Low-voltage apparatus load change-over switch

Abstract

The invention relates to the technical field of electric appliance switches, in particular to a low-voltage electric appliance load change-over switch, which comprises a mounting shell, a knob, a rotating shaft and a contact mechanism, and is characterized in that the rotating shaft comprises a first-section shaft and a third-section shaft, the first-section shaft is rotationally connected with the mounting shell, two ends of the first-section shaft extend out of the mounting shell, one end of the first-section shaft is connected with the knob, and the other end of the first-section shaft is connected with the contact mechanism; n mounting seats are arranged on one side surface, far away from the knob, of the mounting shell, wherein N is greater than or equal to 2; according to the invention, the rotating shaft in the change-over switch is arranged to be of a detachable structure, and the angle locking assembly is matched to lock the moving contact with the changed angle, so that the switching requirements of the change-over switch in different load circuits are met, and the control capability of the change-over switch and the applicability of the change-over switch to different load circuits are improved; according to the scheme, the rotating shaft is disassembled and assembled by adopting a hole-shaft matching structural form, so that the change-over switch is convenient to process, assemble and disassemble, and the production cost and the failure rate of the change-over switch are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical switches, and specifically to a low-voltage electrical load transfer switch. Background Art

[0002] A low-voltage electrical transfer switch is an electrical switch used to switch different power sources or loads in a voltage circuit. The low-voltage electrical transfer switch is often used in the control system of electrical equipment to ensure the stability of the low-voltage circuit, improve the safety of the electrical system, and optimize the load distribution. The core structure of a conventional transfer switch is a camshaft, static contacts, and moving contacts. Among them, multiple layers are provided on the camshaft according to the shape of the camshaft or different cam arrangement sequences. When the camshaft rotates, the moving contacts at different positions are connected to or separated from the static contacts, thereby completing the on-off control of multiple circuit systems. Therefore, the on-off control of different low-voltage load circuit systems can be achieved by changing the shape of the camshaft or the arrangement sequence of each layer of cams. However, for a conventional transfer switch, the multi-layer cam structure on its camshaft is immutable and non-adjustable. During the actual installation process, it is necessary to select the type according to the low-voltage load circuit system to meet the control requirements of the circuit system. Therefore, the control ability of the transfer switch after leaving the factory is limited.

[0003] In response to the above problems, some solutions have been proposed in the prior art. For example, the invention patent with the patent application number CN202311449595.4 provides a universal transfer switch. The invention installs a rotating shaft and an adjusting screw in the switch body. The adjusting screw is rotatably installed inside the rotating shaft, and a plurality of screw sleeves are threadedly connected to the adjusting screw. A matching component is provided on the screw sleeve, and the screw sleeve is slidably connected to the rotating shaft. By controlling the rotation of the adjusting screw to adjust the sliding position of the screw sleeve, the matching component is connected to the cam mechanism, thereby driving different numbers of layers and different numbers of cam mechanisms to rotate, so as to control the closing and opening of the contact mechanisms at different positions, realizing the complex control of multiple circuits, and improving the control ability or operation efficiency of the transfer switch. However, there are many transmission components in this technical solution, and the structure is relatively complex, resulting in an increase in the costs of production, assembly, and processing. At the same time, the cut-off response of this technical solution after the working temperature of the circuit system exceeds the rated temperature will be affected by the response speed of the transmission structure, which is not conducive to protecting the safety of the circuit system and the transfer switch. Summary of the Invention

[0004] The purpose of the present invention is to provide a low-voltage electrical load transfer switch to solve the problem that the transfer switch cannot perform corresponding control conversion in combination with the actual circuit system after leaving the factory, resulting in limited control ability of the transfer switch, and at the same time solve the problems existing in the prior art solutions.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A low-voltage electrical appliance load transfer switch, comprising a mounting shell, a knob, a rotating shaft and a contact mechanism. The rotating shaft includes a single-section shaft and a three-section shaft. The single-section shaft is rotatably connected to the mounting shell, and both ends of the single-section shaft extend outside the mounting shell. One end of the single-section shaft is connected to the knob. On one side of the mounting shell away from the knob, there are at least two mounting seats. The end of the single-section shaft away from the knob extends into the mounting seat that fits the mounting shell. The side of the single-section shaft away from the knob is detachably and coaxially connected to the three-section shaft, and an angle locking component is provided between the single-section shaft and the three-section shaft. The end of the three-section shaft away from the single-section shaft is rotatably connected to a rear cover, and the mounting shell, the rear cover and the multiple mounting seats are bolted together; the contact mechanism includes a moving contact and a static contact. Two groups of static contacts are symmetrically arranged in each of the multiple mounting seats. The number of static contacts in each group is 2, and the static contacts in the same group are symmetric and not in contact with each other. The two ends of the static contact are respectively located inside and outside the mounting seat. Two moving contacts are symmetrically arranged on the outer side walls of the single-section shaft and the three-section shaft. Within the range where the single-section shaft rotates 90°, each moving contact only contacts the two static contacts in the same group, and the length of the moving contact is greater than the gap between the two static contacts in the same group.

[0007] By setting the single-section shaft and the three-section shaft to be detachably connected and providing an angle locking component between the single-section shaft and the three-section shaft, when setting the transfer switch in different low-voltage load circuit systems, the single-section shaft and the three-section shaft can be removed, the relative angle between the moving contact on the single-section shaft and the moving contact on the three-section shaft can be adjusted, and then the angle between the moving contact on the single-section shaft and the moving contact on the three-section shaft can be locked through the angle locking component, so as to meet the switching requirements of different load circuits, improve the control ability of the transfer switch and the applicability to different load circuits; the combination of this solution is simple, easy to process and produce, thus reducing the production cost and failure rate of the transfer switch.

[0008] Preferably, at least one two-section shaft is coaxially arranged between the single-section shaft and the three-section shaft. The single-section shaft, the two-section shaft and the three-section shaft are all detachably connected, and angle locking components are provided between the single-section shaft and the adjacent two-section shaft, between adjacent two-section shafts, and between the three-section shaft and the adjacent two-section shaft. And the total number of the single-section shaft, the two-section shaft and the three-section shaft is the same as the total number of the mounting seats. Two moving contacts are symmetrically arranged on the outer side wall of the two-section shaft. By providing a two-section shaft between the single-section shaft and the three-section shaft, the connection positions of the transfer switch are increased, so as to meet more complex low-voltage load circuits, and improve the control ability and operation efficiency of the transfer switch.

[0009] Preferably, the outer sidewalls of the shaft segments of the first-stage shaft extending into the mounting base, the outer sidewall of the second-stage shaft, and the outer sidewalls of the shaft segments of the third-stage shaft extending into the mounting base are all regular prismatic shapes, the number of edges is twice the number of mounting bases, a pair of mounting grooves are symmetrically arranged on the outer sidewalls of the first-stage shaft, the second-stage shaft, and the third-stage shaft, and multiple said mounting grooves are all located within the prism faces. The moving contact is arranged in the mounting groove, and the outer sidewall of the moving contact sinks 1-2 mm below the prism face. Pressure components are arranged in multiple said mounting bases. One end of the pressure component is connected to the mounting base, and the other end is press-connected to two static contacts in the same group. The pressure component is used to provide pressure towards the mounting groove for the two static contacts in the same group.

[0010] By setting the outer sidewalls of the shaft segments of the first-stage shaft extending into the mounting base, the outer sidewall of the second-stage shaft, and the outer sidewalls of the shaft segments of the third-stage shaft extending into the mounting base as regular prismatic shapes, and arranging a pressure component in the mounting base, the static contacts are kept in contact with the prism face under the action of the pressure component. When the knob is rotated to switch to different gears, the static contacts undergo elastic deformation to avoid jamming between the rotating shaft and the static contacts, ensuring the smoothness of gear shifting; after the gear shifting operation is completed, the elastic potential energy of the static contacts is released, and they are in contact with the outer sidewall of the rotating shaft under the pressure of the pressure component, thus avoiding problems such as dislocation and gear jumping of the changeover switch in a vibrating environment and ensuring the stability and safety of the changeover switch.

[0011] Preferably, the angle locking component includes a frustum. Embedding holes are provided on the end faces of the first-stage shaft away from the knob and the end faces of the second-stage shaft away from the first-stage shaft. Frustums are provided on the end faces of the second-stage shaft close to the first-stage shaft and the end faces of the third-stage shaft close to the second-stage shaft. The embedding holes and the frustums are both regular polygonal shapes, and are concentric and similar to the regular polygonal shape of the outer sidewall of the second-stage shaft. An interference fit is provided between the embedding hole and the frustum. By setting the regular polygonal frustum and the embedding hole as the angle locking structure between the shaft segments, and the interference fit between the frustum and the embedding hole, the structural complexity and production cost of the changeover switch are reduced; further, when performing angle conversion between the first-stage shaft, the second-stage shaft, and the third-stage shaft, the frustum is pulled out of the embedding hole, and after switching to the required angle, the frustum is inserted into the embedding hole, which is convenient for construction personnel to operate; since an interference fit is provided between the frustum and the previous embedding hole, axial relative displacement between the shaft segments is avoided, and because both the frustum and the embedding hole are regular polygonal shapes, relative axial rotation between the shaft segments is avoided, ensuring the accuracy of each gear position of the changeover switch.

[0012] Preferably, the pressure assembly includes a spring and an insulating block. A type III mounting hole coaxial with the shaft section is provided on each of the plurality of mounting seats. The type III mounting hole completely penetrates the mounting seat. Two type IV mounting holes are provided on each of the plurality of mounting seats. The type IV mounting hole extends to the outside of the mounting seat and into the type III mounting hole, and the axis of the type IV mounting hole intersects and is perpendicular to the axis of the type III mounting hole. The spring is coaxially mounted in the type IV mounting hole. An insulating block is provided at one end of each of the plurality of springs close to the type III mounting hole. The side surface of the insulating block away from the spring is in contact with two static contacts in the same group. Cover plates are symmetrically arranged on the outer side wall of the mounting seat, and one end away from the type III mounting hole is connected to the cover plate.

[0013] When the rotary knob is rotated to switch to different gears, since the static contact needs to undergo elastic deformation to prevent the rotation shaft from jamming with the static contact, if the static contact undergoes plastic deformation during the gear shifting process, after the gear shifting operation is completed, it is easy to occur that the static contact and the moving contact cannot be connected, which may easily generate electric arcs or poor contact. Therefore, by providing a spring and an insulating block in the mounting seat, the static contact is kept in contact with the prism surface or the moving contact under the elastic force of the spring, thus avoiding the unstable connection between the static contact and the moving contact, ensuring the stability and safety of the change-over switch; at the same time, it avoids problems such as dislocation and gear jumping of the change-over switch in a vibrating environment, further ensuring the stability and safety of the change-over switch.

[0014] Preferably, the insulating block includes a connecting portion, a pressing portion and an embedding portion. The connecting portion is coaxially connected to the spring. One side surface of the pressing portion is connected to the connecting portion and abuts against the spring, and the other side surface abuts against two static contacts in the same group. The embedding portion is located at the center of this side surface and extends into the mounting groove. A type I mounting hole and a type II mounting hole are provided in the middle of each of the plurality of mounting grooves. The diameters and depths of the type I mounting hole and the type II mounting hole are D1, H1 and D2, H2 respectively. Each of the plurality of moving contacts is embedded in the type I mounting hole. A through hole is provided in the middle of each of the plurality of moving contacts. The diameter of the through hole is D3. Wherein, D3 = D2 < D1, H1 < H2. A sliding rod is coaxially and slidably connected in the type II mounting hole. One end of the sliding rod abuts against the embedding portion, and the other end extends into the type II mounting hole.

[0015] When the low-voltage load circuit is working, the temperatures of the connected moving contact and static contact will gradually rise. Especially when the load of the low-voltage electrical appliance increases, a short circuit occurs in the circuit, or the power grid is unstable, and the current in the circuit system increases, it is easy for the temperature between the interconnected moving contact and static contact to exceed the rated operating temperature, resulting in damage to the changeover switch. Therefore, by arranging a slide bar in the rotating shaft, when the temperature of the moving contact rises, the temperature of the moving contact is transmitted into the type-II mounting hole, the temperature in the type-II hole rises, pushing the slide bar to move outward from the rotating shaft, and then pushing the embedding part out of the through hole. After the static contact loses the pressure of the spring, it gradually resets until the static contact resets outside the mounting groove, and the static contact disconnects from the moving contact, thereby cutting off the circuit and preventing the circuit from overheating and causing damage to the circuit, low-voltage electrical appliance or changeover switch, ensuring the safety of the changeover switch and the circuit system.

[0016] Preferably, an annular card slot is formed on the outer side wall of the shaft section of the first shaft located inside the mounting shell. Two reed pieces are symmetrically arranged inside the mounting shell. Each reed piece includes a fixed end and a movable end. The fixed end is connected to the mounting seat by bolts, and the movable end is embedded in the card slot. In the relaxed state of the reed pieces, the vertical projections of multiple static contacts do not intersect with the vertical projection of the moving contact.

[0017] When the static contact is connected to the moving contact, the spring applies a spring force to the static contact through the pressing part, pressing the static contact into the mounting groove. Although a slide bar is arranged in the rotating shaft to prevent the circuit system and the changeover switch from overheating, after the static contact is affected by high temperature, problems such as a decrease in elasticity or plastic deformation are likely to occur. At this time, after the slide bar pushes the embedding part out of the through hole, the static contact is likely to have a problem of not disconnecting from the moving contact, thus unable to ensure the safety of the circuit system. Therefore, by arranging a card slot on the first shaft and arranging reed pieces inside the mounting shell, when the operating temperature of the moving contact exceeds the rated temperature, the high-pressure gas in the type-II mounting hole pushes the slide bar, the slide bar pushes the embedding part out of the through hole, the rotating shaft loses axial limit, the elastic potential energy of the reed pieces is released, the rotating shaft moves in the direction of the knob under the elastic force of the reed pieces, and the moving contact and the static contact are misaligned axially of the rotating shaft, thus avoiding the problem that the static contact and the moving contact do not disconnect after the temperature of the moving contact exceeds the rated temperature, and ensuring the safety of the changeover switch and the circuit system.

[0018] Preferably, airtight cavities are provided in the first shaft, the second shaft and the third shaft. Multiple airtight cavities communicate with the mounting grooves on both sides. The length of the airtight cavity is less than the length of the moving contact, and the width of the airtight cavity is less than the diameter of the type-II mounting hole.

[0019] Since there are two moving contacts on each of the first-stage shaft, the second-stage shaft and the third-stage shaft, and the symmetric moving contacts respectively control two circuit systems. When the operating temperature of one circuit system exceeds the rated temperature, the slide bar on that side will pull out the embedding part on that side from the through hole, while the other side still maintains the state where the embedding part is embedded in the through hole. The axial limit of the rotating shaft cannot be released, thus unable to ensure the safety of the circuit system. Although the two type-II mounting holes can be connected, the two connected type-II mounting holes only rely on the temperature of the moving contact on one side to increase the air pressure in the type-II mounting hole, and the required temperature is relatively high, which is likely to exceed the rated temperature of the moving contact. Therefore, by providing an airtight cavity in the rotating shaft, the contact area between the airtight cavity and the moving contact is larger, which can better absorb the temperature of the moving contact. At the same time, the airtight cavity communicates with the two type-II mounting holes on both sides. After the temperature of the moving contact on one side rises, the gas pressure in the airtight cavity gradually increases, and simultaneously pushes the slide bars on both sides to move towards the outside of the rotating shaft, thereby ensuring that when the operating temperature of one moving contact exceeds the rated temperature, the embedding parts on both sides are pushed out of the through hole, and then the axial limit of the rotating shaft is released, ensuring the safety of the change-over switch and the circuit system.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. By setting the rotating shaft in the change-over switch as a detachable structure and cooperating with the angle locking component to lock the moving contact after the angle is changed, the present invention meets the switching requirements of the change-over switch in different load circuits, improves the control ability of the change-over switch and the applicability to different load circuits; and this solution adopts the structural form of hole-shaft fit for the disassembly and assembly of the rotating shaft, which is convenient for the processing, assembly and disassembly of the change-over switch, thereby reducing the production cost and failure rate of the change-over switch.

[0022] 2. By setting the outer side wall of the rotating shaft as a regular polygonal prism shape and providing springs and insulating blocks in the mounting seat, the static contact is kept in contact with the prism surface or the moving contact under the elastic force of the spring, thus avoiding the unstable connection between the static contact and the moving contact, ensuring the stability and safety of the change-over switch; at the same time, it avoids problems such as dislocation and gear jumping of the change-over switch in a vibrating environment, further ensuring the stability and safety of the change-over switch.

[0023] 3. By providing an airtight cavity and slide bars in the rotating shaft, when the temperature in the circuit system rises, the temperature of the moving contact is transmitted into the airtight cavity, and the high-pressure gas in the airtight cavity pushes the slide bars on both sides to move towards the outside of the rotating shaft at the same time, and then the embedding part is pushed out of the through hole. After the static contact loses the pressure of the spring, it gradually resets and retracts outside the mounting groove, and the static contact disconnects from the moving contact, thereby cutting off the circuit and avoiding damage to the circuit, low-voltage electrical appliances or the change-over switch due to excessive circuit temperature, ensuring the safety of the change-over switch and the circuit system.

[0024] 4. In the present invention, a clamping groove is provided on a section of the shaft, and a reed is provided inside the mounting shell. When the operating temperature of the moving contact exceeds the rated temperature, the high-pressure gas in the airtight cavity pushes the sliding rod to move outward from the rotating shaft, and then the embedding part is pushed out of the through hole. The rotating shaft loses its axial limit, and the elastic potential energy of the reed is released. Under the elastic force of the reed, the rotating shaft moves towards the direction of the knob, and the moving contact and the static contact are misaligned axially on the rotating shaft, thereby avoiding the problem that the connection between the static contact and the moving contact is not disconnected after the temperature of the moving contact exceeds the rated temperature, and ensuring the safety of the change-over switch and the circuit system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram of the overall structure of the low-voltage electrical load change-over switch of the present invention;

[0026] Figure 2 is an exploded view of the low-voltage electrical load change-over switch of the present invention;

[0027] Figure 3 is a top view of the low-voltage electrical load change-over switch of the present invention;

[0028] Figure 4 is Figure 3 a full sectional view taken along line A-A in

[0029] Figure 5 is Figure 4 a partially enlarged view at D in

[0030] Figure 6 is a schematic diagram of the state of the low-voltage electrical load change-over switch of the present invention under high-temperature protection;

[0031] Figure 7 is Figure 6 a partially enlarged view at E in

[0032] Figure 8 is Figure 3 a full sectional view taken along line B-B in

[0033] Figure 9 is Figure 3 a full sectional view taken along line C-C in

[0034] Figure 10 is a schematic diagram of the half-sectional structure of the rotating shaft of the present invention;

[0035] Figure 11 is a schematic diagram of the structure of the two-section shaft of the present invention;

[0036] Figure 12 is an exploded view of another embodiment of the rotating shaft of the present invention.

[0037] In the figure: 1. Knob; 2. Panel; 3. Mounting shell; 4. Reed; 401. Fixed end; 402. Movable end; 5. Rotating shaft; 501. First section of the shaft; 5011. Card slot; 5012. Cutting surface; 5013. First connecting surface; 5014. Second connecting surface; 5015. Third connecting surface; 5016. Mounting groove; 5017. Type-I mounting hole; 5018. Type-II mounting hole; 5019. Airtight cavity; 502. Second section of the shaft; 5021. Frustum; 5022. Embedding hole; 503. Third section of the shaft; 6. First mounting seat; 601. Type-III mounting hole; 602. Type-IV mounting hole; 7. Second mounting seat; 8. Third mounting seat; 9. Rear cover; 10. Stationary contact; 11. Insulating block; 1101. Connecting part; 1102. Pressing part; 1103. Embedding part; 12. Spring; 13. Cover plate; 14. Moving contact; 1401. Through hole; 15. Slide bar. Detailed implementation manner

[0038] Please refer to Figures 1 to 11 , the present invention provides a low-voltage electrical load conversion switch, and the technical solution is as follows:

[0039] As an implementation manner of the present invention, this implementation manner is a 12-position four-gear conversion switch. Please refer to Figure 1 and Figure 2 , a low-voltage electrical load conversion switch, including a mounting shell 3, a knob 1, a rotating shaft 5 and a contact mechanism. The +X end face of the mounting shell 3 is fixedly installed with a panel 2, and the +X end face of the panel 2 is provided with gear position markings. The -X end face of the mounting shell 3 is provided with three mounting seats. The three mounting seats are the first mounting seat 6, the second mounting seat 7 and the third mounting seat 8 along the -X direction respectively. The -X end face of the third mounting seat 8 is provided with a rear cover 9, and the rear cover 9 is fixedly connected to the mounting shell 3 through bolts. The rotating shaft 5 includes a first section of the shaft 501, a second section of the shaft 502 and a third section of the shaft 503. The first section of the shaft 501 is rotatably connected to the mounting shell 3, and both ends of the first section of the shaft 501 extend outside the mounting shell 3. The +X end of the first section of the shaft 501 is fixedly connected to the knob 1 through bolts. The -X end of the first section of the shaft 501 extends into the mounting seat that fits with the mounting shell 3. The -X end of the third section of the shaft 503 is rotatably connected to the rear cover 9.

[0040] Please refer to Figure 2 , Figure 10 and Figure 11, the outer sidewalls of the shaft segments of the first-stage shaft 501 extending into the mounting base, the outer sidewall of the second-stage shaft 502, and the outer sidewalls of the shaft segments of the third-stage shaft 503 extending into the mounting base are all regular octagonal prisms. Embedding holes 5022 are provided on the -X end faces of the first-stage shaft 501 and the second-stage shaft 502. Frustums 5021 are provided on the +X end faces of the second-stage shaft 502 and the third-stage shaft 503. The embedding holes 5022 and the frustums 5021 are both concentric and similar to the outer sidewall of the second-stage shaft 502, and there is an interference fit of H7 / n6 between the embedding holes 5022 and the frustums 5021. The prism faces of the first-stage shaft 501, the second-stage shaft 502, and the third-stage shaft 503 are each divided into 2 cutting surfaces 5012, 2 first connecting surfaces 5013, 2 second connecting surfaces 5014, and 2 third connecting surfaces 5015, and the prism faces of the same type are symmetrically arranged. Mounting grooves 5016 are provided on the first connecting surfaces 5013 of the first-stage shaft 501, the second connecting surfaces 5014 of the second-stage shaft 502, and the third connecting surfaces 5015 of the third-stage shaft 503. The sidewalls of the mounting grooves 5016 in the -X direction are all inclined surfaces. A first-type mounting hole 5017 and a second-type mounting hole 5018 are provided at the centers of the bottoms of the mounting grooves 5016. The diameter and depth of the first-type mounting hole 5017 are 7.0 mm and 4.0 mm respectively, and the diameter and depth of the second-type mounting hole 5018 are 4.0 mm and 8.0 mm respectively. The two second-type mounting holes 5018 within the same shaft do not penetrate each other. Airtight cavities 5019 are provided within the first-stage shaft 501, the second-stage shaft 502, and the third-stage shaft 503. The airtight cavities 5019 are located at the centers of the bottoms of the mounting grooves 5016, and the airtight cavities 5019 communicate with the mounting grooves 5016 on both sides. The length of the airtight cavities 5019 in the X direction is less than the length of the mounting grooves 5016 in the X direction, and the width of the airtight cavities 5019 in the Y direction is less than the diameter of the second-type mounting holes 5018.

[0041] Please refer to Figures 3 to 5 , Figure 10, on the first mounting base 6, the second mounting base 7, and the third mounting base 8, there are all type-three mounting holes 601 coaxial with the first-stage shaft 501, and the type-three mounting holes 601 completely penetrate through the corresponding mounting base; on the +Z and -Z end faces of the first mounting base 6, the second mounting base 7, and the third mounting base 8, there are all type-four mounting holes 602. Both ends of the multiple type-four mounting holes 602 respectively extend to the outside of the corresponding mounting base and into the type-three mounting holes 601. The axis lines of the multiple type-four mounting holes 602 intersect and are perpendicular to the axis line of the type-three mounting holes 601. On the +Z and -Z end faces of the first mounting base 6, the second mounting base 7, and the third mounting base 8, there are fixedly installed cover plates 13. Inside the type-four mounting holes, there are coaxially installed springs 12. One ends of the springs 12 away from the type-three mounting holes 601 are all in contact with the corresponding cover plates 13. One ends of the springs 12 away from the cover plates 13 are all provided with insulating blocks 11. The insulating blocks 11 include a connecting portion 1101, a pressing portion 1102, and an embedding portion 1103. The connecting portion 1101 is coaxially connected with the spring 12. One side surface of the pressing portion 1102 is connected to the connecting portion 1101, and this side surface is in contact with one end of the spring 12 away from the cover plate 13. The embedding portion 1103 is arranged on the other side surface of the pressing portion 1102.

[0042] Please refer to Figure 2 , Figure 3 , Figure 4 , Figure 8 and Figure 10 , the contact mechanism includes a moving contact 14 and a static contact 10. Inside each mounting groove 5016, there is a moving contact 14. One end of the moving contact 14 is embedded in the type-one mounting hole 5017 with an interference fit of H7 / n6. The moving contact 14 does not extend outside the mounting groove 5016, and the moving contact 14 is recessed 1.0 mm below the prism surface. On the moving contacts 14, there are all through holes 1401. The through holes 1401 are coaxial and equal to the type-two mounting holes 5018, and the through holes 1401 completely penetrate through the moving contacts 14. A sliding rod 15 is slidably connected inside the type-two mounting holes 5018. The fit between the type-two mounting holes 5018 and the sliding rod 15 is a clearance fit of H7 / h6. One end of the sliding rod 15 extends into the through hole 1401 and is in contact with the embedding portion 1103. A sealing ring is coaxially arranged inside the through hole 1401. The sealing ring is elastically matched with the sliding rod 15. The airtight cavity 5019 is in a closed state after the moving contact 14, the sliding rod 15, and the sealing ring are installed.

[0043] Please refer to Figure 1 and Figure 2, two sets of static contacts 10 are provided in each of the first mounting base 6, the second mounting base 7, and the third mounting base 8. The two sets of static contacts 10 in the same mounting base are symmetric with respect to the XY plane. The number of static contacts 10 in each set is 2, and the static contacts 10 in the same set are not connected to each other. Moreover, the two static contacts 10 in the same set are symmetric with respect to the XZ plane. Both ends of the multiple static contacts 10 are located on the inner and outer sides of the corresponding mounting base respectively. The end parts of each set of static contacts 10 extending into the type-three mounting holes 601 respectively correspond to a moving contact 14 and an insulating block 11. The Y-direction width of the embedding part 1103 is smaller than the gap between the corresponding set of static contacts 10. The Y-direction width of the pressing part 1102 is larger than the gap between the corresponding set of static contacts 10. When a section of the shaft 501 is at the right dead center, the two embedding parts 1103 in the same mounting base and the type-two mounting holes 5018 are located in the same YZ plane. The four static contacts 10 in the first mounting base 6 are respectively the 1st position, the 2nd position, the 3rd position, and the 4th position. Among them, the four static contacts 10 in the second mounting base 7 are respectively the 5th position, the 6th position, the 7th position, and the 8th position. The four static contacts 10 in the third mounting base 8 are respectively the 9th position, the 10th position, the 11th position, and the 12th position. Among them, the 1st position, the 5th position, and the 9th position are all in the +Y+Z direction, the 3rd position, the 7th position, and the 11th position are all in the +Y-Z direction, the 2nd position, the 6th position, and the 10th position are all in the -Y+Z direction, and the 4th position, the 8th position, and the 12th position are all in the -Y-Z direction.

[0044] Please refer to Figure 2 , Figure 6 and Figure 7 , an annular clamping groove 5011 is formed on the outer side wall of the shaft section of the section of the shaft 501 located in the mounting shell 3. Two reed pieces 4 are symmetrically arranged in the Z direction in the mounting shell 3. The reed piece 4 includes a fixed end 401 and a movable end 402. The fixed ends 401 of the two reed pieces 4 are both connected to the mounting base by bolts. The movable ends 402 of the two reed pieces 4 are both embedded in the clamping groove 5011. When none of the multiple embedding parts 1103 are embedded in the through holes 1401, the Z-direction projections of the multiple static contacts 10 do not intersect with the vertical projection of the moving contact 14.

[0045] Working principle: Please refer to Figure 1 , Figures 3 to 5 , Figure 10, at this time, it is in the first gear position. The two first connecting surfaces 5013 on the first shaft 501 are both parallel to the XY plane. The two embedding parts 1103 in the first mounting seat 6 extend into the through holes 1401 of the two moving contacts 14 on the first shaft 501. The two embedding parts 1103 in the first mounting seat 6 are respectively in contact with the two sliding rods 15 in the first shaft 501. The four static contacts 10 in the first mounting seat 6 are respectively pressed into the mounting grooves 5016 under the spring force of the springs 12 and are respectively in contact with the moving contacts 14. At this time, position 1 is connected to position 2, and position 3 is connected to position 4; the two second connecting surfaces 5014 on the second shaft 502 and the two third connecting surfaces 5015 on the third shaft 503 are parallel to the XY plane. At this time, positions 5 and 6, positions 7 and 8, positions 9 and 10, and positions 11 and 12 are all in the disconnected state; when it is necessary to switch to the neutral gear, second gear or third gear, just rotate the knob 1 in the corresponding direction to the corresponding gear position, which will not be elaborated here. Please refer to Figures 4 to 7, when in the first gear position, after the circuit system runs for a long time, the temperatures of the two moving contacts 14 on the first shaft 501 gradually rise. Since the airtight cavity 5019 in the first shaft 501 is connected to the two moving contacts 14 on the first shaft 501, the temperature and air pressure in the airtight cavity 5019 in the first shaft 501 gradually rise. The two sliding rods 15 in the first shaft 501 are affected by the gas pressure in the airtight cavity 5019. When the air pressure in the airtight cavity 5019 in the first shaft 501 is equal to or greater than the pressure of the spring 12, the distances between the two sliding rods 15 in the first shaft 501 gradually increase under the action of the air pressure, and respectively push the insulating blocks 11 in the first mounting seat 6 to move away from the moving contacts 14 until the two sliding rods 15 in the first shaft 501 completely push out the two embedding parts 1103 through the through holes 1401. After that, the first rotating shaft 5 loses its axial limiting function, and the reed 4 releases its own elastic potential energy. The first shaft 501 moves in the +X direction under the elastic force of the reed 4, and at the same time drives the second shaft 502 and the third shaft 503 to move in the +X direction until the reed 4 abuts against the inner side wall of the mounting shell 3. At this time, the first shaft 501 moves to the left dead point, and the two moving contacts 14 on the first shaft 501 lose connection with all four static contacts 10 in the first mounting seat 6, the 1st position is disconnected from the 2nd position, and the 3rd position is disconnected from the 4th position. Thus, the high-temperature protection of the change-over switch is completed; to ensure safety, the operator needs to turn the knob 1 back to the zero gear position. It should be noted that to avoid reconnecting the circuit before the temperature of the circuit system has dropped, when the temperature in the airtight cavity 5019 in the first shaft 501 has not dropped to the safe temperature range, press the knob 1 in the -X direction to the right dead point of the first shaft 501, and then turn the knob 1 to the first gear position. At this time, the temperature in the airtight cavity 5019 in the first shaft 501 has not dropped to the safe temperature range, and the two sliding rods 15 in the first shaft 501 are in the extended state. The two embedding parts 1103 in the first connecting seat cannot extend into the through holes 1401, so the axial position of the first shaft 501 cannot be locked, thus ensuring the safety of the circuit system.

[0046] As another embodiment of the present invention, please refer to Figure 12, different from the above embodiments, this embodiment is a 12-bit 3-position changeover switch. In the previous embodiment, the cut surfaces 5012, the first connection surface 5013, the second connection surface 5014, and the third connection surface 5015 of the first-stage shaft 501, the second-stage shaft 502, and the third-stage shaft 503 are all flush with each other. In this embodiment, the cut surface 5012 of the first-stage shaft 501, the first connection surface 5013 of the second-stage shaft 502, and the second connection surface 5014 of the third-stage shaft 503 are in the same plane, the first connection surface 5013 of the first-stage shaft 501, the second connection surface 5014 of the second-stage shaft 502, and the first connection surface 5013 of the third-stage shaft 503 are in the same plane, the second connection surface 5014 of the first-stage shaft 501, the cut surface 5012 of the second-stage shaft 502, and the third connection surface 5015 of the third-stage shaft 503 are in the same plane, and the third connection surface 5015 of the first-stage shaft 501, the third connection surface 5015 of the second-stage shaft 502, and the cut surface 5012 of the third-stage shaft 503 are in the same plane; in the zero position, all moving contacts 14 and stationary contacts 10 are in the off state. In the first position, the positions 1 and 2, 3 and 4, 5 and 6, 7 and 8 are in the connected state, and the positions 9 and 10, 11 and 12 are in the off state; in the second position, the positions 1 and 2, 3 and 4, 5 and 6, 7 and 8 are in the off state, and the positions 9 and 10, 11 and 12 are in the connected state; it should be noted that in this embodiment, when in the first position, the embedding parts 1103 in the first mounting seat 6 and the second mounting seat 7 both have a limiting effect on the rotating shaft 5. Therefore, the airtight cavities 5019 in the first-stage shaft 501 and the second-stage shaft 502 need to be connected (not shown in the figure) to share the air pressure and ensure the safety of the circuit system.

[0047] The above has described in detail two specific embodiments of the present invention in conjunction with the accompanying drawings, but the present invention is not limited to the above-described embodiments. For those skilled in the art, without departing from the principles and ideas of the present invention, various changes, modifications, substitutions, and variations made to these embodiments should still fall within the protection scope of the present invention.

Claims

1. A low-voltage electrical load transfer switch, comprising a mounting housing (3), a knob (1), a rotating shaft (5) and a contact mechanism, characterized in that: The rotating shaft (5) comprises a first section shaft (501) and a third section shaft (503); the first section shaft (501) is rotatably connected to the mounting shell (3), and both ends of the first section shaft (501) extend outside the mounting shell (3); one end of the first section shaft (501) is connected to the knob (1); a side of the mounting shell (3) away from the knob (1) is provided with N mounting seats, wherein N is greater than or equal to 2; one end of the first section shaft (501) away from the knob (1) extends into a mounting seat that fits the mounting shell (3); a side of the first section shaft (501) away from the knob (1) is coaxially detachably connected to the third section shaft (503); an angle locking assembly is provided between the first section shaft (501) and the third section shaft (503); one end of the third section shaft (503) away from the first section shaft (501) is rotatably connected to the mounting shell (3); A rear cover (9) is connected, and the mounting shell (3), the rear cover (9) and a plurality of mounting seats are bolted together; the contact mechanism comprises a moving contact (14) and a stationary contact (10); two groups of stationary contacts (10) are symmetrically arranged in the plurality of mounting seats, and each group of stationary contacts (10) has two members, and the stationary contacts (10) in the same group are symmetrical to each other and not connected, and the two ends of the stationary contact (10) are respectively located on the inner and outer sides of the mounting seat; two moving contacts (14) are symmetrically arranged on the outer side walls of the one-section shaft (501) and the three-section shaft (503); within a range of 90° rotation of the one-section shaft (501), each moving contact (14) only contacts with the two stationary contacts (10) in the same group, and the length of the moving contact (14) is greater than the gap between the two stationary contacts (10) in the same group.

2. A low voltage electrical appliance load transfer switch according to claim 1, characterized in that: At least one second-section shaft (502) is coaxially arranged between the first-section shaft (501) and the third-section shaft (503), and the total number of the first-section shaft (501), the second-section shaft (502) and the third-section shaft (503) is the same as the total number of the mounting seats, and two moving contacts (14) are symmetrically arranged on the outer side wall of the second-section shaft (502).

3. A low voltage electrical appliance load transfer switch according to claim 2, characterized in that: The outer wall of the shaft section extending from the first section of the shaft (501) to the mounting seat, the outer wall of the second section of the shaft (502), and the outer wall of the shaft section extending from the third section of the shaft (503) to the mounting seat are all regular polygonal prisms, with 2N+2 edges. A pair of mounting grooves (5016) are symmetrically arranged on the outer walls of the first section of the shaft (501), the second section of the shaft (502), and the third section of the shaft (503). The plurality of mounting grooves (5016) are all located within the edge surface. The moving contact (14) is arranged in the mounting groove (5016), and the outer wall of the moving contact (14) is sunk 1 to 2 mm below the edge surface. A pressure assembly is arranged in the plurality of mounting seats. One end of the pressure assembly is connected to the mounting seat, and the other end is crimped to two stationary contacts (10) in the same group. The pressure assembly is used to provide pressure toward the mounting groove (5016) for the two stationary contacts (10) in the same group.

4. A low voltage electrical appliance load transfer switch according to claim 3, characterized in that: The angle locking assembly comprises a prism (5021), an embedding hole (5022) is provided on the end surface of the first section shaft (501) away from the knob (1) and the end surface of the second section shaft (502) away from the first section shaft (501), a prism (5021) is provided on the end surface of the second section shaft (502) close to the first section shaft (501) and the end surface of the third section shaft (503) close to the second section shaft (502), the embedding hole (5022) and the prism (5021) are both regular polygonal and are concentric and similar to the regular polygonal shape of the outer wall of the second section shaft (502), and the embedding hole (5022) and the prism (5021) are in interference connection.

5. A low voltage electrical appliance load transfer switch according to claim 3, characterized in that: The pressure assembly comprises a spring (12) and an insulating block (11); a plurality of the mounting seats are each provided with a three-type mounting hole (601) coaxial with a section of the shaft (501); the three-type mounting hole (601) completely penetrates the mounting seat; a plurality of the mounting seats are each provided with two four-type mounting holes (602); the four-type mounting holes (602) extend to the outside of the mounting seat and into the three-type mounting holes (601); and the axis centerline of the four-type mounting hole (602) is aligned with the axis centerline of the three-type mounting hole (601). 1) and their axis lines intersect and are perpendicular, the spring (12) is coaxially installed in the four-type mounting hole (602), and an insulating block (11) is provided at one end of the plurality of springs (12) close to the three-type mounting hole (601), and a side of the insulating block (11) away from the spring (12) is in contact with two static contacts (10) in the same group, and a cover plate (13) is symmetrically arranged on the outer side wall of the mounting seat, and the end away from the three-type mounting hole (601) is connected to the cover plate (13).

6. A low voltage electrical appliance load transfer switch according to claim 5, characterized in that: The insulating block (11) comprises a connecting portion (1101), a pressing portion (1102) and an embedding portion (1103); the connecting portion (1101) is coaxially connected to the spring (12); one side of the pressing portion (1102) is connected to the connecting portion (1101) and abuts against the spring (12); the other side abuts against two stationary contacts (10) in the same group; the embedding portion (1103) is located at the center of the side and extends into the mounting groove (5016); a plurality of the mounting grooves (5016) are provided with a first-type mounting hole (5017) and a second-type mounting hole (5018) in the middle thereof. The diameter and depth of the type-one mounting hole (5017) and the type-two mounting hole (5018) are respectively D1 and H1 and D2 and H2. The plurality of moving contacts (14) are embedded in the type-one mounting hole (5017). A through hole (1401) is provided in the middle of the plurality of moving contacts (14). The diameter of the through hole (1401) is D3, wherein D3=D2<D1, H1<H2. A sliding rod (15) is coaxially slidably connected in the type-two mounting hole (5018). One end of the sliding rod (15) is in contact with the embedded portion (1103), and the other end extends into the type-two mounting hole (5018).

7. A low voltage electrical appliance load transfer switch according to claim 6, characterized in that: An annular groove (5011) is provided on the outer side wall of the shaft section of the shaft section (501) located in the mounting shell (3); two spring leaves (4) are symmetrically arranged in the mounting shell (3); the spring leaves (4) include a fixed end (401) and a movable end (402); the fixed end (401) is connected to the mounting seat by bolts; the movable end (402) is embedded in the groove (5011); when the spring leaves (4) are in a relaxed state, the vertical projections of the plurality of static contacts (10) do not intersect with the vertical projection of the moving contact (14).

8. A low voltage electrical appliance load transfer switch according to claim 7, characterized in that: The first-stage shaft (501), the second-stage shaft (502) and the third-stage shaft (503) are each provided with an airtight cavity (5019), and the plurality of airtight cavities (5019) are connected to the mounting grooves (5016) on both sides, the length of the airtight cavity (5019) is smaller than the length of the moving contact (14), and the width of the airtight cavity (5019) is smaller than the diameter of the second-type mounting hole (5018).

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