A measurement switch with a bimetallic strip

Abstract

The utility model discloses a kind of measurement switches with bimetal, including plastic shell, operating module, carrier wave module and measurement module are provided on the plastic shell, the operating module includes operating handle and several disconnecting pieces, the operating handle is connected with disconnecting piece transmission, operating handle and the limiting buckle for keeping operating handle in closing position are set between the plastic shell, the limiting buckle swing connection is in plastic shell, one end of the limiting buckle is provided with limiting dog, the other end is provided with the abutment table for driving limiting buckle swing so that limiting dog is separated from operating handle, the disconnecting piece extends wiring row outside plastic shell, the plastic shell is provided with bimetal in wiring row side, the end of the bimetal is provided with abutment arm, the end of the abutment arm is close to abutment table setting. Its structure is simple and compact, layout is reasonable, effectively add heat protection, with good use effect.

Description

Technical Field

[0001] This utility model belongs to the field of switch and electrical technology, and particularly relates to a measuring switch with a bimetallic strip. Background Technology

[0002] Measuring switches are widely used in low-voltage power distribution and energy metering circuits, serving both circuit on / off control and energy parameter metering functions, and are one of the core components of terminal power distribution systems. Existing conventional measuring switches typically only have an electromagnetic tripping mechanism, providing only instantaneous disconnection protection against short-circuit faults. They lack effective protection against continuous overheating faults caused by overload operation, poor terminal contact, or accumulated ambient temperature rise. Some switch products with added thermal protection often have their thermal tripping modules independently located outside the operating mechanism. This not only results in redundant overall structure and cumbersome assembly processes, but also easily leads to delayed thermal deformation response due to excessively long transmission paths, failing to trigger tripping in time at the initial stage of overheating. This poses safety hazards such as excessive temperature rise, accelerated component aging, and even electrical fires. Furthermore, external thermal protection structures increase the overall size of the switch, making it difficult to adapt to the current miniaturization and integration requirements of power distribution equipment. Utility Model Content

[0003] To address the shortcomings of existing technologies, this utility model provides a measuring switch with a bimetallic strip, which has a simple and compact structure, a reasonable layout, and effectively adds thermal protection, resulting in good performance.

[0004] To achieve the above objectives, this utility model provides a measuring switch with a bimetallic strip, including a plastic housing. The plastic housing is equipped with an operation module, a carrier module, and a measuring module. The operation module includes an operation handle and several disconnecting components. The operation handle is kinetically connected to the disconnecting components. A limit latch is provided between the operation handle and the plastic housing to hold the operation handle in the closed position. The limit latch is oscillatingly connected to the plastic housing. One end of the limit latch is provided with a limit claw, and the other end is provided with a contact platform for driving the limit latch to oscillate and disengage the limit claw from the operation handle. A terminal block extends outward from the plastic housing from the disconnecting component. A bimetallic strip is provided beside the terminal block on the plastic housing. An abutment arm is provided at the end of the bimetallic strip, and the end of the abutment arm is positioned close to the contact platform.

[0005] The advantages of this design are as follows: By integrating the contact platform into the existing trip limit latch and placing a bimetallic strip with a contact arm next to the terminal block, the thermal protection function is directly integrated into the trip structure. This eliminates the need for additional independent trip levers and transmission components, resulting in a compact overall structure that does not increase the switch size. It aligns with the trend towards miniaturization and integration of measurement switches, while also reducing assembly steps and structural redundancy. The bimetallic strip is positioned close to the heat source terminal block, and the contact arm acts directly on the contact platform of the limit latch, resulting in a very short transmission path. In case of overheating deformation, it can instantly push the limit latch to swing, causing the limit pawl to disengage from the operating handle and complete the tripping. This provides a fast thermal protection response and effectively prevents temperature accumulation. In case of overheating, the deformation of the bimetallic strip directly triggers the limit latch to unlock, reliably achieving the transition from the closed to the open state. This provides effective protection against continuous overheating faults caused by circuit overload, poor terminal contact, etc., improving the electrical safety of the power distribution circuit.

[0006] As a further feature of this invention, the outer peripheral wall of the abutment arm is provided with a mating thread, and the end of the bimetallic strip is provided with a threaded hole, wherein the abutment arm is threadedly engaged with the threaded hole.

[0007] The advantages of this design are as follows: The threaded contact arm structure allows for precise control of the initial gap between the contact arm end and the contact platform by adjusting the extension length of the contact arm through screwing. This calibrates the thermal tripping operating temperature threshold and adapts to product requirements with different rated current specifications. Simultaneously, the threaded connection facilitates assembly, provides reliable connection strength, and is not easily loosened by long-term temperature changes and vibrations, ensuring consistent thermal tripping accuracy. Furthermore, this structure eliminates the need to replace bimetallic strips of different specifications; tripping parameters can be adjusted simply by regulating the extension of the contact arm, improving component versatility and reducing production, inventory, and material management costs.

[0008] As a further feature of this invention, the other end of the bimetallic strip is connected to the terminal block via a heat-conducting metal strip.

[0009] The advantages of this design are: it allows the working heat of the terminal block to be quickly and evenly conducted to the bimetallic strip, enabling the bimetallic strip to accurately sense the actual heating state of the circuit, avoiding delays in thermal protection action due to lag in heat conduction, and improving the accuracy and timeliness of thermal tripping; at the same time, the heat-conducting metal strip also serves as a fixed support, stably positioning the bimetallic strip beside the terminal block, improving the installation firmness of the bimetallic strip, and reducing the interference of switch opening and closing vibrations on the deformation accuracy of the bimetallic strip; in addition, this indirect heat conduction structure eliminates the need to directly connect the bimetallic strip into the main circuit, simplifying the main circuit wiring design, reducing assembly difficulty, and preventing the bimetallic strip from being directly subjected to high current impact, effectively extending its service life.

[0010] As a further feature of this invention, the thermally conductive metal sheet includes a connecting portion and a bonding portion. The connecting portion is connected to a terminal block, and the bonding portion is connected to the side wall of the bimetallic sheet. The connecting portion is arranged perpendicular to the bonding portion.

[0011] The advantages of this design are as follows: the bonding part can form a large surface area contact with the side wall of the bimetallic strip, effectively increasing the thermal contact area, reducing contact thermal resistance, improving heat conduction efficiency, and ensuring uniform heating and accurate deformation direction and amount of the bimetallic strip; the bending design of the connecting part perpendicular to the bonding part can adapt to the spatial orientation between the terminal block and the bimetallic strip, allowing the thermally conductive metal strip to be tightly bonded to both components simultaneously without the need for additional secondary bending adaptation, resulting in more accurate assembly positioning; at the same time, the vertical bending structure improves the structural strength of the thermally conductive metal strip itself, which can buffer the vibration and impact during switch operation, prevent loosening of the connection position, and ensure long-term thermal stability and structural reliability. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the layout structure of an embodiment of the present utility model; Figure 2 This is a schematic diagram of the limiting buckle in an embodiment of the present utility model; Figure 3 This is a schematic diagram of the cooperation structure between the limiting buckle and the bimetallic strip in an embodiment of this utility model. Detailed Implementation

[0013] An example of this utility model is a measuring switch with a bimetallic strip. Figures 1 to 3As shown: The device includes a plastic housing, on which an operation module, a carrier module 2, and a measurement module 3 are mounted. The operation module includes an operation handle 4 and several disconnecting components 8. The operation handle 4 is connected to the disconnecting components 8 via a transmission connection. A limit latch 5 is provided between the operation handle 4 and the plastic housing to hold the operation handle 4 in the closed position. The limit latch 5 is oscillatingly connected to the plastic housing. One end of the limit latch 5 is provided with a limit claw 51, and the other end is provided with a contact platform 52 for driving the limit latch 5 to oscillate and disengage the limit claw 51 from the operation handle 4. The disconnecting component 8 extends outward from the plastic housing with a terminal block 11. A bimetallic strip 6 is provided beside the terminal block 11 on the plastic housing. An abutment arm 61 is provided at the end of the bimetallic strip 6, and the end of the abutment arm 61 is located near the contact platform 52. The advantages of this design are as follows: By integrating the contact plate 52 into the existing trip limit latch 5 and setting a bimetallic strip 6 with a contact arm 61 next to the terminal block 11, the thermal protection function is directly integrated into the trip structure. No additional independent trip levers and transmission components are needed, resulting in a compact overall structure that does not increase the switch size. This aligns with the trend towards miniaturization and integration of measurement switches, while also reducing assembly steps and structural redundancy. The bimetallic strip 6 is positioned close to the heat source terminal block 11, and the contact arm 61 directly acts on the contact plate 52 of the limit latch 5. The transmission path is extremely short, allowing for instantaneous pushing of the limit latch 5 to swing during overheating deformation, causing the limit pawl 51 to disengage from the operating handle 4 and complete the tripping. This results in a fast thermal protection response, effectively preventing temperature accumulation. In case of overheating, the deformation of the bimetallic strip 6 directly triggers the unlocking of the limit latch 5, reliably achieving the transition from the closed to the open state. This provides effective protection against continuous overheating faults caused by circuit overload, poor terminal contact, etc., improving the electrical safety of the power distribution circuit.

[0014] As a further feature of this embodiment, the outer peripheral wall of the abutment arm 61 is provided with mating threads, and the end of the bimetallic strip 6 is provided with a threaded hole, with the abutment arm 61 threadedly engaging with the threaded hole. The advantages of this design are: the threaded abutment arm 61 structure allows for precise control of the initial gap between the end of the abutment arm 61 and the abutment platform 52 by adjusting the extension length of the abutment arm 61 through screwing, thereby calibrating the thermal tripping operating temperature threshold and adapting to product requirements with different rated current specifications; simultaneously, the threaded connection is convenient to assemble, has reliable connection strength, and is not easily loosened by long-term temperature changes and vibrations, ensuring consistent thermal tripping accuracy; furthermore, this structure eliminates the need to replace bimetallic strips 6 of different specifications, allowing adjustment of tripping parameters simply by adjusting the extension amount of the abutment arm 61, improving component versatility and reducing production preparation and material management costs.

[0015] As a further feature of this embodiment, the other end of the bimetallic strip 6 is connected to the terminal block 11 via a heat-conducting metal sheet 7. The advantages of this configuration are: it allows the working heat of the terminal block 11 to be quickly and evenly conducted to the bimetallic strip 6, enabling the bimetallic strip 6 to accurately sense the actual heating state of the circuit, avoiding delays in thermal protection action due to lag in heat conduction, and improving the accuracy and timeliness of thermal tripping; simultaneously, the heat-conducting metal sheet 7 also serves as a fixed support, stably positioning the bimetallic strip 6 beside the terminal block 11, improving the installation firmness of the bimetallic strip 6, and reducing the interference of switch opening and closing vibrations on the deformation accuracy of the bimetallic strip 6; furthermore, this indirect heat conduction structure eliminates the need to directly connect the bimetallic strip 6 into the main circuit, simplifying the main circuit wiring design, reducing assembly difficulty, and preventing the bimetallic strip 6 from being directly subjected to high current impacts, effectively extending its service life.

[0016] As a further feature of this embodiment, the thermally conductive metal sheet 7 includes a connecting portion and a bonding portion. The connecting portion is connected to the terminal block 11, and the bonding portion is connected to the side wall of the bimetallic sheet 6. The connecting portion is perpendicular to the bonding portion. The advantages of this configuration are: the bonding portion can form a large-area surface contact with the side wall of the bimetallic sheet 6, effectively increasing the thermal contact area, reducing the contact thermal resistance, improving the heat conduction efficiency, and ensuring that the bimetallic sheet 6 is heated evenly and that the deformation direction and deformation are accurate; the bending design of the connecting portion perpendicular to the bonding portion can adapt to the spatial orientation between the terminal block 11 and the bimetallic sheet 6, allowing the thermally conductive metal sheet 7 to be tightly bonded to both components simultaneously without the need for additional secondary bending adaptation, resulting in more accurate assembly positioning; at the same time, the vertical bending structure improves the structural strength of the thermally conductive metal sheet 7 itself, which can buffer the vibration and impact during switch operation, prevent the connection position from loosening, and ensure the thermal stability and structural reliability of long-term use.

[0017] The above examples are merely one preferred embodiment of this utility model. Ordinary variations and substitutions made by those skilled in the art within the scope of this utility model's technical solution are all included within the protection scope of this utility model.

Claims

1. A measuring switch with a bimetallic strip, comprising a plastic housing, wherein an operation module, a carrier module, and a measuring module are disposed on the plastic housing, the operation module comprising an operation handle and a plurality of disconnecting components, the operation handle being pulsatorically connected to the disconnecting components, and a limit latch for holding the operation handle in the closed position is disposed between the operation handle and the plastic housing, the limit latch being oscillatingly connected to the plastic housing, characterized in that: One end of the limiting buckle is provided with a limiting claw, and the other end is provided with a contact platform for driving the limiting buckle to swing so that the limiting claw disengages from the operating handle. The split component extends outward from the plastic shell with a terminal block. The plastic shell is provided with a bimetallic strip next to the terminal block. The end of the bimetallic strip is provided with a contact arm, and the end of the contact arm is located close to the contact platform.

2. The measuring switch with a bimetallic strip according to claim 1, characterized in that: The outer peripheral wall of the abutment arm is provided with a mating thread, and the end of the bimetallic strip is provided with a threaded hole, and the abutment arm is threadedly engaged with the threaded hole.

3. The measuring switch with a bimetallic strip according to claim 1, characterized in that: The other end of the bimetallic strip is connected to the terminal block via a heat-conducting metal strip.

4. The measuring switch with a bimetallic strip according to claim 3, characterized in that: The thermally conductive metal sheet includes a connecting part and a bonding part. The connecting part is connected to the terminal block, and the bonding part is connected to the side wall of the bimetallic sheet. The connecting part is arranged perpendicular to the bonding part.

Images