A molded case circuit breaker with adjustable overload alarm and non-tripping function

Abstract

The present invention discloses a molded case circuit breaker with an adjustable overload alarm non-tripping function, comprising a shell, a traction rod arranged on the shell, an overload protection mechanism and a limit structure, and an alarm trigger switch arranged on the limit structure and opposite to the traction rod. The limit structure has a function of being driven to drive the alarm trigger switch to move to a blocking position for blocking the traction rod from tripping, and being driven to drive the alarm trigger switch to move to a separation position for releasing the blocking of the traction rod, so that the alarm trigger switch is triggered when the traction rod rotates in a tripping direction. The molded case circuit breaker adopting the technical solution has an overload alarm non-tripping function and an overload tripping function, and can be freely switched between the two without changing the product. The application range is wide, the adjustment operation is convenient, and the product inspection is relatively simple. The one-time qualified rate is greatly improved, and customers have a variety of choices when using it.

Description

Technical Field

[0001] The invention relates to the technical field of low-voltage electrical appliances, and in particular to a molded case circuit breaker with an adjustable overload alarm non-tripping function. Background Art

[0002] Molded case circuit breakers have long-delay overload and short-circuit instantaneous protection functions. In low-voltage power distribution systems, they are often used as terminal switches or branch switches, replacing the fuses and knife switches commonly used in the past. At present, molded case circuit breakers with overload release occupy the mainstream of this type of products on the market, but with the development of technology, some important places that require continuous power supply, such as fire protection, hospitals, data management centers, etc., need to provide special protection of alarm without power outage, that is, in the event of overload, power supply must still be maintained, and only an overload alarm needs to be issued to remind the staff to adjust the load and make corresponding treatment.

[0003] For this reason, products with overload alarm and non-tripping functions have also appeared on the market. For example, Chinese patent document CN206992026U discloses a molded case circuit breaker with a thermal overload alarm and non-tripping function, including a base, a circuit board, a bimetallic strip, a pull rod, a bracket and a cam screw. The circuit board is fixed on the base, and a micro switch connected to an external alarm device through a lead is provided on the circuit board. One end of the bimetallic strip is connected to a heat generating element, and the other end thereof is fixedly connected to the pull rod, the bracket and the cam screw in sequence. When the bimetallic strip is overloaded and bent, the cam screw is driven to trigger the micro switch, and an alarm signal is output to the external alarm device. Although the molded case circuit breaker of the above document can realize the function of overload alarm without tripping, the following technical problems still exist in practical applications: 1. The above structure is not only complicated to install, but also the double metal no longer contacts the traction rod of the circuit breaker after the pull rod and the screw are set, which makes the calibration more difficult and the one-time pass rate is low; 2. More importantly, the molded case circuit breaker products are all customized and shipped out of the factory. Customers cannot choose products with overload alarm without tripping or overload tripping functions by themselves, unless the product is replaced, which makes the scope of application small, the operation cumbersome, and cannot meet user needs well. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problems that the molded case circuit breaker in the prior art cannot select the overload alarm non-tripping or overload tripping function by itself, has a small scope of application, is cumbersome to operate, and is difficult to verify the product, and cannot meet the needs of users well. Thus, a molded case circuit breaker is provided which is easy to verify, can freely switch between the overload alarm non-tripping function and the overload tripping function, has a wide scope of application, is easy to operate, and meets the various needs of users.

[0005] In order to solve the above technical problems, the present invention provides a molded case circuit breaker with an adjustable overload alarm non-tripping function, comprising a housing, a traction rod arranged on the housing and an overload protection mechanism, wherein when the overload protection mechanism is triggered, the traction rod is driven to trip and rotate, so as to realize the opening of the molded case circuit breaker, and further comprising:

[0006] a limiting structure, the limiting structure having a blocking position driven to move toward the traction rod to block the traction tripping, and a separation position driven to move away from the traction rod to release the blocking of the traction rod;

[0007] An alarm trigger switch is arranged on the limiting structure and is arranged opposite to the traction rod. When the traction rod rotates toward the tripping direction, the alarm trigger switch is triggered.

[0008] As a preferred solution, a driving mechanism for driving the limiting structure to move toward or away from the traction rod is provided on the housing.

[0009] As a preferred solution, a mounting groove located on one side of the traction rod is provided in the shell, and the limiting structure is a push rod component movably provided in the mounting groove, and the movement path of the push rod component partially overlaps with the movement path of the traction rod.

[0010] As a preferred embodiment, a mating groove is provided on the push rod component, and the driving mechanism has a driving cam rotatably disposed in the mating groove and driven by the driving mechanism, and the protrusion of the driving cam pushes against the groove walls at both ends of the mating groove within its rotation stroke, thereby driving the push rod component to move in the mounting groove toward or away from the traction rod.

[0011] As a preferred solution, the driving mechanism includes: a lock body arranged on the shell and a key cooperating with the lock body, and a lock core of the lock body linked to the driving cam, and the lock core of the lock body is driven to rotate when the key is rotated.

[0012] As a preferred solution, the push rod component and the driving cam are arranged below the lock body, a mounting hole is formed on the driving cam, and one end of the lock core extending downward from the lock body is fitted and mounted in the mounting hole.

[0013] As a preferred solution, the alarm trigger switch is arranged on one end of the push rod component facing the traction rod, has a trigger button that cooperates with the traction rod, and the alarm trigger switch is a micro switch.

[0014] As a preferred embodiment, a circuit board connected to the alarm trigger switch is provided on one end of the push rod component, and the shell includes a middle cover on which the driving mechanism is installed, and a dovetail groove is provided on the side wall of the middle cover, and the control circuit on the circuit board is led out of the shell through the dovetail groove.

[0015] As a preferred solution, the overload protection mechanism includes a bimetallic strip and a heat-conducting element for heating the bimetallic strip, and the bimetallic strip is arranged on the other side of the traction rod relative to the push rod component.

[0016] As a preferred solution, one end of the bimetallic strip is a fixed end fixedly matched with the heat-conducting element, and the other end is a free end bent by heat, and the free end is provided with an adjustment screw facing the traction rod.

[0017] The technical solution of the present invention has the following advantages compared with the prior art:

[0018] 1. In the molded case circuit breaker provided by the present invention, when the user selects the overload alarm function, the limit structure is driven to drive the alarm trigger switch to move to a blocking position that blocks the traction rod from tripping, thereby limiting the normal tripping of the traction rod. At this time, if an overload occurs in the line, the traction rod is driven by the overload protection mechanism to trip and rotate, and the alarm trigger switch is triggered before the tripping state is reached, so that the alarm trigger switch is turned on and an overload alarm signal is sent out, so that the staff can quickly troubleshoot the fault and the circuit breaker is still in working condition; when the user selects the overload tripping function, the limit structure is driven to drive the alarm trigger switch to move to a separation position that releases the blocking of the traction rod, so that the traction rod is no longer blocked and restricted by the alarm trigger switch. At this time, if a fault current occurs in the line, the traction rod is triggered to trip normally to achieve the tripping and opening of the circuit breaker. The molded case circuit breaker adopting this technical solution has a simple structure and can directly adjust the trigger distance between the overload protection mechanism and the traction rod. The product inspection is relatively simple, and the first-time pass rate is greatly improved. It can freely switch between the overload alarm non-tripping function and the overload tripping function without replacing the product. It has a wide range of applications and is easy to operate, meeting the various usage needs of users.

[0019] 2. In the molded case circuit breaker provided by the present invention, the limiting structure is a push rod component movably arranged in the installation groove, and the movement path of the push rod component partially overlaps with the movement path of the traction rod. The advantage of such a design is that the alarm trigger switch is driven by the push rod component to be on the movement path of the traction rod, and can touch the alarm trigger switch when the traction rod is disengaged and rotated. At the same time, the alarm trigger switch blocks the traction rod from disengaging movement, thereby realizing the function of the circuit breaker product overload alarm not being tripped, and after the traction rod returns to its position, the alarm trigger switch is released and the alarm signal is cancelled. The whole process does not affect the normal operation of the line.

[0020] 3. In the molded case circuit breaker provided by the present invention, the driving mechanism drives the driving cam to rotate in the matching groove of the push rod component. The cam portion of the driving cam pushes the groove walls at both ends of the matching groove respectively during the rotation process, so that the push rod component moves closer to or away from the traction rod under the pushing action of the driving cam, that is, the alarm trigger switch is moved closer to or away from the traction rod position. Through the above-mentioned setting, the rotational motion of the driving cam is converted into the translational motion of the push rod component. The design is reasonable and the matching transmission is reliable.

[0021] 4. In the molded case circuit breaker provided by the present invention, the driving mechanism includes a lock body arranged on the shell and a key cooperating with the lock body, and the lock body has a lock core linked to the driving cam. When the key is rotated, the lock core of the lock body is driven to rotate. This structural arrangement drives the lock core to rotate in a linked manner by driving the cam by rotating the key forward or reversely by a certain angle, thereby realizing that the push rod component drives the alarm trigger switch to move closer to or away from the traction rod, that is, the circuit breaker product can select the overload alarm non-tripping function or the overload tripping function by itself, which is easy to operate.

[0022] 5. In the molded case circuit breaker provided by the present invention, a dovetail groove is provided on the side wall of the middle cover, and the control circuit on the circuit board is led out of the housing through the dovetail groove, and the alarm signal is transmitted by connecting the control circuit to the external alarm device. This structural setting is conducive to safe lead-in and wiring, avoids the control circuit from being exposed to the outside, is safe and reliable, and is easy to install. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation of the present invention or the technical solution in the prior art, the drawings required for use in the specific implementation or the description of the prior art are briefly introduced below.

[0024] Figure 1 A schematic diagram of the cross-sectional structure of a molded case circuit breaker provided by the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of the molded case circuit breaker of the present invention, and particularly shows the driving mechanism;

[0026] Figure 3 It is a schematic diagram of the separate structure of the driving mechanism and the limiting structure of the present invention;

[0027] Figure 4 for Figure 1 A partial enlarged structural schematic diagram of the driving mechanism shown;

[0028] Explanation of the reference numerals: 1-housing, 11-middle cover, 12-dovetail groove, 2-traction rod, 3-overload protection mechanism, 31-bimetallic strip, 32-adjusting screw, 4-limiting structure, 41-matching groove, 5-alarm trigger switch, 6-driving mechanism, 61-driving cam, 62-lock body, 63-key, 7-circuit board. DETAILED DESCRIPTION

[0029] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] Example 1

[0032] The present embodiment is described in detail below with reference to the accompanying drawings:

[0033] This embodiment provides Figure 1-4 A molded case circuit breaker with an adjustable overload alarm non-tripping function is shown, comprising a housing 1, a traction rod 2 arranged on the housing 1 and an overload protection mechanism 3, wherein when the overload protection mechanism 3 is triggered, the traction rod 2 is driven to trip and rotate, so as to realize the opening of the molded case circuit breaker, and further comprising:

[0034] a limiting structure 4, wherein the limiting structure 4 has a blocking position driven to move toward the traction rod to block the traction rod 2 from being released, and a separation position driven to move away from the traction rod 2 to release the blocking of the traction rod 2;

[0035] The alarm trigger switch 5 is arranged on the limiting structure 4 and is arranged opposite to the traction rod 2. When the traction rod 2 rotates in the tripping direction, the alarm trigger switch 5 is triggered. As can be seen from the above, when the limiting structure 4 moves to the blocking position, it drives the alarm trigger switch 5 close to the traction rod and restricts the traction rod 2 from tripping and rotating, so that the alarm trigger switch 5 is triggered when the traction rod 2 trips and rotates; and when the limiting structure 4 moves to the separation position, it drives the alarm trigger switch 5 away from the traction rod and releases the blocking restriction on the traction rod 2, so that the traction rod can trip and rotate normally.

[0036] In the above embodiment, when the user selects the overload alarm function, the limit structure 4 is driven to drive the alarm trigger switch 5 to move to the blocking position that blocks the traction rod 2 from tripping, thereby limiting the normal tripping of the traction rod. At this time, if an overload occurs in the line, the traction rod 2 is driven by the overload protection mechanism to trip and rotate, and the alarm trigger switch 5 is triggered before the tripping state is reached, so that the alarm trigger switch is turned on and an overload alarm signal is sent out, so that the staff can quickly troubleshoot the fault and the circuit breaker is still in working condition; when the user selects the overload tripping function, the limit structure 4 is driven to drive the alarm trigger switch 5 to move to the separation position that releases the blocking of the traction rod 2, so that the traction rod 2 is no longer blocked and restricted by the alarm trigger switch 5. At this time, if a fault current occurs in the line, the traction rod is triggered to trip normally to achieve the tripping and opening of the circuit breaker. The molded case circuit breaker adopting the present technical solution has a simple structure and can directly adjust the trigger distance between the overload protection mechanism 3 and the traction rod 2. The product inspection is relatively simple, and the first-time pass rate is greatly improved. It can freely switch between the overload alarm non-tripping function and the overload tripping function without replacing the product. It has a wide range of applications, is easy to operate, and provides customers with a variety of choices when using it.

[0037] In this embodiment, when the molded case circuit breaker selects the overload alarm non-tripping mode, the traction rod 2 is blocked by the alarm trigger switch and cannot continue to complete the tripping rotation, and the tripping function cannot be realized, thereby ensuring the normal operation of the line; when the overload tripping mode is selected, the driving mechanism 6 drives the motion switching component 4 and the alarm trigger switch 5 away from the traction rod 2, and the traction rod 2 can trip normally, and the tripping action between the overload protection mechanism and the traction rod can be tested. Therefore, the verification operation of the circuit breaker product is realized in this mode, the verification standards of each phase are consistent, the verification is convenient and the pass rate is high.

[0038] In this embodiment, if Figure 1As shown, in order to reliably realize the matching relationship between the limiting structure and the traction rod, the housing 1 is provided with a driving mechanism 6 for driving the limiting structure 4 to move toward or away from the traction rod 2. The driving mechanism 6 provides power for the limiting structure to switch movement, so that the limiting structure can switch movement between the blocking position and the separation position, ensuring that the molded case circuit breaker product can freely and reliably switch the overload alarm non-tripping function and the overload tripping function. The driving mechanism 6 can be manually mechanically operated or automatically mechanically operated.

[0039] According to the above embodiment, a mounting groove located on one side of the traction rod 2 is further preferably provided in the shell 1, and the limiting structure 4 is a push rod component movably arranged in the mounting groove, and the movement path of the push rod component partially overlaps with the movement path of the traction rod 2. The advantage of such a design is that the alarm trigger switch 5 is driven by the push rod component to be on the movement path of the traction rod, and can touch the alarm trigger switch 5 when the traction rod 2 is tripped and rotated. At the same time, the alarm trigger switch 5 blocks the tripping movement of the traction rod 2, thereby realizing the function of the circuit breaker product overload alarm not tripping, and the whole process does not affect the normal operation of the line.

[0040] Combine the following Figure 1 , Figure 3-4 The arrangement of the push rod components and the drive mechanism is described in detail:

[0041] In order to realize the linkage cooperation between the push rod component and the drive, a matching groove 41 is arranged on the push rod component, and the drive mechanism 6 has a drive cam 61 rotatably arranged in the matching groove 41. The drive mechanism 6 drives the drive cam 61 to rotate in the matching groove of the push rod component, and the protrusion of the drive cam 61 pushes against the groove walls at both ends of the matching groove 41 within its rotation stroke, and the groove walls at both ends of the matching groove 41 correspond to the two ends of the push rod component, thereby driving the push rod component to move in the installation groove towards or away from the traction rod 2, that is, to realize the alarm trigger switch approaching or away from the traction rod position. Through the above arrangement, the rotational motion of the drive cam is converted into the translational motion of the push rod component, and the matching transmission is reliable. Further preferably, reference Figure 1The alarm trigger switch 5 is arranged on one end of the push rod component facing the traction rod 2, and has a trigger button that cooperates with the traction rod 2. The alarm trigger switch 5 is preferably a micro switch. It can be seen that the distance movement between the push rod component and the traction rod is reduced to a reasonable design value. When an overload fault occurs in the line, the traction rod 2 will push the trigger button of the micro switch during the tripping rotation process. Conversely, the distance driven by the push rod component to the traction rod is set far enough to ensure that the traction rod 2 will not be blocked, and the product can achieve normal tripping. The design is reasonable, so that the molded case circuit breaker has both overload protection function and overload alarm non-tripping function, with diverse choices and safety and reliability.

[0042] As a preferred embodiment, Figure 2-4 As shown, the driving mechanism 6 comprises: a lock body 62 arranged on the housing 1 and a key 63 matched with the lock body, and the lock body 62 has a lock core arranged in linkage with the driving cam 61, and when the key 63 rotates, the lock core of the lock body 62 is driven to rotate. Further preferably, the push rod component and the driving cam 61 are arranged below the lock body 62, and a mounting hole is formed on the driving cam 61, and one end of the lock core extending downward from the lock body 62 is matched and installed in the mounting hole, and the linkage is maintained by a fixing component. With this structural setting, the key 63 is rotated forward or reversely by a certain angle to drive the lock core to rotate in linkage with the driving cam. In combination with the above, it can be known that the push rod component drives the alarm trigger switch 5 to move closer to or away from the traction rod 2, that is, the circuit breaker product can select the overload alarm non-tripping function or the overload tripping function by itself, and the adjustment operation is convenient, safe and reliable. It should be noted that the forward and reverse directions in this article only indicate that the rotation directions of a certain component are opposite in two rotations, and do not indicate the actual rotation direction.

[0043] In this embodiment, combined with Figure 3 As shown, a circuit board 7 connected to the alarm trigger switch 5 is provided on one end of the push rod component, and the alarm trigger switch is welded on the circuit board. Further preferably, the housing 1 includes a middle cover 11 on which the drive mechanism is installed, and a dovetail groove 12 connected to the mounting groove is provided on the side wall of the middle cover 11. The control circuit on the circuit board 7 is led out of the housing 1 through the dovetail groove 12, and the alarm signal transmission of the micro switch is realized by connecting the control circuit to the external alarm device. This structural setting is conducive to safe lead-in and wiring, and avoids the control circuit being exposed to the outside. In addition, the overload alarm function can be realized by replacing the middle cover of the ordinary molded case circuit breaker product. The entire installation process is also relatively simple and easy to operate, and the installation is convenient.

[0044] The following combination Figure 1 The setting method of the overload protection mechanism is described in detail:

[0045] The overload protection mechanism 3 includes a bimetallic strip 31 and a heat-conducting element for heating the bimetallic strip 31. The bimetallic strip 31 is arranged on the other side of the traction rod 2 relative to the push rod component. Therefore, when the bimetallic strip is bent by heat, it drives the traction rod to rotate toward one side of the micro switch, thereby triggering the micro switch to turn on.

[0046] Further preferably, one end of the bimetallic strip 31 is a fixed end fixedly matched with the heat-conducting element, and the other end is a free end bent by heat. The free end is provided with an adjusting screw 32 facing the traction rod 2. The distance between the bimetallic strip 31 and the traction rod 2 can be adjusted by rotating the adjusting screw by a certain stroke distance, so that the driving distance of the overload bending of the bimetallic strip 31 is shorter, the triggering is more timely, and the adjustment is convenient. As for calibration, as long as the distance between the micro switch and the traction rod is appropriate, the inspection of the product will be relatively simple, and the one-time pass rate will be greatly improved.

[0047] Combine the following Figure 1-2 The working principle of the overload alarm non-tripping function of the molded case circuit breaker is explained as follows: first, the key 63 is rotated forward, and the driving cam 61 pushes the matching groove 41 of the push rod component, thereby driving the push rod component to drive the alarm trigger switch 5 to move to the blocking position close to the traction rod 2, so that the alarm trigger switch is on the tripping rotation path of the traction rod 2. If an overload current appears in the line at this time, the bimetallic strip 31 bends and deforms to support the traction rod 2 to rotate toward the alarm trigger switch 5. The traction rod 2 will hit the alarm trigger switch before reaching the tripping state. The alarm trigger switch is turned on and outputs an alarm signal, so that the line maintenance personnel can quickly troubleshoot the fault with this alarm signal without affecting the normal operation of the line. Then, when the load is normal, the bimetallic strip is restored, the traction rod is restored to the locked state, the micro switch is released, and the alarm signal is released. If it is necessary to switch to the overload tripping function, in summary, it is only necessary to rotate the key in the opposite direction to drive the push rod component to drive the alarm trigger switch 5 to move away from the traction rod 2 to the separation position, so as to realize the normal tripping and opening action of the traction rod.

[0048] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A molded case circuit breaker with an adjustable overload alarm non-tripping function, comprising a housing (1), a traction rod (2) arranged on the housing (1), and an overload protection mechanism (3), wherein when the overload protection mechanism (3) is triggered, the traction rod (2) is driven to trip and rotate, so as to realize the opening of the molded case circuit breaker, characterized in that: Also includes: a limiting structure (4), the limiting structure (4) having a blocking position driven to move toward the traction rod to block the traction rod (2) from being released, and a separation position driven to move away from the traction rod (2) to release the blocking of the traction rod (2); An alarm trigger switch (5) is arranged on the limiting structure (4) and is arranged opposite to the traction rod (2), and the alarm trigger switch (5) is triggered when the traction rod (2) rotates in a tripping direction; The housing (1) is provided with a mounting groove located on one side of the traction rod (2); the limiting structure (4) is a push rod component movably arranged in the mounting groove; the movement path of the push rod component partially overlaps with the movement path of the traction rod (2).

2. The molded case circuit breaker with adjustable overload alarm and non-tripping function according to claim 1, characterized in that: The housing (1) is provided with a driving mechanism (6) for driving the limiting structure (4) to move towards or away from the traction rod (2).

3. The molded case circuit breaker with adjustable overload alarm and non-tripping function according to claim 2, characterized in that: The push rod component is provided with a matching groove (41), and the driving mechanism (6) has a driving cam (61) rotatably arranged in the matching groove (41) and driven by the driving mechanism, and at least one protrusion of the driving cam (61) pushes against the groove walls at both ends of the matching groove (41) within its rotation stroke, thereby driving the push rod component to move in the installation groove towards or away from the traction rod (2).

4. The molded case circuit breaker with adjustable overload alarm and non-tripping function according to claim 3, characterized in that: The driving mechanism (6) comprises: a lock body (62) arranged on the housing (1) and a key (63) matched with the lock body, and the lock body (62) has a lock core arranged in linkage with the driving cam (61), and when the key (63) is rotated, the lock core of the lock body (62) is driven to rotate.

5. The molded case circuit breaker with adjustable overload alarm and non-tripping function according to claim 4, characterized in that: The push rod component and the driving cam (61) are arranged below the lock body (62); a mounting hole is formed on the driving cam (61); one end of the lock core extending downward from the lock body (62) is mounted in the mounting hole.

6. The molded case circuit breaker with an adjustable overload alarm non-tripping function according to any one of claims 3 to 5, characterized in that: The alarm trigger switch (5) is arranged on one end of the push rod component facing the traction rod (2) and has a trigger button that cooperates with the traction rod. The alarm trigger switch (5) is a micro switch.

7. The molded case circuit breaker with adjustable overload alarm and non-tripping function according to claim 6, characterized in that: A circuit board (7) connected to the alarm trigger switch (5) is arranged on one end of the push rod component, and the housing (1) includes a middle cover (11) on which the drive mechanism is installed, and a dovetail groove (12) is provided on the side wall of the middle cover (11), and the control circuit on the circuit board is led out of the housing (1) through the dovetail groove (12).

8. The molded case circuit breaker with adjustable overload alarm and non-tripping function according to claim 6, characterized in that: The overload protection mechanism (3) comprises a bimetallic strip (31) and a heat-conducting element for heating the bimetallic strip (31); the bimetallic strip (31) is arranged on the other side of the traction rod (2) relative to the push rod component.

9. The molded case circuit breaker with adjustable overload alarm and non-tripping function according to claim 8, characterized in that: One end of the bimetallic strip (31) is a fixed end fixedly matched with the heat-conducting element, and the other end is a free end bent by heat, and an adjusting screw (32) facing the traction rod (2) is provided on the free end.

Images