Hinge structure of door frame

Abstract

The utility model belongs to the technical field of hinges, and particularly relates to a hinge structure of a door frame, which comprises a connecting seat and a mounting seat which are rotatably connected, a fixing seat connected with a door body or the door frame is detachably arranged on the mounting seat, a containing cavity is arranged on the fixing seat, the mounting seat is arranged in the containing cavity in a penetrating manner, a hinge arm is arranged on the connecting seat, and the hinge arm is connected with the door body or the door frame. The hinge arm extends into the storage cavity and is rotationally connected with the mounting base through a hinge rod, and a supporting bottom plate is arranged at the bottom of the storage cavity; the end portion of the containing cavity extends towards the side face to form a fixing plate, a fixing hole is formed in the fixing plate, a mounting plate is arranged on the mounting seat, and the fastener penetrates through the mounting plate and is connected with the fixing hole, so that the fixing seat and the mounting seat are relatively fixed, and the hinge structure of the door frame is stable in mounting and convenient to mount.

Description

Technical Field

[0001] The utility model belongs to the technical field of hinges, and particularly relates to a hinge structure of a door frame. Background Art

[0002] A hinge, also known as a hinge, is a mechanical device used to connect two solid bodies and allow relative rotation between them. It is often used to install doors and windows.

[0003] Most traditional hinges include two rotatably connected fixed plates, which are respectively fixed to the surface of the door frame and the door panel. In order to facilitate the stable installation of the hinges, many hinges on the market are now embedded in the door body and the door frame. For example, Chinese invention patent application CN202311402387.9 discloses an invisible hinge for an aluminum alloy swing door and a method of using the same, which includes a swing door frame material and a swing door leaf material, and an installation groove is provided on one side surface of the swing door frame material. The invisible hinge of the aluminum alloy casement door and the use method thereof are mainly composed of three parts: a hinge leaf material base, a hinge frame material base and a hinge center axis. During installation, the hinge frame material base and the casement door frame material are connected by hinge frame material screws and nut sleeves to play a fixing role. The hinge leaf material base and the casement door leaf material are fixed by connecting the hinge leaf material screws and the hinge leaf material base, thereby achieving the effect of opening and closing. The invisible hinge structure is scientific and reasonable, and has the advantages of reliable structure, tight assembly, and flexible and light operation. In addition, it solves the disadvantage of the conventional externally exposed hinge that the color of the hinge is inconsistent with the color of the casement door profile.

[0004] The hinge frame material bases are respectively fixed on the side surfaces of the casement door frame material. After long-term use, the hinges are prone to droop, thereby affecting the connection and cooperation between the door panel and the door frame, and affecting the normal use of the user. Summary of the invention

[0005] In order to overcome the defects in the prior art, the purpose of the utility model is to provide a hinge structure of a door frame which is stable and easy to install.

[0006] The purpose of the utility model is achieved in this way:

[0007] A hinge structure for a door frame comprises a connecting seat and a mounting seat which are rotatably connected. The mounting seat is detachably provided with a fixing seat connected to a door body or a door frame. The fixing seat is provided with a storage cavity. The mounting seat is passed through the storage cavity. A hinge arm is provided on the connecting seat. The hinge arm extends into the storage cavity and is rotatably connected to the mounting seat through a hinge rod. A supporting base plate is provided at the bottom of the storage cavity. The end of the storage cavity extends laterally to form a fixing plate. A fixing hole is provided on the fixing plate. A mounting plate is provided on the mounting seat. A fastener passes through the mounting plate and is connected to the fixing hole, so that the fixing seat and the mounting seat are relatively fixed.

[0008] The utility model is further configured as follows: a positioning protrusion is provided on one side of the mounting plate close to the fixed plate, and a positioning groove adapted to the door body or door frame is formed between the outer periphery of the positioning protrusion and the fixed plate; the control fastener fixes the fixed seat and the mounting seat relatively, and makes the two side walls of the positioning groove respectively press against the door body or door frame.

[0009] The utility model is further configured as follows: the fixing plate extends toward the end of the hinged rod to form a support plate, the support plate extends along the axial direction of the hinged rod, and a support portion for supporting the mounting seat is arranged on the support plate.

[0010] The utility model is further configured as follows: the articulated arm includes an extension section extending into the storage cavity and a mounting section detachably arranged on the connecting seat, the extension section and the mounting section are detachably connected by a fastener, and a hook groove and a fixing groove are arranged on the mounting section, and one end of the hook groove is inclined downward and extends to one side of the mounting section.

[0011] The utility model is further configured as follows: one end of the fixing groove is inclined upward and extends to one side of the installation section, and the hook groove and the fixing groove are configured in a V shape.

[0012] The utility model is further configured as follows: an adjustment slot is provided in the connecting seat, an opening is provided on one side of the adjustment slot, one end of the articulated arm passes through the opening and is connected to the mounting seat; a plurality of adjustment rods are rotatably provided in the adjustment slot, a driving thread is provided on the adjustment rod, and an adjustment plate is provided in the adjustment slot, the articulated arm is mounted on the adjustment plate, and threaded holes adapted to the driving threads are provided on the adjustment plate; the rotation of the adjustment rod is controlled, and the driving thread drives the adjustment plate to move relative to the adjustment slot, and adjusts the relative position of the articulated arm and the connecting seat.

[0013] The utility model is further configured as follows: a pressure plate is detachably provided on the adjustment plate through fasteners, a mounting portion is provided on the hinged arm, the pressure plate presses the mounting portion against the adjustment plate, and the mounting portion and the adjustment plate are relatively fixed, and anti-slip grooves are provided on the end surfaces of the mounting portion that contact the adjustment plate and the pressure plate.

[0014] The utility model is further configured as follows: a mounting groove is provided on the mounting portion, a fastener passes through the pressure plate and the mounting groove and is connected to the adjustment plate, and the relative position of the fastener in the mounting groove is adjusted to thereby adjust the relative position of the articulated arm and the adjustment plate.

[0015] The utility model is further configured as follows: the articulated arm comprises an articulated portion sleeved on the articulated rod, support bearings are arranged at both ends of the articulated portion, and the support bearings are sleeved on the articulated rod.

[0016] Compared with the prior art, the utility model has the following advantages:

[0017] 1. In the utility model, the mounting seat is installed and supported by the storage cavity on the fixing seat, which is beneficial to dispersing the force of the mounting seat and the door frame or door panel, and is beneficial to dispersing the force of the door panel or door frame to avoid damage to the door panel or door frame. During installation, the fixing seat can be first embedded in the door frame or door panel, and then the mounting seat is connected to the fixing seat, which is convenient for the relative installation of the door panel and the door frame. When the door panel and the door frame are relatively disassembled, there is no need to relatively disassemble the hinge and the door panel or door frame, which is convenient for repeated disassembly and assembly of the door panel and the door frame, and convenient for users to repeatedly disassemble and assemble the door panel.

[0018] 2. In the utility model, a positioning groove is formed by the positioning protrusion and the fixing plate, and the structure is simple. It is convenient for the positioning connection between the hinge and the door panel or door frame, and the fixed installation of the hinge is convenient. It can also avoid the relative deviation and misalignment between the hinge and the door panel or door frame during use or installation, and it is convenient for the use of the hinge. The setting of the support plate is conducive to providing stronger support for the mounting seat, avoiding the deformation of the fixing plate under force and causing the connecting seat to sag, which is conducive to the stable installation of the door frame and door panel.

[0019] 3. The detachably connected extension section and installation section in the utility model facilitate the quick connection and cooperation between the articulated arm and the installation seat and the connecting seat, and facilitate the assembly of the hinge. The setting of the hook groove allows the fastener to be pre-installed with the installation section, and then the hook groove is hung on the fastener. Finally, the extension section and the installation section are stably installed, which is convenient for the user to connect the hinge to the door panel and the door frame respectively, and is convenient for the user to use; the V-shaped hook groove and fixing groove facilitate the normal and reverse installation of the hinge, which is convenient for the user to use flexibly.

[0020] 4. In the utility model, the relative position of the adjustment plate on the connecting seat is adjusted by the driving thread on the adjusting rod, so that the user can adjust the relative position of the articulated arm and the connecting seat according to the needs; the setting of the pressure plate and the anti-slip groove facilitates the installation and disassembly of the articulated arm and the adjustment plate, and the assembly of the hinge; the setting of the installation groove can further increase the flexibility of the installation of the articulated arm on the connecting seat, and facilitate the flexible adjustment of the relative position of the connecting seat and the mounting seat.

[0021] 5. The support bearing in the utility model is provided to facilitate the flexible rotation of the hinge arm and the mounting seat, reduce the wear of the hinge arm and the mounting seat during use, help to extend the service life of the hinge, and reduce the noise during the use of the hinge. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the utility model;

[0023] Figure 2 It is a usage state diagram of the utility model;

[0024] Figure 3 It is a structural schematic diagram of the connection structure of the mounting seat, the fixing seat and the extension section in the utility model;

[0025] Figure 4 It is an exploded schematic diagram of the connection structure of the mounting seat, the fixing seat and the extension section in the utility model;

[0026] Figure 5 It is a structural schematic diagram of the mounting seat in the utility model;

[0027] Figure 6 It is a structural schematic diagram of the end cover in the utility model;

[0028] Figure 7 It is a cross-sectional view of the connection structure between the connection seat and the installation section in the utility model;

[0029] Figure 8 It is an exploded schematic diagram of the connection structure between the connection seat and the installation section in the utility model;

[0030] Fig. 9 It is a cross-sectional view of the connection structure between the adjustment plate and the connection seat in the utility model;

[0031] Fig.10 It is a cross-sectional view of the adjustment rod in the utility model;

[0032] Fig.11 It is a structural schematic diagram of the installation section in the utility model.

[0033] Meanings of the numbers in the figure: 1-mounting seat; 11-mounting plate; 12-through hole; 13-hinge plate; 14-hinge rod; 15-positioning protrusion; 16-positioning groove; 2-connecting seat; 21-panel; 22-housing; 24-adjusting rod; 221-first shell; 222-second shell; 223-adjusting groove; 224-rotation hole; 225-hinge protrusion; 226-first control port; 227-movable groove; 228-second control port; 2211-opening; 241-rotation protrusion; 242-driving hole; 243-hinge hole; 244-driving thread; 3-fixed seat; 31-end cover; 32-cover; 311-support plate; 312-support part; 313-notch; 314-fixed plate; 321-storage cavity;

[0034] 322-support base plate; 323-fixing hole; 4-articulated arm; 41-extension section; 42-installation section; 411-hinge portion; 412-connecting hole; 421-hook groove; 422-fixing groove; 423-installation portion; 424-installation groove; 425-anti-slip groove; 5-adjustment plate; 51-threaded hole; 6-pressure plate; 7-support bearing; 8-fastener. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments:

[0036] See also Figures 1 to 11As shown, a hinge structure of a door frame comprises a connecting seat 2 and a mounting seat 1 which are rotatably connected, the mounting seat 1 being detachably provided with a fixing seat 3 connected to a door body or a door frame, the fixing seat 3 being provided with a receiving cavity 321, the mounting seat 1 being inserted into the receiving cavity 321, the connecting seat 2 being provided with a hinge arm 4, the hinge arm 4 extending into the receiving cavity 321, and being rotatably connected to the mounting seat 1 through a hinge rod 14, and a supporting bottom plate 322 being provided at the bottom of the receiving cavity 321; the end of the receiving cavity 321 extending laterally to form a fixing plate 314, the fixing plate 314 being provided with a fixing hole 323, the mounting seat 1 being provided with a mounting plate 11, and the mounting plate 11 being provided with a fixing hole 324; A through hole 12 is provided, and a fastener 8 passes through the through hole 12 and is connected to the fixing hole 323, so that the fixing seat 3 and the mounting seat 1 are relatively fixed. In this structure, the mounting seat 1 is installed and supported by the storage cavity 321 on the fixing seat 3, which is beneficial to dispersing the force of the mounting seat 1 and the door frame or door panel, and is beneficial to dispersing the force of the door panel or door frame to avoid damage to the door panel or door frame. During installation, the fixing seat 3 can be first embedded in the door frame or door panel, and then the mounting seat 1 is connected to the fixing seat 3, which is convenient for the relative installation of the door panel and the door frame. When the door panel and the door frame are relatively disassembled, there is no need to disassemble the hinge and the door panel or door frame relatively, which is convenient for repeated disassembly and assembly of the door panel and the door frame, and convenient for users to repeatedly disassemble and assemble the door panel.

[0037] The articulated arm 4 described in the utility model includes an articulated portion 411 sleeved on the articulated rod 14, and support bearings 7 are arranged at both ends of the articulated portion 411. The support bearings 7 are sleeved on the articulated rod 14. The arrangement of the support bearings 7 facilitates the flexible rotation of the articulated arm 4 and the mounting seat 1, reduces the wear of the articulated arm 4 and the mounting seat 1 during use, is beneficial to prolonging the service life of the hinge, and reduces the noise during the use of the hinge.

[0038] The fixing plate 314 extends toward the end of the hinge rod 14 to form a support plate 311. The support plate 311 extends along the axial direction of the hinge rod 14, and a support portion 312 for supporting the mounting seat 1 is provided on the support plate 311. The provision of the support plate 311 is beneficial for providing stronger support for the mounting seat 1, avoiding the fixing plate 314 from being deformed by force and causing the connecting seat 2 to sag, which is beneficial for the stable installation of the door frame and the door panel.

[0039] The fixing seat 3 in this embodiment includes a detachably connected end cover 31 and a cover 32, a storage cavity 321 is arranged in the cover 32, the end cover 31 is arranged at the end of the cover 32 and is used to be installed on the door panel or the side wall of the door frame, the support plate 311 and the support part 312 are both arranged on the end cover 31, and a notch 313 is arranged on the end cover 31, the hinge arm 4 passes through the notch 313 and is connected to the connecting seat 2, and the mounting seat 1 extends into the storage cavity 321 to form two hinge plates 13, and the hinge rod 14 is arranged between the two hinge plates 13.

[0040] Most of the door panels and door frames on the market now are made of aluminum profiles, and a fixing groove 422 for installing the fixing seat 3 and the connecting seat 2 is opened on the side of the aluminum profile. Preferably, the mounting plate 11 is provided with a positioning protrusion 15 close to the fixing plate 314, and a positioning groove 16 adapted to the door body or door frame is formed between the outer periphery of the positioning protrusion 15 and the fixing plate 314; the control fastener 8 fixes the fixing seat 3 and the mounting seat 1 relatively, and makes the two side walls of the positioning groove 16 respectively press against the door body or door frame. The positioning groove 16 is formed by the positioning protrusion 15 and the fixing plate 314 in this structure, and the structure is simple, which is convenient for the positioning connection between the hinge and the door panel or door frame, and the fixed installation of the hinge is convenient, and the relative deflection and dislocation of the hinge and the door panel or door frame during use or installation can be avoided, which is convenient for the use of the hinge. In this embodiment, the two side walls of the positioning groove 16 are respectively pressed against the two ends of the fixing groove 422.

[0041] The articulated arm 4 includes an extension section 41 extending into the storage cavity 321 and a mounting section 42 detachably arranged on the connecting seat 2. The extension section 41 and the mounting section 42 are detachably connected by a fastener 8. A hook groove 421 and a fixing groove 422 are arranged on the mounting section 42. One end of the hook groove 421 is tilted downward and extends to one side of the mounting section 42. The detachably connected extension section 41 and the mounting section 42 facilitate the quick connection and cooperation between the articulated arm 4 and the mounting seat 1 and the connecting seat 2, and facilitate the assembly of the hinge. The setting of the hook groove 421 allows the fastener 8 to be pre-installed with the mounting section 42, and then the hook groove 421 is hung on the fastener 8. Finally, the extension section 41 and the mounting section 42 are stably installed, which is convenient for the user to connect the hinge to the door panel and the door frame respectively, and is convenient for the user to use.

[0042] In this embodiment, at least two groups of connection holes 412 for installing fasteners 8 are provided on the extension section 41, each group of connection holes 412 includes two connection holes 412 arranged at intervals, and the two fasteners 8 installed in each group of connection holes 412 cooperate with the hook groove 421 and the fixing groove 422 respectively.

[0043] When the hinge is used, first install the fixing seat 3 and the connecting seat 2 on the door body and the door frame respectively, and then install the mounting seat 1 in the storage cavity 321, and connect the extension section 41 and the mounting section 42 to the mounting seat 1 and the connecting seat 2 respectively, and then install the fastener 8 corresponding to the hook groove 421 on the extension section 41, and then the user can hang the hook groove 421 on the corresponding fastener 8, so as to achieve preliminary installation of the door panel and the door frame, and then install the fastener 8 corresponding to the fixing groove 422 in the connecting hole 412, and use the fastener 8 to relatively fix the extension section 41 and the mounting section 42.

[0044] Preferably, one end of the fixing groove 422 is tilted upward and extends to one side of the installation section 42, and the hook groove 421 and the fixing groove 422 are arranged in a V shape. When the hinge is reversed, the user can first hook the fastener 8 through the fixing groove 422, and then match the fastener 8 with the hook groove 421. The V-shaped hook groove 421 and the fixing groove 422 facilitate the normal and reverse installation of the hinge, which is convenient for the user to use flexibly.

[0045] The connecting seat 2 is provided with an adjustment slot 223, and an opening 2211 is provided on one side of the adjustment slot 223, and one end of the articulated arm 4 passes through the opening 2211 and is connected to the mounting seat 1; the adjustment slot 223 is rotatably provided with a plurality of adjustment rods 24, and a driving thread 244 is provided on the adjustment rod 24, and an adjustment plate 5 is provided in the adjustment slot 223, and the articulated arm 4 is mounted on the adjustment plate 5, and the adjustment plate 5 is provided with threaded holes 51 adapted to each driving thread 244; the adjustment rod 24 is controlled to rotate, and the driving thread 244 drives the adjustment plate 5 to move relative to each other in the adjustment slot 223, and adjusts the relative position of the articulated arm 4 and the connecting seat 2. In this structure, the relative position of the adjustment plate 5 on the connecting seat 2 is adjusted by the driving thread 244 on the adjustment rod 24, so that the user can adjust the relative position of the articulated arm 4 and the connecting seat 2 according to the needs.

[0046] The adjusting plate 5 described in the utility model is detachably provided with a pressing plate 6 via a fastener 8, and a mounting portion 423 is provided on the articulated arm 4. The pressing plate 6 presses the mounting portion 423 against the adjusting plate 5, and the mounting portion 423 and the adjusting plate 5 are relatively fixed, and anti-slip grooves 425 are provided on the end surfaces where the mounting portion 423 contacts the adjusting plate 5 and the pressing plate 6. The setting of the pressing plate 6 and the anti-slip groove 425 facilitates the installation and disassembly of the articulated arm 4 and the adjusting plate 5, and facilitates the assembly of the hinge.

[0047] The mounting portion 423 is provided with a mounting groove 424, and the fastener 8 passes through the pressure plate 6 and the mounting groove 424 and is connected to the adjustment plate 5. The relative position of the fastener 8 in the mounting groove 424 is adjusted to adjust the relative position of the articulated arm 4 and the adjustment plate 5. The setting of the mounting groove 424 can further increase the flexibility of the installation of the articulated arm 4 on the connecting seat 2, and facilitate the flexible adjustment of the relative position of the connecting seat 2 and the mounting seat 1.

[0048] In this embodiment, the connecting seat 2 includes a shell 22, and the shell 22 includes a first shell 221 and a second shell 222 that are detachably connected. The adjustment groove 223 is formed between the first shell 221 and the second shell 222. The first shell 221 is provided with an opening 2211 for the installation section 42 to pass through, and the first shell 221 is provided with a rotating hole 224, and the second shell 222 is provided with a hinge protrusion 225. The rotating hole 224 is coaxially arranged with the hinge protrusion 225, and the adjusting rod 24 is respectively provided with a rotating protrusion 241 and a hinge hole 243 that are adapted to the rotating hole 224 and the hinge protrusion 225. Preferably, a driving hole 242 is provided at the end of the adjusting rod 24, and the user can control the relative rotation of the adjusting rod 24 and the connecting seat 2 through the driving hole 242.

[0049] Preferably, the housing 22 is provided with a detachable panel 21, which is arranged at the end of the opening 2211 and reduces the entry of debris into the adjustment groove 223. The panel 21 is provided with a movable groove 227 for the installation section 42 to pass through, and the panel 21 is provided with a second control port 228 corresponding to the first control port 226 corresponding to the driving groove, and the second control port 228 corresponds to the fastener 8 on the pressure plate 6.

[0050] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A hinge structure for a door frame, comprising a connecting seat (2) and a mounting seat (1) that are rotatably connected, characterized in that: The mounting seat (1) is detachably provided with a fixing seat (3) connected to the door body or door frame, the fixing seat (3) is provided with a storage cavity (321), the mounting seat (1) is inserted into the storage cavity (321), the connecting seat (2) is provided with a hinged arm (4), the hinged arm (4) extends into the storage cavity (321), and is rotatably connected to the mounting seat (1) through a hinged rod (14), and a supporting bottom plate (322) is provided at the bottom of the storage cavity (321); the end of the storage cavity (321) extends laterally to form a fixing plate (314), the fixing plate (314) is provided with a fixing hole (323), the mounting seat (1) is provided with a mounting plate (11), and a fastener (8) passes through the mounting plate (11) and is connected to the fixing hole (323), so that the fixing seat (3) and the mounting seat (1) are relatively fixed.

2. A hinge structure for a door frame according to claim 1, characterized in that: A positioning protrusion (15) is provided on one side of the mounting plate (11) close to the fixing plate (314), and a positioning groove (16) adapted to the door body or door frame is formed between the outer periphery of the positioning protrusion (15) and the fixing plate (314); the control fastener (8) fixes the fixing seat (3) and the mounting seat (1) relative to each other, and makes the two side walls of the positioning groove (16) respectively press against the door body or door frame.

3. A hinge structure for a door frame according to claim 1, characterized in that: The fixing plate (314) extends toward the end of the hinge rod (14) to form a support plate (311), the support plate (311) extends along the axial direction of the hinge rod (14), and a support portion (312) for supporting the mounting seat (1) is provided on the support plate (311).

4. The hinge structure of a door frame according to claim 1, characterized in that: The articulated arm (4) comprises an extension section (41) extending into the storage cavity (321) and a mounting section (42) detachably arranged on the connecting seat (2); the extension section (41) and the mounting section (42) are detachably connected via a fastener (8); a hook groove (421) and a fixing groove (422) are arranged on the mounting section (42); one end of the hook groove (421) is inclined downward and extends to one side of the mounting section (42).

5. A hinge structure for a door frame according to claim 4, characterized in that: One end of the fixing groove (422) is inclined upward and extends to one side of the installation section (42), and the hook groove (421) and the fixing groove (422) are arranged in a V shape.

6. The hinge structure of a door frame according to claim 1, characterized in that: The connection seat (2) is provided with an adjustment slot (223), one side of which is provided with an opening (2211), one end of the articulated arm (4) passes through the opening (2211) and is connected to the mounting seat (1); a plurality of adjustment rods (24) are rotatably provided in the adjustment slot (223), a driving thread (244) is provided on the adjustment rod (24), an adjustment plate (5) is provided in the adjustment slot (223), the articulated arm (4) is mounted on the adjustment plate (5), and a threaded hole (51) adapted to each driving thread (244) is provided on the adjustment plate (5); the adjustment rod (24) is controlled to rotate, the driving thread (244) drives the adjustment plate (5) to move relatively in the adjustment slot (223), and adjusts the relative position of the articulated arm (4) and the connection seat (2).

7. A hinge structure for a door frame according to claim 6, characterized in that: The adjusting plate (5) is detachably provided with a pressing plate (6) via a fastener (8); a mounting portion (423) is provided on the hinged arm (4); the pressing plate (6) presses the mounting portion (423) against the adjusting plate (5) and fixes the mounting portion (423) and the adjusting plate (5) relatively; and anti-slip grooves (425) are provided on the end surfaces of the mounting portion (423) that are in contact with the adjusting plate (5) and the pressing plate (6).

8. The hinge structure of a door frame according to claim 7, characterized in that: The mounting portion (423) is provided with a mounting groove (424), the fastener (8) passes through the pressure plate (6) and the mounting groove (424) and is connected to the adjustment plate (5), and the relative position of the fastener (8) in the mounting groove (424) is adjusted to thereby adjust the relative position of the articulated arm (4) and the adjustment plate (5).

9. The hinge structure of a door frame according to claim 1, characterized in that: The hinged arm (4) comprises a hinged portion (411) sleeved on a hinged rod (14), support bearings (7) are provided at both ends of the hinged portion (411), and the support bearings (7) are sleeved on the hinged rod (14).

Images