Contact assembly of breaking device and dual-power change-over switch

Abstract

The embodiment of the utility model provides a contact assembly of a breaking device and a dual-power change-over switch. The contact assembly comprises an arc extinguishing assembly which comprises an arc extinguishing grid sheet group located in an arc extinguishing chamber, and a first arc striking sheet and a second arc striking sheet which are located at the two ends of the arc extinguishing chamber; the static contact is connected with the wire inlet terminal through a first litzendraht wire, the static contact comprises a U-shaped structure, the U-shaped structure comprises a first section and a second section which are opposite to each other, the first section is pivoted with the first pivot so that the static contact can rotate between a first closing position and a first opening position, and a static contact is arranged on the second section; when the static contact is located at a first opening position, the free end of the second section is close to the first arc striking sheet; and the contact pressure piece elastically abuts against the static contact so as to apply a force for moving towards the first opening position to the static contact.

Description

TECHNICAL FIELD

[0001] Embodiments of the present disclosure generally relate to the field of electrical equipment, and in particular, to a contact assembly of a disconnector and a double power transfer switch. BACKGROUND

[0002] In some electrical equipment, to avoid power failure caused by the electrical equipment, two independent power supplies, i.e., a normal power supply and a backup power supply, are usually configured for the electrical equipment. The normal power supply and the backup power supply selectively supply power to the electrical equipment through a double power transfer switch (also referred to as a double power automatic transfer switch), thereby providing continuous power supply for important electrical equipment.

[0003] The double power transfer switch includes two contact assemblies, each of which includes a static contact, a moving contact mounted on a moving contact support, and an arc extinguishing assembly. The moving contact support can rotate between an open position and a closed position. When the moving contact support is in the open position, the moving contact on the moving contact support is separated from the static contact, and at this time the contact assembly is in an open state. When the moving contact support is in the closed position, the moving contact on the moving contact support abuts against the static contact, and at this time the contact assembly is in a closed state. When one of the two contact assemblies is in the closed state, the other is in the open state, so that one of the normal power supply and the backup power supply supplies power to the electrical equipment. The arc extinguishing assembly is used to extinguish the arc generated when the moving contact and the static contact are separated. SUMMARY

[0004] In a first aspect of the present disclosure, a contact assembly of a disconnector for a double power transfer switch is provided, comprising: an arc extinguishing assembly including an arc extinguishing grid set in an arc extinguishing chamber and a first arc striking sheet and a second arc striking sheet at two ends of the arc extinguishing chamber; a static contact connected with a line terminal through a first braid, the static contact including a U-shaped structure, the U-shaped structure including a first segment and a second segment opposite to each other, wherein the first segment is pivotally connected with a first pivot to enable the static contact to rotate between a first closed position and a first open position, and the second segment is provided with a static contact point; when the static contact is in the first open position, a free end of the second segment is close to the first arc striking sheet; and a contact pressure piece elastically abutting against the static contact to apply a force to the static contact to move towards the first open position.

[0005] In some embodiments, the contact assembly further comprises a shielding piece arranged between the first segment and the second segment.

[0006] In some embodiments, the static contact further comprises a third segment, the first segment is pivotally connected with the first pivot through the third segment, and the third segment extends obliquely from the first segment towards the first arc striking sheet.

[0007] In some embodiments, the stationary contact further comprises a fourth segment extending from the third segment away from the first segment, and the first pivot is located at a junction of the third segment and the fourth segment, and the first braid is connected to the fourth segment.

[0008] In some embodiments, the contact assembly further comprises: a moving contact provided with a moving contact point; and a moving contact holder fixedly connected to the moving contact and connected to the load terminal through a second braid, and wherein the moving contact holder is sleeved on the second pivot so that the moving contact can rotate between the second closed position and the second open position, and when the moving contact is in the second closed position, the moving contact point abuts against the stationary contact point to keep the stationary contact in the first closed position.

[0009] In some embodiments, the contact assembly further comprises a gas production sheet located on both sides of the rotation track of the moving contact.

[0010] In some embodiments, the second segment comprises a main body portion, the stationary contact point protrudes from a middle portion of the main body portion, and an arc striking protrusion is further provided on the main body portion, the arc striking protrusion extends from a side wall of the stationary contact point to a free end of the main body portion.

[0011] In some embodiments, the contact pressure piece comprises an elastic piece, the elastic piece abuts against the first segment.

[0012] In some embodiments, the contact pressure piece further comprises: a fixed plate provided on a housing of the breaking device; and a support piece connected to the fixed plate, the elastic piece is sleeved on the support piece.

[0013] In a second aspect of the present disclosure, a double power transfer switch is provided, the double power transfer switch comprises a breaking device, the breaking device comprises two contact assemblies of the breaking device according to the first aspect of the present disclosure.

[0014] In embodiments according to the present disclosure, when the stationary contact and the moving contact are separated, the stationary contact can rotate around the first pivot to the first open position. At the first open position, the free end of the second segment of the stationary contact is close to the first arc striking sheet, and the current flowing in the second segment generates a magnetic field around the second segment. This magnetic field generates a magnetic blowing force on the arc between the stationary contact and the moving contact to move into the arc extinguishing chamber, thereby helping to quickly extinguish the arc and helping to improve the on-off breaking performance of the contact assembly.

[0015] It should be understood that the content described in this content part is not intended to limit the key features or important features of the embodiments of the present disclosure, nor is it used to limit the scope of the present disclosure. Other features of the present disclosure will become apparent through the following description. BRIEF DESCRIPTION OF DRAWINGS

[0016] The above and other features, advantages, and aspects of embodiments of the present disclosure will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which:

[0017] Figure 1 An internal structure schematic diagram of a disconnection device of a double power transfer switch according to an embodiment of the present disclosure is shown, the disconnection device comprising two contact assemblies according to an embodiment of the present disclosure;

[0018] Figure 2 An internal structure schematic diagram of a disconnection device of a double power transfer switch according to an embodiment of the present disclosure is shown, the disconnection device comprising two contact assemblies according to an embodiment of the present disclosure; Figure 1 A perspective structure schematic diagram of the disconnection device shown is shown; and

[0019] Figures 3 to 6 An internal structure schematic diagram of a disconnection device of a double power transfer switch according to an embodiment of the present disclosure is shown, the disconnection device comprising two contact assemblies according to an embodiment of the present disclosure; Figure 1 The opening process of one of the two contact assemblies in the double power transfer switch is shown. DETAILED DESCRIPTION

[0020] Preferred embodiments of the present disclosure will be described herein below with reference to the accompanying drawings. Although preferred embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure is more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0021] The term "comprising" and variations thereof as used herein are intended to cover a non-exclusive inclusion, i.e., "including, but not limited to". Unless specifically stated, the term "or" means "and / or". The term "based on" means "based, at least in part, on". The terms "one example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. can refer to different or same objects.

[0022] Embodiments of the present disclosure provide a contact assembly of a disconnection device and a double power transfer switch. The double power transfer switch configured with the contact assembly has good on-disconnection performance, and also has good short-time withstand current performance. In the following, the contact assembly of the disconnection device will be described in combination with Figures 1 to 6 The principles of the present disclosure are described.

[0023] Figure 1 An internal structure schematic diagram of a disconnection device of a double power transfer switch according to an embodiment of the present disclosure is shown, the disconnection device comprising two contact assemblies 100 according to an embodiment of the present disclosure. Figure 2 An internal structure schematic diagram of a disconnection device of a double power transfer switch according to an embodiment of the present disclosure is shown, the disconnection device comprising two contact assemblies according to an embodiment of the present disclosure; Figure 1 A perspective structure schematic diagram of the disconnection device shown is shown. Figures 3 to 6 An internal structure schematic diagram of a disconnection device of a double power transfer switch according to an embodiment of the present disclosure is shown, the disconnection device comprising two contact assemblies according to an embodiment of the present disclosure; Figure 1the opening and closing process of one of the two contact assemblies 100 in the double-pole double-throw switch.

[0024] The breaking device for the double-pole double-throw switch in the embodiments of the present disclosure comprises a housing 80 and two contact assemblies 100 arranged on the housing 80, and the two contact assemblies 100 are substantially identical in structure. The structure of the contact assembly 100 will be described below mainly by taking one contact assembly 100 as an example.

[0025] Referring to Figure 1 and Figure 2 , the contact assembly 100 comprises an arc extinguishing assembly 10, a stationary contact 20, a contact pressure piece 40, a shielding piece 50, a movable contact 61 and a movable contact bracket 62.

[0026] An arc chamber 801 is formed in the inner cavity of the housing 80 of the breaking device, and the arc extinguishing assembly 10 is arranged in the arc chamber 801. The arc extinguishing assembly 10 comprises an arc extinguishing grid set 13 in the arc chamber 801 and a first arc striking piece 11 and a second arc striking piece 12 at both ends of the arc chamber 801.

[0027] The line terminal 91 of the breaking device extends from the outside of the housing 80 into the inner cavity of the housing 80, and the line terminal 91 is used to be connected with the corresponding normal power supply or standby power supply.

[0028] The stationary contact 20 is arranged in the inner cavity of the housing 80 and located between the first arc striking piece 11 and the line terminal 91. The stationary contact 20 is connected with the line terminal 91 through the first braid 31. The stationary contact 20 is sleeved on the first pivot 201, so as to be able to rotate around the first pivot 201 between a first closing position and a first opening position. The included angle between the first closing position and the first opening position is small. Any suitable angle limiting mechanism can be arranged in the housing 80 to limit the rotation range of the stationary contact 20.

[0029] In some embodiments, the stationary contact 20 is substantially in a bent shape. Specifically, the stationary contact 20 can comprise a U-shaped structure, a third segment 23 and a fourth segment 24. In some embodiments, the opening of the U-shaped structure faces the first pivot 201, and the arc extinguishing assembly 10 is located between the first pivot 201 and the U-shaped structure. The U-shaped structure can comprise a first segment 21 and a second segment 22 opposite to each other. The second segment 22 is located between the first segment 21 and the movable contact 61, and a stationary contact point 221 is arranged on the second segment 22. The third segment 23 extends obliquely from the first segment 21 towards the first arc striking piece 11, and one end of the third segment 23 away from the first segment 21 is pivoted to the first pivot 201, so that the first segment 21 is pivoted to the first pivot 201 through the third segment 23. The fourth segment 24 extends from the end of the third segment 23 away from the first segment 21, that is, the first pivot 201 is located at the joint of the third segment 23 and the fourth segment 24. The first braid 31 is connected with the fourth segment 24.

[0030] Of course, the implementation of the stationary contact 20 is not limited to the examples described above. For example, in some alternative embodiments, the third segment 23 extends in the same direction as the first segment 21. In some alternative embodiments, the fourth segment 24 may be omitted, and the first braided wire 31 may be directly connected to the third segment 23.

[0031] The contact pressure member 40 is located within the inner cavity of the housing 80. The contact pressure member 40 elastically abuts against the stationary contact 20 to apply an elastic force to the stationary contact 20, causing it to move towards the first open position. In some embodiments, the contact pressure member 40 includes, for example, an elastic member 41, a fixing plate 42, and a support member 43. The fixing plate 42 may be disposed on the housing 80 of the disconnecting device. The support member 43 may be, for example, a screw, and is connected to the fixing plate 42, for example, by screwing. The elastic member 41 may be, for example, a spring, and is sleeved on the support member 43. The elastic member 41 abuts against, for example, the first segment 21 of the stationary contact 20. Of course, the implementation of the contact pressure member 40 is not limited to this; it only needs to be able to apply an elastic force to the stationary contact 20, causing it to move towards the first open position.

[0032] The moving contact 61 and the moving contact support 62 are located in the inner cavity of the housing 80. The moving contact 61 is fixedly connected to the moving contact support 62. The moving contact 61 is provided with a moving contact 611. The moving contact support 62 is connected to the load terminal 92 through the second braided wire 32. The load terminal is connected to the electrical equipment.

[0033] It should be noted that, in some embodiments, the moving contact supports 62 of the two contact assemblies 100 are connected to the same load terminal 92 via corresponding second braided wires 32. In some alternative embodiments, the moving contact supports 62 of the two contact assemblies 100 are connected to two load terminals 92 via corresponding second braided wires 32, and these two load terminals 92 can be stacked together and electrically connected to each other.

[0034] The moving contact bracket 62 is sleeved on the second pivot 601, allowing the moving contact 61 to rotate between the second closed position and the second open position. The moving contact 61 can be held in the second closed position and the second open position by an operating mechanism (not shown in the figure) connected to the moving contact bracket 62.

[0035] exist Figure 1Of the two contact assemblies 100 shown, the upper contact assembly 100 is in the open state, and the lower contact assembly 100 is in the closed state. In the upper contact assembly 100, the moving contact 61 is in the second open position, and the stationary contact 20 is held in the first open position under the pressure of the contact pressure member 40. The moving contact 61 and the stationary contact 20 are far apart from each other, and there is an open circuit between the incoming terminal 91 and the load terminal 92. In the lower contact assembly 100, the moving contact 61 is in the second closed position, and the stationary contact 20 is pressed to the first closed position by the passive contact 61. The elastic member 41 is compressed, and the moving contact 611 of the moving contact 61 and the stationary contact 221 of the stationary contact 20 abut against each other. There is a closed circuit between the incoming terminal 91 and the load terminal 92.

[0036] The following is combined Figures 3 to 6 The tripping process of contact assembly 100 will be illustrated using one contact assembly 100 as an example. For simplicity of view, Figures 4 to 6 The second braided wire 32 and the load terminal 92 are not shown in the diagram.

[0037] See Figure 3 When the contact assembly 100 is in the closed state, the moving contact 61 is held in the second closed position by an operating mechanism connected to the moving contact bracket 62. The stationary contact 20 is held in the first closed position by the contact between the moving contact 611 and the stationary contact 221. The free end of the second segment 22 of the stationary contact 20 is offset from the first arc-starting plate 11. The elastic element 41 of the contact pressure element 40 is compressed. The current flowing from the mains power supply or backup power supply sequentially passes through the incoming terminal 91, the first braided wire 31, the stationary contact 20, the moving contact 61, the second braided wire 32, and the load terminal 92, flowing into the electrical equipment connected to the load terminal 92.

[0038] Both the stationary contact 20 and the moving contact 61 will be affected Figure 3 The electric force is indicated by the arrow N. When an overcurrent occurs in the circuit, although the electric force increases, the moving contact 61, fixed on the moving contact bracket 62, remains in the second closed position under the action of the operating mechanism, instead of immediately rotating in direction S2 around the second pivot 601. Simultaneously, the stationary contact 20, under the action of the contact pressure member 40 and the electric force, tends to rotate in direction S1 around the first pivot 201. Therefore, the stationary contact 221 of the stationary contact 20 and the moving contact 611 of the moving contact 61 are tightly fitted, keeping the contact assembly 100 in the closed state. Thus, the contact assembly 100 has high short-time withstand current performance. In this way, even if an overcurrent occurs due to a circuit fault, the dual-power transfer switch can still effectively carry the current. After the faulty circuit is disconnected by the corresponding circuit breaker, the dual-power transfer switch can effectively switch the power supply. Because the contact assembly 100 has high short-time withstand current performance, it can prevent the contact assembly 100 from being damaged by overcurrent, and can effectively improve the availability time of the continuous power supply.

[0039] Referring to Figure 4 When switching the power supply, the operating mechanism controls the movable contact 61 to rotate around the second pivot 601 in the direction S2 through the movable contact support 62. The stationary contact 20 is pushed by the contact pressure piece 40 to rotate around the first pivot 201 in the direction S1 to the first open position. Figure 4 The stationary contact 20 in the first open position. When the stationary contact 20 moves to the first open position, the stationary contact 20 no longer continues to rotate in the direction S1, and the movable contact 611 of the movable contact 61 begins to separate from the stationary contact 221 of the stationary contact 20.

[0040] When the stationary contact 20 is in the first open position, the free end of the second section 22 of the stationary contact 20 is close to the first arc guiding piece 11, and the gap between the free end of the second section 22 and the first arc guiding piece 11 is relatively small.

[0041] Referring to Figure 4 and Figure 5 When the movable contact 611 of the movable contact 61 and the stationary contact 221 of the stationary contact 20 are separated, an arc 15 is generated between the movable contact 61 and the stationary contact 20. When the movable contact 61 rotates in the direction S2, the arc 15 moves from the stationary contact 20 to the first arc guiding piece 11. The current flowing from the incoming terminal 91, indicated by the dashed arrow C, flows to the second section 22, and the current flowing in the second section 22 generates a magnetic field around the second section 22, which generates a magnetic blowing force indicated by the arrow F on the arc 15, so that the arc 15 can quickly enter the arc extinguishing chamber 801 to be extinguished. Thus, the on-off performance and electrical operating performance of the contact assembly 100 are improved.

[0042] Referring to Figure 1 , Figure 2 and Figure 5 In some embodiments, the second section 22 includes a main body part 222, and the free end of the second section 22 corresponds to the free end of the main body part 222. The stationary contact 221 protrudes from the middle part of the main body part 222. An arc guiding protrusion 223 is further provided on the main body part 222, which extends from the side wall of the stationary contact 221 to the free end of the main body part 222. When the stationary contact 20 is in the first open position, the surface of the first arc guiding piece 11 facing the arc extinguishing grid piece group 13 is close to the surface of the arc guiding protrusion 223, which is more conducive to the arc moving from the stationary contact 221 of the stationary contact 20 to the first arc guiding piece 11 through the arc guiding protrusion 223, thereby avoiding excessive ablation of the stationary contact 221 by the arc.

[0043] In some embodiments, the contact assembly 100 can further include a shield 50 disposed between the first segment 21 and the second segment 22. The shield 50 is configured to shield the magnetic field generated by the current flowing through the first segment 21 from adversely affecting the movement of the arc 15 towards the arc chamber 801.

[0044] Referring to Figure 6 When the static contact 20 and the moving contact 61 are separated, the moving contact 61 is rotated to the second open position and is held in the second open position by an operating mechanism connected to the moving contact holder 62. At this time, the moving contact 61 is close to the second arc striking plate 12, and the arc 15 can move towards the arc chamber 801 through the second arc striking plate 12 to be cut by the arc cutting blade group 13.

[0045] In some embodiments, the contact assembly 100 can further include a gas generating plate (not shown in the figure) located on both sides of the rotation track of the moving contact 61. When the moving contact 61 and the static contact 20 are separated, the gas generating plate is burned by the arc 15 to generate a large amount of gas, which causes the pressure in the arc chamber 801 to rise and form a pressure difference with the outside of the arc chamber 801. The gas flows from the arc chamber 801 to the outside of the arc chamber 801, forming a gas blowing effect on the arc 15, further helping the arc 15 to quickly enter the arc chamber 801 to be extinguished. This can further improve the on-off performance of the contact assembly 100.

[0046] According to an embodiment of the present disclosure, a double power transfer switch is also provided, which includes a breaking device including two contact assemblies 100 according to an embodiment of the present disclosure.

[0047] In the contact assembly 100 according to an embodiment of the present disclosure, when the static contact 20 and the moving contact 61 are separated, the static contact 20 can be rotated about the first pivot 201 to the first open position. At the first open position, the free end of the second segment 22 of the static contact 20 is close to the first arc striking plate 11, and the current flowing in the second segment 22 generates a magnetic field around the second segment 22. This magnetic field generates a magnetic blowing force on the arc 15 between the static contact 20 and the moving contact 61 to move into the arc chamber 801, thereby helping to quickly extinguish the arc 15 and improve the on-off performance of the contact assembly 100.

[0048] In addition, the moving contact 61 and the moving contact holder 62 are fixed together, and when the moving contact point 611 of the moving contact 61 and the static contact point 221 of the static contact 20 abut, the moving contact 61 can be held in the first closed position by the operating mechanism connected to the moving contact holder 62. In this way, when an overcurrent occurs in the circuit, the moving contact point 611 of the moving contact 61 and the static contact point 221 of the static contact 20 abut against each other rather than immediately separate, thus making the contact assembly 100 have a higher short-time withstand current performance.

[0049] It can be understood that the double power transfer switch with the contact assembly 100 has good electrical operation performance, on-off breaking performance and short-time withstand current performance.

[0050] Embodiments of the present disclosure have been described above, the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles, practical applications, or technical improvements in the market of the embodiments, or to enable other ordinary skilled in the art to understand the embodiments disclosed herein.

Claims

1. A contact assembly (100) of a disconnector device for a double-pole changeover switch, characterized in that Comprising: an arc extinguishing assembly (10) comprising an arc extinguishing vane group (13) located in an arc extinguishing chamber (801) and a first arc striking vane (11) and a second arc striking vane (12) located at both ends of the arc extinguishing chamber (801); a stationary contact (20) connected with an incoming line terminal (91) through a first braid wire (31), the stationary contact (20) comprising a U-shaped structure, the U-shaped structure comprising a first segment (21) and a second segment (22) opposite to each other, wherein the first segment (21) is pivoted with a first pivot (201) to enable the stationary contact (20) to rotate between a first closed position and a first open position, and the second segment (22) is provided with a stationary contact point (221); when the stationary contact (20) is in the first open position, a free end of the second segment (22) is close to the first arc striking vane (11); and a contact pressure piece (40) elastically abutting against the stationary contact (20) to apply a force to the stationary contact (20) to move towards the first open position.

2. The contact assembly (100) of claim 1, characterized in that Further comprising a shielding piece (50) arranged between the first segment (21) and the second segment (22).

3. The contact assembly (100) according to claim 1 or 2, characterized in that The stationary contact (20) further comprises a third segment (23), the first segment (21) is pivoted with the first pivot (201) through the third segment (23), and the third segment (23) extends obliquely from the first segment (21) towards the first arc striking vane (11).

4. The contact assembly (100) according to claim 3, wherein the stationary contact further comprises a fourth segment (24) extending from an end of the third segment (23) away from the first segment (21), and the first pivot (201) is located at a joint of the third segment (23) and the fourth segment (24), and the first braid wire (31) is connected with the fourth segment (24).

5. The contact assembly (100) of claim 1 or 2, characterized in that, Further comprising: a movable contact (61) provided with a movable contact point (611); and a movable contact support (62) fixedly connected with the movable contact (61) and connected with a load terminal (92) through a second braid wire (32), and wherein the movable contact support (62) is sleeved on a second pivot (601) so that the movable contact (61) can rotate between a second closed position and a second open position, and when the movable contact (61) is in the second closed position, the movable contact point (611) abuts against the stationary contact point (221) to hold the stationary contact (20) in the first closed position.

6. The contact assembly (100) of claim 5, characterized in that Further comprising gas generating vanes located on both sides of a rotation track of the movable contact (61).

7. The contact assembly (100) according to claim 1 or 2, wherein the second segment (22) comprises a main body portion (222), and the stationary contact point (221) protrudes from a middle portion of the main body portion (222), and the main body portion (222) is further provided with an arc striking protrusion (223) extending from a side wall of the stationary contact point (221) to a free end of the main body portion (222).

8. The contact assembly (100) of claim 1 or 2, characterized in that The contact pressure piece (40) comprises an elastic piece (41) in abutment with the first section (21).

9. The contact assembly (100) of claim 8, characterized in that The contact pressure piece (40) further comprises: a fixed plate (42) arranged on a housing (80) of the breaking device; and a support piece (43) connected with the fixed plate (42), the elastic piece (41) being sleeved on the support piece (43).

10. A dual power transfer switch, characterized by The dual power transfer switch comprises a breaking device, and the breaking device comprises two contact assemblies (100) of the breaking device as claimed in any one of claims 1 to 9.

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