Oscillating screw drill with constant pulsing force

Abstract

The application relates to an oscillating screw drill with constant pulse force, and belongs to the technical field of screw drills for oil exploitation. The oscillating screw drill comprises a drill body, a pulse assembly and a shaft. The drill body comprises a shell and a shaft, the shell is a hollow tubular structure, the shaft is located in the shell and rotates eccentrically around the axis of the shell; the pulse assembly comprises a static valve fixed in the shell, a dynamic valve rotating in the shell, and a transmission rod connected with the shaft to drive the dynamic valve to rotate coaxially in the shell and keep the axial distance between the dynamic valve and the static valve constant; the static valve is provided with a static valve flow channel, the dynamic valve is provided with a dynamic valve flow channel, and the dynamic valve rotates relative to the static valve to periodically change the flow area between the static valve flow channel and the dynamic valve flow channel. The axial pulse thrust generated by the pulse assembly of the application is completely transmitted to the shell, the load of the shaft and other rod parts of the screw drill is improved, the service life of the shaft and the bearing system of the oscillating screw drill is prolonged, and the efficiency of the whole oscillating screw drill is improved.

Description

Technical Field

[0001] This application relates to the field of screw drilling tools for oil exploration, and particularly to an oscillating screw drilling tool with constant pulse force. Background Technology

[0002] A screw drill is a type of positive displacement downhole power drill that uses drilling fluid as its power source, converting liquid pressure energy into mechanical energy. When the mud pumped out by the mud pump flows through the bypass valve into the motor, a certain pressure difference is formed between the motor's inlet and outlet, driving the rotor to rotate around the stator's axis. The rotational speed and torque are then transmitted to the drill bit through the universal joint and drive shaft, thereby realizing the drilling operation.

[0003] In the field of oil extraction, during directional drilling operations in highly deviated wells, extended reach wells, horizontal wells, and complex wellbores, the frictional resistance of the drill string against the wellbore wall makes it impossible to apply accurate pressure on the drill bit, severely impacting drilling efficiency. Therefore, reducing drill string frictional resistance and effectively feeding the drill string to accurately apply pressure on the drill bit is a crucial issue in solving complex well drilling technology.

[0004] Oscillating screw drills are effective tools for reducing frictional resistance and efficiently transmitting drilling pressure. These tools utilize periodic axial vibrations generated by pulsed pressure to effectively reduce frictional resistance between the drill string and the wellbore during drilling, thereby improving drilling rock-breaking efficiency. In commonly used oscillating screw drills, the moving valve is connected to the rotor. The rotor drives the moving valve to rotate eccentrically around the screw drill housing. This eccentric motion causes the flow area between the moving and stationary valve plates to change periodically, achieving hydraulic pulse oscillation.

[0005] For contact-type moving and stationary valves, a spring is designed into the stationary valve device to ensure that the mating surfaces of the stationary valve plate and the moving valve plate always remain in contact. This results in high friction between the moving and stationary valves, leading to a short service life. The screw drill shaft is subjected to significant axial force, rotational friction resistance, and bending moment, increasing the load stress on the screw drill shaft and bearing system, and reducing the overall efficiency of the screw drill. At the same time, because the axial force generated by the stationary valve acts on the moving valve and its shaft, the oscillation force generated by the pulse device only partially acts on the screw drill housing, reducing the screw drill's friction reduction and resistance reduction effect.

[0006] When the end face non-contact dynamic and static valves are in operation, wear of the ball bearings and universal joints in the screw drill transmission system, axial displacement of shaft-like parts such as the screw drill rotor, changes in the maximum and minimum flow area of ​​the drilling fluid through the dynamic and static valves, and the pulse pressure deviates from the design value. This affects the oscillation effect of the screw drill during long-term operation and may even lead to unnecessary tripping in and out of the drill string. Summary of the Invention

[0007] This application provides an oscillating screw drill bit with constant pulse force to solve the problem in related technologies where the pulse pressure acting on the screw drill bit housing is unstable, reducing the wear reduction and resistance reduction effect of the screw drill bit.

[0008] This application provides an oscillating screw drill bit with constant pulse force, comprising:

[0009] The drill bit body includes a housing and a shaft. The housing is a hollow tubular structure, and the shaft is located inside the housing and rotates eccentrically about the axis of the housing.

[0010] The pulse assembly includes a stationary valve fixed in the housing, a moving valve rotating in the housing, and a transmission rod connected to a shaft to drive the moving valve to rotate coaxially in the housing and maintain a constant axial distance between the moving valve and the stationary valve.

[0011] The stationary valve is provided with a stationary valve flow channel, and the moving valve is provided with a moving valve flow channel. The moving valve rotates relative to the stationary valve to periodically change the flow area between the stationary valve flow channel and the moving valve flow channel.

[0012] In some embodiments: the end of the moving valve near the transmission rod is provided with an internally meshing internal gear ring, and the end of the transmission rod near the moving valve is provided with an external gear that meshes with the internal gear ring and is axially slidably connected;

[0013] The external gear is eccentrically arranged in the internal gear ring and forms a radial clearance with the internal gear ring to communicate with the flow channel of the valve.

[0014] In some embodiments: the housing includes a motor housing and an anti-drop housing that are threaded together; the shaft includes a motor rotor located inside the motor housing and an anti-drop rod located inside the anti-drop housing and fixedly connected at one end to the motor rotor;

[0015] The transmission rod is provided with a threaded sleeve at one end away from the actuator valve, which is threaded to the other end of the anti-drop rod. The outer circumference of the threaded sleeve is provided with an annular boss, and the outer diameter of the annular boss is larger than the inner diameter of the anti-drop shoulder inside the anti-drop housing.

[0016] In some embodiments: the end of the moving valve near the stationary valve is provided with a flow plate parallel to the stationary valve, and the flow channel of the moving valve is located on the flow plate;

[0017] The flow plate and the internal gear ring are coaxial and integrally formed, and the top surface of the external gear and the bottom surface of the flow plate are pre-set with an axial gap.

[0018] In some embodiments: a positioning ring is fixedly provided inside the housing to axially position the moving valve, and the moving valve is coaxially rotatably connected inside the positioning ring;

[0019] The positioning ring is provided with a thrust ball bearing that is rotatably connected to the moving valve, and an adjusting washer that presses the outer ring of the thrust ball bearing and the positioning ring is provided between the thrust ball bearing and the stationary valve.

[0020] In some embodiments: the top of the housing is threadedly connected to an upper connector for axially fixing the static valve inside the housing, and the lower end face of the upper connector abuts against the static valve;

[0021] The upper connector is provided with an inlet hole and an outlet hole, and an oscillation amplification cavity is provided between the inlet hole and the outlet hole. The inner diameter of the oscillation amplification cavity is larger than the inner diameter of the outlet hole.

[0022] In some embodiments: the moving valve is located at the bottom of the stationary valve and is level with it, and the axial distance between the moving valve and the stationary valve is 0-6mm.

[0023] In some embodiments: the static valve flow channel includes a static valve center valve hole located at the center of the static valve, and a static valve eccentric valve hole located on the outer periphery of the static valve center valve hole;

[0024] The moving valve flow channel includes a moving valve center valve hole located at the center of the moving valve, and a moving valve eccentric valve hole located on the outer periphery of the moving valve center valve hole;

[0025] The stationary valve center valve hole is connected to the moving valve center valve hole, and the moving valve eccentric valve hole is intermittently connected to the stationary valve eccentric valve hole.

[0026] In some embodiments: the transmission rod is a ball cage universal coupling with adaptive length adjustment, one end of the ball cage universal coupling is rotatably connected to the shaft, and the other end of the ball cage universal coupling is rotatably connected to the moving valve.

[0027] In some embodiments, the other end of the ball cage universal coupling is provided with a flow passage communicating with the static valve flow channel.

[0028] The beneficial effects of the technical solution provided in this application include:

[0029] This application provides an oscillating screw drill with constant pulse force. The oscillating screw drill includes a drill body comprising a housing and a shaft. The housing is a hollow tubular structure, and the shaft is located inside the housing and rotates eccentrically around the housing's axis. A pulse assembly includes a stationary valve fixed inside the housing, a moving valve rotating inside the housing, and a transmission rod connected to the shaft to drive the moving valve to rotate coaxially within the housing, maintaining a constant axial distance between the moving and stationary valves. A stationary valve flow channel is provided on the stationary valve, and a moving valve flow channel is provided on the moving valve. The moving valve rotates relative to the stationary valve to periodically change the flow area between the stationary and moving valve flow channels.

[0030] Therefore, in this application, the stationary valve of the oscillating screw drill is fixed inside the housing, while the moving valve rotates within the housing. The moving valve can rotate around the center of the housing and is axially fixed relative to the housing. The mating end faces of the moving and stationary valves adopt a clearance fit with a constant clearance value. All the axial pulse thrust generated by the pulse assembly is transferred to the housing, improving the load on rod-like parts such as the screw drill shaft, extending the service life of the oscillating screw drill shaft and bearing system, and increasing the overall efficiency of the oscillating screw drill. Simultaneously, it eliminates the influence of component wear on the pulse force, further improving the axial oscillation effect of the screw drill during long-term operation. This application has a simple structure, can generate a larger axial oscillation force under the same pressure loss, and has a long service life for both the moving and stationary valves. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of an embodiment of this application;

[0033] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;

[0034] Figure 3 This is a top view of the static valve structure according to an embodiment of this application;

[0035] Figure 4 This is a top view of the valve structure according to an embodiment of this application;

[0036] Figure 5 This is a schematic diagram of the meshing state of the external gear and the internal gear ring in an embodiment of this application.

[0037] Figure label:

[0038] 1. Housing; 2. Shaft; 3. Pulse assembly; 4. Upper connector; 11. Motor housing; 12. Anti-drop housing; 21. Motor rotor; 22. Anti-drop rod; 31. Static valve; 31a. Static valve center valve hole; 31b. Static valve eccentric valve hole; 32. Dynamic valve; 32a. Dynamic valve center valve hole; 32b. Dynamic valve eccentric valve hole; 32c. Internal gear ring; 33. Transmission rod; 33a. External gear; 34. Positioning ring; 35. Thrust ball bearing; 36. Adjusting washer; 41. Liquid inlet; 42. Liquid outlet; 43. Oscillating amplification chamber. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] This application provides an oscillating screw drill bit with constant pulse force, which can solve the problem in related technologies where the pulse pressure acting on the screw drill bit housing is unstable, reducing the wear reduction and resistance reduction effect of the screw drill bit.

[0041] See Figure 1 and Figure 2 As shown, this application provides an oscillating screw drill bit with constant pulse force, comprising:

[0042] The drill string body includes a housing 1 and a shaft 2. The housing 1 is a hollow tubular structure, and the shaft 2 is located inside the housing 1 and rotates eccentrically around the axis of the housing 1. During normal drilling operations, the mud pumped out by the mud pump flows into the housing 1 through a bypass valve, creating a certain pressure difference between the inlet and outlet of the housing 1. This pressure difference drives the shaft 2 to rotate around the axis of the housing 1, and transmits the rotational speed and torque to the drill bit through a universal joint and a drive shaft, thereby realizing the drilling operation.

[0043] The pulse assembly 3 includes a stationary valve 31 fixed within the housing 1, a movable valve 32 rotating within the housing 1, and a transmission rod 33 connected to a shaft 2 to drive the movable valve 32 to rotate coaxially within the housing 1 and maintain a constant axial distance between the movable valve 32 and the stationary valve 31. The transmission rod 33 connects the shaft 2 and the movable valve 32, converting the eccentric rotation of the shaft 2 into driving the movable valve 32 to rotate coaxially within the housing 1 while maintaining a constant axial distance between the movable valve 32 and the stationary valve 31.

[0044] A stationary valve flow channel is provided on the stationary valve 31, and a moving valve flow channel is provided on the moving valve 32. The transmission rod 33 drives the moving valve 32 to rotate relative to the stationary valve 31, thereby periodically changing the flow area between the stationary valve flow channel and the moving valve flow channel to generate periodic axial pulse thrust. The axial pulse thrust is transmitted to the housing 1, converting the static friction between the downhole drill string and the well wall into dynamic friction, thus relieving the pressure on the drill string. Since the axial distance between the moving valve 32 and the stationary valve 31 is constant, the axial pulse thrust generated by the pulse assembly 3 is stable, improving the axial oscillation effect of the screw drill bit during long-term operation.

[0045] In this embodiment of the oscillating screw drill, the stationary valve 31 is fixed inside the housing 1, and the moving valve 32 rotates inside the housing 1. The moving valve 32 can rotate around the center of the housing 1 and is axially fixed relative to the housing 1. The mating end faces of the moving valve 32 and the stationary valve 31 adopt a clearance fit with a constant clearance value. The axial pulse thrust generated by the pulse assembly 3 is entirely transmitted to the housing 1, which improves the load on rod-like parts such as the screw drill rotor, extends the service life of the oscillating screw drill shaft 2 and bearing system, and improves the overall efficiency of the oscillating screw drill.

[0046] Meanwhile, the transmission rod 33 of the pulse assembly 3 can maintain a constant axial distance between the moving valve 32 and the stationary valve 31, eliminating the influence of wear on the pulse force caused by the shaft 2 and bearing system, and further improving the axial oscillation effect of the screw drill during long-term operation. This application has a simple structure, can generate a larger axial oscillation force under the same pressure loss, and has a long service life for both the moving and stationary valves.

[0047] In some alternative embodiments: see Figure 2 and Figure 5 As shown, this application embodiment provides an oscillating screw drill with constant pulse force. The oscillating screw drill has an internal gear ring 32c engaged with the drive rod 33 at one end of the moving valve 32. The drive rod 33 has an external gear 33a engaged with the internal gear ring 32c and axially slidingly connected at one end of the drive rod 33 near the moving valve 32. The external gear 33a is eccentrically arranged within the internal gear ring 32c and forms a radial clearance with the internal gear ring 32c that communicates with the flow channel of the moving valve.

[0048] In this embodiment, the transmission rod 33 is provided with an external gear 33a, and the actuating valve 32 is provided with an internal gear ring 32c that meshes with the external gear 33a. After the external gear 33a and the internal gear ring 32c mesh, they can not only convert the eccentric motion of the shaft 2 into driving the actuating valve 32 to rotate coaxially within the housing 1, but also allow the external gear 33a and the internal gear ring 32c to slide relative to each other in the axial direction. This prevents the shaft 2 from axially shifting within the housing 1 and changing the axial distance between the actuating valve 32 and the actuating valve 31, thereby maintaining the stability of the axial pulse thrust generated by the pulse assembly 3.

[0049] The external gear 33a is eccentrically arranged within the internal gear ring 32c and forms a radial clearance with the internal gear ring 32c to connect to the flow channel of the moving valve. This allows the external gear 33a to both rotate eccentrically within the internal gear ring 32c following the shaft 1 and drive the internal gear ring 32c to rotate coaxially within the housing 1. Furthermore, the radial clearance between the external gear 33a and the internal gear ring 32c connects to the flow channel of the moving valve, allowing drilling fluid to flow smoothly into the screw drill bit and drive its rotation.

[0050] In some alternative embodiments: see Figure 1 and Figure 2As shown, this application embodiment provides an oscillating screw drill with constant pulse force. The housing 1 of the oscillating screw drill includes a motor housing 11 and an anti-drop housing 12 that are threadedly connected to each other. The shaft 2 includes a motor rotor 21 located inside the motor housing 11, and an anti-drop rod 22 located inside the anti-drop housing 12 and fixedly connected at one end to the motor rotor 21.

[0051] The end of the transmission rod 33 furthest from the actuator valve 32 is provided with a threaded sleeve that is threadedly connected to the other end of the anti-fall rod 22. The outer circumference of the threaded sleeve is provided with an annular boss, the outer diameter of which is larger than the inner diameter of the anti-fall shoulder in the anti-fall housing 12. The anti-fall rod 22 is used to prevent the motor rotor 21 and the lower part connected to the motor rotor 21 from falling into the well when the connecting thread between the housings 1 of the screw drill fails.

[0052] In some alternative embodiments: see Figure 2 As shown in the embodiment of this application, an oscillating screw drill with constant pulse force is provided. One end of the moving valve 32 of the oscillating screw drill is provided with a flow plate parallel to the stationary valve 31, and the flow channel of the moving valve is located on the flow plate. The flow plate and the internal gear ring 32c are coaxial and integrally formed. The top surface of the external gear 33a and the bottom surface of the flow plate are pre-set with an axial clearance to prevent the shaft 2 from moving axially up and down in the housing 1 and changing the axial clearance between the moving valve 32 and the stationary valve 31.

[0053] A positioning ring 34 for an axially positioned moving valve 32 is fixedly installed inside the housing 1. The positioning ring 34 is threadedly fixed to the anti-drop housing 12 of the housing 1 to achieve axial positioning. The moving valve 32 is coaxially rotatably connected inside the positioning ring 34. A thrust ball bearing 35 is provided on the positioning ring 34 to rotatably connect the moving valve 32. An adjusting washer 36 is provided between the thrust ball bearing 35 and the stationary valve 31 to press the outer ring of the thrust ball bearing 35 against the positioning ring 34.

[0054] The thrust ball bearing 35 consists of an inner ring, an outer ring, and steel balls. It is lubricated and cooled by drilling fluid. The lower end face of the thrust ball bearing 35 mates with the upper end face of the positioning ring 34 to achieve axial positioning, and the upper end face of the thrust ball bearing 35 mates with the flow plate of the dynamic valve 32 to achieve axial positioning. The positioning ring 34 is designed with flow channel holes as a drainage channel for the drilling fluid.

[0055] The moving valve 32 is located at the bottom of the stationary valve 31 and is level with it. An adjusting washer 36 is provided between the thrust ball bearing 35 and the stationary valve 31 to adjust the axial clearance between the moving valve 32 and the stationary valve 31. The adjusting washer 36 is used to adjust the axial distance between the moving valve 32 and the stationary valve 31. The axial distance between the moving valve 32 and the stationary valve 31 can be selected from 0-6mm. The larger the axial distance between the moving valve 32 and the stationary valve 31, the smaller the axial pulse thrust generated by the pulse assembly 3. Therefore, the axial distance between the moving valve 32 and the stationary valve 31 can be flexibly set according to actual needs.

[0056] In some alternative embodiments: see Figure 2 As shown in the figure, this application embodiment provides an oscillating screw drill with constant pulse force. The top of the housing 1 of the oscillating screw drill is threadedly connected to an upper connector 4 that axially fixes a stationary valve 31 inside the housing 1. The lower end face of the upper connector 4 abuts against the stationary valve 31. The upper connector 4 is provided with an inlet hole 41 and an outlet hole 42. An oscillation amplification cavity 43 is provided between the inlet hole 41 and the outlet hole 42. The inner diameter of the oscillation amplification cavity 43 is larger than the inner diameter of the outlet hole 42.

[0057] In this embodiment, an oscillation amplification cavity 43 is provided inside the upper connector 4. This cavity 43 is located between the inlet hole 41 and the outlet hole 42 of the upper connector 4. The inner diameter of the oscillation amplification cavity 43 is larger than the inner diameter of the outlet hole 42. The oscillation amplification cavity 43 increases the area of ​​hydraulic pressure action, thereby increasing the axial oscillation force and reducing the tubing string pressure. This structure is suitable for enhanced parameter drilling and can further improve the mechanical drilling rate.

[0058] In some alternative embodiments: see Figure 3 and Figure 4 As shown, this application embodiment provides an oscillating screw drill with constant pulse force. The static valve flow channel of the oscillating screw drill includes a static valve center valve hole 31a located at the center of the static valve 31, and a static valve eccentric valve hole 31b located on the outer periphery of the static valve center valve hole 31a. The moving valve flow channel includes a moving valve center valve hole 32a located at the center of the moving valve 32, and a moving valve eccentric valve hole 32b located on the outer periphery of the moving valve center valve hole 32a.

[0059] The diameter of the stationary valve center valve hole 31a is the same as the diameter of the moving valve center valve hole 32a. The stationary valve center valve hole 31a and the moving valve center valve hole 32a are interconnected to allow drilling fluid to flow into the screw drill string and drive the motor rotor 21 to rotate. The eccentric valve hole 32b of the moving valve has the same radius of rotation as the eccentric valve hole 31b of the stationary valve. The eccentric valve hole 32b of the moving valve and the eccentric valve hole 31b of the stationary valve are intermittently connected to form an intermittent pulse channel for the drilling fluid to pass through.

[0060] The size and number of the eccentric valve holes 32b and 31b of the stationary valve determine the pulse frequency and the magnitude of the axial pulse thrust. The larger the diameter of the eccentric valve holes 32b and 31b of the stationary valve, the greater the axial pulse thrust generated by the pulse assembly 3. The more eccentric valve holes 32b and 31b of the stationary valve, the higher the frequency of the axial pulses generated by the pulse assembly 3.

[0061] In some alternative embodiments: This application provides an oscillating screw drill with constant pulse force. The transmission rod 33 of the oscillating screw drill is a ball cage universal coupling with adaptive length adjustment. One end of the ball cage universal coupling is rotatably connected to the shaft 2, and the other end is rotatably connected to the moving valve 32. The ball cage universal coupling connects between the shaft 2 and the moving valve 32, converting the eccentric rotation of the shaft 2 into driving the moving valve 32 to rotate coaxially within the housing 1, while maintaining a constant axial distance between the moving valve 32 and the stationary valve 31.

[0062] The length of the ball cage universal coupling is adaptably adjustable. When the shaft 2 moves upward in the housing 1, the length of the ball cage universal coupling can be adapted to shorten. When the shaft 2 moves downward in the housing 1, the length of the ball cage universal coupling can be adapted to lengthen. This avoids changing the axial clearance between the dynamic valve 32 and the static valve 31 when the shaft 2 moves upward in the housing 1, and maintains stable axial pulse thrust.

[0063] The length self-adaptive adjustment of the ball cage universal coupling is achieved through interconnected splined shafts and splined sleeves. The splined shafts, located within the splined sleeves, can both transmit torque and be freely adjusted in the length direction. A ball cage universal joint at one end of the splined shaft connects to the moving valve 32, and a ball cage universal joint at one end of the splined sleeve connects to the shaft 2. To ensure the drilling fluid flowing from the moving valve 32 smoothly enters the screw drill bit, a flow passage communicating with the stationary valve flow channel is provided at the end of the ball cage universal coupling near the moving valve 32.

[0064] Working principle:

[0065] This application provides an oscillating screw drill bit with constant pulse force. The screw drill bit utilizes drilling fluid pumped through a mud pump into the inner hole of the upper housing 1 of the screw drill bit. The drilling fluid enters the screw drill bit through the central valve hole 31a of the static valve 31 and the central valve hole 32a of the dynamic valve 32, thereby driving the motor rotor 21 to rotate. Simultaneously, the rotation of the motor rotor 21 drives the lower universal joint and drive shaft, and also drives the upper anti-fall rod 22 and drive rod 33 to rotate.

[0066] The transmission rod 33 converts the planetary eccentric motion of the motor rotor 21 into the rotation of the moving valve 32 around the central axis of the housing 1. This causes the flow area of ​​the drilling fluid flowing through the static valve 31 and the moving valve 32 to increase and decrease periodically, thereby generating periodic axial pulse pressure. This axial pulse pressure acts on the screw drill housing 1, causing the screw drill to produce periodic axial creep, converting the static friction between the downhole drill string and the well wall into dynamic friction, effectively transmitting drilling pressure and relieving the pressure on the drill string.

[0067] This application features a simple structure, possessing not only the power and safety of conventional screw drills, but also utilizing the screw drill's own surplus energy to supply the pulse assembly 3, thereby generating the pulse pressure wave required for axial oscillation. This ensures that the downhole drill string can smoothly transmit drilling pressure to the drill bit, improving drilling efficiency. Compared to other similar tools, this application reduces the axial force and rotational friction resistance on the screw drill shaft 2, extending the screw drill's service life and improving the overall efficiency of the screw drill, significantly contributing to improved drilling efficiency and shortened drilling cycles. Furthermore, the axial clearance between the dynamic valve 32 and the static valve 31 is unaffected by wear on the screw drill shaft 2 components, providing a constant and sustained pulse oscillation force to the screw drill.

[0068] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0069] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0070] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An oscillating screw drill with constant pulse force, characterized in that, include: The drill body includes a housing (1) and a shaft (2). The housing (1) is a hollow tubular structure, and the shaft (2) is located inside the housing (1) and rotates eccentrically around the axis of the housing (1). The pulse assembly (3) includes a stationary valve (31) fixed in the housing (1), a moving valve (32) rotating in the housing (1), and a transmission rod (33) connected to the shaft (2) to drive the moving valve (32) to rotate coaxially in the housing (1) and maintain a constant axial distance between the moving valve (32) and the stationary valve (31). The stationary valve (31) is provided with a stationary valve flow channel, and the moving valve (32) is provided with a moving valve flow channel. The moving valve (32) rotates relative to the stationary valve (31) to periodically change the flow area between the stationary valve flow channel and the moving valve flow channel. The moving valve (32) has an internal gear ring (32c) that meshes with the transmission rod (33) at one end, and the transmission rod (33) has an external gear (33a) that meshes with the internal gear ring (32c) and is axially slidably connected at one end. The external gear (33a) is eccentrically arranged in the internal gear ring (32c) and forms a radial clearance with the internal gear ring (32c) to communicate with the valve flow channel; The housing (1) includes a motor housing (11) and an anti-drop housing (12) that are threaded together. The shaft (2) includes a motor rotor (21) located inside the motor housing (11) and an anti-drop rod (22) located inside the anti-drop housing (12) and fixedly connected at one end to the motor rotor (21). The transmission rod (33) is provided with a threaded sleeve at one end away from the moving valve (32) and threadedly connected to the other end of the anti-drop rod (22). The outer circumference of the threaded sleeve is provided with an annular boss. The outer diameter of the annular boss is larger than the inner diameter of the anti-drop shoulder in the anti-drop housing (12). The moving valve (32) is located at the bottom of the stationary valve (31) and is level with it. The axial distance between the moving valve (32) and the stationary valve (31) is 0-6mm. The static valve flow channel includes a static valve center valve hole (31a) located at the center of the static valve (31), and a static valve eccentric valve hole (31b) located on the outer periphery of the static valve center valve hole (31a). The moving valve flow channel includes a moving valve center valve hole (32a) located at the center of the moving valve (32), and a moving valve eccentric valve hole (32b) located on the outer periphery of the moving valve center valve hole (32a). The stationary valve center valve hole (31a) and the moving valve center valve hole (32a) are interconnected, and the moving valve eccentric valve hole (32b) and the stationary valve eccentric valve hole (31b) are intermittently interconnected. The transmission rod (33) is a ball cage type universal coupling with adaptive length adjustment. One end of the ball cage type universal coupling is rotatably connected to the shaft (2), and the other end of the ball cage type universal coupling is rotatably connected to the moving valve (32).

2. The oscillating screw drill bit with constant pulse force as described in claim 1, characterized in that: The moving valve (32) is provided with a flow plate parallel to the stationary valve (31) at one end near the stationary valve (31), and the flow channel of the moving valve is located on the flow plate; The flow plate and the internal gear ring (32c) are coaxial and integrally formed, and the top surface of the external gear (33a) and the bottom surface of the flow plate are pre-set with an axial gap.

3. The oscillating screw drill bit with constant pulse force as described in claim 1, characterized in that: The housing (1) is fixedly provided with a positioning ring (34) for axially positioning the moving valve (32), and the moving valve (32) is coaxially rotatably connected in the positioning ring (34); The positioning ring (34) is provided with a thrust ball bearing (35) that is rotatably connected to the moving valve (32). An adjusting washer (36) that presses the outer ring of the thrust ball bearing (35) and the positioning ring (34) is provided between the thrust ball bearing (35) and the stationary valve (31).

4. The oscillating screw drill bit with constant pulse force as described in claim 3, characterized in that: The top of the housing (1) is threadedly connected to an upper connector (4) that axially fixes the static valve (31) inside the housing (1), and the lower end face of the upper connector (4) abuts against the static valve (31). The upper connector (4) is provided with an inlet hole (41) and an outlet hole (42). An oscillation amplification cavity (43) is provided between the inlet hole (41) and the outlet hole (42). The inner diameter of the oscillation amplification cavity (43) is larger than the inner diameter of the outlet hole (42).

5. The oscillating screw drill bit with constant pulse force as described in claim 1, characterized in that: The other end of the ball cage universal coupling is provided with a flow passage that communicates with the static valve flow channel.

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