A blade shutter

Abstract

The application discloses a knife switch. The knife switch comprises a moving contact and a static contact, and further comprises a sub-contact, wherein the sub-contact comprises a sub-moving contact connected with the moving contact and a sub-static contact connected with the static contact; the moving contact or the static contact is provided with a limiting constant force device to make the moving contact and the static contact rigidly contact; and the sub-moving contact or the sub-static contact is provided with an elastic mechanism to make the sub-moving contact and the sub-static contact flexibly contact. The knife switch guarantees that the moving contact and the static contact can reach the designed contact amount within a certain contact deformation amount or a matching contact position deviation, and fully guarantees the normal work between the moving contact and the static contact; the sub-contact guarantees that the knife switch static contact and the moving contact still have substantial circuit connection when the knife switch moving contact and the static contact are operated to be closed and opened, eliminates the potential difference, and prevents the potential difference from forming a breakdown arc and ablation of the contact position when the closing and opening operation is performed.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of electricity, and in particular, relates to a knife switch. BACKGROUND

[0002] The knife switch is the most widely used electrical appliance in high-voltage switchgear, and its working principle and structure are relatively simple. However, due to its large quantity of use and high reliability requirement, it has a great influence on the design, establishment and safe operation of the substation and power plant.

[0003] The main feature of the knife switch is the lack of arc extinguishing capability, and it can only be used to open and close the circuit without load current. Its main role is to establish a reliable insulation gap after opening, to separate the equipment or line to be maintained from the power supply by a clear disconnection point, to ensure the safety of the maintenance personnel and equipment; to change the line according to the operation needs; to be used to open and close small current in the line, such as the charging current of the bushing, busbar, connector and short cable, the capacitance current of the switch grading capacitor, the loop current during the double busbar switching, and the excitation current of the voltage transformer; and to be used to open and close the no-load excitation current of a certain capacity transformer according to the specific circumstances of different structural types.

[0004] Due to the deviation between the combined position of the moving and static contacts during the opening and closing of the knife switch and the design value, and the further increase of the deviation amount in use due to the wear of the moving parts and the deformation of the structural parts, the contact position of the moving and static contacts of the knife switch deviates, and even cannot be completely closed, resulting in the increase of the conductive resistance between the moving and static contacts, the increase of the working temperature, the influence on the normal work of the knife switch, and the existence of a certain voltage difference between the static and moving contacts of the knife switch due to external factors during the opening and closing of the knife switch. The air gap between the contacts is easily broken down by the voltage difference when the static and moving contacts of the knife switch are about to contact or have just separated, forming arc between the contacts, causing local high-temperature ablation damage at the contact position, increasing the resistance, and reducing the conductive capacity. The conductive capacity is reduced during the closing of the knife switch, the temperature at the contact of the knife switch is relatively high, the normal and safe transmission of power is affected, unsafe points are formed, and the reliability and working performance of the equipment are reduced.

[0005] When the knife switch is in the open state, the combined surface of the moving and static contacts of the knife switch is exposed to the air, and flying dust and other impurities are easily attached to cause poor contact between the moving and static contacts during the closing of the knife switch. In addition, due to external factors, a certain voltage difference exists between the static and moving contacts of the knife switch during the opening and closing of the knife switch. The air gap between the contacts is easily broken down by the voltage difference when the static and moving contacts of the knife switch are about to contact or have just separated, forming arc between the contacts, causing local high-temperature ablation damage at the contact position, increasing the resistance, and reducing the conductive capacity. The conductive capacity is reduced during the closing of the knife switch, the temperature at the contact of the knife switch is relatively high, the normal and safe transmission of power is affected, unsafe points are formed, and the reliability and working performance of the equipment are reduced.

[0006] The present application is proposed in view of the above. SUMMARY

[0007] The technical problem solved by the present application is to overcome the deficiencies of the prior art, and provide a knife switch.

[0008] To solve the above technical problems, the basic idea of the technical solution of the present application is:

[0009] A knife switch comprises a moving contact and a static contact, and further comprises a secondary contact, the secondary contact comprising a secondary moving contact connected to the moving contact and a secondary static contact connected to the static contact, the moving contact or the static contact is provided with a limiting constant force device to make the moving contact and the static contact rigidly contact, and the secondary moving contact or the secondary static contact is provided with an elastic mechanism to make the secondary moving contact and the secondary static contact flexibly contact.

[0010] The moving contact comprises a cylindrical structure and a conductive rod, the conductive rod drives the cylindrical structure and the secondary moving contact to move, a limiting constant force device is arranged between the cylindrical structure and the conductive rod, and an elastic mechanism is arranged between the secondary moving contact and the conductive rod.

[0011] The limiting constant force device comprises a housing and a force bearing column, the force acting between the housing and the force bearing column along the circumference of the force bearing column is constant and can produce relative displacement, the housing is fixedly connected to the conductive rod, and the force bearing column is fixedly connected to the cylindrical structure of the moving contact.

[0012] Preferably, a spring set is arranged between the housing and the force bearing column, the spring set keeps the resultant force of the housing / force bearing column along the axial direction of the force bearing column constant, and the spring set comprises a main spring and an auxiliary spring.

[0013] More preferably, one end of the main spring is fixed to a main spring fixed side base plate fixedly connected to the housing, and the other end is fixed to a moving side base plate fixedly connected to the force bearing column.

[0014] More preferably, the auxiliary spring comprises at least a first auxiliary spring and a second auxiliary spring, the circumference of the force bearing column comprises at least a first roller corresponding to the first auxiliary spring and a second roller corresponding to the second auxiliary spring, a first swing arm is arranged between the first roller and the first auxiliary spring, a second swing arm is arranged between the second roller and the second auxiliary spring, and one end of the first swing arm / second swing arm can rotate along a fulcrum fixed to the housing.

[0015] Further preferably, the first roller / second roller is rotatably arranged in the circumference of the main spring moving side base plate and can move along the radial direction of the force bearing column to exert force on the first swing arm / second swing arm.

[0016] The knife switch is a rotary knife switch, the conductive rod is rotatable along a rotation axis, the stationary contact has a groove matched with the rotation direction of the conductive rod, the force bearing column is fixedly connected with the cylindrical structure of the movable contact, the shell is fixedly connected with the conductive rod at a certain angle, the auxiliary movable contact is rotatably connected to the conductive rod through an auxiliary movable contact conductive rod, and an elastic mechanism is arranged between the auxiliary movable contact conductive rod and the conductive rod and can be deformed along the rotation direction.

[0017] The auxiliary movable contact is rotatably connected to the conductive rod through an auxiliary movable contact conductive rod and is arranged at a certain angle, and a spring is arranged between the auxiliary movable contact conductive rod and the conductive rod.

[0018] Preferably, a limiting structure is arranged on the conductive rod to limit the rotation angle of the auxiliary movable contact conductive rod.

[0019] The knife switch comprises at least a first auxiliary movable contact and a second auxiliary movable contact, the auxiliary movable contact conductive rod is bifurcated and connected to the first auxiliary movable contact and the second auxiliary movable contact respectively, and the first auxiliary movable contact and the second auxiliary movable contact can respectively touch different auxiliary stationary contacts; preferably, springs are arranged on both sides of the auxiliary movable contact conductive rod.

[0020] The knife switch is a telescopic knife switch, the conductive rod is telescopic, the stationary contact has a groove matched with the telescopic direction of the conductive rod, the conductive rod comprises coaxially nested first and second conductive rods, the first conductive rod is fixedly connected with the shell, the second conductive rod is fixedly connected with the force bearing column, the auxiliary movable contact is fixedly connected to the conductive rod through an auxiliary movable contact conductive rod, and the auxiliary movable contact conductive rod is provided with an elastic mechanism and can be deformed along the telescopic direction.

[0021] The auxiliary movable contact is fixedly connected to the conductive rod through an auxiliary movable contact conductive rod, the auxiliary movable contact conductive rod comprises a first section and a second section, and a spring is arranged between the first section and the second section.

[0022] The movable contact or the stationary contact is provided with a cleaning device; preferably, the movable contact is provided with a first cleaning device, the stationary contact is provided with a second cleaning device, the first cleaning device is connected with an auxiliary movable contact, and the second cleaning device is connected with an auxiliary stationary contact.

[0023] The cleaning device comprises a cleaning sheet and a moving mechanism; preferably, the movable contact has a cylindrical structure, the first cleaning device is arranged on the surface of the cylindrical structure, the moving mechanism of the first cleaning device comprises a rotating sleeve with a partial cylindrical shape, the rotating sleeve rotates along a rotating sleeve shaft passing through the center of the cylinder, and the cleaning sheet is arranged on the side of the rotating sleeve facing the cylindrical structure; preferably, the fixed contact comprises at least a first fixed contact plate and a second fixed contact plate, the movable contact is arranged between the first fixed contact plate and the second fixed contact plate and is in contact with the first fixed contact plate and the second fixed contact plate respectively, the first fixed contact plate and the second fixed contact plate are respectively sleeved with a second cleaning device, and the second cleaning device can slide along the fixed contact plate.

[0024] More preferably, the rotating sleeve is provided with a secondary movable contact, the sliding sleeve is provided with a secondary fixed contact, and after the secondary movable contact abuts against the secondary fixed contact, the rotating sleeve rotates in a direction away from the fixed contact, and the sliding sleeve slides in a direction away from the movable contact.

[0025] Compared with the prior art, the technical scheme has the following beneficial effects.

[0026] (1) The knife switch of the present application ensures that the movable contact and the fixed contact can reach the designed contact amount and contact torque size within a certain contact position deviation, thereby fully ensuring the normal operation between the movable contact and the fixed contact.

[0027] (2) The secondary contact head contacts before the movable contact and the fixed contact contact a certain distance, and the primary contact head is disconnected after the secondary contact head is disconnected a certain distance, thereby ensuring that the movable contact and the fixed contact of the knife switch still have substantial circuit connection when the knife switch is closed and disconnected, and there is no potential difference between the movable contact and the fixed contact, so that no breakdown arc is formed when the knife switch is closed and disconnected, and the contact position is not ablated.

[0028] (3) The movable contact and the fixed contact of the knife switch are provided with a cleaning device, and the rotating sleeve or the sliding sleeve is internally provided with a cleaning sheet, so that the contact surface of the knife switch is automatically cleaned during the disconnection and closure of the knife switch, thereby ensuring the cleanliness of the contact surface.

[0029] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0030] The accompanying drawings, which are part of the present application, serve to provide a further understanding of the present application, and the illustrative embodiments of the present application and their descriptions serve to explain the present application but do not constitute an improper limitation on the present application. Obviously, the accompanying drawings in the following description are only some embodiments, and other drawings can be obtained by those skilled in the art without creative labor. In the drawings:

[0031] Figure 1 is a schematic diagram of a rotary knife switch;

[0032] Figure 2 is a schematic diagram of a telescopic knife switch;

[0033] Figure 3 is a schematic diagram of a limiting constant force device;

[0034] Figures 4-6 is a schematic diagram of a limiting constant force device provided for a moving contact of a rotary knife switch of the present application;

[0035] Figure 7 is a schematic diagram of a limiting constant force device provided for a stationary contact of a rotary knife switch of the present application;

[0036] Figures 8-11 is a schematic diagram of a secondary contact provided for a rotary knife switch of the present application;

[0037] Figures 12-13 is a schematic diagram of a limiting constant force device provided for a moving contact of a telescopic knife switch of the present application;

[0038] Figure 14 is a schematic diagram of a limiting constant force device provided for a stationary contact of a telescopic knife switch of the present application;

[0039] Figures 15-16 is a schematic diagram of a secondary contact provided for a telescopic knife switch of the present application;

[0040] Figure 17 is a schematic diagram of a moving contact provided with a first cleaning device of the present application;

[0041] Figure 18 is a schematic diagram of a stationary contact provided with a second cleaning device of the present application.

[0042] In the figure: 1, moving contact; 11, cylindrical structure; 12, conductive rod; 121, first conductive rod; 122, second conductive rod; 13, rotating shaft; 14, fulcrum; 2, stationary contact; 21, stationary contact part; 22, stationary contact base;

[0043] 3, secondary moving contact; 31, secondary moving contact conductive rod; 311, first section; 312, second section; 313, conductive piston; 32, first secondary moving contact; 33, second secondary moving contact; 34, spring; 4, secondary stationary contact; 41, secondary stationary contact conductive rod;

[0044] 5, limiting constant force device; 51, housing; 511, main spring fixed side base plate; 512, adjusting bolt; 52, force bearing column; 521, main spring moving side base plate; 522, roller; 523, rotating shaft; 531, main spring; 532, auxiliary spring; 54, swing arm;

[0045] 611, rotating sleeve; 612, first cleaning piece; 613, first homing device; 614, rotating sleeve shaft; 621, sliding sleeve; 622, second cleaning piece; 623, second homing device.

[0046] It should be noted that the drawings and the written description are not intended to limit the scope of the present application in any way, but are merely to illustrate the concept of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments will be described clearly and completely below with reference to the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application, but are not used to limit the scope of the present application.

[0048] In the description of the present application, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are merely for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0049] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0050] As Figures 1-18 shown, the present application relates to a knife switch, which is improved according to the commonly used form and structure of the knife switch. On the basis of retaining the original structure of the knife switch, the improvement can be made according to the actual situation on site.

[0051] As Figure 1 and Figure 2 described, the knife switch generally includes a moving contact 1 and a stationary contact 2. The stationary contact is arranged at a fixed position, and the moving contact can move. When the moving contact and the stationary contact are in contact, the knife switch is in a closed state, which can make the circuit continuous. When the moving contact moves and has a certain distance from the stationary contact, the knife switch is in an open state, and the circuit connected therewith is also disconnected.

[0052] According to different moving modes of the moving contact, the knife switch can be divided into a rotary knife switch and a telescopic knife switch, Figure 1This is a schematic diagram of a rotary disconnect switch. The moving contact has a cylindrical structure 11 and a conductive rod 12. The conductive rod can rotate along a rotating shaft 13. The stationary contact has a groove that matches the cylindrical structure of the moving contact, allowing the cylindrical structure of the moving contact to fit into it. The conductive rod is not along the diameter direction of the cylindrical structure, but rather at a certain angle to the diameter direction. Because the conductive rod rotates along the rotating shaft, the opening of the groove in the stationary contact faces the direction of the arc path of the moving contact.

[0053] like Figure 2 As shown, Figure 2 The diagram shows a telescopic knife switch. The moving contact has a cylindrical structure 11 and a conductive rod 12. The conductive rod is telescopic, with one end fixed to the fulcrum 14 and extending and retracting along the direction of the conductive rod 12. The stationary contact 2 has a groove facing the moving contact 1, into which the cylindrical structure 11 can be inserted.

[0054] The present invention adds a limiting constant force device 5 at a suitable position on the moving or stationary contact of the knife switch, so that the stationary or moving contact of the knife switch can still have a certain compressive force when stopped, even when it has a certain deformation, thus ensuring the normal operation of the knife switch.

[0055] The limiting constant force device is as follows Figure 3 As shown, the structure includes a housing 51, a support column 52, and a spring assembly. The spring assembly includes a main spring 531 and an auxiliary spring 532. The main spring 531 applies a force F1 to the support column / housing, and the auxiliary spring 532 applies a force F2 to the support column / housing. The resultant force of F1 and F2 in the axial direction of the support column is constant.

[0056] The specific structure further includes that one end of the main spring is fixed to the main spring fixed side base plate 511, and the other end is fixed to the main spring moving side base plate 521. The main spring fixed side base plate 511 is fixedly connected to the housing 51, and the main spring moving side base plate 521 moves synchronously with the load-bearing column 52. An adjusting bolt 512 is also provided between the main spring fixed side base plate 511 and the housing. The adjusting bolt can adjust the position of the main spring moving side base plate 511, thereby adjusting the compression of the main spring, so as to adjust the magnitude of the external force exerted by the load-bearing column / housing. A limiting hole is provided on the main spring fixed side base plate for the movement of the load-bearing column.

[0057] The auxiliary spring 532 at least includes a first auxiliary spring and a second auxiliary spring, and the auxiliary spring is arranged in the circumference of the force bearing column; in order to ensure uniform distribution of force in the circumference, the auxiliary spring can also be arranged in the circumference in multiple; the auxiliary spring 532 is arranged with a swing arm 54 between the force bearing column; the swing arm has an arc structure, and can also be arranged in a special-shaped structure according to different requirements. One end of the swing arm is fixed on the shell, and the swing arm can rotate along the rotating shaft 523; the roller 522 is arranged on the force bearing column, and the roller 522 can move on the arc surface of the swing arm 54. The other side of the swing arm is fixedly connected with the auxiliary spring 532; when the roller moves on the force bearing column, the roller moves on the arc surface of the swing arm, so that the swing arm rotates along the rotating shaft, thereby making the auxiliary spring have different deformation amounts and generate different acting forces.

[0058] The circumference of the force bearing column at least includes a first roller corresponding to the first auxiliary spring and a second roller corresponding to the second auxiliary spring; the first roller is arranged with a first swing arm between the first auxiliary spring; the second roller is arranged with a second swing arm between the second auxiliary spring; one end of the first swing arm / second swing arm can rotate along the rotating shaft fixed on the shell; the first roller / second roller is rotatably arranged in the circumference of the main spring movement side base plate, and can exert an acting force on the first swing arm / second swing arm along with the main spring movement side base plate moving radially on the force bearing column.

[0059] The above device adopts the torque balance principle; the main spring and the auxiliary spring are used to cooperate with the main spring movement side base plate and the auxiliary spring swing arm, to give the main spring a downward stretching force when the compression amount of the main spring is small, and to give the main spring an upward compression force when the compression amount of the main spring is large, so as to ensure that the force bearing column connected with the main spring always maintains stability within a certain displacement amount to the external torque; an adjusting bolt is arranged on the upper portion, and the deformation amount of the limiting constant force device can be adjusted according to the actual situation on site or the deformation amount of the workpiece during each maintenance work. After the dynamic contact or the static contact is installed with the limiting constant force module, the dynamic contact and the static contact can reach the designed contact amount and the contact torque size within a certain contact deformation amount or a contact position deviation, so as to fully ensure the normal work between the dynamic contact and the static contact.

[0060] The knife switch of the application is provided with a secondary contact, which includes a secondary dynamic contact 3 and a secondary static contact 4. The secondary contact is used to make contact before the dynamic contact and the static contact make contact. The secondary contact makes contact before the dynamic contact and the static contact are closed by an elastic mechanism, and is disconnected after the dynamic contact and the static contact are disconnected for a certain time. The secondary contact ensures that the main dynamic contact and the main static contact of the knife switch are still connected in a substantial circuit when the main dynamic contact and the main static contact are closed and disconnected, eliminates the potential difference, and avoids the potential difference formed by the existing knife switch when the main dynamic contact and the main static contact are closed and disconnected, so as to avoid the arc breakdown and the ablation of the contact position, and to ensure the normal and safe transmission of power.

[0061] The auxiliary moving contact is connected with the conductive rod 12 through the auxiliary moving contact conductive rod 31, and the auxiliary stationary contact is connected with the stationary contact 2 through the auxiliary stationary contact conductive rod 41.

[0062] The moving contact and the stationary contact are in hard contact through the limiting constant force device, and the auxiliary moving contact and the auxiliary stationary contact are in flexible contact through the elastic mechanism.

[0063] The limiting constant force device is arranged on the moving contact or the stationary contact, and the elastic mechanism is arranged on the auxiliary contact, so that various embodiments are obtained according to different types of knife switches and different setting positions.

[0064] Embodiment one

[0065] As shown in Figure 4 , the limiting constant force device is arranged at the position of the moving contact of the rotary knife switch.

[0066] The moving contact comprises a cylindrical structure 11 and a conductive rod 12, and the cylindrical structure and the conductive rod in the prior art are arranged integrally or fixedly connected, and in the embodiment, the limiting constant force device is arranged between the cylindrical structure and the conductive rod.

[0067] The conductive rod is fixedly connected with the shell at a certain angle, the cylindrical structure is fixedly connected with the force bearing column, and the force bearing column is arranged along the radial direction of the cylindrical structure, as shown in the figure; or the conductive rod is fixedly connected with the force bearing column, and the cylindrical structure is fixedly connected with the shell, which is not shown in the figure.

[0068] As shown in Figure 5 and Figure 6 , due to the setting of the groove of the stationary contact, the cylindrical structure 11 and the conductive rod 12 of the moving contact are connected at an angle, and the angle should be able to ensure that the moving contact and the stationary contact can be in close contact. In order to ensure the direction of the force applied by the force bearing column to the cylindrical structure, the force bearing column is arranged along the direction of one diameter of the cylindrical structure.

[0069] The setting mode of the auxiliary contact can be as shown in Figure 8 or Figure 10 .

[0070] Figure 9 is Figure 8 an enlarged schematic view of A in Figure 9As shown, the auxiliary moving contact conductive rod 31 is rotatably connected to the conductive rod 12. The elastic mechanism includes a spring 34 disposed between the auxiliary moving contact conductive rod 31 and the conductive rod 12. The auxiliary moving contact conductive rod 31 and the conductive rod 12 are partially limited by the spring 34 to ensure that the auxiliary moving contact 3 always tends to move towards the auxiliary stationary contact 4. A limit structure 35 is also provided on the conductive rod 12 to limit the rotation range of the auxiliary moving contact conductive rod and prevent uncontrollable rotation of the auxiliary moving contact conductive rod under extreme working conditions or in the event of spring 34 failure.

[0071] When the knife switch is disconnected, due to the action of spring 34, the auxiliary contact will disconnect after the moving contact and the stationary contact have been separated by a certain distance. The auxiliary contact will make contact a certain distance before the moving contact and the stationary contact make contact, ensuring that the auxiliary contact is already connected when the moving contact and the stationary contact are closed and opened, ensuring that the circuit is unobstructed, there is no potential difference between the moving contact and the stationary contact, and no breakdown arcing or burning of the contact position will occur.

[0072] Considering the working environment of the disconnector in switching circuits, two auxiliary moving contacts are set on the auxiliary contact conductive rod to realize the feasibility and versatility of the switching operation settings.

[0073] Specifically, such as Figure 10 and Figure 11 As shown, Figure 11 for Figure 10 The enlarged view at point B shows that the auxiliary contact includes a first auxiliary contact 32 and a second auxiliary contact 33. The first auxiliary contact 32 and the second auxiliary contact 33 are connected to the auxiliary contact conductive rod 31 at a certain angle through a conductive rod. The first auxiliary contact 32 and the second auxiliary contact 33 are separated by a certain angle to realize the feasibility and diversity of switching working settings.

[0074] like Figure 11 As shown, a limiting plate is provided on the conductive rod 12 and is perpendicularly connected to it. The elastic mechanism includes springs 34 disposed between the limiting plate and the auxiliary contact conductive rod 31 and between the conductive rod 12 and the auxiliary contact conductive rod 31. Two springs in opposite directions are disposed between the auxiliary contact conductive rod 31 and the conductive rod 12 to achieve bidirectional tendency when the first auxiliary contact 32 and the second auxiliary contact 33 make contact in two directions. When contacting the stationary contacts of two different circuits, they can close before the main contact and open after the main contact, which can fully protect the main contact.

[0075] Example 2

[0076] like Figure 7 As shown, the rotary knife switch is equipped with a limit constant force device at the stationary contact position.

[0077] The stationary contact includes a stationary contact portion 21 and a stationary contact base 22, with a limiting constant force device provided between the stationary contact portion 21 and the stationary contact base 22. The stationary contact portion is fixedly connected to a load-bearing column, and the stationary contact base is fixedly connected to a housing, as shown in the figure; alternatively, the stationary contact portion is fixedly connected to the housing, and the stationary contact base is fixedly connected to a load-bearing column, but not shown in the figure.

[0078] Preferably, the stationary contact includes a first stationary contact and a second stationary contact. Since the moving contact 1 has a cylindrical structure, the force applied to the stationary contact is directed in different directions. Therefore, at least two stationary contacts are provided to cope with the forces applied to the moving contact in different directions. Limiting constant force devices are provided between the first stationary contact and the stationary contact base, and between the second stationary contact and the stationary contact base.

[0079] The cylindrical structure of the moving contact can be fixedly connected to the conductive rod or integrated into one piece.

[0080] The secondary contact configuration in this embodiment is the same as in the previous embodiment.

[0081] Example 3

[0082] like Figure 12 As shown, the telescopic knife switch is equipped with a limit constant force device at the moving contact position.

[0083] The moving contact includes a first conductive rod 121, a second conductive rod 122, and a cylindrical structure 11. The first conductive rod 121 and the cylindrical structure 11 are fixedly connected. The limiting constant force device 5 is disposed between the first conductive rod 121 and the second conductive rod 122. Since the knife switch in this embodiment is a telescopic knife switch, the diameter of the cylindrical structure and the first conductive rod are on the same straight line.

[0084] like Figure 13 As shown in the figure, the first conductive rod 121 is fixedly connected to the housing 51, and the second conductive rod 122 is fixedly connected to the support column 52; or, the first conductive rod is fixedly connected to the support column, and the second conductive rod is fixedly connected to the housing, not shown in the figure. The first conductive rod and the second conductive rod are coaxially nested and can move relative to each other along the axial direction.

[0085] Since the disconnect switch is a telescopic disconnect switch, the conductive rod 12 includes a telescopic section. In the above arrangement, the first conductive rod and the second conductive rod are positioned close to the cylindrical structure to ensure that the telescopic section does not affect the limiting constant force device. The first conductive rod and the second conductive rod can have a certain relative displacement along the axial direction, but the force between the cylindrical structure of the moving contact and the groove of the stationary contact remains unchanged under the action of the limiting constant force device.

[0086] The arrangement of the secondary contact elastic mechanism is as follows: Figure 15 and Figure 16As shown, Figure 16 To Figure 15 Enlarged view at C.

[0087] The telescopic section of the conductive rod 12 is connected with a sub-moving contact conductive rod 31, which is hard connected with the telescopic section of the conductive rod, that is, the sub-moving contact conductive rod 31 is telescopic with the telescopic section of the conductive rod 12, and one end of the sub-moving contact conductive rod is fixedly connected with the telescopic section of the conductive rod 12.

[0088] The sub-moving contact conductive rod 4 comprises a first section 311 and a second section 312, the first section comprises a horizontal section and a vertical section which are integrally connected in an L shape, the end of the horizontal section is connected with the conductive rod 12, and the upper end of the vertical section and the lower end of the second section 312 are connected through the elastic mechanism.

[0089] The first section 311 and the second section 312 are internally hollow conductive rods, the elastic mechanism comprises a conductive piston 313 which is slidably connected in the first section 311 and the second section 312, the diameter of the conductive piston 313 is smaller than that of the sub-moving contact conductive rod 31, the conductive piston 313 is limitedly connected in the sub-moving contact conductive rod 31, specifically, the end of the first section 311 and the second section 312 is provided with a limiting surface, a through hole is formed in the center of the limiting surface, the diameter of the through hole matches the diameter of the conductive piston 313, the conductive piston 313 can enter into the first section 311 and the second section 312 through the through hole, and limiting portions are arranged at both ends of the conductive piston 313, the conductive piston 313 is limited in the first section 311 and the second section 312 by the limiting portions, in the embodiment, the diameter of the limiting portions is smaller than that of the sub-moving contact conductive rod 31 and larger than that of the through hole, the conductive piston 313 is slidably limited in the first section 311 and the second section 312, that is, the conductive piston 313 cannot leave the sub-moving contact conductive rod 31, so as to ensure the normal connection of the circuit.

[0090] The elastic mechanism further comprises a spring 34, the spring 34 is sleeved on the conductive piston 313 and connected at both ends with the first section and the second section. By arranging the conductive piston and the spring, the sub-contact is always in the maximum length trend, the sub-moving contact conductive rod 31 is elongated as much as possible, after the sub-contact is contacted, the spring is compressed under force, the sub-moving contact conductive rod is shortened by the movement of the conductive piston, so as to ensure that the sub-contact is contacted before the moving contact and the static contact are contacted, within a certain distance after the moving contact and the static contact are disconnected, the sub-contact is always kept in the contact state under the action of the spring, so as to ensure that there is no voltage difference between the moving contact and the static contact, and prevent the damage of the contact surface caused by the breakdown and arc.

[0091] Embodiment four

[0092] As Figure 14As shown, the telescopic knife switch is provided with a limiting constant force device at the position of the static contact.

[0093] The static contact comprises a static contact part 21 and a static contact base 22, and a limiting constant force device is arranged between the static contact part 21 and the static contact base 22. The static contact part is fixedly connected with a force bearing column, and the static contact base is fixedly connected with a shell, as shown in the figure, or the static contact part is fixedly connected with a static contact shell, and the base is fixedly connected with a force bearing column, which is not shown in the figure.

[0094] Preferably, the static contact part comprises a first static contact part and a second static contact part. Since the moving contact 1 has a cylindrical structure, the force acting on the static contact is directed in different directions, and at least two static contact parts are arranged to cope with the different directions of the force exerted by the moving contact. A limiting constant force device is arranged between the first static contact part and the static contact base and between the second static contact part and the static contact base. The cylindrical structure of the moving contact and the conductive rod can be fixedly connected or integrally arranged.

[0095] The sub-contact in the embodiment is arranged in the same way as in the previous embodiment.

[0096] The knife switch of the application is also provided with a cleaning device arranged on the moving contact and / or the static contact, which comprises a cleaning sheet and a moving mechanism, and the moving mechanism drives the cleaning sheet to move on the surface of the moving contact and / or the static contact.

[0097] As shown in the figures, Figure 17 and Figure 18 The moving contact is provided with a first cleaning device, and the static contact is provided with a second cleaning device. The cleaning device can be arranged on a rotary knife switch or a telescopic knife switch.

[0098] The first cleaning device is arranged on the surface of the cylindrical structure 11, the moving mechanism of the first cleaning device comprises a rotating sleeve 611 with a partial cylindrical shape, the rotating sleeve rotates along a rotating sleeve shaft 614 passing through the center of the cylinder, the moving contact is provided with a first cleaning sheet 612 arranged on the side of the rotating sleeve facing the cylindrical structure. One end of the rotating sleeve is connected with a first homing device 613, which can be a spring, and after the rotating sleeve moves, the first homing device can drive the rotating sleeve to return to the initial position.

[0099] The static contact comprises at least a first static contact plate and a second static contact plate, the moving contact is arranged between the first static contact plate and the second static contact plate and respectively contacts the first static contact plate and the second static contact plate, and a second cleaning device is arranged on the first static contact plate and the second static contact plate respectively, and the second cleaning device can slide along the static contact plate.

[0100] The moving mechanism of the second cleaning device comprises a sliding sleeve 621 sleeved on the static contact plate, and a second cleaning sheet 622 is arranged on the inner wall of the sliding sleeve 621 and faces the contact surface of the static contact plate. The sliding sleeve is connected with a second homing device 623 at one end, and the second homing device can be a spring and can drive the sliding sleeve to return to the initial position.

[0101] The rotating sleeve is provided with a secondary moving contact 3, and the sliding sleeve is provided with a secondary static contact 4. After the secondary moving contact 3 abuts against the secondary static contact 4, the rotating sleeve 611 rotates away from the static contact, and the sliding sleeve 621 slides away from the moving contact. The secondary moving contact and the rotating sleeve have an elastic mechanism, and the secondary static contact is elastically connected with the sliding sleeve. The secondary contact will be disconnected after the moving contact and the static contact are disconnected by a certain distance, and the secondary contact will be connected before the moving contact and the static contact are connected by a certain distance, so that the main contact is connected when the main contact is closed and disconnected, the circuit is smooth, and there is no potential difference between the main contact and the static contact.

[0102] The arrangement position of the secondary contact can be adjusted according to the actual situation of the production site, and spatial dislocation arrangement can be realized. Since the secondary contact is only used to realize that the potential of the main contact is equal to that of the moving contact before the main contact is contacted, the position of the secondary contact moving contact and the static contact can be made of cheap materials resistant to high temperature and ablation.

[0103] The knife switch of the application can ensure that the moving contact and the static contact can reach the designed contact amount and contact torque size within a certain contact deformation amount or matching contact position deviation, and fully ensure the normal work between the moving contact and the static contact. The secondary contact is contacted before the moving contact and the static contact are contacted by a certain distance, the pre-contact head or the secondary contact is disconnected after the main contact is disconnected by a certain distance, the static contact and the moving contact of the main contact are still substantially connected in circuit when the main contact is closed and disconnected, there is no potential difference between the static contact and the moving contact, and there is no potential difference to form a breakdown arc when the main contact is closed and disconnected, and the contact position is ablated. The moving contact and the static contact of the knife switch are provided with a cleaning device, and a cleaning sheet is arranged in the rotating sleeve or the sliding sleeve. The contact surface of the knife switch is automatically cleaned during the disconnection and closing process of the knife switch, so that the contact surface is clean.

[0104] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed with the preferred embodiments as above, it is not intended to limit the present application, and any person skilled in the art can make some changes or modifications to the above-mentioned technical content with the prompt as equivalent embodiments of equivalent changes without departing from the technical solution of the present application. Any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application, which does not depart from the technical solution of the present application, still belongs to the scope of the present application.

Claims

1. A blade shutter, characterized in that, Comprise: The moving contact and the static contact, the moving contact has a cylindrical structure and a conductive rod, the conductive rod can rotate along the rotating shaft, the static contact has a groove matched with the cylindrical structure of the moving contact for the cylindrical structure of the moving contact to fall into, the groove opening of the static contact faces the direction of the circular arc path of the moving contact; Also including the auxiliary contact, the auxiliary contact includes the auxiliary moving contact and the auxiliary static contact, the auxiliary moving contact is connected with the conductive rod through the auxiliary moving contact conductive rod, the auxiliary static contact is connected with the static contact through the auxiliary static contact conductive rod; The moving contact is provided with a limiting constant force device to make the moving contact and the static contact rigidly contact, the auxiliary moving contact is provided with an elastic mechanism to make the auxiliary moving contact and the auxiliary static contact flexibly contact; The limiting constant force device includes a shell, a force bearing column, a main spring and an auxiliary spring; One end of the main spring is fixed on the main spring fixed side base plate, the other end is fixed on the main spring moving side base plate, the main spring fixed side base plate is fixedly connected with the shell, the main spring fixed side base plate is provided with a limiting hole for the movement of the force bearing column;The main spring moving side base plate moves synchronously with the force bearing column; The auxiliary spring includes a first auxiliary spring and a second auxiliary spring, the auxiliary spring is arranged in the circumferential direction of the force bearing column, the auxiliary spring and the force bearing column are provided with a swing arm, the swing arm has an arc structure;One end of the swing arm is fixed on the shell, the swing arm can rotate along the rotating shaft, a roller is arranged on the force bearing column, the roller can move on the arc surface of the swing arm; The main spring exerts a force F1 on the force bearing column, the auxiliary spring exerts a force F2 on the force bearing column, the resultant force of F1 and F2 in the axial direction of the force bearing column is constant; A limiting constant force device is arranged between the cylindrical structure and the conductive rod, the conductive rod is fixedly connected with the shell at a certain angle, the cylindrical structure is fixedly connected with the force bearing column, and the force bearing column is arranged along the radial direction of the cylindrical structure; The auxiliary moving contact conductive rod is rotatably connected with the conductive rod; The auxiliary moving contact includes a first auxiliary moving contact and a second auxiliary moving contact connected with the auxiliary moving contact conductive rod for contacting the static contacts of two different lines, the first auxiliary moving contact and the second auxiliary moving contact are separated by a certain angle; A limiting plate is arranged on the conductive rod and connected perpendicularly therewith, the elastic mechanism includes two springs arranged between the limiting plate and the auxiliary moving contact conductive rod and between the conductive rod and the auxiliary moving contact conductive rod respectively.

2. The knife switch according to claim 1, wherein The force bearing column circumferentially includes at least a first roller corresponding to the first auxiliary spring and a second roller corresponding to the second auxiliary spring, a first swing arm is arranged between the first roller and the first auxiliary spring, a second swing arm is arranged between the second roller and the second auxiliary spring, and one end of the first swing arm / second swing arm can rotate along a fulcrum fixed on the shell.

3. The knife switch according to claim 2, wherein The first roller / second roller is rotatably arranged in the circumferential direction of the main spring moving side base plate and can exert a force on the first swing arm / second swing arm when the main spring moving side base plate moves along the radial direction of the force bearing column.

4. The blade shutter according to claim 1, wherein The auxiliary moving contact is arranged at a certain angle with the conductive rod through the auxiliary moving contact conductive rod.

5. The knife switch according to claim 4, wherein A limiting structure is arranged on the conductive rod to limit the rotation angle of the auxiliary moving contact conductive rod.

6. The blade shutter according to claim 1, wherein The moving contact and the stationary contact are provided with cleaning devices; The moving contact is provided with a first cleaning device, and the stationary contact is provided with a second cleaning device.

7. The blade shutter according to claim 6, characterized in that The cleaning device comprises a cleaning sheet and a moving mechanism.

8. The knife switch according to claim 7, characterized in that The first cleaning device is arranged on the surface of the cylindrical structure, and the moving mechanism of the first cleaning device comprises a rotating sleeve with a partial cylindrical shape, which rotates along a rotating sleeve shaft passing through the center of the cylinder, and the cleaning sheet is arranged on the side of the rotating sleeve facing the cylindrical structure. The stationary contact comprises at least a first stationary contact plate and a second stationary contact plate, the moving contact is trapped between the first stationary contact plate and the second stationary contact plate and is in contact with the first stationary contact plate and the second stationary contact plate respectively, the first stationary contact plate and the second stationary contact plate are respectively sleeved with a second cleaning device, and the second cleaning device can slide along the first stationary contact plate and the second stationary contact plate.

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