A voltage limiting overvoltage protection assembly with a recoverable electromagnetic drive trip mechanism

Abstract

The application discloses a voltage-limited overvoltage protection component with a recoverable electromagnetic drive tripping mechanism, which is composed of a voltage-limited overvoltage protector and an electromagnetic drive tripping mechanism. In a normal state, the normally closed contact of the electromagnetic drive tripping mechanism is in a closed state, which does not affect the normal working state of the voltage-limited overvoltage protector and the protection state under a normal intensity overvoltage. When an overvoltage occurs, a pulse current flowing through the voltage-limited pressure-sensitive resistor induces a current in the upper metal disc of the electromagnetic drive tripping mechanism, which is opposite to the direction of the spiral conductor coil of the lower electromagnetic drive disc, so that the upper metal disc of the lower electromagnetic drive mechanism induces an electromagnetic repulsive force with the lower electromagnetic drive disc, thereby causing the normally closed contact of the electromagnetic drive tripping mechanism to break, effectively inhibiting the continuous effect of a subsequent power frequency or direct current arc on the voltage-limited protector, prolonging the service life of the voltage-limited overvoltage protection component, and effectively realizing the safe use coefficient and prolonging the service life of the voltage-limited overvoltage protection component.

Description

Technical Field

[0001] This invention relates to an overvoltage protector, and more particularly to a voltage-limiting overvoltage protection component with a resettable electromagnetically driven tripping mechanism. Background Technology

[0002] With the advancement of technology in electronic and information systems, the impact and harm of overvoltage on sensitive electronic equipment and communication devices with weak immunity are becoming increasingly severe. Overvoltage protection is an important guarantee for the safe operation of communication systems.

[0003] Since the advent of the voltage-limiting overvoltage protector—the varistor—developed by Panasonic of Japan, many domestic research institutions and manufacturers have carried out research on the materials, formulations, and processes of voltage-limiting varistors. They have been increasingly widely used in communication power supplies and signal overvoltage protection applications in the field of communication. At the same time, in the intelligent aspects of remote signaling and remote control, functions such as failure indication of varistors or surge protectors have been proposed and implemented.

[0004] Under overvoltage conditions, voltage-limiting varistors exhibit low dynamic impedance. However, under high-amplitude direct lightning currents, lightning-induced impulse currents, and switching impulse currents, they will generate significant Joule heating, potentially leading to cracking or even combustion due to thermal stress. To prevent thermal cracking and combustion of voltage-limiting varistors, invention patents CN 109923625, CN113192713, and CN112489905 disclose a varistor overvoltage protection component with thermal protection function, formed by connecting a thermal element in series with a voltage-limiting varistor. Theoretically, a thermally heated varistor can effectively solve the problem of cracking or combustion of voltage-limiting protectors. However, the following problems still exist:

[0005] When lightning impulse current flows through a thermistor, the melting of the thermal fuse is a process that has a nonlinear relationship with the lightning impulse current, and the melting characteristics of the thermal fuse are unstable.

[0006] The melting of a thermal fuse is an irreversible process that cannot be recovered, and the melting of a thermal fuse indicates permanent damage to a voltage-limiting varistor. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a voltage-limiting overvoltage protection component with a recoverable electromagnetic drive tripping mechanism. This avoids the unreliability and non-reusability issues of existing technologies that rely on thermal fuses or solder joints to melt due to overheating, thus effectively improving the safety factor and extending the service life of the voltage-limiting overvoltage protection component.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism includes a voltage-limiting overvoltage protection element and a resettable electromagnetic drive tripping mechanism.

[0010] The resettable electromagnetic drive tripping mechanism includes a pair of normally closed contacts, a retractable spring mechanism, and an electromagnetic drive mechanism installed in an insulating housing. The upper and lower ends of the insulating housing are closed by an upper flange and a lower flange, respectively. The upper electrode of the normally closed contact is a movable contact. The upper and lower electrodes of the normally closed contact are led out to an upper connection terminal and a lower connection terminal through the upper flange and the lower flange, respectively. The lower end of the voltage-limiting overvoltage protection element is electrically connected to the upper connection terminal of the normally closed contact, forming a series structure voltage-limiting overvoltage protection assembly. The upper end of the voltage-limiting overvoltage protection element and the lower connection terminal of the normally closed contact serve as the high-voltage terminal HV and the low-voltage terminal LV of the voltage-limiting overvoltage protection assembly, respectively.

[0011] The retractable spring mechanism is installed between the normally closed contact electrode and the upper flange, and is in a natural extension / retraction state under normal conditions. The lower end of the retractable spring is fixedly installed on the lower surface of the normally closed contact electrode through insulation, and the upper end of the retractable spring is fixed to the upper flange.

[0012] The electromagnetic drive mechanism includes an upper metal disk and a lower electromagnetic drive disk. The upper metal disk is fixed to the bottom of the electrode on the normally closed contact, and the lower electromagnetic drive disk is fixed in the insulating shell and is located below the upper metal disk. When not energized, the two are in contact. A spiral conductor coil is fixed in the lower electromagnetic drive disk, and the current flowing through the spiral conductor coil is taken from the pulse current signal of the voltage-limiting overvoltage protection element.

[0013] Furthermore, the lower electromagnetic drive disk of the electromagnetic drive mechanism is fixed to the lower flange or to the insulating shell by an insulating rod, and the spiral conductor coil is led out from the side of the insulating shell.

[0014] Furthermore, the lower electromagnetic drive disk of the electromagnetic drive mechanism is an insulating disk engraved with circular or rectangular spiral lines, and a spiral conductor coil is fixed in the circular or rectangular spiral groove of the insulating disk.

[0015] Furthermore, the voltage-limiting overvoltage protection element is a varistor.

[0016] Furthermore, the surface of the upper electrode of the normally closed contact is larger than the surface of the lower electrode.

[0017] Furthermore, the voltage-limiting overvoltage protection element is installed separately in a closed unit, or it is installed together with the resettable electromagnetic drive tripping mechanism in a closed unit, and the size of the closed unit is 1P or 2P.

[0018] This invention relates to a voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism. It mainly consists of a voltage-limiting overvoltage protector and an electromagnetic drive tripping mechanism. Its main structural feature is that it has a resettable tripping mechanism connected in series with the voltage-limiting overvoltage protector. This can solve the technical problems of unreliable and unreusable tripping actions achieved by overheating and melting thermal fuses or solder joints. Under normal conditions, the normally closed contacts of the electromagnetic drive tripping mechanism are in the closed state, which does not affect the normal operation of the voltage-limiting overvoltage protector or its protection under normal overvoltage conditions. When an overvoltage occurs, the pulse current flowing through the voltage-limiting varistor induces a current in the upper metal disk of the electromagnetic drive tripping mechanism that is opposite in direction to the current in the spiral conductor coil of the lower electromagnetic drive disk. This causes the upper metal disk of the lower electromagnetic drive mechanism to generate an electromagnetic repulsion force with the lower electromagnetic drive disk, thereby breaking the normally closed contacts of the electromagnetic drive tripping mechanism. This effectively suppresses the continuous effect of subsequent power frequency or DC arc on the voltage-limiting protector, preventing overheating and breakdown of the voltage-limiting overvoltage protector, and avoiding the influence and damage of subsequent power frequency or DC current on the voltage-limiting varistor. This extends the service life of the voltage-limiting overvoltage protection element and effectively improves both the safety factor and service life of the voltage-limiting overvoltage protection component.

[0019] The surface of the upper electrode of the normally closed contact is larger than that of the lower electrode, which is simple in structure. The upper electrode can be used as the moving electrode of the electromagnetic tripping mechanism, and the coil of the electromagnetic drive mechanism is directly and coaxially mounted on the outside of the lower electrode, which is opposite to the upper electrode.

[0020] This invention addresses the shortcomings of existing voltage-limiting overvoltage protection components with multilayer graphite gaps and controllable multilayer overvoltage protection gaps, and solves the technical problem of resettable tripping in voltage-limiting overvoltage protectors. It is particularly suitable for overvoltage protection in applications such as communications and even the power industry. Attached Figure Description

[0021] Figure 1 This is a structural block diagram of the voltage-limiting overvoltage protection component with a recoverable electromagnetic drive tripping mechanism according to the present invention.

[0022] Figure 2 This is a schematic diagram of the reversible electromagnetic drive tripping mechanism in this invention;

[0023] In the diagram: 1-overvoltage protection element with voltage limiting, 2-resettable electromagnetic drive tripping mechanism, 3-upper flange, 4-lower flange, 5-insulating shell, H21-upper electrode, L21-lower electrode, HC21-upper connection end, LC21-lower connection end, 21-normally closed contact, 22-retractable spring, 23-electromagnetic drive mechanism, 24-magnetic lines of force, QD23-1-upper metal disk, QD23-2-lower electromagnetic drive disk, EMQDXQ-spiral conductor coil. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0025] See Figure 1 The present invention relates to a voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism, which mainly consists of a voltage-limiting overvoltage protection element 1 and a resettable electromagnetic drive tripping mechanism 2. The voltage-limiting overvoltage protection element 1 is typically a varistor, an overvoltage protection element used in the communications field. The resettable electromagnetic drive tripping mechanism 2 consists of a pair of normally closed contacts 21, a retractable spring mechanism 22, and an electromagnetic drive mechanism 23. The normally closed contacts 21 are connected in series with the voltage-limiting overvoltage protection element 1.

[0026] like Figure 2 As shown, the resettable electromagnetic drive tripping mechanism 2 is installed in the insulating housing 5, which, together with the upper flange 3 and the lower flange 4, forms a closed unit. The upper electrode H21 of the normally closed contact 21 is a movable contact, and the surface of the upper electrode H21 of the normally closed contact 21 is larger than the surface of the lower electrode L21. The upper electrode H21 and the lower electrode L21 of the normally closed contact 21 are respectively led out to the upper connecting terminal HC21 and the lower connecting terminal LC21 through the upper flange 3 and the lower flange 4.

[0027] The lower end of the voltage-limiting overvoltage protection element 1 is electrically connected to the upper electrode H21 of the normally closed contact 21, forming a series structure of voltage-limiting overvoltage protection assembly. The upper end of the voltage-limiting overvoltage protection element 1 and the lower connection end LC21 of the normally closed contact 21 serve as the high voltage end HV and the low voltage end LV of the voltage-limiting overvoltage protection element, respectively.

[0028] The voltage-limiting overvoltage protection element 1 can be installed in a closed unit, or it can be installed together with the resettable electromagnetic drive tripping mechanism 2 in a closed unit. The preferred option is independent installation, and the size of the closed unit should preferably be selected to conform to the size of the electrical rail installation, and it can be designed as 1P, 2P or other sizes.

[0029] The retractable spring mechanism 22 is installed between the upper electrode H21 of the normally closed contact 21 and the upper flange 3, and is in a natural extension / retraction state under normal conditions. The lower end of the retractable spring 22 is fixedly installed on the upper surface of the upper electrode H21 of the normally closed contact 21 through insulation isolation, and the upper end of the retractable spring 22 is fixed to the upper flange 3.

[0030] The electromagnetic drive mechanism 23 mainly consists of an upper metal disk QD23-1 and a lower electromagnetic drive disk QD23-2. The lower electromagnetic drive disk QD23-2 of the electromagnetic drive mechanism 23 is an insulating disk engraved with circular or rectangular spiral lines. A spiral conductor coil EMQDXQ is fixed in the circular or rectangular spiral groove of the insulating disk. The current flowing through the spiral conductor coil EMQDXQ is taken from the pulse current signal of the voltage-limiting overvoltage protection element.

[0031] The upper metal disk QD23-1 of the electromagnetic drive mechanism 23 is mounted at the bottom of the upper electrode H21 of the normally closed contact 21. The lower electromagnetic drive disk QD23-2 is mounted below the upper metal disk QD23-1, opposite to it, and is in contact with it when not energized. The lower electromagnetic drive disk QD23-2 is fixed to the lower flange 4 of the sealed housing of the electromagnetic drive mechanism 23 by an insulating rod, or the lower electromagnetic drive disk QD23-2 is fixed to the insulating housing. The spiral conductor coil EMQDXQ is led out from the side of the insulating housing 5 for easy electrical connection with the lower end of the voltage-limiting overvoltage protection element 1.

[0032] Another simpler structure is that the upper metal disk QD23-1 of the electromagnetic drive mechanism 23 can be omitted and replaced by the upper electrode H21 of the normally closed contact 21.

[0033] See Figure 2 The present invention provides a schematic diagram of the structure of the recoverable electromagnetic drive tripping mechanism. The working principle of the electromagnetic drive mechanism is as follows:

[0034] Under normal conditions, the normally closed contacts of the electromagnetic drive tripping mechanism are in the closed state, which does not affect the normal working state and overvoltage protection state of the voltage-limiting overvoltage protection component.

[0035] When an overvoltage occurs, the voltage-limiting overvoltage protection element 1 changes from a high-resistance state to a low-resistance state, and the pulse current will flow through the voltage-limiting overvoltage protection element 1; at the same time, a pulse current is induced in the spiral conductive coil of the lower electromagnetic drive disk QD23-2 installed in the electromagnetic drive mechanism 23.

[0036] The pulse current in the spiral conductor coil EMQDXQ of the lower electromagnetic drive disk QD23-2 induces a current in the upper metal disk QD23-1 of the electromagnetic drive mechanism 23 that flows in the opposite direction to the spiral conductor coil EMQDXQ. As a result, an electromagnetic repulsion force is generated between the upper metal disk QD23-1 and the lower electromagnetic drive disk QD23-2, causing the upper metal disk QD23-1 to drive the telescopic spring 22 to move upward. The upper electrode H21 and the lower electrode L21 of the normally closed contact 21 are quickly separated. This can avoid the influence of the power frequency or DC follow-up current after overvoltage on the voltage-limiting overvoltage protection element 1, thereby extending the service life of the voltage-limiting overvoltage protection element 1. In particular, it can prevent the voltage-limiting overvoltage protection element 1 from thermal breakdown or even fire caused by the power frequency or DC follow-up current.

[0037] After the overvoltage, the pulse current in the spiral conductive coil of the lower electromagnetic drive disk QD23-2 disappears, and the electromagnetic repulsion between the upper metal disk QD23-1 and the lower electromagnetic drive disk QD23-2 also disappears. Under the drive of the retractable spring mechanism 22, the normally closed contact 21 returns to its original normally closed state.

[0038] The present invention has been described in detail with reference to the above embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific embodiments of the present invention without departing from the spirit and scope of the present invention, and such modifications or equivalent substitutions should be covered within the scope of the claims of this patent.

Claims

1. A voltage-limiting overvoltage protection component with a resettable electromagnetically driven tripping mechanism, characterized in that: It includes a voltage-limiting overvoltage protection element (1) and a resettable electromagnetic drive tripping mechanism (2); The resettable electromagnetic drive tripping mechanism (2) includes a pair of normally closed contacts (21), a retractable spring mechanism (22), and an electromagnetic drive mechanism (23) installed in the insulating housing (5). The upper and lower ends of the insulating housing (5) are closed by the upper flange (3) and the lower flange (4), respectively. The upper electrode (H21) of the normally closed contact (21) is a movable contact. The upper electrode (H21) and the lower electrode (L21) of the normally closed contact (21) are led out to the upper connection terminal (HC21) and the lower connection terminal (LC21) through the upper flange (3) and the lower flange (4), respectively. The lower end of the voltage limiting overvoltage protection element (1) is electrically connected to the upper connection terminal (HC21) of the normally closed contact (21) to form a series structure voltage limiting overvoltage protection assembly. The upper end of the voltage limiting overvoltage protection element (1) and the lower connection terminal (LC21) of the normally closed contact (21) serve as the high voltage terminal HV and the low voltage terminal LV of the voltage limiting overvoltage protection assembly, respectively. The telescopic spring mechanism (22) is installed between the upper electrode (H21) of the normally closed contact (21) and the upper flange (3), and is in a natural telescopic state under normal conditions. The lower end of the telescopic spring mechanism (22) is fixedly installed on the lower surface of the upper electrode (H21) of the normally closed contact (21) through insulation isolation, and the upper end of the telescopic spring mechanism (22) is fixed on the upper flange (3). The electromagnetic drive mechanism (23) includes an upper metal disk (QD23-1) and a lower electromagnetic drive disk (QD23-2). The upper metal disk (QD23-1) is fixed at the bottom of the upper electrode (H21) of the normally closed contact (21), and the lower electromagnetic drive disk (QD23-2) is fixed in the insulating shell (5) and is located below the upper metal disk (QD23-1) relative to it. When not energized, the two are in contact. A spiral conductor coil (EMQDXQ) is fixed in the lower electromagnetic drive disk (QD23-2). The current flowing through the spiral conductor coil (EMQDXQ) is taken from the pulse current signal of the voltage-limiting overvoltage protection element (1).

2. The voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism as described in claim 1, characterized in that: The lower electromagnetic drive disk (QD23-2) of the electromagnetic drive mechanism (23) is fixed to the lower flange (4) or to the insulating shell (5) by an insulating rod, and the spiral conductor coil (EMQDXQ) is led out from the side of the insulating shell (5).

3. The voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism as described in claim 2, characterized in that: The lower electromagnetic drive disk (QD23-2) of the electromagnetic drive mechanism (23) is an insulating disk engraved with circular or rectangular spiral lines, and a spiral conductor coil (EMQDXQ) is fixed in the circular or rectangular spiral groove of the insulating disk.

4. The voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism as described in claim 1, 2, or 3, characterized in that: The voltage-limiting overvoltage protection element (1) is a varistor.

5. The voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism as described in claim 4, characterized in that: The surface of the upper electrode (H21) of the normally closed contact (21) is larger than the surface of the lower electrode (L21).

6. The voltage-limiting overvoltage protection component with a resettable electromagnetic drive tripping mechanism as described in claim 4, characterized in that: The voltage-limiting overvoltage protection element (1) is installed alone in a closed unit, or together with the resettable electromagnetic drive tripping mechanism (2) in a closed unit, the size of which is 1P or 2P.

Images