EP0620392A1 - Vorrichtung zum Vermeiden oder Begrenzen von plötzlichen Druckänderungen in Fahrzeugen, insbesondere in Landfahrzeugen - Google Patents

Vorrichtung zum Vermeiden oder Begrenzen von plötzlichen Druckänderungen in Fahrzeugen, insbesondere in Landfahrzeugen Download PDF

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Publication number
EP0620392A1
EP0620392A1 EP94400777A EP94400777A EP0620392A1 EP 0620392 A1 EP0620392 A1 EP 0620392A1 EP 94400777 A EP94400777 A EP 94400777A EP 94400777 A EP94400777 A EP 94400777A EP 0620392 A1 EP0620392 A1 EP 0620392A1
Authority
EP
European Patent Office
Prior art keywords
vehicle
external
pressure
event
blade
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP94400777A
Other languages
English (en)
French (fr)
Inventor
Jean-Pierre C/O Gec Alsthom Budliger
Gérard c/o Gec Alsthom Capitaine
Stephen C/O Gec Alsthom Haentjens
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alstom Transport SA
Original Assignee
GEC Alsthom Transport SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by GEC Alsthom Transport SA filed Critical GEC Alsthom Transport SA
Publication of EP0620392A1 publication Critical patent/EP0620392A1/de
Withdrawn legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B61—RAILWAYS
    • B61D—BODY DETAILS OR KINDS OF RAILWAY VEHICLES
    • B61D27/00—Heating, cooling, ventilating, or air-conditioning
    • B61D27/0009—Means for controlling or equalizing air pressure shocks in trains, e.g. when passing or crossing in tunnels

Definitions

  • the invention relates to a device for suppressing or limiting sudden variations in pressure in vehicles, in particular in land vehicles. It applies in particular to high-speed trains.
  • a vehicle moving in the atmosphere is subjected to pressure forces, the distribution of which on the external wall depends on the shape of the latter and the speed of advance.
  • this vehicle passes near an obstacle (entrance to a tunnel, bridge, various objects in the vicinity of the traffic lane, ...) or when crossing another vehicle, there is a variation in the field aerodynamic speeds that the vehicle drives with it. This then results in rapid variations in pressure on the external walls of the vehicle. This effect is all the more pronounced as the vehicle speed is higher, the pressure variation being approximately proportional to the square of the speed.
  • Document EP-A-315 108 also discloses a device for regulating the air flow placed in the ventilation circuit of a railway vehicle.
  • This device comprises two flexible blades each arranged on opposite sides of a duct of the ventilation circuit. Depending on the difference between internal and external pressures in the vehicle, the blades can bend, thus reducing the passage offered to the air flow.
  • This system is simple but requires substantial clearance for the movement of the blades which gives it poor airtightness and makes it ineffective for high pressure differences.
  • EP-A-498554 also discloses a device for controlling the air flow in the ventilation duct of a high-speed train. It includes a flexible blade which curves according to the difference between the external and internal pressures of a vehicle. From a certain threshold the blade actuates the switch of an electrical circuit which controls the closing of the ventilation duct. A timer imposes a determined closing time before reopening the duct.
  • This device is complicated since it requires a pressure detector, a signal processing circuit, an electrically controlled closure system and an artificial delay circuit.
  • the present invention makes it possible to remedy all of these drawbacks in a simple and inexpensive manner. It offers a passive type system, therefore requiring no detector, electronic control circuit or actuator. This system is effective for high pressure differences. It can be used for all the ducts of the a Vogellic circuit which must be used in a rail vehicle body, in the presence or absence of fans. It can also be used for conduits carrying other fluids, condensates for example.
  • the shutter element can be a piece that fits into the duct, pierced with a light for the passage of the air flow and of which said receiving face, into which the light opens, is a concave curved face.
  • the partition being a blade articulated by two of its opposite sides.
  • the device may include two shutter elements each formed in one piece fitting into the duct, pierced with a light for the passage of the air flow and of which said receiving face, into which the light opens, is a concave curved face, the receiving faces of the two obturation elements being opposite, the partition being a blade articulated by two of its opposite sides and situated between the two receiving faces, the blade having a position of rest between the two receiving faces in case of balance between the pressures internal and external to the vehicle and being plated on one or the other of the reception faces in the event of rapid variation between the pressures internal and external to the vehicle.
  • the blade can be articulated by means of elastic means so that it can, in the event of rapid variation between the pressures internal and external to the vehicle, completely obstruct the light of a shutter element.
  • the blade and its articulation means can be provided so that, in the event of rapid variation between the pressures internal and external to the vehicle, the blade only partially obstructs the light of a shutter element so that the device constitutes a air flow rate limiting valve.
  • the blade can be articulated by means of elastic means so that it can, in the event of rapid variation between the pressures internal and external to the vehicle, completely obstruct the light of one of the shutter elements, the device comprising means so that, in the event of rapid variation between the pressures internal and external to the vehicle, the blade only partially obstructs the light from the other shutter element.
  • the device may comprise two shutter elements each formed in one piece fitting into the duct, pierced with a light for the passage of the air flow, the light opening into said receiving face, the faces of reception of the two elements being opposite, the partition being a blade fixed by one of its sides and capable, in the event of rapid variation between the pressures internal and external to the vehicle, to be pressed against the face of reception of one of the shutter elements to completely obstruct its light in the event of pressure variation in a given direction and to be pressed against the receiving face of the other shutter element to partially obstruct its light and constitute a valve limiting the air flow rate in the event of pressure variation in the other direction.
  • the device may include return means exerting their force in the direction opposite to the flow restrictor valve.
  • the elasticity of the valve can constitute these return means.
  • the partition of the device may be a membrane separating the duct into an upstream part and a downstream part, the membrane being pierced with holes for the passage of the air flow in the event of balance between the pressures internal and external to the vehicle, the membrane being, in the event of rapid variation between the pressures internal and external to the vehicle, pressed against the closure element whose receiving face is capable of blocking all the holes in the membrane.
  • the device can in this case comprise a single membrane and at least two sealing elements, one of these sealing elements having a receiving face against which the membrane is pressed when the rapid variation between the internal and external pressures at the vehicle is due to a pressure of said upstream part greater than the pressure of said downstream part, the other closure element having a receiving face against which the membrane is pressed when the rapid variation between the pressures internal and external to the vehicle is due to a pressure of said downstream part greater than the pressure of said upstream part.
  • the obturation elements can then have an asymmetry of shape so as to favor a direction of flow of air in the duct.
  • FIG. 1 represents the general diagram of a ventilation circuit of a train car 1, for example at high speed.
  • This car comprises a suction duct 2 for the outside air arranged between the inlet orifice 3 and the internal ventilation circuit and a discharge duct 4 for the interior air arranged between the internal ventilation circuit and the air outlet orifice 5.
  • the various elements of the internal ventilation circuit (partial air recirculation, heating or air conditioning device, fans, etc.) have no particular influence on the operation of the device according to the invention.
  • the device according to the invention can be used to avoid the effects of an overpressure in one direction, for example the effects due to an increase in pressure external to a vehicle.
  • the most elaborate system will be described, that is, one capable of combating the effects of overpressures in both directions.
  • FIG. 2 there is shown a device according to the invention which can for example be arranged in a duct for renewing the air inside a rail vehicle.
  • the conduit comprises two parts 10 and 11 placed end to end along their faces 12 and 13.
  • the device comprises two closure elements 14 and 15 framing a flexible blade 16.
  • the elements 14 and 15 are provided to fit in the conduit . They are fixed to the duct, for example by screwing, with the interposition of a peripheral seal.
  • the blade 16 is held by upper supports 17 and lower 18. All of the parts 14, 15, 17 and 18 can be made integral by bolting. After insertion of the device into the conduit, the two parts 10 and 11 are joined by fixing members, not shown.
  • the closure elements 14 and 15 are symmetrical. They each have a receiving face 21, 22 into which a light 23, 24 opens. The reception faces are arranged opposite one another and the lights 23 and 24 allow the air flow between the parts 10 and 11 of the duct.
  • the blade 16 has a narrower width than the width of the conduit. The flow can therefore be done by lateral bypass of the blade. The width of the blade 16 is however greater than the width of the openings 23 and 24.
  • the parts 14, 15, 17 and 18 can be metallic, for example aluminum.
  • the blade 16 can for example be made of special steel, aluminum or synthetic material.
  • the blade 16 is a rectangular plate located near the receiving faces 21 and 22. It is articulated by its upper and lower sides to the supports 17 and 18. The articulation can be carried out by a ball joint system 25 and 26 (see figure 3A) or by simply embedding in a slot (see Figure 3B).
  • the air flow takes place by lateral bypass of the plate 16.
  • the plate In the event of a sudden variation between these pressures, the plate is subjected to a force tending to press it down. against either of the receiving faces. If the plate is hinged in an elastic manner, it can completely block off the light from the receiving face against which it is pressed.
  • the pressure difference on either side of the plate generates an air flow whose speed increases, which causes the increase in the aerodynamic drag force of the blade.
  • the drag force causes deformation of the blade. It is this drag that creates the pressure difference on either side of the blade.
  • FIG. 3A shows how this elastic articulation can be produced. It is a detail view on the upper articulation of the blade 16, but the lower articulation can be presented in an identical manner.
  • the upper support 17 has a longitudinal circular groove 27 in which a rod 28 secured to a band 29.
  • FIG. 3B shows a variant in which the blade is embedded in a slot.
  • the strip 29 is connected to the blade 16 by small springs 30 whose stiffness is calculated to obtain, depending on the flexibility of the blade, the application of the blade to one of the receiving faces from a determined level of pressure difference.
  • the elasticity of the blade can constitute the return element thereof.
  • articulation systems can be used to allow the blade to take the shape of the receiving face in the event of overpressure.
  • the blade can for example be articulated in the upper part by a ball joint system and be simply guided in the lower part by a slide made in part 18.
  • the receiving faces 21 and 22 of the parts 14 and 15 are curved and concave parts receiving the curved blade in the event of significant overpressure.
  • the blade When the blade is pressed against a receiving face, it completely blocks the passage of air.
  • the device acts as a flow limiter. Indeed, in this case the overpressure air entering the device finds a decreasing access section.
  • the device of the invention can be placed in all the conduits connecting the interior volume of the vehicle to the exterior.
  • it insulates the interior of the exterior of the vehicle whether the overpressurized air is internal or external to the vehicle.
  • the restoration of the balance between internal and external pressures is done in a controlled manner by a leak orifice.
  • This leak orifice may be formed in part by the vehicle leaks.
  • the air flow exchanged between the interior and the exterior of the vehicle is thus forced to take place over a sufficiently long period that the pressure variations (overpressure or depression) are not a problem for vehicle passengers.
  • the device as described in the figure can be used symmetrically or asymmetrically depending on the distance separating the blade from the receiving faces.
  • the blade is in the rest position (zero flow) equidistant from the two receiving faces. In case of nominal flow, the blade approaches the receiving face located downstream of the air flow.
  • the blade is in the rest position at an unequal distance from the two receiving faces. In the case of nominal flow, it can be located substantially at equal distance from the two receiving faces.
  • the device according to the invention can act as a valve and prevent any air circulation from a certain level of overpressure. It can also act as a flow limiter if the blade cannot completely obstruct a receiving face. This may be due to non-complementary shapes of the receiving face and of the blade or also to the presence of bumps or stops preventing complete closure.
  • the device can be used in one direction as a speed limiter and in the other direction as a closing valve. This is illustrated in Figure 4 where the device shown is mounted in the two parts 35 and 36 of the conduit in the same manner as for Figure 2.
  • the shutter member 57 is identical to those of Figure 2
  • the shutter element 38 has a receiving face 39 of a shape different from the face 40 of the element 37. Lights 41, 42 pass through the elements on either side. 37 and 38 to allow air circulation in the duct.
  • the blade 43 of the device is a rectangular plate, one side of which is fixed in an upper support 44. In the rest position, its lower part rests against a stop 45.
  • the width of the blade 43 is smaller than the width of the elements 37 and 38 to allow normal air flow to the sides.
  • the blade can occupy two extreme positions 46, 47 shown in broken lines. In position 46, the blade does not completely block the light 41 and the device operates as a flow limiter. In position 47, the blade covers the surface 39 and completely blocks the light 42.
  • the free side of the blade 43 can be mounted on a spring so that at nominal flow rate the spring is fully compressed and the blade in abutment as illustrated in FIG. 5 which is a side view of part of the device of the FIG. 4.
  • the stop 45 supports several aligned springs 48 to which is fixed a strip 49 receiving the thrust from the blade 43. The air flow is therefore directed from the element 38 towards the element 37.
  • the springs can be replaced by another force application system and in particular by the effect of gravity.
  • the conduit has a circular section. It comprises two parts 51 and 52 fixed end to end, for example by bolting.
  • the part 52 is fitted inside a part 53 serving as a closure element.
  • This part 53 includes a frustoconical part 54 penetrating in the part 51 and feet 55 allowing the fixing of the closure element on the part 52 of the duct while allowing an air flow.
  • the part 51 of the duct comprises an internal flange 56 on which is fixed a membrane 57 pierced with holes 58.
  • the holes 58 allow the circulation of air in the two parts of the duct (case of FIG. 6).
  • the membrane is pressed against the frustoconical part 54 serving as receiving face (case of FIG. 7) .
  • the holes 58 are distributed in the membrane so as to be able to achieve this objective. There must be no holes at the periphery of the membrane if the device is to serve as a closing valve. If, on the other hand, it is desired to produce a flow limiter, the periphery may include holes making it possible to always have an air flow.
  • the part 53 For the device to operate for overpressures occurring on one side or the other, it suffices to give the part 53 a second frustoconical part directed towards the part 52 and to provide a second membrane.
  • FIGS. 8 and 9 which, by way of example, relate to ducts of circular section.
  • the device of Figure 8 is arranged between two parts 61 and 62 of a conduit.
  • the parts 61 and 62 are for example of axes offset by the interposition of the connecting element 63 which constitutes one of the elements of the device.
  • the parts 61, 62 and the element 63 are joined for example by bolting.
  • the element 63 surrounds closure elements 64, 65, 66 and 67.
  • the internal wall of the element 63 also constitutes a closure element. These elements obturation form a more or less continuous receiving face for the membrane.
  • the shutter elements 65 and 67 are supported by the part 61 by feet, not shown.
  • the shutter elements 64 and 66 are supported by the part 62 by feet, not shown.
  • a pierced membrane 68 is fixed obliquely to the internal wall of the connecting element 63. On assembly it takes the zigzag shape shown in FIG. 8.
  • the device of FIG. 8 operates in the manner of the device of FIGS. 6 and 7.
  • the closure elements 64, 65, 66 and 67 as well as the internal wall of the connection element 63 have receiving faces for the membrane. 68.
  • the membrane 68 tends to press against the receiving faces of the elements 64, 66 and against the lower part of the connecting element 63
  • the membrane 68 tends to press against the receiving faces of the elements 65 and 67 and against the upper part of the connecting element. 63.
  • the shape of the closure elements, the shape of the connecting element as well as the distribution of the holes in the membrane are calculated so that, depending on the desired objective, the device acts as a closing valve or as a limiter. of debt.
  • the device of FIG. 8 is symmetrical, that is to say that it provides the same response for overpressures occurring from part 61 or from part 62.
  • the device of FIG. 9 on the other hand is asymmetrical.
  • the device of Figure 9 is arranged as above, between two parts 71 and 72 of a conduit. It comprises an element 73 ensuring the connection between the parts 71 and 72 and obturation elements 74, 75, 76 and 77 as well as a perforated membrane 78.
  • the essential difference compared to the device of FIG. 8 lies in the shape different existing between elements 74 and 76 on the one hand and elements 75 and 77 on the other hand, as well as between the lower and upper parts of the connecting element 73.
  • Elements 74 and 76 may for example be more thin than the elements 75 and 77 and be terminated by cylinders 81 and 82 which have the effect that, for an air flow going from the part 71 towards the part 72, it is more difficult to stick the membrane 78 on the faces receiving elements 74 and 76. This makes it possible to favor the flow in one direction rather than the other.
  • the entrance to the part 72 can be completed by a pierced wall 85 which adjusts on the closure elements 74 and 76. This makes it possible to constitute a better receiving face for the membrane.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Air-Flow Control Members (AREA)
  • Air-Conditioning For Vehicles (AREA)
EP94400777A 1993-04-16 1994-04-11 Vorrichtung zum Vermeiden oder Begrenzen von plötzlichen Druckänderungen in Fahrzeugen, insbesondere in Landfahrzeugen Withdrawn EP0620392A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9304522A FR2704040B1 (fr) 1993-04-16 1993-04-16 Dispositif de suppression ou de limitation des variations brutales de pression dans les véhicules, en particulier dans les véhicules terrestres.
FR9304522 1993-04-16

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EP0620392A1 true EP0620392A1 (de) 1994-10-19

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EP94400777A Withdrawn EP0620392A1 (de) 1993-04-16 1994-04-11 Vorrichtung zum Vermeiden oder Begrenzen von plötzlichen Druckänderungen in Fahrzeugen, insbesondere in Landfahrzeugen

Country Status (4)

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EP (1) EP0620392A1 (de)
JP (1) JPH06298088A (de)
CA (1) CA2121426A1 (de)
FR (1) FR2704040B1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023194246A1 (de) * 2022-04-08 2023-10-12 Siemens Mobility GmbH Fahrzeug zur personenbeförderung mit druckschutzeinrichtung

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE371783C (de) * 1923-03-22 Siller & Rodenkirchen G M B H Ventil fuer Pumpen, Kompressoren u. dgl. nach Patent 369399 mit Blattfederverschluss und der Form der Blattfeder angepasster Ventilkammer
US3260274A (en) * 1961-12-15 1966-07-12 Robertshaw Controls Co Selector valve
US3324877A (en) * 1963-12-30 1967-06-13 Gen Electric Check valve
CH492910A (fr) * 1968-05-02 1970-06-30 Battelle Memorial Inst Interna Soupape bistable
SU1337597A1 (ru) * 1985-12-26 1987-09-15 Предприятие П/Я М-5671 Обратный клапан
EP0315108A2 (de) * 1987-11-02 1989-05-10 Hitachi, Ltd. Lüftungsausrüstung für rollendes Material
EP0498554A1 (de) * 1991-02-08 1992-08-12 Hitachi, Ltd. Methoden und Gerät zur Belüftung von Reisezugwagen
EP0523752A1 (de) * 1987-11-02 1993-01-20 Hitachi, Ltd. Lüftungseinrichtung für Schienenfahrzeuge

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE371783C (de) * 1923-03-22 Siller & Rodenkirchen G M B H Ventil fuer Pumpen, Kompressoren u. dgl. nach Patent 369399 mit Blattfederverschluss und der Form der Blattfeder angepasster Ventilkammer
US3260274A (en) * 1961-12-15 1966-07-12 Robertshaw Controls Co Selector valve
US3324877A (en) * 1963-12-30 1967-06-13 Gen Electric Check valve
CH492910A (fr) * 1968-05-02 1970-06-30 Battelle Memorial Inst Interna Soupape bistable
SU1337597A1 (ru) * 1985-12-26 1987-09-15 Предприятие П/Я М-5671 Обратный клапан
EP0315108A2 (de) * 1987-11-02 1989-05-10 Hitachi, Ltd. Lüftungsausrüstung für rollendes Material
EP0523752A1 (de) * 1987-11-02 1993-01-20 Hitachi, Ltd. Lüftungseinrichtung für Schienenfahrzeuge
EP0498554A1 (de) * 1991-02-08 1992-08-12 Hitachi, Ltd. Methoden und Gerät zur Belüftung von Reisezugwagen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SOVIET INVENTIONS ILLUSTRATED Section PQ Week 8816, Derwent World Patents Index; Class Q66, AN 88-110493 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023194246A1 (de) * 2022-04-08 2023-10-12 Siemens Mobility GmbH Fahrzeug zur personenbeförderung mit druckschutzeinrichtung

Also Published As

Publication number Publication date
CA2121426A1 (fr) 1994-10-17
FR2704040B1 (fr) 1995-05-19
FR2704040A1 (fr) 1994-10-21
JPH06298088A (ja) 1994-10-25

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