DE19524755A1 - Switch magnets stroke-monitoring device for electromagnetically operated switch - delivers binary signal denoting travel of armature on basis of derivative of coil current drawn through low-impedance transformer winding. - Google Patents
Switch magnets stroke-monitoring device for electromagnetically operated switch - delivers binary signal denoting travel of armature on basis of derivative of coil current drawn through low-impedance transformer winding.Info
- Publication number
- DE19524755A1 DE19524755A1 DE1995124755 DE19524755A DE19524755A1 DE 19524755 A1 DE19524755 A1 DE 19524755A1 DE 1995124755 DE1995124755 DE 1995124755 DE 19524755 A DE19524755 A DE 19524755A DE 19524755 A1 DE19524755 A1 DE 19524755A1
- Authority
- DE
- Germany
- Prior art keywords
- armature
- switch
- coil
- travel
- binary signal
- 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- Withdrawn
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F7/00—Magnets
- H01F7/06—Electromagnets; Actuators including electromagnets
- H01F7/08—Electromagnets; Actuators including electromagnets with armatures
- H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
- H01F7/1844—Monitoring or fail-safe circuits
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F7/00—Magnets
- H01F7/06—Electromagnets; Actuators including electromagnets
- H01F7/08—Electromagnets; Actuators including electromagnets with armatures
- H01F7/16—Rectilinearly-movable armatures
- H01F2007/1684—Armature position measurement using coils
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
- H01H2047/008—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current with a drop in current upon closure of armature or change of inductance
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
Abstract
Description
Schaltmagnete werden eingesetzt um mittels elektrischer Energie eine mechanische Bewe gung zu erreichen. Dazu wird ein bewegliches Teil (Anker) aus ferromagnetischem Material von einem Magnetfeld angezogen. Das Magnetfeld wird von einer Drahtspule erzeugt. Zur Überwachung der tatsächlichen Ankerbewegung werden oft zusätzliche Sensoren wie End schalter oder Näherungsinitiatoren eingesetzt.Switching magnets are used to mechanically use electrical energy to achieve. For this purpose, a moving part (armature) made of ferromagnetic material attracted to a magnetic field. The magnetic field is generated by a wire coil. For Monitoring the actual armature movement often becomes additional sensors like End switches or proximity switches used.
Nach dem Anlegen einer elektrischen Spannung an die Drahtspule würde sich der Strom nach der FormelAfter applying an electrical voltage to the wire coil, the current would flow back of the formula
aufbauen, wobeibuild up, in which
I = Strom durch die Spule,
U = Angelegte Spannung,
R = Ohmscher Widerstand im Spulenkreis,
L = Induktivität der Spule und
t = Verstrichene Zeit seit dem Anlegen der Spannung
ist.I = current through the coil,
U = applied voltage,
R = ohmic resistance in the coil circuit,
L = inductance of the coil and
t = elapsed time since the voltage was applied.
Der Strom baut sich jedoch nur dann nach dieser idealen "e-Funktion" auf, wenn die ange gebenen Konstanten sich während der Zeit t nicht verändern. Bei einem ordnungsgemäß funktionierenden Schaltmagneten ist dies jedoch nicht der Fall, weil sich die Induktivität L der Spule erhöht, während der Anker sich bewegt (angezogen wird). Die Spule erzeugt da durch eine Spannung Us, die der angelegten Spannung U entgegengerichtet ist. Damit wird während der Bewegung des Ankers der Strom I kleiner als es die "e-Funktion" erwarten läßt.However, the current builds up according to this ideal "e-function" only if the specified constants do not change during the time t. With a properly functioning switching magnet, however, this is not the case because the inductance L of the coil increases as the armature moves (is attracted). The coil generates a voltage U s which is opposite to the voltage U applied. The current I thus becomes smaller than the "e-function" would expect during the movement of the armature.
Es ist bekannt, daß die Stromanstiegskurve eines Schaltmagneten einen Einbruch aufweist, während der Anker sich bewegt. Dieser Einbruch kann als Kriterium für ein ordnungsgemä ßes Schalten des Schaltmagneten herangezogen werden.It is known that the current rise curve of a switching magnet has a dip, while the anchor is moving. This drop can serve as a criterion for a proper ß switching the switching magnet can be used.
Der Einbruch der Stromanstiegskurve ist jedoch von einer automatischen elektronischen Überwachungseinrichtung nur schwer zu erfassen, weil er in vielen Fällen nicht sehr ausge prägt, stark von der Schaltgeschwindigkeit abhängig oder stark verrauscht ist.However, the dip in the current rise curve is from an automatic electronic one Monitoring device difficult to detect because in many cases it is not very effective characterizes, strongly depends on the switching speed or is very noisy.
Diese Erfindung beschreibt eine Einrichtung, die ein einwandfreies Erkennen des Schaltvor ganges durch eine elektronische Schaltung ermöglicht.This invention describes a device which allows the switch to be correctly recognized ganges enabled by an electronic circuit.
Zunächst soll der theoretische Hintergrund der Erfindung erläutert werden. Hierzu wird auch Bezug genommen auf die Diagramme Fig. 1a-c. Die Maßstäbe dieser Diagramme sind relativ gewählt. Fig. 1a zeigt den typischen Stromverlauf in der Spule eines Schaltmagneten. Nach dem Anlegen der Spannung zum Zeitpunkt t = 0 steigt der Strom zunächst nach einer "e-Funktion" an, bis sich der Anker zu bewegen beginnt. Mit der Ankerbewegung wird die Stromanstiegsgeschwindigkeit kleiner bis hin zu negativen Werten. Sobald der Anker den Punkt der geringsten möglichen Reluktanz, z. B. durch einen mechanischen Anschlag, er reicht hat, nimmt der Strom weiter nach einer "e-Funktion" zu. Die durch die Ankerbewegung verursachte Einbuchtung der Stromanstiegskurve kann je nach den physikalischen Daten des Schaltmagneten stärker oder schwächer als in Fig. 1a dargestellt ausfallen. Um die Einbuch tung der Stromanstiegskurve ausgeprägter und damit besser erfaßbar zu machen, wird erfin dungsgemäß die mathematische Ableitung der Stromanstiegskurve gebildet. Die mathemati sche Ableitung der Stromanstiegskurve ist in relativem Maßstab in Fig. 1b dargestellt. Wird der Kurvenzug von Fig. 1b mit einem Schwellwert von z. B. 0,2 auf der relativen Skala von Fig. 1b verglichen, dem Zustand < = Schwellwert der Wert "0" und dem Zustand < Schwellwert der Wert "1" zugewiesen, erhält man eine binäre Aussage, aus der geschlossen werden kann, daß der Anker sich bewegt hat, wenn zu einem Zeitpunkt t = t₁, der abhängig von der physikali schen Auslegung des Schaltmagneten ist, das binäre Signal den Wert "1" hat. Hätte der An ker sich z. B. wegen eines Defekts des Schaltmagneten nicht bewegt, hätte das binäre Signal zu diesem Zeitpunkt den Wert "0". Der zeitliche Verlauf des binären Signals, bei ordnungs gemäßem Funktionieren des Schaltmagneten, ist in Fig. 1c dargestellt.First, the theoretical background of the invention will be explained. For this purpose, reference is also made to the diagrams Fig. 1a-c. The scales of these diagrams are chosen relatively. Fig. 1a shows a typical current waveform in the coil of a solenoid. After applying the voltage at time t = 0, the current initially rises according to an "e-function" until the armature begins to move. With the armature movement, the rate of current rise becomes smaller up to negative values. Once the anchor reaches the point of least possible reluctance, e.g. B. by a mechanical stop, he has enough, the current continues to increase after an "e-function". Depending on the physical data of the switching magnet, the indentation of the current rise curve caused by the armature movement can be stronger or weaker than shown in FIG. 1a. In order to make the registration of the current rise curve more pronounced and thus easier to grasp, the mathematical derivation of the current rise curve is formed according to the invention. The mathematical derivation of the current rise curve is shown on a relative scale in Fig. 1b. If the curve of Fig. 1b with a threshold of z. B. 0.2 compared on the relative scale of Fig. 1b, the state <= threshold value "0" and the state <threshold value "1" assigned, you get a binary statement from which it can be concluded that the armature has moved if at a time t = t 1, which is dependent on the physical design of the switching magnet, the binary signal has the value "1". If the anchor had z. B. not moving due to a defect of the switching magnet, the binary signal would have the value "0" at this time. The time course of the binary signal, with the proper functioning of the switching magnet, is shown in Fig. 1c.
In einem bevorzugten Ausführungsbeispiel wird ein Transformator zur Bildung der Ableitung der Stromanstiegskurve benutzt. Wird in die Primärwicklung eines Transformators ein Strom eingeprägt, so ist die in der Sekundärwicklung des Transformators induzierte Spannung pro portional zur Ableitung des Stromes in der Primärwicklung. Ein solches bevorzugtes Ausfüh rungsbeispiel ist in Fig. 2 dargestellt, auf die jetzt Bezug genommen wird.In a preferred embodiment, a transformer is used to form the derivative of the current rise curve. If a current is impressed into the primary winding of a transformer, the voltage induced in the secondary winding of the transformer is proportional to the derivation of the current in the primary winding. Such a preferred embodiment is shown in FIG. 2, to which reference is now made.
Die Batterie (1) dient zur Versorgung der Einrichtung mit elektrischer Energie. An Stelle der Batterie kann auch eine andere Vorrichtung, z. B. ein Netzteil, verwendet werden. Mit dem Schalter (2), der auch als elektronischer Schalter ausgeführt werden kann, wird der Strom durch die Primärwicklung (3) des Transformators und die Spule (5) des Schaltmagneten ein geschaltet. Die Primärwicklung (3) des Transformators ist so ausgeführt, daß ihre Impedanz klein gegenüber der Impedanz der Spule (5) des Schaltmagneten ist. Dadurch wird gewährlei stet, daß der Strom durch die Primärwicklung (3) und die Spule (5) in erster Linie von der Impedanz der Spule (5) abhängt und nur geringfügig durch die Primärwicklung (3) verändert wird. In einer im Labor realisierten Ausführung besteht die Primärwicklung (3) aus 3 Win dungen, was eine sehr kleine Impedanz gegenüber der Impedanz der Spule (5) darstellt. Die in der Sekundärwicklung (4) des Transformators erzeugte Spannung stellt ein Abbild der mathematischen Ableitung des in der Primärwicklung (3) und damit in der Spule (5) des Schaltmagnet fließenden Stromes dar. Um in der Sekundärwicklung (4) eine möglichst große Spannung zu erzeugen, die sich leicht auswerten läßt, erhält die Sekundärwicklung (4) eine große Windungszahl. In der bereits erwähnten labormäßigen Ausführung hat sich für die Se kundärwicklung eine Windungszahl von 1600 bewährt. Die in der Sekundärwicklung (4) erzeugte Spannung wird über das Widerstandsnetzwerk (7 und 8) der Basis des Transistors (9) zugeführt. Übersteigt die Spannung an der Basis des Transistors die Basisschaltschwelle, wird der Transistor leitend, und das Ausgangssignal am Ausgangsterminal (11) wechselt von "1" nach "0". Durch die Auslegung der Widerstände (7 und 8) kann das Verhaltnis der in der Sekundärspule (4) erzeugten Spannung zur Basisspannung des Transistors und damit die An sprechschwelle der Schaltung festgelegt werden. Durch die Diode (6) werden negative Span nungen vom Transistor (9) ferngehalten, der Widerstand (10) definiert das "1"-Signal am Ausgangsterminal (11) und das Ausgangsterminal (12) stellt einer nachfolgenden Schaltung das elektrische Bezugspotential zur Verfügung.The battery ( 1 ) is used to supply the device with electrical energy. Instead of the battery, another device, e.g. B. a power supply can be used. With the switch ( 2 ), which can also be designed as an electronic switch, the current through the primary winding ( 3 ) of the transformer and the coil ( 5 ) of the switching magnet is switched on. The primary winding ( 3 ) of the transformer is designed so that its impedance is small compared to the impedance of the coil ( 5 ) of the switching magnet. This ensu stet that the current is dependent through the primary winding (3) and the coil (5) primarily from the impedance of the coil (5) and is only slightly changed by the primary winding (3). In a version implemented in the laboratory, the primary winding ( 3 ) consists of 3 windings, which represents a very low impedance compared to the impedance of the coil ( 5 ). That in the secondary winding (4) of the transformer voltage generated is an image of the mathematical derivative of the in the primary winding (3) and thus in the coil (5) of the solenoid current flowing. Order in the secondary winding as large a voltage (4) generate that can be easily evaluated, the secondary winding ( 4 ) receives a large number of turns. In the laboratory version already mentioned, a number of turns of 1,600 has proven itself for secondary winding. The voltage generated in the secondary winding ( 4 ) is fed through the resistor network ( 7 and 8 ) to the base of the transistor ( 9 ). If the voltage at the base of the transistor exceeds the base switching threshold, the transistor becomes conductive and the output signal at the output terminal ( 11 ) changes from "1" to "0". By designing the resistors ( 7 and 8 ), the ratio of the voltage generated in the secondary coil ( 4 ) to the base voltage of the transistor and thus the response threshold of the circuit can be determined. The diode ( 6 ) keeps negative voltages away from the transistor ( 9 ), the resistor ( 10 ) defines the "1" signal at the output terminal ( 11 ) and the output terminal ( 12 ) provides a subsequent circuit with the electrical reference potential.
Claims (2)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1995124755 DE19524755A1 (en) | 1995-07-07 | 1995-07-07 | Switch magnets stroke-monitoring device for electromagnetically operated switch - delivers binary signal denoting travel of armature on basis of derivative of coil current drawn through low-impedance transformer winding. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1995124755 DE19524755A1 (en) | 1995-07-07 | 1995-07-07 | Switch magnets stroke-monitoring device for electromagnetically operated switch - delivers binary signal denoting travel of armature on basis of derivative of coil current drawn through low-impedance transformer winding. |
Publications (1)
Publication Number | Publication Date |
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DE19524755A1 true DE19524755A1 (en) | 1997-01-09 |
Family
ID=7766244
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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DE1995124755 Withdrawn DE19524755A1 (en) | 1995-07-07 | 1995-07-07 | Switch magnets stroke-monitoring device for electromagnetically operated switch - delivers binary signal denoting travel of armature on basis of derivative of coil current drawn through low-impedance transformer winding. |
Country Status (1)
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DE (1) | DE19524755A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2650517A1 (en) * | 2012-04-11 | 2013-10-16 | TI Automotive Fuel Systems SAS | Method for monitoring a fluid injection system and system thereof |
WO2017055031A1 (en) | 2015-10-02 | 2017-04-06 | BSH Hausgeräte GmbH | Household appliance |
EP3246718A4 (en) * | 2015-06-16 | 2018-03-14 | LG Chem, Ltd. | Transformation relay and battery voltage measurement system using same |
Citations (11)
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DE3150814A1 (en) * | 1981-12-22 | 1983-06-30 | Herion-Werke Kg, 7012 Fellbach | Device for the contact-free determination of the switching position of the armature of an electromagnet |
DE3615908A1 (en) * | 1986-05-12 | 1987-11-19 | Siemens Ag | Electromagnetic switching apparatus |
DE3807278A1 (en) * | 1988-03-05 | 1989-09-14 | Tech Ueberwachungs Verein Rhei | Method for the safety-testing of magnetic valves and measuring arrangement for carrying out the method |
DE3913222A1 (en) * | 1988-04-22 | 1989-11-23 | Tokyo Keiki Kk | ELECTROMAGNETIC DIRECTIONAL VALVE |
DE3817770A1 (en) * | 1988-05-26 | 1989-11-30 | Daimler Benz Ag | Device for the timed operation of an electromagnetic valve |
DE3925767A1 (en) * | 1988-10-25 | 1990-04-26 | Siemens Ag | Control procedure for electromechanical relay - using circuit to reduce coil current and maintain switched state after response |
DE4122348A1 (en) * | 1990-07-06 | 1992-01-23 | Jatco Corp | SOLENOID VALVE FAILURE DETECTING DEVICE |
DE4118975A1 (en) * | 1991-06-08 | 1992-12-10 | Vdo Schindling | Detecting position of core of electromagnetic control element - determining time required for current produced by pulses superimposed on control voltage to achieve defined change |
DE4129265A1 (en) * | 1991-08-30 | 1993-03-04 | Mannesmann Ag | ELECTROMAGNETIC SWITCHGEAR |
DE4208367A1 (en) * | 1992-03-16 | 1993-09-23 | Bosch Gmbh Robert | ELECTROMECHANICAL DOUBLE LIFT MAGNET |
DE4242432A1 (en) * | 1992-12-16 | 1994-06-23 | Ebern Fahrzeugtech Gmbh | Control of electromagnetic valve, solenoid rotary electromagnet or relay |
-
1995
- 1995-07-07 DE DE1995124755 patent/DE19524755A1/en not_active Withdrawn
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3150814A1 (en) * | 1981-12-22 | 1983-06-30 | Herion-Werke Kg, 7012 Fellbach | Device for the contact-free determination of the switching position of the armature of an electromagnet |
DE3615908A1 (en) * | 1986-05-12 | 1987-11-19 | Siemens Ag | Electromagnetic switching apparatus |
DE3807278A1 (en) * | 1988-03-05 | 1989-09-14 | Tech Ueberwachungs Verein Rhei | Method for the safety-testing of magnetic valves and measuring arrangement for carrying out the method |
DE3913222A1 (en) * | 1988-04-22 | 1989-11-23 | Tokyo Keiki Kk | ELECTROMAGNETIC DIRECTIONAL VALVE |
DE3817770A1 (en) * | 1988-05-26 | 1989-11-30 | Daimler Benz Ag | Device for the timed operation of an electromagnetic valve |
DE3925767A1 (en) * | 1988-10-25 | 1990-04-26 | Siemens Ag | Control procedure for electromechanical relay - using circuit to reduce coil current and maintain switched state after response |
DE4122348A1 (en) * | 1990-07-06 | 1992-01-23 | Jatco Corp | SOLENOID VALVE FAILURE DETECTING DEVICE |
DE4118975A1 (en) * | 1991-06-08 | 1992-12-10 | Vdo Schindling | Detecting position of core of electromagnetic control element - determining time required for current produced by pulses superimposed on control voltage to achieve defined change |
DE4129265A1 (en) * | 1991-08-30 | 1993-03-04 | Mannesmann Ag | ELECTROMAGNETIC SWITCHGEAR |
DE4208367A1 (en) * | 1992-03-16 | 1993-09-23 | Bosch Gmbh Robert | ELECTROMECHANICAL DOUBLE LIFT MAGNET |
DE4242432A1 (en) * | 1992-12-16 | 1994-06-23 | Ebern Fahrzeugtech Gmbh | Control of electromagnetic valve, solenoid rotary electromagnet or relay |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2650517A1 (en) * | 2012-04-11 | 2013-10-16 | TI Automotive Fuel Systems SAS | Method for monitoring a fluid injection system and system thereof |
EP3246718A4 (en) * | 2015-06-16 | 2018-03-14 | LG Chem, Ltd. | Transformation relay and battery voltage measurement system using same |
US10365333B2 (en) | 2015-06-16 | 2019-07-30 | Lg Chem, Ltd. | Transformation relay and battery voltage measurement system using same |
WO2017055031A1 (en) | 2015-10-02 | 2017-04-06 | BSH Hausgeräte GmbH | Household appliance |
DE102015219145A1 (en) | 2015-10-02 | 2017-04-06 | BSH Hausgeräte GmbH | household appliance |
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