Formation device for soft package battery

Abstract

The utility model discloses a formation device for a soft package battery, the formation device for the soft package battery comprises a rack, a pre-pressing mechanism, a pressurizing mechanism and a transmission mechanism, the pre-pressing mechanism and the pressurizing mechanism are respectively positioned at two ends of the rack; the transmission mechanism pulls the pre-pressing mechanism to move back and forth in the length direction of the rack. The transmission mechanism comprises a first pre-tightening chain and a chain adjusting piece, the chain adjusting piece is connected with the pre-pressing mechanism, and the chain adjusting piece adjusts and keeps the tension degree of the first pre-tightening chain in the moving process of the pre-pressing mechanism.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery processing equipment, and in particular relates to a formation device for soft-pack batteries. Background Art

[0002] The soft-pack battery formation device is a device used in the production process of soft-pack batteries. Its main function is to perform formation treatment on soft-pack batteries. Formation refers to improving the performance and stability of batteries through specific chemical reactions under certain conditions (such as high temperature, high pressure, etc.). The formation treatment of soft-pack batteries is achieved by precisely controlling parameters such as temperature and pressure. The formation process of soft-pack batteries has an important influence on the performance of the final battery, and can effectively improve the cycle life and charge and discharge performance of the battery, and improve the safety of the battery. Therefore, the formation process occupies a vital position in the production of soft-pack batteries, and the formation device is one of the indispensable key equipment on the soft-pack battery production line.

[0003] The pressure of the formation equipment on the traditional market usually does not exceed 10T, and there is a problem of poor stability when providing pressure over a long stroke, which makes it difficult to meet the requirements of the formation process equipment for soft-pack batteries. Utility Model Content

[0004] The purpose of the utility model is to solve the technical problem that the pressure of the formation device on the traditional market usually does not exceed 10T, there is a problem that the pressure cannot be provided for a long stroke, and it is difficult to meet the requirements of the formation process equipment of the soft-pack battery, and to provide a formation device for soft-pack batteries.

[0005] In order to solve the above problems, the utility model is implemented according to the following technical solutions:

[0006] The utility model provides a formation device for a soft-pack battery, the formation device for a soft-pack battery comprises a frame, a pre-pressing mechanism, a pressurizing mechanism and a transmission mechanism, the pre-pressing mechanism and the pressurizing mechanism are respectively located at two ends of the frame, and the transmission mechanism pulls the pre-pressing mechanism to move back and forth along the length direction of the frame;

[0007] The transmission mechanism comprises a first pre-tensioning chain and a chain adjusting member, wherein the chain adjusting member is connected to the pre-pressing mechanism, and the chain adjusting member adjusts and maintains the tension of the first pre-tensioning chain during the movement of the pre-pressing mechanism.

[0008] The transmission mechanism comprises:

[0009] A sprocket structure, wherein the two sprocket structures are relatively arranged at two ends of the pre-pressing mechanism and the pressing mechanism, and the sprocket structure is connected to the first pre-tightening chain;

[0010] A first driving assembly and a driving assembly bracket, wherein the first driving assembly is fixedly connected to the pre-pressing mechanism through the driving assembly bracket;

[0011] A transmission shaft is passed through the first driving assembly and connected to the sprocket structure.

[0012] The sprocket structure comprises:

[0013] A driven sprocket, the driven sprocket having a cavity and sprocket teeth arranged outside the cavity, the sprocket teeth of the driven sprocket being connected to the first pre-tightening chain;

[0014] A rolling bearing assembly, wherein the rolling bearing assembly is disposed in a cavity of the driven sprocket;

[0015] A sprocket fixing frame, wherein the sprocket fixing frame has a through hole, and a plurality of the sprocket fixing frames are respectively connected to the pre-pressing mechanism and the pressurizing mechanism;

[0016] A sprocket fixing shaft is passed through the through hole of the sprocket fixing frame and is connected to the rolling bearing assembly.

[0017] The frame comprises:

[0018] a first guide post and a second guide post, wherein the first guide post has a groove, and the plurality of second guide posts are disposed on both sides of the sprocket structure;

[0019] A layer plate assembly and a second pre-tightening chain, a plurality of the layer plate assemblies are connected by the second pre-tightening chain, and the layer plate assembly moves back and forth along the first guide column along with the movement of the pre-pressing mechanism and the pressurizing mechanism.

[0020] The pre-pressing mechanism comprises:

[0021] A first side plate, wherein the first side plate is provided with a bearing assembly, the bearing assembly is connected to the transmission shaft and the first driving assembly, and the first side plate is connected to the first guide column and the second guide column;

[0022] A support member and a locking assembly, wherein the support member controls the displacement of the layer assembly toward the pressurizing mechanism through the locking assembly.

[0023] The pressurizing mechanism comprises:

[0024] a second drive assembly;

[0025] A push plate assembly, wherein the push plate assembly controls the displacement of the layer plate assembly toward the pre-pressing mechanism through the second driving assembly.

[0026] a second side plate, the second side plate connecting the second driving assembly and the push plate assembly;

[0027] The push plate assembly includes a pressurizing member, a first pressure adapter connected to the pressurizing member in sequence, a polyurethane plate, a second pressure adapter, a push plate, a partition plate and a heat insulating member.

[0028] The rolling bearing assembly comprises a first rolling bearing, a bearing pad, a second rolling bearing and an elastic retaining ring for a hole, wherein the first rolling bearing, the bearing pad, the second rolling bearing and the elastic retaining ring for a hole are arranged in sequence along the length direction of the sprocket fixing shaft.

[0029] The locking assembly comprises:

[0030] A third driving assembly, wherein the two third driving assemblies are arranged oppositely at two ends of the first side plate;

[0031] A positioning rack, the positioning rack being placed in a groove of the first guide column;

[0032] A locking slide, wherein the locking slide has teeth adapted to the positioning rack, thereby achieving the positioning of the layer plate assembly in the first guide column.

[0033] The second driving component integrates a motor, a reducer, an encoder and a driver. The driver realizes position control of the motor through the encoder, and the reducer controls the output speed and output torque of the motor.

[0034] Compared with the prior art, the beneficial effects of the utility model are:

[0035] A formation device for a soft-pack battery, comprising a frame, a pre-pressing mechanism, a pressurizing mechanism and a transmission mechanism, wherein the pre-pressing mechanism and the pressurizing mechanism are respectively located at two ends of the frame, and the transmission mechanism pulls the pre-pressing mechanism to move back and forth along the length direction of the frame; the transmission mechanism comprises a first pre-tightening chain and a chain adjusting member, wherein the chain adjusting member is connected to the pre-pressing mechanism, and the chain adjusting member adjusts and maintains the tension of the first pre-tightening chain during the movement of the pre-pressing mechanism.

[0036] This study achieved the formation process of soft-pack batteries under a pressure of 40 tons. The pressure of traditional formation processes is usually no more than 10T. This device adopts a dual pressure adjustment mechanism of a pre-pressing mechanism and a pressurizing mechanism to pressurize the layer plate assembly where the soft-pack batteries are placed. The addition of a transmission structure significantly improves the stability of the pre-pressing mechanism when providing pressure, avoiding unnecessary damage to the battery due to shaking. The combination of the three realizes high-temperature formation of ultra-high pressure soft-pack batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings, wherein:

[0038] Figure 1 It is a three-dimensional schematic diagram of a formation device for soft-pack batteries of the utility model;

[0039] Figure 2 It is a partial enlarged view of the utility model;

[0040] Figure 3 It is a structural schematic diagram of the transmission mechanism of the utility model;

[0041] Figure 4 It is a three-dimensional schematic diagram of the transmission and positioning rack of the utility model;

[0042] Figure 5 It is a structural schematic diagram of the layer plate assembly of the utility model;

[0043] Figure 6 It is a structural schematic diagram of the push plate assembly of the utility model;

[0044] Figure 7 It is a structural schematic diagram of the pre-pressing mechanism of the utility model;

[0045] In the figure: frame-10; first guide column-11; second guide column-12; layer plate assembly-13; second pre-tightening chain-14;

[0046] Pre-pressing mechanism-20; first side plate-21; support member-22; locking assembly-23; third driving assembly-231; positioning rack-232; locking slide-233;

[0047] Pressurizing mechanism-30; second driving assembly-31; push plate assembly-32; second side plate-33;

[0048] Transmission mechanism-40; first pre-tightening chain-41; chain adjusting member-42; sprocket structure-43; driven sprocket-431; rolling bearing assembly-432; sprocket fixing frame-433; sprocket fixing shaft-434; first driving assembly-44; driving assembly bracket-45; transmission shaft-46. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0050] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0051] like Figure 1 to Figure 7 As shown, the utility model is a formation device for soft-pack batteries, which includes a frame 10, a pre-pressing mechanism 20, a pressurizing mechanism 30 and a transmission mechanism 40. The pre-pressing mechanism 20 and the pressurizing mechanism 30 are respectively located at both ends of the frame 10, and the transmission mechanism 40 pulls the pre-pressing mechanism 20 to move back and forth along the length direction of the frame 10; the transmission mechanism 40 includes a first pre-tightening chain 41 and a chain adjusting member 42, the chain adjusting member 42 is connected to the pre-pressing mechanism 20, and the chain adjusting member 42 adjusts and maintains the tension of the first pre-tightening chain 41 during the movement of the pre-pressing mechanism 20.

[0052] Preferably, the transmission mechanism 40 includes a belt drive, which transmits power through a belt made of materials such as rubber or polyurethane, and is used in formation devices for soft-pack batteries that require shock absorption, noise reduction and a relatively large transmission ratio.

[0053] Gear transmission, gear transmission uses the meshing of gears to transmit power and motion. Gears include spur gears, helical gears, worm gears, etc.

[0054] Pulley drive: Pulley drive uses the friction between the belt and the pulley to transmit power. It is used in the formation device of soft-pack batteries that require smooth transmission and speed regulation functions.

[0055] Hydraulic transmission: Hydraulic transmission uses hydraulic components (such as hydraulic pumps, hydraulic cylinders, etc.) to transmit power. It has the advantages of smooth transmission and high energy transfer efficiency. It is used in heavy-load, high-precision soft-pack battery formation devices.

[0056] The transmission mechanism 40 of the present device is preferably a pneumatic transmission, which utilizes compressed air to transmit power and realizes motion control through pneumatic components (such as cylinders, pneumatic valves, etc.).

[0057] The transmission mechanism 40 includes a sprocket structure 43, and the two sprocket structures 43 are relatively arranged at the two ends of the pre-pressing mechanism 20 and the pressurizing mechanism 30, and the sprocket structure 43 is connected to the first pre-tensioning chain 41; a first driving component 44 and a driving component bracket 45, and the first driving component 44 is fixedly connected to the pre-pressing mechanism 20 through the driving component bracket 45; a transmission shaft 46, and the transmission shaft 46 is passed through the first driving component 44 and connected to the sprocket structure 43.

[0058] Specifically, the first driving component 44 includes electrical equipment of different types and specifications, such as a DC motor, an AC asynchronous motor, an AC synchronous motor, and a stepping motor.

[0059] The sprocket structure 43 includes a driven sprocket 431, which has a cavity and sprocket teeth arranged outside the cavity, and the sprocket teeth of the driven sprocket 431 are connected to the first preload chain; a rolling bearing assembly 432, which is arranged in the cavity of the driven sprocket 431; a sprocket fixing frame 433, which has a through hole, and a plurality of sprocket fixing frames 433 are respectively connected to the preload mechanism 20 and the pressurizing mechanism 30, and a sprocket fixing shaft 434, which is passed through the through hole of the sprocket fixing frame 433 and connected to the rolling bearing assembly 432. The rolling bearing assembly 432 includes a first rolling bearing, a bearing pad, a second rolling bearing and a hole elastic retaining ring, and the first rolling bearing, the bearing pad, the second rolling bearing and the hole elastic retaining ring are arranged in sequence along the length direction of the sprocket fixing shaft 434.

[0060] Preferably, the sprocket structure 43 includes an elastic retaining ring for the shaft, a sprocket tensioning adjustment block, a flat washer, a spring washer and a nut; the sprocket fixing shaft 434 passes through the through hole of the sprocket fixing frame 433 and is connected to the driven sprocket 431, the rolling bearing assembly 432, the elastic retaining ring for the shaft, the sprocket tensioning adjustment block, the flat washer, the spring washer and the nut.

[0061] The frame 10 includes a first guide column 11 and a second guide column 12, the first guide column 11 has a groove, and multiple second guide columns 12 are arranged on both sides of the sprocket structure 43; a layer plate assembly 13 and a second pre-tensioning chain 14, multiple layer plate assemblies 13 are connected by the second pre-tensioning chain 14, and the layer plate assembly 13 moves back and forth along the first guide column 11 with the movement of the pre-pressing mechanism 20 and the pressing mechanism 30.

[0062] Specifically, the frame 10 is provided with four first guide columns 11 distributed in a square shape and four second guide columns 12 distributed in a square shape are arranged around the first guide columns 11 at intervals.

[0063] Preferably, the layer plate assembly 13 includes an aluminum layer plate, a silicone sheet, a sensitive element, a tubular electric heating element, a stud, a layer plate hanging seat assembly, a guide fixing block, a card plate, a circuit board, a converter, a heat insulation plate, a layer plate fixing piece and a gasket; wherein the aluminum layer plate is connected to the silicone sheet, and a plurality of tubular electric heating elements are sequentially arranged along the length direction of the aluminum layer plate between the aluminum layer plate and the silicone sheet, the tubular electric heating element includes a body and an end portion, the structure of the body is preferably cylindrical, the shape of the end portion is preferably L-shaped, the two ends are spaced and connected in parallel to one end of the body, the sensitive element and the stud are spaced and arranged between the two ends, the sensitive element is preferably a thermistor, and the two layer plate hanging seat assemblies are The parts are arranged at both ends of the aluminum layer, and the aluminum layer is connected to the layer fixing parts through a guide fixing block. The shape of the layer fixing parts is preferably U-shaped, the circuit board is preferably a PCB board, and the circuit board is fixedly connected to the aluminum layer through a clamping plate. One end of the circuit board has a groove, and the converter is arranged in the groove. The structure of the converter is preferably Y-shaped, and the heat insulation board is arranged between the layer hanger assembly and the aluminum layer. The layer hanger assembly has a cavity, and the cavity of the layer hanger assembly is adapted to the guide column. One end of the cavity of the layer hanger assembly is connected to the gasket. The material of the gasket is preferably Teflon. The layer hanger assembly includes a layer hanger and a guide sleeve, and the layer hanger is connected to the second preload chain through a pin.

[0064] The pre-pressing mechanism 20 includes a first side plate 21, which is provided with a bearing assembly, the bearing assembly is connected to the transmission shaft 46 and the first driving assembly 44, the first side plate 21 is connected to the first guide column 11 and the second guide column 12; a support member 22 and a locking assembly 23, the support member 22 controls the displacement of the layer assembly 13 toward the direction of the pressurizing mechanism 30 through the locking assembly 23.

[0065] Preferably, the bearing assembly includes a coupling, a bearing base, and an outer spherical vertical seat bearing bolted to the bearing base, and the transmission shaft 46 passes through the outer spherical vertical seat bearing and is connected to the sprocket structure 43 and the coupling.

[0066] The two transmission shafts 46 are connected by a coupling, and the coupling connects the ends of the two shafts to transmit torque and rotational motion, and then transmits torque through the meshing between the sprocket teeth of the driven sprocket 431 and the first preload chain 41 to push the preload mechanism 20 to pressurize, and transfer power from one shaft to another. The first preload chain 41 is used to transmit larger torque and power, and is suitable for devices that need to transmit force and motion over long distances. In conjunction with the chain adjustment member 42, the preload mechanism 20 that provides ultra-high pressure over a long stroke is not prone to violent shaking, which improves the working efficiency of the formation device and meets the higher requirements of the soft-pack battery formation process.

[0067] The locking assembly 23 includes a third drive assembly 231, and two third drive assemblies 231 are relatively arranged at the two ends of the first side plate 21; a positioning rack 232, and the positioning rack 232 is placed in the groove of the first guide column 11; and a locking slide 233, and the locking slide 233 has teeth that are compatible with the positioning rack 232, thereby realizing the positioning of the layer assembly 13 in the first guide column 11.

[0068] Specifically, the third driving component 231 includes electrical equipment of different types and specifications, such as a DC motor, an AC asynchronous motor, an AC synchronous motor, and a stepping motor.

[0069] The positioning rack 232 is used to achieve precise positioning in the process of providing pressure. The positioning rack 232 has higher precision and stability to ensure accurate position control during the movement of the device. The positioning rack 232 cooperates with the teeth of the locking slide 233 and the third drive assembly 231 to achieve precise position adjustment and positioning functions.

[0070] The locking slide 233 is used for fixing or locking. The locking slide 233 can be locked in a specific position through the third driving assembly 231 to prevent the support member 22 from loosening or shifting during the movement. The locking slide 233 can achieve the locking function through threads, hydraulics, pneumatics, etc.

[0071] The positioning rack 232 is used for precise position control, while the locking slide 233 is used to ensure the stability and safety of the components.

[0072] The pressurizing mechanism 30 includes a second driving assembly 31; a push plate assembly 32, which controls the displacement of the layer assembly 13 toward the pre-pressing mechanism 20 through the second driving assembly 31. A second side plate 33, which connects the second driving assembly 31 and the push plate assembly 32; the push plate assembly 32 includes a pressurizing member, a first pressure adapter connected to the pressurizing member in sequence, a polyurethane plate, a second pressure adapter, a push plate, a partition and a heat insulating member. The second driving assembly 31 integrates a motor, a reducer, an encoder and a driver. The driver realizes the position control of the motor through the encoder, and the reducer controls the output speed and output torque of the motor.

[0073] The second drive assembly 31 is preferably a servo cylinder, which realizes precise position control through precision motors and drivers, can realize precise positioning on a scale of millimeters or even smaller, and maintain high repeatability. The servo cylinder can realize fast and smooth linear motion, has a fast response speed, and is suitable for applications of high-speed motion and rapid positioning. The servo cylinder can be programmed and controlled according to demand, and can flexibly adjust parameters such as speed, acceleration, position, etc., and is suitable for formation devices with different needs. The servo cylinder can usually use energy more efficiently, reduce energy waste and environmental pollution. The servo cylinder usually has a long service life and does not require frequent replacement and maintenance of seals, reducing maintenance costs and downtime. The servo cylinder monitors the motion state through built-in sensors, can realize safe stopping and anti-collision functions, and improve the safety of equipment and operators. The servo cylinder has many advantages such as high precision, high speed, flexibility, energy saving and environmental protection, simple maintenance and safety, and is suitable for linear motion control formation devices that require high precision, high speed and intelligent control.

[0074] For other structures of the formation device for soft-pack batteries described in this embodiment, refer to the prior art.

[0075] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Therefore, any modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A formation device for soft pack batteries, characterized in that: The formation device for soft-pack batteries comprises a frame (10), a pre-pressing mechanism (20), a pressurizing mechanism (30) and a transmission mechanism (40), wherein the pre-pressing mechanism (20) and the pressurizing mechanism (30) are respectively located at two ends of the frame (10), and the transmission mechanism (40) pulls the pre-pressing mechanism (20) to move back and forth along the length direction of the frame (10); The transmission mechanism (40) comprises a first pre-tensioning chain (41) and a chain adjusting member (42), wherein the chain adjusting member (42) is connected to the pre-stressing mechanism (20), and the chain adjusting member (42) adjusts and maintains the tension of the first pre-stressing chain (41) during the movement of the pre-stressing mechanism (20).

2. The formation device for soft pack batteries according to claim 1, characterized in that: The transmission mechanism (40) comprises: A sprocket structure (43), wherein two sprocket structures (43) are arranged at two ends of the pre-pressing mechanism (20) and the pressurizing mechanism (30) in a relative manner, and the sprocket structure (43) is connected to the first pre-tightening chain (41); A first driving assembly (44) and a driving assembly bracket (45), wherein the first driving assembly (44) is fixedly connected to the pre-pressing mechanism (20) via the driving assembly bracket (45); A transmission shaft (46), wherein the transmission shaft (46) passes through the first driving assembly (44) and is connected to the sprocket structure (43).

3. The formation device for soft pack batteries according to claim 2, characterized in that: The sprocket structure (43) comprises: A driven sprocket (431), the driven sprocket (431) having a cavity and sprocket teeth arranged outside the cavity, the sprocket teeth of the driven sprocket (431) being connected to the first pre-tightening chain; A rolling bearing assembly (432), wherein the rolling bearing assembly (432) is disposed in a cavity of the driven sprocket (431); A sprocket fixing frame (433), wherein the sprocket fixing frame (433) has a through hole, and a plurality of the sprocket fixing frames (433) are respectively connected to the pre-pressing mechanism (20) and the pressurizing mechanism (30); A sprocket fixing shaft (434), wherein the sprocket fixing shaft (434) is passed through a through hole of the sprocket fixing frame (433) and is connected to the rolling bearing assembly (432).

4. The formation device for soft pack batteries according to claim 3, characterized in that: The rolling bearing assembly (432) comprises a first rolling bearing, a bearing pad, a second rolling bearing and a hole elastic retaining ring, wherein the first rolling bearing, the bearing pad, the second rolling bearing and the hole elastic retaining ring are arranged in sequence along the length direction of the sprocket fixing shaft (434).

5. The formation device for soft pack batteries according to claim 2, characterized in that: The frame (10) comprises: A first guide column (11) and a second guide column (12), wherein the first guide column (11) has a groove, and a plurality of the second guide columns (12) are arranged on both sides of the sprocket structure (43); A layer plate assembly (13) and a second pre-tensioning chain (14), wherein a plurality of the layer plate assemblies (13) are connected via the second pre-tensioning chain (14), and the layer plate assembly (13) moves back and forth along the first guide column (11) along with the movement of the pre-pressing mechanism (20) and the pressurizing mechanism (30).

6. The formation device for soft pack batteries according to claim 5, characterized in that: The pressurizing mechanism (30) comprises: A second drive assembly (31); A push plate assembly (32), wherein the push plate assembly (32) controls the displacement of the layer plate assembly (13) toward the pre-pressing mechanism (20) through the second driving assembly (31); A second side plate (33), wherein the second side plate (33) connects the second driving assembly (31) and the push plate assembly (32).

7. The formation device for soft pack batteries according to claim 6, characterized in that: The push plate assembly (32) comprises a pressurizing member, a first pressure adapter connected to the pressurizing member in sequence, a polyurethane plate, a second pressure adapter, a push plate, a partition and a heat insulating member.

8. The formation device for soft pack batteries according to claim 6, characterized in that: The second driving component (31) integrates a motor, a reducer, an encoder and a driver. The driver realizes position control of the motor through the encoder, and the reducer controls the output speed and output torque of the motor.

9. The formation device for soft pack batteries according to claim 5, characterized in that: The pre-pressing mechanism (20) comprises: A first side plate (21), wherein the first side plate (21) is provided with a bearing assembly, wherein the bearing assembly is connected to the transmission shaft (46) and the first drive assembly (44), and the first side plate (21) is connected to the first guide column (11) and the second guide column (12); A support member (22) and a locking assembly (23), wherein the support member (22) controls the displacement of the layer assembly (13) toward the pressurizing mechanism (30) through the locking assembly (23).

10. The formation device for soft pack batteries according to claim 9, characterized in that: The locking assembly (23) comprises: A third driving assembly (231), wherein two third driving assemblies (231) are arranged opposite to each other at two ends of the first side plate (21); A positioning rack (232), the positioning rack (232) being placed in a groove of the first guide column (11); A locking slide (233), wherein the locking slide (233) has teeth that match the positioning rack (232), thereby achieving the positioning of the layer plate assembly (13) in the first guide column (11).

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