Special grounding wire for voltage transformer of static frequency conversion starting system

Abstract

The utility model relates to a special grounding wire for a voltage transformer of a static frequency conversion starting system, which comprises a clamping assembly used for clamping a spherical pile head, and the clamping assembly comprises a clamping seat and a clamping plate. The clamping plate can move up and down in the semi-surrounding cavity of the clamping seat, the top of the spherical pile head extending between the top wall of the main body part and the clamping plate gradually makes contact with the first ball groove along with the relative approaching of the clamping plate and the clamping seat, and the bottom of the spherical pile head gradually makes contact with the second ball groove along with the continuous approaching of the top wall of the main body part and the clamping plate. The matching positions of the spherical pile head and the first ball groove and the second ball groove can be automatically adjusted until the spherical pile head is completely clamped, and the outer surface of the spherical pile head is completely in contact fit with the inner surfaces of the first ball groove and the second ball groove, so that the contact surface is increased, the connection stability is improved, the contact resistance is reduced, and the use safety is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of grounding wires, and particularly refers to a special grounding wire for a potential transformer of a static frequency conversion starting system. Background Art

[0002] The special grounding wire of the static frequency conversion starting system (hereinafter referred to as the "SFC system") of the pumped storage power station unit is used for discharging and grounding high-voltage equipment during the power outage of the SFC system to protect the safety of maintenance personnel and equipment. The special grounding wire mainly consists of four components: a grounding clamp, a power connection clamp, an operating screw rod, and a grounding cable. It is mainly installed at the three-phase copper bars of the AC reactor, transformer, and potential transformer of the SFC system and is connected to the grounding point through the grounding cable.

[0003] In the potential transformer cabinet of the SFC system, three-phase copper bars and a grounding copper bar are installed. The hanging points of the power connection clamp and the grounding clamp of the copper bar are spherical pile heads. The contact surfaces of the hooks and the clamping plates of the existing grounding wire for power connection and grounding are usually flat. When installing the grounding wire on this spherical pile head, the contact area between the clamping plate and the hanging point is small, and the sphere and the plane are not well-matched, resulting in the problem that the power connection clamp is likely to fall off, affecting the unstable connection of the grounding wire, and having too large contact resistance, posing a safety hazard.

[0004] Therefore, for the current special grounding wire structure of the potential transformer of the static frequency conversion starting system, further improvement is needed. Summary of the Utility Model

[0005] The technical problem to be solved by the utility model is to provide a special grounding wire for a potential transformer of a static frequency conversion starting system that can increase the contact area to improve the connection stability and reduce the contact resistance to improve the use safety, in view of the current situation of the prior art.

[0006] The technical solution adopted by the utility model to solve the above technical problem is as follows:

[0007] A special grounding wire for a potential transformer of a static frequency conversion starting system includes a clamping component for clamping a spherical pile head. The clamping component includes:

[0008] A clamping seat having a main body portion in a U-shaped structure. The U-shaped structure is horizontally arranged with an opening facing one side. The first vertical portion of the U-shaped structure forms the top wall of the main body portion, and the second vertical portion of the U-shaped structure forms the bottom wall of the main body portion;

[0009] A clamping plate that can move up and down in the semi-enclosed cavity of the U-shaped structure. A second spherical groove is recessed downward on the upper surface of the clamping plate. Correspondingly, a first spherical groove is recessed upward on the lower surface of the top wall of the U-shaped structure. When the first spherical groove and the second spherical groove are relatively close to each other, they form a clamping groove for clamping and limiting the spherical pile head;

[0010] Further comprising:

[0011] A screw rod, the upper end of which passes through the bottom wall of the main body part and is rotatably connected to the clamping plate;

[0012] An operating rod, detachably connected to the lower end of the screw rod, for driving the screw rod to move up and down relative to the clamping seat.

[0013] As an improvement, a notch extending inward from the edge is formed on the top wall of the main body part, and the notch divides the first ball groove into a first part and a second part which are respectively arranged on both sides of the connecting shaft of the spherical stud. The first part, the second part and the second ball groove below them jointly form a structure surrounded by three supporting surfaces on the outer peripheral surface of the spherical stud. With the above structure, the first part and the second part are respectively located on both sides above the second ball groove, and the three form a surrounding structure of three supporting surfaces on the outer peripheral surface of the spherical stud, which is beneficial to maximizing the connectivity and ensuring full contact between the outer surface of the spherical stud and the clamping component, and reducing the contact resistance.

[0014] Preferably, the depth of the first ball groove is less than the depth of the second ball groove, and the notch is arranged corresponding to the central part of the second ball groove. With this structure, the first part and the second part are respectively symmetrically located on both sides above the second ball groove to further improve the connection stability.

[0015] Preferably, a connecting arm extending downward is provided at the bottom of the clamping plate. The inside of the connecting arm is hollow to form an accommodating groove communicating with the second ball groove. A through hole is formed at the bottom of the connecting arm. The upper part of the screw is accommodated in the accommodating groove and the lower end passes through the through hole and is locked and connected to the upper end of the screw rod. The above structure facilitates rotating and restricting the clamping plate at the top of the screw rod. During assembly, it is convenient to install the screw from the second ball groove at the top of the clamping plate downward.

[0016] Preferably, a circumferentially arranged sunk platform is provided at the edge of the upper end of the screw rod, and a gasket is provided on the sunk platform. A guiding edge that can rotate and is sleeved on the upper end of the screw rod and the lower surface of which abuts against the gasket is provided at the bottom edge of the connecting arm. The side surface of the clamping plate facing the inner wall of the U-shaped structure is in contact limit and guiding fit with the inner wall of the U-shaped structure. With the above structure, the rotational stability between the screw rod and the clamping plate is improved, and jamming is avoided.

[0017] Preferably, the lower end of the screw rod is detachably restricted at the upper end of the operating rod through a connecting component, and the connecting component is sleeved on the outer periphery of the screw rod and is in upper and lower plug-in fit with the screw rod.

[0018] Preferably, the connecting assembly includes a connecting sleeve, a limiting post, and an elastic member. The connecting sleeve is disposed at the upper end of the operating rod and at least the upper portion is a tapered sleeve with a larger upper end and a smaller lower end. The central portion of the tapered sleeve forms an assembly hole for the lower end of the screw to pass through. The lower portion of the connecting sleeve is provided with a limiting hole extending radially and communicating with the assembly hole. The circumference of the connecting sleeve is provided with an annular groove located above the limiting hole. The elastic member is annular and disposed in the annular groove. The limiting post is connected to the elastic member and always maintains a tendency to move radially inward along the annular groove. The outer circumference of the screw is provided with a protrusion that can pass through the assembly hole and cooperate with the bottom of the limiting post for limiting position. The upper end of the operating rod is provided with a slot for accommodating the lower end of the screw. With the above structure, the operator can directly insert the lower end of the screw into the connecting sleeve. During the insertion process, the protrusion of the screw will roll with the outer surface of the limiting column when passing through the limiting column and push the elastic part to expand outward with the limiting column. The protrusion moves under the limiting column and enters the limiting hole. At this time, the limiting column is reset under the radial contraction force of the elastic part and limits the top of the protrusion; when the screw needs to be removed from the operating rod, just pull out the screw in the reverse direction.

[0019] Preferably, there are at least two protrusions, symmetrically arranged around the circumference of the screw. The diameter of the circle corresponding to the outer ends of the two corresponding protrusions is larger than the diameter of the lower end of the tapered sleeve. The inner sidewall of the tapered sleeve is provided with a guide opening extending from top to bottom, which allows the protrusions to slide downward into the limiting hole. During the downward insertion of the screw, the guide opening structure not only serves as a clearance for the protrusions, but also provides precise guidance for the protrusions from top to bottom.

[0020] Preferably, the upper edge of the limiting post is arranged corresponding to the lower end of the guide opening, and the inner side wall portion of the limiting post forms a plane that can be arranged close to the outer surface of the screw. This structure is conducive to increasing the positioning force between the limiting post and the outer surface of the screw.

[0021] Preferably, the lower surface of the top wall of the main body part is provided with a concave-convex surface that can prevent it from being tightly attached to the upper surface of the splint; the outer end of the bottom wall of the main body part is provided with a connecting arm that extends obliquely outward and downward for connecting the wiring harness.

[0022] Compared with the prior art, the advantages of the present invention are that the splint of the present invention can move up and down in the semi-enclosed cavity of the clamping seat. As the two get closer to each other, the top of the spherical pile head extending between the top wall of the main body and the splint gradually contacts the first ball groove, and the bottom gradually contacts the second ball groove. As the top wall of the main body and the splint continue to approach each other, the spherical pile head can automatically adjust its matching position with the first ball groove and the second ball groove until the spherical pile head is completely clamped, and the outer surface of the spherical pile head is completely in contact with the inner surfaces of the first ball groove and the second ball groove, which not only increases the contact surface and improves the connection stability, but also reduces the contact resistance, which is conducive to improving the safety of use. Brief Description of the Drawings

[0023] Figure 1 is a schematic structural view of an embodiment of the present utility model;

[0024] Figure 2 is Figure 1 a sectional view of;

[0025] Figure 3 is Figure 1 a partial sectional view from another angle;

[0026] Figure 4 is Figure 1 an exploded view of;

[0027] Figure 5 is a view of the working state of an embodiment of the present utility model. Detailed Embodiment

[0028] The following further describes the present utility model in detail in conjunction with the embodiments of the drawings.

[0029] As Figures 1 to 5 shown, the special grounding wire of the voltage transformer of the static frequency conversion starting system in this embodiment includes a clamping component A for clamping the spherical pile head, a screw 3, an operating rod 4 and a connecting component 5.

[0030] The above clamping component A includes a clamping seat 1 and a clamping plate 2. The clamping seat 1 has a main body part with a U-shaped structure, the U-shaped structure is horizontally arranged and the opening faces one side, the first vertical part of the U-shaped structure constitutes the top wall 11 of the main body part, and the second vertical part of the U-shaped structure constitutes the bottom wall 12 of the main body part. The clamping plate 2 is arranged in the semi-enclosed cavity of the U-shaped structure so as to be movable up and down. A second ball groove 21 is formed by downward depression on the upper surface of the clamping plate 2. Correspondingly, a first ball groove 111 is formed by upward depression on the lower surface of the top wall 11 of the U-shaped structure. When the first ball groove 21 and the second ball groove 111 are relatively close to each other, a clamping groove for clamping and limiting the spherical pile head 6 is formed. The upper end of the above screw 3 passes through the bottom wall 12 of the main body part and is rotatably connected to the clamping plate 2. The operating rod 4 is detachably connected to the lower end of the screw 3 through the connecting component 5 for driving the screw 3 to move up and down relative to the clamping seat 1.

[0031] In this embodiment, as Figure 3As shown, a notch 112 extending inward from the edge is formed in the top wall 11 of the main body part. The notch 112 divides the first ball groove 111 into a first part 01 and a second part 02 which are arranged on both sides of the connecting shaft 61 of the spherical stud 6 respectively. The first part 01, the second part 02 and the second ball groove 21 below them together form a structure that surrounds the outer peripheral surface of the spherical stud 6 with three supporting surfaces. With the above structure, the first part 01 and the second part 02 are respectively located on both sides above the second ball groove 21, and the three form a surrounding structure with three supporting surfaces on the outer peripheral surface of the spherical stud 6, which is beneficial to maximizing the connectivity and ensuring full contact between the outer surface of the spherical stud 6 and the clamping component A, thereby reducing the contact resistance.

[0032] The depth of the first ball groove 111 is less than that of the second ball groove 21, and the notch 112 is arranged corresponding to the central part of the second ball groove 21. With this structure, the first part 01 and the second part 02 are symmetrically located on both sides above the second ball groove 21 respectively, so as to further improve the connection stability.

[0033] In this embodiment, a connecting arm 22 extending downward is provided at the bottom of the clamping plate 2. The inside of the connecting arm 22 is hollow to form a receiving groove 23 communicating with the second ball groove 21. A through hole 221 is formed at the bottom of the connecting arm 22. The upper part of the screw 24 is received in the receiving groove 23 and the lower end passes through the through hole 221 and is locked and connected to the upper end of the screw rod 3. A threaded hole 120 for the screw rod 3 to pass through is formed in the bottom wall 12. The above structure facilitates the rotational constraint of the clamping plate 2 at the top of the screw rod 3. During assembly, it is convenient to install the screw 24 downward from the second ball groove 21 at the top of the clamping plate 2.

[0034] A circumferentially arranged sunk platform 31 is provided at the edge of the upper end of the screw rod 3. A gasket 32 is provided on the sunk platform 31. A guiding edge 222 that can rotate is provided at the bottom edge of the connecting arm 22 and is sleeved on the upper end of the screw rod 3 and its lower surface abuts against the gasket 32. The side surface 25 of the clamping plate 2 facing the inner wall of the U-shaped structure is in contact limit and guiding fit with the inner wall of the U-shaped structure. With the above structure, the rotational stability between the screw rod 3 and the clamping plate 2 is improved to avoid jamming.

[0035] In this embodiment, the lower end of the screw rod 3 is detachably constrained at the upper end of the operating rod 4 through a connecting component 5. The connecting component 5 is sleeved on the outer periphery of the screw rod 3 and is in upper and lower plug-in fit with the screw rod 3.

[0036] Specifically, the connecting assembly 5 comprises a connecting sleeve 51, a limiting post 52, and an elastic member 53. The connecting sleeve 51 is attached to the upper end of the operating rod 4 and can be screwed, welded, or otherwise connected. At least the upper portion of the connecting sleeve 51 is a tapered sleeve with a larger upper end and a smaller lower end. A central portion of the tapered sleeve forms an assembly hole 511 through which the lower end of the screw rod 3 passes. A limiting hole 512 extending radially and communicating with the assembly hole 511 is defined at the lower portion of the connecting sleeve 51. An annular groove 513 is defined around the connecting sleeve 51, positioned above the limiting hole 512. The elastic member 53 is annular and disposed within the annular groove 513. Two limiting posts 52 are symmetrically connected to the elastic member 53 and maintain a tendency to move radially inward along the annular groove 513. A protrusion 33 is provided on the outer circumference of the screw rod 3, capable of passing through the assembly hole 511 and engaging with the bottom of the limiting post 52 for retaining position. A slot 41 is defined at the upper end of the operating rod 4, into which the lower end of the screw rod 3 is received. With the above structure, the operator can directly insert the lower end of the screw 3 into the connecting sleeve 51. During the insertion process, the boss 33 of the screw 3 will roll with the outer surface of the limiting column 52 when passing through the limiting column 52 and push the elastic member 53 to expand outward with the limiting column 52. The boss 33 moves under the limiting column 52 and enters the limiting hole 512. At this time, the limiting column 52 is reset under the radial contraction force of the elastic member 53 and limits the top of the boss 33; when the screw 3 needs to be removed from the operating rod 4, the screw 3 can be pulled out in the reverse direction.

[0037] There are at least two protrusions 33, symmetrically arranged around the circumference of the screw 3. The diameter of the circle corresponding to the outer ends of the two corresponding protrusions 33 is larger than the diameter of the lower end of the tapered sleeve. The inner wall of the tapered sleeve is provided with a guide opening 514 extending from top to bottom, allowing the protrusions 33 to slide downward into the stop hole 512. During the downward insertion of the screw 3, the guide opening 514 not only serves as a clearance for the protrusions 33, but also provides precise guidance for the protrusions 33 from top to bottom.

[0038] The upper edge of the limiting post 52 is arranged corresponding to the lower end of the guide opening 514, and the inner side wall of the limiting post 52 forms a plane 521 that can be arranged close to the outer surface of the screw 3. This structure is conducive to increasing the positioning force between the limiting post 52 and the outer surface of the screw 3.

[0039] In this embodiment, the lower surface of the top wall 11 of the main body is provided with a concave-convex surface 113 to prevent it from being tightly attached to the upper surface of the clamping plate 2; the outer end of the bottom wall 12 of the main body is provided with a connecting arm 121 extending obliquely outward and downward for connecting the wiring harness.

[0040] The splint 2 of this embodiment can move up and down in the semi-enclosed cavity of the clamping seat 1. As the two approach each other relatively, the top of the spherical stud 6 extending between the top wall 11 of the main body part and the splint 2 gradually contacts the first ball groove 111, and the bottom gradually contacts the second ball groove 21. And as the top wall 11 of the main body part and the splint 2 continue to approach, the spherical stud 6 can automatically adjust its mating positions with the first ball groove 111 and the second ball groove 21 until the spherical stud 6 is completely clamped. The outer surface of the spherical stud 6 is in complete contact and fit with the inner surfaces of the first ball groove 111 and the second ball groove 21, which not only increases the contact surface, improves the connection stability, but also reduces the contact resistance, and is beneficial to improving the use safety.

[0041] In the description and claims of the present utility model, directional terms such as "front", "rear", "upper", "lower", "left", "right", "side", "top", "bottom", etc. are used to describe various exemplary structural parts and elements of the present utility model. However, the use of these terms here is only for the purpose of convenient explanation and is determined based on the exemplary orientations shown in the drawings. Since the embodiments disclosed by the present utility model can be arranged in different directions, these directional terms are only for illustration and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to the directions opposite to or consistent with the gravity direction.

Claims

1. A dedicated grounding wire for a voltage transformer of a static variable frequency starting system, comprising a clamping assembly (A) for clamping a spherical pile head (6), characterized in that: The clamping assembly (A) comprises: A clamping seat (1) has a main body portion in a U-shaped structure, the U-shaped structure is arranged transversely and opened toward one side, a first vertical portion of the U-shaped structure constitutes a top wall (11) of the main body portion, and a second vertical portion of the U-shaped structure constitutes a bottom wall (12) of the main body portion; A clamping plate (2) is arranged in a semi-enclosed cavity of the U-shaped structure so as to be movable up and down. A second ball groove (21) that is concave downward is provided on the upper surface of the clamping plate (2). Correspondingly, a first ball groove (111) that is concave upward is provided on the lower surface of the top wall (11) of the U-shaped structure. When the first ball groove (111) and the second ball groove (21) are in a relatively close state, they form a clamping groove for clamping and limiting the ball pile head (6). Also includes: A screw (3), the upper end of which passes through the bottom wall (12) of the main body portion and is rotatably connected to the clamping plate (2); An operating rod (4) is detachably connected to the lower end of the screw rod (3) and is used to drive the screw rod (3) to move up and down relative to the clamping seat (1).

2. The dedicated grounding wire for the voltage transformer of the static frequency conversion starting system according to claim 1, characterized in that: The top wall (11) of the main body portion is provided with a notch (112) extending inward from the edge. The notch (112) divides the first ball groove (111) into a first part (01) and a second part (02) respectively arranged on both sides of the connecting shaft of the spherical pile head (6). The first part (01), the second part (02) and the second ball groove (21) below them together form a structure surrounded by three supporting surfaces on the outer peripheral surface of the spherical pile head (6).

3. The dedicated grounding wire for the voltage transformer of the static frequency conversion starting system according to claim 2, characterized in that: The depth of the first ball groove (111) is smaller than the depth of the second ball groove (21), and the notch (112) is arranged corresponding to the central portion of the second ball groove (21).

4. The dedicated grounding wire for the voltage transformer of the static variable frequency starting system according to claim 1, 2 or 3, characterized in that: The bottom of the splint (2) is provided with a connecting arm (22) extending downward, the interior of the connecting arm (22) is hollow to form a receiving groove (23) connected to the second ball groove (21), and the bottom of the connecting arm (22) is provided with a through hole (221), the upper part of the screw is received in the receiving groove (23) and the lower end passes through the through hole (221) and is locked with the upper end of the screw rod (3).

5. The dedicated grounding wire for the voltage transformer of the static variable frequency starting system according to claim 4, characterized in that: A circumferentially arranged sink (31) is provided at the edge of the upper end of the screw (3), a gasket (32) is provided on the sink (31), and a guide edge (222) is provided at the bottom edge of the connecting arm (22) which is rotatably sleeved on the upper end of the screw (3) and whose lower surface abuts against the gasket (32).

6. The dedicated grounding wire for the voltage transformer of the static variable frequency starting system according to claim 1, 2 or 3, characterized in that: The lower end of the screw rod (3) is detachably restrained at the upper end of the operating rod (4) via a connecting assembly (5); the connecting assembly (5) is sleeved on the outer periphery of the screw rod (3) and is plugged into and fitted with the screw rod (3) in an upper and lower manner.

7. The dedicated grounding wire for the voltage transformer of the static frequency conversion starting system according to claim 6, characterized in that: The connecting assembly (5) includes a connecting sleeve (51), a limiting column (52) and an elastic member (53). The connecting sleeve (51) is arranged at the upper end of the operating rod (4) and at least the upper part is a tapered sleeve with a larger upper end and a smaller lower end. The central part of the tapered sleeve forms an assembly hole (511) for the lower end of the screw (3) to pass through. The lower part of the connecting sleeve (51) is provided with a limiting hole (512) extending radially and communicating with the assembly hole (511). An annular groove (513) is provided on the circumference of (51) and is located above the limiting hole (512). The elastic member (53) is annular and is arranged in the annular groove (513). The limiting column (52) is connected to the elastic member (53) and always maintains a tendency to move radially inward along the annular groove (513). The outer periphery of the screw (3) is provided with a protruding column (33) that can pass through the assembly hole (511) and cooperate with the bottom of the limiting column (52) for limiting.

8. The dedicated grounding wire for the voltage transformer of the static frequency conversion starting system according to claim 7, characterized in that: There are at least two protrusions (33) symmetrically arranged around the screw (3), the diameter of the circle corresponding to the outer ends of the two corresponding protrusions (33) is larger than the diameter of the lower end of the tapered sleeve, and the inner side wall of the tapered sleeve is provided with a guide opening (514) extending from top to bottom for the protrusion (33) to slide from top to bottom into the limiting hole (512).

9. The dedicated grounding wire for the voltage transformer of the static variable frequency starting system according to claim 8, characterized in that: The upper edge of the limiting column (52) is arranged corresponding to the lower end of the guide opening (514), and the inner side wall portion of the limiting column (52) forms a plane (521) that can be arranged close to the outer surface of the screw (3).

10. The dedicated grounding wire for the voltage transformer of the static variable frequency starting system according to claim 1, 2 or 3, characterized in that: The lower surface of the top wall (11) of the main body part is provided with a concave-convex surface (113) capable of preventing it from being tightly attached to the upper surface of the clamping plate (2); the outer end of the bottom wall (12) of the main body part is provided with a connecting arm (121) extending obliquely outward and downward for connecting a wiring harness.

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