Patent Description:
In recent years, vehicles running on liquid hydrogen have been used. <CIT> discloses an on-vehicle fuel tank composed of an inner casing that contains liquid hydrogen, and an outer casing that supports the inner casing via a vacuum heat-insulation layer. <CIT> discloses a hydrogen storage system for a vehicle. Other fuel supply systems are disclosed by <CIT> and <CIT>.

The vehicles running on liquid hydrogen are equipped with a liquid hydrogen tank, a vaporizer that vaporizes liquid hydrogen, and a hydrogen supply unit that fills a space with vaporized hydrogen gas and supplies the filled hydrogen gas to a fuel cell, hydrogen engine, or the like. It is desired to prevent or reduce damage to such a hydrogen supply unit in the event of a vehicle collision.

An object of the present invention is therefore to prevent or reduce damage to the hydrogen supply unit in the event of a vehicle collision.

A vehicle comprising a hydrogen engine and an on-vehicle hydrogen supply apparatus according to the present disclosure includes a hydrogen supply unit that includes a liquid hydrogen tank, a vaporizer that vaporizes liquid hydrogen, and a pressure chamber that is filled with vaporized hydrogen gas and supplies the filled hydrogen gas to a hydrogen engine for driving a vehicle, and supplies the hydrogen gas vaporized from the liquid hydrogen to the hydrogen engine. The on-vehicle hydrogen supply apparatus also includes a cover that houses the hydrogen supply unit.

As such, the hydrogen supply unit is housed in the cover and mounted on the vehicle, and this makes it possible to prevent or reduce damage to the hydrogen supply unit in the event of a vehicle collision.

In the on-vehicle hydrogen supply apparatus according to the present invention the cover for the hydrogen supply unit includes a partition plate that separates an interior space into a first space that houses the liquid hydrogen tank and a second space that houses the vaporizer and the pressure chamber.

As such, the partition plate is located between the liquid hydrogen tank and the pressure chamber and between the liquid hydrogen tank and the vaporizer to separate the space that houses them, and this makes it possible to prevent contact between the liquid hydrogen tank and the pressure chamber and between the liquid hydrogen tank and the vaporizer in the event of a vehicle collision, thereby preventing or reducing damage thereto.

In the on-vehicle hydrogen supply apparatus according to the present invention, the hydrogen supply unit may include a pressure reducing valve that is located above the vaporizer in the second space and reduces the pressure of the hydrogen gas filled in the pressure chamber, and the cover may include a stay that extends into the second space and supports an upper part of the pressure reducing valve.

This makes is possible to prevent oscillation of an upper end of the pressure reducing valve, which may otherwise cause damage to the pressure reducing valve in the event of a vehicle collision.

In the on-vehicle hydrogen supply apparatus according to the present invention, the cover may include a lower cover that houses a lower part of the liquid hydrogen tank and has, at its rear side, a pedestal on which the vaporizer is mounted, an upper cover that is assembled to the upper side of the lower cover so as to cover an upper part of the liquid hydrogen tank and houses the pressure chamber therein, and a rear cover that is attached to the upper side of the pedestal of the lower cover so as to cover the vaporizer mounted on the pedestal and is connected to a rear end of the upper cover.

As such, the cover is composed of the lower cover, the upper cover, and the rear cover, and this allows the cover to house the hydrogen supply unit easily even if the shape of the hydrogen supply unit is complicated.

In the on-vehicle hydrogen supply apparatus according to the present invention, the liquid hydrogen tank has a cylindrical shape, and the partition plate has a flat section that is attached to the upper side of the lower cover and covers the upper part of the liquid hydrogen tank, and a curved section that curves downward from the flat section along an outer circumference of the liquid hydrogen tank and extends to a front end of the pedestal of the lower cover. The first space is a space on the lower side of the partition plate, and the second space is a space on the upper and rear sides of the partition plate. The pressure chamber may be located between the partition plate and a ceiling plate of the upper cover, and the vaporizer may be located between the partition plate and the rear cover.

As such, the pressure chamber and the vaporizer are located between the partition plate and the upper cover or the rear cover, and this makes it possible to prevent direct transmission of impact force to the pressure chamber and the vaporizer in the event of a vehicle collision, thereby preventing or reducing damage to the pressure chamber and the vaporizer.

In the on-vehicle hydrogen supply apparatus according to the present invention, the hydrogen supply unit may include a pressure reducing valve that is located above the vaporizer in the second space and reduces the pressure of the hydrogen gas filled in the pressure chamber, and the rear cover may include a stay that extends into the second space and supports an upper part of the pressure reducing valve.

This makes it possible to prevent oscillation of an upper end of the pressure reducing valve which may cause damage to the pressure reducing valve in the event of a vehicle collision.

In the on-vehicle hydrogen supply apparatus according to the present invention, the upper cover, the lower cover, and the rear cover may be made of CFRP. The partition plate may also be made of CFRP.

By forming the covers and the partition plate from such a high-strength material, damage to the hydrogen supply unit housed in the cover can be effectively prevented or reduced in the event of a vehicle collision.

According to the present disclosure, it is possible to prevent or reduce damage to the hydrogen supply unit in the event of a vehicle collision.

An embodiment of the present disclosure will be described based on the following figures, wherein:.

Hereinafter, an on-vehicle hydrogen supply apparatus <NUM> according to an embodiment will be described with reference to the drawings. In the drawings, arrows "FR," "UP," and "RH" respectively represent the front side, the upper side, and the right side of the on-vehicle hydrogen supply apparatus <NUM>. The directions opposite to the arrows "FR," "UP," and "RH" respectively represent the rear side, the lower side, and the left side of the on-vehicle hydrogen supply apparatus <NUM>. Hereinafter, when the description is given simply using front and rear, right and left, and up and down directions, they respectively indicate front and rear in the front-and-rear direction, right and left in the right-and-left direction, and up and down in the up-and-down direction of the on-vehicle hydrogen supply apparatus <NUM>, unless otherwise mentioned. The on-vehicle hydrogen supply apparatus <NUM> is mounted on a vehicle such that its front side is at the front side of the vehicle (traveling direction), its upper side is at the upper side of the vehicle, and its right side is at the right side of the vehicle. Therefore, when the on-vehicle hydrogen supply apparatus <NUM> is mounted on the vehicle, its front side, upper side, and right side are respectively located at the front side, the upper side, and the right side of the vehicle.

As shown in <FIG>, the on-vehicle hydrogen supply apparatus <NUM> is composed of a hydrogen supply unit <NUM> that supplies hydrogen gas vaporized from liquid hydrogen to a hydrogen engine for driving the vehicle, and a cover <NUM> that houses the hydrogen supply unit <NUM>. The cover <NUM> is composed of a lower cover <NUM>, an upper cover <NUM>, and a rear cover <NUM>.

Before describing the details of the cover <NUM>, the hydrogen supply unit <NUM> will be described in detail with reference to <FIG> and <FIG>. As shown in <FIG> and <FIG>, the hydrogen supply unit <NUM> is composed of a liquid hydrogen tank <NUM>, a vaporizer <NUM>, a pressure chamber <NUM>, a pressure reducing valve <NUM>, a liquid hydrogen pump <NUM>, and pipes <NUM> to <NUM>.

The liquid hydrogen tank <NUM> is an insulated tank that contains low-temperature liquid hydrogen. The liquid hydrogen tank <NUM> is a cylindrical tank with dish-shaped mirror plates attached to both ends. The liquid hydrogen pump <NUM> is located inside the liquid hydrogen tank <NUM> and applies pressure to liquid hydrogen to transfer it to the vaporizer <NUM>. The vaporizer <NUM> vaporizes liquid hydrogen to hydrogen gas by heat exchange between liquid hydrogen flowing from the liquid hydrogen tank <NUM> and helium gas heated by a heater (not shown). Helium gas enters the vaporizer <NUM> through a helium gas inlet pipe <NUM> and returns to the heater through a helium gas return pipe <NUM> (see <FIG>).

The pressure chamber <NUM> is filled with hydrogen gas that flows from the vaporizer <NUM>. Hydrogen gas filled in the pressure chamber <NUM> is supplied to the hydrogen engine through the pressure reducing valve <NUM>. The pressure chamber <NUM> is a cylindrical chamber with full hemispherical mirror plates attached to both ends. The mirror plate on the right side of the pressure chamber <NUM> has a pipe connection seat <NUM> attached thereto. The pressure reducing valve <NUM> has a valve body 65a, and an actuator 65b that protrudes upward. The pressure reducing valve <NUM> reduces the pressure of the high pressure hydrogen gas flowing from the pressure chamber <NUM> to the supply pressure of hydrogen gas to be supplied to the hydrogen engine.

The liquid hydrogen pump <NUM> in the liquid hydrogen tank <NUM> is connected to the vaporizer <NUM> via the liquid hydrogen discharge pipe <NUM> and the vaporizer inlet pipe <NUM>. The vaporizer <NUM> is connected to the pressure chamber <NUM> via the hydrogen gas filler pipe <NUM>. The pressure chamber <NUM> is connected to the pressure reducing valve <NUM> via the hydrogen gas outlet pipe <NUM>. After the pressure reducing valve <NUM> reduces the pressure of hydrogen gas, the resulting hydrogen gas is supplied to the hydrogen engine through the hydrogen gas supply pipe <NUM>.

Returning to <FIG>, the cover <NUM> will now be described in detail. As described above, the cover <NUM> is composed of the lower cover <NUM>, the upper cover <NUM>, and the rear cover <NUM>. First, the external shapes of the lower cover <NUM>, the upper cover <NUM>, and the rear cover <NUM> will be described.

The lower cover <NUM> has a square box shape with an open top surrounded by a bottom plate <NUM>, a lower front plate <NUM>, a lower rear plate <NUM>, and lower right and left side plates <NUM>. The height of the lower rear plate <NUM> is lower than the height of the lower front plate <NUM>. Upper ends of the lower right and left side plates <NUM> slope downward from the front to the rear. A plate-like pedestal <NUM> is attached to the rear side of the lower rear plate <NUM> of the lower cover <NUM> so as to protrude rearward. Rear parts of the lower right and left side plates <NUM> extend onto the pedestal <NUM> and are connected to right and left ends of the pedestal <NUM>. The lower cover <NUM>, the upper cover <NUM>, the rear cover <NUM>, and the pedestal <NUM> are made of carbon fiber reinforced plastics (hereinafter referred to as CFRP).

The upper cover <NUM> is composed of a ceiling plate <NUM>, an upper front plate <NUM>, and upper right and left side plates <NUM>. The height of the upper right and left side plates <NUM> is higher in the rear than in the front, and lower ends of the upper right and left side plates <NUM> slope downward from the front to the rear. The upper cover <NUM> is assembled to the upper side of the lower cover <NUM> such that a lower end of the upper front plate <NUM> comes into contact with an upper end of the lower front plate <NUM> of the lower cover <NUM> and lower ends of the upper right and left side plates <NUM> come into contact with upper ends of the lower right and left side plates <NUM>. When the upper cover <NUM> and the lower cover <NUM> are assembled vertically, they form a square box shape where the rear side of the upper cover <NUM> is open.

The rear cover <NUM> is composed of a rear ceiling plate <NUM>, a rear plate <NUM>, and rear right and left side plates <NUM>. Like the rear parts of the lower right and left side plates <NUM> of the lower cover <NUM>, lower ends of the rear right and left side plates <NUM> slope downward from the front to the rear. The rear cover <NUM> is assembled to the lower cover <NUM> and the upper cover <NUM> such that a front end of the rear ceiling plate <NUM> comes into contact with a rear end of the ceiling plate <NUM>, front ends of the rear right and left side plates <NUM> come into contact with rear ends of the upper right and left side plates <NUM> and the lower right and left side plates <NUM>, lower ends of the rear right and left side plates <NUM> come into contact with upper ends of portions of the lower right and left side plates <NUM> that extend above the pedestal <NUM>, and that a lower end of the rear plate <NUM> comes into contact with an upper end of the pedestal <NUM>.

When the lower cover <NUM>, the upper cover <NUM>, and the rear cover <NUM> are assembled, they form the cover <NUM>, which has a square box shape with a portion protruding rearward, as shown in <FIG>.

Next, the internal structure of the cover <NUM> will be described with reference to <FIG>. As shown in <FIG> and <FIG>, a tank receiving plate <NUM> is mounted inside the lower cover <NUM>. The tank receiving plate <NUM> has a cylindrical surface to receive the liquid hydrogen tank <NUM>. As shown in <FIG>, the tank receiving plate <NUM> is connected to the lower right and left side plates <NUM> and to the bottom plate <NUM> via a plurality of supporting members (not shown). As shown in <FIG> and <FIG>, an upper front end of the tank receiving plate <NUM> and the upper end of the lower front plate <NUM> are connected by a connecting plate <NUM>. The tank receiving plate <NUM> receives the lower part of the liquid hydrogen tank <NUM>. The vaporizer <NUM> is mounted on the pedestal <NUM> on the rear side of the tank receiving plate <NUM>. Furthermore, a groove-shaped frame <NUM> with an open bottom is mounted above the pedestal <NUM> so as to straddle the vaporizer <NUM>. The pressure reducing valve <NUM> is mounted on the frame <NUM>.

The rear cover <NUM> has a stay <NUM> protruding forward from the rear plate <NUM> inside the rear cover <NUM>. The stay <NUM> supports the actuator 65b of the pressure reducing valve <NUM> when the rear cover <NUM> is assembled to the lower cover <NUM> and the upper cover <NUM>.

As shown in <FIG> and <FIG>, a partition plate <NUM> is provided on the upper side of the lower cover <NUM>. The partition plate <NUM> has a flat section <NUM>, a curved section <NUM>, and a post <NUM>. The flat section <NUM> is a section attached to the upper side of the lower cover <NUM> and covers the upper part of the liquid hydrogen tank <NUM>. The curved section <NUM> is a section that curves downward from the flat section <NUM> along the outer circumference of the liquid hydrogen tank <NUM> and extends to the front end of the pedestal <NUM> of the lower cover <NUM>. As shown in <FIG>, the width of the partition plate <NUM> in the right-and-left direction is smaller than the widths of the inner surfaces of the upper cover <NUM> and the lower cover <NUM> in the right-and-left direction.

The post <NUM> connects the front end of the flat section <NUM> to the connecting plate <NUM> of the lower cover <NUM> to support the flat section <NUM>. The lower end of the curved section <NUM> is connected to the lower rear plate <NUM> of the lower cover <NUM>. A base <NUM> for supporting the pressure chamber <NUM> is mounted on the upper surface of the curved section <NUM> of the partition plate <NUM>. The pressure chamber <NUM> is mounted on the upper side of the base <NUM>.

The liquid hydrogen tank <NUM> is received in the tank receiving plate <NUM> of the lower cover <NUM>, as indicated by an arrow <NUM> in <FIG>. The partition plate <NUM> is attached to the connecting plate <NUM> and the lower rear plate <NUM> of the lower cover <NUM> so as to cover the top of the liquid hydrogen tank <NUM>, as indicated by arrows <NUM> in <FIG>. The upper cover <NUM> is placed over the partition plate <NUM> and the pressure chamber <NUM> from above as indicated by arrows <NUM> in <FIG> and is assembled to the lower cover <NUM> such that its lower ends come into contact with the upper ends of the lower cover <NUM>. When assembled on top of the lower cover <NUM>, the upper cover <NUM> covers the upper part of the liquid hydrogen tank <NUM> and houses the pressure chamber <NUM> therein. The rear cover <NUM> is assembled to the lower cover <NUM> and the upper cover <NUM> so as to cover the vaporizer <NUM> and the pressure reducing valve <NUM> from above and behind, as indicated by arrows <NUM> in <FIG>.

As such, when the components constituting the hydrogen supply unit <NUM> are housed in the interior space of the cover <NUM>, the lower cover <NUM>, the lower half of the upper cover <NUM>, and the partition plate <NUM> define a first space <NUM>. The first space <NUM> is a space located on the lower side of the partition plate <NUM>. The first space <NUM> houses the liquid hydrogen tank <NUM>.

The partition plate <NUM>, the pedestal <NUM>, the upper half of the upper cover <NUM>, and the rear cover <NUM> define a second space <NUM>. The second space <NUM> is a space on the upper and rear sides of the partition plate <NUM>. The second space <NUM> houses the pressure chamber <NUM> and the vaporizer <NUM>. The pressure chamber <NUM> is located between the partition plate <NUM> and the ceiling plate <NUM> of the upper cover <NUM>. The vaporizer <NUM> and the pressure reducing valve <NUM> are located between the partition plate <NUM> and the rear plate <NUM> of the rear cover <NUM>.

As such, the partition plate <NUM> separates the interior space of the cover <NUM> into the first space <NUM> that houses the liquid hydrogen tank <NUM> and the second space <NUM> that houses the vaporizer <NUM> and the pressure chamber <NUM>. The stay <NUM> attached to the rear cover <NUM> fits into the circumference of the actuator 65b of the pressure reducing valve <NUM> to thereby support the actuator 65b in the front and back direction and the right and left direction.

As described above, the on-vehicle hydrogen supply apparatus <NUM> is mounted on the vehicle with the hydrogen supply unit <NUM> housed in the cover <NUM>, and this prevents or reduces damage to the hydrogen supply unit <NUM> in the event of a vehicle collision. The on-vehicle hydrogen supply apparatus <NUM> also has the partition plate <NUM> that separates the interior space of the cover <NUM> into the first space <NUM> where the liquid hydrogen tank <NUM> is housed and the second space <NUM> where the pressure chamber <NUM> and the vaporizer <NUM> are housed. This makes it possible to prevent contact between the liquid hydrogen tank <NUM> and the pressure chamber <NUM> and between the liquid hydrogen tank <NUM> and the vaporizer <NUM> in the event of a vehicle collision, thereby preventing or reducing damage thereto.

In addition, the cover <NUM> is composed of the lower cover <NUM>, the upper cover <NUM>, and the rear cover <NUM>, and this allows the cover <NUM> to house the hydrogen supply unit <NUM> even if the shape of the hydrogen supply unit <NUM> is complicated.

Furthermore, the pressure chamber <NUM> and the vaporizer <NUM> are located between the partition plate <NUM> and the upper cover <NUM> or the rear cover <NUM>, and this makes it possible to prevent direct transmission of impact force to the pressure chamber <NUM> and the vaporizer <NUM> in the event of a vehicle collision, thereby preventing or reducing damage to the pressure chamber <NUM> and the vaporizer <NUM>.

Claim 1:
A vehicle comprising:
a hydrogen engine; and
an on-vehicle hydrogen supply apparatus (<NUM>) mounted on the vehicle such that its front side is at the front side of the vehicle, its upper side is at the upper side of the vehicle, and its right side is at the right side of the vehicle;
the on-vehicle hydrogen supply apparatus comprising:
a hydrogen supply unit (<NUM>) that
comprises a liquid hydrogen tank (<NUM>), a vaporizer (<NUM>) that vaporizes liquid hydrogen, and a pressure chamber (<NUM>) that is filled with vaporized hydrogen gas and supplies the filled hydrogen gas to the hydrogen engine for driving the vehicle, and
supplies the hydrogen gas vaporized from the liquid hydrogen to the hydrogen engine; and
a cover (<NUM>) that houses the hydrogen supply unit, wherein the cover (<NUM>) for the hydrogen supply unit includes a partition plate (<NUM>) that separates an interior space into a first space that houses the liquid hydrogen tank (<NUM>) and a second space that houses the vaporizer (<NUM>) and the pressure chamber (<NUM>).