CN220955190U - Buffer door-closing hinge - Google Patents

Abstract

The utility model discloses a buffer door-closing hinge which comprises a first sheet, a second sheet and a shaft core, wherein the shaft core comprises an outer tube, a shaft tube, a movable shaft sleeve, a piston rod and a pin shaft; the piston rod can pass through the outer tube and the shaft tube in a vertically movable way, the pin shaft passes through the piston rod, the shaft tube is provided with a straight groove, the movable shaft sleeve is provided with a spiral groove, the pin shaft passes through the straight groove and the spiral groove, and the outer tube is internally provided with a reset mechanism and a damping mechanism. The buffer door-closing hinge has the advantages of compact structure, small volume, convenient and quick operation for adjusting the door-closing angle and the door-closing speed and wide application range.

Description

Buffer door-closing hinge

Technical Field

The utility model relates to the technical field of door and window hardware accessories, in particular to a buffer door closing hinge.

Background

At present, the hinge is widely applied to hinged connection of building doors and windows, the traditional folding hinge only has the hinging effect, when the door is closed, if larger external force exists, the door leaf and the door frame can collide violently, the door leaf or the door frame can be damaged easily, the service lives of the door leaf and the door frame are influenced, the hinge with the buffering effect and the automatic door closing function for avoiding the defects appears in the market, but the existing automatic door closing buffering hinge is complex in structure, the door closing speed is not adjustable, the hinge shaft is thicker, the whole size is large, the installation and use attractiveness is influenced, and certain limitations exist.

Disclosure of utility model

The utility model aims to solve the technical problem of overcoming the defects existing in the prior art and providing the buffering door-closing hinge which is compact in structure, small in size and convenient in door-closing angle and speed adjustment.

In order to solve the technical problems, the utility model adopts the following technical scheme:

The buffer door closing hinge comprises a first sheet, a second sheet and a shaft core, wherein the shaft core comprises an outer tube, a shaft tube, a movable shaft sleeve, a piston rod and a pin shaft, the shaft tube comprises an upper tube section, a middle tube section and a lower tube section, the upper tube section is sleeved in the outer tube, the lower tube section is sleeved in the movable shaft sleeve, the middle tube section is positioned between the outer tube and the movable shaft sleeve, the movable shaft sleeve can rotate relative to the shaft tube, the first sheet is fixedly connected with the circumference of the shaft tube, and the second sheet is fixedly connected with the circumference of the movable shaft sleeve;

The piston rod can vertically movably penetrate through the outer tube and the shaft tube, the pin shaft penetrates through the piston rod, a straight groove is formed in the lower tube section, a spiral groove is formed in the movable shaft sleeve, the pin shaft penetrates out of the straight groove and the spiral groove, and a reset mechanism for driving the piston rod to reset and a damping mechanism for providing damping for resetting of the piston rod are further arranged in the outer tube.

As a further improvement of the above technical scheme:

An upper sealing element and a lower sealing element are arranged in the outer tube, the piston rod comprises a head part and a rod part, a first oil cavity is formed between the upper sealing element and the head part in a surrounding manner, a second oil cavity is formed between the head part and the lower sealing element in a surrounding manner, the rod part passes through the lower sealing element and is arranged, and a flow passage used for communicating the first oil cavity with the second oil cavity is formed in the head part;

The damping mechanism comprises a valve needle fixedly arranged on the upper sealing piece and a valve body fixedly arranged on the head, a through hole is formed in the valve body, the through hole is communicated with the through channel, and the valve needle penetrates through the through hole to be in clearance fit with the through hole.

The valve needle is provided with a small-diameter section and a large-diameter section, the small-diameter section is positioned on one side of the valve needle, which is close to the upper sealing element, and the large-diameter section is positioned on one side of the valve needle, which is far away from the upper sealing element.

The upper sealing piece is connected with an adjusting screw in a threaded mode, and the valve needle is fixedly connected to the end portion of the adjusting screw.

The reset mechanism comprises a reset spring, the piston rod penetrates through the reset spring, one end of the reset spring is in abutting contact with the head, and the other end of the reset spring is in abutting contact with the lower sealing piece.

A first sealing ring is arranged between the adjusting screw and the upper sealing piece, and a second sealing ring is arranged between the upper sealing piece and the outer tube; a third sealing ring is arranged between the valve body and the head, and a fourth sealing ring is arranged between the head and the outer tube; a fifth sealing ring is arranged between the rod part and the lower sealing piece, and a sixth sealing ring is arranged between the lower sealing piece and the outer tube.

The movable connecting mechanism comprises a first annular groove arranged at the bottom of the middle pipe section, a second annular groove arranged at the top of the movable shaft sleeve, and a plurality of groups of balls which are rotatably arranged between the first annular groove and the second annular groove.

The spiral groove comprises a spiral section and a horizontal section, and the horizontal section is positioned on the lower side of the spiral section.

The end cover of the outer tube is provided with a first end cover, and the end cover of the movable shaft sleeve is provided with a second end cover.

The first page is provided with a first sleeve, the first sleeve is sleeved on the shaft core, and the middle pipe section is provided with a first annular tooth structure which is used for being fixedly connected with the first sleeve in the circumferential direction;

The second page piece is provided with a second sleeve, the second sleeve is sleeved on the shaft core, and the movable shaft sleeve is provided with a second annular tooth-shaped structure which is used for being fixedly connected with the second sleeve in the circumferential direction;

a bearing is arranged between the first sleeve and the second sleeve.

Compared with the prior art, the utility model has the advantages that:

The movable shaft sleeve of the buffering door-closing hinge is rotatably sleeved on the shaft tube, the movable shaft sleeve is driven to rotate on the shaft tube through relative rotation between the first page piece and the second page piece, and the pin shaft drives the piston rod to move downwards and compress the reset mechanism through the cooperation between the pin shaft and the spiral groove and the straight groove when the door is opened, so that the damping mechanism provides damping for the downward movement of the piston rod and avoids overlarge door opening impact; after the door body is opened, the reset mechanism acts on and drives the piston rod to move upwards for reset, the pin shaft drives the movable shaft sleeve to rotate reversely on the shaft tube through the cooperation between the pin shaft and the spiral groove and the straight groove, the damping mechanism provides damping for the upward movement of the piston rod, the door closing impact is avoided, the door has the advantages of compact structure and small size, the door closing angle and the door closing speed can be adjusted through the damping mechanism, the adjustment operation is convenient and fast, the application range is wide, the working reliability is strong, and the use requirements of users are met.

Drawings

Fig. 1 is a schematic structural view of a buffer door hinge.

Fig. 2 is a schematic structural view of the buffer door hinge in an exploded state.

Fig. 3 is a schematic structural view of the shaft core.

Fig. 4 is a schematic view of the internal structure of the shaft core.

Fig. 5 is a schematic structural view of the exploded state of the shaft core.

Fig. 6 is a schematic structural view of the shaft tube.

Fig. 7 is a schematic structural view of the movable sleeve.

Fig. 8 is a schematic view of a semi-sectional structure of the shaft core.

Fig. 9 is an enlarged view of the upper portion of the shaft core in fig. 8.

Fig. 10 is a schematic structural view of the damping mechanism in an exploded state.

Fig. 11 is an enlarged view of the lower portion of the shaft core of fig. 8.

Fig. 12 is a schematic view showing an exploded state of the articulating mechanism.

Legend description:

1. A first sheet; 101. a first sleeve; 2. a second sheet; 201. a second sleeve; 3. a shaft core; 301. an outer tube; 302. a shaft tube; 3021. an upper pipe section; 3022. a middle pipe section; 3023. a lower pipe section; 303. a movable shaft sleeve; 304. a piston rod; 3041. a head; 3042. a stem portion; 305. a pin shaft; 4. a straight groove; 5. a spiral groove; 501. a helical section; 502. a horizontal section; 6. a reset mechanism; 601. a return spring; 7. a damping mechanism; 701. a valve needle; 7011. a small diameter section; 7012. a large diameter section; 702. a valve body; 703. a through-flow hole; 8. an upper seal; 9. a lower seal; 10. a first oil chamber; 11. a second oil chamber; 12. a flow-through channel; 13. an adjusting screw; 14. a bearing; 15. a first seal ring; 16. a second seal ring; 17. a third seal ring; 18. a fourth seal ring; 19. a fifth seal ring; 20. a sixth seal ring; 21. a movable connecting mechanism; 2101. a second annular groove; 2102. a ball; 22. a first end cap; 23. a second end cap; 24. a first annular tooth structure; 25. the second annular tooth structure.

Detailed Description

The utility model is described in further detail below with reference to the drawings and the specific examples.

As shown in fig. 1 to 12, the buffering door closing hinge of the present embodiment includes a first sheet 1, a second sheet 2 and a shaft core 3, the shaft core 3 includes an outer tube 301, a shaft tube 302, a movable shaft sleeve 303, a piston rod 304 and a pin shaft 305, the shaft tube 302 includes an upper tube section 3021, a middle tube section 3022 and a lower tube section 3023, the upper tube section 3021 is sleeved in the outer tube 301, the lower tube section 3023 is sleeved in the movable shaft sleeve 303, the middle tube section 3022 is located between the outer tube 301 and the movable shaft sleeve 303, the movable shaft sleeve 303 can rotate relative to the shaft tube 302, the first sheet 1 is fixedly connected with the shaft tube 302 in the circumferential direction, and the second sheet 2 is fixedly connected with the movable shaft sleeve 303 in the circumferential direction; the piston rod 304 can be movably arranged in the outer tube 301 and the shaft tube 302 in a penetrating way up and down, the pin shaft 305 is arranged on the piston rod 304 in a penetrating way, the lower tube section 3023 is provided with a straight groove 4, the movable shaft sleeve 303 is provided with a spiral groove 5, the pin shaft 305 penetrates out of the straight groove 4 and the spiral groove 5 to be arranged, and the outer tube 301 is internally provided with a reset mechanism 6 for driving the piston rod 304 to reset and a damping mechanism 7 for providing damping for the reset of the piston rod 304. The movable shaft sleeve 303 of the buffering door-closing hinge is rotatably sleeved on the shaft tube 302, the movable shaft sleeve 303 is driven to rotate on the shaft tube 302 through relative rotation between the first leaf 1 and the second leaf 2, the pin shaft 305 is matched with the spiral groove 5 and the straight groove 4 during door opening so as to realize that the rotation of the movable shaft sleeve 303 drives the piston rod 304 to move downwards and compress the reset mechanism 6, and the damping mechanism 7 provides damping for the downward movement of the piston rod 304 and avoids overlarge door opening impact; after the door body is opened, the reset mechanism 6 acts on and drives the piston rod 304 to move upwards for reset, the pin shaft 305 drives the movable shaft sleeve 303 to rotate reversely on the shaft tube 302 through the cooperation between the pin shaft 305 and the spiral groove 5 and the straight groove 4, the damping mechanism 7 provides damping for the upward movement of the piston rod 304, the door closing impact is avoided, the door closing device has the advantages of compact structure and small size, and the door closing angle and the door closing speed can be adjusted through the damping mechanism 7, so that the door closing device is convenient and quick to adjust, wide in application range and high in working reliability, and the use requirement of a user is met.

Specifically, in this embodiment, the first sheet 1 is connected to the door frame, the second sheet 2 is connected to the door leaf, the first sheet 1 is fixedly disposed circumferentially with the outer tube 301 and the shaft tube 302, and when the door body is in the closed state, the first sheet 1 is overlapped with the second sheet 2.

Preferably, an upper sealing element 8 and a lower sealing element 9 are arranged in the outer tube 301, the piston rod 304 comprises a head part 3041 and a rod part 3042, a first oil cavity 10 is formed between the upper sealing element 8 and the head part 3041 in a surrounding manner, a second oil cavity 11 is formed between the head part 3041 and the lower sealing element 9 in a surrounding manner, the rod part 3042 passes through the lower sealing element 9, and a flow passage 12 used for communicating the first oil cavity 10 with the second oil cavity 11 is formed in the head part 3041; the damping mechanism 7 comprises a valve needle 701 fixedly arranged on the upper sealing member 8 and a valve body 702 fixedly arranged on the head 3041, wherein a through-flow hole 703 is formed in the valve body 702, the through-flow hole 703 is communicated with the through-flow channel 12, and the valve needle 701 passes through the through-flow hole 703 and is in clearance fit with the through-flow hole 703.

Preferably, the valve needle 701 is provided with a small diameter section 7011 and a large diameter section 7012, the small diameter section 7011 being located on the side of the valve needle 701 near the upper seal 8, and the large diameter section 7012 being located on the side of the valve needle 701 far from the upper seal 8. In this embodiment, the valve needle 701 is provided with a small diameter section 7011 and a large diameter section 7012, and the specific working procedure of the damping mechanism 7 is as follows: when the door body is in an open state, the piston rod 304 is in a state of compressing the return spring 601, and at the moment, the large-diameter section 7012 of the valve needle 701 is positioned in the through-flow hole 703 of the valve body 702; when the door body is closed under the action of the return spring 601, the included angle between the first leaf 1 and the second leaf 2 is continuously reduced, the movable shaft sleeve 303 rotates relative to the shaft tube 302, the pin shaft 305 and the piston rod 304 move upwards for return, namely the head 3041 of the piston rod 304 moves upwards relative to the valve needle 701, at the moment, the gap between the large-diameter section 7012 and the through-flow hole 703 is unchanged, the diameter of hydraulic oil in the first oil cavity 10, which is input into the second oil cavity 11 from the through-flow hole 703 and the through-flow channel 12, is small, the moving speed of the piston rod 304 is slow, the buffer door closing is realized, and the door body is in a mute door closing state at this stage; when the head 3041 continues to move up to the small-diameter section 7011 (assuming that the included angle between the first sheet 1 and the second sheet 2 is 15 degrees at this time), the gap between the small-diameter section 7011 and the through-flow hole 703 becomes larger, the diameter flow of hydraulic oil in the first oil chamber 10, which is input into the second oil chamber 11 from the through-flow hole 703 and the through-flow channel 12, is increased, the moving speed of the piston rod 304 is increased, and the door body is in an accelerated locking and closing state at this stage, so that the buffer door closing is realized until 15 degrees later, and then the locking and closing are accelerated. In summary, the relative position between the junction of the small-diameter section 7011 and the large-diameter section 7012 of the valve needle 701 and the through-flow hole 703 corresponds to the angle of the hinge included angle for converting the door body from the mute door closing state to the accelerated door locking door closing state, so that the door body applying the buffering door closing hinge has the mute door closing and accelerated door locking stage conversion functions.

Preferably, the upper sealing member 8 is screwed with an adjusting screw 13, and the valve needle 701 is fixedly connected to an end of the adjusting screw 13. In this embodiment, the adjusting screw 13 is screwed onto the upper sealing member 8, and the progress of the adjusting screw 13 (i.e. the valve needle 701) in the outer tube 301 can be adjusted by rotating, so as to adjust the relative position between the junction of the small diameter section 7011 and the large diameter section 7012 and the through-flow hole 703, further change the angle of the hinge angle for converting the door body from the mute door closing state to the acceleration door locking state, change the door closing speed, and have simple debugging operation, thereby being beneficial to improving the assembly efficiency.

Preferably, the return mechanism 6 includes a return spring 601, the piston rod 304 is inserted into the return spring 601, one end of the return spring 601 is in contact with the head 3041, and the other end of the return spring 601 is in contact with the lower seal 9. In this embodiment, the reset mechanism 6 adopts the form of the reset spring 601, and has the advantages of convenient and quick assembly, low cost and long service life.

As shown in fig. 9 and 11, preferably, a first sealing ring 15 is arranged between the adjusting screw 13 and the upper sealing member 8, and a second sealing ring 16 is arranged between the upper sealing member 8 and the outer tube 301; a third sealing ring 17 is arranged between the valve body 702 and the head 3041, and a fourth sealing ring 18 is arranged between the head 3041 and the outer tube 301; a fifth seal ring 19 is provided between the stem 3042 and the lower seal 9, and a sixth seal ring 20 is provided between the lower seal 9 and the outer tube 301. In this embodiment, the first sealing ring 15 is mainly used to prevent hydraulic oil from seeping out from the gap between the adjusting screw 13 and the upper sealing member 8, the second sealing ring 16 is mainly used to prevent hydraulic oil from seeping out from the gap between the upper sealing member 8 and the outer tube 301, and the functions of the third sealing ring 17, the fourth sealing ring 18, the fifth sealing ring 19 and the sixth sealing ring 20 are the same, which are not described here again, so that the first oil cavity 10 formed by the upper sealing member 8 and the head 3041 and the second oil cavity 11 formed by the head 3041 and the lower sealing member 9 are kept in a sealed state, which is beneficial to prolonging the service life of the buffering door-closing hinge.

As shown in fig. 12, preferably, a movable connection mechanism 21 is provided between the shaft tube 302 and the movable sleeve 303, and the movable connection mechanism 21 includes a first annular groove (not shown) provided at the bottom of the middle tube section 3022, a second annular groove 2101 provided at the top of the movable sleeve 303, and a plurality of sets of balls 2102 rotatably provided between the first annular groove and the second annular groove 2101. In this embodiment, the shaft tube 302 and the movable shaft sleeve 303 are movably connected through the ball 2102, and when the shaft tube 302 and the movable shaft sleeve 303 rotate relatively, the ball 2102 can roll between the first annular groove and the second annular groove 2101, so that sliding friction is effectively reduced, and the wear-resisting device has the advantages of good wear resistance, low noise and stable operation.

As shown in fig. 7, the spiral groove 5 preferably includes a spiral section 501 and a horizontal section 502, and the horizontal section 502 is located at the lower side of the spiral section 501. In this embodiment, the spiral groove 5 has a spiral section 501 and a horizontal section 502 sequentially arranged from top to bottom, and the specific working process is as follows: when the door body is in a closed state, the first sheet 1 and the second sheet 2 are overlapped, the pin shaft 305 is positioned at the upper part of the spiral section 501, and the piston rod 304 does not compress the return spring 601; in the process that a user opens the door body, the included angle between the first leaf 1 and the second leaf 2 is continuously increased, the movable shaft sleeve 303 rotates relatively on the shaft tube 302, at this time, the pin shaft 305 moves downwards under the action of the inclined plane of the spiral section 501, that is, the pin shaft 305 moves downwards in the straight groove 4, and the piston rod 304 is driven to compress the reset spring 601 downwards; when the pin shaft 305 moves to the horizontal section 502, the door body is continuously opened, the included angle between the first sheet 1 and the second sheet 2 is continuously increased, the pin shaft 305 horizontally moves along the horizontal section 502, that is, the height of the pin shaft 305 in the straight groove 4 is kept unchanged, and the piston rod 304 does not continuously compress the return spring 601; when the user no longer opens the door, the force of the return spring 601 is perpendicular to the plane of the horizontal segment 502, so that the pin 305 no longer moves, the door is kept in the open state, the minimum included angle between the first sheet 1 and the second sheet 2 is called a self-locking angle (assuming 90 degrees), and when the included angle between the first sheet 1 and the second sheet 2 is greater than the self-locking angle, the user is required to actively close the door. In the process of closing the door body by a user, the included angle between the first sheet 1 and the second sheet 2 is continuously reduced, and when the pin shaft 305 moves to the spiral section 501 (i.e. the included angle between the first sheet 1 and the second sheet 2 is smaller than the self-locking angle), under the action of the reset spring 601, the pin shaft 305 moves upwards along the inclined plane of the spiral section 501, i.e. the pin shaft 305 moves upwards in the straight groove 4, until the pin shaft 305 resets to the upper part of the spiral section 501, so that the door body is in a closed state again. In summary, the spiral section 501 corresponds to a door opening angle (less than 90 degrees) that enables the door body to realize a self-closing function, and the horizontal section 502 corresponds to a self-locking angle (greater than or equal to 90 degrees) that enables the door body to be automatically maintained in an open state.

Preferably, the end cap of the outer tube 301 is provided with a first end cap 22 and the end cap of the movable sleeve 303 is provided with a second end cap 23.

As shown in fig. 1 and 2, preferably, the first sheet 1 is provided with a first sleeve 101, the first sleeve 101 is sleeved on the shaft core 3, and the middle pipe section 3022 is provided with a first annular tooth-shaped structure 24 for fixedly connecting with the first sleeve 101 in the circumferential direction; the second leaf 2 is provided with a second sleeve 201, the second sleeve 201 is sleeved on the shaft core 3, and the movable shaft sleeve 303 is provided with a second annular tooth-shaped structure 25 which is used for being fixedly connected with the second sleeve 201 in the circumferential direction; a bearing 14 is provided between the first sleeve 101 and the second sleeve 201. In the embodiment, a group of first sleeves 101 are formed on the first sheet 1, two groups of second sleeves 201 are formed on the second sheet 2, the first sheet 1 is connected to the shaft core 3 through the first sleeves 101, and the second sheet 2 is connected to the shaft core 3 through the second sleeves 201, so that the relative rotation between the second sheet 2 and the first sheet 1 can drive the movable shaft sleeve 303 to rotate on the shaft tube 302, and the rotary shaft sleeve has the advantages of simple structure and convenience and rapidness in installation and disassembly; by arranging the bearing 14 between the first sleeve 101 and the second sleeve 201, the friction coefficient between the second sleeve 201 and the first sleeve 101 during relative rotation can be reduced, the service life of the buffer door-closing hinge can be effectively prolonged, and the bearing 14 is made of nylon.

Specifically, the lower end of the rod portion 3042 is provided as an external thread section, with the purpose of: if the hinge is closed when the door is not installed, the door cannot be installed, the second end cover 23 at the end part of the movable shaft sleeve 303 can be taken down, an opening screw is placed in the shaft tube 302 and is in threaded connection with the external thread section, the piston rod 304 is pulled down under the action of the threads, the hinge is opened by a certain angle, and the installation efficiency is improved.

The above description is merely a preferred embodiment of the present utility model, and the scope of the present utility model is not limited to the above examples. Modifications and variations which would be obvious to those skilled in the art without departing from the spirit of the utility model are also considered to be within the scope of the utility model.

Claims (10)

1. The utility model provides a buffering door hinge, includes first page (1), second page (2) and axle core (3), its characterized in that, axle core (3) include outer tube (301), central siphon (302), movable axle sleeve (303), piston rod (304) and round pin axle (305), central siphon (302) include upper pipe section (3021), well pipeline section (3022) and lower pipeline section (3023), upper pipe section (3021) cover is located in outer tube (301), lower pipeline section (3023) cover is located in movable axle sleeve (303), well pipeline section (3022) are located between outer tube (301) and movable axle sleeve (303), movable axle sleeve (303) can rotate for central siphon (302), first page (1) with central siphon (302) circumference fixed connection, second page (2) with movable axle sleeve (303) circumference fixed connection;

The piston rod (304) can be movably arranged in the outer tube (301) and the shaft tube (302) in a penetrating mode, the pin shaft (305) is arranged on the piston rod (304) in a penetrating mode, the lower tube section (3023) is provided with a straight groove (4), the movable shaft sleeve (303) is provided with a spiral groove (5), the pin shaft (305) penetrates out of the straight groove (4) and the spiral groove (5) in a penetrating mode, and a reset mechanism (6) for driving the piston rod (304) to reset and a damping mechanism (7) for providing damping for resetting of the piston rod (304) are further arranged in the outer tube (301).

2. The buffering door-closing hinge according to claim 1, characterized in that an upper sealing element (8) and a lower sealing element (9) are arranged in the outer tube (301), the piston rod (304) comprises a head (3041) and a rod part (3042), a first oil cavity (10) is formed between the upper sealing element (8) and the head (3041) in a surrounding manner, a second oil cavity (11) is formed between the head (3041) and the lower sealing element (9) in a surrounding manner, the rod part (3042) passes through the lower sealing element (9) to be arranged, and a through-flow channel (12) used for communicating the first oil cavity (10) with the second oil cavity (11) is formed in the head (3041);

The damping mechanism (7) comprises a valve needle (701) fixedly arranged on the upper sealing piece (8) and a valve body (702) fixedly arranged on the head (3041), a through-flow hole (703) is formed in the valve body (702), the through-flow hole (703) is communicated with the through-flow channel (12), and the valve needle (701) penetrates through the through-flow hole (703) to be arranged and in clearance fit with the through-flow hole (703).

3. Buffer door hinge according to claim 2, characterized in that the valve needle (701) is provided with a small diameter section (7011) and a large diameter section (7012), the small diameter section (7011) being located on the side of the valve needle (701) close to the upper seal (8), the large diameter section (7012) being located on the side of the valve needle (701) remote from the upper seal (8).

4. A buffer door hinge according to claim 3, characterized in that the upper sealing member (8) is screwed with an adjusting screw (13), and the valve needle (701) is fixedly connected to the end of the adjusting screw (13).

5. The cushion door-closing hinge according to claim 4, wherein the return mechanism (6) comprises a return spring (601), the piston rod (304) is inserted into the return spring (601), one end of the return spring (601) is in abutting contact with the head (3041), and the other end of the return spring (601) is in abutting contact with the lower sealing member (9).

6. Buffer door hinge according to claim 5, characterized in that a first sealing ring (15) is arranged between the adjusting screw (13) and the upper sealing member (8), and a second sealing ring (16) is arranged between the upper sealing member (8) and the outer tube (301);

A third sealing ring (17) is arranged between the valve body (702) and the head (3041), and a fourth sealing ring (18) is arranged between the head (3041) and the outer tube (301);

A fifth sealing ring (19) is arranged between the rod part (3042) and the lower sealing piece (9), and a sixth sealing ring (20) is arranged between the lower sealing piece (9) and the outer tube (301).

7. The buffering door-closing hinge according to claim 1, characterized in that a movable connecting mechanism (21) is arranged between the shaft tube (302) and the movable shaft sleeve (303), the movable connecting mechanism (21) comprises a first annular groove arranged at the bottom of the middle tube section (3022), a second annular groove (2101) arranged at the top of the movable shaft sleeve (303), and a plurality of groups of balls (2102) rotatably arranged between the first annular groove and the second annular groove (2101).

8. The cushion door hinge according to claim 1, wherein the spiral groove (5) comprises a spiral section (501) and a horizontal section (502), the horizontal section (502) being located at the lower side of the spiral section (501).

9. Buffer door hinge according to claim 1, characterized in that the end cap of the outer tube (301) is provided with a first end cap (22) and the end cap of the movable sleeve (303) is provided with a second end cap (23).

10. The buffering door-closing hinge according to any one of claims 1 to 9, characterized in that a first sleeve (101) is arranged on the first sheet (1), the first sleeve (101) is sleeved on the shaft core (3), and a first annular toothed structure (24) used for being fixedly connected with the first sleeve (101) in the circumferential direction is arranged on the middle pipe section (3022);

A second sleeve (201) is arranged on the second leaf (2), the second sleeve (201) is sleeved on the shaft core (3), and a second annular tooth-shaped structure (25) used for being fixedly connected with the second sleeve (201) in the circumferential direction is arranged on the movable shaft sleeve (303);

A bearing (14) is arranged between the first sleeve (101) and the second sleeve (201).