Impact device, hydraulic power head and rock drill

Abstract

The invention discloses an impact device, a hydraulic power head and a rock drill. The impact device comprises an impact shell and an impact piston, and a reversing device and a frequency modulation device are arranged on the impact shell; the impact piston is provided with a first matching face facing the front end and a second matching face facing the tail end, the acting area of the second matching face is larger than that of the first matching face, and a front cavity used for being matched with the first matching face and a rear cavity used for being matched with the second matching face are formed in the inner wall of the impact shell. The front cavity is connected with a first high-pressure oil source through a first oil way, the rear cavity is connected with a reversing device through a second oil way, and the reversing device is provided with a high-pressure oil port connected with the first high-pressure oil source and a low-pressure oil port connected with a first low-pressure oil source. The reversing device is used for controlling the rear cavity to be connected with a first low-pressure oil source when the impact piston moves to a first preset range and enabling the rear cavity to be connected with a first high-pressure oil source when the impact piston moves to a second preset range. The frequency modulation device is used for adjusting the size of the second preset range.

Description

Technical Field

[0001] The present invention relates to the technical field of rock drilling and impact drilling, and in particular, to an impact device. In addition, the present invention also relates to a hydraulic power head and a rock drill including the impact device. Background Art

[0002] In tunnel construction, pipe shed construction, geological forecasting, geological coring, anchor bolts, grouting reinforcement, geological improvement and other construction are required. In these constructions, hydraulic impact power heads are widely used. When drilling forward, the impact device of the hydraulic power head is installed at the rear of the gear box. The impact piston performs high-frequency impact on the drill tail, and the impact energy is transmitted to the drill bit through the drill rod, acting on the rock surface and impacting and destroying it. Under the action of the impact force, the drilling speed can be greatly accelerated and the construction efficiency can be improved.

[0003] There are many structural forms of hydraulic impact devices. Among them, the sleeve valve impact device has a large number of moving parts, and the reversing valve is generally installed at the rear of the piston, which leads to a large size of the overall impact device, high oil consumption and leakage. At the same time, the sleeve valve structure has a complex oil circuit, and the structural design of the impact frequency adjustment cannot be performed. The impact device has only one frequency and poor geological adaptability. For example, the impact device disclosed in the invention patent with publication number: CN117823033A includes a cylinder, an impact piston, a distribution valve, a push rod, an oil distribution cover and an end cover. The distribution valve, the oil distribution cover and the push rod are arranged at the rear of the impact piston. When the impact piston moves under the action of hydraulic oil, the change of the oil circuit changes the force state and movement state of the distribution valve, the oil distribution cover and the push rod, thereby changing the oil circuit pressure of each step surface on the impact piston, and realizing the reciprocating motion of the impact piston. This impact device is a sleeve valve structure, and the moving parts are all installed at the rear of the piston, which leads to a large size of the whole machine and increased oil consumption. At the same time, this type of device has many moving parts, the movement states of each part are complex, and the failure rate is relatively high. At the same time, this impact device cannot be frequency-modulated, and the impact frequency and impact power cannot be adjusted.

[0004] The reversing valve of the core valve type impact device is not coaxial with the impact piston, which can effectively reduce the size of the impact device. However, the valve core of the reversing valve uses a spring for reversing. Under high-frequency impact, the life of the spring will be reduced due to fatigue stress, and the long-term continuous operation of the impact device cannot be guaranteed. For example, the multi-frequency hydraulic rotary impact drill disclosed in the invention patent with publication number: CN107044258A includes an impact mechanism, a rotation mechanism, and a back-hitting mechanism connected in sequence, and a reversing mechanism and a reversing valve are installed on the outside of the impact mechanism. Its reversing valve is installed on the side of the impact piston, and adopts a core valve structure. The structural size of its impact device can be controlled to be smaller. However, its reversing valve uses a spring for reversing. Under the high-frequency impact, the fatigue strength requirements of the spring are higher, and the life of the spring is greatly reduced, affecting the performance of the impact device.

[0005] On the other hand, the impact frequency adjustment structure of the current hydraulic impact device usually relies on manual mechanical adjustment. In the tunnel face, manual adjustment poses a great safety hazard. Summary of the invention

[0006] The present invention provides an impact device, a hydraulic power head and a rock drill to solve the technical problems that the existing impact device has a large number of parts, resulting in a complex motion state, a high failure rate, and a short service life of a reversing device based on a spring.

[0007] According to one aspect of the present invention, there is provided an impact device, comprising an impact shell and an impact piston penetrating through an inner cavity of the impact shell, wherein a reversing device and a frequency modulation device are arranged on the impact shell; the impact piston has a first mating surface arranged toward the front end and a second mating surface arranged toward the rear end, the effective area of ​​the second mating surface is larger than the effective area of ​​the first mating surface, the inner wall of the impact shell is respectively formed with a front cavity for mating with the first mating surface and a rear cavity for mating with the second mating surface, the front cavity is connected to a first high-pressure oil source via a first oil circuit, and the rear cavity is connected to the reversing device via a second oil circuit, the reversing device has a high-pressure oil port connected to the first high-pressure oil source and a low-pressure oil port connected to the first low-pressure oil source, the reversing device is used to control the rear cavity to connect to the first low-pressure oil source when the impact piston moves to a first preset range, and is used to connect the rear cavity to the first high-pressure oil source when the impact piston moves to a second preset range; the frequency modulation device is used to adjust the size of the second preset range.

[0008] As a further improvement of the above technical solution, a first control chamber is provided on the inner wall of the impact housing, the first control chamber is connected to the reversing device via a third oil circuit, and the first control chamber is connected to the frequency modulation device via a fourth oil circuit; the impact housing is axially distributed with a plurality of signal oil circuits connected to the frequency modulation device, and the frequency modulation device is used to respectively control the on and off of each of the signal oil circuits and thereby control the size of the second preset range.

[0009] As a further improvement of the above technical solution, a frequency modulation valve core is inserted into the frequency modulation device, the first end of the frequency modulation device is connected to a second high-pressure oil source, and the first end of the frequency modulation device is in the same direction as the front end of the impact device; an elastic reset member is arranged between the frequency modulation valve core and the inner wall of the second end of the frequency modulation device, and the frequency modulation valve core is used to be driven by the second high-pressure oil source to move toward the second end and thereby sequentially block the signal oil circuit.

[0010] As a further improvement of the above technical solution, the two ends of the reversing device are respectively connected to a first high-pressure oil source, and a distribution sleeve and a reversing valve core are arranged in the reversing device, and the effective area of ​​the first end of the reversing valve core is larger than the effective area of ​​the second end; the reversing device is provided with a distribution chamber, a first chamber, and a second chamber in sequence along the axial direction, and the distribution chamber is connected to the first control chamber via a third oil circuit, the first chamber is connected to a first low-pressure oil source, and the second chamber is connected to the rear chamber via a second oil circuit; the reversing valve core is used to connect the first chamber with the second chamber when it moves to a preset position, or to connect the second chamber with the first high-pressure oil source connected to the second end of the reversing device when it moves to a preset position.

[0011] As a further improvement of the above technical solution, a second control chamber is provided on the inner wall of the impact housing, and the second control chamber is connected with the first chamber via a fifth oil circuit; a drainage groove is provided on the outer wall of the impact piston, which is used to connect the third oil circuit and the fifth oil circuit when the impact piston moves to a preset range to a third preset range.

[0012] As a further improvement of the above technical solution, the inner wall of the impact housing is provided with a plurality of lubrication cavities and a lubrication oil circuit connecting the lubrication cavities and the fifth oil circuit, or the inner wall of the impact housing is provided with a plurality of lubrication cavities and a lubrication oil port is provided corresponding to each of the lubrication cavities, and the reversing device is provided with a lubrication oil circuit connected to the first chamber corresponding to each of the lubrication oil ports.

[0013] As a further improvement of the above technical solution, the second end of the frequency modulation device is connected to a second low-pressure oil source.

[0014] As a further improvement of the above technical solution, a stop cavity is provided on the inner wall of the impact shell, which is arranged between the front end of the impact shell and the front cavity, and is used to form a blind cavity when the impact piston moves toward the first end until the outer wall of the impact piston cooperates with the stop cavity, thereby braking the impact piston.

[0015] According to another aspect of the present invention, there is also provided a hydraulic power head, to which the above-mentioned impact device is applied, and the hydraulic power head comprises a reduction box and a front guide device.

[0016] According to another aspect of the present invention, a rock drill is provided, which comprises the above-mentioned impact device.

[0017] The present invention has the following beneficial effects:

[0018] The high-pressure oil reaches the front chamber through the first oil circuit, and the reversing device connects the first high-pressure oil source to the second oil circuit to the rear chamber. Because the effective area of ​​the first mating surface is smaller than the effective area of ​​the second mating surface, the impact piston moves to the front end and hits the drill tail under the action of the area difference, and enters the first preset range at this time. Under the action of the reversing device, the second oil circuit is connected to the first low-pressure oil source, and the rear chamber is connected to low-pressure oil. Under the action of the pressure difference between the front and rear chambers, the impact piston performs a return acceleration movement toward the rear chamber. During the return process, when the impact piston moves to the second preset range, the reversing device is activated to connect the second oil circuit to the first high-pressure oil source, and the rear chamber is connected to high-pressure oil. Because the effective area of ​​the first mating surface is smaller than the effective area of ​​the second mating surface, the impact piston performs a return deceleration movement, and completes a cycle of action after the deceleration is 0, and the impact piston continues to move to the front end and hits the drill tail. The structural principle of the impact device is simplified, and the moving parts are The number of parts is small, which greatly reduces the failure rate. The movement logic is concise and clear, the movement process of the impact piston is clear, and the accuracy of dynamic calculation is effectively improved, and the reliability of the whole machine is improved; the reversing device is connected to the impact piston through multiple oil circuits, and the reversing is realized based on hydraulic pressure as the movement process of the impact piston changes. The structure is simple and avoids the use of springs, avoiding high-frequency movement and causing spring fatigue failure and equipment failure; the second preset range is adjusted by the frequency modulation device, and then the position of the impact piston for return deceleration movement is changed, so as to adjust the impact piston stroke and then realize the adjustment of its impact frequency and impact power, which is easy and safe to operate; the reversing device and the frequency modulation device are integrated on the impact housing, with a compact structure and reduced space occupancy; through the preset oil circuit and oil port matching connection, disassembly and maintenance are convenient, and no pipeline connection is required, which improves disassembly and assembly efficiency and streamlines the structure.

[0019] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 It is a structural schematic diagram of a preferred embodiment of the present invention;

[0022] Figure 2 It is a schematic diagram of the internal structure of a preferred embodiment of the present invention;

[0023] Figure 3 It is a schematic diagram of the internal structure when the impact piston hits the shank of the preferred embodiment of the present invention;

[0024] Figure 4 It is a schematic diagram of the internal structure of the impact piston return process of the preferred embodiment of the present invention;

[0025] Figure 5 It is a schematic diagram of the internal structure of the impact piston decelerating to zero in a preferred embodiment of the present invention;

[0026] Figure 6 It is a structural schematic diagram of a hydraulic power head according to a preferred embodiment of the present invention.

[0027] Legend:

[0028] 1. Impact housing; 101. Reversing device; 102. Frequency modulation device; 103. Front chamber; 104. Rear chamber; 105. Stop chamber; 106. First oil circuit; 107. Second oil circuit; 108. Third oil circuit; 109. Fourth oil circuit; 110. Fifth oil circuit; 111. Sixth oil circuit; 112. First signal oil circuit; 113. Second signal oil circuit; 114. Third signal oil circuit; 115. Lubricating oil circuit; 2. Rear cover; 3. , impact piston; 31, threaded hole; 4, reversing valve core; 41, flow hole; 42, distribution chamber; 5, distribution sleeve; 6, first end cover; 7, second end cover; 8, frequency modulation valve core; 9, elastic reset member; 10, third end cover; 11, fourth end cover; 12, first step seal; 13, second step seal; 14, sealing ring; 15, first high-pressure oil source; 16, first low-pressure oil source; 17, second high-pressure oil source; 18, second low-pressure oil source. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0030] like Figures 1 to 5 As shown, the impact device of this embodiment includes an impact shell 1 and an impact piston 3 penetrating the inner cavity of the impact shell 1. The impact shell 1 is provided with a reversing device 101 and a frequency modulation device 102; the impact piston 3 has a first matching surface arranged toward the front end and a second matching surface arranged toward the rear end, the effective area of ​​the second matching surface is larger than the effective area of ​​the first matching surface, and the inner wall of the impact shell 1 is respectively formed with a front cavity 103 for matching with the first matching surface and a rear cavity 104 for matching with the second matching surface, and the front cavity 103 is formed through the second matching surface. An oil circuit 106 is connected to the first high-pressure oil source 15, and the rear chamber 104 is connected to the reversing device 101 through the second oil circuit 107. The reversing device 101 has a high-pressure oil port connected to the first high-pressure oil source 15 and a low-pressure oil port connected to the first low-pressure oil source 16. The reversing device 101 is used to control the rear chamber 104 to connect to the first low-pressure oil source 16 when the impact piston 3 moves to the first preset range, and is used to connect the rear chamber 104 to the first high-pressure oil source 15 when the impact piston 3 moves to the second preset range; the frequency modulation device 102 is used to adjust the size of the second preset range.

[0031] The working principle of the impact device is as follows: high-pressure oil reaches the front chamber 103 through the first oil circuit 106, and the reversing device 101 connects the first high-pressure oil source 15 to the second oil circuit 107 to the rear chamber 104. Because the effective area of ​​the first mating surface is smaller than the effective area of ​​the second mating surface, the impact piston 3 moves toward the front end and hits the drill tail under the action of the area difference, and enters the first preset range at this time. Under the action of the reversing device 101, the second oil circuit 107 is connected to the first low-pressure oil source 16, and the rear chamber 104 is connected to low-pressure oil. Under the action of the pressure difference between the front and rear chambers 104, the impact piston 3 performs a return acceleration movement toward the rear chamber 104. During the return process, when the impact piston 3 moves to the second preset range, the reversing device 101 is actuated to connect the second oil circuit 107 to the first high-pressure oil source 15, and the rear chamber 104 is connected to high-pressure oil. Because the effective area of ​​the first mating surface is smaller than the effective area of ​​the second mating surface, the impact piston 3 performs a return deceleration movement, and completes a cycle of action after the deceleration is 0, and the impact piston 3 continues to move toward the front end. Impact drill tail; The structural principle of the impact device is simple, the number of moving parts is small, the failure rate is greatly reduced, the movement logic is concise and clear, the movement process of the impact piston 3 is clear, the accuracy of dynamic calculation is effectively improved, and the reliability of the whole machine is improved; the reversing device 101 is connected to the impact piston 3 in multiple oil circuits, and the reversing is realized based on hydraulic pressure as the movement process of the impact piston 3 changes. The structure is simple and avoids the use of springs, avoiding high-frequency movement and causing spring fatigue failure and equipment failure; the second preset range is adjusted by the frequency modulation device 102, and then the position of the impact piston 3 for the return deceleration movement is changed, so as to adjust the stroke of the impact piston 3 and then realize the adjustment of its impact frequency and impact power, which is easy and safe to operate; the reversing device 101 and the frequency modulation device 102 are integrated on the impact shell 1, with a compact structure and reduced space occupancy; through the preset oil circuit and oil port matching connection, disassembly and maintenance are convenient and no pipeline connection is required, thereby improving disassembly and assembly efficiency and streamlining the structure.

[0032] In one embodiment, a first control chamber is provided on the inner wall of the impact housing 1, and the first control chamber is connected to the reversing device 101 via the third oil circuit 108, and the first control chamber is connected to the frequency modulation device 102 via the fourth oil circuit 109; the impact housing 1 is provided with a plurality of signal oil circuits connected to the frequency modulation device 102 along the axial direction, and the frequency modulation device 102 is used to control the on and off of each signal oil circuit respectively, and thus control the size of the second preset range. For example, in one embodiment, a first signal oil circuit 112, a second signal oil circuit 113 and a third signal oil circuit 114 are sequentially provided along the axial direction, and the first signal oil circuit 112 is located on the side close to the front end of the impact housing 1. When the three signal oil circuits are all opened, it is a high-frequency impact gear. When the impact piston 3 moves back to the first mating surface and reaches the first signal oil circuit 112, the front chamber 103 is connected to the first control chamber through the first signal oil circuit 112 and the fourth oil circuit 109, that is, high pressure The oil is connected to the reversing device 101 through the first signal oil circuit 112, the fourth oil circuit 109, the first control chamber and the third oil circuit 108, so that the reversing device 101 is actuated to change the state of the reversing device 101, so that the rear chamber 104 is switched from low-pressure oil to high-pressure oil, and a return deceleration movement is opened, and the movement cycle time of the impact piston 3 is short; similarly, when the first signal oil circuit 112 is blocked, the impact piston 3 returns to the position of the first matching surface reaching the second signal oil circuit 113 and starts the return deceleration movement, increasing the movement cycle time, and this is the medium-frequency impact gear; when the first signal oil circuit 112 and the second signal oil circuit 113 are blocked, the first matching surface reaches the position of the third signal oil circuit 114 and starts the return deceleration movement, and the movement cycle time increases, and this is the low-frequency impact gear; wherein, by designing the structure of the frequency modulation device 102, the last signal oil circuit close to the rear chamber 104 side cannot be blocked;

[0033] Specifically, a frequency modulation valve core 8 is inserted into the frequency modulation device 102, and the first end of the frequency modulation device 102 is connected to the second high-pressure oil source 17, and the first end of the frequency modulation device 102 is in the same direction as the front end of the impact device; an elastic reset member 9 is arranged between the frequency modulation valve core 8 and the inner wall of the second end of the frequency modulation device 102, and the frequency modulation valve core 8 is used to be driven by the second high-pressure oil source 17 to move toward the second end direction and then block the signal oil circuit in turn; a third end cover 10 is arranged at the first end of the frequency modulation device 102, and a fourth end cover 11 is arranged at the second end, so as to facilitate disassembly for maintenance Replacement; the frequency modulation device 102 overcomes the elastic force of the frequency modulation spring under the action of the hydraulic pressure of the second high-pressure oil source 17 to change the position of the frequency modulation valve core 8, thereby blocking the signal oil circuit, and as the frequency modulation device 102 moves toward the second end, the first signal oil circuit 112 and the second signal oil circuit 113 are blocked in turn; the axial position of the frequency modulation valve core 8 is changed by changing the input hydraulic pressure to change the number of signal oil circuit blockages, thereby realizing the switching of the impact frequency of the impact device, effectively avoiding manual mechanical adjustment, reducing safety hazards, and improving efficiency.

[0034] Among them, when the input liquid pressure of the frequency modulation device 102 is 0, all signal oil circuits are in the open state, which is the high-frequency impact gear; in some embodiments, a limiting structure can be set in the frequency modulation device 102, that is, the second end of the frequency modulation valve core 8 is designed to limit the position, and the frequency modulation valve core 8 moves to the second end until it abuts the limiting structure and only blocks the secondary signal oil circuit close to the rear cavity 104, ensuring that the last signal oil circuit cannot be blocked, that is, after the input liquid pressure reaches the maximum design value or higher, it is the low-frequency impact gear.

[0035] Furthermore, the second end of the frequency modulation device 102 is connected to the second low-pressure oil source 18, so that the hydraulic oil leaked in the frequency modulation valve returns to the oil tank.

[0036] In one embodiment, a first end cover 6 and a second end cover 7 are respectively provided at both ends of the reversing device 101, and both ends of the reversing device 101 are respectively connected to a first high-pressure oil source 15. A distribution sleeve 5 and a reversing valve core 4 are provided in the reversing device 101, and the first end of the reversing valve core 4 is in the same direction as the front end of the impact device, and the effective area of ​​the first end of the reversing valve core 4 is greater than the effective area of ​​the second end; a distribution chamber 42, a first chamber, and a second chamber are sequentially provided in the reversing device 101 along the axial direction, and the distribution chamber 42 is connected to the first control chamber via a third oil circuit 108, the first chamber is connected to the first low-pressure oil source 16, and the second chamber is connected to the rear chamber 104 via a second oil circuit 107; the reversing valve core 4 is used to connect the first chamber with the second chamber or move to a preset position when moving to the preset position. When the second chamber is set, the first high-pressure oil source 15 connected to the second end of the reversing device 101 is connected; specifically, the impact piston 3 impacts the drill tail, and the reversing valve core 4 is at the first end position at this time. Because the effective area of ​​the first end of the reversing valve core 4 is larger than the effective area of ​​the second end, the reversing valve starts to move toward the second end, the first chamber and the second chamber are connected, and the low-pressure oil enters the rear chamber 104 through the first chamber, the second chamber, and the second oil circuit 107, and the impact piston 3 starts to return and accelerate. The impact piston 3 returns and accelerates to the front chamber 103 and is connected to the first control chamber through the signal oil circuit, the fourth oil circuit 109, so that the high-pressure oil is guided to the first control chamber through the third oil circuit 108 to the distribution chamber 42, so that the pressure in the direction of the second end of the reversing valve core 4 is greater than the pressure in the direction of the first end. The reversing valve core 4 moves toward the first end, so that the high-pressure oil at the second end of the reversing valve core 4 is guided into the second chamber through the flow hole 41 at the tail end of the reversing valve core 4, and then the high-pressure oil is guided to the rear chamber 104 through the second oil circuit 107, so that the impact piston 3 starts the return deceleration movement, and starts the return acceleration movement after the deceleration is 0. After moving to the position of the signal oil circuit opened by the first matching surface, the front chamber 103 and the first control chamber are disconnected, and the distribution chamber 42 is switched to low-pressure oil. Under the action of the pressure difference, the reversing valve starts to move toward the second end again, that is, the reversing valve core 4 and the impact piston 3 both complete a cycle of action; the reversing device 101 has a simple structure, realizes reversing through hydraulic pressure, moves with the impact piston 3 and cooperates with the frequency modulation device 102 to realize hydraulic reversing control and reversing frequency control. The structure is simple and avoids the use of springs, thereby avoiding high-frequency movement causing spring fatigue failure and causing equipment failure; wherein, a second control chamber is arranged on the inner wall of the impact shell 1, and the second control chamber is connected with the first chamber via the fifth oil circuit 110, thereby connecting with the first low-pressure oil source 16; a drainage groove is arranged on the outer wall of the impact piston 3, which is used to connect the first control chamber and the second control chamber when the impact piston 3 moves to a preset range to a third preset range, so that the low-pressure oil is guided to the distribution chamber 42 through the first chamber, the fifth oil circuit 110, the drainage groove, and the third oil circuit 108, thereby changing the state of the reversing valve core 4; in the impact device, only the impact piston 3, the reversing valve core 4 and the frequency modulation valve core 8 are actuating elements, the structure is simple, highly integrated, the failure rate is low, the service life is long, and it is convenient for later maintenance.

[0037] Among them, in order to facilitate the maintenance and replacement of the impact piston 3, a rear cover 2 is set at the rear end of the impact shell 1, a sealing ring 14 is set at the connecting and matching part, and a threaded hole 31 is set at the rear end of the impact piston 3 for threaded connection with a tool. After disassembly, the impact piston 3 can be taken out by a tool.

[0038] In one embodiment, the inner wall of the impact shell 1 is provided with a plurality of lubrication chambers and a lubrication oil circuit 115 connecting the lubrication chambers and the fifth oil circuit 110, that is, the lubrication oil circuit 115 is all low-pressure oil supply and can be used as an oil return circuit. Specifically, low-pressure oil is introduced into a plurality of positions on the inner wall of the impact shell 1, such as the positions where the first step seal 12 and the second step seal 13 are provided at both ends to ensure the lubrication of the seals, and at the same time, the leaked hydraulic oil is returned to the oil tank through the lubrication oil circuit 115, so as to avoid the leakage oil from being pressurized and causing damage to the seal, thereby improving the reliability of the device.

[0039] In other embodiments, the inner wall of the impact housing 1 may be provided with a plurality of lubrication cavities and a lubrication oil port corresponding to each lubrication cavity, and the reversing device 101 may be provided with a lubrication oil path 115 connected to the first chamber corresponding to each lubrication oil port.

[0040] It should be understood that a flow hole 41 connected to the second end of the reversing valve core 4 is provided at an axial preset position on the reversing valve core 4, for connecting the second chamber with the first high-pressure oil source 15 when the reversing valve core 4 moves to the preset position.

[0041] In one embodiment, a stop chamber 105 is provided on the inner wall of the impact shell 1, which is arranged between the front end of the impact shell 1 and the front chamber 103, and is used to form a blind cavity when the impact piston 3 moves toward the first end until the outer wall of the impact piston 3 cooperates with the stop chamber 105, thereby braking the impact piston 3 to prevent the impact piston 3 from hitting the shell and avoiding damage to the equipment; the stop chamber 105 is connected to the first oil circuit 106 through the sixth oil circuit 111, and only a high-pressure oil interface needs to be retained outside the shell.

[0042] On the other hand, this embodiment also provides a hydraulic power head, referring to Figure 6 , the above-mentioned impact device is applied, and the hydraulic power head includes a reduction box and a front guide device.

[0043] On the other hand, this embodiment also provides a rock drill, which is equipped with the above-mentioned impact device.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An impact device, comprising an impact housing (1) and an impact piston (3) penetrating an inner cavity of the impact housing (1), characterized in that: The impact housing (1) is provided with a reversing device (101) and a frequency modulation device (102); the impact piston (3) has a first mating surface arranged toward the front end and a second mating surface arranged toward the rear end, the effective area of ​​the second mating surface is larger than the effective area of ​​the first mating surface, and the inner wall of the impact housing (1) is respectively formed with a front cavity (103) for mating with the first mating surface and a rear cavity (104) for mating with the second mating surface, the front cavity (103) is connected to a first high-pressure oil source (15) via a first oil path (106), and the rear cavity (104) is connected to a first high-pressure oil source (15) via a first oil path (106). The second oil circuit (107) is connected to the reversing device (101), and the reversing device (101) has a high-pressure oil port connected to a first high-pressure oil source (15) and a low-pressure oil port connected to a first low-pressure oil source (16). The reversing device (101) is used to control the rear chamber (104) to be connected to the first low-pressure oil source (16) when the impact piston (3) moves to a first preset range, and to control the rear chamber (104) to be connected to the first high-pressure oil source (15) when the impact piston (3) moves to a second preset range; the frequency modulation device (102) is used to adjust the size of the second preset range.

2. The impact device according to claim 1, characterized in that: The inner wall of the impact housing (1) is provided with a first control chamber, the first control chamber is connected to the reversing device (101) via a third oil circuit (108), and the first control chamber is connected to the frequency modulation device (102) via a fourth oil circuit (109); the impact housing (1) is provided with a plurality of signal oil circuits connected to the frequency modulation device (102) distributed along the axial direction, and the frequency modulation device (102) is used to respectively control the on and off of each of the signal oil circuits and thereby control the size of the second preset range.

3. The impact device according to claim 2, characterized in that: A frequency modulation valve core (8) is inserted into the frequency modulation device (102); the first end of the frequency modulation device (102) is connected to a second high-pressure oil source (17); the first end of the frequency modulation device (102) is in the same direction as the front end of the impact device; an elastic reset member (9) is provided between the frequency modulation valve core (8) and the inner wall of the second end of the frequency modulation device (102); the frequency modulation valve core (8) is used to be driven by the second high-pressure oil source (17) to move toward the second end and thereby sequentially block the signal oil path.

4. The impact device according to claim 2, characterized in that: The two ends of the reversing device (101) are respectively connected to a first high-pressure oil source (15); a distribution sleeve (5) and a reversing valve core (4) are provided in the reversing device (101); the effective area of ​​the first end of the reversing valve core (4) is larger than the effective area of ​​the second end; a distribution chamber (42), a first chamber, and a second chamber are sequentially provided in the reversing device (101) along the axial direction; the distribution chamber (42) is connected to the first control chamber via a third oil circuit (108); the first chamber is connected to a first low-pressure oil source (16); and the second chamber is connected to the rear chamber (104) via a second oil circuit (107); the reversing valve core (4) is used to connect the first chamber with the second chamber when it moves to a preset position, or to connect the second chamber with the first high-pressure oil source (15) connected to the second end of the reversing device (101) when it moves to a preset position.

5. The impact device according to claim 4, characterized in that: A second control chamber is provided on the inner wall of the impact housing (1), and the second control chamber is connected to the first chamber via a fifth oil passage (110); a drainage groove is provided on the outer wall of the impact piston (3), and is used to connect the third oil passage (108) and the fifth oil passage (110) when the impact piston (3) moves to a preset third preset range.

6. The impact device according to claim 5, characterized in that: The inner wall of the impact housing (1) is provided with a plurality of lubrication cavities and a lubrication oil path (115) connecting the lubrication cavities and the fifth oil path (110); or, the inner wall of the impact housing (1) is provided with a plurality of lubrication cavities and a lubrication oil port is provided corresponding to each of the lubrication cavities, and the reversing device (101) is provided with a lubrication oil path (115) connected to the first chamber corresponding to each of the lubrication oil ports.

7. The impact device according to claim 3, characterized in that: The second end of the frequency modulation device (102) is connected to a second low-pressure oil source (18).

8. The impact device according to claim 1, characterized in that: The inner wall of the impact housing (1) is provided with a stop chamber (105), which is arranged between the front end of the impact housing (1) and the front chamber (103), and is used to form a blind chamber when the impact piston (3) moves toward the first end until the outer wall of the impact piston (3) cooperates with the stop chamber (105), thereby braking the impact piston (3).

9. A hydraulic power head, characterized in that: The impact device according to any one of claims 1 to 8 is applied, and the hydraulic power head includes a reduction box and a front guide device.

10. A rock drill, characterized in that: The impact device according to any one of claims 1 to 8 is used.

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