CN213297817U - Down-the-hole hammer - Google Patents

Abstract

The invention discloses a down-the-hole impactor which comprises an outer sleeve, wherein a first joint, an air inlet non-return reversing mechanism hermetically connected with the first joint, an air cylinder installed in a matching manner with the inner wall of the outer sleeve, a second joint fixedly connected with the lower end of the outer sleeve and a drill bit arranged in the second joint and in sliding connection with the second joint are arranged in the outer sleeve, and a piston in sliding connection with the air cylinder is arranged in the air cylinder; the air inlet non-return reversing mechanism comprises a valve seat, a plug body, a first spring part and a rigid ball body, the valve seat is fixedly arranged in the outer sleeve, the plug body is arranged on the valve seat in a vertically sliding mode, the first spring part is located between the valve seat and the plug body, and the rigid ball body can roll on the plug body and is abutted against a first central through hole of the first joint under the action of the first spring part to block the first central through hole; through the technical scheme, the problems of easy degumming, easy deformation, short service life and the like of sealing by adopting the sealant are avoided, and the sealing device has the advantages of good sealing effect, long service life and the like.

Description

Down-the-hole hammer

Technical Field

The invention relates to the technical field of mine and tunnel engineering machinery, in particular to a down-the-hole hammer.

Background

In recent years, with the increasing investment on infrastructure and various mines in China, the pneumatic down-the-hole hammer is greatly valued in the technical field of rock crushing machinery by virtue of the advantages of simple structure, convenience in operation and maintenance, capability of effectively removing rock debris at the bottom of a well, no limitation of drilling depth, capability of reducing abrasion of a drilling tool and the like. With the rapid development of the drilling technology of the pneumatic down-the-hole hammer, the application field of the pneumatic down-the-hole hammer is continuously widened, and the pneumatic down-the-hole hammer is gradually developed from initial blast hole construction to almost all drilling construction fields of hydrographic well drilling, geological core exploration, reservoir dam foundation curtain grouting, engineering geological exploration, trenchless pipeline laying, building foundation, geotechnical engineering and the like.

The pneumatic down-the-hole hammer uses high-pressure air as a power source to drive a piston in the hammer to reciprocate at high speed and high frequency, so that the piston obtains enough energy to impact a drill bit to drill. The impact force acts on the drill bit in the form of stress waves, huge impact energy is generated within a very short time, rocks can be effectively crushed, holes can be formed quickly, and the purpose of drilling the rocks and the holes is achieved.

However, when the down-the-hole hammer stops providing high-pressure gas, the inside of the down-the-hole hammer needs to adopt a gas inlet non-return reversing mechanism to prevent the gas from returning to the internal channel of the rear joint, so that slag is returned from the inside of the down-the-hole hammer. The main body of the air inlet non-return reversing mechanism is a steel body, and the surface of the big end of the steel body is fixed with sealant, so that the air inlet non-return reversing mechanism has good sealing effect on the through hole in the rear joint. However, in the existing air inlet non-return reversing mechanism, the connection between the surface of the steel body and the sealant is not firm enough, and the sealant is easy to fall off from the steel body in the working process, so that the air inlet non-return reversing mechanism cannot play a sealing role, slag returns in the impactor, the piston is blocked, and the down-the-hole impactor cannot work normally.

Therefore, the down-the-hole hammer disclosed in chinese patent publication No. CN207583310U includes a hammer body, the hammer body includes a gas distribution seat and an air inlet reverse stopping reversing mechanism installed on the gas distribution seat, the air inlet reverse stopping reversing mechanism is used for one-way sealing the through hole inside the rear joint, the air inlet reverse stopping reversing mechanism includes an air inlet reverse stopping reversing mechanism main body and a sealant, the air inlet reverse stopping reversing mechanism main body is elastically installed on the gas distribution seat, the head of the air inlet reverse stopping reversing mechanism main body is provided with a first opening, and the sealant is fixed on the surface of the head of the air inlet reverse stopping reversing mechanism main body and extends into the first opening to form a fixing column. The head of the air inlet non-return reversing mechanism main body of the down-the-hole hammer is provided with the first opening, the sealant forms a fixing column in the first opening, the contact area between the sealant and the air inlet non-return reversing mechanism main body is increased, the sealant and the air inlet non-return reversing mechanism main body are firmly and reliably fixed, and the problem that the sealant is easy to fall off is effectively solved.

However, the following technical problems are found by those skilled in the art during the use process: in the working process of the down-the-hole impactor, the high-pressure gas always impacts the sealant, so that the temperature of the sealant rises and generates small deformation, the temperature rise of the sealant can make the sealant deform more easily, under the working condition, the sealing performance of the sealant can be reduced very quickly, the service life of the sealant is not long, the sealant needs to be replaced periodically, and therefore if the sealant is firmly connected with the air inlet non-return reversing mechanism main body, the replacement of the sealant is troublesome, if the sealant is not firmly connected with the air inlet non-return reversing mechanism main body, the sealant can easily fall off from the air inlet non-return reversing mechanism main body.

Disclosure of Invention

In order to solve the technical problems, the invention aims to overcome the defects of the prior art and provide the down-the-hole hammer, wherein the air inlet non-return reversing mechanism in the down-the-hole hammer adopts a steel ball to complete the sealing work, so that a series of problems caused by adopting a sealant are avoided.

In order to achieve the purpose, the invention adopts the following technical scheme:

a down-the-hole impactor comprises an outer sleeve, wherein a first joint fixedly connected with the upper end of the outer sleeve, an air inlet non-return reversing mechanism hermetically connected with the first joint, an air cylinder matched and mounted with the inner wall of the outer sleeve, a second joint fixedly connected with the lower end of the outer sleeve and a drill bit arranged in the second joint and slidably connected with the second joint are sequentially arranged in the outer sleeve from top to bottom, and a piston slidably connected with the air cylinder is arranged in the air cylinder; the upper end of the cylinder is matched with a valve seat and forms a second stroke air chamber, the lower end of the cylinder is matched with a guide sleeve and forms a return air chamber, and an air passage for conveying air to the return air chamber is formed between the cylinder and the outer sleeve; the first joint is provided with a first central through hole for introducing high-pressure gas, and the high-pressure gas enables a piston in a cylinder to reciprocate up and down to continuously impact a drill bit from top to bottom so as to complete down-the-hole impact operation; it is characterized in that the preparation method is characterized in that,

the air inlet reverse-stopping reversing mechanism comprises a valve seat, a plug body, a first spring part and a rigid ball body, wherein the valve seat is fixedly installed in the outer sleeve, the plug body can be installed on the valve seat in a vertical sliding mode, the first spring part is located between the valve seat and the plug body, and the rigid ball body can roll on the plug body and is abutted against a first central through hole of the first joint to block the first central through hole under the action of the first spring part.

Preferably, the upper end surface of the plug body comprises a concave curved surface part and a plane part positioned at the bottom end of the curved surface part, the rigid ball rolls back and forth on the plane part, and the concave depth of the curved surface part is smaller than the radius of the rigid ball.

Preferably, the first central through hole includes a fourth hole and a fifth hole connected to each other, the fourth hole is located above the fifth hole, the fifth hole is a conical hole, the diameter of the fifth hole gradually decreases from bottom to top to be the same as that of the fourth hole, the maximum diameter of the fifth hole is larger than that of the rigid sphere, and the minimum diameter of the fifth hole is smaller than that of the rigid sphere.

Preferably, the rigid spheres are made of metal, including gray cast iron, malleable cast iron, nodular cast iron, carbon steel, copper alloy, and stainless steel.

Preferably, the inner side wall of the outer sleeve is provided with a first annular large groove and a second annular large groove which are connected, the first annular large groove is located above the second annular large groove, the radius of the first annular large groove is larger than that of the second annular large groove, the lower end face of the cylinder abuts against the lower side face of the second annular large groove, and the upper end face of the cylinder abuts against the valve seat.

Preferably, the valve seat is a stepped shaft and comprises a first shaft body, a second shaft body, a third shaft body and a fourth shaft body which are different in diameter from top to bottom, the lower end face of the first shaft body abuts against the upper end face of the cylinder, the upper end face of the first shaft body abuts against the lower end face of the first joint, and the third shaft body is in interference fit with the cylinder.

Preferably, the piston is a stepped shaft and comprises a fifth shaft body, a sixth shaft body, a seventh shaft body and an eighth shaft body which are different in diameter from top to bottom, the diameters of the seventh shaft body, the fifth shaft body, the sixth shaft body and the eighth shaft body are sequentially reduced, the fifth shaft body is in sliding fit with the inner side wall of the cylinder, and the eighth shaft body is in sliding fit with the inner side wall of the guide sleeve; the seventh shaft body is in sliding fit with the inner side wall of the outer sleeve.

Preferably, the diameters of the first shaft body, the third shaft body, the second shaft body and the fourth shaft body are sequentially reduced, a plurality of axial first vent holes are uniformly distributed on the first shaft body in the circumferential direction, a plurality of second vent holes and third vent holes are uniformly distributed on the cylinder in the circumferential direction, the second vent holes are located between the first shaft body and the third shaft body, the third vent holes are located between the fifth shaft body and the seventh shaft body, and the second vent holes are inclined holes for guiding gas to move downwards.

Preferably, the diameter of the second shaft body is larger than the diameters of the first shaft body, the third shaft body and the fourth shaft body, a plurality of fourth notches are uniformly distributed on the second shaft body in the circumferential direction, the fourth notches are located at the connecting position of the upper end face of the second shaft body and the side wall of the second shaft body, and high-pressure gas enters the air passage through the fourth notches.

Preferably, a third annular big groove is arranged on the inner side wall of the outer sleeve, a fourth annular big groove is arranged on the inner side wall of the cylinder, when the side wall of the seventh shaft body is in sliding fit with the inner side wall of the outer sleeve above the third large annular groove and the fifth shaft body is positioned below the fourth large annular groove, the fifth shaft body, the sixth shaft body, the seventh shaft body, the inner side wall of the cylinder and the inner side wall of the outer sleeve are matched to form a first stroke air chamber of the piston, when the side wall of the fifth shaft body is in sliding fit with the inner side wall of the cylinder, which is positioned above the fourth annular large groove, the lower end surface of the third shaft body on the valve seat, the inner side wall of the cylinder and the fifth shaft body of the piston are matched to form a second stroke air chamber of the piston, when the side wall of the seventh shaft body is in sliding fit with the inner side wall of the outer sleeve pipe below the third large annular groove, the seventh shaft body, the eighth shaft body, the guide sleeve and the inner side wall of the outer sleeve are matched to form a return air chamber of the piston.

The invention has the beneficial effects that: the rigid ball body is abutted against the first central through hole through the action of the first spring part, so that the sealing effect is achieved, the problems of easy degumming, easy deformation, short service life and the like of sealing by adopting a sealant are solved, and the sealing device has the advantages of good sealing effect, long service life and the like; in addition, the rigid ball body is more beneficial to the circulation of high-pressure gas compared with the sealant.

Drawings

FIG. 1 is a cross-sectional view of a down-the-hole impactor in accordance with one embodiment of the invention;

FIG. 2 is a schematic structural diagram of a plug body according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a valve seat according to a first embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a cylinder according to a first embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a piston according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of an outer sleeve according to an embodiment of the present invention;

FIG. 7 is a schematic structural view of a cylinder according to a second embodiment of the present invention;

fig. 8 is a schematic structural view of a valve seat according to a second embodiment of the present invention.

Description of reference numerals: 1. an outer sleeve; 2. a first joint; 4. a cylinder; 5. a second joint; 6. a piston; 31. a valve seat; 32. a plug body; 33. a first spring member; 34. a rigid sphere; 321. a curved surface portion; 322. a planar portion; 21. a first central through hole; 311. a second central through hole; 323. a helical groove; 11. a first large annular groove; 12. a second annular large groove; 312. a first shaft body; 313. a second shaft body; 314. a third shaft body; 315. a fourth shaft body; 61. a fifth shaft body; 62. a sixth shaft body; 63. a seventh shaft body; 64. an eighth shaft body; 13. a third annular large groove; 41. a fourth annular large groove; 65. a first notch; 66. a second notch; 67. a third notch; 81. a first small annular groove; 82. a second small annular groove; 83. a third small annular groove; 84. a fourth annular small groove; 14. a fifth annular large groove; 7. a guide sleeve; 317. a fourth notch; 316. a first vent hole; 42. a second vent hole; 43. and a third vent hole.

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 drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered as limiting the present 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, unless otherwise specified, "a plurality" means two or more unless explicitly defined otherwise.

In the present invention, unless otherwise expressly specified 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 connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. 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, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the invention, the side surface of the large annular groove refers to a plane vertical to the inner side wall of the outer sleeve, and the bottom surface of the large annular groove refers to a curved surface parallel to the inner side wall of the outer sleeve.

The first embodiment is as follows:

a down-the-hole impactor comprises an outer sleeve 1, wherein a first joint 2 fixedly connected with the upper end of the outer sleeve 1, an air inlet non-return reversing mechanism hermetically connected with the first joint 2, an air cylinder 4 installed in cooperation with the inner wall of the outer sleeve 1, a second joint 5 fixedly connected with the lower end of the outer sleeve 1 and a drill bit arranged in the second joint 5 and slidably connected with the second joint 5 are sequentially arranged in the outer sleeve 1 from top to bottom, and a piston 6 slidably connected with the air cylinder 4 is arranged in the air cylinder 4;

the upper end of the cylinder 4 is matched with a valve seat 31 and forms a second stroke air chamber, the lower end of the cylinder 4 is matched with a guide sleeve 7 and forms a return air chamber, and an air passage for conveying air to the return air chamber is formed between the cylinder 4 and the outer sleeve 1; the first joint 2 is provided with a first central through hole 21 for introducing high-pressure gas, and the high-pressure gas enables a piston 6 in a cylinder 4 to reciprocate up and down to continuously impact a drill bit from top to bottom so as to complete down-the-hole impact operation;

in this embodiment, the intake reverse-stopping mechanism includes a valve seat 31, a plug 32, a first spring member 33 and a rigid ball 34, the valve seat 31 is fixedly installed in the outer sleeve 1, the plug 32 is slidably installed on the valve seat 31 up and down, the first spring member 33 is located between the valve seat 31 and the plug 32, and the rigid ball 34 can roll on the plug 32 and abut against the first central through hole 21 of the first connector 2 under the action of the first spring member 33 to block the first central through hole 21.

Due to the arrangement, the rigid ball 34 is abutted against the first central through hole 21 through the action of the first spring part 33, so that the sealing effect is achieved, the problems of easy degumming, easy deformation, short service life and the like of sealing by adopting sealant are solved, and the sealing device has the advantages of good sealing effect, long service life and the like; in addition, the rigid ball 34 is more conducive to the flow of high pressure gas than the sealant.

In this embodiment, the upper end surface of the plug body 32 includes a concave curved surface portion 321 and a flat surface portion 322 at the bottom end of the curved surface portion 321, the rigid ball 34 rolls back and forth on the flat surface portion 322, and the concave depth of the curved surface portion 321 is smaller than the radius of the rigid ball 34; the arrangement is such that the air inlet non-return reversing mechanism in the embodiment is a floating and self-centering sealing valve, that is, in the sealing process, the rigid ball 34 is adjusted to the optimal sealing position through continuous rolling, the curved surface portion 321 functions to prevent the rigid ball 34 from rolling out of the range of the plane portion 322, and the concave depth of the curved surface portion 321 is smaller than the radius of the rigid ball 34 to prevent the plug body 32 from contacting the first joint 2; the sealing effect is affected;

in addition, the original air inlet reverse stopping reversing mechanism is heavy, the coaxiality between the plug body 32 and the first central through hole 21 needs to be guaranteed, the precision requirement on assembly is high, the steel ball type air inlet reverse stopping reversing mechanism has a self-centering effect, even if the coaxiality between the plug body 32 and the first central through hole 21 is not high, the sealing effect can be achieved, in addition, the steel ball type air inlet reverse stopping reversing mechanism is light, and therefore even if the first spring part 33 fails, the sealing effect can be achieved under the internal and external pressure difference.

In this embodiment, the first central through hole 21 includes a fourth hole and a fifth hole connected to each other, the fourth hole is located above the fifth hole, the fifth hole is a conical hole, and the diameter of the fifth hole gradually decreases from bottom to top to be the same as that of the fourth hole, wherein the maximum diameter of the fifth hole is larger than the diameter of the rigid sphere 34, and the minimum diameter of the fifth hole is smaller than the diameter of the rigid sphere 34.

Further preferably, the rigid spheres 34 are made of metal, including gray cast iron, malleable cast iron, ductile cast iron, carbon steel, copper alloy, stainless steel, and the like.

In this embodiment, a second central through hole 311 is formed in the valve seat 31, the second central through hole 311 includes a first hole, a second hole and a third hole, the diameters of which are sequentially reduced from top to bottom, the plug body 32 reciprocates up and down in the first hole, a first mounting hole is formed in the lower end face of the plug body 32, the top end of the first spring member 33 abuts against the bottom end of the first mounting hole, and the bottom end of the first spring member 33 abuts against a step face between the second hole and the third hole.

In this embodiment, the plug body 32 has a spiral groove 323 on a side wall surface thereof. This arrangement is for the convenience to lubricate the lateral wall face of cock body 32 and the inside wall face of first hole, and then prevents that cock body 32 from causing the fracture because of the friction is too big, improves cock body 32's life.

In this embodiment, a first large annular groove 11 and a second large annular groove 12 connected to each other are formed in the inner side wall of the outer sleeve 1, the first large annular groove 11 is located above the second large annular groove 12, the radius of the first large annular groove 11 is larger than that of the second large annular groove 12, the lower end surface of the cylinder 4 abuts against the lower side surface of the second large annular groove 12, and the upper end surface of the cylinder 4 abuts against the valve seat 31; so set up, reduced the length of cylinder 4, reduced the cracked risk of cylinder 4.

Preferably, the cylinder 4 comprises a first ring body, a second ring body and a third ring body from top to bottom, wherein the first ring body, the second ring body and the third ring body are different in diameter, the first ring body is in interference fit with the inner side wall of the outer sleeve 1, and the third ring body is in interference fit with the second large annular groove 12; this is provided so that the cylinder 4 can be stably mounted in the outer tube 1.

In this embodiment, the valve seat 31 is a stepped shaft, and includes a first shaft body 312, a second shaft body 313, a third shaft body 314, and a fourth shaft body 315 with different diameters from top to bottom, the diameters of the first shaft body 312, the third shaft body 314, the second shaft body 313, and the fourth shaft body 315 are sequentially reduced, the lower end surface of the first shaft body 312 abuts against the upper end surface of the cylinder 4, the upper end surface of the first shaft body 312 abuts against the lower end surface of the first joint 2, and the third shaft body 314 is in interference fit with the cylinder 4; this is provided so that the valve seat 31 can be securely mounted in the outer sleeve 1.

In this embodiment, the piston 6 is a stepped shaft and includes a fifth shaft body 61, a sixth shaft body 62, a seventh shaft body 63 and an eighth shaft body 64 with different diameters from top to bottom, the diameters of the seventh shaft body 63, the fifth shaft body 61, the sixth shaft body 62 and the eighth shaft body 64 are sequentially reduced, the fifth shaft body 61 is in sliding fit with the inner side wall of the cylinder 4, and the eighth shaft body 64 is in sliding fit with the inner side wall of the guide sleeve 7; the seventh shaft 63 is in sliding fit with the inner side wall of the outer sleeve 1,

a third annular big groove 13 is arranged on the inner side wall of the outer sleeve 1, a fourth annular big groove 41 is arranged on the inner side wall of the cylinder 4, when the side wall of the seventh shaft body 63 is in sliding fit with the inner side wall of the outer sleeve 1 which is positioned above the third annular big groove 13 and the fifth shaft body 61 is positioned below the fourth annular big groove 41, the fifth shaft body 61, the sixth shaft body 62, the seventh shaft body 63, the inner side wall of the cylinder 4 and the inner side wall of the outer sleeve 1 are matched to form a first stroke air chamber of the piston 6, when the side wall of the fifth shaft body 61 is in sliding fit with the inner side wall of the cylinder 4 which is positioned above the fourth annular big groove 41, the lower end surface of the third shaft body 314 on the valve seat 31, the inner side wall of the cylinder 4 and the fifth 61 of the piston 6 are matched to form a second stroke air chamber of the piston 6, when the side wall of the seventh shaft body 63 is in sliding fit with the inner, the seventh shaft 63, the eighth shaft 64, the guide sleeve 7 and the inner side wall of the outer sleeve 1 cooperate to form a return air chamber of the piston 6.

Preferably, a plurality of first notches 65 and second notches 66 are uniformly distributed on the seventh shaft body 63 in a circumferential manner, the first notches 65 are located at a joint between the side wall of the seventh shaft body 63 and the upper end surface of the seventh shaft body 63, and the second notches 66 are located at a joint between the side wall of the seventh shaft body 63 and the lower end surface of the seventh shaft body 63, so that the first stroke air chamber and the return stroke air chamber can be switched within a certain buffer time, and the buffer time is not too long, that is, when the first stroke air chamber and the return stroke air chamber are switched, the stroke of the piston 6 is controlled within a certain range, and the piston 6 is ensured to have a strong impact force.

Preferably, a plurality of third notches 67 are circumferentially and uniformly distributed on the fifth shaft body 61, the third notches 67 are located at the connecting position of the upper end surface of the fifth shaft body 61 and the side wall of the fifth shaft body 61, and therefore the arrangement is mainly convenient for air to enter the second stroke air chamber, and the piston 6 is ensured to have strong impact force.

In the present embodiment, the piston 6 forms a labyrinth seal with at least one of the cylinder 4, the guide sleeve 7, the valve seat 31, and the outer sleeve 1 during the up-and-down sliding; further preferably, the piston 6 forms a labyrinth seal with the cylinder 4, the guide sleeve 7, the valve seat 31 and the outer sleeve 1 in the process of sliding up and down.

Preferably, a plurality of parallel first small annular grooves 81 are further provided, the plurality of parallel first small annular grooves 81 are located on the side wall of the fourth shaft body 315 or the fifth central through hole, and in the up-and-down sliding process of the piston 6, the fourth shaft body 315 and the fifth central through hole are matched to form a labyrinth seal.

Preferably, a plurality of parallel second annular small grooves 82 are further arranged, the plurality of parallel second annular small grooves 82 are located on the side wall of the fifth shaft body 61 or the inner side wall of the cylinder 4, and in the process that the piston 6 slides up and down, the fifth shaft body 61 and the inner side wall of the cylinder 4 are matched to form a labyrinth seal; further preferably, when the plurality of parallel second annular small grooves 82 are located on the inner side wall of the cylinder 4, the plurality of parallel second annular small grooves 82 are located above the fourth annular large groove 41.

Preferably, a plurality of parallel third annular small grooves 83 are further provided, the plurality of parallel third annular small grooves 83 are located on the side wall of the seventh shaft body 63 or the inner side wall of the outer sleeve 1, and in the process of up-and-down sliding of the piston 6, the seventh shaft body 63 and the inner side wall of the outer sleeve 1 are matched to form a labyrinth seal; it is further preferred that the plurality of parallel third small annular grooves 83 are located between the third large annular groove 13 and the second large annular groove 12 when the plurality of parallel third small annular grooves 83 are located on the inner side wall of the outer sleeve 1.

Preferably, a plurality of parallel fourth annular small grooves 84 are further provided, the plurality of parallel fourth annular small grooves 84 are located on the side wall of the eighth shaft body 64 or the inner side wall of the guide sleeve 7, and the eighth shaft body 64 and the inner side wall of the guide sleeve 7 cooperate to form a labyrinth seal in the up-and-down sliding process of the piston 6.

With such arrangement, the added first annular small groove 81, second annular small groove 82, third annular small groove 83 and fourth annular small groove 84 play a role of labyrinth seal, so that the piston 6 can obtain larger energy to impact the drill bit, so as to improve the drilling efficiency, and on the other hand, when the impactor is used for preventing foreign matters from entering the impactor during the drilling process, the first annular small groove 81, second annular small groove 82, third annular small groove 83 and fourth annular small groove 84 play a role of temporary foreign matter storage, so as to prevent the foreign matters from damaging thin-wall parts such as the cylinder 4, the outer sleeve 1 and the guide sleeve 7 during the sliding process of the piston 6, and meanwhile, the added first annular small groove 81, second annular small groove 82, third annular small groove 83 and fourth annular small groove 84 also reduce the contact area of the piston 6 during the sliding process, making sliding easier and reducing energy losses during sliding.

In this embodiment, a plurality of first vent holes 316 are uniformly distributed on the first shaft body 312 in a circumferential direction, a plurality of axial second vent holes 42 and a plurality of axial third vent holes 43 are uniformly distributed on the cylinder 4 in a circumferential direction, the second vent holes 42 are located between the first shaft body 312 and the third shaft body 314, the third vent holes 43 are located between the fifth shaft body 61 and the seventh shaft body 63, and the second vent holes 42 are inclined holes for guiding the gas to move downward.

In this embodiment, a fifth annular large groove 14 is further disposed on the inner side wall of the outer sleeve 1, the fifth annular large groove 14 is in interference fit with a part of the side wall of the guide sleeve 7 to further limit the upward movement of the guide sleeve 7, and the lower end surface of the guide sleeve 7 abuts against the upper end surface of the second joint 5.

The specific flow path of the high-pressure gas is as follows:

when high-pressure gas enters the impactor from the first central through hole 21, the high-pressure gas sequentially passes through the first vent hole 316 and the second vent hole 42 and then enters a gap between the cylinder 4 and the outer sleeve 1, and then passes through the third vent hole 43 and then enters a gap between the piston 6 and the outer sleeve 1, generally, the seventh shaft body 63 on the piston 6 is located at the third annular big groove 13, namely, the high-pressure gas enters the return air chamber, so that the piston 6 is pushed to move upwards, when the piston 6 moves until the eighth shaft body 64 is separated from the guide sleeve 7, the high-pressure gas in the return air chamber reaches the bottom of the drill from the inner hole of the guide sleeve 7 and the inner hole of the drill and is discharged, so that the slag blowing function is realized, and the air pressure in the return air chamber is rapidly reduced;

meanwhile, the seventh shaft body 63 of the piston 6 moves to the upper part of the third annular big groove 13, the air inlet channel of the return air chamber is closed, namely, a first stroke air chamber is formed, but the piston 6 can still continue to do certain return movement by means of inertia at the moment and is always blocked by the first stroke force formed by the air inlet pressure until the piston stops; the first stroke force is generated by high-pressure gas entering the first stroke air chamber and impacting the seventh shaft body 63 with a larger diameter, but the high-pressure gas entering the first stroke air chamber enters the second stroke air chamber along a gap between the fifth shaft body 61 and the fourth annular large groove 41, namely the first stroke force is not large, so that the piston 6 can move for a certain distance by overcoming the first stroke force through inertia during the return stroke;

after the piston 6 continues to perform the return movement until the seventh shaft body 63 and the plurality of parallel second annular small grooves 82 form labyrinth seals and the plurality of parallel fourth annular small grooves 84 and the inner side wall of the piston 6 form labyrinth seals, the first stroke force in the first stroke air chamber and the second stroke force in the second stroke air chamber are greatly increased, and then the piston 6 starts to perform the stroke movement to strike the drill bit to do work, thereby completing the rock breaking work.

It is worth mentioning that the structure of the drill bit can refer to the drill bit parts referred to in the publications CN202023506U, CN202431197U, CN202431199U, CN202431200U, CN202954743U, CN203081307U, CN203441372U, CN203531754U, CN204060518U, and CN205778544U, and in general, the drill bit comprises a working part for drilling and a connecting part for connecting with a down-the-hole hammer, wherein the connecting part is provided with spline grooves, and the connecting part is circumferentially fixed and slidably connected with the down-the-hole hammer through the spline grooves.

Example two:

the difference between the present embodiment and the first embodiment is that the inlet passage of the high-pressure gas is different after the high-pressure gas enters the interior of the impactor.

In this embodiment, the high-pressure gas enters the interior of the down-the-hole hammer through the first central through hole 21 and then directly enters the gap between the cylinder 4' and the outer sleeve 1.

Specifically, the diameter of the second shaft body 313 ' is greater than the diameters of the first shaft body 312 ', the third shaft body 314 ' and the fourth shaft body 315 ', a plurality of fourth notches 317 are uniformly distributed on the second shaft body 313 ' in a circumferential manner, the plurality of fourth notches 317 are located at the connecting position of the upper end surface of the second shaft body 313 ' and the side wall of the second shaft body 313 ', and the high-pressure gas enters the gas passage through the plurality of fourth notches 317.

Further preferably, the bottom surface of the fourth notch 317 is a smooth curved surface or a flat surface.

In this embodiment, the lower half of the cylinder 4 ' is mounted on the same embodiment, the upper half of the cylinder 4 ' is mounted on a different embodiment, and the specific mounting structure of the upper half of the cylinder 4 ' is as follows: the upper end surface of the cylinder 4 ' is abutted against the lower end surface of the second shaft body 313 ', and the inner side wall of the cylinder 4 ' is in interference fit with the third shaft body 314 ' of the valve seat 31 '.

By the arrangement, the gas inlet mode of the high-pressure gas is changed, so that the high-pressure gas can move more smoothly in the down-the-hole impactor; secondly, the length of the cylinder 4' is reduced, so that the length of the whole down-the-hole hammer is reduced, and the cost is saved; finally, in the original air intake mode, high-pressure air enters the gap between the cylinder 4 'and the outer sleeve 1 from the inside of the cylinder 4' through the inclined hole at the upper part of the cylinder 4 ', and the inclined hole at the upper part of the cylinder 4' can be omitted through the air intake mode in the embodiment, so that the processing cost is saved.

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 do not necessarily 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.

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 in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A down-the-hole impactor comprises an outer sleeve (1), wherein a first joint (2) fixedly connected with the upper end of the outer sleeve (1), an air inlet non-return reversing mechanism hermetically connected with the first joint (2), an air cylinder (4) installed in a matched mode with the inner wall of the outer sleeve (1), a second joint (5) fixedly connected with the lower end of the outer sleeve (1) and a drill bit arranged in the second joint (5) and connected with the second joint (5) in a sliding mode are sequentially arranged in the outer sleeve (1) from top to bottom, and a piston (6) connected with the air cylinder (4) in a sliding mode is arranged in the air cylinder (4); the upper end of the cylinder (4) is matched with the valve seat (31) to form a second stroke air chamber, the lower end of the cylinder (4) is matched with the guide sleeve (7) to form a return air chamber, and an air passage for conveying air to the return air chamber is formed between the cylinder (4) and the outer sleeve (1); the first joint (2) is provided with a first central through hole (21) for introducing high-pressure gas, and the high-pressure gas enables a piston (6) in a cylinder (4) to reciprocate up and down to continuously impact a drill bit from top to bottom so as to complete down-the-hole impact operation; it is characterized in that the preparation method is characterized in that,

the air inlet non-return reversing mechanism adopts a rigid ball (34) to complete the sealing of the first central through hole (21).

2. A down-the-hole hammer as set forth in claim 1, characterized in that the air inlet reverse-flow prevention mechanism further comprises a valve seat (31), a plug body (32) and a first spring member (33), the valve seat (31) is fixedly mounted in the outer sleeve (1), the plug body (32) is slidably mounted on the valve seat (31) up and down, the first spring member (33) is located between the valve seat (31) and the plug body (32), and the rigid ball (34) can roll on the plug body (32) and abut against the first central through hole (21) of the first joint (2) under the action of the first spring member (33) to block the first central through hole (21).

3. A down-the-hole impactor as defined in claim 2, wherein the upper end surface of the plug body (32) includes a concave curved surface portion (321) and a flat surface portion (322) at the bottom end of the curved surface portion (321), the rigid ball (34) rolling back and forth over the flat surface portion (322), the concave depth of the curved surface portion (321) being less than the radius of the rigid ball (34).

4. A down-the-hole impactor as claimed in claim 1, wherein the first central through hole (21) comprises a fourth hole and a fifth hole connected together, the fourth hole being located above the fifth hole, the fifth hole being a conical hole, the fifth hole decreasing in diameter from bottom to top to the same as the fourth hole, wherein the maximum diameter of the fifth hole is greater than the diameter of the rigid ball (34) and the minimum diameter of the fifth hole is less than the diameter of the rigid ball (34).

5. A down-the-hole impactor as defined in claim 1, wherein said rigid ball (34) is of a metallic material, including gray cast iron, malleable cast iron, ductile cast iron, carbon steel, copper alloys, and stainless steel.

6. A down-the-hole hammer as claimed in claim 1, characterised in that the outer casing (1) has a first annular large recess (11) and a second annular large recess (12) connected to each other on its inner side wall, the first annular large recess (11) is located above the second annular large recess (12), the radius of the first annular large recess (11) is greater than the radius of the second annular large recess (12), the lower end face of the cylinder (4) abuts against the lower side face of the second annular large recess (12), and the upper end face of the cylinder (4) abuts against the valve seat (31).

7. A down-the-hole impactor as claimed in claim 1, characterized in that the valve seat (31) is a stepped shaft comprising, from top to bottom, a first shaft body (312), a second shaft body (313), a third shaft body (314) and a fourth shaft body (315) of different diameters, the lower end face of the first shaft body (312) abutting against the upper end face of the cylinder (4), the upper end face of the first shaft body (312) abutting against the lower end face of the first joint (2), the third shaft body (314) being in interference fit with the cylinder (4).

8. A down-the-hole impactor as claimed in claim 7, characterised in that the diameters of the first shaft body (312), the third shaft body (314), the second shaft body (313) and the fourth shaft body (315) decrease in sequence, a plurality of axial first vent holes (316) are circumferentially and uniformly distributed on the first shaft body (312), a plurality of second vent holes (42) and third vent holes (43) are circumferentially and uniformly distributed on the cylinder (4), the second vent holes (42) are located between the first shaft body (312) and the third shaft body (314), the third vent holes (43) are located between the fifth shaft body (61) and the seventh shaft body (63), and the second vent holes (42) are oblique holes for guiding gas to move downwards.

9. A down-the-hole impactor as claimed in claim 7, wherein the diameter of the second shaft body (313 ') is greater than the diameters of the first shaft body (312 '), the third shaft body (314 ') and the fourth shaft body (315 '), wherein a plurality of fourth notches (317) are uniformly distributed on the second shaft body (313 ') in a circumferential manner, the plurality of fourth notches (317 ') are located at the connecting position of the upper end face of the second shaft body (313 ') and the side wall of the second shaft body (313 '), and the high-pressure gas enters the gas channel through the plurality of fourth notches (317 ').

10. A down-the-hole hammer as claimed in claim 1, characterised in that the piston (6) is a stepped shaft comprising, from top to bottom, a fifth shaft body (61), a sixth shaft body (62), a seventh shaft body (63) and an eighth shaft body (64) of different diameters, the diameters of the seventh shaft body (63), the fifth shaft body (61), the sixth shaft body (62) and the eighth shaft body (64) decreasing in sequence, the fifth shaft body (61) being in sliding engagement with the inner side wall of the cylinder (4), the eighth shaft body (64) being in sliding engagement with the inner side wall of the guide sleeve (7); the seventh shaft body (63) is in sliding fit with the inner side wall of the outer sleeve (1);

a third annular large groove (13) is arranged on the inner side wall of the outer sleeve (1), a fourth annular large groove (41) is arranged on the inner side wall of the cylinder (4), when the side wall of a seventh shaft body (63) is in sliding fit with the inner side wall, which is positioned above the third annular large groove (13), in the outer sleeve (1) and a fifth shaft body (61) is positioned below the fourth annular large groove (41), the fifth shaft body (61), the sixth shaft body (62), the seventh shaft body (63), the inner side wall of the cylinder (4) and the inner side wall of the outer sleeve (1) are matched to form a first stroke air chamber of the piston (6), when the side wall of the fifth shaft body (61) is in sliding fit with the inner side wall, which is positioned above the fourth annular large groove (41), in the cylinder (4), the lower end face of the third shaft body (314) on the valve seat (31), the inner side wall of the cylinder (4) and the fifth shaft body (61) of the piston (6) are matched to form a second stroke air, when the side wall of the seventh shaft body (63) is in sliding fit with the inner side wall of the outer sleeve (1) below the third annular large groove (13), the seventh shaft body (63), the eighth shaft body (64), the guide sleeve (7) and the inner side wall of the outer sleeve (1) are matched to form a return air chamber of the piston (6).

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