Improved contact reliability for latching closure

Abstract

The application discloses an excitation closer with improved contact reliability, which comprises a shell, an electronic ignition tube, a piston, a telescopic limiting device and a contact system arranged in the shell; the contact system comprises a movable contact plate, a first static contact plate and a second static contact plate which are arranged at an insulating interval, and the telescopic movable contact plate is arranged corresponding to the first static contact plate and the second static contact plate; the piston supported by a supporting spring is connected with the movable contact plate; the limiting device in a compressed state is arranged on at least one side of a displacement path of the piston, and the initial position and the terminal position of the piston are limited. The excitation closer has the advantages of high current carrying capacity, high contact and reliable contact.

Description

Technical Field

[0001] This invention relates to the fields of power control and electric vehicles, and in particular to an excitation closure that can connect a backup circuit via low-voltage drive after the main circuit is disconnected due to an electrical fault. Background Technology

[0002] Currently, the protection measures for DC circuit systems (such as electric vehicles) consist of fuses and contactors. Contactors primarily handle the connection and disconnection of rated loads and currents below that, while fuses handle short-circuit currents. When a short-circuit current occurs in the main circuit, the fuse blows, permanently disconnecting the main circuit without replacing the fuse, causing inconvenience to users. Furthermore, existing circuit closers typically connect the circuit by inserting the conductive part into the break point with an interference fit, or by achieving closure through the displacement of the moving conductor and contact with the stationary conductor. Because the contact pressure is very low after the moving conductor makes conductive contact with the stationary conductor, the current-carrying capacity is weak. Alternatively, the moving conductor may contact the stationary conductor under impact, but the rebound force during contact can cause the moving conductor to bounce, or the electrostatic repulsion force may cause the moving conductor to move away from the stationary conductor, leading to poor contact. Under high current conditions, this can even result in circuit disconnection or explosion. Summary of the Invention

[0003] The purpose of this invention is to provide an excitation closure device that improves contact reliability. By limiting the position of the moving contact after closure through a limiting device, the moving contact is ensured to make reliable contact with the stationary contact plate. This improves the contact pressure and current carrying capacity of the contact, while preventing the moving contact from breaking off from the stationary contact plate under the action of electric repulsion force under high current.

[0004] To achieve the above objectives, the technical solution of the present invention is an excitation closure device that improves contact reliability, comprising a housing, wherein an electronic ignition tube, a piston, a retractable limiting device, and a contact system are disposed within the housing;

[0005] The contact system includes a movable contact plate, a first stationary contact plate, and a second stationary contact plate. The first stationary contact plate and the second stationary contact plate are insulated from each other and pass through the housing. The movable contact plate is disposed in the housing in an insulated manner corresponding to the first stationary contact plate and the second stationary contact plate. The movable contact plate is retractable.

[0006] The piston is connected to the movable contact plate, and the piston is supported by a support spring disposed in the housing;

[0007] The limiting device is disposed on at least one side of the piston displacement path. When the piston is in the initial position, the piston abuts against the limiting device, and the limiting device is in a compressed state.

[0008] When the electronic ignition tube releases driving force according to the received trigger signal, the driving force drives the piston to displace against the elastic force of the support spring. The piston, along with the moving contact plate, makes conductive contact with the first stationary contact plate and the second stationary contact plate. When the moving contact plate makes conductive contact with the first stationary contact plate and the second stationary contact plate, the piston disengages from the limiting device. The limiting device extends out and is located in the piston displacement path, limiting the piston's termination position.

[0009] Preferably, the limiting device includes a retractable first insertion component. When the piston is in the initial position, the piston abuts against the first insertion component. When the piston displaces and disengages from the first insertion component, the first insertion component passes through the displacement path of the piston and is inserted into the insertion hole in the housing on the other side of the piston displacement path.

[0010] Preferably, the insertion hole is a snap-fit ​​hole, and the end of the first insertion component facing the piston is provided with a snap-fit ​​structure. When the piston is displaced and disengaged from the first insertion component, the first insertion component passes through the displacement path of the piston and is inserted into the insertion hole in a snap-fit ​​connection manner.

[0011] Preferably, the limiting device includes a retractable first insertion component and a retractable second insertion component, which are respectively disposed in the outer shell on opposite sides of the piston. When the piston is in the initial position, the piston abuts against the first insertion component and the second insertion component respectively. When the piston displaces and disengages from the contact with the first insertion component and the second insertion component, the first insertion component and the second insertion component extend towards each other and are connected in an insertion manner, passing through the piston displacement path and defining the end position of the piston.

[0012] Preferably, the first connector assembly includes a first snap-fit, a first spring, and a first connector connected in sequence; the second connector assembly includes a second snap-fit, a second spring, and a second connector connected in sequence; the first snap-fit ​​and the second snap-fit ​​are fixedly connected to the housing by snap-fit ​​connection, and the first connector and the second connector are located on opposite sides of the piston displacement path. When the piston is in the initial position, the piston abuts against the first connector and the second connector, and the first spring and the second spring are in a compressed state; when the piston displaces from the first connector and the second connector, under the elastic force of the first spring and the second spring, the first connector and the second connector extend towards each other and are connected by a connector.

[0013] Preferably, it further includes a contact support assembly, wherein the movable contact plate is retractably disposed on the contact support assembly, and the piston is fixedly connected to the contact support assembly.

[0014] Preferably, the contact support assembly includes a support base, a contact support member, and a push rod; the contact support member has a U-shaped structure, the bottom of the U-shaped structure is a flat structure, and the open end of the U-shaped structure of the contact support member is movably connected to the opposite sides of the support base; a movable contact plate and a compressed contact spring are disposed between the contact support member and the support base, one end of the contact spring abuts against the support base, and the other end abuts against the movable contact plate, so that the movable contact plate abuts against the contact support member; one end of the push rod is fixed on the support base, and the other end is connected to the piston, and the support spring is sleeved on the push rod between the support base and the piston.

[0015] Preferably, the U-shaped structure of the contact support has locking holes on both sides of the open end, and the support base has buckles on opposite sides. When the buckles of the support base are engaged in the locking holes of the contact support, space is reserved in the locking holes for the buckles to move in the piston displacement direction.

[0016] Preferably, the support spring is a disc spring.

[0017] Preferably, the first and second stationary contact plates are bent at one end within the housing in a cushioning manner, ensuring that the moving contact plate contacts the first and second stationary contact plates in a surface-to-surface contact manner.

[0018] Preferably, the first and second stationary contact plates are in an inverted U-shaped structure at one end of the housing.

[0019] The excitation closure device of the present invention adopts a plate-shaped stationary contact plate and a moving contact plate. At the same time, the piston termination position is limited by a limiting device, so that the moving contact plate and the stationary contact plate are in close contact, which increases the contact pressure of the contact and increases the contact area. Compared with the traditional excitation closure device, it has the ability of high current carrying capacity, fast connection (i.e., high connection) and low contact resistance.

[0020] The excitation closure is used in the standby circuit and is connected in parallel with the protective fuse of the main circuit. After the fuse blows and the main circuit is disconnected, when the main circuit eliminates the abnormal situation and has the ability to conduct again, the excitation closure closes to conduct the standby circuit, so that the main circuit can be conducted, avoiding the need to replace the fuse connected in series in the main circuit. Attached Figure Description

[0021] Figure 1 This is a circuit diagram showing the excitation closure connected in parallel in the main circuit as a backup circuit.

[0022] Figure 2 This is a circuit diagram showing a second fuse connected in series in the backup circuit.

[0023] Figure 3 This is a schematic diagram of the external structure of the excitation closure.

[0024] Figure 4 This is a schematic diagram of the excitation closure.

[0025] Figure 5 This is a schematic diagram of the exploded structure of the contact support component.

[0026] Figure Labels

[0027] First fuse 100, circuit protection device 101, excitation closure device 102, second fuse 103, electronic ignition tube 1, piston 2, first pair of plugs 3, first spring 4, first snap fastener 5, third spring 6, contact spring 7, moving contact plate 8, first stationary contact plate 9, bottom cover 10, second stationary contact plate 11, lower housing 12, contact support assembly 13, upper housing 14, second snap fastener 15, second spring 16, second pair of plugs 17, insulating boss 18, guide sleeve 19, plug groove 20, contact support 131, support base 132, push rod 133, snap fastener 134, and snap hole 135. Detailed Implementation

[0028] The present invention provides an excitation closure device for improving contact reliability, comprising a housing, within which are disposed an electronic ignition tube, a piston, a retractable limiting device, and a contact system;

[0029] The contact system includes a moving contact plate, a first stationary contact plate, and a second stationary contact plate. The first stationary contact plate and the second stationary contact plate are insulated from each other and pass through the housing. The moving contact plate is disposed in the housing in an insulated manner corresponding to the first stationary contact plate and the second stationary contact plate. The moving contact plate is retractable.

[0030] The piston is connected to the moving contact plate, and the piston is supported by a support spring installed in the housing.

[0031] The limiting device is provided on at least one side of the piston displacement path. When the piston is in the initial position, the piston abuts against the limiting device, and the limiting device is in a compressed state.

[0032] When the electronic ignition tube releases driving force according to the received trigger signal, the driving force drives the piston to overcome the elastic force of the support spring and displace. The piston, along with the moving contact plate, makes conductive contact with the first stationary contact plate and the second stationary contact plate. When the moving contact plate makes conductive contact with the first stationary contact plate and the second stationary contact plate, the piston disengages from the limiting device. The limiting device extends out and is located in the piston displacement path, limiting the piston's termination position.

[0033] The following describes preferred embodiments in detail with reference to the accompanying drawings. The directional terms used are for reference only and do not constitute a limitation on the technical solution of this invention.

[0034] The circuit diagram of the excitation closure device used in this invention is shown below. Figure 1 The first fuse 100 is connected in series with the circuit protection device 101 in the main circuit. The excitation closure 102 is connected in parallel with the first fuse 100 and in series with the circuit protection device 101. The circuit containing the excitation closure 102 is the backup circuit of the main circuit. The circuit protection device 101 is a device for circuit protection such as a contactor or circuit breaker.

[0035] Under normal operating conditions or during minor fault current, the excitation closure opens, and the current flows through the first fuse 100 and the circuit protection device 101. The main circuit is switched on and off by the closing and opening of the circuit protection device 101. When an overcurrent occurs, the first fuse 100 blows to protect the main circuit. When the fault in the main circuit is cleared, the excitation closure turns on according to the received trigger signal, and the current in the main circuit flows through the excitation closure 101 and the circuit protection device 101.

[0036] Therefore, the parallel circuit containing the excitation closure 102 serves as a backup circuit after the fuse blows. When the fuse blows, there is no need to replace it; simply closing the excitation closure 102 directly connects the backup circuit. To ensure the excitation closure also provides circuit protection after connecting the backup circuit, a second fuse 103 is connected in series in the backup circuit containing the excitation closure. (See [reference]). Figure 2 .

[0037] Excitation closure 102, see Figures 3 to 4 It includes an outer casing, and an electronic ignition tube 1, a piston 2, a first pair of plug-in assemblies 3, a first spring 3, a first buckle 5, a third spring 6, a contact spring 7, a moving contact plate 8, a first stationary contact plate 9, a bottom cover 10, a second stationary contact plate 11, a lower housing 12, a contact support assembly 13, an upper housing 14, a second buckle 15, a second spring 16, a second pair of plug-in assemblies 17, a guide sleeve 19, a contact support 131, a support base 132, a push rod 133, a buckle 134, a locking hole 135, and a plug-in slot 20.

[0038] In this embodiment, the outer shell is formed by an upper shell 14, a lower shell 12, and a bottom cover 10 joined together. The upper shell, lower shell, and bottom cover are connected and fixed by screws. The upper shell 14 has a first chamber for accommodating the electronic ignition tube 1, the piston 2, and the third spring 6. Channels for accommodating limiting devices are provided on opposite sides of the first chamber in the upper shell 14. The lower shell 12 has a second chamber for accommodating the contact system and the contact support assembly 13, and the second chamber is sealed. A guide sleeve 19 is provided at one end of the lower shell 12 facing the upper shell 14, and the guide sleeve 19 is integrally formed with the lower shell 12.

[0039] The contact system includes a first stationary contact plate 9, a second stationary contact plate 11, and a moving contact plate 8. The bottom cover 10 has opposing and insulated receiving grooves formed on its end face within the second cavity, with an insulating boss 18 formed between the two receiving grooves. The first stationary contact plate 9 and the second stationary contact plate 11 are respectively fixedly disposed in the opposing receiving grooves. One end of each of the first and second stationary contact plates extends outside the housing and serves as a terminal for the excitation closure. The other end, in contact with the moving contact plate 8, is bent in an inverted U-shape. The bent end is higher than the insulating boss 18 and parallel to the moving contact plate 8 to ensure maximum contact area when the moving contact plate 8 contacts the stationary contact plate. The inverted U-shaped bend has a certain elastic deformation capacity, i.e., a certain buffering performance. When the moving contact plate 8 contacts the stationary contact plate, the impact energy of the moving contact plate 8 is buffered by the inverted U-shaped bend.

[0040] Contact support assembly 13, see Figure 5 The system includes a contact support 131, a bracket base 132, and a push rod 133. The bracket base 132 is located in a guide sleeve 19 within the lower housing 12. When the bracket base 132 is displaced, it moves along the guide sleeve 19. An annular groove for accommodating the contact spring 7 is provided on the end face of the bracket base 132 facing the bottom cover 10. Supporting protrusions protruding from the end faces of the annular groove are provided on the opposite sides of the annular groove. Buckles 134 are provided on the outer sides of the supporting protrusions. The contact support 131 has a U-shaped structure with a flat bottom. Snap holes 135 are provided on the two wings of the open end of the U-shaped structure corresponding to the buckles 134. The contact support 131 is mounted on the bracket base 132, and the buckles 134 of the bracket base 132 are engaged in the snap holes 135 of the contact support 131, thus movably mounting the contact support 131 on the bracket base 132. The movable contact plate 8 is movably disposed at the bottom of the U-shaped structure. The contact spring 7 is disposed between the contact support 131 and the bracket base 132. One end of the contact spring 7 abuts against the annular groove of the bracket base 132, and the other end abuts against the protrusion on the movable contact plate 8. The contact spring 7 is compressed, pressing the movable contact plate 8 against the bottom of the U-shaped structure of the contact support 131. After the snap-fit ​​134 engages with the snap-fit ​​hole 135, space is maintained in the snap-fit ​​hole 135 for displacement of the contact support 131 relative to the bracket base 132. The movable contact plate 8 is positioned towards the first stationary contact plate 9 and the second stationary contact plate 11, and is located below the guide sleeve 19.

[0041] The push rod 133 is fixedly connected to the bracket base 132 at one end, and the other end passes through the lower housing and enters the first cavity in the upper housing, where it is threadedly connected to the piston 2. The piston 2 is either fitted into the first cavity or in a sealed contact manner. When the sealed contact manner is used, a sealing ring is provided on the outer circumferential surface of the piston 2 in contact with the first cavity.

[0042] The electronic ignition tube 1 is located at the top of the first cavity and seals the first cavity. The electronic ignition tube 1 is a gas generating device that can ignite according to the received trigger signal and release high-pressure gas as driving force.

[0043] A third spring 6 is sleeved on the push rod 133 between the piston 2 and the lower housing 12. In this embodiment, the third spring 6 is a plurality of disc springs, which support the piston 2 and the contact support assembly 13. A limiting step is provided in the first cavity. The end of the piston 2 facing the electronic ignition tube 1 abuts against the limiting step under the elastic force of the third spring 6, thus limiting the initial position of the piston 2.

[0044] The limiting device includes a retractable first plug-in assembly and a retractable second plug-in assembly. Channels communicating with the first cavity are provided on opposite sides of the first cavity. The first plug-in assembly and the second plug-in assembly are respectively disposed in the channels on both sides of the first cavity. The first and second plug-in assemblies are located on opposite sides of the piston 2's displacement path. At the piston 2's initial position, the first and second plug-in assemblies are located on opposite sides of the piston 2, isolating the first and second plug-in assemblies so that they are located in their respective channels without obstructing the piston 2's displacement. When the piston 2 displaces, the first and second plug-in assemblies lose the piston 2's obstruction and extend towards each other into the first cavity, connecting in a plug-in manner, thus forming a limiting device in the first cavity that prevents the piston 2 from retracting.

[0045] The specific structures of the first plug-in component and the retractable second plug-in component are as follows: the first plug-in component includes a first pair of plugs 3, a first spring 4, and a first buckle 5; the second plug-in component includes a second buckle 15, a second spring 16, and a second pair of plugs 17.

[0046] The channel structure of the first and second plug-in components is set: one end of the upper housing 14 is shaped like an inverted T. The first buckle 5 and the second buckle 15 are respectively locked in the through hole of the inverted T. One end of the first spring 4 is fixedly connected to the first buckle 5, and the other end is fixedly connected to the first plug-in 3. One end of the second spring 16 is fixedly connected to the second buckle 15, and the other end is fixedly connected to the second plug-in 17. In the initial position, the first spring 4 and the second spring 16 are respectively in a compressed state. The first plug-in 3 and the second plug-in 17 are respectively located on opposite sides of the piston 2 and are in contact with the piston 2.

[0047] The second pair of plugs 17 has a insertion groove 20 on its end face facing the piston 2. When the piston 2 moves, and the first pair of plugs 3 and the second pair of plugs 17 lose contact with the piston 2, under the action of the first spring 4 and the second spring 16, the first pair of plugs 3 and the second pair of plugs 17 extend towards each other, and the first pair of plugs 3 inserts into the insertion groove 20 of the second pair of plugs 17, thus connecting the first pair of plugs 3 and the second pair of plugs 17 and limiting the final displacement of the piston 2. To ensure a firm connection between the first pair of plugs 3 and the second pair of plugs 17, the first spring 4 and the second spring 16 are always in a compressed state, ensuring a reliable connection between the first pair of plugs 3 and the second pair of plugs 17.

[0048] Working principle:

[0049] When the electronic ignition tube 1 activates according to the received trigger signal, it releases the driving force, driving the piston 2 to overcome the elastic force of the third spring 6 and move along the first cavity. The piston 2, through the push rod 133, moves the contact support assembly and the moving contact plate 8 toward the first stationary contact plate 9 and the second stationary contact plate 11, making the moving contact plate 8 make conductive contact with the first stationary contact plate 9 and the second stationary contact plate 11. After making conductive contact, the piston 2, along with the bracket base 132, continues to move. The bracket base 132, with the buckle 134, moves in the locking hole 135 on the contact support 131 until it stops moving at the lower edge of the locking hole 135. The contact spring 7 then releases its pressure. The support base 132 and the moving contact plate 8 are compressed in two directions. Under the elastic force of the contact spring 7 with maximum compression, the moving contact plate 8 is in close contact with the first and second stationary contact plates, increasing the contact pressure, increasing the contact area, and decreasing the contact resistance. When the piston 2 stops moving, the first pair of plugs 3 and the second pair of plugs 17 are plugged in and connected, forming a limitation on the termination position of the piston 2 in the first cavity, preventing the piston 2 from retracting under the combined action of the third spring 6 and the contact spring 7, ensuring that the buckle 134 of the support base 132 abuts against the bottom of the contact support force hole 135, thereby ensuring that the contact system is in close contact.

[0050] In the above structure, the limiting device is provided with a first connector assembly and a second connector assembly. In some embodiments, only one first connector assembly may be provided, and the housing of the second connector assembly is set as a connector hole. When the piston is in the initial position, the piston abuts against the first connector assembly, causing the first connector assembly to be in a compressed state. When the piston displaces and leaves contact with the first connector assembly, the first connector assembly passes through the piston's displacement path and inserts into the connector hole on the other side of the piston's displacement path. For a more reliable connection, the connector hole is set as a snap-fit ​​structure, and the end of the first connector of the first connector assembly facing the piston is set as a snap-fit ​​structure. When the first connector passes through the piston's displacement path and inserts into the connector hole, the first connector assembly is inserted into the connector hole in a snap-fit ​​connection manner.

Claims

1. An excitation closure device for improving contact reliability, characterized in that, It includes a housing, within which are disposed an electronic ignition tube, a piston, a retractable limiting device, and a contact system; The contact system includes a movable contact plate, a first stationary contact plate, and a second stationary contact plate. The first stationary contact plate and the second stationary contact plate are insulated from each other and pass through the housing. The movable contact plate is disposed in the housing in an insulated manner corresponding to the first stationary contact plate and the second stationary contact plate. The movable contact plate is retractable. The piston is connected to the movable contact plate, and the piston is supported by a support spring disposed in the housing; The limiting device is disposed on at least one side of the piston displacement path. When the piston is in the initial position, the piston abuts against the limiting device, and the limiting device is in a compressed state. When the electronic ignition tube releases driving force according to the received trigger signal, the driving force drives the piston to displace against the elastic force of the support spring. The piston, along with the moving contact plate, makes conductive contact with the first stationary contact plate and the second stationary contact plate. When the moving contact plate makes conductive contact with the first stationary contact plate and the second stationary contact plate, the piston disengages from the limiting device. The limiting device extends out and is located in the piston displacement path, limiting the piston's termination position.

2. The excitation closure device according to claim 1, characterized in that, The limiting device includes a retractable first plug-in assembly. When the piston is in the initial position, the piston abuts against the first plug-in assembly. When the piston displaces and disengages from the first plug-in assembly, the first plug-in assembly passes through the displacement path of the piston and is inserted into a plug-in hole in the housing on the other side of the piston displacement path.

3. The excitation closure device according to claim 2, characterized in that, The insertion hole is a snap-fit ​​hole. The end of the first insertion component facing the piston is provided with a snap-fit ​​structure. When the piston is displaced and disengaged from the contact with the first insertion component, the first insertion component passes through the displacement path of the piston and is inserted into the insertion hole in a snap-fit ​​connection manner.

4. The excitation closure device according to claim 1, characterized in that, The limiting device includes a retractable first plug-in component and a retractable second plug-in component. The first plug-in component and the second plug-in component are respectively disposed in the outer shell on opposite sides of the piston. When the piston is in the initial position, the piston abuts against the first plug-in component and the second plug-in component respectively. When the piston displaces and disengages from the contact with the first plug-in component and the second plug-in component, the first plug-in component and the second plug-in component extend towards each other and are connected in a plugging manner, passing through the piston displacement path and limiting the end position of the piston.

5. The excitation closure device according to claim 4, characterized in that, The first plug-in assembly includes a first snap-fit, a first spring, and a first connector connected in sequence; the second plug-in assembly includes a second snap-fit, a second spring, and a second connector connected in sequence; the first snap-fit ​​and the second snap-fit ​​are fixedly connected to the outer shell by snap-fit ​​connection, and the first connector and the second connector are located on opposite sides of the piston displacement path. When the piston is in the initial position, the piston abuts against the first connector and the second connector respectively, and the first spring and the second spring are in a compressed state; when the piston displaces from the first connector and the second connector, under the elastic force of the first spring and the second spring, the first connector and the second connector extend towards each other and are connected by a plug-in connection.

6. The excitation closure device according to claim 1, characterized in that, It also includes a contact support assembly, wherein the movable contact plate is retractably disposed on the contact support assembly, and the piston is fixedly connected to the contact support assembly.

7. The excitation closure device according to claim 6, characterized in that, The contact support assembly includes a support base, a contact support member, and a push rod. The contact support member has a U-shaped structure with a flat bottom. The open end of the U-shaped structure is movably connected to the opposite sides of the support base. A movable contact plate and a compressed contact spring are disposed between the contact support member and the support base. One end of the contact spring abuts against the support base, and the other end abuts against the movable contact plate, causing the movable contact plate to abut against the contact support member. One end of the push rod is fixed to the support base, and the other end is connected to the piston. The support spring is sleeved on the push rod between the support base and the piston.

8. The excitation closure device according to claim 7, characterized in that, The U-shaped structure of the contact support has two wing-shaped openings on its two sides, and the support base has buckles on opposite sides. When the buckles of the support base are engaged in the buckles of the contact support, space is reserved in the buckles in the piston displacement direction for the buckles to move.

9. The excitation closure device according to claim 7, characterized in that, The support spring is a disc spring.

10. The excitation closure device according to claim 1, characterized in that, The first and second stationary contact plates are bent at one end within the housing in a cushioning manner, ensuring that the moving contact plate contacts the first and second stationary contact plates in a surface-to-surface contact manner.

11. The excitation closure device according to claim 10, characterized in that, The first and second stationary contact plates are located at one end of the housing in an inverted U-shape.

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