Short-circuit delay release and circuit breaker
By using an electromagnetic tripper in the circuit breaker, using two springs with a length difference of d to provide resistance, the compact structure and flexible adjustment capability of the short-circuit delay tripper is achieved, and the problems of large size and high cost in the prior art are solved.
Patent Information
- Application Number
- CN202421294637.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-07
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2034-06-07
AI Technical Summary
The existing circuit breaker short-circuit short-delay tripper with selective protection has problems of large size and high cost, and multiple spring specifications need to be configured under different current specifications, which is inconvenient to manage.
采用包括线圈骨架、线圈、动铁芯和静铁芯的电磁脱扣器,通过设置两个长度差为d的弹簧,其中一个弹簧套设在另一弹簧的外侧,动铁芯在线圈通电时驱动移动,弹簧提供阻力以实现延时动作和短路延时时间的调整。
The compact structure of the short-circuit delay tripper is realized, which avoids the increase in the size of the electromagnetic tripper along the spring axis direction, reduces the difficulty of subsequent assembly, and facilitates the adjustment of the delay action setting value and the short-circuit delay time.
Smart Images
Figure CN222867603U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of low-voltage electrical appliances, in particular to a short-circuit time-delay releaser and a circuit breaker. Background Art
[0002] Circuit breakers are widely used in low-voltage power distribution systems and are often used to protect the safety of power supply circuits. Circuit breakers are generally composed of a contact system, an arc extinguishing system, an operating mechanism, and an overcurrent protection device. Under normal working conditions, the operating mechanism uses a transmission mechanism such as a lever to keep the contact system closed or open to connect and disconnect the power line. When an overcurrent fault occurs, the overcurrent protection device operates to trip the operating mechanism and quickly cut off the overcurrent. Among them, the most commonly used structures for overcurrent protection are magnetic releases and thermal releases.
[0003] In recent years, with the development of terminal systems, circuit breakers with selective protection are increasingly widely used. In terminal power distribution systems, users generally set up multi-level circuit breaker protection. When a fault current appears on the load side, and the fault short-circuit current exceeds the short-circuit instantaneous action value of the lower circuit breaker, and also exceeds the short-circuit instantaneous action value of the upper circuit breaker, the upper and lower circuit breakers will trip at the same time, or trip across levels. At this time, the circuit breaker with selective protection will realize selective protection as the upper circuit breaker, and adopt a short-circuit short-delay release.
[0004] The short-circuit short-time delay release of the circuit breaker with selective protection is divided into electronic and mechanical types, but both the electronic release and the mechanical release have the disadvantages of large size and high cost.
[0005] Although there are optimized solenoid types on the market that use two moving iron cores and two instantaneous springs, when there are many product current specifications, many corresponding spring specifications need to be configured, which is not convenient for production management. Utility Model Content
[0006] The purpose of the utility model is to overcome at least one defect of the prior art and provide a short-circuit delay release.
[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0008] A short-circuit delay release comprises an electromagnetic release, the electromagnetic release comprises a coil frame, a coil wound on the outside of the coil frame, and a moving iron core and a static iron core arranged inside the coil frame. When the coil is energized, the moving iron core is driven to move from an initial position to the static iron core. Two springs are arranged between the static iron core and the moving iron core. Both ends of the two springs are used to cooperate with the static iron core and the moving iron core. One of the springs is sleeved on the outside of the other spring. When the moving iron core is in the initial position, the length difference between the two springs is d. The two springs are respectively a first spring and a second spring, wherein the length of the first spring is greater than that of the second spring. When the moving iron core is in the initial position, the first spring is in contact with the moving iron core to provide a first resistance. After the moving iron core moves a distance d under the drive of the coil, the second spring provides a second resistance for the moving iron core. At this time, the first spring and the second spring provide resistance for the moving iron core at the same time.
[0009] Preferably, the two ends of the first spring are respectively connected to the moving iron core and the static iron core; one end of the second spring is connected to the moving iron core, and the end of the second spring away from the moving iron core is spaced apart from the static iron core, and the distance between the second spring and the static iron core is d; or, one end of the second spring is connected to the static iron core, and the end of the second spring away from the static iron core is spaced apart from the moving iron core, and the distance between the moving iron core and the second spring is d.
[0010] Preferably, the diameter of the first spring is greater than the diameter of the second spring, the second spring is arranged on the inner side of the first spring, the two ends of the first spring are respectively connected to the moving iron core and the static iron core, one end of the second spring is connected to the moving iron core, and the end of the second spring away from the moving iron core is spaced apart from the static iron core.
[0011] Preferably, the two springs are an integrated composite spring, one ends of the two springs are flush and connected, and the distance between the other ends of the two springs is d.
[0012] Preferably, the moving iron core is provided with a first contact surface, a connecting column for connecting a push rod is provided in the center of the first contact surface, the static iron core is provided with a core groove for accommodating a first spring and a second spring, a side wall of the core groove is provided with a second contact surface opposite to the first contact surface, two ends of the first spring respectively abut against the first contact surface and the second contact surface, a through hole for passing the push rod is provided in the middle of the second contact surface, one end of the push rod is located on the inner side of the second spring, and the other end of the push rod passes through the static iron core from the through hole.
[0013] Preferably, the connecting column is respectively provided with a first limiting ring and a second limiting ring, the push rod is provided with a fixing groove for inserting the connecting column and the first limiting ring, the fixing groove is provided with a limiting groove for clamping the upper limit fit of the first limiting ring column, and the end of the second spring is sleeved on the second limiting ring for the upper limit fit.
[0014] Preferably, a first limiting ring is provided on the connecting column, and the push rod is provided with a fixing groove for inserting the connecting column and the first limiting ring, and the fixing groove is provided with a limiting groove for clamping the upper limit fit on the first limiting ring column, and a third limiting ring is provided on the outer side of the push rod, and the end of the second spring is sleeved on the third limiting ring for upper limit fit.
[0015] Preferably, the second limiting ring is provided with a transition surface on the side away from the moving iron core, and the transition surface is arranged at an oblique angle to the spring.
[0016] Preferably, the second limiting ring and the third limiting ring are provided with a transition surface on the side away from the moving iron core, and the transition surface is arranged at an oblique angle to the spring.
[0017] Preferably, the diameter of the first spring is 1.3 to 1.7 times the diameter of the second spring.
[0018] The short-circuit delay release of this embodiment can not only adjust the delay action setting value and the short-circuit delay time by setting two springs with a length difference of d, but also one of the springs is sleeved on the outside of the other spring, so there is no need to set the two springs along the axial direction, avoiding increasing the size of the electromagnetic release along the spring axial direction, making the electromagnetic release more compact and smaller in size.
[0019] In addition, the end of the second spring is sleeved on the second limiting ring for limiting engagement, and by installing the second spring on the moving iron core, the difficulty of subsequent assembly of the electromagnetic release can be reduced.
[0020] This embodiment also provides a circuit breaker, which includes a housing and the short-circuit short-time delay release.
[0021] The circuit breaker of this embodiment includes a housing and the short-circuit short-delay release. Through the short-circuit short-delay release, not only can the delay action setting value and the short-circuit delay time be conveniently adjusted, but also the size of the electromagnetic release along the spring axis direction can be avoided from increasing, thereby making the structure of the circuit breaker more compact. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a structural schematic diagram of the housing of the utility model;
[0023] Figure 2 It is a structural schematic diagram of the initial position of the moving iron core of the utility model;
[0024] Figure 3 It is a structural schematic diagram of the utility model when the movable iron core is in contact with the second spring;
[0025] Figure 4 This is a schematic diagram of the structure of the utility model after the moving iron core moves into place;
[0026] Figure 5 It is a schematic diagram of the structure of a composite spring in which two springs are integrated into one body of the utility model;
[0027] Figure 6 This is a schematic diagram of the cooperation between the moving iron core and the ejector rod of the utility model in the first embodiment;
[0028] Figure 7 This is a schematic structural diagram of the movable iron core of the utility model in the first embodiment;
[0029] Figure 8 It is a schematic structural diagram of the push rod of the utility model in the first embodiment;
[0030] Fig. 9 This is a schematic diagram of the cooperation between the moving iron core and the ejector rod in the second embodiment of the utility model;
[0031] Fig.10 This is a schematic structural diagram of the movable iron core of the utility model in the second embodiment;
[0032] Fig.11 This is a schematic structural diagram of the push rod of the utility model in the second embodiment;
[0033] In the figure, coil 1; moving iron core 2; stationary iron core 3; spring 4; first spring 41; second spring 42; first contact surface 21; push rod 22; connecting column 23; iron core groove 31; second contact surface 32; first limiting ring 24; second limiting ring 25; fixing groove 27; limiting groove 28; third limiting ring 29; transition surface 20; coil skeleton 52. DETAILED DESCRIPTION
[0034] The following embodiments are given in conjunction with the accompanying drawings to further illustrate the specific implementation of the short-circuit delay release of the utility model. The short-circuit delay release of the utility model is not limited to the description of the following embodiments.
[0035] The circuit breaker of this embodiment includes a shell and a moving contact, a stationary contact, an arc extinguishing mechanism, an operating mechanism and a handle respectively arranged in the shell. The moving contact and the stationary contact are connected to the circuit through a first terminal and a second terminal at both ends of the shell respectively. The handle drives the moving contact to move through the operating mechanism, so that the moving contact and the stationary contact are in contact and separated, thereby connecting and disconnecting the circuit connected by the moving contact and the stationary contact. The arc extinguishing mechanism is used to extinguish the arc generated by the moving contact and the stationary contact. The arc extinguishing mechanism is provided with a plurality of grids, and the arc is cut into a plurality of small segments by the plurality of grids and then extinguished.
[0036] The operating mechanism includes a contact support and an energy storage spring connected to the contact support. The contact support is respectively provided with a rotatable jump buckle and a lock buckle, and the jump buckle and the lock buckle are snap-fitted. A connecting rod is provided between the jump buckle and the handle, and the two ends of the connecting rod are respectively rotatably connected to the handle and the jump buckle, so that the handle is connected to the jump buckle through the connecting rod, and the contact support is connected to the moving contact. When the jump buckle and the lock buckle are snap-fitted, the lock buckle locks the jump buckle and the contact support. When the handle pushes the jump buckle through the connecting rod, the jump buckle can drive the contact support to rotate. When the handle rotates in two opposite directions respectively, the contact support can drive the moving contact to contact and separate from the static contact. When the moving contact contacts the static contact, the contact support compresses the energy storage spring and is locked by the handle.
[0037] The shell is provided with a short-circuit releaser and an overload protection mechanism for triggering a trip and a lock release. The short-circuit releaser and the overload protection mechanism can respectively trigger the lock when the corresponding short-circuit current and overload current appear in the connected line, and release the snap fit between the lock and the trip. At this time, the handle loses the lock on the contact support, so that the energy storage spring is released. When the energy storage spring is released, it drives the contact support to rotate, so that the moving contact is separated from the static contact, thereby realizing the short-circuit protection and overload protection functions.
[0038] The overload protection mechanism includes a bimetallic strip connected between the moving contact and the second terminal. When the overload current flowing through the bimetallic strip meets the action condition, the bimetallic strip bends due to temperature rise, thereby directly or indirectly triggering the lock and trip release.
[0039] like Figure 2 As shown, the short-circuit delay release includes an electromagnetic release, which includes a coil 1 and a moving iron core 2 and a static iron core 3 respectively arranged in the coil 1. When the coil 1 is energized, it drives the moving iron core 2 to move from an initial position to the static iron core 3, directly or indirectly triggering the lock and trip release.
[0040] refer to Figure 2 Usually, the short-circuit release is an electromagnetic release, including a coil 1, a static iron core 3, a moving iron core 2 and a spring located between the static iron core 3 and the moving iron core 2. When the coil 1 is energized, it drives the moving iron core 2 to overcome the elastic force of the spring and move from the initial position to the static iron core 3. The coil 1 is connected between the static contact and the first terminal. When the short-circuit current flowing through the coil 1 meets the preset delay action setting value, the huge short-circuit current causes the electromagnetic force generated by the coil 1 to drive the moving iron core 2 to move from the initial position. The moving iron core 2 moves a certain distance to the trigger position according to the preset short-circuit delay time, and then directly or indirectly triggers the lock and jump release. This is the prior art in the field and will not be repeated here.
[0041] An improvement of the present embodiment is that the short-circuit releaser of the present embodiment is a short-circuit short-delay releaser, comprising a coil 1, a static iron core 3, a moving iron core 2 and two springs 4 located between the static iron core 3 and the moving iron core 2, one of the two springs 4 being sleeved on the outside of the other spring 4, and the length difference between the two springs 4 when the moving iron core 2 is in the initial position is d, the two springs 4 are respectively a first spring 41 and a second spring 42, the length of the first spring 41 is greater than that of the second spring 42, and when the moving iron core 2 is in the initial position, the first spring 41 is in contact with the moving iron core 2 to provide a first resistance, and after the moving iron core 2 moves a distance d under the drive of the coil 1, the second spring 42 provides a second resistance for the moving iron core 2 to achieve a short-circuit short delay, and the moving iron core 2 overcomes the first resistance of the first spring 41 and the second resistance of the second spring 42 and moves toward the static iron core 3, and it is obvious that d must be greater than 0.
[0042] The circuit breaker of this embodiment includes a housing and the short-circuit short-delay release. Through the short-circuit short-delay release, not only can the delay action setting value and the short-circuit delay time be conveniently adjusted, but also the size of the electromagnetic release along the spring axis direction can be avoided from increasing, thereby making the structure of the circuit breaker more compact.
[0043] It should be noted that the diameter of the first spring 41 may be larger than that of the second spring 42 , and the first spring 41 may be sleeved outside the second spring 42 ; or the diameter of the second spring 42 may be larger than that of the first spring 41 , and the second spring 42 may be sleeved outside the first spring 41 .
[0044] When a short circuit fault occurs, the huge short circuit current causes the electromagnetic force generated by the coil 1 to drive the moving iron core 2 to move from the initial position. After the moving iron core 2 overcomes the first resistance of the first spring 41 and moves a distance of d, it contacts the second spring 42, overcomes the first resistance of the first spring 41 and the second resistance of the second spring 42 and continues to move. The first spring 41 is used to determine the delay action setting value, that is, to adjust the short circuit current value that triggers the moving iron core 2 to move. The first spring 41 limits the moving iron core 2 at the initial position of the moving iron core 2 to keep the moving iron core 2 stationary. Under the drive of the coil 1, the moving iron core 2 needs to overcome the first resistance of the first spring 41 before starting to move in the direction close to the second spring 42. The second spring 42 is used to reduce the acceleration of the moving iron core 2 and to adjust the short-circuit delay time. After the moving iron core 2 moves a distance d, the second spring 42 begins to apply a second resistance to the moving iron core 2, that is, at this time, the first spring 41 and the second spring 42 simultaneously provide resistance to the moving iron core 2. Driven by the coil 1, the moving iron core 2 needs to overcome the combined force of the first spring 41 and the second spring 42 to continue moving. On the basis of the unchanged moving stroke of the moving iron core 2, the time for the moving iron core 2 to move to the end of the stroke is changed, that is, the time to move to the trigger position that can trigger the lock and the jump buckle to release, thereby achieving the adjustment of the short-circuit delay time.
[0045] The short-circuit delay release of this embodiment is provided with two springs 4. When the moving iron core 2 is in the initial position, the length difference between the two springs 4 is d. This not only enables the adjustment of the delay action setting value and the short-circuit delay time, but also one of the springs 4 is sleeved on the outside of the other spring 4. It is not necessary to arrange the two springs 4 along the axial direction, thereby avoiding increasing the size of the electromagnetic release along the axial direction of the spring 4, and making the electromagnetic release more compact and smaller in size.
[0046] like Figure 2 As shown, the short-circuit time-delay release of this embodiment also includes a yoke arranged on the housing, and a cylindrical coil frame 52 arranged on the yoke, the coil 1 is wound on the outside of the coil frame 52, and a static iron core 3 and a moving iron core 2 are arranged on the inside of the coil frame 52, and the coil 1 is used to attract the moving iron core 2 to move close to the static iron core 3. Figure 2 As shown, the two springs 4 of this embodiment are respectively a first spring 41 and a second spring 42. In this embodiment, the diameter of the first spring 41 is greater than the diameter of the second spring 42, and the length of the first spring 41 is greater than the second spring 42. The second spring 42 is arranged on the inner side of the first spring 41. The two ends of the first spring 41 are respectively connected to the moving iron core 2 and the static iron core 3. One end of the second spring 42 is connected to the moving iron core 2. The end of the second spring 42 away from the moving iron core 2 is spaced from the static iron core 3. The distance between the second spring 42 and the static iron core 3 is d, that is, the length difference between the two springs is d. By installing the second spring 42 on the moving iron core 2, subsequent assembly can be facilitated. Preferably, the diameter of the first spring 41 is 1.3 to 1.7 times the diameter of the second spring 42. It can be understood that the second spring 42 can also be connected to the static iron core 3, and the end of the second spring 42 away from the static iron core 3 is spaced apart from the moving iron core 2, and the distance between the moving iron core 2 and the second spring 42 is d. The moving iron core 2 overcomes the first resistance of the first spring 41 under the drive of the coil 1, moves a distance of d, and then contacts the second spring 42, and overcomes the combined force of the first spring 41 and the second spring 42. In addition, the diameter of the first spring 41 can also be smaller than the diameter of the second spring 42, and the first spring 41 is arranged on the inner side of the second spring 42, which can also reduce the size of the first spring 41 and the second spring 42 along the axial direction.
[0047] In another embodiment, the two springs 4 are an integrated composite spring, one end of the two springs 4 are flush and connected, the distance between the other ends of the two springs 4 is d, and the second spring 42 does not need to be installed separately, which has the characteristic of easy assembly.
[0048] like Figure 2 As shown, Figure 2is the initial position of the moving iron core 2, the difference between the length of the first spring 41 and the length of the second spring 42 is d, the initial distance between the moving iron core 2 and the static iron core 3 is L1, when the current in the coil 1 does not reach the delay action setting value, the driving force of the coil 1 on the moving iron core 2 is less than the resistance of the first spring 41, and the moving iron core 2 does not move;
[0049] When the current in the coil 1 reaches the delayed action setting value and is less than the instantaneous action setting value, the driving force of the coil 1 on the moving iron core 2 is less than the resistance of the first spring 41, and the moving iron core 2 does not move;
[0050] like Figure 2-3 As shown, the driving force of the coil 1 on the moving iron core 2 is greater than the resistance of the first spring 41, and the moving iron core 2 moves toward the stationary iron core 3 under the drive of the coil 1;
[0051] like Figure 3 As shown, after the moving iron core 2 travels the distance d, it drives the second spring 42 to contact the stationary iron core 3. The acceleration of the moving iron core 2 decreases under the resistance of the second spring 42, so that the time for the moving iron core 2 to travel the remaining distance L2 becomes longer.
[0052] like Figure 4 As shown, the moving iron core 2 continues to move until it drives the ejector rod to hit the operating mechanism to unlock it, thereby controlling the short-circuit delay time.
[0053] like Figure 1 As shown, the short-circuit delay release is arranged in the middle of the shell, and the short-circuit delay release is arranged between the handle and the arc extinguishing mechanism, which is not shown in the figure, and is located on one side of the operating mechanism. The moving iron core 2 is provided with a first contact surface 21, and a connecting column 23 for connecting the top rod 22 is provided in the center of the first contact surface 21. The static iron core 3 is provided with an iron core groove 31 for accommodating the first spring 41 and the second spring 42. The side wall of the iron core groove 31 is provided with a second contact surface 32 opposite to the first contact surface 21. The two ends of the first spring 41 respectively abut on the first contact surface 21 and the second contact surface 32. The middle part of the second contact surface 32 is provided with a through hole for passing the top rod 22. One end of the top rod 22 is located on the inner side of the second spring 42, and the other end of the top rod 22 passes through the static iron core 3 from the through hole to cooperate with the operating mechanism.
[0054] like Figure 6-8 A first embodiment in which the first spring 41 and the second spring 42 are connected to the moving iron core 2 is shown. The push rod 22 passes through the first spring 41, the second spring 42 and the stationary iron core 3 respectively, and is used to trigger the unlocking of the operating mechanism. In this embodiment, the second spring 42 is connected to the connecting column 23 of the moving iron core 2.
[0055] In this embodiment, the connecting column 23 is respectively provided with a first limit ring 24 and a second limit ring 25, and the push rod 22 is provided with a fixing groove 27 for inserting the connecting column 23 and the first limit ring 24, and the fixing groove 27 is provided with a limit groove 28 for clamping the upper limit fit of the first limit ring 24 column, and the end of the second spring 42 is sleeved on the second limit ring 25 for the upper limit fit, and the second spring 42 is installed on the moving iron core 2, which can reduce the subsequent assembly difficulty of the electromagnetic release.
[0056] like Figure 9-11 In the second embodiment shown, the second spring 42 is connected to the push rod 22, and the second limiting ring 25 in the previous embodiment is not provided on the connecting column 23. A first limiting ring 24 is provided on the connecting column 23 of this embodiment, and the push rod 22 is provided with a fixing groove 27 for inserting the connecting column 23 and the first limiting ring 24. A limiting groove 28 for clamping the first limiting ring 24 on the column is provided in the fixing groove 27. A third limiting ring 29 is provided on the outer side of the push rod 22, and the end of the second spring 42 is sleeved on the third limiting ring 29 for upper limit cooperation.
[0057] Preferably, the second limiting ring 25 or the third limiting ring 29 is respectively provided with a transition surface 20 on the side away from the moving iron core 2, and the transition surface 20 is arranged at an oblique angle to the spring, which can facilitate the spring to be clamped on the second limiting ring 25 and the third limiting ring 29, thereby reducing the difficulty of assembly.
[0058] In other embodiments, an independent part may be provided on the moving iron core 2, and the first spring 41 and the second spring 42 may be connected to the independent part.
[0059] It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc. indicate directions or positional relationships based on directions or positional relationships shown in the drawings, or directions or positional relationships that are usually placed when in use, and are only for the convenience of description, rather than indicating that the device or element referred to must have a specific direction, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish descriptions, and cannot be understood as indicating relative importance.
[0060] The above contents are further detailed descriptions of the present invention in combination with specific preferred implementations, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.
Claims
1. A short-circuit time-delay release, comprising an electromagnetic release, the electromagnetic release comprising a coil frame (52), a coil (1) wound on the outside of the coil frame (52), and a moving iron core (2) and a stationary iron core (3) arranged inside the coil frame (52), the coil (1) driving the moving iron core (2) to move from an initial position to the stationary iron core (3) when power is supplied, characterized in that: Two springs (4) are arranged between the static iron core (3) and the moving iron core (2), and both ends of the two springs (4) are used to cooperate with the static iron core (3) and the moving iron core (2), one spring (4) is sleeved on the outside of the other spring (4), and when the moving iron core (2) is at an initial position, the length difference between the two springs (4) is d, and the two springs (4) are respectively a first spring (41) and a second spring (42), wherein the length of the first spring (41) is greater than that of the second spring (42), and when the moving iron core (2) is at the initial position, the first spring (41) is in contact with the moving iron core (2) to provide a first resistance, and after the moving iron core (2) moves a distance d under the drive of the coil (1), the second spring (42) provides a second resistance for the moving iron core (2), and at this time, the first spring (41) and the second spring (42) simultaneously provide resistance for the moving iron core (2).
2. The short-circuit time-delay release according to claim 1, characterized in that: The two ends of the first spring (41) are respectively connected to the moving iron core (2) and the static iron core (3); one end of the second spring (42) is connected to the moving iron core (2), and the end of the second spring (42) away from the moving iron core (2) is spaced apart from the static iron core (3), and the distance between the second spring (42) and the static iron core (3) is d; or, one end of the second spring (42) is connected to the static iron core (3), and the end of the second spring (42) away from the static iron core (3) is spaced apart from the moving iron core (2), and the distance between the moving iron core (2) and the second spring (42) is d.
3. The short-circuit time-delay release according to claim 1, characterized in that: The diameter of the first spring (41) is greater than the diameter of the second spring (42); the second spring (42) is arranged on the inner side of the first spring (41); the two ends of the first spring (41) are respectively connected to the moving iron core (2) and the static iron core (3); one end of the second spring (42) is connected to the moving iron core (2); and one end of the second spring (42) away from the moving iron core (2) is spaced apart from the static iron core (3).
4. The short-circuit time-delay release according to claim 1, characterized in that: The two springs (4) are an integrated composite spring, one end of the two springs (4) are flush and connected, and the distance between the other ends of the two springs (4) is d.
5. The short-circuit time-delay release according to claim 3, characterized in that: The movable iron core (2) is provided with a first contact surface (21), a connecting column (23) for connecting a push rod (22) is provided at the center of the first contact surface (21), the static iron core (3) is provided with an iron core groove (31) for accommodating a first spring (41) and a second spring (42), a side wall of the iron core groove (31) is provided with a second contact surface (32) opposite to the first contact surface (21), two ends of the first spring (41) respectively abut against the first contact surface (21) and the second contact surface (32), a through hole for passing the push rod (22) is provided in the middle of the second contact surface (32), one end of the push rod (22) is located on the inner side of the second spring (42), and the other end of the push rod (22) passes through the static iron core (3) from the through hole.
6. The short-circuit time-delay release according to claim 5, characterized in that: The connecting column (23) is provided with a first limiting ring (24) and a second limiting ring (25), respectively; the push rod (22) is provided with a fixing groove (27) for inserting the connecting column (23) and the first limiting ring (24); the fixing groove (27) is provided with a limiting groove (28) for clamping the first limiting ring (24) column to fit the upper limit position; the end of the second spring (42) is sleeved on the second limiting ring (25) to fit the upper limit position.
7. The short-circuit time-delay release according to claim 5, characterized in that: The connecting column (23) is provided with a first limiting ring (24), the push rod (22) is provided with a fixing groove (27) for inserting the connecting column (23) and the first limiting ring (24), the fixing groove (27) is provided with a limiting groove (28) for clamping the first limiting ring (24) column to fit the upper limit position, the outer side of the push rod (22) is provided with a third limiting ring (29), and the end of the second spring (42) is sleeved on the third limiting ring (29) to fit the upper limit position.
8. The short-circuit time-delay release according to claim 6, characterized in that: The second limiting ring (25) is provided with a transition surface (20) on the side away from the moving iron core (2), and the transition surface (20) is arranged at an oblique angle with the spring (4).
9. The short-circuit time-delay release according to claim 7, characterized in that: The third limiting ring (29) is provided with a transition surface (20) on the side away from the moving iron core (2), and the transition surface (20) is arranged at an oblique angle with the spring (4).
10. The short-circuit time-delay release according to claim 3, characterized in that: The diameter of the first spring (41) is 1.3 to 1.7 times the diameter of the second spring (42).
11. A circuit breaker, characterized in that: It comprises a housing and the short-circuit delay release as claimed in any one of claims 1 to 10.