Swivel head for down-the-hole drill

Abstract

The utility model relates to a swiveling head for a down-the-hole drill. The swiveling head comprises an input gear shaft, an output gear, a main shaft and a gear box. The input gear shaft is connected to the power system which is used for driving the input gear shaft to rotate. The output gear is meshed with the input gear shaft; the output gear is sleeved on the main shaft; the output gear is used for driving the spindle to rotate; the central shaft of the input gear shaft is parallel to the central shafts of the output gear and the main shaft; the gear box provides mounting space for the input gear shaft and the output gear; the input gear shaft and the main shaft are rotationally connected with the gearbox; the gearbox is provided with a third through hole used for disassembling the input gear shaft. Through the pair of input gear shafts, the torque of the output gear is increased, and the service life of the input gear shafts is prolonged; through reasonable layout of the input gear shaft and the output gear, gears of the gear box are effectively reduced, and the gear box is lighter.

Description

Technical Field

[0001] The utility model relates to the technical field of engineering machinery, in particular to a rotary head used for a down-the-hole drill. Background Art

[0002] Down-the-hole drill is a construction machine used for drilling blasting holes in open-pit mining operations. It is mainly composed of a traveling mechanism, a frame, a power system, a slewing head, a boom mechanism, a dust removal mechanism and an electronic control system. The slewing head is fixed on the boom mechanism, and its movement can provide the rotational power required for drilling to achieve drilling operations.

[0003] The commonly used components of the slewing head on the market mainly include reduction gearbox, drive motor, mounting base plate and other parts. The slewing head is fixed on the propulsion beam slide through the mounting base plate. The input shaft of the slewing head is connected to the hydraulic motor, which drives the input shaft to rotate and is transmitted to the output shaft through the meshing transmission of the reduction gearbox inside the slewing head. The high-speed and low-torque input of the motor is converted into low-speed and high-torque output through the reduction gearbox. As an important part of the slewing head device, the output speed and output torque of the gearbox have a decisive effect on the drilling ability of the drilling rig. The contact strength, bending strength, theoretical calculated life of the bearings and the use conditions of the seals will affect the service life of the gearbox. Therefore, if the gearbox is designed to meet the requirements according to the existing structural form of the slewing head, the size of the gearbox will increase and the weight will increase.

[0004] Authorization announcement number: CN 209586255 U, application date: 2019.02.15, utility model name is a rotary power head for a down-the-hole drill, this utility model discloses a rotary power head for a down-the-hole drill, including a gear box, a front cover, a rear cover and a power output shaft, the front cover and the rear cover are respectively fixed to the front and rear ends of the gear box, and also include a sleeve; the rear cover is provided with a first countersunk hole, the rear end of the power output shaft is provided with a second countersunk hole, the rear end of the sleeve is placed in the first countersunk hole, the front end is placed in the second countersunk hole, and a gray ring is installed between the sleeve and the rear cover, and between the sleeve and the power output shaft; the front cover is provided with a center hole, the front end of the power output shaft passes through the center hole of the front cover, and the power output shaft is connected to the gear box through a pair of bearings. The rotary power head for a down-the-hole drill adopts the utility model, the gas seal can be easily replaced, and the service life of the gas seal and the power output shaft are extended.

[0005] According to the description of the prior art, a large gear and a small gear are provided in the gearbox, the large gear is fixedly mounted on the power output shaft, the small gear meshes with the large gear, the motor drives the small gear to rotate (a motor is installed on each side of the small gear), thereby driving the large gear to rotate, and the large gear then drives the power output shaft to rotate synchronously to output power. From the above text, it can be concluded that the small gear is the input shaft, and there is only one input shaft. The disadvantages are obvious. The torque of the large gear and the output shaft is not large, which is difficult to meet the requirements of high-intensity impact working conditions, and the service life of the small gear is not long.

[0006] In addition, the cover of the gear box is located above the box body. Even if the cover is opened, it is difficult to remove the internal parts for repair or replacement. Utility Model Content

[0007] In view of the defects in the prior art such as small output shaft torque, difficulty in meeting the requirements of impact working conditions of down-the-hole drills, limited service life of pinions, and difficulty in disassembly and maintenance of parts, the purpose of the utility model is to provide a swivel head for down-the-hole drills.

[0008] The technical solution provided by the utility model is:

[0009] A rotary head for a down-the-hole drill, comprising:

[0010] An input gear shaft, the input gear shaft is connected to a power system, and the power system is used to drive the input gear shaft to rotate;

[0011] An output gear, the output gear meshing with the input gear shaft;

[0012] The main shaft, the output gear is sleeved on the main shaft; the output gear is used to drive the main shaft to rotate; the central axis of the input gear shaft is parallel to the central axis of the output gear and the main shaft;

[0013] The gear box provides installation space for the input gear shaft and the output gear; the input gear shaft and the main shaft are rotationally connected to the gear box; the gear box is provided with a third through hole for disassembling the input gear shaft.

[0014] Furthermore, there is a pair of input gear shafts, each of which is connected to a power system; and the input gear shafts are arranged on one side of the output gear.

[0015] Furthermore, on a cross section perpendicular to the central axis of the main shaft, the intersection of the central axis of the input gear shaft and the cross section is A, the intersection of the central axis of the output gear and the cross section is B, and the intersection of the central axis of the main shaft and the cross section is C; the angle formed by AC and BC is not greater than 60 degrees.

[0016] Furthermore, the gear box includes a side plate and a box body; the side plate is provided with a first through hole, and the box body is provided with a second through hole opposite to the first through hole; the main shaft passes through the first through hole and the second through hole in sequence.

[0017] Furthermore, the main shaft is connected to the output gear through a clamping sleeve; a first bearing and a second bearing are provided at both ends of the main shaft; the outer ring of the first bearing is installed in the first through hole, the outer ring of the second bearing is installed in the second through hole, and the first bearing and the second bearing are located on both sides of the output gear; the main shaft is rotatably connected to the gear box through the first bearing and the second bearing.

[0018] Furthermore, one end of the main shaft close to the second bearing is used to connect to the drill rod; the axial clearance of the second bearing is greater than the axial clearance of the first bearing.

[0019] Furthermore, a first transparent cover is connected to the outer side of the first through hole via a fastener, and a second transparent cover is connected to the outer side of the second through hole via a fastener; the first transparent cover and the second transparent cover are provided with through holes for the main shaft to pass through; the first transparent cover is used to limit the first bearing, and the second transparent cover is used to limit the second bearing and support the main shaft at the same time.

[0020] Furthermore, the second bearing is limited by a distance ring, and the distance ring includes a first distance ring and a second distance ring respectively located at both ends of the second bearing; one end of the first distance ring abuts against the output gear, and the other end abuts against one end of the second bearing, and one end of the second distance ring abuts against the second bearing, and the other end abuts against the second transparent cover.

[0021] Furthermore, the housing is provided with a first groove, and the side panel is provided with a fourth through-hole opposite to the first groove; a third bearing and a fourth bearing are respectively provided at both ends of the input gear shaft; the outer ring of the third bearing is adapted to the first groove of the housing, and the outer ring of the fourth bearing is installed in the fourth through-hole; the input gear shaft is rotatably connected to the gear box through the third bearing and the fourth bearing.

[0022] Furthermore, the fourth through hole is provided with a second groove matched with a shaft retaining ring; the shaft retaining ring is used to limit the fourth bearing.

[0023] Furthermore, the third through hole is arranged on the box body, and the box body and the cover plate are detachably connected; the third through hole corresponds to the center position of the cover plate.

[0024] Compared with the prior art, the technical solution provided by the utility model has the following beneficial effects:

[0025] The utility model designs a pair of input gear shafts, which not only increases the torque of the output gear, so that the slewing head can simultaneously meet the requirements of high-intensity impact working conditions, but also increases the life of the input gear shaft; through the reasonable layout of the input gear shaft and the output gear, the gears of the gear box are effectively reduced, making the gear box lighter; the gear box is provided with a third through hole, which is specially used for disassembling the input gear shaft. During the normal use of the slewing head, the third through hole is covered by the cover plate.

[0026] In addition, the gear box can be disassembled from the side, which facilitates the disassembly and installation of the expansion sleeve and other parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the overall structure of a rotary head for a down-the-hole drill after installation in one embodiment of the present application;

[0028] Figure 2 This is a schematic diagram of the disassembled structure of a rotary head gearbox for a down-the-hole drill in one embodiment of the present application;

[0029] Figure 3 This is a schematic diagram of the overall structure of the input gear shaft and the output gear in one embodiment of the present application;

[0030] Figure 4 This is a schematic diagram of the overall structure of the input gear shaft and the output gear at another angle in one embodiment of the present application;

[0031] Figure 5 A cross-sectional view of a rotary head for a down-the-hole drill in one embodiment of the present application;

[0032] Figure 6 Another cross-sectional view of a rotary head for a down-the-hole drill in one embodiment of the present application;

[0033] Figure 7 This is a schematic diagram of the main shaft structure in one embodiment of the present application;

[0034] Figure 8 This is a schematic diagram of the overall structure of the input gear shaft in one embodiment of the present application;

[0035] Fig. 9 This is a schematic diagram of a cross-section of an input gear shaft in one embodiment of the present application;

[0036] Fig.10 This is a schematic diagram of the distance ring structure in one embodiment of the present application.

[0037] Explanation of the symbols in the schematic diagram:

[0038] Input gear shaft 1, third bearing 11, fourth bearing 12, shaft retaining ring 121, internal spline 13;

[0039] Output gear 2;

[0040] Main shaft 3, first bearing 31, second bearing 32, first distance ring 321, second distance ring 322;

[0041] A first transparent cover 4;

[0042] The second transparent cover 5;

[0043] Gear box 6, first through hole 61, second through hole 62, third through hole 63, fourth through hole 64, side plate 65, box body 66, sealing gasket 67, cover plate 68;

[0044] Expansion sleeve 7;

[0045] Powertrain 8. DETAILED DESCRIPTION

[0046] In order to further understand the content of the utility model, the utility model is described in detail in conjunction with the drawings and embodiments.

[0047] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of implementation. The change or adjustment of their relative relationship should also be regarded as the scope of implementation of the present invention without substantially changing the technical content.

[0048] The present application discloses a rotary head for a down-the-hole drill, comprising a gear box 6 that plays a major supporting role, the gear box 6 providing installation space for an input gear shaft 1 and an output gear 2, the gear box 6 comprising a side plate 65, a box body 66 and a sealing gasket 67 that plays a sealing role, the sealing gasket 67 being arranged between the side plate 65 and the box body 66. By separating the side plate 65 from the box body 66, parts can be easily repaired or replaced, and the operability is strong.

[0049] The side plate 65 is provided with a first through hole 61 and a fourth through hole 64, and the side of the box body 66 is provided with a first groove and a second through hole 62. The first through hole 61 and the second through hole 62 are arranged opposite to each other so that the main shaft 3 can pass through; the fourth through hole 64 and the first groove are arranged opposite to each other, and the fourth through hole 64 is located obliquely above the first through hole 61. The fourth through hole 64 and the first groove are respectively used to locate the two ends of the input gear shaft 1. There is a pair of input gear shafts 1, so two fourth through holes 64 and two first grooves are provided.

[0050] A pair of bearings are arranged at both ends of each input gear shaft 1, namely, a third bearing 11 and a fourth bearing 12. The outer ring of the third bearing 11 is matched with the first groove on the side of the housing 66, and the outer ring of the fourth bearing 12 is installed in the fourth through hole 64 on the side plate 65. The third bearing 11 and the fourth bearing 12 are used to position and support the input gear shaft 1, and at the same time, the rotation connection between the input gear shaft 1 and the gear box 6 is realized.

[0051] The input gear shaft 1 is provided with an internal spline 13, and the power system 8 is provided with an external spline. The internal and external splines cooperate to complete the connection between the input gear shaft 1 and the power system 8. Each input gear shaft 1 is connected to a power system 8, and the power system 8 is preferably a hydraulic motor. After the input gear shaft 1 and the power system 8 are connected, the fourth bearing 12 is subjected to force and may produce a slight movement. The technical solution also provides a shaft retaining ring 121 for further limiting the fourth bearing 12. The shaft retaining ring 121 is installed in the second groove of the fourth through hole 64.

[0052] The shaft retaining ring 121 is preferably an elastic component. When the shaft retaining ring 121 is not installed, its size is slightly larger than the second groove in the fourth through hole 64. After appropriate compression, it can be tightly fixed in the second groove.

[0053] In order to improve the torque of the output gear 2 and increase the service life of the input gear shaft 1, the present application designs two input gear shafts 1. The technical solution of the present application can improve the torque of the output gear 2 and increase the service life of the input gear shaft 1 for the following reasons: if only one input gear shaft is designed, and the two ends of the input gear shaft are connected to a power system (in order to simulate the solution of two input gear shafts 1 in the present application, each input gear shaft 1 is connected to a power system 8), then the limit load on the meshing point of the input gear shaft and the output gear is marked as F, and the torque of the output gear is marked as T. When the gear pitch circle radius of the input gear shaft and the gear pitch circle radius of the output gear are the same as those of the present application, by designing two input gear shafts 1, each meshing point of the input gear shaft 1 and the output gear 2 only needs to bear a load of F / 2, and the torque of the output gear 2 can reach T. As long as the load at the meshing point of the input gear shaft 1 and the output gear 2 is greater than F / 2, the torque of the output gear 2 can be greater than T. Therefore, the torque of the output gear 2 can be increased by designing two input gear shafts 1.

[0054] If only one input gear shaft is designed, the gear transmission may fail under repeated loading due to the large load at the meshing point, and the input gear shaft may have broken teeth, tooth surface wear, and tooth surface pitting, etc., so the service life of the input gear shaft is short. The present application increases the number of input gear shafts 1 and reduces the size of the gear box 6 while increasing the service life of the input gear shaft 1 through reasonable layout design, thereby making the gear box lightweight.

[0055] In the present application, two input gear shafts 1 are meshed with the output gear 2, and the input gear shafts 1 are both located on the same side of the output gear 2, specifically, both are located obliquely above the output gear 2. In order to reduce the size of the gearbox 6, on the cross section perpendicular to the central axis of the main shaft 3, the central axis of the input gear shaft 1 and the cross section intersect at A, the central axis of the output gear 2 and the cross section intersect at B, the central axis of the main shaft 3 and the cross section intersect at C, and the angle formed by AC and BC is no greater than 60 degrees. The power system 8 drives the input gear shaft 1 to rotate, and the two input gear shafts 1 drive the output gear 2 to rotate.

[0056] The output gear 2 is interference fit with the main shaft 3 through the expansion sleeve 7. In order to facilitate the disassembly or installation of the expansion sleeve 7, the gear box 6 needs to have a detachable side panel. At the same time, in order to facilitate the disassembly or installation of the input gear shaft 1 and the output gear 2, the gear box 6 is also preferably configured to have a detachable side panel. Therefore, the gear box 6 includes a detachable side panel 65 and a box body 66, and the side panel 65 and the box body 66 are sealed and installed by a sealing gasket 67.

[0057] The central axis of the input gear shaft 1 is parallel to the central axes of the output gear 2 and the main shaft 3. The output gear 2 drives the main shaft 3 to rotate. The main shaft 3 is rotationally connected to the gear box 6 through the first bearing 31 and the second bearing 32. The outer ring of the first bearing 31 is installed in the first through hole 61, and the outer ring of the second bearing is installed in the second through hole 62. The first bearing 31 and the second bearing 32 are respectively located on both sides of the output gear 2.

[0058] A first transparent cover 4 is disposed outside the first through hole 61, and the first transparent cover 4 is connected to the first through hole 61 by a fastener; a second transparent cover 5 is disposed outside the second through hole 62, and the second transparent cover 5 is connected to the second through hole 62 by a fastener. Both the first transparent cover 4 and the second transparent cover 5 are provided with a through hole for the spindle 3 to pass through, the first transparent cover 4 is used to limit the first bearing 4, and the second transparent cover 5 is used to limit the second bearing 32 and support the spindle 3 at the same time.

[0059] In order to further limit the second bearing 32, a distance ring is also provided, which includes a first distance ring 321 and a second distance ring 322; the first distance ring 321 and the second distance ring 322 are respectively located on both sides of the second bearing 32, wherein one end of the first distance ring 321 abuts against the output gear 2, and the other end abuts against the second bearing 32, and one end of the second distance ring 322 abuts against the second bearing 32, and the other end abuts against the second transparent cover 5.

[0060] The axial clearance of the second bearing 32 is greater than the axial clearance of the first bearing 31, and the second bearing 32 is preferably a double-row tapered roller bearing. The end of the main shaft 3 close to the second bearing 32 is connected to the drill rod of the down-the-hole drill, and the main shaft 3 drives the drill rod to rotate, thereby performing a drilling operation. During the drilling operation of the down-the-hole drill, the drill rod is subjected to a large axial force, and this axial force will be transmitted from the drill rod to the main shaft 3, and then from the main shaft 3 to the second bearing 32. Therefore, compared with the first bearing 31, the second bearing 32 can withstand a larger axial force, so the axial clearance of the second bearing 32 is greater than the axial clearance of the first bearing 31.

[0061] The gear box 6 is also provided with a pair of cover plates 68. More specifically, the cover plates 68 are provided on the box body 66 and are connected to the box body 66 by fasteners. When the cover plates 68 are opened, it can be seen that a third through hole 63 is provided on the box body 66, and the third through hole 63 is directly opposite to the center of the cover plate 68. During normal use of the slewing head, the third through hole 63 is plugged with a seal. When the slewing head needs to be repaired, the seal is removed and a disassembly tool is passed through the third through hole 63 to realize the disassembly of the input gear shaft 1.

[0062] The height of the gear box 6 does not exceed 370 mm, the length does not exceed 460 mm, and the length direction is a direction perpendicular to the central axis of the main shaft 3.

[0063] In addition, lifting holes are provided on the top surface of the gear box 6 and the outer circumference of the second through hole 62 to facilitate the lifting and installation of the slewing head.

[0064] The above schematically describes the present invention and its implementation methods, which are not restrictive. The drawings show only one implementation method of the present invention, and the actual structure is not limited thereto. Therefore, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A rotary head for a down-the-hole drill, characterized in that: include: An input gear shaft (1), wherein there is a pair of input gear shafts (1) and both are connected to a power system (8), wherein the power system (8) is used to drive the input gear shaft (1) to rotate; An output gear (2), the output gear (2) meshing with the input gear shaft (1); A main shaft (3), the output gear (2) being sleeved on the main shaft (3); the output gear (2) being used to drive the main shaft (3) to rotate; the central axis of the input gear shaft (1) and the central axes of the output gear (2) and the main shaft (3) being parallel to each other; A gear box (6) is provided, wherein the gear box (6) provides installation space for the input gear shaft (1) and the output gear (2); the input gear shaft (1) and the main shaft (3) are rotationally connected to the gear box (6); and the gear box (6) is provided with a third through hole (63) for disassembling the input gear shaft (1).

2. A rotary head for a down-the-hole drill according to claim 1, characterized in that: The input gear shafts (1) are all arranged on one side of the output gear (2).

3. A rotary head for a down-the-hole drill according to claim 2, characterized in that: On a cross section perpendicular to the central axis of the main shaft (3), the intersection point of the central axis of the input gear shaft (1) and the cross section is A, the intersection point of the central axis of the output gear (2) and the cross section is B, and the intersection point of the central axis of the main shaft (3) and the cross section is C; the angle formed by AC and BC is not greater than 60 degrees.

4. A rotary head for a down-the-hole drill according to claim 1, characterized in that: The gear box (6) comprises a side plate (65) and a box body (66); the side plate (65) is provided with a first through hole (61), and the box body (66) is provided with a second through hole (62) opposite to the first through hole (61); the main shaft (3) passes through the first through hole (61) and the second through hole (62) in sequence.

5. A rotary head for a down-the-hole drill according to claim 4, characterized in that: The main shaft (3) is connected to the output gear (2) through a tightening sleeve (7); a first bearing (31) and a second bearing (32) are provided at both ends of the main shaft (3); the outer ring of the first bearing (31) is installed in a first through hole (61), the outer ring of the second bearing (32) is installed in a second through hole (62), and the first bearing (31) and the second bearing (32) are located on both sides of the output gear (2); the main shaft (3) is rotatably connected to the gear box (6) through the first bearing (31) and the second bearing (32).

6. A rotary head for a down-the-hole drill according to claim 5, characterized in that: One end of the main shaft (3) close to the second bearing (32) is used for connecting a drill rod; the axial clearance of the second bearing (32) is greater than the axial clearance of the first bearing (31).

7. A rotary head for a down-the-hole drill according to claim 5, characterized in that: The first through hole (61) is connected to a first transparent cover (4) via a fastener on the outside thereof, and the second through hole (62) is connected to a second transparent cover (5) via a fastener on the outside thereof; the first transparent cover (4) and the second transparent cover (5) are provided with through holes for the main shaft (3) to pass through; the first transparent cover (4) is used to limit the first bearing (31), and the second transparent cover (5) is used to limit the second bearing (32) and simultaneously support the main shaft (3).

8. A rotary head for a down-the-hole drill according to claim 7, characterized in that: The second bearing (32) is limited by a distance ring, and the distance ring comprises a first distance ring (321) and a second distance ring (322) respectively located at two ends of the second bearing (32); one end of the first distance ring (321) abuts against the output gear (2), and the other end abuts against one end of the second bearing (32); one end of the second distance ring (322) abuts against the second bearing (32), and the other end abuts against the second transparent cover (5).

9. A rotary head for a down-the-hole drill according to claim 4, characterized in that: The housing (66) is further provided with a first groove, and the side plate (65) is provided with a fourth through hole (64) opposite to the first groove; a third bearing (11) and a fourth bearing (12) are respectively provided at both ends of the input gear shaft (1); the outer ring of the third bearing (11) is matched with the first groove of the housing (66), and the outer ring of the fourth bearing (12) is installed in the fourth through hole (64); the input gear shaft (1) is rotatably connected to the gear box (6) through the third bearing (11) and the fourth bearing (12).

10. A rotary head for a down-the-hole drill according to claim 9, characterized in that: The fourth through hole (64) is provided with a second groove matched with a shaft retaining ring (121); the shaft retaining ring (121) is used to limit the fourth bearing (12).

11. The rotary head for a down-the-hole drill according to claim 4, characterized in that: The third through hole (63) is arranged on the box body (66), and the box body (66) and the cover plate (68) are detachably connected; the third through hole (63) corresponds to the center position of the cover plate (68).

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