CN211614418U

CN211614418U - Torque overload protection device for drilling

Info

Publication number: CN211614418U
Application number: CN201922158701.9U
Authority: CN
Inventors: 张中伟; 任俊飞; 鱼鹏飞; 张博晖; 代争争; 程洋洋; 吴立辉; 武照云
Original assignee: Henan University of Technology
Current assignee: Henan University of Technology
Priority date: 2019-12-05
Filing date: 2019-12-05
Publication date: 2020-10-02
Anticipated expiration: 2029-12-05

Abstract

The utility model relates to a drilling processing safety protection field, concretely relates to moment of torsion overload protection device for drilling. The overload protection device includes: an outer cylinder; the inner rotating part is coaxially arranged with the outer cylinder at a radial interval, and at least one end of the inner rotating part is positioned in the outer cylinder; the annular groove is arranged on the peripheral surface of the inner rotating part, one of the outer cylinder and the inner rotating part is connected with a rotary power source, and the other one is connected with the cutter; the grooves are formed in the bottom of the annular groove and at least three grooves are uniformly distributed in the circumferential direction; the sleeve is fixedly arranged on the outer barrel, radially penetrates through the barrel wall of the outer barrel and is inserted into the annular groove in a matching manner, and at least three grooves which correspond to part or all of the grooves in a one-to-one manner are uniformly distributed in the sleeve along the circumferential direction; the locking piece is assembled in the sleeve in a sliding mode, and the radial inner end of the locking piece penetrates out of the sleeve and can be inserted into the corresponding groove; an elastic member applying an elastic force toward the groove to the locking member; in the circumferential direction of the inner rotating part, the inner end of the locking piece and/or the groove wall of the groove are/is provided with a slope surface.

Description

Torque overload protection device for drilling

Technical Field

The utility model relates to a drilling processing safety protection field, concretely relates to moment of torsion overload protection device for drilling.

Background

The safety of the existing drilling equipment is low, when drilling is difficult, the drilling torque can be increased, and when the drilling torque exceeds the limit borne by a drill bit, the drill bit can be broken. In addition, after the drilling torque is increased, the load power of a motor for driving the drill bit to rotate is increased, the drill bit is easy to be clamped and does not rotate or the rotating speed is rapidly reduced, so that the current of the motor is suddenly increased to overheat, and even the motor is burnt out.

The overload protection device is a common safety component designed for the above situations, and the existing overload protection devices generally have three types: firstly, the cutter is controlled to retreat at a set distance or time at intervals to prevent the cutter from being stuck, and the defects are that the load is changed rapidly and the reaction is slow, so that the cutter retreats after being stuck for a certain time, and the cutter or a motor is still damaged; secondly, a motor overcurrent protection device is added, when the current of the motor is increased suddenly, the power supply is cut off, the motor is protected, and the defects that the cutters such as a drill bit and the like cannot be effectively protected; thirdly, a torsion spring type torque protection device, namely a device similar to a torque switch is additionally arranged, and when the drilling torque reaches a set value, the motor is controlled to reversely rotate to retract the tool.

The existing three overload protection devices can protect the cutter and/or the motor to a certain extent, but as can be seen from the above description, the three overload protection devices all need to be equipped with an electrical control system, and need to modify or upgrade the electrical control system of the drilling equipment, which results in relatively high cost. In addition, transient abnormality such as rapid change of output torque due to uneven material of the workpiece or hard spot cannot be known in time and protection is started.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a moment of torsion overload protection device for drilling to the overload protection device who solves among the prior art needs to be equipped with electrical control system and leads to the higher technical problem of drilling equipment overall cost.

In order to achieve the above object, the utility model discloses torque overload protection device for drilling's technical scheme is: a drilling torque overload protection device, comprising:

an outer cylinder;

the inner rotating part is coaxially arranged with the outer cylinder at a radial interval, and at least one end of the inner rotating part is positioned in the outer cylinder;

the annular groove is arranged on the peripheral surface of the inner rotating part, one of the outer cylinder and the inner rotating part is connected with a rotary power source, and the other one is connected with the cutter;

the grooves are arranged at the bottom of the ring groove and are at least three in number along the circumferential direction;

the sleeve is fixedly arranged on the outer barrel, radially penetrates through the barrel wall of the outer barrel and is inserted into the annular groove in a matching manner, and at least three grooves which correspond to part or all of the grooves in a one-to-one manner are uniformly distributed in the sleeve along the circumferential direction;

the locking piece is assembled in the sleeve in a sliding mode, and the radial inner end of the locking piece penetrates out of the sleeve and can be inserted into the corresponding groove;

the elastic piece applies elastic acting force towards the groove to the locking piece, so that the locking piece can be in circumferential stop fit with the corresponding groove within a set drilling torque range;

in the circumferential direction of the inner rotating member, the inner end of the locking member and/or the groove wall of the groove are/is provided with a slope surface, so that the locking member reversely pushes the elastic member and is separated from the groove when the torque exceeds the set drilling torque range.

The utility model has the advantages that: the locking piece is pressed into the groove by the elastic piece, when the drilling tool is used within a set drilling torque range, the locking piece is in blocking fit with the groove, meanwhile, the locking piece is located in the sleeve, the sleeve is fixed in the outer barrel, the anti-rotation fit between the outer barrel and the inner rotating piece is achieved, and the rotary power source drives the tool to rotate through the overload protection device. When the cutter is blocked or the drilling torque is greater than the set drilling torque, the locking piece overcomes the acting force of the elastic piece and is separated from the groove, the outer barrel and the inner rotating piece are separated, the rotary power source cannot drive the cutter to rotate, the cutter is prevented from being damaged, and meanwhile, the rotary power source is effectively protected. Furthermore, the utility model discloses an among the overload protection device, the sleeve inserts in the annular, under the prerequisite that does not influence normal work, has realized the axial positioning between urceolus and the interior rotation piece. The utility model discloses an overload protection device has just realized overload protection through mechanical structure, need not be equipped with electrical control system, and overall cost is lower.

As a further optimized scheme, the overload protection device further comprises a thread adjusting piece, threads are spirally arranged in the sleeves, the thread adjusting piece inwards pushes the corresponding elastic piece, and the set drilling torque range can be changed by rotating the thread adjusting piece. The screw thread regulating part can push away the elastic component in order to push away the locking piece indirectly, and the screw thread regulating part can change the compression degree of elastic component moreover, adjusts and sets for drilling moment of torsion scope, has enlarged the utility model discloses an overload protection device's application range.

As a further optimized solution, the threaded adjusting member is an adjusting screw, and the head of the adjusting screw is located outside the sleeve. The head of adjusting screw is located telescopic outside, conveniently adjusts.

As a further optimized scheme, the wall of the outer cylinder is provided with radial through holes, the sleeves penetrate into the corresponding radial through holes, the overload protection device further comprises a gland which presses the inner end of each sleeve in the annular groove, and the gland is fixedly arranged on the outer cylinder. The press cover presses the outer end of the sleeve, the ring groove presses the inner end of the sleeve, the sleeve is integrally fixed in the outer barrel, and the installation mode is simple and convenient.

As a further optimized scheme, the annular groove is in a trapezoid shape with a small inner part and a large outer part, and the inner end of the sleeve is a conical end matched with the annular groove in shape. The taper end is adopted to facilitate the sleeve to be worn and installed.

As a further optimized scheme, the outer cylinder is provided with a main shaft in a non-penetrating manner, one end of the main shaft is used for being connected with the rotary power source, the other end of the main shaft penetrates into the inner rotating part, and the inner rotating part is connected with the corresponding end of the main shaft in a relatively rotatable manner through a bearing. After being connected through the bearing in a relatively rotatable manner, the bearing can actually position the axial position between the outer cylinder and the inner rotating member.

As a further optimized scheme, the main shaft is provided with a positioning shaft shoulder positioned in the outer cylinder, and the positioning shaft shoulder is in axial stop fit with an inner ring of the bearing; and a bearing end cover is fixed at the end part of the lower end of the main shaft through a hexagon bolt, and the bearing end cover is provided with an annular stop tip matched with the outer ring at the other end of the bearing in a stop way. The bearing can be axially positioned through the matching of the bearing end cover and the positioning shaft shoulder, meanwhile, the bearing end cover is provided with an annular stopping tip, the bearing end cover not only axially stops the outer ring of the bearing, but also cannot drive the inner rotating part to rotate through the outer ring of the bearing.

As a further optimized scheme, the inner rotating piece is sleeved outside the bearing in the direction of the main shaft, the torque overload protection device comprises a positioning rod piece, the positioning rod piece is arranged on the outer cylinder and extends along the axial direction of the outer cylinder, the end part of the positioning rod is used for being matched with the inner rotating piece in a blocking mode, and the axial position of the inner rotating piece is limited, so that the annular groove in the inner rotating piece and the locking piece in the outer cylinder are arranged at the same axial position. After the positioning rod piece is arranged, the axial position of the internal rotating piece can be limited, and the ring groove and the locking piece can be accurately matched.

As a further optimized scheme, a positioning threaded hole is formed in the outer barrel, and the positioning rod piece is a threaded piece screwed in the positioning threaded hole. The positioning rod piece is a threaded piece, the position can be conveniently adjusted, and the positioning rod piece can be detached after assembly is completed and is convenient to use.

As a further optimized scheme, the locking piece is a locking ball, and the groove is a hemispherical groove matched with the spherical shape of the locking ball. The locking ball and the hemispherical groove are used for blocking, so that the processing is more convenient.

Drawings

Fig. 1 is a schematic view of an embodiment of the torque overload protection device for drilling of the present invention;

description of reference numerals: 1. an inner barrel; 1-1, Morse taper hole; 1-2, a groove; 1-3, ring grooves; 2. an outer cylinder; 2-1, positioning the threaded hole; 3. a main shaft; 3-1, Morse taper axis; 3-2, positioning a shaft shoulder; 4. a flat bond; 5. a bearing; 6. a sleeve; 7. a gland; 8. fastening screws; 9. an adjusting screw; 10. a pressure spring; 11. a steel ball; 12. a shaft sleeve; 13. a bearing end cap; 14. a spring washer; 15. a hexagon bolt.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention, i.e., the described embodiments are only some, but not all embodiments of the invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiment of the present invention, all other embodiments obtained by the person skilled in the art without creative work belong to the protection scope of the present invention.

It is noted that relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The features and properties of the present invention are described in further detail below with reference to examples.

The utility model discloses a moment of torsion overload protection device for drilling's concrete embodiment:

as shown in fig. 1, the torque overload protection device for drilling is an overload protection device, and the overload protection device of the present invention is connected between a rotary power source (such as a motor) and a cutter when in use, and plays a role of torque overload protection.

The overload protection device specifically comprises an outer barrel 2, an inner barrel 1 and a main shaft 3, wherein the main shaft 3 sequentially drives the outer barrel 2 and the inner barrel 1 to rotate when the overload protection device is used.

The structure of the outer cylinder 2 is shown in fig. 1, the whole outer cylinder 2 is in a cylinder shape with an open lower end, the main shaft 3 is arranged above the outer cylinder 2 in a penetrating way along the axial direction of the outer cylinder 2, and the main shaft 3 is in rotation stopping fit with the outer cylinder 2 through a flat key 4. The part of the main shaft 3 above the outer cylinder 2 is provided with a Morse taper shaft 3-1, and when the spindle is used, the Morse taper shaft 3-1 is assembled with a Morse taper hole at the end part of a main shaft of a machine tool and can be driven by the main shaft of the machine tool to rotate. The main shaft 3 is provided with a positioning shaft shoulder 3-2 positioned inside the outer cylinder 2.

The structure of the inner cylinder 1 is shown in figure 1, the through hole in the middle of the inner cylinder 1 comprises an upper straight hole and a lower Morse taper hole 1-1, the Morse taper hole 1-1 is used for connecting a drill chuck, and is indirectly connected with a tool such as a drill bit and the like through the drill chuck. The lower end of the main shaft 3 is inserted into a straight hole in the inner cylinder 1 and is axially fixed by a bearing. Specifically, two bearings 5 are sleeved from top to bottom outside the main shaft 3, and the two bearings 5 are separated by a sleeve 12. The inner ring of the upper bearing 5 is propped against the positioning shaft shoulder 3-2, the outer ring of the lower bearing 5 is propped against the bearing end cover 13, and the bearing end cover 13 is fixedly arranged at the lower end part of the main shaft 3 through a hexagon bolt 15. In order to ensure the firmness and stability of the installation, a spring washer 14 is arranged between the hexagon bolt 15 and the bearing end cover 13. The outer periphery of the bearing end cover 13 is provided with a flange which is pressed against the outer ring of the lower bearing 5. As can be seen from fig. 1, the flange has a small size, so as to form an annular stop tip, and the part of the bearing end cover 13 that blocks the bearing 5 is made into a tip size, so as to ensure the axial stop of the bearing 5 and prevent the main shaft 3 from driving the inner cylinder 1 to rotate through the bearing end cover 13 and the outer ring of the bearing 5.

Moreover, as can be seen from fig. 1, the outer peripheral surface of the inner cylinder 1 is provided with ring grooves 1-3, the ring grooves 1-3 are arranged around a circle, the ring grooves 1-3 are in a flaring shape with a narrow inner part and a wide outer part, and the cross section is trapezoidal. The bottom of the ring groove 1-3 is provided with a semicircular groove 1-2, wherein six grooves 1-2 are uniformly distributed along the circumferential direction, and the groove wall of the groove 1-2 is semicircular.

The utility model discloses in, in order to make urceolus 2 can drive inner tube 1 and rotate, realize the disconnection simultaneously when the moment of torsion transships. As shown in fig. 1, three radial through holes are formed in the wall of the outer cylinder 2, the three radial through holes are uniformly distributed along the circumferential direction of the outer cylinder 2, a sleeve 6 is fixedly arranged in each radial through hole in a penetrating manner, the radial inner end of the sleeve 6 is a conical end, and the shape and the size of the sleeve are consistent with those of the ring grooves 1-3, so that adaptive insertion is realized, and the ring grooves 1-3 and the sleeve 6 are guaranteed to be in stop fit in the axial direction of the inner cylinder 1. As shown in fig. 1, in order to ensure that the inner end of the sleeve 6 is held pressed against the ring grooves 1 to 3, in this embodiment, press fitting is performed with a press cover 7. In order to install the gland 7, an installation platform is arranged on the periphery of the outer cylinder 2 corresponding to the position of each sleeve 6, and the installation platform is provided with an installation plane. During assembly, the gland 7 is pressed on the mounting plane and is fastened and mounted by the fastening screw 8.

The existence of the sleeve 6 can ensure that the inner cylinder 1 cannot fall downwards, and meanwhile, the existence of the sleeve 6 and the ring grooves 1-3 cannot influence the rotation stopping fit and the synchronous rotation fit between the inner cylinder 1 and the outer cylinder 2.

In order to enable the outer cylinder 2 to drive the inner cylinder 1 to rotate, as shown in fig. 1, a steel ball 11, a pressure spring 10 and an adjusting screw 9 are sequentially installed in the sleeve 6 from inside to outside along the extending direction of the sleeve 6, wherein the steel ball 11 is slidably assembled in the sleeve 6, the inner end of the steel ball 11 can be embedded in the groove 1-2, and the steel ball 11 can simultaneously cross the groove 1-2 and the sleeve 6. The adjusting screw 9 is screwed in the sleeve 6, the adjusting screw 9 applies elastic force pushing the steel ball 11 to the pressure spring 10, the compression degree of the pressure spring 10 can be changed by rotating the adjusting screw 9, and the elastic force applied to the steel ball 11 is changed. Wherein, as shown in fig. 1, the head of the adjusting screw 9 is positioned outside the outer cylinder 2 for easy adjustment.

As shown in fig. 1, a positioning threaded hole 2-1 is formed at one end of the outer cylinder 2 for axial positioning when the inner cylinder 1 is assembled. The specific use mode is as follows, during assembly, threaded parts such as a screw rod or a bolt or a screw are inserted into the positioning threaded hole 2-1, the length of the threaded parts penetrating out of the outer cylinder 2 is adjusted, when the inner cylinder 1 is sleeved outside the bearing 5 from bottom to top, when the top of the inner cylinder 1 is in contact with and stopped by the end part of the threaded parts, the inner cylinder 1 is installed in place, and at the moment, the annular grooves 1-3 in the inner cylinder 1 and the sleeve 6 are in the same axial position. The threaded member can be removed after assembly is complete. In this embodiment, the screw member forms a positioning rod member, and in other embodiments, the positioning rod member may have other structures, such as a rod body welded to the outer cylinder. Or in other embodiments, the threaded hole can be eliminated, and the inner cylinder can be ensured to be installed in place by measuring the distance between the upper end face of the inner cylinder and the upper end face of the bearing.

The utility model discloses a use as follows: during installation, the steel balls 11 are pressed into the grooves 1-2 by the pressure spring 10, three steel balls 11 are uniformly distributed along the circumferential direction, three of the six grooves 1-2 are matched with the steel balls 11, and the other three are idle. After the components are assembled, the steel ball 11 is pressed into the groove 1-2 by the pressure spring 10, and the sleeve 6 is pressed into the ring groove 1-3. During drilling, when the drilling torque is within the overload protection torque range, static friction force is generated between the steel ball 11 and the groove wall of the groove 1-2, the static friction force generates static friction moment, and the static friction moment drives the inner cylinder 1 to coaxially and synchronously rotate along with the outer cylinder 2. When drilling difficulty or drill bit jamming occurs, drilling torque is increased sharply, when the torque is larger than static friction torque, the steel ball 11 slides out of the groove 1-2 of the inner cylinder 1 and slides to the next adjacent groove 1-2 along the ring groove 1-3, and at the moment, power is separated between the inner cylinder 1 and the outer cylinder 2 and abnormal movement sound is sent out to remind an operator to immediately take intervention protection measures.

In this embodiment, the steel ball 11 functions to lock the inner cylinder 1 and the outer cylinder 2, thereby forming a lock ball. The locking ball and the hemispherical groove 1-2 are both provided with a slope surface, so that the direction change movement can be realized.

The locking balls form locking members capable of locking the inner barrel 1 and the outer barrel 2, and in other embodiments, the locking members may be locking rods with or without bulbs. The shape of the groove can be changed, but the requirement is met, in the circumferential direction of the inner cylinder, at least one of the end part of the locking piece and the groove wall of the groove is provided with a slope surface, the slope surface can be an arc-shaped or spherical surface, and can also be a plane extending in a common inclined manner, so that the circumferential force between the groove and the locking piece can be converted into the radial force pushing the locking piece to move.

In the embodiment, one end of the inner cylinder 1 is provided with the bearing 5, and the other end of the inner cylinder is provided with the morse taper hole 1-1 for installing the cutter. The inner barrel 1 forms the inner rotor.

In this embodiment, the positioning shoulder 3-2 and the bearing end cover 13 on the main shaft 3 are used for axially fixing the bearing 5, and in other embodiments, an inner ring platform can be arranged on the inner cylinder 1 to be matched with the positioning shoulder for axially fixing the bearing. In other embodiments, the bearings may be eliminated.

In this embodiment, annular 1-3 are the trapezoidal of big-end-up inside, and the inner shape of sleeve 6 is unanimous, and in other embodiments, the shape of annular can change according to actual conditions, and correspondingly, telescopic shape also needs to follow and changes.

In the embodiment, the sleeve 6 is fixed by matching the ring grooves 1-3 with the gland 7, and in other embodiments, the gland can be eliminated by screwing the sleeve on the wall of the outer cylinder.

In this embodiment, adjusting screw 9's head is located the outside of sleeve 6, conveniently operates, and adjusting screw 9 has formed the screw thread regulating part, and in other embodiments, the screw thread regulating part can be for adorning soon the screw rod in the sleeve, and the screw rod submerges completely in the sleeve, and the slotted groove has been seted up to the tip of screw rod, when needing adjusting screw rod, drives the screw rod with the screwdriver and rotates.

In this embodiment, the pressure spring 10 forms an elastic member for applying an acting force to the locking member toward the inner rotating member, and in other embodiments, the elastic member may be made of rubber or the like.

In the above embodiments, the sleeve is of a structure with two open ends, in other embodiments, the sleeve may be only open at the inner end, during specific assembly, the elastic member and the locking member are put into the sleeve from the inner end opening, and when the locking member is a locking rod, the locking rod is inserted into the elastic member to prevent the locking rod from being disengaged; when the locking piece is the lock ball, the lock ball and the elastic piece are fixedly connected together, for example, the lock ball is prevented from being separated by gluing and the like. At this time, the value of the set drilling torque is not adjustable.

In this embodiment, one end of the inner rotating member is located in the outer cylinder, and in other embodiments, both ends may be located in the outer cylinder.

In this embodiment, the outer cylinder is connected to a rotary power source, and the inner rotary member is connected to the cutter.

In this embodiment, the number of the grooves is six, and the number of the sleeves is three, in other embodiments, the number of the grooves may be only three, and the grooves are uniformly distributed along the circumferential direction. In other embodiments, the number of grooves and sleeves can be increased according to actual conditions, however, the number of grooves cannot be less than that of sleeves, and no matter whether the grooves or the sleeves are three, the number of grooves and the number of sleeves cannot be less than that of sleeves. In addition, need to explain, similar following condition is also in the utility model discloses an within the protection scope to three sleeve and four recesses are the example, wherein three recess circumference equipartition and with sleeve one-to-one, another recess can arrange wantonly.

The above description is only for the preferred embodiment of the present invention, and the present invention is not limited thereto, the protection scope of the present invention is defined by the claims, and all structural changes equivalent to the contents of the description and drawings of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a drilling is with moment of torsion overload protection device which characterized in that: the method comprises the following steps:

an outer cylinder;

2. The drilling torque overload protection device of claim 1, wherein: the overload protection device further includes:

and the thread adjusting piece is screwed in each sleeve, pushes the corresponding elastic piece inwards, and can change the set drilling torque range by rotating the thread adjusting piece.

3. The drilling torque overload protection device of claim 2, wherein: the thread adjusting piece is an adjusting screw, and the head of the adjusting screw is located outside the sleeve.

4. The drilling torque overload protection device of claim 1, wherein: the wall of the outer barrel is provided with radial through holes, the sleeves penetrate into the corresponding radial through holes, the overload protection device further comprises a gland which enables the inner ends of the sleeves to be pressed in the annular grooves, and the gland is fixedly arranged on the outer barrel.

5. The drilling torque overload protection device according to any one of claims 1 to 4, wherein: the annular groove is trapezoidal with a small inner part and a large outer part, and the inner end of the sleeve is a conical end matched with the shape of the annular groove.

6. The drilling torque overload protection device according to any one of claims 1 to 4, wherein: the outer cylinder is provided with a main shaft in a non-rotating mode, one end of the main shaft is used for being connected with the rotary power source, the other end of the main shaft penetrates into the inner rotating piece, and the inner rotating piece is connected with the corresponding end of the main shaft in a relatively rotating mode through a bearing.

7. The drilling torque overload protection device of claim 6, wherein: the main shaft is provided with a positioning shaft shoulder positioned in the outer cylinder, and the positioning shaft shoulder is in axial stop fit with an inner ring of the bearing; and a bearing end cover is fixed at the end part of the lower end of the main shaft through a hexagon bolt, and the bearing end cover is provided with an annular stop tip matched with the outer ring at the other end of the bearing in a stop way.

8. The drilling torque overload protection device of claim 6, wherein: the torque overload protection device comprises a positioning rod piece, the positioning rod piece is arranged on the outer barrel and extends along the axial direction of the outer barrel, the end part of the positioning rod is used for being matched with the inner rotating piece in a blocking mode, and the axial position of the inner rotating piece is limited, so that the annular groove in the inner rotating piece and the locking piece in the outer barrel are arranged at the same axial position.

9. The drilling torque overload protection device of claim 8, wherein: the outer barrel is provided with a positioning threaded hole, and the positioning rod piece is a threaded piece which is screwed in the positioning threaded hole.

10. The drilling torque overload protection device according to any one of claims 1 to 4, wherein: the locking piece is a lock ball, and the groove is a hemispherical groove matched with the spherical shape of the lock ball.