A contact structure for a vacuum interrupter

Abstract

The present application relates to a contact structure for a vacuum interrupter. The contact structure for a vacuum interrupter includes a coil, a conductive rod, and a contact piece. The coil is fixedly connected between the conductive rod and the contact piece. The contact piece has a disc structure and has a first surface facing the coil and a second surface facing away from the coil. The contact piece is provided with a first convex portion, and the first convex portion is provided at the edge of the second surface and extends circumferentially along the edge of the second surface. A second convex portion is provided on the side of the coil connected to the contact piece. The extending direction of the second convex portion corresponds to the extending direction of the first convex portion, and the position of the second convex portion corresponds to the position of the first convex portion. Through the above structure, the current flows into the upper contact structure through the upper conductive rod, completes the winding flow in the coil, and then flows into the contact piece through the second convex portion at the bottom of the coil, and directly realizes current conduction on the contact piece through the first convex portion. The heating degree of the middle part of the contact piece is reduced, the overcurrent path of the current in the contact piece is reduced, and the electrical life of the contact is improved.

Description

Technical Field

[0001] This application relates to the technical field of vacuum switches, and particularly to a contact structure for a vacuum interrupter. Background Art

[0002] A vacuum interrupter is the core component of a vacuum switch, responsible for cutting off the electric arc. The control and extinction of the electric arc are closely related to the control of the magnetic field by the contacts of the vacuum interrupter. Currently, the main magnetic field control technologies are longitudinal magnetic structures and transverse magnetic structures. As the core component for current conduction and arc control in a vacuum interrupter, the contact largely determines the performance of the interrupter. And the coil-type contact is a typical structure of the contact of the longitudinal magnetic structure. The current conduction loop and the opening loop of this contact are both the coil itself. The longer the flow path of the current in the contact structure, the stronger the magnetic field it can generate, and the stronger the opening ability of the contact.

[0003] As one of the key components of the contact structure, the contact piece undertakes multiple functions such as current conduction and opening. For the need of arc control, the outer side of the contact piece is often designed with a bevel transition between the bottom surface and the side surface, which results in a situation where the middle of the contact piece is in contact and the edges are suspended when the contact pairs are mated. When the contact pair is opened and conducting current, the current enters the edge of one contact piece through the excitation coil, flows from the edge to the middle inside the contact piece, then from the middle to the middle of the opposite contact piece (i.e., the other contact piece), and then from the middle of the opposite contact piece to the edge and enters the opposite excitation coil. During this process, the current flow path in the contact piece is relatively long, which is not conducive to improving the current-carrying capacity. Summary of the Invention

[0004] Based on this, in view of the problem that the current flow path through the contact piece is relatively long, it is necessary to provide a contact structure for a vacuum interrupter, characterized in that the contact structure for the vacuum interrupter includes a coil, a conductive rod, and a contact piece, and the coil is fixedly connected between the conductive rod and the contact piece;

[0005] The contact piece is a disc structure, having a first surface facing the coil and a second surface facing away from the coil;

[0006] The contact piece is provided with a first protrusion, and the first protrusion is provided at the edge of the second surface and extends circumferentially along the edge of the second surface; on the side of the coil connected to the contact piece, there is a second protrusion; the extending direction of the second protrusion corresponds to the extending direction of the first protrusion, and the position of the second protrusion corresponds to the position of the first protrusion.

[0007] The above-mentioned contact structure for a vacuum interrupter includes a coil, a conductive rod, and a contact piece. The coil is disposed between the conductive rod and the contact piece and is fixedly connected to the conductive rod and the contact piece. Among them, the contact piece has a disc structure with a first surface facing the coil and a second surface facing away from the coil. A first convex portion is locally thickened at a position near the edge of the second surface of the contact piece. The first convex portion extends along the circumferential direction of the edge of the second surface to form an annular shape on the outer periphery of the second surface, and the outer periphery of the annular shape is aligned with the edge of the second surface. A first convex portion is locally thickened at a position near the edge on the outside of the second surface, and a rounded corner is provided at the inner edge of the first convex portion to evenly distribute the electric field, and a rounded corner is provided at the edge of the second surface to evenly distribute the electric field. A second convex portion is provided on the side of the coil fixedly connected to the contact piece. The extending direction of the second convex portion is the same as that of the first convex portion, and the position of the second convex portion corresponds to that of the first convex portion, so that when the coil is fixedly connected to the first surface of the contact piece, the second convex portion corresponds to the first convex portion in position. Through the above structure, a first convex portion is provided on the second surface of the contact piece, so that when the contacts are mated, two corresponding contacts of the first convex portions can be formed, forming a structure with a middle suspended and the first convex portions at the edges in contact. And because the second convex portion on the coil fixedly connected to the first surface of the contact piece corresponds to the first convex portion in position, the current flows into the upper contact structure through the upper conductive rod, completes the flow around in the coil, and then flows into the contact piece through the second convex portion at the bottom of the coil. The current directly realizes current conduction through the first convex portion in the contact piece. This reduces the heating degree of the middle part of the contact piece. At the same time, the setting of the first convex portion reduces the overcurrent path of the current in the contact piece, further reduces the heating condition of the contact piece, enables the contact structure to withstand stronger ablation, and improves the electrical life of the contact.

[0008] In some embodiments, the width of the first convex portion is the same as the radial width of the second convex portion.

[0009] In some embodiments, the contact piece is provided with a plurality of truncation grooves, and the plurality of truncation grooves are evenly spaced along the circumferential direction of the contact piece; the first end of the truncation groove is located at the edge of the contact piece and is an open end, and the second end is closer to the center of the contact piece than the first end. The truncation groove penetrates along the thickness direction of the contact piece, so that the first convex portion is divided into a plurality of spaced-apart first arc-shaped convex segments along the circumferential direction of the contact piece.

[0010] In some embodiments, the extending direction of the truncation groove is along the radial direction of the contact piece, and the second ends of the plurality of truncation grooves are all spaced from the center of the contact piece.

[0011] In some embodiments, the length of the truncation groove is greater than the radial width of the first convex portion along the contact piece.

[0012] In some embodiments, the second raised portion includes a plurality of second arc-shaped raised segments arranged at intervals along the circumference of the coil, and the second arc-shaped raised segments correspond to the first arc-shaped raised segments one by one; the leading ends of the second arc-shaped raised segments are flush with the leading ends of the corresponding first arc-shaped raised segments, and the trailing ends of the second arc-shaped raised segments do not extend beyond the trailing ends of the first arc-shaped raised segments.

[0013] In some embodiments, the leading and trailing ends of the first arc-shaped raised segment are flush with the leading and trailing ends of the second arc-shaped raised segment.

[0014] In some embodiments, the number of the truncation grooves is 3 to 6.

[0015] In some embodiments, the first raised portion is annular, and the outer periphery of the first raised portion and the outer periphery of the contact piece are in arc transition.

[0016] In some embodiments, the thickness of the first raised portion is 2 mm to 5 mm. Description of the Drawings

[0017] Figure 1 Schematic diagram of the contact piece structure provided by an embodiment of the present application.

[0018] Figure 2 is Figure 1 Cross-sectional view taken along line A-A of

[0019] Figure 3 Schematic diagram of the contact structure provided by an embodiment of the present application.

[0020] Figure 4 Schematic diagram of the current flow through the contact structure provided by an embodiment of the present application.

[0021] Figure 5 Schematic diagram of the current overcurrent when the contact piece and the coil are aligned provided by an embodiment of the present application.

[0022] Reference Signs:

[0023] Contact piece 10; First surface 101; Second surface 102; First raised portion 103; First arc-shaped raised segment 1031; Truncation groove 104; First segment 1041; Second end 1042; Coil 20; Second raised portion 201; Second arc-shaped raised segment 2011; Conductive rod 30. Detailed Description of the Embodiments

[0024] To make the above objects, features, and advantages of the present application more apparent and understandable, the following provides a detailed description of the specific embodiments of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0025] In the description of the present application, it should be understood that if terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or positional relationship indicated by these terms is based on the orientation or positional relationship shown in the accompanying drawings. These are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application.

[0026] In addition, if terms such as "first" and "second" appear, these terms are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0027] In the present application, unless otherwise clearly specified and limited, if terms such as "install", "connect", "join", "fix", etc. appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0028] In this application, unless otherwise clearly defined and limited, if there is a description such as a first feature being "on" or "under" a second feature, its meaning can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature can mean that the first feature is directly above or obliquely above the second feature, or simply indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature can be that the first feature is directly below or obliquely below the second feature, or simply indicates that the horizontal height of the first feature is less than that of the second feature.

[0029] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or there can also be an intermediate element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time. If so, the terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used in this application are only for the purpose of illustration and do not represent the only implementation.

[0030] Referring to Figures 1 to 5 , Figure 1 FIG. shows a schematic diagram of the contact piece structure in an embodiment of the present application. A contact structure for a vacuum interrupter provided in an embodiment of the present application is characterized in that the contact structure for a vacuum interrupter includes a coil 20, a conductive rod 30 and a contact piece 10. The coil 20 is fixedly connected between the conductive rod 30 and the contact piece 10. The contact piece 10 is of a disc structure and has a first surface 101 facing the coil 20 and a second surface 102 facing away from the coil 20. The contact piece 10 is provided with a first protrusion 103, and the first protrusion 103 is provided at the edge of the second surface 102 and extends circumferentially along the edge of the second surface 102. A second protrusion 201 is provided on the side of the coil 20 connected to the contact piece 10. The extending direction of the second protrusion 201 corresponds to the extending direction of the first protrusion 103, and the position of the second protrusion 201 corresponds to the position of the first protrusion 103.

[0031] As Figure 1 and Figure 2As shown in the figure, the contact structure for a vacuum interrupter is composed of three parts: a contact piece 10, a coil 20, and a conducting rod 30 on one side of the contact structure. The parts are connected by brazing, and the contact structures on both sides of the contact pair are the same. The coil 20 is arranged between the conducting rod 30 and the contact piece 10 and is fixedly connected to the conducting rod 30 and the contact piece 10. Among them, the contact piece 10 has a disc structure with a first surface 101 facing the coil 20 and a second surface 102 facing away from the coil 20. A first raised portion 103 is formed by locally thickening a part of the second surface 102 of the contact piece 10 near the edge. The first raised portion 103 extends along the circumferential direction of the edge of the second surface 102 to form a ring on the outer periphery of the second surface 102, and the outer periphery of the ring is aligned with the edge of the second surface 102. A first raised portion 103 is formed by locally thickening the part near the edge on the outside of the second surface 102, and a rounded corner is provided at the inner edge of the first raised portion 103 to uniform the electric field, and a rounded corner is provided at the edge of the second surface to uniform the electric field. A second raised portion 201 is provided on the side where the coil 20 is fixedly connected to the contact piece 10. The extending direction of the second raised portion 201 is the same as that of the first raised portion 103, and the position of the second raised portion 201 corresponds to that of the first raised portion 103, so that when the coil 20 is fixedly connected to the first surface 101 of the contact piece 10, the second raised portion 201 corresponds to the first raised portion 103 in position. Through the above structure, the first raised portion 103 is provided on the second surface 102 of the contact piece 10, so that when the contact pair is matched, two corresponding contacts of the first raised portions 103 can be formed, forming a structure with a middle suspended and the first raised portions 103 at the edge in contact. And because the second raised portion 201 on the coil 20 fixedly connected to the first surface 101 of the contact piece 10 corresponds to the first raised portion 103 in position, the current flows into the upper contact structure through the upper conducting rod 30, completes the flow around in the coil 20, and then flows into the contact piece 10 through the second raised portion 201 at the bottom of the coil 20, and the current directly realizes current conduction through the first raised portion 103 on the contact piece 10. This reduces the heating degree of the middle part of the contact piece 10. At the same time, the setting of the first raised portion 103 reduces the overcurrent path of the current in the contact piece 10, further reduces the heating condition of the contact piece 10, enables the contact structure to withstand stronger ablation, and improves the electrical life of the contact.

[0032] In some embodiments, the width of the first raised portion 103 is the same as the radial width of the second raised portion 201. The first raised portion 103 is arranged at the outer peripheral edge of the second surface 102 of the contact piece 10 to form a ring, and the position of the second raised portion 201 on the coil 20 corresponds to the position of the first raised portion 103, so that after the current completes the flow around in the coil 20, it flows into the contact piece 10 through the second raised portion 201 of the coil 20 and directly realizes current conduction through the first raised portion 103. Setting the width of the first raised portion 103 to be the same as the radial width of the second raised portion 201, that is, the ring width of the first raised portion 103 is the same as the ring width of the second raised portion 201, further ensures the overcurrent efficiency.

[0033] As shown Figure 1 In some embodiments, as shown, the contact piece 10 is provided with a plurality of truncation grooves 104, and the plurality of truncation grooves 104 are evenly spaced along the circumferential direction of the contact piece 10; the first end 1041 of the truncation groove 104 is located at the edge of the contact piece 10 and is an open end, and the second end 1042 is closer to the center of the contact piece 10 relative to the first end 1041. The truncation groove 104 penetrates along the thickness direction of the contact piece 10, so that the first protrusion 103 is divided into a plurality of first arc-shaped protrusion segments 1031 that are spaced apart along the circumferential direction of the contact piece 10.

[0034] Truncation grooves 104 are provided on the contact piece 10 and are evenly spaced along the circumferential direction of the contact piece 10. The first end 1041 of the truncation groove 104 is provided at the edge of the contact piece 10 and has an opening as an open end, and the other end is close to the central part of the contact piece 10 to divide the contact piece 10 into multiple parts. The truncation groove 104 penetrates along the thickness direction of the contact piece 10, so that the first protrusion 103 is divided into a plurality of first arc-shaped protrusion segments 1031 that are spaced apart along the circumferential direction of the contact piece 10. The arrangement of the plurality of truncation grooves 104 can realize truncating the current-carrying path of the eddy current, improve the problem that the heat generation of the contact piece 10 increases significantly due to the axial flow of the eddy current along the contact piece 10, and stimulate the induced magnetic field to offset and weaken the original magnetic field, thereby leading to the problem of the decline of the contact arc control ability. By opening truncation grooves 104 on the contact piece 10 to truncate the eddy current, the negative impact of the eddy current on breaking and current-carrying is reduced. By adding the first protrusion 103 structure on the contact piece 10, cooperating with the truncation groove 104 and combining with the corresponding assembly method, the current path is changed, the length of the current-carrying path of the coil 20 type contact is reduced, and the current-carrying performance is optimized without affecting its breaking performance.

[0035] As shown Figure 1 In some embodiments, as shown, the extending direction of the truncation groove 104 is along the radial direction of the contact piece 10, and the second ends 1042 of the plurality of truncation grooves 104 are all spaced apart from the center of the contact piece 10.

[0036] The truncation groove 104 is grooved radially from the edge of the contact piece 10 to the central part of the contact piece 10, that is, the truncation groove 104 is grooved radially from the outside of the contact piece 10 to the central part of the contact piece 10 to truncate the current-carrying path of the eddy current, and the second ends 1042 of the plurality of truncation grooves 104 are all spaced apart from the center of the contact piece 10, and the plurality of truncation grooves 104 do not intersect at the center of the contact piece 10, further improving the problem of heat generation at the central part of the contact piece 10.

[0037] In some embodiments, the length of the truncation groove 104 is greater than the radial width of the first convex portion 103 along the contact piece 10. Since the first convex portion 103 is annularly arranged on the outer side of the second surface 102 of the contact piece 10, the length of the truncation groove 104 is set to be greater than the radial width of the first convex portion 103 along the contact piece 10, that is, greater than the ring width of the first convex portion 103, so that the truncation groove 104 can penetrate the contact piece 10 along the thickness direction of the contact piece 10 to truncate the eddy current and thus suppress the eddy current. Improving the eddy current will cause a significant increase in the heat generation of the contact piece 10 and excite an induced magnetic field to offset and weaken the original magnetic field, thereby causing a decrease in the contact arc control ability. And since the first convex portion 103 is arranged at the edge of the contact piece 10, the current only flows through the first convex portion 103, reducing the heat generation degree of the middle part of the contact piece 10.

[0038] As Figure 4 and Figure 5 shown, in some embodiments, the second convex portion 201 includes a plurality of second arc-shaped convex segments 2011 arranged at intervals along the circumferential direction of the coil 20, and the second arc-shaped convex segments 2011 correspond to the first arc-shaped convex segments 1031 one by one; the leading end of the second arc-shaped convex segment 2011 is flush with the leading end of the corresponding first arc-shaped convex segment 1031, and the trailing end of the second arc-shaped convex segment 2011 does not extend beyond the trailing end of the first arc-shaped convex segment 1031.

[0039] The truncation groove 104 divides the first convex portion 103 into a plurality of first arc-shaped convex segments 1031 arranged at intervals along the circumferential direction of the contact piece 10. Since the second convex segments correspond to the first convex segments in position, the second convex segments on the coil 20 also need to be arranged as a plurality of second arc-shaped convex segments 2011 at intervals along the circumferential direction of the coil 20. When the coil 20 is fixedly connected to the truncation groove 104, the positions of the second arc-shaped convex segments 2011 correspond to the positions of the first arc-shaped convex segments 1031 one by one, and the second convex portion 201 on the coil 20 cannot span across the truncation groove 104 to prevent the arc from ablating the second convex portion 201. Each second arc-shaped convex segment on the coil has a leading end and a trailing end and corresponds to the leading end and the trailing end of the first arc-shaped convex segment. The leading end of the second arc-shaped convex segment 2011 on the coil 20 is set to be flush with the leading end of the corresponding first arc-shaped convex segment 1031, so that when the current flows through the leading end of the second arc-shaped convex segment 2011 of the coil 20 to the first surface 101 of the contact piece 10, it can directly flow through the leading end of the first arc-shaped convex segment 1031 flush with it into the contact piece 10, and then directly flow through the first arc-shaped convex segment 1031 on the second surface 102 to the leading end of the first arc-shaped convex segment 1031 on the second surface 102 of the opposite contact piece 10 in contact with it, and flow to the second arc-shaped convex segment 2011 of the opposite coil 20. By setting the leading end of the second arc-shaped convex segment 2011 to be flush with the leading end of the first arc-shaped convex segment 1031, the current can be constrained to flow only along a determined direction.

[0040] In some embodiments, the leading end and the trailing end of the first arc-shaped convex segment 1031 are flush with the leading end and the trailing end of the second arc-shaped convex segment 2011 respectively.

[0041] When the leading end of the second arc-shaped convex segment 2011 is flush with the leading end of the first arc-shaped convex segment 1031, the trailing end of the second arc-shaped convex segment 2011 is also flush with the trailing end of the first arc-shaped convex segment 1031. So that when the current flows from the leading end of the second arc-shaped convex segment 2011 of the coil 20 to the first surface 101 of the contact piece 10, it can directly flow through the leading end of the first arc-shaped convex segment 1031 that is flush with it and enter the contact piece 10, and then directly flow through the first arc-shaped convex segment 1031 on the second surface 102 to the leading end of the first arc-shaped convex segment 1031 on the second surface 102 of the opposite contact piece 10 that it contacts, flow into the contact piece 10 and flow from the leading end to the trailing end of the first arc-shaped convex segment 1031, and flow to the second arc-shaped convex segment 2011 of the opposite coil 20, thereby realizing the constraint that the current can only flow along a determined direction.

[0042] In some embodiments, the number of the truncation grooves 104 is 3 to 6. The truncation grooves 104 are provided in the number of 3 to 6 so as to divide the first arc-shaped convex segment 1031 into 3 to 6 parts, truncate the first convex portion 103, so that the eddy current can only flow through the first arc-shaped convex segment 1031, truncate the eddy current to suppress the eddy current, and reduce the negative impact of the eddy current on the opening and current flow, and further improve the problem that the heat generation of the contact piece 10 caused by the eddy current increases significantly and the induced magnetic field is excited to cancel and weaken the original magnetic field, thereby causing the contact arc control ability to decline.

[0043] As Figures 1 to 3 shown, in some embodiments, the first convex portion 103 is circular ring-shaped, and the outer periphery of the first convex portion 103 and the outer periphery of the contact piece 10 are in arc transition.

[0044] One side of the contact structure is composed of three parts: a contact piece 10, a coil 20, and a conductive rod 30. The parts are connected by brazing, and the contact structures on both sides of the contact pair are the same. The first convex portion 103 is set as circular ring-shaped, so that the contact structures on both sides between the contact pairs are correspondingly installed, that is, the truncation groove 104 is opposite to the truncation groove 104, the coil 20 and the opposite coil 20 are in corresponding positions. When the cooperating contact pieces 10 contact through the first convex portion 103 on the second surface 102 and the first convex portion 103 of the opposite contact piece 10, a structure with a middle suspended part and an edge in circular ring-shaped contact is formed, so as to directly realize the current flow through the first convex portion 103. The outer periphery of the first convex portion, that is, the outer periphery of the circular ring-shaped part on the second surface and the edge part are set in arc transition.

[0045] In some embodiments, the thickness of the first convex portion 103 is 2 mm to 5 mm. By setting the thickness of the first convex portion 103 to 2 mm to 5 mm, that is, the thickness of the edge of the contact piece 10 is 2 mm to 5 mm more than the thickness in the middle of the contact piece 10, when the two-side contact structures between the contact pairs are correspondingly installed, a structure in which the middle of the two-side contact pieces 10 is suspended and the edges are in contact can be formed. The thickened first convex portion 103 can withstand stronger ablation, improving the electrical life of the contact. This enables the current to only flow through the first convex portion 103, reducing the heat generation degree in the middle part of the contact piece 10. At the same time, the presence of the convex platform reduces the overcurrent path of the current in the contact piece 10, further reducing the heat generation of the contact piece 10.

[0046] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0047] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A contact structure for a vacuum interrupter, characterized in that, the contact structure for the vacuum interrupter includes a coil, a conductive rod, and a contact piece, and the coil is fixedly connected between the conductive rod and the contact piece; the contact piece is a disc structure, having a first surface facing the coil and a second surface facing away from the coil; the contact piece is provided with a first protrusion, and the first protrusion is arranged at the edge of the second surface and extends circumferentially along the edge of the second surface; a second protrusion is provided on the side of the coil connected to the contact piece; the extending direction of the second protrusion corresponds to the extending direction of the first protrusion, and the position of the second protrusion corresponds to the position of the first protrusion; the width of the first protrusion is the same as the radial width of the second protrusion; the contact piece is provided with a plurality of truncation grooves, and the plurality of truncation grooves are evenly spaced along the circumferential direction of the contact piece; the first end of the truncation groove is located at the edge of the contact piece and is an open end, the second end of the truncation groove is closer to the center of the contact piece than the first end, and the truncation groove penetrates along the thickness direction of the contact piece, so that the first protrusion is divided into a plurality of spaced-apart first arc-shaped protrusion segments along the circumferential direction of the contact piece.

2. The contact structure for a vacuum interrupter according to claim 1, characterized in that, the extending direction of the truncation groove is along the radial direction of the contact piece, and the second ends of the plurality of truncation grooves are all spaced from the center of the contact piece.

3. The contact structure for a vacuum interrupter according to claim 2, characterized in that, the length of the truncation groove is greater than the radial width of the first protrusion along the contact piece.

4. The contact structure for a vacuum interrupter according to claim 1, characterized in that, the second protrusion includes a plurality of second arc-shaped protrusion segments spaced along the circumferential direction of the coil, and the second arc-shaped protrusion segments correspond to the first arc-shaped protrusion segments one by one; the first end of the second arc-shaped protrusion segment is flush with the first end of the corresponding first arc-shaped protrusion segment, and the end of the second arc-shaped protrusion segment does not extend beyond the end of the first arc-shaped protrusion segment.

5. The contact structure for a vacuum interrupter according to claim 4, characterized in that, the first end and the end of the first arc-shaped protrusion segment are both flush with the first end and the end of the second arc-shaped protrusion segment.

6. The contact structure for a vacuum interrupter according to claim 1, characterized in that, the number of the truncation grooves is 3 to 6.

7. The contact structure for a vacuum interrupter according to claim 1, characterized in that, the first protrusion is an annular shape, and the outer periphery of the first protrusion and the outer periphery of the contact piece are in arc transition.

8. The contact structure for a vacuum interrupter according to claim 1, characterized in that, the thickness of the first protrusion is 2 mm to 5 mm.

Images