Patent Description:
When a railway vehicle or the like travelling at a high speed passes through a tunnel, a sudden pressure change occurs outside the vehicle. Due to such a sudden change of the vehicle-external pressure, the balance between an air-supply amount and a discharge amount for ventilating air inside and outside the vehicle is lost. Accordingly, the vehicle-internal pressure changes, and passengers feel auditory discomfort in some cases.

In view of this, in order to prevent changes of the vehicle-internal pressure, in conventional known ventilation control, a gate valve is provided on an air-supply path and an exhaust path, and when a vehicle passes through a tunnel, the gate valve is closed to stop ventilation temporarily. However, according to the ventilation control, as the length of a tunnel through which a vehicle passes increases, the length of time over which ventilation is stopped also increases. Accordingly, a problem arises that the carbon dioxide concentration inside the vehicle rises, and a clean environment is lost.

To cope with this, Patent Document <NUM> describes a vehicle ventilation system that can reduce discomfort caused by sudden pressure changes inside the vehicle, without stopping ventilation for a long time. According to the vehicle ventilation system disclosed in Patent Document <NUM>, it is possible to obtain the gradient of variations in pressure of air flowing through an air duct that connects the inside of the vehicle and the outside of the vehicle, and to shut off the duct connecting the inside of the vehicle and the outside of the vehicle by a damper in a case where the gradient is equal to or greater than a set value. Thereby, it is possible to prevent increase in the gradient of pressure variations inside the vehicle, and to prevent discomfort that may otherwise be felt by passengers inside the vehicle.

Patent Document <NUM> proposes a ventilation path device for preventing propagation of the differential pressure in a ventilation path. Patent Document <NUM> proposes devices for the prevention of a large amount of air from flowing through a cabin. Patent Document <NUM> proposes a pressure protection device for a rail vehicle. Patent Document <NUM> proposes a method of re-controlling the air volume in a car. Patent Document <NUM> proposes pressure relieving mechanisms for a ventilation system. Patent Document <NUM> proposes a ventilation control method and a ventilation system. Patent Document <NUM> proposes a train ventilator. Patent Document <NUM> proposes a method and a device for preventing fast changes of the atmospheric pressure in an enclosed room induced by an external environment.

Here, in the control performed in the vehicle ventilation system described in Patent Document <NUM>, pressure variations are obtained from sensing values of the pressure provided outside the vehicle, and an air-supply valve and an exhaust valve are shut off in a case where the gradient of variations is equal to or greater than the set value. At this time, if a highly functional blower that does not generate changes in the air volume almost at all in response to pressure variations outside the vehicle is used for the purpose of air supply and air discharge, the pressure inside the vehicle never changes suddenly even if a pressure difference occurs between the pressures inside and outside the vehicle when the valves are opened. However, in a case where such a blower is not used, it is anticipated that a sudden pressure change occurs inside the vehicle in response to a pressure variation outside the vehicle.

An object of the present invention is to provide a rail-vehicle ventilation system that can maintain comfortableness by suppressing sudden pressure variations inside the vehicle, and surely attaining a clean vehicle-internal environment by control of an air-supply valve and an exhaust valve.

In order to solve the problem described above, a rail-vehicle ventilation system is provided according to claim <NUM>.

According to the present invention, it is possible to provide a railway-vehicle ventilation system that can maintain comfortableness by suppressing sudden pressure variations inside the vehicle, and surely attaining a clean vehicle-internal environment by control of an air-supply valve and an exhaust valve.

Problems, configurations and effects other than those described above become apparent from the following explanations of embodiments.

Rail vehicles are vehicles that are operated along constructed tracks, and include railway vehicles, monorail vehicles, streetcars, automated transportation vehicles and the like. Embodiments of the present invention are explained by taking railway vehicles as a representative example of rail vehicles.

In addition, in the present specification, "vehicle-external-pressure information" includes not only sensing values of a vehicle-external-pressure sensor, but also estimates and computed values of the vehicle-external pressure. Accordingly, a "vehicle-external-pressure information acquiring section" includes not only the vehicle-external-pressure sensor, but also all devices that can acquire information for estimating or computing the vehicle-external pressure.

Furthermore, "vehicle-internal-pressure information" includes not only sensing values of a vehicle-internal-pressure sensor, but also estimates and computed values of the vehicle-internal pressure. Accordingly, a "vehicle-internal-pressure information acquiring section" includes not only the vehicle-internal-pressure sensor, but also all devices that can acquire information for estimating or computing the vehicle-internal pressure.

Hereinafter, embodiments of the present invention are explained by using the drawings.

<FIG> is a schematic cross-sectional view of a railway vehicle provided with a ventilation system according to a first embodiment. A railway vehicle <NUM> has an air-supply fan <NUM> that supplies air outside the vehicle to the inside of the vehicle, an air-supply valve <NUM> that can adjust the air-supply flow rate, an exhaust fan <NUM> that discharges air inside the vehicle to the outside of the vehicle, and an exhaust valve <NUM> that can adjust the air-discharge flow rate. The air-supply fan <NUM> and the exhaust fan <NUM> constitute a ventilating section, and the air-supply valve <NUM> and the exhaust valve <NUM> constitute a flow-rate adjusting section.

Note that although a configuration provided with both the air-supply fan <NUM> and the exhaust fan <NUM> is illustrated in <FIG>, another possible configuration is provided only with the air-supply fan <NUM> or only with the exhaust fan <NUM>. In addition, in the configuration illustrated in <FIG>, the air-supply fan <NUM> and the air-supply valve <NUM> are integrated with an air-conditioning device <NUM>, and an exhaust device having the exhaust fan <NUM> and the exhaust valve <NUM> is arranged separately from the air-conditioning device <NUM>.

However, the configuration to be adopted may be any of: a configuration in which the air-supply fan <NUM>, the air-supply valve <NUM>, the exhaust fan <NUM> and the exhaust valve <NUM> are integrated with the air-conditioning device <NUM>; a configuration in which an air-supply device having the air-supply fan <NUM> and the air-supply valve <NUM>, and the exhaust device are both arranged separately from the air-conditioning device <NUM>; a configuration in which a ventilation system having the air-supply device and the exhaust device is arranged separately from the air-conditioning device <NUM>; and a configuration in which the exhaust fan <NUM> and the exhaust valve <NUM> are integrated with the air-conditioning device <NUM>, and the air-supply fan <NUM> and the air-supply valve <NUM> are arranged separately from the air-conditioning device <NUM>. It should be noted, however, that in a case where the air-supply device is arranged separately from the air-conditioning device <NUM>, a configuration may be adopted in which the air-supply device and the air-conditioning device <NUM> communicate with each other via a duct (not illustrated).

Air taken in from the outside of the vehicle by the air-supply fan <NUM> is taken into the air-conditioning device <NUM>. Then, the air is cooled by a heat exchanger <NUM> in the air-conditioning device <NUM> at the time of cooling operation, or is heated by a heater <NUM> in the air-conditioning device <NUM> at the time of heating operation, and then blown out to the inside of the vehicle via a conditioned-air duct <NUM>. The air that has been blown out to the inside of the vehicle and gets to have a high carbon dioxide concentration due to the breathing of passengers is delivered to the outside of the vehicle by the exhaust fan <NUM> via an exhaust duct <NUM>.

The railway vehicle <NUM> is provided with a vehicle-external-pressure sensor <NUM> for sensing the pressure of the outside of the vehicle, and a vehicle-internal-pressure sensor <NUM> for sensing the pressure of the inside of the vehicle. In a suitable configuration, the vehicle-external-pressure sensor <NUM> constituting the vehicle-external-pressure information acquiring section, and the vehicle-internal-pressure sensor <NUM> constituting the vehicle-internal-pressure information acquiring section are provided inside and outside both the front car and the last car of a train of railway vehicles <NUM>, but in another possible configuration, they are provided to the inside and the outside of any vehicle of a train.

Sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM> are input to a control device (control section) <NUM> provided inside the railway vehicle <NUM>. The control device <NUM> receives sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM>, and sends signals for operating the air-supply fan <NUM>, the air-supply valve <NUM>, the exhaust fan <NUM> and the exhaust valve <NUM>. Operation of the control device <NUM> is mentioned in detail below.

<FIG> is a cross-sectional view of the air-supply valve and the exhaust valve used commonly in each embodiment. The air-supply valve <NUM> (or the exhaust valve <NUM>) having the function of the flow-rate adjusting section that adjusts the ventilation flow rate has connecting sections <NUM> provided at both end sections along its flow path, and a valve operation section <NUM> sandwiched by the connecting sections <NUM>. The valve operation section <NUM> includes a valve <NUM> having one end that is retained pivotably, and a drive section (not illustrated) that drives the valve <NUM> on the basis of an instruction from the control device <NUM>. An abutting edge <NUM> of an end section of the connecting section <NUM> on a side where the valve <NUM> is located is provided with a packing <NUM>, and, when the valve <NUM> is closed, the valve <NUM> presses the packing <NUM> to block the flow of air. Note that the valve <NUM> is not limited to a type of valve that is supported pivotably, but may be a type of valve that moves in the direction along the direction of the flow.

By providing packings <NUM> discretely (separately at intervals) in the circumferential direction along the abutting edge <NUM>, it is possible to intentionally allow leaking air <NUM> to flow through gaps between the adjacent packings <NUM>.

Although not illustrated, it is possible to allow the leaking air <NUM> to flow also by providing protrusions and recesses that are discontinuous in the thickness direction at an edge section of the valve <NUM> abutting against the abutting edge <NUM>. Alternatively, a packing <NUM> may be provided continuously in the circumferential direction, and a small opening 72a for the leaking air <NUM> to flow through the closed valve <NUM> may be provided through the valve <NUM>. The leaking air <NUM> is air to be supplied from the outside of the vehicle to the inside of the vehicle, and air to be discharged from the inside of the vehicle to the outside of the vehicle, for ventilation.

Since the flow rate of the leaking air <NUM> is low, it does not cause a large vehicle-internal-pressure variation accompanying a vehicle-external-pressure variation when a railway vehicle passes through a tunnel at a high speed. Accordingly, passengers and the like never feel auditory discomfort. Since ventilation, although at a small flow rate, continues because of the leaking air <NUM> even when the valve <NUM> is closed, the extent of increase in carbon dioxide gas concentration inside the vehicle can be suppressed, and a comfortable vehicle-internal environment can be maintained. Furthermore, by allowing the leaking air <NUM> to flow, even if the state where the valve <NUM> is closed due to malfunction of the drive section or the like continues, a certain extent of ventilation can be continued. Accordingly, sudden deterioration of the vehicle-internal environment can be suppressed.

<FIG> illustrates a control flow of a ventilation method in the first embodiment. First, the control device <NUM> activates the air-supply fan <NUM> and the exhaust fan <NUM>, and opens the air-supply valve <NUM> and the exhaust valve <NUM> to perform ventilation at a first ventilation flow rate.

At Step S5, the control device <NUM> obtains a sensing value of the vehicle-external-pressure sensor <NUM>. At Step S50, the control device <NUM> determines whether or not a vehicle-external-pressure variation is equal to or larger than a preset tolerance on the basis of the obtained sensing value. In a case where it is determined that the vehicle-external-pressure variation is smaller than the preset tolerance, the flow returns to Step S5, and the control device <NUM> receives a next sensing value of the vehicle-external-pressure sensor <NUM>.

On the other hand, in a case where it is determined at Step S50 that the vehicle-external-pressure variation is equal to or larger than the preset tolerance, at Step S55, the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, closes the air-supply valve <NUM> and the exhaust valve <NUM>, and shuts off an air path for communication with the outside of the vehicle or reduces the opening area thereof. Thereby, ventilation is performed at a second ventilation flow rate lower than the first ventilation flow rate.

Here, "shutting off the air path" means air-path restriction that does not allow the leaking air <NUM> to flow, and "reducing the opening area" means air-path restriction that allows the leaking air <NUM> to flow. The same definitions apply also to the following embodiments.

With the ventilation control described above, it is possible to suppress a vehicle-internal-pressure variation resulting from generation of a large difference between the flow rate of air supply to the inside of the vehicle and the flow rate of air discharge to the outside of the vehicle caused by a sudden pressure change occurred outside the vehicle. Note that although, in the control technique illustrated here, when the air-supply valve <NUM> and the exhaust valve <NUM> are operated, the air-supply fan <NUM> and the exhaust fan <NUM> are stopped, a technique of operating the air-supply valve <NUM> and the exhaust valve <NUM> while keeping the air-supply fan <NUM> and the exhaust fan <NUM> running may be used.

Furthermore, at Step S62, the control device <NUM> receives sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM>. At subsequent Step S70, the control device <NUM> calculates the difference between the sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM>, and determined whether or not the difference is within a preset tolerance range. In a case where it is determined that the difference is outside the preset tolerance range (the state where the vehicle-internal/external-pressure difference is large is continuing), the flow returns to Step S62, and the control device <NUM> receives next sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM>.

In contrast to this, in a case where it is determined at Step S70 that the difference is within the preset tolerance range, at Step S75, the control device <NUM> resumes running of the air-supply fan <NUM> and the exhaust fan <NUM>, opens the air-supply valve <NUM> and the exhaust valve <NUM> and restores the ventilation flow rate to the first ventilation flow rate. According to the ventilation control described above, running of the air-supply fan <NUM> and the exhaust fan <NUM> is resumed, and the air-supply valve <NUM> and the exhaust valve <NUM> are opened after checking satisfaction of a condition under which the vehicle-internal pressure does not change suddenly. Accordingly, increase in the vehicle-internal carbon dioxide concentration can be suppressed. Thereafter, the flow returns to Step S5.

<FIG> is a timing chart and a graph illustrating, in association with each other, timings to open and close the air-supply/exhaust valves and the transition of vehicle-internal/external pressures and vehicle-internal carbon dioxide concentration at the time when a railway vehicle to which the first embodiment is applied passes through a tunnel. In <FIG>, in association with time illustrated along the horizontal axis, the opened and closed states of the air-supply valve <NUM> and the exhaust valve <NUM>, changes (dotted line) of a vehicle-external pressure <NUM> when the railway vehicle travels through a tunnel, changes (solid line) of a vehicle-internal pressure <NUM> when the first embodiment is applied, and changes of vehicle-internal carbon dioxide concentration <NUM> are illustrated.

Peaks <NUM> of the vehicle-external pressure occur due to reflection and reciprocation, at the entrance and exit of the tunnel, of a pressure wave generated in the tunnel when the railway vehicle enters the tunnel.

In the example illustrated in <FIG>, the railway vehicle travels a bright section (a space outside the tunnel) from Time T0 to Time T1, travels a tunnel section from Time T1 to Time T7, and travels a bright section again after T7. Hereinafter, ventilation control in the example illustrated in <FIG> is explained in association with the control flow illustrated in <FIG>.

At Time T1, upon entrance of the railway vehicle into the tunnel, when the control device <NUM> determines, in accordance with a sensing value of the vehicle-external-pressure sensor <NUM> (Step S5 in <FIG>), that the vehicle-external-pressure variation is equal to or larger than the tolerance (determination Yes at Step S50 in <FIG>), the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, and closes the air-supply valve <NUM> and the exhaust valve <NUM> (Step S55 in <FIG>).

Furthermore, at Time T2, the control device <NUM> calculates, in accordance with sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM> (Step S62 in <FIG>), the pressure difference therebetween, and when the control device <NUM> determines that the difference between the vehicle-external pressure <NUM> and the vehicle-internal pressure <NUM> is within the tolerance range (determination Yes at Step S70 in <FIG>), the control device <NUM> runs the air-supply fan <NUM> and the exhaust fan <NUM>, and opens the air-supply valve <NUM> and the exhaust valve <NUM> (Step S75 in <FIG>).

In addition, at Time T3, when the control device <NUM> determines, in accordance with a sensing value of the vehicle-external-pressure sensor <NUM> (Step S5 in <FIG>), that a vehicle-external-pressure variation is equal to or larger than the tolerance (determination Yes at Step S50 in <FIG>) due to the vehicle-external pressure lowered accompanying passage of a pressure wave reciprocating in the tunnel, the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, and closes the air-supply valve <NUM> and the exhaust valve <NUM> again (Step S55 in <FIG>).

Furthermore, at Time T4, the control device <NUM> calculates, in accordance with sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM> (Step S62 in <FIG>), the pressure difference therebetween, and when the control device <NUM> determines that the difference between the vehicle-external pressure <NUM> and the vehicle-internal pressure <NUM> is within the tolerance range (determination Yes at Step S70 in <FIG>), the control device <NUM> resumes running of the air-supply fan <NUM> and the exhaust fan <NUM> again, and opens the air-supply valve <NUM> and the exhaust valve <NUM> again (Step S75 in <FIG>).

In addition, at Time T5, when the control device <NUM> determines, in accordance with a sensing value of the vehicle-external-pressure sensor <NUM> (Step S5 in <FIG>), that a vehicle-external-pressure variation is equal to or larger than the tolerance (determination Yes at Step S50 in <FIG>) due to the vehicle-external pressure rose accompanying passage of a pressure wave reciprocating in the tunnel, the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, and closes the air-supply valve <NUM> and the exhaust valve <NUM> again (Step S55 in <FIG>).

Furthermore, at Time T6, the control device <NUM> calculates, in accordance with sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM> (Step S62 in <FIG>), the pressure difference therebetween, and when the control device <NUM> determines that the difference between the vehicle-external pressure <NUM> and the vehicle-internal pressure <NUM> is within the tolerance range (determination Yes at Step S70 in <FIG>), the control device <NUM> resumes running of the air-supply fan <NUM> and the exhaust fan <NUM> again, and opens the air-supply valve <NUM> and the exhaust valve <NUM> again (Step S75 in <FIG>).

In addition, at Time T7, when the control device <NUM> determines, in accordance with a sensing value of the vehicle-external-pressure sensor <NUM> (Step S5 in <FIG>), that the vehicle-external pressure is lowered accompanying passage of a pressure wave reciprocating in the tunnel (determination Yes at Step S50 in <FIG>), the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, and closes the air-supply valve <NUM> and the exhaust valve <NUM> again (Step S55 in <FIG>).

Furthermore, after Time T7, although not illustrated, the control device <NUM> calculates, in accordance with sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM> (Step S62 in <FIG>), the pressure difference therebetween, and when the control device <NUM> determines that the difference between the vehicle-external pressure <NUM> and the vehicle-internal pressure <NUM> is within the tolerance range (determination Yes at Step S70 in <FIG>), the control device <NUM> resumes running of the air-supply fan <NUM> and the exhaust fan <NUM> again, and opens the air-supply valve <NUM> and the exhaust valve <NUM> again (Step S75 in <FIG>), and normal ventilation operation is continued.

According to the present embodiment, even in a case where the railway vehicle is subjected to a sudden change (peak <NUM>) of the vehicle-external pressure <NUM> occurring during passage of the railway vehicle through the tunnel, a sudden change of the vehicle-internal pressure <NUM> is suppressed. Furthermore, during the time period from Time T1 to Time T7 when the railway vehicle passes through the tunnel, the only time periods during which ventilation is stopped are the time periods from Time T1 to Time T2, from Time T3 to Time T4, and from Time T5 to Time T6, and ventilation is resumed during the time periods from Time T2 to Time T3, from Time T4 to Time T5, and from Time T6 to Time T7. Accordingly, significant increase in the vehicle-internal carbon dioxide concentration <NUM> can also be suppressed as illustrated by the graph of the vehicle-internal carbon dioxide concentration <NUM>.

As mentioned above, by shutting off the air-supply valve <NUM> and the exhaust valve <NUM> when the vehicle-external pressure change is equal to or larger than the tolerance, the ventilation flow rate is set to the second ventilation flow rate, and propagation of the sudden pressure change outside the vehicle to the inside of the vehicle is suppressed. Thereafter, when the pressure difference between the inside of the vehicle and the outside of the vehicle is within a tolerance range, the air-supply valve <NUM> and the exhaust valve <NUM> are opened to restore the ventilation flow rate to the first ventilation flow rate. Thereby, sudden pressure changes inside the vehicle that result from opening of the air-supply valve <NUM> described above and the exhaust valve <NUM> described above can be suppressed.

In addition, according to the present embodiment, it is possible to avoid stopping ventilation for a long time. Accordingly, air inside the vehicle can be kept clean. Thereby, a comfortable railway vehicle with suppressed sudden pressure variations and suppressed contamination of the air inside the vehicle can be provided.

<FIG> illustrates a control flow of a ventilation manner in a second embodiment of the present invention. In the first embodiment described above, in a case where a variation in sensing values of the vehicle-external-pressure sensor <NUM> (or the vehicle-external pressure based on the sensing values) is equal to or larger than a preset tolerance, control is executed to send signals to stop the air-supply fan <NUM> and the exhaust fan <NUM> and close the air-supply valve <NUM> and the exhaust valve <NUM> to shut off an air path for communication with the outside of the vehicle or reduce the opening area thereof.

In contrast to this, in the second embodiment, control is executed in a case where the difference between sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM> is equal to or larger than a tolerance range, while the same ventilation system as that in the first embodiment is used.

Explaining more specifically, at Step S6, the control device <NUM> obtains sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM>, and calculates the internal/external-pressure difference. At Step S52, the control device <NUM> determines whether or not the internal/external-pressure difference is equal to or larger than a preset tolerance. In a case where it is determined that the internal/external-pressure difference is smaller than a preset tolerance, the flow returns to Step S6, and the control device <NUM> receives next sensing values of the vehicle-external-pressure sensor <NUM> and the vehicle-internal-pressure sensor <NUM>.

On the other hand, in a case where it is determined at Step S52 that the internal/external-pressure difference is equal to or larger than the preset tolerance, at Step S55, the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, closes the air-supply valve <NUM> and the exhaust valve <NUM>, and shuts off an air path for communication with the outside of the vehicle or reduces the opening area thereof. Subsequent Steps S62, S70 and S75 are similar to those in the first embodiment mentioned above. Accordingly, overlapping explanations are omitted.

Although in the control technique illustrated in the second embodiment mentioned thus far, similar to the first embodiment, the air-supply fan <NUM> and the exhaust fan <NUM> are stopped when the air-supply valve <NUM> and the exhaust valve <NUM> are closed, the air-supply valve <NUM> and the exhaust valve <NUM> may be closed while the air-supply fan <NUM> and the exhaust fan <NUM> are kept running. With the ventilation control mentioned thus far, effects that are equivalent to those in the first embodiment can be attained.

<FIG> is a schematic cross-sectional view of the railway vehicle <NUM> on which a ventilation system according to a third embodiment is mounted. The vehicle-internal-pressure sensor <NUM> that is arranged inside the vehicle in the first embodiment is not provided in the third embodiment. In other respects, the configuration is identical to the configuration in the first embodiment. Accordingly, overlapping explanations are omitted.

<FIG> illustrates a control flow of a ventilation method in the third embodiment. At Step S5, the control device <NUM> obtains a sensing value of the vehicle-external-pressure sensor <NUM>. At Step S50, the control device <NUM> determines whether or not a vehicle-external-pressure variation is equal to or larger than a preset tolerance on the basis of the obtained sensing value. In a case where it is determined that the vehicle-external-pressure variation is smaller than the preset tolerance, the flow returns to Step S5, and the control device <NUM> receives a next sensing value of the vehicle-external-pressure sensor <NUM>.

On the other hand, in a case where it is determined at Step S50 that the vehicle-external-pressure variation is equal to or larger than the preset tolerance, at Step S55, the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, and closes the air-supply valve <NUM> and the exhaust valve <NUM>, to shut off an air path for communication with the outside of the vehicle or reduce the opening area thereof. With the ventilation control described above, it is possible to suppress propagation of sudden pressure changes occurred outside the vehicle to the inside of the vehicle.

Furthermore, at Step S62, the control device <NUM> calculates and estimates the vehicle-internal pressure from a sensing value of the vehicle-external-pressure sensor <NUM> on the basis of simulation, experimental results and the like. That is, the vehicle-external-pressure sensor <NUM> doubles as the vehicle-external-pressure information acquiring section and the vehicle-internal-pressure information acquiring section. At subsequent Step S64, the control device <NUM> calculates the internal/external-pressure difference between the vehicle-external pressure based on the sensing value of the vehicle-external-pressure sensor <NUM> and the estimated vehicle-internal pressure. Note that, instead of Step S50, when it is determined that the difference between the sensing value of the vehicle-external-pressure sensor <NUM> and the estimated vehicle-internal-pressure value is outside the predetermined tolerance range, the control device <NUM> may execute Step S55, and change the ventilation flow rate to the second ventilation flow rate.

In addition, at Step S70, it is determined whether or not the internal/external-pressure difference is within the preset tolerance range. In a case where it is determined that the difference is outside the preset tolerance range, the flow returns to Step S62, and the control device <NUM> executes similar steps.

In contrast to this, in a case where it is determined at Step S70 that the internal/external-pressure difference is within the preset tolerance range, at Step S75, the control device <NUM> resumes running of the air-supply fan <NUM> and the exhaust fan <NUM>, and opens the air-supply valve <NUM> and the exhaust valve <NUM>. With the ventilation control described above, sudden pressure changes inside the vehicle that result from opening of the air-supply valve <NUM> and the exhaust valve <NUM> can be suppressed. Thereafter, the flow returns to Step S5.

According to the third embodiment, in addition to the attainment of effects that are equivalent to those in the first embodiment, the number of parts can be reduced as a result of reduction in the number of sensors since it becomes unnecessary to provide a vehicle-internal-pressure sensor by performing calculation to estimate the vehicle-internal pressure from the vehicle-external-pressure sensor <NUM>. Thereby, the number of parts that may possibly malfunction can be reduced, and highly reliable railway vehicles can be provided.

<FIG> is a schematic cross-sectional view of the railway vehicle <NUM> on which a ventilation system according to a fourth embodiment is mounted. The vehicle-external-pressure sensor <NUM> that is arranged outside the vehicle in the first embodiment is not provided in the third embodiment. In other respects, the configuration is identical to the configuration in the first embodiment. Accordingly, overlapping explanations are omitted.

<FIG> illustrates a control flow of a ventilation method in the fourth embodiment. At Step S6, the control device <NUM> receives a sensing value of the vehicle-internal-pressure sensor <NUM>. At subsequent Step S8, the control device <NUM> calculates the vehicle-external pressure from the sensing value of the vehicle-internal-pressure sensor <NUM> on the basis of simulation, experimental results and the like. At Step S9, the control device <NUM> obtains an estimate of the vehicle-external pressure.

Furthermore, at Step S50, the control device <NUM> determines whether or not a vehicle-external-pressure variation is equal to or larger than a preset tolerance on the basis of the estimate. In a case where it is determined that the vehicle-external-pressure variation is smaller than the preset tolerance, the flow returns to Step S6, and the control device <NUM> receives a next sensing value of the vehicle-internal-pressure sensor <NUM>, and similarly obtains an estimate of the vehicle-external pressure.

On the other hand, in a case where it is determined at Step S50 that the vehicle-external-pressure variation is equal to or larger than the preset tolerance, at Step S55, the control device <NUM> stops the air-supply fan <NUM> and the exhaust fan <NUM>, and closes the air-supply valve <NUM> and the exhaust valve <NUM>, to shut off an air path for communication with the outside of the vehicle or reduce the opening area thereof. With the ventilation control described above, it is possible to suppress propagation of sudden pressure changes occurred outside the vehicle to the inside of the vehicle. Note that, instead of Step S50, when it is determined that the difference between the estimated vehicle-external-pressure value and the sensing value of the vehicle-internal-pressure sensor <NUM> is outside the tolerance range, the control device <NUM> may execute Step S55, and change the ventilation flow rate to the second ventilation flow rate.

Although in the technique illustrated here, a variation in the vehicle-external pressure is calculated from the sensing value of the vehicle-internal-pressure sensor <NUM> (Step S8), and the air-supply fan <NUM> and the exhaust fan <NUM> are stopped depending on the amount of the variation, a technique of controlling the fans to stop depending on a variation in sensing values of the vehicle-internal-pressure sensor <NUM> may be used.

Furthermore, at Step S64, the control device <NUM> calculates the internal/external-pressure difference between the sensing value of the vehicle-internal-pressure sensor <NUM> and the vehicle-external pressure estimated on the basis of the sensing value of the vehicle-internal-pressure sensor <NUM>.

At subsequent Step S72, it is determined whether or not the internal/external-pressure difference is within the preset tolerance range. In a case where it is determined that the internal/external-pressure difference is outside the preset tolerance range, the flow returns to Step S55, and the control device <NUM> executes similar steps.

In contrast to this, in a case where it is determined at Step S72 that the internal/external-pressure difference is within the preset tolerance range, at Step S75, the control device <NUM> runs the air-supply fan <NUM> and the exhaust fan <NUM>, and opens the air-supply valve <NUM> and the exhaust valve <NUM> to open the air path for communication with the outside of the vehicle. With the ventilation control described above, sudden pressure changes inside the vehicle that result from opening of the air-supply valve <NUM> and the exhaust valve <NUM> can be suppressed. Thereafter, the flow returns to Step S6.

According to the fourth embodiment, in addition to the attainment of effects that are equivalent to those in the first embodiment, the number of parts can be reduced as a result of reduction in the number of sensors since it becomes unnecessary to provide a vehicle-internal-pressure sensor by performing calculation to estimate the vehicle-internal pressure from the vehicle-external-pressure sensor <NUM>. Thereby, the number of parts that may possibly malfunction can be reduced, and highly reliable railway vehicles can be provided.

The vehicle-external-pressure sensor <NUM> that is arranged outside the vehicle in the first embodiment is not provided in a fifth embodiment. In other respects, the configuration is identical to the configuration in the first embodiment. Accordingly, overlapping explanations are omitted.

<FIG> illustrates a control flow of a ventilation method in the fifth embodiment. At Step S10, the control device <NUM> acquires geographical point information during travelling of the vehicle. At subsequent Step S30, the control device <NUM> decides whether the vehicle is travelling a tunnel section or a bright section by referring also to tunnel (geographical point) information acquired in advance.

In a case where it is determined that the vehicle is travelling a tunnel section (determination Yes at Step S30), at Step S35, the control device <NUM> doubling as the vehicle-external-pressure information acquiring section calculates the vehicle-external pressure and its variation from the cross-sectional area and/or entire length of the tunnel (tunnel information), and vehicle travel speed information. At Step S40, the control device <NUM> obtains a computed value of the vehicle-external pressure (vehicle-external-pressure information).

At Step S50, the control device <NUM> determines whether or not a vehicle-external-pressure variation is equal to or larger than a preset tolerance on the basis of the computed value. In a case where it is determined that the vehicle-external-pressure variation is smaller than the preset tolerance, the flow returns to Step S10, and similar steps are executed.

On the other hand, in a case where it is determined at Step S50 that the vehicle-external-pressure variation is equal to or larger than the preset tolerance, at Step S55, the control device <NUM> sends signals to stop the air-supply fan <NUM> and the exhaust fan <NUM>, and close the air-supply valve <NUM> and the exhaust valve <NUM> to shut off an air path for communication with the outside of the vehicle or reduce the opening area thereof. With the ventilation control described above, it is possible to suppress propagation of sudden pressure changes occurred outside the vehicle to the inside of the vehicle.

Note that although the decision about a tunnel travelling section, and the computation of the vehicle-external pressure are described above as part of control performed at the control device <NUM> provided in the vehicle, in other possible control, the decision and the computation are performed on the ground side, and the information is transmitted to the vehicle. In addition, by storing the tunnel information, travel speeds, and vehicle-external pressures to be produced under particular corresponding conditions in a database in advance, it is possible to compute the vehicle-external pressure only from geographical point information.

Furthermore, at Step S64, the control device <NUM> calculates the internal/external-pressure difference between the computed value of the vehicle-external pressure, and a sensing value of the vehicle-internal-pressure sensor <NUM> constituting the vehicle-internal-pressure information acquiring section (vehicle-internal-pressure information).

In addition, at Step S72, the control device <NUM> determines whether or not the internal/external-pressure difference is within the preset tolerance range. In a case where it is determined that the internal/external-pressure difference is outside the preset tolerance range, the flow returns to Step S64, and the control device <NUM> continues calculation of the internal/external-pressure difference.

In contrast to this, in a case where it is determined at Step S72 that the internal/external-pressure difference is within the preset tolerance range, at Step S75, the control device <NUM> resumes running of the air-supply fan <NUM> and the exhaust fan <NUM>, and opens the air-supply valve <NUM> and the exhaust valve <NUM> to open the air path for communication with the outside of the vehicle. With the ventilation control described above, sudden pressure changes inside the vehicle that result from opening of the air-supply valve <NUM> and the exhaust valve <NUM> can be suppressed. Thereafter, the flow returns to Step S10.

According to the fifth embodiment, in addition to the attainment of effects that are equivalent to those in the first embodiment, the number of parts can be reduced as a result of reduction in the number of sensors since it becomes unnecessary to provide a vehicle-external-pressure sensor by computing the vehicle-external pressure from the tunnel information and/or the travel speed information. Thereby, the number of parts that may possibly malfunction can be reduced, and highly reliable railway vehicles can be provided.

The vehicle-external-pressure sensor <NUM> that is arranged outside the vehicle, and the vehicle-internal-pressure sensor <NUM> that is arranged inside the vehicle in the first embodiment are not provided in a sixth embodiment. In other respects, the configuration is identical to the configuration in the first embodiment. Accordingly, overlapping explanations are omitted.

<FIG> illustrates a control flow of a ventilation method in the sixth embodiment. At Step S10, the control device <NUM> acquires geographical point information during travelling of the vehicle. At subsequent Step S30, the control device <NUM> decides whether the vehicle is travelling a tunnel section or a bright section by referring also to tunnel information acquired in advance.

In a case where it is determined that the vehicle is travelling a tunnel section (determination Yes at Step S30), at Step S35, the control device <NUM> doubling as the vehicle-external-pressure information acquiring section calculates the vehicle-external pressure and its variation from the cross-sectional area and/or entire length of the tunnel and vehicle travel speed information. At Step S40, the control device <NUM> obtains a computed value of the vehicle-external pressure (vehicle-external-pressure information).

At Step S52, the control device <NUM> determines whether or not the vehicle-external-pressure variation is equal to or larger than a preset tolerance on the basis of the computed value. In a case where it is determined that the vehicle-external-pressure variation is smaller than the preset tolerance, the flow returns to Step S10, and similar steps are executed.

On the other hand, in a case where it is determined at Step S52 that the vehicle-external-pressure variation is equal to or larger than the preset tolerance, at Step S55, the control device <NUM> closes the air-supply valve <NUM> and the exhaust valve <NUM> to shut off an air path for communication with the outside of the vehicle or reduce the opening area thereof. With the ventilation control described above, it is possible to suppress propagation of sudden pressure changes occurred outside the vehicle to the inside of the vehicle.

Furthermore, at Step S64, the control device <NUM> doubling as the vehicle-internal-pressure information acquiring section estimates the vehicle-internal pressure from the computed vehicle-external pressure. At Step S66, the control device <NUM> obtains the internal/external-pressure difference between the computed value of the vehicle-external pressure and the estimate of the vehicle-internal pressure (vehicle-internal-pressure information).

According to the sixth embodiment, in addition to the attainment of effects equivalent to those in the first embodiment, the number of parts can be reduced since pressure sensors become unnecessary by computing the vehicle-external pressure from tunnel information and/or travel speed information and estimating the vehicle-internal pressure from the computed vehicle-external pressure. Thereby, the number of parts that may possibly malfunction can be reduced, and highly reliable railway vehicles can be provided.

As is apparent from the embodiments mentioned thus far, according to the present invention, it is possible to provide a railway-vehicle ventilation system that can maintain comfortableness even in a case where a high-performance blower is not used, by suppressing sudden pressure variations inside the vehicle and suppressing increase in carbon dioxide gas concentration inside the vehicle by control of an air-supply valve provided on an air-supply path and an exhaust valve provided on an exhaust path that are related to ventilation.

Claim 1:
A rail-vehicle ventilation system comprising:
a ventilating section that ventilates air inside and outside a rail vehicle (<NUM>);
a flow-rate adjusting section that adjusts a ventilation flow rate of ventilation by the ventilating section between a first ventilation flow rate and a second ventilation flow rate lower than the first ventilation flow rate;
a control section (<NUM>) that controls the flow-rate adjusting section;
a vehicle-external-pressure information acquiring section (<NUM>) that acquires vehicle-external-pressure (<NUM>) information of the rail vehicle; and
a vehicle-internal-pressure (<NUM>) information acquiring section (<NUM>) that acquires vehicle-internal-pressure information of the rail vehicle, wherein
when it is determined that a difference between the vehicle-external-pressure information and the vehicle-internal-pressure information is within a tolerance range after the flow-rate adjusting section sets the ventilation flow rate to the second ventilation flow rate, the control section controls the flow-rate adjusting section to restore the ventilation flow rate to the first ventilation flow rate
wherein the flow-rate adjusting section includes a connecting section (<NUM>) connected to a duct through which air flows, and a valve operation section (<NUM>) connected to the connecting section, and
wherein the valve operation section includes a movable valve (<NUM>), an abutting edge (<NUM>) against which the valve abuts,
characterised in that either: packings (<NUM>) are provided discretely over an entire circumference of the abutting edge with gaps between adjacent packings for flow of leaking air (<NUM>), or a small opening (72a) is formed through the valve (<NUM>) for flow of leaking air (<NUM>).