Internal positioning tool structure of fuel cell

Abstract

The invention discloses an internal positioning tool structure of a fuel cell, which comprises a tool bottom plate provided with an opening and fixed with a rear end plate of the fuel cell through a bolt; the positioning pins are vertically arranged on the tool bottom plate, and every two positioning pins are symmetrically arranged; the positioning pin comprises two positioning rods, two combination plates and a bayonet lock; the diagonal planes of the two composition plates are spliced in an axial symmetry mode, the clamping pin is clamped at the joint of the two composition plates, one ends of the two composition plates are fixed, and the other ends of the two composition plates are fixedly arranged in the limiting groove in the tool bottom plate. The two positioning rods are arranged on the two sides of the two combination plates respectively, limiting is conducted through the positioning holes in the tool bottom plate, and the positioning rods make contact with the inner wall of a medium public channel of the fuel cell to position the fuel cell. The two groups of positioning pins form a spatial triangular structure, so that the rigidity and the stability of the internal positioning tool are remarkably improved, and the precision of the fuel cell electric stacking piece is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of fuel cells, and in particular to an internal positioning tooling structure of a fuel cell. Background Art

[0002] As an efficient and clean energy conversion device, fuel cells have broad application prospects in the energy field. The fuel cell stack is the core component of the fuel cell system, and its performance and reliability directly determine the quality of the entire fuel cell system. The stacking accuracy of the stack plays a vital role in the performance and reliability of the stack. High-precision stacking can ensure that the contact between each single cell is close and uniform, making the resistance distribution inside the stack more reasonable, thereby ensuring that the stack outputs stable voltage and current; it can reduce gas leakage and uneven current distribution, improve the energy conversion efficiency of fuel cells, and reduce energy loss; it can avoid local stress concentration and reduce damage to battery components, thereby extending the service life of the stack; it can ensure the stability of the internal structure of the stack and reduce the probability of failures such as gas channel blockage and electrode and electrolyte misalignment.

[0003] In order to ensure the stacking accuracy of fuel cell stacks, internal positioning and external positioning assembly tools are usually used. However, these existing assembly tools have the following problems and shortcomings in practical applications: limited by the requirements of high power density and high bipolar plate area utilization of fuel cells, the internal positioning tool is usually a simple slender rod. Due to its insufficient rigidity and large degree of freedom, the positioning accuracy of the internal positioning assembly tool is limited. In addition, since the internal positioning rod is nested inside the bipolar plate and membrane electrode, the accumulated position error of hundreds of stacked pieces causes the internal positioning tool to form shear force along the length direction, making installation and disassembly difficult, and easily causing damage to the internal components of the stack. The external positioning assembly tool needs to be close to the edge of the bipolar plate and membrane electrode, and coincide with the position of the stack tension bolts, which limits the overall structural design of the stack, or results in no position to set the external positioning tool, resulting in insufficient restrictions on the stacking freedom and reduced stacking accuracy. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the existing fuel cell internal positioning tooling, which has insufficient rigidity and stability, and the external positioning tooling interfering with the fuel cell stack tensioning bolts, thereby resulting in limited stack design or poor positioning effect.

[0005] In order to achieve the above object, the present invention provides an internal positioning tooling structure of a fuel cell, wherein the internal positioning tooling structure at least comprises:

[0006] A tooling bottom plate, the tooling bottom plate having an opening and being fixed to the lower end plate of the fuel cell by bolts;

[0007] Locating pins, the locating pins are vertically arranged on the tooling bottom plate, and the locating pins are symmetrically arranged in pairs;

[0008] The positioning pin comprises two positioning rods, two combination plates and a bayonet;

[0009] The chamfered surfaces of the two combined plates are axially symmetrically spliced, the bayonet is clamped at the connection of the two combined plates to fix one end of the two combined plates, and the other end of the two combined plates is fixed in the limiting groove on the tooling bottom plate; the two positioning rods are respectively arranged on both sides of the two combined plates, and are limited by the positioning holes on the tooling bottom plate, and the positioning rods are in contact with the inner wall of the medium common channel of the fuel cell to form a positioning for the fuel cell.

[0010] Preferably, the inner positioning tooling structure includes four positioning pins.

[0011] Preferably, the four positioning pins respectively form two sets of triangular stable structures in the medium common channel of the fuel cell, thereby improving the stability of the internal positioning tooling structure of the fuel cell.

[0012] Preferably, the positioning rod is a cylindrical slender rod.

[0013] Preferably, the positioning rod is made of glass fiber reinforced material.

[0014] Preferably, the positioning rod is made of glass fiber reinforced epoxy resin or polyphenylene sulfide.

[0015] Preferably, one end of the combined plate has a mortise and tenon structure matching the bayonet, so as to facilitate fixing the two combined plates with the bayonet.

[0016] Preferably, one side of each combined plate is a semicircular groove, and the cylindrical slender rod fits with the semicircular groove; the other side of each combined plate is a section with an angle with the thickness direction of the combined plate, so that the oblique sections of the two combined plates are axially symmetrically spliced.

[0017] Preferably, one end of the bayonet has a mortise and tenon structure matching the combined plate, so as to facilitate fixing the two combined plates to the bayonet.

[0018] Preferably, the bayonet has a bayonet opening for providing a force point when inserting and removing the bayonet.

[0019] Compared with the prior art, the beneficial effects of the present invention include at least:

[0020] (1) Four positioning pins are arranged in pairs in the medium common channel of the fuel cell. The two positioning pins located on the same side of the medium common channel of the fuel cell form an angle with each other. The four positioning pins form two sets of triangular stable structures in the medium common channel of the fuel cell. On the one hand, the diagonal angles of the medium common channel of the fuel cell are used to form a strong positioning constraint. On the other hand, the triangular stable structure formed between the angles effectively improves the rigidity and stability of the internal positioning tooling structure, thereby improving the stacking accuracy of the fuel cell battery.

[0021] (2) The positioning pin of the present invention comprises a positioning rod, two combination plates, and a locking pin. When disassembling, the locking pin is pulled out, and the two combination plates symmetrically spliced ​​with the beveled surfaces are rotated, so that the two combination plates can be separated from the positioning rod, so that a gap appears in the positioning pin that originally had no gap, so that the positioning rod can be easily removed from the medium common channel of the fuel cell without damaging the membrane electrode and the edges of the bipolar plate of the fuel cell; the positioning pin adopts a detachable design, which avoids the shear force on the internal positioning tooling caused by the accumulated position errors of hundreds of bipolar plates and membrane electrode stacks, thereby facilitating the installation and removal of the internal positioning tooling.

[0022] (3) The present invention can ensure the parallelism of the fuel cell stack without the need to set up a complex external positioning tooling structure, avoiding the problem of overlapping design positions of the external positioning tooling structure and the fuel cell stack tensioning bolts, and has no restrictions on the external structural design of the fuel cell stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the combination of the internal positioning tooling structure of the fuel cell of the present invention.

[0024] Figure 2 It is a schematic diagram of disassembly of the positioning pin of the present invention.

[0025] Figure 3 It is a top view of the positioning pin of the present invention.

[0026] Figure 4 It is a structural schematic diagram of the tooling base plate of the present invention.

[0027] Figure 5 It is a schematic diagram of a triangular stable structure formed on a tooling bottom plate by the inner positioning tooling structure of the present invention.

[0028] Figure 6 It is a schematic structural diagram of the positioning pin of the present invention.

[0029] Figure identification: 1-internal positioning tooling structure, 11-tooling bottom plate, 111-limiting groove, 112-positioning hole, 113-tooling bottom plate opening, 12-positioning pin, 121-positioning rod, 122-combination plate, 123-bayonet, 1231-bayonet opening, 2-fuel cell, 21-front end plate, 22-front insulating plate, 23-front current collecting plate, 24-bipolar plate and membrane electrode series core, 241-fuel cell medium common channel, 25-rear current collecting plate, 26-rear insulating plate, 27-rear end plate. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0031] like Figure 1 As shown, the present invention provides an internal positioning tooling structure 1 of a fuel cell, and the internal positioning tooling structure 1 at least comprises: a tooling bottom plate 11 and four positioning pins 12. As an example of one side of the tooling bottom plate 11, as shown in FIG. Figure 4 As shown, the tooling bottom plate 11 is provided with a total of four limit grooves 111, eight positioning holes 112 and four tooling bottom plate openings. The fuel cell 2 is located on the tooling bottom plate 11 as a whole and is positioned by four positioning pins 12. The fuel cell 2 comprises a front end plate 21, a front insulating plate 22, a front current collecting plate 23, a bipolar plate and a membrane electrode series core 24, a fuel cell medium common channel 241, a rear current collecting plate 25, a rear insulating plate 26, and a rear end plate 27. Bolts pass through the four tooling bottom plate openings on the tooling bottom plate 11 and are connected to the rear end plate 27 of the fuel cell 2, thereby fixing the fuel cell 2 on the tooling bottom plate.

[0032] The four positioning pins 12 are vertically arranged on the tooling base plate 11, and are symmetrically arranged in pairs. Figure 2 , Figure 3 As shown, each positioning pin 12 includes two positioning rods 121, two combination plates 122, and a locking pin 123. The positioning rods 121 are cylindrical slender rods made of glass fiber reinforced materials, such as glass fiber reinforced epoxy resin or polyphenylene sulfide. Each positioning rod 121 of each positioning pin 12 is respectively inserted into the positioning hole 112 on the tooling bottom plate 11, and the positioning rod 121 is limited by the positioning hole 112. The positioning rod 121 contacts the inner wall of the medium common channel 241 of the fuel cell to form a positioning for the fuel cell 2.

[0033] like Figure 3As shown, one side of the combined plate 122 is designed to be in the shape of a semicircular groove, the positioning rod 121 is fitted with the combined plate 122 of the semicircular groove, and the other side of the combined plate 122 is designed to be an oblique section having a certain angle with the thickness direction of the combined plate 122, and the oblique sections of the two combined plates 122 are axially symmetrically spliced ​​together to form a wider flat plate.

[0034] like Figure 6 As shown, the bayonet 123 is clamped at the joint of the two combined plates 122 of each positioning pin 12, so as to fix one end of the two combined plates 122, and the other end of the combined plate 122 is fixedly set in the limiting groove 111 on the tooling base plate 11, and the eight combined plates 122 of the four positioning pins 12 are respectively fixed in the four limiting grooves 111 on the tooling base plate 11. The ends of the bayonet 123 that contact the combined plates 122 have mortise and tenon structures that match each other, so as to facilitate the fixing of the two combined plates 122 and the bayonet 123. The bayonet 123 has a bayonet opening 1231, which is used to provide a force point when inserting and removing the bayonet 123.

[0035] like Figure 5 As shown, the four positioning pins 12 form angles with each other in the fuel cell medium common channel, thereby forming two sets of spatial triangular stable structures. The fuel cell medium common channel 241 forms a strong positioning constraint at the diagonal, and the formation of a spatial triangular stable structure can effectively improve the stability of the internal positioning fixture structure, and the parallelism of the fuel cell stack can be ensured without a complex external positioning fixture structure.

[0036] The disassembly and installation processes of the internal positioning tooling structure of a fuel cell of the present invention are inverse processes to each other, and are described in detail with the disassembly steps: Figure 2 As shown, when disassembling, first pull out the latch 123 from bottom to top along direction A, and then Figure 3 As shown, the combined plate 122 is rotated in the direction of B and then moved in the direction of C. At this time, the chamfered surfaces of the two combined plates 122 are separated from each other, and the two positioning rods 121 are separated. At this time, the gaps around the combined plate 122 are large, and it can be easily taken out from the fuel cell's medium common channel 241. At this time, the restraining force on the positioning rod 121 is reduced, and it no longer produces compression and friction with the inner wall of the fuel cell's medium common channel 241, so the positioning rod 121 can be easily pulled out. Since it is made of glass fiber reinforced material, it avoids the use of metal materials to rub against the bipolar plate during the lamination process to produce conductive debris, so it will not damage the membrane electrode and the edge of the bipolar plate. The steps for installation are opposite to those for disassembly.

[0037] In summary, the present invention provides an internal positioning tooling structure of a fuel cell, the internal positioning tooling structure at least comprises: a tooling base plate, the tooling base plate has an opening, and is fixed to the rear end plate of the fuel cell by bolts; positioning pins, the positioning pins are vertically arranged on the tooling base plate, and the positioning pins are symmetrically arranged in pairs; the positioning pins comprise two positioning rods, two combination plates, and a bayonet; the oblique sections of the two combination plates are axially symmetrically spliced, the bayonet is clamped at the connection of the two combination plates, one end of the two combination plates is fixed, and the other end of the two combination plates is fixed in the limiting groove on the tooling base plate; the two positioning rods are respectively arranged on both sides of the two combination plates, and are limited by the positioning holes on the tooling base plate, and the positioning rods are in contact with the inner wall of the medium common channel of the fuel cell to form the positioning of the fuel cell. The positioning pins of the internal positioning tooling structure of the present invention respectively form two groups of spatial triangular stable structures, which have strong rigidity and stability, thereby improving the stacking accuracy of the fuel cell stack; in addition, the internal positioning tooling structure of the fuel cell of the present invention adopts a detachable structure, which can easily realize the rapid disassembly and installation of the internal positioning tooling structure.

[0038] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A fuel cell internal positioning tooling structure, characterized in that: The inner positioning tooling structure at least comprises: A tooling bottom plate, the tooling bottom plate having an opening and being fixed to the rear end plate of the fuel cell by bolts; Locating pins, the locating pins are vertically arranged on the tooling bottom plate, and the locating pins are symmetrically arranged in pairs; The positioning pin comprises two positioning rods, two combination plates and a bayonet; The chamfered surfaces of the two combined plates are axially symmetrically spliced, the bayonet is clamped at the connection of the two combined plates to fix one end of the two combined plates, and the other end of the two combined plates is fixed in the limiting groove on the tooling bottom plate; the two positioning rods are respectively arranged on both sides of the two combined plates, and are limited by the positioning holes on the tooling bottom plate, and the positioning rods are in contact with the inner wall of the medium common channel of the fuel cell to form a positioning for the fuel cell.

2. The internal positioning fixture structure of the fuel cell according to claim 1, characterized in that: The inner positioning tooling structure includes four positioning pins.

3. The internal positioning fixture structure of the fuel cell according to claim 2, characterized in that: The four positioning pins respectively form two sets of triangular stable structures in the medium common channel of the fuel cell, thereby improving the stability of the internal positioning tooling structure of the fuel cell.

4. The internal positioning fixture structure of the fuel cell according to claim 1, characterized in that: The positioning rod is a cylindrical slender rod.

5. The internal positioning fixture structure of the fuel cell according to claim 1, characterized in that: The positioning rod is made of glass fiber reinforced material.

6. The internal positioning fixture structure of the fuel cell according to claim 5, characterized in that: The material of the positioning rod is glass fiber reinforced epoxy resin or polyphenylene sulfide.

7. The internal positioning fixture structure of the fuel cell according to claim 1, characterized in that: One end of the combined plate has a mortise and tenon structure matching the bayonet, so as to facilitate fixing the two combined plates with the bayonet.

8. The internal positioning fixture structure of the fuel cell according to claim 4, characterized in that: One side of each combined board is a semicircular groove, and the cylindrical slender rod fits with the semicircular groove; the other side of each combined board is a section with an angle with the thickness direction of the combined board, so that the oblique sections of the two combined boards are axially symmetrically spliced.

9. The internal positioning fixture structure of the fuel cell according to claim 1, characterized in that: One end of the bayonet has a mortise and tenon structure matching the combined plate, so as to facilitate fixing the two combined plates to the bayonet.

10. The internal positioning tooling structure of the fuel cell according to claim 1, characterized in that: The bayonet is provided with a bayonet opening for providing a force point when inserting and removing the bayonet.

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