pressing cap 26 drives the rotating column 10 to rotate, so that the rotating rotating column 10 can movably contact the earphone wire 2 on the rotating column 10, so as to avoid the earphone wire 2 being pulled too tight inside, which is not convenient for winding up the earphone wire 2 and is also easy to cause damage to the earphone wire 2. Among them, the outer surface of the pressing cap 26 is provided with a rubber wear-resistant layer to ensure that the pressing cap 26 rotates under the action of the third gear 31.
[0055] It is worth noting that the speed regulating member in the present application includes a self-rotating shaft 27 that penetrates into the housing 1 and is connected and fixed to the rotating plate 12, an inner gear ring 28 is fixedly connected to the housing 1, a first gear 29, a second gear 30 and a third gear 31 that are rotatably connected to the rotating plate 12 and mesh with each other, the first gear 29 meshes with the inner gear ring 28, a winding shaft 32 is fixedly connected between the third gear 31 and the cylinder 4, and the third gear 31 is rotatably matched with the pressing cap 26;
[0056] The headphone cable 2 is wound up by rotating the control plate 11. When the control plate 11 rotates, the rotating plate 12 is driven to rotate synchronously through the rotating shaft 27, so that the third gear 31 makes a circular motion. Due to the action of the fixed inner gear ring 28, the third gear 31 that makes a circular motion rolls along the inner gear ring 28, and the third gear 31 quickly rotates on the rotating plate 12. The third gear 31 drives the second gear 30 and the first gear 29 to rotate in turn. The rotation of the first gear 29 drives the winding shaft 32, the cylinder 4 and the sleeve 6 to rotate quickly, so that the headphone cable 2 can be quickly wound up by rotating the control plate 11 at a small angle;
[0057] Furthermore, since the pitch circle radius of the first gear 29 is smaller than the pitch circle radius of the second gear 30, and the pitch circle radius of the second gear 30 is smaller than the pitch circle radius of the third gear 31, the efficiency of winding up the headphone cord 2 is further accelerated, avoiding the need to rotate the control panel 11 multiple times for fast winding, thereby avoiding inconvenience in operation.
[0058] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A portable roll-on earphone, comprising: A housing (1), an earphone cable (2) wound inside the housing (1), and an earplug (3); The invention is characterized in that it also includes: a connecting piece and a cylinder (4) rotatably connected to the middle part of the housing (1), a block (5) movably matched with the housing (1) is provided in the cylinder (4), and a plurality of sleeves (6) are fixedly connected to the outer surface of the cylinder (4), and a sleeve rod (7) matched with the block (5) is movably sleeved in one of the sleeves (6), and a movable groove (8) is provided in the housing (1), and a pressure plate (9) is fixed in the housing (1) through the matching insertion of the connecting piece and the movable groove (8), and a pressure piece is provided at the end of the sleeve rod (7), and when the pressure piece acts on the pressure plate (9) through the sleeve rod (7), the pressure piece is pressed. ), the pressing member is fixed to the earphone wire (2) of the housing (1), a rotating column (10) for limiting the earphone wire (2) is rotatably connected at the edge of the top surface of the cylinder (4), a control panel (11) is rotatably connected in the middle of the top surface of the housing (1), a rotating plate (12) is rotatably connected in the middle of the control panel (11), a speed regulating member is provided between the rotating plate (12) and the cylinder (4), the speed regulating member is used to rotate the control panel (11) to make the sleeve (6) rotate rapidly, the rotating plate (12) rotating in a circle contacts and acts on the rotating column (10), so that the rotating column (10) rotates, thereby moving the earphone wire (2).
2. A portable roll-on earphone according to claim 1, characterized in that: The pressing plate (9) is of an arc-shaped structure, and inclined surfaces are arranged at both ends of the pressing plate (9). The two ends of the pressing plate (9) are fixedly connected with elastic layers (13). A card plate (14) that is slidably matched with the headphone wire (2) is fixedly connected inside the housing (1), and the elastic layer (13) is pressed and fixed with the headphone wire (2) located inside the card plate (14).
3. A portable roll-on earphone according to claim 2, characterized in that: One end of the sleeve rod (7) that presses against and contacts the clamping block (5) is in a truncated cone-shaped structure.
4. The portable roll-on earphone according to claim 1, characterized in that: The clamping block (5) is provided with a plurality of clamping grooves (15) which are pressed and matched with the end of the sleeve rod (7), and the depths of the plurality of clamping grooves (15) increase progressively.
5. The portable roll-on earphone according to claim 1, characterized in that: The connecting member comprises two sliding rods (16) connected and fixed to the pressure plate (9); the bottom of the sliding rod (16) is slidably matched with the movable groove (8); the top of the cross section of the movable groove (8) is in an inverted trapezoidal shape; a threaded rod (17) is threadedly connected to the middle of the pressure plate (9); the bottom of the threaded rod (17) passes through the pressure plate (9) and is fixedly connected to an extrusion disk (18) plugged and fixed to the movable groove (8); the extrusion disk (18) is an elastic extrusion disk (18); and a control member is provided at the top of the threaded rod (17).
6. The portable roll-on earphone according to claim 5, characterized in that: The control member comprises a connecting plate (19) fixedly connected to the top of the threaded rod (17); a pressing rod (20) is fixedly connected to the end of the connecting plate (19); the rotating pressing rod (20) is in pressing contact with the edge of the housing (1).
7. The portable roll-on earphone according to claim 1, characterized in that: The sleeve (6) is fixedly connected to a limiting column (21), and the limiting column (21) and the rotating column (10) are used to limit the wound headphone wire (2).
8. The portable roll-on earphone according to claim 1, characterized in that: The pressing member comprises an elastic plate (22) which is connected and fixed to the sleeve rod (7) and is distributed in an inclined manner. The top of the elastic plate (22) is fixedly connected with an inclined pressure plate (23). The end of the sleeve rod (7) away from the block (5) is a hollow structure. The sleeve rod (7) is movably connected to a contact column (24) which is pressed and matched with the pressing plate (9) through a compression spring. The inclined pressure plate (23) presses against the headphone wire (2) located in the housing (1).
9. The portable roll-on earphone according to claim 1, characterized in that: A rectangular groove (25) is provided on the top of the rotating column (10), a pressing cap (26) is movably inserted into the bottom of the rectangular groove (25), and a compression spring (33) is provided between the pressing cap (26) and the rectangular groove (25).