Independent wire leg and thermal fuse

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By designing a avoidance groove on the contact surface of the independent wire pins, the problem of the residual pollutant in the existing hot fuses is solved, and the stable passage of large current is achieved, ensuring the stability of the current.

CN222672950UActive Publication Date: 2025-03-25A R ELECTRIC

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Patent Information

Application Number: CN202420449510.6
Authority / Receiving Office: CN · China
Patent Type: Utility models(China)
Current Assignee / Owner
Filing Date: 2024-03-05
Publication Date: 2025-03-25
Estimated Expiration: 2034-03-05

AI Technical Summary

Technical Problem

In existing thermal fuses, the convex arc-shaped contact surfaces of independent wire pins and star contact sheets are prone to residual pollutants, resulting in a decrease in contact area and a decrease in current passage, and the passage of large current cannot be guaranteed.

Method used

An independent wire pin is designed, with a concave contact groove provided with a concave contact groove, and the star contact sheet is electrically connected to the groove edge of the groove, forming an annular plane contact surface. Pollutants can fall into the groove along the inclined surface of the avoiding groove to avoid residual contact surfaces.

Benefits of technology

Through the design of the avoidance groove, the contact area between the independent pin and the star contact plate is ensured, the passage of large current is ensured, the resistance is increased, and the current stability is maintained.

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Abstract

The utility model discloses an independent wire pin and a thermal fuse, the contact surface of the independent wire pin is concavely provided with an avoiding groove, a star contact piece is electrically connected with the notch edge of the avoiding groove, and the contact surface of the independent wire pin and the star contact piece is an annular plane. According to the technical scheme of the utility model, the contact surface of the independent wire pin and the star contact piece is annularly arranged, and pollutants in the contact process of the independent wire pin and the star contact piece can be transferred into the avoiding groove, so that the condition that the contact surface is reduced due to residual pollutants is avoided, and the area of the contact surface of the independent wire pin and the star contact piece can be further ensured; and compared with a convex arc-shaped surface, the contact area is larger, and the area on the cross section is relatively increased, so that the relative resistance can be ensured to be smaller than that of the convex arc-shaped surface, the resistance value is ensured to be constant, and the passing of large current between the independent wire pin and the star contact piece can be ensured.

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Description

Technical Field

[0001] The utility model relates to the technical field of thermal fuses, in particular to an independent wire pin and a thermal fuse. Background Art

[0002] A fuse (also called a thermal fuse) is an electrical appliance that uses the heat generated by itself to melt the fuse and disconnect the circuit when the current exceeds the specified value.

[0003] The existing thermal fuse includes an independent wire pin and a star contact piece. The contact surface between the independent wire pin and the star contact piece is a convex arc surface. Since the contact surface of this setting method is a convex arc contact surface, contaminants are easily retained on the convex arc surface, which in turn affects the contact area. The resistance of the current flow is determined by the cross-sectional area of the carrier passing through. Since the reduction of the contact cross-sectional area will lead to an increase in resistance, the overall current passing through the thermal fuse is reduced, and the passage of large current cannot be guaranteed. Utility Model Content

[0004] The main purpose of the utility model is to provide an independent wire pin, aiming to ensure the contact surface area between the independent wire pin and the star contact piece, thereby ensuring the passage of a large current of the thermal fuse.

[0005] To achieve the above objectives, the utility model provides an independent wire pin, wherein the contact surface of the independent wire pin is concavely provided with an avoidance groove, the star contact piece is electrically connected to the notch edge of the avoidance groove, and the contact surface between the independent wire pin and the star contact piece is an annular plane.

[0006] Optionally, the cross-sectional shape of the avoidance groove in the depth direction is an arc;

[0007] Alternatively, the avoidance groove is hemispherical in shape.

[0008] Optionally, the center line of the avoidance groove and the axis line of the independent molding are located on the same straight line.

[0009] Optionally, the independent wire pin includes a contact portion and a connecting portion, an end surface of the contact portion away from the connecting portion is provided with an avoidance groove, the connecting portion is used to connect to an external cable, and a diameter of the contact portion is greater than a diameter of the connecting portion.

[0010] Optionally, the opening diameter of the avoidance groove accounts for 70% to 80% of the diameter of the contact portion.

[0011] Optionally, the central depth of the avoidance groove ranges from 0.3 mm to 0.4 mm.

[0012] The utility model also proposes a thermal fuse, comprising the independent wire pin, star contact piece and shell, hot melt component and circuit breaker spring as described above, the shell forming an installation cavity, one end of the installation cavity along the extension direction of the shell is an opening, the star contact piece is movably arranged in the installation cavity along the length direction of the installation cavity and contacts with the inner wall of the installation cavity, the end of the independent wire pin provided with the avoidance groove extends into the installation cavity along the opening and contacts with the star contact piece, the hot melt component is arranged at one end of the installation cavity away from the opening, the circuit breaker spring is sleeved on the independent wire pin, and one end of the circuit breaker spring abuts against the star contact piece to make the star contact piece abut against the hot melt component.

[0013] Optionally, the thermal fuse further includes a gasket, which is arranged between the star contact piece and the thermal fuse.

[0014] Optionally, the thermal fuse further comprises a cylindrical spring, one end of the cylindrical spring abuts against the star contact piece, and the other end abuts against the thermal melt piece, and the gasket is arranged between the cylindrical spring and the star contact piece and / or the thermal melt piece.

[0015] The technical solution of the utility model is to provide an avoidance groove on the contact surface between the independent wire pin and the star contact piece, and connect the star contact piece with the edge of the avoidance groove. In this way, the contact surface is arranged in a ring shape. The pollutants in the contact process between the independent wire pin and the star contact piece will be transferred to the avoidance groove, thereby avoiding the situation where the contact surface is reduced due to the residual pollutants. The contact area between the independent wire pin and the star contact piece can be guaranteed. Compared with the convex curved surface, it also has a larger contact area, and the area on the cross section is relatively increased. Therefore, the relative resistance can be guaranteed to be smaller than that of the convex curved surface, thereby ensuring that the resistance value is constant, and the passage of large current between the independent wire pin and the star contact piece can be guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0017] Figure 1 This is a schematic structural diagram of an embodiment of an independent molding foot of the utility model;

[0018] Figure 2 This is a front view structural diagram of the independent molding foot of the utility model;

[0019] Figure 3 It is a structural schematic diagram of an embodiment of the thermal fuse of the utility model.

[0020] Description of Figure Numbers:

[0021] Label name Label name 1 Independent line foot 10 Avoidance slot 1a Contact Department 1b Connection Department 100 Thermal fuse 2 Star Contact 3 case 4 Hot melt parts 5 Breaker spring 6 Barrel spring 7 Gasket

[0022] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0025] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0026] The utility model provides an independent molding 1.

[0027] In the embodiment of the present utility model, Figure 1 , Figure 2 As shown, the contact surface of the independent wire pin 1 is concavely provided with an avoidance groove 10, the star contact piece 2 is electrically connected to the notch edge of the avoidance groove 10, and the contact surface between the independent wire pin 1 and the star contact piece 2 is an annular plane.

[0028] The contact surface of the independent wire foot 1 is recessed with an avoidance groove 10. Compared with the case where the contact surface of the independent wire foot 1 is a convex arc-shaped surface, on the one hand, the size of the contact surface area can be ensured to remain unchanged, and the pollutants on the contact surface can fall into the avoidance groove 10 along the inclined surface of the avoidance groove 10 by gravity, thereby avoiding the situation where pollutants remain on the contact surface and affect the contact condition of the contact surface. It can be ensured that no pollutants remain on the contact surface, and the stability of the contact area size is guaranteed, thereby maintaining the stability of the flow resistance, ensuring the stability of the passing current, and ensuring the passage of large current; on the other hand, since it is guaranteed that large current can pass, arcing can be avoided, thereby improving the stability of current passage.

[0029] It can be understood that the contact surface is arranged in a ring shape, which can ensure a sufficiently large contact area between the independent wire pin 1 and the star contact piece 2. The relative resistance can be guaranteed to be smaller than that of the convex arc surface, ensuring a constant resistance value and ensuring the passage of large current between the independent wire pin 1 and the star contact piece 2.

[0030] The technical solution of the utility model is to provide an avoidance groove 10 on the contact surface between the independent wire pin 1 and the star contact piece 2, and connect the star contact piece 2 with the edge of the avoidance groove 10. In this way, the contact surface is arranged in a ring shape. The pollutants in the contact process between the independent wire pin 1 and the star contact piece 2 will be transferred to the avoidance groove 10, thereby avoiding the situation where the contact surface is reduced due to the residual pollutants, and thus the area of the contact surface between the independent wire pin 1 and the star contact piece 2 can be guaranteed. Compared with the convex curved surface, it also has a larger contact area, and the area located on the cross section is also relatively increased, so that the relative resistance can be guaranteed to be smaller than the case of the convex curved surface, thereby ensuring that the resistance value is constant, and the passage of large current between the independent wire pin 1 and the star contact piece 2 can be guaranteed.

[0031] In one embodiment of the present invention, Figure 1 , Figure 2 As shown, the cross-sectional shape of the avoidance groove 10 in the depth direction is an arc;

[0032] Alternatively, the avoidance groove 10 is in a hemispherical shape.

[0033] In one embodiment, the cross-sectional shape of the avoidance groove 10 in the depth direction is arc-shaped. When the longitudinal cross-sectional shape of the avoidance groove 10 is set to an arc, on the one hand, the arc-shaped groove is convenient for processing, reducing the processing cost, and on the other hand, the arc-shaped groove has high stability, maintaining the structural stability of the contact surface of the independent line foot 1, and the arc-shaped groove design has an inclined surface, so that the pollutants on the contact surface can fall into the avoidance groove 10 along the inclined surface of the avoidance groove 10 by gravity, avoiding the situation where pollutants remain on the contact surface, affecting the contact situation of the contact surface, and maintaining the size stability of the contact area. Similarly, the shape of the avoidance groove 10 is hemispherical, and the curvature of the groove reaches the optimal value, with high structural stability and use stability.

[0034] In one embodiment of the present invention, Figure 1 , Figure 2 As shown, the center line of the avoidance groove 10 and the axis of the independent molding 1 are located on the same straight line.

[0035] In this embodiment, the center line of the avoidance groove 10 is on the same straight line as the axis of the independent molding 1. Such a setting can ensure that the avoidance groove 10 is opened at the center position of the contact surface of the independent molding 1, and ensure that the connection position of the edge of the avoidance groove 10 and the star contact piece 2 are on the same straight line as the overall connection direction of the independent molding 1, thereby maintaining the stability of the connection between the independent molding 1 and the star contact piece 2, and further maintaining the effectiveness and stability of the contact surface and the star contact piece 2.

[0036] In one embodiment of the present invention, Figure 1 , Figure 2 As shown, the independent wire pin 1 includes a contact portion 1a and a connecting portion 1b. An avoidance groove 10 is provided on the end surface of the contact portion 1a away from the connecting portion 1b. The connecting portion 1b is used to connect to an external cable. The diameter of the contact portion 1a is larger than the diameter of the connecting portion 1b.

[0037] In this embodiment, the independent wire pin 1 includes a contact portion 1a and a connection portion 1b. The end surface of the contact portion 1a away from the connection portion 1b is provided with an avoidance groove 10. The connection portion 1b is used to connect to an external cable, and the diameter of the contact portion 1a is larger than the diameter of the connection portion 1b. The contact portion 1a is used to electrically connect to the star contact piece 2, and the connection portion 1b is used to connect to an external cable. The diameter of the contact portion 1a is larger than the diameter of the connection portion 1b. Such an arrangement can increase the contact area of the annular contact surface between the contact portion 1a and the star contact piece 2, thereby enabling the passage of large currents and meeting the requirements for the passage of large currents.

[0038] In one embodiment of the present invention, Figure 1 , Figure 2 As shown, the opening diameter of the avoidance groove 10 accounts for 70% to 80% of the diameter of the contact portion 1a.

[0039] In this embodiment, when the opening diameter of the avoidance groove 10 is between 70% and 80% of the diameter of the contact portion 1a, on the one hand, the contact area of the annular contact surface between the contact portion 1a and the star contact piece 2 can be guaranteed to achieve the passage of large current and meet the demand for the passage of large current. It will not affect the supporting effect of the independent wire pin 1 on the star contact piece 2, maintain the flatness of the contact surface of the contact portion 1a, and maintain the supporting stability of the independent wire pin 1 on the star contact piece 2.

[0040] In one embodiment of the present invention, Figure 1 , Figure 2As shown, the center depth of the avoidance groove 10 ranges from 0.3 mm to 0.4 mm.

[0041] In this embodiment, when the center depth range of the avoidance groove 10 is between 0.3mm and 0.4mm, on the one hand, the avoidance groove 10 can ensure the collection effect of pollutants in the contact process between the independent wire pin 1 and the star contact piece 2, and has an inclination that satisfies the sliding of pollutants, thereby ensuring that no pollutants remain on the contact surface, ensuring the stability of the size of the contact area, and then maintaining the stability of the flow resistance, ensuring the stability of the passing current, and ensuring the passage of large current.

[0042] The utility model also provides a thermal fuse 100, such as Figure 3 As shown, the thermal fuse 100 includes an independent wire pin 1, a star contact piece 2 and a shell 3, a hot melt component 4 and a circuit breaker spring 5. The shell 3 is formed with a mounting cavity, and one end of the mounting cavity along the extension direction of the shell 3 is an opening. The star contact piece 2 is movably arranged in the mounting cavity along the length direction of the mounting cavity and contacts with the inner wall of the mounting cavity. One end of the independent wire pin 1 provided with a avoidance groove 10 extends into the mounting cavity along the opening and contacts with the star contact piece 2. The hot melt component 4 is arranged at the end of the mounting cavity away from the opening. The circuit breaker spring 5 is sleeved on the independent wire pin 1, and one end of the circuit breaker spring 5 abuts against the star contact piece 2 so that the star contact piece 2 abuts against the hot melt component 4.

[0043] The specific structure of the thermal fuse 100 refers to the above embodiments. Since the thermal fuse 100 adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0044] In this embodiment, when the current passing through the thermal fuse 100 is within the normal range, the hot melt 4 is in a solid state, abutting between the contact surface of the star contact piece 2 and the independent wire pin 1, and compressing the circuit breaker spring 5, the star contact piece 2 and the independent wire pin 1 are in a connected state, and the other end of the star contact piece 2 is connected to the housing 3, and the current is transmitted to the outlet terminal through the housing 3. When the current passing through the thermal fuse 100 is too large, the hot melt 4 is melted by heat, and the circuit breaker spring 5 is restored to drive the star contact piece 2 to separate from the contact surface of the independent wire pin 1, the star contact piece 2 and the independent wire pin 1 are disconnected, and then the entire circuit is disconnected, protecting the circuit and electrical appliances.

[0045] In one embodiment of the present invention, Figure 3 As shown, the thermal fuse 100 further includes a gasket 7 , which is disposed between the star contact piece 2 and the thermal fuse 4 .

[0046] In this embodiment, the gasket 7 is arranged between the star contact piece 2 and the hot melt piece 4, which can protect the outer surface structure of the star contact piece 2 from being damaged, thereby improving the service life and working stability of the star contact piece 2.

[0047] In one embodiment of the present invention, Figure 3 As shown, the thermal fuse 100 also includes a cylindrical spring 6, one end of the cylindrical spring 6 abuts against the star contact piece 2, and the other end abuts against the thermal fuse 4, and a gasket 7 is arranged between the cylindrical spring 6 and the star contact piece 2 and / or the thermal fuse 4.

[0048] In this embodiment, one end of the cylindrical spring 6 abuts against the star contact piece 2, and the other end abuts against the hot melt piece 4, so that the star contact piece 2 can be kept in continuous contact with the contact surface of the independent wire pin 1 when the current of the thermal fuse 100 is within the normal range. The gasket 7 is arranged between the cylindrical spring 6 and the star contact piece 2 and / or the hot melt piece 4, which can protect the outer surface structure of the star contact piece 2 and the hot melt piece 4 from being damaged, thereby improving the service life and working stability of the star contact piece 2.

[0049] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An independent wire pin for a thermal fuse, the thermal fuse comprising a star contact (2), characterized in that: The contact surface of the independent wire pin is concavely provided with an avoidance groove (10), the star contact piece (2) is electrically connected to the notch edge of the avoidance groove (10), and the contact surface between the independent wire pin and the star contact piece (2) is an annular plane.

2. The independent molding as claimed in claim 1, characterized in that: The cross-sectional shape of the avoidance groove (10) in the depth direction is an arc; Alternatively, the avoidance groove (10) is in a hemispherical shape.

3. The independent molding as claimed in claim 2, characterized in that: The center line of the avoidance groove (10) and the axis line of the independent molding are located on the same straight line.

4. The independent molding as claimed in any one of claims 1 to 3, characterized in that: The independent wire pin comprises a contact portion (1a) and a connection portion (1b); an avoidance groove (10) is provided on an end surface of the contact portion (1a) away from the connection portion (1b); the connection portion (1b) is used to connect to an external cable; and the diameter of the contact portion (1a) is greater than the diameter of the connection portion (1b).

5. The independent molding as claimed in claim 4, characterized in that: The opening diameter of the avoidance groove accounts for 70% to 80% of the diameter of the contact portion (1a).

6. The independent molding as claimed in any one of claims 1 to 3, characterized in that: The central depth of the avoidance groove ranges from 0.3 mm to 0.4 mm.

7. A thermal fuse, characterized in that: The invention comprises an independent wire foot, a star contact piece (2) and a shell (3), a hot melt component (4) and a circuit breaker spring (5) as claimed in any one of claims 1 to 6, wherein the shell (3) is formed with a mounting cavity, and one end of the mounting cavity along the extension direction of the shell (3) is an opening, the star contact piece (2) is movably arranged in the mounting cavity along the length direction of the mounting cavity and contacts the inner wall of the mounting cavity, the end of the independent wire foot provided with the avoidance groove (10) extends into the mounting cavity along the opening and contacts the star contact piece (2), the hot melt component (4) is arranged at the end of the mounting cavity away from the opening, the circuit breaker spring (5) is sleeved on the independent wire foot, and one end of the circuit breaker spring (5) abuts against the star contact piece (2) so that the star contact piece (2) abuts against the hot melt component (4).

8. The thermal fuse according to claim 7, characterized in that The thermal fuse also includes a gasket (7), wherein the gasket (7) is arranged between the star contact piece (2) and the thermal fuse (4).

9. The thermal fuse according to claim 8, characterized in that The thermal fuse further comprises a cylindrical spring (6), one end of the cylindrical spring (6) abuts against the star contact piece (2), and the other end abuts against the thermal fuse (4), and the gasket (7) is arranged between the cylindrical spring (6) and the star contact piece (2) and / or the thermal fuse (4).