Isostatic pressing graphite fuel bipolar plate cutting tool

Abstract

The utility model discloses an isostatic pressing graphite fuel bipolar plate cutting tool, including base, be provided with isostatic press outer frame on the base, vacuum pump, condenser and prestressed support frame, be provided with cutting assembly in isostatic press outer frame, be provided with vacuum valve above cutting assembly, vacuum pump is connected with vacuum valve, vacuum pump is connected with condenser, be provided with support air pressure pole on prestressed support frame, be provided with connecting rod on support air pressure pole, be connected with pressure telescopic link on connecting rod, pressure telescopic link is connected with vacuum valve, in the utility model, the modularized sealing unit of dovetail mechanical embedding is combined with two -stage sealing quick -coupling joint, can make cutting tool leakage rate reduce, effectively avoid the bipolar plate waste production caused by the sealing failure, improve product pass rate, through the cooperation of fastening bolt, PTFE modified silica gel sealing pad and sealing door, can according to the graphite plate material of different thickness, the compression of PTFE modified silica gel sealing pad is adjusted automatically.

Description

Technical Field

[0001] This utility model relates to the field of isostatic bipolar plates, and in particular to a cutting tooling for isostatic graphite fuel bipolar plates. Background Technology

[0002] With the booming development of the new energy vehicle industry, fuel cells have become an important development direction due to their high efficiency and environmental friendliness. As a core component of fuel cells, the manufacturing precision of isostatic graphite bipolar plates directly affects the overall performance of the fuel cell stack. The bipolar plate cutting process is a key step that determines its dimensional accuracy, sealing, and conductivity.

[0003] Currently, the sealing structures of commonly used isostatic pressing graphite bipolar plate cutting fixtures in the industry mostly employ continuous sealing strips combined with adhesive bonding, as disclosed in CN114654797A. In actual production, the isostatic pressing process generates a large amount of fine dust, which easily penetrates the sealing surface. This dust intrusion during hot pressing leads to wear on the sealing surface, increasing the vacuum leakage rate and consequently raising the bipolar plate scrap rate. This significantly increases production costs and reduces production efficiency.

[0004] In terms of maintenance efficiency, traditional tooling typically uses M12 threaded connections for pneumatic rods. Disassembly and replacement of the pneumatic rod require specialized tools and installation, making the process cumbersome and time-consuming. This results in significant annual downtime losses, impacting the company's economic benefits and production capacity.

[0005] Furthermore, existing tooling has significant limitations in adapting to sheet thickness. This results in poor edge sealing of the sheet material and increased edge leakage rate, which not only affects the quality of the bipolar plate but may also lead to a series of problems in subsequent assembly processes. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a cutting tool for isostatic graphite fuel bipolar plates, which can solve the problems of high leakage rate, poor sealing and accuracy of isostatic graphite bipolar plates.

[0007] To solve the above-mentioned technical problems, the solution of this utility model is as follows:

[0008] A tooling for cutting isostatic graphite fuel bipolar plates includes a base, an isostatic press outer frame, a condenser, and a prestressed support frame mounted on the base. A cutting assembly is located inside the isostatic press outer frame, and a vacuum valve is positioned above the cutting assembly. The vacuum valve is connected to a vacuum pump, which is connected to the condenser. A supporting air pressure rod is mounted on the prestressed support frame, and a connecting rod is mounted on the supporting air pressure rod. A pressure telescopic rod is connected to the connecting rod and is connected to the vacuum valve. The cutting assembly includes an outer frame and several sealing units located inside the outer frame. Adjacent sealing units are connected by a dovetail joint structure. Each sealing unit has an air passage, and a double-stage sealing quick-connect joint is provided at the connection of the air passage. A sealing door is located on the side of the isostatic press outer frame, and fastening bolts are evenly distributed around the sealing door. A PTFE modified silicone sealing gasket is located inside the sealing door.

[0009] The depth of the dovetail joint structure is 5-15mm.

[0010] The tenon bevel of the dovetail joint structure is 10-20°, and the radial gap after fitting is ≤0.15mm.

[0011] The dual-stage sealed quick connector is internally equipped with a fluororubber O-ring with a Shore hardness of 70 and a 304 stainless steel spring energy storage ring.

[0012] The pressure telescopic rod is connected to a sleeve-type connector, which is sleeved on the connecting rod.

[0013] The fastening bolts are M8 hydraulic compensating bolts, and at least four of them are provided.

[0014] The base has a limiting groove, and a lifting wheel is provided inside the limiting groove. The prestressed support frame is mounted on the lifting wheel.

[0015] The vacuum pump, condenser, pressure telescopic rod, and lifting wheel are connected to a PLC control system via sensors.

[0016] The lifting wheel includes a swivel wheel and a lifting rod mounted on the swivel wheel.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] In this invention, the modular sealing unit with dovetail tenon mechanical fitting, combined with a double-stage sealing quick-connect joint, reduces tooling leakage, effectively preventing bipolar plate defects due to seal failure and improving product qualification rate. Through the coordination of fastening bolts, PTFE modified silicone gaskets, and sealing doors, the compression of the PTFE modified silicone gasket can be automatically adjusted according to graphite sheet thicknesses, ensuring good sealing performance for sheets of varying thicknesses and improving bipolar plate production yield. The lifting wheels, integrated laser rangefinder, and PLC control system reduce tooling parallelism errors, ensuring dimensional accuracy, meeting high-precision cutting requirements, and guaranteeing bipolar plate processing quality. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of this utility model;

[0020] Figure 2 This is the front view of the present utility model;

[0021] Figure 3 This is a schematic diagram of the structure of the cutting assembly of this utility model;

[0022] Figure 4 This is a schematic diagram of the sealing unit of this utility model. Detailed Implementation

[0023] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. It should be noted that these descriptions are for the purpose of aiding understanding of this utility model, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0024] like Figure 1-4As shown, an isostatic pressing graphite fuel bipolar plate cutting fixture includes a base 1, an isostatic press outer frame 2, a condenser 4, and a prestressed support frame 5 mounted on the base 1. A cutting assembly 6 is installed inside the isostatic press outer frame 2, and a vacuum valve 7 is positioned above the cutting assembly 6. The vacuum valve 7 is connected to a vacuum pump 8, which is connected to the condenser 4. A supporting pneumatic rod 10 is mounted on the prestressed support frame 5, and a connecting rod 11 is mounted on the supporting pneumatic rod 10. A pressure telescopic rod 12 is connected to the connecting rod 11. Rod 12 is connected to vacuum valve 7. The cutting assembly 6 includes tooling outer frame 13 and several sealing units 14 disposed inside tooling outer frame 13. Adjacent sealing units 14 are connected by dovetail tenon-groove structure. Air passages 15 are provided on sealing units 14. Double-stage sealing quick connectors 16 are provided at the connection of air passages 15. Sealing doors 17 are provided on the side of isostatic press outer frame 2. Fastening bolts 18 are evenly arranged around the sealing door 17. PTFE modified silicone sealing gaskets are provided on the inner side of sealing door 17.

[0025] The depth of the dovetail joint is 5-15mm.

[0026] The tenon bevel of the dovetail joint structure is 10-20°, and the radial gap after fitting is ≤0.15mm.

[0027] The dovetail joint structure has a depth of 5-15mm and a bevel angle of 10-20°, resulting in a radial clearance ≤0.15mm after fitting. This structure not only facilitates the quick replacement of individual sealing units but also effectively prevents graphite dust from entering the sealing surface, improving sealing performance. In practical applications, using a dovetail depth of 8mm, a tenon bevel angle of 15°, and a groove width of 5mm, with a radial clearance ≤0.1mm after fitting, provides even better graphite protection.

[0028] The double-sealed quick-connector 16 is internally equipped with a fluororubber O-ring with a Shore hardness of 70 and a 304 stainless steel spring energy storage ring.

[0029] A dual-stage sealing quick-connector 16 is installed at the gas passage 15 interface. This connector incorporates a fluororubber O-ring with a Shore hardness of 70 and a 304 stainless steel spring accumulator ring, forming a composite sealing structure with a radial compression of 0.3 mm. The fluororubber O-ring has excellent sealing performance and wear resistance, while the spring accumulator ring can maintain sealing pressure during long-term use. Together, they achieve efficient sealing and prevent gas leakage.

[0030] A sleeve-type connector 19 is connected to the pressure telescopic rod 12, and the sleeve-type connector 19 is sleeved on the connecting rod 11. This configuration mainly facilitates the sleeved installation of the pressure telescopic rod 12.

[0031] The fastening bolts 18 are M8 hydraulic compensating bolts, and at least four are provided. The hydraulic compensating bolts are evenly distributed around the circumference of the sealing door of the outer frame. By rotating these bolts, the PTFE modified silicone gasket can be driven to achieve precise adjustment of the compression amount from 0.1 to 0.3 mm. The bolt stroke is linearly related to the gasket compression amount, which can automatically adjust the sealing pressure according to the graphite plate of different thicknesses to ensure the sealing effect.

[0032] A limiting groove 9 is provided on the base 1, and a lifting wheel is provided inside the limiting groove 9. The prestressed support frame 5 is set on the lifting wheel.

[0033] The vacuum pump 8, condenser 4, pressure telescopic rod 12, and lifting wheel are connected to a PLC control system 3 via sensors.

[0034] The lifting wheels include casters and lifting rods mounted on the casters. The limiting groove 9 is mainly for facilitating precise positioning of the lifting wheels. The lifting wheels facilitate the lifting and adjustment of the tooling of this utility model.

[0035] In this invention, the vacuum pump 8, condenser 4, pressure telescopic rod 12, and lifting wheel are connected to a PLC control system 3 via sensors. The parameters of each component are dynamically adjusted based on the data transmitted back from the sensors. Furthermore, in this invention, the sealing door 17 is a transparent sealing door, which facilitates observation.

[0036] In this invention, when a sealing unit in sealing unit 14 needs to be replaced, the operator presses the dovetail tenon to unlock it and applies a force of approximately 30N in the horizontal direction to slide out the faulty unit. When inserting the new sealing unit, the 15° inclination of the tenon generates a guiding force that automatically aligns it with the slot, enabling quick installation without the need for tedious operations such as cleaning residual adhesive. After starting the vacuum pump 3, the sensor collects vacuum data in real time and transmits it to the PLC control system. If the vacuum level does not reach the set value of -0.1MPa within 5 seconds, the PLC control system outputs a 4-20mA signal, increasing the vacuum pump speed by 20% and continuously adjusting until the set vacuum level is reached, ensuring a stable vacuum environment inside the tooling during the cutting process. After loading the graphite plate, the operator tightens the fastening bolt 18 clockwise and observes the PTFE modified silicone gasket compression scale line until it reaches the 0.3mm position. At this time, the sensor displays the gasket compression in real time, ensuring that the sealing pressure matches the plate thickness and achieving a good sealing effect. Before the tooling starts working, the electric lifting wheels are precisely adjusted to achieve automatic leveling of the tooling and ensure cutting accuracy.

[0037] In this invention, the modular sealing unit 14 with dovetail tenon mechanical fitting, combined with the double-stage sealing quick-connect joint 16, reduces tooling leakage rate, effectively preventing bipolar plate defects due to sealing failure and improving product qualification rate. Through the cooperation of the fastening bolts 18, the PTFE modified silicone gasket, and the sealing door 17, the compression amount of the PTFE modified silicone gasket can be automatically adjusted according to the graphite sheet thickness, ensuring good sealing performance for sheets of different thicknesses and improving bipolar plate production yield. The lifting wheels, integrated laser rangefinder, and PLC control system reduce tooling parallelism error, ensuring dimensional accuracy, meeting high-precision cutting requirements, and guaranteeing bipolar plate processing quality.

[0038] The embodiments of this utility model have been described in detail above with reference to the accompanying drawings, but this utility model is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of this utility model, and these variations still fall within the protection scope of this utility model.

Claims

1. A tooling for cutting isostatically pressed graphite fuel bipolar plates, characterized in that: The system includes a base (1), on which an isostatic press outer frame (2), a condenser (4), and a prestressed support frame (5) are mounted. Inside the isostatic press outer frame (2) is a cutting assembly (6), above which is a vacuum valve (7). The vacuum valve (7) is connected to a vacuum pump (8), which is connected to the condenser (4). A supporting pneumatic rod (10) is mounted on the prestressed support frame (5), and a connecting rod (11) is mounted on the supporting pneumatic rod (10). A pressure telescopic rod (12) is connected to the connecting rod (11). The pressure telescopic rod (12) is connected to... The vacuum valve (7) is connected, and the cutting assembly (6) includes a tooling outer frame (13) and a plurality of sealing units (14) disposed inside the tooling outer frame (13). Adjacent sealing units (14) are connected by a dovetail tenon-groove structure. The sealing unit (14) is provided with an air passage (15). The connection of the air passage (15) is provided with a double-stage sealing quick connector (16). The isostatic press outer frame (2) is provided with a sealing door (17) on its side. The sealing door (17) is evenly provided with fastening bolts (18) around its circumference. The sealing door (17) is provided with a PTFE modified silicone sealing gasket on its inner side.

2. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 1, characterized in that: The depth of the dovetail joint structure is 5-15mm.

3. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 1 or 2, characterized in that: The tenon bevel of the dovetail joint structure is 10-20°, and the radial gap after fitting is ≤0.15mm.

4. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 1, characterized in that: The double-sealed quick connector (16) is internally equipped with a fluororubber O-ring with a Shore hardness of 70 and a 304 stainless steel spring energy storage ring.

5. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 1, characterized in that: The pressure telescopic rod (12) is connected to a sleeve-type connector (19), which is sleeved on the connecting rod (11).

6. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 1, characterized in that: The fastening bolts (18) are M8 hydraulic compensation bolts, and at least four of them are provided.

7. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 1, characterized in that: The base (1) has a limiting groove (9) and a lifting wheel is provided inside the limiting groove (9). The prestressed support frame (5) is set on the lifting wheel.

8. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 7, characterized in that: The vacuum pump (8), condenser (4), pressure telescopic rod (12) and lifting wheel are connected to a PLC control system (3) via sensors.

9. The isostatic pressing graphite fuel bipolar plate cutting tooling according to claim 7, characterized in that: The lifting wheel includes a swivel wheel and a lifting rod mounted on the swivel wheel.

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