Anti-jamming structure and hydraulic rock drill

Abstract

The application provides a kind of anti-stuck structure, applied to hydraulic rock drill, including piston, cylinder and reversing valve, piston and reversing valve coaxial setting in cylinder, reversing valve is located between piston and cylinder, reversing valve is used to assist piston to change direction;Cylinder and piston are equipped with brake dead space, piston rear cavity for oil inlet and piston front cavity;Wherein, reversing valve is equipped with the anti-stuck part that protrudes towards piston direction, piston is equipped with the recessed slot that recesses towards piston center, anti-stuck part and recessed slot cooperate to prevent piston from being stuck in brake dead space.By the effect of anti-stuck part and recessed slot, piston can quickly exit after entering brake dead space, thereby preventing the situation that piston is stuck in brake dead space occurs.Another aspect provides a kind of hydraulic rock drill, including the anti-stuck structure described above, piston is not easy to be stuck in brake dead space, reduces the time, manpower consumed due to piston stuck, so that the working efficiency of rock drill is improved.

Description

Technical Field

[0001] This application relates to the field of rock drill technology, specifically to an anti-jamming structure and a hydraulic rock drill. Background Technology

[0002] A rock drill is a tool used for quarrying stone, mainly consisting of an impact mechanism and a rotary mechanism. The impact mechanism includes a cylinder and an impact piston that slides back and forth within the cylinder. The rotary mechanism includes a chisel. When the impact piston extends out of the cylinder to its limit position, it strikes the chisel, which transmits the impact force to the rock to create a hole.

[0003] In existing technology, to prevent the piston from overshooting the rear end and impacting the cylinder, and considering minimizing the increase in the overall length of the equipment, rock drills generally require brake dead chambers at both ends of the piston. The front end typically relies on mechanical restraint with the piston impactor to reduce dry-firing, while the rear end relies solely on the brake dead chamber for hydraulic protection.

[0004] In actual use, due to pressure exceeding the rated pressure, the piston stroke increases, causing the piston to enter the rear brake dead chamber. Alternatively, after disassembly and maintenance, the piston may be reassembled to the rear side, causing it to enter the rear brake dead chamber. Or, during startup, there may be no oil in the rock drill chamber, causing the rock drill to tilt upwards and the piston's own weight to affect the rear brake dead chamber, resulting in no hydraulic resistance and the piston sliding into the rear brake dead chamber. Although the existence of the rear brake dead chamber effectively protects the piston to some extent, it also brings the problem of the piston getting stuck in the dead chamber after entering it. This requires the use of a vibrating rock drill to remove the piston from the rear brake dead chamber, or even to stop the machine.

[0005] In summary, there is room for further improvement in existing hydraulic rock drill technologies. Summary of the Invention

[0006] To address the aforementioned technical problems, this application provides, on the one hand, an anti-jamming structure that effectively facilitates the piston's rapid withdrawal after entering the braking dead chamber, thereby preventing piston jamming; on the other hand, this application also provides a hydraulic rock drill with an anti-jamming structure, which reduces the probability of jamming in the hydraulic rock drill and greatly improves the working efficiency of the rock drill.

[0007] In a first aspect, this application provides an anti-jamming structure for use in a hydraulic rock drill. The anti-jamming structure includes a piston, a cylinder, and a reversing valve. The piston and the reversing valve are coaxially disposed in the cylinder. The reversing valve is located between the piston and the cylinder and is used to assist the piston in reversing.

[0008] The cylinder body and the piston are provided with a braking dead chamber, a piston rear chamber for oil inlet and a piston front chamber;

[0009] The reversing valve is provided with an anti-jamming part protruding towards the piston, and the piston is provided with a relief groove recessed towards the center of the piston. The anti-jamming part cooperates with the relief groove to prevent the piston from getting stuck in the brake dead chamber.

[0010] Compared with the prior art, the anti-jamming structure applied to a hydraulic rock drill in this application has an anti-jamming part on the reversing valve used to assist the piston in reversing, and a relief groove recessed towards the center of the piston on the piston. When the reversing valve moves axially relative to the piston, the anti-jamming part can act with the steps at both ends of the relief groove, thereby generating a thrust on the piston. When the piston enters the brake dead chamber, oil is introduced into the front chamber or rear chamber of the piston. The hydraulic oil can generate a thrust on the reversing valve, thereby pushing the piston out of the brake dead chamber. This allows the piston to exit quickly after entering the brake dead chamber, thus preventing the piston from getting stuck in the brake dead chamber.

[0011] In addition, the clearance groove shortens the action path of the anti-jamming part on the piston, reduces the friction and contact area between the directional valve and the piston when the valve moves, and thus reduces the probability of the piston being damaged by the directional valve.

[0012] In some optional embodiments, a braking part is provided on the outer peripheral wall of the reversing valve, and a valve braking chamber that cooperates with the braking part is provided between the cylinder and the reversing valve.

[0013] In some alternative embodiments, the braking part is a protrusion that protrudes toward the cylinder body;

[0014] There is an oil outlet gap between the top of the brake unit and the cylinder.

[0015] In some optional embodiments, the directional valve has at least one buoyancy groove on its outer peripheral wall;

[0016] The buoyancy groove is recessed towards the center of the piston.

[0017] In some alternative embodiments, the radial depth of the buoyancy groove is 1 to 4 mm.

[0018] In some alternative embodiments, the radial depth of the relief groove is 1 to 2 mm.

[0019] In some optional embodiments, the steps at both ends of the relief groove are provided with buffer portions, and the surface of the buffer portions is an inclined surface.

[0020] In some alternative embodiments, there is a gap between the lower end of the anti-jamming part and the relief groove.

[0021] In some alternative embodiments, the bottom of the anti-jamming part is flat.

[0022] The anti-jamming structure of this application has at least the following technical effects:

[0023] By setting an anti-jamming part on the reversing valve that cooperates with the piston's clearance groove, the piston can be quickly withdrawn after entering the brake dead chamber, preventing the piston from getting stuck in the brake dead chamber.

[0024] By setting buffer parts on the steps at both ends of the relief groove and setting the surface of the buffer parts as inclined surfaces, when the inclined surface of the buffer parts interacts with the anti-jamming parts, the axial force exerted by the anti-jamming parts on the piston is decomposed, thereby reducing the stress concentration between the anti-jamming parts and the piston, reducing the wear force of the reversing valve on the piston, thereby further reducing the probability of the piston being damaged and further ensuring the service life of the piston.

[0025] By setting a buoyancy groove on the directional valve, a supporting force can be provided to the directional valve, thereby effectively reducing the hydraulic clamping force caused by the eccentricity of the directional valve.

[0026] Secondly, this application also provides a hydraulic rock drill, which includes an anti-jamming structure as described in any of the above embodiments. The hydraulic rock drill of this application has an anti-jamming structure, making it less prone to jamming in the braking dead chamber, thereby resulting in higher working efficiency. Attached Figure Description

[0027] Figure 1 This is a cross-sectional schematic diagram of an anti-jamming structure for a rock drill according to an embodiment of this application;

[0028] Figure 2 This is a cross-sectional schematic diagram of a piston according to an embodiment of this application;

[0029] Figure 3 This is a cross-sectional schematic diagram of a reversing valve according to an embodiment of this application;

[0030] Figure 4 yes Figure 1 A magnified view of a portion of the image;

[0031] Figure 5 yes Figure 2 A magnified view of a portion of the image;

[0032] Figure 6 yes Figure 3 A magnified view of a portion of the image;

[0033] Figure 7 This is a cross-sectional schematic diagram showing the connection between the reversing valve braking part and the valve braking chamber according to an embodiment of this application.

[0034] Figure label:

[0035] 1. Reversing valve; 2. Cylinder block; 3. Piston; 4. Brake dead chamber; 5. Valve brake chamber; 6. Piston front chamber; 7. Piston rear chamber;

[0036] 11. Anti-jamming section; 12. Braking section; 13. Buoyancy groove; 14. Oil outlet gap;

[0037] 31. Leaving groove; 32. Buffer section;

[0038] 41. Front brake dead chamber; 42. Rear brake dead chamber. Detailed Implementation

[0039] To enable those skilled in the art to better understand the technical solutions of this disclosure, the following detailed, clear, and complete description of this disclosure is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this disclosure and are not intended to limit it.

[0040] In the description of this application, the use of "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0041] Those skilled in the art should understand that in the disclosure of this application, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on this application.

[0042] The present application will now be described in further detail with reference to the accompanying drawings, see below. Figures 1 to 7 illustrate.

[0043] Firstly, this application provides an anti-jamming structure for use in a hydraulic rock drill. Located within the impact structure of the hydraulic rock drill, this structure provides an anti-jamming effect for the piston 3. (Reference) Figure 1As shown, the anti-jamming structure includes a piston 3, a cylinder 2, and a reversing valve 1. The piston 3 and the reversing valve 1 are coaxially arranged inside the cylinder 2. The reversing valve 1 is located between the cylinder 2 and the piston 3. Both the reversing valve 1 and the piston 3 can move axially within the cylinder liner. The reversing valve 1 moves within the cylinder 2 to change the oil flow status of the piston's rear chamber 7, thereby switching the magnitude of the thrust at the rear end face of the piston 3 and assisting the movement of the piston 3. A braking dead chamber 4 is provided between the cylinder 2 and the piston 3. There are two braking dead chambers 4, namely a rear front braking dead chamber 41 and a rear... The piston has a brake dead chamber 42, and a piston rear chamber 7 and a piston front chamber 6 for oil inlet are provided between the cylinder body 2 and the piston 3. By introducing hydraulic oil into the piston rear chamber 7 and the piston front chamber 6, pressure can be applied to the piston 3 and the reversing valve 1 to push the piston 3 to move. The front brake dead chamber 41 is located near the piston front chamber 6, and the rear brake dead chamber 42 is located near the piston rear chamber 7. Both are arranged along the axial direction of the piston 3. The brake dead chamber 4 can prevent the piston 3 from overstepping to the rearmost or foremost side, causing the piston 3 to hit the cylinder body 2.

[0044] like Figure 4 As shown, the reversing valve 1 is provided with an anti-jamming part 11 protruding towards the piston 3, and the piston 3 is provided with a relief groove 31 recessed towards the center of the piston 3. The anti-jamming part 11 and the relief groove 31 cooperate to prevent the piston 3 from getting stuck in the brake dead chamber 4. When the piston 3 finishes its impact or return motion and needs to switch to the next motion, oil is introduced into the piston front chamber 6 or piston rear chamber 7. The high-pressure oil acts on the reversing valve 1, generating a preliminary force for the reversing valve 1 to move. Then, through the action of the anti-jamming part 11 and the steps at both ends of the relief groove 31, a pushing force is generated on the piston 3, thereby pushing the piston 3 out of the brake dead chamber 4. This allows the piston 3 to quickly exit after entering the brake dead chamber 4, thus preventing the piston 3 from getting stuck in the brake dead chamber 4.

[0045] In this embodiment, as Figure 2 , Figure 5 As shown, the anti-jamming part 11 is provided on the inner peripheral wall of the reversing valve 1. By setting the anti-jamming part 11 to protrude towards the piston 3, when the reversing valve 1 moves relative to the piston 3, the anti-jamming part 11 protrudes and interacts with the relief groove 31, thereby enabling the reversing valve 1 to easily push the piston 3 out of the brake dead chamber 4. While ensuring the pushing force of the anti-jamming part 11 on the piston 3, the volume of the anti-jamming part 11 is relatively small, saving the manufacturing materials and manufacturing cost of the reversing valve 1.

[0046] In this embodiment, as Figure 3 , Figure 6As shown, the two ends of the relief groove 31 form steps with the outer peripheral wall of the piston 3. By setting the relief groove 31, when the anti-jamming part 11 needs to act on the piston 3 to push the piston 3 out of the brake dead chamber 4, the anti-jamming part 11 can enter the directional groove and move along the axial direction of the piston 3. The anti-jamming part 11 can act on the steps at both ends of the relief groove 31. The anti-jamming part 11 applies a force to the steps at both ends of the relief groove 31, thereby applying a pushing force to the piston 3 and pushing the piston 3 out of the brake dead chamber 4. The setting of the relief groove 31 shortens the action path length of the anti-jamming part 11 on the piston 3, reduces the friction and contact area of ​​the reversing valve 1 on the piston 3, thereby reducing the probability of the piston 3 being damaged by the reversing valve 1.

[0047] Furthermore, the radial depth of the relief groove 31 is 1 to 2 mm. By reasonably setting the depth of the relief groove 31, on the one hand, the processing difficulty can be reduced, and on the other hand, the piston 3 protrusion in the relief groove 31 can be prevented from hitting the anti-jamming part 11 and damaging the piston 3 when the piston 3 expands due to heat.

[0048] Furthermore, such as Figure 4 As shown, there is a gap between the lower end of the anti-jamming part 11 and the relief groove 31. In this embodiment, the gap between the bottom of the relief groove 31 and the lower end of the anti-jamming part 11 serves two purposes. First, it prevents the anti-jamming part 11 from acting on the bottom of the relief groove 31 when the directional valve 1 moves axially relative to the piston 3, thus preventing friction between the anti-jamming part 11 and the relief groove 31 and damage to the piston 3. Second, it allows oil to enter between the piston 3 and the directional valve 1, and the oil can smoothly act on the steps of the anti-jamming part 11 and the relief groove 31 to generate force, thereby enabling the directional valve 1 to exert a better pushing force on the piston 3, resulting in a faster exit speed and more sensitive response from the piston 3 from the brake dead chamber 4. In addition, this gap allows oil to flow between the directional valve 1 and the cylinder 2, preventing oil from being blocked in the piston rear chamber 7.

[0049] In another optional embodiment of this application, the anti-jamming part 11 is further improved; such as... Figure 4 , Figure 6 As shown, in the cross section along the axial direction of the piston 3, the anti-jamming part 11 is a basic inverted triangle. The end of the anti-jamming part 11 closer to the piston 3 is smaller, and the end of the anti-jamming part 11 connected to the reversing valve 1 is larger. This allows the reaction force of the piston 3 on the anti-jamming part 11 to act on the inclined surface of the anti-jamming part 11 when the anti-jamming part 11 interacts with the piston 3, thereby decomposing the force, reducing stress concentration, and reducing the probability of the anti-jamming part 11 breaking.

[0050] In another optional embodiment of this application, the anti-jamming part 11 is further improved, such as... Figure 4 , Figure 6As shown, the bottom of the anti-jamming part 11 is flat, which allows the force to be distributed more widely when the reversing valve 1 and the piston 3 interact. The end of the anti-jamming part 11 will not be subjected to excessive force concentration at one point, and the probability of the end of the anti-jamming part 11 breaking can also be reduced. Furthermore, when the anti-jamming part 11 accidentally comes into contact with the outer peripheral wall of the piston 3, the contact area between the anti-jamming part 11 and the piston 3 is relatively large, so the force applied to the piston 3 will not be excessively concentrated at one point, reducing the impact damage to the contact part of the piston 3.

[0051] Furthermore, such as Figure 6 As shown, the anti-jamming part 11 is connected to the reversing valves 1 on the front and rear sides at different heights. The height at which the anti-jamming part 11 is connected to the front end of the reversing valve 1 is greater than the height at which it is connected to the rear end. The advantage of this design is that it makes it easier to process the anti-jamming part 11.

[0052] In another optional embodiment of this application, such as Figure 4 , Figure 5 As shown, buffer portions 32 are provided at both ends of the relief groove 31, and the surface of the buffer portion 32 is an inclined surface. When the anti-jamming portion 11 interacts with the piston 3, the inclined surface of the anti-jamming portion 11 and the buffer portion 32 interact, and the axial force exerted by the anti-jamming portion 11 on the piston 3 is decomposed, thereby reducing the stress concentration between the anti-jamming portion 11 and the piston 3, which can reduce the wear force of the reversing valve 1 on the piston 3, thereby further reducing the probability of the piston 3 being damaged and further ensuring the service life of the piston 3.

[0053] In another optional embodiment of this application, such as Figure 4 , Figure 6 , Figure 7 As shown, a braking part 12 is provided on the outer peripheral wall of the reversing valve 1, and a valve braking chamber 5 that cooperates with the braking part 12 is provided between the cylinder body 2 and the reversing valve 1. By extracting oil from the valve braking chamber 5, the hydraulic oil in the valve braking chamber 5 can be squeezed out through the clearance cooperation between the braking part 12 of the reversing valve 1 and the valve braking chamber 5 after the reversing valve 1 has completed the reversing, thereby realizing the smooth deceleration of the reversing valve 1 to the limit position and reducing the damage caused by the impact of the reversing valve 1.

[0054] Furthermore, such as Figure 4 , Figure 6 , Figure 7 As shown, the braking part 12 is a protrusion protruding towards the cylinder body 2; by setting the braking part 12 to protrude towards the cylinder body 2, when the reversing valve 1 moves, the braking part 12 can directly act on the side wall of the valve braking chamber 5, so that the volume of the braking part 12 is relatively small, saving the manufacturing materials and manufacturing cost of the reversing valve 1.

[0055] like Figure 7As shown, there is an oil outlet gap 14 between the top of the brake part 12 and the cylinder body 2, and the top of the brake part 12 has notches at both ends along the axial direction, such as... Figure 7 As shown, when the side wall of the brake part 12 is in contact with the inner wall of the valve brake chamber 5, the notch connects with the oil outlet gap 14 to form an oil outlet channel, so that when the brake part 12 interacts with the valve brake chamber 5 to squeeze out hydraulic oil, the hydraulic oil can flow out from the oil outlet channel; and the contact surface between the brake part 12 and the valve brake chamber 5 is a plane, which can increase the contact area between the brake part 12 and the valve brake chamber 5, and squeeze out the hydraulic oil in the valve brake chamber 5 as much as possible.

[0056] In another optional embodiment of this application, such as Figure 3 , Figure 6 As shown, the outer peripheral wall of the directional valve 1 is provided with at least one buoyancy groove 13. The buoyancy groove 13 is recessed towards the central axis of the piston 3 and is arranged along the outer peripheral wall of the piston 3. The buoyancy groove 13 is annular. By providing the buoyancy groove 13 on the directional valve 1, the hydraulic oil can flow into the buoyancy groove 13, thereby providing a supporting force to the directional valve 1. This effectively reduces the eccentricity of the directional valve 1 due to lateral force, and the resulting hydraulic clamping force, thereby preventing the directional valve 1 from clamping.

[0057] Furthermore, the radial depth of the buoyancy groove 13 is 1 to 4 mm. By reasonably setting the depth of the buoyancy groove 13, the supporting force on the piston 3 can be adjusted. Setting the depth of the buoyancy groove 13 within this range will ensure that the supporting effect on the piston 3 is optimal when the buoyancy groove 13 is filled with hydraulic oil.

[0058] Furthermore, such as Figure 6 As shown, the surface of the buoyancy groove 13 is arc-shaped, which can increase the contact area between the hydraulic oil and the buoyancy groove 13, thereby further increasing the supporting force on the reversing valve 1.

[0059] Furthermore, such as Figure 3 , Figure 6 As shown, the buoyancy grooves 13 are arranged on both sides of the braking part 12, which can effectively ensure that the overall supporting force of the reversing valve 1 is relatively even, so that the reversing valve 1 is under force balance. In actual use, the number and position of the buoyancy grooves 13 on both sides of the braking part 12 are reasonably arranged according to the setting position of the braking part 12, so that the reversing valve 1 can be under force balance as a whole. In this application, since the braking part 12 is set relatively far back, two buoyancy grooves 13 are set on the front side of the braking part 12 and one buoyancy groove 13 is set on the rear side of the braking part 12, so that the reversing valve 1 can be under force balance as much as possible.

[0060] The anti-jamming structure of this application, during use, combines with... Figure 4 As shown:

[0061] When piston 3 moves backward into the rear brake dead chamber 42, the hydraulic oil in the front valve brake chamber 5 decreases by returning oil from the valve brake chamber 5, and oil enters the rear chamber 7 of the piston. The hydraulic oil enters the valve brake chamber 5 at the rear end of the reversing valve 1, and also flows to the anti-jamming part 11 of the reversing valve 1, generating pressure on the reversing valve 1. Under the high pressure of the hydraulic oil, the reversing valve 1 moves forward.

[0062] When the reversing valve 1 moves to contact the buffer part 32 at the front end of the relief groove 31, the anti-jamming part 11 interacts with the buffer part 32 of the relief groove 31 to generate a forward force to push the piston 3 forward, so that the piston 3 can smoothly and quickly disengage from the rear brake dead chamber 42. The hydraulic oil enters the rear brake dead chamber 42 and exerts pressure on the piston 3 step that interacts with the rear brake dead chamber 4, causing the piston 3 to accelerate forward.

[0063] Secondly, this application provides a hydraulic rock drill, which includes an anti-jamming structure as described in any of the above embodiments. The rock drill of this application has an anti-jamming structure, making it less likely for its piston 3 to jam in the braking dead chamber 4, reducing the time and manpower wasted due to piston 3 jamming, thereby significantly improving the working efficiency of the rock drill.

[0064] It should be noted that the various embodiments of this application can be arbitrarily combined into new embodiments, provided that the solutions do not conflict and the technical solutions can coexist.

[0065] The present application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present application. The descriptions of the embodiments above are only for the purpose of helping to understand the present application and its core ideas. It should be noted that those skilled in the art can make several improvements and modifications to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. An anti-jamming structure applied to a hydraulic rock drill, characterized in that, It includes a piston (3), a cylinder (2) and a reversing valve (1). The piston (3) and the reversing valve (1) are coaxially arranged in the cylinder (2). The reversing valve (1) is located between the piston (3) and the cylinder (2). The reversing valve (1) is used to assist the piston (3) in reversing. The cylinder (2) and piston (3) are provided with a brake dead chamber (4), a piston rear chamber (7) for oil inlet and a piston front chamber (6); The reversing valve (1) is provided with an anti-jamming part (11) protruding towards the piston (3), and the piston (3) is provided with a relief groove (31) recessed towards the center of the piston (3). The anti-jamming part (11) cooperates with the relief groove (31) to prevent the piston (3) from getting stuck in the brake dead chamber (4). The two ends of the relief groove (31) form steps with the outer peripheral wall of the piston (3); the steps at both ends of the relief groove (31) are provided with buffer parts (32), and the surface of the buffer parts (32) is an inclined surface; there is a gap between the lower end of the anti-jamming part (11) and the bottom of the relief groove (31), so that the oil can smoothly act on the anti-jamming part (11) and the steps of the relief groove (31) to generate force, thereby enabling the reversing valve (1) to exert a better pushing force on the piston (3). Through this gap, the oil is prevented from being blocked in the piston rear chamber (7).

2. The anti-jamming structure according to claim 1, characterized in that, The reversing valve (1) has a braking part (12) on its outer peripheral wall, and a valve braking chamber (5) that cooperates with the braking part (12) is provided between the cylinder (2) and the reversing valve (1).

3. The anti-jamming structure according to claim 2, characterized in that, The braking part (12) is a protrusion that protrudes toward the cylinder (2); There is an oil outlet gap (14) between the top of the brake unit (12) and the cylinder (2).

4. The anti-jamming structure according to claim 1, characterized in that, The reversing valve (1) has at least one buoyancy groove (13) on its outer peripheral wall; The buoyancy groove (13) is recessed toward the center of the piston (3).

5. The anti-jamming structure according to claim 4, characterized in that, The radial depth of the buoyancy groove (13) is 1 to 4 mm.

6. The anti-jamming structure according to claim 1, characterized in that, The radial depth of the relief groove (31) is 1 to 2 mm.

7. The anti-jamming structure according to claim 1, characterized in that, The bottom of the anti-jamming part (11) is flat.

8. A hydraulic rock drill, characterized in that, The hydraulic rock drill includes the anti-jamming structure described in any one of claims 1 to 7.

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