Hydraulic oil front sealing structure of hydraulic rock drill

Abstract

The utility model discloses a hydraulic oil front sealing structure of a hydraulic rock drill. The hydraulic oil front sealing structure comprises a front sealing guide sleeve embedded in a containing space formed by a cylinder sleeve, a piston front guide sleeve and a middle body. The impact piston is coaxially arranged in the cylinder sleeve and the middle body in a sliding manner and penetrates through the piston front guide sleeve and the front sealing guide sleeve; a plurality of step seals for preventing hydraulic oil in the cylinder sleeve from leaking are embedded between the main sleeve body section of the front sealing guide sleeve and the impact piston; and an oil seal for isolating hydraulic oil in the cylinder sleeve from gas in the intermediate is clamped between the head of the front sealing guide sleeve and the impact piston. A step sealing and oil sealing dual-sealing structure is arranged between the front sealing guide sleeve and the piston, so that the oil and gas isolation effect is improved.

Description

Technical Field

[0001] The utility model relates to a front sealing structure of hydraulic oil for a hydraulic rock drill, belonging to the technical fields of hydraulic rock drills and sealing technologies. Background Art

[0002] A rock drill works according to the impact and crushing principle. During operation, the impact piston makes high-frequency reciprocating motions and continuously impacts the shank end. Under the action of the impact force, the head of the shank end crushes the rock and drills into a certain depth, forming a dent. After the impact piston retracts, the shank end rotates by a certain angle. When the piston moves forward and impacts the shank end again, a new dent is formed. The fan-shaped rock block between the two dents is sheared by the horizontal component force generated on the shank end. The impact piston continuously impacts the shank end, and compressed air or pressure water is continuously input from the central hole of the shank end to discharge the rock slag out of the hole, thus forming a circular drill hole with a certain depth.

[0003] The impact action of the impact piston needs to be controlled by hydraulic oil. Since the impact piston and the shank end are located in different sections of the machine body, it is necessary to prevent the hydraulic oil driving the impact piston from leaking into the space accommodating the shank end. At the same time, it is also necessary to prevent the gas for cooling the shank end from entering the chamber accommodating the hydraulic oil. Therefore, a front sealing structure is required to seal the transition part.

[0004] The existing sealing structure for isolating hydraulic oil and cooling gas is to set a Step seal between the front sealing guide sleeve and the impact piston to achieve the isolation of oil and gas through the Step seal. However, during the use of the equipment, the isolation effect of the Step seal on the cooling gas is not very satisfactory, and once the Step seal is worn, a gap will be generated between it and the impact piston, resulting in hydraulic oil leakage. Content of the Utility Model

[0005] The purpose of the utility model is to provide a front sealing structure of hydraulic oil for a hydraulic rock drill, which improves the effect of isolating oil and gas by setting a double sealing structure of Step seal and oil seal between the front sealing guide sleeve and the piston.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0007] A front sealing structure of hydraulic oil for a hydraulic rock drill includes a front sealing guide sleeve embedded in the accommodation space formed by a cylinder liner, a piston front guide sleeve and an intermediate body; an impact piston is coaxially and slidably arranged in the cylinder liner and the intermediate body and penetrates through the piston front guide sleeve and the front sealing guide sleeve;

[0008] A plurality of Step seals for preventing the hydraulic oil in the cylinder liner from leaking are embedded between the main sleeve body section of the front sealing guide sleeve and the impact piston; an oil seal for isolating the hydraulic oil in the cylinder liner from the gas in the intermediate body is clamped between the head of the front sealing guide sleeve and the impact piston.

[0009] Preferably, the head of the cylinder liner is inserted into the tail of the intermediate body and abuts against the stepped surface in the inner cavity of the tail of the intermediate body;

[0010] The piston front guide sleeve and the front seal guide sleeve are sequentially embedded in the inner cavity of the head of the cylinder liner from the rear to the front; and the tail of the piston front guide sleeve abuts against the inner cavity body of the cylinder liner; the head of the front seal guide sleeve also abuts against the stepped surface in the inner cavity of the tail of the intermediate body, and the tail abuts against the head of the piston front guide sleeve.

[0011] Preferably, an inwardly recessed annular groove is formed on the outer peripheral body of the oil seal;

[0012] The head of the front seal guide sleeve is formed with a mounting portion for embedding the oil seal and a converging portion for inserting into the upper annular groove of the oil seal.

[0013] Preferably, a leakage oil cavity is formed between the piston front guide sleeve, the front seal guide sleeve and the cylinder liner for accommodating the hydraulic oil leaking from the abutting surface between the piston front guide sleeve and the front seal guide sleeve.

[0014] Preferably, first sealing rings are respectively arranged at the abutting surfaces between the piston front guide sleeve and the cylinder liner and between the front seal guide sleeve and the cylinder liner.

[0015] Preferably, an annular transition oil cavity communicating with the leakage oil channel of the hydraulic rock drill is formed radially between the head of the cylinder liner and the intermediate body, and the transition oil cavity is communicated with the leakage oil cavity for leading out the hydraulic oil in the leakage oil cavity.

[0016] Preferably, a plurality of leakage oil holes are formed around the head of the cylinder liner, and the transition oil cavity is communicated with the leakage oil cavity through the leakage oil holes.

[0017] Preferably, second sealing rings are respectively arranged at the abutting surfaces between the cylinder liner and the intermediate body on both sides of the transition oil cavity.

[0018] The beneficial effects of the present utility model are as follows:

[0019] 1. By respectively arranging a Struthers seal and an oil seal in the front seal guide sleeve and at the head, the oil-gas isolation effect can be improved; at the same time, after a gap is generated between the Struthers seal and the impact piston due to wear, the oil seal can be used to further prevent the leakage of hydraulic oil;

[0020] 2. By arranging a leakage oil cavity and a transition oil cavity, the leaked hydraulic oil can be led out of the machine body; at the same time, the first sealing ring and the second sealing ring can be used to prevent the interference of the oil circuit in the machine body and can further isolate the oil and gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a cross-sectional view of the front seal structure;

[0022] Figure 2 It is another cross-sectional view of the front seal structure;

[0023] Figure 3 Cross-sectional view of the piston front guide sleeve and the front seal guide sleeve;

[0024] Figure 4 Cross-sectional view of the intermediate body;

[0025] Figure 5 Cross-sectional view of the front seal guide sleeve;

[0026] Figure 6 Schematic diagram of the oil seal;

[0027] Figure 7 Cross-sectional view of the hydraulic rock drill with the front seal structure.

[0028] The meanings of the main reference numerals in the figure are as follows:

[0029] 1. Cylinder liner, 2. Cylinder block, 3. Piston front guide sleeve, 4. Intermediate body, 5. Front seal guide sleeve, 6. Impact piston, 7. Strseal, 8. Oil seal, 9. Ring groove, 10. Installation part, 11. Converging part, 12. Leakage oil cavity, 13. Transition oil cavity, 14. Leakage oil hole, 15. Leakage oil passage, 16. First sealing ring, 17. Second sealing ring. Specific embodiments

[0030] The following specifically introduces the present utility model in conjunction with the drawings and embodiments.

[0031] This embodiment provides a front seal structure for the hydraulic oil of a hydraulic rock drill, as Figure 1-7 shown, including a front seal guide sleeve 5 embedded in the accommodation space formed by the cylinder liner 1 (installed in the cylinder block 2), the piston front guide sleeve 3, and the intermediate body 4. Specifically, the head of the cylinder liner 1 is inserted into the tail of the intermediate body 4 and abuts against the stepped surface in the inner cavity of the tail of the intermediate body 4; the piston front guide sleeve 3 and the front seal guide sleeve 5 are sequentially embedded in the inner cavity of the head in the cylinder liner 1 from back to front; and the tail of the piston front guide sleeve 3 abuts against the inner cavity of the cylinder liner 1; the head of the front seal guide sleeve 5 also abuts against the stepped surface in the inner cavity of the tail of the intermediate body 4, and the tail abuts against the head of the piston front guide sleeve 3. The impact piston 6 is coaxially slidably arranged in the cylinder liner 1 and the intermediate body 4 and penetrates through the piston front guide sleeve 3 and the front seal guide sleeve 5.

[0032] There are two Struthers seals 7 embedded between the main sleeve body section of the front seal guide sleeve 5 and the impact piston 6 to prevent the hydraulic oil in the cylinder sleeve 1 from leaking; a oil seal 8 for isolating the hydraulic oil in the cylinder sleeve 1 from the gas in the intermediate body 4 is clamped between the head of the front seal guide sleeve 5 and the impact piston 6. An inwardly recessed annular groove 9 is formed on the outer peripheral body of the oil seal 8; the head of the front seal guide sleeve 5 is formed with a mounting portion 10 for the oil seal 8 to be embedded and a converging portion 11 inserted into the annular groove 9 on the oil seal 8. Through the double guarantee of the Struthers seal 7 and the oil seal 8, the oil-gas isolation effect is improved; at the same time, after the Struthers seal 7 wears and a gap is generated between it and the impact piston 6, the oil seal 8 can be used to further prevent the hydraulic oil from leaking into the intermediate body 4.

[0033] When the impact piston 6 is operating, part of the hydraulic oil will leak through the gap between the piston front guide sleeve 3 and the front seal guide sleeve 5 into the gap between the piston front guide sleeve 3, the front seal guide sleeve 5 and the cylinder sleeve 1. In order to lead out the leaked hydraulic oil from the body, a leakage oil cavity 12 for accommodating the leaked hydraulic oil is formed between the piston front guide sleeve 3, the front seal guide sleeve 5 and the cylinder sleeve 1. Further, an annular transition oil cavity 13 communicating with the leakage oil passage 15 of the hydraulic rock drill is formed radially between the head of the cylinder sleeve 1 and the intermediate body 4. A plurality of leakage oil holes 14 are circumferentially formed in the head of the cylinder sleeve 1. The transition oil cavity 13 is communicated with the leakage oil cavity 12 through the leakage oil holes 14. Therefore, the hydraulic oil in the leakage oil cavity 12 can enter the transition oil cavity 13 through the leakage oil holes 14 and then be led out of the body through the leakage oil passage 15 of the hydraulic rock drill.

[0034] At the same time, in order to further improve the sealing effect, prevent interference between oil circuits and further isolate oil and gas, first sealing rings 16 for preventing the hydraulic oil in the leakage oil cavity 12 from flowing out and preventing the hydraulic oil in the cylinder sleeve 1 from directly entering the leakage oil cavity 12 are respectively arranged at the abutting surfaces of the piston front guide sleeve 3 and the cylinder sleeve 1 and at the abutting surfaces of the front seal guide sleeve 5 and the cylinder sleeve 1. Second sealing rings 17 for preventing the hydraulic oil in the transition oil cavity 13 from leaking are respectively arranged at the abutting surfaces of the cylinder sleeve 1 and the intermediate body 4 on both sides of the transition oil cavity 13. Moreover, the first sealing ring 16 between the front seal guide sleeve 5 and the cylinder sleeve 1 and the second sealing ring 17 at the abutting surface of the cylinder block 2 and the intermediate body 4 on the front side of the transition oil cavity 13 can also prevent the gas in the intermediate body from entering the rear side space, further improving the oil-gas isolation effect.

[0035] The above is only the preferred embodiment of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the principle of the utility model patent, several improvements and retouches can be made, and these improvements and retouches should also be regarded as the protection scope of the utility model patent.

Claims

1. A hydraulic oil front sealing structure for a hydraulic rock drill, characterized in that: It includes a front sealing guide sleeve embedded in the accommodating space formed by the cylinder sleeve, the piston front guide sleeve and the intermediate body; the impact piston is coaxially slidably arranged in the cylinder sleeve and the intermediate body and penetrates the piston front guide sleeve and the front sealing guide sleeve; A plurality of step seals are embedded between the main sleeve section of the front sealing guide sleeve and the impact piston to prevent leakage of hydraulic oil in the cylinder sleeve; an oil seal is clamped between the head of the front sealing guide sleeve and the impact piston to isolate the hydraulic oil in the cylinder sleeve and the gas in the intermediate body.

2. The hydraulic oil front sealing structure of the hydraulic rock drill according to claim 1, characterized in that: The head of the cylinder sleeve is inserted into the tail of the intermediate body and abuts against the stepped surface in the inner cavity of the tail of the intermediate body; The piston leading guide sleeve and the front sealing guide sleeve are sequentially embedded in the head inner cavity of the cylinder sleeve from back to front; and the tail of the piston leading guide sleeve abuts against the inner cavity of the cylinder sleeve; the head of the front sealing guide sleeve also abuts against the stepped surface in the tail inner cavity of the intermediate body, and the tail abuts against the head of the piston leading guide sleeve.

3. The hydraulic oil front sealing structure of a hydraulic rock drill according to any one of claims 1 or 2, characterized in that: An inwardly recessed annular groove is formed on the outer peripheral body of the oil seal; The head of the front sealing guide sleeve is formed with a mounting portion for embedding the oil seal and a gathering portion inserted into the upper ring groove of the oil seal.

4. The hydraulic oil front sealing structure of the hydraulic rock drill according to claim 2, characterized in that: A leakage oil chamber for accommodating hydraulic oil leaking from the abutment surface between the piston front guide sleeve and the front sealing guide sleeve is formed between the piston front guide sleeve, the front sealing guide sleeve and the cylinder sleeve.

5. The hydraulic oil front sealing structure of the hydraulic rock drill according to claim 4, characterized in that: A first sealing ring is respectively arranged at the abutting surface between the piston front guide sleeve and the cylinder sleeve and at the abutting surface between the front sealing guide sleeve and the cylinder sleeve.

6. The hydraulic oil front sealing structure of the hydraulic rock drill according to claim 4, characterized in that: An annular transition oil chamber connected to the leakage oil channel of the hydraulic rock drill is formed radially between the head and the intermediate body of the cylinder sleeve. The transition oil chamber is connected to the leakage oil chamber and is used to guide the hydraulic oil in the leakage oil chamber.

7. The hydraulic oil front sealing structure of the hydraulic rock drill according to claim 6, characterized in that: A plurality of leakage oil holes are arranged around the head of the cylinder sleeve, and the transition oil chamber is connected with the leakage oil chamber through the leakage oil holes.

8. The hydraulic oil front sealing structure of the hydraulic rock drill according to claim 6, characterized in that: Second sealing rings are respectively arranged at the abutting surfaces of the cylinder sleeve and the intermediate body located on both sides of the transition oil chamber.

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