CN112701403A

CN112701403A - Lithium battery pack

Info

Publication number: CN112701403A
Application number: CN202110310441.1A
Authority: CN
Inventors: 牛龙龙; 侯庆云; 侯文玉
Original assignee: Xinxiang Hongsun Energy Co ltd
Current assignee: Xinxiang Hongsun Energy Co ltd
Priority date: 2021-03-24
Filing date: 2021-03-24
Publication date: 2021-04-23
Anticipated expiration: 2041-03-24
Also published as: CN112701403B

Abstract

The invention relates to the field of new energy, in particular to a lithium battery pack. The technical problem to be solved is as follows: the lithium battery pack has the advantages that the lithium battery pack can absorb shock in an all-dimensional mode and can be fixed better. The utility model provides a lithium battery pack, is including holding case, spacing, apron, first damper and second damper, and the vent has all been opened on the both sides wall upper portion that holds the case, is equipped with the filter screen in the vent, and the inside wall upper portion rigid coupling that holds the case has spacing, and the top of spacing is provided with the apron through the bolt, and spacing downside holds and installs first damper between the case both sides wall, is equipped with second damper in the first damper. According to the invention, the battery pack can be protected and damped in an all-around manner through the matching of the first damping mechanism and the second damping mechanism, and the battery pack can be better fixed through the second damping mechanism, so that the battery pack is prevented from loosening.

Description

Lithium battery pack

Technical Field

The invention relates to the field of new energy, in particular to a lithium battery pack.

Background

The battery pack is divided into a series battery pack and a parallel battery pack, the voltage of each battery is required to be the same by the parallel battery pack, the output voltage is equal to the voltage of one battery, the parallel battery pack can provide stronger current, and the series battery pack does not have excessive requirements.

Through retrieval, for example, patent with patent publication number CN112436221A discloses a lithium battery pack, which includes a casing for mounting a plurality of batteries, a heat dissipation assembly for cooling the batteries is arranged in the casing, a sealing cover for closing the casing is arranged on the casing, air holes are arranged on the sealing cover, and an air permeation assembly for opening the air holes is arranged on the sealing cover; this lithium cell group can not all-round carry out the shock attenuation to the battery, can not be better fix the group battery.

Aiming at the problems, a lithium battery pack which can realize all-dimensional shock absorption and can be fixed better is developed.

Disclosure of Invention

The present invention is directed to a lithium battery pack to solve the above problems.

The technical scheme of the invention is as follows: a lithium battery pack comprises a containing box, a limiting frame, a cover plate, a first damping mechanism and a second damping mechanism, wherein ventilation openings are formed in the upper portions of two side walls of the containing box, a filter screen is arranged in the ventilation openings, the limiting frame is fixedly connected to the upper portion of the inner side wall of the containing box, the cover plate is arranged at the top of the limiting frame through bolts, the first damping mechanism is arranged between the two side walls of the containing box on the lower side of the limiting frame, and the second damping mechanism is arranged in the first damping mechanism; first damper is including first branch, the second branch, pneumatic spring, link and shock attenuation frame, the shock attenuation frame sets up and holds the incasement at spacing downside, the link is all installed to the both sides wall of shock attenuation frame, two pneumatic spring are installed to the lateral wall rotary type of link, first branch is installed through the bearing to the pneumatic spring of upside, first branch difference rigid coupling is holding the both sides wall of incasement, the pneumatic spring of downside installs the second branch through the bearing, second branch difference rigid coupling is holding the both sides wall of incasement.

As a preferred technical scheme of the invention, the second damping mechanism comprises a fixed frame, a positioning frame, a fixed rod, a sliding frame, a first reset spring, a second reset spring, a sliding rod, a limiting block, a mounting frame, a heat dissipation frame and a containing part, wherein the containing part is arranged in the heat dissipation frame, the mounting frame is respectively arranged at two sides of the heat dissipation frame through bolts, the mounting frame is provided with two chutes, the middle parts of two side walls in the damping frame are respectively connected with the fixed frame, the two side walls in the damping frame at two sides of the fixed frame are respectively provided with the positioning frame, the fixed rod is connected between the two corresponding positioning frames and penetrates through the fixed frame, the sliding frame is arranged at two sides of the fixed rod in a sliding way, the fixed rods at the outer sides of the two sliding frames are respectively sleeved with two first reset springs, one end of each first reset spring, the dead lever cover between two carriages has two second reset spring, the one end and the carriage rigid coupling that corresponds of second reset spring, second reset spring's the other end and mount rigid coupling, the lateral wall mid-mounting of carriage has the slide bar, and four slide bars are the slidingtype setting respectively in the chute that corresponds, and the stopper is installed to the lateral wall of slide bar.

According to a preferable technical scheme of the invention, the containing part comprises a battery box, a box cover, a first handle, a connecting block and a second handle, the battery box is arranged in the heat dissipation frame, the box cover is arranged at the top of the battery box through a bolt, the first handle is arranged on two sides of the box cover through bolts, the connecting block is fixedly connected to two side walls in the battery box, and the second handle is arranged at the top of the connecting block through a bolt.

The invention also comprises connecting frames, sliding sleeves, clamping rods, rotating rods, fixed disks, rotating disks and sliding blocks, wherein the sliding frames are fixedly connected between the two connecting frames, the bottom in each connecting frame is provided with the three sliding sleeves, the clamping rods are arranged between the three sliding sleeves in a sliding mode and penetrate through a battery box, the clamping rods and the heat dissipation frames are arranged in a sliding mode, the rotating rods are arranged in the sliding frames in a sliding mode, the rotating rods are provided with the two fixed disks, the two sides of each fixed disk are provided with arc-shaped grooves, the top ends of the rotating rods are provided with the rotating disks, the inner ends of the two clamping rods are provided with the sliding blocks, and the two sliding blocks are respectively arranged between the upper corresponding arc-shaped groove and the lower corresponding.

The invention further comprises fans, support plates, rotating rods, baffles and torsional springs, wherein four fans are arranged on two sides of a limiting frame, an air suction opening is formed in the limiting frame on the lower side of each fan, a plurality of ventilation holes are formed in two side walls in the limiting frame, a plurality of ventilation holes are formed in two side walls of a containing box, the limiting frame is communicated with the ventilation holes on the corresponding side of the containing box relatively, two groups of support plates which are distributed up and down are respectively arranged on two sides of the inner side wall of the limiting frame, which are close to the ventilation holes, two ends of the upper rotating rod and the lower rotating rod are rotatably arranged between the support plates which are opposite to the two sides of the ventilation holes, the middle of each group of rotating rods is fixed with the baffles, the baffles on the upper rotating rod and the lower rotating rod are in contact fit, the torsional springs are sleeved on.

Has the advantages that:

1. the battery pack can be protected and damped in an all-dimensional manner through the matching of the first damping mechanism and the second damping mechanism, and the battery pack can be better fixed through the second damping mechanism, so that the battery pack is prevented from loosening;

2. the clamping rod is inserted into the heat dissipation frame, so that the battery pack can be further fixed;

3. the circulation of air can be completed by the cooperation of the operation of the fan and the ventilation holes, so that the temperature of the battery pack can be reduced by continuously circulating air.

Drawings

Fig. 1 is a schematic perspective view of the present invention.

Fig. 2 is a schematic perspective view of the containing box of the present invention.

Fig. 3 is a schematic perspective view of the first damper mechanism according to the present invention.

Fig. 4 is a schematic perspective view of the shock-absorbing frame of the present invention.

Fig. 5 is a schematic perspective view of the pneumatic spring of the present invention.

Fig. 6 is a schematic perspective view of a second damper mechanism according to the present invention.

Fig. 7 is a schematic perspective view of the mounting bracket of the present invention.

Fig. 8 is a schematic perspective view of the fixing frame of the present invention.

Fig. 9 is a schematic perspective view of a heat dissipation frame according to the present invention.

Fig. 10 is a schematic perspective view of the battery box of the present invention.

Fig. 11 is a schematic perspective view of the sliding frame according to the present invention.

Fig. 12 is a schematic perspective view of the fixing plate of the present invention.

Fig. 13 is a perspective view of the rotary disk of the present invention.

FIG. 14 is a schematic perspective view of the slider of the present invention.

Fig. 15 is a schematic perspective view of the spacing frame of the present invention.

Fig. 16 is a schematic perspective view of the baffle of the present invention.

Labeled as: a storage box, a 2.. ventilation opening, a 3.. limiting frame, a 4.. cover plate, a 5.. first damping mechanism, a 501.. first supporting rod, a 502.. second supporting rod, a 503.. pneumatic spring, a 504.. connecting frame, a 505.. damping frame, a 6.. second damping mechanism, a 601.. fixing frame, a 602.. positioning frame, a 603.. fixing rod, a 604.. sliding frame, a 605.. first return spring, a 6051.. second return spring, a 6052.. sliding rod, a 606.. limiting block, a 607.. mounting frame, a 608.. chute, a 609.. heat dissipation frame, a 610.. battery box, a 611.. box cover, a 612.. first handle, a connecting block, a 613.. second chute, a 609.. handle, a heat dissipation frame, a 610.. battery box, a 611.. box cover, a 612.. first handle, a connecting block, a 613.. second chute, a 7.. 9.. sliding frame, a 9.. connecting rod, 11.. a rotation lever, 12.. a fixed disk, 13.. an arc-shaped groove, 14.. a rotation disk, 15.. a slide block, 16.. a fan, 17.. a ventilation hole, 18.. an extension plate, 19.. a rotation lever, 20.. a baffle plate, 21.. a torsion spring.

Detailed Description

The invention is described in further detail below with reference to the drawings and the detailed description, but the invention is not limited to the scope of protection and application.

Example 1

The utility model provides a lithium battery pack, as shown in figure 1, figure 2 and figure 3, including holding case 1, spacing frame 3, apron 4, first damper 5 and second damper 6, both sides wall upper portion has all opened vent 2 around holding case 1, be equipped with the filter screen in the vent 2, the inside wall upper portion rigid coupling that holds case 1 has spacing frame 3, the top of spacing frame 3 is provided with apron 4 through the bolt, spacing 3 downside holds and installs first damper 5 between the case 1 left and right sides wall, be equipped with second damper 6 in the first damper 5.

When the battery box is required to be used, a user can unscrew the bolt on the cover plate 4 through a tool, so that the fixing of the cover plate 4 can be released, then the user puts the battery pack into the second damping mechanism 6, then the user resets the cover plate 4, and the bolt is unscrewed and reset through the tool, so that the cover plate 4 can be fixed, and when the containing box 1 moves to generate distance shaking, the shaking of the battery pack in the containing box 1 can be buffered through the first damping mechanism 5 and the second damping mechanism 6.

As shown in fig. 4 and 5, the first damping mechanism 5 includes a first support rod 501, a second support rod 502, pneumatic springs 503, a connecting frame 504 and a damping frame 505, the damping frame 505 is disposed in the containing box 1 on the lower side of the limiting frame 3, the connecting frame 504 is disposed on the front and rear sides of the left and right side walls of the damping frame 505, two pneumatic springs 503 are rotatably mounted on the outer side walls of the four connecting frames 504, the first support rods 501 are mounted on the four pneumatic springs 503 on the upper side through bearings, the four first support rods 501 are respectively and fixedly connected to the upper portions of the left and right side walls in the containing box 1, the second support rods 502 are mounted on the four pneumatic springs 503 on the lower side through bearings, and the four second support rods 502 are respectively connected to the lower portions of the left and.

When the containing box 1 is greatly shaken back and forth, the pneumatic springs 503 have good high-frequency vibration absorption, the shaking amplitude of the damping frame 505 can be reduced by matching the eight pneumatic springs 503 with the corresponding connecting frames 504, meanwhile, the second damping mechanism 6 can damp the vibration through the eight pneumatic springs 503, and the second damping mechanism 6 can buffer the left and right or front and back shaking of the battery pack and reset the battery pack, so that the battery pack can be used in different regional environments through the invention.

Example 2

On the basis of embodiment 1, as shown in fig. 6, 7, 8, 9 and 10, the second damping mechanism 6 includes a fixing frame 601, a positioning frame 602, a fixing rod 603, a sliding frame 604, a first return spring 605, a second return spring 6051, a sliding rod 6052, a limiting block 606, a mounting frame 607, a heat dissipation frame 609 and a containing component, the containing component is disposed in the heat dissipation frame 609, the mounting frame 607 is mounted on both front and rear side walls of the heat dissipation frame 609 through bolts, both left and right sides of the mounting frame 607 are provided with chutes 608, the fixing frame 601 is mounted in the middle of both front and rear side walls in the shock dissipation frame 505, the positioning frame 602 is mounted on both inner side walls of the shock dissipation frame 505 on both left and right sides of the fixing frame 601, the fixing rod 603 is connected between the left and right adjacent positioning frames 602, the fixing rod 603 passes through the fixing frame 601, both left and right sides of the fixing rod 603 are slidably provided with the sliding frames, one end of a first reset spring 605 is connected with the corresponding locating rack 602, the other end of the first reset spring 605 is fixedly connected with the corresponding sliding rack 604, a fixing rod 603 between the left sliding rack 604 and the right sliding rack 604 is sleeved with two second reset springs 6051, the left and the right second reset springs 6051 are respectively located at the left and the right sides of the fixed rack 601, one end of each second reset spring 6051 is fixedly connected with the corresponding sliding rack 604, the other end of each second reset spring 6051 is fixedly connected with the fixed rack 601, a sliding rod 6052 is respectively installed in the middle of the inner side wall of the front sliding rack 604 and the middle of the back sliding rack 604, the front sliding rod 6052 and the back sliding rod 6052 respectively penetrate through the corresponding inclined slots 608, and the inner ends.

When the containing box 1 is greatly shaken left and right or up and down, the battery pack is shaken left and right or up and down along with the shaking, the battery pack can shake left and right or up and down to enable the containing part to shake left and right or up and down, the heat dissipation frame 609 can shake left and right or up and down to enable the mounting frames 607 at two sides to shake left and right or up and down, the left and right or up and down shaking of the mounting frames 607 can be buffered and reset through the matching of the first reset spring 605 and the second reset spring 6051, so that the shock absorption of the battery pack in the containing box 1 can be realized, meanwhile, the temperature generated by the battery pack can be dissipated through the heat dissipation frame 609, the overhigh temperature of the battery pack in the containing box 1 is avoided, when the battery pack in the containing box 1 needs to be replaced, a user repeatedly operates the cover plate 4 to open, and then the containing part is, and the battery pack is released from being fixed, then the user takes out and replaces the battery pack, and then the user fixes the battery pack through the containing part, and then the user repeats the above operation to reset and fix the cover plate 4.

As shown in fig. 9 and 10, the accommodating part includes a battery box 610, a box cover 611, a first handle 612, a connecting block 613 and a second handle 614, the battery box 610 is placed in a heat dissipation frame 609, the box cover 611 is installed on the top of the battery box 610 through a bolt, the first handle 612 is installed on the front side and the rear side of the box cover 611 through a bolt, the connecting block 613 is fixedly connected to both side walls in the battery box 610, and the second handle 614 is installed on the top of the connecting block 613 through a bolt.

When the battery box 610 is greatly shaken left and right or up and down, the battery pack is shaken left and right or up and down along with the battery pack, the battery pack can be shaken left and right or up and down along with the battery box 610, the heat dissipation frame 609 can be shaken left and right or up and down along with the battery box 610, the left and right or up and down shaking of the mounting frame 607 can be buffered and reset through the matching of the first return spring 605 and the second return spring 6051, when the battery pack needs to be replaced, a user repeats the operation to open the cover plate 4, then the user moves out the bolt on the box cover 611 through a tool, so that the fixation of the box cover 611 can be released, then the user moves out the box cover 611 through the first handle 612, so that the limitation on the battery pack can be released, then the user takes the battery box 610 out of the heat dissipation frame 609, the user replaces the battery pack in the battery box 610, then the user puts the battery box, the user resets the case cover 611 and fixes it by the bolt, and then the user repeats the above operation to reset and fix the cover 4.

Example 3

On the basis of the embodiment 2, as shown in fig. 10, fig. 11, fig. 12, fig. 13 and fig. 14, the utility model also comprises a connecting frame 7 and a sliding frame 8, sliding sleeve 9, kelly 10, bull stick 11, fixed disk 12, rolling disc 14 and sliding block 15, the rigid coupling has the slip frame 8 between two front and back connection frame 7, two front and back connection frame 7 communicate with slip frame 8 respectively, three sliding sleeve 9 is installed to the bottom in the connection frame 7, slidingtype is equipped with kelly 10 between three sliding sleeve 9, kelly 10 slidingtype passes battery box 610, kelly 10 and heat dissipation frame 609 slidingtype setting, the slidingtype is equipped with bull stick 11 in the slip frame 8, two fixed disks 12 are installed to the lower part of bull stick 11, arc wall 13 has all been opened to the both sides of fixed disk 12, rolling disc 14 is installed on the top of bull stick 11, sliding block 15 is all installed to the inner of two front and back kellies 10, two front and back sliding blocks 15 are the slidingtype setting respectively between two upper and.

When the battery pack needs to be replaced, the user repeats the above operations to open the battery box 610, after the battery box 610 is opened, the user rotates the rotating rod 11 counterclockwise through the rotating disc 14, the rotating rod 11 rotates counterclockwise to rotate the fixed disc 12 counterclockwise, the fixed disc 12 rotates counterclockwise through the matching of the arc-shaped grooves 13, so that the sliding blocks 15 on the front and rear sides are closed, the sliding blocks 15 on the front and rear sides are closed to close the clamping rods 10 on the front and rear sides, so that the clamping rods 10 on the front and rear sides are moved out of the heat dissipation frame 609, then the user moves out the connecting frame 7, so that the fixation of the battery box 610 can be released, then the user moves the battery box 610 out of the heat dissipation frame 609 through the second handle 614, then the user replaces the battery pack in the battery box 610, then the user resets the battery box 610, and resets the connecting frame 7, then the user rotates the rotating disc 14 clockwise, the fastening rods 10 at the front and rear sides are inserted into the heat-dissipating frame 609 so that the battery pack is fixed, and then the user repeats the above-described operation to reset and fix the case cover 611, and then repeats the above-described operation to reset and fix the cover plate 4.

As shown in fig. 15 and 16, still include fan 16, extension board 18, dwang 19, baffle 20 and torsional spring 21, four fan 16 are all installed to the front and back both sides of spacing frame 3, spacing frame 3 of fan 16 downside is opened there is the inlet scoop, at least five ventilation holes 17 have all been opened on the left and right sides wall upper portion in the spacing frame 3, two extension boards 18 are all installed to the spacing frame 3 inside wall of ventilation hole 17 front and back both sides, dwang 19 is installed to the rotary type between two corresponding extension boards 18, baffle 20 has been inlayed at the middle part of dwang 19, two upper and lower baffle 20 contact cooperations, the dwang 19 of baffle 20 front and back both sides all overlaps torsional spring 21, the one end of torsional spring 21 and the extension board 18 rigid coupling that corresponds, the other end of.

When the temperature in the battery box 610 is high, the fan 16 is started to work, the fan 16 works to extract the outside air, the air is pushed into the containing box 1 through the air suction opening, sundries can be blocked by the filter screen at the ventilation opening 2, the air entering the containing box 1 flows downwards along with the sundries, when the air in the containing box 1 flows into the damping frame 505, the air continues to flow, so that the baffles 20 at the upper and lower sides can swing to open the vent holes 17 through the flow of a large amount of air, the baffles 20 at the upper and lower sides can swing to rotate the rotating rod 19, the torsion spring 21 compresses along with the rotation of the rotating rod, the air flows out along with the torsion spring to complete circulation, through the continuous circulation of air and the cooperation of the heat dissipation frame 609, the temperature of the battery box 610 can be rapidly reduced, when the temperature of the battery box 610 is lowered, the user turns off the fan 16, and no large amount of air is pushed into the containing box 1, so that the damper 20 is restored by the torsion spring 21.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A lithium battery pack comprises a containing box (1), a limiting frame (3) and a cover plate (4), wherein ventilation openings (2) are formed in the upper portions of two side walls of the containing box (1), a filter screen is arranged in each ventilation opening (2), the limiting frame (3) is fixedly connected to the upper portion of the inner side wall of the containing box (1), the cover plate (4) is arranged at the top of each limiting frame (3) through bolts, the lithium battery pack is characterized by further comprising a first damping mechanism (5) and a second damping mechanism (6), the first damping mechanism (5) is arranged between the two side walls of the containing box (1) on the lower side of each limiting frame (3), and the second damping mechanism (6) is arranged in each first damping mechanism (5); first damper (5) are including first branch (501), second branch (502), pneumatic spring (503), link (504) and shock attenuation frame (505), shock attenuation frame (505) set up and hold case (1) at spacing (3) downside, link (504) are all installed to the both sides wall of shock attenuation frame (505), two pneumatic spring (503) are installed to the lateral wall rotary type of link (504), first branch (501) are installed through the bearing in pneumatic spring (503) of upside, both sides wall in holding case (1) of rigid coupling respectively in first branch (501), second branch (502) are installed through the bearing in pneumatic spring (503) of downside, both sides wall in holding case (1) of rigid coupling respectively in second branch (502).

2. The lithium battery pack as claimed in claim 1, wherein the second damping mechanism (6) comprises a fixing frame (601), a positioning frame (602), a fixing rod (603), a sliding frame (604), a first return spring (605), a second return spring (6051), a sliding rod (6052), a limiting block (606), a mounting frame (607), a heat dissipation frame (609) and a containing component, the containing component is arranged in the heat dissipation frame (609), the mounting frame (607) is mounted on both sides of the heat dissipation frame (609) through bolts, the mounting frame (607) is provided with two chutes (608), the fixing frame (601) is connected to the middle portions of both side walls in the shock dissipation frame (505), the positioning frames (602) are mounted on both side walls in the shock dissipation frame (505) on both sides of the fixing frame (601), the fixing rod (603) is connected between the two corresponding positioning frames (602), and the fixing rod (603) passes through the fixing frame (601), carriage (604) are all slidingly arranged on two sides of fixing rod (603), two first reset springs (605) are sleeved on the fixing rod (603) on the outer sides of the two carriages (604), one end of each first reset spring (605) is connected with the corresponding positioning frame (602), the other end of each first reset spring (605) is fixedly connected with the corresponding carriage (604), two second reset springs (6051) are sleeved on the fixing rod (603) between the two carriages (604), one end of each second reset spring (6051) is fixedly connected with the corresponding carriage (604), the other end of each second reset spring (6051) is fixedly connected with the fixing frame (601), sliding rods (6052) are arranged in the middles of the side walls of the carriages (604), four sliding rods (6052) are respectively slidingly arranged in the corresponding chutes (608), and limiting blocks (606) are arranged on the side walls of the sliding rods (6052).

3. The lithium battery pack as claimed in claim 2, wherein the holding member comprises a battery box (610), a box cover (611), a first handle (612), a connecting block (613) and a second handle (614), the battery box (610) is arranged in the heat dissipation frame (609), the box cover (611) is mounted at the top of the battery box (610) through bolts, the first handle (612) is arranged at two sides of the box cover (611) through bolts, the connecting block (613) is fixedly connected to two side walls in the battery box (610), and the second handle (614) is mounted at the top of the connecting block (613) through bolts.

4. The lithium battery pack as claimed in claim 3, further comprising connecting frames (7), sliding frames (8), sliding sleeves (9), clamping rods (10), rotating rods (11), fixed disks (12), rotating disks (14) and sliding blocks (15), wherein the sliding frames (8) are fixedly connected between the two connecting frames (7), three sliding sleeves (9) are installed at the bottom of the connecting frames (7), the clamping rods (10) are slidably arranged between the three sliding sleeves (9), the clamping rods (10) slidably penetrate through the battery box (610), the clamping rods (10) and the heat dissipation frames (609) are slidably arranged, the rotating rods (11) are slidably arranged in the sliding frames (8), the two fixed disks (12) are installed on the rotating rods (11), the two sides of the fixed disks (12) are provided with arc-shaped grooves (13), the rotating disks (14) are installed at the top ends of the rotating rods (11), the sliding blocks (15) are installed at the inner ends of the two clamping rods (10), the two sliding blocks (15) are respectively arranged between the upper and lower corresponding arc-shaped grooves (13) in a sliding manner.

5. The lithium battery pack as recited in claim 4, further comprising a fan (16), support plates (18), a rotating rod (19), a baffle (20) and a torsion spring (21), wherein four fans (16) are installed on both sides of the limit frame (3), an air suction opening is opened on the limit frame (3) at the lower side of the fan (16), a plurality of vent holes (17) are opened on both side walls in the limit frame (3), a plurality of vent holes (17) are opened on both side walls of the containing box (1), the limit frame (3) is relatively communicated with the vent holes (17) on the corresponding side of the containing box (1), two groups of support plates (18) are respectively arranged on both sides of the inner side wall of the limit frame (3) close to the vent holes (17), the two ends of the upper and lower groups of rotating rods (19) are rotatably installed between the support plates (18) opposite to both sides of the vent holes (17), two groups of baffles (20) are fixed in the middle of each rotating rod (19), and the baffles (20) ) The contact cooperation, all overlap on dwang (19) of baffle (20) both sides has torsional spring (21), the one end and the extension board (18) rigid coupling that corresponds of this torsional spring (21), the other end and the dwang (19) rigid coupling that corresponds of torsional spring (21).