Anti-interference cardan shaft assembly of screw drill

Abstract

The invention relates to the technical field of screw drilling tools, in particular to a screw drilling tool anti-interference cardan shaft assembly which comprises a connecting rod, the two ends of the connecting rod are universally and rotationally connected with rotor connectors through movable shafts correspondingly, the two ends of the connecting rod are provided with rod shifting fork bases correspondingly, and rod two-tooth shifting forks are integrally arranged on the rod shifting fork bases; the rod part two-tooth shifting fork comprises two rod part shifting teeth which are arranged at intervals in the circumferential direction, and the right-handed rotation stress surfaces or the left-handed rotation stress surfaces of the rod part shifting teeth are cambered surfaces; a joint shifting fork seat is arranged at the end part of the rotor joint, a joint two-tooth shifting fork is integrally arranged on the joint shifting fork seat, the joint two-tooth shifting fork comprises two joint shifting teeth which are circumferentially arranged at an interval, and the two joint shifting teeth and the two rod part shifting teeth are inserted in a cross shape and circumferentially abut against each other; due to the fact that the right-handed rotation stress face or the left-handed rotation stress face of the rod portion is the arc face, when the right-handed rotation stress face or the left-handed rotation stress face of the rod portion abuts against the plane of the connector shifting teeth and performs planetary motion, interference is not prone to occurring between the plane and the arc face, larger avoiding space exists, motion is smooth, torque transmission is flexible, and the service life is long.

Description

Technical Field

[0001] The invention relates to the technical field of screw drill tools, and in particular to an anti-interference universal shaft assembly of a screw drill tool. Background Art

[0002] Screw drill tools are the most commonly used downhole power tools for oil and gas drilling. They are mainly composed of bypass valves, motor assemblies, universal shaft assemblies and drive shaft assemblies. The universal shaft assembly is a key component of the screw drill tool transmission. It bears large stress loads. At present, the failure forms are mostly fracture and wear transition. The life of the universal shaft assembly directly affects the downhole service life of the screw drill tool. With the development of oil and gas exploration and development, more and more attention is focused on deep wells and ultra-deep wells, but with the increase in depth, the development environment of oil and gas tends to be complex. The compaction effect increases the hardness of the formation rock, and the formation rock is resistant to abrasion and hard rock is difficult to drill. The development of ultra-deep wells puts higher requirements on the universal shaft assembly of screw drill tools.

[0003] The invention patent with the patent number "CN119102518A" and the patent name "Universal shaft assembly for screw drill tools" provides a universal shaft assembly with relatively higher wear resistance, wear resistance, shear resistance, torsion resistance and long service life, which ensures that the screw drill tools meet the applicable conditions downhole and reduces the number of drilling and drilling times. However, due to the design defects of the fork structure of this technical solution, interference is likely to occur between the joint fork and the rod fork when they move relative to each other, resulting in uneven movement. As the working time increases, local damage is likely to occur, affecting the torque transmission effect and service life.

[0004] Therefore, in view of this design defect, an anti-interference screw drill universal shaft assembly is proposed to overcome the defects of the prior art. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an anti-interference universal shaft assembly for screw drills with reasonable structural design, flexible torque transmission and long service life.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: a screw drill anti-interference universal shaft assembly, including a connecting rod, both ends of the connecting rod are respectively connected to the rotor joint through a movable shaft, and both ends of the connecting rod are respectively provided with a rod fork seat, and the rod fork seat is integrally provided with a rod two-tooth fork, and the two rod two-tooth forks are arranged with the axis of the connecting rod as the center, and the two rod two-tooth forks include two rod teeth arranged at intervals in the circumferential direction, and each of the rod teeth includes a right-handed force-bearing surface of the rod and a rod The left-handed stress-bearing surface of the part, the two right-handed stress-bearing surfaces of the rod parts or the two left-handed stress-bearing surfaces of the rod parts are cambered surfaces; a joint fork seat is provided at the end of the rotor joint, and a joint two-tooth shift fork is integrally provided on the joint fork seat, and the joint two-tooth shift fork comprises two joint shift teeth arranged at intervals in the circumferential direction, and each of the joint shift teeth comprises a right-handed stress-bearing surface of the joint and a left-handed stress-bearing surface of the joint, and the two right-handed stress-bearing surfaces of the joints or the two left-handed stress-bearing surfaces of the joints are both planes, and the two joint shift teeth are cross-plugged and circumferentially abutted against each other with the two rod shift teeth.

[0007] As a preferred technical solution, the two rod shifting teeth are symmetrically arranged around the axis of the connecting rod, and a wear-resistant alloy layer is provided on the right-handed force-bearing surface of the rod and the left-handed force-bearing surface of the rod respectively.

[0008] As a preferred technical solution, the two joint shifting teeth are symmetrically arranged around the axis of the rotor joint, and a wear-resistant alloy layer is respectively provided on the right-handed stress-bearing surface of the joint and the left-handed stress-bearing surface of the joint.

[0009] As a preferred technical solution, the wear-resistant alloy layer is a tungsten-cobalt alloy layer.

[0010] As a preferred technical solution, the arc surface includes an inner concave avoidance arc located at the inner end of the rod tooth and an outer convex avoidance arc located at the outer end of the rod tooth, and a middle convex arc is connected between the inner concave avoidance arc and the outer convex avoidance arc, and the inner concave avoidance arc, the middle convex arc and the outer convex avoidance arc are smoothly transitioned.

[0011] As a preferred technical solution, the two right-handed force-bearing surfaces of the rod and the two left-handed force-bearing surfaces of the rod are both arc surfaces.

[0012] As a preferred technical solution, a rod shaft hole is provided on the rod fork seat along the axial direction, and a limit hole is provided in the radial direction of the rod fork seat and the rod shaft hole; a joint shaft hole is provided on the joint fork seat along the axial direction, and a limit cavity for accommodating the ball head end of the movable shaft is provided in the joint shaft hole; the ball head end of the movable shaft is located in the joint shaft hole, and the other end of the movable shaft is located in the rod shaft hole, and the movable shaft universally connects the rotor joint and the connecting rod together.

[0013] As a preferred technical solution, the axes of the limiting holes at both ends of the connecting rod are vertically arranged.

[0014] Due to the adoption of the above technical scheme, the anti-interference universal shaft assembly of the screw drill comprises a connecting rod, both ends of the connecting rod are universally connected to the rotor joint through a movable shaft, both ends of the connecting rod are respectively provided with a rod fork seat, a rod two-tooth fork is integrally provided on the rod fork seat, the two rod two-tooth forks are arranged with the axis of the connecting rod being rotated 90° around the axis of the connecting rod, the rod two-tooth fork comprises two circumferentially spaced rod teeth, each rod tooth comprises a right-handed force-bearing surface of the rod and a left-handed force-bearing surface of the rod, the two right-handed force-bearing surfaces of the rod or the two left-handed force-bearing surfaces of the rod are arc surfaces; a joint fork seat is provided at the end of the rotor joint, a joint two-tooth fork is integrally provided on the joint fork seat, the joint two-tooth fork comprises two The two joint shift teeth are arranged at circumferential intervals, and each joint shift tooth includes a right-handed stress-bearing surface of the joint and a left-handed stress-bearing surface of the joint. The two right-handed stress-bearing surfaces of the joints or the two left-handed stress-bearing surfaces of the joints are all planes, and the two joint shift teeth are cross-connected and circumferentially abutted against each other. The beneficial effect of the present invention is that since the right-handed stress-bearing surface of the rod part or the left-handed stress-bearing surface of the rod part of the rod shift tooth is an arc surface, when it abuts against the plane of the right-handed stress-bearing surface of the joint or the left-handed stress-bearing surface of the joint shift tooth and performs planetary motion, it is not easy for the plane and the arc surface to interfere with each other when they move with each other, there is a larger avoidance space, the movement is smoother, it is not easy to cause local damage, the structural design is reasonable, the torque transmission is flexible, and the service life is long. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following drawings are intended only to illustrate and explain the present invention, and are not intended to limit the scope of the present invention. Figure 1 It is a schematic diagram of the three-dimensional structure of the anti-interference universal shaft assembly of the screw drill according to the first embodiment of the present invention; Figure 2 1 is a front view of an anti-interference universal shaft assembly of a screw drill according to an embodiment of the present invention; Figure 3 yes Figure 2 Sectional view along AA direction; Figure 4 1 is a schematic structural diagram of a connecting rod of an anti-interference universal shaft assembly of a screw drill according to an embodiment of the present invention; Figure 5 yes Figure 4 B view in the figure; Figure 6 1 is a schematic structural diagram of a rotor joint of an anti-interference universal shaft assembly of a screw drill according to an embodiment of the present invention; Figure 7 yes Figure 2 The enlarged view of the part at I in the middle and the state diagram of the planet in motion; Figure 8It is a partial enlarged diagram of location I in the prior art and a state diagram of the planet in motion; Fig. 9 It is a schematic diagram of the three-dimensional structure of the anti-interference universal shaft assembly of the screw drill according to the second embodiment of the present invention; Fig.10 yes Fig. 9 Sectional view along CC direction; Fig.11 yes Fig.10 A partial enlarged view of the middle II; Fig.12 2 is a schematic structural diagram of a connecting rod of an anti-interference universal shaft assembly of a screw drill according to a second embodiment of the present invention; Fig.13 yes Fig.12 D-direction view in.

[0016] In the figure: 1-connecting rod; 11-rod fork seat; 12-rod shifting teeth; 13-right-handed force-bearing surface of the rod; 131-inner concave avoidance arc; 132-outer convex avoidance arc; 133-middle convex arc; 14-left-handed force-bearing surface of the rod; 15-limiting hole; 16-rod axial hole; 2-rotor joint; 21-joint fork seat; 22-joint shifting teeth; 23-right-handed force-bearing surface of the joint; 24-left-handed force-bearing surface of the joint; 25-joint axial hole; 26-limiting cavity. DETAILED DESCRIPTION

[0017] The present invention is further described below in conjunction with the accompanying drawings and examples. In the following detailed description, certain exemplary embodiments of the present invention are described only by way of illustration. Needless to say, those of ordinary skill in the art will recognize that the described embodiments may be modified in various ways without departing from the spirit and scope of the present invention. Therefore, the drawings and description are illustrative in nature and are not intended to limit the scope of protection of the claims.

[0018] Embodiment 1: like Figures 1 to 7As shown in common, the anti-interference universal shaft assembly of the screw drill comprises a connecting rod 1, both ends of the connecting rod 1 are universally connected to a rotor joint 2 through a movable shaft, both ends of the connecting rod 1 are respectively provided with a rod fork seat 11, and a rod two-tooth fork is integrally provided on the rod fork seat 11, and the two rod two-tooth forks are arranged with the axis of the connecting rod 1 rotating 90 degrees, and the rod two-tooth forks include two rod teeth 12 arranged at intervals in the circumferential direction, and each rod tooth 12 includes a rod right-handed force-bearing surface 13 and a rod left-handed force-bearing surface 14, and the two rod right-handed force-bearing surfaces 13 or the two rod left-handed force-bearing surfaces 14 are arc surfaces; the end of the rotor joint 2 A joint fork seat 21 is provided on the joint fork seat 21, and a joint two-tooth fork is integrally provided on the joint fork seat 21. The joint two-tooth fork includes two joint teeth 22 arranged at intervals in the circumferential direction, and each joint tooth 22 includes a joint right-handed force-bearing surface 23 and a joint left-handed force-bearing surface 24. The two joint right-handed force-bearing surfaces 23 or the two joint left-handed force-bearing surfaces 24 are both planes, and the two joint teeth 22 are cross-connected and circumferentially pressed against the two rod teeth 12; the working state of the universal shaft assembly provided by the present invention is to convert the planar planetary motion of the screw drill motor rotor into the fixed-axis operation of the transmission shaft, and at the same time transmit the working torque of the motor to the transmission shaft and the drill bit. Therefore, the two rotor joints 2 of the universal shaft make planetary rotation around the central connecting rod 1, and the contact surfaces of the four cross petals of the two movable twists move in an internal angle of 3° around the axis of the connecting rod 1. The prior art such as Figure 8 As shown, the force-bearing surfaces of the rod shifting tooth 12 and the joint shifting tooth 22 are both planes, which will interfere with the edge corners of the end and the inner edge corners during planetary motion, and the operation is not flexible; while in the present invention, since the right-handed force-bearing surface 13 of the rod shifting tooth 12 or the left-handed force-bearing surface 14 of the rod portion is changed from the original plane to an arc surface, when it is against the plane of the right-handed force-bearing surface 23 of the joint or the left-handed force-bearing surface 24 of the joint shifting tooth 22 and performs planetary motion, the plane smoothly transitions in the arc surface, rather than the plane moving in the plane, and the force is more uniform during the movement. It is not easy for the plane and the arc surface to interfere with each other when they move with each other, there is a larger avoidance space, the movement is smoother, it is not easy to cause local damage, the structural design is reasonable, the torque transmission is flexible, and the service life is long.

[0019] like Figure 3 and Figure 4 As shown together, the two rod parts and the two-tooth shift forks are arranged with the axis of the connecting rod 1 rotated 90° as the center. Compared with the symmetrical arrangement of the shift teeth at both ends of the connecting rod 1 in the prior art, the strength is higher, the operation is more stable during planetary motion, and the service life is further improved.

[0020] like Figure 4 and Figure 5As shown together, the two rod shift teeth 12 are symmetrically arranged with respect to the axis center of the connecting rod 1, and the right-handed force-bearing surface and the left-handed force-bearing surface are provided with wear-resistant alloy layers respectively. The circumferential cross-section of the rod shift teeth 12 occupies about 87°, and the gap between the two rod shift teeth 12 occupies about 93° in the circumferential direction. When the universal joint assembly rotates right, the corresponding right-handed force-bearing surfaces of the rod shift teeth 12 and the joint shift teeth 22 abut against each other, and when the universal joint assembly rotates left, the corresponding left-handed force-bearing surfaces of the rod shift teeth 12 and the joint shift teeth 22 abut against each other.

[0021] like Figure 6 As shown, the two joint teeth 22 are symmetrically arranged with respect to the axis center of the rotor joint 2, and the joint right-handed force surface 23 and the joint left-handed force surface 24 are provided with wear-resistant alloy layers respectively. The circumferential cross section of the joint teeth 22 occupies about 87°, and the gap between the two joint teeth 22 occupies about 93° in the circumferential direction. After the joint teeth 22 are matched with the rod teeth 12, a certain gap is left for matching the planetary motion. The left-handed force surface and the right-handed force surface of the rod teeth 12 and the joint teeth 22 are sintered with tungsten-cobalt alloy layers, which greatly improves the wear resistance.

[0022] like Figure 7 As shown, the arc surface includes a concave avoidance arc 131 located at the inner end of the rod tooth 12 and a convex avoidance arc 132 located at the outer end of the rod tooth 12, and a middle convex arc 133 is connected between the concave avoidance arc 131 and the convex avoidance arc 132, and the concave avoidance arc 131, the middle convex arc 133 and the convex avoidance arc 132 are smoothly transitioned. The concave avoidance arc 131 is used to avoid the edge edges of the end face of the joint tooth 22, and the concave avoidance arc 131 is a 90° arc surface with a radius R. The convex avoidance arc 132 is used to avoid the internal edge edges of the joint tooth 22, and the convex avoidance arc 132 is a 90° arc surface with a radius r, R is approximately one-sixth of the length of the rod tooth 12, and r is approximately one-eighth of the length of the rod tooth 12. The main function of the middle convex arc 133 is to smoothly transition between the concave avoidance arc 131 and the convex avoidance arc 132. The size of the arc is determined according to actual conditions, as long as it convexes toward the force-bearing surface of the joint tooth 22 that is in contact with it. This ensures that the joint tooth 22 and the rod tooth 12 can interact with each other without interfering with each other, thereby ensuring the flexibility of torque transmission.

[0023] like Figure 3As shown, a rod shaft hole 16 is provided on the rod fork seat 11 along the axial direction, and a limiting hole 15 is provided in the radial direction of the rod fork seat 11 and the rod shaft hole 16; a joint shaft hole 25 is provided on the joint fork seat 21 along the axial direction, and a limiting cavity 26 for accommodating the ball head end of the movable shaft is provided in the joint shaft hole 25; the ball head end of the movable shaft is located in the joint shaft hole 25, and the other end of the movable shaft is located in the rod shaft hole 16, and the movable shaft universally connects the rotor joint 2 and the connecting rod 1 together. The movable shaft is not shown in the figure, and it can be used with the existing technology. A ball head is provided at one end of the movable shaft, and the ball head is located in the limiting cavity 26, so that one end of the movable shaft is limited to the rotor joint 2; the other end of the movable shaft is symmetrically provided with a blind hole in the radial direction, and a limiting rivet passes through the limiting hole 15 and connects with the blind hole, so that the other end of the movable shaft is limited to the connecting rod 1.

[0024] like Figure 1 and Figure 3 As shown in the figure, the axes of the limiting holes 15 at both ends of the connecting rod 1 are vertically arranged. The axes of the limiting holes 15 at both ends of the connecting rod 1 are perpendicular to each other, which improves the strength of the connecting rod 1 and prolongs the service life of the connecting rod 1 compared to the axes being parallel to each other.

[0025] In this embodiment, only the right-handed force-bearing surface or the left-handed force-bearing surface is used to improve the arc surface. Because in actual use, the right-handed method is often adopted, so there is no need to perform additional arc surface processing on the force-bearing surface on the other side, which reduces the processing intensity and saves processing costs. Of course, if it is used in a left-handed manner, you can choose to process the left-handed force-bearing surface alone.

[0026] Embodiment 2: This embodiment is basically the same as the first embodiment, except that Figures 9 to 13 As shown together, the two right-handed force-bearing surfaces 13 of the rod parts and the two left-handed force-bearing surfaces 14 of the rod parts are all cambered surfaces. In this embodiment, both the right-handed force-bearing surfaces and the left-handed force-bearing surfaces are improved with cambered surfaces. Although this processing has an extra step, it is more flexible in later use. Whether it is left-handed or right-handed, it can reduce interference and ensure the flexibility of torque transmission.

[0027] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A screw drill anti-interference universal shaft assembly, comprising a connecting rod (1), characterized in that: The two ends of the connecting rod (1) are universally rotatably connected to the rotor joint (2) via a movable shaft. The two ends of the connecting rod (1) are respectively provided with a rod fork seat (11). The rod fork seat (11) is integrally provided with a rod two-tooth fork. The two rod two-tooth forks are arranged 90 degrees around the axis of the connecting rod (1). The rod two-tooth forks include two rod teeth (12) arranged at intervals in the circumferential direction. Each of the rod teeth (12) includes a rod right-handed force-bearing surface (13) and a rod left-handed force-bearing surface (14). The two rod right-handed force-bearing surfaces (13) or the two rod left-handed force-bearing surfaces (14) are arranged at the same time. The left-handed force-bearing surface (14) of the rod is an cambered surface; a joint fork seat (21) is provided at the end of the rotor joint (2); a joint two-tooth fork is integrally provided on the joint fork seat (21); the joint two-tooth fork comprises two joint teeth (22) arranged at intervals in the circumferential direction; each of the joint teeth (22) comprises a joint right-handed force-bearing surface (23) and a joint left-handed force-bearing surface (24); the two joint right-handed force-bearing surfaces (23) or the two joint left-handed force-bearing surfaces (24) are both planes; the two joint teeth (22) and the two rod teeth (12) are cross-connected and circumferentially abutted against each other.

2. The anti-interference universal shaft assembly for screw drill according to claim 1, characterized in that: The two rod shifting teeth (12) are symmetrically arranged about the axis of the connecting rod (1), and a wear-resistant alloy layer is respectively provided on the right-handed force-bearing surface (13) of the rod and the left-handed force-bearing surface (14) of the rod.

3. The anti-interference universal shaft assembly for screw drill according to claim 2, characterized in that: The two joint shifting teeth (22) are symmetrically arranged about the axis center of the rotor joint (2), and a wear-resistant alloy layer is respectively provided on the right-handed force-bearing surface (23) of the joint and the left-handed force-bearing surface (24) of the joint.

4. The anti-interference universal shaft assembly for screw drill according to claim 2 or 3, characterized in that: The wear-resistant alloy layer is a tungsten-cobalt alloy layer.

5. The anti-interference universal shaft assembly for screw drill according to claim 1, characterized in that: The arc surface comprises an inner concave avoidance arc (131) located at the inner end of the rod shifting tooth (12) and an outer convex avoidance arc (132) located at the outer end of the rod shifting tooth (12); a middle convex arc (133) is connected between the inner concave avoidance arc (131) and the outer convex avoidance arc (132); and the inner concave avoidance arc (131), the middle convex arc (133) and the outer convex avoidance arc (132) are smoothly transitioned.

6. The anti-interference universal shaft assembly for screw drill according to claim 1, characterized in that: The two right-handed force-bearing surfaces (13) of the rod portion and the two left-handed force-bearing surfaces (14) of the rod portion are both arc surfaces.

7. The anti-interference universal shaft assembly for screw drill according to claim 1, characterized in that: A rod shaft hole (16) is provided on the rod fork seat (11) along the axial direction, and a limit hole (15) is provided in the radial direction of the rod fork seat (11) and the rod shaft hole (16); a joint shaft hole (25) is provided on the joint fork seat (21) along the axial direction, and a limit cavity (26) for accommodating the ball head end of the movable shaft is provided in the joint shaft hole (25); the ball head end of the movable shaft is located in the joint shaft hole (25), and the other end of the movable shaft is located in the rod shaft hole (16), and the movable shaft universally connects the rotor joint (2) and the connecting rod (1) together.

8. The anti-interference universal shaft assembly for screw drill according to claim 7, characterized in that: The axes of the limiting holes (15) at both ends of the connecting rod (1) are arranged vertically.

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