Drop hammer seismic source device and drop hammer seismic source vehicle for urban active fault exploration

Abstract

The invention discloses a drop hammer vibration source device and a drop hammer vibration source vehicle for urban active fault exploration. The drop hammer vibration source device comprises a drop hammer, a base plate and a lifting mechanism for lifting the drop hammer, an electromagnet is arranged in the center of the interior of the base plate, the electromagnet is powered on when the drop hammer falls, and the electromagnet is used for achieving suction of the drop hammer while the drop hammer impacts the base plate, preventing secondary impact of the drop hammer and effectively controlling the rebound problem of the drop hammer. The lifting mechanism is connected with the drop hammer in an electromagnetic chuck mode to form a double-magnetic type drop hammer vibration source system, so that the drop hammer can be lifted at any height, and the excitation energy can be effectively adjusted. And through the arrangement of the graphite metal sliding block and the replaceable sliding rail, the downward sliding resistance of the drop hammer is greatly reduced, and maintenance is convenient. And the drop hammer and the base plate are integrally formed by adopting a casting process, so that the drop hammer is durable, reliable and long in service life. And the vehicle body is moved by adopting a universal forklift, and the stability and balance of the forklift are used for reference, so that the device is convenient to move, good in stability and suitable for urban active fault exploration.

Description

Technical Field

[0001] The present invention relates to the technical field of urban active fault detection, and in particular to a drop hammer source device and a drop hammer source vehicle for urban active fault exploration. Background Art

[0002] Seismic exploration is one of the most sophisticated and accurate means of urban active fault detection. It uses the principle of seismic wave reflection at different soil / lithology interfaces to track the spatial distribution of underground stratum interfaces. Field data collection for urban seismic exploration includes the excitation and reception of artificial seismic waves. Whether seismic waves with high energy and high stability can be excited determines the accuracy of active fault exploration.

[0003] At present, there are many ways to generate artificial seismic waves in seismic exploration, such as explosives, source guns, electric sparks, controllable vibrators, and drop hammer sources. Among them, the explosive source is a source that uses detonators or small-volume explosions in shallow holes to excite seismic waves (Sharp, 1942). Since the seismic waves excited by explosives have a wide spectrum and rich high-frequency components, the energy can be controlled by changing the amount of charge, and the exploration depth can reach several kilometers or even tens of kilometers. It is an effective source commonly used in high-resolution seismic exploration; the source gun shoots bullets into water-filled or wet shallow holes and uses the impact or explosion of the bullets to excite seismic waves. Since the source gun shoots the bullet vertically downward into the hole, it plays a directional role, which is conducive to the downward propagation of the excitation energy. However, both explosives and source guns have the problem of damaging the road surface, and are not suitable for urban active fault detection.

[0004] The controllable vibrator mainly transmits a set of continuous vibration scanning signals to the underground in a reaction manner through a vibrating plate that is tightly coupled to the ground. However, its structure is relatively complex and has a high cost. The drop hammer source is excited by lifting a heavy object to a certain height and then dropping it to impact the ground. It has a relatively economical cost. For example, under the same excitation energy conditions, the cost of the drop hammer source is generally no more than one-fifth of that of the controllable vibrator. In addition, the drop hammer source also has a series of advantages such as strong energy, good repeatability, non-destructiveness to the road surface, and easy mobility, which makes it suitable for use in urban environments.

[0005] However, the existing drop hammer seismic source devices still have obvious disadvantages: (1) Due to the large mass of the drop hammer, it is still inconvenient to lift and move it, and the safety is poor; (2) The drop hammer and the pad themselves have high strength requirements. Most of the existing drop hammers and pads are combined structures, which are easily damaged and have a short service life due to the huge instantaneous impact generated by the drop hammer; (3) The stability of the drop hammer is generally poor during the falling process, and when it contacts the hard ground or the pad, it is easy to rebound, causing secondary excitation and affecting the survey results.

[0006] It can be seen that the above existing drop hammer source device obviously still has inconveniences and defects, and is in urgent need of further improvement. How to create a new drop hammer source device and drop hammer source vehicle for urban active fault exploration, so that it can solve the problem of the source device being easily damaged under high energy impact conditions, the rebound problem caused by the drop hammer, and improve the drop hammer's falling stability and mobility, has become a goal that the industry urgently needs to improve. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a drop hammer seismic source device for urban active fault exploration, so that it can solve the problem that the seismic source device is easily damaged under high-energy impact conditions, as well as the rebound problem caused by the falling of the drop hammer, and improve the falling stability and mobility of the drop hammer, thereby overcoming the shortcomings of the existing drop hammer seismic source devices.

[0008] In order to solve the above technical problems, the present invention provides a drop hammer seismic source device for urban active fault exploration, including a drop hammer and a pad for being arranged directly below the drop hammer, and a lifting mechanism for lifting the drop hammer. An electromagnet is provided at the inner center of the pad. The electromagnet is energized when the drop hammer falls, so as to attract the drop hammer while the drop hammer hits the pad, thereby preventing a secondary impact of the drop hammer.

[0009] Further improvement, the lifting mechanism includes a door frame, an electromagnetic suction cup, a suction cup fixing plate and a lifting cylinder, the door frame includes two oppositely arranged door columns and a plurality of U-shaped connecting rods connecting the two door columns, the drop hammer is located between the two door columns, the electromagnetic suction cup is fixed to the bottom of the suction cup fixing plate, the suction cup fixing plate is located between the two door columns and fixedly connected to the protruding end of the lifting cylinder, when the electromagnetic suction cup is energized, the top of the drop hammer is attracted by the electromagnetic suction cup, and under the action of the lifting cylinder, it is lifted to a predetermined height along with the suction cup fixing plate, and when the electromagnetic suction cup loses power, the drop hammer falls vertically along the door column.

[0010] According to further improvements, the lifting mechanism also includes a pulley and a lifting chain, the central axis of the pulley is fixedly connected to the protruding end of the lifting cylinder, one end of the lifting chain is connected to the suction cup fixing plate, and the other end of the lifting chain is connected to the U-shaped connecting rod at the bottom of the door frame after passing around the pulley. The pulley is lifted up and down by the telescopic action of the lifting cylinder, and the lifting chain drives the suction cup fixing plate to be lifted and lowered as the pulley is lifted and lowered.

[0011] As a further improvement, the lifting cylinders include two, which are respectively arranged beside the door pillars, and connecting frames are arranged at the protruding ends of the two lifting cylinders, and the pulleys are respectively arranged at both ends of the connecting frames, and the pulleys are respectively arranged corresponding to the lifting chains.

[0012] As a further improvement, detachable slide rails are embedded on opposite sides of the two door posts, and slide grooves matching the slide rails are respectively provided on both sides of the drop hammer.

[0013] As a further improvement, the slide rail adopts a semi-cylindrical structure, the slide groove adopts an inwardly concave arc-shaped groove body, and a graphite metal slider is embedded on the arc-shaped inner wall of the slide groove, and the graphite metal slider is in contact with the slide rail.

[0014] As a further improvement, the drop hammer is integrally formed by a casting process, and the inner walls of the slide grooves on both sides thereof are provided with embedding grooves for embedding graphite metal sliding blocks.

[0015] As a further improvement, the pad is integrally formed by a casting process, a groove for mounting the electromagnet is provided at the bottom of the pad, connecting holes are provided on both sides of the pad, and the connecting holes at both ends of the pad are movably connected to the lower parts of the two door pillars by chain ropes.

[0016] As a further improvement, a lifting cylinder is provided on the outer side of the lower part of the two door posts, and the lifting cylinder drives the chain rope to realize the lifting action, thereby driving the pad to descend to the ground when in use or to leave the ground when moving.

[0017] As another improvement of the present invention, the present invention also provides a drop hammer source vehicle for urban active fault exploration. The drop hammer source vehicle comprises a mobile vehicle body and the above-mentioned drop hammer source device, the mobile vehicle body adopts a mobile vehicle body of a forklift structure, and the drop hammer source device is fixed to the front part of the mobile vehicle body of the forklift structure.

[0018] After adopting such a design, the present invention has at least the following advantages:

[0019] 1. The drop hammer source device of the present invention embeds an electromagnet inside the pad so that when the drop hammer falls to the pad, it can be attracted to the pad, effectively preventing the rebound of the drop hammer, avoiding secondary excitation caused by the rebound of the drop hammer, and effectively solving the rebound problem of the drop hammer.

[0020] 2. The lifting mechanism is connected to the drop hammer by means of an electromagnetic suction cup to form a double magnetic drop hammer source system, which can not only meet the lifting of the drop hammer to any height, effectively adjust the excitation energy of the drop hammer, but also effectively solve the problem of drop hammer rebound.

[0021] 3. The slide rail is arranged to be replaceable, which is convenient for replacement, maintenance and extended service life; and a graphite metal slider is used between the slide rail and the drop weight to greatly reduce the sliding resistance and facilitate the control of the impact force of the drop weight.

[0022] 4. The drop weight and the pad are integrally formed by a casting process, making them durable and reliable as impact components, avoiding the defects of the drop weight and the pad formed by the existing combination, such as the connection part breaking under continuous impact and the short service life.

[0023] 5. Chain ropes are used to realize the movable connection between the pad and the door post, and the lifting cylinder is set up, so that the pad can be easily lifted to the lower edge of the door post as the source vehicle moves forward, and the pad can be lowered to the ground before the source vehicle is excited, which is flexible, convenient and easy to operate.

[0024] 6. The drop hammer seismic source vehicle of the present invention adopts the mobile body part of the existing general-purpose forklift and draws on the stability and balance of the forklift itself to facilitate the transportation of the drop hammer seismic source device and the excitation of seismic waves when the drop hammer falls to impact the ground, thereby improving the drop stability and mobility of the drop hammer, and is suitable for urban active fault exploration. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0026] Figure 1 It is a schematic diagram of the overall structure of the drop hammer source device of this embodiment.

[0027] Figure 2 It is a schematic diagram of the structure of the drop hammer in the drop hammer source device of this embodiment.

[0028] Figure 3 It is a schematic diagram of the structure of the graphite metal slider in the drop hammer source device of this embodiment. DETAILED DESCRIPTION

[0029] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0030] Refer to the attached Figure 1 As shown, the drop hammer source vehicle of this embodiment is used for urban active fault survey, and comprises a mobile body 1 and a drop hammer source device 2 located at the front thereof. The mobile body 1 adopts a mobile body of a forklift structure, and the drop hammer source device is fixed at the front of the mobile body of the forklift structure.

[0031] In this embodiment, the mobile body 1 adopts the mobile body part of the existing general forklift structure, which can refer to the stability and balance of the forklift itself, meet the lifting balance of the drop hammer in the drop hammer source device, and meet the transportation of the overall drop hammer source device with a large weight drop hammer (more than 1 t), thereby improving the convenience of mobility. Of course, the mobile body can also adopt other body structures with mobile functions.

[0032] Please refer to the attached Figure 1 As shown, the drop hammer source device 2 includes a drop hammer 21 and a pad 22 disposed directly below the drop hammer 21, and a lifting mechanism for lifting the drop hammer 21. When the drop hammer source device 2 is moved by the mobile vehicle 1 to a place to be surveyed, the lifting mechanism lifts the drop hammer 21 to a predetermined height, the pad 22 is located on the ground, and the lifting mechanism releases the drop hammer 21 to fall, thereby impacting the pad 22, thereby generating an impact seismic wave on the ground. The height of the drop hammer 21 can be set according to user needs to adjust the magnitude of the excitation energy.

[0033] The improvement of this embodiment is that an electromagnet 23 is provided at the inner center of the pad 22. The electromagnet 23 is energized when the drop hammer 21 falls, and is used to attract the drop hammer 21 while the drop hammer 21 impacts the pad 22, thereby preventing the drop hammer 21 from having a secondary impact and effectively controlling the drop hammer rebound problem.

[0034] In this embodiment, the pad 22 is integrally formed by a casting process, a groove 221 for mounting the electromagnet 23 is provided at the bottom of the pad 22 , and connecting through holes 222 are provided at both sides of the pad 22 .

[0035] The lifting mechanism in this embodiment includes a door frame 24, an electromagnetic suction cup 25, a suction cup fixing plate 26, a lifting cylinder 27, a lifting chain 28 and a pulley 29. The door frame 24 adopts a frame structure formed by two oppositely arranged door columns 241 and a plurality of U-shaped connecting rods 242 connecting the two door columns 241, and is used to be fixed on the front part of the mobile vehicle body 1 to replace the fork part of the original forklift.

[0036] The drop hammer 21 is located between the two door columns 241, and the electromagnetic suction cup 25 is fixed to the bottom of the suction cup fixing plate 26. The suction cup fixing plate 26 is also located between the two door columns 241 and connected to the extended end of the lifting cylinder 27. When the electromagnetic suction cup 25 is powered on, the top of the drop hammer 21 can be sucked by the electromagnetic suction cup 25, that is, it can be lifted to a predetermined height along with the suction cup fixing plate 26. When the electromagnetic suction cup 25 loses power, the drop hammer 21 is released, so that the drop hammer 21 falls vertically along the door column 241.

[0037] Specifically, the lifting oil cylinder 27 includes two, which are respectively arranged beside the door column 241. The protruding ends of the two lifting oil cylinders 27 are provided with a connecting frame 30, and the two ends of the connecting frame 30 are respectively provided with a pulley 29, and the pulley 29 is respectively provided with a lifting chain 28. One end of the lifting chain 28 is connected to the suction cup fixing plate 26, and the other end of the lifting chain 28 is connected to the U-shaped connecting rod 242 at the lower part of the door frame after bypassing the pulley 29. Then, the pulley 29 is lifted up and down with the telescopic effect of the lifting oil cylinder 27. Since the lower end of the lifting chain 28 is fixed by the U-shaped connecting rod 242, the upper end of the lifting chain 28 relies on the rolling of the pulley 29, and the lifting and lowering drive of the suction cup fixing plate 26 is realized with the lifting and lowering of the pulley 29.

[0038] In addition, in this embodiment, the two door posts 241 are both embedded with slide rails 31 on opposite sides, and the two sides of the drop hammer 21 are respectively provided with slide grooves 211 matching the slide rails 31. The cooperation between the slide rails 31 and the slide grooves 211 can ensure that the drop hammer 21 falls vertically, avoid deviation accidents, and improve safety.

[0039] Specifically, the slide rail 31 adopts a hollow semi-cylindrical structure, the flat side of which is inserted into the concave groove of the door post 241, and the arc-shaped side of which is opposite to the slide groove 211. The slide groove 211 adopts an inwardly concave arc-shaped groove body matching the arc-shaped side of the slide rail 31. Preferably, the slide rail 31 can be freely plugged and unplugged along the concave groove to form a detachable slide rail, which is convenient for replacement of the slide rail and is conducive to maintenance.

[0040] In order to reduce the friction resistance when the drop hammer falls, the arc-shaped inner wall of the slide groove 211 is embedded with a graphite metal slider 32. The graphite metal slider 32 contacts the slide rail 31, which can greatly reduce the resistance of the drop hammer to slide down. The drop hammer 21 in this embodiment is integrally formed by a casting process, which greatly improves the impact resistance of the drop hammer. The inner wall of the slide groove 211 on both sides of the drop hammer 21 is provided with an embedding groove body 212 for embedding the graphite metal slider 32, as shown in the attached Figure 2 and 3 shown.

[0041] Please refer to the attached Figure 1 As shown, the two ends of the pad 22 are movably connected to the bottom ends of the two door pillars 241 through chain ropes 33. Specifically, in this embodiment, a lifting cylinder 34 is provided on the outer side of the bottom ends of the two door pillars 241. The lifting cylinder 34 can drive the chain rope 33 to achieve lifting action, thereby driving the pad 22 to descend to the ground in the survey state, and to be detached from the ground when the source vehicle moves for easy movement.

[0042] The complete source excitation process of the drop hammer source vehicle of the present invention is as follows:

[0043] (1) The moving vehicle body 1 moves the drop hammer source device 2 to the desired survey location, the extended end of the lifting cylinder 34 is retracted, and the pad 22 is lowered to the ground;

[0044] (2) The suction cup fixing plate 26 moves downward under the action of the lifting cylinder 27. When it contacts the drop hammer 21, the electromagnetic suction cup 25 is energized to attract the top of the drop hammer 21 and lift the drop hammer 21 under the drive of the lifting cylinder 27.

[0045] (3) After the drop hammer 21 reaches a predetermined height, the electromagnetic suction cup 25 loses power, and at the same time, the electromagnet 23 in the pad 22 is energized, and the drop hammer 21 falls and impacts the pad 22 and is attracted to the pad 22, generating high-energy seismic waves;

[0046] (4) The electromagnet 23 loses power, and the above steps (2) and (3) are repeated to complete the next excitation.

[0047] The drop hammer seismic source vehicle of the present invention is perfectly compatible with existing general-purpose forklifts. By drawing on the stability and balance of the forklift itself, it can not only improve the mobility of the drop hammer seismic source device, but also improve the stability of the drop hammer falling and impacting the ground, which is suitable for urban active fault exploration.

[0048] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Those skilled in the art may make some simple modifications, equivalent changes or modifications using the technical contents disclosed above, which all fall within the protection scope of the present invention.

Claims

1. A drop hammer source device for urban active fault exploration, characterized in that: It includes a drop hammer and a pad arranged directly below the drop hammer, and a lifting mechanism for lifting the drop hammer. An electromagnet is provided at the inner center of the pad. The electromagnet is energized when the drop hammer falls, so as to attract the drop hammer while the drop hammer hits the pad, thereby preventing the drop hammer from having a secondary impact.

2. The drop weight source device according to claim 1, characterized in that: The lifting mechanism includes a door frame, an electromagnetic suction cup, a suction cup fixing plate and a lifting cylinder. The door frame includes two oppositely arranged door columns and a plurality of U-shaped connecting rods connecting the two door columns. The drop hammer is located between the two door columns. The electromagnetic suction cup is fixed to the bottom of the suction cup fixing plate. The suction cup fixing plate is located between the two door columns and fixedly connected to the protruding end of the lifting cylinder. When the electromagnetic suction cup is energized, the top of the drop hammer is attracted by the electromagnetic suction cup and, under the action of the lifting cylinder, is lifted to a predetermined height along with the suction cup fixing plate. When the electromagnetic suction cup loses power, the drop hammer falls vertically along the door column.

3. The drop weight source device according to claim 2, characterized in that: The lifting mechanism also includes a pulley and a lifting chain. The central axis of the pulley is fixedly connected to the protruding end of the lifting cylinder, one end of the lifting chain is connected to the suction cup fixing plate, and the other end of the lifting chain is connected to the U-shaped connecting rod at the bottom of the door frame after passing around the pulley. The pulley is lifted up and down with the extension and contraction of the lifting cylinder, and the lifting chain drives the suction cup fixing plate to be lifted and lowered as the pulley is lifted and lowered.

4. The drop weight source device according to claim 3, characterized in that: The lifting cylinders include two, which are respectively arranged beside the door pillars. Connecting frames are arranged at the protruding ends of the two lifting cylinders. The pulleys are respectively arranged at both ends of the connecting frames. The pulleys are respectively arranged corresponding to the lifting chains.

5. The drop weight source device according to claim 2, characterized in that: Removable slide rails are embedded on opposite sides of the two door posts, and slide grooves matching the slide rails are respectively provided on both sides of the drop hammer.

6. The drop weight source device according to claim 5, characterized in that: The slide rail adopts a semi-cylindrical structure, the slide groove adopts an inwardly concave arc-shaped groove body, and a graphite metal slider is embedded on the arc-shaped inner wall of the slide groove, and the graphite metal slider is in contact with the slide rail.

7. The drop weight source device according to claim 5, characterized in that: The drop hammer is integrally formed by a casting process, and the inner walls of the slide grooves on both sides thereof are provided with embedding groove bodies for embedding graphite metal sliding blocks.

8. The drop weight source device according to claim 2, characterized in that: The pad is integrally formed by a casting process, a groove for installing the electromagnet is provided at the bottom of the pad, connecting through holes are provided on both sides of the pad, and the connecting through holes at both ends of the pad are movably connected to the lower parts of the two door pillars through chain ropes.

9. The drop weight source device according to claim 8, characterized in that: A lifting cylinder is also provided on the outer side of the lower part of the two door posts, and the lifting cylinder drives the chain rope to realize the lifting action, thereby driving the pad to descend to the ground when in use or to leave the ground when moving.

10. A drop hammer source vehicle for urban active fault survey, characterized in that: It comprises a mobile body and a drop hammer source device as claimed in any one of claims 1 to 9, wherein the mobile body is a mobile body of a forklift structure, and the drop hammer source device is fixed to the front part of the mobile body of the forklift structure.

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