CN212799169U - Speed regulating device of automatic reset progressive overspeed-proof safety device - Google Patents

Abstract

The utility model provides an automatic speed adjusting device of gradual overspeed safety ware that prevents that resets, relates to the technical field of overspeed protection of various sharp and rotary motion's mechanical parts, and the safety ware includes main shaft, brake gear, big end cover, tail end lid, and the main shaft passes through the bearing and supports on big end cover and tail end lid, and brake gear is connected with the main shaft, is equipped with speed adjusting device on the safety ware, and speed adjusting device includes: the centrifugal block centrifugal device comprises a centrifugal seat sleeved on the outer surface of a main shaft, a centrifugal shaft arranged in a side hole of the centrifugal seat, a disc-shaped spring and a centrifugal block sleeved at the tail end of the centrifugal shaft, a friction plate adhered to the outer surface of the centrifugal block, a brake drum arranged between a large end cover and a tail end cover, and a speed regulating spring hooped on the outer ring of the centrifugal block.

Description

Speed regulating device of automatic reset progressive overspeed-proof safety device

Technical Field

The utility model relates to a technical field of various sharp and rotary motion's mechanical parts's overspeed protection, concretely relates to automatic speed adjusting device of overspeed safety ware is prevented to gradual of resetting.

Background

The overspeed protection safety device is the most important safety device in mechanical equipment, and when the running speed of the mechanical equipment reaches the preset protection speed of the overspeed protection safety device, the overspeed protection safety device can act to brake the equipment to prevent accidents. The conventional overspeed protector is a gear cone drum-shaped progressive safety device, and the braking force is increased along with the increase of the braking distance in the braking process. The progressive safety device is complex in structure, and can be used only by manual reset after action, so that the operation is complex. The device is inconvenient to use in the occasions with narrow operation space or when the installation space of mechanical equipment is insufficient. In order to meet the market demand, a gradual loading type anti-falling safety device which has a simple structure and reliable performance and can automatically reset the braking force is produced. The working principle of the existing automatic resetting progressive loading type anti-falling safety device is as follows: when the rotating speed of the main shaft exceeds the set action speed, the centrifugal shaft provided with the centrifugal block is thrown out from the groove of the main shaft of the safety device by overcoming the spring force, and a friction plate arranged at the upper end of the thrown centrifugal block is in contact with the inner side surface of the static brake drum to generate rotary friction, so that a brake torque is generated. Meanwhile, the flange at the lower end of the centrifugal shaft is thrown out of the main shaft groove and then rotates together with the centrifugal seat and rotates relative to the main shaft. The section of the outer surface of the contact part of the main shaft of the safety device and the centrifugal block is of a variable-radius polygonal structure, a flange at the lower end of the centrifugal shaft is thrown out of a main shaft groove and then is subjected to relative corner dislocation with the main shaft, and the distance between the contact part of the main shaft and the centrifugal block and the center of the main shaft is increased along with the increase of the corner dislocation of the main shaft and the centrifugal block. The compression amount of the disc spring arranged on the centrifugal shaft is increased along with the movement of the centrifugal shaft, so that the pressing force provided by the disc spring to the centrifugal block is gradually increased, the braking force of the safety device is gradually increased finally, the protection target stops moving after the safety device finishes braking, when the safety device gear drives the main shaft to rotate reversely, the centrifugal shaft moves from a larger radius part of the outer surface of the main shaft to a smaller radius part and finally returns to a groove of the main shaft, and the braking torque of the safety device is completely relieved.

However, in the above technology, since the safety devices are applied to different lifting devices at different operating speeds, and the safety devices need to be adjusted to matching operating speeds (protection speeds), however, the form and mounting structure of the speed regulating spring of the anti-falling safety device of this type are inconvenient for personnel to operate, thereby causing inconvenience in speed regulation of the safety device, and therefore, a speed regulating device is provided for the progressive anti-falling safety device capable of automatically resetting.

SUMMERY OF THE UTILITY MODEL

To prior art not enough, the utility model discloses the purpose is in the speed adjusting device who provides an automatic reset's gradual overspeed safety ware of preventing, and the control speed governing spring of being convenient for is exerted the size of the tensile force on the centrifugal piece, realizes the control of safety ware rotational speed when throwing away the centrifugal piece, and then finally realizes adjusting the action speed of safety ware, and concrete scheme is as follows:

the utility model provides an automatic speed adjusting device of gradual overspeed breaker of preventing that resets, the breaker includes main shaft, brake gear, big end cover, tail end lid, the main shaft passes through the bearing and supports on big end cover and tail end lid, brake gear pass through the key-type connect in the end that stretches out of main shaft, be equipped with speed adjusting device on the breaker, speed adjusting device includes: the centrifugal device comprises a centrifugal seat sleeved on the outer surface of a main shaft, a centrifugal shaft arranged in a side hole of the centrifugal seat, a disc spring and a centrifugal block sleeved at the tail end of the centrifugal shaft, a friction plate adhered to the outer surface of the centrifugal block, a brake drum arranged between a large end cover and a tail end cover, and a speed regulating spring hooped on the outer ring of the centrifugal block.

Furthermore, the two ends of the speed regulating spring are arranged at intervals to form a gap, the adjusting structure is arranged in the gap, and the adjusting structure is connected with the two ends of the speed regulating spring to adjust the distance between the two ends of the speed regulating spring.

Further, it includes two-way nut, derotation screw thread screw rod, positive screw thread screw rod and installation component to adjust the structure, two-way nut passes through the installation component fixed set up in on the surface of centrifugal seat, derotation screw thread screw rod, positive screw thread screw rod pass through installation component reciprocal slidable mounting relatively in on the centrifugal seat, just derotation screw thread screw rod, the one end that positive screw thread screw rod kept away from each other respectively with speed governing spring's both ends are connected, two-way nut's both ends are equipped with positive screw thread and derotation screw thread respectively, positive screw thread, derotation screw thread respectively with positive screw thread screw rod, derotation screw thread screw rod threaded connection.

Furthermore, one end of each of the reverse-rotation threaded screw and the forward-rotation threaded screw is provided with a connecting piece, and the connecting pieces are provided with hanging holes.

Further, the installation component comprises a first support, a second support and a third support which are identical in structure, the first support, the second support and the third support are arranged on the outer surface of the centrifugal seat at intervals, the bidirectional nut is clamped with the first support, and the forward-rotation threaded screw and the backward-rotation threaded screw are arranged in the second support and the third support in a penetrating mode in a sliding mode.

Furthermore, a limiting clamping groove matched with the first support is formed in the bidirectional nut in a surrounding mode.

Furthermore, locking nuts are arranged at one ends, close to the two-way nut, of the reverse-rotation threaded screw rod and the forward-rotation threaded screw rod in a penetrating mode.

Compared with the prior art, the beneficial effects of the utility model are as follows:

(1) the distance between the two ends of the speed regulating spring is adjusted along the circumferential direction of the speed regulating spring, so that the expansion degree of the speed regulating spring is adjusted, the tension force applied to the centrifugal block by the speed regulating spring is controlled, the rotating speed of the safety device is controlled when the centrifugal block is thrown out, and the action speed of the safety device is finally adjusted, so that an operator can conveniently adjust the safety devices of different devices to corresponding action speeds;

(2) in addition, the reverse-rotation threaded screw and the forward-rotation threaded screw drive the speed regulating spring to be twisted when rotating and the rotation directions of the reverse-rotation threaded screw and the forward-rotation threaded screw are opposite relative to the rotation directions of the two-way nut, so that the speed regulating spring cannot be finally deformed, and the speed regulating spring is ensured to normally compress the centrifugal block.

Drawings

FIG. 1 is a cross-sectional view taken along line A-A of the present invention;

FIG. 2 is a cross-sectional view taken along line B-B of the safer of the present invention;

FIG. 3 is a half sectional view of the present invention;

FIG. 4 is a cross-sectional view of the centrifuge bowl of the present invention;

FIG. 5 is an overall schematic view of an adjustment mechanism;

FIG. 6 is a schematic structural view showing the position of a limiting slot on a two-way nut;

FIG. 7 is a cross-sectional view taken along line C-C of the present invention.

Reference numerals: 1. a retainer ring for a shaft; 2. a first retainer ring; 3. a brake gear; 4. a main shaft; 5. a first seal ring; 6. a first bearing; 7. a large end cap; 8. oil sealing; 9. a first set screw; 10. a brake drum; 11. a tail end cover; 12. a first limit switch trigger pin; 13. a second bearing; 14. a second limit switch trigger pin; 15. a limit switch trigger spring; 16. a second retainer ring; 17. a retainer ring for a bore; 18. a centrifugal seat; 19. a centrifugal shaft; 20. a disc-shaped spring; 21. a third retainer ring; 22. a centrifugal block; 23. a second seal ring; 24. a speed regulating spring; 25. a friction plate; 26. a third seal ring; 27. a baffle plate; 28. a fourth seal ring; 29. a housing; 30. a limit switch; 31. a two-way nut; 311. a limiting clamping groove; 32. a reverse-rotation threaded screw; 33. a positive-rotation threaded screw; 34. mounting the component; 341. a first support; 342. a second support; 343. a third support; 35. a connecting member; 351. hanging holes; 36. and locking the nut.

Detailed Description

The present invention will be described in further detail with reference to the following examples and drawings, but the embodiments of the present invention are not limited thereto.

As shown in fig. 1, a speed regulating device of an automatic reset progressive overspeed safety device is provided on a safety device to regulate the operating speed of the safety device.

As shown in fig. 1, the safety device includes a main shaft 4, a brake gear 3, a large end cover 7, and a tail end cover 11, the main shaft 4 is supported on the large end cover 7 and the tail end cover 11 through a first bearing 6 and a second bearing 13, a first seal ring 5 and an oil seal 8 are respectively installed at two ends of the first bearing 6, the brake gear 3 is connected to an extending end of the main shaft 4 through a key, and one end of the brake gear 3 is axially positioned through a first retainer ring 2 and a shaft retainer ring 1. Be equipped with speed adjusting device on the safer, speed adjusting device includes: the centrifugal device comprises a centrifugal seat 18, a centrifugal shaft 19, four centrifugal blocks 22, a friction plate 25, a brake drum 10 and a speed regulating spring 24, wherein the centrifugal seat 18 is sleeved on the outer ring of a main shaft 4, one end of the centrifugal shaft 19 is installed in a hole of the centrifugal seat 18, a protrusion at one end of the centrifugal shaft 19 is embedded in a groove on the surface of the main shaft 4, a third retaining ring 21, the centrifugal blocks 20 and the centrifugal blocks 22 are sleeved at the other end of the centrifugal shaft 19, as shown in the figure, the number of the centrifugal blocks 22 is four, the number of the centrifugal blocks 22 is uniformly arranged around the central axis of the centrifugal seat 18, a second sealing ring 23 is arranged between the centrifugal blocks 22 and the centrifugal shaft 19. The speed regulating spring 24 is a whole circle and is mounted and hooped on the outer surface of the centrifugal block 22. One end of the brake drum 10 is connected with the big end cover 7 through a first fixing screw 9, and the other end of the brake drum is connected with the tail end cover 11 through a screw.

As shown in fig. 4, fig. 4 is a cross-sectional view of the centrifugal seat 18 in the axial direction of the present invention, the cross-sectional shape of the centrifugal seat 18 is approximately circular, and four grooves with gradually decreasing inner diameters and distributed in a stepped manner are correspondingly formed on the centrifugal seat 18, the grooves are positions where structures such as the centrifugal shaft 19 are located when the centrifugal shaft is in a non-working state, and the grooves are used for providing a movement space for the structures such as the centrifugal shaft 19, the butterfly spring 20, the centrifugal block 22, and the like.

With reference to fig. 3 and 5, in order to adjust the operating speed of the safety device, the adjusting device further includes an adjusting structure, which is disposed on the centrifugal seat 18 and is used for changing the pressing force of the governor spring 24 on the centrifugal block 22 along the circumferential direction of the governor spring 24.

Specifically, two ends of the speed regulating spring 24 are arranged at intervals to form a gap, the adjusting structure is arranged in the gap, and the adjusting structure is connected with two ends of the speed regulating spring 24 to adjust the distance between the two ends of the speed regulating spring 24, that is, the circumferential expansion and contraction degree of the speed regulating spring 24 is adjusted, so that the elastic capacity of the speed regulating spring 24 is adjusted, and further the pressing force of the speed regulating spring 24 on the centrifugal block 22 is adjusted.

With reference to fig. 5 and 6, in the present embodiment, the adjusting structure includes a bidirectional nut 31, a reverse-rotation threaded rod 32, a forward-rotation threaded rod 33, and a mounting assembly 34, the bidirectional nut 31 is fixedly disposed on the outer surface of the centrifugal base 18 through the mounting assembly 34, and the reverse-rotation threaded rod 32 and the forward-rotation threaded rod 33 are slidably mounted on the centrifugal base 18 through the mounting assembly 34 in a reciprocating manner. Specifically, the mounting assembly 34 includes a first support 341, a second support 342, and a third support 343 that are identical in structure, the first support 341, the second support 342, and the third support 343 are disposed on an outer surface of the centrifugal seat 18 at intervals by screws, and all of the three are in an "Ω" shape, and the first support 341 is located between the second support 342 and the third support 343. The two-way nut 31 is surrounded by a limit slot 311 adapted to the first support 341, so that the two-way nut 31 is connected to the first support 341 in a clamping manner, and the two-way nut 31 is prevented from moving. The forward-rotation threaded screw 33 and the reverse-rotation threaded screw 32 are slidably arranged in the second support 342 and the third support 343.

The two ends of the bidirectional nut 31 are respectively provided with a forward thread and a backward thread, the forward thread and the backward thread are respectively in threaded connection with the forward thread screw 33 and the backward thread screw 32, and when the forward thread screw 33 and the backward thread screw 32 are screwed, the forward thread screw 33 and the backward thread screw 32 can rotate relative to the bidirectional nut 31, so that the approach or the separation of the two can be controlled.

The end that the backspin thread screw rod 32, the positive thread screw rod 33 kept away from each other is connected with the both ends of speed governing spring 24 respectively, and is concrete, and the homogeneous body coupling of the one end of backspin thread screw rod 32, positive thread screw rod 33 has connecting piece 35, and connecting piece 35 is platelike structure, has seted up on the connecting piece 35 and has linked up hole 351, and linked up hole 351 can articulate with the 24 tip of speed governing spring.

When the forward-rotation threaded screw 33 and the backward-rotation threaded screw 32 are rotated, the forward-rotation threaded screw and the backward-rotation threaded screw are close to or far from each other, and the speed regulating spring 24 is driven to stretch or compress, so that the distance between two ends of the speed regulating spring 24 is increased or decreased, the elastic capacity of the speed regulating spring 24 is adjusted, and the pressing force of the speed regulating spring 24 on the centrifugal block 22 is adjusted.

As shown in fig. 6, preferably, locking nuts 36 are respectively disposed at the ends of the reverse-rotation threaded rod 32 and the forward-rotation threaded rod 33 close to the two-way nut 31, and after the reverse-rotation threaded rod 32 and the forward-rotation threaded rod 33 are rotated to a certain position, the locking nuts 36 are pressed against the two-way nut 31 by rotating the locking nuts 36, so as to improve the connection strength between the reverse-rotation threaded rod 32, the forward-rotation threaded rod 33 and the two-way nut 31.

Referring to fig. 1 and 7, the safety device is further provided with a trigger mechanism, the trigger mechanism includes a housing 29, a limit switch 30, a first limit switch trigger pin 12, a second limit switch trigger pin 14, a limit switch trigger spring 15, a baffle 27, a third seal ring 26 and a fourth seal ring 28, the first limit switch trigger pin 12 is installed in a radial hole at the tail end of the main shaft 4, the second limit switch trigger pin 14 is installed in an axial hole at the tail end of the main shaft 4, and the axial hole is communicated with the radial hole. One end of the second limit switch trigger pin 14 is in contact with the first limit switch trigger pin 12, the other end of the second limit switch trigger pin is sleeved in an inner hole of a limit switch trigger spring 15, and the other end of the limit switch trigger spring 15 is supported on a second retainer ring 16 and a hole retainer ring 17. The third and fourth seal rings 26, 28 are mounted on opposite sides of the shroud 27, and the shroud 29 is mounted to the end of the end cap 11. The baffle plate 27, the third seal ring 26 and the fourth seal ring 28 are interposed between the cover 29 and the tail end cover 11, and the limit switch 30 is mounted on the baffle plate 27.

In the invention, the first limit switch trigger pin 12 arranged in the radial hole of the main shaft 4 is positioned in the groove on the upper surface of the centrifugal seat 18 under the non-braking condition, and when the centrifugal seat 18 and the main shaft 4 are braked by the safety device to rotate relatively, the first limit switch trigger pin 12 is contacted with flanges at two sides of the groove of the centrifugal seat 18 and is pressed into the shaft by the flanges.

The safety device has the following structural principle: the rack of the construction lifter is meshed with a safety device brake gear 3, and the brake gear 3 is connected to the extending end of a main shaft 4 through a key. The safety device runs normally downwards along the guide rail frame along with the construction elevator, the rack fixedly arranged on the guide rail frame of the construction elevator drives the brake gear 3 to rotate, the brake gear 3 drives the main shaft 4 to rotate through a key, and the centrifugal seat 18 arranged on the main shaft 4 and the centrifugal shaft 19 which penetrates through the centrifugal seat 18 and is seated in the groove of the main shaft 4 synchronously rotate along with the main shaft 4. When the elevator runs at normal speed, the centrifugal shaft 19 is under the tightening limit of the speed regulating spring 24, the centrifugal shaft 19 and the centrifugal seat 18 keep synchronous rotation, and the safety device does not generate braking torque.

The braking principle of the safety device is as follows: when the construction hoist runs over speed, the centrifugal shaft 19 generates a greater centrifugal force which gradually overcomes the tightening force limit of the governor spring 24. When the descending overspeed value of the elevator exceeds a certain threshold, the centrifugal shaft 19 completely overcomes the clamping force of the speed regulating spring 24 and is thrown out from the groove of the main shaft 4, at the moment, the centrifugal shaft 19, the centrifugal seat 18 and the main shaft 4 rotate relatively, and the rotation angle of the centrifugal seat 18 and the centrifugal shaft 19 is smaller than that of the main shaft 4. The centrifugal shaft 19 rotates to a position farther away from the groove of the main shaft 4 along with the centrifugal seat 18, and the centrifugal shaft 19 gradually slides to a position where the diameter of the main shaft 4 is larger. The centrifugal block 22 sleeved on the upper end of the centrifugal shaft 19 is pressed by the main shaft 4 to contact with the brake drum 10. The brake drum 10 is a fixed part, so that the friction plate 25 adhered to the upper surface of the centrifugal block 22 and the brake drum 10 generate a braking torque through rotating friction. With the increase of the braking distance and the continuous increase of the relative rotation angle between the main shaft 4 and the centrifugal shaft 19, the centrifugal shaft 19 moves to a position with a larger diameter of the main shaft 4, at this time, the centrifugal block 22 is already attached to the inner cavity of the brake drum 10 and cannot extend outward any more, however, the centrifugal shaft 19 continues to move to a position with a larger diameter of the main shaft 4, the centrifugal shaft 19 and the centrifugal block 22 sleeved thereon generate relative displacement, the centrifugal shaft 19 starts to compress the disc spring 20, a larger positive pressure is provided for the centrifugal block 22, and finally, the increase of the braking torque is realized. Until the braking force stops the elevator, the main shaft 4 stops rotating, and the centrifugal seat 18 and the centrifugal shaft 19 also stop rotating relative to the main shaft 4.

In the braking process, as the centrifugal seat 18 and the main shaft 4 rotate relatively, the extending end of the first limit switch trigger pin 12 arranged in the radial hole at the tail end of the main shaft 4 is contacted with the protrusions at two sides of the groove of the centrifugal seat 18 and is pressed into the shaft to be contacted with the second limit switch trigger pin 14, the contact ends of the first limit switch trigger pin 12 and the second limit switch trigger pin 14 are conical, and the displacement of the downward movement of the first limit switch trigger pin is transferred to the second limit switch trigger pin through the conical end to be converted into horizontal displacement of the rightward movement of the second limit switch trigger pin. The second limit switch trigger pin 14 is displaced rightward to overcome the pressure of the limit switch trigger spring 15 and extend out of the end face of the main shaft 4 to contact the trigger terminal of the limit switch 30. Limit switch 30 is triggered and shuts off power to the elevator downlink control circuit.

When the fault of the lifter is relieved, the lifter runs upwards to drive the braking gear 3 of the safety device to rotate reversely, the braking gear 3 drives the main shaft 4 to rotate reversely, the friction force of the outer surface of the main shaft 4, which is in contact with the centrifugal shaft 19, is smaller than the friction force between the centrifugal block 22 and the braking drum 10, the main shaft 4, the centrifugal shaft 19 and the centrifugal seat 18 generate reverse relative rotation, and the centrifugal shaft 19 moves from the larger diameter part of the main shaft 4 to the smaller diameter part until the centrifugal shaft 19 returns to the groove on the outer surface of the main shaft 4. At this time, the braking force is completely released, and the safety device is restored to the initial state.

When the lifter runs upwards and the centrifugal shaft 19 of the safety device returns to the groove of the main shaft 4, the first limit switch trigger pin 12 protrudes from two sides of the groove on the upper surface of the centrifugal seat 18 and returns to the middle groove, under the action of the spring pressure of the limit switch trigger spring 15, the second limit switch trigger pin 14 ejects out the first limit switch trigger pin 12 and restores the first limit switch trigger pin to the original position, the trigger state of the limit switch 30 is released, and the power supply of the descending control circuit of the lifter restores.

It is above only the utility model discloses a preferred embodiment, the utility model discloses a scope of protection does not only confine above-mentioned embodiment, the all belongs to the utility model discloses a technical scheme under the thinking all belongs to the utility model discloses a scope of protection. It should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (7)

1. The utility model provides an automatic speed adjusting device of gradual overspeed breaker of preventing that resets, the breaker includes main shaft (4), brake gear (3), big end cover (7), tail end lid (11), main shaft (4) pass through the bearing support on big end cover (7) and tail end lid (11), brake gear (3) pass through the key connection in the end that stretches out of main shaft (4), be equipped with speed adjusting device on the breaker, speed adjusting device includes: the centrifugal device is characterized by further comprising an adjusting structure, wherein the adjusting structure is arranged on the centrifugal seat (18), and is used for changing the pressing force of the speed regulating spring (24) on the centrifugal block (22) along the circumferential direction of the speed regulating spring (24).

2. The speed regulating device of an automatic reset progressive overspeed governor according to claim 1, wherein both ends of the speed regulating spring (24) are spaced apart to form a gap, the adjusting structure is disposed in the gap, and the adjusting structure is connected with both ends of the speed regulating spring (24) to adjust a distance between both ends of the speed regulating spring (24).

3. The speed regulating device of the automatic resetting progressive overspeed-preventing safety device according to claim 2, wherein the regulating structure comprises a bidirectional nut (31), a reverse-rotation threaded screw (32), a forward-rotation threaded screw (33) and a mounting component (34), the bidirectional nut (31) is fixedly arranged on the outer surface of the centrifugal seat (18) through the mounting component (34), the reverse-rotation threaded screw (32) and the forward-rotation threaded screw (33) are slidably mounted on the centrifugal seat (18) relatively in a reciprocating manner through the mounting component (34), ends of the reverse-rotation threaded screw (32) and the forward-rotation threaded screw (33) which are far away from each other are respectively connected with two ends of the speed regulating spring (24), two ends of the bidirectional nut (31) are respectively provided with a forward-rotation thread and a reverse-rotation thread, and the forward-rotation thread and the reverse-rotation thread are respectively connected with the forward-rotation threaded screw (33), The reverse-rotation threaded screw (32) is in threaded connection.

4. The speed regulating device of the automatic resetting progressive overspeed-preventing safety device as claimed in claim 3, wherein one end of each of the reverse-rotation threaded screw (32) and the forward-rotation threaded screw (33) is provided with a connecting piece (35), and the connecting piece (35) is provided with a hanging hole (351).

5. The speed regulating device of the automatic resetting progressive overspeed preventer according to claim 3, characterized in that the mounting assembly (34) comprises a first support (341), a second support (342) and a third support (343) which are consistent in structure, the first support (341), the second support (342) and the third support (343) are arranged on the outer surface of the centrifugal seat (18) at intervals, the bidirectional nut (31) is clamped with the first support (341), and the forward-rotation threaded screw (33) and the backward-rotation threaded screw (32) are slidably arranged in the second support (342) and the third support (343).

6. The speed regulating device of the automatic resetting progressive overspeed-preventing safety device according to claim 5, characterized in that a limiting clamping groove (311) matched with the first support (341) is formed on the bidirectional nut (31) in a surrounding manner.

7. The speed regulating device of the automatic reset progressive overspeed preventer according to claim 3, characterized in that locking nuts (36) are respectively arranged at one ends of the reverse-rotation threaded screw (32) and the forward-rotation threaded screw (33) close to the bidirectional nut (31) in a penetrating manner.

Images