JPH09283171A - Fastening device for fuel cell stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the weight of a device, and lower the cost by previously applying an opposite curved displacement to a bolster for fastening. SOLUTION: A bolster 3 is formed of a low-rigidity plate material, and it can be temporarily curved for displacement so as to be projected to a stack 1 showed with a two-dot chain line. Namely, a fixing bar 7 is fixed to both ends of the bolster 3, and fastened by a bolt-like tensile bar 6 and a nut 8 so as to be curved. A rod 4 is fixed near both ends of the bolster 3, and drawn from the two-dot chain line 3a condition to the direction of an arrow 10, and a flat surface bolster 3 showed with a solid line can be obtained. Consequently, since the bolster 3 as a fastening plate is formed of a low-rigidity plate material, weight is reduced and cost is lowered, After the fastening, since the bolster 3 is returned to the original flat shape for the surface contact with the stack 1, load is evenly applied to the surface.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fastening device for a fuel cell stack.

[0002]

2. Description of the Related Art As a conventional fastening device for a fuel cell stack, for example, a structure shown in FIG. 3 is known. In FIG. 3, 11 is a fuel cell stack and 12
Is an upper tightening plate, 13 is a lower tightening plate, 14 is a bellows, and 15 is a tightening bolt.

Here, since this type of tightening structure requires a uniform load distribution, a large number of bellows 14 and springs (not shown) are arranged in the plane.

[0004]

Since the bellows 14 and the springs described above are expensive, rigid clamping plates 12 and 13 are required when tightening without using them. However, this also has a problem that the cost is high and the weight is very large. The present invention is intended to solve such a problem. That is, it is an object of the present invention to provide a fuel cell stack fastening device that is low in cost and light in weight.

[0005]

In order to achieve the above object, the present invention has a header holding a fuel cell stack and a bolster made of a low-rigidity plate body. A rod disposed therebetween to elastically draw the bolster toward the header, and further, the bolster is temporarily bent in the convex direction toward the stack before the bolster is deformed. The flat surface was in pressure contact with the surface of the stack while still having prestress where it was pulled toward the stack by the rod to a flat surface.

According to the present invention, the fuel cell stack is sandwiched by a header and a bolster made of a low-rigidity plate, and the bolster is provided between the header and the bolster. A rod that is elastically attracted towards the stack, and yet the bolster has previously been temporarily convexly curved towards the stack and then pulled toward the stack by the rod and flattened. Since the flat surface of the stack is in pressure contact with the surface of the stack while having a prestress when it becomes a flat surface, the bolster is made of a plate body with low rigidity,
Light weight and low cost, and pre-stressed by applying reverse bending displacement to the bolster in advance,
Since this is a surface contact with the stack due to the tightening of the bolster and the bolster returning to its original flat shape, a uniform load is applied within the surface.

[0007]

FIG. 1 is a side view showing a first embodiment of the present invention. In FIG. 1, 1 is a fuel cell stack, 2 is a header, 3 is a bolster which will be described later, 4 is a rod, 5 is a hydraulic pulling device, 6 is a pull rod (tension bar), 7 is a fixed rod, and 8 is tension adjustment. It is a nut.

That is, the fuel cell stack 1 is sandwiched by a header 2 and a bolster 3 made of a low-rigidity plate. The bolster 3 is provided between the header 2 and the bolster 3. It has rods 4 and 4 which are elastically drawn towards the header 2 and said bolster 3
Has been pre-stressed when it has been temporarily curved in a convex shape toward the stack 1 in advance and then pulled toward the stack 1 by the rods 4 and 4 to become a flat surface. The flat surface is in pressure contact with the surface of the stack.

In the embodiment shown in FIG. 1, the bolster 3 can be temporarily curved and deformed so as to be convex toward the stack 1, as indicated by a chain double-dashed line 3a. That is, fixed rods 7, 7 are fixed near both ends of the bolster 3, and a pull rod 6 such as a bolt is bridged between the fixed rods 7, 7 by tightening the tension adjusting nut 8. The pull rod 6 can be pulled as shown by arrows 9 and 9 to bend the bolster 3 as shown by the chain double-dashed line 3a.

Further, in the embodiment shown in FIG. 1, the drawing devices 5 and 5 are hydraulic devices composed of cylinders and pistons, and the rods 4 and 4 are piston rods thereof, which are fixed near both ends of the bolster 3 and have two points. By pulling from the state of the chain line 3a by the rods 4 and 4 as shown by arrows 10 and 10, the bolster 3 having a flat surface like the solid line can be obtained.

In the fastening device for a fuel cell stack constructed as shown in FIG. 1, since the bolster 3 which is a fastening plate is made of a low-rigidity plate body, it is light in weight and low in cost, and the bolster 3 is attached to the bolster 3. Since a pre-stress is applied by applying a curving displacement in the opposite direction, and the bolster 3 returns to its original flat shape by tightening this, a uniform load is applied to the inside of the stack 1. It will be like this. Moreover, since the bellows 14 and a large number of springs in place of the bellows 14 unlike the conventional ones are not used, the cost is further reduced.

In FIG. 1, a pull rod (tension bar) 6 or the like is used to apply the reverse bending deformation to the bolster 3 in advance, but the plate body having low rigidity is rolled and deformed to maintain the prestress. You may incorporate the one as it is.
Further, although the hydraulic device is used as the pulling device 5 for returning the bolster 3 to the original flat shape, a simple and inexpensive spring may be used for this.

FIG. 2 is a side view showing a second embodiment of the present invention. In FIG. 2, the header 2 of the tightening device of FIG. 1 is used as an intermediate header, and the fuel cell stack 1,
Incorporating 1 into each bolster 3, 3
Is temporarily curved in a convex shape toward the corresponding stack 1, 1 in advance, and is then drawn toward the corresponding stack 1, 1 by the rods 4, 4 to obtain a flat surface. The flat surfaces of the stacks 1 and 1 are in pressure contact with the surfaces of the stacks 1 and 1, respectively.

[0014]

As described above, according to the present invention,
A rod having a header holding the fuel cell stack and a bolster made of a low-rigidity plate body, and provided between the header and the bolster to elastically pull the bolster toward the header. In addition, the bolster is temporarily curved in a convex shape toward the stack in advance and then prestressed when the bolster is pulled toward the stack by the rod and becomes a flat surface. Since the flat surface of the stack is in pressure contact with the surface of the stack as it is, the bolster that is the tightening plate is made of a plate body with low rigidity, which results in light weight and low cost. Since a pre-stress is applied by applying a reverse bending displacement and tightening this, the bolster is in surface contact with the stack due to returning to the original flat shape, Uniform load so according within. Moreover, since a bellows and a large number of springs in place of the bellows, which have been used conventionally, are not used, the cost can be further reduced.

[Brief description of drawings]

FIG. 1 is a side view showing a first embodiment of the present invention.

FIG. 2 is a side view showing a second embodiment of the present invention.

FIG. 3 is a side view showing an example of a conventional technique.

[Explanation of symbols]

 1 Fuel Cell Stack 2 Header 3 Bolster 4 Rod 5 Pulling Device 6 Pull Rod

Claims (1)

[Claims] 1. A header having a fuel cell stack and a bolster made of a low-rigidity plate body, and provided between the header and the bolster, the bolster is elastic toward the header. The bolster is temporarily curved in a convex shape toward the stack in advance, and then the rod is drawn toward the stack by the rod to form a flat surface. A fastening device for a fuel cell stack, characterized in that the flat surface thereof is in pressure contact with the surface of the stack while still having a prestress.