Tank mounting structure and vehicle

Abstract

Mounting structure for a tank (60), comprising: a frame (70) configured to mount the tank (60); a band (80) configured to fix the tank (60) in a state in which the band (80) sandwiches the tank (60) with the frame (70), and the band (80) deforms according to the expansion or contraction of the tank (60), wherein one end portion of the band (80) is fixed to the frame (70) via a hinge (82) and a first screw (83), and the other end portion of the band (80) is fixed to the frame (70) with a second screw (83), while applying a compressive force to the tank (60) using an elastic body (84); and a tank protector (90) configured to be attached to an outer side of the band (80).

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThe invention relates to a tank mounting structure and a vehicle.2. Description of the Prior ArtIn JP 2005-119 595 A, a construction is disclosed in which a protector covering a rear side of a tank body is provided in a rear axle of a vehicle to alleviate an impact on the tank storing the gas used for a fuel cell. A mounting structure for a tank having a frame and a band by means of which the tank is fastened to the frame is known from JP 2012-240 448 A. Further prior art is found in DE 10 2005 037 636 A1, DE 10 2015 116 450 A1, JP 2001-163 067 A, US 2012 / 0 213 580 A1 and EP 3 078 532 A1.SUMMARY OF THE INVENTIONNormally, a tank expands and contracts depending on the amount of the stored gas. Therefore, in the configuration described in JP 2005-119 595 A, when the tank contracts, a gap between the tank and the protector may increase. In addition, when a force is applied to the protector from the outside in a state in which a foreign object such as a large stone is caught in the expanded gap, a portion of the tank that is in contact with the caught foreign object is locally applied with a force. This can damage the tank. Based on the prior art, it is an object of the invention to offer a technology that prevents an increase in the gap between the tank and the protector or protection. This object is achieved with the mounting structure according to claim 1 and the vehicle according to claim 7; advantageous refinements are the subject matter of the dependent claims.It is possible to carry out the invention in the following aspects.According to the present invention, a tank mounting structure for a tank is proposed. The mounting structure for a tank includes a frame, a band, and a tank guard. The frame is configured to secure the tank. The band is configured to fix the tank in a state where the band encloses the tank with the frame, and the band deforms according to expansion or contraction of the tank, one end portion of the band is fixed to the frame via a hinge and a first bolt, and the other end portion of the band is fixed to the frame with a second bolt while applying a pressing force to the tank using an elastic body. The tank guard is configured to be attached to an exterior of the strap. In the mounting structure for a tank according to this aspect, since the tank protector and the band are connected to each other, the tank protector moves according to expansion or contraction of the tank. It is thus possible to limit the expansion of a gap between the tank and the tank protection.In the mounting structure for a tank, the tank protector according to the aspect includes a center member and end portion members. The center member is disposed on an outer side of a cylinder portion which is a cylindrical portion of the tank. The end portion elements are respectively disposed on the outer sides of dome portions. The dome portions are disposed on both end sides of the cylinder portion of the tank. The end portion elements may be thicker than the central element. In the mounting structure for a tank according to this aspect, the dome portions having relatively low strength are selectively protected by the end portion members. At the same time, by reducing the thickness of the center member to be thinner than the end portion members, it is possible to reduce a weight of the fuel tank.In the mounting structure for a tank according to this aspect, the shear strength of the tank protector may be larger than the shear strength of the band. In addition, the band may be made of metal. Moreover, the band may be made of an elastic resin material. Further, the lower ends of the end portion members of the fuel tank may be positioned to be lower than a lower end of the center member of the fuel tank.It is possible to carry out the invention in various aspects. For example, it is possible to implement the invention in one aspect such as a vehicle having the mounting structure for a tank.BRIEF DESCRIPTION OF THE DRAWINGSThe features and advantages, and technical and economic significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like reference numerals designate like elements, and wherein: FIG. 1 is a view of a vehicle having a tank mounting structure for a tank as an embodiment of the invention; FIG. 2 is a sectional view of a tank; FIG. 3 is a perspective view of the mounting structure for the tank for the vehicle; FIG. 4 is a sectional view of the mounting structure for the tank in a cylinder portion of the tank; and FIG. 5 is a sectional view of the mounting structure for the tank in a dome portion of the tank.DETAILED DESCRIPTION OF EMBODIMENTSA. EmbodimentsFIG. 1 is a view of a vehicle 100 having a mounting structure for a tank 60 as an embodiment of the invention. In the embodiment, a fuel cell vehicle is used as the vehicle 100. The description of the directions in the vehicle 100 ("right", "left", "front", "rear", "top", and "bottom") indicates the directions based on a driver who is in the vehicle 100. In FIG. 1, a forward direction of the X axis indicates a vehicle front direction, a forward direction of the Y axis indicates an upper side of the gravity direction, and a forward direction of the Z axis indicates a vehicle right direction. That is, the X-axis direction indicates a front-rear direction of the vehicle, the Y-axis direction indicates the gravity direction, and the Z-axis direction indicates a width direction of the vehicle. The axes X, Y and Z are identical in the drawings of Fig. 1.The vehicle 100 includes a fuel cell stack 10 and the tank 60. the fuel cell stack 10 is manufactured by, for example, stacking or stringing power modules each having a membrane electrode assembly (MEA) in which both electrodes, an anode and a cathode, are connected to both sides of an electrolyte film. Current is generated in the fuel cell stack 10 by an electrochemical reaction between hydrogen gas as fuel gas from the tank 60 and oxygen in the atmosphere. In the embodiment, the fuel cell stack 10 is disposed in a front part of the vehicle 100 (on a +X axis direction side). Specifically, the fuel cell stack 10 is disposed at a location where the fuel cell stack 10 partially overlaps front wheels FW in the front-rear direction (X-axis direction) of the vehicle 100.In the embodiment, the tank 60 is disposed in the rear part of the vehicle 100 (on an -X axis direction side) along the width direction of the vehicle 100 (the Z axis direction). Specifically, the tank 60 is disposed at a location where the tank 60 partially overlaps rear wheels RW in the front-rear direction (X-axis direction) of the vehicle 100, and the remaining part of the tank 60 is located behind the rear wheels RW.FIG. 2 is a sectional view of the tank 60. in the embodiment, the tank 60 includes a liner 62 and a reinforcing layer 64.The liner 62 of the tank 60 is an airtight container that stores a fluid. As the material for the liner 62, aluminum, stainless steel, and resin, for example, may be used. The liner 62 includes cap portions 61 on both end sides in the longitudinal direction. Each of the cap portions 61 functions as a pipe when gas is stored in the liner 62. In the embodiment, an outer diameter of the tank 60 changes by about 1 mm to about 2 mm depending on a filling amount of hydrogen gas inside the tank 60.The reinforcing layer 64 of the tank 60 is a layer formed by winding a resin-impregnated fiber bundle around a surface of the liner 62. The reinforcing layer 64 is provided to improve the strength of the tank 60. In the embodiment, carbon fibers are used as the fiber for the reinforcing layer 64.In the embodiment, the tank 60 includes a cylinder portion 11 having a cylindrical shape and formed in a central portion, and approximately hemispherical dome portions 12 provided on both end sides of the cylinder portion 11, respectively. Since the reinforcing layer 64 becomes thinner in a part of each dome portion 12, the cylinder portion 11 is normally liable to have a higher strength than the dome portions 12.FIGS. 3 to 5 are views of a mounting structure for the tank 60 for the vehicle 100. FIG. 3 is a perspective view of the mounting structure for the tank 60 for the vehicle 100. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3 and is a sectional view of the mounting structure in the cylinder portion 11 of the tank 60; FIG. 5 is a sectional view taken along line V-V in FIG. 3 and is a sectional view of the mounting structure in the dome portion 12 of the tank 60; the mounting structure for the tank 60 includes frames 70, straps 80, and a tank guard 90.The frames 70 are members used for fixing the tank 60 (see FIG. 3 ). In the embodiment, the frames 70 are disposed below (on a -Y axis direction side) the tank 60 and along the front-rear direction (the X axis direction) of the vehicle 100. In the embodiment, the two frames 70 are arranged in parallel to each other below the cylinder portion 11 of the tank 60.As illustrated in FIG. 4, in the embodiment, both ends of each frame 70 in the front-rear direction (X-axis direction) are fixed to a lower surface of an underbody 20 of the vehicle 100 with brackets 22 and bolts 21. In the embodiment, a central portion of the frame 70 is bent along the shape of the tank 60 and has a shape recessed downward.The straps 80 are members that fix the tank 60 in a state in which the straps 80 sandwich the tank 60 with the frame 70, and the straps 80 deform according to expansion or contraction of the tank 60 (see FIG. 3 ). In the embodiment, each of the belts 80 is provided on an upper side (a +Y axis direction side) of the cylinder portion 11 of the tank 60, and has a shape extending in the front-rear direction of the vehicle 100 (the X axis direction). In the embodiment, the two belts 80 are arranged parallel to each other. In the embodiment, the bands 80 are bent along a perimeter of the tank 60.As illustrated in FIG. 4, in the embodiment, each end portion of each band 80 on the rear side (the -X axis direction side) of the vehicle 100 is fixed to the frame 70 via a hinge 82 and a bolt 83. Further, an end portion of each band 80 on the front side (the +X axis direction side) of the vehicle 100 is fixed to the frame 70 by the bolt 83 while a pressing force is applied to the tank 60 with a spring 84. In the structure, the straps 80 fix the tank 60 in the state where the straps 80 sandwich the tank 60 with the frames 70, and the straps 80 deform according to expansion or contraction of the tank 60.The tank protector 90 is a member that protects the tank 60 from external influences. For example, an external force is applied when the vehicle 100 collides. The tank guard 90 is disposed on an outer side of the tank 60 and is also fixed to the outer sides of the straps 80. The tank guard 90 may be attached to the insides of the straps 80 or may be attached to the insides of the straps 80 and the outsides of the straps 80 in an alternative not claimed. In the latter case, two of the tank protection devices 90 are used.Regarding the protection of the tank 60, when the vehicle 100 is viewed from the rear side (the -X axis direction side) parallel to the X axis direction, it is preferable that a ratio of an area of the tank 60 overlapping the tank protection 90 is at least 50% of the entire tank 60. It is particularly preferred that the ratio is 60%, and the ratio of 70% is even more preferred. Meanwhile, in terms of weight reduction of the tank guard 90, it is preferable that the ratio of the area of the tank 60 overlapping the tank guard 90 is 90% or less of the entire tank 60, and the ratio of 80% or less is particularly preferable. In the embodiment, when the vehicle 100 is viewed from the rear side (the -X axis direction side) parallel to the X axis direction, the ratio of the area of the tank 60 overlapping the tank guard 90 is 70% or more but not more than 80% of the entire tank 60.As for the protection of the tank 60 from external influences, it is preferable that the shear strength of the tank guard 90 is larger than that of the tapes 80. The shear strength is proportional to the thickness of an element. In the embodiment, the tank guard 90 is made of metal that is the same material as that of the band 80. Since the tank protector 90 is thicker than the band 80, the shear strength of the tank protector 90 is larger than that of the band 80, the material of the tank protector 90 is not limited to metal, and may be made of other materials such as carbon fiber resin and polycarbonate.As shown in FIG. 4, in the embodiment, the tank guard 90 is fixed to each of the straps 80 at two locations by bolts 92, 93. A method of fixing the tank guard 90 is not limited to screws, but may be, for example, welding between the tank guard 90 and the bands 80. In the embodiment, the fuel tank guard 90 is fixed to portions of the straps 80 other than the end portions in the front-rear direction (X-axis direction). In the embodiment, the portion of the fuel tank 90 where the bolt 92 is provided is thinner than the rest of the fuel tank 90 from the viewpoint that the bolt 92 provided on the upper side does not come into contact with the underbody 20. For example, the portion of the fuel tank 90 in which the bolt 92 is provided may have the same thickness as the rest of the fuel tank 90.As illustrated in FIG. 3, the fuel tank guard 90 in the embodiment is made up of three members. Specifically, the fuel tank guard 90 includes a center member 95 disposed at the center and two end portion members 96 disposed on both end sides of the center member 95. The center member 95 is a member disposed on an outer side of the cylinder portion 11 of the tank 60. The end portion members 96 are members respectively disposed on the outer sides of the dome portions 12 of the tank 60. In the embodiment, the center member 95 and each of the end portion members 96 are joined together by welding. Further, an overlapping portion of the center member 95 and each of the end portion members 96 has a width required for welding (e.g., between about 1 cm and 2 cm), and the center member 95 does not extend to both ends of the tank guard 90. In this way, it is possible to limit a chattering elastic deformation of the end portion members 96 generated by vibration of the vehicle 100 in the front-rear direction (X-axis direction). The end portion members 96 and the center member 95 may be welded together by their end surfaces.In the embodiment, a thickness of each of the end portion members 96 is larger than that of the center member 95. "The thickness" denotes a distance between a pair of flat plates sandwiching a flat portion of a member. Thus, the dome portions 12 having relatively low strength are selectively protected by the end portion members 96. At the same time, by reducing the thickness of the center member 95 to be smaller than that of the end portion members 96, the weight of the fuel tank guard 90 is reduced. The invention is not limited thereto, and the center member 95 may have the same thickness as the end portion members 96, or the center member 95 may be thicker than the end portion members 96. the fuel tank 90 may be made of, for example, a single member instead of the three members.In the embodiment, the tank guard 90 is provided on the rear side (the -X axis direction side) of the tank 60. In this way, the tank guard 90 may protect the tank 60 from external forces from the rear of the vehicle 100. The invention is not limited thereto, and the tank guard 90 may be provided on the front side (the +X axis direction side) of the tank 60. Since the tank guard 90 is provided on the front side of a portion of the tank 60 to which the external force can be applied, the tank guard 90 can efficiently protect the tank 60.In the embodiment, when the fuel tank 90 is viewed in the width direction of the vehicle 100 (Z-axis direction), the fuel tank 90 is bent along the surface of the tank 60. This prevents the fuel tank guard 90 from being bent in the width direction (Z-axis direction).Further, as illustrated in FIG. 3, in the embodiment, an upper end (an end on the +Y axis direction side) of the center member 95 of the fuel tank 90 is at the same height as an upper end of each end portion member 96. as illustrated in FIG. 4, the upper end of the fuel tank 90 is located above a surface P 1 of the tank 60. the surface P 1 is located above a horizontal plane S 1 at an angle of 45° to a central axis CX. That is, even when the tank 60 is applied with an external force from the rear side (the -X axis direction side) to the front side (the +X axis direction side) of the vehicle 100 above the tank guard 90, the horizontal plane S 1 passes through the central axis CX of the tank 60, half of the external force is rejected along the surface of the tank 60.Further, as illustrated in FIG. 3, in the embodiment, a lower end of each of the end portion members 96 of the tank protector 90 is positioned to be lower than a lower end of the center member 95 of the tank protector 90 In this way, it is possible to improve the protection of the dome portions 12 having lower strength than the cylinder portion 11 in the tank 60.As shown in FIG. 5, in the embodiment, the lower end of each end portion member 96 of the tank guard 90 is located below a surface P 3 of the tank. The surface P 3 is situated below the horizontal plane S 1 at an angle of 45° to the central axis CX. That is, even when the tank 60 is applied with an external force from the rear side (the -X axis direction side) to the front side (the +X axis direction side) of the vehicle 100 under the tank guard 90, the horizontal plane S 1 passes through the central axis CX of the tank 60, half of the external force is rejected along the surface of the tank 60.As described above, in the mounting structure for a tank 60 according to the embodiment, the tank guard 90 is fixed to the straps 80. Therefore, when size variations of the tank 60 occur or the tank 60 contracts, the belts 80 and the tank guard 90 "synchronize" with the tank 60, so that it is possible to limit the expansion of the gap between the tank 60 and the tank guard 90. Thereby, the gap is kept as small as possible, and it is possible to prevent a foreign object such as a large stone from being caught in the gap. In particular, in a movable body such as a vehicle, a foreign object such as a large stone may enter the movable body during the movement. However, with the mounting structure for the tank 60 according to the embodiment, it is possible to prevent such a sticking of a foreign matter in the gap between the tank 60 and the tank guard 90. Moreover, by limiting the extent of the gap between the tank 60 and the tank guard 90, the sound that can be generated by the gap is easily addressable.B. Other EmbodimentsIn the above embodiment, the frames 70 are provided on the lower side (the -X axis direction side) of the tank 60, and the belts 80 are provided on the upper side (the +X axis direction side) of the tank 60. However, the invention is not limited thereto. For example, the frames 70 may be provided on the upper side (the +X axis direction side) of the tank 60, and the belts 80 may be provided on the lower side (the -X axis direction side) of the tank 60.In the above embodiment, as a mounting structure for a tank 60, the vehicle 100 to which the tank 60 is mounted will be described by way of example. However, the invention is not limited thereto. For example, the invention can be applied to a movable body other than a vehicle, the movable body using the tank mounting structure 60 according to the embodiment. Further, the mounting structure for a tank 60 can be used in a fixed device. By providing the tank protector 90 on the outside of a part of the tank 60 that allows an impact from the outside, it is possible to efficiently protect the tank 60.In the above embodiment, the spring 84 enables deformation of the band 80 according to expansion or contraction of the tank 60, but the invention is not limited thereto, and other elastic bodies such as rubber may be used instead of the spring 84, and the band 80 itself may be made of an elastic material such as resin.In the foregoing embodiment, each of the straps 80 and the center member 95 of the tank guard 90 are connected together by the bolts 92, 93. However, the invention is not limited thereto, and the straps 80 and the end portion members 96 of the tank guard 90 may be fastened by bolts, respectively. Thus, since the end portion members 96 are thicker than the center member 95, the fuel tank guard 90 is more reliably fixed to the straps 80.

Claims

A mounting structure for a tank (60), comprising: a frame (70) configured to fix the tank (60); a band (80) configured to fix the tank (60) in a state in which the band (80) sandwiches the tank (60) with the frame (70), and the band (80) deforms according to expansion or contraction of the tank (60), wherein one end portion of the band (80) is fixed to the frame (70) via a hinge (82) and a first bolt (83), and the other end portion of the band (80) is fixed to the frame (70) with a second bolt (83) while applying a pressing force to the tank (60) using an elastic body (84); and a tank guard (90) configured to be attached to an outer side of the strap (80).The mounting structure for a tank (60) according to claim 1, wherein the tank protector (90) comprises a center member (95) and end portion members (96), the center member (95) is disposed on an outer side of a cylinder portion (11) which is a cylindrical portion of the tank (60), and the end portion members (96) are respectively disposed on outer sides of dome portions (12), the dome portions (12) being disposed on both end sides of the cylinder portion (11) of the tank (60); and the end portion members (96) are thicker than the center member (95).The mounting structure for a tank (60) according to claim 1 or 2, wherein the shear strength of the tank guard (90) is greater than the shear strength of the band (80).The mounting structure for a tank (60) according to any one of claims 1 to 3, wherein the band (80) is made of metal.The mounting structure for a tank (60) according to any one of claims 1 to 3, wherein the band (80) is made of an elastic resin material.The mounting structure for a tank (60) according to any one of claims 2 to 5, wherein a lower end of each end portion member (96) of the tank guard (90) is positioned lower than a lower end of the central member (95) of the tank guard (90).A vehicle (100) comprising the tank mounting structure (60) according to any one of claims 1 to 6.

Images