Operating mechanism of one-step isolating switch for railway overhead line system

Abstract

The utility model provides a kind of operating mechanism of one-step isolator for railway overhead line system, belong to isolator technical field, it includes box, motor is installed in box, worm that can rotate under the driving of motor and worm gear set matched with the worm, worm gear set is connected with rotating shaft, and output crank arm is connected after the one end of rotating shaft and projects box;The worm gear set includes cover plate, pedestal, rotating worm wheel and boss, the cover plate is fixed with pedestal, and pedestal and boss are respectively clamped in the both ends of rotating worm wheel axial direction, rotating worm wheel is engaged with worm, and boss is fixed with rotating shaft by key connection, the utility model solves the technical problem that internal transmission member damage caused by motor not timely power off in the operating mechanism of existing isolator, and improves the reliability of isolator.

Description

Technical Field

[0001] This utility model relates to the field of disconnecting switch technology, and in particular to an operating mechanism for a one-step disconnecting switch used in railway catenary. Background Technology

[0002] In railway power systems, disconnect switches are key electrical equipment, responsible for circuit switching and safety isolation. Their reliability directly affects the stability and safety of railway power supply, and the operating mechanism, as the core component of the disconnect switch, is of paramount importance.

[0003] Currently, disconnector operating mechanisms typically employ a motor-driven transmission structure. In this structure, the motor's output shaft is connected to a worm gear, which meshes with a worm wheel. The worm wheel is fixedly connected to the rotating shaft. When the motor rotates, power is transmitted through the worm gear to the worm wheel, which drives the rotating shaft to rotate synchronously. This, in turn, enables the disconnector to open or close via an output crank arm connected to the rotating shaft. This transmission structure relies on the rigid connection between the worm wheel and the rotating shaft, and the start and stop of the transmission process are controlled by the motor's start and stop. Under normal operating conditions, it can meet the basic opening and closing operation requirements.

[0004] However, the existing technology has at least the following drawbacks: Since the worm gear is fixedly connected to the shaft, if the motor is not de-energized in time after the switch is closed, the system will be overloaded due to inertia, causing the transmission components (such as worms and worm wheels) inside the operating mechanism to bear torque exceeding the design threshold, which reduces the reliability of the disconnecting switch and fails to meet the safety requirements of the railway system. Utility Model Content

[0005] This application provides an operating mechanism for a one-step disconnecting switch for railway overhead contact lines, which solves the technical problem of damage to internal transmission components caused by failure to disconnect the motor in a timely manner in existing disconnecting switch operating mechanisms, thereby improving the reliability of the disconnecting switch.

[0006] To solve the above-mentioned technical problems, this utility model adopts the following technical solution: an operating mechanism for a one-step disconnecting switch for railway contact networks, comprising a housing, a motor, a worm gear capable of rotating under the drive of the motor, and a worm wheel assembly cooperating with the worm gear, the worm wheel assembly being connected to a rotating shaft, one end of the rotating shaft extending out of the housing and connected to an output crank arm; the worm wheel assembly comprising a cover plate, a base, a rotating worm wheel, and a boss, the cover plate being fixed to the base, the base and the boss being clamped at both ends of the axial direction of the rotating worm wheel, the rotating worm wheel meshing with the worm, and the boss being fixed to the rotating shaft by a key connection.

[0007] When the motor drives the worm gear to rotate, the worm gear drives the rotating worm wheel to rotate. The rotating worm wheel drives the rotating shaft to rotate through the key connection between the boss and the shaft, and then the output crank arm transmits power to realize the opening and closing of the circuit breaker. Since the base and the boss are clamped at both ends of the axial direction of the rotating worm wheel, the boss can slip relative to the rotating worm wheel. Therefore, when the opening and closing of the circuit breaker is in place and the motor is not de-energized in time, the relative sliding between the rotating worm wheel and the boss can release the overload torque, cut off the power transmission path, and prevent the worm gear, worm wheel and other components from deforming due to overload, thereby improving the reliability and safety of the operating mechanism.

[0008] As a further improvement to the above solution, a limit switch is also installed inside the housing, and the trigger end of the limit switch is equipped with a roller head; a recessed part is provided on one side edge of the boss, and the recessed part is a groove opened along the circumference of the boss, and the roller head is located in the recessed part; the recessed part can maintain a gap with the roller head to avoid the limit switch being accidentally triggered; when the worm gear group rotates to the predetermined opening and closing angle, the edge of the recessed part of the boss gradually approaches and squeezes the roller head as it rotates, triggering the limit switch to cut off the motor power supply, thereby realizing the electrical limit control of the opening and closing position.

[0009] As a further improvement to the above solution, the boss is provided with a limit pin mounting hole, and a mechanical limit pin is installed in the limit pin mounting hole; when the limit switch fails to cut off the motor power supply in time due to electromagnetic delay or other reasons, the boss rotation is forcibly terminated by mechanical obstruction, which can quickly absorb the inertial kinetic energy of the motor and avoid deformation of the knife switch due to overshoot impact.

[0010] As a further improvement to the above scheme, a small gear is installed on the output shaft of the motor, and a large gear is installed on one end of the worm. The pitch circle diameter of the large gear is larger than that of the small gear, and the large gear meshes with the small gear. Thus, through the cooperation of the small gear and the large gear, a first-stage reduction can be formed, reducing the speed of the worm and amplifying the torque.

[0011] As a further improvement to the above solution, a hand crank is inserted into the end of the worm gear away from the large gear, and the hand crank extends out of one side of the housing; thus, when the electrical control system malfunctions or requires emergency maintenance, the worm gear can be driven to rotate by manually turning the hand crank, which in turn drives the worm gear assembly, the rotating shaft and the output crank arm to move, thereby realizing the opening and closing of the disconnecting switch.

[0012] As a further improvement to the above solution, the housing includes a transmission mounting plate through which the rotating shaft passes. Two bearing mounting plates are fixed on the transmission mounting plate, and ball bearings are installed inside each bearing mounting plate. The two ball bearings are nested outside the worm gear and are respectively close to both ends of the worm gear. The rolling friction of the balls reduces the transmission resistance, improves the transmission stability and the service life of the operating mechanism.

[0013] As a further improvement to the above solution, the transmission mounting plate is provided with an output shaft hole through which the rotating shaft passes, and a flanged composite bushing is installed in the output shaft hole; the flanged composite bushing can reduce friction and wear through its self-lubricating properties.

[0014] As a further improvement to the above solution, a skeleton oil seal is also provided at the point where the output shaft hole mates with the rotating shaft, and a sealing cover is installed on the outside of the skeleton oil seal; the cooperation between the skeleton oil seal and the sealing cover can prevent dust and moisture from entering the box from the outside, while preventing the leakage of lubricating oil inside the box.

[0015] As can be seen from the above technical solutions, this utility model has at least the following technical effects or advantages: In operation, this invention uses a motor to drive a worm gear to rotate, which in turn drives a rotating worm wheel to rotate. The rotating worm wheel, connected to a keyed boss on a rotating shaft, drives the shaft to rotate, which in turn transmits power through an output crank arm to achieve opening and closing of the circuit breaker. Since the base and the boss are clamped at both ends of the axial direction of the rotating worm wheel, the boss can slip relative to the rotating worm wheel. Therefore, when the circuit breaker is in position and the motor is not de-energized in time, the relative sliding between the rotating worm wheel and the boss can release the overload torque, cut off the power transmission path, and prevent the worm gear, worm wheel, and other components from deforming due to overload, thereby improving the reliability and safety of the operating mechanism. Attached Figure Description

[0016] To more clearly illustrate the technical solution of this utility model, the accompanying drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 for Figure 1 Sectional view along the middle AA; Figure 3 for Figure 1 A sectional view along the middle edge BB; Figure 4 This is a schematic diagram of the worm gear assembly in this utility model.

[0017] Explanation of reference numerals in the attached drawings: 1. Housing, 2. Motor, 3. Worm, 4. Worm gear assembly, 5. Shaft, 6. Output crank arm, 7. Cover plate, 8. Base, 9. Rotating worm gear, 10. Boss, 11. Limit switch, 12. Roller head, 13. Recessed part, 14. Limit pin mounting hole, 15. Pinion, 16. Gear, 17. Hand crank, 18. Transmission mounting plate, 19. Bearing fixing plate, 20. Ball bearing, 22. Flanged composite bushing, 23. Skeleton oil seal, 24. Sealing cover, 25. Limit baffle. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this patent, other embodiments obtained by those skilled in the art without creative effort are all within the scope of protection of this patent.

[0019] This utility model discloses an operating mechanism for a one-step disconnecting switch used in railway overhead contact lines, such as... Figures 1 to 4 As shown, it includes a housing 1, inside which a motor 2, a worm gear 3 that can rotate under the drive of the motor 2, and a worm wheel assembly 4 that cooperates with the worm gear 3 are installed. The worm wheel assembly 4 is connected to a rotating shaft 5, one end of which extends out of the housing 1 and is connected to an output crank arm 6. The worm wheel assembly 4 includes a cover plate 7, a base 8, a rotating worm wheel 9, and a boss 10. The cover plate 7 is fixed to the base 8, and the base 8 and the boss 10 are respectively clamped at both ends of the axial direction of the rotating worm wheel 9. The rotating worm wheel 9 meshes with the worm gear 3, and the boss 10 is fixed to the rotating shaft 5 by a key connection.

[0020] like Figure 1 , Figure 2 As shown, the motor 2 is horizontally fixed to the upper part of the housing 1, and the worm gear 3 is horizontally positioned below the motor 2, with its axial direction parallel to the length of the output shaft of the motor 2. The rotating worm wheel 9 is annular, with its inner ring sinking downwards at both ends to form a step. The base 8 and the boss 10 respectively fit against the two stepped surfaces of the rotating worm wheel 9. The cover plate 7, base 8, and boss 10 are also provided with through holes. After the cover plate 7, base 8, rotating worm wheel 9, and boss 10 are assembled, bolts pass through the through holes, and then the bolts are tightened with nuts to keep the boss 10 and base 8 clamping and fixing the rotating worm wheel 9. The boss 10 is connected to one end of the rotating shaft 5 via a flat key. The other end of the rotating shaft 5 extends out of the housing 1 and is fixed to the output crank arm 6. When the motor 2 drives the worm gear 3 to rotate, the worm gear 3 drives the rotating worm wheel 9 to rotate. The rotating worm wheel 9 drives the rotating shaft 5 to rotate via the boss 10, and then the power is transmitted by the output crank arm 6.

[0021] The clamping structure between the rotating worm gear 9, the boss 10, and the base 8 forms a rigid transmission chain, and the key connection between the rotating shaft 5 and the boss 10 ensures power synchronization. When the circuit breaker is in the open or close position, if the motor 2 is not de-energized in time, the rotating worm gear 9 can slide relative to the cover plate 7 and the base 8, releasing the overload torque through mechanical friction and preventing the worm 3, worm gear, and other components from deforming due to overload, thus achieving pure mechanical overload protection. For example, when the circuit breaker is in the open or close position and the rotating shaft 5 and the boss cannot continue to rotate, the rotating worm gear 9 will slip and cut off the power path, thereby preventing damage to the components inside the operating mechanism.

[0022] like Figure 1 As shown, the interior of the housing 1 also houses a rotary switch 26 and a limit switch 11. The trigger end of the limit switch 11 is equipped with a roller head 12. A recessed portion 13 is provided on one side edge of the boss 10, and the roller head 12 is located within the recessed portion 13. Specifically, the limit switch 11 is fixed to the inner wall of the housing 1. Its trigger end roller head 12 is cylindrical and extends into the recessed portion 13 on the outer circumference of the boss 10. The recessed portion 13 is a groove circumferentially formed on the edge of the boss 10, its function being to ensure a certain gap between the boss 10 and the roller head 12 during normal rotation, preventing the roller head 12 from being triggered. When the worm gear assembly 4 rotates with the worm 3 to the predetermined opening / closing angle, the edge of the recessed portion 13 of the boss 10 gradually approaches the roller head 12 until the outer contour of the boss 10 contacts the surface of the roller head 12 and applies pressure. At this time, the limit switch 11 is triggered, cutting off the power circuit of motor 2. Motor 2 stops rotating due to power failure, thereby realizing the electrical limit control of the opening and closing of the switch. For example, when the moving insulator swings to the side of the stationary insulator until it is fully closed with the main switch, the lower end face of the recessed part 13 of the boss 10 contacts the roller head 12, triggering the limit switch 11 to act, and the motor 2 stops rotating, ensuring accurate docking of the switch.

[0023] like Figure 2 , Figure 4As shown, the boss 10 has a limit pin mounting hole 14 for installing a mechanical limit pin. After the mechanical limit pin is fixedly installed with the boss, its axis is parallel to the axis of the rotating shaft 5 and extends outward along the axial direction of the boss 10. Rigid structural components such as a limit baffle 25 can be fixed on the inner wall of the housing 1 corresponding to the rotation trajectory of the mechanical limit pin. When the limit switch 11 fails to cut off the power to the motor 2 in time due to electromagnetic delay or other reasons, the inertial rotation of the motor 2 will be transmitted to the boss 10 through the worm gear 3 and worm wheel assembly 4, causing it to continue rotating. At this time, the mechanical limit pin rotates with the boss 10 and gradually approaches the limit baffle 25 inside the housing 1. When the rotation angle exceeds a certain angle beyond the predetermined opening and closing position, the end of the mechanical limit pin rigidly collides with the limit baffle 25, forcibly terminating the rotation of the boss 10 through mechanical obstruction. For example, after the motor 2 is de-energized, if the switch continues to swing, the mechanical limit pin, after contacting the limit baffle 25, can immediately reduce the speed of the boss 10 to zero, preventing the switch from impacting and deforming. Compared to structures that rely solely on electrical limits, this structure effectively absorbs the inertial kinetic energy of the motor by using rigid barriers, making it particularly suitable for railway systems where equipment reliability requirements are high.

[0024] In the above structure, the mechanical limit pin and the electrical limit pin can form a dual protection. Even if the electrical control fails, the rigid block of the mechanical limit pin can still stop the movement of the knife switch in time, reducing the risk of equipment damage caused by the inertial overshoot of the motor 2 and meeting the high reliability requirements of the railway system.

[0025] In the connection structure between motor 2 and worm gear 3, a pinion 15 is mounted on the output shaft of motor 2, and a large gear 16 is mounted on one end of worm gear 3. The pitch circle diameter of the large gear 16 is larger than that of the pinion 15, and the large gear 16 meshes with the pinion 15. The meshing of the pinion 15 and the large gear 16 forms a first-stage reduction. Thus, when motor 2 drives the pinion 15 to rotate, the speed of worm gear 3 can be reduced and the torque amplified through the large gear 16. Then, in conjunction with the two-stage reduction structure of worm gear and worm wheel, speed reduction and torque increase can be further achieved.

[0026] like Figure 1 , Figure 3As shown, a hand crank 17 is inserted into the end of the worm gear 3 away from the large gear 16, and the hand crank 17 extends out from one side of the housing 1. Specifically, a square hand crank hole is provided at the end of the worm gear 3 away from the large gear 16, and the insertion end of the hand crank 17 is a matching square protrusion. When manual operation is required, the directional protrusion of the hand crank 17 is inserted into the hand crank hole of the worm gear 3, and the hand crank 17 is rotated clockwise or counterclockwise by hand to drive the worm gear 3 to rotate, thereby driving the worm gear assembly 4, the rotating shaft 5, and the output crank arm 6 to move, realizing the opening and closing of the disconnecting switch. Thus, in the event of an electrical control system failure, when the motor 2 cannot work normally, or when emergency maintenance is required, rotating the hand crank 17 can serve as a backup operation to ensure that the disconnecting switch can still complete the opening and closing action. For example, when the railway contact network system experiences a sudden power outage or a motor control circuit failure, maintenance personnel can manually perform the opening operation through the hand crank 17 to quickly isolate the faulty section and shorten the power outage maintenance time.

[0027] On the other hand, such as Figure 1 , Figure 2 As shown, the housing 1 includes a transmission mounting plate 18 through which the rotating shaft 5 passes. Two bearing mounting plates 19 are provided on the surface of the transmission mounting plate 18, each housing a ball bearing 20. The two ball bearings 20 are nested outside the worm 3 and close to both ends of the worm 3. The inner ring of the ball bearing 20 is interference-fitted with the journal of the worm 3, and the outer ring of the ball bearing 20 is transition-fitted with the mounting hole of the bearing mounting plate 19. The two ball bearings 20 are located at both ends of the worm 3, forming a double-support structure, which can effectively withstand the radial load and a small amount of axial load generated by the worm 3 during transmission. For example, when the worm 3 drives the worm wheel assembly 4 to rotate, the rolling friction of the balls in the ball bearings 20 reduces the transmission resistance and limits the radial offset and axial movement of the worm 3, ensuring the meshing accuracy between the worm 3 and the rotating worm wheel 9.

[0028] In the above structure, the ball bearing 20 can reduce the axial movement and radial runout of the worm 3, ensure the stability of the meshing between the worm 3 and the rotating worm wheel 9, and reduce abnormal wear caused by assembly errors.

[0029] In addition, the transmission mounting plate 18 is provided with an output shaft hole through which the rotating shaft 5 passes, and a flanged composite bushing 22 is installed in the output shaft hole. The flanged composite bushing 22 includes a bushing body and a flanged structure. The flanged structure is located at the edge of one end of the bushing body and protrudes outward. When the flanged composite bushing 22 is installed in the output shaft hole of the transmission mounting plate 18, the flanged structure is in direct contact with the surface of the transmission mounting plate 18, which can form a physical barrier. The flanged composite bushing 22 can reduce friction and wear through its self-lubricating properties, and the flanged structure can achieve axial positioning of the rotating shaft 5.

[0030] Furthermore, a skeleton oil seal 23 is provided at one end of the output shaft hole where it mates with the rotating shaft 5, and a sealing cover 24 is installed on the outside of the skeleton oil seal 23. The sealing cover 24 is an annular plate and is fixed to the transmission mounting plate 18 with screws, thereby forming a double seal and improving the sealing effect. This structure can prevent dust and moisture from entering the housing 1 from the outside, while preventing the leakage of lubricating oil inside the housing 1.

[0031] In the description of this utility model, the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "vertical," and "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for describing this utility model and do not require that this utility model be constructed or operated in a specific orientation, and therefore should not be construed as limiting this utility model. The terms "connected" and "linked" in this utility model should be interpreted broadly. For example, they can refer to a connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0032] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in its embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.

Claims

1. An operating mechanism for a one-step disconnect switch for railway contact network, comprising a housing (1), a motor (2), a worm gear (3) capable of rotating under the drive of the motor (2), and a worm wheel assembly (4) cooperating with the worm gear (3), the worm wheel assembly (4) being connected to a rotating shaft (5), one end of the rotating shaft (5) extending out of the housing (1) and connected to an output crank arm (6); Its features are, The worm gear assembly (4) includes a cover plate (7), a base (8), a rotating worm gear (9), and a boss (10). The cover plate (7) is fixed to the base (8), and the base (8) and the boss (10) are respectively clamped at both ends of the axial direction of the rotating worm gear (9). The rotating worm gear (9) meshes with the worm (3), and the boss (10) is fixed to the rotating shaft (5) by a key connection.

2. The operating mechanism of a one-step disconnecting switch for railway catenary according to claim 1, characterized in that, Inside the housing (1), there is also a limit switch (11), and the trigger end of the limit switch (11) is provided with a roller head (12); a recessed part (13) is provided on one side edge of the boss (10), and the recessed part (13) is a groove opened along the circumference of the boss (10), and the roller head (12) is located in the recessed part (13).

3. The operating mechanism of a one-step disconnecting switch for railway catenary according to claim 2, characterized in that, The boss (10) is provided with a limit pin mounting hole (14), and a mechanical limit pin is installed in the limit pin mounting hole (14).

4. The operating mechanism of a one-step disconnecting switch for railway catenary according to claim 1, characterized in that, The output shaft of the motor (2) is equipped with a small gear (15), and a large gear (16) is installed at one end of the worm (3). The pitch circle diameter of the large gear (16) is larger than that of the small gear (15), and the large gear (16) meshes with the small gear (15).

5. The operating mechanism of a one-step disconnecting switch for railway catenary according to claim 4, characterized in that, A hand crank (17) is inserted at the end of the worm gear (3) away from the large gear (16), and the hand crank (17) extends out of one side of the housing (1).

6. The operating mechanism of a one-step disconnecting switch for railway catenary according to any one of claims 1 to 5, characterized in that, The housing (1) includes a transmission mounting plate (18) through which the rotating shaft (5) passes. Two bearing mounting plates (19) are fixed on the transmission mounting plate (18). Each bearing mounting plate (19) is equipped with a ball bearing (20). The two ball bearings (20) are nested outside the worm (3) and close to both ends of the worm (3).

7. The operating mechanism of a one-step disconnecting switch for railway catenary according to claim 6, characterized in that, The transmission mounting plate (18) is provided with an output shaft hole through which the rotating shaft (5) passes, and a flanged composite bushing (22) is installed in the output shaft hole.

8. The operating mechanism of a one-step disconnecting switch for railway catenary according to claim 7, characterized in that, A skeleton oil seal (23) is also provided at one end of the output shaft hole where it mates with the rotating shaft (5), and a sealing cover (24) is installed on the outside of the skeleton oil seal (23).

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