Bimetal sheet thermal protector

Abstract

The utility model belongs to the technical field of circuit protection, and particularly relates to a bimetallic strip thermal protector. Comprising a bottom plate, the upper end face of the bottom plate is provided with a bimetallic strip body, the upper end face of the bimetallic strip body is provided with a movable contact piece, the lower end face of the movable contact piece is fixedly provided with a movable contact piece, a static contact piece is arranged below the movable contact piece, and the movable contact piece is attached to the upper end face of the static contact piece. An elastic disconnection assembly is arranged on the upper end face of the bottom plate, and one end of the bimetallic strip body is inserted into the elastic disconnection assembly. According to the utility model, through the arrangement of the elastic disconnection assembly, the force generated when the bimetallic strip body is heated and bent can be converted into the elastic force that the disconnection push rod pushes the movable contact piece away from the static contact piece upwards, so that the speed that the movable contact piece and the static contact piece are separated and powered off due to the slow heating and bending speed of the bimetallic strip body can be shortened; therefore, the sensitivity of the thermal protection function of the device is effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of circuit protection technology, specifically a bimetallic strip thermal protector. Background Technology

[0002] A bimetallic strip thermal protector, also known as a bimetallic thermostat, is a commonly used device for circuit protection. It works by bonding two metal strips with different coefficients of thermal expansion together to form a double-layer structure. When the heating element exceeds a set temperature, the difference in thermal expansion coefficients causes the bimetallic strip to bend or twist, thus disconnecting the circuit through a connector to achieve overload protection. Simultaneously, when the circuit cools down, the bimetallic strip returns to its original state, reconnecting the circuit. This type of thermal protector has advantages such as fast response and high reliability, and is widely used in household appliances, automobiles, air conditioners, and other fields.

[0003] For example, application number 202321410462.1 describes a bimetallic strip thermal protector. In the initial state, the moving contact and the stationary contact are in contact. When the temperature at the location of the thermal protector rises to a predetermined temperature protection value, the concave surface of the bimetallic strip flips upward, pushing the concave surface of the moving contact to flip upward, separating the contact between the moving contact and the stationary contact, and breaking the circuit to protect the corresponding electrical equipment from overheating damage.

[0004] It has the following disadvantages:

[0005] Because metal deforms relatively slowly when heated, and bimetallic strips have a relatively limited reversal speed when heated, the slow reversal speed of bimetallic strips can lead to a slower separation speed between the moving contact and the stationary contact when the temperature of the thermal protector rises to the predetermined protection value, resulting in poor sensitivity of the device's thermal protection function.

[0006] Therefore, we propose a bimetallic strip thermal protector to solve the above problems. Utility Model Content

[0007] (a) Technical problems to be solved

[0008] To address the shortcomings of existing technologies, this invention provides a bimetallic strip thermal protector that solves the problems mentioned in the background section.

[0009] (II) Technical Solution

[0010] To achieve the above objectives, this utility model specifically adopts the following technical solution:

[0011] A bimetallic strip thermal protector includes a base plate, a bimetallic strip body disposed on the upper surface of the base plate, a movable contact piece disposed on the upper surface of the bimetallic strip body, a movable contact piece fixedly disposed on the lower surface of the movable contact piece, a stationary contact piece disposed below the movable contact piece, the movable contact piece being attached to the upper surface of the stationary contact piece, and an elastic disconnection assembly disposed on the upper surface of the base plate, one end of the bimetallic strip body being inserted into the elastic disconnection assembly, the elastic disconnection assembly being used to quickly spring the movable contact piece that triggers the thermal protection function away from the stationary contact piece.

[0012] Furthermore, the elastic disconnection assembly includes a fixed cylinder fixedly mounted on the base plate, a compression spring fixedly mounted on the bottom inner side of the fixed cylinder, a disconnection top rod inserted into the fixed cylinder, and one end of the compression spring being fixedly connected to the disconnection top rod inserted into the fixed cylinder.

[0013] Furthermore, the fixed cylinder has an opening, the disconnect rod has a limiting groove, the limiting groove and the opening are positioned to correspond to each other, and one end of the bimetallic strip body passes through the opening and is inserted into the limiting groove on the disconnect rod.

[0014] Furthermore, a guide groove is provided on the disconnection top rod, the guide groove is located below the limiting groove, and the guide groove communicates with the limiting groove.

[0015] Furthermore, a plurality of connecting screws are provided above the movable contact piece, and one end of the connecting screw passes through the base plate, the bimetallic strip body, and the movable contact piece in sequence and is connected by a threaded cap.

[0016] Furthermore, a support base is fixedly provided on the upper end surface of the base plate, and the stationary contact piece is provided on the upper end surface of the support base.

[0017] Furthermore, the front and rear side walls of the base plate are provided with a limiting frame, the inner top of the limiting frame is abutted on the upper end face of the stationary contact piece, a plurality of first positioning holes are sequentially opened on the limiting frame, and a plurality of second positioning holes are opened on both the front and rear side walls of the base plate, and the plurality of first positioning holes on the limiting frame correspond to the plurality of second positioning holes on the base plate in pairs.

[0018] (III) Beneficial Effects

[0019] Compared with the prior art, this utility model provides a bimetallic strip thermal protector with the following advantages:

[0020] This invention, through the setting of the elastic disconnect component, can convert the force generated by the heat bending of the bimetallic strip body into the elastic force that pushes the moving contact piece away from the stationary contact piece by the disconnect top rod. This can shorten the time when the moving contact piece separates from the stationary contact piece due to the slow heat bending speed of the bimetallic strip body, thereby effectively improving the sensitivity of the device's thermal protection function. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0022] Figure 2 This is an exploded view of the present invention;

[0023] Figure 3 This is a perspective view of the elastic disconnection component of this utility model;

[0024] Figure 4 This is a cross-sectional view of the elastic disconnection component of this utility model;

[0025] Figure 5 This is a disassembled view of the base plate and the limiting frame of this utility model.

[0026] In the figure: 1. Base plate; 2. Bimetallic strip body; 3. Moving contact piece; 4. Moving contact piece; 5. Stationary contact piece; 6. Elastic disconnect assembly; 601. Fixed cylinder; 602. Compression spring; 603. Disconnect top rod; 604. Opening; 605. Limiting groove; 606. Guide groove; 7. Connecting screw; 8. Support base; 9. Limiting frame; 10. First positioning hole. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] Example

[0029] like Figure 1-5As shown, an embodiment of this utility model discloses a bimetallic strip thermal protector, including a base plate 1. A bimetallic strip body 2 is disposed on the upper surface of the base plate 1. A movable contact piece 3 is disposed on the upper surface of the bimetallic strip body 2. A movable contact piece 4 is fixedly disposed on the lower surface of the movable contact piece 3. A stationary contact piece 5 is disposed below the movable contact piece 3. The movable contact piece 4 is attached to the upper surface of the stationary contact piece 5. An elastic disconnection component 6 is disposed on the upper surface of the base plate 1. One end of the bimetallic strip body 2 is inserted into the elastic disconnection component 6. The elastic disconnection component 6 is used to quickly spring the movable contact piece 4, which triggers the thermal protection function, away from the stationary contact piece 5.

[0030] like Figure 3 and Figure 4 As shown, the elastic disconnect assembly 6 includes a fixed cylinder 601 fixedly mounted on the base plate 1. A compression spring 602 is fixedly mounted on the bottom inner side of the fixed cylinder 601. A disconnect rod 603 is inserted into the fixed cylinder 601, and one end of the compression spring 602 is fixedly connected to the disconnect rod 603 inserted into the fixed cylinder 601. An opening 604 is provided on the fixed cylinder 601, and a limiting groove 605 is provided on the disconnect rod 603. The limiting groove 605 and the opening 604 are positioned corresponding to each other, and one end of the bimetallic strip body 2 passes through the opening 604 and is inserted into the limiting groove 605 on the disconnect rod 603. A guide groove 606 is provided on the disconnect rod 603, and the guide groove 606 is located below the limiting groove 605 and communicates with the limiting groove 605.

[0031] By setting the elastic disconnect component 6, the force generated by the heat bending of the bimetallic strip body 2 can be converted into the elastic force of the disconnect top rod 603 pushing the moving contact piece 4 away from the stationary contact piece 5. This can shorten the time when the moving contact piece 4 separates from the stationary contact piece 5 due to the slow heat bending speed of the bimetallic strip body 2, thereby effectively improving the sensitivity of the device's thermal protection function.

[0032] Multiple connecting screws 7 are provided above the movable contact piece 3. One end of each connecting screw 7 passes through the base plate 1, the bimetallic strip body 2, and the movable contact piece 3 in sequence and is connected by a threaded cap. A support base 8 is fixedly provided on the upper end surface of the base plate 1, and the stationary contact piece 5 is provided on the upper end surface of the support base 8.

[0033] The connecting screws 7 and threaded caps are used to fix the base plate 1, bimetallic strip body 2, and moving contact piece 3 together, and make it easy to disassemble and install the base plate 1, bimetallic strip body 2, and moving contact piece 3. The support base 8 serves to support the stationary contact piece 5.

[0034] Limiting frames 9 are provided on the front and rear side walls of the base plate 1. The inner top of the limiting frame 9 rests on the upper end face of the stationary contact piece 5. Multiple first positioning holes 10 are sequentially formed on the limiting frame 9, and multiple second positioning holes are formed on both the front and rear side walls of the base plate 1. The multiple first positioning holes 10 on the limiting frame 9 correspond to the multiple second positioning holes on the base plate 1 in pairs. The limiting frame 9 is used to restrict the position of the stationary contact piece 5 on the support base 8.

[0035] The first positioning hole 10 and the second positioning hole allow the limit frame 9 to be fixedly connected to the base plate 1 with screws. This allows the limit frame 9 to be disassembled and replaced, thus saving the maintenance cost of replacing the entire device if the limit frame 9 is damaged.

[0036] The working principle of this practical application is as follows:

[0037] When the temperature at the location of the thermal protector rises to the predetermined temperature protection value, the bimetallic strip body 2 is bent by heat. During the bending process, the bimetallic strip body 2, which is inserted into the limiting groove 605, moves out of the limiting groove 605. When one end of the bimetallic strip body 2 moves out of the limiting groove 605, the compression spring 602 pushes the disconnect rod 603 upward through its own elastic potential energy. The upward movement of the disconnect rod 603 will lift the moving contact 3. When the moving contact 3 is lifted, the moving contact piece 4 on the moving contact piece 3 separates from the stationary contact piece 5. At this time, the circuit is broken to protect the corresponding electrical equipment from overheating damage. When the temperature at the location of the thermal protector drops to a certain value, the circuit will be restored. When the value is set, the bimetallic strip body 2 returns to its original state. During the recovery process, one end of the bimetallic strip body 2 moves along the guide groove 606 on the disconnection rod 603 to the limiting groove 605 on the disconnection rod 603. When one end of the bimetallic strip body 2 moves along the guide groove 606 to the limiting groove 605 on the disconnection rod 603, the bimetallic strip body 2 pushes the disconnection rod 603 towards the bottom end of the fixed cylinder 601. The movement of the disconnection rod 603 compresses the compression spring 602 inside the fixed cylinder 601. When one end of the bimetallic strip body 2 is pressed against the limiting groove 605 on the disconnection rod 603, the bimetallic strip body 2 can return to its initial state.

[0038] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A bimetallic strip thermal protector, comprising a base plate (1), characterized in that: The upper surface of the base plate (1) is provided with a bimetallic strip body (2), the upper surface of the bimetallic strip body (2) is provided with a movable contact piece (3), the lower surface of the movable contact piece (3) is fixedly provided with a movable contact piece (4), the lower part of the movable contact piece (3) is provided with a stationary contact piece (5), the movable contact piece (4) is attached to the upper surface of the stationary contact piece (5), the upper surface of the base plate (1) is provided with an elastic disconnection assembly (6), one end of the bimetallic strip body (2) is inserted into the elastic disconnection assembly (6), and the elastic disconnection assembly (6) is used to quickly pop the movable contact piece (4) that triggers the thermal protection function away from the stationary contact piece (5).

2. The bimetallic strip thermal protector according to claim 1, characterized in that: The elastic disconnection assembly (6) includes a fixed cylinder (601) fixedly mounted on the base plate (1). A compression spring (602) is fixedly mounted on the bottom inner side of the fixed cylinder (601). A disconnection top rod (603) is inserted into the fixed cylinder (601). One end of the compression spring (602) is fixedly connected to the disconnection top rod (603) inserted into the fixed cylinder (601).

3. A bimetallic strip thermal protector according to claim 2, characterized in that: An opening (604) is provided on the fixed cylinder (601), and a limiting groove (605) is provided on the disconnecting top rod (603). The limiting groove (605) and the opening (604) are positioned to correspond to each other, and one end of the bimetallic strip body (2) passes through the opening (604) and is inserted into the limiting groove (605) on the disconnecting top rod (603).

4. A bimetallic strip thermal protector according to claim 3, characterized in that: The disconnect top rod (603) is provided with a guide groove (606), which is located below the limiting groove (605) and is connected to the limiting groove (605).

5. A bimetallic strip thermal protector according to claim 1, characterized in that: Multiple connecting screws (7) are provided above the movable contact piece (3). One end of the connecting screw (7) passes through the base plate (1), the bimetallic sheet body (2), and the movable contact piece (3) in sequence and is connected by a threaded cap.

6. A bimetallic strip thermal protector according to claim 1, characterized in that: A support base (8) is fixedly provided on the upper end surface of the base plate (1), and the static contact piece (5) is provided on the upper end surface of the support base (8).

7. A bimetallic strip thermal protector according to claim 1, characterized in that: The front and rear side walls of the base plate (1) are provided with a limiting frame (9). The inner top of the limiting frame (9) is abutted on the upper end face of the stationary contact piece (5). A plurality of first positioning holes (10) are sequentially opened on the limiting frame (9). A plurality of second positioning holes are opened on both the front and rear side walls of the base plate (1). The plurality of first positioning holes (10) on the limiting frame (9) correspond to the plurality of second positioning holes on the base plate (1) in pairs.

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