CN111411888A

CN111411888A - Torque increasing device, power head and rotary drilling rig

Info

Publication number: CN111411888A
Application number: CN202010345065.5A
Authority: CN
Inventors: 黄秋铖; 王龙刚; 嵇詹
Original assignee: Beijing Sany Intelligent Technology Co Ltd
Current assignee: Beijing Sany Intelligent Technology Co Ltd
Priority date: 2020-04-27
Filing date: 2020-04-27
Publication date: 2020-07-14

Abstract

The invention provides a torque increasing device, a power head and a rotary drilling rig, and relates to the field of engineering machinery. The torque increasing device is installed on the power head body and used in the rotary drilling rig, the second torque meets the torque required by the lower pile casing, meanwhile, the acting force of the first torque and the second torque on the mast and the amplitude of the mast is offset, the torque received by the mast and the amplitude-variable hinge point is reduced, and the overall stability and the safety of the rotary drilling rig are improved.

Description

Torque increasing device, power head and rotary drilling rig

Technical Field

The invention relates to the field of engineering machinery, in particular to a torque increasing device, a power head and a rotary drilling rig.

Background

The rotary drilling rig is a construction machine suitable for hole forming operation in building foundation engineering, is widely applied to foundation construction engineering such as municipal construction, highway bridges, high-rise buildings and the like, is matched with different drilling tools, is suitable for hole forming operation of dry (short spiral), wet (rotary bucket) and rock strata, and has the characteristics of high power, large output torque, large axial pressure, flexibility, high construction efficiency, multiple functions and the like.

The rotary drilling rig needs to lower the pile casing to work before pile hole construction, and the pile casing is reasonably pre-buried according to different geological conditions. If the drilling is carried out on land, the pile casing is buried by adopting a pit digging method. Long pile casings or full pile casings are needed to be used in the silty clay which is easy to shrink, the loose miscellaneous fill stratum and the sand layer of the broken hole and the serious permeable stratum. At the moment, the protective cylinder can be cut into the soil by utilizing the forward and reverse rotation rubbing of the power head and the pressurization of the pressure increasing equipment, so that the time for digging a pit and embedding the protective cylinder is shortened. In actual operation, however, the method not only increases the torque required for lowering the casing, but also increases the torque applied to the mast and the luffing hinge point.

Disclosure of Invention

In order to solve the technical problem, the invention provides a torque increasing device which adopts a reverse speed-reducing torque increasing mode to provide the torque required by the lower pile casing and reduce the torque borne by a mast and a variable amplitude hinge point.

The invention also provides a power head which is provided with the torque increasing device and adopts a reverse rotation speed reduction and torque increasing mode to solve the technical problem.

The invention also provides a rotary drilling rig which is provided with the power head, provides the torque required by the lower protective cylinder, reduces the torque borne by the mast and the variable amplitude hinge point, and improves the stability of the whole machine.

In order to achieve the purpose, the torque increasing device provided by the invention is applied to a rotary drilling rig, wherein the torque increasing device comprises a shell frame and a speed reducing mechanism; the speed reduction mechanism is provided in the housing frame, the speed reduction mechanism including:

the first power shaft is of a hollow structure, first transmission teeth are arranged on the outer wall of the first power shaft, and the first power shaft is rotatably mounted on the shell frame;

the second power shaft is of a hollow structure, second transmission teeth are arranged on the inner wall of the second power shaft, the second power shaft is rotatably installed in the shell frame and is coaxial with the first power shaft, and an accommodating cavity is formed between the first transmission teeth and the second transmission teeth; and

the middle transmission assembly comprises a plurality of transmission gears, the transmission gears are arranged in the accommodating cavity and are respectively rotatably installed on the shell frame, the transmission gears are externally meshed with the first transmission teeth, and the transmission gears are internally meshed with the second transmission teeth.

Preferably, the intermediate transmission assembly further comprises a gear carrier fixedly mounted on the shell frame, and the transmission gear is rotatably mounted in the gear carrier.

Furthermore, two ends of the transmission gear are respectively provided with a rotating shaft, and the rotating shafts are rotatably assembled in the gear rack through bearings; the transmission gear is assembled through the bearing, so that the friction resistance is reduced, and the transmission efficiency is improved.

Preferably, the upper end and/or the lower end of the second power shaft is/are rotatably mounted with the shell frame through a rotary support piece; the rotary support piece is arranged to provide required rotary motion for the second power shaft piece and bear axial force, radial force and the like of the second power shaft.

Preferably, the first transmission gear, the second transmission gear and the transmission gear are straight gears or helical gears, and the transmission gear is respectively meshed with the first transmission gear and the second transmission gear.

Preferably, an input connecting piece is installed at one end, far away from the shell frame, of the first power shaft, and the input connecting piece is connected with the input end; the input connecting piece is used for being connected with a power head on the rotary drilling rig.

Preferably, an output connecting piece is mounted at the lower end of the second power shaft, the output connecting piece extends outside the shell frame in the direction far away from the second power shaft, and the output connecting piece is rotatably assembled with the shell frame; the output connecting piece is used for connecting the casing to output large torque.

Further, the output connecting piece is an annular piece with a hollow structure, and the inner diameter of the output connecting piece is larger than or equal to that of the first power shaft; so as to ensure that the drill rod smoothly passes through the output connecting piece and the first power shaft.

The power head comprises a power head body, and any one of the torque increasing devices is mounted on the power head body.

The invention further provides a rotary drilling rig, which comprises a rotary drilling rig body, wherein the power head is installed on the rotary drilling rig body.

The invention has the beneficial effects that:

the invention provides a torque increasing device, wherein a speed reducing mechanism is arranged in a shell frame, the speed reducing mechanism comprises a first power shaft, a second power shaft and an intermediate transmission assembly, the intermediate transmission assembly comprises a plurality of transmission gears, the first power shaft and the second power shaft are coaxially arranged, the transmission gears are arranged in a containing cavity between the first power shaft and the second power shaft, the transmission gears and first transmission teeth are in one-stage external meshing, the transmission gears and second transmission teeth are in one-stage internal meshing, a power head inputs first torque to the first power shaft, speed reduction and torque increase are carried out through the one-stage external meshing and the one-stage internal meshing of the transmission gears to obtain reverse second torque, the second torque is output by the second power shaft and meets torque required by a lower protective cylinder, and simultaneously, the second torque is opposite to the first torque in direction, so that the acting forces of the first torque and the second torque on the mast and the luffing are counteracted, and the torque applied to the mast and the luffing hinge point is reduced.

According to the power head provided by the invention, the torque increasing device is arranged on the power head body, so that the power head outputs a second reverse torque to meet the torque required by the lower pile casing, meanwhile, the acting force of the power head on the mast and the amplitude of the mast is reduced, and the torque applied to the mast and the amplitude-variable hinge point is reduced.

According to the rotary drilling rig provided by the invention, the power head is arranged on the rotary drilling rig to provide required torque for the lower protective cylinder, meanwhile, the acting force of the power head on the mast and the amplitude of the mast is reduced, and the torque applied to the mast and the amplitude-variable hinge point is reduced, so that the overall stability and safety of the rotary drilling rig are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram illustrating a torque increasing device provided in the present application;

FIG. 2 shows a top view of the torque multiplier of FIG. 1 of the present application;

FIG. 3 shows a cross-sectional view taken along line A-A of FIG. 2 of the present application;

FIG. 4 is a partial enlarged view of FIG. 3B of the present application;

fig. 5 shows a schematic mounting diagram of the torque increasing device provided by the application.

Description of the main element symbols:

1-a first power shaft; 2-a housing frame; 3-a second power shaft; 4-an intermediate transmission assembly; 10-an input connection; 11-an input shaft member; 11 a-input terminal; 11 b-a first drive end; 12-a third bearing; 20-upper end cover; 20 a-a first via; 21-lower end cap; 21 a-a second via; 22-annular side wall; 23-a cassette; 30-an output shaft; 30 a-a second drive end; 30 b-an output; 31-an output connection; 32-a first bearing; 33-a slewing support; 40-a transmission gear; 40 a-external engagement; 40 b-inner meshing; the 41-gear carrier; 42-a second bearing; 43-a rotating shaft; 100-torque increasing device; 200-a power head; 300-mast; 400-protecting the cylinder.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Example one

Referring to fig. 1, fig. 2 and fig. 5, the torque increasing device 100 provided in this embodiment is applied to a rotary drilling rig, and the torque increasing device 100 includes: a housing frame 2 and a speed reducing mechanism. The casing frame 2 is arranged into a cylindrical casing frame 2, the casing frame 2 is provided with an upper end cover 20, a lower end cover 21 and an annular side wall 22 for connecting the upper end cover 20 and the lower end cover 21, the annular side wall 22 extends towards one direction to form a clamping seat 23 for sliding installation, the clamping seat 23 is assembled with a mast 300 in a rotary drilling rig in a sliding mode, the casing frame 2 is made to slide up and down on the mast 300 along with the power head 200, the speed reducing mechanism is arranged in the casing frame 2, the speed reducing mechanism achieves speed reduction and torque increase, and outputs a reverse large torque.

Referring again to fig. 3, the reduction mechanism includes: the power transmission device comprises a first power shaft 1, a second power shaft 3 and an intermediate transmission assembly 4 arranged between the first power shaft 1 and the second power shaft 3. The first power shaft 1 inputs a first torque and transmits the first torque to the second power shaft 3 through the intermediate transmission assembly 4, the second power shaft 3 outputs a second torque in the direction of the first torque, and the second torque is larger than the first torque so as to meet the torque required by the rotary drilling rig when the protective cylinder 400 is arranged below, the working efficiency is improved, the burying and tamping performance of the protective cylinder 400 is shortened, the pit digging and burying time is shortened, and the hole forming efficiency is improved.

Specifically, the first power shaft 1 is arranged in the housing frame 2, the first power shaft 1 includes an input shaft 11 and an input connecting member 10, the input shaft 11 is hollow and is arranged to ensure that a drill rod can smoothly pass through the hollow. The input shaft member 11 is rotatably mounted in the housing frame 2.

Referring to fig. 3 and 4, the input shaft 11 includes: input 11a and relative first transmission end 11b, first transmission end 11b is located in casing frame 2, be equipped with first transmission tooth on the outer wall of transmission end, input 11a to casing frame 2 extends outward, that is to upper end cover 20 extends outside casing frame 2. Meanwhile, the upper end cap 20 is provided with a first through hole 20a, and the input end 11a is accommodated in the first through hole 20 a.

The input connecting piece 10 is also of a hollow structure, and the purpose of the input connecting piece is to enable a drill rod to smoothly pass through the hollow structure, the input connecting piece 10 is installed at the input end 11a, the input connecting piece 10 is used for being connected with a power head 200 on the rotary drilling rig, and the input connecting piece 10 is used for transmitting torque output by the power head 200 to the output shaft piece 30.

In some specific embodiments, the first transmission teeth and the first transmission end 11b are provided as separate parts, and the first transmission teeth are welded or keyed to the first transmission end 11 b.

In this embodiment, the first transmission teeth and the first transmission end 11b are integrally formed, that is, the first transmission teeth are directly formed at the first transmission end 11b, and the power input shaft 11 is a gear shaft.

Referring to fig. 3 and 4, specifically, the second power shaft 3 is disposed in the housing frame 2, and the second power shaft 3 includes: an output shaft 30 and an output connector 31 of hollow structure. The hollow structure of the output shaft member 30 is to ensure that the drill rod can smoothly pass through the hollow structure, the output shaft member 30 is rotatably installed in the housing frame 2, and the output shaft member 30 is sleeved on the input shaft member 11 and is coaxially arranged with the input shaft member 11.

In some specific embodiments, the upper end of the input shaft member 11 is rotatably mounted to the housing frame 2 by a rotary support member 33; the arrangement of the slewing bearing 33 provides the required slewing movement of the output shaft 30 while bearing axial, radial, etc. forces of the output shaft 30.

In some specific embodiments, the lower end of the input shaft member 11 is rotatably mounted to the housing frame 2 by a rotary support member 33; the arrangement of the slewing bearing 33 provides the required slewing movement of the output shaft 30 while bearing axial, radial, etc. forces of the output shaft 30.

In some specific embodiments, the upper end and the lower end of the input shaft member 11 are rotatably mounted with the housing frame 2 by a rotary support member 33; the arrangement of the slewing bearing 33 provides the required slewing movement of the output shaft 30 while bearing axial, radial, etc. forces of the output shaft 30.

In an embodiment where a rotary support member 33 is provided at the upper end of the input shaft member 11, the output shaft member 30 includes: second transmission end 30a and output 30b, be equipped with the second driving tooth on the inner wall of second transmission end 30a, just first driving tooth corresponds the second driving tooth sets up, first driving tooth with be formed with between the second driving tooth and hold the chamber (not shown), output 30b is located the output shaft deviates from one side of input 11a, promptly output 30b towards lower end cover 21.

Referring to fig. 3 and 4, the output connector 31 is mounted at the output end 30b, and the output connector 31 extends outside the housing frame 2 in a direction away from the input end 11a, it can be understood that the output connector 31 penetrates through the lower end cover 21, and the lower end cover 21 is provided with a second through hole 21a, and the second through hole 21a accommodates the output connector 31. The output connecting piece 31 is rotatably assembled with the lower end cover 21 through a first bearing 32; the output connector 31 is used for connecting the casing 400 to transmit the second torque.

Further, in this embodiment, the output connector 31 is a ring member having a hollow structure, and the second transmission end 30a is mounted in the output connector 31 through a third bearing 12. The inner diameter of the output connector 31 is greater than or equal to the inner diameter of the input shaft 11, and in this embodiment, the inner diameter of the output connector 31 is greater than the inner diameter of the input shaft 11, so as to ensure that a drill rod can smoothly pass through the output connector 31 and the input shaft.

In particular embodiments, the second drive teeth and the second drive end 30a are separate pieces, and the second drive teeth are welded or keyed to an inner wall of the second drive end 30 a.

In this embodiment, the second transmission gear and the second transmission end 30a are integrally formed, that is, the second transmission gear is directly formed on the inner wall of the second transmission end 30a by machining, and the power transmission shaft is an inner ring shaft.

Referring to fig. 3 and 4, in particular, the intermediate transmission assembly 4 is disposed between the input shaft member 11 and the output shaft member 30. The intermediate transmission assembly 4 comprises: the transmission gears 40 are arranged in the accommodating cavities (not shown) and are rotatably mounted on the shell frame 2, the transmission gears 40 are respectively meshed with the first transmission gear and the second transmission gear, the first transmission gear drives the second transmission gear to reversely decelerate and rotate through the transmission gears 40, it can be understood that the transmission gears 40 and the first transmission gear are in one-stage external meshing 40a, the transmission gears 40 and the second transmission gear are in one-stage internal meshing 40b, and after transmission is carried out through the one-stage external meshing 40a and the one-stage internal meshing 40b, the second transmission gear and the first transmission gear are reversely rotated, speed reduction and torque increase are realized, and therefore, the output connecting piece 31 outputs the second torque.

The number of the transmission gears 40 can be three, four, five or six, and the like, as long as the axes of the transmission gears 40 can be arranged on a virtual circle in a surrounding manner and do not interfere with each other. The specific selection needs to be considered comprehensively according to the output torque and the size of the casing 400, and the embodiment is only for illustration and is not used for limiting the protection scope.

In this embodiment, the intermediate transmission assembly 4 further includes a plurality of gear carriers 41, the number of the gear carriers 41 is equal to the number of the transmission gears 40, each of the transmission gears 40 is installed in the corresponding gear carrier 41, one end of the gear carrier 41 is fixedly installed on the upper end cover 20 of the housing frame 2, and the other end is also placed in the accommodating cavity (not shown).

In some specific embodiments, the transmission gear 40 is designed as an integral gear shaft structure, and two ends of the transmission gear 40 extend with rotating shafts 43 respectively, and the rotating shafts 43 are assembled in the gear frame 41 through second bearings 42 respectively.

In some specific embodiments, the transmission gear 40 is designed in a structure in which a gear and a rotating shaft 43 are assembled by a key, and the rotating shaft 43 extends at both ends of the transmission gear 40 and is respectively fitted in the gear holder 41 through a second bearing 42.

In an embodiment where the transmission gear 40 is designed as an integral gear shaft structure, the first transmission gear, the second transmission gear and the transmission gear 40 are provided as straight teeth, and the transmission gear 40 is respectively engaged with the first transmission gear and the second transmission gear.

In some embodiments, the first gear teeth, the second gear teeth, and the drive gear 40 are helical teeth.

Referring to fig. 1 to 5, the torque increasing device 100 according to this embodiment is implemented such that the power head 200 inputs a first torque to the input shaft 11, and the first transmission gear is engaged with the first-stage external gear 40a of the transmission gear 40, and the transmission gear 40 is engaged with the first-stage internal gear 40b of the second transmission gear, so as to reduce the speed and increase the torque, and the rotation direction of the second transmission gear is opposite to the rotation direction of the first transmission gear, so that the output connection member 31 outputs a second torque after increasing the torque. The second torque satisfies the torque required by the lower casing 400, and at the same time, the second torque is opposite to the first torque in direction, so that the acting forces of the first torque and the second torque on the mast 300 and the luffing jib are offset, and the torque applied to the mast 300 and the luffing jib hinge point is reduced.

Further, the second torque output by the torque increasing device 100 provided by the embodiment is greater than the first torque output originally, so that the installation of the casing 400 with a larger size and a deeper depth can be met when the torque increasing device is assembled on the power head 200 for use, and most engineering requirements are met. And extra equipment such as a full-slewing drilling machine, a pipe rolling machine or a crawler crane is not required to be added for full casing construction, so that the equipment cost investment is reduced, and the labor intensity of workers is reduced. The disassembly and assembly of the embodiment are simple, the construction efficiency is greatly improved, the operation environment is improved, the cost input is saved, and the economic benefit is good.

Example two

Referring to fig. 3 and fig. 4, the torque increasing device 100 provided in the present embodiment is an improvement on the basis of the first embodiment, and the main improvement point is that the gear rack 41 is provided, and other structural schemes are not changed, and the first embodiment is still used. The following describes the improvement in detail.

Specifically, the method comprises the following steps: in this embodiment, the intermediate transmission assembly 4 further includes a gear rack 41, the gear rack 41 is configured as a single body, that is, as an integral structure, each of the transmission gears 40 is rotatably installed in the gear rack 41, one end of the gear rack 41 is fixedly installed on the upper end cover 20 of the shell frame 2, and the other end is also placed in the accommodating cavity (not shown).

The torque increasing device 100 provided in this embodiment is the same as the first embodiment, and will not be described in detail herein.

EXAMPLE III

Referring to fig. 1 to 5, the present embodiment provides a power head 200 applied to a rotary drilling rig, where the power head 200 includes a power head body, and the torque increasing device 100 provided in the first embodiment or the second embodiment is installed on the power head body.

The power head 200 outputs a first torque, and outputs a second torque in an opposite direction after the torque increasing device 100 decelerates and increases the torque, wherein the second torque meets the torque required by the lower casing 400, and meanwhile, the acting force of the first torque and the second torque on the mast 300 and the amplitude of the.

The second torque output by the power head 200 provided by the embodiment is larger than the originally output first torque, so that the installation of the casing 400 with larger size and deeper depth can be met, and most engineering requirements are met. And extra equipment such as a full-slewing drilling machine, a pipe rolling machine or a crawler crane is not required to be added for full casing construction, so that the equipment cost investment is reduced, and the labor intensity of workers is reduced. The disassembly and assembly of the embodiment are simple, the construction efficiency is greatly improved, the operation environment is improved, the cost input is saved, and the economic benefit is good.

Example four

Referring to fig. 1 to 5, the embodiment provides a rotary drilling rig, which includes a rotary drilling rig body, the rotary drilling rig body is connected with a mast 300 through a luffing mechanism, the power head 200 provided in the third embodiment is mounted on the mast 300, a second torque is output through the power head 200 to provide a required torque for a lower protective cylinder 400, meanwhile, an acting force of the power head 200 on the mast 300 and the luffing is reduced, and a torque received by a hinge point of the mast 300 and the luffing is reduced, so that overall stability and safety of the rotary drilling rig are improved.

According to the rotary drilling rig provided by the embodiment, the second torque output after the power head 200 is installed is larger, so that the installation of the casing 400 with a larger size and a deeper depth can be met, and most engineering requirements are met. And extra equipment such as a full-slewing drilling machine, a pipe rolling machine or a crawler crane is not required to be added for full casing construction, so that the equipment cost investment is reduced, and the labor intensity of workers is reduced. The disassembly and assembly of the embodiment are simple, the construction efficiency is greatly improved, the operation environment is improved, the cost input is saved, and the economic benefit is good.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. The torque increasing device is applied to a rotary drilling rig and is characterized by comprising a shell frame and a speed reducing mechanism; the speed reduction mechanism is provided in the housing frame, the speed reduction mechanism including:

2. The torque increasing device according to claim 1, wherein the intermediate transmission assembly further comprises a gear carrier fixedly mounted on the housing frame, the transmission gear being rotatably mounted in the gear carrier.

3. The torque increasing device according to claim 2, wherein rotating shafts are provided at both ends of the transmission gear, respectively, and the rotating shafts are rotatably fitted in the gear frame through bearings.

4. The torque increasing device according to claim 1, wherein the upper end and/or the lower end of the second power shaft is rotatably mounted with the housing frame by means of a swivel support.

5. The torque increasing device according to claim 1, wherein the first transmission gear, the second transmission gear, and the transmission gear are provided as straight teeth or helical teeth, and the transmission gear is engaged with the first transmission gear and the second transmission gear, respectively.

6. The torque increasing device according to any one of claims 1 to 5, wherein an input connector is mounted to an end of the first power shaft remote from the housing frame.

7. The torque increasing device according to any one of claims 1 to 5, wherein an output connecting member is mounted to a lower end of the second power shaft, the output connecting member extending outside the housing frame in a direction away from the second power shaft, and the output connecting member is rotatably fitted to the housing frame.

8. The torque increasing device according to claim 7, wherein the output connecting member is an annular member of a hollow structure, and an inner diameter of the output connecting member is greater than or equal to an inner diameter of the first power shaft.

9. A power head applied to a rotary drilling rig is characterized by comprising a power head body, wherein the power head body is provided with a torque increasing device according to any one of claims 1-8.

10. A rotary drilling rig is characterized by comprising a rotary drilling rig body, wherein the power head of claim 9 is installed on the rotary drilling rig body.