CN118441988B - Positive cycle hydraulic impactor - Google Patents

Abstract

The present invention relates to the technical field of drilling impactors, and in particular to a positive circulation hydraulic impactor, wherein a valve member is provided on the upper body of the inner cylinder thereof, and is configured to be driven to perform vertical linear sliding based on the hydraulic pressure difference generated on the valve member itself, so as to cut off and open the connection between the liquid inlet flow path on the piston and the liquid inlet main flow channel, thereby realizing the axial movement of the impact piston. Since the valve member is switched in a linear sliding motion mode, this can be realized based on the pressure difference at both ends of the valve member of the hydraulic impactor, which solves the problem of rapid wear caused by the hydraulic pressure difference at both ends of the valve core of the central rotary valve hydraulic impactor, and significantly prolongs the service life of the impactor.

Description

Positive circulation hydraulic impactor

Technical Field

The invention relates to a hydraulic impactor for drilling, in particular to a positive circulation hydraulic impactor which is suitable for various drilling holes for fast drilling of hard rock.

Background

The core machine of the hydraulic impact rotary drilling technology is a hydraulic down-the-hole hammer, also called a hydraulic impactor. The technique has the advantages of long back-pass length, long service life of the drill bit, good drilling quality, less hole accidents, wide application range and the like. However, compared with the air down-the-hole hammer rotary drilling technology, the impact frequency and the average drilling speed of the hydraulic impactor are still slightly insufficient.

In the prior art, patent CN113585960A named as a central rotary valve type hydraulic impactor adopts a central rotary valve structure to realize high-frequency and high-speed movement of a hydraulic impactor piston, but because the upper cavity and the lower cavity of the central rotary valve are respectively positioned at a high-pressure end and a low-pressure end, the central rotary valve is subjected to unbalanced pressure, the central rotary valve has serious abrasion on the end face after being used for a period of time, and the phenomenon of blocking, discontinuous impact and the like of the rotary action of the central rotary valve is caused, so that the service life of the central rotary valve is shorter, and the engineering requirements cannot be met.

Therefore, it is necessary to design a novel hydraulic impactor which can effectively solve the above-mentioned problems of the central rotary valve type hydraulic impactor.

Disclosure of Invention

In view of the above, the present invention provides a valve-controlled high-energy high-frequency impactor, which uses high-pressure water as a pressure medium to provide a technical solution for high-efficiency drilling of hard rock, so as to solve the above-mentioned technical problems.

The invention discloses a positive circulation hydraulic impactor, which comprises an outer cylinder and an impact piston arranged in the outer cylinder, and also comprises an inner cylinder which is axially positioned and arranged in the outer cylinder, wherein the impact piston can be operated to axially reciprocate relative to the outer cylinder and the inner cylinder based on fluid liquid pressure difference, the impact piston is at least partially positioned in the inner cylinder, the inner cylinder comprises an upper body part and a lower body part which is axially abutted and matched with the upper body part, an upper piston section of the impact piston is received in a piston receiving cavity of the upper body part, a space between the upper end part of the impact piston and the bottom of the piston receiving cavity is formed into a piston upper liquid cavity, and a piston lower liquid cavity is formed between a lower piston section of the impact piston close to the bottom of the inner cylinder and the inner wall of the lower body part. The upper body part is provided with a piston upper liquid inlet flow path and a piston lower liquid inlet flow path, the piston upper liquid inlet flow path is always communicated with the piston upper liquid cavity for guiding fluid into the piston upper liquid cavity, the piston lower liquid inlet flow path is always communicated with the piston lower liquid cavity for guiding fluid into the piston lower liquid cavity, a liquid inlet total flow path is arranged between the outer side wall of the upper body part and the inner side wall of the outer cylinder, the piston lower liquid inlet flow path is always communicated with the liquid inlet total flow path, the upper body part is further provided with a valve component which is configured to be driven to vertically and linearly slide relative to the upper body part based on a liquid pressure difference generated on the valve component so as to cut off and open the communication between the piston upper liquid inlet flow path and the liquid inlet total flow path.

In the present invention, the terms "upper" and "lower" are relative terms based on the direction of penetration of the bit body, i.e., a position toward or near the direction of penetration of the bit body may be designated as downward and a position away from or away from the direction of penetration of the bit body may be designated as upward.

Since the valve member is configured to be able to slide linearly on the basis of the axial movement of the impact piston, this is achieved by means of the hydraulic pressure difference that must be created during operation of the hydraulic impactor. Therefore, the quick abrasion problem caused by the fact that the central rotary valve type hydraulic impactor is not suitable for hydraulic pressure difference at two ends of the valve core is solved, and the service life of the impactor is remarkably prolonged.

According to the positive-cycle hydraulic impactor disclosed by the invention, in the initial state of the impactor, the valve member is positioned at the initial position of the impactor, at the moment, the communication between the liquid inlet flow path on the piston and the liquid inlet main flow path is cut off, and the communication between the liquid inlet flow path on the piston and the liquid inlet main flow path can be opened in the process that the valve member is driven to linearly slide vertically downwards relative to the upper body part on the basis of the liquid pressure difference generated on the valve member.

That is, the valve member has an initial position, which is a position of the valve member in an initial state of the impactor, in which the valve member cuts off communication of the plunger feed liquid flow path with the feed liquid flow path, and a communication position, which is located below the initial position, from which the valve member can be urged to move downward based on the liquid pressure difference, to the communication position, and when the valve member moves to the communication position, it can open communication of the plunger feed liquid flow path with the feed liquid flow path, so that high-pressure liquid can enter from the feed liquid flow path into the plunger feed liquid flow path, and thus into the plunger feed liquid chamber.

The positive circulation hydraulic impactor disclosed by the invention is further provided with a valve upper liquid cavity, a valve lower liquid inlet flow channel and a valve upper liquid inlet flow channel on the upper body part, wherein the valve lower liquid inlet flow channel is always communicated with the valve lower liquid cavity for guiding fluid into the valve lower liquid cavity, the valve upper liquid inlet flow channel is always communicated with the valve upper liquid cavity for guiding fluid into the valve upper liquid cavity, the valve lower liquid inlet flow channel is always communicated with the liquid inlet main flow channel, and the valve lower liquid inlet flow channel can be communicated with and disconnected from the piston upper liquid inlet flow channel by means of linear sliding of a valve member so as to realize the communication and disconnection between the piston upper liquid inlet flow channel and the liquid inlet main flow channel.

According to the positive circulation hydraulic impactor disclosed by the invention, an internal pressure relief channel is formed in the impact piston, the valve upper liquid inlet channel is communicated with the internal pressure relief channel by switching between the lower liquid inlet channel and the internal pressure relief channel by means of axial movement of the impact piston, in an initial state, the valve upper liquid inlet channel is communicated with the lower liquid inlet channel, the valve upper liquid inlet channel is disconnected from the internal pressure relief channel, and in the process that the impact piston is driven to move upwards by the hydraulic pressure difference between the lower liquid cavity and the upper liquid cavity of the piston, the valve upper liquid inlet channel can be communicated with the internal pressure relief channel of the piston, so that the valve member is depressurized, and the valve upper liquid inlet channel is disconnected from the lower liquid inlet channel.

The positive circulation hydraulic impactor disclosed by the invention further comprises a mandrel, wherein the mandrel is sleeved in the upper piston section of the impact piston in a close fitting manner, a pressure relief transition channel which is always communicated with a pressure relief channel in the piston is formed in the mandrel, a pressure relief communication hole is formed in the side wall of the mandrel, a valve pressure relief hole is formed in the side wall of the upper piston section of the impact piston, the valve pressure relief hole is disconnected from the pressure relief communication hole in an initial state of the impactor, and when the impact piston moves upwards to the state that the valve pressure relief hole is communicated with the pressure relief communication hole, a valve liquid inlet channel is communicated with the pressure relief transition channel and the pressure relief channel in the piston.

The positive circulation hydraulic impactor disclosed by the invention is characterized in that a valve inner pressure relief channel is arranged in the valve member and is always communicated with the pressure relief transition channel, a piston pressure relief hole is formed in the side wall of the lower part of the valve member, the piston pressure relief hole is communicated with a piston upper liquid inlet flow channel in the initial state of the impactor, and the piston pressure relief hole can be disconnected with the piston upper liquid inlet flow channel in the process that the valve member is driven to linearly slide vertically downwards relative to the upper body part based on the liquid pressure difference generated on the valve member, and the piston upper liquid inlet flow channel is communicated with a valve lower liquid inlet flow channel.

The positive-cycle hydraulic impactor disclosed by the invention is characterized in that a groove is formed on the upper piston section of the impact piston at the position corresponding to the pressure relief hole of the valve, a gap is formed between the groove and the inner wall of the upper body part so as to form a groove flow channel, in an initial state, the valve upper liquid inlet flow channel is communicated with the piston lower liquid inlet flow channel by means of the groove flow channel, and the side wall of the upper piston section below the groove is configured to be tightly matched with the inner wall of the upper body part so as to disconnect the communication between the groove flow channel and the piston lower liquid inlet flow channel during the upward movement of the impact piston.

The positive-cycle hydraulic impactor according to the invention, wherein the inner part of the outer cylinder is provided with a radially inwardly protruding flange, the inner cylinder further comprises a sealing sleeve, the sealing sleeve is abutted against the flange in an axially positioned manner, the lower end of the impact piston protrudes from the sealing sleeve, the bottom of the lower body is supported on the top of the sealing sleeve, the lower body is in close fit with the inner wall of the outer cylinder, and the bottom of the upper body is supported on the top of the lower body.

The positive circulation hydraulic impactor disclosed by the invention further comprises an upper end cover which is abutted against the top of the upper body, wherein the upper end cover and the end part of the upper body jointly enclose a valve upper liquid cavity, and the upper end of the valve member is abutted against the bottom of the upper end cover in an initial state.

The positive circulation hydraulic impactor disclosed by the invention further comprises a liquid inlet joint attached to the liquid inlet end of the outer cylinder and a flow guide member arranged in the liquid inlet joint, wherein the lower end of the flow guide member is abutted against the upper end cover in an end blocking manner, and the upper end of the flow guide member is axially pressed by means of a step structure in the liquid inlet joint, so that the flow guide member and the inner cylinder are axially fixed in the outer cylinder.

The positive circulation hydraulic impactor disclosed by the invention has the advantages that a gap is formed between the flow guiding component and the liquid inlet joint so as to form a liquid inlet initial flow passage, and the liquid inlet initial flow passage is communicated with the liquid inlet of the liquid inlet joint.

The positive circulation hydraulic impactor has the beneficial effects that the valve member is arranged in the inner cylinder of the positive circulation hydraulic impactor, and the valve member is configured to be driven to perform vertical linear sliding based on the hydraulic pressure difference generated on the valve member, so that the positive circulation hydraulic impactor can be realized based on the hydraulic pressure difference generated in the working process of the hydraulic impactor, thereby solving the problem that the central rotary valve type hydraulic impactor is not suitable for rapid abrasion caused by the hydraulic pressure difference at two ends of the valve core, and remarkably prolonging the service life of the impactor.

The positive cycle hydraulic impactor of the present invention is disclosed in detail below in connection with the embodiments shown in the drawings and the reference numerals.

Drawings

Fig. 1 shows a schematic view of the overall structure of the positive-cycle hydraulic impactor of the present invention, which is in an initial state.

Fig. 2 is an enlarged view at a in fig. 1.

Reference numerals

The device comprises an outer cylinder 1, an impact piston 2, an upper body part 3, a lower body part 4, a piston upper liquid cavity 5, a piston lower liquid cavity 6, a piston upper liquid inlet channel 7, a piston lower liquid inlet port 8a, a piston lower liquid inlet channel 8b, a liquid inlet main channel 9, a valve member 10, a valve upper liquid cavity 11, a valve lower liquid cavity 12, a valve lower liquid inlet channel 13, a valve upper liquid inlet channel 14, a valve upper liquid flow channel 14a, a valve upper liquid flow channel opening 15, a piston inner pressure relief channel 16, a core shaft 17 pressure relief transition channel, a pressure relief communication hole 18, a valve pressure relief hole 19, a valve inner pressure relief channel 20, a piston pressure relief hole 21, a groove flow channel 22, a flange 23, a sealing sleeve 24, an upper end cover 25, a liquid inlet joint 26, a flow guide member 27, a liquid inlet initial flow channel 28, a liquid inlet port 29, a bit body 30, a spline sleeve 31, a 32 retaining ring, a limit sleeve 33, a bit inner channel 34, a flow outlet channel 35 and a sealing gasket 36.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other.

Fig. 1 shows a schematic view of the overall structure of the positive-cycle hydraulic impactor of the present invention, which is in an initial state. Fig. 2 is an enlarged view at a in fig. 1.

As shown in connection with fig. 1 and 2, the impactor of the present invention comprises a liquid inlet joint 26, an outer cylinder 1, an inner cylinder, an impact piston 2, a spline housing 31 and a bit body 30, as well as a flow guiding member 27 and a valve member 10. The liquid inlet joint 26 is connected with the outer cylinder 1 through matched threads, and the inner cylinder comprises an upper body 3, a lower body 4 and a sealing sleeve 24 which is connected with the lower body 4 and axially positioned on the inner wall of the outer cylinder 1. The upper body 3, the lower body 4 and the sealing sleeve 24 are sequentially and axially arranged in the outer cylinder 1, the axial position is fixed with a step on the outer cylinder 1 through a liquid inlet joint 26, the impact piston 2 is arranged in the inner cylinder through sliding fit, and the lower end of the impact piston extends out from the sealing sleeve 24. The whole inner cylinder is fixed in axial position by the flow guiding member 27 and the liquid inlet joint 26. The valve member 10 is fitted in the upper body 3 of the inner cylinder and is restrained in its axially movable position by an upper end cap, and the spline housing 31 is screwed to the outer cylinder 1.

In addition, the impactor of the invention can further comprise a retaining ring 32 and a limiting bushing 33, wherein the lower end of the outer cylinder 1 is connected with the spline sleeve 31 through threads, the spline on the bit body 30 is matched with the spline groove on the spline sleeve 31, the retaining ring 32 is clamped in the annular groove on the upper part of the spline of the bit body 30 and is blocked on the top surface of the spline sleeve 31, the bit body 30 is prevented from falling off from the spline sleeve 31, the retaining ring 32 is in a semicircular clamp in the preferred embodiment, the upper top surface of the limiting bushing is sleeved on the periphery of the upper part of the bit body 30, and the upper top surface of the limiting bushing is abutted against the limiting step on the inner wall of the outer cylinder 1, and the lower bottom surface of the limiting bushing is pressed on the retaining ring 32 to limit the retaining ring 32. Of course, it will also be appreciated by those skilled in the art that the bit body 30 can be mounted to the end of the outer cylinder 1 of the impactor by any other known attachment structure, provided that the drilling operation is effected when the bit body 30 is impacted by the impact piston 2.

In an embodiment of the invention, the positive-cycle hydraulic impactor comprises an outer cylinder 1 and an impact piston 2 arranged in the outer cylinder 1, and further comprises an inner cylinder which is axially positioned inside the outer cylinder 1, the impact piston 2 being operable to perform an axial reciprocating movement relative to the outer cylinder 1 and the inner cylinder based on a fluid pressure difference, the impact piston 2 being at least partly located in the inner cylinder, the inner cylinder comprising an upper body 3 and a lower body 4 in axial abutting engagement with the upper body 3, an upper piston section of the impact piston 2 being received in a piston receiving chamber of the upper body 3, and a space between an upper end of the impact piston 2 and a bottom of the piston receiving chamber forming a piston top chamber 5, a piston bottom chamber 6 being formed between a lower piston section of the impact piston 2 near the bottom of the inner cylinder and an inner wall of the lower body 4. Wherein the upper body part 3 is provided with a piston upper liquid inlet flow path 7 and a piston lower liquid inlet flow path, and the piston lower liquid inlet flow path comprises a piston lower liquid inlet port 8a and a piston lower liquid inlet flow path 8b. In one particular embodiment, the piston lower liquid inlet 8a is formed by an opening on the lower side of the upper body, while the piston lower liquid inlet channel 8b is formed by a gap between the impact piston 2 and the lower body 4.

Specifically, the piston upper liquid inlet flow path 7 is kept in constant communication with the piston upper liquid chamber 5 for introducing the fluid into the piston upper liquid chamber 5, the piston lower liquid inlet flow path is kept in constant communication with the piston lower liquid chamber 6 for introducing the fluid into the piston lower liquid chamber 6, a liquid inlet total flow path 9 is provided between the outer side wall of the upper body portion 3 and the inner side wall of the outer cylinder 1, wherein a piston lower liquid inlet port 8a in the piston lower liquid inlet flow path is kept in constant communication with the liquid inlet total flow path 9, and a valve member 10 is further provided on the upper body portion 3 and is configured to be capable of being driven to perform vertical linear sliding relative to the upper body portion 3 based on a liquid pressure difference generated on itself to cut off and open the communication between the piston upper liquid inlet flow path 7 and the liquid inlet total flow path 9.

Since the valve member 10 is configured to be able to produce a linear sliding movement based on the axial movement of the impact piston 2, this is made possible by means of the hydraulic pressure difference that must be created during operation of the hydraulic impactor. Therefore, the quick abrasion problem caused by the fact that the central rotary valve type hydraulic impactor is not suitable for hydraulic pressure difference at two ends of the valve core is solved, and the service life of the impactor is remarkably prolonged.

In the embodiment of the present invention in which the valve member 10 is in its initial position in the initial state of the impactor, at which time the communication of the piston-on-fluid intake passage 7 with the intake manifold 9 is cut off, the communication of the piston-on-fluid intake passage 7 with the intake manifold 9 can be opened during the time that the valve member 10 is driven to slide linearly vertically downward with respect to the upper body 3 based on the differential pressure generated on itself.

Namely, the valve member 10 has an initial position, which is a position of the valve member 10 in an initial state of the impactor, in which position the valve member 10 shuts off the communication of the piston upper feed passage 7 with the inlet manifold 9, and a communication position, which is located below the initial position, the valve member 10 being able to be urged to move downward based on the hydraulic pressure difference so as to move from the initial position to the communication position, and when the valve member 10 moves to the communication position, it is able to open the communication of the piston upper feed passage 7 with the inlet manifold 9 so that high-pressure liquid can enter from the inlet manifold 9 into the piston upper feed passage 7 so as to enter into the piston upper feed chamber 5.

In an embodiment of the invention, wherein the upper body part 3 is further provided with an upper valve liquid chamber 11, a lower valve liquid chamber 12, a lower valve liquid inlet flow passage 13 and an upper valve liquid inlet flow passage 14, wherein the lower valve liquid inlet flow passage 13 is kept in constant communication with the lower valve liquid chamber 12 for introducing fluid into the lower valve liquid chamber 12, the upper valve liquid inlet flow passage 14 is provided with an upper valve liquid flow passage 14a, the upper valve liquid inlet flow passage 14 is kept in constant communication with the upper valve liquid chamber 11 for introducing fluid into the upper valve liquid chamber 11, wherein the lower valve liquid inlet flow passage 13 is kept in constant communication with the inlet liquid main flow passage 9, and by means of linear sliding of the valve member 10, the lower valve liquid inlet flow passage 13 can be made in and out of communication with the upper piston liquid inlet flow passage 7 for realizing the communication and the disconnection of the upper piston liquid inlet flow passage 7 with the inlet liquid main flow passage 9.

In the embodiment of the invention, an in-piston pressure relief channel 15 is formed in the impact piston 2, a valve upper liquid inlet 14a of a valve upper liquid inlet channel 14 is switched to be communicated between a piston lower liquid inlet 8a of a piston lower liquid inlet channel and the in-piston pressure relief channel 15 by means of axial movement of the impact piston 2, in an initial state, the valve upper liquid inlet channel 14 is communicated with the piston lower liquid inlet channel, and the valve upper liquid inlet channel 14 is disconnected from the in-piston pressure relief channel 15, and in the process that the impact piston 2 is driven to move upwards due to the hydraulic difference between the piston lower liquid cavity 6 and the piston upper liquid cavity 5, the valve upper liquid inlet channel 14 can be communicated with the in-piston pressure relief channel 15, so that the valve member 10 is depressurized, and the valve upper liquid inlet channel 14 is disconnected from the piston lower liquid inlet channel.

In the embodiment of the invention, the impactor further comprises a mandrel 16 which is sleeved in the upper piston section of the impact piston 2 in a close fitting manner, a pressure relief transition channel 17 which is always communicated with the pressure relief channel 15 in the piston is formed in the mandrel 16, a pressure relief communication hole 18 is formed in the side wall of the mandrel 16, a valve pressure relief hole 19 is formed in the side wall of the upper piston section of the impact piston 2, the valve pressure relief hole 19 is disconnected from the pressure relief communication hole 18 in the initial state of the impactor, and when the impact piston 2 moves upwards until the valve pressure relief hole 19 is communicated with the pressure relief communication hole 18, the valve feed liquid flow channel 14 is communicated with the pressure relief transition channel 17 and the pressure relief channel 15 in the piston.

In the embodiment of the invention in which the valve member 10 has an internal relief passage 20 in constant communication with the relief transition passage 17, a piston relief orifice 21 is provided in the lower side wall of the valve member 10, which is in communication with the piston upper liquid inlet flow passage 7 in the initial state of the impactor, and the piston relief orifice 21 is capable of disconnecting from communication with the piston upper liquid inlet flow passage 7 when the piston upper liquid inlet flow passage 7 is in communication with the valve lower liquid inlet flow passage 13 during the valve member 10 being urged to slide linearly vertically downward relative to the upper body 3 based on the liquid pressure differential generated on itself.

Based on the above-described structure, in the present invention, the pressure relief of the valve member 10 and the pressure relief of the piston upper chamber 5 can share the same pressure relief passage, that is, the same pressure relief passage formed by the intra-valve pressure relief passage 20, the pressure relief transition passage 17, and the intra-piston pressure relief passage 15 together. The arrangement of the pressure relief channels is greatly simplified, and a plurality of pressure relief channels are not needed to be additionally arranged, so that the slotting of the inner cylinder is reduced, and the service life of the whole impactor is further prolonged.

In addition, the same pressure relief passage in common also includes an intra-bit passage 34 and an outflow passage 35.

In a preferred embodiment, the upper body 3 of the inner cylinder has its own mounting cavity penetrating down to the piston receiving cavity, which are formed from top to bottom as an upper valve liquid cavity 11, an upper valve mating cavity, a lower valve liquid cavity 12, a liquid inlet cavity of the upper piston liquid inlet flow channel 7 and a lower valve receiving cavity, respectively. Wherein the lower part of the valve member 10 passes through the feed chamber of the piston feed liquid flow channel 7 and is inserted into the valve lower receiving chamber, and the valve member 10 is in constant communication with the pressure relief transition channel 17 of the spindle 16 by means of the valve lower receiving chamber, wherein the radial cross-sectional width of the feed liquid chamber of the piston feed liquid flow channel 7 is larger than the lower cross-sectional width of the valve member 10, so that in an initial state it is possible to communicate with the piston pressure relief hole 21 in the valve member 10. The upper portion of the valve member 10 is located in the valve upper mating chamber and the middle portion of the valve member 10 is a constricted concave waist portion that corresponds to the position of the valve drainage chamber 12.

In the embodiment of the present invention, a groove is formed in the upper piston section of the impact piston 2 at a position corresponding to the valve relief hole 19 with a gap between the groove and the inner wall of the upper body 3 to form a groove flow passage 22, the valve upper liquid inlet flow passage 14 communicates with the piston lower liquid inlet flow passage by means of the groove flow passage 22 in the initial state, and the side wall of the upper piston section located below the groove is configured to be capable of forming a tight fit with the inner wall of the upper body 3 to disconnect the communication of the groove flow passage 22 with the piston lower liquid inlet flow passage during the upward movement of the impact piston 2.

In the embodiment of the invention in which the inner part of the outer cylinder 1 has a radially inwardly projecting flange 23, the inner cylinder further comprises a sealing sleeve 24, the sealing sleeve 24 resting in an axially positioned manner against the flange 23, the lower end of the impulse piston 2 projecting from the sealing sleeve 24, the bottom of the lower body 4 resting on top of the sealing sleeve 24 and the lower body 4 fitting snugly against the inner wall of the outer cylinder 1, the bottom of the upper body 3 resting on top of the lower body 4.

In the embodiment of the invention in which the inner cylinder further comprises an upper end cap 25 resting on top of the upper body 3, a sealing gasket 36 is provided between the bottom of the upper end cap and the top of the upper body in a preferred embodiment. In addition, the upper end cover 25 and the end of the upper body 3 together define a valve upper liquid chamber 11, and in the initial state, the upper end of the valve member 10 abuts against the bottom of the upper end cover 25.

In the embodiment of the invention in which the impactor further comprises a liquid inlet joint 26 attached to the liquid inlet end of the outer cylinder 1 and a flow guiding member 27 arranged in the liquid inlet joint 26, the lower end of the flow guiding member 27 abuts against the upper end cover 25 in an end-sealing manner, the upper end of the flow guiding member 27 is axially compressed by means of a stepped structure inside the liquid inlet joint 26, so that the flow guiding member 27 and the inner cylinder are axially fixed in the outer cylinder 1.

In the embodiment of the invention, a gap is formed between the flow guiding member 27 and the liquid inlet joint 26 to form a liquid inlet initial flow channel 28, and the liquid inlet 29 of the liquid inlet joint 26 and the liquid inlet main flow channel 9 are communicated. In a preferred embodiment, the flow directing member 27 is a filter with a filter aperture disposed therein that communicates the inlet initial flow passage 28 with the interior cavity of the filter.

The working principle of the impactor is that high-pressure liquid enters an initial liquid inlet flow passage 28 from a liquid inlet 29 through a flow guide member 27 in an initial state and sequentially passes through a liquid inlet main flow passage 9, a liquid inlet under piston 298a and a liquid inlet under piston 8b to enter a liquid under piston cavity 6, at the moment, the upper piston cavity 5 is communicated with an inner valve pressure relief channel 20 and an inner piston pressure relief channel 15 due to the fact that the upper piston cavity is communicated with the piston pressure relief hole 21, so that the upper piston cavity 5 is in a pressing state, and at the moment, the downward acting cross section area of the high-pressure liquid in the lower piston cavity and the liquid inlet under piston flow passage 8b is smaller than the upward acting cross section area, so that a pressure difference capable of pushing the impact piston 2 to move upwards is generated, and the impact piston 2 is pushed to move upwards under the pressure difference.

At the same time, the high-pressure liquid enters the valve lower liquid cavity 12 through the liquid inlet main flow channel 9 and the valve lower liquid inlet flow channel 13, and the piston lower liquid inlet 298a, the valve upper liquid flow channel 14a and the valve upper liquid inlet flow channel 14 enter the valve upper liquid cavity 11, at this time, the downward acting cross-sectional area of the high-pressure liquid in the valve member 10 and the valve lower liquid cavity 12 is larger than the upward acting cross-sectional area, so that a pressure difference capable of pushing the valve member 10 to move downward is generated, and the valve member 10 is pushed to move downward under the pressure difference.

At this time, the valve member 10 has moved downwards for a certain stroke, when the valve member 10 moves to the valve lower liquid chamber 12 and is communicated with the piston upper liquid inlet flow path 7, high-pressure liquid enters the piston upper liquid chamber 5 from the liquid inlet main flow path 9, the valve lower liquid inlet flow path 13, the valve lower liquid chamber 12 and the piston upper liquid inlet flow path 7, and at this time, the downward acting stress cross section of the high-pressure liquid in the upper liquid chamber is larger than the upward acting stress cross section of the high-pressure liquid in the lower liquid chamber, so that a pressure difference capable of pushing the impact piston 2 to move downwards is generated, and under the action of the pressure difference, the impact piston 2 can be pushed to be decelerated upwards and accelerated downwards to impact the bit body 30.

Wherein the valve member 10 has a relief passage for assisting its return, specifically, when the impact piston 2 moves up to a certain stroke, specifically, when the valve relief hole 19 and the relief communication hole 18 are brought into communication, the communication between the piston lower liquid inlet 298a and the valve upper liquid flow port 14a is closed, and the valve upper liquid flow port 14a and the valve relief hole 19 and the relief communication hole 18 are brought into communication, so that the valve upper liquid inlet flow passage 14 and the relief transition passage 17 and the piston inner relief passage 15 are brought into communication, thereby allowing the valve member 10 to complete the relief. At this time, the pressure difference between the valve top chamber 11 and the valve bottom chamber 12 pushes the valve member 10 upward until the valve member 10 returns to the original position, thereby completing one cycle of the movement of the impact piston 2 and the valve member 10.

The above process is repeated, so that the hydraulic positive circulation impactor impact drilling can be realized.

Spatially relative terms, such as "above," "upper" and "upper surface," "above" and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the process is carried out, the exemplary term "above" may be included. Upper and lower. Two orientations below. The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that embodiments of the application described herein may be capable of being practiced otherwise than as specifically illustrated and described. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Finally, it is noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the technical solution of the present invention, which is intended to be covered by the scope of the claims of the present invention.

Claims (10)

1. A positive-cycle hydraulic impactor comprising an outer cylinder, an impact piston arranged in the outer cylinder and an axially positioned inner cylinder arranged in the outer cylinder, the impact piston being operable to perform an axial reciprocating movement relative to the outer cylinder and the inner cylinder based on a fluid pressure difference, characterized in that,

The impact piston is at least partially positioned in the inner cylinder, the inner cylinder comprises an upper body part and a lower body part which is in axial abutting fit with the upper body part, an upper piston section of the impact piston is received in a piston receiving cavity of the upper body part, and a space between the upper end part of the impact piston and the bottom of the piston receiving cavity forms an upper liquid cavity;

The upper body part is provided with:

a piston upper fluid inlet flow path in constant communication with the piston upper fluid chamber for introducing fluid into the piston upper fluid chamber;

a piston lower liquid inlet flow path which is in constant communication with the piston lower liquid cavity and is used for guiding fluid into the piston lower liquid cavity;

a liquid inlet total flow passage is arranged between the outer side wall of the upper body part and the inner side wall of the outer cylinder, wherein a liquid inlet flow passage under the piston is always communicated with the liquid inlet total flow passage;

The upper body is also provided with a valve member which is configured to be capable of being driven to perform vertical linear sliding relative to the upper body based on a hydraulic pressure difference generated on the valve member so as to cut off and open communication between the plunger liquid inlet flow path and the liquid inlet total flow path;

The upper body part is also provided with a valve upper liquid cavity, a valve lower liquid inlet flow passage which is communicated with the valve lower liquid cavity normally and used for guiding fluid into the valve lower liquid cavity, and a valve upper liquid inlet flow passage which is communicated with the valve upper liquid cavity normally and used for guiding fluid into the valve upper liquid cavity, wherein the valve lower liquid inlet flow passage is communicated with the liquid inlet main flow passage normally, and by means of linear sliding of the valve member, the valve lower liquid inlet flow passage can be communicated with and disconnected from the piston upper liquid inlet flow passage so as to realize the communication and disconnection between the piston upper liquid inlet flow passage and the liquid inlet main flow passage.

2. The positive-working hydraulic impactor of claim 1, wherein,

In the initial state of the impactor, the valve member is located at the initial position, at this time, the communication between the liquid inlet flow path and the liquid inlet main flow path of the piston is cut off, and the communication between the liquid inlet flow path and the liquid inlet main flow path of the piston can be opened in the process that the valve member is driven to linearly slide vertically downwards relative to the upper body part based on the liquid pressure difference generated on the valve member.

3. The positive-working hydraulic impactor of claim 2, wherein,

The internal pressure release channel of the piston is formed in the impact piston, and the valve upper liquid inlet channel is communicated with the piston lower liquid inlet channel in a switching way by virtue of the axial movement of the impact piston;

In the initial state, the valve upper liquid inlet flow channel is communicated with the piston lower liquid inlet flow channel, and the valve upper liquid inlet flow channel is disconnected from the piston inner pressure release channel, and in the process that the impact piston is driven to move upwards due to the hydraulic difference between the piston lower liquid cavity and the piston upper liquid cavity, the valve upper liquid inlet flow channel can be communicated with the piston inner pressure release channel, so that the valve member is subjected to pressure release, and the valve upper liquid inlet flow channel is disconnected from the piston lower liquid inlet flow channel.

4. A positive-working hydraulic impactor according to claim 3, wherein,

The impactor further comprises a mandrel, wherein the mandrel is sleeved in the upper piston section of the impact piston in a close fitting mode, a pressure relief transition channel which is always communicated with a pressure relief channel in the piston is formed in the mandrel, and a pressure relief communication hole is formed in the side wall of the mandrel;

The side wall of the upper piston section of the impact piston is provided with a valve pressure relief hole, the valve pressure relief hole is disconnected from the pressure relief communication hole in the initial state of the impact piston, and when the impact piston moves upwards until the valve pressure relief hole is communicated with the pressure relief communication hole, a valve upper liquid inlet flow passage is communicated with the pressure relief transition passage and the pressure relief passage in the piston.

5. The positive-working hydraulic impactor of claim 4, wherein,

The interior of the valve member has an in-valve pressure relief passage in constant communication with the pressure relief transition passage;

The piston pressure relief hole is formed in the side wall of the lower portion of the valve member, the piston pressure relief hole is communicated with the upper liquid inlet flow channel of the piston in the initial state of the impactor, and the piston pressure relief hole can be disconnected from the upper liquid inlet flow channel of the piston in the process that the valve member is driven to vertically and downwards linearly slide relative to the upper body part on the basis of the liquid pressure difference generated on the valve member, and the upper liquid inlet flow channel of the piston is communicated with the lower liquid inlet flow channel of the valve.

6. The positive-working hydraulic impactor of claim 5, wherein,

A groove is formed on the upper piston section of the impact piston at a position corresponding to the valve pressure relief hole, and a gap is formed between the groove and the inner wall of the upper body part so as to form a groove flow passage;

In an initial state, the valve upper liquid inlet flow channel is communicated with the piston lower liquid inlet flow channel by the groove flow channel, and the side wall of the upper piston section below the groove is constructed to form close fit with the inner wall of the upper body part so as to disconnect the groove flow channel from the piston lower liquid inlet flow channel in the upward movement process of the impact piston.

7. The positive-working hydraulic impactor of claim 6, wherein,

The inner cylinder further comprises a sealing sleeve, the sealing sleeve is abutted against the flange in an axial positioning mode, and the lower end of the impact piston extends out of the sealing sleeve;

the bottom of the lower body is supported on the top of the sealing sleeve, the lower body is in close fit with the inner wall of the outer cylinder, and the bottom of the upper body is supported on the top of the lower body.

8. The positive-working hydraulic impactor of claim 7, wherein,

The inner cylinder further comprises an upper end cover propped against the top of the upper body part, the upper end cover and the end part of the upper body part jointly enclose the valve upper liquid cavity, and in an initial state, the upper end of the valve member is propped against the bottom of the upper end cover.

9. The positive-working hydraulic impactor of claim 8, wherein,

The impactor further comprises a liquid inlet connector attached to the liquid inlet end of the outer cylinder and a flow guide member arranged in the liquid inlet connector, wherein the lower end of the flow guide member abuts against the upper end cover in an end sealing manner, and the upper end of the flow guide member is axially pressed by means of a step structure in the liquid inlet connector, so that the flow guide member and the inner cylinder are axially fixed in the outer cylinder.

10. The positive-working hydraulic impactor of claim 9, wherein,

And a gap is formed between the flow guiding component and the liquid inlet joint so as to form a liquid inlet initial flow channel, and the liquid inlet initial flow channel is communicated with the liquid inlet joint and the liquid inlet total flow channel.