Monorail crane stall protection device

Abstract

The invention discloses a stall protection device for a monorail crane. The speed measuring mechanism monitors the real-time speed of the monorail crane and transmits a speed signal to the controller, and the controller compares the real-time speed with a set speed. When the real-time speed exceeds the set speed, the controller sends a trigger signal to the electric cylinder, the power output shaft of the electric cylinder extends out, the check block arranged on the push rod moves, and the ratchet wheel is not blocked. The ratchet wheel rotates under the action of torsion of the torsion spring, so that the paired cams are driven to rotate relatively, the cams are close to the surface of the rail web, and the paired cams are screwed more and more tightly through sliding friction force to form a self-locking holding rail. Buffering braking is achieved by using the energy absorption steel belt, the potential safety hazard of braking slipping of an existing monorail crane is further eliminated, and therefore double safety protection of the overspeed monorail crane is achieved, the potential safety hazard of braking slipping of the existing monorail crane is effectively eliminated, and the service life of the overspeed monorail crane is prolonged. Reliable braking and effective safety protection for the monorail crane and a driver are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mine equipment, and particularly relates to a single-track crane overspeed protection device. BACKGROUND

[0002] The single-track crane vehicle is a new type of mine transportation equipment, which has been gradually popularized in coal mines. As an important modern high-efficiency auxiliary transportation equipment, the single-track crane vehicle has some advantages that cannot be compared with the small winch, the toothed rail vehicle and the trackless rubber-tyred vehicle. During the operation of the single-track crane vehicle, due to the insufficient clamping pressure of the braking system, the wear of the driving wheel and the brake block, the large inclination angle slope transportation, the wet environment leading to the wet and slippery of the I-shaped track and other reasons, the vehicle is prone to run at an uncontrollable speed. At this time, the special vehicle protection device is particularly important. However, at present, there are few studies on the single-track crane vehicle in China, and the hidden dangers are difficult to eliminate, so the safety production of coal mines cannot be guaranteed.

[0003] The single-track crane overspeed protection device provided by the present application effectively eliminates the safety hazards of the current single-track crane brake slip, and realizes reliable braking and effective safety protection for the single-track crane vehicle and the driver.

[0004] The single-track crane overspeed protection device provided by the present application effectively eliminates the safety hazards of the current single-track crane brake slip, and realizes reliable braking and effective safety protection for the single-track crane vehicle and the driver.

[0005] Specifically, it further comprises: an upper shaft sleeve and a lower shaft sleeve; an upper through hole is formed in the top surface of the frame, and a lower through hole is formed in the bottom surface of the frame; the upper shaft sleeve is arranged in the upper through hole; the lower shaft sleeve is arranged in the lower through hole; the first end of the camshaft penetrates into the upper shaft sleeve, and the second end of the camshaft penetrates into the lower shaft sleeve.

[0006] Specifically, it further comprises: a push rod supporting seat; the push rod supporting seat is arranged on the frame; the push rod penetrates through the central through hole of the push rod supporting seat.

[0007] Specifically, the speed measuring mechanism comprises: a left roller, a right roller, a left support, a right support, a base and a spring; the left roller and the right roller are arranged on the two sides of the track respectively, the left roller is arranged in the left support, the right roller is arranged in the right support, an encoder is arranged on the rotating shaft of the left roller and / or the right roller, the signal output end of the encoder is in communication connection with the signal input end of the controller, the lower ends of the left support and the right support are respectively in limited rotary connection with the left support seat and the right support seat on the base, the spring connects the left support and the right support, and the base is connected with the frame.

[0008] Specifically, the left support seat and the right support seat are both in cylindrical structure, the lower ends of the left support and the right support are both in rotating shaft structure, and the two ends of the rotating shaft structure are in flange part; the middle part of the rotating shaft structure is arranged in the cylindrical structure.

[0009] Specifically, the cylindrical structure is composed of an upper half cylinder and a lower half cylinder which are detachably connected.

[0010] Specifically, the upper half cylinder and the lower half cylinder are detachably connected through bolts.

[0011] Specifically, it further comprises: a first connecting box body and a second connecting box body; the two ends of the first connecting box body are connected with the base and the frame respectively; the two ends of the second connecting box body are connected with the frame and the connecting end of the energy-absorbing steel belt respectively; the first connecting box body and the second connecting box body are both hung in the track.

[0012] One or more technical solutions provided in the application have at least the following technical effects or advantages:

[0013] The real-time speed of the monorail crane vehicle is monitored by a speed measuring mechanism and the speed signal is transmitted to the controller, and the real-time speed is compared with the set speed by the controller. When the real-time speed exceeds the set speed, the brake is triggered, the controller sends a trigger signal to the electric cylinder, the power output shaft of the electric cylinder is extended, the stop block arranged on the push rod moves, and the ratchet wheel is not blocked. The ratchet wheel rotates under the action of the torsional spring torque, thereby driving the pair of cams to rotate relatively, so that the cams are close to the rail waist surface, and the sliding friction makes the pair of cams rotate tighter to form self-locking and hold the rail. By using the energy-absorbing steel belt, the buffer brake is realized, and the safety hidden danger of the current monorail crane brake slip is further eliminated, thereby realizing the double safety protection of the overspeed monorail crane vehicle, effectively eliminating the safety hidden danger of the current monorail crane brake slip, and realizing reliable brake and effective safety protection of the monorail crane vehicle and the driving personnel. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 A perspective view of the monorail crane overspeed protection device provided for the embodiment of the present application is provided.

[0015] Figure 2 A front view of the monorail crane overspeed protection device provided for the embodiment of the present application is provided.

[0016] Figure 3 A structure schematic view of the brake driving mechanism in the monorail crane overspeed protection device provided for the embodiment of the present application in the first perspective is provided.

[0017] Figure 4 A structure schematic view of the brake driving mechanism in the monorail crane overspeed protection device provided for the embodiment of the present application in the second perspective is provided.

[0018] Figure 5 A local enlarged view of the brake driving mechanism in the monorail crane overspeed protection device provided for the embodiment of the present application is provided.

[0019] Figure 6 A bottom view of the monorail crane overspeed protection device provided for the embodiment of the present application in a non-braking state is provided.

[0020] Figure 7 A bottom view of the monorail crane overspeed protection device provided for the embodiment of the present application in a braking state is provided.

[0021] Figure 8 A top view of the monorail crane overspeed protection device provided for the embodiment of the present application in a braking state is provided.

[0022] Figure 9 A structure schematic view of the energy-absorbing buffer brake mechanism in the monorail crane overspeed protection device provided for the embodiment of the present application is provided.

[0023] Figure 10The structure schematic view of the speed measuring mechanism 13 in the monorail crane stall protection device provided by the embodiment of the present application is shown in the figure;

[0024] Wherein, 1-cam group, 2-camshaft, 3-ratchet group, 4-electric cylinder, 5-push rod, 6-stop block, 7-yoke, 8-yoke shaft, 9-torsion spring, 10-torsion spring hook, 11-torsion spring hook pin, 12-frame, 13-speed measuring mechanism, 14-monorail crane vehicle, 15-rail, 16-push rod support seat, 17-left roller, 18-right roller, 19-left support, 20-right support, 21-base, 22-spring, 23-encoder, 24-cylinder structure, 25-flange part, 26-center roller, 27-energy absorption steel belt, 28-press roller group, 29-steel belt box, 30-hanging, 31-first connecting box, 32-second connecting box. DETAILED DESCRIPTION

[0025] The embodiment of the present application provides a monorail crane stall protection device, effectively eliminates the safety hazard of the current monorail crane brake slip, and realizes reliable brake and effective safety protection for the monorail crane vehicle and the driver.

[0026] In order to better understand the above technical solutions, the above technical solutions will be described in detail below in combination with the drawings in the specification and specific embodiments.

[0027] As Figures 1-9As shown, the single-track crane stall protection device provided by the embodiment of the application comprises a cam set 1, a cam shaft 2, a ratchet set 3, an electric cylinder 4, a push rod 5, a stop block 6, a yoke 7, a yoke shaft 8, a torsional spring 9, a torsional spring hook 10, a torsional spring hook pin 11, a frame 12, a speed measuring mechanism 13, a controller, a center roller 26, an energy-absorbing steel belt 27, a compression roller set 28, and a steel belt box 29; the cam set 1 is arranged on both sides of a track 15; the first end of the cam shaft 2 penetrates into the cam of the cam set 1, and the second end of the cam shaft 2 penetrates into the ratchet of the ratchet set 3; the torsional spring hook 10 is arranged on the frame 12; the torsional spring hook pin 11 is arranged on the ratchet; the torsional spring 9 is sleeved on the cam shaft 2, the first end of the torsional spring 9 is arranged in the torsional spring hook 10, and the second end of the torsional spring 9 is arranged on the torsional spring hook pin 11; the push rod 5 is connected with the front end of the power output shaft of the electric cylinder 4; the stop block 6 is arranged on the push rod 5; the yoke shaft 8 is arranged on the frame 12; the yoke shaft 8 penetrates into the center through hole of the yoke 7; the yoke 7 can rotate around the yoke shaft 8, the first end of the yoke 7 is limited by the stop block 6, and the second end of the yoke 7 limits the ratchet; the speed measuring mechanism 13 is connected with the frame 12; the signal output end of the speed measuring mechanism 13 is in communication connection with the signal input end of the controller, and the signal output end of the controller is in communication connection with the signal input end of the electric cylinder 4. The center roller 26, the energy-absorbing steel belt 27, and the compression roller set 28 are all arranged in the steel belt box 29; the energy-absorbing steel belt 27 is wound on the center roller 26, and the connecting end of the energy-absorbing steel belt 27 penetrates out of the first end of the steel belt box 29 through the compression roller set 28 and is connected with the frame 12. The steel belt box 29 is hung in the track 15 through a hanging part 30; the second end of the steel belt box 29 is used for being connected with a single-track crane vehicle 14. Among them, the speed measuring mechanism 13 is used for monitoring the forward speed of the single-track crane vehicle 14 in real time; the controller is used for controlling the power output shaft of the electric cylinder 4 to stretch out to trigger braking when the forward speed of the single-track crane vehicle 14 is greater than a set speed; and the frame 12 is used for bearing the force conducted during braking. When the cam is not braking, the power output shaft of the electric cylinder 4 is retracted, the first end of the yoke 7 is limited by the stop block 6, and the second end of the yoke 7 blocks a tooth of the ratchet. Although the torsional spring 9 has exerted a torsional force on the ratchet, the ratchet cannot rotate in the direction of the torsional force, and there is a gap between the cam and the track 15; when the controller controls the power output shaft of the electric cylinder 4 to stretch out, the stop block 6 moves forward, the first end of the yoke 7 also rotates, the second end of the yoke 7 is separated from the ratchet, the ratchet rotates under the action of the torsional force of the torsional spring 9, the cam is driven to rotate by the cam shaft 2, the cam is tightly attached to the track waist surface of the track 15 to realize braking. In addition, during the braking process of the cam set 1 on the track 15, the energy-absorbing steel belt 27 will be pulled out, and the energy-absorbing steel belt 27 absorbs the kinetic energy of the single-track crane vehicle 14 due to plastic deformation when the energy-absorbing steel belt 27 is pulled out, so as to realize buffer braking.

[0028] The structure of the cam set 1 is described in detail, the cam set 1 is composed of two pairs of front and rear cams, each pair of cams is composed of two cams which are symmetrical to each other with the center of the track 15. In this case, the single-track crane stall protection device provided by the embodiment of the application specifically comprises: a left front cam, a left rear cam, a right front cam, a right rear cam, a left front cam shaft, a left rear cam shaft, a right front cam shaft, a right rear cam shaft, a left front ratchet wheel, a left rear ratchet wheel, a right front ratchet wheel, a right rear ratchet wheel, an electric cylinder 4, a push rod 5, a stop block 6, a left front shift fork, a left rear shift fork, a right front shift fork, a right rear shift fork, a left front shift fork shaft, a left rear shift fork shaft, a right front shift fork shaft, a right front shift fork shaft, a left front torsional spring, a left rear torsional spring, a right front torsional spring, a right rear torsional spring, a left front torsional spring hook, a left rear torsional spring hook, a right front torsional spring hook, a right rear torsional spring hook, a left front torsional spring hook pin, a left rear torsional spring hook pin, a right front torsional spring hook pin, a right rear torsional spring hook pin, a frame 12, a speed measuring mechanism 13, a controller, a center roller 26, an energy-absorbing steel belt 27, a compression roller set 28 and a steel belt box 29; the structure of the front pair of cams is that the left front cam and the right front cam are symmetrically arranged on the two sides of the track 15; the first end of the left front cam shaft penetrates into the left front cam, and the second end of the left front cam shaft penetrates into the left front ratchet wheel; the left front torsional spring hook is arranged on the frame 12; the left front torsional spring hook pin is arranged on the left front ratchet wheel; the left front torsional spring is sleeved on the left front cam shaft, the first end of the left front torsional spring is arranged in the left front torsional spring hook, and the second end of the left front torsional spring is arranged on the left front torsional spring hook pin; the first end of the right front cam shaft penetrates into the right front cam, and the second end of the right front cam shaft penetrates into the right front ratchet wheel; the right front torsional spring hook is arranged on the frame 12; the right front torsional spring hook pin is arranged on the right front ratchet wheel; the right front torsional spring is sleeved on the right front cam shaft, the first end of the right front torsional spring is arranged in the right front torsional spring hook, and the second end of the right front torsional spring is arranged on the right front torsional spring hook pin; the push rod 5 is connected with the front end of the power output shaft of the electric cylinder 4; the stop block 6 is arranged on the push rod 5; the left front shift fork shaft is arranged on the frame 12; the left front shift fork shaft penetrates into the center through hole of the left front shift fork; the first end of the left front shift fork is limited by the stop block 6, and the second end of the left front shift fork limits the left front ratchet wheel; the right front shift fork shaft is arranged on the frame 12; the right front shift fork shaft penetrates into the center through hole of the right front shift fork; the first end of the right front shift fork is limited by the stop block 6, and the second end of the right front shift fork limits the right front ratchet wheel; the structure of the rear pair of cams is the same as that of the front pair of cams, which will not be described here; the speed measuring mechanism 13 is connected with the frame 12; the signal output end of the speed measuring mechanism 13 is in communication connection with the signal input end of the controller, and the signal output end of the controller is in communication connection with the signal input end of the electric cylinder 4. Facing the advancing direction of the single-track crane locomotive 14 and looking from top to bottom, the direction of the torsional force of the right torsional spring applied on the right cam is along the counterclockwise direction, and the direction of the torsional force of the left torsional spring applied on the left cam is along the clockwise direction; after the brake is triggered, because the gap between the outer contour surface of the cam and the rail waist surface of the track 15 becomes smaller and smaller in the rotating process of the cam, until the cam is tightly attached to the track 15, then the sliding friction force is generated on the cam and the rail waist surface of the track 15, the friction force makes the cam continue to rotate, and the cam is more and more tightly, until the cam moves forward and stops, and the brake is completed.

[0029] In order to improve the stability of the structure of the single-track hoist stall protection device provided by the embodiment of the application, an upper shaft sleeve and a lower shaft sleeve are further included; an upper through hole is formed in the top surface of the frame 12, and a lower through hole is formed in the bottom surface of the frame 12; the upper shaft sleeve is arranged in the upper through hole; the lower shaft sleeve is arranged in the lower through hole; the first end of the camshaft 2 penetrates the upper shaft sleeve, and the second end of the camshaft 2 penetrates the lower shaft sleeve.

[0030] In order to further improve the stability of the structure of the single-track hoist stall protection device provided by the embodiment of the application, a push rod support seat 16 is further included; the push rod support seat 16 is arranged on the frame 12; the push rod 5 penetrates the central through hole of the push rod support seat 16.

[0031] The structure of the speed measuring mechanism 13 is specifically described as follows. Figure 10 As shown in the figure, the speed measuring mechanism 13 includes a left roller 17, a right roller 18, a left support 19, a right support 20, a base 21, and a spring 22; the left roller 17 and the right roller 18 are arranged on the two sides of the track 15 respectively, the left roller 17 is arranged in the left support 19; the right roller 18 is arranged in the right support 20; an encoder 23 is arranged on the rotating shaft of the left roller 17 and / or the right roller 18; the signal output end of the encoder 23 is in communication connection with the signal input end of the controller; the lower ends of the left support 19 and the right support 20 are respectively in limited rotary connection with the left support and the right support on the base 21; the spring 22 connects the left support 19 and the right support 20; the base 21 is connected with the frame 12. The spring 22 in the speed measuring mechanism 13 pulls the left support 19 and the right support 20 on the two sides of the track 15, so that the left roller 17 and the right roller 18 on the two sides of the track 15 are tightly attached to the track waist surface of the track 15, the rotation is transmitted to the encoder 23 through the rotating shaft, and the speed is measured.

[0032] The structure that the lower ends of the left support 19 and the right support 20 are respectively in limited rotary connection with the left support and the right support on the base 21 is specifically described as follows. The left support and the right support both have a cylindrical structure 24; the lower ends of the left support 19 and the right support 20 are both in rotating shaft structure, and the two ends of the rotating shaft structure are in flange structure 25; the middle part of the rotating shaft structure is arranged in the cylindrical structure 24. The inner diameter of the cylindrical structure 24 is greater than the outer diameter of the middle part and smaller than the outer diameter of the flange structure 25, so that the limited rotary connection between the support and the support is realized through the flange structure 25, and the axial displacement of the left support 19 and the right support 20 during movement is prevented, so as to improve the accuracy of speed measurement.

[0033] The structure of the cylindrical structure 24 is specifically described as follows. The cylindrical structure 24 is composed of an upper half-cylinder and a lower half-cylinder which are detachably connected.

[0034] Further, the upper half-cylinder and the lower half-cylinder are detachably connected by bolts. In use, the middle part of the rotating shaft structure at the lower end of the support is placed in the lower half-cylinder, and then the upper half-cylinder is buckled to be connected to the lower half-cylinder by bolts. The middle part of the rotating shaft structure at the lower end of the support can rotate in the through hole formed by the upper half-cylinder and the lower half-cylinder.

[0035] In order to further improve the stability of the monorail crane stall protection device structure provided by the embodiment of the present application, a first connecting box 31 and a second connecting box 32 are further included; the two ends of the first connecting box 31 are connected to the base 21 and the frame 12 respectively; the two ends of the second connecting box 32 are connected to the frame 12 and the connecting end of the energy-absorbing steel belt 27 respectively; the first connecting box 31 and the second connecting box 32 are both hung in the track 15.

[0036] It should be noted that in actual application, one set of the monorail crane stall protection device provided by the embodiment of the present application is symmetrically installed at the head and tail of the monorail crane vehicle 14 respectively, and is used for protection when the monorail crane vehicle 14 runs uphill and downhill.

[0037] The working principle of the monorail crane stall protection device provided by the embodiment of the present application is described below.

[0038] When the monorail crane vehicle 14 advances, the left roller 17 and the right roller 18 roll, and the rotating shaft rotates synchronously. The encoder 23 detects the rotating speed of the rotating shaft and transmits the rotating speed signal to the controller. The controller calculates the advancing speed of the monorail crane vehicle 14 according to the rotating speed signal, and controls the power output shaft of the electric cylinder 4 to extend when the advancing speed of the monorail crane vehicle 14 is greater than a set value (3.5 m / s in this embodiment). The stop block 6 provided on the push rod 5 moves forward, and the first end of the fork 7 also rotates, and the second end of the fork 7 is separated from the ratchet wheel. The ratchet wheel rotates under the action of the torsional force of the torsional spring 9, and the cam rotating shaft is driven by the cam shaft 2 to be tightly attached to the rail waist surface to realize self-locking and clamping braking. At the same time, the energy-absorbing steel belt 27 is pulled out during the braking process of the cam set 1. The energy-absorbing steel belt 27 absorbs the kinetic energy of the monorail crane vehicle 14 due to plastic deformation when it is pulled out, thereby realizing buffer braking.

[0039] In summary, the embodiment of the present application provides a monorail crane stall protection device which realizes overspeed braking through automatic control by utilizing the functions of cam self-locking and metal plastic deformation energy absorption. When the running speed of the monorail crane vehicle 14 is out of control (greater than the set maximum speed), the pair of cams arranged on both sides of the track 15 are automatically triggered to rotate and self-lock on the track 15, and the energy absorption steel belt 27 is pulled out. The plastic deformation of different sections continuously occurs in the bending process of the steel belt, so as to absorb the kinetic energy of the monorail crane vehicle 14 running, thereby realizing the buffer braking of the monorail crane vehicle 14, and further realizing the double safety protection of the overspeed monorail crane vehicle 14. The safety hidden danger of the current monorail crane brake slip is effectively eliminated, and reliable braking and effective safety protection of the monorail crane vehicle and the driving personnel are realized.

[0040] The part not described in the embodiment of the present application is the known technology of the person skilled in the art. Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced by equivalents without departing from the purpose and scope of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. A monorail crane stall protection device, characterized in that: include: Cam group, camshaft, ratchet group, electric cylinder, push rod, block, shift fork, shift fork shaft, torsion spring, torsion spring hook, torsion spring hanging pin, frame, speed measuring mechanism, controller, center roller, energy-absorbing steel belt, pressure roller group and steel belt box; the cam group is arranged on both sides of the track; the first end of the camshaft penetrates into the cam of the cam group, and the second end of the camshaft penetrates into the ratchet of the ratchet group; the torsion spring hook is arranged on the frame; the torsion spring hanging pin is arranged on the ratchet; the torsion spring is sleeved on the camshaft, the first end of the torsion spring is arranged in the torsion spring hook, and the second end of the torsion spring is arranged on the torsion spring hanging pin; the push rod is connected to the front end of the power output shaft of the electric cylinder; the block is arranged on the push rod; the shift fork shaft is arranged On the frame; the shift fork shaft passes through the central through hole of the shift fork; the first end of the shift fork is limited by the block, and the second end of the shift fork limits the ratchet; the speed measuring mechanism is connected to the frame; the signal output end of the speed measuring mechanism is communicatively connected with the signal input end of the controller, and the signal output end of the controller is communicatively connected with the signal input end of the electric cylinder; the center roller, the energy-absorbing steel belt, and the pressure roller group are all arranged in the steel belt box; the energy-absorbing steel belt is wound around the center roller, and the connecting end of the energy-absorbing steel belt passes through the first end of the steel belt box through the pressure roller group and is connected to the frame; the steel belt box is hung in the track by hanging; the second end of the steel belt box is used to connect with the monorail crane.

2. The monorail crane stall protection device according to claim 1, characterized in that: Also includes: An upper sleeve and a lower sleeve; an upper through hole is opened on the top surface of the frame, and a lower through hole is opened on the bottom surface of the frame; the upper sleeve is arranged in the upper through hole; the lower sleeve is arranged in the lower through hole; the first end of the camshaft passes through the upper sleeve, and the second end of the camshaft passes through the lower sleeve.

3. The monorail crane stall protection device according to claim 1, characterized in that: Also includes: A push rod support seat; the push rod support seat is arranged on the frame; the push rod passes through the central through hole of the push rod support seat.

4. The monorail crane stall protection device according to claim 1, characterized in that: The speed measuring mechanism includes: a left roller, a right roller, a left bracket, a right bracket, a base and a spring; the left roller and the right roller are respectively arranged on both sides of the track, the left roller is arranged in the left bracket; the right roller is arranged in the right bracket; an encoder is provided on the rotating shaft of the left roller and / or the right roller; the signal output end of the encoder is communicatively connected with the signal input end of the controller; the lower ends of the left bracket and the right bracket are respectively connected to the left support and the right support on the base for limited rotation; the spring connects the left bracket and the right bracket; and the base is connected to the frame.

5. The monorail crane stall protection device according to claim 4, characterized in that: The left support and the right support both have cylindrical structures; the lower ends of the left support and the right support are both shaft structures, and both ends of the shaft structures are flange parts; the middle part of the shaft structure is arranged in the cylindrical structure.

6. The monorail crane stall protection device according to claim 5, characterized in that: The cylindrical structure consists of an upper semi-cylinder and a lower semi-cylinder which are detachably connected.

7. The monorail crane stall protection device according to claim 6, characterized in that: The upper semi-cylinder and the lower semi-cylinder are detachably connected by bolts.

8. The monorail crane stall protection device according to claim 4, characterized in that: Also includes: A first connecting box and a second connecting box; the two ends of the first connecting box are respectively connected to the base and the frame; the two ends of the second connecting box are respectively connected to the frame and the connection end of the energy-absorbing steel belt; the first connecting box and the second connecting box are both hung in the track.

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