Current overload protector

Abstract

The utility model discloses a current overload protector, which comprises a shell and a cover plate hooked and fixed at the side part of the shell, an installation cavity is arranged in the shell, an overload protection unit and a terminal unit electrically matched with the overload protection unit are arranged in the installation cavity, and a switch unit used for pushing the overload protection unit to be bent and electrified is also arranged in the installation cavity. The switch unit is arranged at the upper part of the overload protection unit, and the terminal unit is arranged at the lower part of the overload protection unit; one end of the overload protection unit abuts against the inner wall of the installation cavity, and the other end of the overload protection unit is fixedly connected with the terminal unit. The structure design is reasonable, one end of the bimetallic strip is in contact connection with the inner wall of the installation cavity, the other end of the bimetallic strip is fixedly connected with the installation column in an inserted mode, the connection mode is simple, and abnormal work of the bimetallic strip caused by infirm fixation in the installation and fixation process of workers is avoided. And disconnection and connection of the moving contact and the static contact under normal work are ensured.

Description

Technical Field

[0001] The utility model relates to the field of overload protectors, in particular to a current overload protector. Background Art

[0002] During the use of many electrical devices, there may be excessive line current caused by overloading, short circuit of the line, or aging of the equipment insulation. If the device continues to be used when the line current is excessive, it will cause overheating or even burning of the device. If the line is under the action of strong electricity for a long time, the insulation performance of the line will also be reduced or the line will be burned.

[0003] Therefore, an overload protector is generally connected in series to the electrical device. When an abnormal situation occurs during the operation of the electrical device, resulting in excessive current, the excessive current will cause the temperature of the line to rise. The bimetallic strip in the overload protector will deform due to heat, and the deformation action will cause the moving contact of the bimetallic strip to separate from the static contact, thereby disconnecting the loop of the device and preventing the electrical device from operating under excessive current for a long time, achieving the purpose of protecting the electrical device.

[0004] The fixing methods at both ends of the bimetallic strip in the existing overload protectors are usually complex. Due to the insecure fixed connection, or the negligence of workers during installation and fixation, or the quality problems of the fixing parts themselves, during the deformation process of the bimetallic strip, the moving contact and the static contact cannot be completely disconnected or closed, resulting in problems such as overheating of the electrical device or weak electrical connection of the circuit, affecting the use of the electrical device. Summary of the Utility Model

[0005] The technical problem to be solved by the utility model is to provide a current overload protector in view of the current situation of the prior art.

[0006] The technical solution adopted by the utility model to solve the above technical problems is: a current overload protector, including a housing and a cover plate hooked and fixed to the side of the housing. An installation cavity is provided in the housing. An overload protection unit and a terminal unit electrically cooperating with the overload protection unit are provided in the installation cavity. A switch unit for pushing the overload protection unit to bend and conduct electricity is also provided in the installation cavity. The switch unit is arranged above the overload protection unit, and the terminal unit is arranged below the overload protection unit. One end of the overload protection unit is in contact connection with the inner wall of the installation cavity, and the other end of the overload protection unit is fixedly connected to the terminal unit.

[0007] Preferably, the terminal unit includes a static terminal and a moving terminal. Both the static terminal and the moving terminal are bent. The static terminal and the moving terminal are both snap-connected in the installation cavity, and the bottom ends of the static terminal and the moving terminal both extend to the outside of the housing.

[0008] Preferably, one end of the static terminal arranged in the installation cavity is inserted with a static contact electrically cooperating with the overload protection unit, and one end of the moving terminal arranged in the installation cavity is provided with an installation post for fixing the overload protection unit.

[0009] Preferably, the overload protection unit includes a bimetal sheet for controlling the disconnection of current overload. A moving contact electrically cooperating with the static contact is inserted on the bimetal sheet. One end of the bimetal sheet is in contact connection with the inner wall of the installation cavity, and the other end of the bimetal sheet is inserted and fixedly connected with the installation post.

[0010] Preferably, the switch unit includes a button. The button is movably arranged on the outer shell. The top end of the button extends to the outside of the outer shell, and the bottom end of the button is arranged in the installation cavity. The bottom end of the button is in contact cooperation with the moving contact.

[0011] Preferably, a spring for resetting the button is sleeved at a position near the bottom end of the button. One end of the spring is in contact connection with the inner wall of the installation cavity, and the other end of the spring is in contact connection with the button.

[0012] Preferably, the button is integrally formed.

[0013] Preferably, the cover plate is fixedly connected to the side of the outer shell by riveting nails. One ends of the static terminal and the moving terminal arranged outside the installation cavity are both bent in an "L" shape.

[0014] Preferably, a pin is inserted and split at the bottom of the button. The pin is a heat-resistant metal block structure.

[0015] Compared with the prior art, the advantages of the present utility model are as follows: by connecting one end of the bimetal sheet in contact with the inner wall of the installation cavity and inserting and fixedly connecting the other end of the bimetal sheet with the installation post, the connection method is simple, avoiding the abnormal operation of the bimetal sheet caused by insecure fixation during the installation and fixation process by workers, and ensuring the disconnection and connection of the moving contact and the static contact under normal working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural view of the present utility model;

[0017] Figure 2 is a schematic internal structural view of the present utility model;

[0018] Figure 3 is an exploded structural view of the present utility model;

[0019] Figure 4 is a schematic structural view of the present utility model;

[0020] Figure 5 is a schematic structural view of the present utility model.

[0021] Reference numerals: 1, outer shell; 2, cover plate; 3, installation cavity; 4, static terminal; 5, moving terminal; 6, static contact; 7, mounting post; 8, bimetallic strip; 9, moving contact; 10, button; 11, spring; 12, riveting nail; 13, pin. Detailed implementation

[0022] The following will disclose multiple embodiments of the present utility model with diagrams. For the sake of clear illustration, many practical details will be described together in the following narrative. However, it should be understood that these practical details are not used to limit the present utility model. That is to say, in some embodiments of the present utility model, these practical details are unnecessary. In addition, for the purpose of simplifying the diagrams, some conventional structures and components will be shown in a simple schematic manner in the diagrams.

[0023] It should be noted that all directional indications in the embodiments of the present utility model, such as up, down, left, right, front, back... are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If this specific posture changes, then the directional indications will also change accordingly.

[0024] Moreover, in addition to being able to represent the orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "up" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present utility model can be understood according to the specific situation.

[0025] In addition, the terms "installation", "setting", "provided with", "connection", "connected", "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there is an internal connection between two devices, components or parts. The connection methods involved in this article are prior arts and have not been improved, and all belong to the common knowledge of those skilled in the art. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to the specific situation.

[0026] In addition, in the present utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present utility model. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. 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 this 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 present utility model. Example 1

[0027] like Figures 1 to 3 As shown, the utility model provides a current overload protector, including a shell 1 and a cover plate 2 hooked and fixed to the side of the shell 1, and a mounting cavity 3 is provided in the shell 1; specifically, an overload protection unit and a terminal unit electrically matched with the overload protection unit are provided in the mounting cavity 3, and a switch unit for pushing the overload protection unit to bend and energize is also provided in the mounting cavity 3, the switch unit is movably arranged at the upper part of the overload protection unit, and the terminal unit is arranged at the lower part of the overload protection unit; one end of the overload protection unit is in contact with the inner wall of the mounting cavity 3, and the other end of the overload protection unit is fixedly connected to the terminal unit.

[0028] The terminal unit includes a static terminal 4 and a dynamic terminal 5, and both the static terminal 4 and the dynamic terminal 5 are bent; specifically, the static terminal 4 and the dynamic terminal 5 are snap-connected in the installation cavity 3, and the bottom ends of the static terminal 4 and the dynamic terminal 5 extend to the outside of the housing 1.

[0029] One end of the static terminal 4 arranged in the installation cavity 3 is plugged with a static contact 6 electrically matched with the overload protection unit, and one end of the movable terminal 5 arranged in the installation cavity 3 is provided with a mounting column 7 for fixing the overload protection unit.

[0030] The overload protection unit includes a bimetallic strip 8 for controlling the current overload disconnection, and a moving contact 9 electrically cooperating with the static contact 6 is inserted on the bimetallic strip 8; specifically, one end of the bimetallic strip 8 is in contact with the inner wall of the installation cavity 3, and the other end of the bimetallic strip 8 is inserted and fixedly connected with the installation column 7, and the bimetallic strip 8 is elastic.

[0031] The switch unit includes a button 10 movably disposed on the housing 1 ; specifically, the top end of the button 10 extends to the outside of the housing 1 , the bottom end of the button 10 is arranged in the installation cavity 3 , and the bottom end of the button 10 is in contact with the moving contact 9 .

[0032] A spring 11 for resetting the button 10 is sleeved on the button 10 near the bottom end; specifically, one end of the spring 11 is in contact connection with the inner wall of the installation cavity 3, and the other end of the spring 11 is in contact connection with the button 10.

[0033] The button 10 is integrally formed and made of plastic, playing an insulating role.

[0034] The working principle of the present utility model is as follows: during the use of the electrical equipment, the middle part of the bimetallic strip 8 bends downward, and the moving contact 9 on the bimetallic strip 8 is in contact connection with the static contact 6 on the static terminal 4 to ensure the normal passage of current; when the current carried by the load between the static contact 6 and the moving contact 9 is too large, the temperature of the moving contact 9 and the bimetallic strip 8 will rise, causing the bimetallic strip 8 to deform. During the deformation process, the elasticity of the bimetallic strip 8 gradually weakens until the moving contact 9 and the static contact 6 are completely separated, realizing the disconnection of the current and playing a protective role for the electrical appliance;

[0035] When the temperature of the bimetallic strip 8 drops, press the button 10 downward. During the downward movement of the button 10, the bottom end of the button 10 contacts and presses the moving contact 9 to move downward. The moving contact 9 drives the middle part of the bimetallic strip 8 to bend downward, and the static contact 6 and the moving contact 9 are re - contacted. During the pressing process, by setting the button 10 as a heat - resistant metal block structure, the button 10 can withstand a relatively high temperature, avoiding damage to the button 10, greatly improving its use stability and reducing the use cost; after pressing the button 10, the button 10 returns to its original position under the action of the resilience of the spring 11.

[0036] The advantages of the present utility model are as follows: one end of the bimetallic strip 8 is in contact connection with the inner wall of the installation cavity 3, and the other end of the bimetallic strip 8 is inserted and fixedly connected with the installation post 7. The connection method is simple, avoiding the abnormal operation of the bimetallic strip 8 caused by insecure fixation during the installation and fixation process by workers, and ensuring the disconnection and connection of the moving contact and the static contact under normal operation. Embodiment 2

[0037] As Figure 4 shown, different from Embodiment 1, in this embodiment, the cover plate 2 is fixedly connected to the side of the housing 1 by riveting nails 12, and one ends of the static terminal 4 and the moving terminal 5 arranged outside the installation cavity 3 are both bent in an "L" shape. Other structures are the same as those in Embodiment 1. Embodiment 3

[0038] As Figure 5As shown, different from Embodiment 1, in this embodiment, a pin 13 is detachably inserted at the bottom of the button 10. The pin 13 is a heat-resistant metal block structure, and the button 10 is made of plastic material for insulation. One end of the spring 11 abuts against the inner wall of the installation cavity 3, and the other end of the spring 11 abuts against the surface of the pin 13. The pin 13 is arranged in the installation cavity 3, and the bottom surface of the pin 13 is in abutting cooperation with the moving contact 9. Other structures are the same as those in Embodiment 1.

[0039] In the description of this specification, references to the terms "one embodiment", "some embodiments", "example", "specific example"

[0040] or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0041] The standard parts used in the present invention can all be purchased from the market. The special-shaped parts can be customized according to the records in the specification and drawings. The specific connection methods of each part all adopt conventional means such as bolts, rivets, welding, and bonding in the prior art, and will not be elaborated here.

[0042] The above content is only the preferred embodiment of the present invention. For those of ordinary skill in the art, various changes and modifications can be made in the specific implementation manners and application scopes according to the idea of the present invention. The content of this specification should not be construed as a limitation of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A current overload protector, comprising a housing and a cover plate hooked and fixed to the side of the housing, wherein a mounting cavity is provided in the housing, and characterized in that: An overload protection unit and a terminal unit electrically cooperating with the overload protection unit are provided in the installation cavity. A switch unit for pushing the overload protection unit to bend and energize is also provided in the installation cavity. The switch unit is arranged at the upper part of the overload protection unit, and the terminal unit is arranged at the lower part of the overload protection unit. One end of the overload protection unit is in contact with the inner wall of the installation cavity, and the other end of the overload protection unit is fixedly connected to the terminal unit.

2. A current overload protector according to claim 1, characterized in that: The terminal unit comprises a static terminal and a dynamic terminal, both of which are bent, and are clamped and connected in the installation cavity, and the bottom ends of the static terminal and the dynamic terminal extend to the outside of the shell.

3. A current overload protector according to claim 2, characterized in that: One end of the static terminal arranged in the installation cavity is plugged with a static contact electrically matched with the overload protection unit, and one end of the moving terminal arranged in the installation cavity is provided with a mounting column for fixing the overload protection unit.

4. A current overload protector according to claim 3, characterized in that: The overload protection unit includes a bimetallic strip for controlling the current overload disconnection, a moving contact electrically cooperating with a static contact is inserted on the bimetallic strip, one end of the bimetallic strip is in contact with the inner wall of the installation cavity, and the other end of the bimetallic strip is plugged and fixedly connected to the installation column.

5. A current overload protector according to claim 4, characterized in that: The switch unit comprises a button, which is movably arranged on the shell, the top of the button extends to the outside of the shell, the bottom of the button is arranged in the installation cavity, and the bottom of the button is in contact with the moving contact.

6. A current overload protector according to claim 5, characterized in that: A spring for resetting the button is sleeved near the bottom end of the button, one end of the spring is in contact with the inner wall of the installation cavity, and the other end of the spring is in contact with the button.

7. A current overload protector according to claim 5, characterized in that: The button is of one-piece design.

8. A current overload protector according to claim 2, characterized in that: The cover plate is fixedly connected to the side of the shell by riveting nails, and the ends of the static terminal and the dynamic terminal arranged outside the installation cavity are both in an "L"-shaped bend.

9. A current overload protector according to claim 5, characterized in that: The button bottom is separately plugged with a pin, which is a heat-resistant metal block structure.

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