Delay alarm device for circuit breaker and circuit breaker

Abstract

The embodiment of the utility model provides a time-delay alarm device for a circuit breaker and the circuit breaker. The time-delay alarm device for the circuit breaker and the circuit breaker are used for the circuit breaker. The delay alarm device comprises a first power supply; an output module coupled to the first power supply; the overload switch is arranged in series between the first power supply and the output module and is suitable for being closed when the current in the power utilization line exceeds a preset threshold value; and the time delay capacitor is arranged between the overload switch and the output module, one end of the time delay capacitor is coupled to the overload switch, the other end, opposite to the one end, of the time delay capacitor is grounded, and the output module comprises a comparator which is coupled to the time delay capacitor and is suitable for sending an overload signal to the alarm mechanism when the voltage of the time delay capacitor exceeds a preset voltage. Therefore, the false alarm time of the starting of the electric appliance can be covered, and meanwhile, the normal overload alarm function is not influenced.

Description

Technical Field

[0001] Example embodiments of the present disclosure generally relate to the field of electrical equipment, and more particularly, to a time-delay alarm device for a circuit breaker and a circuit breaker. Background Art

[0002] A circuit breaker is an electrical device that plays a key protective role in electrical circuits. It controls and protects circuits under both normal and fault conditions. In scenarios where power continuity is critical, even in the event of a circuit overload (current exceeding the rated value), electrical equipment must continue to operate. In these situations, a circuit breaker must be able to issue an alarm signal without interrupting the circuit, alerting users to circuit problems and enabling timely repairs. Utility Model Content

[0003] In a first aspect of the present disclosure, a time-delayed alarm device for a circuit breaker is provided. The time-delayed alarm device comprises: a first power supply; an output module coupled to the first power supply and adapted to transmit an overload signal to an alarm mechanism of the circuit breaker; an overload switch arranged in series between the first power supply and the output module and adapted to close when a current in a power line exceeds a predetermined threshold; and a time-delayed capacitor arranged between the overload switch and the output module, with one end of the time-delayed capacitor coupled to the overload switch and the other end of the time-delayed capacitor being grounded. The output module further comprises: a comparator coupled to the time-delayed capacitor and adapted to transmit an overload signal to the alarm mechanism when a voltage across the time-delayed capacitor exceeds a predetermined voltage.

[0004] In some embodiments, the delayed alarm device further includes: at least one current limiting resistor, arranged between the first power supply and the overload switch, and a first end of the current limiting resistor is coupled to the first power supply, and a second end of the current limiting resistor relative to the first end is coupled to the overload switch.

[0005] In some embodiments, at least one current limiting resistor includes multiple current limiting resistors, and the multiple current limiting resistors are arranged in parallel between the first power supply and the overload switch, and the delayed alarm device also includes: a switching switch, arranged between the multiple current limiting resistors and the overload switch, and the switching switch is coupled to the multiple current limiting resistors so that a specified current limiting resistor of the multiple current limiting resistors is connected to the overload switch.

[0006] In some embodiments, the plurality of current-limiting resistors include a first current-limiting resistor and a second current-limiting resistor, and a resistance value of the second current-limiting resistor exceeds a resistance value of the first current-limiting resistor.

[0007] In some embodiments, the overload switch includes: a bimetallic strip coupled to a power line and adapted to deform during a current overload in the power line; and a microswitch arranged between a first power supply and a time-delay capacitor, including: a first terminal coupled to the first power supply; and a second terminal coupled to the time-delay capacitor and adapted to turn on the first terminal during deformation of the bimetallic strip.

[0008] In some embodiments, the micro switch further includes a ground terminal arranged to be grounded and adapted to be connected to the second terminal during a period in which the first terminal is disconnected from the second terminal.

[0009] In some embodiments, the overload switch further includes: an alarm rod disposed between the bimetallic strip and the micro switch and movably coupled to the housing of the circuit breaker, so as to be pushed by the bimetallic strip and trigger the micro switch during deformation of the bimetallic strip.

[0010] In some embodiments, the alarm rod is movably coupled to the mounting post of the housing and is adapted to slide along the extension direction of the mounting post under the push of the bimetallic strip.

[0011] In some embodiments, the delayed alarm device further includes a second power supply coupled to the comparator and adapted to provide a predetermined voltage to the comparator.

[0012] During the period when the power line where the circuit breaker is located is overloaded, the overload switch of the delayed alarm device is closed, thereby turning on the capacitive resistance circuit inside the device. In this way, the first power supply can charge the delay capacitor. When the voltage across the delay capacitor is greater than the preset voltage of the comparator, the comparator sends an overload signal, instructing the alarm mechanism inside the circuit breaker to execute the alarm. In this way, the circuit breaker can delay the alarm after an overload current appears in the power line, thereby reducing the situation where the circuit breaker false alarms due to the long startup time of the electrical appliance. In addition, by reasonably adjusting the charging time of the delay capacitor, the false alarm time of the electrical appliance startup can be covered without affecting the normal overload alarm function.

[0013] In a second aspect of the present disclosure, a circuit breaker is provided, comprising: a housing, an alarm mechanism disposed within the housing, and the time-delay alarm device according to the first aspect of the present disclosure, coupled to the alarm mechanism and adapted to send an overload signal to the alarm mechanism.

[0014] It should be understood that the content described in this summary section is not intended to limit the key features or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, wherein:

[0016] Figure 1 A simplified schematic diagram of a circuit breaker according to some embodiments of the present disclosure is shown;

[0017] Figure 2 A circuit diagram of a time-delay alarm device according to some embodiments of the present disclosure is shown;

[0018] Figure 3 shows a schematic diagram of the internal structure of a circuit breaker according to some embodiments of the present disclosure; and

[0019] Figure 4 A simplified schematic diagram is shown showing the change in current in a power circuit when an electrical appliance is started according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0020] The following describes embodiments of the present disclosure in more detail with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are for illustrative purposes only and are not intended to limit the scope of protection of the present disclosure.

[0021] It should be noted that the titles of any section / subsection provided herein are not limiting. Various embodiments are described throughout this document, and any type of embodiment may be included under any section / subsection. Furthermore, the embodiments described in any section / subsection may be combined in any manner with any other embodiments described in the same section / subsection and / or in different sections / subsections.

[0022] In the description of the embodiments of the present disclosure, the term "including" and similar terms should be understood as open inclusion, that is, "including but not limited to". The term "based on" should be understood as "based at least in part on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The term "some embodiments" should be understood as "at least some embodiments". Other explicit and implicit definitions may be included below. The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may be included below.

[0023] As briefly mentioned above, when traditional overload alarm non-tripping circuit breakers are used in electrical appliances with long starting times, such as motors, the long starting current can easily cause the bimetallic strip in the circuit breaker to heat and deform, causing the circuit breaker to falsely alarm.

[0024] According to the time-delayed alarm device for circuit breakers and the circuit breaker provided by the present disclosure, the above-mentioned problems and other potential problems existing in traditional solutions are solved or at least partially solved. According to the time-delayed alarm device for circuit breakers in some embodiments of the present disclosure, the overload switch is closed during the period when the power line where the circuit breaker is located is overloaded, so that the capacitance circuit inside the device is turned on. Thus, the first power supply can charge the delay capacitor. When the voltage across the delay capacitor is greater than the preset voltage of the comparator, the comparator sends an overload signal, instructing the alarm mechanism inside the circuit breaker to execute the alarm. In this way, the circuit breaker can delay the alarm after an overload current appears in the power line, thereby reducing the situation where the circuit breaker false alarms due to the long startup time of the electrical appliance. In addition, by reasonably adjusting the charging time of the delay capacitor, the false alarm time of the electrical appliance startup can be covered without affecting the normal overload alarm function.

[0025] Figure 1 FIG. 1 shows a simplified schematic diagram of a circuit breaker according to some embodiments of the present disclosure. Figure 1 As shown, the circuit breaker generally comprises a housing 1, an alarm mechanism 2 disposed within the housing 1, and a time-delayed alarm device 3 coupled to the alarm mechanism 2. The circuit breaker is coupled to a power line. Therefore, if an overcurrent occurs in the power line and the duration of the overcurrent exceeds the delay time set by the time-delayed alarm device 3, the time-delayed alarm device 3 can send an overload signal to the alarm mechanism 2, causing the alarm mechanism 2 to issue an alarm indicating the current overload condition in the power line.

[0026] Figure 2 FIG. 1 shows a circuit diagram of a time-delay alarm device according to some embodiments of the present disclosure. Figure 2 As shown, the delayed alarm device 3 generally includes a first power supply 4, an output module coupled to the first power supply 4, a delay capacitor 8 arranged between the first power supply 4 and the output module, and an overload switch 6 for controlling the conduction between the delay capacitor 8 and the first power supply 4. When the overload switch 6 controls the conduction between the first power supply 4 and the delay capacitor 8, the first power supply 4 can charge the delay capacitor 8.

[0027] The output module includes a comparator 5. A first signal input 51 of the comparator 5 is coupled to a time-delay capacitor 8, and a second signal input 52 is adapted to receive a predetermined voltage. As the time-delay capacitor 8 charges, the voltage at the first signal input 51 of the comparator 5 gradually increases. If the voltage at the first signal input 51 of the comparator 5 exceeds the predetermined voltage at the second signal input 52, the output 53 of the comparator 5 can transmit an overload signal to the circuit breaker's alarm mechanism 2, indicating an overload on the power line.

[0028] In some embodiments, the delayed alarm device 3 further includes a second power supply 10, which is coupled to the second signal input terminal 52 of the comparator 5 and is adapted to provide a predetermined voltage to the second signal input terminal 52. In some embodiments, the second power supply 10 can be coupled to a power line and draw power from the power line, then provide the predetermined voltage to the second signal input terminal 52 of the comparator 5 after reducing or increasing the voltage. In some embodiments, the second power supply 10 can also be an independent power supply, which is not limited in this disclosure.

[0029] In some embodiments, the first power source 4 can be coupled to a power line and draw power from the power line to supply power to the delay capacitor 8. For example, the first power source 4 can provide 24V DC power to the delay capacitor 8. In some other embodiments, the first power source 4 can be an independent power supply.

[0030] In some embodiments, the delayed alarm device 3 also includes at least one current limiting resistor 7, one end of the current limiting resistor 7 is coupled to the first power supply 4, and the other end is coupled to the overload switch 6, so that the current limiting resistor 7 can limit the current of the charging circuit of the delay capacitor 8, thereby adjusting the charging time of the delay capacitor 8.

[0031] In some embodiments, the at least one current-limiting resistor 7 includes a plurality of current-limiting resistors 7, which are arranged in parallel between the first power source 4 and the overload switch 6. The time-delay alarm device 3 further includes a switch 9, one end of which is coupled to each of the plurality of current-limiting resistors 7, and the other end of which is coupled to the overload switch 6. The switch 9 is adapted to control a given current-limiting resistor 7 among the plurality of current-limiting resistors to be connected to the overload switch 6.

[0032] In some embodiments, the multiple current-limiting resistors 7 each have a different resistance value. For example, the resistance value of a first current-limiting resistor 7 among the multiple current-limiting resistors 7 exceeds the resistance value of a second current-limiting resistor 7 among the multiple current-limiting resistors 7. The switch 9 can adjust the charging time of the delay capacitor 8 by controlling the connection between different current-limiting resistors 7 and the overload switch 6. In this way, the alarm time of the delayed alarm device 3 can be adjusted to adapt the alarm time of the delayed alarm device 3 to different electrical appliances.

[0033] Figure 3FIG. 1 shows a schematic diagram of the internal structure of a circuit breaker according to some embodiments of the present disclosure. Figure 2 and Figure 3 As shown, in some embodiments, the overload switch 6 includes a bimetallic strip 61 coupled to the power line, and a microswitch 62. The microswitch 62 includes a first terminal 621 and a second terminal 622. The first terminal 621 is coupled to at least one current-limiting resistor 7, and the second terminal 622 is coupled to the delay capacitor 8. If an overcurrent occurs in the power line, the bimetallic strip 61 will deform due to temperature rise and trigger the microswitch 62, causing the first terminal 621 and the second terminal 622 of the microswitch 62 to conduct, thereby connecting the delay capacitor 8 to the first power source 4. The first power source 4 can charge the delay capacitor 8 via the current-limiting resistor 7.

[0034] In some embodiments, the overload switch 6 further includes an alarm lever 63, which is disposed between the bimetallic strip 61 and the microswitch 62 and is movably coupled to the circuit breaker housing 1. Thus, when the current in the power line is overloaded, the bimetallic strip 61 can push the alarm lever 63 to move, causing the alarm lever 63 to contact and trigger the microswitch 62. In some embodiments, the alarm lever 63 is coupled to the mounting post 11 of the circuit breaker housing 1 and is adapted to slide along the extension direction of the mounting post 11. Thus, the bimetallic strip 61 can push the alarm lever 63 to slide along the extension direction of the mounting post 11, causing the alarm lever 63 to trigger the microswitch 62. In some embodiments, a user can determine the current overload condition in the power line based on the position of the alarm lever 63.

[0035] In certain embodiments, microswitch 62 also includes ground terminal 623, and ground terminal 623 is suitable for being connected with second terminal 622 after the first terminal 621 of microswitch 62 is disconnected from second terminal 622.Along with the startup of electrical appliance, the circuit in the power circuit gradually recovers normal level.Bimetallic strip 61 recovers deformation, and microswitch 62 is released to trigger, and the first terminal 621 of microswitch 62 is disconnected from second terminal 622, and ground terminal 623 is electrically connected with second terminal 622.In this case, time-delay capacitor 8 two ends are grounded respectively, and time-delay capacitor 8 can discharge to the ground.Along with the continuous discharge of time-delay capacitor 8, if the voltage of time-delay capacitor 8 is less than the predetermined voltage of comparator 5 second signal input 52, output module stops sending overload signal to alarm module.

[0036] Figure 4 The following is a simplified schematic diagram showing the current changes in the power circuit when the electrical appliance is started according to some embodiments of the present disclosure. Figure 4 As shown, after electrical appliance A is started, the current in the power circuit is greater than the rated current in the time period 0-T0. After T0, the current in the power circuit returns to the normal rated current level. Figure 4 T1 represents the time required for the delay capacitor to charge to a voltage exceeding the predetermined value when the current-limiting resistor R1 is connected to the capacitive resistor circuit. T2 represents the time required for the delay capacitor to charge to a voltage exceeding the predetermined value when the current-limiting resistor R2 is connected to the capacitive resistor circuit. T3 represents the time required for the delay capacitor to charge to a voltage exceeding the predetermined value when the current-limiting resistor R3 is connected to the capacitive resistor circuit. Thus, the switch can be switched to the current-limiting resistor R3 to cover the false alarm time of the appliance A starting up without affecting the normal overload alarm function.

[0037] While various implementations of the present disclosure have been described above, the foregoing description is intended to be illustrative, not exhaustive, and not limited to the disclosed implementations. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described implementations. The terminology used herein is selected to best explain the principles of the implementations, their practical applications, or improvements to existing technologies, or to enable others skilled in the art to understand the various implementations disclosed herein.

Claims

1. A time-delay alarm device for a circuit breaker, characterized in that: include: a first power source (4); an output module coupled to the first power source (4) and adapted to send an overload signal to an alarm mechanism (2) of the circuit breaker; an overload switch (6) arranged in series between the first power source (4) and the output module and adapted to close during a period in which the current in the power line exceeds a predetermined threshold; as well as A time-delay capacitor (8) is arranged between the overload switch (6) and the output module, and one end of the time-delay capacitor (8) is coupled to the overload switch (6), and the other end of the time-delay capacitor (8) is grounded relative to the one end, and The output module comprises a comparator (5) coupled to the delay capacitor (8) and adapted to send an overload signal to the alarm mechanism (2) when the voltage of the delay capacitor (8) exceeds a predetermined voltage.

2. The delayed alarm device according to claim 1, characterized in that: Also includes: At least one current-limiting resistor (7) is arranged between the first power supply (4) and the overload switch (6), and a first end of the current-limiting resistor (7) is coupled to the first power supply (4), and a second end of the current-limiting resistor (7) opposite to the first end is coupled to the overload switch (6).

3. The delayed alarm device according to claim 2, characterized in that: The at least one current limiting resistor (7) includes a plurality of current limiting resistors (7), the plurality of current limiting resistors (7) are arranged in parallel between the first power source (4) and the overload switch (6), and The time-delay alarm device (3) further comprises: a switching switch (9) arranged between the plurality of current-limiting resistors (7) and the overload switch (6), and the switching switch (9) is coupled to the plurality of current-limiting resistors (7) so as to connect a designated current-limiting resistor (7) of the plurality of current-limiting resistors (7) to the overload switch (6).

4. The delayed alarm device according to claim 3, characterized in that: The multiple current-limiting resistors (7) include a first current-limiting resistor (7) and a second current-limiting resistor (7), and the resistance of the second current-limiting resistor (7) exceeds the resistance of the first current-limiting resistor (7).

5. The delayed alarm device according to any one of claims 1 to 4, characterized in that: The overload switch (6) comprises: a bimetallic strip (61) coupled to the power line and adapted to deform during a current overload in the power line; and A micro switch (62) is arranged between the first power supply (4) and the delay capacitor (8), comprising: A first terminal (621) coupled to the first power source (4); The second terminal (622) is coupled to the delay capacitor (8) and is suitable for turning on the first terminal (621) during the deformation of the bimetallic strip (61).

6. The delayed alarm device according to claim 5, characterized in that: The micro switch (62) further includes: The ground terminal (623) is arranged to be grounded and is suitable for being connected to the second terminal (622) during a period in which the first terminal (621) is disconnected from the second terminal (622).

7. The delayed alarm device according to claim 5, characterized in that: The overload switch (6) further comprises: An alarm rod (63) is arranged between the bimetallic strip (61) and the micro switch (62) and is movably coupled to the housing (1) of the circuit breaker so as to be pushed by the bimetallic strip (61) and trigger the micro switch (62) during deformation of the bimetallic strip (61).

8. The delayed alarm device according to claim 7, characterized in that: The alarm rod (63) is movably coupled to the mounting post (11) of the housing (1) and is adapted to slide along the extension direction of the mounting post (11) under the push of the bimetallic strip (61).

9. The time-delay alarm device according to any one of claims 1-4 and 6-8, characterized in that: The invention also comprises a second power supply (10), coupled to the comparator (5), and adapted to provide the predetermined voltage to the comparator (5).

10. A circuit breaker, characterized in that: include: housing (1), An alarm mechanism (2) is arranged in the housing (1); as well as The time-delay alarm device (3) according to any one of claims 1 to 9 is coupled to the alarm mechanism (2) and is suitable for sending an overload signal to the alarm mechanism (2).

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