Surge protection device

Abstract

The utility model belongs to the technical field of circuit protection devices, and provides a surge protection device which is characterized in that a U-shaped groove is arranged at the end part of a separation sheet welded with the surface of a varistor element in the surge protection device, and a lead of the varistor element can pass through the U-shaped groove, so that the end part of the separation sheet is in full contact with the surface of the varistor element; therefore, the welding material can have a sufficient welding interval, and the welding strength is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit protection devices, in particular to a surge protection device. Background Art

[0002] Surge protection device is an electronic device that provides safety protection for various electronic equipment, instruments and communication lines. When a surge current or voltage suddenly occurs in an electrical circuit or communication line due to external interference, the surge protector can conduct and shunt in a very short time, thereby preventing the surge from damaging other devices in the circuit.

[0003] For example, the Chinese patent application with the number CN201610056635.2 discloses a surge protection device in which, under normal conditions, the terminal A of the voltage sensitive element (such as MOV) is welded to the pivot rod B by a low-temperature solder material, and the pivot rod B can rotate around the fulcrum and be electrically connected to the terminal (such as Figure 1 The thermal responsive switch is normally held by the pivot rod B through the slider. When the MOV is subjected to overvoltage and generates heat, the low-temperature solder material is melted or softened, and the pivot rod B is separated from the terminal A, causing the binding force of the pivot rod B on the slider of the thermal responsive switch to be released.

[0004] For another example, the Chinese patent application number CN202122373148.8 discloses a surge protection device including: a surge protection element, a low-temperature detachment spring, one end of which is fixed to the frame, and the other end is connected to the low-temperature flat area of ​​the varistor; a pre-detachment component connected to the low-temperature detachment spring, at least one area of ​​the pre-detachment component is connected to the other end of the low-temperature detachment spring, and can drive the low-temperature detachment spring to move; the force applied to the arc isolation plate by the bias force application component is transmitted to the pre-detachment component and the low-temperature detachment spring. By using the low-temperature flat surge protection element, the varistor is used to heat evenly and transfer heat quickly, so that the low-temperature point is quickly detached, and the reliability of heat transfer is increased.

[0005] As the application technology of surge protection devices expands, for example, in LED street lamps, base stations, etc., higher requirements are constantly being placed on the product performance and production process of surge protection devices. Utility Model Content

[0006] The utility model provides a surge protection device, in which the end of a breakaway piece welded to the surface of a varistor element is provided with a U-shaped groove, and the U-shaped groove allows the lead of the varistor element to pass therethrough, so that the end of the breakaway piece is in full contact with the surface of the varistor element, so that the welding material can have a sufficient welding interval, thereby improving the welding strength.

[0007] The utility model provides a surge protector, characterized by comprising:

[0008] A varistor element, wherein the varistor element has a predetermined rated voltage, and when the voltage applied to the voltage sensitive element exceeds the rated voltage, the temperature of the varistor element increases;

[0009] Lead wires, configured to connect the varistor element to a circuit to be protected;

[0010] A housing for mounting the varistor element and / or a circuit board electrically connected to the varistor element;

[0011] At least one elastic detachable spring piece, the detachable spring piece includes a welding portion connected to the surface of the varistor element, and a fixing portion fixed relative to the housing or circuit board; and the welding portion includes a U-shaped groove, the U-shaped groove allows the lead connected to the varistor element to pass through it, the outer side of the U-shaped groove abuts against the surface of the varistor element, and the space between the outer side of the U-shaped groove and the surface of the varistor element is filled with welding material.

[0012] In a preferred embodiment of the utility model, the opening of the U-shaped groove faces the surface of the varistor element, and a through hole is provided at the bottom of the U-shaped groove, and the welding material between the outer side of the U-shaped groove and the surface of the varistor element can seep out from the through hole during the welding process.

[0013] In a further preferred embodiment of the present invention, the number of through holes at the bottom of the U-shaped groove is greater than or equal to two.

[0014] In a preferred embodiment of the present invention, the U-shaped groove is inclined relative to the center of the welding portion, and is arranged on both sides of the center of the welding portion.

[0015] In a preferred embodiment of the present invention, the detachable spring piece further comprises a supporting portion located between the fixing portion and the welding portion, and a width of an end portion of the supporting portion connected to the welding portion is smaller than a width of the welding portion.

[0016] In a preferred embodiment of the utility model, when the welding portion in the detachable spring is welded to the surface of the varistor element, the portion between the welding portion in the detachable spring and the supporting portion in the detachable spring is deformed relative to a natural state; and when the temperature of the varistor element rises to a predetermined value, the welding portion in the detachable spring is automatically detached from the surface of the varistor element under the action of the deformation force.

[0017] In a preferred embodiment of the utility model, the number of the varistor elements is greater than or equal to 2, a corresponding detachable spring is provided on the surface of each varistor element, and each lead connected to the varistor element is welded on the circuit board in the shell.

[0018] Other features and advantages of the utility model will be described in the subsequent description, and partly become apparent from the description, or understood by implementing the technical solution of the utility model. The purpose and other advantages of the utility model can be achieved and obtained through the structures and / or processes specifically pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic structural diagram of a shell of a surge protector provided in an embodiment of the utility model.

[0020] Figure 2 A schematic diagram of a varistor element and a detached spring of a surge protector in a welding state provided in an embodiment of the utility model.

[0021] Figure 3 A side schematic diagram of a detachable spring piece of a surge protector provided in an embodiment of the utility model.

[0022] Figure 4 A schematic diagram of a varistor element and a detachable spring of a surge protector provided in an embodiment of the utility model in a detached state.

[0023] Reference numerals

[0024] 100-surge protector, 110-detachable spring, 120-varistor element,

[0025] 130-circuit board, 111-fixing part, 112-bending part,

[0026] 113-supporting portion, 114-welding portion, 115-first through hole,

[0027] 116 - second through hole, 117 - U row slot, 121 - first lead,

[0028] 122 - a second lead, 123 - a welding surface of a varistor element. DETAILED DESCRIPTION

[0029] The following will describe the implementation methods of the present invention in detail in combination with the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that these specific descriptions are only to make it easier and clearer for ordinary technicians in this field to understand the present invention, rather than a restrictive interpretation of the present invention; and as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0030] The technical solution of the utility model is described in detail below through the accompanying drawings and specific embodiments:

[0031] In the surge protection device provided by the utility model: the end of the breakaway piece welded to the surface of the varistor element is provided with a U-shaped groove, and the U-shaped groove allows the lead of the varistor element to pass through it, so that the end of the breakaway piece is in full contact with the surface of the varistor element, so that the welding material can have a sufficient welding area, thereby improving the welding strength. It should be noted that the "U-shaped groove" provided in this embodiment is similar to the U-line, and its purpose is to allow the lead of the varistor element to pass through it, and it is not strictly limited to the shape of the letter U. For example, on the basis of the V-line, some chamfers are made on the bottom; for another example, the grooves on both sides of the center line of the "U-shaped groove" are not strictly symmetrically designed. These different variations all fall within the protection scope of the technical solution provided by the utility model.

[0032] Specifically, Figure 1-Figure 4 As shown, this embodiment provides a surge protector 100, and the surge protector 100 includes:

[0033] The varistor element 120 has a predetermined rated voltage. When the voltage applied to the voltage sensitive element exceeds the rated voltage, the temperature of the varistor element increases. The rated voltage mentioned here is for the convenience of expression. On the one hand, it means that when the voltage in the circuit exceeds the rated value, the varistor element 120 can disconnect the circuit to be protected. On the other hand, when some current exceeds the predetermined value, since there is a resistor in the protection circuit, the circuit can also be converted to exceed the predetermined corresponding voltage. That is, the varistor element 120 can be a voltage sensitive device or a current sensitive device.

[0034] The first lead 121 and the second lead 122 are respectively arranged on the surface (for example, two opposite sides) of the varistor element 120, and the varistor element 120 is connected to the circuit to be protected through the two leads. The circuit to be protected can be a circuit inside the surge protector 100, or it can be the entire external circuit where the surge protector 100 is located, for example, an LED street lamp, a base station or a household power grid circuit.

[0035] The housing is used to mount the varistor element 120 and / or a circuit board to which the varistor element 120 is electrically connected; that is, the varistor element 120 may be directly fixed inside the housing, or may be indirectly fixed inside the housing through one or more circuit boards.

[0036] At least one elastic detachable spring 110, the detachable spring 110 includes a welding portion 114 connected to the surface of the varistor element (for example, the varistor element welding surface 123), and a fixing portion 111 fixed relative to the housing or circuit board; that is, one end of the detachable spring 110 can be directly fixed to the housing or welded to a circuit board inside the housing, and the other end of the detachable spring 110 is welded to the varistor element welding surface 123, by providing an elastically deformable connecting portion (or supporting portion). Figure 2 For example, the fixing portion 111 of the detachable spring piece 110 is in the shape of an "I" character, and both ends of the "I" character are welded to the circuit board 130 inside the shell, so that the spring piece can be kept stably fixed. A bending portion 112 is provided at the end of the fixing portion 111, and the bending portion 112 is convenient for adjusting the deformation force of the detachable spring piece 110. The supporting portion 113 connected to the bending portion 112 extends toward the welding surface 123 of the varistor element, and a welding portion 114 is connected to one side of the supporting portion 113.

[0037] like Figure 2 , Figure 4 As shown, the welding portion 114 includes a U-shaped groove 117. The U-shaped groove 117 allows the second lead 122 connected to the varistor element 120 to pass through the inside of the U-shaped groove 117. The outside of the U-shaped groove 117 (for example, Figure 2 , Figure 4 The two sides of the U-shaped groove 117 are in contact with the surface of the varistor element 120, and welding material is filled between the outside of the U-shaped groove 117 and the surface of the varistor element 120; so that the welding material can have a sufficient welding area to improve the welding strength.

[0038] like Figure 2 , Figure 4 As shown, the opening of the U-shaped groove 117 faces the surface of the varistor element 120, and a through hole (e.g., a first through hole 115, a second through hole 116) is provided at the bottom of the U-shaped groove, and the welding material between the outer side of the U-shaped groove 117 and the surface of the varistor element 120 can seep out from the through hole during the welding process. It is further ensured that the detachment spring 110 (also called the detachment sheet) and the lead (e.g., the second lead 122 made of copper wire) and the surface of the varistor element 120 are fully welded. In a preferred embodiment, the number of through holes at the bottom of the U-shaped groove is greater than or equal to two.

[0039] like Figure 2 , Figure 3 , Figure 4 As shown, the U-shaped groove 117 is inclined relative to the center of the welding portion 114 and is arranged on both sides of the center of the welding portion 114; this is more conducive to the arrangement of the leads of the varistor element 120 and is also more convenient for welding.

[0040] like Figure 2 , Figure 3 , Figure 4 As shown, in a preferred implementation manner of this embodiment, the detachment spring piece 110 also includes a supporting portion 113 located between the fixing portion 111 and the welding portion 114, and the width of the end portion of the supporting portion 113 connected to the welding portion 114 is smaller than the width of the welding portion 114, that is, the width of the supporting portion 113 on the side close to the welding portion 114 is smaller than the width of the welding portion 114. In this way, without increasing the carbon sheet material, the welding area can be larger, which is conducive to facilitating welding operations and welding strength.

[0041] like Figure 2 , Figure 4 As shown, when the welding portion 114 in the detachable spring piece 110 is welded to the surface of the varistor element 120, the portion between the welding portion 114 in the detachable spring piece 110 and the supporting portion 113 in the detachable spring piece 110 is deformed relative to the natural state; and when the temperature of the varistor element 120 rises to a predetermined value, the varistor element 120 heats up, the welding portion 114 is welded and disconnected from the surface of the varistor element 120, and the welding portion 114 in the detachable spring piece 110 is automatically detached from the surface of the varistor element 120 under the action of the deformation force.

[0042] By adopting the technical solution provided in this embodiment, a U-shaped groove 117 is provided at the end of the detachment spring 110 to avoid the protruding position of the lead on the surface of the varistor element 120, so that the two side surfaces of the U-shaped groove 117 can fully contact the surface of the varistor element 120. A low-temperature alloy material (for example, a welding material without the need for multiple welding materials) can be used. The melting point of the low-temperature alloy is not easy to change, the heat transfer is fast, and the fault detachment is fast.

[0043] like Figure 2 , Figure 4 As shown, the number of varistor elements 120 is greater than or equal to 2, and the surface of each varistor element 120 is respectively provided with a corresponding release spring 110, and each lead connected to the varistor element 120 is respectively welded on the circuit board 130 in the housing. In this way, it is convenient to adjust according to actual conditions, such as the power safety parameters of the circuit to be protected, in combination with the above technical solution, to increase the market application of the surge protector provided by this embodiment.

[0044] Finally, it should be noted that the above description is only the best embodiment of the utility model, and does not limit the utility model in any form. Any technician familiar with the field can make many possible changes and simple replacements to the technical solution of the utility model by using the above disclosed methods and technical contents without departing from the scope of the technical solution of the utility model, and these are all within the scope of protection of the technical solution of the utility model.

Claims

1. A surge protection device, characterized in that: include: A varistor element, wherein the varistor element has a predetermined rated voltage, and when the voltage applied to the varistor element exceeds the rated voltage, the temperature of the varistor element increases; Lead wires, configured to connect the varistor element to a circuit to be protected; A housing for mounting the varistor element and / or a circuit board electrically connected to the varistor element; At least one elastic detachable spring piece, the detachable spring piece includes a welding portion connected to the surface of the varistor element, and a fixing portion fixed relative to the housing or circuit board; and the welding portion includes a U-shaped groove, the U-shaped groove allows the lead connected to the varistor element to pass through it, the outer side of the U-shaped groove abuts against the surface of the varistor element, and the space between the outer side of the U-shaped groove and the surface of the varistor element is filled with welding material.

2. The surge protection device according to claim 1, characterized in that: The opening of the U-shaped groove faces the surface of the varistor element, and a through hole is provided at the bottom of the U-shaped groove, and the welding material between the outer side of the U-shaped groove and the surface of the varistor element can seep out from the through hole during the welding process.

3. The surge protection device according to claim 2, characterized in that: The number of through holes at the bottom of the U-shaped groove is greater than or equal to two.

4. The surge protection device according to claim 1, characterized in that: The U-shaped grooves are inclined relative to the center of the welding portion and are arranged on both sides of the center of the welding portion.

5. The surge protection device according to claim 1, characterized in that: The detachable spring piece further includes a supporting portion located between the fixing portion and the welding portion, and a width of an end portion of the supporting portion connected to the welding portion is smaller than a width of the welding portion.

6. The surge protection device according to claim 1, characterized in that: When the welding part in the detachable spring piece is welded to the surface of the varistor element, the portion between the welding part in the detachable spring piece and the supporting part in the detachable spring piece is deformed relative to the natural state; and when the temperature of the varistor element rises to a predetermined value, the welding part in the detachable spring piece is automatically detached from the surface of the varistor element under the action of the deformation force.

7. The surge protection device according to claim 1, characterized in that: The number of the varistor elements is greater than or equal to 2, a corresponding detachable spring is provided on the surface of each varistor element, and each lead connected to the varistor element is welded on the circuit board in the shell.

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