CN220929271U - Impact structure and rock drill - Google Patents

Abstract

The application provides an impact structure and a rock drill, wherein the impact structure comprises a piston, a cylinder sleeve component and an oil distributing valve, and the piston and the oil distributing valve are coaxially arranged in the cylinder sleeve component; the impact mechanism further comprises a piston front cavity and a piston rear cavity, the cylinder sleeve assembly is provided with an oil path channel communicated with the piston front cavity and the piston rear cavity, and the piston front cavity always keeps oil inlet; the oil distributing valve sleeve is arranged on the piston, and the oil distributing valve can do reciprocating motion along the axial direction of the piston so as to be used for changing the communication relation between the piston and the oil path channel, thereby assisting the reversing of the piston. The oil distributing valve of the impact structure is a sleeve valve type, so that the oil way can be effectively reduced, and the length of a piston can be shortened; the action surface of the oil distributing valve is larger, so that the reversing efficiency of the oil distributing valve is high, and the auxiliary reversing action on the piston is facilitated; the rock drill comprises the impact structure, the piston of the rock drill is short, the whole structure of the rock drill is compact, the size is small, and the impact efficiency is high.

Description

Impact structure and rock drill

Technical Field

The application relates to the technical field of rock drills, in particular to an impact structure and a rock drill.

Background

Rock drill is a tool for rock production and mainly comprises an impact structure and a turning structure. The rotary structure comprises a drill rod, the drill rod is impacted when the impact piston extends outwards from the cylinder body to the limit position, and the drill rod transmits impact force to rock for drilling.

In the impact structure, the impact structure generally comprises a cylinder sleeve, a piston and a reversing valve, wherein the reversing valve is used for assisting the reversing of the piston; in the prior art, reference can be made to Chinese patent publication No. CN219035193U, which provides a graded braking impact device and a rock drill, the graded braking impact device comprises a shell, a cylinder sleeve, a reversing valve and a piston, the piston and the reversing valve are coaxially arranged in the cylinder sleeve, the inner wall surface of the cylinder sleeve is provided with a plurality of pressure equalizing grooves, the cylinder sleeve is arranged in the shell, the shell is provided with an oil inlet main path and an oil return main path, the cylinder sleeve is provided with an oil inlet branch path communicated with the oil inlet main path and an oil return branch path communicated with the oil return main path, and oil passes through the shell, the cylinder sleeve, the piston and the reversing valve to be contacted. The side of the piston, which is close to the drill tool, is used as the front, and the corresponding side of the piston, which is far away from the drill tool, is used as the rear. The front end of the piston is connected with the drill tool, and the rear end of the piston is connected with the reversing valve in a contact manner.

Referring to fig. 14, which is a schematic structural diagram of the hierarchical braking impact device of the patent, as can be seen from fig. 14, the reversing valve 3 is disposed at the rear end of the piston 4, and the impact structure is provided, so that the length of the piston is increased, and the overall volume of the rock drill is larger and not compact enough; and the action area of the reversing valve and the piston is limited to the rear end of the piston, the action area of the reversing valve and the piston is smaller, and the reversing auxiliary effect of the reversing valve on the piston is relatively smaller, so that the reversing efficiency of the piston is lower, and the development of high-frequency movement of the rock drill is not facilitated.

Disclosure of utility model

In order to solve the technical problems, the application provides an impact structure, wherein an oil distributing valve is of a sleeve valve type structure, the acting area of the oil distributing valve on a piston is larger, the auxiliary effect on the reversing of the piston is better, the reversing of the piston can be facilitated, and the length of the piston is effectively shortened; on the other hand, the application also provides a rock drill, the length of the piston of the impact structure of the rock drill is relatively short, the structure is compact, the whole size of the rock drill can be reduced, and the high-frequency movement development of the rock drill is facilitated.

In one aspect, the application provides an impact structure comprising a piston, a cylinder sleeve assembly and an oil distribution valve, wherein the piston and the oil distribution valve are coaxially arranged in the cylinder sleeve assembly;

The impact structure further comprises a piston front cavity and a piston rear cavity, the cylinder sleeve assembly is provided with an oil path channel communicated with the piston front cavity and the piston rear cavity, and the piston front cavity always keeps oil inlet;

The oil distribution valve is arranged on the piston, and can do reciprocating motion along the axial direction of the piston so as to change the communication relation between the piston and the oil path channel, thereby assisting the reversing of the piston.

Compared with the prior art, the impact structure has the advantages that the oil distributing valve is a sleeve valve type, is sleeved on the piston, can effectively reduce an oil path, and can effectively shorten the length of the piston; the action surface of the oil distributing valve and the piston is larger, so that the reversing efficiency of the oil distributing valve is high, and the auxiliary reversing action of the piston is facilitated; the oil distribution valve sleeve is arranged on the piston, and the oil distribution valve moves in the axial direction, so that the communication relation between the piston and the oil way is changed, the hydraulic acting force applied to the piston is changed, and the piston is assisted to reciprocate in the cavity; the advantage of setting like this lies in that the area of action of distributing valve is great, and its switching-over efficiency is higher, can play beneficial effect to the switching-over of piston, and impact structure's work efficiency further improves.

In some alternative embodiments, the front end of the piston is provided with a front acting surface, and the rear end of the piston is provided with a rear acting surface;

The active area of the front active surface is smaller than the active area of the rear active surface.

In some alternative embodiments, the front and rear ends of the piston are respectively sleeved with a bushing, and the front and rear ends of the piston are provided with a lubrication oil path for preventing the piston from dry grinding with the bushing.

In some alternative embodiments, the piston front chamber is provided with a brake front chamber for braking the piston stroke;

The piston rear cavity is provided with a brake rear cavity for braking the return stroke of the piston.

In some alternative embodiments, the oil path of the front cavity of the piston comprises a front cavity oil inlet oil path and a front cavity oil return oil path, and the front cavity oil inlet oil path is always communicated;

the oil path channel of the rear cavity of the piston comprises a rear cavity oil inlet oil path and a rear cavity oil return oil path;

The front cavity oil inlet oil way, the front cavity oil return oil way, the rear cavity oil return oil way and the rear cavity oil inlet oil way are sequentially arranged along the axial direction of the piston.

In some optional embodiments, the cylinder sleeve component is further provided with a signal judging oil circuit, and the signal judging oil circuit is divided into a piston judging oil circuit and an oil distributing valve judging oil circuit;

The piston judging oil way is arranged between the front cavity oil inlet oil way and the front cavity oil return oil way;

The oil distribution valve judging oil way is arranged between the rear cavity oil return oil way and the rear cavity oil inlet oil way.

In some alternative embodiments, the impact structure further comprises an oil distribution valve cavity for mounting an oil distribution valve;

A valve braking cavity is arranged in the oil distributing valve cavity and is used for braking the oil distributing valve;

A valve oil return oil way is arranged in the oil distribution valve cavity and is communicated with the valve braking cavity;

The valve oil return oil way is arranged between the oil distribution valve judging oil way and the rear cavity oil inlet oil way.

In some alternative embodiments, the return motion of the piston comprises a return acceleration stage and a return braking stage, the return acceleration stage of the piston has a stroke of L1, and the return braking distance of X, wherein L1> X;

the set stroke of the piston before entering the braking rear cavity is L2, wherein L2 is more than L1;

The axial length of the braking rear cavity is L5, wherein X is more than L5.

In some alternative embodiments, the piston is preset with a first safety distance L3 during the stroke movement, the first safety distance being the distance before the piston hits into the pre-braking chamber, wherein L3 is larger than the normal drilling amount of the rock drill;

The piston is provided with a second safety distance L4 in advance in the stroke movement, wherein the second safety distance is the axial length of the front braking cavity, and L4 is more than L3.

The impact structure of the application has at least the following technical effects:

The sleeve valve type oil distributing valve effectively shortens the length of the piston, so that the oil way of the impact structure is relatively less, the acting area of the oil distributing valve is larger, and the reversing effect of the oil distributing valve on the piston is better;

by arranging the front braking cavity and the rear braking cavity, the safety braking effect can be achieved on the stroke and return stroke of the piston, the piston is prevented from impacting the cylinder body, and the piston is hydraulically protected;

The signal judgment oil way is arranged, so that position information can be provided for the oil distribution valve, and the auxiliary effect of the oil distribution valve on the reciprocating motion of the piston in the cavity is better;

Through rationally setting up the area ratio of piston front acting surface and rear acting surface, can make the impact structure have great impact energy to can also reduce the time of return braking, with the improvement impact frequency.

In a second aspect, the application also provides a rock drill comprising an impact structure as described in any one of the embodiments above. The piston of the impact structure of the rock drill is shorter, so that the rock drill has compact overall structure and smaller volume; and the impact efficiency is higher, so that the working efficiency of the rock drill is greatly enhanced.

Drawings

Fig. 1 is a schematic cross-sectional view of an anti-seize structure for a rock drill according to an embodiment of the application;

FIG. 2 is a schematic cross-sectional view of a first stage of motion of an impact structure according to an embodiment of the application;

FIG. 3 is a schematic cross-sectional view of a second stage of motion of an impact structure according to an embodiment of the application;

FIG. 4 is a schematic cross-sectional view of a third stage of motion of an impact structure according to an embodiment of the application;

FIG. 5 is a schematic cross-sectional view of a fourth stage of motion of an impact structure according to an embodiment of the application;

FIG. 6 is a schematic cross-sectional view of a fifth stage of motion of an impact structure according to an embodiment of the application;

FIG. 7 is an enlarged schematic view of portion A of FIG. 1;

FIG. 8 is an enlarged partial schematic view of FIG. 2;

FIG. 9 is an enlarged partial schematic view of FIG. 3;

FIG. 10 is an enlarged partial schematic view of FIG. 4;

FIG. 11 is an enlarged partial schematic view of FIG. 5;

FIG. 12 is an enlarged partial schematic view of FIG. 6;

FIG. 13 is an enlarged schematic view of portion B of FIG. 1;

Fig. 14 is a schematic structural view of a prior art stepped brake impact device.

Reference numerals:

1. an oil distribution valve; 2. a cylinder liner assembly; 3. a piston; 4. a bushing;

21. a piston front chamber; 22. a piston rear chamber; 23. a signal judging oil path; 24. an oil distribution valve cavity;

211. an oil inlet oil way of the front cavity; 212. A front cavity oil return oil way; 213. A brake front chamber;

221. an oil inlet circuit of the rear cavity; 222. A rear cavity oil return oil way; 223. A brake rear chamber;

231. Judging an oil way by a piston; 232. Judging an oil way by the oil distributing valve;

241. a valve braking chamber; 242. a valve oil return path; 243. a variable oil chamber;

31. a front active surface; 32. a rear acting surface; 33. a piston step;

41. And a lubrication oil path.

Detailed Description

In order to better understand the technical solutions of the present disclosure, the present disclosure will be described in detail, clearly and completely with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present disclosure.

In the description of the present application, the description of the first and second is only for the purpose of distinguishing technical features, and should not be construed as indicating or implying relative importance or implying the number of technical features indicated or the precedence of the technical features indicated.

It will be appreciated by those skilled in the art that in the present disclosure, the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc. refer to an orientation or positional relationship based on that shown in the drawings, which is merely for convenience of description and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore the above terms should not be construed as limiting the present application.

The application is described in further detail below with reference to the accompanying drawings, see for example figures 1 to 14.

In a first aspect, as shown in fig. 1 and 7, the present application provides an impact structure adapted to a hydraulic rock drill, which in operation causes a piston 3 to reciprocate at high frequency, constantly impacting a shank adapter, so that the shank adapter applies an impact force to rock, thereby shearing the rock; in this embodiment, the impact structure includes a piston 3, a cylinder sleeve assembly 2 and an oil distributing valve 1 (may also be referred to as a reversing valve), where the oil distributing valve 1 and the piston 3 are coaxially disposed in the cylinder sleeve assembly 2, and the oil distributing valve 1 and the piston 3 can both reciprocate along the same axis in the cavity;

The cylinder sleeve assembly 2 is provided with an oil path channel communicated with the front piston cavity 21 and the rear piston cavity 22, the external oil supply device feeds high-pressure oil or returns high-pressure oil to the rear piston cavity 22 or the front piston cavity 21 through the oil path channel, and the acting force is generated on the piston 3 through the action of hydraulic oil and the piston 3; in this embodiment, the front piston chamber 21 always keeps oil feeding, that is, the front end of the piston 3 always receives an acting force, the oil distributing valve 1 is sleeved on the piston 3, and the oil distributing valve 1 makes a reciprocating motion along the axial direction of the piston 3 so as to change the communication relationship between the rear piston chamber 22 and the oil path channel, thereby assisting the reversing of the piston 3.

Further, as shown in fig. 7, the oil distributing valve 1 is sleeved on the piston step 33, and the piston step 33 is located at the rear end portion of the piston 3, that is, the oil distributing valve 1 is directly sleeved on the piston step 33, so that the length of the piston 3 can be effectively shortened, and the impact structure is compact. The oil distributing valve 1 is positioned at the position of the rear cavity 22 of the piston, when the oil distributing valve 1 moves to enable an oil path channel of the rear cavity 22 of the piston to be communicated with oil inlet, the rear end of the piston 3 receives forward acting force which is larger than backward acting force received by the front end of the piston 3, and then the piston 3 moves forwards; when the oil distributing valve 1 moves to enable the oil path channel of the piston rear cavity 22 to be communicated with oil inlet, the rear end of the piston 3 receives forward acting force smaller than backward acting force received by the front end of the piston 3, and then the piston 3 moves backward;

Namely, the auxiliary piston 3 can be commutated by only changing the communication condition of the oil passage of the rear piston cavity 22 and the piston 3, so that the number of the oil passage of the piston 3 is relatively small and the structure is relatively simple for the integral impact structure; compared with the structure that the oil distribution valve 1 is arranged on the rear end face of the piston 3 in the prior art, the sleeve valve type structure of the embodiment enables the acting face of the oil distribution valve 1 and the acting face of the piston 3 to be large, so that the reversing efficiency of the oil distribution valve 1 is high, and the auxiliary reversing effect on the piston 3 is facilitated.

Further, as shown in fig. 1 and 7, the oil path of the front piston chamber 21 includes a front chamber oil inlet path 211 and a front chamber oil return path 212, and the front chamber oil inlet path 211 is always communicated, that is, no matter where the piston 3 moves in the chamber, the front chamber oil inlet path 211 always keeps oil inlet, that is, the front end of the piston 3 always receives the acting force of the hydraulic oil of the front chamber oil inlet path 211, so that the front piston chamber 21 is in a constant pressure state;

When the oil distribution valve 1 makes axial reciprocating motion, the oil channel is arranged on the cylinder body, and the oil distribution valve 1 is positioned between the cylinder body and the piston 3, so that the oil distribution valve 1 can block the oil channel to change the communication condition of the rear cavity oil inlet oil channel 221 or the rear cavity oil return oil channel 222 and the rear cavity 22, and when the rear cavity oil inlet oil channel 221 is communicated with the rear cavity 22 of the piston, hydraulic oil acts on the rear end of the piston 3, and the acting force born by the rear end of the piston 3 is increased; when the rear cavity oil return oil way 222 is communicated with the piston rear cavity 22, the acting force applied to the rear end of the piston 3 is reduced;

In the present embodiment, as shown in fig. 7, a front chamber oil intake passage 211, a front chamber oil return passage 212, a rear chamber oil return passage 222, and a rear chamber oil intake passage 221 are sequentially provided along the axial direction of the piston 3; the advantage of this arrangement is that the pressure action of the hydraulic oil on the piston 3 is concentrated on the front end and the rear end of the piston 3, so that the action effect on the forward and backward movement of the piston 3 can be effectively enhanced, and the efficiency of reciprocating movement of the piston 3 is improved.

In another alternative embodiment of the present application, as shown in fig. 7, a front acting surface 31 is provided at the front end of the piston 3, a rear acting surface 32 is provided at the rear end of the piston 3, the front acting surface 31 and the rear acting surface 32 are disposed opposite to each other, when the front acting surface 31 is subjected to hydraulic pressure, a rearward acting force is generated on the piston 3, and when the rear acting surface 32 is subjected to hydraulic pressure, a forward acting force is generated on the piston 3; the action area of the front action surface 31 is smaller than that of the rear action surface 32, so that the rock drill is guaranteed to have larger impact energy under a certain stroke, the time of return braking can be reduced, and the impact frequency of the rock drill is improved.

Further, the ratio of the active area of the front active surface 31 to the active area of the rear active surface 32 is substantially 1:3; at this ratio the impact energy of the impact structure is better, the return braking time is relatively smaller and the impact frequency of the rock drill is better.

Further, as shown in fig. 7, the rear acting surface 32 is substantially planar, and is disposed along the radial direction of the piston 3 and substantially parallel to the radial surface, so that the advantage of this arrangement is that when a hydraulic pressure acts on the rear acting surface 32, the thrust force generated on the piston 3 is substantially parallel to the axial direction of the piston 3, and the working efficiency of the hydraulic oil and the rear acting surface 32 is greatly improved, so that the forward impact force of the piston 3 is greater and the speed is faster.

In another alternative embodiment of the present application, as shown in fig. 1, the front and rear ends of the piston 3 are respectively sleeved with the bushing 4, the front and rear ends of the piston 3 are provided with the lubrication oil path 41, the lubrication oil path 41 is always connected with the return oil, and the lubrication oil path 41 is used for preventing the piston 3 from dry grinding with the bushing 4, thereby prolonging the service lives of the piston 3 and the bushing 4 and improving the sensitivity of the piston 3.

In an alternative embodiment of the present application, as shown in fig. 7, the piston front chamber 21 is provided with a brake front chamber 213 for braking the stroke of the piston 3, the brake front chamber 213 being located at a more front end portion of the piston 3; the piston rear chamber 22 is provided with a brake rear chamber 223 for braking the return stroke of the piston 3, and the brake rear chamber 223 is located at the rear end portion of the piston 3. In the present embodiment, the front braking chamber 213 and the rear braking chamber 223 are substantially dead braking chambers, which can perform a safe braking effect on the stroke and return process of the piston 3, prevent the piston 3 from striking the cylinder, and perform hydraulic protection on the piston 3. In the present embodiment, the brake front chamber 213 is located on the front side of the front chamber oil feed passage 211, and the brake rear chamber 223 is located on the rear side of the rear chamber oil feed passage 221.

In another alternative embodiment of the present application, as shown in fig. 7, a signal judging oil path 23 is further provided on the cylinder liner assembly 2, and the signal judging oil path 23 is divided into a piston judging oil path 231 and an oil distributing valve judging oil path 232; the piston judging oil path 231 is arranged between the front cavity oil inlet oil path 211 and the front cavity oil return oil path 212, and then the piston judging oil path 231 can be communicated with the front cavity oil return oil path 212 or the front cavity oil inlet oil path 211; the oil distribution valve judging oil passage 232 is provided between the rear chamber oil return oil passage 222 and the rear chamber oil intake oil passage 221. In this embodiment, the signal determination oil path 23 can provide position information for the oil distribution valve 1, when the piston 3 moves to a specified position, the communication relationship between the signal determination oil path 23 and the oil path of the piston 3 will change, the piston determination oil path 231 is communicated with the oil distribution valve determination oil path 232, and when the piston determination oil path 231 is communicated with the front cavity oil inlet oil path 211 or the front cavity oil return oil path 212, both the signal determination oil path 23 can act on the oil distribution valve 1, so that the oil distribution valve 1 can acquire the position of the piston 3 through the signal determination oil path 23, so that the oil distribution valve 1 can be commutated in time to assist the commutation of the piston 3.

Further, as shown in fig. 7, the cylinder sleeve assembly 2 is provided with an oil distributing valve cavity 24 for installing the oil distributing valve 1, the oil distributing valve cavity 24 is communicated with the rear cavity 22, the rear cavity oil inlet oil way 221 and the rear cavity oil return oil way 222 of the piston, and by arranging the oil distributing valve cavity 24, the auxiliary reversing function of the oil distributing valve 1 on the piston 3 can be ensured, and the oil distributing valve 1 can axially and radially limit the reciprocating motion of the oil distributing valve 1 relative to the piston 3;

As shown in fig. 7, a valve braking cavity 241 is arranged in the oil distributing valve cavity 24, and the valve braking cavity 241 is used for braking the oil distributing valve 1, so that the oil distributing valve 1 can be stably decelerated to reach a limit position, and damage caused by impact of the oil distributing valve 1 is reduced; a valve oil return path 242 is arranged in the oil distribution valve cavity 24, and the valve oil return path 242 is communicated with the valve braking cavity 241; the valve oil return oil path 242 is arranged between the oil distribution valve judging oil path 232 and the rear cavity oil inlet oil path 221, so that a gear separation function is achieved between the oil distribution valve judging oil path 232 and the rear cavity oil inlet path, acting force applied to the oil distribution valve 1 is concentrated at the front end and the rear end, and reversing sensitivity of the oil distribution valve 1 can be effectively improved.

Further, as shown in fig. 13, a variable oil cavity 243 is further provided in the oil distributing valve cavity 24, the variable oil cavity 243 is located at the front end of the oil distributing valve 1, the variable oil cavity 243 is communicated with the oil distributing valve judging oil path 232, the variable oil cavity 243 is located between the valve braking cavity 241 and the rear cavity oil return oil path 222, after the variable oil cavity 243 is communicated with the oil distributing valve judging oil path 232, the communicating relationship between the oil path passages of the rear piston cavity 22 and the front piston cavity 21 generated by the change of the movement position of the piston 3 acts on the front end of the oil distributing valve 1, so that the stress of the front end of the oil distributing valve 1 is changed, and the reversing of the oil distributing valve 1 can be assisted.

Further, as shown in fig. 13, the variable oil chamber 243 of the oil distribution valve 1 has an action portion, and the action area of the action portion is larger than the action area of the rear end of the oil distribution valve 1.

In another alternative embodiment of the impact structure of the present application, the piston 3 movement process includes a return movement to create a reciprocating movement of the piston 3 within the cavity; the return motion of the piston 3 comprises a return acceleration stage and a return braking stage, wherein the return acceleration stage of the piston 3 has a stroke of L1 and the return braking distance of X, wherein L1 is more than or equal to 2X, and the arrangement has the advantages that the return speed of the piston 3 can be accelerated, the return time of the piston 3 is reduced, and then the impact rate of an impact structure is improved;

Further, the set stroke of the piston 3 before entering the brake rear cavity 223 is L2, wherein L2 is more than or equal to 2L1; the advantage of this arrangement is that even though the pressure applied to the piston 3 may be in an unstable state, by setting the setting before the piston 3 enters the brake rear chamber 223 to be greater than the stroke of the return acceleration stage, the piston 3 can enter the return brake stage more smoothly, and then the piston 3 cannot be difficult to decelerate to impact the cylinder body due to the excessive speed of the return acceleration stage, so that the return stroke of the piston 3 can be effectively protected;

Further, the axial length of the brake rear chamber 223 is L5, wherein X > L5; the advantage of this arrangement is that it is possible to ensure that when the shank of the rock drill is in an off-side condition, the piston 3 is able to further rely on the dead space to brake the return stroke of the piston 3 in a decelerating manner, reducing the damage caused by the piston 3 striking the cylinder.

Further, the movement process of the piston 3 comprises stroke movement, namely, the piston 3 impacts the drill shank when the piston 3 makes stroke movement; the piston 3 is preset with a first safety distance L3 during the stroke movement, the first safety distance being the distance before the piston 3 hits into the braking front chamber 213, wherein L3 is larger than the normal drilling amount of the rock drill; the advantage of this arrangement is that it is possible to ensure that the piston 3 does not enter the pre-brake chamber 213 during normal rock drilling conditions, resulting in a loss of impact energy and a reduction of impact frequency, and to improve the rock drilling efficiency of the rock drill.

Further, the piston 3 is preset with a second safety distance L4 during the stroke movement, the second safety distance being the axial length of the brake front cavity 213, wherein L4 > L3; the advantage of this is that it is ensured that when the shank of the rock drill is in an off-side condition, the piston 3 is braked further by means of the brake front chamber 213 to decelerate the piston 3 after impact, reducing damage to the piston 3 caused by impact to the cylinder.

The working process of the impact structure comprises five stages, wherein the movement of the piston 3 of the impact structure comprises a return stroke process and a stroke process, the piston 3 comprises a return stroke acceleration initial stage, a return stroke acceleration middle stage and a return stroke braking stage in the return stroke process, and the piston 3 comprises a stroke stage and an impact stage in the stroke process;

Specifically, in connection with fig. 2 to 12, it is shown that:

Step one, accelerating the motion process of the piston 3 from the initial state to the return stroke in the initial stage; as shown in fig. 2 and 8, the piston 3 is located at the impact point position, which is the initial position of the piston 3; in this stage, the front chamber is always in oil feed state, the piston front chamber 21 is in oil feed state, the piston judging oil path 231 is communicated with the front chamber is always in oil feed state, namely the oil distributing valve judging oil path 232 is communicated with the oil distributing valve 1, the variable oil cavity 243 of the oil distributing valve 1 is in oil feed state, the front end of the oil distributing valve 1 receives high pressure oil acting force, and the acting area of the force receiving part at the front end of the oil distributing valve 1 is larger than that at the rear end, so that the oil distributing valve 1 moves to the rear end; the oil distributing valve 1 moves backwards until the oil inlet oil way of the rear cavity 22 of the piston is blocked, and the oil return oil way 222 of the rear cavity of the piston 3 is communicated with the rear cavity 22 of the piston, the acting force of the front end of the piston 3 is larger than that of the rear end, so that the piston 3 moves backwards in an accelerating way;

step two, a movement process of the piston 3 from the initial stage of return stroke acceleration to the middle stage of return stroke acceleration; as shown in fig. 3 and 9, in the return intermediate acceleration stage, the piston determination oil passage 231 is disconnected from the front chamber oil intake oil passage 211, the oil distribution valve determination oil passage 232 is also disconnected from the front chamber oil intake oil passage 211, and in this stage, the piston determination oil passage 231 is not communicated with the front chamber oil return oil passage 212, and then the variable oil chamber 243 of the oil distribution valve 1 becomes a dead chamber, the pressure in the dead chamber is unchanged, and the pressure at the front end of the oil distribution valve 1 is greater than the rear end, and thus remains motionless; the rear cavity oil return oil path 222 is communicated with the rear cavity 22 of the piston, so that the acting force applied to the front end of the piston 3 is larger than that applied to the rear end, and the piston 3 continues to accelerate to move backwards;

Step three, a movement process of the piston 3 from a return acceleration stage to a return braking stage; as shown in fig. 4 and 10, the piston judging oil path 231 is communicated with the front cavity oil return oil path 212, the variable oil cavity 243 of the oil distributing valve 1 returns oil, the oil pressure at the front end of the oil distributing valve 1 is reduced, the oil distributing valve 1 moves forwards to reach the forefront position, the rear cavity oil inlet oil path 221 is communicated with the rear piston cavity 22, the action area of the rear piston cavity 22 is larger than that of the front cavity, and the piston 3 carries out return braking movement;

Stage four, which is the movement process of the piston 3 from the return braking stage to the stroke stage; as shown in fig. 5 and 11, the oil distributing valve 1 is located at the front end, the rear cavity 22 of the piston is communicated with the oil inlet channel 221 of the rear cavity, the acting area of the rear cavity 22 of the piston is larger than that of the front cavity, and the piston 3 moves forwards, which is the stroke movement of the piston 3;

Stage five, which is the motion process from the stage of the piston 3 stroke to the striking; as shown in fig. 6 and 12, the piston judging oil path 231 is communicated with the front cavity oil inlet oil path 211, namely, the variable oil cavity 243 of the oil distributing valve 1 is filled with oil, the rear end of the oil distributing valve 1 is acted by the rear cavity oil inlet oil path 221, the acting forces on the two ends of the oil distributing valve 1 are opposite, but the acting area of the variable oil cavity 243 is larger, so that the front end of the oil distributing valve 1 is stressed more than the rear end, and the oil distributing valve 1 moves backwards;

After the oil distributing valve 1 finishes the direction change, the piston 3 reaches the rearmost side, the front cavity oil inlet oil way 211 of the piston front cavity 21 always feeds oil, the piston rear cavity 22 is about to be communicated with the rear cavity oil return oil way 222, and the piston 3 is impacted;

The oil distributing valve 1 moves backwards to block the rear cavity oil inlet oil way 221, the rear cavity oil return oil way 222 is communicated with the piston 3, and the piston 3 enters a return stroke stage.

In a second aspect, the application also provides a rock drill comprising an impact structure according to any one of the embodiments described above. The piston 3 of the impact structure of the rock drill is shorter, so that the rock drill has compact overall structure and smaller volume; and the impact efficiency of the rock drill is higher, so that the working efficiency of the rock drill is greatly enhanced.

It should be noted that, in the case that the embodiments of the present application do not conflict with the solutions and the technical solutions can coexist, new embodiments may be arbitrarily combined.

The foregoing has outlined rather broadly the more detailed description of the application in order that the detailed description of the application that follows may be better understood, and in order that the present application may be better understood. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the application can be made without departing from the principles of the application and these modifications and adaptations are intended to be within the scope of the application as defined in the following claims.

Claims (9)

1. The impact structure is characterized by comprising a piston (3), a cylinder sleeve assembly (2) and an oil distribution valve (1), wherein the piston (3) and the oil distribution valve (1) are coaxially arranged in the cylinder sleeve assembly (2);

The impact structure further comprises a piston front cavity (21) and a piston rear cavity (22), wherein an oil path channel communicated with the piston front cavity (21) and the piston rear cavity (22) is arranged on the cylinder sleeve assembly (2), and the piston front cavity (21) always keeps oil inlet;

The oil distributing valve (1) is sleeved on the piston (3), and the oil distributing valve (1) can reciprocate along the axial direction of the piston (3) so as to change the communication relation between the piston (3) and the oil path channel, thereby assisting the reversing of the piston (3);

The front end of the piston (3) is provided with a front acting surface (31), and the rear end of the piston (3) is provided with a rear acting surface (32);

The active area of the front active surface (31) is smaller than the active area of the rear active surface (32).

2. The impact structure of claim 1, wherein the impact structure comprises,

The front end and the rear end of the piston (3) are respectively sleeved with a bushing (4), the front end and the rear end of the piston (3) are provided with a lubricating oil circuit (41), and the lubricating oil circuit (41) is used for preventing the piston (3) from being dry-ground with the bushings (4).

3. The impact structure of claim 1, wherein the impact structure comprises,

The piston front cavity (21) is provided with a braking front cavity (213) for braking the stroke of the piston (3);

The piston rear chamber (22) is provided with a brake rear chamber (223) for braking the return stroke of the piston (3).

4. An impact structure as claimed in any one of claims 1 to 3, wherein,

The oil path channel of the front piston cavity (21) comprises a front cavity oil inlet oil path (211) and a front cavity oil return oil path (212), and the front cavity oil inlet oil path (211) is always communicated;

The oil path channel of the rear cavity (22) of the piston comprises a rear cavity oil inlet oil path (221) and a rear cavity oil return oil path (222);

The front cavity oil inlet oil way (211), the front cavity oil return oil way (212), the rear cavity oil return oil way (222) and the rear cavity oil inlet oil way (221) are sequentially arranged along the axial direction of the piston (3).

5. The impact structure of claim 4, wherein the impact structure comprises,

The cylinder sleeve assembly (2) is also provided with a signal judging oil circuit (23), and the signal judging oil circuit (23) is divided into a piston judging oil circuit (231) and an oil distributing valve judging oil circuit (232);

The piston judging oil way (231) is arranged between the front cavity oil inlet oil way (211) and the front cavity oil return oil way (212);

The oil distribution valve judging oil way (232) is arranged between the rear cavity oil return oil way (222) and the rear cavity oil inlet oil way (221).

6. The impact structure of claim 5, wherein the impact structure comprises,

The impact structure also comprises an oil distributing valve cavity (24) for installing the oil distributing valve (1);

A valve braking cavity (241) is arranged in the oil distributing valve cavity (24), and the valve braking cavity (241) is used for braking the oil distributing valve (1);

A valve oil return oil way (242) is arranged in the oil distribution valve cavity (24), and the valve oil return oil way (242) is communicated with the valve braking cavity (241);

The valve oil return oil path (242) is arranged between the oil distribution valve judging oil path (232) and the rear cavity oil inlet oil path (221).

7. The impact structure of claim 6, wherein the impact structure comprises,

The return motion of the piston (3) comprises a return acceleration stage and a return braking stage, wherein the return acceleration stage of the piston (3) has a stroke of L1, and the return braking distance is X, wherein L1> X;

The set stroke of the piston (3) before entering the brake rear cavity (223) is L2, wherein L2 is more than L1;

The axial length of the brake rear cavity (223) is L5, wherein X > L5.

8. The impact structure of claim 7, wherein the impact structure comprises,

The piston (3) is preset with a first safety distance L3 in the stroke movement, wherein the first safety distance is the distance before the piston (3) impacts into the front braking cavity (213), and L3 is larger than the normal drilling amount of the rock drill;

The piston (3) is pre-set with a second safety distance L4 during the stroke movement, which is the axial length of the brake front chamber (213), wherein L4 > L3.

9. A rock drill, characterized in that the rock drill comprises an impact structure as claimed in any one of the preceding claims 1-8.