Air circuit breaker short-circuit grounding wire connection terminal clamp

Abstract

This utility model discloses a clamp for connecting short-circuit grounding wires of circuit breakers, including a fixed clamping arm, a movable clamping arm, a fixed base, and a screw. The fixed clamping arm includes a clamping part and a connecting part. The clamping part is arranged opposite to the movable clamping arm for clamping the target terminal, and the connecting part slides through the movable clamping arm and is fixedly connected to the fixed base. The screw is threaded through the fixed base, and its end is rotatably connected to the movable clamping arm. A first insulating operating part is provided on the side wall of the fixed base, and a second insulating operating part is provided at the end of the screw away from the movable clamping arm. This utility model achieves precise and controllable clamping and releasing in a confined space by driving the movable clamping arm to slide along the fixed clamping arm via the screw. By providing insulating operating parts on the fixed base and the screw, it ensures that the operator can apply operating force under safe insulation, solving the problems of traditional clamps being unable to operate due to insufficient space or insufficient spring clamping force.

Description

Technical Field

[0001] This utility model relates to the field of low-voltage power distribution network maintenance, specifically to a clamp for connecting short-circuit grounding wires of circuit breakers. Background Technology

[0002] In low-voltage power distribution networks, air circuit breakers (hereinafter referred to as "circuit breakers") are widely used electrical protection devices. When performing power outage maintenance work on the lower terminals of circuit breakers, connecting a short-circuit grounding wire is a crucial step to ensure the safety of workers and prevent backfeeding.

[0003] Currently, the portable grounding clamps commonly used by operators are designed for conductors with ample operating space, such as overhead lines or cable terminals. However, the actual structure of the circuit breaker lower terminal has significant space limitations: firstly, the spacing between adjacent lower terminal bolts is narrow, typically only about 22 mm; secondly, the effective vertical operating space around the lower terminal bolt is usually less than 40 mm; and thirdly, the exposed conductive part of the bolt itself is short, typically only 5 to 10 mm.

[0004] The spatial characteristics of the lower terminal of a circuit breaker present significant challenges to the application of traditional grounding clamps. Standard-sized clamps, generally exceeding 55 mm in width, cannot fit into confined installation spaces. While some marketed "mini" narrow clamps may fit physically, their design suffers from inherent flaws: in pursuit of a smaller size, the contact area between the clamp and bolt is excessively sacrificed, leading to increased contact resistance and insufficient current carrying capacity. Furthermore, these clamps typically rely on simple spring mechanisms for clamping force, resulting in weak and unreliable holding power. They are highly susceptible to loosening under slight vibrations or electrodynamic impacts from short-circuit currents, posing a serious safety hazard. When a safe and reliable grounding wire cannot be safely and reliably connected to the target circuit breaker's lower terminal, workers are forced to adopt a conservative strategy of expanding the power outage area by disconnecting the upstream main switch and grounding. While this ensures personnel safety, it undoubtedly expands the outage area, prolongs the outage time, reduces power supply reliability, and may lead to customer complaints.

[0005] Therefore, there is an urgent need in this field for a new type of short-circuit grounding wire clamp to solve the above problems. Utility Model Content

[0006] The purpose of this utility model is to provide a short-circuit grounding wire clamp to solve the problems of weak clamping force and unreliability of existing grounding wire clamps.

[0007] To solve the above-mentioned technical problems, this utility model provides a clamp for hanging the short-circuit grounding wire of a circuit breaker, including a fixed clamping arm, a movable clamping arm, a fixed base and a screw.

[0008] The fixed clamping arm includes a clamping part and a connecting part; the clamping part is arranged opposite to the movable clamping arm for clamping the target terminal, and the connecting part slides through the movable clamping arm and is fixedly connected to the fixed base; the screw thread passes through the fixed base, and its end is rotatably connected to the movable clamping arm.

[0009] The fixed base has a first insulating operating part on its side wall, and the screw has a second insulating operating part at the end away from the movable clamping arm.

[0010] Furthermore, the first insulating operating part is a U-shaped handle, with both ends of the handle rotatably connected to the side wall of the fixed base, so that the handle can be flipped up and down along the connection point between the handle and the side wall of the fixed base.

[0011] Furthermore, the side of the clamping part of the fixed clamping arm is provided with a limiting plate that matches the gap between the connecting seat of the lower pile head bolt of the circuit breaker.

[0012] Furthermore, the clamping part of the fixed clamping arm is curved to match the shape of the lower pile head bolt of the circuit breaker.

[0013] Furthermore, the side of the movable clamping arm facing the fixed seat is provided with a limiting groove that cooperates with the screw; the end of the screw connected to the movable clamping arm extends into the limiting groove, and the limiting groove is provided with a limiting mechanism to prevent the screw from exiting the limiting groove.

[0014] Furthermore, one end of the screw extending into the limiting groove is provided with an annular groove arranged along the circumference of the screw; the limiting mechanism includes a fixing pin arranged laterally in the limiting groove; the fixing pin passes through the groove laterally, and the diameter of the fixing pin is smaller than the distance between the two side walls of the groove.

[0015] Furthermore, the side of the fixing base is provided with a threaded terminal, and a clamping nut is provided on the threaded terminal, and the grounding wire end is clamped between the fixing base and the clamping nut.

[0016] Furthermore, the second insulating operating part is a knob that is fixedly connected to the screw.

[0017] Furthermore, the knob has several protrusions on its side wall.

[0018] The beneficial effects of this utility model are as follows: by driving the movable clamping arm to slide along the fixed clamping arm through the screw, precise and controllable clamping and releasing in a narrow space is achieved; by setting an insulated operating part on the fixed seat and the screw, it is ensured that the operator can apply operating force under the premise of safe insulation, which solves the problem that traditional chucks cannot be operated due to insufficient space or insufficient spring clamping force. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, use the same reference numerals to denote the same or similar parts. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0020] Figure 1 This is a schematic diagram of the structure when the clamp of the short-circuit grounding wire connection terminal of the circuit breaker is in the loose state.

[0021] Figure 2 This is a schematic diagram of the structure when the clamp of the short-circuit grounding wire connection terminal of the circuit breaker is in the clamped state.

[0022] Figure 3 This is a cross-sectional view of the clamp at the short-circuit grounding wire connection end of the circuit breaker.

[0023] Figure 4 This is a schematic diagram of the structure in which the short-circuit grounding wire clamp is held in place by the bolt on the lower terminal of the circuit breaker.

[0024] Among them: 1. Fixed clamping arm; 11. Limiting plate; 2. Movable clamping arm; 21. Fixed pin; 3. Fixed seat; 4. Threaded terminal block; 41. Clamping nut; 5. Handle; 6. Screw; 61. Groove; 7. Knob; A1. Bottom bolt of circuit breaker. Detailed Implementation

[0025] like Figures 1 to 3 The circuit breaker short-circuit grounding wire clamp shown includes a fixed clamping arm 1, a movable clamping arm 2, a fixed base 3, and a screw 6. The fixed clamping arm 1 includes a clamping part and a connecting part. The clamping part is arranged opposite to the movable clamping arm 2 for clamping the target terminal. The connecting part slides through the movable clamping arm 2 and is fixedly connected to the fixed base 3. The screw 6 is threaded through the fixed base 3, and its end is rotatably connected to the movable clamping arm 2. The side wall of the fixed base 3 is provided with a first insulating operating part, and the end of the screw 6 away from the movable clamping arm 2 is provided with a second insulating operating part.

[0026] During wiring, the clamping part of the fixed clamping arm 1 is first hooked directly onto the target circuit breaker lower terminal bolt A1. Then, the movable clamping arm 2 is driven to slide along the fixed clamping arm 1 by turning the screw 6, achieving precise and controllable clamping and releasing in a confined space. By setting insulated operating parts on the fixed seat 3 and the screw 6, it is ensured that the operator can apply operating force under safe insulation, solving the problem of traditional chucks being unable to operate due to insufficient space or insufficient spring clamping force. The screw 6 can be made of M6 stainless steel screw rod, with a clamping force of up to 120N, ensuring stable and reliable clamping. The movable clamping arm 2, the fixed clamping arm 1, and the fixed seat 3 are made of copper as the main material to ensure current carrying capacity. The outer triangular aluminum alloy structure increases mechanical strength.

[0027] According to one embodiment of this application, the first insulating operating part is a U-shaped handle 5. Both ends of the handle 5 are rotatably connected to the sidewalls of the fixed base 3, allowing the handle 5 to rotate up and down along the connection point between the handle 5 and the sidewalls of the fixed base 3. This embodiment, by employing a U-shaped reversible handle 5, provides multiple angles and convenient force application points, enabling the operator to find a convenient direction to apply force and stabilize the entire chuck even in various confined spaces near the switch, greatly improving operational convenience and adaptability. Furthermore, after operation, the U-shaped handle 5 can be rotated to the side closer to the fixed base 3 to avoid affecting the installation of adjacent chucks, such as... Figure 4 As shown.

[0028] According to one embodiment of this application, the side of the clamping part of the fixed clamping arm 1 is provided with a limiting plate 11 that matches the gap between the connecting seat of the lower pile head bolt A1 of the circuit breaker. In this embodiment, by providing the limiting plate 11, the clamp is engaged in the gap between the lower pile head bolt A1 of the circuit breaker and the connecting seat during connection, effectively preventing the clamping part of the fixed clamping arm 1 from slipping off the lower pile head bolt A1 of the circuit breaker, thus improving the stability and efficiency of the connection.

[0029] According to one embodiment of this application, the clamping portion of the fixed clamping arm 1 is curved to match the shape of the circuit breaker lower pile head bolt A1. This embodiment, by employing a curved clamping portion that fits against the curved surface of the cylindrical circuit breaker lower pile head bolt A1, transforms traditional line or point contact into a larger surface contact, thereby significantly increasing the effective contact area, reducing contact resistance, and improving current carrying capacity and electrical connection reliability.

[0030] According to one embodiment of this application, the movable clamping arm 2 has a limiting groove on the side facing the fixed base 3 that cooperates with the screw 6; one end of the screw 6 connected to the movable clamping arm 2 extends into the limiting groove, and a limiting mechanism is provided in the limiting groove to prevent the screw 6 from exiting the limiting groove. This embodiment, through the cooperation of the limiting groove and the limiting mechanism, allows relative rotation between the screw 6 and the movable clamping arm 2, but prevents the screw 6 from axially disengaging from the movable clamping arm 2, ensuring the integrity of the transmission mechanism at all times, avoiding separation of the screw 6 from the clamping arm during repeated operation or carrying, and improving the durability and reliability of the product.

[0031] According to one embodiment of this application, one end of the screw 6 extending into the limiting groove is provided with an annular groove 61 arranged circumferentially along the screw 6; the limiting mechanism includes a fixing pin 21 laterally arranged in the limiting groove; the fixing pin 21 laterally penetrates the groove 61, and the diameter of the fixing pin 21 is smaller than the distance between the two side walls of the groove 61. This embodiment, by using the cooperation of the annular groove 61 and the transverse fixing pin 21, allows the fixing pin 21 to be inserted into the limiting groove from the outside of the movable clamping arm 2 and pass through the groove 61 on the screw 6, thus forming a simple, reliable and easy-to-manufacture limiting mechanism; its structure is compact, does not increase the volume of the chuck, and is very suitable for use in chucks with limited space requirements.

[0032] According to one embodiment of this application, the side of the fixing base 3 is provided with a threaded terminal 4, and a clamping nut 41 is provided on the threaded terminal 4. The grounding wire head is clamped between the fixing base 3 and the clamping nut 41. This embodiment can achieve quick connection by using a crimping grounding wire head, which can reduce the operation time to 5-7 minutes; and the bolt crimping method is a firm, reliable grounding wire connection method that conforms to electrical connection specifications. It can ensure that the connection resistance between the grounding wire and the clamp body is extremely small and can withstand the impact of short-circuit current, preventing safety accidents caused by loose connection points or overheating.

[0033] According to one embodiment of this application, the second insulating operating part is a knob 7 fixedly connected to the screw 6. The knob 7 used in this embodiment has a simple structure and is easy to rotate to apply force.

[0034] According to one embodiment of this application, the side wall of the knob 7 is provided with several protrusions, such as a hard plastic plum blossom knob 7. By providing protrusions on the knob 7, this embodiment can effectively prevent hand slippage during operation, especially when wearing gloves or with sweaty hands, and ensure sufficient torque when rotating the screw 6, thereby guaranteeing sufficient clamping force.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A clamp for connecting a short-circuit grounding wire of a circuit breaker, characterized in that, Includes a fixed clamping arm, a movable clamping arm, a fixed base, and a screw; The fixed clamping arm includes a clamping part and a connecting part; the clamping part is disposed opposite to the movable clamping arm for clamping the target terminal, and the connecting part slides through the movable clamping arm and is fixedly connected to the fixed base; the screw thread passes through the fixed base, and its end is rotatably connected to the movable clamping arm. The fixed base has a first insulating operating part on its side wall, and the screw has a second insulating operating part at the end away from the movable clamping arm.

2. The air opening shorting ground wire hanger collet of claim 1, wherein, The first insulating operating part is a U-shaped handle, and the two ends of the handle are rotatably connected to the side wall of the fixed base, so that the handle can be flipped up and down along the connection point between the handle and the side wall of the fixed base.

3. The air opening shorting ground wire hanger collet of claim 1, wherein, The side of the clamping part of the fixed clamping arm is provided with a limiting plate that matches the gap between the connecting seat of the lower pile head bolt of the circuit breaker.

4. The open short ground hanger terminal collet of claim 1 or 3, wherein, The clamping part of the fixed clamping arm is curved to match the shape of the bottom pile head bolt of the circuit breaker.

5. The air opening shorting ground wire hanger collet of claim 1, wherein, The movable clamping arm has a limiting groove on the side facing the fixed base that cooperates with the screw; the end of the screw connected to the movable clamping arm extends into the limiting groove, and the limiting groove is provided with a limiting mechanism to prevent the screw from exiting the limiting groove.

6. The short-circuit grounding wire clamp according to claim 5, characterized in that, One end of the screw extending into the limiting groove is provided with an annular groove arranged along the circumference of the screw; the limiting mechanism includes a fixing pin arranged laterally in the limiting groove; the fixing pin extends laterally through the groove, and the diameter of the fixing pin is smaller than the distance between the two side walls of the groove.

7. The short-circuit grounding wire clamp according to claim 1, characterized in that, The side of the fixed base is provided with a threaded terminal, and a clamping nut is provided on the threaded terminal. The grounding wire end is clamped between the fixed base and the clamping nut.

8. The short-circuit grounding wire clamp according to claim 1, characterized in that, The second insulating operating part is a knob that is fixedly connected to the screw.

9. The short-circuit grounding wire clamp according to claim 8, characterized in that, The knob has several protrusions on its side wall.

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