High-stability load switch

Abstract

The utility model discloses a high-stability load switch, belongs to the technical field of load switches, and solves the problem that a circuit is cut off after the load switch can be maintained for a certain time when current overload occurs. And the problem that normal operation of other electrical components on the circuit is influenced by circuit disconnection caused by temporary overload of the current is avoided. Comprising a wire inlet cabinet and a loop outlet cabinet, the loop outlet cabinet comprises a common resistor and a fuse which are connected in series, two ends of the common resistor are respectively connected with a first current detection and control circuit and a voltage stabilizing resistor in parallel, and two ends of the voltage stabilizing resistor are connected with a second current detection and control circuit in parallel. And the first current detection and control circuit controls the access of the voltage stabilizing resistor and controls the short circuit of the fuse. When the load switch works, the current is monitored through the current sensor, the voltage comparator is triggered after time delay, the triode and the relay are controlled to realize voltage reduction or disconnection of the circuit, and electrical components are prevented from being damaged due to transient overload.

Description

Technical Field

[0001] The utility model relates to the technical field of load switches, in particular to a high-stability load switch. Background Art

[0002] A load switch is a switching device used to control and protect loads in a circuit. It safely operates the circuit under load current, meaning it can close and open the circuit while energized. Unlike circuit breakers, load switches do not automatically interrupt short-circuit currents and are therefore typically used in conjunction with other protective components such as fuses. Load switches are suitable for low-current, low-voltage applications, such as home lighting systems or small motor starter control.

[0003] Load switches feature simple structure, easy operation, safety, and reliability, making them widely used in power systems, industrial automation, and household appliances. They can be operated manually or remotely controlled via a motor. The primary function of a load switch is to switch the load in a circuit, allowing it to disconnect or connect when needed.

[0004] Ordinary load switches include incoming line cabinets and ring-out cabinets. Fuses are often installed in the circuits in the ring-out cabinets. When the circuit load current is overloaded, that is, the load switch exceeds the load of the circuit, the fuse will eventually blow. However, load switches are used in more important scenarios in commonly used circuits. Once the current in the circuit is temporarily overloaded, the load switch will be disconnected, eventually causing damage to various electrical components connected to the circuit. Therefore, even if the current is overloaded, the load switch needs to be able to maintain the circuit for a certain period of time before cutting off the circuit to avoid the circuit being disconnected due to temporary current overload, affecting the normal operation of other electrical components on the circuit.

[0005] Therefore, a high-stability load switch is proposed to solve or alleviate the above problems. Utility Model Content

[0006] The purpose of the utility model is to solve the shortcomings of the prior art and to propose a high-stability load switch.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A high-stability load switch includes an incoming line cabinet and a loop-out cabinet. The loop-out cabinet includes a common resistor and a fuse connected in series. A first current detection circuit and a voltage-stabilizing resistor are respectively connected in parallel at both ends of the common resistor. A second current detection circuit is connected in parallel at both ends of the voltage-stabilizing resistor. The first current detection circuit controls the voltage-stabilizing resistor path and controls the fuse to short-circuit. The second current detection circuit controls the voltage-stabilizing resistor to open and controls the fuse path.

[0009] Preferably, the resistance of the voltage-stabilizing resistor is greater than the resistance of an ordinary resistor.

[0010] Preferably, the first current detection circuit includes

[0011] a first current sensor, which collects the current in the loop where the ordinary resistor is located and outputs a first current signal;

[0012] a first delay circuit, wherein the output terminal of the first current sensor is coupled to the input terminal of the first delay circuit, the first delay circuit starts timing in response to the first current signal and outputs a first delay signal after the timing time ends;

[0013] A first switching circuit, wherein the input end of the first switching circuit is coupled to the output end of the first delay circuit, the output end of the first switching circuit is coupled to a first relay, the first switching circuit controls the first relay in response to a first delay signal, and the first relay controls the circuit path where the voltage-stabilizing resistor is located and controls the circuit where the fuse is located to be disconnected.

[0014] Preferably, the first delay circuit includes an RC delay circuit, the first switching circuit includes a first voltage comparator and a first transistor switch, the input end of the first voltage comparator is coupled to the output end of the RC delay circuit, the base of the first transistor switch is coupled to the output end of the first voltage comparator, the collector of the first transistor switch is coupled to the first relay and then connected to an electrical setting, and the emitter of the first transistor switch is grounded.

[0015] Preferably, the second current detection circuit includes

[0016] a second current sensor, which collects the current of the loop where the voltage-stabilizing resistor is located and outputs a second current signal;

[0017] a second delay circuit, wherein the output terminal of the second current sensor is coupled to the input terminal of the second delay circuit, the second delay circuit starts timing in response to the second current signal and outputs a second delay signal after the timing time ends;

[0018] The second switching circuit, the input end of the second switching circuit is coupled to the output end of the second delay circuit, the output end of the second switching circuit is coupled to the second relay, the second switching circuit controls the second relay in response to the second delay signal, and the second relay controls the circuit where the voltage stabilizing circuit is located to be disconnected and controls the circuit path where the fuse is located.

[0019] Preferably, the second delay circuit includes an RC delay circuit, the second switching circuit includes a second voltage comparator and a second triode switch, the input end of the second voltage comparator is coupled to the output end of the RC delay circuit, the base of the second triode switch is coupled to the output end of the second voltage comparator, the collector of the second triode switch is coupled to the second relay and then connected to an electrical setting, and the emitter of the second triode switch is grounded.

[0020] The utility model has the following beneficial effects:

[0021] In the present invention, the load switch receives power through the incoming cabinet and outputs power through the outgoing cabinet. During the power inflow and outflow process, the first current sensor monitors the current of the common resistance loop and outputs a first current signal. This signal causes the RC delay circuit to start charging. After charging is completed, the first delay signal activates the first voltage comparator, which compares the delay signal with the reference signal. If the reference signal is exceeded, the comparator sends a first comparison signal to the first transistor switch, turning it on, triggering the first relay, and controlling the closure of related switches to realize the energization of the voltage-stabilizing resistor and the voltage reduction of the circuit, thereby reducing the overload current.

[0022] Subsequently, the second current sensor monitors the current in the voltage-stabilizing resistor loop and outputs a second current signal, which starts the second delay circuit. Its delay signal activates the second voltage comparator after charging is completed. If the signal exceeds the reference, the second comparison signal will activate the second transistor switch, energizing the second relay, causing the relevant relay switch to disconnect, restoring the path of the ordinary resistor and the fuse, and thus blowing the fuse. This design allows the load switch to delay action after current overload, avoiding immediate circuit disconnection due to temporary overload, and protecting electrical components from damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 This is the wiring diagram of the utility model. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0028] In the description of the present invention, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the utility model product is usually placed when in use, or are the orientation or position relationship commonly understood by those skilled in the art. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0029] Furthermore, the terms “first,” “second,” “third,” etc., are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0030] It should also be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0031] A high stability load switch, such as Figure 1As shown, it includes an incoming line cabinet and a ring-out cabinet. The ring-out cabinet includes an ordinary resistor and a fuse connected in series. A first current detection circuit and a voltage-stabilizing resistor are respectively connected in parallel at both ends of the ordinary resistor. A second current detection circuit is connected in parallel at both ends of the voltage-stabilizing resistor. The first current detection circuit controls the voltage-stabilizing resistor path and controls the fuse short circuit. The second current detection circuit controls the voltage-stabilizing resistor open circuit and controls the fuse path. The resistance value of the voltage-stabilizing resistor is greater than that of the ordinary resistor.

[0032] The first current detection circuit includes a first current sensor, a first delay circuit, and a first switch circuit. The first current sensor collects the current in the loop where the common resistor is located and outputs a first current signal. The output of the first current sensor is coupled to the input of the first delay circuit. The first delay circuit starts timing in response to the first current signal and outputs a first delay signal after the timing expires. The input of the first switch circuit is coupled to the output of the first delay circuit. A first relay is coupled to the output of the first switch circuit. The first switch circuit controls the first relay in response to the first delay signal. The first relay controls the path of the loop where the voltage-stabilizing resistor is located and controls the disconnection of the loop where the fuse is located. The first delay circuit includes an RC delay circuit. The first switch circuit includes a first voltage comparator and a first transistor switch. The input of the first voltage comparator is coupled to the output of the RC delay circuit. The base of the first transistor switch is coupled to the output of the first voltage comparator. The collector of the first transistor switch is coupled to the first relay and then connected to an electrical source. The emitter of the first transistor switch is grounded.

[0033] The second current detection circuit includes a second current sensor, a second delay circuit, and a second switch circuit. The second current sensor collects the current in the loop where the voltage-stabilizing resistor is located and outputs a second current signal. The output end of the second current sensor is coupled to the input end of the second delay circuit. The second delay circuit responds to the second current signal and starts timing and outputs a second delay signal after the timing time ends. The input end of the second switch circuit is coupled to the output end of the second delay circuit. A second relay is coupled to the output end of the second switch circuit. The second switch circuit controls the second relay in response to the second delay signal. The second relay controls the loop where the voltage-stabilizing circuit is located to disconnect and controls the loop where the fuse is located to pass. The second delay circuit includes an RC delay circuit. The second switch circuit includes a second voltage comparator and a second transistor switch. The input end of the second voltage comparator is coupled to the output end of the RC delay circuit. The base of the second transistor switch is coupled to the output end of the second voltage comparator. The collector of the second transistor switch is coupled to the second relay and then connected to an electrical setting. The emitter of the second transistor switch is grounded.

[0034] When the load switch of the present invention is used normally, power is input from the incoming line cabinet and output from the outgoing line cabinet. During the process of power input and output, the current size of the loop where the ordinary resistor is located is detected by the first current sensor, and then a first current signal is output. The first current signal is given to the capacitor in the first delay circuit of the RC delay circuit and starts charging. After the charging is completed, a first delay signal is output to the input end of the first voltage comparator in the first voltage comparison circuit. Then the first voltage comparator compares the size of the first delay signal with the first reference signal. After determining that it is greater than, it outputs the first comparison signal to the base of the first transistor switch, so that the collector and emitter of the first transistor switch are turned on, and then the first relay is energized. The first relay will control the first relay switch 1 and the first relay switch 2 to be closed, so that the voltage-stabilizing resistor is energized, and then the voltage of the loop where the ordinary resistor is located is reduced, and then the overloaded current is reduced. Then the current size of the loop where the voltage-stabilizing resistor is located is measured by the second current sensor. The first circuit detects the current and outputs a second current signal. The second current signal is fed to the capacitor in the second delay circuit, which is an RC delay circuit, and then begins to charge. After charging is completed, a second delay signal is output to the input of the second voltage comparator in the second voltage comparison circuit. The second voltage comparator then compares the second delay signal with the second reference signal. When it is determined that the second delay signal is greater than the second reference signal, it outputs a second comparison signal to the base of the second transistor switch, causing the collector and emitter of the second transistor switch to conduct, thereby energizing the second relay. The normally closed second relay switch 1 connected in series with the circuit where the voltage-stabilizing resistor is located is disconnected, and the normally closed second relay switch 2 connected in series with the first relay switch 2 is disconnected, thereby opening the circuit where the ordinary resistor and the fuse are located, and then causing the fuse to melt. In this way, the load switch can block the circuit after a period of time, rather than immediately blocking the circuit when a current overload occurs, thereby preventing electrical components in the circuit from being easily disconnected and damaged due to temporary current overload.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A high stability load switch, characterized in that: It includes an incoming line cabinet and a loop-out cabinet. The loop-out cabinet includes a common resistor and a fuse connected in series. A first current detection circuit and a voltage-stabilizing resistor are respectively connected in parallel at both ends of the common resistor. A second current detection circuit is connected in parallel at both ends of the voltage-stabilizing resistor. The first current detection circuit controls the voltage-stabilizing resistor path and controls the fuse short circuit. The second current detection circuit controls the voltage-stabilizing resistor open circuit and controls the fuse path.

2. A high stability load switch according to claim 1, characterized in that: The resistance of the voltage-stabilizing resistor is greater than the resistance of an ordinary resistor.

3. A high stability load switch according to claim 1, characterized in that: The first current detection circuit includes a first current sensor, which collects the current in the loop where the ordinary resistor is located and outputs a first current signal; a first delay circuit, wherein the output terminal of the first current sensor is coupled to the input terminal of the first delay circuit, the first delay circuit starts timing in response to the first current signal and outputs a first delay signal after the timing time ends; A first switching circuit, wherein the input end of the first switching circuit is coupled to the output end of the first delay circuit, the output end of the first switching circuit is coupled to a first relay, the first switching circuit controls the first relay in response to a first delay signal, and the first relay controls the circuit path where the voltage-stabilizing resistor is located and controls the circuit where the fuse is located to be disconnected.

4. A high stability load switch according to claim 3, characterized in that: The first delay circuit includes an RC delay circuit, and the first switching circuit includes a first voltage comparator and a first transistor switch. The input end of the first voltage comparator is coupled to the output end of the RC delay circuit, the base of the first transistor switch is coupled to the output end of the first voltage comparator, the collector of the first transistor switch is coupled to the first relay and then connected to an electrical setting, and the emitter of the first transistor switch is grounded.

5. The high stability load switch according to claim 1, characterized in that: The second current detection circuit includes a second current sensor, which collects the current of the loop where the voltage-stabilizing resistor is located and outputs a second current signal; a second delay circuit, wherein the output terminal of the second current sensor is coupled to the input terminal of the second delay circuit, the second delay circuit starts timing in response to the second current signal and outputs a second delay signal after the timing time ends; The second switching circuit, the input end of the second switching circuit is coupled to the output end of the second delay circuit, the output end of the second switching circuit is coupled to the second relay, the second switching circuit controls the second relay in response to the second delay signal, and the second relay controls the circuit where the voltage stabilizing circuit is located to be disconnected and controls the circuit path where the fuse is located.

6. A high stability load switch according to claim 5, characterized in that: The second delay circuit includes an RC delay circuit, and the second switch circuit includes a second voltage comparator and a second transistor switch. The input end of the second voltage comparator is coupled to the output end of the RC delay circuit, the base of the second transistor switch is coupled to the output end of the second voltage comparator, the collector of the second transistor switch is coupled to the second relay and then connected to an electrical setting, and the emitter of the second transistor switch is grounded.

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