Load switch for intelligent electric meter

Abstract

The invention relates to a load switch for an intelligent electric meter, which comprises a shell, a null line assembly, a live wire assembly, a driving mechanism, a closing mechanism and an isolation mechanism are arranged in the shell, the driving mechanism controls the opening and closing of the closing mechanism, the isolation mechanism is used for isolating the null line assembly and the live wire assembly, and the live wire assembly comprises a first connecting plate and a second connecting plate which are separated from each other. The switching-on mechanism comprises a first rotating shaft arranged on the shell, a rotating shaft support arranged on the first rotating shaft, a moving contact arranged on the rotating shaft support, a cam assembly driving the rotating shaft support to rotate around the first rotating shaft, a reset piece limiting rotation of the rotating shaft support, and a static contact arranged on the second connecting plate. The moving contact is electrically connected with the first connecting plate. According to the invention, the cam assembly maintains the abutting of the moving contact and the static contact, the abutting stability of the moving contact and the static contact is improved, when the load circuit is disconnected, the cam assembly and the reset member cooperate to realize the rapid separation of the moving contact and the static contact, the generation of electric arc is reduced, and the safety is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of load switches, and in particular to a load switch for a smart electric meter. Background Art

[0002] Smart meter built-in load switches are widely used in various power management systems, especially in scenarios that require remote control and management. For example, in smart grids, power suppliers can use smart meter built-in load switches to achieve real-time monitoring and remote control of user power usage behavior, thereby improving the efficiency and safety of power management.

[0003] However, the load switch has the following problems when in use: when the load switch disconnects the load circuit, the disengagement speed of the moving contact and the static contact cannot meet the requirements, and the arc between the moving contact and the static contact cannot be extinguished quickly, resulting in burning of the moving and static contacts.

[0004] Therefore, there is a need for a load switch for a smart meter that can achieve rapid separation of a moving contact from a stationary contact, reduce arc generation, improve safety, and has a simple structure and low cost. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides a load switch for a smart electric meter.

[0006] The technical solution of the present invention is as follows:

[0007] A load switch for a smart meter, comprising a housing, wherein a neutral line assembly, a live line assembly, a driving mechanism, a closing mechanism and an isolating mechanism are arranged in the housing, wherein the driving mechanism controls the opening and closing of the closing mechanism, wherein the isolating mechanism is used to isolate the neutral line assembly from the live line assembly, wherein the live line assembly comprises a first coupling plate and a second coupling plate which are separated, wherein the closing mechanism comprises a first rotating shaft arranged on the housing, a rotating shaft bracket arranged on the first rotating shaft, a moving contact arranged on the rotating shaft bracket, a cam assembly driving the rotating shaft bracket to rotate around the first rotating shaft, a reset member limiting the rotation of the rotating shaft bracket, and a static contact arranged on the second coupling plate, wherein the moving contact is electrically connected to the first coupling plate;

[0008] When the switch is closed, the driving mechanism drives the cam assembly to rotate in a first direction, the cam assembly applies a driving force to the rotating shaft bracket and drives the rotating shaft bracket to rotate, the moving contact moves toward the static contact and abuts against the static contact, and the rotating shaft bracket remains stationary;

[0009] When opening the switch, the driving mechanism drives the cam assembly to rotate in the second direction, the cam assembly releases the driving force on the rotating shaft bracket, the reset member applies a pulling force to the rotating shaft bracket, and the moving contact moves in a direction away from the static contact to separate the moving contact from the static contact.

[0010] As a further improvement of the present invention, the driving mechanism includes a control board arranged in the housing, a motor controlled by the control board, a worm and a worm wheel arranged at a driving end of the motor, and the worm wheel is engaged with the cam assembly.

[0011] As a further improvement of the present invention, the cam assembly includes a second rotating shaft arranged in the housing, a gear portion arranged on the second rotating shaft, and a cam portion arranged on the gear portion, the gear portion is meshed with the worm gear, and when the switch is closed, the cam portion abuts against the rotating shaft bracket and applies a driving force to the rotating shaft bracket.

[0012] As a further improvement of the present invention, the rotating shaft bracket includes a main body rotating around the first rotating shaft, and the main body is provided with a connecting hole and a connecting part, the connecting hole is used to be connected to the reset member, and the connecting part abuts against the cam assembly and bears the driving force from the cam assembly.

[0013] As a further improvement of the present invention, there are multiple moving contacts and multiple stationary contacts, and the number of the moving contacts is the same as that of the stationary contacts and they correspond one to one.

[0014] As a further improvement of the present invention, an energy storage component is provided between the moving contact and the rotating shaft bracket.

[0015] As a further improvement of the present invention, the isolation mechanism includes a zero-sequence current transformer arranged on the shell and an isolation bracket arranged in the middle of the zero-sequence current transformer, the neutral line assembly includes a third connecting plate, the second connecting plate and the third connecting plate both pass through the zero-sequence current transformer, and the isolation bracket isolates the second connecting plate and the third connecting plate.

[0016] As a further improvement of the present invention, a first through hole is provided on the isolation bracket, a second through hole and a third through hole are respectively provided on both sides of the first through hole, the second connecting plate passes through the second through hole, and the third connecting plate passes through the third through hole.

[0017] As a further improvement of the present invention, the first end of the isolation bracket is provided with a blocking portion extending away from the first through hole, and the blocking portion limits the first end from passing through the zero-sequence current transformer; the second end of the isolation bracket is provided with at least a first limiting portion, and the second connecting plate and / or the third connecting plate is provided with a second limiting portion, and the first limiting portion corresponds one-to-one to the second limiting portion.

[0018] As a further improvement of the present invention, an arc extinguishing mechanism is provided at the position where the moving contact abuts against the static contact.

[0019] According to the present invention of the above scheme, the beneficial effects of the present invention are:

[0020] 1. The present invention applies a driving force to the rotating shaft bracket through the cam assembly to realize and maintain the abutment between the moving contact and the static contact, thereby improving the stability of the abutment between the two. When the load circuit is disconnected, the cam assembly releases the driving force on the rotating shaft bracket, and under the action of the reset member, the moving contact and the static contact can be quickly separated, thereby reducing the generation of arcs and improving safety;

[0021] 2. The present invention arranges the second connecting plate and the third connecting plate in the second through hole and the third through hole respectively, so that the distance of the isolation gap between the second connecting plate and the third connecting plate can be stabilized, so that the isolation effect is reliable and stable, and by adding the first through hole, the contact between the neutral wire assembly and the live wire assembly through solid conduction can be reduced, so as to further improve the reliability and stability of the isolation effect;

[0022] 3. The present invention has a simple overall structure, is easy to operate and has low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of the present invention;

[0024] Figure 2 It is a structural schematic diagram of the closing mechanism of the present invention when the closing mechanism is closed;

[0025] Figure 3 It is a schematic diagram of the structure of the closing mechanism of the present invention when the closing mechanism is opened;

[0026] Figure 4 It is a schematic structural diagram of the first angle of the rotating shaft support of the present invention;

[0027] Figure 5 It is a schematic diagram of the structure of the second angle of the rotating shaft support of the present invention;

[0028] Figure 6 It is a structural schematic diagram of the isolation mechanism of the present invention;

[0029] Figure 7 This is a schematic diagram of the structure of the isolation bracket of the present invention at a first angle;

[0030] Figure 8 is a schematic structural diagram of the isolation bracket of the present invention at a second angle;

[0031] Fig. 9 is a schematic structural diagram of the second connecting plate of the present invention;

[0032] Fig.10 It is a schematic structural diagram of the shell surface of the present invention;

[0033] Fig.11 It is a structural schematic diagram of the first connecting plate of the present invention.

[0034] In the figure: 1, shell; 21, first connecting plate; 211, L end; 212, JP3 terminal; 213, JP4 terminal; 22, second connecting plate; 23, second limiting part; 30, first rotating shaft; 31, rotating shaft bracket; 311, body; 312, connecting hole; 313, connecting part; 314, slot; 32, moving contact; 33, reset member; 34, static contact; 35, second rotating shaft; 36, gear part; 37, cam part; 38, micro switch; 39, torsion spring; 41, control board; 42, motor; 43, worm; 44, worm wheel; 51, zero-sequence current transformer; 52, isolation bracket; 53, first through hole; 54, second through hole; 55, third through hole; 56, opening; 57, blocking part; 58, first limiting part; 61, third connecting plate; 7, arc extinguishing mechanism. DETAILED DESCRIPTION

[0035] 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.

[0036] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0037] 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 connection 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. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0038] See also Figure 1 The present invention provides a load switch for a smart meter, comprising a housing 1, wherein a neutral line component, a live line component, a driving mechanism, a closing mechanism and an isolating mechanism are arranged in the housing 1, wherein the driving mechanism controls the opening and closing of the closing mechanism, and the isolating mechanism is used to isolate the neutral line component from the live line component, wherein the live line component comprises a separated first coupling plate 21 and a second coupling plate 22, and wherein the closing mechanism comprises a first rotating shaft 30 arranged on the housing 1, a rotating shaft bracket 31 arranged on the first rotating shaft 30, a moving contact 32 arranged on the rotating shaft bracket 31, a cam component driving the rotating shaft bracket 31 to rotate around the first rotating shaft 30, a reset member 33 limiting the rotation of the rotating shaft bracket 31, and a static contact 34 arranged on the second coupling plate 22, wherein the moving contact 32 is electrically connected to the first coupling plate 21;

[0039] See also Figure 2 When the switch is closed, the driving mechanism drives the cam assembly to rotate in the first direction, the cam assembly applies a driving force to the shaft bracket 31 and drives the shaft bracket 31 to rotate, the moving contact 32 moves toward the static contact 34 and abuts against the static contact 34, and the shaft bracket 31 remains stationary;

[0040] See also Figure 3 When opening the switch, the driving mechanism drives the cam assembly to rotate in the second direction, the cam assembly releases the driving force on the rotating shaft bracket 31, the reset member 33 applies a pulling force to the rotating shaft bracket 31, and the moving contact 32 moves in a direction away from the static contact 34 to separate the moving contact 32 from the static contact 34. Preferably, the disconnection distance between the moving contact 32 and the static contact 34 reaches about 7 mm.

[0041] The present invention applies a driving force to the rotating shaft bracket 31 through the cam assembly to achieve and maintain the abutment between the moving contact 32 and the static contact 34, thereby improving the stability of the abutment between the two. When the load circuit is disconnected, the cam assembly releases the driving force on the rotating shaft bracket 31, and under the action of the reset member 33, the moving contact 32 and the static contact 34 can be quickly separated, reducing the generation of arcs and improving safety. The overall structure is simple, the operation is convenient, and the cost is low.

[0042] As an embodiment of the present invention, the driving mechanism includes a control board 41 arranged in the shell 1, a motor 42 controlled by the control board 41, a worm 43 and a worm wheel 44 arranged at the driving end of the motor 42, the worm wheel 44 is engaged with the cam assembly, and the control board 41 is connected to the external signal. The structure of the worm wheel 44 and the worm 43 can reduce the number of parts of the reduction system and simplify the structure to a certain extent. When the fee is in arrears, the control board 41 receives the signal and controls the motor 42 to move, and drives the cam assembly to rotate through the worm 43 and the worm wheel 44 to separate the moving contact 32 from the static contact 34 to achieve the purpose of opening the switch. After paying, the control board 41 also receives the signal and controls the motor 42 to move, and drives the cam assembly to rotate through the worm 43 and the worm wheel 44 to achieve the abutment of the moving contact 32 from the static contact 34 to achieve the purpose of closing the switch.

[0043] As an embodiment of the present invention, the cam assembly includes a second rotating shaft 35 arranged in the housing 1, a gear portion 36 arranged on the second rotating shaft 35, and a cam portion 37 arranged on the gear portion 36. The gear portion 36 is meshed with a driving mechanism in the load switch, and the driving mechanism drives the gear portion 36 to rotate. When the switch is closed, the cam portion 37 abuts against the rotating shaft bracket 31 and applies a driving force to the rotating shaft bracket 31, so that the moving contact 32 and the static contact 34 abut and remain stationary, thereby ensuring stable contact between the moving contact 32 and the static contact 34. When the load circuit is disconnected, the driving mechanism drives the gear portion 36 to rotate in the opposite direction, the cam portion 37 releases the driving force on the shaft bracket 31, and drives the shaft bracket 31 to rotate further under the action of the reset member 33, thereby realizing the rapid separation of the moving contact 32 and the stationary contact 34. Through the structure combining the gear portion 36 and the cam portion 37, it is only necessary to control the rotation of the gear portion 36 to realize the rotation control of the shaft bracket 31 and the switching of the abutment or separation between the moving contact 32 and the stationary contact 34. The overall structure is simple and easy to control.

[0044] As an embodiment of the present invention, the center of the gear portion 36 coincides with the center of the cam portion 37, ensuring that the gear portion 36 and the cam portion 37 rotate only at the same center when rotating, which can effectively reduce the overall occupied space and improve space utilization.

[0045] See also Figure 4 and Figure 5As an embodiment of the present invention, the shaft bracket 31 includes a body 311 that rotates around the first shaft 30. The body 311 is provided with a connecting hole 312 and a connecting portion 313. The connecting hole 312 is used to connect with the reset member 33. The reset member 33 transmits the force to the body 311 through the connecting hole 312 to realize the overall rotation of the shaft bracket 31. When the switch is closed, the connecting portion 313 abuts against the cam assembly and bears the driving force from the cam assembly, that is, the driving force of the cam assembly is greater than the force of the reset member 33, so that the moving contact 32 and the static contact 34 are abutted. When the load is disconnected, the When the cam assembly is in the process of moving, the cam assembly releases the driving force on the connecting portion 313, and the shaft bracket 31 rotates only under the force of the reset member 33, thereby realizing the separation between the moving contact 32 and the stationary contact 34. The connecting hole 312 and the connecting portion 313 are respectively located on both sides of the shaft bracket 31, so that the force from the reset member 33 and the driving force from the cam assembly are mutually reverse forces, and the rotation direction of the shaft bracket 31 is controlled by the magnitude relationship between the two forces, thereby realizing the abutment or separation between the moving contact 32 and the stationary contact 34. The overall structure is simple and easy to control, which improves practicality.

[0046] As an embodiment of the present invention, the load switch cam structure also includes a limiter, which limits the rotation of the cam assembly to avoid unnecessary damage caused by endless rotation of the cam assembly, that is, when the load circuit needs to be closed and the moving contact 32 abuts against the static contact 34, or when the load circuit needs to be disconnected and the moving contact 32 is separated from the static contact 34, the limiter sends a limit signal to stop the cam assembly from moving. Preferably, the limiter is a micro switch 38 arranged on the housing 1, and the cam assembly rotates to press or release the micro switch 38, that is, when the load circuit needs to be closed, the drive mechanism drives the cam assembly to rotate to achieve the abutment of the moving contact 32 and the static contact 34, and press the micro switch 38, and the micro switch 38 transmits a signal to the drive mechanism to stop the cam assembly from continuing to rotate. When the load circuit needs to be disconnected, the drive mechanism drives the cam assembly to rotate to achieve the separation of the moving contact 32 and the static contact 34, and releases the micro switch 38, and the drive mechanism stops the cam assembly from continuing to rotate.

[0047] As an embodiment of the present invention, there are multiple moving contacts 32 and multiple stationary contacts 34. The number of moving contacts 32 and the stationary contacts 34 are the same and correspond one to one. The use of a multi-contact structure can effectively reduce the contact resistance between the moving contact 32 and the stationary contact 34, reduce temperature rise, increase the service life of the moving contact 32 and the stationary contact 34, and improve the overall safety of use.

[0048] As an embodiment of the present invention, an energy storage component is provided between the moving contact 32 and the rotating shaft bracket 31. When the moving contact 32 abuts against the static contact 34, the energy storage component stores a certain amount of energy. When the load circuit is disconnected, the energy stored in the energy storage component is released, thereby promoting the rapid separation of the moving contact 32 and the static contact 34. Preferably, the energy storage component is a torsion spring 39, and a slot 314 is provided on the rotating shaft bracket 31. The first end of the torsion spring 39 is arranged on the rotating shaft bracket 31, and the second end of the torsion spring 39 abuts against the moving contact 32 and presses the moving contact 32 into the slot 314. Before the moving contact 32 abuts against the static contact 34, the torsion spring 39 presses the moving contact The head 32 is restricted in the slot 314, so that the relative position of the moving contact 32 and the shaft bracket 31 is fixed. When the moving contact 32 abuts against the static contact 34, the shaft bracket 31 continues to rotate, and the moving contact 32 cannot continue to rotate with the shaft bracket 31, causing the torsion spring 39 to be stretched to store energy. When the load circuit is disconnected, the energy stored in the torsion spring 39 is released, so that the moving contact 32 and the static contact 34 are quickly separated. Under the action of the reset member 33, the moving contact 32 and the static contact 34 are further separated, which effectively improves the separation speed of the moving contact 32 and the static contact 34, reduces the generation of arcs, and improves safety.

[0049] As an embodiment of the present invention, the reset member 33 is a tension spring, one end of which is arranged on the housing 1, and the other end of the tension spring is connected to the shaft bracket 31. When the load circuit is closed, the tension of the tension spring on the shaft bracket 31 is less than the driving force of the cam assembly on the shaft bracket 31, and the tension spring is stretched. When the load circuit is disconnected, the cam assembly releases the driving force on the shaft bracket 31, and the tension spring contracts. Under the tension of the tension spring on the shaft bracket 31, the shaft bracket 31 rotates, thereby realizing the separation of the moving contact 32 and the static contact 34.

[0050] See also Figure 6-8, as an embodiment of the present invention, the isolation mechanism includes a zero-sequence current transformer 51 arranged on the housing 1 and an isolation bracket 52 arranged in the middle of the zero-sequence current transformer 51, the zero-line assembly includes a third connecting plate 61, the second connecting plate 22 and the third connecting plate 61 both pass through the zero-sequence current transformer 51, and the isolation bracket 52 isolates the second connecting plate 22 from the third connecting plate 61. Preferably, the isolation bracket 52 is provided with a first through hole 53, and the two sides of the first through hole 53 are respectively provided with a second through hole 54 and a third through hole 55, and the second connecting plate 22 passes through the second through hole. Hole 54, the third connecting plate 61 passes through the third through hole 55, and the second connecting plate 22 and the third connecting plate 61 are respectively arranged in the second through hole 54 and the third through hole 55, so that the distance of the isolation gap between the second connecting plate 22 and the third connecting plate 61 can be stable, so that the overall creepage distance is stable, and the reliability and stability of the isolation effect are improved. By adding the first through hole 53, the contact between the neutral wire component and the live wire component through solid conduction can be reduced, and the reliability and stability of the isolation effect can be further improved. The overall structure is simple, the installation is convenient, and the use cost is low.

[0051] As an embodiment of the present invention, the second through hole 54 and the third through hole 55 can adopt the following two structures:

[0052] Structure 1: The second through hole 54 and the third through hole 55 are both full holes. During installation, the second connecting plate 22 and the third connecting plate 61 can be inserted into the second through hole 54 and the third through hole 55 in advance. After the second connecting plate 22 and the third connecting plate 61 are assembled with the isolation bracket 52, they are inserted into the zero-sequence current transformer 51 as a whole to complete the assembly;

[0053] Structure 2: The second through hole 54 and / or the third through hole 55 are half holes. Preferably, the second through hole 54 and the third through hole 55 are both half holes. During installation, the second connecting plate 22 and the third connecting plate 61 are preferentially inserted into the zero-sequence current transformer 51, and then the isolation bracket 52 is inserted into the zero-sequence current transformer 51. Finally, the second connecting plate 22 and the third connecting plate 61 are adjusted according to the positions of the second through hole 54 and the third through hole 55 on the isolation bracket 52 to complete the assembly.

[0054] The present invention adopts structure 2. Compared with structure 1, structure 2 can reduce half of the hole wall occupation of the second through hole 54 and the third through hole 55, and convert it into the occupied space of the second through hole 54 and the third through hole 55, effectively expanding the second through hole 54 and the third through hole 55, so that the thickness of the second connecting plate 22 and the third connecting plate 61 allowed to pass through the second through hole 54 and the third through hole 55 is increased, which can effectively increase the overall allowable working current and improve the overall application range, or expand the first through hole 53, so that the interval between the second connecting plate 22 and the third connecting plate 61 becomes larger, thereby improving the isolation effect.

[0055] As an embodiment of the present invention, the second through hole 54 and the third through hole 55 are symmetrically arranged with respect to the center of the first through hole 53, so that the second through hole 54 and the third through hole 55 can be separated by the farthest distance within the limited space of the isolation bracket 52, thereby ensuring the isolation distance between the second connecting plate 22 and the third connecting plate 61 and improving the isolation effect.

[0056] As an embodiment of the present invention, the first through hole 53 is in the shape of an elongated strip; one long side of the first through hole 53 corresponds to the second through hole 54, and the other long side of the first through hole 53 corresponds to the third through hole 55, which can increase the space between the second through hole 54 and the third through hole 55 as much as possible, so that the thickness of the second connecting plate 22 and the third connecting plate 61 that are allowed to pass through the second through hole 54 and the third through hole 55 is increased, which can effectively increase the overall allowable working current and improve the overall scope of application.

[0057] As an embodiment of the present invention, an opening 56 is provided on the short side of the first through hole 53 , which can increase the creepage distance between the second connecting plate 22 and the third connecting plate 61 .

[0058] As an embodiment of the present invention, the first end of the isolation bracket 52 is provided with a blocking portion 57 extending in a direction away from the first through hole 53, and the blocking portion 57 limits the first end from passing through the zero-sequence current transformer 51. When the isolation bracket 52 is inserted into the zero-sequence current transformer 51 to complete the assembly, the second end of the isolation bracket 52 is preferentially inserted into the zero-sequence current transformer 51. As the isolation bracket 52 is inserted, when the blocking portion 57 contacts the zero-sequence current transformer 51, since the size of the blocking portion 57 is larger than the internal size of the zero-sequence current transformer 51, the blocking portion 57 cannot pass through the zero-sequence current transformer 51, thereby realizing the positioning of the isolation bracket 52 and the zero-sequence current transformer 51 and improving the coordination between the isolation bracket 52 and the zero-sequence current transformer 51.

[0059] As an embodiment of the present invention, there are multiple blocking parts 57. As the use time increases, the blocking parts 57 will be damaged to a greater or lesser extent. The use of multiple blocking parts 57 can prevent the loss of positioning function between the isolation bracket 52 and the zero-sequence current transformer 51 when a certain blocking part 57 is damaged, thereby causing unnecessary influence on the overall isolation effect. Preferably, the multiple blocking parts 57 are evenly arranged, so that each blocking part 57 can be evenly stressed, thereby increasing the service life of the blocking part 57.

[0060] See also Figure 7-9. As an embodiment of the present invention, the second end of the isolation bracket 52 is provided with at least a first limiting portion 58, and the second connecting plate 22 and / or the third connecting plate 61 is provided with a second limiting portion 23. The first limiting portion 58 corresponds to the second limiting portion 23 one by one. Preferably, the first limiting portion 58 is a buckle, and the second limiting portion 23 is a protrusion. Through the cooperation of the buckle and the protrusion, when the isolation bracket 52 is inserted into the zero-sequence current transformer 51, the buckle is clamped on the protrusion, which can limit the isolation bracket 52 from being separated from the second connecting plate 22 or the third connecting plate 61, thereby avoiding the separation of the isolation bracket 52 and the zero-sequence current transformer 51, effectively improving the connection strength between the isolation bracket 52 and the zero-sequence current transformer 51, the second connecting plate 22, and the third connecting plate 61, and improving the overall reliability of use and working stability.

[0061] As an embodiment of the present invention, the second end is flush with or exceeds the zero-sequence current transformer 51 on one side of the zero-sequence current transformer 51 close to the first limit portion 58, ensuring that the isolation bracket 52 can pass through the interior of the zero-sequence current transformer 51, thereby ensuring that the second connecting plate 22 and the third connecting plate 61 at each position inside the zero-sequence current transformer 51 are effectively isolated by an isolation bracket 52, thereby improving the overall reliability of use and working stability.

[0062] As an embodiment of the present invention, an arc extinguishing mechanism 7 is provided at the position where the moving contact 32 and the stationary contact 34 abut against each other, which can improve the arc extinguishing effect and improve the overall safety of use. Preferably, the arc extinguishing mechanism 7 adopts an arc extinguishing chamber system.

[0063] See also Fig.10 and Fig.11 As an embodiment of the present invention, an L terminal 211, a JP3 terminal 212 and a JP4 terminal 213 are provided on the first connecting plate 21. Preferably, the JP3 terminal 212 and the JP4 terminal 213 are made of manganese copper material. The L terminal 211, the JP3 terminal 212 and the JP4 terminal 213 all extend out of the housing 1 and are connected to the PCB board of the electric energy meter. The L terminal 211 supplies power to the electric energy meter, and the JP3 terminal 212 and the JP4 terminal 213 are used for current sampling and electric energy metering of the load circuit; at the same time, the zero-sequence current transformer 51 is required to have a wider range to perform recalibration on the load circuit current and sampling of the leakage current.

[0064] Main product indicators (including main functions and performance):

[0065] 1. The dimensions are suitable for integration into smart IoT meters;

[0066] 2. Connect the load circuit when paying and disconnect the load circuit when the payment is in arrears;

[0067] 3. The current acquisition device of the integrated load circuit has the function of collecting N-phase current or load circuit leakage current in a wide range.

[0068] Technical requirements and key indicators:

[0069] (1) The load switch's rated safe short-time withstand current capability (6000A, 10ms), rated working short-time withstand current capability (3000A, 10ms), and rated short-circuit current capability (3000A, 10ms) shall meet the UC3 test requirements in Table 22 of GB / T17215.231-2021;

[0070] (2) The contact resistance of the load switch should be ≤0.5mΩ;

[0071] (3) After the load switch has been tested as follows, the closing and opening functions are normal, the switch contact resistance is ≤1.0mΩ, and the live wire in and out should withstand a 2kV withstand voltage test when the switch is disconnected; 150A, ≥8h; 200A, ≥4h;

[0072] (4) Load switch action time: disconnection ≤ 150ms, closing ≤ 200ms;

[0073] (5) The electrical gap between the moving contact and the static contact of the load switch shall not be less than 5.5mm; when the load switch is in the off position, the lead-out terminals of the main circuit of the load switch shall be able to withstand an impulse withstand voltage of 6kV;

[0074] (6) The motor drive power consumption (peak value) of the motor-type built-in switch shall not exceed 19.5W (1.3A, 15Vdc, 25ms);

[0075] (7) The mechanical life of the load switch when no-load is not less than 20,000 times; the electrical life when loaded is not less than 10,000 times (electrical life test conditions: 1.5Imax, power factor of 1.0 and 0.5L, the electrical life is not less than 5,000 times);

[0076] (8) When the load switch is passed through a current of 120A, the temperature rise of the main circuit lead-out terminal (terminal) shall not exceed 50K, and the temperature rise of the surface of the load switch housing shall not exceed 40K;

[0077] (9) The load switch is closed, 500A current is applied, and the switch is disconnected after 3s. This is performed 10 times on the same load switch, with a 3min interval between each test. The contacts of the tested sample should not stick, and the sample should be able to perform normal opening and closing operations after the test. The change rate of contact resistance before and after the test should not exceed 50%.

[0078] In summary, the present invention provides a load switch for a smart meter, which applies a driving force to the shaft bracket 31 through a cam assembly to realize and maintain the abutment between the moving contact 32 and the static contact 34, thereby improving the stability of the abutment between the two. When the load circuit is disconnected, the cam assembly releases the driving force on the shaft bracket 31, and under the action of the reset member 33, the moving contact 32 and the static contact 34 can be quickly separated, thereby reducing the generation of arcs and improving safety. The overall structure is simple and the cost is low. The connecting hole 312 and the connecting part 313 are respectively located on both sides of the shaft bracket 31, so that the force from the reset member 33 and the force from the cam assembly are The driving forces are mutually opposite forces, and the rotation direction of the rotating shaft bracket 31 is controlled by the magnitude relationship of the two forces, so as to realize the abutment or separation between the moving contact 32 and the static contact 34. The overall structure is simple and the control is simple, which improves the practicality. The multi-contact structure can effectively reduce the contact resistance between the moving contact 32 and the static contact 34, reduce the temperature rise, increase the service life of the moving contact 32 and the static contact 34, and improve the overall safety of use. When the moving contact 32 abuts against the static contact 34, the energy storage component stores a certain amount of energy. When the load circuit is disconnected, the energy stored in the energy storage component is released, which promotes The moving contact 32 is quickly separated from the stationary contact 34; the second connecting plate 22 and the third connecting plate 61 are respectively arranged in the second through hole 54 and the third through hole 55, so that the distance of the isolation gap between the second connecting plate 22 and the third connecting plate 61 can be stable, so that the overall creepage distance is stable, and the reliability and stability of the isolation effect are improved. By adding the first through hole 53, the contact between the neutral wire component and the live wire component through solid conduction can be reduced, and the reliability and stability of the isolation effect can be further improved. The overall structure is simple, the installation is convenient, and the use cost is low; the blocking part 57 cannot pass through the zero-sequence current transformer 51 to achieve isolation The isolation bracket 52 is positioned with respect to the zero-sequence current transformer 51, and the coordination between the isolation bracket 52 and the zero-sequence current transformer 51 is improved; a plurality of blocking parts 57 are evenly arranged, so that the force on each blocking part 57 is evenly applied, and the service life of the blocking part 57 is improved; the coordination of the buckle and the protrusion can limit the isolation bracket 52 from being separated from the second connecting plate 22 or the third connecting plate 61, thereby avoiding the separation of the isolation bracket 52 and the zero-sequence current transformer 51, effectively improving the connection strength between the isolation bracket 52 and the zero-sequence current transformer 51, the second connecting plate 22, and the third connecting plate 61, and improving the overall reliability of use and working stability.

[0079] It should be emphasized that the above are only preferred embodiments of the present invention and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A load switch for a smart meter, characterized in that: The invention comprises a housing (1), wherein a neutral line assembly, a live line assembly, a driving mechanism, a closing mechanism and an isolating mechanism are arranged in the housing (1), wherein the driving mechanism controls the opening and closing of the closing mechanism, and the isolating mechanism is used to isolate the neutral line assembly from the live line assembly, wherein the live line assembly comprises a first connecting plate (21) and a second connecting plate (22) which are separated, and wherein the closing mechanism comprises a first rotating shaft (30) arranged on the housing (1), a rotating shaft support (31) arranged on the first rotating shaft (30), a moving contact (32) arranged on the rotating shaft support (31), a cam assembly for driving the rotating shaft support (31) to rotate around the first rotating shaft (30), a reset member (33) for limiting the rotation of the rotating shaft support (31), and a stationary contact (34) arranged on the second connecting plate (22), wherein the moving contact (32) is electrically connected to the first connecting plate (21); When the switch is closed, the driving mechanism drives the cam assembly to rotate in a first direction, the cam assembly applies a driving force to the rotating shaft bracket (31) and drives the rotating shaft bracket (31) to rotate, the moving contact (32) moves in the direction of the stationary contact (34) and abuts against the stationary contact (34), and then the rotating shaft bracket (31) remains stationary; When the switch is opened, the driving mechanism drives the cam assembly to rotate in the second direction, the cam assembly releases the driving force on the rotating shaft bracket (31), the reset member (33) applies a pulling force to the rotating shaft bracket (31), and the moving contact (32) moves in a direction away from the stationary contact (34) to separate the moving contact (32) from the stationary contact (34).

2. The load switch for the smart meter according to claim 1, characterized in that: The driving mechanism comprises a control board (41) arranged in the housing (1), a motor (42) controlled by the control board (41), a worm (43) and a worm wheel (44) arranged at the driving end of the motor (42), and the worm wheel (44) is meshed with the cam assembly.

3. The load switch for the smart meter according to claim 2, characterized in that: The cam assembly comprises a second rotating shaft (35) arranged in the housing (1), a gear portion (36) arranged on the second rotating shaft (35), and a cam portion (37) arranged on the gear portion (36); the gear portion (36) is meshed with the worm gear (44); when the switch is closed, the cam portion (37) abuts against the rotating shaft bracket (31) and applies a driving force to the rotating shaft bracket (31).

4. The load switch for the smart meter according to claim 1, characterized in that: The rotating shaft bracket (31) comprises a main body (311) rotating around the first rotating shaft (30), and the main body (311) is provided with a connecting hole (312) and a connecting portion (313), wherein the connecting hole (312) is used to be connected to the reset member (33), and the connecting portion (313) abuts against the cam assembly and bears the driving force from the cam assembly.

5. The load switch for the smart meter according to claim 1, characterized in that: There are a plurality of movable contacts (32) and a plurality of stationary contacts (34), and the movable contacts (32) and the stationary contacts (34) are the same in number and correspond one to one.

6. The load switch for the smart meter according to claim 1, characterized in that: An energy storage component is provided between the moving contact (32) and the rotating shaft support (31).

7. The load switch for the smart meter according to claim 1, characterized in that: The isolation mechanism comprises a zero-sequence current transformer (51) arranged on the housing (1) and an isolation bracket (52) arranged in the middle of the zero-sequence current transformer (51); the zero-line assembly comprises a third connecting plate (61); the second connecting plate (22) and the third connecting plate (61) both pass through the zero-sequence current transformer (51); and the isolation bracket (52) isolates the second connecting plate (22) from the third connecting plate (61).

8. The load switch for the smart electric meter according to claim 7, characterized in that: The isolation bracket (52) is provided with a first through hole (53), and a second through hole (54) and a third through hole (55) are respectively provided on both sides of the first through hole (53); the second connecting plate (22) passes through the second through hole (54), and the third connecting plate (61) passes through the third through hole (55).

9. The load switch for the smart meter according to claim 8, characterized in that: The first end of the isolation bracket (52) is provided with a blocking portion (57) extending in a direction away from the first through hole (53), and the blocking portion (57) limits the first end from passing through the zero-sequence current transformer (51); the second end of the isolation bracket (52) is provided with at least a first limiting portion (58), and the second connecting plate (22) and / or the third connecting plate (61) are provided with a second limiting portion (23), and the first limiting portion (58) corresponds to the second limiting portion (23) one by one.

10. The load switch for the smart meter according to claim 1, characterized in that: An arc extinguishing mechanism (7) is provided at the position where the moving contact (32) abuts against the stationary contact (34).

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