Automatic walking mechanism of suspension grouting bridge fabrication machine

Abstract

The invention discloses an automatic walking mechanism of a suspension grouting bridge fabrication machine, which belongs to the technical field of bridge construction and comprises two groups of walking units arranged below a main beam. The walking unit comprises a rear change gear set, a rear supporting wheel set, a front supporting change gear integrated structure and a hydraulic motor transmission mechanism which are sequentially and fixedly arranged on the walking beam from back to front. The upper end of the hydraulic motor transmission mechanism is meshed with the lower end face of the main beam through a gear and a rack for driving the walking beam and the main beam to move; the upper end of the rear supporting wheel set abuts against the main beam bottom plate and is used for supporting the main beam to walk. The upper end of the rear hanging wheel set is hung on the main beam bottom plate and used for hanging the walking beam on the main beam to walk; the front supporting change gear integrated structure comprises a front supporting wheel and a front change gear; the front supporting wheels are used for supporting the main beam to walk together with the rear supporting wheel sets; the front change gear is used for hanging the walking beam on the main beam to walk together with the rear change gear set. The device has the advantages that the device can automatically walk, the operation is simple, the automation and safety are improved, the construction efficiency is improved, and the construction cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge construction, and more specifically relates to an automatic walking mechanism of a suspended grouting bridge-building machine. Background Art

[0002] A bridge-building machine is a mechanical equipment specially used for building bridges. It has multiple functions such as hoisting, construction, and movement. It can carry out bridge construction under various complex terrain conditions, improve construction efficiency, and ensure construction safety. The suspended grouting bridge-building machine can be used for cast-in-place operations of continuous beams to realize aerial bridge construction. It is mainly composed of multiple systems such as mobile brackets, templates, electric control hydraulics, safety protection, informationization, and intelligent control. It can be applied to the construction of continuous beams with different spans and sections. The existing suspended grouting bridge-building machine walking mechanism adopts the method of re-laying a new running beam on the top of the cast beam body, and then guiding the main beam to the new running beam for the main beam to walk, and dismantling the old running beam. The newly laid running beam has problems such as inaccurate docking position and non-colinearity with the original running beam. The construction process is relatively cumbersome and will increase additional equipment consumption. Therefore, how to provide an automatic walking mechanism for a suspended grouting bridge-building machine is a problem that technicians in this field need to solve urgently. Summary of the invention

[0003] In view of this, the present invention provides an automatic walking mechanism of a suspended grouting bridge-building machine, which is mainly used to solve the problems of the existing suspended grouting bridge-building machine such as inconvenient and unstable walking and the lack of synchronization with the movement of the running beam.

[0004] In order to achieve the above object, the present invention adopts the following technical solution:

[0005] The automatic walking mechanism of a suspended grouting bridge-building machine comprises two groups of walking units respectively arranged under the main beam; the walking unit comprises a rear hanging wheel group, a rear supporting wheel group, a front supporting hanging wheel integrated structure and a hydraulic motor transmission mechanism which are sequentially arranged on the walking beam from back to front; the lower end of the hydraulic motor transmission mechanism is fixedly connected to the walking beam, and the upper end is connected to the lower end surface of the main beam through gear and rack meshing transmission connection, so as to drive the walking beam and the main beam to move; the lower end of the rear supporting wheel group is fixedly connected to the walking beam, and the upper end abuts against the bottom plate of the main beam, so as to support the main beam to walk; the lower end of the rear hanging wheel group is fixedly connected to the walking beam, and the upper end is suspended on the bottom plate of the main beam, so as to hang the walking beam on the main beam for walking; the front supporting hanging wheel integrated structure comprises a front supporting wheel and a front hanging wheel; the front supporting wheel is used to support the main beam for walking together with the rear supporting wheel group; the front hanging wheel is used to hang the walking beam on the main beam for walking together with the rear hanging wheel group.

[0006] Furthermore, a rear anchor seat and a front anchor seat are also provided on the walking beam; the rear anchor seat and the front anchor seat of the walking beam bolt the walking beam to the bridge body through anchor bolts to prevent the walking beam from moving when the main beam moves.

[0007] Furthermore, a front support seat is fixedly provided on the walking beam and is arranged in front of the front support hanging wheel integrated structure; during bridge construction, a pad is arranged above the front support seat to support the main beam; an avoidance groove is also arranged at the center position of the front support seat to avoid the rack.

[0008] Furthermore, two support wheel tracks are arranged on both sides of the lower end surface of the main beam bottom plate, and the upper end of the rear support wheel group and the upper end of the front support wheel are both in contact with the support wheel tracks.

[0009] Furthermore, the rear supporting wheel group includes a rear supporting wheel box and two groups of rear supporting wheels; the lower end of the rear supporting wheel box is bolted to the walking beam; the two groups of rear supporting wheels are respectively rotatably arranged inside the rear supporting wheel box, and the upper ends are respectively abutted against two supporting wheel tracks.

[0010] Furthermore, the rear wheel group includes a rear wheel box and two groups of rear wheels; the two groups of rear wheels are respectively arranged on the outer extension of the main beam bottom plate; the lower end of the rear wheel box is fixedly connected to the walking beam and is rotatably connected to the two groups of rear wheels.

[0011] Furthermore, the front supporting wheel integrated structure includes a wheel box base, two groups of front supporting wheels and two groups of telescopic mechanisms; the lower end surface of the wheel box base is fixedly connected to the walking beam; the upper ends of the two groups of front supporting wheels are respectively abutted against two supporting wheel tracks, and the middle parts are respectively rotatably connected to the wheel box base; the two groups of telescopic mechanisms are respectively fixed at both ends of the wheel box base and clamped on both sides of the main beam.

[0012] Furthermore, the telescopic mechanism includes two front hanging wheels, a rotating shaft, an adjusting bolt, an adjusting base, an adjusting chamber and a spring; the lower end of the adjusting chamber is fixedly connected to the wheel box base; a base plate is provided in the middle of the adjusting chamber; the lower end of the adjusting base is provided above the base plate; the upper end of the spring abuts against the lower wall of the adjusting base, and the lower end abuts against the base plate; the adjusting bolt passes through the upper and lower walls of the base plate, spring, and the adjusting base, and is fixed by a nut above the upper wall of the adjusting base after adjustment.

[0013] Furthermore, the hydraulic motor transmission mechanism includes a hydraulic motor fixing seat, a hydraulic motor and a gear; the hydraulic motor is fixed above the walking beam through the hydraulic motor fixing seat; the output shaft of the hydraulic motor is coaxially fixedly connected with the gear; a rack is fixed at the center position of the bottom plate of the main beam; the gear is meshed with the rack for transmission.

[0014] The beneficial effects of the present invention are:

[0015] The present invention is mainly aimed at the construction of highway and railway bridges, and an automatic walking mechanism of a suspended grouting bridge-building machine is arranged. By combining the movement of the main beam with the movement of the walking beam, the suspended grouting bridge-building machine can move synchronously with its own track. The hydraulic motor can achieve stepless speed regulation within a wide range, and the speed regulation process is smooth, without impact, and safe to use. The equipment can move autonomously, the operation is simple, the automation and safety are improved, the construction efficiency is improved, and the construction cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0018] Figure 2 for Figure 1 Middle AA cross section.

[0019] Figure 3 for Figure 1 Middle BB cross section.

[0020] Figure 4 for Figure 1 Middle CC cross-section.

[0021] Figure 5 for Figure 1 Middle DD cross-section.

[0022] Figure 6 for Figure 1 Middle EE cross section.

[0023] Figure 7 It is a side view of the telescopic mechanism in the present invention.

[0024] Figure 8 It is the front view of the telescopic mechanism in the present invention.

[0025] Among them, in the figure:

[0026] 1-main beam; 2-rear anchor beam one; 3-rear support leg; 4-rear anchor beam two; 5-rear hanging wheel group; 6-rear support wheel group; 7-rear anchor seat of walking beam; 8-hydraulic motor transmission mechanism; 9-front support hanging wheel integrated mechanism; 10-front support seat; 11-front anchor seat of walking beam; 12-front support leg; 13-support wheel track; 14-rack; 15-gear; 16-hydraulic motor; 17-walking beam; 18-rotating shaft; 19-adjusting bolt; 20-adjusting base; 21-adjusting cavity; 22-spring; 23-base plate. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The existing suspended cast-in-place bridge-building machine is composed of multiple systems such as a mobile support, a bridge casting template, an electric control hydraulic system, safety protection, information technology, and intelligent control, and can be applied to the construction of continuous beams of different spans and sections. The mobile support is the main bearing structure of the entire bridge-building machine, supporting other systems to walk along the walking beam set above the built bridge body. A main beam is set on each side of the upper end of the mobile support, and the walking mechanism is set below the mobile support to drive the mobile support to move along the length direction of the bridge through the driving wheel support device.

[0029] Please refer to the attached Figure 1-8 The present invention provides an automatic walking mechanism of a suspended grouting bridge-building machine, comprising two groups of walking units respectively arranged under a main beam 1.

[0030] The main beam 1 of the suspended bridge-building machine involved in the present invention is a box-type structure, and both sides of the bottom plate of the main beam 1 extend outward to form an extension; a front leg 12, a rear leg 3 and a walking unit are arranged below the main beam 1; the front leg 12 and the rear leg 3 are both provided with a hydraulic jack inside for lifting the main beam 1; the front leg 12 moves to the front end of the travel on the T-shaped track arranged on the main beam 1 through a hanging wheel, and is hinged with the main beam 1, and is fixedly connected by a latch after moving into position, and is suspended below during the bridge pouring construction, and the bridge After the beam is cast and cured, the hydraulic jack at the bottom is supported on the bridge body to support the main beam 1 for the movement of the walking beam 17; the rear support leg 3 is arranged at the rear end of the main beam 1, and a connecting seat is arranged between the main beam 1 and the main beam 1, and is fixed to the lower end surface of the main beam 1 by flange bolts; the rear end of the main beam 1 is also provided with a rear anchor beam 1 2 and a rear anchor beam 2 4 for anchoring with the beam surface, which are fixed to the bridge body by anchor bolts, and the rear end of the main beam 1 is fixed during the main casting construction of the bridge to prevent the main beam 1 from overturning due to the force of the front casting construction.

[0031] The main beam 1 is supported at two points. When the main beam 1 is stationary and the walking beam 17 moves, it is supported by the front support legs 12 and the rear support legs 3. The hydraulic jack is supported on the bridge body to lift the main beam 1 and limit the main beam 1 on the bridge body. When the main beam 1 moves, the hydraulic jack is retracted to make the main beam 1 fall on the walking unit, driving the main beam 1 to move forward and backward along the walking beam 17.

[0032] The walking unit in the present invention includes a rear hanging wheel group 5, a rear supporting wheel group 6, a front supporting hanging wheel integrated structure 9 and a hydraulic motor transmission mechanism 8 which are arranged on the walking beam 17 from back to front in sequence; the rear supporting wheel group 6 and the front supporting hanging wheel integrated structure 9 are bolted to the rear end and front end of the walking beam 17; the hydraulic motor transmission mechanism 8 is arranged behind the front supporting hanging wheel integrated structure 9, the lower end of which is fixedly connected to the walking beam 17, and the upper end is movably connected to the lower end surface of the main beam 1.

[0033] After the hydraulic jacks of the front legs 12 and the rear legs 3 are recovered, the gravity of the main beam 1 is applied to the rear supporting wheel group 6 and the front supporting hanging wheel integrated structure 9, so that the wheels roll along the lower end surface of the main beam 1, and the main beam 1 is driven by the hydraulic motor transmission mechanism 8 to move forward; when it moves to the specified position, the hydraulic jack is lowered to fix the main beam 1 on the bridge body, and the gravity of the main beam 1 is re-applied to the front legs 12 and the rear legs 3, loosening the bolting of the walking beam 17. Due to the action of the rear hanging wheel group 5 and the front supporting hanging wheel integrated structure 9, the walking beam 17 moves forward to the next working position under the driving force of the hydraulic motor transmission mechanism 8.

[0034] The walking beam 17 is also provided with a walking beam rear anchor seat 7 and a walking beam front anchor seat 11; when the main beam 1 moves along the walking beam 17, the walking beam rear anchor seat 7 and the walking beam front anchor seat 11 bolt the walking beam 17 to the bridge body through anchor bolts to prevent the walking beam 17 from moving.

[0035] The walking beam 17 is also fixed with a front support seat 10, which is arranged in front of the front support wheel integrated structure 9. Under the walking condition, the upper end surface is at a certain distance from the main beam 1. During the bridge construction, a cushion block is arranged above the front support seat 10 to support the main beam 1 to prevent the main beam 1 from being damaged by the force during the construction. The center position of the front support seat 10 is also provided with an avoidance groove to avoid the movement of the rack 14 described below.

[0036] Two support wheel tracks 13 are arranged on both sides of the lower end surface of the bottom plate of the main beam 1; the rear support wheel group 6 is located at the rear end of the walking beam 17, and includes a rear support wheel box and two groups of rear support wheels; the lower end of the rear support wheel box is bolted to the walking beam 17; the two groups of rear support wheels are respectively rotatably arranged inside the rear support wheel box, and the upper ends are respectively abutted on the two support wheel tracks 13, and travel along the support wheel tracks 13.

[0037] The rear hanging wheel group 5 is arranged behind the rear supporting wheel group 6, including a rear hanging wheel box and two groups of rear hanging wheels; the two groups of rear hanging wheels are respectively arranged on the extension of the bottom plate of the main beam 1; the lower end of the rear hanging wheel box is fixedly connected to the walking beam 17, and is rotatably connected to the two groups of rear hanging wheels, so that the rear hanging wheel group 5 is suspended on the bottom plate of the main beam 1 when the walking beam 17 moves.

[0038] The front supporting wheel integrated structure 9 is arranged at the front end of the walking beam 17, including a wheel box base, two groups of front supporting wheels and two groups of telescopic mechanisms; the lower end surface of the wheel box base is fixedly connected to the walking beam 17; the upper ends of the two groups of front supporting wheels are respectively abutted on the two supporting wheel rails 13, and the middle parts are respectively rotatably connected to the wheel box base; the two groups of telescopic mechanisms are respectively fixed at both ends of the wheel box base and clamped on both sides of the main beam 1; the telescopic mechanism includes two front hanging wheels, a rotating shaft 18, an adjusting bolt 19, an adjusting base 20, an adjusting cavity 21 and a spring 22; the lower end of the adjusting cavity 21 is connected to the wheel box base Fixed connection; a base plate 23 is provided in the middle of the adjustment chamber 21; the lower end of the adjustment base 20 is arranged above the base plate 23; the upper end of the spring 22 abuts against the lower wall of the adjustment base 20, and the lower end abuts against the base plate 23; the adjustment bolt 19 passes through the base plate 23, the spring 22, and the upper and lower walls of the adjustment base 20, and is fixed by a nut above the upper wall of the adjustment base 20 after adjustment; two front hanging wheels are rotatably arranged on the adjustment base 20 through the rotating shaft 18; the adjustment base 20 can be adjusted to move up and down inside the adjustment chamber 21 by adjusting the adjustment bolt 19.

[0039] The hydraulic motor transmission mechanism 8 includes a hydraulic motor fixing seat, a hydraulic motor 16 and a gear 15; the hydraulic motor 16 is fixedly mounted above the walking beam 17 through the hydraulic motor fixing seat; the output shaft of the hydraulic motor 16 is coaxially fixedly connected with the gear 15; a rack 14 is fixedly mounted at the center of the bottom plate of the main beam 1; the gear 15 is meshed with the rack 14 for transmission. When the main beam 1 moves, the power of the hydraulic motor 16 serves as the main power for the movement of the main beam 1, driving the gear 15 to drive the main beam 1 forward through the meshed rack 14. When the walking beam 7 moves, the power of the hydraulic motor 16 serves as the main power for the movement of the walking beam 7, driving the gear 15 to drive the walking beam 7 and itself to move forward through the meshed rack 14.

[0040] The working principle of the present invention is as follows: under the bridge pouring construction condition, the rear end of the main beam 1 is anchored on the bridge body through the rear anchor beam 1 2 and the rear anchor beam 2 4, at which time the hydraulic jack of the rear outrigger 3 is supported on the bridge body, the middle part of the main beam 1 is supported by the front support seat and the pad, and the front outrigger 12 at the front end of the main beam 1 is in a suspended state; after the bridge is poured and maintained, the front outrigger 12 is supported on the bridge body by a hydraulic jack, and enters the walking condition;

[0041] The anchoring of the walking beam 17 is cancelled, and the main beam 1 is lifted by the hydraulic jack to reserve a moving space for the walking beam 17 under the main beam 1; the pad above the front support seat 10 is taken out, and the rear hanging wheel 5 and the front hanging wheel in the front supporting hanging wheel integrated structure 9 are suspended on the outer extension of the bottom plate of the main beam 1 along with the lifting of the main beam 1; by operating the adjusting bolt 19 in the front supporting hanging wheel integrated structure 9, the adjusting base 20 is moved in the adjusting cavity 20 (equivalent to lowering the adjusting base 20 relative to the adjusting cavity 20), thereby driving the adjusting cavity 20, the wheel box base and the front end of the walking beam 17 to rise, thereby eliminating the gap between the gear 15 and the rack 14 caused by gravity, so that the gear 15 is meshed with the rack 14; the power of the hydraulic motor 16 drives the walking beam 17 to move forward to the specified position, and the hydraulic jack is recovered to make the walking beam 17 fall, and the walking beam 17 is bolted to the bridge body through the walking beam rear anchor seat 7 and the walking beam front anchor seat 11. After the hydraulic jack recovers the weight of the rear main beam 1, it is applied to the rear supporting wheel group 6 and the front supporting hanging wheel integrated structure 9, and the rear supporting wheel 6 abuts against the supporting wheel track 13; by operating the adjusting bolt 19 in the front supporting hanging wheel integrated structure 9, the adjusting base 20 is moved in the adjusting cavity 20 (equivalent to raising the adjusting base 20 relative to the adjusting cavity 20), thereby driving the adjusting cavity 20 and the wheel box base to descend, so that the front supporting wheel moves up and abuts against the supporting track 13, at this time, the gear 15 and the rack 14 are also in a meshing state, and the power of the hydraulic motor 16 drives the main beam 1 to move forward to the next casting position; after the main beam 1 is in place, the hydraulic jack of the rear support leg 3 is lowered, and the rear anchor beam 1 2 and the rear anchor beam 2 4 are used to anchor it to the bridge body, and a pad is set on the front support seat 10 to support the main beam 1, and the casting operation at this position can be carried out.

[0042] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0043] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An automatic walking mechanism of a suspended concrete bridge-building machine, characterized in that: The invention comprises two groups of walking units respectively arranged below a main beam (1); the walking units comprise a rear hanging wheel group (5), a rear supporting wheel group (6), a front supporting hanging wheel integrated structure (9) and a hydraulic motor transmission mechanism (8) which are arranged on a walking beam (17) in sequence from the back to the front; the lower end of the hydraulic motor transmission mechanism (8) is fixedly connected to the walking beam (17), and the upper end is meshingly connected to the lower end surface of the main beam (1) through a gear (15) and a rack (14), so as to drive the walking beam (17) and the main beam (1) to move; the lower end of the rear supporting wheel group (6) is meshed with the walking beam (17) and the upper end is meshed .... The rear suspension wheel group (5) is fixedly connected to the walking beam (17), and its upper end abuts against the bottom plate of the main beam (1) for supporting the main beam (1) to travel; the lower end of the rear suspension wheel group (5) is fixedly connected to the walking beam (17), and its upper end is suspended on the bottom plate of the main beam (1) for hanging the walking beam (17) on the main beam (1) for travel; the front supporting suspension wheel integrated structure (9) comprises a front supporting wheel and a front suspension wheel; the front supporting wheel is used to support the main beam (1) to travel together with the rear supporting wheel group (6); the front suspension wheel is used to hang the walking beam (17) on the main beam (1) for travel together with the rear suspension wheel group (5).

2. The automatic walking mechanism of the suspended grouting bridge-building machine according to claim 1 is characterized in that: The walking beam (17) is also provided with a walking beam rear anchor seat (7) and a walking beam front anchor seat (11); the walking beam rear anchor seat (7) and the walking beam front anchor seat (11) bolt the walking beam (17) to the bridge body via anchor bolts, thereby preventing the walking beam (17) from moving when the main beam (1) moves.

3. The automatic walking mechanism of the suspended grouting bridge-building machine according to claim 1 is characterized in that: A front support seat (10) is also fixedly provided on the walking beam (17) and is arranged in front of the front support wheel integrated structure (9); during bridge construction, a cushion block is arranged above the front support seat (10) to support the main beam (1); and an avoidance groove is also arranged at the center of the front support seat (10) to avoid the rack (14).

4. The automatic walking mechanism of the suspended concrete bridge-building machine according to claim 1 is characterized in that: Two support wheel tracks (13) are arranged on both sides of the lower end surface of the bottom plate of the main beam (1), and the upper end of the rear support wheel group (6) and the upper end of the front support wheel both abut against the support wheel tracks (13).

5. The automatic walking mechanism of the suspended concrete bridge-building machine according to claim 4 is characterized in that: The rear supporting wheel group (6) comprises a rear supporting wheel box and two groups of rear supporting wheels; the lower end of the rear supporting wheel box is bolted to the walking beam (17); the two groups of rear supporting wheels are rotatably arranged inside the rear supporting wheel box, and the upper ends are respectively abutted against two supporting wheel tracks (13).

6. The automatic walking mechanism of the suspended concrete bridge-building machine according to claim 4 is characterized in that: The rear wheel assembly (5) comprises a rear wheel box and two sets of rear wheels; the two sets of rear wheels are respectively arranged on the outer extension of the bottom plate of the main beam (1); the lower end of the rear wheel box is fixedly connected to the walking beam (17) and is rotatably connected to the two sets of rear wheels.

7. The automatic walking mechanism of the suspended grouting bridge-building machine according to claim 4 is characterized in that: The front supporting wheel integrated structure (9) comprises a wheel box base, two groups of front supporting wheels and two groups of telescopic mechanisms; the lower end surface of the wheel box base is fixedly connected to the walking beam (17); the upper ends of the two groups of front supporting wheels are respectively abutted against two supporting wheel tracks (13), and the middle parts are respectively rotatably connected to the wheel box base; the two groups of telescopic mechanisms are respectively fixedly arranged at the two ends of the wheel box base and clamped on both sides of the main beam (1).

8. The automatic walking mechanism of the suspended grouting bridge-building machine according to claim 7 is characterized in that: The telescopic mechanism comprises two front hanging wheels, a rotating shaft (18), an adjusting bolt (19), an adjusting base (20), an adjusting cavity (21) and a spring (22); the lower end of the adjusting cavity (21) is fixedly connected to the wheel box base; a base plate (23) is arranged in the middle of the adjusting cavity (21); the lower end of the adjusting base (20) is arranged above the base plate (23); the upper end of the spring (22) abuts against the lower wall of the adjusting base (20), and the lower end abuts against the base plate (23); the adjusting bolt (19) passes through the upper and lower walls of the base plate (23), the spring (22) and the adjusting base (20), and is fixed above the upper wall of the adjusting base (20) by a nut after adjustment.

9. The automatic walking mechanism of the suspended concrete bridge-building machine according to claim 1 is characterized in that: The hydraulic motor transmission mechanism (8) comprises a hydraulic motor fixing seat, a hydraulic motor (16) and a gear (15); The hydraulic motor (16) is fixed above the walking beam (17) via the hydraulic motor fixing seat; The output shaft of the hydraulic motor (16) is coaxially fixedly connected to the gear (15); a rack (14) is fixedly arranged at the center of the bottom plate of the main beam (1); and the gear (15) and the rack (14) are meshed for transmission.

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