Circuit breakers and methods for operating circuit breakers

Abstract

This disclosure provides a circuit breaker and a method for operating the circuit breaker. The circuit breaker includes a first circuit breaker terminal (11) and a second circuit breaker terminal (12), a bimetallic strip (13), a first conductive wire (14), a switch (40) having a first contact (41) and a second contact (42), a triggering device (44) mechanically coupling the bimetallic strip (13) to the switch (40), a magnet (17), and a detection device (20) including a magnetic field sensor (21) configured to detect the magnetic field of the magnet (17). The first conductive wire (14) is electrically coupled to the first circuit breaker terminal (11) and the first contact (41) and is wound around the bimetallic strip (13). The magnet (17) is connected to at least one of the bimetallic strip (13), the triggering device (44), and the switch (40).

Description

[0001] This disclosure relates to a circuit breaker and a method for operating the circuit breaker.

[0002] A circuit breaker can be set in both an open and closed position. This circuit breaker can be a motor protection circuit breaker (German: Motorschutzschalter). Typically, a circuit breaker includes an operating handle for manually setting the circuit breaker to the open or closed position. Additionally, the circuit breaker is configured to automatically set itself to the open position if the current flowing through it exceeds a predetermined value for a period of time or in the event of a short circuit. In the open position, no current flows through the circuit breaker. For example, a circuit breaker can be used to protect a motor or other electrical loads.

[0003] A circuit breaker includes at least one switch. The circuit breaker may include an auxiliary switch coupled to the at least one switch of the circuit breaker, and the auxiliary switch also changes its position when the switch of the circuit breaker changes its position from open to closed (or vice versa). The connection of the auxiliary switch to a control device can be used to provide the control device with information about the closed or open position of the circuit breaker.

[0004] One objective is to provide a circuit breaker and a method for operating the circuit breaker, which can provide information about the status of the circuit breaker with high efficiency.

[0005] This objective is achieved by the subject matter of the independent claim. Further developments and embodiments are described in the dependent claims.

[0006] Unless otherwise stated, the above definitions also apply to the following descriptions.

[0007] In one embodiment, a circuit breaker is disclosed, comprising a first circuit breaker terminal and a second circuit breaker terminal, a bimetallic strip, a first conductive wire, a switch having a first contact and a second contact, a triggering device mechanically coupled to the bimetallic strip to the switch, a magnet, and a detection device. The first conductive wire is electrically coupled to the first circuit breaker terminal and the first contact and is wound around the bimetallic strip. The magnet is connected to at least one of the bimetallic strip, the triggering device, and the switch. The detection device includes a magnetic field sensor for detecting the magnetic field of the magnet.

[0008] Advantageously, the magnetic field sensor of the detection device detects the magnetic field of the magnet. The bimetallic strip, the triggering device, or the switch is a mechanical moving part of the circuit breaker. Since the magnet is connected to one of the mechanical moving parts of the circuit breaker, the magnetic field sensor is able to detect the position of the mechanical moving part. Therefore, the detection device is configured to determine information about the state of the circuit breaker. Thus, the state of the circuit breaker is detected by an electrical method.

[0009] In one embodiment, the first conductive wire comprises a wire or conductive strip spirally wound around the bimetallic strip. The wire or conductive strip is configured to generate heat in the presence of current flow. The wire or conductive strip is a resistance heater.

[0010] In one embodiment, when the bimetallic strip is heated to a temperature above a predetermined temperature by current flowing through the first conductive wire, the triggering device sets the switch to the off position. The predetermined temperature can be set with tolerance.

[0011] In a further development, if the current value exceeds a first predetermined value for a predetermined time, the triggering device will set the switch to the off position.

[0012] In one embodiment, the triggering device converts the movement of the movable end of the bimetallic strip into the movement of the operating shaft of the switch.

[0013] In one embodiment, the magnetic field sensor includes a magnetoresistive sensor.

[0014] In one embodiment, the magnetoresistive sensor is implemented as one of anisotropic magnetoresistive sensor (AMR), giant magnetoresistive sensor (GMR), and tunneling magnetoresistive sensor (TMR).

[0015] In one embodiment, the magnetic field sensor includes a Hall effect sensor.

[0016] This magnetic field sensor can be implemented as a linear position sensor or a rotational angle position sensor.

[0017] In one embodiment, the detection device converts the position information of the magnet into a detection signal. This detection signal is an electrical detection signal.

[0018] In one embodiment, the detection device is configured to provide a detection signal indicating the position of at least one of the bimetallic strip, the triggering device, and the switch (e.g., the position of the operating shaft of the switch, the contact bridge of the switch, and / or at least one movable contact of the switch).

[0019] In one implementation, the detection signal can be implemented as an analog signal. This analog signal is a function of the magnet's position, such as a linear or nonlinear function.

[0020] In one implementation, the detection signal can be implemented as a digital signal. The digital signal can be a one-bit signal; for example, the detection signal indicates a tripped circuit breaker. Alternatively, the digital signal can provide more than one bit. The digital signal can indicate the position of a magnet with a resolution exceeding one bit.

[0021] In one implementation, the detection signal is implemented as a pulse width modulation signal.

[0022] In one implementation, the pulse width modulation signal has a duty cycle. The duty cycle is a function of the magnet's position, such as a linear or nonlinear function.

[0023] In an alternative implementation, the detection signal is implemented as an analog signal, such as a 0mA to 20mA signal or a 0V to 10V signal.

[0024] In an alternative implementation, the detection signal is implemented as a digital signal, such as a bus signal.

[0025] In one implementation, the detection signal is set when the load exceeds a first threshold.

[0026] In one embodiment, the detection device converts the position information of the magnet into an additional detection signal. This additional detection signal can be activated when the load exceeds a second threshold.

[0027] The load can be, for example, the value of the current flowing through the first conductor, the value of the temperature of the bimetallic strip, or the value of the position of the magnet. A value higher than 100% indicates an overload. A value up to 100% indicates a normal load. The first threshold and the second threshold are different. The first threshold and the second threshold can be, for example, 105% and 115% of the nominal value or continuous limit of the current, temperature, or position.

[0028] In one embodiment, the detection device includes a control circuit and at least a first output terminal. The control circuit is connected to the magnetic field sensor and the at least first output terminal.

[0029] The control circuit may include a communication module.

[0030] In one embodiment, the circuit breaker includes a first housing and a second housing. The first housing at least encloses the bimetallic strip, the first conductive wire, the switch, the triggering device, and the magnet.

[0031] In one embodiment, the second housing at least encloses the detection device.

[0032] The shape of the first housing can be adapted to the shape of the second housing.

[0033] The second housing can be configured such that it can be fixed to one side of the first housing. The first housing and the second housing can be interconnected.

[0034] In one embodiment, the circuit breaker includes an operating handle configured to manually set the circuit breaker to an open or closed position and mechanically connected to the triggering device.

[0035] The operating handle may be intended for manual release. The operating handle may be implemented, for example, as a toggle handle, a toggle switch, or a button.

[0036] In one embodiment, the switch includes at least one fixed contact and at least one movable contact. The fixed contact may be referred to as a static contact. The at least one fixed contact is immovably mounted in the first housing. The at least one movable contact is movably mounted in the first housing. The triggering device can be operatively connected to the at least one movable contact via the switch's operating shaft.

[0037] In one embodiment, the first and second contacts of the switch are implemented as a fixed contact and a movable contact, respectively. The operating shaft of the switch is connected to the movable contact.

[0038] In an alternative embodiment, both the first and second contacts of the switch are implemented as fixed contacts. The switch also includes a first and a second movable contact. The switch includes a contact bridge coupling the first movable contact to the second movable contact. The operating shaft of the switch is connected to the first and second movable contacts via the contact bridge.

[0039] In one embodiment, the triggering device performs the opening and closing of the switch. The switch has a first operating position and a second operating position implemented as an open position and a closed position.

[0040] The triggering device can be implemented as a tripping device, a switching mechanical system, and / or an actuating device. The triggering device may include a spring.

[0041] In one implementation, the circuit breaker is implemented as a thermal-magnetic circuit breaker.

[0042] In one embodiment, a method for operating a circuit breaker is disclosed, the method comprising: allowing current to flow through a first conductive line and a switch from a first circuit breaker terminal to a second circuit breaker terminal; heating a bimetallic strip through the first conductive line; moving a magnet according to the heat supplied to the bimetallic strip; and detecting the magnetic field of the magnet by a detection device including a magnetic field sensor. The conductive line is wound around the bimetallic strip. The bimetallic strip is mechanically coupled to the switch via a triggering device. The magnet is connected to at least one of the bimetallic strip, the triggering device, and the switch.

[0043] Advantageously, the current flowing through the first conductive line causes the magnet to move, and this movement is detected by the magnetic field sensor. Therefore, the detection device is configured to obtain information about the location of the circuit breaker.

[0044] The method for operating the circuit breaker can be implemented, for example, by means of a circuit breaker according to one of the examples above.

[0045] In one example, the circuit breaker is configured to provide overload indication using a magnetic field sensor, such as an AMR sensor. The circuit breaker is able to provide information about its overload condition. The detection and assessment of the circuit breaker's overload condition can be performed using the magnet and the magnetic field sensor. The magnet can be a permanent magnet. The magnet can be attached to the movable bridge of the triggering device. The movable bridge connects three bimetallic strips to another part of the triggering device. The magnetic field sensor is attached such that it can detect movement of the magnet, and therefore also movement of the bridge of the triggering device.

[0046] The circuit breaker can be manufactured as a motor protection switch, an overload protection switch, or an overload relay.

[0047] The detection device can be attached to the first housing and can also be detached. Therefore, the magnetic field sensor is located outside the first housing and detects the movement of the magnet inside the first housing.

[0048] In one implementation, an overload warning is evaluated and further processed in a control device. This control device can be implemented as a programmable logic controller (PLC, German: spéicherprogrammierbareSteuerung, abbreviated SPS). The overload warning can, for example, be forwarded via the control device and used for predictive maintenance applications. Furthermore, in the event of an overload, the control device can send a warning message to the circuit breaker to shut off a designated contactor or load before the circuit breaker trips. This allows for the implementation of an optional overload relay function (German: Überlastrelaisfunktion; abbreviated ZMR function). Additionally, in the event of an overload, the control device can send a shutdown control signal to a designated contactor of the circuit breaker before the circuit breaker trips.

[0049] In order to achieve the ZMR function independently of the control device, the control signal can control a simple control module on the contactor, thereby also achieving the ZMR function.

[0050] The following description of the accompanying drawings of the implementation scheme will further illustrate and explain various aspects of the circuit breaker. Parts and components with the same structure and effect are indicated by equivalent reference numerals. Descriptions of parts and components will not be repeated with respect to the following drawings, provided that they correspond to each other in terms of their function in different drawings.

[0051] Figures 1A to 1C An example of a circuit breaker is shown;

[0052] Figure 2A and Figure 2B An example of a magnetic field sensor and its characteristics is shown;

[0053] Figure 3 An example of an arrangement structure including a circuit breaker is shown; and

[0054] Figure 4 Another example of a circuit breaker is shown.

[0055] Figure 1A A schematic diagram of an example circuit breaker 10 having a first circuit breaker terminal 11 and a second circuit breaker terminal 12 is shown. For example, the first circuit breaker terminal 11 can be connected to a power source (not shown), and the second circuit breaker terminal 12 can be connected to a motor (not shown). Furthermore, the circuit breaker 10 includes a bimetallic strip 13 and a first conductive wire 14. The first conductive wire 14 is electrically connected to the first circuit breaker terminal 11. The first conductive wire 14 is wound around the bimetallic strip 13. The first conductive wire 14 is coupled to the second circuit breaker terminal 12 via a switch (not shown) of the circuit breaker 10. The bimetallic strip 13 has a fixed end 15 and a movable end 16. The circuit breaker 10 includes a magnet 17 that can be attached to the bimetallic strip 13. The magnet 17 can be fixed at the movable end 16 of the bimetallic strip 13.

[0056] Furthermore, the circuit breaker 10 includes a detection device 20, which includes a magnetic field sensor 21. The magnetic field sensor 21 is arranged near the magnet 17. The magnetic field sensor 21 is located in the magnetic field of the magnet 17. The detection device 20 includes a control circuit 22 connected to the magnetic field sensor 21. The control circuit 22 can be implemented as an application-specific integrated circuit, abbreviated as ASIC. The control circuit 22 can be implemented as a microcontroller or microprocessor. The control circuit 22 can be fabricated as a single-chip solution. The control circuit 22 is connected to a first output terminal 23 of the detection device 20 on its output side. The detection device 20 includes a first power supply terminal 24 that can be assigned to receive a supply voltage VDD. The supply voltage VDD can be a direct current voltage, abbreviated as DC voltage. For example, the supply voltage VDD can have a value of 24V. The detection device 20 includes a reference potential terminal 25.

[0057] The first power supply terminal 24 and the reference potential terminal 25 are connected to the control circuit 22. Furthermore, the first power supply terminal 24 and the reference potential terminal 25 can be connected to the magnetic field sensor 21 via a conductive line (not shown). The smoothing capacitor 26 of the detection device 20 can be coupled between the first power supply terminal 24 and the reference potential terminal 25. The detection device 20 includes a protection device 27 connected to the first power supply terminal 24 and an internal reference potential terminal 28. The internal reference potential terminal 28 can be directly connected to the reference potential terminal 25. The protection device 27 can be implemented as a Zener diode or a bidirectional suppression diode. The protection device 27 increases the electromagnetic compatibility (EMC) of the detection device 20.

[0058] The second output terminal 29 of the detection device 20 is connected to the reference potential terminal 25. The reference potential GND is set at the reference potential terminal 25. Figure 1A The possible terminal assignments of the detection device 20 are shown in the figure.

[0059] With the circuit breaker 10 in the closed position (which can be referred to as the conducting state), current I flows through the first conductor 14. Current I causes an increase in the temperature of conductor 14, which in turn causes an increase in the temperature of the bimetallic strip 13. This increase in temperature of the bimetallic strip 13 causes movement of the movable end 16 of the bimetallic strip 13. This movement remains very minimal even when current I is very low. Typically, the bimetallic strip 13 changes its curvature when heated.

[0060] Magnetic field sensor 21 detects the magnetic field generated by magnet 17. Magnetic field sensor 21 can be implemented as a magnetoresistive sensor, such as an anisotropic magnetoresistive sensor, abbreviated as AMR sensor. Magnetic field sensor 21 generates a sensor signal SE1, which is provided to control circuit 22. Control circuit 22 generates a detection signal SD1 and provides it to the first output terminal 23. Detection signal SD1 is an electrical detection signal. Detection signal SD1 can be implemented as a pulse width modulation signal. The duty cycle of the pulse width signal depends on sensor signal SE1, and therefore depends on the position of magnet 17.

[0061] If the current I changes the position of the magnet 17 due to the increased temperature of the bimetallic strip 13, the duty cycle of the detection signal SD1 changes. The duty cycle of the detection signal SD1 indicates the position of the magnet 17, and therefore the temperature of the bimetallic strip 13. Figure 1A Only a schematic diagram of circuit breaker 10 is shown, with some parts of circuit breaker 10 omitted. (The remaining text appears to be incomplete and possibly contains errors.) Figure 1A In the example shown, circuit breaker 10 can switch and control a current path.

[0062] Control circuit 22 can evaluate sensor signal SE1 with respect to at least one of the following characteristics:

[0063] - Control circuit 22 can determine the absolute position of magnet 17. This value corresponds to thermal memory or history.

[0064] - Control circuit 22 can determine the moving speed of magnet 17. This value can provide information about the triggering time, such as the expected triggering time.

[0065] - Control circuit 22 determines the direction of movement of magnet 17. The direction is opposite to the direction when the bimetallic strip 13 is cooled. Detection of heating may trigger circuit breaker 10 or disconnect the load.

[0066] In an alternative embodiment not shown, the detection device 20 includes a voltage converter that converts the supply voltage VDD into a lower voltage (e.g., 3.3 volts) supplied to the control circuit 22 and / or the magnetic field sensor 21.

[0067] In an alternative embodiment not shown, the detection device 20 includes a relay or solid-state contact connected on the output side to the first output terminal 23. In this case, the output may not be implemented as an "active output".

[0068] Figure 1B Another example of circuit breaker 10 is shown, which is Figure 1A A further development of the example shown. Circuit breaker 10 includes a switch 40 having a first contact 41 and a second contact 42. The first contact of switch 40 is coupled to a first conductive line 14. The second contact 42 of switch 40 is coupled to a second circuit breaker terminal 12. In a typical embodiment, circuit breaker 10 includes a coil 43, which is also included in the conductive path between the first circuit breaker terminal 11 and the second circuit breaker terminal 12. For example, coil 43 couples the first conductive line 14 to switch 40. Thus, the first circuit breaker terminal 11 is electrically connected to the second circuit breaker terminal 12 via a series circuit of the first conductive line 14, coil 43, and switch 40. However, the order of the first conductive line 14, coil 43, and switch 40 can be interchanged in this series connection.

[0069] Furthermore, the circuit breaker 10 includes a triggering device 44. A movable end 16 of the bimetallic strip 13 is mechanically connected to the triggering device 44. The triggering device 44 is mechanically connected to the switch 40. For example, the switch 40 includes an operating shaft 46 and at least one movable contact 48. The triggering device 44 is mechanically coupled to at least one movable contact 48 via the operating shaft 46.

[0070] exist Figure 1BIn the illustrated embodiment, switch 40 has a first fixed contact and a second fixed contact. The first contact 41 and the second contact 42 of switch 40 are implemented as a first fixed contact and a second fixed contact. Furthermore, switch 40 includes a first movable contact 48 and a second movable contact 49, and a contact bridge 50 connecting the first movable contact 48 to the second movable contact 49. When switch 40 is in the closed position (conductive state), the first contact 41 is in electrical contact with the first movable contact 48, and the second contact 42 is in electrical contact with the second movable contact 49. When switch 40 is in the open position, the first contact 41 and the second contact 42 are separated from the first movable contact 48 and the second movable contact 49. An operating shaft 46 positions switch 40 in the open and closed positions. Figure 1B In the illustrated embodiment, magnet 17 is connected to operating shaft 46. Magnetic field sensor 21 is placed near magnet 17.

[0071] In addition, the circuit breaker 10 includes an operating handle 52 mechanically coupled to the triggering device 44. Movement of the operating handle 52 (e.g., by an operator) can move the circuit breaker 10 from the open position to the closed position, or vice versa.

[0072] The flow of current I from the first circuit breaker terminal 11 to the second circuit breaker terminal 12 may cause a temperature rise in the bimetallic strip 13, thereby triggering the triggering device 44 and placing the circuit breaker 10 in the open position. This is achieved by movement of the operating shaft 46, which places the switch 40 in the open position. Due to the mass of the bimetallic strip 13 and the time constant for heating it, very short pulses in the current I do not cause movement of the movable end 16 of the bimetallic strip 13, thus failing to trigger the triggering device 44. However, if the current I exceeds a first predetermined value for a longer period of time (e.g., a predetermined time), movement of the bimetallic strip 13 causes movement of the operating shaft 46, which can be detected by the magnetic field sensor 21. Movement of the operating shaft 46 triggers the circuit breaker 10.

[0073] The coil 43 and the triggering device 44 are configured such that a current I exceeding a second predetermined value immediately triggers the triggering device 44, thereby setting the switch 40 to the open position. The coil 43 is designed to trigger the triggering device 44 in the event of a short circuit. Therefore, short-circuit protection is achieved by means of the coil 43.

[0074] In one example, magnetic field sensor 21 detects whether circuit breaker 10 is in the open or closed position.

[0075] In an alternative embodiment, magnet 17 is attached to a movable portion of triggering device 44. This movable portion is mechanically arranged between bimetallic strip 13 and operating shaft 46 of switch 40. Magnet 17 can be attached to such a movable portion of triggering device 44, which moves in response to movement of movable end 16 of bimetallic strip 13 before moving operating shaft 46 to set the switch from closed to open position. Therefore, magnetic field sensor 21 is capable of detecting the closed and open positions of switch 40 and intermediate states of circuit breaker 10. Thus, magnetic field sensor 21 is configured to detect current I in a range below a first predetermined value. In this range, circuit breaker 10 remains in the closed position. However, based on information that sensor signal SE1 rises from a normal value to a range close to the first predetermined value, detection device 20 is capable of generating detection signal SD1. Therefore, detection device 20 can be used to provide a warning message.

[0076] In one embodiment, magnet 17 and magnetic field sensor 21 are as follows: Figure 1A or Figure 4 Positioned as shown or as described above, and detecting movement of the movable portion of the bimetallic strip 13 and / or the movable bridge of the triggering device 44. The circuit breaker 10 may include an additional magnet, and the detection device 20 may include an additional magnetic field sensor. The additional magnet and the additional magnetic field sensor detect whether the circuit breaker 10 is in the open or closed position, and may, for example... Figure 1B The location is shown in the figure.

[0077] Figure 1C Another example of circuit breaker 10 is shown, which is Figure 1A and Figure 1B A further development of the example shown. Circuit breaker 10 includes a first housing 60 and a second housing 61. The second housing 61 encloses a detection device 20. The first housing 60 encloses a bimetallic strip 13, a first conductive wire 14, a switch 40, a triggering device 44, and a magnet 17. An operating handle 52 is located on the front side of the first housing 60. The operating handle 52 is connected to the triggering device 44 via a shaft (not shown) passing through an opening in the first housing 60. The first circuit breaker terminal 11 and the second circuit breaker terminal 12 are positioned so that they can be accessed from the outside. In addition, circuit breaker 10 includes a third circuit breaker terminal 63, a fourth circuit breaker terminal 64, a fifth circuit breaker terminal 65, and a sixth circuit breaker terminal 66. Additional circuit breaker terminals 63 to 66 are also located on the surface of the first housing 60 so that they can be accessed from the outside. The second housing 61 and the first housing 60 are configured such that the second housing 61 can be easily attached to the first housing 60.

[0078] Figure 2A It shows that it can be used as such Figures 1A to 1CAn example of a magnetic field sensor 21 in the circuit breaker 10 is shown. Such a magnetic field sensor 21 can be supplied, for example, by Murata Manufacturing Co., Ltd. of Japan. Figure 2A and Figure 2B The text describes a conventional magnetic field sensor 21. The magnetic field sensor 21 is implemented as a magnetoresistive sensor. Specifically, it is an anisotropic magnetoresistive sensor, abbreviated as AMR. Therefore, the magnetic field sensor 21 includes a first resistor 71 to a fourth resistor 74 connected to each other in the form of a Wheatstone bridge. The first resistor 71 and the second resistor 72 form a first series circuit, and the third resistor 73 and the fourth resistor 74 form a second series circuit. These two series circuits are connected between a power supply terminal 75 and an internal reference potential terminal 28. A first tap 77 is formed between the first resistor 71 and the second resistor 72. A second tap 78 is formed between the third resistor 73 and the fourth resistor 74. The first tap 77 and the second tap 78 are connected to a sensor circuit 79, which can be fabricated as an integrated circuit. The sensor circuit 79 can be implemented as a complementary metal-oxide-semiconductor circuit, abbreviated as CMOS circuit.

[0079] The sensor circuit 79 includes an amplifier 80 having two inputs connected to a first tap 77 and a second tap 78. The output of the amplifier 80 is coupled to the signal output 81 of the magnetic field sensor 21. The first power supply terminal 24 of the detection device 20 may be coupled to a power supply terminal 75, for example, via another switch 83. The sensor circuit 79 may include a latch circuit 84 and additional circuitry 85 that couples the output of the amplifier 80 to the signal output 81 of the magnetic field sensor 21. The sampling circuit 86 of the sensor circuit 79 is connected to the terminal of the other switch 83, the first power supply terminal 24, and the input of the latch circuit 84.

[0080] Advantageously, the magnetic field sensor 21, implemented as an AMR sensor, features a small sensor package, high sensitivity, and high reliability. The magnetic field sensor 21 can be housed in a small outline transistor package, abbreviated as SOT package.

[0081] Figure 2B As shown Figure 2A An example of the characteristics of the magnetic field sensor 21 is shown. Figure 2B The diagram shows the output voltage VOUT as a function of the magnetic field strength Hy measured in the y-direction. Furthermore, an auxiliary magnetic field Hx is applied to the magnetic field sensor 21 in the x-direction. The magnetic field sensor 21 can be configured to detect linear movement of the magnet 17.

[0082] In an alternative embodiment not shown, the magnetic field sensor 21 may be implemented using another sensor, such as a Hall effect sensor.

[0083] Figure 3An example arrangement 89 including the circuit breaker 10 as explained in the figure above is shown. Arrangement 89 also includes a control device 90. The control device 90 can be implemented as a programmable logic controller or a memory programmable controller, abbreviated as PLC. The control device 90 includes an input terminal 91 connected to the first output terminal 23 of the circuit breaker 10. Furthermore, the control device 90 includes a supply voltage terminal 92 and a reference potential terminal 93. The supply voltage terminal 92 is connected via a connecting wire to the first supply voltage terminal 24 of the circuit breaker 10 and a supply voltage source (not shown). The reference potential terminal 93 of the control device 90 is connected via a connecting wire to the reference potential terminal 25 and the second output terminal 29 of the detection device 20.

[0084] Input terminal 91 is a digital input. Input terminal 91 receives a detection signal SD1. Control device 90 is configured to evaluate the pulse-width modulated detection signal SD1. The detection signal SD1 has a low frequency. Therefore, control device 90 is able to evaluate the detection signal SD1. Due to the low frequency of the detection signal SD1, timing in control device 90 is not critical. Advantageously, circuit breaker 10 can transmit the detection signal SD1 to control device 90. Therefore, an increase in current I can be detected by detection device 20 and provided to control device 90. Therefore, control device 90 or another controller connected to control device 90 can be modified in the device connected to this arrangement 89, for example by modifying the state of the motor connected to circuit breaker 10. Therefore, arrangement 89 can react to an increase in current I before the triggering device 44 of circuit breaker 10 interrupts the flow of current I.

[0085] Control device 90 processes the detection signal SD1, which indicates an overload warning, and can provide warning information, maintenance information, and / or shutdown signals. The ZMR function can also be implemented using standard circuit breakers and contactors (which may be named, for example, DILM contactors). Control device 90 may include a standard interface connected to input terminal 91. The software of control device 90 is configured to evaluate the detection signal SD1, particularly the pulse-width modulated detection signal SD1.

[0086] Figure 4Another example of circuit breaker 10 is shown, which is a further development of the example shown above. As described above, circuit breaker 10 may include first circuit breaker terminals to sixth circuit breaker terminals 11, 12, 63 to 66. Therefore, circuit breaker 10 also includes additional bimetallic strips 100 and 101, second conductors 102 and 103, and additional switches 104 and 105. The third circuit breaker terminal 63 is coupled to the fourth circuit breaker terminal 64 via the second conductor 102 and the additional switch 104. Correspondingly, the circuit breaker terminal 65 is coupled to the sixth circuit breaker terminal 66 via the third conductor 103 and the additional switch 105.

[0087] The triggering device 44 is connected on its input side not only to the bimetallic strip 13, but also to another bimetallic strip 100 and an additional bimetallic strip 101. On its output side, the triggering device 44 is connected not only to the switch 40, but also to another switch 104 and an additional switch 105. To reduce... Figure 4 The complexity is reduced by omitting other parts of the circuit breaker 10, such as the three coils, operating handle 52, and most of the components of the triggering device 44.

[0088] Three bimetallic strips 13, 100, and 101 are connected in an OR configuration via a triggering device 44. Therefore, movement of any one of the three bimetallic strips 13, 100, and 101 is sufficient to trigger the triggering device 44, causing it to set the three switches 40, 104, and 105 to the off position. A magnet 17 can be fixed to the triggering device 44.

[0089] The triggering device 44 includes a movable bridge 106. The movable bridge 106 connects three bimetallic strips 13, 100, and 101. The movable bridge 106 performs the OR function of moving the three bimetallic strips 13, 100, and 101. The movable bridge 106 is coupled to the operating shafts of three switches 40, 104, and 105 via other parts of the triggering device 44 (not shown). Therefore, the circuit breaker 10 includes three current paths connected in parallel and can be turned on and off by the three switches 40. The three switches 40 operate simultaneously.

[0090] exist Figure 4 In the process, three bimetallic strips 13, 100, and 101 are bent to varying degrees. A small force F is applied to the movable bridge 106. Therefore, the bimetallic strip with the highest temperature among the three bimetallic strips 13, 100, and 101 determines the position of the movable bridge 106 (in the...). Figure 4 In this configuration, bimetallic strips 13 and 101 define the position of the movable bridge 106. Magnet 17 is fixed at the movable bridge 106. Therefore, the position of the bimetallic strip with the highest temperature is detected by the detection device 20.

[0091] The motor protection circuit breaker 10 protects motor or transformer loads from overload and short circuit. The overload detection principle is based on the mechanical force effect of bimetallic circuits. Due to excessive current, the bimetallic components (three parts in a three-phase circuit) in the circuit breaker 10 move mechanically, causing the circuit breaker 10 to trip. After the mechanical overload trip, the main current path is broken by the circuit breaker 10, thereby shutting off, for example, the motor load. Advantageously, the overload condition and / or tripping time of the circuit breaker 10 can be detected using a detection device 20. The detection device 20 alone, or in combination with the control device 90, can determine at least one of the following:

[0092] - Circuit breaker 10 has been turned off after the overload trip.

[0093] - Circuit breaker 10 tripped shortly before the overload trip point.

[0094] - Circuit breaker 10 has been turned off after the short circuit.

[0095] Overload or short circuit has caused circuit breaker 10 to trip.

[0096] Circuit breaker 10 uses detection device 20 to provide information about overload conditions. The detection and assessment of overload conditions are achieved via a magnet 17, which is a permanent magnet, and an AMR sensor. Magnet 17 may be fixed at a movable bridge 106 connecting three bimetallic strips 13, 100, 101, and is part of triggering device 44. Magnetic field sensor 21 (e.g., an AMR sensor) is located in a second housing 61, which may optionally include additional circuitry. Magnetic field sensor 21 is positioned such that it senses movement of magnet 17 and therefore also movement of movable bridge 106. Each movement may be related to an overload state of circuit breaker 10 (e.g., by detection device 20 itself or by control device 90), thereby enabling measurement.

[0097] Magnetic field sensor 21 is connected to control circuit 22 for evaluation. Detection device 20 can be inserted into a second housing 61, which can resemble the housing of an auxiliary switch. Detection device 20 can optionally be modified. Regardless of whether the customer intends to add detection device 20, magnet 17 must also be modified or fixed in circuit breaker 10. Detection device 20 can provide overload status, for example, via a detection signal SD1 in the form of a PWM signal at a first output terminal 23 as a digital output. Detection signal SD1 can be evaluated by a higher-level control device 90.

[0098] Alternatively, the detection device 20 includes two output terminals that provide a detection signal SD1 and another detection signal, for example, at 105% overload and 115% overload. The detection signal SD1 and the other detection signal can be static signals.

[0099] Alternatively, circuit breaker 10 includes exactly one current path (e.g., Figure 1A (as shown) or includes two or more than three current paths.

[0100] As mentioned above, Figures 1A to 4 The embodiments shown are examples of improved circuit breakers; therefore, they do not constitute a complete list of all embodiments based on improved circuit breakers. Actual circuit breakers may differ from the embodiments shown in, for example, in terms of components, structure, and shape. The terms "state" and "position" are interchangeable.

[0101] List of icon numbers

[0102] 10 circuit breakers

[0103] 11 First circuit breaker terminal

[0104] 12 Second Circuit Breaker Terminal

[0105] 13 Bimetallic Strips

[0106] 14 First Conduction Line

[0107] 15 Fixed End

[0108] 16 mobile devices

[0109] 17 magnets

[0110] 20 detection devices

[0111] 21 Magnetic Field Sensor

[0112] 22 Control Circuit

[0113] 23 First output terminal

[0114] 24 First power supply terminal

[0115] 26 smoothing capacitor

[0116] 25. Reference potential terminal of the detection device

[0117] 27 Protective Devices

[0118] 28 Internal reference potential terminals

[0119] 29 Second Output Terminal

[0120] 40 switches

[0121] 41 First Contact

[0122] 42 Second Contact

[0123] 43 coils

[0124] 44 triggering devices

[0125] 46 operating axes

[0126] 48 First movable contact

[0127] 49 Second movable contact

[0128] 50 contact bridge

[0129] 52 Operating Handle

[0130] 60 First shell

[0131] 61 Second shell

[0132] 63 Third Circuit Breaker Terminal

[0133] 64. Fourth circuit breaker terminal

[0134] 65 Fifth Circuit Breaker Terminal

[0135] 66 Sixth Circuit Breaker Terminal

[0136] 71 First Resistor

[0137] 72 Second Resistor

[0138] 73 Third Resistor

[0139] 74 Fourth Resistor

[0140] 75 power supply terminal

[0141] 77 First Tap

[0142] 78 Second Tap

[0143] 79 Sensor Circuit

[0144] 80 amplifier

[0145] 81 signal output

[0146] 83 Another switch

[0147] 84 latch circuit

[0148] 85 Another circuit

[0149] 86 sampling circuit

[0150] 89 Layout Structure

[0151] 90 control device

[0152] 91 Input Terminal

[0153] 92 power supply voltage terminal

[0154] 93 control device reference potential terminal

[0155] 100 additional bimetallic strips

[0156] 101 Additional Bimetallic Strip

[0157] 102 Second Conductor Line

[0158] 103 Third Conduction Line

[0159] 104 Other switches

[0160] 105 Additional Switch

[0161] 106 movable bridge

[0162] F force

[0163] GND reference potential

[0164] I current

[0165] HY, HX magnetic field strength

[0166] SD1 detection signal

[0167] SE1 sensor signal

[0168] VDD supply voltage

[0169] VOUT output voltage

Claims

1. A circuit breaker, the circuit breaker comprising: - First circuit breaker terminal (11) and second circuit breaker terminal (12). - Bimetallic strip (13). - First conduction line (14). - A switch (40) having a first contact (41) and a second contact (42), wherein a first conductive line (14) is electrically coupled to the first circuit breaker terminal (11) and the first contact (41) of the switch (40). - Triggering device (44), which mechanically couples the bimetallic strip (13) to the switch (40). - A magnet (17), the magnet being connected to at least one of the bimetallic strip (13), the triggering device (44), and the switch (40). - Detection device (20), the detection device includes a magnetic field sensor (21) and a control circuit (22), the magnetic field sensor is configured to detect the magnetic field of the magnet (17), and the control circuit (22) is connected to the magnetic field sensor (21). - A first housing (60) encloses at least the bimetallic strip (13), the first conductive wire (14), the switch (40), the triggering device (44), and the magnet (17), wherein the first conductive wire (14) is wound around the bimetallic strip (13), and - Second housing (61), the second housing at least encloses the detection device (20). The magnetic field sensor (21) is located outside the first housing (60) and is configured to detect the movement of the magnet (17) inside the first housing (60).

2. The circuit breaker according to claim 1, The first conductive line (14) includes a wire or conductive strip coiled around the bimetallic strip (13).

3. The circuit breaker according to claim 1 or 2, When the bimetallic strip (13) is heated to a temperature higher than a predetermined temperature by the current (I) flowing through the first conductive line (14), the triggering device (44) sets the switch (40) to the off position.

4. The circuit breaker according to claim 1 or 2, The triggering device (44) converts the movement of the movable end (16) of the bimetallic strip (13) into the movement of the operating shaft (46) of the switch (40).

5. The circuit breaker according to claim 1 or 2, The magnetic field sensor (21) mentioned therein includes a magnetoresistive sensor.

6. The circuit breaker according to claim 5, The magnetoresistive sensor is implemented as one of anisotropic magnetoresistive sensors, giant magnetoresistive sensors, and tunneling magnetoresistive sensors.

7. The circuit breaker according to claim 1 or 2, The magnetic field sensor (21) mentioned therein includes a Hall effect sensor.

8. The circuit breaker according to claim 1 or 2, The detection device (20) converts the position information of the magnet (17) into a detection signal (SD1).

9. The circuit breaker according to claim 8, The detection signal (SD1) is implemented as a pulse width modulation signal.

10. The circuit breaker according to claim 8, The detection device (20) converts the position information of the position of the magnet (17) into an additional detection signal, wherein the detection signal (SD1) is set when the load is higher than a first threshold, and wherein the additional detection signal is set when the load is higher than a second threshold.

11. The circuit breaker according to claim 1 or 2, The detection device (20) includes at least a first output terminal (23), and the control circuit (22) is also connected to the at least first output terminal (23).

12. The circuit breaker according to claim 1 or 2, The shapes of the first housing (60) and the second housing (61) are adapted to each other.

13. The circuit breaker according to claim 1 or 2, The circuit breaker (10) includes an operating handle (52) configured to manually set the circuit breaker (10) to an open or closed position and is mechanically connected to the triggering device (44).

14. A method for operating a circuit breaker, the method comprising: - Allow current (I) to flow from the first circuit breaker terminal (11) to the second circuit breaker terminal (12) through the first conductor (14) and the switch (40). - The first conductive line (14) heats the bimetallic strip (13), wherein the bimetallic strip (13) is mechanically coupled to the switch (40) via a triggering device (44). -Move magnet (17) according to heat supplied to the bimetallic strip (13), wherein the magnet (17) is connected to at least one of the bimetallic strip (13), the triggering device (44), and the switch (40), and - The magnetic field of the magnet (17) is detected by a detection device (20) including a magnetic field sensor (21) and a control circuit (22) connected to the magnetic field sensor (21). The circuit breaker includes a first housing (60) that encloses at least the bimetallic strip (13), the first conductive wire (14), the switch (40), the triggering device (44), and the magnet (17), wherein the first conductive wire (14) is wound around the bimetallic strip (13). The circuit breaker also includes a second housing (61), which at least encloses the detection device (20), and The magnetic field sensor (21) is located outside the first housing (60) and is configured to detect the movement of the magnet (17) inside the first housing (60).

Images