Low-wear piston system for a hydraulic mechanism of a circuit breaker

Abstract

The utility model relates to a low abrasion piston system for quick circuit breaker hydraulic mechanism, including piston cylinder and piston main part, the piston main part includes piston and piston rod, be equipped with dynamic seal on the piston, the opening of piston cylinder is fixed with end cover, and piston rod seal passes through end cover, the annular sealing groove of being located dynamic seal both sides is opened on the piston, the annular sealing groove is equipped with the guide wear -resisting ring, the outer ring of guide wear -resisting ring is opened and is equipped with a plurality of along the oil guide groove of axial penetration, the utility model rationally designs the structure and the layout of guide wear -resisting ring, realizes the support guide effect of bidirectional reciprocating motion, to guide instead of metal abrasion, improves the pressure -bearing capacity simultaneously, sets up low -pressure oil mouth filter device and foreign matter containing chamber, guarantees the cleanliness of system oil circuit, rationally designs end cover sealing structure, positive pressure and negative pressure bidirectional sealing, improves the sealing effect.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, specifically to a low-wear piston system for a hydraulic mechanism of a fast circuit breaker. Background Technology

[0002] High-voltage circuit breakers are crucial components of power transmission and transformation equipment. The operating mechanism is the power source for the circuit breaker, and all its movements are accomplished through the action of the operating mechanism. Hydraulic disc spring operating mechanisms, as a type of circuit breaker operating mechanism, are widely used due to their superior performance, including high integration, small size, large operating power, and stable performance. With the expansion of power system scale and the rapid growth of grid load, the level of short-circuit current in power systems is increasing year by year. The enormous short-circuit current has seriously threatened the safe operation of power systems. Therefore, the rapid clearing of fault currents places new demands on the operating speed and reliability of circuit breaker operating mechanisms.

[0003] For hydraulic disc spring operating mechanisms, since energy transmission is achieved through high-pressure oil, a high-pressure sealing system is necessary during operation. However, the failure of the high-pressure seal in a hydraulic disc spring mechanism leads to internal leakage, causing frequent pressure drops. This type of problem is currently a major issue with hydraulic disc spring operating mechanisms, which has a certain impact on the reliable operation of power transmission and transformation equipment.

[0004] Based on the working principle analysis of the hydraulic spring operating mechanism, regardless of whether the mechanism is in the open or closed state, as long as the hydraulic mechanism is in the energy storage state, internal leakage will occur when the seal of the energy storage piston is damaged and fails. Further analysis revealed that the cause of the damage to the dynamic seal of the energy storage piston is the presence of metallic impurities within the hydraulic system. As the hydraulic oil flows to the dynamic seal, the impurities become trapped in the dynamic seal area, scratching it during the reciprocating motion of the energy storage piston. Therefore, it is essential to change the traditional sealing structure of the energy storage piston system and provide a piston system with low wear, zero leakage, and high reliability. Utility Model Content

[0005] This utility model addresses the shortcomings of existing technologies by providing a low-wear piston system for the hydraulic mechanism of a fast circuit breaker. This piston system, used in the hydraulic disc spring operating mechanism of a fast circuit breaker, has good wear resistance, reliable sealing, and long service life, effectively solving the problems in the background technology.

[0006] This utility model is achieved through the following technical solution: a low-wear piston system for a hydraulic mechanism of a fast circuit breaker is provided, including a piston cylinder and a piston body. The piston body includes a piston and a piston rod. A dynamic seal is installed on the piston. An end cap is fixedly connected to the opening of the piston cylinder. The piston rod seal passes through the end cap. Annular sealing grooves are opened on the piston on both sides of the dynamic seal. A guide wear-resistant ring is installed in the annular sealing groove. Multiple axially penetrating oil guide grooves are opened on the outer ring of the guide wear-resistant ring.

[0007] In this design, the dynamic seal acts as a piston seal. The included guide wear ring provides precise guidance and support for the reciprocating piston, absorbs radial forces generated at any time, extends the service life of the piston cylinder, prevents metal-to-metal contact between the piston and cylinder, reduces friction, improves sealing performance, and prevents leakage. The oil guide groove design reduces the load on the dynamic seal and protects the sealing components. When the system experiences overpressure, the oil guide groove, in conjunction with the piston cylinder, can also release system pressure, providing over-pressure protection. The axially extending oil guide groove also guides the axial movement of the piston, reducing its rotational motion.

[0008] As an optimization, a combined seal is installed between the end cap and the piston rod. This combined seal includes a slip ring, the inner ring of which has an annular groove containing a star-shaped elastic rubber ring, and the outer ring of which has two O-rings. In this design, the star-shaped elastic rubber ring fits against the piston rod, the two O-rings fit against the inner hole of the end cap, and a grooved slip ring is sandwiched between the star-shaped and O-rings. When the piston body reciprocates, the elastic force of the elastic rubber rings on both sides simultaneously isolates both gas and oil media, achieving bidirectional sealing under positive and negative pressure, thus improving the sealing performance of the slip ring.

[0009] As an optimization, a dust seal is installed between the end cap and the piston rod, with the dust seal located on the outside of the combined seal. The dust seal in this design prevents dust from entering the combined seal, thereby improving its service life and sealing performance.

[0010] As an optimization, the piston cylinder is arranged laterally, and a foreign matter receiving cavity is formed on the bottom surface of the inner wall of the piston cylinder. In this design, when the system is located at the bottom of the hydraulic mechanism, the foreign matter receiving cavity can capture impurities such as metal particles generated during wear, preventing these particles from flowing with the oil circuit to other sealing positions in the hydraulic mechanism and thus preventing damage to the sealing performance.

[0011] As an optimization, a low-pressure oil port is provided on the piston cylinder, and a cap-shaped metal filter screen is installed inside the low-pressure oil port. The cap-shaped metal filter screen in this solution serves to filter the oil, preventing metal particles or other foreign objects from entering the piston system when they appear in the oil circuit connected to the low-pressure oil.

[0012] As an optimization, the end cap is connected to the piston cylinder flange by bolts, thereby achieving a detachable and fixed connection of the end cap.

[0013] As an optimization, the piston body is coated with tungsten carbide to improve wear resistance.

[0014] As an optimization, the end cap is provided with a protrusion that inserts into the piston cylinder, and a sealing ring is installed between the outer ring of the protrusion and the piston cylinder. This improves the sealing performance of the end cap.

[0015] As an optimization, the guide wear ring is made of polytetrafluoroethylene with added copper powder. This gives the guide wear ring excellent wear resistance.

[0016] The beneficial effects of this utility model are as follows: (1) Reasonably design the structure and layout of the guide wear ring to realize the supporting and guiding role of bidirectional reciprocating motion, replace metal wear with guidance, and improve the pressure bearing capacity.

[0017] (2) Design the piston structure reasonably to improve the piston wear resistance.

[0018] (3) Design the structure of the piston cylinder reasonably, set up a low-pressure oil port filter device and a foreign matter containment cavity to ensure the cleanliness of the system oil circuit.

[0019] (4) The end cap sealing structure is reasonably designed to achieve bidirectional sealing under positive and negative pressure, thereby improving the sealing effect.

[0020] (5) The fitting clearance between the piston and cylinder is reasonably designed to reduce piston wear and effectively prevent impurities from entering the sealing part. Therefore, this utility model has the advantages of good wear resistance, reliable sealing and long service life. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the end structure of this utility model; Figure 2 This utility model Figure 1 Sectional view of plane AA; Figure 3 This is an enlarged cross-sectional view of the combined sealing component of this utility model; Figure 4 This is a cross-sectional schematic diagram of the guide wear-resistant ring of this utility model; Figure 5 This utility model Figure 4 Enlarged view of section B in the middle; As shown in the figure: 1. Piston body, 2. Annular sealing groove, 3. Dynamic seal, 4. Guide wear-resistant ring, 5. Oil guide groove, 6. Piston cylinder, 7. Cap-shaped metal filter screen, 8. Sealing cylinder liner, 9. Foreign matter receiving cavity, 10. End cap, 11. Connecting bolt, 12. Star-shaped elastic rubber ring, 13. O-ring elastic rubber ring, 14. Slip ring. Detailed Implementation

[0022] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to describe the solution.

[0023] like Figures 1-5 As shown, this utility model discloses a low-wear piston system for a hydraulic mechanism of a fast circuit breaker, comprising a piston cylinder 6 and a piston body 1. The piston body 1 includes a piston and a piston rod, and is coated with tungsten carbide to improve wear resistance. In this embodiment, the piston and piston rod are integrally formed. An end cap 11 is fixedly connected to the opening of the piston cylinder 6. In this embodiment, the end cap 11 is bolted to the flange of the piston cylinder 6, thereby forming a sealed piston chamber inside the piston cylinder 6. To improve the sealing performance between the end cap 11 and the piston cylinder 6, a protrusion is provided on the end cap 11 that inserts into the piston cylinder 6, and a sealing ring is installed between the outer ring of the protrusion and the piston cylinder 6.

[0024] The piston cylinder 6 has a low-pressure oil port and a high-pressure oil port. The low-pressure oil port is located in the rod chamber of the piston cylinder 6, and the high-pressure oil port is located in the rodless chamber of the piston cylinder 6. A sealing cylinder sleeve 8 is installed on the low-pressure oil port, and a cap-shaped metal filter screen 7 is installed inside the sealing cylinder sleeve 8. It serves to filter the oil and prevent metal particles or other foreign objects from entering the piston system when they appear in the oil passage connected to the low-pressure oil.

[0025] The piston rod seal passes through the end cap 11. To improve the sealing performance at the piston rod passage point, a combined seal is installed between the end cap 11 and the piston rod. An annular groove is formed in the inner hole of the end cap 11, and the combined seal is installed in the annular groove. Figure 3 As shown, the combined sealing component includes a slip ring 14 made of polytetrafluoroethylene (PTFE). The inner ring of the slip ring 14 is fitted to the piston rod, and an annular groove is formed in the inner ring of the slip ring 14. A star-shaped elastic rubber ring 12 is installed in the annular groove, and two O-rings 13 are installed on the outer ring of the slip ring 14. The star-shaped elastic rubber ring is fitted to the piston rod, and the two O-rings are fitted to the inner hole of the end cap. A grooved slip ring is sandwiched between the star-shaped elastic rubber ring and the two O-rings. When the piston body reciprocates, under the elastic force of the elastic rubber rings on both sides, both gas and oil media can be isolated simultaneously, achieving bidirectional sealing under positive and negative pressure, and improving the sealing performance of the slip ring.

[0026] To prevent dust from affecting the sealing effect of the combined seal, a dustproof ring is installed between the end cap 11 and the piston rod, and the dustproof ring is located on the outside of the combined seal.

[0027] The piston is equipped with a dynamic seal 3. The dynamic seal is a prior art technology and is generally implemented using a sealing ring. It is a sealing element on the piston that achieves a sealing effect during movement. The piston has annular sealing grooves 2 located on both sides of the dynamic seal 3. The annular sealing grooves 2 are equipped with guide wear-resistant rings 4. The guide wear-resistant rings 4 are made of polytetrafluoroethylene with added copper powder.

[0028] The outer ring of the guide wear ring 4 is in contact with the inner wall of the piston cylinder 6, such as... Figure 4 , 5 As shown, the outer ring of the guide wear-resistant ring 4 has multiple axially penetrating oil guide grooves 5. In this embodiment, two oil guide grooves 5 are provided and evenly distributed circumferentially. The guide wear-resistant ring provides precise guidance and support for the reciprocating piston and can absorb the radial force generated at any time, extending the service life of the piston cylinder. At the same time, it can prevent metal-to-metal contact between the piston and the piston cylinder, reduce friction, improve the sealing effect, and avoid leakage. The design of the oil guide grooves can reduce the bearing pressure of the dynamic seal and protect the sealing components. When the system experiences overpressure, the oil guide grooves cooperate with the piston cylinder to release system pressure, playing a role in over-position protection. The axially penetrating oil guide grooves can also guide the axial movement of the piston, reducing the rotational movement of the piston.

[0029] The piston cylinder 6 is arranged laterally, and a foreign matter receiving cavity 9 is formed on the bottom surface of the inner wall of the piston cylinder 6. The cavity structure of the foreign matter receiving cavity 9 is a grid type, that is, it is composed of multiple rectangular groove arrays. When the system is located at the bottom of the hydraulic mechanism, it can capture impurities such as metal particles generated during the wear process, and prevent metal particles from flowing with the oil circuit to other sealing positions of the hydraulic mechanism and damaging the sealing performance.

[0030] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A low-wear piston system for a hydraulic mechanism of a fast circuit breaker, comprising a piston cylinder (6) and a piston body (1), the piston body (1) comprising a piston and a piston rod, the piston being fitted with a dynamic seal (3), characterized in that: An end cap (11) is fixedly connected to the opening of the piston cylinder (6), and the piston rod seal passes through the end cap (11). The piston has an annular sealing groove (2) located on both sides of the dynamic seal (3). A guide wear-resistant ring (4) is installed in the annular sealing groove (2). The outer ring of the guide wear-resistant ring (4) has multiple axially penetrating oil guide grooves (5).

2. The low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: A combined seal is installed between the end cap (11) and the piston rod. The combined seal includes a slip ring (14). The inner ring of the slip ring (14) has an annular groove, and a star-shaped elastic rubber ring (12) is installed in the annular groove. The outer ring of the slip ring (14) is equipped with two O-rings (13).

3. The low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: A dust seal is installed between the end cap (11) and the piston rod, and the dust seal is located on the outside of the combined seal.

4. The low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: The piston cylinder (6) is arranged horizontally, and a foreign object receiving cavity (9) is opened on the bottom surface of the inner wall of the piston cylinder (6).

5. A low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: The piston cylinder (6) has a low-pressure oil port, and a cap-shaped metal filter screen (7) is installed inside the low-pressure oil port.

6. A low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: The end cap (11) is connected to the flange of the piston cylinder (6) by bolts.

7. A low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: The piston body (1) is coated with tungsten carbide.

8. A low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: The end cap (11) is provided with a protrusion that is inserted into the piston cylinder (6), and a sealing ring is installed between the outer ring of the protrusion and the piston cylinder (6).

9. A low-wear piston system for a fast-acting circuit breaker hydraulic mechanism according to claim 1, characterized in that: The guide wear ring (4) is made of polytetrafluoroethylene with added copper powder.

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