AU2015282366B2 - Down-the-Hole Impactor - Google Patents

Abstract

A down-the-hole impacter includes a rear adapter, an outer pipe sleeve, a front adapter and a drill bit, wherein the rear adapter is connected to one end of the outer pipe sleeve, the other end of the outer pipe sleeve is connected to the front adapter, the drill bit is installed inside the front adapter through a snap ring, an inner cylinder is installed in the outer pipe sleeve, a gas distribution rod is installed in the cavity body of the inner cylinder, a check valve is matched with a spring to install in the inner cavity at the end portion of the gas distribution rod, a piston is installed in the cavity body of the outer pipe sleeve and forms a sliding connection with the terminal of the piston, and the outer pipe sleeve is provided with a retainer ring for positioning a guide sleeve. With the above arrangement, the output power of the impacter can be increased and the leakage of the high-pressure gas can be effectively decreased, so that the structure is more compact and reasonable, thereby prolonging the service life of the impacter. r14 p, 13 g12 -11 -10r -9 -7 ,4 ,,5 /-27 4A 3/2I "I "C 17 J26 R 2 - Fig. 1 A8 3; Fo D- E 9 Fg L D Fig. 2-1

Description

DOWN-THE-HOLEIMPACTER 2015282366 29 Dec 2015

Technical Field

The invention relates to a pneumatic impacting equipment, and more particular to a down-the-hole impacter. 5 Background Art A non-valve down-the-hole impacter is a kind of typical pneumatic impacting equipment, which is a drilling tool of a down-the-hole drill and a working mechanism of the drill for drilling a hole. The equipment is mainly used for drilling and blasting a hole with the diameter of 65-305mm and the depth of 60m. The hole drilling efficiency of one 0 down-the-hole drill depends largely on the performance of the impacter. Currently, the down-the-hole impacter used in the market is a HDH series non-valve double-cylinder structure down-the-hole impacter represented by Ingersoll-Rand Company. In the use process, such down-the-hole impacter has the following several disadvantages: (1) a rubber ring is installed between a valve seat and a rear adapter, certainly part of energy is consumed by the 5 impacter itself in working hours, in addition, after the impacter works for a period of time, the rubber is easy to age and deform, resulting in leaping up to reduce the fit precision among various parts, thereby reducing the work efficiency of the impacter and shortening the service life of the impacter; (2) the inner cylinder is a thin-wall structural part, the machining is complicated, the machining cost is high, and it is also easy to damage, which has a strong 20 impact on the use stability of the impacter; (3) a plurality of circular grooves are excavated in the inner wall of an outer pipe sleeve, thereby reducing the abrasive resistance of the outer pipe sleeve; (4) the piston is opened with more gas distribution hole ducts, the gas ducts have a lot of turns and long distance, the gas pressure loss is high, it is easy to generated higher heat, long-term high-temperature operation easily causes stress concentration, and the 25 equipment is often scrapped in advance due to the problems of technique and structure in working hours; and (5) a snap ring is in an oppositely-opening structure, an "O-shaped" seal ring needs to be adopted to band and tighten the drill bit in the assembling process, while the "O-shaped" seal ring is made of rubber, so it is easy to damage due to an outer force and to 1 age and lose efficiency when meeting oil or high temperature, thereby causing the failure of the whole impacting equipment. 2015282366 29 Dec 2015

Therefore, the structure of the original impacter needs to the improved on the basis of the above-mentioned analysis and technical feature, thus the above-mentioned discharges are 5 effectively overcome, the output power of the impacter is increased, the leakage of the high-pressure gas is effectively reduced, the structure is more compact and reasonable, and the service life of the impacter is prolonged.

Summary of the Invention

It is a preferred aim of the invention to provide an improved down-the-hole impacter. 0 In one broad form, the present invention provides a down-the-hole impacter, comprising a rear adapter, an outer pipe sleeve, a front adapter and a drill bit, wherein the rear adapter is connected to one end of the outer pipe sleeve, the other end of the outer pipe sleeve is connected to the front adapter, the drill bit is installed inside the front adapter through a snap ring, an inner cylinder is installed in the outer pipe sleeve, a gas distribution rod is installed in 5 the cavity body of the inner cylinder, a check valve is matched with a spring to install in the inner cavity at the end portion of the gas distribution rod, a piston is installed in the cavity body of the outer pipe sleeve and forms a sliding connection with the terminal of the piston, and the outer pipe sleeve is provided with a retainer ring for positioning a guide sleeve.

In an embodiment, the ratio of the total length of the piston and the maximum outer diameter 20 is less than 3.8, an unique center gas holes is opened in the central position of the piston, the small end of the piston is equipped with a step, the step is in a sliding fit with the guiding sleeve, a guiding section formed by a circular bead and a taper angle is machined in the impacting end face of the piston, the middle part of the piston is equipped with a supporting section matched with the inner hole of the outer pipe sleeve, the large end of the piston is 25 equipped with a large end step, the large end step is in a sliding fit with the inner cylinder, a large end hole forms a batch-type fit with the gas distribution rod in the working process and is communicated with the center gas hole. 2

In an embodiment, the outer edge of the left part portion of the supporting section of the piston is machined with a plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with a third circular groove, the outer edge of the right half portion of the supporting section is 2015282366 29 Dec 2015 5 machined with a plurality of uniformly distributed fourth gas through grooves, the right side shaft diameter close to the supporting section is machined with a first circular groove, the outer edge of the right half portion of the large end step is machined with a plurality of uniformly distributed second gas through grooves, and the outer end face close to the large end hole is machined with a circular recess. 0 In an embodiment, the outer edge of the right half portion of the supporting section of the piston is machined with a plurality of uniformly distributed first gas through grooves, the outer edge of the right half portion of the large end step is machined with a plurality of uniformly distributed second gas through grooves, and the outer end face close to the large end hole is machined with the circular recess. 5 In an embodiment, the outer edge of the left half portion of the supporting section of the piston is machined with the plurality of uniformly distributed first gas through grooves, the outer edge of the right half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves, the outer end face close to the large end hole is machined with the circular recess, the right side shaft diameter close to the supporting 20 section is machined with the first circular groove, and the left side shaft diameter close to the large end step is machined with a second circular groove.

In an embodiment, the outer edge of the left part portion of the supporting section of the piston is machined with the plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with the 25 third circular groove, the right side shaft diameter close to the supporting section is machined with the first circular groove, the outer edge of the right half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves, and the outer end face close to the large end hole is machined with a circular recess. 3

In an embodiment, the outer edge of the left half portion of the supporting section of the piston is machined with the plurality of uniformly distributed first gas through grooves, and the outer edge of the right half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves. 2015282366 29 Dec 2015 5 In an embodiment, the outer edge of the right half portion of the supporting section of the piston is machined with the plurality of uniformly distributed first gas through grooves, and the outer edge of the left half portion of the large end step is machined with a plurality of uniformly distributed fifth gas through grooves.

In an embodiment, the outer edge of the right half portion of the supporting section of the 0 piston is machined with the plurality of uniformly distributed first gas through grooves, the right side shaft diameter close to the supporting section is machined with the first circular groove, and the outer edge of the left half portion of the large end step is machined with the plurality of uniformly distributed fifth gas through grooves.

In an embodiment, the outer edge of the left part portion of the supporting section of the 5 piston is machined with the plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with the third circular groove, the right side shaft diameter close to the supporting section is machined with the first circular groove, and the outer edge of the left half portion of the large end step is machined with the plurality of uniformly distributed fifth gas through grooves. 20 In an embodiment, the outer edge of the left part portion of the supporting section of the piston is machined with the plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with the third circular groove, the outer edge of the right half portion of the supporting section is machined with the plurality of uniformly distributed fourth gas through grooves, the right 25 side shaft diameter close to the supporting section is machined with the first circular groove, the outer edge of the left half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves. 4

In an embodiment, the snap ring is in a subdivision-type structure, one end of the snap ring matched with the drill bit is internally machined with an inner step, the inner step and the outer end face of the drill bit form a sliding fit, the outer round face of the snap ring matched with the front adapter is machined with a transition step, the end face of the snap ring 5 matched with the guide sleeve is machined with an outer step, and the outer step is matched with and positioned with the top end of the front adapter. 2015282366 29 Dec 2015

In an embodiment, the snap ring is in the subdivision-type structure, one end of the snap ring matched with the drill bit is internally machined with the inner step, the inner step and the outer end face of the drill bit form the sliding fit, the end face of the snap ring matched with 0 the guide sleeve is machined with the outer step, and the outer step is matched with and positioned with the top end of the front adapter.

In an embodiment, the gas distribution rod is equipped with a positioning shaft collar, the positioning shaft collar is installed inside the inner cylinder, the left end face of the positioning shaft collar is matched and positioned through the inner shaft shoulder of the 5 inner cylinder, the periphery of the positioning shaft collar is machined with a plurality of uniformly distributed gas distribution rod gas through notches, and the right end face of the positioning shaft ring is matched with the left end face of the rear adapter to press inside the inner cylinder.

In an embodiment, the left end face of the positioning shaft ring is matched with and 20 positioned with the right end face of the inner cylinder, the positioning shaft collar is machined with a plurality of uniformly distributed gas distribution rod gas through notches, and the periphery of the positioning shaft collar is matched with the inner wall of the outer pipe sleeve and the right end face of the positioning shaft collar is matched with and positioned with the left end face of the rear adapter. 25 In an embodiment, the drill bit comprises a steel body and alloy teeth, the front end portion of the steel body is equipped with a non-spline type integrated cylinder impacting step the impacting step and the outer wall of the inner cavity of the snap ring form a sliding fit, the middle part of the outer surface of the steel body is equipped with a plurality of splines, the 5 middle part of the drill bit is equipped with a drill bit center gas hole, the rear end of the steel body is equipped with an inclined gas hole, the drill bit center gas hole is communicated with the inclined gas hole, the installing end face of the alloy teeth is machined with a top portion powder discharging groove communicated with the inclined gas hole, and the side face of the 5 drill bit is machined with a side portion powder discharging groove communicated with the top portion powder discharging groove. 2015282366 29 Dec 2015

The features of the embodiments mentioned above may be combined where appropriate.

The invention has one or more of the beneficial effects described below: 1. The creation and change of the piston structure improve the work efficiency of whole 0 impacter. Through working practices, the piston is designed to enable the ratio of the total length and the maximum outer diameter is less than 3.8, which is more beneficial to strain the quick transmission of the stress wave. In this way, the impacter has a higher output power, so as to increase the work efficiency of the whole impacter. The piston and the output pipe sleeve can be ensured to be in the working condition in cooperation with supporting by 5 setting the step, supporting section and the large end step on the piston. 2. The fitting connection among the gas distribution rod, the inner cylinder and the rear adapter increases the work efficiency. On one hand, the top circle of the inner cylinder is provided with a positioning conical surface matched with the outer pipe sleeve, the positioning shaft collar of the gas distribution rod is installed inside the inner cylinder, the left 20 end face of the positioning shaft collar is matched and positioned by the inner shaft shoulder of the inner cylinder, the circle of the positioning shaft collar is machined with a plurality of uniformly distributed gas distribution rod gas through notches, the right end face of the positioning shaft collar is matched with the left end face of the rear adapter to press inside the inner cylinder, the large end face of the rear adapter urges three parts to form a rigid 25 connection on the end face of the inner cylinder along with the threaded screw-in, thereby avoiding leaping up the gas distribution rod in working hours. As a result, the high-precision cooperation can be kept for long and the work efficiency is ensured. 6 3. The structure of the gas distribution rod designed reasonably. The gas distribution rod and the valve seat are in an integrated structure, the structure is simple and convenient, second, the air distribution rod is uniformly distributed with an air distribution rod air through hole, it is not easy to cause deformation and breakage in working hours, an air distribution 2015282366 29 Dec 2015 5 passage is simple and smooth so as to reduce the energy loss; and third, the matching portion of the air distribution rod and the piston rod is equipped with a plurality of damping grooves, which can effectively reduce the leakage of the high-pressure air. 4. The assembly structure of the snap ring and the front adapter is reasonable. First, the snap ring is in the subdivision-type structure, one end of the snap ring matched with the drill 0 bit is internally machined with the inner step, the inner step and the outer end face of the drill bit form the sliding fit, the end face of the snap ring matched with the guide sleeve is machined with the outer step, and the outer step is matched with and positioned with the top end of the front adapter. Such design abandons that the traditional snap ring is assembled by adopting the O-shaped ring to band and tighten, it is more convenient to assemble and 5 disassemble the impacter; second, compared to the traditional design, the design of partly sinking the snap ring into the front adapter makes the structure more compact and reliable. 5. The participation of the tailless pipe lowers the failure rate of gas distribution. Through the distribution and use of a tailless pipe bit, the impacter adopts the guide sleeve to match with the piston to complete the air distribution, the participation of the tailless pipe bit in the 20 working process lowers the failure rate. The installing end face of the alloy teeth of the drill bit is machined with a top portion powder discharging groove communicated with the inclined air hole, the side face of the drill bit is machined with a side portion powder discharging groove communicated with the top portion powder discharging groove, so that it is convenient to discharge the chiseled rock powder through an air discharging groove in a 25 mode of air outlet, the tail handle of the drill bit has short length and strong strength, thereby effectively shortening the downtime due to the damage of the drill bit.

With the structure described above, the output power of the impacter can be increased and the leakage of the high-pressure gas can be effectively decreased, so that the structure is more 7 compact and reasonable, thereby prolonging the service life of the impacter. 2015282366 29 Dec 2015

Brief Description of the Drawings

The invention is further described hereinafter with reference to drawings and embodiments.

Fig. 1 is an integrated schematic structural diagram of an embodiment of the invention (the 5 piston portion is half section and the other portions are complete section).

Fig. 2-1 is a schematic structural diagram of an I-type piston of an embodiment of the invention.

Fig. 2-2 is an A-A sectional view of the I-type piston.

Fig. 2-3 is a B-B sectional view of the I-type piston. 0 Fig. 3-1 is a schematic structural diagram of an II-type piston of an embodiment of the invention.

Fig. 3-2 is an A-A sectional view of the II-type piston.

Fig. 3-3 is a B-B sectional view of the II-type piston.

Fig. 4-1 is a schematic structural diagram of an Ill-type piston of an embodiment of the 15 invention.

Fig. 4-2 is an A-A sectional view of the Ill-type piston.

Fig. 4-3 is a B-B sectional view of the Ill-type piston.

Fig. 5-1 is a schematic structural diagram of an IV-type piston of an embodiment of the invention. 20 Fig. 5-2 is an A-A sectional view of the IV-type piston.

Fig. 5-3 is a B-B sectional view of the IV-type piston. 8

Fig. 6-1 is a schematic structural diagram of a V-type piston of an embodiment of the invention. 2015282366 29 Dec 2015

Fig. 6-2 is an A-A sectional view and a D-D sectional view of the V-type piston.

Fig. 6-3 is a B-B sectional view of the V-type piston. 5 Fig. 7-1 is a schematic structural diagram of a Vi-type piston of an embodiment of the invention.

Fig. 7-2 is an E-E sectional view of the Vi-type piston.

Fig. 7-3 is a D-D sectional view of the Vi-type piston.

Fig. 8-1 is a schematic structural diagram of a VH-type piston of an embodiment of the 0 invention.

Fig. 8-2 is an E-E sectional view of the VH-type piston.

Fig. 8-3 is a D-D sectional view of the VH-type piston.

Fig. 9-1 is a schematic structural diagram of a VUI-type piston of an embodiment of the invention. 15 Fig. 9-2 is an E-E sectional view of the VUI-type piston.

Fig. 9-3 is a D-D sectional view of the VUI-type piston.

Fig. 10-1 is a schematic structural diagram of an IX-type piston of an embodiment of the invention.

Fig. 10-2 is an E-E sectional view and an F-F sectional view of the IX-type piston. 20 Fig. 10-3 is a D-D sectional view of the IX-type piston.

Fig. 11 is a first assembling structure among a snap ring, a piston and a front adapter of an embodiment of the invention. 9

Fig. 12 is a three-dimensional diagram of a second assembling structure among a snap ring, a piston and a front adapter of an embodiment of the invention. 2015282366 29 Dec 2015

Fig. 13 is a three-dimensional structural diagram of a snap ring of an embodiment of the invention. 5 Fig. 14 is a first assembling structure among a gas distribution rod, an inner cylinder and a rear adapter of an embodiment of the invention.

Fig. 15 is a top view of a positioning shaft ring in the first assembling structure of the gas distribution rod of an embodiment of the invention.

Fig. 16 is a second assembling structure among a gas distribution rod, an inner cylinder and a 0 rear adapter of an embodiment of the invention.

Fig. 17 is a top view of a positioning shaft ring in the second assembling structure of the gas distribution rod of an embodiment of the invention.

Fig. 18 is integrated schematic structural diagram of a drill bit of an embodiment of the invention. 5 Fig. 19 is a right view of a drill bit of Fig. 18.

Fig. 20 is a B-B sectional view of the drill bit of Fig. 18.

Fig. 21 is a C-C sectional view of the drill bit of Fig. 19.

The following refemec numerals are usedin the drawings.: Rear adapter 1, check valve 2, spring 3, gas distribution rod 4, inner cylinder 5, piston 6, outer pipe sleeve 7, check ring 9, 20 guide sleeve 10, snap ring 11, front adapter 12 and drill bit 13.

Detailed Description of the Preferred Embodiments

Embodiments of the invention are further described hereinafter with reference to the drawings. 10

Embodiment 1: 2015282366 29 Dec 2015

See Fig. 1, the specific installation and connection mode in Fig. are as follows: a down-the-hole impacter includes a rear adapter 1, an outer pipe sleeve 7, a front adapter 12 and a drill bit 13, wherein the rear adapter 1 is connected to one end of the outer pipe sleeve 7, 5 the other end of the outer pipe sleeve 7 is connected to the front adapter 12, the drill bit 13 is installed inside the front adapter 12 through a snap ring 11, an inner cylinder 5 is installed in the outer pipe sleeve 7, a gas distribution rod 4 is installed in the cavity body of the inner cylinder 5, a check valve 2 is matched with a spring 3 to install in the inner cavity at the end portion of the gas distribution rod 4, a piston 6 is installed in the cavity body of the outer pipe 0 sleeve 7 and forms a sliding connection with the terminal of the piston 6, and the outer pipe sleeve 7 is provided with a retainer ring 9 for positioning a guide sleeve 10.

Embodiment 2:

See Fig. 2-1 to Fig. 10-3, the ratio of the total length of the piston 6 and the maximum outer diameter is less than 3.8, an unique center gas holes e is opened in the central position of the 5 piston 6, the small end of the piston 6 is equipped with a step a, the step a is in a sliding fit with the guiding sleeve 10, a guiding section f formed by a circular bead and a taper angle is machined in the impacting end face of the piston 6, the middle part of the piston 6 is equipped with a supporting section b matched with the inner hole of the outer pipe sleeve 7, the large end of the piston 6 is equipped with a large end step c, the large end step c is in a 20 sliding fit with the inner cylinder 5, a large end hole d forms a batch-type fit with the gas distribution rod 4 in the working process and is communicated with the center gas hole e.

Fig. 2-1 to Fig. 2-3, preferably, the outer edge of the left part portion of the supporting section b of the piston 6 is machined with a plurality of uniformly distributed third gas through grooves 28.1, the supporting section b close to the tail end of the third gas through groove 25 28.1 is machined with a third circular groove 32, the outer edge of the right half portion of the supporting section b is machined with a plurality of uniformly distributed fourth gas through grooves 33, a first circular groove 30 is machined close to the right side shaft diameter of the supporting section b, the outer edge of the right half portion of the large end step c is 11 machined with a plurality of uniformly distributed second gas through grooves 29, and the outer end face close to the large end hole d is machined with a circular recess j. 2015282366 29 Dec 2015

Fig. 3-1 to Fig. 3-3, preferably, the outer edge of the right half portion of the supporting section b of the piston 6 is machined with the plurality of uniformly distributed first gas 5 through grooves 28, the outer edge of the right half portion of the large end step c is machined with the plurality of second gas through grooves 29, and the outer end face close to the large end hole d is machined with the circular recess j. When the piston is adopted, the position of the recess matched with the supporting section b needs to be changed in the matching process with the outer pipe sleeve 7. 0 Fig. 4-1 to Fig. 4-3, preferably, the outer edge of the left half portion of the supporting section b of the piston 6 is machined with the plurality of uniformly distributed first gas through grooves 28, the outer edge of the right half portion of the large end step c is machined with the plurality of uniformly distributed second gas through grooves 29, the outer end face close to the large end hole d is machined with a circular recess j, the right side shaft diameter close 5 to the supporting section b is machined with the first circular groove 30, and the left side shaft diameter close to the large end step C is machined with a second circular groove 31.

Fig. 5-1 to Fig. 5-3, preferably, the outer edge of the left part portion of the supporting section b of the piston 6 is machined with the plurality of uniformly distributed third gas through grooves 28.1, the supporting section b close to the tail end of the third gas through groove 20 28.1 is machined with the third circular groove 32, the right side shaft diameter close to the supporting section b is machined with the first circular groove 30, the outer edge of the right half portion of the large end step c is machined with the plurality of uniformly distributed second gas through grooves 29, and the outer end face close to the large end hole d is machined with a circular recess j. 25 Fig. 6-1 to Fig. 6-3, preferably, the outer edge of the left half portion of the supporting section b of the piston 6 is machined with the plurality of uniformly distributed first gas through grooves 28, and the outer edge of the right half portion of the large end step c is machined with the plurality of second gas through grooves 29. When the piston is adopted, the position 12 of the recess matched with the supporting section b needs to be changed in the matching process with the outer pipe sleeve 7, so as to ensure the matching reliability. 2015282366 29 Dec 2015

Fig. 7-1 to Fig. 7-3, preferably, the outer edge of the right half portion of the supporting section b of the piston 6 is machined with the plurality of uniformly distributed first gas 5 through grooves 28, and the outer edge of the left half portion of the large end step c is machined with a plurality of uniformly distributed fifth gas through grooves 29.1.

Fig. 8-1 to Fig. 8-3, preferably, the outer edge of the right half portion of the supporting section b of the piston 6 is machined with the plurality of uniformly distributed first gas through grooves 28, the right side shaft diameter close to the supporting section b is 0 machined with the first circular groove 30, and the outer edge of the left half portion of the large end step c is machined with the plurality of uniformly distributed fifth gas through grooves 29.1.

Fig. 9-1 to Fig. 9-3, preferably, the outer edge of the left part portion of the supporting section b of the piston 6 is machined with the plurality of uniformly distributed third gas through 5 grooves 28.1, the supporting section b close to the tail end of the third gas through groove 28.1 is machined with the third circular groove 32, the right side shaft diameter close to the supporting section b is machined with the first circular groove 30, and the outer edge of the left half portion of the large end step c is machined with the plurality of uniformly distributed fifth gas through grooves 29.1. 20 Fig. 10-1 to Fig. 10-3, preferably, the outer edge of the left part portion of the supporting section b of the piston 6 is machined with a plurality of uniformly distributed third gas through grooves 28.1, the supporting section b close to the tail end of the third gas through groove 28.1 is machined with a third circular groove 32, the outer edge of the right half portion of the supporting section b is machined with a plurality of uniformly distributed 25 fourth gas through grooves 33, a first circular groove 30 is machined close to the right side shaft diameter of the supporting section b, the outer edge of the left half portion of the large end step c is machined with the plurality of uniformly distributed fifth gas through grooves 29.1. 13

Embodiment 3: 2015282366 29 Dec 2015

See Fig. 11 to Fig. 13, the snap ring 11 is in a subdivision-type structure, one end of the snap ring 11 matched with the drill bit 13 is internally machined with an inner step 11.1, the inner step 11.1 and the outer end face of the drill bit 13 form a sliding fit, the outer round face of 5 the snap ring 11 matched with the front adapter 12 is machined with a transition step 11.2, the end face of the snap ring 11 matched with the guide sleeve 10 is machined with an outer step 11.3, and the outer step 11.3 is matched with and positioned with the top end of the front adapter 12.The assembling and positioning precision of the snap ring 11 and the front adapter 12 can be improved through the transition step 11.2, thereby preventing displacement in the 0 work process to ensure the service life.At the same time, the service life of the drill bit 13 is prolonged.

See Fig. 12 to Fig. 13, the snap ring 11 is in the subdivision-type structure, one end of the snap ring 11 matched with the drill bit 13 is internally machined with the inner step 11.1, the inner step 11.1 and the outer end face of the drill bit 13 form the sliding fit, the end face of 5 the snap ring 11 matched with the guide sleeve 10 is machined with the outer step 11.3, and the outer step 11.3 is matched with and positioned with the top end of the front adapter 12.Adopting the single-step assembling mode can increase the contact area of the outer wall of the snap ring 11 and the front adapter 12, prolong the service life of the snap ring, prevent damage due to impact incurred and improve strength at the same time. In this way, it is more 20 convenient to assemble and disassemble the impacter; second, compared to the traditional design, the design of partly sinking the snap ring into the front adapter makes the structure more compact and reliable.

Embodiment 4:

See Fig. 14 to Fig. 15, the gas distribution rod 4 is equipped with a positioning shaft collar 23, 25 the positioning shaft collar 23 is installed inside the inner cylinder 5, the left end face of the positioning shaft collar 23 is matched and positioned through the inner shaft shoulder of the inner cylinder 5, the periphery of the positioning shaft collar 23 is machined with a plurality of uniformly distributed gas distribution rod gas through notches 23.1, and the right end face 14 of the positioning shaft ring 23 is matched with the left end face of the rear adapter 1 to press inside the inner cylinder 5. 2015282366 29 Dec 2015

See Fig. 16 to Fig. 17, the left end face of the positioning shaft ring 23 is matched with and positioned with the right end face of the inner cylinder 5, the positioning shaft collar 23 is 5 machined with a plurality of uniformly distributed gas distribution rod gas through notches 23.2, and the periphery of the positioning shaft collar 23 is matched with the inner wall of the outer pipe sleeve 7 and the right end face of the positioning shaft collar 23 is matched with and positioned with the left end face of the rear adapter 1.Adopting the above-mentioned positioning shaft collar 23 can effectively prolong the service life of the inner cylinder 5, the 0 inner cylinder 5 is prevented from being broken under an impact effect, so that the structural strength is ensured. At the same time, the stability of the gas distribution rod can be improve by adopting the above-mentioned structure.

Second, the gas distribution rod is uniformly distributed with a gas distribution rod gas through hole, it is not easy to cause deformation and breakage in working hours, a gas 5 distribution passage is simple and smooth so as to reduce the energy loss; and third, the matching portion of the gas distribution rod and the piston rod is equipped with a plurality of damping grooves, which can effectively reduce the leakage of the high-pressure air.

Embodiment 5:

See Fig. 18 to Fig. 21, the drill bit 13 comprises a steel body 13.1 and alloy teeth 13.2, the 20 front end portion of the steel body 13.1 is equipped with a non-spline type integrated cylinder impacting step 13.3 the impacting step 13.3 and the outer wall of the inner cavity of the snap ring 11 form a sliding fit, the middle part of the outer surface of the steel body 13.1 is equipped with a plurality of splines 13.4, the middle part of the drill bit is equipped with a drill bit center gas hole 13.5, the rear end of the steel body 13.1 is equipped with an inclined 25 gas hole 14, the drill bit center gas hole 13.5 is communicated with the inclined gas hole 14, the installing end face of the alloy teeth 13.2 is machined with a top portion powder discharging groove 13.6 communicated with the inclined gas hole 14, and the side face of the drill bit is machined with a side portion powder discharging groove 13.7 communicated with 15 the top portion powder discharging groove 13.6. 2015282366 29 Dec 2015

Through the distribution and use of a tailless pipe bit, the impacter adopts the guide sleeve to match with the piston to complete the gas distribution, the participation of the tailless pipe bit in the working process lowers the failure rate.The installing end face of the alloy teeth of 5 the drill bit is machined with a top portion powder discharging groove communicated with the inclined gas hole, the side face of the drill bit is machined with a side portion powder discharging groove communicated with the top portion powder discharging groove, so that it is convenient to discharge the chiseled rock powder through a gas discharging groove in a mode of gas outlet, the tail handle of the drill bit has short length and strong strength, thereby 0 effectively shortening the downtime due to the damage of the drill bit.

The operating principle of the invention is that, labeling the I-type piston for description:

When preparing for rock drilling operation, firstly, the drill bit of the impacter contacts with the rock, the impacter supports the piston 6 under the self-gravity to enable the impacter to be in an initial work state.

5 A check valve 2 is supported by the high-pressure gas P introduced by A hole duct 25 in A rear adapter 1, the high-pressure gas flows through a valve end gap 24, a side passage 23 of the gas distribution rod 4, a circular cavity 20 formed by the outer wall of an inner cylinder 5 and the inner wall of an outer pipe sleeve 7, and a gas groove 8 and a gas groove 19 formed on the outer surface of a piston 6; finally, the high-pressure gas alternatively enters into a 20 front gas chamber 17 and a rear gas chamber 21 of a gas cylinder.

When starting back tracking, the high-pressure gas in the circular cavity 20 enters into the front gas chamber 17 through the gas groove 8 and the gas groove 19 on the outer surface of the piston 6 to drive the piston 6 to move.In motion of back tracking of the piston 6, when the gas groove 8 of the piston 6 is closed, the gas inlet of the front gas chamber 17 stops, the 25 piston 6 continues to move upward by means of the high-pressure gas in the front gas chamber; after the impacting end of the piston 6 is separated from a guide sleeve 10, the gas in the front gas chamber 17 is discharged to the bottom of the hole through a drill bit center 16 hole 15 and an end face inclined hole 14.When the piston 6 starts the motion of back tracking, the gas P of the rear gas chamber 21 is escaped to the bottom of the hoe through a piston center gas hole 26, a drill bit center hole 15 and a drill bit inclined hole 14, so that the back pressure resistance suffered by the piston 6 in motion is very low; when the small head of the 5 air distribution rod 4 starts entering into the piston 6 to form a sealing fit, the gas of the rear gas chamber 21 is compressed by the motion of back tracking of the piston 6; when the large end of the piston 6 moves to the inner wall of the inner cylinder 5 to form an opening, the high-pressure gas enters into the rear gas chamber 21 through the gas groove 19 on the outer surface of the piston 6, the piston 6 will continue to slide a section of distance under the 0 inertia effect until the high-pressure gas entering into the rear gas chamber 21 generates a pressure to enable the piston 6 to stop the motion of back tracking. 2015282366 29 Dec 2015

In piston stroke, at the moment when the opening formed by the large end of the piston 6 and the circular cavity 27 in the inner cylinder 5 closes under the push of the high-pressure gas, the passage for the high-pressure gas to enter into the rear gas chamber 21 is closed, the 5 piston 6 moves forward through the gas expansion. After the piston center hole is separated from the lower end of the gas distribution rod, the gas in the rear gas chamber is discharged to the bottom of the hole through the piston center gas hole 26, the drill bit center hole 15 and the drill bit inclined hole 14.At this time, the piston 6 hits against the tail portion of the drill bit to complete the stroke motion. When the piston 6 starts the stroke motion, the gas of the 20 front gas chamber 17 continues to be discharged to the bottom of the hole through the guide sleeve, the drill bit center hole 15 and the drill bit inclined hole 14; when the piston 6 and the guide sleeve form a fit, the gas of the front gas chamber starts compression, the piston moves until communicating with the gas groove 19 on the surface of the piston, the high-pressure gas enters into the front gas chamber 17 to complete the gas distribution process. 25 The term “comprise” and variants of that term such as “comprises” or “comprising” are used herein to denote the inclusion of a stated integer or integers but not to exclude any other integer or any other integers, unless in the context or usage an exclusive interpretation of the term is required. 17

Reference to background art or other prior art in this specification is not an admission that such background art or other prior art is common general knowledge in Australia or elsewhere. 2015282366 29 Dec 2015 5 18

Claims (11)

1. A down-the-hole impacter, comprising a rear adapter, an outer pipe sleeve, a front adapter and a drill bit, wherein the rear adapter is connected to one end of the outer pipe sleeve, the other end of the outer pipe sleeve is connected to the front adapter, the drill bit is installed inside the front adapter through a snap ring, an inner cylinder is installed in the outer pipe sleeve, a gas distribution rod is installed in the cavity body of the inner cylinder, a check valve is matched with a spring to install in the inner cavity at the end portion of the gas distribution rod, a piston is installed in the cavity body of the outer pipe sleeve and forms a sliding connection with the terminal of the piston, and the outer pipe sleeve is provided with a retainer ring for positioning a guide sleeve; the ratio of the total length of the piston and the maximum outer diameter is less than 3.8, an unique center gas holes is opened in the central position of the piston, the small end of the piston is equipped with a step, the step is in a sliding fit with the guiding sleeve, a guiding section formed by a circular bead and a taper angle is machined in the impacting end face of the piston, the middle part of the piston is equipped with a supporting section matched with the inner hole of the outer pipe sleeve, the large end of the piston is equipped with a large end step, the large end step is in a sliding fit with the inner cylinder, a large end hole forms a batch-type fit with the gas distribution rod in the working process and is communicated with the center gas hole; the outer edge of the left part portion of the supporting section of the piston is machined with a plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with a third circular groove, the outer edge of the right half portion of the supporting section is machined with a plurality of uniformly distributed fourth gas through grooves, the right side shaft diameter close to the supporting section is machined with a first circular groove, the outer edge of the right half portion of the large end step is machined with a plurality of uniformly distributed second gas through grooves, and the outer end face close to the large end hole is machined with a circular recess; the snap ring is in a subdivision-type structure, one end of the snap ring matched with the drill bit is internally machined with an inner step, the inner step and the outer end face of the drill bit form a sliding fit, the outer round face of the snap ring matched with the front adapter is machined with a transition step, the end face of the snap ring matched with the guide sleeve is machined with an outer step, and the outer step is matched with and positioned with the top end of the front adapter; the gas distribution rod is equipped with a positioning shaft collar, the positioning shaft collar is installed inside the inner cylinder, the left end face of the positioning shaft collar is matched and positioned through the inner shaft shoulder of the inner cylinder, the periphery of the positioning shaft collar is machined with a plurality of uniformly distributed gas distribution rod gas through notches, and the right end face of the positioning shaft ring is matched with the left end face of the rear adapter to press inside the inner cylinder; the drill bit comprises a steel body and alloy teeth, the front end portion of the steel body is equipped with a non-spline type integrated cylinder impacting step the impacting step and the outer wall of the inner cavity of the snap ring form a sliding fit, the middle part of the outer surface of the steel body is equipped with a plurality of splines, the middle part of the drill bit is equipped with a drill bit center gas hole, the rear end of the steel body is equipped with an inclined gas hole, the drill bit center gas hole is communicated with the inclined gas hole, the installing end face of the alloy teeth is machined with a top portion powder discharging groove communicated with the inclined gas hole, and the side face of the drill bit is machined with a side portion powder discharging groove communicated with the top portion powder discharging groove.

2. The down-the-hole impacter according to claim 1, wherein the outer edge of the right half portion of the supporting section of the piston is machined with a plurality of uniformly distributed first gas through grooves, the outer edge of the right half portion of the large end step is machined with a plurality of uniformly distributed second gas through grooves, and the outer end face close to the large end hole is machined with the circular recess.

3. The down-the-hole impacter according to claim 1, wherein the outer edge of the left half portion of the supporting section of the piston is machined with the plurality of uniformly distributed first gas through grooves, the outer edge of the right half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves, the outer end face close to the large end hole is machined with the circular recess, the right side shaft diameter close to the supporting section is machined with the first circular groove, and the left side shaft diameter close to the large end step is machined with a second circular groove.

4. The down-the-hole impacter according to claim 1, wherein the outer edge of the left part portion of the supporting section of the piston is machined with the plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with the third circular groove, the right side shaft diameter close to the supporting section is machined with the first circular groove, the outer edge of the right half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves, and the outer end face close to the large end hole is machined with a circular recess.

5. The down-the-hole impacter according to claim 1, wherein the outer edge of the left half portion of the supporting section of the piston is machined with the plurality of uniformly distributed first gas through grooves, and the outer edge of the right half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves.

6. The down-the-hole impacter according to claim 1, wherein the outer edge of the right half portion of the supporting section of the piston is machined with the plurality of uniformly distributed first gas through grooves, and the outer edge of the left half portion of the large end step is machined with a plurality of uniformly distributed fifth gas through grooves.

7. The down-the-hole impacter according to claim 1, wherein the outer edge of the right half portion of the supporting section of the piston is machined with the plurality of uniformly distributed first gas through grooves, the right side shaft diameter close to the supporting section is machined with the first circular groove, and the outer edge of the left half portion of the large end step is machined with the plurality of uniformly distributed fifth gas through grooves.

8. The down-the-hole impacter according to claim 1, wherein the outer edge of the left part portion of the supporting section of the piston is machined with the plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with the third circular groove, the right side shaft diameter close to the supporting section is machined with the first circular groove, and the outer edge of the left half portion of the large end step is machined with the plurality of uniformly distributed fifth gas through grooves.

9. The down-the-hole impacter according to claim 1, wherein the outer edge of the left part portion of the supporting section of the piston is machined with the plurality of uniformly distributed third gas through grooves, the supporting section close to the tail end of the third gas through groove is machined with the third circular groove, the outer edge of the right half portion of the supporting section is machined with the plurality of uniformly distributed fourth gas through grooves, the right side shaft diameter close to the supporting section is machined with the first circular groove, the outer edge of the left half portion of the large end step is machined with the plurality of uniformly distributed second gas through grooves.

10. The down-the-hole impacter according to claim 1, wherein the snap ring is in the subdivision-type structure, one end of the snap ring matched with the drill bit is internally machined with the inner step, the inner step and the outer end face of the drill bit form the sliding fit, the end face of the snap ring matched with the guide sleeve is machined with the outer step, and the outer step is matched with and positioned with the top end of the front adapter.

11. The down-the-hole impacter according to claim 1, wherein the left end face of the positioning shaft ring is matched with and positioned with the right end face of the inner cylinder, the positioning shaft collar is machined with a plurality of uniformly distributed gas distribution rod gas through notches, and the periphery of the positioning shaft collar is matched with the inner wall of the outer pipe sleeve and the right end face of the positioning shaft collar is matched with and positioned with the left end face of the rear adapter.