Actuator for controlling a wheelset of a rail vehicle
10974741 · 2021-04-13
Assignee
Inventors
Cpc classification
International classification
Abstract
The present disclosure relates to an actuator for controlling a wheelset of a rail vehicle comprising: an axle casing for fastening to an undercarriage or to a wheelset bearing housing of the rail vehicle; a synchronized cylinder that is provided in the axle casing and that comprises a piston surface that has a piston rod passing through the axle casing at each of its two areal sides; and a housing that is movable in accordance with a movement of the synchronized cylinder with respect to the axle casing, wherein a piston spring element that connects a respective piston rod to the housing is arranged at the end of the respective piston rod remote from the piston surface.
Claims
1. An actuator for controlling a wheelset of a rail vehicle comprising: an axle casing for fastening to an undercarriage or to a wheelset bearing housing of the rail vehicle; a synchronized cylinder that is provided in the axle casing and that comprises a piston surface that has a piston rod passing through the axle casing at each of its two areal sides; and a housing that is movable in accordance with a movement of the synchronized cylinder with respect to the axle casing, wherein a piston spring element that connects a respective piston rod to the housing is arranged at the end of the respective piston rod remote from the piston surface, and wherein the piston spring element arranged at the respective piston rod is a rubber laminated spring that is of rectangular or cylindrical shape and/or whose layers are stacked in parallel with the longitudinal direction of the respective piston rod.
2. The actuator in accordance with claim 1, wherein the axle casing has a substantially elongate shape and the synchronized cylinder is arranged at the longitudinal center of the axle casing.
3. The actuator in accordance with claim 2, wherein the two piston rods are oriented perpendicular to the longitudinal direction of the axle casing.
4. The actuator in accordance with claim 1, further comprising an axle casing spring element that is arranged directly between the axle casing and the housing, wherein a main spring direction of the axle casing spring element is oriented in parallel with a longitudinal direction of the axle casing; and wherein the axle casing spring elements are rubber laminated springs whose layers are stacked in parallel with the longitudinal direction of the axle casing.
5. The actuator in accordance with claim 4, wherein a pair of axle casing spring elements is provided at one side of the plane defined by the longitudinal direction of the piston rod and by a longitudinal direction of the axle casing and is arranged such that it cushions a movement of the housing directed in the longitudinal direction of the axle casing with respect to the axle casing.
6. The actuator in accordance with claim 1, further comprising a sliding element for the sliding support of the housing at the axle casing in a plane defined by the piston rod and by a longitudinal direction of the axle casing, wherein a first sliding element is provided at a first side of the plane defined by the piston rod and by a longitudinal direction of the axle casing and a second sliding element is provided at a second side.
7. The actuator in accordance with claim 6, wherein the sliding element has a planar sliding surface to permit a movement in the longitudinal direction of the piston rod and has an element in the shape of a segment of a circle to permit a rotation about the normal direction with respect to the plane defined by the longitudinal direction of the piston rod and by a longitudinal direction of the axle casing.
8. The actuator in accordance with claim 1, further comprising a path sensor that cooperates with a piston rod and the axle casing to determine the offset of the synchronized cylinder from a zero position.
9. The actuator in accordance with claim 1, further comprising a valve that connects the two chambers of the synchronized cylinder to one another and a valve control that is adapted to achieve an adjustment of the synchronized cylinder in that the flow of a hydraulic fluid from the one chamber into the other chamber is permitted in a direction corresponding to the desired adjustment movement, with the actuator not making use of or having a hydraulic unit for an active actuation of the synchronized cylinder.
10. The actuator in accordance with claim 9, wherein the valve of the actuator is coupled to a further synchronized cylinder of a leading or trailing actuator; wherein the valve control is adapted to utilize the hydraulic fluid flow of the trailing actuator for the adjustment of the leading actuator; and wherein neither the trailing nor the leading actuator makes use of or has a hydraulic unit for an active actuation of the synchronized cylinder.
11. The actuator in accordance with claim 1, further comprising a hydraulic unit for actuating the synchronized cylinder, wherein the former is arranged at the undercarriage and/or at the front side at a longitudinal end of the axle casing.
12. The actuator in accordance with claim 1, further comprising an energy generation unit for supplying the actuator with energy that generates an energy while utilizing pressure changes in the synchronized cylinder or hydraulic fluid flows of the synchronized cylinder based thereon that occur on a travel of the rail vehicle.
13. The actuator in accordance with claim 1, further comprising sensors that enable a higher quality control and/or diagnosis of the undercarriage and/or of the track state.
14. The actuator in accordance with claim 1, further comprising a visual status display that can display the different status.
15. The actuator in accordance with claim 1, further comprising an interface, USB or WiFi, that can communicate with a mobile device and enables an online diagnosis.
16. The undercarriage of a rail vehicle having an actuator in accordance with claim 1, wherein the axle casing of the actuator is rigidly connected to the undercarriage; and the housing of the actuator is pressed into an axle guide, is connected to a wheelset bearing housing, or is integrated in a wheelset bearing housing.
17. The undercarriage in accordance with claim 16, wherein one actuator is provided per wheelset; and/or wherein the actuator has a high inherent damping in a non-actuated state that enables an autonomous alignment of the wheelset while traveling on a straight rail stretch.
18. The method of operating an actuator that is adapted to control a wheelset of a rail vehicle, in particular to operate such an actuator in accordance with claim 1, wherein, in the method: the adjustment of the actuator is carried out for pivoting the wheelset with respect to an undercarriage on the basis of a displacement angle of the undercarriage with respect to a car body supported by the undercarriage; and the adjustment of the actuator based on the displacement angle takes place after exceeding a first threshold value of the displacement angle, wherein the adjustment of the actuator takes place proportionally to the displacement angle.
19. The method in accordance with claim 18, wherein the actuator for pivoting the wheelset is connected to a further leading or trailing actuator of the rail vehicle; and wherein the trailing actuator is adjusted on the basis of the adjustment movements of the leading actuator to eliminate system-induced delays in the adjustment of the trailing actuator.
Description
BRIEF DESCRIPTION OF THE FIGURES
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DETAILED DESCRIPTION
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(13) The piston surface 4 of the cylinder 3 has a piston rod 5 that passes through the axle casing 2 at each of its two areal sides. The piston rods 5 are oriented in the X direction here. A piston rod spring element 7 that is connected to a housing 6 of the actuator 1 is arranged at the ends of the respective piston rod 5 arranged outside the axle casing 2.
(14) The cylinder chambers 31, 32 formed in the axle casings 2 are here separated from one another by the piston surface 4 of the synchronized cylinder 3. A displacement of the cylinder 3 in the X direction, that is perpendicular to the longitudinal direction of the axle casing (Y direction), is possible with the aid of feed lines, not shown, into the cylinder chambers 31, 32 or corresponding drain lines from the cylinder chambers 31, 32. Not only the piston rod 5 and the piston rod spring element 7 arranged at a front side of the piston rod 5 are thereby displaced, but also the housing 6 connected to the piston rod spring element 7. Said housing slides over a sliding element 9 in the X direction along the axle casing 2.
(15) In this respect, a plurality of sliding elements 9 can be provided that are arranged offset from one another in the vertical direction (Z direction). Each sliding element 9 can here have an element 92 shaped as a segment of a circle and a sliding plate 91 so that a rotation of the housing 6 about the Z axis (vertical direction) is also possible.
(16) The piston rod spring element 7 is a rubber laminated spring in the representation that is adapted to replicate or to determine the longitudinal stiffness of the wheelset guide. It can be of cylindrical shape and is installed with a preload via a bearing sleeve. The piston spring element 7 furthermore has a low shear resistance so that the wheelset bearing housing can perform the movements about the X axis and the transverse movements without any substantial load on the piston rod 5 and its guides through the axle casing 2.
(17) Accordingly, not only the associated piston rod 5 and the piston spring element 7 move by the movement of the synchronized cylinder 3 in the X direction, but also the housing 6 arranged at the piston spring element 7. The sliding element 9 that can be provided in the Z direction both at an upper side and at a lower side of the axle casing 2 here supports the freedom of movement of the housing in the X direction and for a rotation about the Z axis.
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(19) It can be recognized that sections of the axle casing 2 that are provided for a fastening to an undercarriage frame project out of the housing 6 at both sides. The relative movement of the actuator 1 with respect to the undercarriage that is utilized for a pivoting of the wheelset with respect to the undercarriage results from the fixed linking of the axle casing 2 to an undercarriage and from the possibility of the cylinder movement with respect to the axle casing 2. The cylinder 3 and the housing 6 are here moved perpendicular to the Y axis (width direction) along the X axis (longitudinal direction). In addition to the components already named in
(20) An axle casing spring element 8 can furthermore be recognized that provides a cushioning between the housing 6 and the axle casing 2. The main spring direction of this axle casing spring element 8 is here in parallel with the longitudinal direction (Y direction) of the axle casing 2 and thus substantially serves the replication or determination of the transverse stiffness of the wheelset guide. The axle casing spring element 8 can here likewise be designed as a rubber laminated spring that is soft in the X direction to enable high adjustment paths with a low actuator force. The axle casing spring element 8 can here be provided pair-wise offset in the Y direction between the axle casing 2 and the housing 6. Provision can also be made that the axle casing spring elements 8 are attached pairwise at the top or at the bottom (in the Z direction). The number and the arrangements positions of the axle casing spring elements 8 are provided in dependence on the demand of the actuator.
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(22) The synchronized cylinder 3 whose piston rods 5 can now be moved out of the plane of the paper or into the plane of the paper is substantially oriented perpendicular to the longitudinal direction of the axle casing 2. The axle casing 2 has a middle section that has a flange-like protrusion to form contact surfaces for the plurality of axle casing spring elements 8. The sliding elements 9 for a sliding support of the housing at the axle casing 2 are furthermore also provided at the middle section. It can be recognized in this view that the housing 6 does not have any direct linking point to the axle casing 2 so that it is displaceably supported with respect thereto. The position of the housing 6 here depends on the position of the synchronized cylinder 3 with respect to the axle casing 2. To determine the position, a position encoder 10 is provided that cooperates with a piston rod 5 of the synchronized cylinder 3 so that the current position of the housing 6 or of the piston of the cylinder 3 can be determined.
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(24) A state display is marked by reference numeral 14 that can be a color LED lamp in an embodiment. It is attached to the housing of the actuator 1 in an easily visible manner and enables a state recognition with the aid of a visual control. Provision can be made here that the recognition concept of the state is designed as follows:
(25) When working properly the lamp 14 lights up continuously as green, with the color changing to red on a malfunction. If a differentiated diagnosis should be able to be displayed, further colors such as orange, yellow, etc. can be used or a non-lighting up can be used as a further status. A power failure, a sensor failure, a pump line can be considered as examples for further status.
(26) A wirelessly working diagnosis stick 15 can furthermore also cooperate with an actuator 1. As a USB dongle having WiFi data transmission, it can transmit information to a mobile end device 93. It is advantageous that this can also take place during a trip of the rail vehicle so that the measurement parameters of the respective undercarriage can be recorded over a known distance and can be compared with corresponding data of a correctly operating system. It is of advantage if the transmission of the data takes place to the respective car or another car of the rail vehicle or to the driver's cab. All the data of the system that are present such as sensor data, valve data, data on the motor and on the pump, the power supply and a status display can be recorded here. The system data can then be recorded over the time or over the distance with the aid of diagnostic software and can be compared with measurement data of the same distance or of the same path section saved earlier. It is possible to recognize required corrective interventions and to plan them at an early time with the aid of this interface.
(27) It can be recognized that an energy supply 16 is connected to the hydraulic unit 13 and to the valve control 12 to supply these units with energy.
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(29) The arc radius of a curve travel is accordingly determined with the aid of the measurement apparatus 20 that is, for example, provided by position encoders lengthways in or at the anti-rolling device or also separately therefrom.
(30) The control of the wheelsets 50 then takes place via the electrohydraulic actuator 1, with a respective one actuator 1 being provided per wheelset 50. They may be arranged with point symmetry with respect to one another, with the actuator 1 being arranged at the end remote from the drive of the shaft of the wheelset 50. With one actuator 1 per wheelset 50, the former has to exert larger adjustment distances, but the number of components and the costs associated therewith drop considerably. Such an arrangement furthermore provides the advantage that the wheelset 50 is unambiguously positioned in the longitudinal direction and considerably smaller movements arise on the coupling with driven wheelsets.
(31) The actuator 1 may also have a high inherent damping in the passive or non-actuated state since then the wheelset 50 can autonomously align itself ideally when traveling straight ahead and the effectively active longitudinal stiffness of the wheelset guide remains high and ensures a stable handling.
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(33) The actuation of the actuator 1 may take place via a 4/3 way valve 11 that is actuated accordingly via the difference between the desired path and the actual path.
(34) Provision can be made in accordance with the present disclosure here that the control also makes use of further criteria in further cases. Possible further criteria are given in the following in a list: radii, dependently degressive, progressive, step-wise, with any desired transfer functions being conceivable; travel speed or transverse acceleration; traction force that is determined by the measurement of the longitudinal movement between the car body 110 and the undercarriage 100; the actuator force itself that is determined by a pressure measurement in the actuator 1, with this taking account of the quality of the contact geometry between the wheel and the rail; an individual control of the wheelsets, leading or trailing; and a control in the higher frequency range to stabilize the undercarriage (practically at level phase to the sine movement) so that the use of an anti-rolling device can be dispensed with.
(35) Provision can furthermore be made that the hydraulic unit 13 that comprises pumps and a motor is activated as needed. On exceeding a second threshold value of the desired/actual position difference, the pump can be activated and the energy consumption of the actuator can thus be considerably reduced. This means that the pump may be switched on with track conditions having a poor contact geometry, whereas the wheelset 50 brings itself into the correct position without additional force with an acceptable contact geometry since this is also possible with passively activated valves without making use of the hydraulic unit 13.
(36) Provision can furthermore be made that the actuator systems of two or more undercarriages 100 are connected to utilize the information of a leading undercarriage 100. It is thus possible to eliminate delays of the system on the start-up of the pumps of the hydraulic unit for the trailing undercarriages and to exit them in good time. It is thereby also possible to optimize control methods for a running through transitional curves or for track switches.
(37) In an embodiment, the actuator is controlled autonomously from each undercarriage. An energy supply is provided, whereas the data detection, data processing and the actuation itself take place within an undercarriage.
(38) The actuator 1 in the wheelset guide is here integrated in an axle guide bearing or a support bearing. A motor, a pump (both at reference numerals 13), valves 11, path sensors and pressure sensors 91, and a control unit 92 are provided to control the actuator 1 in
(39) The control of the actuator 1 is additionally failsafe in design since the system acts as a stiff wheelset guide with high inherent damping on a failure of the electronics, the sensor system, the power supply, the pump and/or the motor. This means that the undercarriage acts like a classical undercarriage without a wheel set control or with a very slowly acting control.
(40) On a leak and the loss of the longitudinal stiffness, a bumpy running of the undercarriage is adopted that can result in unstable running. The residual damping and residual stiffness in the system, however, prevent an exceeding of safety-relevant limit values of the wheel-rail forces.
(41) Provision can furthermore be made in accordance with an embodiment of the present disclosure that the energy supply is autonomous. An energy generation unit is provided for this purpose that generates its energy using the pressure changes in the synchronized cylinder. For example, a hydraulic fluid pressed out of the cylinder can also be used here to generate energy. The pressures in the cylinder also change continuously while traveling straight ahead so that a passively connected actuator can also be used as the energy source. The power supply of the electronics, of the sensor system, of the valves, and also of the pump can be provided with this energy. The energy generation can here be maximized by a direct actuation of the valves in different travel states.
(42) One embodiment of actuator 1 incorporates such an autonomous energy supply. This concept can also be used when a particularly low energy control state is desired and is not restricted to an autonomous energy supply.
(43) In this respect, each actuator 1 is individually actuated in that the valves each permit the oil flow in the desired direction toward a position of the actuator to be adopted. If the contact geometry between the wheel and the track is sufficient, a wheelset can also be ideally adopted due to this control. If the quality of the contact geometry is, however, not sufficient to reach an autonomous adjustment of the actuator into the desired position, the two cylinders of the leading and trailing wheelsets may be coupled mutually via hydraulic lines and additional valves so that the flow of the hydraulic fluid of the trailing wheelset can be used as required to control the leading wheel set.
(44) This embodiment is in particular of interest in the retrofitting of older vehicles that do not permit the installation of an energy supply due to a lack of available space. The controllable actuator thus does not have any hydraulic unit that comprises a motor and pump, but rather valves between the individual chambers of the synchronized cylinder. It is thus possible to have the cylinders generate forces indirectly or passively. This is done, for example, by opening a valve so that a flow between the chambers is permitted when a force is transferred by the rail to the wheelset that effects an actuation of the actuator in the desired direction. The control of the valves can here likewise take place in accordance with different criteria. They can, for example, be the arc radius of a rail curve, traction force, the radial position of the two wheelsets and/or the cylinder force. It is thus of advantage, for example, to block the throughflow of a hydraulic fluid of the cylinder in both directions to prevent an off-center vehicle running.
(45) Provision can also be made that the cylinder chambers of the leading and trailing actuators are coupled to the mutual control via hydraulic lines. It is thus possible that the leading wheelset is controlled via the movement of the trailing wheelset.
(46) A particularly inexpensive variant of an embodiment in accordance with the present disclosure provides that the actuator does not have a position encoder, but rather a measurement device 20 for determining the displacement angle or the arc radius. A central unit furthermore has electronics, the valves, the generators, an energy store, and a status display. Hydraulic lines also run from the cylinders to the central unit that is in turn connected via a cable connection to the measurement device for determining the displacement angle or the arc radius.
(47) A further function that results on the basis of the actuator in accordance with the present disclosure is the carrying out of a track diagnosis. The present disclosure makes a diagnosis of the track or rail state possible with relatively little effort due to its concept. The information on the arc radius and on the individual position of the wheelsets are available from the concept of the present disclosure. If the system is added to by pressure sensors and a transverse acceleration sensor, all the parameters of interest that describe the track state can be derived. The individual parameters are here determined as shown using the following table 1.
(48) TABLE-US-00001 TABLE 1 Derivation of the parameters defining the track state Parameter Measurement values/Vehicle parameters Arc radius Displacement angle undercarriage 1: Ψ 1 Displacement angle undercarriage 2: Ψ 2 Center pin spacing Start-up angle: αi Displacement angle undercarriage 1: Ψ1 Displacement angle undercarriage 2: Ψ2 Angle of rotation of wheelset i: Ψrsi Track displacement force: ΣYi Actuator force wheelset 1: Fact1 Actuator force wheelset 2: Fact2 Non-compensated transverse acceleration: aq Wheel load Stiffness of the wheelset guide Wheel base Displacement stiffness of the secondary cushioning Single wheel force, Track displacement force transverse: Yij Start angle Wear factor Single wheel force, transverse: Yij Start-up angle: αi Rolling radii difference Arc radius Actuator force wheelset 1: Fact1 Actuator force wheelset 2: Fact2 Wheel load Conicity Actuator force wheelset 1: Fact1 (dynamic) Actuator force wheelset 2: Fact2 (dynamic) Track twisting Path sensors, vertical Track position disturbances, Acceleration sensors, transverse (dynamic) transverse Track position disturbances, Acceleration sensors, vertical (dynamic) vertical Spinning vibrations Accelerations sensors, vertical (dynamic) Acceleration sensors, lengthways (dynamic)
(49) The diagnosis should be provided in around two to three cars of a rail vehicle. It is of aid in this connection if there is a constant connection of the actuators to a processor in the corresponding car or train with access to an evaluation system of the track diagnosis.
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(51) The following claims particularly point out certain combinations and sub-combinations regarded as novel and non-obvious. These claims may refer to “an” element or “a first” element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure.