Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B61—RAILWAYS
  • B61F—RAIL VEHICLE SUSPENSIONS, e.g. UNDERFRAMES, BOGIES OR ARRANGEMENTS OF WHEEL AXLES; RAIL VEHICLES FOR USE ON TRACKS OF DIFFERENT WIDTH; PREVENTING DERAILING OF RAIL VEHICLES; WHEEL GUARDS, OBSTRUCTION REMOVERS OR THE LIKE FOR RAIL VEHICLES
  • B61F5/00—Constructional details of bogies; Connections between bogies and vehicle underframes; Arrangements or devices for adjusting or allowing self-adjustment of wheel axles or bogies when rounding curves
  • B61F5/02—Arrangements permitting limited transverse relative movements between vehicle underframe or bolster and bogie; Connections between underframes and bogies
  • B61F5/14—Side bearings

Definitions

• the present invention relates to a railway carriage provided with pneumatic secondary suspensions.
• a railway carriage comprises a body connected by way of secondary suspensions, to bogies provided with wheels.
• the secondary suspensions dampen the vibration of the body to allow a comfortable journey for carriage passengers.
• the secondary suspensions are of hydro-pneumatic or pneumatic type and are associated with a control system that is adapted to adjust the height of the body in function of the load, i.e. the passengers.
• a primary suspension is provided between the axles of the wheels and the frame of each bogie.
• the primary suspension is generally defined by rubber elements or steel springs.
• the pneumatic secondary suspension comprises two air springs 1, one for the right side and the other for the left side of the bogie, supplied by the respective pressurized air streams, which are adjusted by respective control valves 2.
• the control valves 2 are fixed with respect to the body 3 (partially shown) and are operated by levers or other mechanical control devices 4, which are mounted on the right side and on the left side of the carriage, are connected to the frame of the bogie 5, and vary the opening of the respective control valves 2 in response to the vertical distance of the control valves 2, and therefore of the body 3 , with respect to the bogie 5.
• the control system further comprises:
• valve (not shown) communicating with the two air springs and sending a pneumatic signal, indicative of the average pressure of the springs themselves, towards the braking system of the carriage.
• the aim of the present invention is to provide a railway carriage, which allows to simply and economically solve the problems outlined above.
• a railway carriage as defined in claim 1.
• Figure 1 illustrates, partially and in perspective, a railway carriage of the known art
• FIG. 2 is a pneumatic diagram illustrating a preferred embodiment of the railway carriage according to the present invention.
• FIG. 2 with 10 is indicated, as a whole, a railway- carriage (schematically and partially illustrated) , comprising a body 12 and a plurality of bogies, only one of which is illustrated and indicated by reference number 13.
• the bogie 13 comprises a frame and two pairs of wheels, which are coupled to the frame by way of a pneumatic primary suspension (not shown) .
• the body 12 is connected to the frame of the bogie 13 by way of two air springs 16, of a known type, mounted one on the right side and one on the left side of the bogie 13, and defining part of a pneumatic secondary suspension 17.
• the suspension 17 is supplied with pressurized air from a pneumatic line 18, which also supplies the brakes (not shown) of the bogies 13.
• the suspension 17 comprises, for each air spring 16, a respective tank 19 and a respective solenoid valve 20, of proportional type.
• Each tank 19 is connected parallel to the corresponding air spring 16 and to a relative pneumatic attachment 21, known as "test point", throughout a pneumatic line 22. Due to the tanks 19, in all operating conditions the actual frequency of the air springs 19 is that according to project, i.e. in this case less than 1.5 Hz. Due to attachments 21, however, it is possible to connect a pressure gauge to lines 22 in order to measure the pressure within air springs 16.
• the solenoids of the valves 20 are connected to an electronic control unit 30 by way of respective lines 29 for receiving electrical control signals.
• Each of the valves 20 comprises a three-way pneumatic connection, indicated by reference letters V, L and E.
• the way V is connected to line 18 by way of a pneumatic line 31, the way L is connected to the line 22 and, therefore, adapted for supplying pressurized air to the corresponding air spring 16, and the way E is connected to the external environment so as to define a discharge. Under resting conditions, i.e.
• valves 20 in absence of the electrical control signals and, therefore, with the solenoid de-energized, the moving elements of valves 20 are arranged in a central position, so as to block the ways V, L and E and, therefore, maintaining constant stiffness of air springs 16, with equal load (i.e. passengers).
• the moving parts of the valves 20 are moved in one direction or another with respect to the central position, for supplying the lines 22 and sending pressurized air in the air springs 16 or, respectively, for discharging the lines 22.
• the valves 20 adjust the flow of pressurized air that enters /exits with respect to the air springs 6 and therefore adjusting the height of the left and right sides of the body 12.
• the unit 30 is connected to the following components of the suspension 17 :
• position sensors 32 which are arranged respectively on the sides of the carriage 10 and provide, by way of respective electrical lines 33, signals indicative of the relative position between the frame of the bogie 13 and the body 12 on said sides; for example, position sensors 32 are defined by rotary transducers that detect the height of the air springs 16;
• an electrical control line 34 which transmits, to a braking system and/or a driving system (not shown) , a signal indicative of the average pressure of the air springs 16, and/or the deformation of the springs themselves and/or the load supported by the suspension (deriving from the above mentioned deformation) ;
• valve 20 and the transducers 38 and 36 are integrated into a single unit or body 40, which is mounted in a fixed position on the bogie 13 and has three openings or pneumatic connections, corresponding to the ways L, E and V described above, at least one electrical input for the line 29, and two electrical outputs on the lines 37 and 39.
• the unit 30 is configured with appropriate control strategies for performing the following tasks :
• a maximum threshold e.g. 2.5 bar
• the carriage 10 is provided with additional sensors for measuring the relative position between the body 12 (or the doors) and the platform.
• the unit 30 may have a memory containing data concerning the relative position between the platform and the rails at the stop stations along the itinerary, or it can receive said data by way of a wireless transmission system from stop station control units, so as to adjust the height of the body 12 on the basis of the comparison between the measurements of the position sensors 32 and said data.
• avoiding additional sensors requires a series of preliminary experimental measurements in each stop station, for determining which data to store or transmit to the unit 30 .
• the unit 30 When pressurized air is supplied to the air springs 16 , the unit 30 sets the electrical control signals for adjusting the opening degree of the moving parts of valves 20 and, therefore, the air passage section of the valves 20 , in response to the pressure difference between lines 22 and 31 , on the basis of measurements of the transducers 36 and 38 . In this way, the unit 30 finely adjusts the inlet air flow flowing to the air springs 16 and therefore the inflation time . From the foregoing it is evident that the suspension 17 has a very low number of valves, i.e. only the two valves 20 , which, under the control of unit 30 , are able to perform different tasks.
• the unit 30 runs and controls in a closed loop functions that are normally performed by at least four separate valves in the pneumatic secondary suspension of the known art .
• the reduction of the number of valves to be installed implies a simplification of lines of the entire pneumatic system and a simplification of its maintenance.
• the suspension 17 is without mechanical control devices, resulting in reduced size and greater freedom in designing the layout of the suspension components. Thanks to the active type suspension 17, with respect to the secondary pneumatic suspension of the known art in which the valves are operated by mechanical control devices, it is possible to automatically adjust the height of the body 12 with respect to the platform of the stop stations to allow more comfort to passengers boarding/exiting, particularly passengers with disabilities. In addition, it is possible to automatically compensate for the deformation under load of the primary suspension in order to always maintain a substantially equal height of the body 12 from the ground.
• the attachments 21 also allow to verify if the signals of the transducers 36 are correct; and the transducers 38 allow for decisive and fine control in adjusting the air flow flowing through the valves 20.
• the transducers 38 may be absent, or only one could be provided, separated from the valves 20. Even the transducers 36 may be separated from the valves 20, instead of being part of the same unit 40.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Vehicle Body Suspensions (AREA)
• Lock And Its Accessories (AREA)
• Control Of Vehicles With Linear Motors And Vehicles That Are Magnetically Levitated (AREA)
• Train Traffic Observation, Control, And Security (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=43739130

Family Applications (1)

Country Status (6)

Cited By (2)

Citations (2)

• 2010
  • 2010-09-03 IT ITTO2010A000734A patent/IT1402175B1/it active
• 2011
  • 2011-09-05 PL PL11773850T patent/PL2611668T3/pl unknown
  • 2011-09-05 WO PCT/IB2011/053871 patent/WO2012029054A1/en active Application Filing
  • 2011-09-05 ES ES11773850.0T patent/ES2539137T3/es active Active
  • 2011-09-05 EP EP11773850.0A patent/EP2611668B1/en active Active
• 2015
  • 2015-06-19 HR HRP20150665TT patent/HRP20150665T1/hr unknown

Patent Citations (2)

Also Published As

Similar Documents

Legal Events