Buffer type speed difference anti-fall device based on leaf spring

Abstract

This patent provides a buffering speed difference anti-falling device which can not only reliably lock, but also prevent a large force from being generated on the human body when locked, and has a buffering effect. It includes a frame, a central axis, a drum wheel rotatably arranged on the central axis, and a safety rope wound on the drum wheel; a locking structure including a pawl and a ratchet wheel is arranged in the space between the frame and the drum wheel disc, a ratchet wheel guide device is fixed on the frame, and the ratchet wheel can be rotatably arranged on the ratchet wheel guide device relative to the ratchet wheel guide device, one end of the leaf spring is fixed on the central axis, and the other end extends into the slide groove opened on the inner circumference of the ratchet wheel and slides with the slide groove; the pawl is sleeved on the ratchet pawl shaft fixed on the drum wheel; when the rotation speed of the drum wheel rotating in the working direction exceeds the locking speed, the pawl rotates around the pawl shaft under the action of centrifugal force, the pawl is stuck in the ratchet wheel groove, the drum wheel and the pawl drive the ratchet wheel to start rotating together, and under the action of the leaf spring, the rotation stops after a certain angle.

Description

Technical Field

[0001] This patent relates to the field of safety protection equipment, and in particular to a buffer-type speed difference anti-fall device based on a leaf spring for workers to use when working at height. Background Art

[0002] High-altitude operations and various infrastructure construction are in full swing, and people have higher and higher requirements for work safety. The definition of safety belts and safety ropes is no longer limited to the traditional concept. According to different use occasions, it has been expanded to speed differential fall arresters, rail fall arresters and rope fall arresters. Among them, the speed differential fall arrester, also known as the speed differential automatic controller, can meet the changing working environment and production needs, so it is the most widely used, with a market share of about 80% of all fall arresters. It is currently an ideal anti-high-altitude fall device, which fundamentally solves the problem of frequent high-altitude safety accidents.

[0003] When working at height, one end of the frame of the speed differential fall arrester is suspended at a high place, and the safety rope extends out of the outer end of the speed differential fall arrester and is hung on the operator's waist (or a full belt tied to the operator's waist). The safety rope moves with the worker's work. Its working principle is that when the operator descends at a normal speed during normal work, the safety rope wound on the drum of the fall arrester follows the movement of the human body and is released to maintain a suitable length. Once the operator descends too fast or falls, the safety rope release speed exceeds the normal speed, and the internal mechanism of the fall arrester takes effect, the drum is locked, and the safety rope cannot be released, avoiding the impact injury that may be caused by the operator's continued fall. When the operator resumes normal work, the fall arrester can be manually unlocked for the next safety protection.

[0004] For workers working at heights, speed differential fall arresters are essential protective gear. However, general high-altitude speed differential fall arresters do not have a buffering function, that is, they stop rotating the moment the drum is locked (of course, the safety rope is no longer released), which means that the speed of the drum drops to zero instantly, and the operator's descent speed also drops to zero instantly, which causes the outer end of the safety rope tied to the operator's waist (or the full belt around the operator's waist) to exert a large force on the human body, causing serious harm to the human body. Therefore, the research on speed differential fall arresters with a buffering function is very necessary and has broad application prospects. Summary of the invention

[0005] This patent aims to solve the problem that the speed differential fall arrester stops immediately at the moment of locking, which has a great impact on the human body. It provides a buffer-type speed differential fall arrest device based on a leaf spring, which can not only reliably lock but also prevent a large force on the human body when locking. It has a buffering effect and is used for safety protection of workers when working at heights.

[0006] The purpose of this patent is achieved through the following technical solutions:

[0007] The buffer-type speed difference anti-fall device based on leaf spring described in this patent comprises: a frame 23, a central shaft 5 fixed on the frame 23, a drum wheel 6 rotatably arranged on the central shaft located in the frame, the inner end of the safety rope 21 wound on the drum wheel 6 is fixed on the drum wheel, and the outer end passes through the frame 23 and extends outward; the safety rope 21 is released when the drum wheel 6 rotates in the working direction, and the safety rope 21 is retracted when it rotates in the non-working direction opposite to the working direction; the locking structure including the pawl 7 and the ratchet 19 is arranged in the space between the frame 23 and the disc of the drum wheel 6; the tooth grooves on the ratchet wheel are evenly distributed on the outer periphery of the ratchet wheel 19, and the pawl 7 is located outside the outer periphery of the ratchet wheel; A ratchet guide device is fixed on the frame opposite to the drum disc, and the ratchet guide device includes an upper baffle and a lower baffle contacting the two end surfaces of the ratchet 19, and an arc plate fixed between the upper baffle and the lower baffle, and the arc surface of the arc plate is slidably matched with the inner circumference of the ratchet; the rotation axis of the ratchet 19 is coaxial with the rotation axis of the drum 6; an internal buffer damping device is provided between the central shaft 5 and the inner circumference of the ratchet 19, which can apply resistance to the rotating ratchet 19 so that the ratchet gradually stops rotating along the working direction, and the internal buffer damping device includes a leaf spring 4, one end of the leaf spring 4 is fixed on the central shaft 5, and the other end extends into the slide groove opened on the inner circumference of the ratchet 19 and slidably matches with the slide groove;

[0008] The ratchet 7 is mounted on a ratchet shaft 15 fixed on the drum 6. A stopper 10 is provided on the drum 6 to limit the ratchet 7 from swinging around the ratchet shaft 15 in a certain direction, i.e., the direction of stopping rotation. An elastic element is provided between the drum 6 and the ratchet 7 to keep the ratchet 7 in contact with the stopper 10 in a normal state.

[0009] When the rotation speed of the drum 6 around the central axis 5 in the working direction exceeds the set locking speed, the pawl 7 rotates around the pawl shaft 15 in the locking direction opposite to the stopping direction under the action of centrifugal force, and the tip of the pawl 7 is stuck in the tooth groove of the ratchet 19, and the drum 6 and the pawl 7 drive the ratchet 19 to start rotating in the working direction. At this time, under the action of the internal buffer damping device, the drum 6, the pawl 7 and the ratchet 19 stop rotating after rotating a certain angle a.

[0010] The beneficial effects of this patent are as follows: when the worker works at high altitude, one end of the frame is relatively fixed and suspended at a high place, and the outer end of the safety rope 21 is hung on the waist of the worker, and the safety rope 21 moves with the worker's work. During normal operation, the rotation speed of the drum wheel 6 is very slow, that is, the centrifugal force on the ratchet 7 of the drum wheel 6 disc is very small, which cannot overcome the force of the elastic element on the ratchet 7. The ratchet 7 is basically in contact with the stop column 10 and basically does not rotate around the ratchet shaft 15, so that the tip of the ratchet 7 does not contact the ratchet 19, and the drum wheel 6 connected with the ratchet 7 can smoothly rotate in the working direction, and the safety rope is gradually released. Once a fall occurs during operation, the outer end of the safety rope is subjected to the force of the human body falling, driving the drum wheel 6 to rotate rapidly. When the drum wheel speed reaches the locking speed, the ratchet 7 on the drum wheel 6 disc is subjected to a large centrifugal force, and the ratchet 7 overcomes the force of the elastic element and rotates around the ratchet shaft 15 in the locking direction. The tip of the ratchet 7 will be stuck in the tooth groove on the ratchet 19 to achieve a one-time locking. Since the ratchet is not fixed on the frame but can rotate relative to the frame, the drum and the pawl can still drive the ratchet to continue rotating in the working direction during the first locking, that is, the ratchet 19 rotates accordingly, and the internal buffer damping device starts to work. The ratchet 19 must overcome the bending moment of the leaf spring 4 to rotate, and the leaf spring 4 plays a role in hindering the rotation of the ratchet 19, hindering the rotation of the ratchet and slowing down the rotation speed. In this way, the drum 6, the pawl 7, and the ratchet 19 gradually stop rotating after rotating at a certain angle a, realizing the second locking, avoiding the impact force on the human body caused by the first locking of the drum, achieving the buffering effect and realizing the second locking to stop the fall, ensuring the safety of the user.

[0011] This locking mechanism composed of pawl, ratchet, etc. is an external meshing ratchet mechanism. Since the leaf spring will deform when the ratchet rotates, such as bending in the circumferential direction of the central axis, the two ends of the leaf spring cannot be fixed at the same time. When one end is fixed, the other end should be a free end that can be freely extended and retracted.

[0012] The ratchet guide device includes an upper baffle plate and a lower baffle plate that contact the two end surfaces of the ratchet 19, and an arc plate fixed between the upper baffle plate and the lower baffle plate, and the arc surface of the arc plate is circumferentially slidably matched with the ratchet. This ratchet guide device has a simple structure, and the ratchet is positioned axially and radially, and the ratchet can only rotate along the central axis.

[0013] As a further improvement to the above-mentioned buffered speed differential anti-fall device based on leaf spring, a safety block protruding from the inner periphery of the ratchet 19 is provided; one end of the leaf spring 4 extends into the slide groove opened on the safety block and slides in cooperation with the slide groove; when the tip of the pawl 7 is inserted into the tooth groove of the ratchet 19, the drum 6 and the pawl 7 drive the ratchet 19 to rotate a certain angle b along the working direction, the safety block contacts the arc plate 9, so that the drum 6, the pawl 7 and the ratchet 19 stop rotating; b≥a.

[0014] This structure organically combines the internal buffer damping device with the safety device that limits the maximum rotation angle of the ratchet in the working direction. When the structure of this patent is working, under the action of the internal buffer damping device, the drum 6, the pawl 7, and the ratchet 19 generally stop rotating after a certain angle a. However, it is also possible that the blocking force generated by the internal buffer damping device on the ratchet is small, or when the internal buffer damping device fails, the drum 6, the pawl 7, and the ratchet 19 still cannot stop rotating after rotating at an angle a. In order to prevent accidents, a safety device that limits the maximum rotation angle of the ratchet in the working direction is required. It can work when the ratchet 19 still cannot stop rotating after rotating at an angle a, and stop the ratchet. Specifically for this structure, the arc block, the safety block, etc. constitute a safety device. When the drum 6 and the pawl 7 drive the ratchet 19 to rotate a certain angle b in the working direction, the safety block is in rigid contact with the arc block 9, so that the ratchet 19 stops rotating. The maximum angle of rotation of the ratchet in the working direction is limited by the safety device to b. Obviously, the maximum angle b≥a that the ratchet can rotate in the working direction. In this way, the device perfectly and organically integrates the internal buffer damping device, the ratchet guide device and the safety device, and has a simple structure.

[0015] Preferably, the internal buffer damping device further comprises an internal buffer tension spring, the two ends of which are respectively connected to the safety block and the arc plate; the internal buffer tension spring applies a tension force to the ratchet in a normal state, which makes the ratchet have a tendency to rotate in the non-working direction. In this way, the internal buffer tension spring and the leaf spring together play a blocking role in the rotation of the ratchet. At the same time, the internal buffer tension spring is connected between the safety block and the arc plate in the ratchet guide device, which simplifies the overall structure and makes the force of the internal buffer tension spring on the ratchet within the plane where the ratchet is located, thereby preventing the ratchet from being subjected to an axial force.

[0016] As a further improvement to the above-mentioned buffer-type speed difference anti-fall device based on leaf spring, a safety block protruding from the inner circumference of the ratchet 19 is arranged on the inner circumference of the ratchet; one end of the leaf spring 4 is fixed on the safety block; the internal buffer damping device also includes an internal buffer compression spring, and the two ends of the internal buffer compression spring are respectively connected to the safety block and the arc plate; the internal buffer compression spring applies an elastic force to the ratchet in a normal state so that the ratchet has a tendency to rotate in the non-working direction; when the tip of the pawl 7 is stuck in the tooth groove of the ratchet 19, the drum 6 and the pawl 7 drive the ratchet 19 to rotate a certain angle c in the working direction, the internal buffer spring is completely compressed, and at this time, the arc plate, the internal buffer compression spring and the safety block are in rigid contact, so that the drum 6, the pawl 7 and the ratchet 19 stop rotating; c≥a.

[0017] In this way, the internal buffer compression spring and the leaf spring jointly block the rotation of the ratchet. At the same time, the internal buffer compression spring is connected between the safety block and the arc plate in the ratchet guide device, which simplifies the overall structure and makes the force of the internal buffer compression spring on the ratchet within the plane where the ratchet is located, preventing axial force from being applied to the ratchet.

[0018] In addition, this structure organically combines the internal buffer damping device with the safety device that limits the maximum rotation angle of the ratchet in the working direction. Specifically for this structure, the arc plate, the internal buffer compression spring, the safety block, etc. constitute the safety device. When the drum 6 and the pawl 7 drive the ratchet 19 to rotate a certain angle c in the working direction, the internal buffer compression spring is completely compressed. At this time, the arc plate, the internal buffer compression spring, and the safety block are in rigid contact, so that the drum 6, the pawl 7, and the ratchet 19 stop rotating. The safety device limits the maximum rotation angle of the ratchet in the working direction to c. Obviously, the maximum angle that the ratchet can rotate in the working direction is c≥a. This device perfectly and organically integrates the internal buffer damping device, the ratchet guide device, and the safety device, and has a simple structure.

[0019] As a further improvement of the above-mentioned buffer-type speed difference anti-falling device based on steel leaf spring, it also includes a safety rope recovery device including a coil spring 25 and a coil spring disk 22; the upper and lower ends of the central axis 5 passing through the drum 6 and the coil spring disk 22 are fixedly connected to the frame 23, the coil spring disk 22 is fixed to the lower part of the drum 6 and is located between the lower part of the drum 6 and the frame, one end of the coil spring 25 located in the coil spring disk 22 is fixed on the central axis 5, and the other end is fixed to the periphery of the coil spring disk 22; when an external force is applied to the outer end of the safety rope, the drum 6 and the coil spring disk 22 are pulled to rotate in the working direction through the safety rope 21, and the tightening torque of the coil spring 25 gradually increases; when the external force is released, the coil spring 25 drives the coil spring disk 22 and the drum 6 to rotate in the non-working direction, the length of the safety rope extending out of the frame gradually shortens, and the safety rope 21 is wound on the drum 6.

[0020] As a further improvement of the above-mentioned buffered speed differential anti-fall device based on leaf spring, it also includes an external buffer damping device, which includes an external buffer tension spring with one end connected to the frame and / or the outer end of the safety rope, and the other end of the external buffer tension spring is used to be connected to the mounting point of the buffered speed differential anti-fall device and / or the human body's safety belt.

[0021] When the drum rotates in the working direction at a speed exceeding the locking speed, the pawl swings due to centrifugal force, and the tip of the pawl is stuck in the tooth groove on the ratchet to achieve primary locking or secondary locking, or when the drum rotates to the maximum angle and stops due to the action of the safety device, the drum speed suddenly decreases, and the external buffer spring is stretched, which reduces the force of the safety rope on the human body and further improves the buffering effect.

[0022] As a further improvement to the above-mentioned buffer-type speed difference anti-fall device based on leaf springs, the leaf springs 4 are provided in multiple pieces and are arranged axially symmetrically with respect to the central axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 1 is a schematic diagram of the overall assembly of the composite buffer type speed difference anti-falling device of Example 1;

[0024] Figure 2 is a three-dimensional diagram of the composite buffer type speed difference anti-falling device of Example 1;

[0025] Figure 3 is a stereogram of Embodiment 1 (without the upper frame, etc.);

[0026] Figure 4 is a top view of Example 1 (without the upper frame, etc.);

[0027] Figure 5 yes Figure 4 AA section view;

[0028] Figure 6 yes Figure 4 BB cross-section diagram;

[0029] Figure 7 It is a three-dimensional diagram of the disc, ratchet, pawl, central shaft, etc.;

[0030] Figure 8 It is a three-dimensional picture of the drum, pawl, ratchet, coil spring plate, etc.;

[0031] Fig. 9 It is a three-dimensional view of the drum, coil spring disc, etc.;

[0032] Fig.10 It is a three-dimensional view of the coil spring disc, central axis, etc.;

[0033] Fig.11 It is a three-dimensional diagram of the coil spring disc, coil spring, center shaft, etc.;

[0034] Fig.12 It is a three-dimensional picture of the drum, coil spring disc, coil spring, etc.;

[0035] Fig.13 is a state diagram of the drum in Example 1 when it rotates by an angle a under the action of the internal buffer damping device;

[0036] Fig.14 is a three-dimensional diagram of the lower baffle, curved plate, ratchet, etc. in Example 1;

[0037] Fig.15 is a three-dimensional diagram of the upper baffle, lower baffle, curved plate, etc. in Example 1;

[0038] Fig.16is a stereoscopic diagram of the composite buffer type speed difference anti-falling device of Example 2 (with the upper frame etc. removed);

[0039] Fig.17 is a stereoscopic view of the leaf spring, ratchet, pawl, arc plate, center shaft, etc. of Example 2;

[0040] Fig.18 is a top view of Example 2 (without the upper frame, etc.);

[0041] Fig.19 yes Fig.18 CC profile of ;

[0042] Fig. 20 yes Fig.18 DD profile diagram;

[0043] Fig.21 This is a state diagram of the drum in Example 2 when it stops rotating under the action of the safety device.

[0044] In the figure, 1 is a first outer buffer tension spring, 2 is a second outer buffer tension spring, 4 is a leaf spring, 5 is a center axis, 5 is a hole, 6 is a drum, 6 is a disc, 6 is a cylinder, 6 is an opening, 7 is a ratchet, 8 is a cushion column, 9 is an arc plate (stop block), 10 is a ratchet stop column, 11 is a spring fastening screw, 12 is an inner buffer tension spring, 13 is a rope port, 14 is a ratchet tension spring, 15 is a ratchet shaft, 16 is a retaining spring, 17 is a pin, 18 is a rope column, 19 is a ratchet, 20 is an inner buffer compression spring, 21 is a safety rope, 22 is a coil spring disk, 22 is a groove, 23 is a frame, 23 is an upper frame, 23 is a lower frame, 24 is a wear-resistant sleeve, 25 is a coil spring, 26 is an upper baffle, 27 is a lower baffle, and 28 is a safety block. DETAILED DESCRIPTION

[0045] The following is a further description of this patent in conjunction with the accompanying drawings:

[0046] Embodiment 1:

[0047] See Figure 1-3A composite buffer type speed difference anti-falling device shown in the figure comprises a frame 23, a locking mechanism and a drum wheel 6, and a buffer part; the frame 23 is composed of an upper frame 231 and a lower frame 232 fixedly connected; one end of the frame has a rope port 13 for a safety rope to pass through, and the other end is a hook end. The frame 23 is provided with a central axis, and the two ends of the central axis 5 are respectively fixed to the upper frame 231 and the lower frame 232. Two ratchet guide devices symmetrical with the central axis are fixed on the lower surface of the upper frame 231 through four pads 8. Each ratchet guide device comprises an upper baffle 26, a lower baffle 27, and an arc plate (stop block) 9 located between the upper baffle and the lower baffle. The arc surface of the arc plate 9 is slidably matched with the inner circumference of the ratchet wheel 19 with teeth and grooves uniformly distributed on the outer circumference. The two end surfaces of the ratchet wheel are respectively in contact with the upper baffle and the lower baffle. Below the lower baffle 27 is the drum wheel 6, but the drum wheel 6 does not contact the lower baffle 27.

[0048] See also Figure 4-6 The drum 6 is an integrated structure consisting of a larger diameter disc (i.e., the upper end face of the drum) 61 and a smaller diameter cylinder 62 at the bottom. The drum 6 cylinder is sleeved on the central shaft 5 through a wear-resistant sleeve 24. The drum 6 and the wear-resistant sleeve 24 can rotate relative to the central shaft.

[0049] See also Figure 8-12 The cylinder 62 of the drum 6 is hollow, and the cylindrical surface of the cylinder has an opening 63. The lower end of the cylinder is fixedly connected to the coil spring disk 22 and the rope column 18 is fixed inside the hollow cylinder; the inner end of the safety rope 21 is sleeved on the rope column 18 and is wrapped around the cylindrical part of the drum 6 through the opening; the outer end of the safety rope 21 passes through the rope port 13 on the frame and is then connected to the first external buffer tension spring 1, and the other end of the first external buffer tension spring 1 is connected to the user;.

[0050] See also Figure 5 , 11 12. When working at height, the outer end of the safety rope 21 is connected to the worker through the first external buffer tension spring 1, so the speed of the user's fall is synchronized with the speed of the safety rope 21, and the safety rope 21 pulls the drum 6 to rotate along the working direction. A coil spring 25 is arranged inside the coil spring disk 22, one end of the coil spring 25 is fixed to the hole 51 at the lower end of the rotating shaft 5 passing through the coil spring disk 22 by screws, and the other end is fixed to the groove 221 opened around the coil spring disk 22 by screws, and the entire coil spring 25 is confined inside the coil spring disk 22. After the fall occurs and the danger is eliminated, the force at the outer end of the safety rope 21 is unloaded, and the safety rope 21 will shrink and wrap back around the drum 6 under the action of the coil spring 25, and the ratchet 7 will return to the initial state of contact with the stop column 10 under the tension of the ratchet limit spring 14.

[0051] See also Figure 3 , 5, 14, 15, two leaf springs 4 are interlaced at the center of the upper end of the central shaft 5, the head ends of the leaf springs 4 pass through the central shaft 5 and can move relatively freely, and the ends are fixedly connected to the inner periphery of the ratchet. There are many ways to fix the leaf springs 4 to the inner periphery of the ratchet. For example, this embodiment adopts the following structure: two safety blocks 28 protruding from the inner ring of the ratchet 19 but integrated with the ratchet are provided with a slide groove substantially equal in thickness to the leaf spring 4, a hole is provided at the end of the leaf spring 4, and the pin 17 fixed to the safety block 28 passes through the hole at the end of the leaf spring 4, so that the end of the leaf spring 4 is fixed in the radial direction of the ratchet.

[0052] See also Figure 3-5 7, the two sides of the safety block 28 on the inner periphery of the ratchet 19 are connected to the adjacent stop block 9 by an internal buffer tension spring 12 and an internal buffer compression spring 20 respectively. The internal buffer tension spring 12 applies a tension force to the ratchet in a normal state so that the ratchet has a tendency to rotate in a non-working direction. The internal buffer compression spring 20 applies a thrust force to the ratchet in a normal state so that the ratchet has a tendency to rotate in a non-working direction. The two safety blocks, the two internal buffer tension springs 12, and the two internal buffer compression springs 20 are all symmetrical about the central axis.

[0053] During normal operation, the ratchet 19 and the leaf spring 4, internal buffer tension spring 12 and internal buffer compression spring 20 connected thereto do not move relative to the frame 23. The central axis 5 is sleeved with the drum 6 and the coil spring disk 22, which are fixedly connected. The drum 6 and the coil spring disk 22 are fixed as an integrated mechanism, and rotate as a whole around the central axis 5 during normal operation; the upper end of the drum 6 disk is fixed with two centrally symmetrical ratchet shafts 15 and two ratchet stop posts 10, the two ratchet shafts 15 are respectively sleeved with ratchet 7 located at the outer periphery of the ratchet, and the two ratchet shafts 15 are respectively provided with retaining springs 16, so as to limit the axial movement of the ratchet 7 along the ratchet shaft 15; the two ratchet 7 are respectively connected with ratchet tension springs 14, one end of the ratchet tension spring 14 is connected to the tip of the ratchet 7, and the other end of the ratchet tension spring is connected to the spring fastening screw 11 fixed to the upper end of the drum 6 disk.

[0054] The locking mechanism is composed of an arc block (stop block) 9 in a fixed ratchet guide device, a ratchet 19 and a pawl 7 that can rotate around a pawl shaft 15 and is connected to a pawl tension spring 14. This locking mechanism is a double inner locking mechanism with symmetrical distribution.

[0055] The buffer part includes two forms: an internal buffer damping device and an external buffer tension spring. The internal buffer damping device includes a pair of leaf springs 4 interlaced and interlaced on the central axis and fixed at the ends on the safety block 28, a pair of internal buffer tension springs 12 connected between the safety block 28 and the stop block 9, and a pair of internal buffer compression springs 20; the external buffer tension spring is a first external buffer tension spring 1 connected to the outer end of the safety rope 21 and / or a second external buffer tension spring 2 connected to the hook end of the frame 23.

[0056] When workers work at high altitude, the hook end of the frame 23 is relatively fixedly suspended at a high place by the second external buffer tension spring 2, and the outer end of the safety rope 21 is hung on the safety belt around the worker's waist through the first external buffer tension spring 1. The safety rope 21 moves with the worker's work. During normal operation, the rotation speed of the entire drum wheel 6 is very slow, that is, the centrifugal force on the pawl 7 at the upper end of the disc of the drum wheel 6 is very small, which cannot overcome the tensile force of the pawl tension spring 14. The pawl is in contact with the blocking column 10 and will not rotate around the pawl shaft 15, so that the tip of the pawl 7 will not contact the tooth groove on the outer periphery of the ratchet, and the pawl can pass through the ratchet 19 smoothly without being hindered. Once a fall occurs during operation, the speed of the drum 6 in the working direction becomes faster due to the force of the human body falling, so that the pawl 7 on the disc of the drum 6 is subjected to a large centrifugal force, and the pawl 7 overcomes the tensile force of the pawl tension spring 14 and rotates around the pawl shaft 15. When the drum speed reaches the locking speed, the tip of the pawl 7 will swing in the direction of the tooth groove of the ratchet and get stuck in the ratchet 19, achieving a locking operation and driving the internal buffer damping device to start to work, that is, the ratchet 19 rotates along the working direction with the drum. Since one end of the leaf spring 4 is fixedly connected to the ratchet 19 and the other end is in free sliding contact with the central axis 5, the rotation of the ratchet 19 causes the leaf spring 4 to bend, and the leaf spring 4 plays a role in hindering the rotation of the ratchet 19. At the same time, a pair of internal buffer tension springs 12 connected between the ratchet 19 and the stop block 9 apply a pulling force to the ratchet to hinder the rotation of the ratchet in the working direction, and a pair of internal buffer compression springs 20 apply a thrust to the ratchet to hinder the rotation of the ratchet in the working direction, which also plays a role in hindering the rotation. The leaf spring 4, the internal buffer tension spring 12, and the internal buffer compression spring 20 work together to slow down the rotation speed of the ratchet along the working direction until the ratchet stops rotating. Fig.13 , achieving secondary locking to stop the fall and playing a buffering effect.

[0057] refer to Fig.13, when the ratchet wheel still cannot stop rotating under the joint action of the internal buffer damping devices such as the leaf spring 4, the internal buffer tension spring 12, and the internal buffer compression spring 20, the safety block 28 will continue to pull the internal buffer tension spring 12 and push the internal buffer compression spring 20, so that the internal buffer tension spring 12 is stretched and the internal buffer compression spring 20 is completely compressed, until the safety block, the internal buffer compression spring, and the arc plate are in rigid contact, and the drum wheel 6, the pawl 7, and the ratchet wheel 19 stop rotating. Therefore, even if the internal buffer damping device fails to stop the drum wheel 6 from stopping rotating, the safety device composed of the safety block, the internal buffer compression spring, and the arc plate can stop the drum wheel 6 through the rigid contact between the safety block, the internal buffer compression spring, and the arc plate to ensure the safety of the user. The safety device can eventually stop the drum wheel 6 from rotating in extreme or unexpected situations where the internal buffer damping device fails and fails to stop the drum wheel 6 from stopping rotating, and is the last line of defense to ensure the safety of the user.

[0058] See also Figure 1 , 2 , 13. When the primary locking or secondary locking is realized, or when the drum wheel rotates to the maximum angle and stops rotating due to the action of the safety device, the drum wheel speed suddenly decreases, and the two external buffer tension springs (the first external buffer tension spring and the second external buffer tension spring) are stretched, so that the impact of the safety block, the internal buffer compression spring and the stop block 9 when they collide and stop is softer, reducing the force of the safety rope on the human body, further improving the buffering effect, and ensuring the safety of the user.

[0059] Embodiment 2:

[0060] See also Figure 16-20 The embodiment 2 shown (and reference Figure 1 , 2 , 10-12), the main differences between it and Example 1 are: 1), the internal buffer damping device in Example 2 only has a leaf spring 4, without the internal buffer tension spring and internal buffer compression spring in Example 1. 2), the head end of the leaf spring 4 in Example 1 passes through the central axis 5 and can move relatively freely, and the end is fixed to the safety block 28 by a pin 17. The head ends of the multiple centrally symmetrical leaf springs 4 in Example 2 are fixedly connected to the central axis 5, and the ends extend into the slide grooves opened on the safety block 28 to form a free sliding fit with the slide grooves, so the pin 17 used to fix the end of the leaf spring 4 on the safety block 28 in Example 1 is also unnecessary. 3), the safety device in Example 1 is mainly composed of a safety block, an internal buffer compression spring, an arc plate, etc.; the safety device in Example 2 is mainly composed of a safety block, an internal buffer compression spring, an arc plate, etc., without the internal buffer compression spring in Example 1.

[0061] For Example 2, refer to Fig.21Once a fall occurs during operation, the speed of the drum wheel 6 increases due to the force of the human body falling, so that the pawl 7 on the disc of the drum wheel 6 is subjected to a large centrifugal force. The pawl 7 overcomes the tensile force of the pawl tension spring 14 and rotates around the pawl shaft 15. When the drum wheel speed reaches the locking speed, the tip of the pawl 7 will swing in the direction of the ratchet tooth groove and get stuck in the ratchet 19, achieving a one-time locking and driving the internal buffer damping device to start working, that is, the ratchet 19 rotates along the working direction with the drum wheel. The leaf spring 4 has a fixed connection with the central axis 5 at its head end and a free sliding contact with the ratchet 19 at its end. The rotation of the ratchet 19 causes the leaf spring 4 to bend, and the leaf spring 4 plays a role in hindering the rotation of the ratchet 19.

[0062] When the ratchet wheel still cannot stop rotating under the joint action of the plurality of leaf springs 4, the ratchet wheel will continue to rotate in the working direction until the safety block is in rigid contact with the arc plate, see Fig.21 The safety device composed of the safety block, the arc plate, etc. stops the drum 6, the pawl 7, and the ratchet 19 from rotating, preventing the leaf spring 4 from failing to prevent the drum 6 from stopping rotating in an extreme situation or other unexpected situations, resulting in a complete accident.

[0063] Except for the above structural differences, other structures are basically the same as those in Example 1 and will not be described again.

[0064] Example 3: Reference Figure 7 , the internal buffer tension spring and the internal buffer compression spring in Example 1 are removed to obtain Example 3. That is to say, the internal buffer damping device in Example 3 only has a leaf spring. Of course, the safety device in Example 3 is mainly composed of a safety block, an arc plate, etc., without the internal buffer compression spring in Example 1.

[0065] For Example 3, when the ratchet wheel still cannot stop rotating under the joint action of the two leaf springs 4, the ratchet wheel will continue to rotate in the working direction until the safety block and the arc plate are in rigid contact, so that the drum wheel 6, the pawl 7, and the ratchet wheel 19 stop rotating. In the event that the drum wheel cannot stop rotating, the safety device composed of the safety block, the arc plate, etc. can stop the drum wheel.

[0066] Except for the above structural differences, other structures are basically the same as those in Example 1 and will not be described again.

[0067] Embodiment 4: Embodiment 4 is obtained by removing the leaf spring in Embodiment 1. That is, the internal buffer damping device in Embodiment 4 only has an internal buffer compression spring and an internal buffer tension spring, but no leaf spring.

[0068] Except for the above structural differences, other structures are basically the same as those in Example 1 and will not be described again.

[0069] Embodiment 5: Embodiment 5 is obtained by removing the leaf spring and the inner buffer tension spring in Embodiment 1. That is, the inner buffer damping device in Embodiment 5 only has the inner buffer compression spring, but no leaf spring and inner buffer tension spring.

[0070] Except for the above structural differences, other structures are basically the same as those in Example 1 and will not be described again.

[0071] Embodiment 6: The leaf spring and the inner buffer compression spring in Embodiment 1 are removed to obtain Embodiment 5. That is, the inner buffer damping device in Embodiment 5 only has the inner buffer tension spring, but no leaf spring and inner buffer compression spring.

[0072] For Example 6, when the ratchet wheel still cannot stop rotating under the joint action of the two internal buffer tension springs, the ratchet wheel will continue to rotate in the working direction until the safety block and the arc plate are in rigid contact, so that the drum wheel 6, the pawl 7, and the ratchet wheel 19 stop rotating. In the event that the drum wheel cannot stop rotating, the safety device composed of the safety block, the arc plate, etc. can stop the drum wheel.

[0073] Except for the above structural differences, other structures are basically the same as those in Example 1 and will not be described again.

[0074] Embodiment 7: Embodiment 7 is obtained by removing the internal buffer tension spring in Embodiment 1, that is, the internal buffer damping device in Embodiment 7 only has an internal buffer compression spring and a leaf spring, but no internal buffer tension spring.

[0075] Except for the above structural differences, other structures are basically the same as those in Example 1 and will not be described again.

[0076] Embodiment 8: Embodiment 8 is obtained by removing the internal buffer compression spring in Embodiment 1, that is, the internal buffer damping device in Embodiment 8 only has an internal buffer tension spring and a leaf spring, but no internal buffer compression spring.

[0077] For Example 8, when the ratchet wheel still cannot stop rotating under the joint action of the two internal buffer tension springs, the ratchet wheel will continue to rotate in the working direction until the safety block and the arc plate are in rigid contact, so that the drum wheel 6, the pawl 7, and the ratchet wheel 19 stop rotating. In the event that the drum wheel cannot stop rotating, the safety device composed of the safety block, the arc plate, etc. can stop the drum wheel.

[0078] Except for the above structural differences, other structures are basically the same as those in Example 1 and will not be described again.

[0079] In short, this patent adopts an integral drum structure, that is, the drum cylinder part for winding the safety rope and the drum disc (upper end surface) part for fixing the pawl are an integral whole, and the winding spring disc is also fixed on the drum, so that the overall volume of the speed difference anti-fall device is relatively compact and the number of parts is relatively small. From the safety rope to the integral drum, through the pawl, ratchet and then to the frame, the entire force-bearing link has strong load-bearing capacity and impact fatigue resistance. In particular, the safety rope is sheathed on the rope column fixed inside the drum cylinder. The design is ingenious, reliable and durable, and overall avoids the safety risks caused by too many parts and difficulty in ensuring assembly accuracy.

[0080] The locking mechanism of this speed differential anti-fall device adopts a centrifugal double internal locking mechanism. The tooth grooves on the outer periphery of the ratchet are closer to the central axis than the pawls, and the ratchet is annular, so that the inner ring of the ratchet can be arranged with an internal buffer damping device, a ratchet guide device, a safety device, etc. The structure is compact and at the same time ensures reliable fixation between the ratchet and the frame.

[0081] The internal buffer damping device and the external buffer tension spring can reduce the impact force on the human body at the moment of falling and locking. The internal buffer and external buffer are combined. The internal buffer refers to the internal buffer damping device arranged on the inner side of the ratchet; the external buffer is an external buffer tension spring (diameter 30mm-80mm, length 80mm-200mm) that can withstand the impact of human falling. The external buffer tension spring is directly added between the outer end of the safety rope and the hook hung on the human safety belt, and / or between the hook end of the frame and the hook connected to the mounting point on the high building, to ensure that the anti-fall device can effectively reduce the impact damage to the human body under the premise of reliable locking.

Claims

1. A buffer type speed difference anti-fall device based on a leaf spring, comprising: A frame (23), a central shaft (5) fixed on the frame (23), a drum (6) rotatably arranged on the central shaft and located inside the frame, an inner end of a safety rope (21) wound on the drum (6) being fixed on the drum, and an outer end passing through the frame (23) and extending outward; the safety rope (21) is released when the drum (6) rotates in a working direction, and the safety rope (21) is retracted when the drum (6) rotates in a non-working direction opposite to the working direction; the locking structure including a pawl (7) and a ratchet (19) is arranged in the space between the frame (23) and the drum (6) disc; the tooth grooves on the ratchet are evenly distributed on the outer periphery of the ratchet (19), and the pawl (7) is located outside the outer periphery of the ratchet; and the pawl (7) is arranged on the outer periphery of the ratchet at a position corresponding to the drum disc. A ratchet guide device is fixed on the frame, the ratchet guide device comprises an upper baffle plate and a lower baffle plate which are in contact with the two end surfaces of the ratchet (19), and an arc plate fixed between the upper baffle plate and the lower baffle plate, the arc surface of the arc plate slidingly cooperates with the inner circumference of the ratchet; the rotation axis of the ratchet (19) is coaxial with the rotation axis of the drum wheel (6); an internal buffer damping device is provided between the central shaft (5) and the inner circumference of the ratchet (19), which can apply resistance to the rotating ratchet (19) so that the ratchet gradually stops rotating in the working direction, and the internal buffer damping device comprises a leaf spring (4), one end of the leaf spring (4) is fixed on the central shaft (5), and the other end extends into a slide groove opened on the inner circumference of the ratchet (19) and slides with the slide groove; The ratchet (7) is mounted on a ratchet shaft (15) fixed on the drum (6); a stop column (10) is provided on the drum (6) for limiting the ratchet (7) from swinging around the ratchet shaft (15) in a certain direction, i.e., a direction of stopping rotation; and an elastic element is provided between the drum (6) and the ratchet (7) for keeping the ratchet (7) in contact with the stop column (10) in a normal state. When the rotation speed of the drum wheel (6) rotating around the central axis (5) in the working direction exceeds the set locking speed, the pawl (7) rotates around the pawl rotating shaft (15) in the locking direction opposite to the stop direction under the action of the centrifugal force, and the tip of the pawl (7) is engaged in the tooth groove of the ratchet wheel (19), and the drum wheel (6) and the pawl (7) drive the ratchet wheel (19) to start rotating in the working direction. At this time, under the action of the internal buffer damping device, the drum wheel (6), the pawl (7) and the ratchet wheel (19) stop rotating after rotating a certain angle a. A safety block protruding from the inner circumference of the ratchet (19) is provided on the inner circumference of the ratchet; one end of the leaf spring (4) extends into a slide groove opened on the safety block and slides in cooperation with the slide groove; when the tip of the pawl (7) is inserted into the tooth groove of the ratchet (19), the drum (6) and the pawl (7) drive the ratchet (19) to rotate along the working direction by a certain angle b, the safety block contacts the arc plate (9), so that the drum (6), the pawl (7) and the ratchet (19) stop rotating; b≥a.

2. The buffer type speed difference anti-falling device based on leaf spring according to claim 1 is characterized in that: The internal buffer damping device also includes an internal buffer tension spring, the two ends of which are respectively connected to the safety block and the arc plate; the internal buffer tension spring applies a pulling force to the ratchet in a normal state so that the ratchet has a tendency to rotate in a non-working direction.

3. The buffer type speed difference anti-falling device based on leaf spring according to claim 1 or 2, characterized in that: The invention also comprises a safety rope recovery device including a coil spring (25) and a coil spring disk (22); the upper and lower ends of a central axis (5) passing through the drum (6) and the coil spring disk (22) are fixedly connected to a frame (23); the coil spring disk (22) is fixed to the lower part of the drum (6) and is located between the lower part of the drum (6) and the frame; one end of the coil spring (25) located in the coil spring disk (22) is fixed to the central axis (5) and the other end is fixed to the periphery of the coil spring disk (22); when an external force is applied to the outer end of the safety rope, the drum (6) and the coil spring disk (22) are pulled to rotate in the working direction through the safety rope (21), and the tightening torque of the coil spring (25) gradually increases; when the external force is released, the coil spring (25) drives the coil spring disk (22) and the drum (6) to rotate in the non-working direction, the length of the safety rope extending out of the frame gradually shortens, and the safety rope (21) is wound on the drum (6).

4. The buffer type speed difference anti-falling device based on a leaf spring as claimed in claim 1 or 2, characterized in that: It also includes an external buffer damping device, which includes an external buffer tension spring with one end connected to the frame and / or the outer end of the safety rope, and the other end of the external buffer tension spring is used to be connected to the mounting point of the buffer type speed difference anti-falling device and / or the human body's safety belt.

5. The buffer type speed difference anti-falling device based on leaf spring according to claim 1 or 2, characterized in that: The leaf spring (4) comprises a plurality of pieces, which are arranged axially symmetrically about the central axis.

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