A knife switch structure

Abstract

This utility model provides a knife switch structure, including a base and a plurality of contact assemblies disposed above the base. The contact assemblies include an inlet contact piece, an outlet contact piece, and a movable knife switch disposed between the inlet and outlet contact pieces. A linkage rod is passed through the movable knife switches, and a drive plate for driving the linkage rod to rotate is fixedly connected to the linkage rod. A positioning plate for connecting the movable knife switch and the linkage rod is provided. This knife switch structure can be applied to high-current equipment and overcomes the defects in the prior art where the three contacts cannot guarantee synchronous movement, which will cause uneven current distribution, concentrated arc erosion, and mechanical impact vibration, ultimately leading to contact welding explosion or mechanism breakage.

Description

Technical Field

[0001] This utility model relates to the field of knife switch technology, and specifically to a knife switch structure. Background Technology

[0002] The core value of a knife switch lies in providing safe and reliable power isolation and a clearly visible break point. It is mainly used for isolating circuits, performing infrequent manual on / off operations, and simple power switching. To solve the three core problems of current distribution, arc control, and mechanical reliability, existing technologies for some high-current knife switches will set three contacts, and each of the three contacts will have a knife switch capable of opening and closing. If the three contacts cannot guarantee synchronous movement, it will cause uneven current distribution, concentrated arc erosion, and mechanical impact vibration, ultimately leading to contact welding explosion or mechanical failure. Utility Model Content

[0003] Therefore, the technical problem to be solved by this utility model is to overcome the defects in the prior art that if the three contacts cannot be guaranteed to move synchronously, it will cause uneven current distribution, concentrated arc erosion and mechanical impact vibration, which will eventually lead to contact welding explosion or mechanism breakage. Thus, a blade structure of a knife switch that can guarantee that the three contacts can move synchronously is provided.

[0004] Therefore, this utility model provides a knife switch structure, including a base and a plurality of contact assemblies disposed above the base. The contact assembly includes an inlet contact piece, an outlet contact piece, and a movable knife switch disposed between the inlet contact piece and the outlet contact piece. A linkage rod is passed through the movable knife switches. A drive plate for driving the linkage rod to rotate is fixedly connected to the linkage rod. A positioning plate for connecting the movable knife switch and the linkage rod is provided between the two.

[0005] Furthermore: one end of the positioning plate is mounted on the linkage rod, and the other end is attached to the side wall of the movable knife switch. The positioning plate and the movable knife switch are connected by fastening nails.

[0006] Furthermore: the incoming and outgoing contact pieces are respectively provided with a first knife clamp contact and a second knife clamp contact. One end of the movable knife switch is hinged to the first knife clamp contact, and the other end can contact or separate from the second knife clamp contact. The movable knife switch has a closed state in contact with the second knife clamp contact and an open state in separation from the second knife clamp contact.

[0007] Furthermore: the first blade clamp contact includes a first left clamp and a first right clamp disposed at the inlet contact plate, and the second blade clamp contact includes a second left clamp and a second right clamp disposed at the outlet contact plate, and a second retaining spring is disposed between the second left clamp and the second right clamp for pressing the two from both sides toward the side closer to the movable blade.

[0008] Furthermore: the incoming and outgoing contact pieces include a copper layer and an aluminum layer, the copper layer being disposed above the aluminum layer, and the copper layer and the aluminum layer being connected by fastening pins.

[0009] Furthermore: the positioning plate includes a rotating end coaxially connected to the linkage rod and a positioning end connected to the movable knife switch, the positioning end being in contact with the side wall of the movable knife switch.

[0010] The technical solution of this utility model has the following advantages:

[0011] 1. This utility model provides a knife switch structure with three sets of contact assemblies on the base. Each set of contact assemblies includes an inlet contact, an outlet contact, and a movable knife switch. The three movable knife switches are connected in series by a linkage rod. A drive plate is linked behind the linkage rod. A push rod that can horizontally push the drive plate is connected to the end of the drive plate facing away from the linkage rod. A gear transmission mechanism is located on the side of the drive plate facing away from the base. A transmission rod is located on the side of the gear transmission mechanism facing away from the drive plate. When the switch is manually opened or closed, the transmission rod swings clockwise or counterclockwise, thereby swinging through the gear mechanism and driving the push rod to move back and forth. The push rod can drive the linkage rod to rotate while pushing and pulling back and forth. Since a positioning plate is set between the linkage rod and the movable knife switch, the three positioning plates connect the linkage rod and the three movable knife switches together. When the linkage rod swings, it can drive the three movable knife switches to move synchronously, thereby causing the movable knife switch to separate from the outlet contact and realize the opening of the switch. This transmission structure is stable and can be used for high-current equipment.

[0012] 2. The knife switch structure provided by this utility model has a positioning plate arranged in a triangular structure. One end of the positioning plate is coaxially arranged with the linkage rod. When the linkage rod rotates, it will drive the positioning plate to flip. The positioning plate drives the linkage rod to flip, which in turn drives the movable knife switch to separate from the outgoing contact piece, thereby realizing the opening of the switch. Attached Figure Description

[0013] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the overall structure of the contact assembly;

[0015] Figure 2 This is a schematic diagram of the front structure of the contact assembly;

[0016] Figure 3This is another overall structural diagram of the contact assembly;

[0017] Figure 4 This is a schematic diagram of the side structure of the contact assembly;

[0018] Figure 5 This is a diagram showing the positional relationship between the contact assembly and the push rod.

[0019] Explanation of reference numerals in the attached figures:

[0020] 1. Base; 11. Push rod; 12. Gear transmission mechanism; 13. Transmission rod; 2. Contact assembly; 21. Inlet contact piece; 22. Outlet contact piece; 23. Movable knife switch; 24. Copper layer; 25. Aluminum layer; 3. Linkage rod; 4. Drive plate; 5. Positioning plate; 51. Rotating end; 52. Positioning end; 6. First knife clamp contact; 61. First left clamp piece; 62. First right clamp piece; 7. Second knife clamp contact; 71. Second left clamp piece; 72. Second right clamp piece; 73. Second snap ring. Detailed Implementation

[0021] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0022] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0024] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0025] Example

[0026] This embodiment provides a knife switch structure, including a base 1 and a plurality of contact assemblies 2 disposed above the base 1. The contact assembly 2 includes an inlet contact piece 21, an outlet contact piece 22, and a movable knife switch 23 disposed between the inlet contact piece 21 and the outlet contact piece 22. A linkage rod 3 is passed through the movable knife switches 23. A drive plate 4 for driving the linkage rod 3 to rotate is fixedly connected to the linkage rod 3. A positioning plate 5 for connecting the movable knife switch 23 and the linkage rod 3 is provided.

[0027] The specific improvements mentioned above are as follows: Figure 1 , Figure 4 as well as Figure 5 As shown, three sets of contact assemblies 2 are installed on the base 1. Each set of contact assemblies 2 includes an inlet contact piece 21, an outlet contact piece 22, and a movable knife switch 23. The three movable knife switches 23 are connected in series by a linkage rod 3. A drive plate 4 is linked behind the linkage rod 3. The end of the drive plate 4 facing away from the linkage rod 3 is connected to a push rod 11 that can horizontally push the drive plate 4. There is a gear transmission mechanism 12 on the side of the drive plate 4 facing away from the base 1. There is a transmission rod 13 on the side of the gear transmission mechanism 12 facing away from the drive plate 4. When the switch is manually opened or closed... When the transmission rod 13 swings clockwise or counterclockwise, it swings through the gear mechanism, thereby driving the push rod 11 to move back and forth. While the push rod 11 pushes and pulls back and forth, it can drive the linkage rod 3 to rotate. Since the linkage rod 3 and the movable knife switch 23 are provided with positioning plates 5, the three positioning plates 5 connect the linkage rod 3 and the three movable knife switches 23 together. When the linkage rod 3 swings, it can drive the three movable knife switches 23 to move synchronously, thereby causing the movable knife switch 23 to separate from the outgoing contact piece 22 to achieve circuit breaking. This transmission structure is stable and can be used for high current equipment.

[0028] Based on the above embodiments: one end of the positioning plate 5 is disposed on the linkage rod 3, and the other end is attached to the side wall of the movable knife switch 23. The positioning plate 5 and the movable knife switch 23 are connected by fastening nails.

[0029] The specific improvements mentioned above are as follows: Figures 1-3 As shown, the positioning plate 5 is arranged in a triangular structure. One end of the positioning plate 5 is coaxially arranged with the linkage rod 3. When the linkage rod 3 rotates, it will drive the positioning plate 5 to flip. The positioning plate 5 drives the linkage rod 3 to flip, which in turn drives the movable knife switch 23 to separate from the outgoing contact piece 22, thereby realizing the circuit breaker opening.

[0030] Based on the above embodiments: the incoming contact 21 and the outgoing contact 22 are respectively provided with a first knife clamp contact 6 and a second knife clamp contact 7. One end of the movable knife switch 23 is hinged to the first knife clamp contact 6, and the other end can contact or separate from the second knife clamp contact 7. The movable knife switch 23 has a closed state in contact with the second knife clamp contact 7 and an open state in separation from the second knife clamp contact 7.

[0031] The specific improvements mentioned above are as follows: Figure 3 As shown, the incoming contact piece 21 is provided with a first knife clamp contact 6, and the outgoing contact piece is provided with a second knife clamp contact 7. One end of the movable knife switch 23 is hinged to the first knife clamp contact 6, and the other end is flipped along the hinge point, so that the movable knife switch 23 can switch between the open state and the closed state.

[0032] Based on the above embodiments: the first blade clamp contact 6 includes a first left clamp 61 and a first right clamp 62 disposed at the inlet contact 21, and the second blade clamp contact 7 includes a second left clamp 71 and a second right clamp 72 disposed at the outlet contact 22. A second retaining spring 73 is disposed between the second left clamp 71 and the second right clamp 72 to press them together from both sides toward the side closer to the movable blade.

[0033] The specific improvements mentioned above are as follows: Figure 3 As shown, the first knife-clamp contact 6 includes a first left clamp 61 and a first right clamp 62, which clamp the movable knife switch 23 in the middle. Similarly, the second knife-clamp contact 7 includes a second left clamp 71 and a second right clamp 72 disposed at the outgoing contact 22. When the movable knife switch 23 is in the closed state, the second left clamp 71 and the second right clamp 72 will clamp the movable knife switch 23. In order to increase the contact force between the second left clamp 71 and the second right clamp 72, a retaining spring is provided between the second left clamp 71 and the second right clamp 72. One end of the retaining spring is connected to the second... The left clip 71 abuts against the second right clip 72, and the spring force of the retaining spring acts on the second left clip 71 and the second right clip 72, making them fit more tightly with the movable knife switch 23. The setting of the second retaining spring 73 effectively provides a more stable and longer-lasting contact pressure, significantly improving the reliability and long-term stability of the contact between the two left clips, the second right clip 72 and the movable knife switch 23, reducing contact resistance and temperature rise, extending service life, and reducing the risk of poor contact or sparks between the two left clips, the second right clip 72 and the movable knife switch 23 due to vibration.

[0034] Based on the above embodiments: the incoming contact 21 and the outgoing contact 22 include a copper layer 24 and an aluminum layer 25, the copper layer 24 is disposed above the aluminum layer 25, and the copper layer 24 and the aluminum layer 25 are connected by fastening nails.

[0035] The specific improvements mentioned above are as follows: Figure 3 As shown, to save production costs, the inlet contact 21 and outlet contact 22 are replaced with copper layer 24 and aluminum layer 25 instead of the original all-copper material. Based on experimental data, the results are as follows:

[0036] For a low-voltage circuit breaker with a specified thermal current of 600A, the temperature rise of the copper structure is 25.7K and the short-time withstand current (icw) is 25KA / 1s, while the temperature rise of the copper + aluminum structure is 31.7K and the short-time withstand current (icw) is 20KA / 1s.

[0037] For a low-voltage circuit breaker with a specified thermal current of 1000A, the temperature rise of the copper structure is 30.1K and the short-time withstand current (icw) is 30KA / 1s, while the temperature rise of the copper + aluminum structure is 31.1K and the short-time withstand current (icw) is 25KA / 1s.

[0038] For a low-voltage circuit breaker with a specified thermal current of 1500A, the temperature rise of the copper structure is 52.2.1K and the short-time withstand current (icw) is 40KA / 1s, while the temperature rise of the copper + aluminum structure is 54.9K and the short-time withstand current (icw) is 35KA / 1s.

[0039] Experimental data shows that replacing the original all-copper material with copper layer 24 and aluminum layer 25, although the performance is slightly lower than the original structure, still meets the standard of GB / T14048.3, but the cost can be reduced significantly.

[0040] Based on the above embodiments: the positioning plate 5 includes a rotating end 51 coaxially connected to the linkage rod 3 and a positioning end 52 connected to the movable knife switch 23, wherein the positioning end 52 is in contact with the side wall of the movable knife switch 23.

[0041] The specific improvements mentioned above are as follows: Figure 3 As shown, the positioning plate 5 includes a rotating end 51 and a positioning end 52. The rotating end 51 has a rotating groove, which is sleeved on the outside of the linkage rod 3 and fixedly connected to the linkage rod 3. The positioning end 52 is attached to the side of the movable knife switch 23, and the positioning end 52 is fastened to the movable knife switch 23 with bolts and nuts, so that when the linkage rod 3 rotates, it can drive the movable knife switch 23 to switch between the open state and the closed state.

[0042] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A knife switch structure, characterized in that: The device includes a base (1) and several contact assemblies (2) disposed above the base (1). Each contact assembly (2) includes an inlet contact piece (21), an outlet contact piece (22), and a movable knife switch (23) disposed between the inlet contact piece (21) and the outlet contact piece (22). A linkage rod (3) is passed through the movable knife switches (23). A drive plate (4) for driving the linkage rod (3) to rotate is fixedly connected to the linkage rod (3). A positioning plate (5) for connecting the movable knife switch (23) and the linkage rod (3) is disposed between the two.

2. The knife switch structure according to claim 1, characterized in that: One end of the positioning plate (5) is set on the linkage rod (3), and the other end is attached to the side wall of the movable knife switch (23). The positioning plate (5) and the movable knife switch (23) are connected by fastening nails.

3. A knife switch structure according to claim 1 or 2, characterized in that: The incoming contact (21) and the outgoing contact (22) are respectively provided with a first knife clamp contact (6) and a second knife clamp contact (7). One end of the movable knife switch (23) is hinged to the first knife clamp contact (6), and the other end can contact or separate from the second knife clamp contact (7). The movable knife switch (23) has a closed state in contact with the second knife clamp contact (7) and a closed state in separation from the second knife clamp contact (7).

4. The knife switch structure according to claim 3, characterized in that: The first blade clamp contact (6) includes a first left clamp (61) and a first right clamp (62) disposed at the inlet contact (21), and the second blade clamp contact (7) includes a second left clamp (71) and a second right clamp (72) disposed at the outlet contact (22). A second retaining ring (73) is disposed between the second left clamp (71) and the second right clamp (72) for pressing the two from both sides toward the side closer to the movable blade.

5. The knife switch structure according to claim 4, characterized in that: The incoming contact (21) and the outgoing contact (22) include a copper layer (24) and an aluminum layer (25), with the copper layer (24) disposed above the aluminum layer (25), and the copper layer (24) and the aluminum layer (25) connected by fastening pins.

6. The knife switch structure according to claim 5, characterized in that: The positioning plate (5) includes a rotating end (51) coaxially connected to the linkage rod (3) and a positioning end (52) connected to the movable knife switch (23). The positioning end (52) is in contact with the side wall of the movable knife switch (23).

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