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
  • B61F5/22—Guiding of the vehicle underframes with respect to the bogies
  • B61F5/24—Means for damping or minimising the canting, skewing, pitching, or plunging movements of the underframes
  • B61F5/245—Means for damping or minimising the canting, skewing, pitching, or plunging movements of the underframes by active damping, i.e. with means to vary the damping characteristics in accordance with track or vehicle induced reactions, especially in high speed mode

Definitions

• the invention relates to a transverse suspension for a rail vehicle and to a method for controlling the position of a rail vehicle body with the features of the preamble of device claim 1 and method claim 8.
• a known cross suspension (EP 0 592 387 A1) is based on these features on a pressure compensation control, in which the active, fluid-supported transverse springs are acted upon by a predetermined setpoint pressure from a pressure source as a function of the transverse travel y of the car body relative to the bogie frame via pressure regulating valves.
• the setpoint pressure is therefore a function of the body deflection in the y direction.
• the car body is not brought into a specific position, in particular is not returned to its central position. Instead, a start on the hard additional or emergency suspension should be avoided when the rail vehicle is traveling normally.
• the characteristic curve of the transverse suspension remains softer than the (rubber) additional suspension despite the pressure increase, so that driving comfort can be increased considerably. Nevertheless, for safety reasons, the additional suspension cannot be entirely dispensed with, since if the pressure control fails, it is the only remaining transverse suspension in addition to the secondary springs.
• a certain disadvantage of this known transverse suspension is its relatively high energy requirement. This arises from the necessity to constantly maintain a certain pressure in the active elements in all driving conditions, that is to say also when driving straight ahead. On the other hand, a constant dynamic pressure reduction must be possible in order to prevent the transverse suspension against the dynamic transverse vibrations of small amplitudes to harden.
• vehicle inward is a certain lateral displacement of the car body compared to the chassis, so that the clearance profile is maintained and the height of the roll pole can be optimized if necessary.
• the roll pole is the axis that is variable in the longitudinal direction of the vehicle and that can change its position in the Z and possibly also the Y direction, about which the car body is currently rotating when it is inclined into an arc.
• the roll pole is shifted upward compared to a conventional rigid pivot-cross spring arrangement. This ensures on the one hand that the clearance profile is maintained on the vehicle side and on the other hand the influence of lateral accelerations from the active inclination control on the well-being of the passengers is minimized.
• the invention is based on the object, based on the prior art discussed at the outset, of specifying an active transverse suspension for rail vehicles, with which dynamic disturbances with low vibration amplitudes can be compensated for by a soft spring characteristic, even in the event of intentional transverse deflections of the car body during stationary bend travel.
• a method for actively controlling the position of a car body by means of such a transverse suspension is also to be specified.
• a second advantage is the possibility of being able to influence the position of the roll pole in a vehicle equipped with active inclination control.
• the energy requirement of the solution according to the invention is lower than in the prior art, because no fluid supply to the drive elements is necessary when driving straight ahead. If fluid is displaced from the drive elements by dynamic transverse vibrations, this does not get into the return, but is buffered in the storage elements.
• FIG. 1 shows a schematic diagram of an active transverse suspension in a rail vehicle.
• Bogie, Figure 2 shows an embodiment of the hydraulic shown in Fig. 1 as a "black box"
• the driver 3 can lie as a pivot in the vertical axis of the pivoting movements of the bogie.
• the drives 5 and 6 are designed as horizontal, double-acting differential lifting cylinders, each with two working chambers and articulated on the cross member 2 so that the Compression of the car body in the secondary suspension and the turning out of the chassis when traveling through bends are not hindered.
• Your working chambers are cross-connected to each other by lines 7 and 8 and are thus connected in pairs to two separate system branches A, B.
• the total effective areas of the lifting cylinders are the same in both directions of movement.
• Each of the two system branches A and B communicates - via a switchable or proportionally controllable valve V1 or V2 - with a hydropneumatic storage element 9 or
• the latter are preloaded on the air side by automatically keeping the hydraulic system pressure above a minimum level.
• the air volumes of the storage elements represent a relatively soft transverse suspension on which the body is supported by the hydraulic system. Cross components from the secondary suspension can also be added.
• the drive device can also work with only one double-acting cylinder instead of the two double-acting cylinders 5 and 6, the two working chambers of which are then each connected to one of the system branches A and B, respectively.
• a displacement sensor 11 is also provided on the piston rod 4, which detects any transverse movement of the driver 3 or the piston rod 4a and / or 4b (ie in the Y direction if the direction of travel is the X and Height in the Z direction) is converted into a voltage signal U.
• the encoder 11, which is drawn out here for the sake of clarity, is preferably integrated into the hydraulic drive. Its electrical movement or position signal is fed to a controller 12 as an output or actual variable for the transverse displacement of the car body.
• the controller output signal in turn reaches a hydraulic control block 13 equipped with various valves (FIG. 2). This is hydraulically connected between lines 7 and 8 and a high-pressure pump 14 together with a return line 15 and hydraulic reservoir 16.
• the pump is e.g. B. designed for a delivery pressure of 210 bar.
• the controller 12 is provided for actively influencing the force-neutral central position of the transverse suspension, as will be discussed in more detail later. If required, it can also have further inputs for pressure-analog signals with which the hydraulic system pressure in the system branches A and B is transmitted by suitable pressure sensors (not shown here).
• a further controller 17 can be provided, the output signal of which, of course, via amplifier, has to control the two valves V1 and V2.
• this device can be used to change the hydraulic damping of the piston rod movement in one step or else proportionally by valve actuation, in one step from the rest position shown, in which the valves V1 and V2 have no throttling action or several steps to a greater throttling of the flow between the working chambers of the drives 5 and 6 and the storage elements 7 and 8.
• Valves V1 and V2 are normally always controlled together. In principle, the device could also work with only one of these valves, since the other system branch is positively coupled via the piston rods 4a and 4b.
• the degree of damping is adjusted depending on the driving speed, the vehicle load and the route situation (straight or curved), possibly according to the given track position.
• the input signals of this controller 17 can be their speed dy / dt and acceleration d 2 y / dt 2 , possibly also stored route data or track data read from the route (track radii, track quality).
• control block 13 preferably comprises a proportional control valve 18, the positions of which can be adjusted by the controller 12. It masters the connections between the two system branches A, B on the one hand and the pump connection P and the return connection T on the other.
• the said connections are closed in its non-activated rest position (eg when driving straight ahead). This position is set automatically even if the electronic control fails. If, on the other hand, a system branch is connected to the pump when the control valve is activated, pressure from the other system branch can be reduced towards the return at the same time.
• control valve 18 is followed by a check valve 19 and, in parallel, a pressure-switchable support valve 20 (from the inlet pressure switch; functonally a pressure limiter) with an adjustable switching threshold, the respective check valve hydraulic fluid being almost unhindered by the pump 14 in the downstream system branch can flow in, while the support valve allows a flow from the system branch to the return only above a predetermined pressure level in the system branch.
• This arrangement alone prevents the pressure level in the two system branches from dropping below a permissible minimum value.
• a pressure-maintaining device 21 (switched from the initial pressure; for example a pressure reducing valve) is additionally connected directly between the inlet P and both system branches A, B, via which with the pump running or pending High pressure constantly a minimum overpressure is delivered in both system branches.
• Check valves 22 prevent backflow via this line, which could otherwise be caused by dynamic pressure peaks above the delivery pressure on the system branch.
• the check valves 22 also ensure the separation of the two system branches.
• control block 13 also comprises a short-circuit valve 23 arranged between the two system branches A and B, which is closed in its rest position, but allows a throttled direct pressure compensation between the two system branches in the working position. This valve is activated when driving straight ahead to further reduce the transverse spring stiffness.
• the control follows a predetermined desired mean value y Soll , the wagon body transverse movement y as an input signal or reference variable, which is generated by a setpoint generator (not shown).
• the desired mean value is zero, ie the body should not move out of the centered center position if possible.
• Dynamic transverse vibrations of small amplitudes are absorbed by the secondary springs (not shown) and by the hydropneumatic storage elements 9 and 10 with low spring stiffness and damping according to requirements.
• the desired mean y is dependent on the current transverse acceleration and the clearance profile.
• the latter also restricts the permitted transverse deflection of the car body in addition to the static vehicle outline in order to prevent collisions with objects located near the track or with vehicles in the adjacent track.
• the controller has such a rule should differences between y and y to minimize, beyond a predefined threshold.
• the threshold value must of course be greater than the amplitude of the dynamic transverse vibrations mentioned.
• the feedback of the value y to the controller ensures that the maximum permissible lateral deviation of the car body cannot be exceeded.
• the control works by increasing the hydraulic system pressure in one of the system branches or in one of the two communicating pairs of working chambers. For this purpose, the control valve 18 is switched in the control block 13 so that the High pressure pump 14 can supply the corresponding system branch. If the pressure in the other system branch rises above the switching threshold of the respective pressure regulating valve, this will open towards the return.
• the line 7 is simultaneously connected to the return. Since the body continues to be supported in the transverse direction even after the transverse displacement on the soft storage elements 9 and 10, the effective stiffness of the transverse suspension remains relatively soft, although not as soft as when driving straight ahead due to the increase in the system pressure. If the piston rod is moved to the left, the process is reversed.
• the roll pole height is noticeably increased due to the displacement of the driver toward the outside of the curve that is possible according to the invention. This should also be aimed at so that passengers do not perceive the transverse movements resulting from the active inclination so clearly.
• the roll pole should therefore preferably lie at the level of the passenger seats.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Vehicle Body Suspensions (AREA)
• Body Structure For Vehicles (AREA)
• Vehicle Cleaning, Maintenance, Repair, Refitting, And Outriggers (AREA)
• Train Traffic Observation, Control, And Security (AREA)
• Electric Propulsion And Braking For Vehicles (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=6520313

Family Applications (1)

Country Status (8)

Families Citing this family (7)

Family Cites Families (5)

• 1994
  • 1994-06-10 DE DE4420367A patent/DE4420367C1/de not_active Revoked
• 1995
  • 1995-05-29 ES ES95921774T patent/ES2125019T3/es not_active Expired - Lifetime
  • 1995-05-29 WO PCT/EP1995/002039 patent/WO1995034455A1/fr active IP Right Grant
  • 1995-05-29 DE DE59503858T patent/DE59503858D1/de not_active Expired - Lifetime
  • 1995-05-29 AT AT95921774T patent/ATE171902T1/de active
  • 1995-05-29 EP EP95921774A patent/EP0764104B1/fr not_active Expired - Lifetime
  • 1995-05-29 PL PL95317581A patent/PL317581A1/xx unknown
• 1996
  • 1996-11-06 FI FI964464A patent/FI964464A/fi not_active Application Discontinuation
  • 1996-11-29 NO NO965110A patent/NO307038B1/no not_active IP Right Cessation

Non-Patent Citations (1)

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