The Sleeve Valve Type Impact Cylinder Structure of a Fully Hydraulic Rock Drill

Abstract

The present invention provides a sleeve valve type impact cylinder structure for a full hydraulic rock drill, which includes an impact cylinder body, an impact piston and a control valve. A main oil inlet and an oil return port are arranged on the impact cylinder body. A front cylinder sleeve and a rear cylinder sleeve are fixedly installed in the inner cavity of the impact cylinder body. A front oil inlet is arranged on the front cylinder sleeve, and a rear oil inlet is arranged on the rear cylinder sleeve. The control valve is installed in the inner holes of the front cylinder sleeve and the rear cylinder sleeve. The impact piston is inserted into the valve hole of the control valve. A hydraulic control oil circuit is arranged between the control valve and the impact piston, and the hydraulic control oil circuit can drive the impact piston to move left and right. Through the sleeve valve design, the structural form of the impact cylinder is simplified, the control valve is located between the impact cylinder and the impact piston, and most of the stepped holes and oil grooves are transferred to the front cylinder sleeve and the rear cylinder sleeve. These two parts have good processability, effectively improving the product life, facilitating maintenance and having a lower maintenance cost.

Description

Technical Field

[0001] The present invention relates to a sleeve valve type impact cylinder structure of a full hydraulic rock drill. Background Art

[0002] At present, most of the valve oil distribution type hydraulic rock drills designed in the domestic market adopt a separate design of the control valve and the impact chamber. Although this design has small internal leakage and low oil consumption, due to the independent design of the external valve, the structure is relatively complex and the overall weight is large. Especially in the domestic market, due to factors such as processing accuracy and oil cleanliness, the service life of the rock drill is not high, generally less than 1000 hours, far lower than that of imported rock drills from abroad. Moreover, the impact chamber of the impact cylinder of the external valve structure is a multi-stage stepped hole, and the cylindricity and coaxiality requirements of the stepped hole are relatively high, which is difficult to guarantee in terms of process. It is difficult to form an effective oil film between the impact piston and the impact chamber, and it cannot be in a floating state, often resulting in cylinder pulling phenomenon. Summary of the Invention

[0003] The technical problem to be solved by the present invention is that most of the valve oil distribution type hydraulic rock drills designed in the domestic market adopt a separate design of the control valve and the impact chamber, with a relatively complex structure, a large overall weight, and high processing difficulty. The present invention provides a sleeve valve type impact cylinder structure of a full hydraulic rock drill to solve the above problems.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a sleeve valve type impact cylinder structure of a full hydraulic rock drill, including an impact cylinder body, an impact piston, and a control valve. A main oil inlet and an oil return port are provided on the impact cylinder body. A front cylinder sleeve and a rear cylinder sleeve are fixedly installed in the inner cavity of the impact cylinder body. The front cylinder sleeve and the rear cylinder sleeve are collinear. A forward oil inlet is provided on the front cylinder sleeve, and a rearward oil inlet is provided on the rear cylinder sleeve. The forward oil inlet and the rearward oil inlet are both connected to the main oil inlet. The control valve is installed in the inner holes of the front cylinder sleeve and the rear cylinder sleeve and can move left and right in the inner holes of the front cylinder sleeve and the rear cylinder sleeve. The impact piston is inserted into the valve hole of the control valve, and a hydraulic control oil circuit is provided between the control valve and the impact piston. The hydraulic control oil circuit can drive the impact piston to move left and right.

[0005] Furthermore: The hydraulic control oil circuit includes a first oil passage and a second oil passage. A valve seat is installed at the right part of the inner hole of the rear cylinder sleeve. A first installation groove recessed axially inward is provided on the left end face of the rear cylinder sleeve. A limiting snap ring protruding radially outward is provided in the middle of the control valve. The limiting snap ring is slidably arranged in the first installation groove, and the outer wall of the limiting snap ring is hermetically arranged with the groove wall of the first installation groove. Control steps and pressure steps protruding outward circumferentially are arranged at intervals in the middle of the impact piston. The outer walls of the control steps and the pressure steps are hermetically arranged with the hole wall of the valve hole. The left pressure surface area of the pressure step is smaller than the right pressure surface area. In the valve hole, the space on the right side of the right pressure surface is the right pressure chamber, and in the valve hole, the space on the left side of the left pressure surface is the left pressure chamber. A first oil return groove is provided at the bottom of the first installation groove. One end of the first oil return groove is communicated with the oil return port, and the other end of the first oil return groove is communicated with the valve hole through a third oil passage. A second oil return groove is provided on the rear cylinder sleeve. One end of the second oil return groove is communicated with the oil return port. A fourth oil passage communicated with the valve hole is provided on the control valve. A connection port is also provided on the control valve. Oil can flow between the left pressure chamber and the left end face of the limiting snap ring through the connection port. When the control valve moves to the left position, the left end face of the limiting snap ring abuts against the right end face of the front cylinder sleeve, and the right end of the control valve is far away from the valve seat to form the first oil passage. The rear oil inlet is communicated with the right pressure chamber through the first oil passage. At the same time, the fourth oil passage is far away from the second oil return groove and is disconnected from the second oil return groove. When the control valve moves to the right position, the right end face of the control valve abuts against the valve seat, the first oil passage is closed, and at the same time, the fourth oil passage is communicated with the second oil return groove. When the impact piston moves to the left position, the control step is far away from the valve hole to form the second oil passage. The front oil inlet is communicated with the left pressure chamber through the second oil passage. At the same time, the pressure step abuts against the third oil passage, the pressure step is far away from the fourth oil passage, and the fourth oil passage is communicated with the right pressure chamber. When the impact piston moves to the right position, the outer wall of the control step is hermetically arranged with the hole wall of the valve hole, the second oil passage is closed, and at the same time, the side wall of the pressure step abuts against the fourth oil passage, the pressure step is far away from the connection port, and the connection port is communicated with the third oil passage through the left pressure chamber.

[0006] Further: A support sleeve is provided on the right side of the rear cylinder liner. The support sleeve is fixedly installed in the inner cavity of the impact cylinder block. The right part of the impact piston is installed in the inner hole of the support sleeve and can move axially in the inner hole of the support sleeve. The outer wall of the impact piston is hermetically arranged with the inner hole wall of the support sleeve. A second installation groove recessed axially inward is provided on the left end face of the front cylinder liner. A guide sleeve is installed in the second installation groove. The left part of the impact piston is installed in the inner hole of the guide sleeve and can move axially in the inner hole of the guide sleeve.

[0007] The beneficial effect of the present invention is that the sleeve valve type impact cylinder structure of the full hydraulic rock drill of the present invention simplifies the structural form of the impact cylinder through the sleeve valve design structure, makes the control valve located between the impact cylinder and the impact piston, transfers most of the stepped holes and oil grooves to the front cylinder liner and the rear cylinder liner, and these two parts have good processability, effectively improving the product life, and being convenient for maintenance with low maintenance cost. Description of the Drawings

[0008] The present invention will be further described below with reference to the drawings and embodiments.

[0009] Figure 1 is a structural schematic diagram of the sleeve valve type impact cylinder structure of the full hydraulic rock drill of the present invention;

[0010] Figure 2 is a structural schematic diagram of the impact piston installed in the control valve;

[0011] Figure 3 is a structural schematic diagram of the impact piston;

[0012] Figure 4 is a structural schematic diagram of the starting state of the return stroke;

[0013] Figure 5 is a structural schematic diagram during the process of the return stroke back to zero;

[0014] Figure 6 is a structural schematic diagram of the starting state of the forward strike;

[0015] Figure 7 is a structural schematic diagram of the ending state of the forward strike.

[0016] In the figure: 1. Impact cylinder block; 2. Impact piston; 3. Control valve; 30. Valve hole; 4. Main oil inlet; 5. Oil return port; 6. Front cylinder sleeve; 7. Rear cylinder sleeve; 8. Front oil inlet; 9. Rear oil inlet; 10. First oil passage; 11. Second oil passage; 12. Valve seat; 13. First installation groove; 14. Limit clamping platform; 15. Control step; 16. Pressure step; 17. Right pressure chamber; 18. Left pressure chamber; 19. First oil return groove; 20. Third oil passage; 21. Second oil return groove; 22. Fourth oil passage; 23. Connection port; 24. Support sleeve; 25. Guide sleeve. Detailed implementation mode

[0017] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention. On the contrary, the embodiments of the present invention include all changes, modifications and equivalents falling within the spirit and scope of the appended claims.

[0018] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0019] In addition, the terms "first", "second", etc. are only used for descriptive purposes and should not be construed as indicating or implying relative importance. In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise stated, the meaning of "a plurality" is two or more.

[0020] Any process or method description depicted in a flowchart or otherwise described herein can be understood to represent a module, segment, or portion of code including one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present invention includes additional implementations where functions may be performed in a substantially simultaneous manner or in a reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0021] As Figure 1 and Figure 2 shown, the present invention provides a sleeve valve type impact cylinder structure for a full hydraulic rock drill, which includes an impact cylinder body 1, an impact piston 2, and a control valve 3. A main oil inlet 4 and an oil return port 5 are provided on the impact cylinder body 1. A front cylinder sleeve 6 and a rear cylinder sleeve 7 are fixedly installed in the inner cavity of the impact cylinder body 1. The front cylinder sleeve 6 and the rear cylinder sleeve 7 are collinear. A forward oil inlet 8 is provided on the front cylinder sleeve 6, and a rearward oil inlet 9 is provided on the rear cylinder sleeve 7. Both the forward oil inlet 8 and the rearward oil inlet 9 are communicated with the main oil inlet 4. The control valve 3 is installed in the inner holes of the front cylinder sleeve 6 and the rear cylinder sleeve 7 and can move left and right in the inner holes of the front cylinder sleeve 6 and the rear cylinder sleeve 7. The impact piston 2 is inserted into the valve hole 30 of the control valve 3. A hydraulic control oil circuit is provided between the control valve 3 and the impact piston 2, and the hydraulic control oil circuit can drive the impact piston 2 to move left and right.

[0022] The sleeve valve design structure of this solution simplifies the structural form of the impact cylinder, makes the control valve 3 located between the impact cylinder and the impact piston 2. In the sleeve valve design structure, the stepped hole is transferred to the control valve 3, the front cylinder sleeve 6, and the rear cylinder sleeve 7. These two parts have good processability, thus effectively improving the product life, being convenient for maintenance, and having a lower maintenance cost.

[0023] Combined with Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 and Figure 7As shown, the hydraulic control oil circuit includes a first oil passage 10 and a second oil passage 11. A valve seat 12 is installed at the right part of the inner hole of the rear cylinder sleeve 7. A first installation groove 13 concave axially inward is provided on the left end face of the rear cylinder sleeve 7. A limiting clamping platform 14 protruding radially outward is provided in the middle of the control valve 3. The limiting clamping platform 14 is slidably arranged in the first installation groove 13, and the outer wall of the limiting clamping platform 14 is hermetically arranged with the groove wall of the first installation groove 13. At the middle part of the impact piston 2, a control step 15 and a pressure step 16 protruding outward circumferentially are arranged at intervals. The outer walls of the control step 15 and the pressure step 16 are both hermetically arranged with the hole wall of the valve hole 30. The left pressure surface area of the pressure step 16 is smaller than the right pressure surface area. In the valve hole 30, the space on the right side of the right pressure surface is the right pressure chamber 17. In the valve hole 30, the space on the left side of the left pressure surface is the left pressure chamber 18. A first oil return groove 19 is provided at the bottom of the first installation groove 13. One end of the first oil return groove 19 is communicated with the oil return port 5, and the other end of the first oil return groove 19 is communicated with the valve hole 30 through a third oil passage 20. A second oil return groove 21 is provided on the rear cylinder sleeve 7. One end of the second oil return groove 21 is communicated with the oil return port 5. A fourth oil passage 22 communicated with the valve hole 30 is provided on the control valve 3. A connection port 23 is also provided on the control valve 3. Oil can flow between the left pressure chamber 18 and the left end face of the limiting clamping platform 14 through the connection port 23.

[0024] When the control valve 3 moves to the left position, the left end face of the limiting clamping platform 14 abuts against the right end face of the front cylinder sleeve 6. The right end of the control valve 3 is far away from the valve seat 12 to form the first oil passage 10. The rear oil inlet 9 is communicated with the right pressure chamber 17 through the first oil passage 10. At the same time, the fourth oil passage 22 is far away from the second oil return groove 21 and is disconnected from the second oil return groove 21.

[0025] When the control valve 3 moves to the right position, the right end face of the control valve 3 abuts against the valve seat 12, and the first oil passage 10 is closed. At the same time, the fourth oil passage 22 is communicated with the second oil return groove 21.

[0026] When the impact piston 2 moves to the left position, the control step 15 is far away from the valve hole 30 to form the second oil passage 11. The front oil inlet 8 is communicated with the left pressure chamber 18 through the second oil passage 11. At the same time, the pressure step 16 abuts against the third oil passage 20. The pressure step 16 is far away from the fourth oil passage 22, and the fourth oil passage 22 is communicated with the right pressure chamber 17.

[0027] When the impact piston 2 moves to the right position, the outer wall of the control step 15 is hermetically arranged with the wall of the valve hole 30, the second oil passage 11 is closed, and at the same time, the side wall of the pressure step 16 abuts against the fourth oil passage 22, the pressure step 16 is far away from the connection port 23, and the connection port 23 is communicated with the third oil passage 20 through the left pressure chamber 18.

[0028] During operation, the control valve 3 and the impact piston 2 are controlled to move between the left position and the right position through a hydraulic control oil circuit, so that the impact piston 2 cycles among four states:

[0029] S1 Return start: At this time, the impact piston 2 is in the left position, the control valve 3 is in the right position, the second oil passage 11 is opened, the first oil passage 10 is closed, oil is continuously injected into the left pressure chamber 18 to form pressure on the left pressure surface of the pressure step 16, and the oil in the right pressure chamber 17 flows out from the oil return port 5 through the fourth oil passage 22 and the second oil return groove 21, and the return starts;

[0030] S2 Return to zero position: The impact piston 2 returns to the right position under the action of pressure, the control valve 3 is still in the right position, both the first oil passage 10 and the second oil passage 11 are closed, and the oil entering from the rear oil inlet 9 forms pressure on the right end face of the control valve 3 and pushes the control valve 3 to move leftward;

[0031] S3 Forward impact start: When the control valve 3 moves to the left position, the first oil passage 10 is opened, and at the same time, the side wall of the pressure step 16 abuts against the fourth oil passage 22, the right pressure chamber 17 is disconnected from the fourth oil passage 22, and the pressure of the injected oil on the right pressure surface of the pressure step 16 continuously increases, so as to push the impact piston 2 to start moving leftward for forward impact;

[0032] S4 Forward impact end: When the impact piston 2 moves to the left position, the oil entering from the front oil inlet 8 forms pressure on the left end face of the control valve 3, and the oil in the left pressure chamber 18 enters the left end face of the limit clamping platform 14 through the connection port 23 to form pressure, and the two pressures simultaneously push the control valve 3 to move rightward.

[0033] A support sleeve 24 is arranged on the right side of the rear cylinder sleeve 7, the support sleeve 24 is fixedly installed in the inner cavity of the impact cylinder block 1, the right part of the impact piston 2 is installed in the inner hole of the support sleeve 24 and can axially move in the inner hole of the support sleeve 24, and the outer wall of the impact piston 2 is hermetically arranged with the wall of the inner hole of the support sleeve 24; a second installation groove concave axially inward is arranged on the left end face of the front cylinder sleeve 6, a guide sleeve 25 is installed in the second installation groove, the left part of the impact piston 2 is installed in the inner hole of the guide sleeve 25 and can axially move in the inner hole of the guide sleeve 25. This way of supporting both ends of the impact piston 2 can ensure the stability of the impact piston 2 during movement.

[0034] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0035] Based on the above inspiration from the ideal embodiments of the present invention, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. Sleeve valve type impact cylinder structure of a full hydraulic rock drill, comprising an impact cylinder body (1), an impact piston (2) and a control valve (3). A main oil inlet (4) and an oil return port (5) are arranged on the impact cylinder body (1). It is characterized in that: A front cylinder sleeve (6) and a rear cylinder sleeve (7) are fixedly installed in the inner cavity of the impact cylinder body (1). The front cylinder sleeve (6) and the rear cylinder sleeve (7) are arranged collinearly. A front oil inlet (8) is arranged on the front cylinder sleeve (6), and a rear oil inlet (9) is arranged on the rear cylinder sleeve (7). The front oil inlet (8) and the rear oil inlet (9) are both communicated with the main oil inlet (4). The control valve (3) is installed in the inner holes of the front cylinder sleeve (6) and the rear cylinder sleeve (7) and can move left and right in the inner holes of the front cylinder sleeve (6) and the rear cylinder sleeve (7). The impact piston (2) is inserted into the valve hole (30) of the control valve (3). A hydraulic control oil circuit is arranged between the control valve (3) and the impact piston (2), and the hydraulic control oil circuit can drive the impact piston (2) to move left and right. The hydraulic control oil circuit comprises a first oil passage (10) and a second oil passage (11). A valve seat (12) is installed at the right part of the inner hole of the rear cylinder sleeve (7). A first installation groove (13) concave axially inward is arranged on the left end face of the rear cylinder sleeve (7). A limiting clamping platform (14) protruding radially outward is arranged in the middle of the control valve (3). The limiting clamping platform (14) is slidably arranged in the first installation groove (13), and the outer wall of the limiting clamping platform (14) is hermetically arranged with the groove wall of the first installation groove (13). Control steps (15) and pressure steps (16) protruding circumferentially outward are arranged at intervals in the middle of the impact piston (2). The outer walls of the control steps (15) and the pressure steps (16) are both hermetically arranged with the hole wall of the valve hole (30). The left pressure surface area of the pressure step (16) is smaller than the right pressure surface area. In the valve hole (30), the space on the right side of the right pressure surface is the right pressure chamber (17), and in the valve hole (30), the space on the left side of the left pressure surface is the left pressure chamber (18). A first oil return groove (19) is arranged at the bottom of the first installation groove (13). One end of the first oil return groove (19) is communicated with the oil return port (5), and the other end of the first oil return groove (19) is communicated with the valve hole (30) through a third oil passage (20). A second oil return groove (21) is arranged on the rear cylinder sleeve (7). One end of the second oil return groove (21) is communicated with the oil return port (5). A fourth oil passage (22) communicated with the valve hole (30) is arranged on the control valve (3). A connection port (23) is also arranged on the control valve (3), and oil fluid can flow between the left pressure chamber (18) and the left end face of the limiting clamping platform (14) through the connection port (23). When the control valve (3) moves to the left position, the left end face of the limit clamping table (14) abuts against the right end face of the front cylinder sleeve (6). The right end of the control valve (3) moves away from the valve seat (12) to form the first oil passage (10). The rear oil inlet (9) is communicated with the right pressure chamber (17) through the first oil passage (10). At the same time, the fourth oil passage (22) moves away from the second oil return groove (21) and is disconnected from the second oil return groove (21). When the control valve (3) moves to the right position, the right end face of the control valve (3) abuts against the valve seat (12). The first oil passage (10) is closed. At the same time, the fourth oil passage (22) is communicated with the second oil return groove (21). When the impact piston (2) moves to the left position, the control step (15) moves away from the valve hole (30) to form the second oil passage (11). The front oil inlet (8) is communicated with the left pressure chamber (18) through the second oil passage (11). At the same time, the pressure step (16) abuts against the third oil passage (20). The pressure step (16) moves away from the fourth oil passage (22). The fourth oil passage (22) is communicated with the right pressure chamber (17). When the impact piston (2) moves to the right position, the outer wall of the control step (15) is hermetically arranged with the hole wall of the valve hole (30). The second oil passage (11) is closed. At the same time, the side wall of the pressure step (16) abuts against the fourth oil passage (22). The pressure step (16) moves away from the connection port (23). The connection port (23) is communicated with the third oil passage (20) through the left pressure chamber (18). A support sleeve (24) is arranged on the right side of the rear cylinder sleeve (7). The support sleeve (24) is fixedly installed in the inner cavity of the impact cylinder block (1).

2. The sleeve valve type impact cylinder structure of the full hydraulic rock drill according to claim 1, characterized in that: The right part of the impact piston (2) is installed in the inner hole of the support sleeve (24) and can axially move in the inner hole of the support sleeve (24). The outer wall of the impact piston (2) is hermetically arranged with the inner hole wall of the support sleeve (24). A second installation groove recessed axially inward is arranged on the left end face of the front cylinder sleeve (6). A guide sleeve (25) is installed in the second installation groove. The left part of the impact piston (2) is installed in the inner hole of the guide sleeve (25) and can axially move in the inner hole of the guide sleeve (25).

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