A clamping tool and method for gluing and connecting metal bipolar plates of fuel cells

Abstract

A clamping tool and method for gluing metal bipolar plates of fuel cells, wherein the clamping tool includes a positioning device, a heating device, and a vibration device. The positioning device includes an upper tool cover, a lower tool bottom plate, a positioning pin, and a first suction nozzle. The vibration device includes a vibration source, a vibration conductor, and a second suction nozzle. The upper tool cover and the lower tool bottom plate have built-in heating devices. The upper tool cover is provided with a vibration conductor, the upper end of which is connected to the vibration source and the lower end is connected to the second suction nozzle. The lower tool bottom plate is provided with a vacuum channel, the upper end of which is connected to the first suction nozzle and the lower end is connected to the side of the lower tool bottom plate. The upper tool cover and the lower tool bottom plate are used to clamp the metal bipolar plate, and the metal bipolar plate is clamped once to avoid the risk of plate dislocation caused by secondary clamping, simplifying the initial clamping process of the metal bipolar plate. The forming process adopts fully automatic flow, which simplifies the overall process and avoids the occurrence of plate warping and deformation caused by the original laser welding.

Description

Technical Field

[0001] The invention belongs to the technical field of tooling and fixtures, and in particular relates to a clamping tool and method for adhesively connecting metal bipolar plates of fuel cells. Background Art

[0002] Fuel cells generate electricity through electrochemical reactions between hydrogen and oxygen, and the final product is water. They are an important part of the current pollution-free, zero-emission new energy. Existing metal bipolar plates are mainly connected by laser welding of the anode monopolar plate and the cathode monopolar plate to form a "two plates and three fields" structure.

[0003] The existing laser welding processing method cannot be implemented on a single tooling plate because the field path will form a closed loop. When making welding tools, at least two weldings are required to achieve it. This method requires secondary clamping of the metal bipolar plate during welding, which affects the positioning and working time, and is inefficient. In addition, due to uneven thermal shrinkage in the area where laser welding is completed, the metal bipolar plate that has been laser welded will be irregularly warped. The degree of warping increases with the increase in the outer size of the metal bipolar plate, which seriously affects the reliability of the subsequent stacked assembly of the metal bipolar plate; laser welding causes surface oxidation, which increases the difficulty of preparing the surface coating; it is also prone to cold welding, which seriously restricts the yield rate. Summary of the invention

[0004] In view of the above problems, the present invention provides a clamping tool for adhesively connecting metal bipolar plates of fuel cells.

[0005] The object of the present invention can be achieved by the following technical solution: A clamping tool for adhesive connection of metal bipolar plates of fuel cells, comprising a positioning device, a heating device, and a vibration device;

[0006] The positioning device includes a tooling upper cover plate, a tooling lower base plate, a positioning pin, and a first suction nozzle, and the vibration device includes a vibration source, a vibration conductor, and a second suction nozzle;

[0007] The tooling upper cover plate and the tooling lower base plate are both equipped with built-in heating devices;

[0008] The bottom surface of the tooling upper cover plate is provided with a first tooling convex rib corresponding to the field path on the metal double-stage plate and a plurality of positioning pin holes located around the first tooling convex rib, and a plurality of vibration conductors are penetrated on the tooling upper cover plate, the upper end of the vibration conductor is connected to the vibration source, and the lower end extends to the first tooling convex rib and is connected to the second suction nozzle;

[0009] A second tooling rib corresponding to the field path on the metal double-stage plate and a plurality of positioning pins located around the second tooling rib are provided on the top surface of the tooling lower bottom plate, and a plurality of vacuum channels are provided on the tooling lower bottom plate, the upper ends of the vacuum channels are connected to the second tooling rib and are connected to the first suction nozzle, and the lower ends of the vacuum channels are connected to the side surfaces of the tooling lower bottom plate.

[0010] Furthermore, the heating device includes a heating tube, and the upper tooling cover plate and the lower tooling bottom plate are provided with heating tube grooves corresponding to the heating tube. Furthermore, the upper tooling cover plate is formed by connecting two first tooling plates stacked up and down, and the adjacent surfaces of the two first tooling plates are provided with a plurality of first heating tube grooves with semicircular cross sections correspondingly, and the lower tooling bottom plate is formed by connecting two second tooling plates stacked up and down, and the adjacent surfaces of the two second tooling plates are provided with a plurality of second heating tube grooves with semicircular cross sections correspondingly. Furthermore, the lower end of the vacuum channel on the lower tooling bottom plate leads to the side of the second tooling plate located below.

[0011] Furthermore, the vibration source is installed on the top surface of the tooling upper cover plate.

[0012] Furthermore, the positioning device also includes a vacuum pump, which is connected to the lower ends of the plurality of vacuum channels on the bottom plate of the tooling through an air pipe. Furthermore, the positioning device also includes an air pipe joint, which is installed at the lower end of the vacuum channel on the bottom plate of the tooling.

[0013] A method for gluing and connecting metal bipolar plates of a fuel cell, using the above-mentioned clamping tool, comprises the following steps:

[0014] (1) Place a monopolar plate on the top surface of the bottom plate of the tooling, so that its periphery is limited by the positioning pins and its plate surface is vacuum-adsorbed by the first suction nozzle to complete the posture fixation;

[0015] (2) Applying glue to the bonding area of ​​the monopolar plate on the bottom plate of the tooling;

[0016] (3) Place another monopolar plate on the monopolar plate on the lower bottom plate of the tooling, and the upper cover plate of the tooling cooperates with the lower bottom plate of the tooling to clamp the two monopolar plates;

[0017] (4) The heating rod heats the glue to cure quickly, and the vibration source drives the second suction nozzle to vibrate for a certain period of time through the vibration conductor and then stops;

[0018] (5) The upper cover plate and the lower bottom plate of the tooling are kept under pressure for a certain period of time and then released, and the first suction nozzle is released from adsorption.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The metal bipolar plate is clamped by the tooling upper cover plate and the tooling lower base plate, which can be clamped once to avoid the risk of plate dislocation caused by secondary clamping, simplifying the initial clamping process of the metal bipolar plate. The forming process adopts a fully automatic flow, simplifying the overall process;

[0021] (2) Since metal bipolar plates are flexible ultra-thin plates that are easy to deform and difficult to position, the positioning device uses positioning pins to position the plates, and adds suction cups on the glue coating path for vacuum adsorption to ensure that the plates are fixed in position, thus avoiding the warping and deformation of the plates caused by the original laser welding.

[0022] (3) When the tooling upper cover plate and the tooling lower bottom plate clamp the metal bipolar plate, the heating tubes built into the tooling lower bottom plate and the tooling upper cover plate can accelerate the curing of the glue. The vibration device set on the tooling upper cover plate can vibrate out the air in the glue to avoid bubbles in the glue during the curing process. The tooling upper cover plate and the tooling lower bottom plate also maintain pressure for a certain period of time to ensure the reliability of the adhesive connection of the metal bipolar plate.

[0023] (4) The metal bipolar plates are connected by adhesive bonding, which does not involve heat input and therefore does not cause deformation or surface oxidation problems, making it more conducive to the preparation of coatings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the clamping tool of the present invention;

[0025] Figure 2 A cross-sectional view of the clamping tool of the present invention when applied to the adhesive connection of metal bipolar plates;

[0026] Figure 3 A cross-sectional view of an upper cover plate and an upper component of a clamping tool of the present invention;

[0027] Figure 4 It is a schematic diagram of the arrangement of the second heating tube groove on the second fixture plate in the clamping fixture of the present invention;

[0028] Figure 5 A cross-sectional view of a fixture lower base plate and an upper component thereof in the clamping fixture of the present invention;

[0029] Figure 6 It is a schematic diagram of the arrangement of the positioning pins on the lower base plate of the clamping tool of the present invention.

[0030] The reference numerals are as follows:

[0031] 1. Tooling upper cover

[0032] 2. Tooling lower base plate

[0033] 3 positioning pins

[0034] 4First nozzle

[0035] 5. Trachea connector

[0036] 6The first tooling rib

[0037] 7 Dowel pin holes

[0038] 8 Second heating tube slot

[0039] 9 The second tooling rib

[0040] 10 Heating tube

[0041] 11. Vibration Source

[0042] 12Vibration Conductor

[0043] 13 Second suction nozzle

[0044] 14 Single-stage board

[0045] 15 Glue

[0046] 16 unipolar plates. DETAILED DESCRIPTION

[0047] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that those skilled in the art can more clearly understand how to practice the present invention. Although the present invention is described in conjunction with its preferred specific embodiments, these embodiments are only illustrative, rather than limiting the scope of the present invention.

[0048] A clamping tool for adhesive connection of metal bipolar plates of fuel cells comprises a positioning device, a heating device and a vibration device.

[0049] The positioning device is used to fix the plate posture. Figure 1 and Figure 2 The positioning device mainly includes a tooling upper cover plate 1, a tooling lower base plate 2, a positioning pin 3, a first suction nozzle 4, an air pipe joint 5, and a vacuum pump.

[0050] See also Figure 3 The tooling upper cover plate 1 is formed by two first tooling plates stacked one above the other and connected by screws. A plurality of first heating pipe grooves with semicircular cross sections are correspondingly provided on the adjacent surfaces of the two first tooling plates. The bottom surface of the first tooling plate located below is provided with a first tooling convex rib 6 corresponding to the field dividing path on the metal double-stage plate and a plurality of positioning pin holes 7 located around the first tooling convex rib 6, wherein the first tooling convex rib 6 is designed according to the field dividing path on the metal double-stage plate to be glued.

[0051] See also Figure 5The tooling bottom plate 2 is formed by two second tooling plates stacked one above the other and connected by screws. A plurality of second heating pipe grooves 8 with semicircular cross sections are correspondingly provided on the adjacent surfaces of the two second tooling plates. In this embodiment, the arrangement of the second heating pipe grooves 8 on the second tooling plates can be referred to Figure 4 The top surface of the second tooling plate located above is provided with a second tooling rib 9 corresponding to the field path on the metal double-stage plate and a plurality of positioning pins 3 located around the second tooling rib 9. The second tooling rib 9 is designed according to the field path on the metal double-stage plate to be glued. The arrangement of the positioning pins 3 can be seen in Figure 6 The two second tooling plates are provided with a plurality of vacuum channels, the upper ends of the vacuum channels are connected to the second tooling rib 9 and are connected to the first suction nozzle 4, and the lower ends of the vacuum channels are connected to the side of the second tooling plate located below and are connected to the air pipe joint 5.

[0052] The vacuum pump is connected to the air pipe joint 5 at the lower end of the plurality of vacuum channels through an air pipe. The vacuum pump may be a part of the positioning device or an independent device connected externally. The vacuum pump is not shown in the figure.

[0053] Heating devices are used to accelerate the curing of glue. Figure 2 , Figure 3 and Figure 5 The heating device mainly includes a heating tube 10, which is installed in a first heating tube groove of the tooling upper cover plate 1 and a second heating tube groove 8 of the tooling lower base plate 2.

[0054] The vibration device is used to vibrate out the air inside the glue to avoid bubbles during the curing process. Figures 1 to 3 , the vibration device mainly includes a vibration source 11, a vibration conductor 12, and a second suction nozzle 13. The vibration source 11 can be a part of the vibration device, installed on the top surface of the first tooling plate located above the tooling upper cover plate 1, or it can be an external independent device. A plurality of vibration conductors 12 are arranged on the two first tooling plates of the tooling upper cover plate 1, the upper end of the vibration conductor 12 is connected to the vibration source 11, and the lower end of the vibration conductor 12 extends to the first tooling rib 6, and is connected to the second suction nozzle 13. Among them, the vibration source 11 and the vibration conductor 12 are selected from the existing technology according to actual needs, as long as they can drive the second suction nozzle 13 to vibrate. In addition, it should be noted that, Figure 1 The end of each black line connected to the vibration source 11 is the position of the vibration conductor 12 in this embodiment. The black line only represents the schematic connection between the vibration source 11 and the vibration conductor 12, and is not a specific component.

[0055] Before using the clamping tool to glue and connect the metal bipolar plates, the first tooling rib 6 of the first tooling plate and the second tooling rib 9 of the second tooling plate need to be processed according to the field path distribution of the metal bipolar plates to be glued and connected.

[0056] After processing, see Figure 2 The method for bonding metal bipolar plates comprises the following steps:

[0057] (1) The robot arm places a monopolar plate 14 on the top surface of the bottom plate 2 of the tooling, so that the outer periphery of the monopolar plate 14 is limited by the positioning pins 3. Then the vacuum pump is started and the monopolar plate 14 is adsorbed by the first suction nozzle 4 to complete the posture fixation.

[0058] (2) The automatic glue coating machine applies glue 15 to the bonding area of ​​the monopolar plate 14 on the bottom plate 2 of the tooling.

[0059] (3) The robot arm places another monopolar plate 16 on the monopolar plate 14 on the lower base plate 2 of the tooling, and the upper cover plate 1 of the tooling cooperates with the lower base plate 2 of the tooling to clamp the two monopolar plates.

[0060] (4) The heating rods on the upper cover plate 1 and the lower base plate 2 of the tooling are powered on to heat the glue so that it solidifies quickly. At the same time, the vibration source 11 is started, and the second suction nozzle 13 is driven to vibrate out the air in the glue through the vibration conductor 12. After vibrating for a certain period of time, the vibration source 11 is turned off.

[0061] (5) After the upper cover plate 1 and the lower base plate 2 of the tooling are kept under pressure for a certain period of time, the upper cover plate 1 of the tooling is released from the tooling clamp, the vacuum pump is turned off, and the adsorption of the second suction nozzle 13 is released. In this way, the adhesive connection process of the metal bipolar plate is completed, and the robot arm can remove the metal bipolar plate from the lower base plate 2 of the tooling.

[0062] It should be noted that the fully described invention may also have a variety of variations and modifications, and is not limited to the specific embodiments described above. The above embodiments are merely illustrative of the invention, not limiting thereof. In short, the scope of protection of the invention should include those variations or substitutions and modifications that are obvious to a person of ordinary skill in the art.

Claims

1. A clamping tool for gluing and connecting metal bipolar plates of fuel cells, characterized in that: It includes a positioning device, a heating device, and a vibration device; The positioning device includes a tooling upper cover plate, a tooling lower base plate, a positioning pin, and a first suction nozzle, and the vibration device includes a vibration source, a vibration conductor, and a second suction nozzle; The tooling upper cover plate and the tooling lower base plate are both equipped with built-in heating devices; The bottom surface of the tooling upper cover plate is provided with a first tooling convex rib corresponding to the field path on the metal double-stage plate and a plurality of positioning pin holes located around the first tooling convex rib, and a plurality of vibration conductors are penetrated on the tooling upper cover plate, the upper end of the vibration conductor is connected to the vibration source, and the lower end extends to the first tooling convex rib and is connected to the second suction nozzle; A second tooling convex rib corresponding to the field path on the metal double-stage plate and a plurality of positioning pins located around the second tooling convex rib are provided on the top surface of the tooling lower bottom plate, and a plurality of vacuum channels are provided on the tooling lower bottom plate, the upper ends of the vacuum channels are connected to the second tooling convex rib and are connected to the first suction nozzle, and the lower ends of the vacuum channels are connected to the side of the tooling lower bottom plate; The heating device includes a heating tube, and a heating tube groove corresponding to the heating tube is provided in the tooling upper cover plate and the tooling lower bottom plate; The tooling upper cover plate is formed by connecting two first tooling plates stacked up and down, and the adjacent surfaces of the two first tooling plates are correspondingly provided with a plurality of first heating pipe grooves with semicircular cross-sections. The tooling lower bottom plate is formed by connecting two second tooling plates stacked up and down, and the adjacent surfaces of the two second tooling plates are correspondingly provided with a plurality of second heating pipe grooves with semicircular cross-sections.

2. The clamping tool for gluing and connecting metal bipolar plates of fuel cells according to claim 1 is characterized in that: The lower end of the vacuum channel on the lower bottom plate of the tooling leads to the side surface of the second tooling plate located below.

3. The clamping tool for gluing and connecting metal bipolar plates of fuel cells according to claim 1 is characterized in that: The vibration source is installed on the top surface of the tooling upper cover plate.

4. The clamping tool for gluing and connecting metal bipolar plates of fuel cells according to any one of claims 1 to 3, characterized in that: The positioning device also includes a vacuum pump, which is connected to the lower ends of multiple vacuum channels on the lower bottom plate of the tooling through an air pipe.

5. The clamping tool for gluing and connecting metal bipolar plates of fuel cells according to claim 4 is characterized in that: The positioning device also includes an air pipe joint, which is installed at the lower end of the vacuum channel on the lower bottom plate of the tooling.

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