AU2018340218A1

AU2018340218A1 - Method for determining an actuating force on the basis of sound emission measurements

Info

Publication number: AU2018340218A1
Application number: AU2018340218A
Authority: AU
Inventors: Michael Schulze
Original assignee: Siemens Mobility GmbH
Current assignee: Siemens Mobility GmbH
Priority date: 2017-09-29
Filing date: 2018-09-07
Publication date: 2020-03-19
Anticipated expiration: 2038-09-07
Also published as: PL3661829T3; EP3661829A1; WO2019063263A1; DE102017217414A1; ES2903446T3; CN111163993B; EP3661829B1; AU2018340218B2; CN111163993A

Abstract

A method for analysing a points mechanism of rail points is disclosed, wherein at least one sensor for measuring sound waves is arranged on an outer housing or in the outer housing of the points mechanism, measurement signals from the at least one sensor are amplified and recorded during actuating operation of the points mechanism, and an actuating force of an actuating force coupling of the points mechanism is determined on the basis of the recorded measurement signals from the at least one sensor. A points mechanism system is also disclosed.

Description

PCT/EP2018/074095 / 2017P13664WO

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Description

Method for determining an actuating force on the basis of

sound emission measurements

The invention relates to a method for analyzing a switch drive

of a rail switch. The invention also relates to a switch drive

system with a measuring system for carrying out a method of

this type and with a switch drive for displacing switch blades

of a rail switch.

For the shifting of switches, manually or electrically

operated switch drives are used as the most important rail

infrastructure elements. The required actuating force acting

on an actuating rod is achieved with the aid of an adjustable

actuating force coupling. Over the lifespan of the switch

drive, which is up to 25 years, the actuating force set at the

manufacturing works can change. The actuating force can

decrease during the lifespan of the switch drive. Since the

actuating force is relevant to the safety of the operation of

the switch and the switch drive, the actuating force must be

monitored and/or checked by measurements.

Previously, the actuating force of switch drives had to be

checked regularly. For this purpose, servicing of a switch

drive must be organized and carried out. A measurement of the

actuating force takes place on location with a measuring

device and a force measurement bolt. Dependent upon the

measurement result, an adjustment of the actuating force

coupling or an exchange of the whole switch drive takes place.

It is an object of the invention to propose a method for

determining an actuating force of a switch drive whereby a

direct intervention in an operation of the switch drive is

avoided.

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The object is achieved with the subject matter of independent

claims 1 and 10. Advantageous embodiments of the invention are

the subject matter of respective dependent subclaims.

According to one aspect of the invention, a method is provided

for analyzing a switch drive of a rail switch. According to

the invention, at least one sensor for measuring sound waves

is provided. The sensor can be arranged on an external housing

or in the external housing of the switch drive. Subsequently,

measurement signals of the at least one sensor are recorded

during an actuating operation of the switch drive. The

measurement signals can be amplified. On the basis of the

recorded measurement signals of the at least one sensor, an

actuating force of an actuating force coupling of the switch

drive is determined.

As a sensor, for example, a piezoelectric sensor which can

measure sound waves and vibrations generated during an

operation of the switch drive can be used. In particular, an

acoustic surface wave sensor can be used as the at least one

sensor. Such sensors can be configured as economical and

robust in relation to external influences, so that they can be

used for deployment in the field of rail vehicles and rail

networks. The vibrations and sound waves generated by the

components of the switch drive can propagate via fastening

elements and the external housing and can be measured there.

In particular, the oscillations of a switch drive motor, the

mechanical actuating path elements (e.g. actuating slider,

ballscrew), the actuating force coupling and shafts and

bearings can be measured. The at least one sensor can be

calibrated on the basis of measurement signals of a defined

number of shifting processes. A calibration can preferably be

dependent upon a defined target actuating force of the

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actuating force coupling and upon components used in the

switch drive.

An inadequately serviced actuating force coupling is tighter

than an optimally functioning actuating force coupling.

Consequently, the switch drive motor must be operated at a

higher rotary speed in order to generate the necessary torque

for the tight actuating force coupling.

The oscillations generated by the switch drive motor are

dependent, according to a known motor running curve of the

switch drive motor, upon its rotary speed. On the basis of the

determined measurement signals of the at least one sensor, a

loading level of the switch drive motor and thus also of the

actuating force coupling can be determined. In particular, by

means of the emitted measurement signals of the at least one

sensor, deviations from a typical actuating operation can be

detected early.

By means of the method, a contact-free testing of a current

actuating force of the actuating force coupling of the switch

drive can be carried out. A manually executed check of the

actuating force coupling which also represents a direct

intervention in the operation of the switch drive can thus be

avoided. Furthermore, by means of the method, reaction

deviations in the determination of the actuating force of the

actuating force coupling can be minimized.

According to an exemplary embodiment of the method, the at

least one sensor is releasably arranged on an outside of the

external housing of the switch drive. By means of the external

fastening of the at least one sensor, no changes to the

external housing and therefore to existing proof of safety

certifications of the switch drive are required. The actuating

force can thus be measured without any design change to the

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existing switch drive. Thus, switch drives already put into

service can also be checked or retrofitted in accordance with

the method according to the invention.

By means of the technically simple fastening of the at least

one sensor on the external housing of the switch drive, an

implementation for any desired electromechanical switch drive

motors with actuating force couplings is possible. For

example, the at least one sensor can be releasably arranged on

the external housing via at least one magnet, a strap or clamp

encompassing the external housing or a clamp connection.

Alternatively or additionally, the at least one sensor can be

temporarily or lastingly glued into the external housing.

According to a further exemplary embodiment of the method,

stored measurement signals of a plurality of shifting

processes of the switch drive are compared with one another

for determining a servicing requirement of the actuating force

coupling. By means of a comparison of a plurality of

measurements carried out at different times by the at least

one sensor, a tendency or a deviation in the actuating

operation can be detected. A deviation in the oscillation

characteristics or sonic characteristics of the actuating

operation can be an indication of a technical defect or a

future technical defect. Thus, causes of possible defects can

be determined and remedied early, whereby costs for a failure

of the switch drive or an exchange of several components are

avoided.

According to a further exemplary embodiment of the method, a

servicing requirement of the actuating force coupling is

determined in the event that a minimum target value of the

determined actuating force is undershot. On the basis of the

measurement signals determined by the at least one sensor and

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a corresponding calibration of the at least one sensor, an

actuating force of the actuating force coupling can be

calculated.

A need for servicing can be signaled if the calculated

actuating force exceeds or undershoots a defined target value.

For example, a servicing need can be signaled when the target

value of the actuating force is undershot by a factor of 1.2.

According to a further exemplary embodiment of the method,

stored measurement signals of a plurality of actuating

operations of the switch drive are used for determining a wear

condition of the actuating force coupling. On the basis of a

plurality of monitored or tested actuating operations of the

switch drive, a tendency with regard to the oscillation

characteristics of the switch drive can be measured. By this

means, independently of the components of the switch drive, an

event-related optimized service can be realized. Servicing

costs can thus be reduced and an availability of the switch

drive can be increased.

According to a further exemplary embodiment of the method,

stored measurement signals of a plurality of shifting

processes of the switch drive are used for generating a

condition prognosis of the actuating force coupling. On the

basis of the measurement signals, models of the switch drive

and of the wearing parts such as, for example, the actuating

force coupling can be generated. By this means, a predictive

condition prognosis can be generated, which enables statements

to be made to a customer or a service provider regarding a

servicing expenditure or a prevailing status. In particular,

thereby, a continuous actuating force monitoring can be

realized.

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According to a further exemplary embodiment of the method, on

the basis of the generated condition prognosis of the

actuating force coupling, a future servicing time point is

determined. On the basis of temporally offset measurement

signals, a trend or a change in the actuating force can be

detected. Therefrom, a time point can be estimated as to when

a servicing of the switch drive can be advantageous or

necessary. Thereby, existing service models can be checked or

adapted by means of fact-based data analysis of the monitored

switch drive.

In particular, the information determined regarding the

monitored switch drive can be combined with further diagnostic

data, for example, from the program Sidis W compact and used

for optimizing existing diagnostic programs. Thereby, a more

precise risk, status and availability assessment of the switch

drives under investigation can take place.

According to a further exemplary embodiment of the method, the

measurement signals of the at least one acoustic sensor are

continuously or temporally discretely recorded. By this means,

a long-term monitoring of switch drives can be realized. On

the basis of the data or information determined from the long

term monitoring, precise performance data of actuating force

couplings can be obtained dependent upon different

environmental influences and operational usage intensities.

This data can be used for a development and for design

improvements to switch drives.

According to a further exemplary embodiment of the method, the

measurement signals of the at least one sensor are stored and

made available on an external server unit. By this means, the

measurement signals determined or the actuating forces

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calculated therefrom from different actuating force couplings

can be gathered centrally and evaluated.

In particular, the at least one sensor can be coupled to an

evaluating electronics system which can transfer the

determined measurement signals directly to the external server

unit. By this means, a locally independent evaluation of the

measurement signals of the at least one sensor can be enabled.

According to a further aspect of the invention, a switch drive

system with a measuring system for carrying out the method

according to the invention and with a switch drive for

displacing at least two switch blades of a rail switch is

provided. The switch drive has a switch drive motor for direct

or indirect driving of an actuating rod connected to at least

one switch blade, via an actuating force coupling.

Furthermore, the switch drive has a drive electronics system

for controlling and regulating the switch drive motor, and

thereby at least the switch drive motor and the actuating

force coupling are arranged in an external housing of the

switch drive. According to the invention, at least one sensor

for measuring sound waves is mountable on the external housing

and is evaluable by a measuring electronics system, wherein on

the basis of measurement signals of the at least one sensor,

an actuating force of the actuating force coupling is

measurable during an actuating operation of the switch drive.

The measuring system can have, in particular, at least one

sensor which is mountable on any desired surface in or on the

switch drive. The at least one sensor is connected to a

measuring electronics system, wherein the measuring

electronics system can at least preamplify and record the

measurement signals of the at least one sensor.

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The measuring electronics system can be connected to a

transmitting and receiving device so that the recorded

measurement signals of the at least one sensor can be

transmitted to an external server unit. Alternatively, the

measuring electronics system can deposit the recorded

measurement signals of the at least one sensor on a storage

medium, for example, a memory card, hard drive or cloud.

The measuring system can be configured as a portable system

for targeted checking of defined switch drives or as a

retrofitting solution for long-term integration into a switch

drive. Herein, the measuring system can be coupled to the

drive electronics system of the switch drive motor so that

measurement signals are recorded specifically only during

actuating operations.

Preferably, the at least one sensor can be arranged on the

external housing. The at least one sensor can be configured as

protected against environmental influences in a sensor housing

so that mounting or arrangement of the at least one sensor on

an outside of the external housing of the switch drive is

possible. As a result, the external housing does not have to

be opened to carry out measurements nor does its actuating

operation have to be interrupted.

By means of the switch drive system, therefore, a measuring

system can be positioned and operated without a direct

intervention in an actuating operation of a switch drive.

The measurement signals can preferably be time-variable

amplitudes of oscillations and sound waves which travel via

fastenings and holders of components in the external housing

of the switch drive to the at least one sensor and can be

registered there.

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According to an exemplary embodiment of the switch drive

system, the at least one sensor is a surface wave sensor. The

at least one sensor can preferably be a sensor based upon the

piezo effect. The oscillations and sound waves arriving at the

at least one sensor can mechanically excite a piezoelectric

substrate of the at least one sensor, whereby the excitation

generates corresponding voltage pulses and can be evaluated.

In particular, the oscillations and sound waves can be

acoustic surface waves which can propagate on material

surfaces.

The above described properties, features and advantages of

this invention as well as the manner and means by which they

are achieved are made clearer and more distinct through the

description of the following greatly simplified schematic

representations of preferred exemplary embodiments. In the

drawings:

FIG 1 is a perspective view of a switch drive system according

to a first exemplary embodiment,

FIG 2 is a schematic flow diagram of a method for analyzing a

switch drive system according to a first exemplary embodiment.

In the drawings, the same design elements each have the same

respective reference numbers.

FIG 1 shows a perspective representation of a switch drive

system 1 according to a first exemplary embodiment. The switch

drive system 1 consists here of a switch drive 2 and a

measuring system 4 arranged on the switch drive 2.

The switch drive 2 has an external housing 6 which is opened

to make the components visible. The switch drive 2 has a

switch drive motor 8. The switch drive motor 8 is an electric

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motor and drives an actuating slider 10 which is connected to

an actuating rod.

The switch drive motor 8 drives the actuating rod 10

indirectly via a transmission (not shown) and an actuating

force coupling 12 mounted on a ballscrew.

By means of the actuating force coupling 12, a defined

actuating force can be applied to the actuating slider 10. The

actuating force coupling 12 can, in particular, prevent damage

to the switch drive motor 8 and the transmission, if the

actuating slider 10 is blocked during a shifting operation.

The switch drive motor 8 is controlled by a drive electronics

system 14 if a signal for carrying out an actuating operation

is received from a control center (operating element in the

switch tower).

According to the exemplary embodiment, the actuating slider

(the actuating rod) 10 is connected to a switch blade 16 and

can deflect (move) the switch blade 16 transversely to a rail

direction S of the rail 18.

The measuring system 4 consists of a sensor 20 and a measuring

electronics system 22. The sensor 20 is an SAW (Surface

Acoustic Wave) sensor 20 and is positioned on an outside

surface of the external housing 6 of the switch drive 2 with

the aid of a magnet (not shown).

The sensor 20 is coupled to the measuring electronics system

22 so that the measurement signals determined by the sensor 20

are recorded by the measuring electronics system 22 and can be

processed.

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FIG 2 shows a schematic flow diagram of a method 30 for

analyzing a switch drive system 2 according to a first

exemplary embodiment.

In a first step 31, the sensor 20 is arranged on or in the

external housing 6 of the switch drive 2.

Subsequently, the at least one sensor 20 is connected 32 to

the measuring electronics system 22.

The measurement signals of the at least one sensor 20 are

received by the measuring electronics system 22 and stored 33

after amplification and filtration.

In a further step, on the basis of the recorded measurement

signals, an actuating force of the actuating force coupling 12

is determined and/or calculated 34. This can be realized, in

particular, by means of a previously performed calibration of

the at least one sensor 20 and the measuring electronics

system 22.

Although the invention has been illustrated and described in

detail based upon the preferred exemplary embodiments, the

invention is not restricted by the examples given and other

variations can be derived therefrom by a person skilled in the

art without departing from the protective scope of the

invention.

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Reference signs

1 Switch drive system

2 Switch drive

4 Measuring system

6 External housing

8 Switch drive motor

10 Actuating slider (actuating rod)

12 Actuating force coupling

14 Drive electronics system

16 Switch blade

18 Rail

20 Sensor

22 Measuring electronics system

30 Method

31 Arrangement of the at least one sensor

32 Connection of the at least one sensor to a measuring electronics system

33 Receiving and storing of measurement signals

34 Determination of an actuating force

S Rail direction

Claims

PCT/EP2018/074095 / 2017P13664WO 13 Claims

1. A method (30) for analyzing a switch drive (2) of a rail

switch, wherein

- at least one sensor (20) for measuring sound waves is

provided,

- measurement signals of the at least one sensor (20) are

recorded (33) during a shifting operation of the switch drive

(2),

- on the basis of the recorded measurement signals of the at

least one sensor (20), an actuating force of an actuating

force coupling (12) of the switch drive (2) is determined

(34).

2. The method as claimed in claim 1, wherein the at least one

sensor (20) is releasably arranged (31) on an outside of the

external housing (6) of the switch drive (2).

3. The method as claimed in claim 1 or 2, wherein stored

measurement signals of a plurality of actuating operations of

the switch drive (2) are compared with one another for

determining a servicing requirement of the actuating force

coupling (12).

4. The method as claimed in claim 3, wherein a servicing

requirement of the actuating force coupling (12) is determined

in the event that a minimum target value of the determined

actuating force is undershot.

5. The method as claimed in one of claims 1 to 4, wherein

stored measurement signals of a plurality of actuating

operations of the switch drive (2) are used for determining a

wear condition of the actuating force coupling (12).

6. The method as claimed in one of claims 1 to 5, wherein

stored measurement signals of a plurality of actuating

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operations of the switch drive (2) are used for generating a

condition prognosis of the actuating force coupling (12).

7. The method as claimed in claim 6, wherein on the basis of

the generated condition prognosis of the actuating force

coupling (12), a future servicing time point is determined.

8. The method as claimed in one of claims 1 to 7, wherein the

measurement signals of the at least one sensor (20) are

continuously or temporally discretely recorded.

9. The method as claimed in one of claims 1 to 8, wherein the

measurement signals of the at least one sensor (20) are stored

and provided on an external server unit.

10. A switch drive system (1) having a measuring system (4)

for carrying out the method (30) as claimed in one of the

preceding claims and having a switch drive (2) for displacing

at least two switch blades (16) of a rail switch, having a

switch drive motor (8) for direct or indirect driving of an

actuating rod (10) which is connected to at least one switch

blade (16), via an actuating force coupling (12), and having a

drive electronics system (14) for controlling and regulating

the switch drive motor (8), wherein at least the switch drive

motor (8) and the actuating force coupling (12) are arranged

in an external housing (6) of the switch drive (2),

characterized in that at least one sensor (20) for measuring

sound waves is mountable on the external housing (6) and is

evaluable by a measuring electronics system (22), wherein on

the basis of measurement signals of the at least one sensor

(20), an actuating force of the actuating force coupling (12)

is measurable during an actuating operation of the switch

drive (2).

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11. The switch drive system as claimed in claim 10, wherein

the least one sensor (20) is a surface wave sensor.