1. The utility model provides a buffer gear for hydraulic rock drill, includes the casing that has the cushion cylinder, its characterized in that: a drill rod (1), a thrust collar (2) and a buffer piston (3) are sequentially arranged in the shell from front to back; the thrust ring (2) is sleeved at the rear end of the drill rod (1) and used for limiting the backward axial displacement of the drill rod (1); the buffer piston (3) is arranged at the front end of the buffer cylinder which is provided with an annular groove in a reciprocating motion way, and the buffer piston (3) closes the annular groove to form a buffer cavity (4); hydraulic fluid capable of pushing the buffer piston (3) to move forwards to abut against the thrust ring (2) is filled in the buffer cavity (4);

when the drill rod (1) rebounds, the drill rod stops moving backwards by impacting the thrust ring (2), and then the thrust ring (2) impacts the buffer piston (3) backwards; the damping piston (3) is moved backwards by pushing the hydraulic fluid out of the damping chamber (4) when subjected to a collision in order to damp the impact.

2. The buffer mechanism for the hydraulic rock drill according to claim 1, characterized in that the housing is formed with an oil inlet passage communicating with the buffer chamber (4), the oil inlet passage being used for injecting the hydraulic fluid into the buffer chamber (4).

3. A buffer gear for a hydraulic rock drill according to claim 1, characterized in that the housing is formed with an oil outlet passage communicating with the buffer chamber (4), the oil outlet passage being adapted to discharge the hydraulic fluid in the buffer chamber (4) when the buffer piston (3) is subjected to a collision.

4. The buffer mechanism for the hydraulic rock drill according to claim 2, wherein the oil inlet passage comprises a high pressure oil port (51) for injecting high pressure hydraulic fluid, a high pressure passage for receiving the high pressure hydraulic fluid, a damping hole (53) for depressurizing the high pressure hydraulic fluid to form secondary high pressure hydraulic fluid, and a buffer passage for receiving the secondary high pressure hydraulic fluid and injecting the secondary high pressure hydraulic fluid into the buffer chamber (4), which are sequentially communicated.

5. A buffer gear for a hydraulic rock drill according to claim 4, characterized in that the high-pressure passage comprises a first high-pressure passage (521) and a second high-pressure passage (522) which communicate in sequence in the direction of flow of the high-pressure hydraulic fluid; one end, far away from the second high-pressure passage (522), of the first high-pressure passage (521) is communicated with the high-pressure oil port (51); the damping hole (53) is formed at one end of the second high-pressure passage (522) away from the first high-pressure passage (521).

6. A buffer gear for a hydraulic rock drill according to claim 4, characterized in that the buffer channel comprises a first buffer channel (541) and a second buffer channel (542) which are in communication in sequence in the direction of flow of the secondary high-pressure hydraulic fluid; one end, far away from the second buffer channel (542), of the first buffer channel (541) is connected with the damping hole (53); one end, far away from the first buffer channel (541), of the second buffer channel (542) is communicated with the buffer cavity (4).

7. A damping mechanism for a hydraulic rock drill according to claim 1, characterized in that the damping cylinder is fitted with a percussion piston (6); the drill rod (1), the thrust collar (2), the buffer piston (3) and the impact piston (6) are coaxially arranged.

8. A buffer gear for a hydraulic rock drill according to any one of claims 1 to 7, characterized in that the front end wall of the annular groove is shallower than the rear end wall; the buffer piston (3) is used for sealing the outer wall of the annular groove to form a step so as to be attached to the annular groove;

when the hydraulic fluid is injected into the buffer chamber (4), the hydraulic fluid pushes the step to move forward; when the step is moved backwards, the hydraulic fluid is squeezed out of the buffer chamber (4).

Background

The hydraulic rock drill is a rock drill machine which uses high-pressure oil as power to drive a piston to impact a drill rod and is provided with an independent swing mechanism. The hydraulic rock drill controls the piston to reciprocate, and drives the drill rod to repeatedly impact the rock so as to realize the cutting function of the rock drill. The oil pressure is higher than the air pressure, and the working efficiency is higher as the oil pressure is higher than the air pressure and can reach more than 10 MPa. Although the hydraulic rock drill is similar to the pneumatic rock drill, the piston has smaller diameter, larger length and better waveform, thereby having the characteristics of high drilling speed, high impact power, large torque, high frequency and the like.

Because the hydraulic rock drill has the characteristic of high impact energy, the force of rebounding and impacting the rock drill after the drill strikes rocks is also larger. The existing hydraulic rock drill is not provided with a buffer mechanism, a rebounded drill bit shank directly impacts an impact piston, and the drill bit shank is very easy to damage in high-frequency high-strength hard impact.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a buffer mechanism for a hydraulic rock drill, which can effectively reduce the probability of drill rebound, impact and damage.

In order to solve the technical problems, the invention adopts the following technical scheme:

a buffer mechanism for a hydraulic rock drill comprises a shell with a buffer cylinder, wherein a drill rod, a thrust collar and a buffer piston are sequentially arranged in the shell from front to back; the thrust collar is sleeved at the rear end of the drill rod and used for limiting the backward axial displacement of the drill rod; the buffer piston is arranged at the front end of the buffer cylinder which is provided with an annular groove in a reciprocating motion mode, and the buffer piston closes the annular groove to form a buffer cavity; the buffer cavity is filled with hydraulic fluid capable of pushing the buffer piston to move forwards to abut against the thrust ring;

the drill bit stops moving backwards by impacting the thrust ring when rebounding, and then the thrust ring impacts the buffer piston backwards; the cushion piston is moved rearward to cushion the impact by forcing the hydraulic fluid out of the cushion chamber when the cushion piston is subjected to a collision.

Above-mentioned buffer gear for hydraulic rock drill, preferably, the casing is formed with the intercommunication the oil feed passageway of cushion chamber, the oil feed passageway be used for to pour into in the cushion chamber hydraulic fluid.

In the above buffer mechanism for hydraulic rock drill, preferably, the housing is formed with an oil outlet passage communicating with the buffer chamber, and the oil outlet passage is configured to discharge the hydraulic fluid in the buffer chamber when the buffer piston is subjected to collision.

Above-mentioned buffer gear for hydraulic rock drill, preferably, the oil feed passageway is including the high-pressure hydraulic fluid mouth that is used for pouring into high-pressure hydraulic fluid that communicates in proper order, be used for holding high-pressure hydraulic fluid's high-pressure passage, be used for with high-pressure hydraulic fluid steps down in order to form inferior high-pressure hydraulic fluid's damping hole, and be used for holding inferior high-pressure hydraulic fluid, and will inferior high-pressure hydraulic fluid pours into buffer passage in the cushion chamber.

In the above buffer mechanism for a hydraulic rock drill, preferably, the high-pressure passage includes a first high-pressure passage and a second high-pressure passage which are sequentially communicated in a flow direction of the high-pressure hydraulic fluid; one end of the first high-pressure passage, which is far away from the second high-pressure passage, is communicated with the high-pressure oil port; the damping hole is formed at one end, far away from the first high-pressure channel, of the second high-pressure channel.

In the above buffer mechanism for a hydraulic rock drill, preferably, the buffer channel includes a first buffer channel and a second buffer channel that are sequentially communicated in the flow direction of the secondary high-pressure hydraulic fluid; one end of the first buffer channel, which is far away from the second buffer channel, is connected with the damping hole; one end, far away from the first buffer channel, of the second buffer channel is communicated with the buffer cavity.

In the above buffer mechanism for a hydraulic rock drill, preferably, the buffer cylinder is provided with an impact piston; the drill rod, the thrust collar and the buffer piston are coaxially arranged with the impact piston.

In the above buffer mechanism for a hydraulic rock drill, preferably, the front end groove wall of the annular groove is shallower than the rear end groove wall; the buffer piston is used for sealing the outer wall of the annular groove to form a step so as to be attached to the annular groove;

when the hydraulic fluid is injected into the buffer chamber, the hydraulic fluid pushes the step to move forward; when the step moves backward, the hydraulic fluid is squeezed out of the buffer chamber.

Compared with the prior art, the invention has the advantages that:

different from the prior art, when a drill bit of a hydraulic rock drill without a buffer mechanism impacts an external structure to rebound, a drill bit shank and a shell are in rigid collision, and the drill bit shank is easy to damage. When the drill bit of the invention impacts an external structure and rebounds, the drill bit which axially moves backwards impacts the thrust collar, the thrust collar then pushes the buffer piston to move backwards, and the hydraulic fluid in the buffer cavity is gradually discharged under the extrusion of the buffer piston; the arrangement of the buffer piston can limit the rebound displacement of the drill rod and relieve the impact, and the hydraulic fluid is utilized to absorb the impact energy to realize the buffer effect, thereby protecting the drill rod tail from being damaged.

Drawings

Fig. 1 is a schematic cross-sectional view (first perspective) of a cushioning mechanism for a hydraulic rock drill of the present invention;

fig. 2 is a schematic cross-sectional view (second perspective) of a cushioning mechanism for a hydraulic rock drill according to the present invention;

fig. 3 is a schematic sectional view (third view) of a buffer mechanism for a hydraulic rock drill according to the present invention.

The reference numerals in the figures denote: 1. a drill rod; 2. a thrust ring; 3. a cushion piston; 4. a buffer chamber; 51. a high-pressure oil port; 521. a first high pressure channel; 522. a second high pressure channel; 53. a damping hole; 541. a first buffer channel; 542. a second buffer channel; 6. the piston is impacted.

Detailed Description

The invention will be described in further detail below with reference to the drawings and specific examples.

Referring to fig. 1 to 3, a first embodiment of a damping mechanism for a hydraulic rock drill according to the present invention includes a housing having a damping cylinder, in which a drill rod 1, a thrust collar 2, and a damping piston 3 are sequentially installed from front to back; the thrust ring 2 is sleeved at the rear end of the drill rod 1 and used for limiting the backward axial displacement of the drill rod 1; the buffer piston 3 is arranged at the front end of the buffer cylinder which is provided with an annular groove in a reciprocating motion way, and the buffer piston 3 closes the annular groove to form a buffer cavity 4; hydraulic fluid capable of pushing the buffer piston 3 to move forwards to abut against the thrust ring 2 is filled in the buffer cavity 4; the drill rod 1 stops moving backwards by impacting the thrust ring 2 when rebounding, and then the thrust ring 2 impacts the buffer piston 3 backwards; the damping piston 3 is moved backward by pushing the hydraulic fluid out of the damping chamber 4 when it is subjected to a collision, to damp the shock. When the bit impacts the external structure and rebounds, the drill rod 1 which axially moves backwards impacts the thrust ring 2, the thrust ring 2 pushes the buffer piston 3 to move backwards, and the hydraulic fluid in the buffer cavity 4 is gradually discharged under the extrusion of the buffer piston 3; the arrangement of the buffer piston 3 can limit the rebound displacement of the drill rod 1 and relieve the impact, and the hydraulic fluid is utilized to absorb the impact energy to realize the buffer effect, thereby protecting the drill rod shank from damage.

Preferably, the casing is formed with the intercommunication the oil feed passageway of cushion chamber 4, the oil feed passageway be used for to inject in the cushion chamber 4 hydraulic fluid. Because in the process of realizing the buffering function, the hydraulic fluid in the buffering cavity 4 is extruded out, in order to ensure effective buffering in the next impact, the hydraulic fluid must be timely filled in the buffering cavity 4, and the oil can be more conveniently filled by the arrangement of the oil inlet channel.

Preferably, the housing is formed with an oil outlet passage communicating with the cushion chamber 4, the oil outlet passage being for discharging the hydraulic fluid in the cushion chamber 4 when the cushion piston 3 is subjected to a collision. Since the hydraulic fluid in the buffer chamber 4 will be squeezed out during the process of implementing the buffer function, the oil outlet passage is provided in order to collect and reuse the squeezed hydraulic fluid; the oil outlet channel is used for communicating the buffer cavity 4 with the low-pressure energy accumulator and is communicated with the outside through the low-pressure energy accumulator; the extruded hydraulic fluid is uniformly stored and conveyed to the low-pressure accumulator through the oil outlet channel to be secondarily utilized and then discharged.

Preferably, the oil inlet passage includes a high-pressure oil port 51 for injecting high-pressure hydraulic fluid, a high-pressure passage for accommodating the high-pressure hydraulic fluid, a damping hole 53 for depressurizing the high-pressure hydraulic fluid to form sub-high-pressure hydraulic fluid, and a buffer passage for accommodating the sub-high-pressure hydraulic fluid and injecting the sub-high-pressure hydraulic fluid into the buffer chamber 4, which are sequentially communicated. Since the pressure of the hydraulic fluid entering the buffer chamber 4 determines the buffering efficiency, in order to better adjust the pressure of the hydraulic fluid in the buffer chamber 4 to a suitable range for achieving an optimal buffering effect, the damping hole 53 is provided between the high pressure passage and the buffer passage, and the high pressure hydraulic fluid is converted into the sub-high pressure hydraulic fluid through the damping hole 53.

Preferably, the high pressure passage includes a first high pressure passage 521 and a second high pressure passage 522 which are sequentially communicated in the flow direction of the high pressure hydraulic fluid; one end of the first high-pressure passage 521, which is far away from the second high-pressure passage 522, is communicated with the high-pressure oil port 51; the damping hole 53 is formed at an end of the second high pressure passage 522 distant from the first high pressure passage 521. The buffer passage includes a first buffer passage 541 and a second buffer passage 542 that are sequentially communicated in the flow direction of the sub-high pressure hydraulic fluid; one end of the first buffer channel 541 far from the second buffer channel 542 is connected with the damping hole 53; one end of the second buffer passage 542, which is far from the first buffer passage 541, communicates with the buffer chamber 4. Since the layout path between the high-pressure channel and the buffer channel is not straight, in order to optimize the structural layout of the hydraulic rock drill, the high-pressure channel and the buffer channel are respectively divided into two sections and arranged in the shell.

According to the second embodiment of the buffer mechanism for the hydraulic rock drill, provided by the invention, the buffer cylinder is provided with the impact piston 6; the drill rod 1, the thrust collar 2 and the buffer piston 3 and the percussion piston 6 are arranged coaxially. Because the drill rod 1, the thrust ring 2, the buffer piston 3 and the impact piston 6 are impacted quickly to perform piston movement in a working state, the radial component force generated by eccentric impact is prevented from damaging the shell and is coaxially arranged in order to improve the stability of the equipment. In the rebound state of the drill rod 1, the rear end of the drill rod 1 passes through the thrust ring 2 and then stays in the buffer piston 3, and when impact is started, the front end of the impact piston 6 can be inserted into the buffer piston 3 and directly impacts the tail end of the drill rod 1 to provide power for the drill rod 1.

According to the third embodiment of the buffer mechanism for the hydraulic rock drill, provided by the invention, the groove wall at the front end of the annular groove is shallower than the groove wall at the rear end; the buffer piston 3 is used for sealing the outer wall of the annular groove to form a step so as to be attached to the annular groove; when the hydraulic fluid is injected into the buffer chamber 4, the hydraulic fluid pushes the step to advance; when the step is moved backwards, the hydraulic fluid is squeezed out of the buffer chamber 4. In order to realize the automatic reset function of the buffer piston 3, the annular groove with the front end groove wall shallower than the rear end groove wall is arranged, the outer wall of the annular groove for sealing the buffer piston 3 is arranged to be in a step shape attached to the outer wall, when the hydraulic fluid is injected into the buffer cavity 4, the step is pushed by the hydraulic fluid to move forwards, so that the buffer piston 3 moves forwards to extrude the thrust collar 2, and the reset is realized. When a collision occurs, the buffer piston 3 moves backwards, and correspondingly, the step moves backwards to extrude the hydraulic fluid in the buffer cavity 4 and discharge the hydraulic fluid. Then, the hydraulic fluid is again injected into the buffer chamber 4, and the buffer piston 3 is pushed to move forward and return, thereby reciprocating.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.