Fire-resistant floor structures for railway vehicles

Abstract

A fire-resistant floor structure (10) for a railway vehicle comprises a mounting portion (3) for mounting underfloor equipment (2) on the lower surface (11) of a chassis (1) and a fire-resistant member (4), thereby improving the fire resistance to underfloor fires. The fire-resistant member is a fire-resistant coating (4T) applied to the lower surface of the chassis. The fire-resistant coating (4T) is preferably a foaming fire-resistant coating (4H). A covering body (5) is mounted on the mounting portion to cover an exposed portion (31) exposed from the fire-resistant coating (foaming fire-resistant coating). The underfloor equipment is mounted on the mounting portion via a sealing plate (6).

Description

Technical Field

[0001] The present invention relates to a fire-resistant floor structure for a railway vehicle, and more particularly to a fire-resistant floor structure for a railway vehicle which ensures the freedom of underfloor assembly while improving the fire resistance against underfloor fire. Background Art

[0002] The floor structure of a railway vehicle is generally required to be resistant to fire. In particular, overseas regulations such as NFPA130-Chaper8 in the United States and EN45545-3 in Europe require that, in order to ensure the evacuation time of passengers in the event of a fire under the floor, the floor structure must not collapse within a specified time due to the heating from under the floor and the temperature of the floor surface must be within a specified temperature. Therefore, research is being conducted on fire-resistant floor structures for railway vehicles that have improved fire resistance to underfloor fires.

[0003] For example, Patent Document 1 discloses the following fire-resistant floor structure for a vehicle. That is, a fire-resistant floor structure 100 for a vehicle is disclosed. Fig.13 As shown, the upper layer 101, the middle layer 102 and the lower layer 103 are composed of the upper layer 101 as the main component, the middle layer 102 is in contact with the entire surface of the upper layer 101 to support it, at least the middle layer 102 and the lower layer 103 are composed of non-combustible materials, and the heat insulating material layer 104 is provided between the middle layer 102 and the lower layer 103, the lower layer 103 is fixed to the mounting portion 105 provided on the middle layer 102 or the connecting member 106 installed on the middle layer 102, and the mounting portion 105 or the connecting member 106 is formed with a T-shaped groove with a wide depth for mounting the bolt head of the underfloor equipment, so that the groove is exposed to the outside. Here, the middle layer 102 is formed of a block of an aluminum extruded profile, the lower layer 103 is formed of a stainless steel plate, and the heat insulating material layer 104 is formed of glass fiber or ceramic fiber.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Publication No. 5-84345 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] However, the fire-resistant floor structure 100 of the vehicle disclosed in Patent Document 1 has the following problem. That is, the fire-resistant floor structure 100 is provided with a heat-insulating material layer 104 formed of glass fiber or ceramic fiber and a lower layer 103 formed of a stainless steel plate on the lower side of a middle layer 102 formed of a block of an aluminum extruded profile, so the space below the middle layer 102 is narrowed by the thickness of the heat-insulating material layer 104 and the like (for example, about 60 mm), thereby causing a problem that the degree of freedom in installing underfloor equipment is reduced.

[0009] In addition, the lower layer 103 is fixed to the mounting portion 105 provided on the middle layer 102 or the connecting member 106 installed on the middle layer 102, and a deep and wide T-shaped groove for the bolt head for installing the underfloor equipment is formed on the mounting portion 105 or the connecting member 106, and the groove is exposed to the outside. Therefore, with regard to the heating from under the floor, there is a problem that the heat is transferred to the middle layer 102 through the groove exposed to the outside, and the temperature of the upper surface of the floor is likely to rise.

[0010] The present invention is made to solve such problems, and its purpose is to provide a fire-resistant floor structure for railway vehicles that can ensure the freedom of installing underfloor equipment on the one hand, and can suppress the invasion of heat from under the floor to the upper surface of the floor on the other hand, thereby improving the fire resistance.

[0011] Technical means of solving problems

[0012] (1) One form of the present invention for solving the above-mentioned problem is a fire-resistant floor structure of a railway vehicle, which has a mounting portion for underfloor equipment and a fire-resistant member provided on the lower surface of a chassis, thereby improving the fire resistance to underfloor fires. The main idea is that the fire-resistant member is a fire-resistant coating applied to the lower surface of the chassis, and a covering body is installed on the mounting portion to cover the exposed portion exposed from the fire-resistant coating.

[0013] According to the above aspect, the refractory member is a refractory coating applied to the lower surface of the chassis, so the refractory member can be formed thinner than the heat insulating material layer formed of glass fiber or ceramic fiber, thereby increasing the space under the chassis. Therefore, on the one hand, it is possible to suppress the intrusion of heat from the lower surface of the chassis, and on the other hand, it is possible to increase the degree of freedom in installing underfloor equipment.

[0014] In addition, a covering body is installed on the mounting portion to cover the exposed portion exposed from the fire-resistant paint. Therefore, the covering body installed on the mounting portion blocks the heat from the underfloor, and the heat is not easily transferred to the chassis through the mounting portion. Therefore, it is possible to avoid the premature melting of the fire-resistant paint applied to the lower surface of the chassis. As a result, the fire-resistant performance of the fire-resistant paint applied to the lower surface of the chassis can be maintained for a long time, and the temperature rise of the upper surface of the floor can be delayed, so that the evacuation time for passengers and crew members can be ensured.

[0015] Therefore, according to one aspect of the present invention, a fire-resistant floor structure for a railway vehicle can be provided which can ensure the freedom of installing underfloor equipment while suppressing the invasion of heat from underfloor to the upper surface of the floor and improving the fire resistance.

[0016] (2) In the fire-resistant floor structure for a railway vehicle according to (1), it is preferred that the underfloor equipment is provided in the mounting portion via a sealing plate.

[0017] According to the above aspect, the underfloor equipment is installed on the mounting portion via the baffle plate, so even if the underfloor equipment burns quickly and falls, the baffle plate will remain installed on the mounting portion, thereby maintaining a state in which heat is not easily transferred to the chassis via the mounting portion. Therefore, the temperature rise of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew can be ensured.

[0018] (3) In the fire-resistant floor structure for a railway vehicle according to (2), the baffle plate is preferably formed of a material having a lower thermal conductivity than the mounting portion.

[0019] According to the above aspect, the baffle is formed of a material having a lower thermal conductivity than the mounting portion, so that the heat from under the floor can be transmitted to the mounting portion more difficultly through the baffle. Therefore, the rise in temperature of the upper surface of the floor can be further delayed, and deformation is not easy, and the fire resistance of the baffle can be maintained for a long time. As a result, deformation of the chassis and rise in temperature of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew can be ensured.

[0020] (4) In the fire-resistant floor structure for a railway vehicle according to any one of (1) to (3), the fire-resistant paint is preferably applied to the covering body.

[0021] According to the above aspect, the fire-resistant coating is applied to the covering body, so the heat from under the floor can be further blocked by the fire-resistant coating applied to the covering body. Therefore, the deformation of the chassis and the temperature rise of the upper surface of the floor can be further delayed, ensuring the evacuation time for passengers and crew members.

[0022] (5) In the fire-resistant floor structure for a railway vehicle according to any one of (1) to (4), the fire-resistant coating material is preferably a foaming fire-resistant coating material.

[0023] According to the above-mentioned form, the refractory coating is a foaming refractory coating, so when heated to a predetermined temperature, the inside is foamed and bulged, thereby forming a heat insulating layer. With the help of this heat insulating layer, the intrusion of heat from the lower surface of the chassis can be further suppressed. In addition, the foaming refractory coating in the coated state can be formed thinner than the insulating material layer such as glass fiber, so that the space under the chassis can be increased. As a result, on the one hand, the intrusion of heat from the lower surface of the chassis can be suppressed, and on the other hand, the degree of freedom of installing underfloor equipment can be further increased.

[0024] (6) In the fire-resistant floor structure for a railway vehicle according to any one of (1) to (5), the covering body is preferably formed of a material having a lower thermal conductivity than the mounting portion.

[0025] According to the above aspect, the cover is formed of a material having a lower thermal conductivity than the mounting portion, so that the heat from under the floor is less likely to be transferred to the mounting portion through the cover, thereby further delaying the rise in the temperature of the upper surface of the floor.

[0026] (7) A fire-resistant floor structure for a railway vehicle according to any one of (2) to (6), wherein the chassis is preferably formed of an aluminum alloy extruded profile, the mounting portion has a hanging groove, the hanging groove is formed in a T-shape in a convex portion that protrudes downward from the lower surface of the chassis along the front-rear direction of the vehicle in an integral manner with the chassis, and the underfloor equipment is fastened to the mounting portion via the sealing plate by a hanging bolt whose head is inserted into the hanging groove.

[0027] According to the above-mentioned form, the chassis is formed of an aluminum alloy extruded profile, and the mounting portion is provided with a hanging groove, which is formed in a T-shape in a convex portion protruding downward from the lower surface of the chassis along the front-rear direction of the vehicle in an integral manner with the chassis, and the underfloor equipment is fastened to the mounting portion via a sealing plate by a hanging bolt whose head is inserted into the hanging groove. Therefore, on the one hand, the chassis can be made lighter and the mounting portion can be made stronger, and on the other hand, the underfloor equipment can be set at any position in the front-rear direction of the vehicle. Therefore, it is easy to cope with changes or increases or decreases in the installation position of the underfloor equipment. As a result, on the one hand, the fire resistance of the underfloor can be improved, and on the other hand, the degree of freedom in setting the underfloor equipment can be further increased.

[0028] (8) In the fire-resistant floor structure of a railway vehicle according to (7), preferably, a heat insulating member having a lower thermal conductivity than the hanging bolt is installed between the hanging bolt seat surface of the hanging groove and the head of the hanging bolt.

[0029] According to the above aspect, a heat insulating member having a lower thermal conductivity than the hanging bolt is installed between the hanging bolt seat surface of the hanging groove and the head of the hanging bolt, so that heat from under the floor can be prevented from being directly transferred to the hanging bolt seat surface of the hanging groove via the hanging bolt. Therefore, heat is not easily transferred to the chassis where the hanging groove is formed, and the temperature rise of the chassis can be further delayed. As a result, the deformation of the chassis and the temperature rise of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0030] (9) According to the fire-resistant floor structure of a railway vehicle described in (7) or (8), it is preferred that the seat surface for the hanging bolts and the seat surface for the sealing plate of the mounting portion are not coated with the fire-resistant paint or the foaming fire-resistant paint.

[0031] According to the above aspect, the seat surface for the hanging bolt of the installation part and the seat surface for the baffle plate are not coated with refractory paint or foaming refractory paint, so it is possible to prevent the hanging bolts fastening the underfloor equipment to the installation part from loosening due to shrinkage of the refractory paint or foaming refractory paint over the years. Therefore, it is possible to reduce the inspection work of the hanging bolts fastening the underfloor equipment.

[0032] (10) In the fire-resistant floor structure for a railway vehicle according to any one of (7) to (9), an air layer is preferably formed between the covering body and the side wall of the convex portion.

[0033] According to the above aspect, an air layer is formed between the cover and the side wall of the convex part, so that the heat from under the floor can be further blocked by the air layer formed between the cover and the convex part. Therefore, the deformation of the chassis and the temperature rise of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0034] Effects of the Invention

[0035] According to the present invention, a fire-resistant floor structure for a railway vehicle can be provided which can ensure the freedom of installing underfloor equipment while suppressing the invasion of heat from underfloor to the upper surface of the floor and improve the fire resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a cross-sectional view of a main part of an example of a fire-resistant floor structure of a railway vehicle according to an embodiment of the present invention.

[0037] Figure 2 for Figure 1 Bottom view from perspective A shown.

[0038] Figure 3 for Figure 2 An enlarged view of section C is shown.

[0039] Figure 4 for Figure 3 DD cross section shown.

[0040] Figure 5 for Figure 4 The exploded assembly diagram of the hanging slot, hanging bolts and insulation components shown in the figure, Figure 5 (a) shows the state before the hanging bolts and the insulation member are inserted into the hanging groove. Figure 5 (b) shows the state after the hanging bolts and the insulation member are inserted into the hanging grooves.

[0041] Figure 6 for Figure 1 An enlarged cross-sectional view of portion B is shown.

[0042] Figure 7 for Figure 6 Bottom view from perspective E shown.

[0043] Figure 8 for Figure 4 FIG. 1 is an enlarged cross-sectional view of another example of the fastening portion of the underfloor equipment shown.

[0044] Fig. 9 for Figure 1 An enlarged cross-sectional view of the first modified example at portion B shown.

[0045] Fig.10 for Figure 1 An enlarged cross-sectional view of the second modified example at portion B shown.

[0046] Fig.11 for Figure 1 An enlarged cross-sectional view of the third modified example at portion B shown.

[0047] Fig.12 For explanation Figure 1 A schematic cross-sectional view showing the melting-off phenomenon of the foaming fire-resistant coating in a comparative example of the fire-resistant floor structure of the present railway vehicle shown in FIG. Fig.12 (a) is a cross-sectional view showing a state in which a foamable refractory coating is applied to the lower surface of the chassis with the mounting portion exposed, Fig.12 (b) is a cross-sectional view showing a state of heating from under the floor, Fig.12 (c) is a cross-sectional view showing a state in which heat is transferred from the mounting portion to the lower surface of the base frame and foaming has spread on the upper surface side of the foamable refractory coating. Fig.12 (d) is a cross-sectional view showing a state where most of the foamable refractory coating material has been melted off.

[0048] Fig.13 This is a cross-sectional view of a main part of the fire-resistant floor structure of a vehicle disclosed in Patent Document 1. DETAILED DESCRIPTION

[0049] Next, the fire-resistant floor structure of the railway vehicle of the present embodiment will be described in detail with reference to the accompanying drawings. Specifically, after a specific example of the fire-resistant floor structure of the railway vehicle of the present embodiment is described in detail, its modified examples (first modified example to third modified example) will be described. In addition, the melting-off phenomenon of the foaming fire-resistant coating in the comparative example of the fire-resistant floor structure of the railway vehicle will be described.

[0050] <Specific example of the fire-resistant floor structure of the present railway vehicle>

[0051] First, use Figures 1 to 8 , a specific example of the fire-resistant floor structure of the railway vehicle according to the present embodiment will be described. Figure 1 A cross-sectional view of a main part showing an example of a fire-resistant floor structure of a railway vehicle according to an embodiment of the present invention. Figure 2 exhibit Figure 1 Bottom view from perspective A shown. Figure 3 exhibit Figure 2 An enlarged view of section C is shown. Figure 4 exhibit Figure 3 DD cross section shown. Figure 5 exhibit Figure 4 The exploded assembly view of the hanging slots, hanging bolts and insulation components shown. Figure 5 (a) Shows the state before the hanging bolts and insulation components are inserted into the hanging grooves. Figure 5 (b) shows the state after the hanging bolts and the insulation member are inserted into the hanging groove. Figure 6 exhibit Figure 1 An enlarged cross-sectional view of portion B is shown. Figure 7 exhibit Figure 6 Bottom view from perspective E shown. Figure 8 exhibit Figure 4 FIG. 1 is an enlarged cross-sectional view of another example of the fastening portion of the underfloor equipment shown.

[0052] like Figure 1 to Figure 7 As shown, the fire-resistant floor structure 10 of the railway vehicle of this embodiment includes a mounting portion 3 for installing the underfloor equipment 2 on the lower surface 11 of the chassis 1 and a fire-resistant member 4, which improves the fire resistance of the underfloor fire, wherein the fire-resistant member 4 is a fire-resistant paint 4T applied to the lower surface 11 of the chassis 1. In addition, a covering body 5 is installed on the mounting portion 3 to cover the exposed portion 31 exposed from the fire-resistant paint 4T. As a result, the fire-resistant paint 4T applied to the lower surface 11 of the chassis 1 can be prevented from melting off prematurely. As a result, the fire resistance of the fire-resistant paint 4T can be maintained for a long time, the temperature rise of the upper surface of the floor can be delayed, and the evacuation time for passengers and crew members can be ensured.

[0053] Here, if Figure 1 , Figure 2 As shown, the mounting portion 3 is formed as a plurality of protrusions 3T that protrude downward from the lower surface 11 of the chassis 1 and extend in the front-rear direction of the vehicle. The fire-resistant paint 4T is applied to the entire lower surface 11 of the chassis 1 except for the protrusions 3T. The covering body 5 is formed as a long strip of an inverted hat-shaped cross section that is open at the top so as to include the installation location of the underfloor equipment 2 and cover the entire protrusion for each of the protrusions 3T. In addition, since the long strip covering body 5 is installed on the mounting portion 3, when the underfloor equipment 2 is newly added or moved to another location, the covering body 5 at the corresponding location can be changed or modified.

[0054] In addition, if Figure 3 , Figure 4 As shown, the underfloor equipment 2 is preferably installed on the mounting portion 3 via a sealing plate 6. The sealing plate 6 is formed into a rectangular flat plate with a length that can correspond to the installation portion 21 of the underfloor equipment 2. Here, the sealing plate 6 and the cover 5 are sandwiched between the installation portion 21 of the underfloor equipment 2 and the mounting portion 3. In this case, even if the underfloor equipment 2 burns quickly and falls, the sealing plate 6 and the cover 5 will remain in a state of being clamped on the mounting portion 3, thereby maintaining a state in which heat is not easily transferred to the chassis 1 through the mounting portion 3.

[0055] Furthermore, it can also be like Figure 8 As shown in another example, the fire-resistant paint 4T is applied to the side wall 31H of the protrusion 3T of the mounting portion 3 to which the underfloor equipment 2 is fastened. In this case, the underfloor equipment 2 is also provided on the mounting portion 3 via the baffle plate 6, so the covering body 5 that covers the exposed portion exposed from the fire-resistant paint 4T may not be installed on the mounting portion 3.

[0056] In addition, the baffle plate 6 is preferably formed of a material having a lower thermal conductivity than the mounting portion 3. Thus, the heat from under the floor can be transferred to the mounting portion 3 more difficultly through the baffle plate 6. Therefore, the temperature rise of the upper surface of the floor can be further delayed. In addition, in this case, the baffle plate 6 is not easily deformed even when heated, and the fire resistance of the baffle plate 6 can be maintained for a long time.

[0057] In addition, the refractory coating 4T is preferably a foamable refractory coating 4H: when heated to a predetermined temperature, the interior is foamed and bulged, thereby forming an insulating layer. The insulating layer formed by the foaming can further suppress the invasion of heat from the lower surface 11 of the chassis 1. Here, the foamable refractory coating 4H is preferably an epoxy foamable refractory coating (product "Sikagard-831" sold by Sika Co., Ltd. of Japan), but other foamable refractory coatings can also be used.

[0058] The coating thickness of the foamable refractory coating 4H is preferably about 4 to 5 mm, but can be set as appropriate according to the required fire resistance. The coating of the foamable refractory coating 4H can be formed by spraying, etc. When the foamable refractory coating 4H is heated to 200 to 300°C, the coating will be thickened by about 20 to 30 times.

[0059] In addition, if Figures 1 to 8 As shown, the chassis 1 is preferably formed of an aluminum alloy extruded profile 1K, but may also be formed of other structural members (iron frame materials, etc.). The chassis 1 formed of an aluminum alloy extruded profile is preferably a so-called double-shell structure consisting of an upper plate 1a on the floor surface side, a lower plate 1b on the underside of the floor, and a connecting plate 1c connecting the upper plate 1a and the lower plate 1b in a truss shape. A refractory paint 4T (foaming refractory paint 4H) is applied to the lower plate 1b.

[0060] Since the base frame 1 is the above-mentioned double-layer shell structure formed by the aluminum alloy extruded profile 1K, it is easy to achieve lightweight and high strength, and the hollow part formed between the upper plate 1a and the lower plate 1b and the connecting plate 1c functions as an insulating layer of air. Therefore, the heat from under the floor is not easily transferred to the floor, which can delay the temperature rise on the floor.

[0061] In addition, side beams 12 protruding downward are formed at both ends of the chassis 1 in the vehicle width direction. The side beams 12 are formed of an aluminum alloy extruded profile into a double-layer shell structure. In addition, it is preferred that the inner wall surface 121 of the side beam 12 is also coated with a fire-resistant paint 4T (foaming fire-resistant paint 4H). Thereby, the heat insulation of the side body structure 9 formed above the side beam 12 can be improved.

[0062] In addition, the mounting portion 3 preferably includes a hanging groove 3M formed in a T-shape in a convex portion 3T that protrudes downward in the vehicle front-rear direction integrally with the chassis 1. In this case, a rectangular space is formed at the top of the hanging groove 3M. The underfloor equipment 2 is fastened to the mounting portion 3 via the blocking plate 6 by a hanging bolt 7 whose head 71 is inserted into the rectangular space of the hanging groove 3M. The head 71 is formed in a rectangular shape along the hanging groove 3M, so that when the nut 74 is engaged with the threaded portion 72 of the hanging bolt 7, it does not rotate idly in the hanging groove 3M.

[0063] Furthermore, the underfloor equipment 2 can be installed at any position in the front-rear direction of the vehicle by means of the hanging groove 3M. Therefore, it is possible to easily cope with the change or increase or decrease of the installation position of the underfloor equipment 2. Figure 2 As shown, at the lower end of the mounting portion 3, a hanging bolt insertion opening 3S is formed at an appropriate position, and the hanging bolt insertion opening 3S is formed so that the head 71 of the hanging bolt 7 can be inserted into the hanging groove 3M.

[0064] In addition, if Figure 4 , Figure 5 As shown, a heat insulating member 73 having a lower thermal conductivity than the hanging bolt 7 is installed between the hanging bolt seat surface 3Z1 of the hanging groove 3M and the head 71 of the hanging bolt 7. The heat insulating member 73 is formed as a rectangular flat plate, and a through hole 731 is formed in the center thereof for the threaded portion 72 of the hanging bolt 7 to pass through.

[0065] The heat insulating member 73 can prevent the heat from being directly transferred from the underfloor to the hanging bolt seat surface 3Z1 of the hanging groove 3M via the hanging bolt 7. The heat insulating member 73 does not need to be particularly limited in material, but is preferably made of stainless steel or the like having the following properties: lower thermal conductivity than the ordinary carbon steel hanging bolt 7 and the aluminum alloy chassis 1, and less shrinkage due to aging.

[0066] On the other hand, it is preferred that the refractory paint 4T (foaming refractory paint 4H) is not coated on the seat surface 3Z1 for the hanging bolt and the seat surface 3Z2 for the baffle plate of the installation portion 3. The reason for this is that it is possible to prevent the refractory paint 4T (foaming refractory paint 4H) from shrinking over time and causing the hanging bolts 7 that fasten the underfloor equipment 2 to loosen. As a result, it is possible to reduce the maintenance work on the hanging bolts 7 that fasten the underfloor equipment 2. Furthermore, the underfloor equipment 2 is usually fastened to the installation portion 3 by a plurality of hanging bolts 7.

[0067] As described above, the mounting portion 3 is provided with a covering body 5 for covering the exposed portion 31 exposed from the refractory paint 4T (foaming refractory paint 4H). Figure 1 , Figure 6 As shown, it is preferred that a refractory coating 4T (foaming refractory coating 4H) is coated on the covering body 5. Here, the covering body 5 coated with the refractory coating 4T (foaming refractory coating 4H) is formed in advance, and after the foaming refractory coating 4H is coated on the lower surface 11 of the chassis 1, the covering body 5 coated with the refractory coating 4T (foaming refractory coating 4H) is installed on the installation portion 3.

[0068] like Figure 6 , Figure 7As shown, the cover 5 is mounted on the mounting portion 3 by a fastener 54 engaged with the hanging groove 3M. The fastener 54 includes a fastener body 541 formed in a V shape, a clamping claw 542 formed at the upper end of the fastener body 541, and a supporting claw 543 formed at the middle part of the fastener body 541, and is formed by a spring member. The fastener body 541 is inserted into the insertion hole 5S of the cover 5, the clamping claw 542 is engaged with the hanging bolt seat 3Z1 of the hanging groove 3M, and the supporting claw 543 supports the cover 5 coated with the fire-resistant paint 4T (foaming fire-resistant paint 4H). By means of the cover 5 coated with the fire-resistant paint 4T (foaming fire-resistant paint 4H), the effect of preventing heat from being easily transferred to the base frame 1 via the mounting portion 3 can be further improved for heating from under the floor.

[0069] In addition, the covering body 5 is preferably formed of a raw material having a lower thermal conductivity than the mounting portion 3. For example, in the case where the mounting portion 3 and the chassis 1 are integrally formed of an aluminum alloy extruded profile 1K, the covering body 5 is preferably formed of stainless steel. In this case, for heating from under the floor, the heat can be less likely to be transferred to the mounting portion 3 by the stainless steel covering body 5 having low thermal conductivity. Therefore, the temperature rise on the upper surface of the floor can be further delayed. In addition, the covering body 5 is preferably formed of a raw material having a higher strength than the mounting portion 3 or a raw material that is not easily damaged or deformed (such as FRP (fiber reinforced plastic) or steel plate, or a laminated structure thereof, etc.). As a result, it is less likely to be damaged or deformed by gravel or the like that bounces up during driving, and the fire resistance of the covering body 5 can be maintained for a long time.

[0070] In addition, the cover 5 is formed into an inverted hat-shaped cross section, and includes a bottom plate portion 51 that abuts against the lower surface of the mounting portion 3 (the seat surface 3Z2 for the baffle plate), an inclined plate portion 52 that extends obliquely toward the lower surface 11 of the chassis 1 on both sides of the bottom plate portion 51, and a pad portion 53 that extends horizontally from the inclined plate portion 52 and abuts against the refractory paint 4T (foaming refractory paint 4H) applied to the lower surface 11 of the chassis 1. Furthermore, in the present embodiment, the cover 5 is mounted on the mounting portion 3 by means of a fastener 54 that engages with the hanging groove 3M, but the fastener 54 may also be a bolt, a rivet, a clip, or the like.

[0071] Here, if Figure 4 , Figure 6 As shown, an air layer 8 is formed between the inclined plate portion 52 of the cover 5 and the side wall 31H of the convex portion 3T of the mounting portion 3. Therefore, with respect to the heat from under the floor, the air layer 8 formed between the cover 5 and the mounting portion 3 can further block the invasion of heat. As a result, the deformation of the chassis 1 and the increase in the temperature of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0072] <Modification of fire-resistant floor structure of railway vehicle>

[0073] Next, use Figures 9 to 11 , modifications (first to third modifications) of the fire-resistant floor structure of the railway vehicle according to the present embodiment will be described. Fig. 9 exhibit Figure 1 An enlarged cross-sectional view of the first modified example at portion B shown. Fig.10 exhibit Figure 1 An enlarged cross-sectional view of the second modified example at portion B shown. Fig.11 exhibit Figure 1 The enlarged cross-sectional view of the third modification example at the portion B shown in FIG. The first to third modifications are described here, but other modifications are also possible as long as they are within the scope of the gist of the present invention.

[0074] (First Modification)

[0075] like Fig. 9 As shown, in the first variant of the fire-resistant floor structure 10 of the railway vehicle, the refractory paint 4T (foaming refractory paint 4H) is not applied to the covering body 5. Here, the covering body 5 is pre-formed into a predetermined shape, and after the refractory paint 4T (foaming refractory paint 4H) is applied to the lower surface 11 of the chassis 1 as the refractory member 4, the covering body 5 is mounted to the mounting portion 3. The covering body 5 is mounted on the mounting portion 3 by means of a fastener 54 engaged with the hanging groove 3M. Furthermore, an air layer 8 is formed between the inclined plate portion 52 of the covering body 5 and the side wall 31H of the mounting portion 3. In this first variant, the heat intrusion from the heating under the floor is suppressed by the covering body 5 and the air layer 8. Therefore, the deformation of the chassis 1 and the rise in the temperature of the upper surface of the floor can be delayed, and the evacuation time for passengers and crew members can be ensured.

[0076] (Second Modification)

[0077] like Fig.10As shown, in the second variant of the fire-resistant floor structure 10 of the railway vehicle, a fire-resistant coating 4T (foaming fire-resistant coating 4H) is applied to both the lower surface 11 of the chassis 1 and the covering body 5 as a fire-resistant member 4. Here, the covering body 5 is fixed to the lower surface 11 of the chassis 1 by rivets 55 or the like in advance. Thereafter, the fire-resistant coating 4T (foaming fire-resistant coating 4H) is applied to both the lower surface 11 of the chassis 1 and the covering body 5 at the same time. In this second variant, the heat intrusion from the heating under the floor can be further blocked by the fire-resistant coating 4T (foaming fire-resistant coating 4H) applied to both the lower surface 11 of the chassis 1 and the covering body 5. Therefore, the deformation of the chassis 1 and the rise in the temperature of the upper surface of the floor can be further delayed, ensuring the evacuation time for passengers and crew members. Furthermore, the refractory coating 4T (foaming refractory coating 4H) can be applied to the covering body 5 at the same time as the refractory coating 4T (foaming refractory coating 4H) is applied to the lower surface 11 of the base frame 1, thereby reducing the labor and time of separately applying the refractory coating 4T (foaming refractory coating 4H) to the covering body 5.

[0078] (Third Modification)

[0079] like Fig.11 As shown, in the third modification of the fire-resistant floor structure 10 of the present railway vehicle, the fire-resistant paint 4T (foaming fire-resistant paint 4H) is not applied to the cover 5. Here, the bottom plate portion 51 of the cover 5 is fastened to the mounting portion 3 via the baffle plate 6 by the hanging bolt 7 whose head 71 is inserted into the hanging groove 3M of the mounting portion 3. Therefore, the cover 5 and the baffle plate 6 are doubled to suppress the invasion of heat from the mounting portion 3. In addition, an air layer 8 is formed between the inclined plate portion 52 of the cover 5 and the side wall 31H of the mounting portion 3. In this third modification, the invasion of heat from the mounting portion 3 can be further blocked by the cover 5, the baffle plate 6 and the air layer 8 for heating from under the floor. Therefore, the deformation of the chassis 1 and the increase in the temperature of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured. Furthermore, the installation of the cover 5 uses the hanging bolt 7, and the fastener 54 is not required, so the parts for installing the cover 5 can be simplified.

[0080] <Comparative example of fire-resistant floor structure of railway vehicles>

[0081] Next, use Fig.12 , a comparative example of the fire-resistant floor structure of the railway vehicle according to the present embodiment will be described. Fig.12 Display pair Figure 1 Schematic cross-sectional view for explaining the melting-off phenomenon of the foaming fire-resistant coating in the comparative example of the fire-resistant floor structure of the present railway vehicle shown in FIG. Fig.12 (a) is a cross-sectional view showing a foamable refractory coating applied to the lower surface of the chassis with the mounting portion exposed, Fig.12 (b) A cross-sectional view showing the state of heating from under the floor, Fig.12 (c) a cross-sectional view showing a state where heat is transferred from the mounting portion to the base frame and foaming has spread on the upper surface side of the foamable refractory coating, Fig.12 (d) A cross-sectional view showing a state where most of the foaming refractory coating has melted off.

[0082] like Fig.12 As shown in (a), the common point between this comparative example and this embodiment is that the lower surface 11 of the base frame 1 is coated with a foaming refractory paint 4H, but the difference is that the covering body 5 for covering the exposed portion 31 exposed from the foaming refractory paint 4H is not installed on the mounting portion 3. Fig.12 As shown in (b), when heated from under the floor, in the initial stage of heating, foaming expands in the lower part 4H1 of the foamable fire-resistant coating 4H. However, when the heating from under the floor continues, as shown in FIG. Fig.12 As shown in (c), heat is transferred from the exposed portion 31 of the mounting portion 3 to the chassis 1, and the temperature of the lower surface 11 of the chassis 1 rises rapidly and exceeds the foaming start temperature of the foaming refractory paint 4H. Therefore, the foaming continues to expand in the upper portion 4H2 of the foaming refractory paint 4H that contacts the lower surface 11 of the chassis 1. The density of the foamed and expanded upper portion 4H2 decreases, and the strength decreases significantly. As a result, the foaming refractory paint 4H can no longer support its own weight, as shown in FIG. Fig.12 As shown in (d), the foaming fire-resistant coating 4H becomes a state where most of the upper part 4H2 is melted away, leaving only a part of the upper part 4H2 (melting away phenomenon). Thus, the deformation of the underframe 1 and the rise in the temperature of the upper surface of the floor are promoted, making it difficult to ensure the evacuation time for passengers and crew members.

[0083] In contrast, according to the fire-resistant floor structure 10 of the railway vehicle of the present embodiment, as described above, the cover 5 that covers the exposed portion 31 exposed from the foaming fire-resistant paint 4H is installed on the mounting portion 3, so the cover 5 installed on the mounting portion 3 blocks the heat from the underfloor, and the heat is not easily transferred to the chassis 1 through the mounting portion 3. Therefore, the temperature of the lower surface 11 of the chassis 1 rises slowly and does not easily reach the foaming start temperature of the foaming fire-resistant paint 4H, so the foaming fire-resistant paint 4H applied to the lower surface 11 of the chassis 1 can be prevented from melting within a predetermined time. As a result, the deformation of the chassis 1 and the increase in the temperature of the upper surface of the floor can be delayed, and the evacuation time for passengers and crew members can be ensured.

[0084] <Effects>

[0085] According to the fire-resistant floor structure 10 of the railway vehicle of the present embodiment described in detail above, the fire-resistant member 4 is the fire-resistant coating 4T applied to the lower surface 11 of the chassis 1, so the fire-resistant member 4 can be formed thinner than the heat insulating material layer formed of glass fiber or ceramic fiber, so that the space under the chassis 1 can be increased. Therefore, on the one hand, the intrusion of heat from the lower surface 11 of the chassis 1 can be suppressed, and on the other hand, the degree of freedom of installing the underfloor equipment 2 can be increased.

[0086] Furthermore, since the cover 5 that covers the exposed portion 31 exposed from the fire-resistant paint 4T is mounted on the mounting portion 3, the cover 5 mounted on the mounting portion 3 blocks the heat from the underfloor, and the heat is not easily transferred to the chassis 1 via the mounting portion 3. Therefore, the melting of the fire-resistant paint 4T applied to the lower surface 11 of the chassis 1 can be avoided. As a result, the fire-resistant performance of the fire-resistant paint 4T applied to the lower surface 11 of the chassis 1 can be maintained for a long time, and the temperature rise of the upper surface of the floor can be delayed, so that the evacuation time for passengers and crew members can be ensured.

[0087] Therefore, according to the present embodiment, it is possible to provide a fire-resistant floor structure 10 for a railway vehicle which can ensure the freedom of installing the underfloor equipment 2 while suppressing the invasion of heat from under the floor toward the upper surface of the floor and improving the fire resistance.

[0088] Furthermore, according to the present embodiment, the underfloor equipment 2 is installed on the mounting portion 3 via the baffle plate 6, so even if the underfloor equipment 2 burns quickly and falls, the baffle plate 6 will remain installed on the mounting portion 3, thereby maintaining a state in which heat is not easily transferred to the chassis 1 via the mounting portion 3. Therefore, the temperature rise of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0089] Furthermore, according to the present embodiment, the baffle plate 6 is formed of a material having a lower thermal conductivity than the mounting portion 3, so that heat from under the floor can be transferred to the mounting portion 3 more difficultly through the baffle plate 6. Therefore, the rise in the temperature of the upper surface of the floor can be further delayed, and deformation is not easy, and the fire resistance of the baffle plate 6 can be maintained for a long time. As a result, the deformation of the chassis 1 and the rise in the temperature of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0090] Furthermore, according to the present embodiment, the fire-resistant paint 4T is applied to the cover 5, so that the heat from under the floor can be further blocked by the fire-resistant paint 4T applied to the cover 5. Therefore, the deformation of the chassis 1 and the temperature rise of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0091] Furthermore, according to the present embodiment, the refractory coating 4T is a foaming refractory coating 4H, so when heated to a predetermined temperature, the inside is foamed and bulged, thereby forming a heat insulating layer. With the help of this heat insulating layer, the intrusion of heat from the lower surface 11 of the chassis 1 can be further suppressed. Therefore, the foaming refractory coating 4H in the coated state can be formed thinner than the heat insulating material layer such as glass fiber, so that the space under the chassis 1 can be increased. As a result, on the one hand, the intrusion of heat from the lower surface of the chassis 1 can be suppressed, and on the other hand, the degree of freedom of setting the underfloor equipment 2 can be further increased.

[0092] Furthermore, according to this embodiment, since the cover 5 is formed of a material having a lower thermal conductivity than the mounting portion 3, the heat from under the floor is less likely to be transferred to the mounting portion 3 through the cover 5. Therefore, the temperature rise of the upper surface of the floor can be further delayed.

[0093] Furthermore, according to the present embodiment, the chassis 1 is formed of an aluminum alloy extruded profile 1K, and the mounting portion 3 is provided with a hanging groove 3M, which is formed in a T-shape in a convex portion 3T that protrudes downward from the lower surface 11 of the chassis 1 in the vehicle front-rear direction in an integral manner with the chassis 1, and the underfloor equipment 2 is fastened to the mounting portion 3 via the baffle plate 6 by the hanging bolt 7 whose head 71 is inserted into the hanging groove 3M. Therefore, on the one hand, the chassis 1 can be made lighter and the mounting portion 3 can be made stronger, and on the other hand, the underfloor equipment 2 can be set at any position in the vehicle front-rear direction. Therefore, it is easy to cope with changes or increases or decreases in the installation position of the underfloor equipment 2. As a result, on the one hand, the fire resistance of the underfloor can be improved, and on the other hand, the degree of freedom in setting the underfloor equipment 2 can be further increased.

[0094] Furthermore, according to the present embodiment, the heat insulating member 73 having a lower thermal conductivity than the hanging bolt 7 is installed between the hanging bolt seat surface 3Z1 of the hanging groove 3M and the head 71 of the hanging bolt 7, so that the heat from under the floor can be prevented from being directly transferred to the hanging bolt seat surface 3Z1 of the hanging groove 3M via the hanging bolt 7. Therefore, the heat is not easily transferred to the chassis 1 formed with the hanging groove 3M, and the temperature rise of the chassis 1 can be further delayed. As a result, the deformation of the chassis 1 and the temperature rise of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0095] Furthermore, according to the present embodiment, the refractory paint 4T or the foaming refractory paint 4H is not applied to the seat surface 3Z1 for the hanging bolt and the seat surface 3Z2 for the baffle plate of the installation portion 3, so that the refractory paint 4T or the foaming refractory paint 4H can be prevented from shrinking due to the change over time and causing the hanging bolts 7 that fasten the underfloor equipment 2 to the installation portion 3 to loosen. Therefore, the maintenance work on the hanging bolts 7 that fasten the underfloor equipment 2 can be reduced.

[0096] Furthermore, according to the present embodiment, an air layer 8 is formed between the cover 5 and the side wall 31H of the convex portion 3T, so that the heat from under the floor can be further blocked by the air layer 8 formed between the cover 5 and the convex portion 3T. Therefore, the deformation of the chassis 1 and the increase in the temperature of the upper surface of the floor can be further delayed, and the evacuation time for passengers and crew members can be ensured.

[0097] Industrial Applicability

[0098] The present invention can be used as a fire-resistant floor structure of a railway vehicle which ensures the freedom of underfloor assembly on the one hand and improves the fire resistance against underfloor fire on the other hand.

[0099] Explanation of symbols

[0100] 1… bottom frame

[0101] 1K...Extrusion profile

[0102] 2…Underfloor equipment

[0103] 3…Installation

[0104] 3M…Hanging slot

[0105] 3T…convex part

[0106] 3Z1…Seating surface for hanging bolts

[0107] 3Z2… Seat surface for baffle

[0108] 4…Refractory components

[0109] 4T…Refractory coating

[0110] 4H…Foaming refractory coating

[0111] 5… Covering body

[0112] 6…Baffle

[0113] 7…Hanging bolt

[0114] 8…Air layer

[0115] 10…Fire-resistant floor structures for railway vehicles

[0116] 31…exposed part

[0117] 31H…Sidewall

[0118] 71…Head

[0119] 73…Insulation components

Claims

1. A fire-resistant floor structure of a railway vehicle, comprising an underframe having a lower surface, a mounting portion of underfloor equipment and a fire-resistant member being arranged on the lower surface of the underframe, thereby improving the fire resistance to underfloor fires, characterized in that: The refractory component is a refractory coating applied to the lower surface of the chassis. The mounting portion is provided with a covering body for covering the exposed portion exposed from the refractory coating. The underframe is formed of an aluminum alloy extruded profile, and the mounting portion includes a hanging groove formed in a T-shape in a convex portion protruding downward from a lower surface of the underframe in a vehicle front-rear direction integrally with the underframe. The underfloor equipment is fastened to the mounting portion via a sealing plate by means of a hanging bolt whose head is inserted into the hanging groove. A heat insulating member having a lower thermal conductivity than the hanging bolt is installed between a hanging bolt seat surface of the hanging groove and a head of the hanging bolt.

2. The fire-resistant floor structure of a railway vehicle according to claim 1, characterized in that: The blocking plate is formed of a material having a lower thermal conductivity than the mounting portion.

3. The fire-resistant floor structure of a railway vehicle according to claim 1, characterized in that: The covering body is coated with the refractory coating.

4. The fire-resistant floor structure of a railway vehicle according to any one of claims 1 to 3, characterized in that: The refractory coating is a foaming refractory coating.

5. The fire-resistant floor structure of a railway vehicle according to claim 1, characterized in that: The cover body is formed of a material having a lower thermal conductivity than the mounting portion.

6. The fire-resistant floor structure of a railway vehicle according to claim 4, characterized in that: The refractory paint is not applied to the seat surface for the hanging bolts and the seat surface for the sealing plate of the installation portion.

7. The fire-resistant floor structure of a railway vehicle according to any one of claims 1, 3 and 5, characterized in that: An air layer is formed between the cover and the side wall of the convex portion.

Images