A center holding mechanism and a gas insulated switchgear

Abstract

The application discloses a kind of mid-position holding mechanism and gas insulated switchgear in the technical field of electric power switch equipment, mid-position holding mechanism includes compression spring, straight line rod, mid-position holding cylinder, spring fixing device and spring sealing device, the straight line rod is fixed by spring fixing device into the compressed state of less than compression state when preloading, the mid-position holding cylinder is opened along the axis straight line cavity and both ends are opened, respectively, and spring sealing device is used to seal the compression spring in the straight line cavity, the compression height of the compression spring is less than the length of the straight line cavity of the mid-position holding cylinder, the scheme solves the problem of two compression springs in the prior art, and the cost performance is poor, and the beneficial effects of simplifying the structure, saving cost and reducing the volume are achieved.

Description

Technical Field

[0001] This application relates to the field of power switchgear technology, specifically to a neutral position holding mechanism and a gas-insulated switchgear. Background Technology

[0002] For interlocking mechanisms in gas-insulated switchgear, flexible connections in connectors, and switch reset actions in transfer breaking circuits, a neutral position holding mechanism is typically required. Traditional mechanisms that achieve neutral position holding using compression springs require two springs, one for providing the positive and one for the negative axial return force of the output rod. This solution is inefficient. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this application provides a neutral holding mechanism and a gas-insulated switchgear to solve the problems of the prior art requiring two compression springs and having poor cost-effectiveness.

[0004] To achieve the above objectives, this application provides the following technical solution:

[0005] A center-holding mechanism includes a cylindrical helical compression spring, a linear rod, a center-holding cylinder, a spring fixing device, and a sealing spring device. The linear rod is pre-installed and fixed in a compressed state (not fully compressed) by the spring fixing device. The center-holding cylinder has a linear cavity along its axis and is open at both ends, namely a rod-through end and a sealing spring end. The rod-through end is fitted into one end of the linear rod and tightly against one end of the compression spring, so that the linear cavity of the center-holding cylinder is fitted outside the compression spring. The sealing spring end uses a sealing spring device to seal and fix the compression spring inside the linear cavity. The compression height of the compression spring is less than the length of the linear cavity of the center-holding cylinder.

[0006] Preferably, the linear rod is a variable diameter linear rod, the end of which is divided into a spring-passing end and a spring-stopping end. From the spring-stopping end to the spring-passing end, a first diameter, a second diameter, a third diameter, and a fourth diameter are sequentially provided. The first diameter is larger than the inner diameter of the compression spring, the second diameter is less than or equal to the inner diameter of the compression spring, the third diameter is smaller than the second diameter, and the fourth diameter is larger than the third diameter but smaller than the inner diameter of the compression spring. The first diameter serves as a spring fixing device on one side of the compression spring. When the compression spring is pre-installed, it is compressed between the first diameter and the fourth diameter by the spring fixing device on the other side. The length of the linear cavity of the center-position retaining cylinder is equal to the sum of the lengths of the compression spring after pre-installation and the spring fixing device on the other side. The spring-passing end is fitted into the variable diameter linear rod, the spring-stopping end is tightly against the end of the compression spring far from the spring fixing device, and the spring-sealing end uses a spring-sealing device to seal and fix the spring fixing device and the compression spring together within the linear cavity.

[0007] Preferably, the fourth diameter is equal to the second diameter.

[0008] Preferably, the variable diameter straight rod is a variable diameter solid cylinder, and from the stop spring end to the through spring end, it is sequentially a first cylinder, a second cylinder, a third cylinder, and a fourth cylinder, with the first cylinder having a first diameter, the second cylinder having a second diameter, the third cylinder having a third diameter, and the fourth cylinder having a fourth diameter.

[0009] Preferably, the spring fixing device uses a card, which is an open circular sheet with an opening to the center. The diameter of the card is greater than or equal to the outer diameter of the compression spring, the opening diameter is greater than or equal to a third diameter, and the opening diameter is less than a second diameter.

[0010] Preferably, the spring-loaded end of the variable-diameter linear rod is provided with a stud, and the spring-stopping end of the variable-diameter linear rod is provided with a pin hole.

[0011] Preferably, the center-holding cylinder is cylindrical in shape.

[0012] Preferably, the sealing spring end of the center-position retaining cylinder has an internal threaded hole, and the sealing spring device uses a hollow round screw plug with a hole on the end face, which is fastened to the internal threaded hole.

[0013] Preferably, the straight cavity inside the center-holding cylinder uses an inner circular cavity.

[0014] Based on the same inventive concept, this application also discloses a gas-insulated switchgear that uses the aforementioned neutral position holding mechanism.

[0015] Compared to existing technologies, this solution offers the following advantages: The neutral position holding mechanism for gas-insulated switchgear applicable to applications such as three-position switches and their mechanisms achieves its function through a single compression spring. This reduces costs compared to the original structure, and its smaller size better aligns with the miniaturization and compact design principles of power switchgear. The internal rod can axially displace under external force; after the force disappears, the output rod returns to its original neutral position, achieving the position holding effect. The displacement direction can be along both the positive and negative axial directions, with equal displacement distances in both directions. The structure is compact, small in size, and offers better cost-effectiveness than traditional double-spring structures. Attached Figure Description

[0016] Figure 1 This is an exploded view of one embodiment of the present solution;

[0017] Figure 2 This is a front view schematic diagram of one embodiment of the pole in this scheme;

[0018] Figure 3 This is a pre-assembly diagram of an embodiment of the compression spring, rod, and card in this solution;

[0019] Figure 4 This is a schematic cross-sectional view along the axis of one embodiment of the position holding cylinder in this scheme;

[0020] Figure 5 This is a schematic diagram showing the assembled variable-diameter linear rod held in the neutral position according to one embodiment of the present solution;

[0021] Figure 6 This is a schematic diagram showing the movement of the assembled variable-diameter linear rod towards the spring-loaded end in one embodiment of this solution;

[0022] Figure 7 This is a schematic diagram showing the movement of the assembled variable-diameter linear rod towards the stop spring end in one embodiment of this solution;

[0023] Among them, 1-compression spring, 2-rod, 21-first cylinder, 22-second cylinder, 23-third cylinder, 24-fourth cylinder, 25-stud, 26-pin hole, 3-center holding cylinder, 31-inner cavity, 32-internal threaded hole, 33-small hole, 34-wall hole, 4-card, 5-hollow round screw plug with hole on end face. Detailed Implementation

[0024] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0025] This application provides an embodiment of a center-holding mechanism: the embodiment includes a cylindrical helical compression spring 1, a variable-diameter linear rod 2, a center-holding cylinder 3, a spring fixing device, and a sealing spring device. The variable-diameter linear rod 2 can be a hollow rod or a solid rod, with its ends divided into a spring-passing end and a spring-stopping end. From the spring-stopping end to the spring-passing end, a first diameter, a second diameter, a third diameter, and a fourth diameter are sequentially provided. The first diameter is larger than the inner diameter of the compression spring 1, the second diameter is less than or equal to the inner diameter of the compression spring 1, the third diameter is smaller than the second diameter, and the fourth diameter is larger than the third diameter. In this embodiment, for ease of manufacturing, the variable-diameter linear rod 2 is a variable-diameter solid cylinder, and from the spring-stopping end to the spring-passing end, it is sequentially a first cylinder 21, a second cylinder 22, a third cylinder 23, and a fourth cylinder 24. The diameter of the first cylinder 21 is the first diameter, the diameter of the second cylinder 22 is the second diameter, the diameter of the third cylinder 23 is the third diameter, and the diameter of the fourth cylinder 24 is the fourth cylinder. The variable-diameter linear rod 2 can also be a square column or a continuously smooth variable-diameter rod, or other shapes, as long as it can hold and fix the compression spring 1. For ease of manufacturing, the fourth diameter is equal to the second diameter. That is, the diameter of the first cylinder 21 of the variable diameter linear rod 2 is smaller than the outer diameter of the compression spring 1, the diameter of the second cylinder 22 is slightly smaller than approximately equal to the inner diameter of the compression spring 1, the diameter of the third cylinder 23 is smaller than the diameter of the second cylinder 22, and the diameter of the fourth cylinder 24 is equal to the diameter of the second cylinder 22.

[0026] The variable-diameter linear rod 2 has external connection structures at both ends for connecting to other structural components such as crank arms and pull rods in the gas-insulated switchgear, and for receiving the input force. As an example, in this embodiment, the spring-loaded end is provided with a stud 25, and the spring-stopping end of the variable-diameter linear rod 2 is provided with a pin hole 26; the configuration can also be reversed.

[0027] When the compression spring 1 is pre-installed, it is compressed between the first diameter and the fourth diameter by the spring fixing device and the first diameter. In this embodiment, the spring fixing device on the other side uses a clip 4, which is an open circular plate with an opening to the center. The diameter of the clip 4 is greater than or equal to the outer diameter of the compression spring 1, the opening diameter is greater than or equal to the third diameter, and the opening diameter is smaller than the second diameter. The spring fixing device can also use other forms such as a snap ring, as long as one side can fix the compression spring 1 and the other side can be locked onto the step of the fourth cylinder 24 facing the compression spring 1.

[0028] During pre-installation, the compression spring 1 is inserted into the variable diameter linear rod 2, so that one end of the compression spring 1 abuts against the step at the junction of the first cylinder 21 and the second cylinder 22 of the variable diameter linear rod 2. The length of the compression spring 1 is greater than the sum of the second cylinder 21 and the third cylinder 23 of the variable diameter linear rod 2. Press the compression spring 1, align the opening of the card 4 with the third cylinder 23 of the variable diameter linear rod 2 and insert it. The inner diameter of the opening of the card 4 is slightly larger than approximately equal to the third cylinder 23, and the outer diameter is equal to the outer diameter of the compression spring 1. In this way, the compression spring 1 is pre-pressed onto the variable diameter linear rod 2 by the card 4.

[0029] The center-position retaining cylinder 3 has a straight cavity along its axis and is open at both ends, namely a rod end and a sealing spring end. The length of the straight cavity of the center-position retaining cylinder 3 is equal to the sum of the length of the compression spring 1 after pre-installation and the length of the spring fixing device. The rod end is fitted into the variable diameter straight rod 2, and the spring-stopping end is close to the end of the compression spring 1 away from the spring fixing device, so that the straight cavity of the center-position retaining cylinder 3 is fitted on the outside of the compression spring 1. The sealing spring end uses a sealing spring device to seal and fix the spring fixing device and the compression spring together in the straight cavity. The compression height of the compression spring 1 is less than the length of the straight cavity of the center-position retaining cylinder 3.

[0030] To facilitate manufacturing, the center-position retaining cylinder 3 in this embodiment is cylindrical in shape, but it can also be square, hexagonal, or other shapes. The sealing end of the center-position retaining cylinder 3 has an internally threaded hole 32, the minor diameter of which is larger than the outer diameter of the compression spring 1. The sealing device uses a hollow round screw plug 5 with a hole on the end face, which is fastened to the internally threaded hole 32. A small hole 33 is opened at the transmission rod end, the diameter of which is greater than or equal to the diameter of the first cylinder 21 of the variable diameter linear rod 2 but smaller than the outer diameter of the compression spring 1. The inner straight cavity of the center-position retaining cylinder 3 uses an inner circular cavity 31, but it can also be a square cylinder. Other shapes, such as hexagonal, can be used to fix the internal compression spring 1. In this embodiment, the diameter of the inner cavity 31 is slightly larger than and basically equal to the outer diameter of the compression spring 1, and the length of the inner cavity 31 is less than the sum of the second cylinder 22 and the third cylinder 23. This ensures that the plane of the card 4 can fit against the end face of the hollow round screw plug 5 with a hole, and the pre-assembled components do not wobble in the center-position retaining cylinder 3. The diameter of the inner cavity 31 is larger than the diameter of the card 4 and the length is larger than the length of the pre-compressed compression spring 1, ensuring that the outer circle of the card 4 fits into the inner cavity 31, eliminating the risk that the edge of the card 4 will get stuck on the plane of the inner cavity 31 when the variable diameter linear rod 2 moves to the right. The pre-assembled components are then put into the cylinder through the internal thread hole 32 of the cylinder, and then screwed into the hollow round screw plug 5 with a hole until it fits against one side of the card 4. At this time, the variable diameter linear rod 2 has no wobble in the center-position retaining cylinder 3 and is fixed in the center position. Other structures can also be used for the sealing spring device, such as setting a buckle on the inner side of the sealing spring end of the center-position retaining cylinder 3 and the mating surface of the sealing spring device, using the buckle to seal the card 4, and then pinching the buckle to pull out the sealing spring device when disassembling. The center-position retaining cylinder 3 also has a wall hole 34 in the middle for ventilation to avoid excessive local air pressure when the variable diameter linear rod 2 and the compression spring 1 move rapidly. In some specially designed cases, the third cylinder 23 can be omitted, and the diameter of the fourth cylinder 24 can be larger than that of the third cylinder 23 but smaller than the inner diameter of the compression spring 1.

[0031] In use, when the variable-diameter linear rod 2 is displaced to the left by force, the platform at the junction of the first cylinder 21 and the second cylinder 22 pushes the compression spring 1 until the compression spring 1 is tightly closed. When the force disappears, it returns to the middle position under the action of the compression spring 1. It should be noted that the length of the third cylinder 23 is greater than the maximum displacement distance plus the thickness of the card; otherwise, when moving to the left, the compression spring 1 will not be able to press to the tightly closed position. When the variable-diameter linear rod 2 is displaced to the right by force, the platform at the junction of the fourth cylinder 24 and the third cylinder 23 abuts against the card 4 and pushes the compression spring 1 until the compression spring 1 is tightly closed. When the force disappears, it returns to the middle position under the action of the compression spring 1, achieving the purpose of maintaining the middle position.

[0032] This embodiment only uses a portion of the variable diameter end of the variable diameter linear rod 2 as a spring fixing device for one side of the compression spring 1, and makes the other part of the variable diameter suitable for passing through the spring and fixing the other side of the compression spring 1. In fact, the variable diameter linear rod 2 can also be a regular constant diameter linear rod, with two pin holes through the constant diameter linear rod. Two cylindrical pins with a length greater than the inner diameter of the compression spring 1 are used as spring fixing devices to fix the compression spring 1, which is not in a compressed state, on the linear rod. The center position retaining cylinder 3 and the sealing spring device can have movement grooves along the in-and-out direction at the corresponding cylindrical pin in-and-out parts. When the linear rod moves to the left, the right cylindrical pin squeezes the right side of the compression spring 1, and the left side of the compression spring 1 is blocked by the sealing spring device. When the linear rod moves to the right, the left cylindrical pin squeezes the left side of the compression spring 1, and the right side of the compression spring 1 is blocked by the rod end.

[0033] Based on the same inventive concept, this application also discloses a gas-insulated switchgear, which uses the aforementioned neutral holding mechanism for interlocking of the internal structure, flexible connection of the connecting parts, and switch reset action of the transfer interruption circuit, etc.

[0034] The above description is only a preferred embodiment of the present solution, but the scope of protection claimed by the present solution is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and inventive concept of this application, should be included within the scope of protection of this application.

Claims

1. A center-holding mechanism, comprising a cylindrical helical compression spring (1), characterized in that: It also includes a straight rod, a center retaining cylinder (3), a spring fixing device and a sealing spring device. When the straight rod is pre-installed, it is fixed in a compressed state by the spring fixing device. The center retaining cylinder (3) has a straight cavity along the axis and is open at both ends, namely the rod end and the sealing spring end. The rod end is inserted into one end of the straight rod and closely attached to one end of the compression spring (1), so that the straight cavity of the center retaining cylinder (3) is fitted on the outside of the compression spring (1). The sealing spring end uses the sealing spring device to seal and fix the compression spring (1) in the straight cavity. The compression height of the compression spring (1) is less than the length of the straight cavity of the center retaining cylinder (3).

2. The centering mechanism according to claim 1, characterized in that: The linear rod uses a variable diameter linear rod (2). The end of the variable diameter linear rod (2) is divided into a spring-passing end and a spring-stopping end. From the spring-stopping end to the spring-passing end, a first diameter, a second diameter, a third diameter, and a fourth diameter are set in sequence. The first diameter is greater than the inner diameter of the compression spring (1), the second diameter is less than or equal to the inner diameter of the compression spring (1), the third diameter is less than the second diameter, and the fourth diameter is greater than the third diameter but less than the inner diameter of the compression spring (1). The first diameter serves as a spring fixing device on one side of the compression spring (1). When the compression spring (1) is pre-installed, it is compressed between the first diameter and the fourth diameter by the spring fixing device on the other side. The length of the linear cavity of the center retaining cylinder (3) is equal to the sum of the lengths of the compression spring (1) after pre-installation and the spring fixing device on the other side. The spring-passing end is fitted into the variable diameter linear rod (2). The spring-stopping end is close to the end of the compression spring (1) far from the spring fixing device. The spring-sealing end uses a spring-sealing device to seal and fix the spring fixing device and the compression spring together in the linear cavity.

3. The centering mechanism according to claim 2, characterized in that: The fourth diameter is equal to the second diameter.

4. The centering mechanism according to claim 3, characterized in that: The variable diameter straight rod (2) is a variable diameter solid cylinder, and from the stop spring end to the through spring end, it is a first cylinder (21), a second cylinder (22), a third cylinder (23), and a fourth cylinder (24) in sequence. The diameter of the first cylinder (21) is the first diameter, the diameter of the second cylinder (22) is the second diameter, the diameter of the third cylinder (23) is the third diameter, and the diameter of the fourth cylinder (24) is the fourth diameter.

5. The centering mechanism according to claim 2, characterized in that: The spring fixing device on the other side uses a card (4), which is an open circular plate with an opening to the center. The diameter of the card (4) is greater than or equal to the outer diameter of the compression spring (1), the opening diameter is greater than or equal to the third diameter, and the opening diameter is less than the second diameter.

6. The centering mechanism according to claim 2, characterized in that: The variable diameter straight rod (2) has a stud (25) at the spring end and a pin hole (26) at the spring stop end.

7. The centering mechanism according to claim 1, characterized in that: The central holding tube (3) is cylindrical in shape.

8. The centering mechanism according to claim 1, characterized in that: The sealing spring end of the middle retaining cylinder (3) is an internal threaded hole (32), and the sealing spring device uses a hollow round screw plug (5) with a hole on the end face. The hollow round screw plug (5) with a hole on the end face is fastened to the internal threaded hole (32).

9. The centering mechanism according to claim 1, characterized in that: The straight cavity inside the center-holding cylinder (3) uses an inner circular cavity (31).

10. A gas-insulated switchgear, characterized in that: Use the centering mechanism as described in any one of claims 1-9.

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