JP2006123590A - Fuel tank mounting structure - Google Patents

Abstract

To reliably prevent the movement of the hydrogen tank in the axial direction while reducing the tightening force of the band. A ring shape in which a substantially cylindrical hydrogen tank 10 for storing hydrogen gas under pressure is wound around the outer periphery thereof. In the fuel tank mounting structure fixed to the vehicle body by the bands 20A and 20B, the ribs 15a and 15b that are paired apart from each other in the axial direction are provided on the outer periphery of the hydrogen tank 10 in the circumferential direction. , 15b, a band 20A is sandwiched between them.
[Selection] Figure 3

Description

  The present invention relates to a structure for mounting a fuel tank to a vehicle body.

Some automobiles use natural gas vehicles that run on gas fuel as an output from an internal combustion engine, and generate electricity by supplying hydrogen as fuel gas and oxygen as oxidant gas. A fuel cell vehicle that travels by driving a motor is known.
Some gas fuel vehicles of this type have a fuel tank filled with compressed natural gas or hydrogen gas mounted on the rear of the vehicle body. As a mounting structure for this fuel tank, a ring-shaped metal Some are attached to the vehicle body via a band by winding a band (fixing member) and fixing the band to the vehicle body. (For example, refer to Patent Document 1).
Further, in addition to the fixing by the band, there is also a structure in which a restricting member that is locked to the dome portion at the axial end portion of the fuel tank is provided on the vehicle body to reliably restrict the movement of the fuel tank in the axial direction. (For example, refer to Patent Document 2).
JP-A-9-290650 JP 2002-120573 A

By the way, when the fuel tank is fixed with a band, there is a demand for reducing the tightening force by the band in order to improve the durability of the fuel tank. However, if the band tightening force is reduced, there is a concern that the fuel tank may easily move in the axial direction.
In order to cope with this, if a restricting member for restricting movement of the fuel tank in the axial direction is provided in the vehicle body separately from the band as in Patent Document 2, not only the number of parts increases but also the restricting member Various problems occur, such as requiring a space for mounting.
Therefore, the present invention provides a fuel tank mounting structure that can reliably prevent movement of the fuel tank in the axial direction while reducing the fastening force of the fixing member with a simple structure.

In order to solve the above-mentioned problems, the invention according to claim 1 is a ring-shaped structure in which a substantially cylindrical fuel tank (for example, a hydrogen tank 10 in an embodiment to be described later) for storing fuel under pressure is wound around its outer periphery. In a fuel tank mounting structure fixed to a vehicle body (for example, a sub-frame 122 in an embodiment to be described later) by a fixing member (for example, a band 20A in an embodiment to be described later), it is separated from each other in the axial direction on the outer periphery of the fuel tank. A pair of projecting bodies (for example, projecting ribs 15a and 15b in the embodiments described later) are provided in the circumferential direction, and the fixing member is sandwiched in an axial gap between the projecting bodies. .
With this configuration, the fixing member is sandwiched in the gap between the protrusions, so even if the fastening force of the fixing member wound around the fuel tank is reduced, the relative movement in the axial direction between the fixing member and the fuel tank is prevented. It can be reliably prevented. Further, the fuel tank can be easily positioned. Since only the protrusions are provided on the outer periphery of the fuel tank, the structure is simple and relatively little space is required.

The invention according to claim 2 is characterized in that, in the invention according to claim 1, the protruding body is formed so as to make one round of the outer periphery of the fuel tank continuously.
With this configuration, the axial force transmission between the fixing member and the protrusion is performed over substantially the entire circumference, so that the local stress concentration in the fuel tank is locally concentrated. Can be prevented.
The invention according to claim 3 is characterized in that, in the invention according to claim 1 or 2, the protrusion is formed integrally with a fuel tank.
By configuring in this way, an increase in the number of parts can be prevented.

According to the first aspect of the present invention, even if the fastening force of the fixing member wound around the fuel tank is reduced, relative movement in the axial direction between the fixing member and the fuel tank can be reliably prevented. Further, the fuel tank can be easily positioned. Furthermore, the structure is simple and relatively little space is required.
According to the invention which concerns on Claim 2, the stress concentration of the local axial direction to a fuel tank can be prevented.
According to the invention which concerns on Claim 3, the increase in a number of parts can be prevented.

  An embodiment of a fuel tank mounting structure according to the present invention will be described below with reference to the drawings of FIGS. In addition, the Example demonstrated below is the aspect of the attachment structure of the fuel tank in a fuel fuel cell vehicle.

As shown in FIG. 1, in this fuel-fuel cell vehicle, a rear floor 102 that is stepped and formed so as to rise rearward is joined to the rear edge of a front floor 101 that forms a vehicle body floor. A cross member 104 that forms a vehicle body skeleton is joined to the back side of the stepped portion 103 of the rear floor 102. On the lower surface of the front floor 101, floor frames 105 and 106 that form vehicle body skeleton portions are joined to the left and right along the vehicle length direction toward the outside.
Inside sills 107 and 108 are joined to the left and right edges of the front floor 101, and inside sill extensions 109 and 110 are provided at the rear ends of the inside sills 107 and 108. The inside sills 107 and 108 are members that are joined to an outside sill (not shown) to form a vehicle body skeleton.

Front brackets 111 and 111 are joined to the inner side surfaces of the inside sill extension tensions 109 and 110, respectively (for convenience of illustration, the front bracket 111 on the inside sill extension tension 110 side is omitted in FIG. 1 and FIG. 2). .
Each front bracket 111 is joined to the lower surface of the rear floor 102 and the rear frames 113 and 114, which are members forming the vehicle body frame portion, and the lower surface of the cross member 104 and the floor frames 105 and 106, whereby the rear frame 113, The front end portion of 114 is connected to the inside sills 107 and 108 and the floor frames 105 and 106 via the front brackets 111 and 111.

Rear brackets 117 and 118 are attached to the lower surfaces of the rear end portions of the rear frames 113 and 114, respectively.
Here, two cross members 104A and 104B are joined between the left and right rear frames 113 and 114, and a bumper beam 121 is attached to each rear end, specifically, the rear brackets 117 and 118, respectively.
A subframe 122 is fixed from below to each color nut 115 provided on the front brackets 111 and 111 and the rear brackets 117 and 118 by bolts 123 (for the sake of illustration, the inside sill tension tension 110 is shown in FIG. The color nut 115 of the front bracket 111 on the side is omitted).

  The sub-frame 122 is a member formed in a rectangular frame shape by left and right frame members 124 and 125 and front and rear frame members 126 and 127, and includes a cross beam 128 in the vehicle width direction. Two cylindrical hydrogen tanks 10A and 10B as fuel tanks (hereinafter referred to as hydrogen tanks 10 unless otherwise distinguished) are arranged with their axes aligned in the vehicle width direction, and are used as fixing members. The bands 20A and 20B (hereinafter, referred to as the band 20 when there is no need to distinguish between them) are fastened and fixed. The mounting structure of the fuel tank 10 will be described in detail later. A suspension unit 133 is attached to the subframe 122.

The corners between the front ends of the left and right frame members 124 and 125 and both ends of the front frame member 126 and the corners between the rear ends of the left and right frame members 124 and 125 and both ends of the rear frame member 127 Is provided with an insertion portion 134 for a bolt 123 to be inserted into the collar nut 115.
Bolts 123 are inserted into the respective insertion portions 134 of the sub-frame 122 configured as described above, and the bolts 123 are inserted into collar nuts 115 attached to the left and right front brackets 111 and rear brackets 117 and 118 and tightened. By fixing, the sub-frame 122 is fixed to the rear frames 113 and 114.

Next, the mounting structure of the hydrogen tank 10 will be described with reference to FIGS.
The hydrogen tank 10 includes a reinforcing layer 19 made of CFRP (carbon fiber reinforced resin) on the outside of an aluminum alloy liner (not shown). As shown in FIG. 3, the hydrogen tank 10 is configured by connecting dome portions 12A and 12B having a substantially hemispherical shape to both ends of a cylindrical straight body portion 11, and at the top of one dome portion 12A. A solenoid valve unit 14 is attached to the gas inlet / outlet portion 13 provided.

  The straight body portion 11 of the hydrogen tank 10 has a pair of projecting ribs (projection bodies) 15a and 15b which are arranged in parallel and spaced apart from each other in the axial direction of the hydrogen tank 10 at a portion close to the dome portion 12A. It is formed in a ring shape over the entire circumference. In addition, the ribs 16a and 16b that are paired by being spaced apart from each other in the axial direction of the hydrogen tank 10 and forming a pair also in the portion near the dome portion 12B in the straight body portion 11 are provided in the circumferential direction. It is formed in a ring shape over the circumference. That is, the protrusion ribs 15a, 15b, 16a, 16b are formed so as to make one round of the outer periphery of the hydrogen tank 10 continuously.

  The width dimension (the length along the axial direction of the hydrogen tank 10) of the groove 17 formed between the projecting ribs 15a and 15b is constant over the entire circumference, and is set so that the band 20A can be accommodated without a gap. . The width dimension of the groove 18 formed between the ribs 16a and 16b (the length along the axial direction of the hydrogen tank 10) is also constant over the entire circumference, but the width dimension of the groove 18 is the width dimension of the band 20B. The band 20B is set in the groove 18 with a gap. These projecting ribs 15a, 15b, 16a, 16b are formed by making the reinforcing layer 19 thicker than other parts, and therefore the projecting ribs 15a, 15b, 16a, 16b are It is formed integrally with the fuel tank 10.

  The band 20 is made of metal and is formed into an annular shape by connecting a first band 21 and a second band 22 that are divided into two in the circumferential direction, and the longitudinal direction of the first band 21 and the second band 22 The connecting stays 23 are provided at the respective end portions. In addition, fixing stays 24 and 25 for fixing to the subframe 122 are provided at predetermined portions in the longitudinal direction of the first band 21 and the second band 22 respectively.

  The first band 21 and the second band 22 of the band 20 </ b> A are inserted into the grooves 17 between the protruding ribs 15 a and 15 b of the hydrogen tank 10, and are arranged so as to form an annular shape along the outer periphery of the straight body portion 11. Then, the connecting stay 23 of the first band 21 and the connecting stay 23 of the second band 22 facing each other are connected by a bolt and nut. Here, the band 20A is formed in an annular shape by connecting two places in the circumferential direction with bolts, and at least one of them is connected to the connecting stay 23 and the second stay of the first band 21 as shown in FIG. A spring 27 and a washer 28 are attached to a bolt 26 through which the connecting stay 23 of the band 22 is inserted, and a nut 29 is screwed together. By configuring in this way, the band 20A can be expanded and contracted following the expansion and contraction of the hydrogen tank 10, so that even if the hydrogen tank 10 expands and contracts, the hydrogen tank can be operated with a substantially constant clamping force. 10 can be tightened. The tightening force can be set as appropriate depending on the spring constant of the spring 27 and the tightening degree of the nut 29. Since the band 20A is inserted into the groove 17 with almost no gap, the band 20A is sandwiched between the ribs 15a and 15b. In this state, both outer side surfaces of the band 20A substantially come into surface contact with the inner side surfaces of the opposed rib ribs 15a and 15b.

  The first band 21 and the second band 22 of the band 20 </ b> B are inserted into the groove 18 between the protruding ribs 16 a and 16 b of the hydrogen tank 10, and are arranged so as to form an annular shape along the outer periphery of the straight body portion 11. Since the connection stay 23 of the first band 21 and the connection stay 23 of the second band 22 are the same as those of the band 20A, the description thereof is omitted. The width dimension of the groove 18 is set to be larger than the width dimension of the band 20B by a predetermined dimension so that the band 20B is accommodated in the groove 18 with a gap so as to absorb an attachment error to the subframe 122. To be able to do that.

  The hydrogen tanks 10A, 10B are fixed by bolting the fixing stays 24, 25 of the first band 21 and the second band 22 of the bands 20A, 20B to the frame members 126, 127 or the cross beam 128 of the subframe 122. Is fixed to a sub-frame 122 forming a part of the vehicle body via the bands 20A and 20B. When the bands 20A and 20B are fixed to the subframe 122, the band 20A is fixed first, and then the band 20B is fixed. Thereby, it can position on the dome part 12A side of the hydrogen tank 10, and as a result, the vehicle width direction position with respect to the sub-frame 122 of the hydrogen tank 10 can be positioned accurately.

According to the tank mounting structure of this embodiment, the band 20A is sandwiched between the protruding ribs 15a and 15b formed integrally with the hydrogen tank 10 without any gap, so that the tightening force of the band 20A wound around the hydrogen tank 10 is increased. Even if it is reduced, the relative movement of the hydrogen tank 10 and the band 20A in the axial direction can be reliably prevented, and therefore the axial movement of the hydrogen tank 10 relative to the vehicle body can be reliably prevented. Thereby, the clamping force with respect to the hydrogen tank 10 of the band 20B can also be reduced. That is, the clamping force of the bands 20A and 20B can be reduced while preventing the hydrogen tank 10 from moving in the axial direction, and the durability of the hydrogen tank 10 can be improved.
Further, as described above, the positioning of the hydrogen tank 10 can be facilitated. Moreover, since the rib ribs 15a, 15b, 16a, and 16b are only provided on the outer periphery of the hydrogen tank 10, the structure is extremely simple, and the installation space is almost the same as the conventional one. In addition, since the ribs 15a, 15b, 16a, and 16b are formed integrally with the hydrogen tank 10, the number of parts does not increase.

  In addition, the ribs 15a and 15b are formed so as to continuously make one round of the outer periphery of the hydrogen tank 10, and both side surfaces of the band 20A come into surface contact with the inner side surfaces of the ribs 15a and 15b. Since the axial force is transmitted between the band 20A and the ribs 15a and 15b over substantially the entire circumference, the local stress concentration in the axial direction on the hydrogen tank 10 is prevented. It is very preferable and advantageous in terms of strength.

[Other Examples]
The present invention is not limited to the embodiment described above.
For example, in the above-described embodiment, the ribs 15a and 15b are provided in a complete ring shape (annular shape). However, arc-shaped ribs having a predetermined length in the circumferential direction are spaced apart in the circumferential direction. Alternatively, they may be arranged so as to be paired in the axial direction.
The fuel tank is not limited to a hydrogen tank, and may be an LP gas tank.

It is a disassembled perspective view in one Example of the fuel tank mounting structure which concerns on this invention. It is an assembly perspective view of the fuel tank mounting structure in the embodiment. It is a disassembled perspective view of a fuel tank and a band. It is an expansion perspective view which shows the connection part of a band.

Explanation of symbols

10, 10A, 10B Hydrogen tank (fuel tank)
15a, 15b ridge rib (ridge body)
20A band (fixing member)
122 Subframe (car body)

Claims (3)

In a fuel tank mounting structure in which a substantially cylindrical fuel tank that pressurizes and stores fuel is fixed to the vehicle body by a ring-shaped fixing member wound around the outer periphery thereof,
A fuel is characterized in that a pair of protruding ridges spaced apart from each other in the axial direction are provided on the outer periphery of the fuel tank in the circumferential direction, and the fixing member is sandwiched between gaps in the axial direction between the ridges. Tank mounting structure.   2. The fuel tank mounting structure according to claim 1, wherein the protruding body is formed so as to continuously go around the outer periphery of the fuel tank substantially once. 3.   The fuel tank mounting structure according to claim 1, wherein the protrusion is formed integrally with the fuel tank.

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