Insulating pull rod with ease of adjusting spring pre-pressure

Abstract

The application discloses an insulating pull rod which is convenient to adjust spring pre-pressure, and comprises an insulating rod body, an upper pull rod and a lower pull rod, a spring seat made of metal material is fixed in the insulating rod body, and a spring is installed in the inner cavity of the spring seat; a circular ring-shaped blocking piece is further arranged, the circular ring-shaped blocking piece is screwed on the top of the spring seat through external threads; an upper pull rod connecting piece is further arranged, the upper part of the upper pull rod connecting piece is a cylindrical connecting head, the cylindrical connecting head passes through the central hollow hole of the circular ring-shaped blocking piece upwards; the middle part of the upper pull rod connecting piece is formed with a circular ring-shaped convex rib; the circular ring-shaped blocking piece is provided with 6-12 positioning round holes, the side wall of the spring seat is provided with a plurality of vertical positioning screw holes, and a positioning bolt is further arranged, the shank of the positioning bolt passes through the positioning round hole of the circular ring-shaped blocking piece and is screwed into the positioning screw hole of the side wall of the spring seat. The application can conveniently adjust the spring pre-pressure for multiple times, and the locking cover will not be axially displaced relative to the spring seat after the adjustment is completed and the reassembly is finished.

Description

Technical Field

[0001] This invention belongs to the technical field of electrical equipment, and in particular relates to an insulating pull rod that facilitates adjustment of spring preload. Background Technology

[0002] Vacuum circuit breakers in electrical systems achieve opening and closing operations by the contact or separation of the moving and stationary contacts inside the vacuum bulb. The moving contact and its drive mechanism of the vacuum circuit breaker are connected by an insulating rod. The insulating rod includes an insulating rod body, an upper rod, and a lower rod. The insulating rod body is made of insulating material, while the upper and lower rods are made of metal. The upper end of the lower rod connects to the lower end of the insulating rod body. Of the upper and lower rods, one connects to the moving contact, and the other connects to the drive mechanism.

[0003] In order to provide a buffer when the moving and stationary contacts close and to ensure sufficient contact pressure after the moving and stationary contacts make contact, a spring with a pre-compression amount must be provided between the upper and lower pull rods of the insulating pull rod, and the spring pre-compression must reach a set range value, such as 1600±100N, 1800±100N, or 2000±100N, etc.

[0004] The aforementioned spring is installed inside a spring seat made of metal material, which is fixedly clamped in the insulating rod body. The side wall of the spring seat is cylindrical, and the opening of the spring seat faces upward. A locking cover is also screwed onto the opening of the spring seat using threads. The upper end of the spring touches the locking cover, and the lower end of the spring touches the bottom of the spring seat. Therefore, the vertical distance between the locking cover and the bottom of the spring seat determines the pre-compression amount (pre-compression length) of the spring.

[0005] Insulating rods undergo thousands of opening and closing mechanical actions during use. To ensure the spring's preload length remains constant, it's necessary to prevent the lock cover from axially shifting after continuous pressure and multiple opening and closing actions. However, since the insulating rod body is a standard injection-molded part, it's difficult to provide a positioning function to prevent the lock cover from shifting (rotating). Similarly, the spring seat is difficult to provide a positioning function to prevent the lock cover from shifting (rotating). Therefore, in traditional technology, the lock cover and spring seat are typically riveted together after the spring's preload length has been adjusted. This technical solution has the following shortcomings: While riveting the lock cover and spring seat together ensures their relative positions and the spring's preload length remain unchanged, after a period of use, the spring's elastic coefficient changes due to metal fatigue, leading to a change in the actual preload, deviating from the set range, and being difficult to adjust back. If adjustment is necessary, it generally requires damaging the lock cover threads and replacing the lock cover, which may also damage the spring seat. Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned disadvantages and provide an insulating pull rod that is easy to adjust the spring preload. It can easily adjust the spring preload multiple times, and after adjustment and reassembly, the lock cover will not shift axially relative to the spring seat.

[0007] The purpose can be achieved by the following scheme: an insulating rod that is easy to adjust the spring preload, including an insulating rod body, an upper rod, and a lower rod. The insulating rod body is made of insulating material, and the upper rod and lower rod are made of metal. The upper end of the lower rod is connected to the lower end of the insulating rod body. A spring seat made of metal material is fixed in the insulating rod body. The opening of the spring seat faces upward. The side wall of the spring seat is cylindrical. A spring is installed in the inner cavity of the spring seat. The lower end of the spring touches the bottom of the spring seat. Its main features are that the wall thickness of the top section of the spring seat sidewall is less than that of other sections of the spring seat sidewall, the inner diameter of the top section of the spring seat sidewall is greater than that of other sections of the spring seat sidewall, and a circular horizontal stepped surface is formed at the junction of the top section of the spring seat sidewall and other sections of the spring seat sidewall; the top section of the spring seat sidewall has an internal thread; and a circular sealing member is also provided, with an external thread formed on the outer circumferential surface of the circular sealing member, which is screwed onto the top of the spring seat using the external thread, and a central hollow hole is formed in the center of the circular sealing member. It is also provided with an upper pull rod connector, the upper part of which is a cylindrical connector, which passes upward through the central hollow hole of the annular sealing part; a blind hole with internal thread is opened in the center of the cylindrical connector, and the lower end of the upper pull rod is screwed into the blind hole; A circular rib is formed in the middle of the upper pull rod connector. The upper end of the spring presses against the lower end face of the circular rib, and the upper end face of the circular rib presses against the lower end face of the circular sealing member. The annular sealing component has 6 to 12 positioning holes, and each positioning hole is evenly distributed along the circumference of the annular sealing component. The side wall of the spring seat has multiple vertical positioning screw holes. The opening of the positioning screw holes is located on the horizontal stepped surface of the spring seat. Each positioning screw hole is evenly distributed along the circumference of the side wall of the spring seat. The number of positioning screw holes is the same as the number of positioning round holes. The distance between the positioning screw holes and the central axis of the side wall of the spring seat is equivalent to the distance between the positioning round holes and the central axis of the annular sealing part. It is also equipped with a positioning bolt, which includes a screw and a nut. The screw of the positioning bolt passes through the positioning hole of the annular sealing part and is screwed into the positioning screw hole on the side wall of the spring seat.

[0008] The nut of the positioning bolt has an internal hexagonal hole, each positioning bolt is equipped with a cotter pin, and the positioning bolt also has a pin hole for the cotter pin to pass through, with the axis of the pin hole perpendicular to the axis of the positioning bolt. It also includes a bolt interlocking component made of metal material, which is composed of a first interlocking plate, a second interlocking plate, a third interlocking plate, a fourth interlocking plate, a fifth interlocking plate, a sixth interlocking plate, and a seventh interlocking plate connected vertically in sequence to form a whole; The fourth interlocking piece has two screw holes for the positioning bolt screws to pass through. The distance between the two screw holes is equal to the distance between any two adjacent positioning holes on the annular sealing piece. The diameter of each screw hole is larger than the diameter of the positioning bolt screw but smaller than the diameter of the positioning bolt nut. The second and sixth chain pieces are located on the same plane and are parallel to the fourth chain piece. The first, third, fifth, and seventh chain pieces are perpendicular to the fourth chain piece. The first chain piece is parallel to the third chain piece, and the fifth chain piece is parallel to the seventh chain piece. The second and sixth interlocking plates are respectively provided with nut holes for the positioning bolt nuts to pass through, and the first, third, fifth, and seventh interlocking plates are respectively provided with locking holes for the cotter pins to pass through. The positioning bolts are paired and fitted together. In each pair of positioning bolts, the shank of the first positioning bolt passes through the first shank hole of the fourth interlocking plate, the shank of the second positioning bolt passes through the second shank hole of the fourth interlocking plate, the nut of the first positioning bolt passes through the nut hole of the second interlocking plate, and the nut of the second positioning bolt passes through the nut hole of the sixth interlocking plate. The nuts of the two positioning bolts press the fourth interlocking plate onto the upper end face of the annular sealing member. The cotter pin corresponding to the first positioning bolt passes through the locking hole of the first interlocking plate, the pin hole of the first positioning bolt, and the locking hole of the third interlocking plate. The cotter pin corresponding to the second positioning bolt passes through the locking hole of the fifth interlocking plate, the pin hole of the second positioning bolt, and the locking hole of the seventh interlocking plate.

[0009] The planes containing the first and seventh chain pieces form an angle greater than 60 degrees.

[0010] The present invention has the following advantages and effects: I. This invention allows for adjustment of the spring preload during use after leaving the factory. When adjustment is needed, simply remove the cotter pin, unscrew each set of positioning bolts from the annular sealing component, and temporarily remove the bolt interlocking component. Then, the annular sealing component can be rotated to adjust the spring preload. After adjustment, all the components can be reinstalled intact without any damage. Moreover, the adjustment accuracy is high; the adjustment accuracy of the spring preload length can be 1 / 6 to 1 / 12 of the external thread pitch of the annular sealing component.

[0011] II. During normal use, this invention ensures that the lock cover will not shift axially relative to the spring seat after continuous pressure and multiple opening and closing operations, and the positioning bolts will not loosen. The relative position of the lock cover and the spring seat is locked by the positioning bolts, which are in turn locked to the lock cover by a bolt interlock and a cotter pin (meaning the positioning bolts cannot loosen relative to the lock cover's rotation). The bolt interlock and the lock cover are locked by two positioning bolts (two points defining a straight line). This forms a closed-loop interlock. The two positioning bolts in each group prevent the bolt interlock from rotating, and the bolt interlock, in turn, combined with the cotter pin, prevents each positioning bolt from rotating. The positioning bolts also prevent the annular sealing component from rotating, thus ensuring that the annular sealing component will not shift during the opening and closing mechanical operation. Furthermore, both the positioning bolts and the bolt interlock can be disassembled when needed, allowing users to conveniently adjust the spring preload multiple times during use.

[0012] Third, bolted interlocking parts can be made from a single metal plate by bending, so they are easy to process and have low cost. Attached Figure Description

[0013] Figure 1 This is a three-dimensional structural schematic diagram of a specific embodiment of the present invention.

[0014] Figure 2 yes Figure 1 A cross-sectional structural schematic diagram of the embodiment shown.

[0015] Figure 3 yes Figure 1 The above-view structural diagram of the embodiment is shown.

[0016] Figure 4 yes Figure 2 The exploded structural diagram of the embodiment shown (the insulating rod body, upper pull rod, and lower pull rod are omitted).

[0017] Figure 5 yes Figure 1 The exploded structural diagram of the embodiment shown (the upper and lower pull rods are omitted).

[0018] Figure 6 yes Figure 4 A schematic diagram of the spring seat in the diagram.

[0019] Figure 7 yes Figure 4 A schematic diagram of the upper pull rod connector.

[0020] Figure 8 yes Figure 4 A schematic diagram of the structure of the annular sealing component.

[0021] Figure 9This is a three-dimensional structural diagram of the circular sealing component.

[0022] Figure 10 This is a three-dimensional structural diagram of the positioning bolt.

[0023] Figure 11 It is a three-dimensional structural diagram of the assembled positioning bolts, bolt interlocking parts, and cotter pins.

[0024] Figure 12 yes Figure 11 An exploded view of the structure shown.

[0025] Figure 13 This is a three-dimensional structural diagram of a bolted interlocking component.

[0026] Figure 14 This is a top view of the bolted interlocking mechanism.

[0027] Figure 15 yes Figure 14 Schematic diagram of the cross-sectional structure of GG.

[0028] Figure 16 yes Figure 14 Schematic diagram of the cross-sectional structure of HH.

[0029] Figure 17 yes Figure 15 Schematic diagram of the cross-sectional structure of the PP. Detailed Implementation

[0030] Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 An insulating pull rod for easy adjustment of spring preload is shown, comprising an insulating rod body 10, an upper pull rod 11, and a lower pull rod 12. The insulating rod body 10 is made of insulating material, while the upper pull rod 11 and the lower pull rod 12 are made of metal. The upper end of the lower pull rod 12 is connected to the lower end of the insulating rod body 10. A spring seat 3 made of metal is fixed in the insulating rod body 10. The opening of the spring seat 3 faces upward, and the side wall 31 of the spring seat is cylindrical. A spring 32 is installed in the inner cavity 30 of the spring seat, and the lower end of the spring 32 presses against the bottom 310 of the spring seat.

[0031] Figure 6 As shown, the top section of the spring seat sidewall 31 ( Figure 6 The wall thickness of the AC / BD section is less than the wall thickness of the other sections of the spring seat sidewall 31. The inner diameter of the top section of the spring seat sidewall (equivalent to...) Figure 6 The length of AB or CD is greater than the inner diameter of the other sections of the spring seat sidewall (equivalent to...). Figure 6The junction of the top section of the spring seat sidewall and other sections of the spring seat sidewall (equivalent to the length of EF) forms a circular horizontal stepped surface 34. Figure 6 (CE surface / FD surface); the top section of the spring seat sidewall 31 has an internal thread. Figure 2 , Figure 8 , Figure 9 , Figure 4 , Figure 5 As shown, an annular sealing member 4 is also provided. The outer circumferential surface of the annular sealing member 4 is formed with an external thread. The external thread engages with the internal thread of the top section of the side wall 31 of the spring seat. The annular sealing member 4 is screwed onto the top of the spring seat 3 using the external thread. A central hollow hole 40 is formed in the center of the annular sealing member 4.

[0032] Figure 2 , Figure 8 , Figure 9 , Figure 4 , Figure 5 , Figure 7 As shown, an upper pull rod connector 2 is also provided. The upper part of the upper pull rod connector 2 is a cylindrical connector 21. The cylindrical connector 21 passes upward through the central hollow hole 40 of the annular sealing member. A blind hole 20 with internal threads is opened in the center of the cylindrical connector. The lower end of the upper pull rod 11 is screwed into the blind hole 20. An annular rib 22 is formed in the middle of the upper pull rod connector 2. The upper end of the spring 32 touches the lower end face of the annular rib 22. The upper end face of the annular rib 22 touches the lower end face of the annular sealing member 4. The annular sealing member 4 has eight positioning holes 41. Each positioning hole 41 is evenly distributed along the circumference of the annular sealing member 4.

[0033] Figure 6 , Figure 5 As shown, the side wall 31 of the spring seat has multiple vertical positioning screw holes 33, and the openings of the positioning screw holes 33 are located on the horizontal stepped surface 34 of the spring seat (equivalent to...). Figure 6 (CE surface / FD surface), each positioning screw hole 33 is evenly distributed circumferentially along the side wall 31 of the spring seat. The number of positioning screw holes 33 is the same as the number of positioning round holes 41. The distance between the positioning screw holes 33 and the central axis of the side wall 31 of the spring seat is equivalent to the distance between the positioning round holes 41 and the central axis of the annular sealing part 4.

[0034] Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 11 , Figure 12As shown, a positioning bolt 5 is also provided, which includes a screw 51 and a nut 52. The screw 51 of the positioning bolt 5 passes through the positioning hole 41 of the annular sealing member and is screwed into the positioning screw hole 33 of the side wall 31 of the spring seat. The nut 52 of the positioning bolt 5 has an internal hexagonal hole 50. Each positioning bolt 5 is equipped with a cotter pin 7. The positioning bolt 5 also has a pin hole 53 for the cotter pin 7 to pass through. The pin holes 53 are arranged in a cross shape. The axis of the pin holes 53 is perpendicular to the axis of the positioning bolt 5, that is, the axis of the pin holes 53 is in the horizontal direction. A bolt interlocking member 6 made of metal material is also provided.

[0035] Figure 11 , Figure 12 , Figure 13 , Figure 14 , Figure 15 , Figure 16 , Figure 17As shown, the bolt interlocking component 6 is formed by vertically connecting the first interlocking piece 61, the second interlocking piece 62, the third interlocking piece 63, the fourth interlocking piece 64, the fifth interlocking piece 65, the sixth interlocking piece 66, and the seventh interlocking piece 67 in sequence. The fourth interlocking piece 64 is arc-shaped and has two screw holes (screw hole 601 and screw hole 602) for the positioning bolt screw 51 to pass through. The distance between the two screw holes (screw hole 601 and screw hole 602) is equal to the distance between every two adjacent positioning circular holes 41 on the annular sealing component 4. The distance between the bolt and the bolt head; the diameter of each bolt hole is larger than the diameter of the positioning bolt bolt 51 but smaller than the diameter of the positioning bolt nut 52; the second interlocking plate 62 and the sixth interlocking plate 66 are located on the same plane and are both parallel to the fourth interlocking plate 64, the first interlocking plate 61, the third interlocking plate 63, the fifth interlocking plate 65, and the seventh interlocking plate 67 are perpendicular to the fourth interlocking plate 64, the first interlocking plate 61 is parallel to the third interlocking plate 63, and the fifth interlocking plate 65 is parallel to the seventh interlocking plate 67; the second interlocking plate 62 has a nut hole 681 for the positioning bolt nut 52 to pass through. The sixth interlocking plate 66 has a nut hole 682 for the positioning bolt nut 52 to pass through. The first interlocking plate 61, the third interlocking plate 63, the fifth interlocking plate 65, and the seventh interlocking plate 67 each have a locking hole 69 for the cotter pin 7 to pass through. The positioning bolts 5 are paired. In each pair of positioning bolts 5, the screw 51 of the first positioning bolt 5 passes through the first screw hole 601 of the fourth interlocking plate 64, the screw 51 of the second positioning bolt passes through the second screw hole 602 of the fourth interlocking plate, and the nut 52 of the first positioning bolt... 2. The nut 52 of the second positioning bolt passes through the nut hole 681 of the second interlocking piece, and the nut 52 of the second positioning bolt passes through the nut hole 682 of the sixth interlocking piece. The nuts 52 of the two positioning bolts press the fourth interlocking piece 64 onto the upper end face of the annular sealing member 4. The cotter pin 7 corresponding to the first positioning bolt 5 passes through the locking hole 69 of the first interlocking piece, the pin hole 53 of the first positioning bolt, and the locking hole 69 of the third interlocking piece. The cotter pin 7 corresponding to the second positioning bolt 5 passes through the locking hole 69 of the fifth interlocking piece, the pin hole 53 of the second positioning bolt, and the locking hole 69 of the seventh interlocking piece. The plane where the first interlocking piece 61 is located (in...) Figure 17 The plane represented by the KQ line and the plane containing the seventh chain piece 67 (in) Figure 17 (The two lines are represented by the straight line MN) and form an angle of 75 degrees.

[0036] The operating principle of the above embodiment is as follows: When it is necessary to adjust the preload of spring 32, simply unscrew the upper pull rod 11 from the upper pull rod connector 2, remove the cotter pin 7, unscrew each set of positioning bolts 5 from the annular sealing member 4, and temporarily remove the bolt interlock 6. Use the pneumatic mechanism to temporarily press the cylindrical connector 21. In this way, the annular sealing member 4 can be rotated to adjust the spring preload. The minimum rotation angle is 45 degrees each time, and the adjustment accuracy of the spring preload length can be 1 / 8 of the external thread pitch of the annular sealing member. After adjustment, the pneumatic mechanism is removed, and the aforementioned bolt interlocking parts 6, each set of positioning bolts 5, and cotter pins 7 are reinstalled. After reinstallation, the two positioning bolts 5 in each set lock the bolt interlocking parts 6 so that they cannot rotate (i.e., they cannot rotate around any positioning bolt 5). Conversely, the bolt interlocking parts 6 lock each positioning bolt 5 so that it cannot rotate on its own through the cotter pins 7. The positioning bolts 5 lock the annular sealing parts 4 so that it cannot rotate on its own. Therefore, it is ensured that the annular sealing parts 4 will not move during the opening and closing mechanical operation, that is, the adjusted spring preload can be kept unchanged.

[0037] In the above embodiments, the number of positioning holes of the annular sealing component can be changed to 6 or 12, and the number of positioning screw holes 33 on the side wall of the spring seat corresponds to the number of positioning holes 41.

[0038] The angle formed by the planes containing the first interlocking piece 61 and the seventh interlocking piece 67 can be changed to 65 degrees, or 90 degrees, etc.

Claims

1. An insulating pull rod for easy adjustment of spring preload, comprising an insulating rod body, an upper pull rod, and a lower pull rod, wherein the insulating rod body is made of insulating material, the upper and lower pull rods are made of metal, the upper end of the lower pull rod is connected to the lower end of the insulating rod body, a spring seat made of metal material is fixed in the insulating rod body, the spring seat opening faces upward, the side wall of the spring seat is cylindrical, a spring is installed in the inner cavity of the spring seat, and the lower end of the spring touches the bottom of the spring seat; characterized in that, The wall thickness of the top section of the spring seat sidewall is less than that of other sections of the spring seat sidewall, and the inner diameter of the top section of the spring seat sidewall is greater than that of other sections of the spring seat sidewall. A circular horizontal stepped surface is formed at the junction of the top section of the spring seat sidewall and other sections of the spring seat sidewall. An internal thread is formed in the top section of the spring seat sidewall. A circular sealing element is also provided, with an external thread formed on its outer circumference. The circular sealing element is screwed onto the top of the spring seat using this external thread. A central hollow hole is formed in the center of the circular sealing element. An upper pull rod connector is also provided, with a cylindrical connector at the top that passes upward through the central hollow hole of the circular sealing element. A blind hole with an internal thread is opened in the center of the cylindrical connector, and the lower end of the upper pull rod is screwed into this blind hole. A central part of the upper pull rod connector is formed... The spring has an annular rib, the upper end of which presses against the lower end face of the annular rib, and the upper end face of the annular rib presses against the lower end face of the annular sealing element. The annular sealing element has 6-12 positioning holes, evenly distributed along its circumference. The sidewall of the spring seat has multiple vertical positioning screw holes, the openings of which are located on the horizontal stepped surface of the spring seat. These screw holes are evenly distributed along the circumference of the sidewall, and the number of screw holes is the same as the number of positioning holes. The distance between the positioning screw holes and the central axis of the sidewall of the spring seat is equivalent to the distance between the positioning holes and the central axis of the annular sealing element. A positioning bolt is also provided, consisting of a screw and a nut. The screw of the positioning bolt passes through the positioning hole of the annular sealing element and is screwed into the positioning screw hole of the sidewall of the spring seat.The locating bolts have internal hexagonal sockets in the nuts, and each locating bolt is equipped with a cotter pin. The locating bolts also have pin holes for the cotter pins to pass through, with the pin hole's axis perpendicular to the locating bolt's axis. A bolt interlocking mechanism made of metal is also included, consisting of a first interlocking plate, a second interlocking plate, a third interlocking plate, a fourth interlocking plate, a fifth interlocking plate, a sixth interlocking plate, and a seventh interlocking plate connected vertically in sequence. The fourth interlocking plate has two screw holes for the locating bolt shanks to pass through, the distance between the two screw holes being equal to the distance between any two adjacent locating holes on the annular sealing component. The diameter of each screw hole is larger than the diameter of the locating bolt shank but smaller than the diameter of the locating bolt nut. The second and sixth interlocking plates are located in the same plane and are parallel to the fourth interlocking plate. The first, third, fifth, and seventh interlocking plates are perpendicular to the fourth interlocking plate, the first interlocking plate is parallel to the third interlocking plate, and the fifth interlocking plate is parallel to... The seventh interlocking plate; the second and sixth interlocking plates each have nut holes for the nuts of the positioning bolts to pass through; the first, third, fifth, and seventh interlocking plates each have locking holes for cotter pins to pass through; the positioning bolts are paired; in each pair of positioning bolts, the shank of the first positioning bolt passes through the first shank hole of the fourth interlocking plate, the shank of the second positioning bolt passes through the second shank hole of the fourth interlocking plate, the nut of the first positioning bolt passes through the nut hole of the second interlocking plate, and the nut of the second positioning bolt passes through the nut hole of the sixth interlocking plate. The nuts of the two positioning bolts press the fourth interlocking plate onto the upper end face of the annular sealing member; the cotter pin corresponding to the first positioning bolt passes through the locking hole of the first interlocking plate, the pin hole of the first positioning bolt, and the locking hole of the third interlocking plate; the cotter pin corresponding to the second positioning bolt passes through the locking hole of the fifth interlocking plate, the pin hole of the second positioning bolt, and the locking hole of the seventh interlocking plate.

2. The insulating pull rod for easy adjustment of spring preload according to claim 1, characterized in that... The plane containing the first and seventh chain pieces forms an angle greater than 60 degrees.

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