Overload temperature control protector

Abstract

This application discloses an overload temperature control protector, relating to the field of protector technology. It includes a housing, a pair of terminals located at one end of the housing, and two connecting pieces (a first and a second) inside the housing connected to the terminals. A fixing block is positioned between the two connecting pieces. A movable spring is located at the end of the second connecting piece, contacting the first connecting piece. A first contact is located at the end of the first connecting piece. A second contact, staggered with the first contact, is located on the movable spring facing the first connecting piece. A bimetallic strip corresponding to the first connecting piece is located on the fixing block. A cover plate is located on the outside of the housing, and a push rod is slidably mounted within the cover plate. A pad is located on the push rod, contacting the movable spring. When heated, the bimetallic strip deforms, lifting the first connecting piece and separating it from the movable spring to cut off the circuit. After the equipment fault is cleared, pushing the push rod causes the insulating pad to reset the movable spring, restoring the circuit and preventing secondary equipment faults caused by the protector's rapid heat dissipation leading to automatic and rapid closure of the movable contact.

Description

Technical Field

[0001] This application relates to the field of protector technology, and in particular to overload temperature control protectors. Background Technology

[0002] Thermal protectors, as key components in the field of electrical safety, are widely used in various electrical equipment such as motors, heaters, ballasts, and power tools. Their core function is to monitor changes in the current or temperature of the equipment and quickly cut off the circuit when abnormal conditions such as overcurrent or overheating occur, preventing damage to the equipment caused by continuous abnormal operation or even safety accidents such as fires and electric shocks. The reliability of thermal protectors is directly related to the safe operation of electrical equipment and is an important line of defense for ensuring the safety of electrical systems, playing an irreplaceable role in industrial production and daily life.

[0003] Currently, most mainstream thermal protectors achieve their protection function based on the principle of bimetallic strip thermal deformation. Their core structure typically includes a bimetallic strip, a moving contact, a stationary contact, and a housing. When the electrical equipment experiences overcurrent or overheating, the bimetallic strip bends and deforms due to the increased temperature, causing the moving contact to separate from the stationary contact and cut off the circuit. When the equipment temperature drops, the bimetallic strip returns to its original shape, the moving contact and the stationary contact close again, the circuit is restored, and the automatic reset function is achieved.

[0004] Regarding the aforementioned technologies, the inventors believe that when the overcurrent in the equipment disappears instantly and the external ambient temperature drops sharply, the thermal protector itself dissipates heat too quickly, causing the bimetallic strip to cool and reset prematurely. The moving contact closes automatically immediately before the fundamental fault in the equipment is completely eliminated, and the circuit resumes conduction too early, which can easily lead to secondary faults in the equipment. Utility Model Content

[0005] The purpose of this application is to provide an overload temperature control protector to improve the problem that the moving contact will automatically close immediately if the fundamental fault of the equipment is not completely eliminated, and the circuit will prematurely resume conduction, which may easily cause secondary faults in the equipment.

[0006] The overload temperature controller provided in this application adopts the following technical solution: An overload temperature controller includes a housing and a pair of terminals located at one end of the housing. The inner wall of the housing has a connecting piece 1 and a connecting piece 2 connected to the terminals. A fixing block corresponding to the inner wall of the housing is located between the connecting pieces 1 and 2. A movable spring is located at the end of the connecting piece 2, contacting the connecting piece 1. A contact point 1 is located at the end of the connecting piece 1. A contact point 2, staggered with the contact point 1, is located on the movable spring facing the connecting piece 1. A bimetallic strip is located on the fixing block, contacting the connecting piece 1. A cover plate is bent along the length of the outer side of the housing. A push rod is slidably mounted through the cover plate on the side of the movable spring away from the fixing block. A pad is located on the push rod, contacting the movable spring.

[0007] By adopting the above technical solution, when the equipment is overloaded or overheated, the bimetallic strip deforms due to heat and pushes the connecting piece one, causing contact one and contact two to separate, cutting off the circuit. The moving spring moves contact two away from the connecting piece one, so that after the bimetallic strip is reset, the connecting piece one resets under its own elasticity and is offset from the moving spring. After the equipment fault is cleared, the push rod is pushed to make the insulating pad push the moving spring to reset, so that contact one and contact two are alternately set to conduct the circuit. This increases the controllability of the reset, improves the safety redundancy of the protector, and prevents the protector from automatically and quickly closing the moving contact due to excessive heat dissipation, which could lead to secondary equipment faults.

[0008] Optionally, a guide arc surface is provided on the side of contact one away from connecting piece one and the side of contact two facing connecting piece one, and a limiting plane is provided on the sidewall after contact one and contact two make staggered contact.

[0009] By adopting the above technical solution, after the bimetallic strip is reset, when the push rod pushes the moving spring closer to the connecting piece one, the guiding effect of the guide arc surface can cause the contact point two of the moving spring to pass over the contact point one of the connecting piece one, so that the limiting planes of the two contacts come into contact and limit and fix the two contacts, ensuring reliable contact when the circuit is conducting. When the bimetallic strip is heated and deformed, it lifts the connecting piece two, and the contact point one and contact point two can be smoothly separated by the limiting plane.

[0010] Optionally, an elastic element is provided between the outer side of the cover plate and the push rod, and the push rod is provided with a push handle that contacts the elastic element.

[0011] By adopting the above technical solution, the elastic element between the outer side of the cover plate and the push rod can provide a reset force after the push rod is manually operated, so that the push rod automatically returns to its original position after being released. This avoids the push rod being in a state of stress for a long time, which would prevent the moving spring from returning to a position away from the connecting piece 1 through its own elasticity, thus preventing the protector from conducting when the bimetallic strip is reset.

[0012] Optionally, the bimetallic strip has a plurality of top blocks at its end that abut against the connecting piece, and the top of the top blocks is arc-shaped.

[0013] By adopting the above technical solution, the top block on the bimetallic strip that abuts against the connecting piece 1 adopts an arc design, which can reduce the contact wear between the bimetallic strip and the connecting piece 1 when the bimetallic strip deforms, avoid local stress concentration caused by sharp structures to the connecting piece 1, and extend the service life of the connecting piece 1; at the same time, the multiple top blocks at the end of the bimetallic strip can make the thrust of the bimetallic strip more evenly transmitted to the connecting piece 1, ensuring that the connecting piece 1 deforms stably after being subjected to force, and ensuring reliable separation of contact 1 and contact 2.

[0014] Optionally, a clearance space is left between the cover plate and the connecting piece 1 to allow the bimetallic strip to deform and push the connecting piece 1 to disconnect from the moving spring.

[0015] By adopting the above technical solution, the clearance space between the cover plate and the connecting piece 1 provides sufficient movement margin for the bimetallic strip to deform under heat, avoiding the deformation obstruction caused by insufficient space when the bimetallic strip pushes the connecting piece 1, ensuring that the connecting piece 1 can be smoothly pushed to the position where the contact 1 and contact 2 are completely separated, and ensuring that the circuit is reliably cut off in case of overload.

[0016] Optionally, the housing is provided with a heating element that is connected in series with the wiring terminal and located close to the bimetallic strip.

[0017] By adopting the above technical solution, the heating element installed inside the housing is connected in series with the wiring terminal and close to the bimetallic strip. When an overcurrent occurs in the circuit, the heating element can quickly generate heat and transfer it to the bimetallic strip, accelerating the deformation process of the bimetallic strip and shortening the response time from the occurrence of overcurrent to the separation of contacts. This allows the protector to cut off the circuit more quickly and reduce the continuous damage of overcurrent to electrical equipment.

[0018] Optionally, the end of the terminal block furthest from the base is provided with a retaining plate for fixing the wire.

[0019] By adopting the above technical solution, the locking piece at the end of the terminal away from the base can clamp the wire through deformation, thereby enhancing the mechanical connection strength between the wire and the terminal and preventing the wire from loosening or falling off due to external forces such as vibration and pulling.

[0020] Optionally, the wiring terminals are provided with connection holes for connecting wires between the packaging plates.

[0021] By adopting the above technical solution, the connection holes between the terminals and the connecting plates are connected to the wires, which further enhances the connection between the wires and the terminals, improves the installation adaptability of the protector, and ensures that a stable electrical connection can be maintained in a variety of application scenarios.

[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. When the equipment is overloaded or overheated, the bimetallic strip deforms due to heat and pushes the connecting piece one, causing contact one and contact two to separate, cutting off the circuit. The moving spring moves contact two away from the connecting piece one, and after the bimetallic strip is reset, the connecting piece one and the moving spring are staggered. After the equipment fault is cleared, the push rod is pushed to make the insulating pad push the moving spring to reset, so that contact one and contact two are staggered to conduct the circuit, which increases the controllability of the reset, improves the safety redundancy of the protector, and prevents the moving contact from automatically closing quickly due to the protector's own heat dissipation, which would cause secondary equipment faults. 2. After the bimetallic strip is reset, when the push rod pushes the movable spring closer to the connecting piece one, the guide arc surface can guide the contact point two of the movable spring to pass over the contact point one of the connecting piece one, so that the limiting planes of the two contacts come into contact and limit and fix the two contacts, ensuring reliable contact when the circuit is conducting. When the bimetallic strip is heated and deformed, it will lift the connecting piece two, and the contact point one and the contact point two can be smoothly separated by the limiting plane. 3. The heating element inside the housing is connected in series with the wiring terminal and close to the bimetallic strip. When an overcurrent occurs in the circuit, the heating element can quickly generate heat and transfer it to the bimetallic strip, accelerating the deformation process of the bimetallic strip and shortening the response time from the occurrence of overcurrent to contact separation. This allows the protector to cut off the circuit more quickly and reduce the continuous damage of overcurrent to electrical equipment. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overload temperature controller. Figure 2 This is a cross-sectional schematic diagram of an overload temperature controller. Figure 3 yes Figure 2 A magnified view of part A in the middle.

[0024] In the diagram, 1. Housing; 11. Cover plate; 12. Push rod; 121. Pad block; 13. Elastic element; 14. Push handle; 15. Clearance space; 2. Wiring terminal; 21. Encasing plate; 22. Connecting hole; 3. Connecting piece one; 31. Contact one; 32. Guide arc surface; 33. Limiting plane; 4. Connecting piece two; 41. Moving spring; 42. Contact two; 5. Fixing block; 6. Bimetallic strip; 61. Top block; 7. Heating element. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1 -Appendix Figure 3 This application will be described in further detail below.

[0026] Overload temperature controller, refer to Figure 1 and Figure 2The device includes a housing 1 and a pair of terminals 2 that are inserted into the side wall of the housing 1 at one end. Connecting pieces 1 3 and 2 4, which are connected to the terminals 2, are respectively provided on the inner side wall of the housing 1. Connecting pieces 1 3 and 2 4 are riveted and soldered to the terminals 2. Connecting piece 1 3 is made of a conductive reset metal spring, and connecting piece 2 4 is made of a conductive metal fixing piece. A fixing block 5, which corresponds to the inner side wall of the housing 1, is provided between connecting pieces 1 3 and 2 4. The housing 1 and the fixing block 5 are made of insulating plastic material. A movable spring 41, which contacts connecting piece 1 3, is riveted to the end of connecting piece 2 4. A long strip of conductive contact 1 31 is riveted to the end of connecting piece 1 3. A conductive contact 2 42, which is staggered with contact 1 31, is riveted to the movable spring 41 facing connecting piece 1 3.

[0027] Reference Figure 1 and Figure 2 A bimetallic strip 6, which contacts the connecting piece 3, is fixed to the side wall of the fixed block 5 with screws. The bimetallic strip 6 is made of two metal materials with different coefficients of expansion. An insulating plastic cover plate 11 is bent along the length of the outer side of the housing 1 and is fastened to the housing 1. A push rod 12 is slidably arranged through the cover plate 11 on the side of the movable spring 41 away from the fixed block 5. A pad 121, which contacts the movable spring 41, is glued to the end of the push rod 12. When the equipment... In case of overload or overheating, the bimetallic strip 6 deforms due to heat and pushes the connecting piece 3, causing contact 31 to separate from contact 42, thus cutting off the circuit. The moving spring 41 drives contact 42 away from the connecting piece 3, so that after the bimetallic strip 6 is reset, the connecting piece 3 resets under its own elasticity and is offset from the moving spring 41. After the equipment fault is cleared, the push rod 12 pushes the insulating pad 121 to push the moving spring 41 to reset, so that contacts 31 and 42 are alternately set to conduct the circuit.

[0028] Reference Figure 2 and Figure 3 A guide arc surface 32 is provided on the side of contact 1 31 away from connecting piece 1 3 and on the side of contact 2 42 facing connecting piece 1 3. A limiting plane 33 is provided on the side wall after contact 1 31 and contact 2 42 are in staggered contact. When push rod 12 pushes moving spring 41 close to connecting piece 1 3, the guiding arc surface 32 can guide the contact 2 42 of moving spring 41 to pass over contact 1 31 of connecting piece 1 3, so that the limiting planes 33 of the two contacts come into contact and limit and fix the two contacts. A spring as an elastic element 13 is provided between the outer side of cover plate 11 and push rod 12, so that push rod 12 automatically returns to its original position after being released. A push handle 14 that contacts the elastic element 13 is threadedly connected to the end of push rod 12 away from housing 1.

[0029] Reference Figure 2 and Figure 3A plurality of top blocks 61 are riveted to the end of the bimetallic strip 6 and abut against the connecting piece 3. The top of the top block 61 is rounded. When the bimetallic strip 6 deforms, the top block 61 pushes the connecting piece 3 away from the moving spring 41. A clearance space 15 is left between the cover plate 11 and the connecting piece 3 to allow the bimetallic strip 6 to deform and push the connecting piece 3 to disconnect from the moving spring 41. A heating element 7 is installed in the housing 1 and connected in series with the terminal 2 and located close to the bimetallic strip 6. The heating element 7 includes a metal heat-conducting shell fixed to one side of the fixing block 5 with screws and a heating resistor (not shown in the figure) installed in the housing and connected in series with the terminal 2 by wires. When an overcurrent occurs in the circuit, the heating element 7 can quickly generate heat and transfer it to the bimetallic strip 6, accelerating the deformation process of the bimetallic strip 6 and shortening the response time from the occurrence of overcurrent to contact separation.

[0030] Reference Figure 1 and Figure 2 An integrally formed retaining plate 21 for fixing wires is provided at the end of the terminal 2 away from the base. A connection hole 22 is opened between the terminal 2 and the retaining plate 21. The connection hole 22 between the retaining plates of the terminal 2 is connected to the wire. The retaining plates can clamp the wire through deformation, which enhances the mechanical connection strength between the wire and the terminal 2 and prevents the wire from loosening or falling off due to external forces such as vibration and pulling. The implementation principle of this application embodiment is as follows: When the circuit is conducting, the current forms a loop through terminal 2, connecting piece 3, contact 31, contact 42, moving spring 41, and connecting piece 4. At this time, the bimetallic strip 6 is in its natural state, the top block 61 is in light contact with connecting piece 3, and the moving spring 41 relies on its own elasticity to make the contacts make tight contact, ensuring stable circuit conduction. When an overcurrent occurs in the circuit, the series-connected heating element 7 heats up rapidly due to the increased current. This heat is transferred to the bimetallic strip 6. If the device itself is overheated, the heat will also be directly conducted to the bimetallic strip 6. The bimetallic strip 6, after being heated, bends and deforms, pushing the connecting piece 3 through the top block 61, causing contact 31 to separate from contact 42 and cutting off the circuit. After the circuit is cut off, even if the bimetallic strip 6 returns to its original position due to cooling, the moving spring 41 cannot automatically move contact 42 to contact contact 31 and close the circuit. The operator must push the handle 14 to press the push rod 12. The push rod 12, through the pad 121, moves the moving spring 41 closer to the connecting piece 3, causing contact 31 to re-contact contact 42. Releasing the handle 14 causes the elastic element 13 to move the push rod 12 back to its original position, while the moving spring 41 maintains the contact closure due to its own elasticity, restoring circuit continuity. This prevents secondary equipment malfunctions caused by the protector automatically and rapidly closing its moving contacts due to excessive heat dissipation.

[0031] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. An overload temperature controller, characterized in that: Includes a housing (1) and a pair of terminals (2) located at one end of the housing (1). The inner wall of the housing (1) is provided with connecting piece 1 (3) and connecting piece 2 (4) respectively connected to the terminals (2). A fixing block (5) corresponding to the inner wall of the housing (1) is provided between the connecting piece 1 (3) and connecting piece 2 (4). A movable spring (41) is provided at the end of the connecting piece 2 (4) and contacts the connecting piece 1 (3). A contact point (31) is provided at the end of the connecting piece 1 (3). The movable spring (41) is provided with a contact point (42) that is staggered with the contact point (31) facing the connecting piece (3). The fixing block (5) is provided with a bimetallic strip (6) that contacts the connecting piece (3). The outer side of the housing (1) is bent along its length and is provided with a cover plate (11). The movable spring (41) is slidably provided with a push rod (12) through the cover plate (11) on the side away from the fixing block (5). The push rod (12) is provided with a pad (121) that contacts the movable spring (41).

2. The overload temperature controller according to claim 1, characterized in that: The side of the first contact (31) away from the first connecting piece (3) and the side of the second contact (42) facing the first connecting piece (3) are provided with guide arc surfaces (32), and the sidewalls of the first contact (31) and the second contact (42) after they are in staggered contact are provided with limiting planes (33).

3. The overload temperature controller according to claim 2, characterized in that: An elastic element (13) is provided between the outer side of the cover plate (11) and the push rod (12), and the push rod (12) is provided with a push handle (14) that contacts the elastic element (13).

4. The overload temperature controller according to claim 3, characterized in that: The bimetallic sheet (6) has a plurality of top blocks (61) at its end that abut against the connecting piece (3), and the top of the top block (61) is arc-shaped.

5. The overload temperature controller according to claim 4, characterized in that: There is a clearance space (15) between the cover plate (11) and the connecting piece (3) to allow the bimetallic strip (6) to deform and push the connecting piece (3) to disconnect from the moving spring (41).

6. The overload temperature controller according to claim 5, characterized in that: The housing (1) is provided with a heating element (7) that is connected in series with the wiring terminal (2) and is located close to the bimetallic strip (6).

7. The overload temperature controller according to claim 6, characterized in that: The terminal block (2) is provided with a retaining plate (21) for fixing the wire at the end away from the base.

8. The overload temperature controller according to claim 7, characterized in that: The terminal block (2) is located between the enclosure plates (21) and has a connection hole (22) for connecting to the wire.

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