CN219769211U

CN219769211U - Pressure maintaining equipment

Info

Publication number: CN219769211U
Application number: CN202321318987.2U
Authority: CN
Inventors: 宾勇张; 段根文
Original assignee: Dongguan Binshi Electronic Technology Co ltd
Current assignee: Dongguan Binshi Electronic Technology Co ltd
Priority date: 2023-05-26
Filing date: 2023-05-26
Publication date: 2023-09-29
Anticipated expiration: 2033-05-26

Abstract

The utility model relates to the technical field of earphone production, in particular to pressure maintaining equipment which comprises a base, a plurality of first mounting platforms and a plurality of pressure maintaining devices respectively arranged on the first mounting platforms, wherein the first mounting platforms are distributed on the base in a step shape; the pressure maintaining device comprises a second pressing die and a pressure maintaining driving structure which are respectively arranged on the first mounting platform, a lifting plate arranged at the output end of the pressure maintaining driving structure, a first sliding column with one end in sliding connection with the lifting plate, a pressure maintaining plate assembly connected with the other end of the first sliding column, a first pressing die connected with the pressure maintaining plate assembly and an elastic structure arranged between the lifting plate and the pressure maintaining plate assembly. The utility model has compact and light structure, and the plurality of first mounting platforms are arranged in a stacked manner, so that the space utilization rate of the utility model is improved. The elastic piece can buffer or reduce acting force generated by contact or expansion between the first pressing die and the shell of the earphone, and the quality of finished products of the earphone is improved.

Description

Pressure maintaining equipment

Technical Field

The utility model relates to the technical field of earphone production, in particular to pressure maintaining equipment.

Background

Along with the development of technology, people have higher requirements on headphones, and the headphones are required to be small in size and have high-fidelity sound quality capable of realistically reproducing various sound effects. In the current earphone production process, a pressure maintaining process is needed, so that all parts of the earphone can be well assembled together. The utility model discloses including frame and the pressurize mechanism of locating the frame top in patent application number CN202022327317.X, patent application name are a headphone pressurize device, pressurize mechanism is two at least, and two pressurize mechanisms are along controlling the direction interval setting, pressurize mechanism includes pressure post, smelting tool and drive assembly, install the smelting tool mounting panel that is used for installing the smelting tool in the frame, the smelting tool passes through the spiro union mode and installs on the smelting tool mounting panel, be provided with the standing groove with the headphone adaptation on the smelting tool, the pressure post is located directly over the standing groove, drive assembly orders about the pressure post to move in order to pressurize the headphone in the standing groove. If the number of the pressure maintaining mechanisms is too large, the patent application occupies too much space and the space utilization rate is poor; the press stud and the earphone may collide hard, resulting in damage to the press stud or the earphone. Thus, the drawbacks are quite apparent and there is a need to provide a solution.

Disclosure of Invention

In order to solve the technical problems, the utility model aims to provide pressure maintaining equipment.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

the pressure maintaining equipment comprises a base, a plurality of first mounting platforms respectively arranged on the base and a plurality of pressure maintaining devices respectively arranged on the first mounting platforms, wherein the first mounting platforms are distributed on the base in a step shape; the pressure maintaining device comprises a second pressing die and a pressure maintaining driving structure which are respectively arranged on the first mounting platform, a lifting plate arranged at the output end of the pressure maintaining driving structure, a first sliding column with one end in sliding connection with the lifting plate, a pressure maintaining plate assembly connected with the other end of the first sliding column, a first pressing die connected with the pressure maintaining plate assembly and an elastic structure arranged between the lifting plate and the pressure maintaining plate assembly, wherein the first pressing die is arranged above the second pressing die; the pressure maintaining driving structure can drive the lifting plate, the first sliding column, the elastic structure, the pressure maintaining plate assembly and the first pressing die to move in a direction close to or far away from the second pressing die.

Further, the first mounting platform comprises a first mounting plate and a second mounting plate, the pressure maintaining driving structure is arranged on the second mounting plate, the second pressing die is arranged on the first mounting plate, and two ends of the second mounting plate and two ends of the first mounting plate are respectively connected with the base. The second mounting plate is located above the first mounting plate.

Further, the pressure maintaining device further comprises a handle arranged on the base.

Further, the pressure maintaining plate assembly comprises a first pressure maintaining plate, a second pressure maintaining plate and a connecting block, wherein the first pressure maintaining plate and the second pressure maintaining plate are sequentially arranged from top to bottom, the connecting block is respectively inserted into the first pressure maintaining plate and the second pressure maintaining plate, and the elastic structure is positioned between the first pressure maintaining plate and the lifting plate and is respectively in contact with the first pressure maintaining plate and the lifting plate; the first pressure protection plate is fixedly connected with the first sliding column, and the second pressure protection plate is connected with the first pressing die.

Further, the pressure maintaining jig further comprises a first magnet arranged on one side surface of the first pressing die, which is close to the second pressure maintaining plate, a first groove formed by inwards concavely arranging the side wall of the second pressure maintaining plate, which is close to one side surface of the first pressing die, and a second magnet arranged on the inner wall of the first groove; the first magnet can protrude into the first groove, and the magnetism of the first magnet and the magnetism of the second magnet are attracted.

Further, the pressure maintaining jig further comprises a second sliding column with one end inserted into the first mounting plate, and the other end of the second sliding column penetrates through the lifting plate and is in sliding connection with the lifting plate.

Further, a first groove body is arranged on the lifting plate; the second pressure protection plate is provided with a second groove body, and two ends of the elastic structure respectively protrude into the first groove body and the second groove body and can respectively collide with the inner walls of the first groove body and the second groove body.

Further, the pressure maintaining driving structure comprises a rotating rod, a transmission rod, a pressing rod, an installation seat arranged on the second installation plate and a hinge part arranged at the top end of the installation seat, wherein the rotating rod is triangular, and a bottom angle of the rotating rod is hinged with the hinge part; the vertex angle of the rotating rod is hinged with one end of the transmission rod; the other end of the transmission rod is hinged with one end of the compression rod; the other end of the pressing rod penetrates through the mounting seat and is fixedly connected with the lifting plate, and the pressing rod is in sliding connection with the mounting seat.

Further, an anti-slip silica gel sleeve is sleeved on the other bottom corner of the rotating rod.

The utility model has the beneficial effects that: the utility model has compact and light structure, and the plurality of first mounting platforms are arranged in a stacked manner, so that the space utilization rate of the utility model is improved. After the first pressing die is contacted with the shell of the earphone, the first pressing die and the pressure maintaining plate assembly can move upwards through the extrusion elastic structure, so that acting force generated by contact or expansion between the first pressing die and the shell of the earphone is buffered or reduced, further, the problem that the shell of the earphone is damaged due to hard collision between the first pressing die and the shell of the earphone is avoided, the quality of finished products of the earphone is improved, and the service life of the first pressing die is prolonged.

Drawings

Fig. 1 is a schematic perspective view of the present utility model.

Fig. 2 is a schematic view of a partial three-dimensional structure under a pressure maintaining state according to the present utility model.

Fig. 3 is a partial cross-sectional view of the present utility model.

Fig. 4 is a schematic view of a partial three-dimensional structure in a non-pressure maintaining state according to the present utility model.

Reference numerals illustrate:

1. a first stamper; 2. a second stamper; 3. a pressure maintaining driving structure; 4. a base; 5. a first mounting platform; 6. a lifting plate; 7. a first sliding column; 8. a pressure maintaining plate assembly; 9. an elastic structure; 10. a first pressure-maintaining plate; 11. a second pressure-retaining plate; 12. a connecting block; 13. a first magnet; 14. a first groove; 15. a second magnet; 16. a third magnet; 17. a second groove; 18. a fourth magnet; 19. a second sliding column; 20. a first tank body; 21. a second tank body; 22. a collision part; 23. a rotating lever; 24. a transmission rod; 25. a pressing rod; 26. a mounting base; 27. a hinge part; 28. a first mounting plate; 29. a second mounting plate; 30. a handle.

Detailed Description

The utility model will be further described with reference to examples and drawings, to which reference is made, but which are not intended to limit the scope of the utility model.

As shown in fig. 1 to 4, the pressure maintaining device provided by the utility model comprises a base 4, a plurality of first mounting platforms 5 sequentially arranged on the base 4 from top to bottom, and a plurality of pressure maintaining devices respectively arranged on the first mounting platforms 5, wherein the plurality of first mounting platforms 5 are distributed on the base 4 in a step shape; the pressure maintaining device comprises a second pressing die 2 and a pressure maintaining driving structure 3 which are respectively arranged on a first mounting platform 5, a lifting plate 6 arranged at the output end of the pressure maintaining driving structure 3, a first sliding column 7 with one end in sliding connection with the lifting plate 6, a pressure maintaining plate component 8 fixedly connected with the other end of the first sliding column 7, a first pressing die 1 connected with the pressure maintaining plate component 8 and an elastic structure 9 positioned between the lifting plate 6 and the pressure maintaining plate component 8, wherein the first pressing die 1 is positioned above the second pressing die 2; the pressure maintaining driving structure 3 can drive the lifting plate 6, the first sliding column 7, the elastic structure 9, the pressure maintaining plate assembly 8 and the first pressing die 1 to move towards or away from the second pressing die 2.

In particular, the elastic structure 9 may employ a spring. In the practical use process, after the earphone is glued and assembled, the earphone is placed on the second pressing die 2 by a manual or mechanical arm, the lifting plate 6, the first sliding column 7, the elastic structure 9, the pressure maintaining plate assembly 8 and the first pressing die 1 are driven to move downwards in the direction close to the second pressing die 2 by the pressure maintaining driving structure 3, when the first pressing die 1 is abutted against the shell of the earphone, the pressure maintaining driving structure 3 continues to drive the lifting plate 6 to move downwards, and because the first pressing die 1 is abutted against the shell of the earphone, the first pressing die 1 and the pressure maintaining plate assembly 8 do not move downwards any more, the lifting plate 6 can slide downwards relative to the first sliding column 7, so that the gap between the lifting plate 6 and the pressure maintaining plate assembly 8 is reduced, the elastic structure 9 is compressed and stores elastic potential energy, under the action of the elastic force of the elastic structure 9, the pressure maintaining plate assembly 8 and the first pressing die 1 are pressed out of the shell of the earphone, and after the pressure of the first pressing die 1 on the shell of the earphone reaches a preset range, the pressure maintaining driving structure 3 stops to continue to press downwards. After the pressure-maintaining driving structure 3 and the elastic structure 9 drive the first pressing die 1 to be pressed on the shell of the earphone and kept for a period of time, the pressure-maintaining driving structure 3 drives the first pressing die 1 to move upwards, the elastic structure 9 releases elastic potential energy and drives the first sliding column 7 to slide downwards relative to the lifting plate 6 and reset, and the earphone is taken down from the second pressing die 2 manually or mechanically, so that pressure maintaining of the earphone is completed. The plurality of first mounting platforms 5 are arranged in a staggered manner along the horizontal plane, and when the pressure maintaining device on one first mounting platform 5 is installed, the first mounting platform 5 above the first mounting platform 5 cannot block or interfere with the operation of the pressure maintaining device. The plurality of first mounting platforms 5 are arranged in a stacked manner, so that the space utilization rate in the vertical direction is improved, and the space occupation area in the horizontal direction is reduced while the pressure maintaining devices can be arranged as many as possible. The utility model can adjust the elastic force of the elastic structure 9 acting on the pressure maintaining plate assembly 8 and the first pressing die 1 by changing the deformation amount, the rigidity coefficient or the elastic coefficient of the elastic structure 9, and the pressure of the pressure maintaining of the earphone is convenient to adjust. In addition, after the first pressing die 1 contacts with the shell of the earphone, the first pressing die 1 and the pressure maintaining plate assembly 8 can move upwards through the extrusion elastic structure 9, so that acting force generated by contact or expansion between the first pressing die 1 and the shell of the earphone is buffered or reduced, the problem that the first pressing die 1 collides with the shell of the earphone rigidly, and the shell of the earphone is damaged is avoided, the quality of finished products of the earphone is improved, and the service life of the first pressing die 1 is prolonged. The utility model has compact and light structure and convenient pressure maintaining of the earphone.

Further, the first mounting platform 5 includes a first mounting plate 28 and a second mounting plate 29, the pressure maintaining driving structure 3 is disposed on the second mounting plate 29, the second pressing die 2 is disposed on the first mounting plate 28, and two ends of the second mounting plate 29 and the first mounting plate 28 are respectively located at left and right sides of the base 4 and are respectively connected with the base 4. The second mounting plate 29 is located above the first mounting plate 28.

Specifically, the first mounting plate 28 is disposed parallel to the horizontal plane, and the second mounting plate 29 is perpendicular to the first mounting plate 28. The second mounting plate 29 and the first mounting plate 28 are additionally arranged, so that the pressure maintaining driving structure 3 and the second pressing die 2 are conveniently mounted respectively, and the second pressing die 2 and the first pressing die 1 are conveniently mounted on the first mounting platform 5 at intervals up and down. Preferably, a plurality of first mounting platforms 5 may be respectively disposed on the front and rear sides of the base 4, so as to further improve the space utilization of the present utility model.

Further, the pressure maintaining device further comprises a handle 30 arranged on the base 4. The handle 30 is additionally arranged, and workers can drive the pressure maintaining equipment to move through the portable handle 30, so that the position of the pressure maintaining equipment can be conveniently adjusted.

Further, the pressure maintaining plate assembly 8 comprises a first pressure maintaining plate 10, a second pressure maintaining plate 11 and a connecting block 12, wherein the first pressure maintaining plate 10 and the second pressure maintaining plate 11 are sequentially arranged from top to bottom, the connecting block 12 is respectively inserted into the first pressure maintaining plate 10 and the second pressure maintaining plate 11, and the elastic structure 9 is positioned between the first pressure maintaining plate 10 and the lifting plate 6 and respectively abuts against the first pressure maintaining plate 10 and the lifting plate 6; the first pressure-retaining plate 10 is fixedly connected with the first sliding column 7, and the second pressure-retaining plate 11 is connected with the first pressing die 1.

Specifically, the connection block 12 is in interference fit with the first pressure-retaining plate 10 and the second pressure-retaining plate 11 respectively; in the actual use process, the connecting blocks 12 are respectively inserted into the first pressure-retaining plate 10 and the second pressure-retaining plate 11, and the connecting blocks 12 are respectively in interference fit with the first pressure-retaining plate 10 and the second pressure-retaining plate 11, so that the first pressure-retaining plate 10 and the second pressure-retaining plate 11 are firmly connected, the elastic structure 9 is placed between the first pressure-retaining plate 10 and the lifting plate 6, one end of the first sliding column 7 is in sliding connection with the lifting plate 6, the other end of the first sliding column 7 is inserted into the first pressure-retaining plate 10 and is fixedly connected with the first pressure-retaining plate 10, and the second pressure-retaining plate 11 is connected with the first pressing die 1. The pressure-retaining plate assembly 8 is simple in structure and convenient to connect with the lifting plate 6 and the first sliding column 7.

Further, the pressure maintaining jig further comprises a first magnet 13 arranged on one side surface of the first pressing die 1 close to the second pressure maintaining plate 11, a first groove 14 formed by inward concave arrangement of the side wall of the second pressure maintaining plate 11 close to one side surface of the first pressing die 1, and a second magnet 15 arranged on the inner wall of the first groove 14; the first magnet 13 can protrude into the first groove 14, and the first magnet 13 attracts the magnetism of the second magnet 15.

Specifically, the pressure maintaining jig further includes a third magnet 16 disposed on a side surface of the second pressing mold 2, which is close to the first mounting plate 28, a second groove 17 formed by recessing an outer side wall of the first mounting plate 28 inward, and a fourth magnet 18 disposed on an inner wall of the second groove 17, wherein the third magnet 16 can protrude into the second groove 17, and magnetism of the third magnet 16 and magnetism of the fourth magnet 18 attract each other. In the actual use process, through quick magnetic attraction of the first magnet 13 and the second magnet 15 and concave-convex adaptation of the first magnet 13 and the first groove 14, the first magnet 13 and the second magnet 15 can not only realize quick and stable connection of the first pressing die 1 and the second pressing die 11, but also limit the connection or installation position of the first pressing die 1 and the second pressing die 11, so that the problem that dislocation or deviation of the first pressing die 1 and the second pressing die 11 after installation can not be correspondingly pressed is avoided, and the problem that the first pressing die 1 and the second pressing die 2 cannot be correspondingly pressed is solved. The first pressing die 1 and the second pressing die 11 are convenient to assemble and disassemble, when headphones of different models are required to be pressed, the first pressing die 1 can be held by hand to forcefully pull the first magnet 13 out of the first groove 14, the magnetic attraction between the first magnet 13 and the second magnet 15 is overcome, after the proper first pressing die 1 is selected, the first magnet 13 on the first pressing die 1 is inserted into the first groove 14, the quick replacement of the first pressing die 1 can be completed without tools, and the replacement of the first pressing die 1 is convenient. The effect of the third magnet 16 and the fourth magnet 18 with respect to the second die 2 and the first mounting plate 28 is the same as or similar to the effect of the first magnet 13 and the second magnet 15 with respect to the first die 1 and the second pressure retaining plate 11, and will not be described in detail herein.

Further, the pressure maintaining jig further comprises a second sliding column 19 with one end inserted into the first mounting plate 28, and the other end of the second sliding column 19 penetrates through the lifting plate 6 and is in sliding connection with the lifting plate 6.

Specifically, the second sliding column 19 is disposed perpendicularly to the horizontal plane. In the in-service use, drive lifter plate 6 through pressurize drive structure 3 and slide about for second slip post 19, carry out spacing and direction to lifter plate 6 through second slip post 19 for lifter plate 6 only can follow vertical direction and go up and down, thereby improved the accuracy of the stroke that first moulding-die 1 pushed down to the earphone.

Further, the lifting plate 6 is provided with a first groove body 20; the second pressure-maintaining plate 11 is provided with a second groove body 21, and two ends of the elastic structure 9 respectively protrude into the first groove body 20 and the second groove body 21 and can respectively collide with the inner walls of the first groove body 20 and the second groove body 21.

In the actual use process, the two ends of the elastic structure 9 are arranged in the first groove body 20 and the second groove body 21, and the positions of the elastic structure 9 relative to the lifting plate 6 and the second pressure-retaining plate 11 are not easy to change or displace in the deformation process, so that the stability of the utility model is improved.

Further, the pressure maintaining jig further comprises a collision portion 22 disposed at one end of the first sliding column 7 away from the pressure maintaining plate assembly 8, and a bottom end surface of the collision portion 22 can collide with a top end surface of the lifting plate 6.

The interference part 22 is additionally arranged, so that the first sliding column 7 can be prevented from falling out of the lifting plate 6 in the downward movement process, and the first sliding column 7 is convenient to cooperate with the lifting plate 6 and limit.

Further, the pressure maintaining driving structure 3 includes a rotating rod 23, a transmission rod 24, a pressing rod 25, a mounting seat 26 disposed on the second mounting plate 29, and a hinge portion 27 disposed at the top end of the mounting seat 26, wherein the rotating rod 23 is triangular, and a bottom angle of the rotating rod 23 is hinged with the hinge portion 27; the vertex angle of the rotating rod 23 is hinged with one end of a transmission rod 24; the other end of the transmission rod 24 is hinged with one end of the pressing rod 25; the other end of the pressing rod 25 penetrates through the mounting seat 26 and is fixedly connected with the lifting plate 6, and the pressing rod 25 is in sliding connection with the mounting seat 26.

Specifically, the transmission rod 24 is C-shaped; an anti-slip silica gel sleeve is sleeved on the other bottom corner of the rotating rod 23. In the actual pressure maintaining process, after the earphone is placed on the second pressing mold 2, the anti-slip silica gel sleeve is manually or mechanically pushed to drive the rotating rod 23 to rotate relative to the hinge part 27, the rotating rod 23 drives the transmission rod 24 and the pressing rod 25 to move downwards, the pressing rod 25 slides downwards relative to the mounting seat 26, the transmission rod 24 can rotate relative to the pressing rod 25 and the rotating rod 23 respectively until the hinge part of the pressing rod 25 and the transmission rod 24, the hinge part of the transmission rod 24 and the rotating rod 23 and the hinge part of the rotating rod 23 and the hinge part 27 are positioned on the same vertical line, rotation is stopped, at this time, the upward elastic force of the compressed elastic structure 9 cannot drive the pressing rod 25, the transmission rod 24 or/and the rotating rod 23 to rotate, at this time, the pressure maintaining driving structure 3 is in a locking pressure maintaining state, and after the pressure maintaining of the earphone is finished, the anti-slip silica gel sleeve is manually or mechanically pushed upwards, so that the rotating rod 23, the transmission rod 24, the pressing rod 25 and the lifting plate 6 are driven to reset. The pressure maintaining driving structure 3 has the advantages of simple structure, low manufacturing cost, convenient installation, convenient pressure maintaining step and additionally comprises an anti-slip silica gel sleeve, so that the slipping problem during the breaking of the rotating rod 23 is prevented.

All technical features in the embodiment can be freely combined according to actual needs.

The foregoing embodiments are preferred embodiments of the present utility model, and in addition, the present utility model may be implemented in other ways, and any obvious substitution is within the scope of the present utility model without departing from the concept of the present utility model.

Claims

1. A pressure maintaining device, characterized in that: the device comprises a base (4), a plurality of first mounting platforms (5) respectively arranged on the base (4) and a plurality of pressure maintaining devices respectively arranged on the first mounting platforms (5), wherein the plurality of first mounting platforms (5) are distributed on the base (4) in a step shape; the pressure maintaining device comprises a second pressing die (2) and a pressure maintaining driving structure (3) which are respectively arranged on a first mounting platform (5), a lifting plate (6) arranged at the output end of the pressure maintaining driving structure (3), a first sliding column (7) with one end in sliding connection with the lifting plate (6), a pressure maintaining plate assembly (8) connected with the other end of the first sliding column (7), a first pressing die (1) connected with the pressure maintaining plate assembly (8) and an elastic structure (9) positioned between the lifting plate (6) and the pressure maintaining plate assembly (8), wherein the first pressing die (1) is positioned above the second pressing die (2); the pressure maintaining driving structure (3) can drive the lifting plate (6), the first sliding column (7), the elastic structure (9), the pressure maintaining plate assembly (8) and the first pressing die (1) to move towards a direction close to or far away from the second pressing die (2).

2. A pressure maintaining apparatus according to claim 1, wherein: the first mounting platform (5) comprises a first mounting plate (28) and a second mounting plate (29), the pressure maintaining driving structure (3) is arranged on the second mounting plate (29), the second pressing die (2) is arranged on the first mounting plate (28), and two ends of the second mounting plate (29) and two ends of the first mounting plate (28) are respectively connected with the base (4).

3. A pressure maintaining apparatus according to claim 1, wherein: the pressure maintaining equipment further comprises a handle (30) arranged on the base (4).

4. A pressure maintaining apparatus according to claim 1, wherein: the pressure maintaining plate assembly (8) comprises a first pressure maintaining plate (10) and a second pressure maintaining plate (11) which are sequentially arranged from top to bottom, and connecting blocks (12) respectively inserted into the first pressure maintaining plate (10) and the second pressure maintaining plate (11), wherein the elastic structure (9) is positioned between the first pressure maintaining plate (10) and the lifting plate (6) and respectively abuts against the first pressure maintaining plate (10) and the lifting plate (6); the first pressure-retaining plate (10) is fixedly connected with the first sliding column (7), and the second pressure-retaining plate (11) is connected with the first pressing die (1).

5. A pressure maintaining apparatus according to claim 4, wherein: the pressure maintaining equipment further comprises a first magnet (13) arranged on one side surface of the first pressing die (1) close to the second pressure maintaining plate (11), a first groove (14) formed by inward concave arrangement of the side wall of the second pressure maintaining plate (11) close to one side surface of the first pressing die (1) and a second magnet (15) arranged on the inner wall of the first groove (14); the first magnet (13) can protrude into the first groove (14), and the first magnet (13) and the second magnet (15) are attracted.

6. A pressure maintaining apparatus according to claim 2, wherein: the pressure maintaining equipment further comprises a second sliding column (19) with one end inserted into the first mounting plate (28), and the other end of the second sliding column (19) penetrates through the lifting plate (6) and is in sliding connection with the lifting plate (6).

7. A pressure maintaining apparatus according to claim 4, wherein: the lifting plate (6) is provided with a first groove body (20); the second pressure protection plate (11) is provided with a second groove body (21), and two ends of the elastic structure (9) respectively protrude into the first groove body (20) and the second groove body (21) and can respectively collide with the inner walls of the first groove body (20) and the second groove body (21).

8. A pressure maintaining apparatus according to claim 2, wherein: the pressure maintaining driving structure (3) comprises a rotating rod (23), a transmission rod (24), a pressing rod (25), a mounting seat (26) arranged on a second mounting plate (29) and a hinging part (27) arranged at the top end of the mounting seat (26), wherein the rotating rod (23) is triangular, and a bottom angle of the rotating rod (23) is hinged with the hinging part (27); the top angle of the rotating rod (23) is hinged with one end of the transmission rod (24); the other end of the transmission rod (24) is hinged with one end of the pressing rod (25); the other end of the pressing rod (25) penetrates through the mounting seat (26) and is fixedly connected with the lifting plate (6), and the pressing rod (25) is in sliding connection with the mounting seat (26).

9. A pressure maintaining apparatus according to claim 8, wherein: an anti-slip silica gel sleeve is sleeved on the other bottom corner of the rotating rod (23).