Motor-driven cylindrical vibrator for subglacial lake drilling

Abstract

The present invention discloses a motor-driven columnar vibrator suitable for subglacial lake drilling, belonging to the field of polar subglacial lake drilling. The output shaft of the underwater motor rotates and drives a rotating component including a coupling, a cam drive shaft, and a cam to rotate synchronously with it. The cam is a circular cam with a repeated curved surface. During the cam's rotation, its upper surface contacts and pushes upward a linear vibrating component comprising a linear push rod, a parametric mass block, a cam follower mounting bracket, a spring base, a cantilever bearing, and a cam follower. During this process, the spring is compressed until the cam follower passes the highest point of the cam's upper surface curve. The spring is then released, causing the mating surface between the linear push rod and the frame top plate to impact and vibrate, and the vibration force is transmitted to the frame bottom plate through the frame side plates, completing a single impact. The present invention can greatly save the radial and axial dimensions of the vibrator structure, making the vibrator proposed by the present invention applicable to small-diameter drilling.

Description

Technical Field

[0001] The present invention belongs to the field of polar subglacial lake drilling, and more particularly, relates to a motor-driven columnar vibrator suitable for subglacial lake drilling. Background Art

[0002] Currently, drilling and sampling subglacial lakes is of great scientific significance for obtaining paleoclimate information, assessing stability, exploring life forms in extreme environments, and understanding the geological structure and processes at the base of the ice sheet. Most subglacial lakes lie beneath a kilometer-thick ice sheet, with the maximum overlying ice sheet thickness reaching 3,600 meters. To obtain sediment samples from the bottom of subglacial lakes, sampling equipment must drill through the surface to the ice layer of the subglacial lake before reaching the bottom of the lake for sediment sampling. Underwater sediment sampling equipment can be divided into pressure-type, gravity-impact type, hammer-type, and vibration-type power sources based on their operating principles. Vibration-type sampling has the highest penetration rate, the greatest penetration depth, and the least disturbance of sample bedding. However, limited Antarctic logistical support capabilities have limited the size of surface drilling equipment. Currently, borehole diameters used for subglacial lake exploration and sampling typically range from 100 to 300 mm. Bottom-hole equipment is typically powered by a surface generator coupled with a waterproof winch cable. Furthermore, due to the low temperatures of the ice layer and the resulting shrinkage of cavities, conventional underwater vibration power devices struggle to penetrate subglacial lake boreholes. With the continuous development of bottom-hole power technology, underwater motor drive technology has gradually matured. If an underwater motor is used as the prime mover for a vibration impact device for sampling subglacial lake sediments, coupled with a high-efficiency rotary-to-vibration converter suitable for the borehole size, efficient vibration devices can be used for subglacial lake sediment sampling. The main technical challenge limiting the application of vibration sampling technology in subglacial lake boreholes is how to convert the rotary power output of the underwater motor into efficient vibration impact energy while ensuring that the vibration device can be used in subglacial lake boreholes with limited diameters. Summary of the Invention

[0003] The purpose of the present invention is to address the technical problem that vibration sampling technology cannot be applied in subglacial lake drilling due to small hole diameter and limited bottom hole energy supply mode. A columnar vibrator that can use an underwater motor as a prime mover is proposed. The energy conversion efficiency and scalability of the vibration impact device in the subglacial lake drilling hole can be increased, and the energy loss, structural complexity, production and manufacturing cost of the bottom hole vibration impact device and the dependence on the surface energy supply device are reduced.

[0004] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a motor-driven columnar vibrator suitable for subglacial lake drilling, comprising a frame, a linear bearing, a thrust radial combination bearing, an underwater motor, a cam, a cam drive shaft, a cantilever bearing, a cam follower, a parametric mass block, a cam follower mounting frame, a linear push rod, a spring base, a spring and a spring top seat; the frame comprises a frame top plate, a frame side plate and a frame bottom plate, the frame top plate is opposite to the frame bottom plate, the frame side plate is connected between the frame top plate and the frame bottom plate, and the frame top plate, the frame side plate and the frame bottom plate form an accommodating space; the linear bearing is assembled on the frame top plate; the thrust radial combination bearing and the underwater motor are arranged in the accommodating space; the output shaft of the underwater motor is connected to the cam drive shaft through a coupling; the cam drive shaft and the thrust radial combination bearing are matched in a composite match of hole-shaft clearance fit and end face contact, so as to limit the movement of the cam drive shaft to only Radial; the cam and the cam transmission shaft are matched with a hole shaft and are detachably fastened together. The cam is a circumferential cam with a repeated curved surface, so that the cam follower that is in rolling contact with the cam curved surface rises or falls periodically with the rotating cam; the cantilever bearing and the cam follower are both matched with the hole shaft of the cam follower mounting bracket and are fixed by matching nuts to form an integrated structure; the outer peripheral surface of the cantilever bearing serves as a rolling contact surface that is in rolling contact with the side plate of the frame, so that when the cam rotates, the cam follower mounting bracket can only perform linear motion; the linear push rod has a T-shaped structure, the bottom is fixed to the cam follower mounting bracket by a threaded connection, the top is detachably fixed to the parametric mass block, and the linear push rod is matched with the linear bearing shaft hole; the spring base and the spring top seat are both matched with the hole shaft of the linear push rod, and the spring base and the spring top seat are respectively pressed on the frame top plate and the cam follower mounting bracket by springs.

[0005] Furthermore, the linear bearing is matched with the frame top plate hole axis and fixed by screws.

[0006] Furthermore, the thrust radial combined bearing and the underwater motor are respectively mounted on the frame side plate through the bearing mounting transverse plate and the underwater motor mounting plate, and the thrust radial combined bearing and the bearing mounting transverse plate are matched through the hole shaft.

[0007] Furthermore, the number of the parametric mass block is at least one.

[0008] Furthermore, the underwater motor is powered by a surface generator in combination with an armored cable winch or a bottom hole battery.

[0009] The working principle of the present invention is as follows:

[0010] After the motor-driven columnar vibrator suitable for subglacial lake drilling provided by the present invention is assembled, the output shaft of the underwater motor rotates and drives the rotating parts including the coupling, the cam transmission shaft and the cam to rotate synchronously with it. During the rotation of the cam, its upper surface contacts the cam follower and pushes up the linear vibration component including the linear push rod, the parametric mass block, the cam follower mounting frame, the spring base, the cantilever bearing and the cam follower. In this process, the spring is compressed until the cam follower passes the highest point of the curved surface on the cam. The spring is released and causes the mating surface between the linear push rod and the frame top plate to impact and vibrate, and transmit the vibration force to the frame bottom plate through the frame side plate to complete a single impact. The upper surface of the cam is a repeated curved surface, thereby forming a plurality of peaks and troughs on the upper surface of the cam. The output shaft of the underwater motor continues to rotate and repeats the above process to achieve high-frequency vibration. The vibration frequency of the entire vibrator can be increased by increasing the number of repeated curved surfaces on the upper part of the cam.

[0011] Through the above design scheme, the present invention can bring the following beneficial effects:

[0012] First, a circular cam with a repeated curved surface is used in combination with a cam follower to achieve periodic linear motion, and at the same time, spring energy storage is used to generate periodic linear vibration force, which can greatly save the radial and axial dimensions of the vibrator structure, so that the vibrator described in the present invention can be used for small diameter drilling.

[0013] Second, the vibrator of the present invention adopts an underwater motor at the bottom of the hole as the prime mover. The underwater motor adopts a surface generator with an armored cable winch or a battery at the bottom of the hole for power supply. The surface supporting equipment is simple and the application occasions are wider.

[0014] Third, the vibrator described in the present invention has a columnar structure. For applications with higher requirements for the excitation force, the excitation force can be increased by increasing the number of parametric mass blocks, or by using the principle of mechanical self-synchronization to connect multiple vibrators in series in the same diameter borehole, and arrange multiple vibrators in the axial direction to multiply the vibration force at the bottom of the hole.

[0015] Fourth, the present invention has a simple structure, is easy to disassemble, maintain and replace, has low technical complexity and low technical requirements for personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings herein are used to provide a further understanding of the present invention and constitute a part of the present application. The exemplary embodiments of the present invention and their descriptions are used to understand the present invention and do not constitute improper limitations of the present invention. In the accompanying drawings:

[0017] Figure 1 Isometric view of a motor-driven cylindrical vibrator suitable for drilling in subglacial lakes.

[0018] Figure 2Isometric bottom view of a motor-driven cylindrical vibrator suitable for drilling in subglacial lakes.

[0019] Figure 3 Front view of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0020] Figure 4 A half-section view of the main structure of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0021] Figure 5 A partial cross-sectional view of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0022] Figure 6 A partial cross-sectional view from the left of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0023] Figure 7 An isometric diagram of the rotating components of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0024] Figure 8 This is a front view of the rotating components of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0025] Figure 9 This is a left-side structural diagram of the rotating components of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0026] Figure 10 An isometric diagram of the linear vibrating component of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0027] Figure 11 This is a front view of the linear vibration component of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0028] Figure 12 This is a left-side structural diagram of the linear vibration component of a motor-driven cylindrical vibrator suitable for drilling holes in subglacial lakes.

[0029] Figure 13 Schematic diagram of a single vibration process of a motor-driven cylindrical vibrator suitable for drilling in subglacial lakes.

[0030] The marks in the figure are as follows: 1-first screw; 2-parametric mass block; 3-second screw; 4-frame top plate; 5-frame side plate; 6-bearing mounting cross plate; 7-third screw; 8-underwater motor mounting plate; 9-fourth screw; 10-frame bottom plate; 11-spring top seat; 12-spring; 13-spring base; 14-cam follower mounting bracket; 15-cantilever bearing; 16-cam follower; 17-cam; 18-thrust radial combination bearing; 19-coupling; 20-fifth screw; 21-underwater motor; 22-sixth screw; 23-cam drive shaft; 24-linear push rod; 25-seventh screw; 26-linear bearing; 27-eighth screw. DETAILED DESCRIPTION

[0031] In order to make the objects, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the present invention are clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the present invention is not limited to the following embodiments, and the specific implementation method can be determined according to the technical solution of the present invention and actual conditions. In order to avoid confusing the essence of the present invention, well-known methods, processes, flows, components and circuits are not described in detail. It should be understood that the terms "first", "second", "third", "fourth", "fifth", "sixth", "seventh" and "eighth" are only used for descriptive purposes, and the features defined as "first", "second", "third", "fourth", "fifth", "sixth", "seventh" and "eighth" do not represent any order, quantity or importance, but are only used to distinguish different components.

[0032] like Figures 1 to 12As shown, the motor-driven columnar vibrator suitable for subglacial lake drilling proposed in the present invention includes a first screw 1, a parametric mass block 2, a second screw 3, a frame top plate 4, a frame side plate 5, a bearing mounting cross plate 6, a third screw 7, an underwater motor mounting plate 8, a fourth screw 9, a frame bottom plate 10, a spring top seat 11, a spring 12, a spring base 13, a cam follower mounting bracket 14, a cantilever bearing 15, a cam follower 16, a cam 17, a thrust radial combination bearing 18, a coupling 19, a fifth screw 20, an underwater motor 21, a sixth screw 22, a cam drive shaft 23, a linear push rod 24, a seventh screw 25, a linear bearing 26 and an eighth screw 27. The frame top plate 4 is opposite to the frame bottom plate 10, and the frame side plate 5 is connected between the frame top plate 4 and the frame bottom plate 10. The frame top plate 4, the frame side plate 5 and the frame bottom plate 10 form an accommodating space; the frame top plate 4 is fixed to the frame side plate 5 by the second screw 3, and the frame bottom plate 10 is also fixed to the frame side plate 5 by the sixth screw 22; the bearing mounting cross plate 6 is fixed to the frame side plate 5 by the third screw 7, and the underwater motor mounting plate 8 is fixed to the frame side plate 5 by the fourth screw 9. The linear bearing 26 is matched with the hole axis of the frame top plate 4 and is fixed to the frame top plate 4 by the seventh screw 25. The thrust radial combination bearing 18 is matched with the bearing mounting cross plate 6 through the hole axis clearance. The underwater motor 21 is connected to the underwater motor mounting plate 8 by a threaded matching manner through the fifth screw 20. The frame top plate 4, the frame side plate 5, the bearing mounting cross plate 6, the underwater motor mounting plate 8, the frame bottom plate 10, the thrust radial combination bearing 18, the underwater motor 21 and the linear bearing 26 can be regarded as an integrated assembly. The thrust radial combined bearing 18 is an industrial product and is a commercially available product that can withstand radial and axial loads at the same time.

[0033] like Figure 7 、 Figure 8 and Figure 9 As shown, the cam 17, the cam drive shaft 23 and the coupling 19 form an integrally assembled rotating component. The cam 17 and the cam drive shaft 23 are hole-axis matched and fixed by the eighth screw 27. One end of the coupling 19 is connected to the output shaft of the underwater motor 21, and the other end is connected to the cam drive shaft 23 and locked. The rotation of the output shaft of the underwater motor 21 will drive the coupling 19, the cam drive shaft 23 and the cam 17 to rotate in turn, outputting speed and torque. At the same time, the cam drive shaft 23 and the thrust radial combination bearing 18 form a hole-axis and end face composite match, and the thrust radial combination bearing 18 simultaneously bears the radial and axial loads in the rotational motion of the cam drive shaft 23.

[0034] like Figure 4 、 Figure 5 、 Figure 6 、 Figure 10 、 Figure 11 and Figure 12As shown, the parametric mass block 2, the linear push rod 24, the spring base 13, the cam follower mounting bracket 14, the cantilever bearing 15 and the cam follower 16 together constitute an integrally assembled linear vibration component and can perform single-degree-of-freedom linear relative motion with the linear bearing 26. At least one parametric mass block 2 is fixed to the top of the linear push rod 24 by a first screw 1. The parametric mass block 2 is an additional structure for increasing the exciting force during the vibration process, that is, under the same vibration speed conditions, the more parametric mass blocks 2 there are, the greater the exciting force. The number of parametric mass blocks 2 can be increased or decreased according to the vibration force requirements. The linear push rod 24 has a T-shaped structure. The bottom of the linear push rod 24 is fixed to the cam follower mounting bracket 14 by a threaded connection. The spring base 13 is nested on the linear push rod 24 and can be pressed against the upper plane of the cam follower mounting bracket 14 by a spring 12. The cantilever bearing 15 and the cam follower 16 are both industrial products and are commercially available products. The cantilever bearing 15 and the cam follower 16 are both The cam follower mounting frame 14 is matched with the hole axis and is fixed by a matching nut. When the cam 17 rotates and contacts the cam follower 16, it not only generates axial thrust but also generates additional torque. In order to ensure that the various components connected to the cam follower mounting frame 14 do not rotate due to this torque, a cantilever bearing 15 is provided on the cam follower mounting frame 14. Since the cantilever bearing 15 is limited by the inner surface of the frame side plate 5, the cantilever bearing 15 is used to keep the cam follower mounting frame 14, the cam follower 16 and the linear push rod 24 able to only perform linear motion. The function of the cam follower 16 is to form contact with the cam 17, and when the cam 17 rotates, the cam follower 16 can drive the cam follower mounting frame 14, the cantilever bearing 15, the linear push rod 24 and the parametric mass block 2 to perform linear motion. The linear push rod 24 and the linear bearing 26 are matched with the hole axis clearance. The spring top seat 11 is nested on the linear push rod 24 and can be pressed against the lower plane of the frame top plate 4 by the spring 12.

[0035] The cam 17 is a circular cam with a repeated curved surface. Specifically, the structure of the cam 17 is to form at least two arc-shaped curved grooves with the same structure along the circumferential direction on the upper surface of the cylinder. When the cam 17 rotates, since the cam follower 16 can only move axially up and down (reset by the spring 12), the cam follower 16 moves up and down linearly once every time the cam 17 rotates through a period of angle, forming a single impact, which in turn drives the cam follower mounting frame 14, the cantilever bearing 15, the linear push rod 24 and the parametric mass block 2 to achieve a single impact on the entire vibrator. The cam 17 rotates continuously, and the cam follower 16 and the integrated structure continuously move back and forth linearly, resulting in a repeated impact effect, that is, vibration; please refer to the movement process. Figure 13 .

[0036] Figure 13 This is a schematic diagram of a single vibration process of the motor-driven cylindrical vibrator suitable for subglacial lake drilling according to the present invention, combined with Figures 3 to 12 After the motor-driven columnar vibrator suitable for subglacial lake drilling according to the present invention is assembled, the underwater motor 21 is used to drive the output shaft of the underwater motor 21 to rotate, and in turn drives the rotating components composed of the coupling 19, the cam drive shaft 23 and the cam 17 to finally achieve synchronous rotation of the cam 17 and the output shaft of the underwater motor 21. During the rotation of the cam 17, the cantilever bearing 15 installed on the cam follower mounting frame 14 is in line contact with the frame side plate 5. Combined with the hole-axis clearance between the linear push rod 24 and the linear bearing 26 installed as an integral part of the cam follower mounting frame 14, the linear vibration component including the cam follower mounting frame 14 can only perform axial linear motion. The upper repeating surface of the cam 17 and the cam follower 16 roll relative to each other. As the cam follower 16 moves from the lowest point to the highest point along the upper repeating surface of the cam 17, the cam follower 16 drives the entire linear vibration component upward. The spring 12 is compressed to store elastic potential energy. When the cam follower 16 moves to the upper repeating surface of the cam 17, the cam follower 16 moves upward. At the end of the highest point curved surface, the spring 12 releases elastic potential energy, and the cam follower 16 and the entire linear vibration component move downward rapidly under the elastic force of the spring 12. The linear push rod 24 in the linear vibration component impacts the frame top plate 4, and the frame top plate 4 transmits the impact force to the frame bottom plate 10 through the frame side plate 5. The bottom surface of the frame bottom plate 10 is the power output end of the entire columnar vibrator. At this point, the single vibration process of the motor-driven columnar vibrator suitable for subglacial lake drilling is completed. If the output shaft of the underwater motor 21 continues to rotate, the above-mentioned impact process is repeated, and finally the periodic vibration of the entire columnar vibrator is realized. The vibration frequency of the entire columnar vibrator can be increased by increasing the number of repeated curved surfaces on the upper part of the cam 17.

Claims

1. A motor-driven columnar vibrator suitable for drilling holes in subglacial lakes, comprising a frame, wherein the frame comprises a frame top plate (4), a frame side plate (5) and a frame bottom plate (10), wherein the frame top plate (4) is opposite to the frame bottom plate (10), the frame side plate (5) is connected between the frame top plate (4) and the frame bottom plate (10), and the frame top plate (4), the frame side plate (5) and the frame bottom plate (10) enclose an accommodating space; characterized in that: Also includes: A linear bearing (26), a thrust radial combined bearing (18), an underwater motor (21), a cam (17), a cam transmission shaft (23), a cantilever bearing (15), a cam follower (16), a parametric mass block (2), a cam follower mounting frame (14), a linear push rod (24), a spring base (13), a spring (12) and a spring top seat (11); the linear bearing (26) is assembled on the frame top plate (4); the thrust radial combined bearing (18) and the underwater motor (21) are arranged on the frame top plate (4); The cam drive shaft (23) is connected to the cam drive shaft (23) through a coupling (19); the cam drive shaft (23) and the thrust radial combined bearing (18) are matched in a composite fit of hole-shaft clearance fit and end-face contact, so as to limit the movement of the cam drive shaft (23) only to the radial direction; the cam (17) and the cam drive shaft (23) are matched in a hole-shaft manner and are detachably fastened together, and the cam (17) is a circumferential cam with a repeated curved surface, so as to make the cam (17) curved. The cam follower (16) with rolling contact on the surface rises or falls periodically with the rotating cam (17); the cantilever bearing (15) and the cam follower (16) are both hole-shaft matched with the cam follower mounting frame (14) and are fixed by matching nuts to form an integrated structure; the outer peripheral surface of the cantilever bearing (15) serves as a rolling contact surface for rolling contact with the frame side plate (5), so that when the cam (17) rotates, the cam follower mounting frame (14) can only perform linear motion; the linear push The rod (24) is in a T-shaped structure, the bottom is fixed to the cam follower mounting frame (14) by a threaded connection, the top is detachably fixed to the parametric mass block (2), and the linear push rod (24) is matched with the axis hole of the linear bearing (26); the spring base (13) and the spring top seat (11) are both matched with the linear push rod (24) in a hole-axis clearance, and the spring base (13) and the spring top seat (11) are respectively pressed on the frame top plate (4) and the cam follower mounting frame (14) by the spring (12).

2. The motor-driven columnar vibrator suitable for subglacial lake drilling according to claim 1, characterized in that: The linear bearing (26) is matched with the hole axis of the frame top plate (4) and fixed by screws.

3. The motor-driven columnar vibrator suitable for subglacial lake drilling according to claim 1, characterized in that: The thrust radial combined bearing (18) and the underwater motor (21) are respectively mounted on the frame side plate (5) via a bearing mounting transverse plate (6) and an underwater motor mounting plate (8), and the thrust radial combined bearing (18) and the bearing mounting transverse plate (6) are matched via a hole shaft.

4. The motor-driven columnar vibrator suitable for subglacial lake drilling according to claim 1, characterized in that: The number of the parametric mass block (2) is at least one.

5. The motor-driven columnar vibrator suitable for subglacial lake drilling according to claim 1, characterized in that: The underwater motor (21) is powered by a surface generator in combination with an armored cable winch or a bottom hole battery.

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