A down-the-hole hammer

Abstract

The utility model provides a kind of down-the-hole hammer, comprising: outer sleeve tube;Piston, coaxial sleeve is installed in the outer sleeve tube, the piston separates the outer sleeve tube into first gas chamber and second gas chamber;Gas distribution passage is arranged between the piston and the outer sleeve tube, the gas distribution passage is alternatively communicated with the first gas chamber and the second gas chamber, so that the first gas chamber and the second gas chamber exist between pressure difference, to push the piston moves along the axis direction of the outer sleeve tube;The gas distribution passage has spiral section, to generate spiral airflow, so that the piston rotates.Compared with prior art, the down-the-hole hammer provided by the utility model can avoid local wear of the piston, prolong the service life of the piston.

Description

Technical Field

[0001] This utility model relates to the field of mining machinery technology, and in particular to a down-the-hole impactor. Background Technology

[0002] Down-the-hole hammers are mainly used in mining rock drilling, hydrological well drilling and other operations. They work by using high-pressure compressed air supplied by an air compressor to enter the front and rear chambers of the hammer, causing the piston inside the hammer to reciprocate at high speed. The high-speed reciprocating piston strikes the drill bit, and finally the alloy teeth on the drill bit achieve rock breaking and drilling. The rock debris generated during the operation is blown out of the bottom of the hole by the high-pressure gas discharged from the hammer, and finally the hole is formed.

[0003] Current down-the-hole impactors rely on the high-frequency reciprocating motion of the piston to impact the drill bit. Under the continuous high-frequency impact, the outer wall of the piston and the outer cylinder often suffer from scratches or wear. Especially when the manufacturing precision of the piston or outer cylinder is poor, local wear of the piston often occurs, affecting the performance of the down-the-hole impactor. In severe cases, it may cause the piston to break or fail prematurely.

[0004] Therefore, there is an urgent need for a down-the-hole impactor that can prevent localized wear on the piston and extend its service life. Utility Model Content

[0005] In view of the technical problems in the prior art, this utility model provides a down-the-hole impactor that can avoid local wear of the piston and extend the service life of the piston.

[0006] A down-the-hole impactor, comprising: Outer tube; A piston is coaxially fitted inside the outer tube, and the piston divides the outer tube into a first air chamber and a second air chamber. An air distribution channel is disposed between the piston and the outer sleeve. The air distribution channel alternately communicates with the first air chamber and the second air chamber, so that there is a pressure difference between the first air chamber and the second air chamber, thereby pushing the piston to move along the axial direction of the outer sleeve. The gas distribution channel has a spiral section to generate a spiral airflow so that the piston rotates.

[0007] Preferably, the helical segment includes a helical groove that surrounds the piston along its axial direction, and a plurality of the helical grooves are arranged circumferentially around the piston.

[0008] Preferably, the spiral groove is provided on the outer surface of the piston.

[0009] Preferably, the spiral groove is disposed on the inner wall of the outer sleeve.

[0010] Preferably, the first helical groove is disposed on the outer surface of the piston, and the second helical groove is disposed on the inner wall of the outer sleeve.

[0011] Preferably, the gas distribution channel further includes: A plurality of air grooves are provided at the rear end of the piston, and are spaced apart around the outer surface of the piston. The air grooves are used to communicate with the spiral groove.

[0012] Preferably, the air groove has a spiral structure.

[0013] Preferably, it further includes: A connector assembly is fixedly connected to the rear end of the outer sleeve. A high-pressure air passage is provided inside the connector assembly, and the high-pressure air passage is used to communicate with the air distribution channel. The inner cylinder is fixedly fitted inside the outer sleeve, and the piston is movably fitted inside the inner cylinder; The drill bit assembly is fixedly connected to the front end of the outer sleeve. The drill bit assembly is provided with an exhaust channel, which is used to alternately communicate with the first air chamber and the second air chamber. The first air chamber is formed between the joint assembly, the inner cylinder, the piston, and the outer sleeve, and the second air chamber is formed between the drill bit assembly, the piston, and the outer sleeve.

[0014] Preferably, the gas distribution channel further includes: The first air passage is located between the inner cylinder and the outer sleeve; A first vent hole is provided at the front end of the inner cylinder. The first vent hole communicates with the first air passage. The piston moves along the axial direction of the inner cylinder so that the first air passage and the air groove are connected through the first vent hole. A plurality of first vent holes are arranged circumferentially around the inner cylinder.

[0015] Preferably, the gas distribution channel further includes: A second vent is provided at the rear end of the inner cylinder. The second vent is used to connect the first air passage and the high-pressure air passage. A plurality of second vents are arranged circumferentially around the inner cylinder.

[0016] Compared with existing technologies, the down-the-hole impactor provided by this utility model, firstly, features an outer sleeve, a piston, and an air distribution channel. The piston is coaxially mounted inside the outer sleeve, dividing the sleeve into a first air chamber and a second air chamber. The air distribution channel is located between the outer sleeve and the piston, alternately communicating with the first and second air chambers to create a pressure difference that drives the piston to move along the axial direction of the outer sleeve. To prevent localized wear on the piston, the air distribution channel has a spiral section where high-pressure airflow generates a spiral airflow. This spiral airflow drives the piston to rotate. During operation, the piston rotates while moving axially, preventing localized wear on its outer surface. Therefore, compared with existing technologies, the down-the-hole impactor provided by this utility model can avoid localized wear on the piston and extend its service life. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of a down-the-hole impactor provided in an embodiment of this utility model; Figure 2 A schematic diagram of an outer sleeve provided for an embodiment of this utility model (a spiral groove is provided on the inner wall of the outer sleeve); Figure 3 This is a schematic diagram of a first structure of a piston provided in an embodiment of the present utility model; Figure 4 This is a schematic diagram of a second structure of the piston provided in an embodiment of the present invention.

[0019] Reference numerals: 1. Outer tube; 2. Piston; 3. First air chamber; 4. Second air chamber; 5. Air distribution passage; 51. Spiral groove; 52. Air groove; 53. First air passage; 54. First vent hole; 55. Second vent hole; 6. Connector assembly; 61. High-pressure air passage; 7. Inner cylinder; 8. Drill bit assembly; 81. Exhaust passage. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to the other component.

[0022] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0023] like Figures 1 to 4 As shown, this utility model provides a down-the-hole impactor, including an outer tube 1; a piston 2, coaxially fitted inside the outer tube 1, to divide the outer tube 1 into a first air chamber and a second air chamber 4; an air distribution channel 5, disposed between the piston 2 and the outer tube 1, the air distribution channel 5 alternately communicating with the first air chamber 3 and the second air chamber 4, so that there is an air pressure difference between the first air chamber 3 and the second air chamber 4, to push the piston 2 to move along the axial direction of the outer tube 1; the air distribution channel 5 has a spiral section to generate a spiral airflow, so that the piston 2 rotates.

[0024] Current down-the-hole impactors rely on the high-frequency reciprocating motion of the piston to impact the drill bit. Under the continuous high-frequency impact, the outer wall of the piston and the outer cylinder often suffer from scratches or wear. Especially when the manufacturing precision of the piston or outer cylinder is poor, local wear of the piston often occurs, affecting the performance of the down-the-hole impactor. In severe cases, it may cause the piston to break or fail prematurely.

[0025] Compared with existing technologies, the down-the-hole impactor provided by this utility model, firstly, features an outer sleeve 1, a piston 2, and an air distribution channel 5. The piston 2 is coaxially disposed within the outer sleeve 1, dividing the outer sleeve 1 into a first air chamber 3 and a second air chamber 4. The air distribution channel 5 is located between the outer sleeve 1 and the piston 2, alternately communicating with the first air chamber 3 and the second air chamber 4 to create a pressure difference between them. This pressure difference drives the piston 2 to move along the axial direction of the outer sleeve 1. To prevent localized wear on the piston 2, the air distribution channel 5 has a spiral section. High-pressure airflow flows within the spiral end to generate a spiral airflow, which drives the piston 2 to rotate. During operation, the piston 2 rotates while moving axially, preventing localized wear on its outer surface. Therefore, compared with existing technologies, the down-the-hole impactor provided by this utility model can avoid localized wear on the piston 2 and extend its service life.

[0026] In existing technologies, piston movement is a vertical impact, while the down-the-hole piston provided by this technology relies on rotational impact. Rotational impact combines rotational motion with vertical impact force, offering several advantages over simple vertical impact. Specifically: 1. Higher energy efficiency: Rotary impact combines rotational motion with vertical impact, resulting in less energy loss and more efficient energy transfer; vertical impact relies solely on vertical impact force, leading to lower efficiency.

[0027] 2. Wider range of applications: Suitable for complex working conditions, such as drilling in hard rock. Rotary impact drilling technology can break hard rock layers through the synergistic effect of high-frequency impact and rotary shearing, with an efficiency 45% higher than traditional vertical impact drilling rigs; vertical impact is mainly used for testing or breaking in a single direction, and can cope with multi-angle or complex bottom layers.

[0028] 3. More thorough crushing effect: In rotary impact drilling, high-frequency shock waves are superimposed with rotational shear force, causing volumetric crushing of the rock. The efficiency is far greater than that of vertical impact, which relies only on vertical force and has a limited crushing range. For example, traditional impact drilling rigs need to repeatedly backfill and flush in hard rock, which is inefficient and easily wears down the drill bit.

[0029] 4. Better safety and ease of operation: Rotary impact reduces personnel risk, and the rotary impact drill is equipped with a counter-impact function to avoid equipment damage caused by stuck drill; Vertical impact may cause local overload due to force in one direction during testing or operation. For example, the vertical impact table needs to be strictly calibrated for platform flatness to avoid errors.

[0030] 5. Better economic efficiency and sustainability: Rotary impact drills shorten hole cleaning time by 15 days compared to vertical impact drills, saving labor, electricity and material costs; while vertical impact drills require frequent drill bit replacements.

[0031] In summary, rotational impact is more effective than vertical impact, as summarized in Table 1 below.

[0032] Table 1 Comparison of Rotational Impact and Vertical Impact

[0033] Furthermore, as one embodiment, the helical segment in this utility model includes a helical groove 51, which surrounds the piston 2 along its axial direction. Multiple helical grooves 51 are spaced apart circumferentially around the piston 2. When the high-pressure air passage 61 flows within the helical groove 51, it drives the piston 2 to rotate, thereby preventing localized wear between the piston 2 and the outer cylinder, which would affect the service life of the piston 2.

[0034] More specifically, the spiral groove 51 can be configured in various ways. As one of the first implementation methods, such as... Figure 4 As shown, in this embodiment of the invention, the spiral groove 51 is disposed on the outer surface of the piston 2. The spiral groove 51, disposed on the outer circumferential surface of the piston 2, facilitates machining.

[0035] However, machining the spiral groove 51 on the outer surface of the piston 2 may damage the strength of the piston 2. As a second implementation, such as Figure 2 As shown in the figure, the spiral groove 51 in this embodiment of the present invention is provided on the inner surface of the outer sleeve 1. The structural schematic diagram of the piston is as follows. Figure 3 As shown.

[0036] In addition, existing technologies often use straight grooves on the outer surface of the piston to drive the piston to move axially. However, the outer surface of the piston often wears against the inner surface of the outer cylinder. By setting spiral grooves on the inner surface of the outer sleeve, the piston rotates while moving axially, which does not cause excessive wear on the outer surface of the piston and extends the service life of the piston.

[0037] In a third embodiment of this invention, the first helical groove is disposed on the outer surface of the piston 2, and the second helical groove is disposed on the inner surface of the outer sleeve 1. Figure 2 outer cylinder and Figure 4 The piston combination is used.

[0038] All three methods involve forming a spiral section between piston 2 and outer sleeve 1. This allows the high-pressure gas to rotate within the spiral section, preventing severe wear on piston 2 during axial movement. When piston 2 rotates while moving axially, the wear between piston 2 and the outer cylinder becomes more even.

[0039] Furthermore, as one embodiment, the spiral groove 51 in this utility model embodiment is disposed at the front end of the piston 2. Here, the front end refers to the end of the down-the-hole impactor near the drill bit assembly in the use state as the front end, and the end near the connector assembly as the rear end.

[0040] In the above structure, as one embodiment, the gas distribution channel 5 in this utility model embodiment also includes a gas groove 52. The gas groove 52 is disposed at the rear end of the piston 2. Multiple gas grooves 52 are arranged at intervals around the outer surface of the piston 2. The gas grooves 52 are used to communicate with the spiral groove 51.

[0041] In the above structure, the air groove 52 can be a straight groove, an inclined groove, or a spiral groove 51. As a more preferred embodiment, the air groove 52 in this utility model embodiment is specifically a spiral structure, such as... Figure 4 As shown.

[0042] In the above structure, as one embodiment, the down-the-hole impactor of this utility model further includes a connector assembly 6, an inner cylinder 7, and a drill assembly 8. The connector assembly 6 is fixedly connected to the rear end of the outer sleeve 1. A high-pressure air passage 61 is provided on the connector assembly 6, which communicates with the air distribution channel 5. The inner cylinder 7 is fixedly fitted inside the outer sleeve 1, and the piston 2 is movably fitted inside the inner cylinder 7. The drill assembly 8 is fixedly connected to the front end of the outer sleeve 1. An exhaust passage 81 is provided inside the drill assembly 8, which communicates with the air distribution channel 5. A first air chamber 3 is formed between the connector assembly 6, the inner cylinder 7, the piston 2, and the outer sleeve 1. A second air chamber 4 is formed between the drill assembly 8, the piston 2, and the outer sleeve 1. The air distribution channel 5 communicates with the high-pressure air passage 61 and alternately communicates with the first air chamber 3 and the second air chamber 4 as the piston 2 moves axially. Due to the pressure difference between the two ends of the piston 2, the piston 2 is pushed to move axially. Because a helical section is provided inside the air distribution channel 5, the piston 2 rotates while moving axially. It should be noted that the improvement in this embodiment is mainly achieved by setting a spiral segment. The structures of the connector assembly 6 and the drill bit assembly 8 can both adopt existing structures. The specific structures of the connector assembly 6 and the drill bit assembly 8 will not be further described here.

[0043] Furthermore, as one embodiment, the air distribution channel 5 in this utility model embodiment also includes a first air passage 53 and a first vent hole 54. The first air passage 53 is disposed between the inner cylinder 7 and the outer sleeve 1, and the first vent hole 54 is disposed at the front end of the inner cylinder 7. The first vent hole 54 communicates with the first air passage 53. The piston 2 moves along the axial direction of the inner cylinder 7 so that the first air passage 53 and the air groove 52 are connected through the first vent hole 54. A plurality of first vent holes 54 are arranged circumferentially around the inner cylinder 7.

[0044] Furthermore, as one embodiment, the air distribution channel 5 in this utility model embodiment also includes a second vent hole 55. The second vent hole 55 is disposed at the rear end of the inner cylinder 7. The second vent hole 55 is used to connect the first air passage 53 and the high-pressure air passage 61. A plurality of second vent holes 55 are arranged circumferentially around the inner cylinder 7.

[0045] The above description is merely an embodiment of this utility model. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of this utility model, but these improvements all fall within the protection scope of this utility model.

Claims

1. A down-the-hole impactor, characterized in that, include: Outer tube (1); The piston (2) is coaxially fitted inside the outer tube (1), and the piston (2) divides the outer tube (1) into a first air chamber (3) and a second air chamber (4). An air distribution channel (5) is provided between the piston (2) and the outer sleeve (1). The air distribution channel (5) alternately communicates with the first air chamber (3) and the second air chamber (4), so that there is a pressure difference between the first air chamber (3) and the second air chamber (4), so as to push the piston (2) to move along the axial direction of the outer sleeve (1). The gas distribution channel has a spiral section to generate a spiral airflow so that the piston (2) rotates.

2. The down-the-hole impactor according to claim 1, characterized in that, The helical segment includes a helical groove (51) that surrounds the piston (2) along its axial direction, and a plurality of the helical grooves (51) are arranged circumferentially around the piston (2).

3. The down-the-hole impactor according to claim 2, characterized in that, The spiral groove (51) is provided on the outer surface of the piston (2).

4. The down-the-hole impactor according to claim 2, characterized in that, The spiral groove (51) is provided on the inner wall of the outer sleeve (1).

5. The down-the-hole impactor according to claim 2, characterized in that, The first spiral groove is provided on the outer surface of the piston (2), and the second spiral groove is provided on the inner wall of the outer sleeve (1).

6. The down-the-hole impactor according to any one of claims 1 to 5, characterized in that, The gas distribution channel (5) also includes: A gas groove (52) is provided at the rear end of the piston (2). A plurality of gas grooves (52) are arranged at intervals around the outer surface of the piston (2). The gas grooves (52) are used to communicate with the spiral groove (51).

7. The down-the-hole impactor according to claim 6, characterized in that, The air groove (52) is specifically a spiral structure.

8. The down-the-hole impactor according to claim 6, characterized in that, Also includes: The connector assembly (6) is fixedly connected to the rear end of the outer sleeve (1). The connector assembly (6) is provided with a high-pressure air passage (61), which is used to communicate with the air distribution channel (5). The inner cylinder (7) is fixedly fitted inside the outer sleeve (1), and the piston (2) is movably fitted inside the inner cylinder (7); The drill bit assembly (8) is fixedly connected to the front end of the outer sleeve (1). The drill bit assembly (8) is provided with an exhaust channel (81), which is used to alternately communicate with the first air chamber and the second air chamber. The first air chamber (3) is formed between the connector assembly (6), the inner cylinder (7), the piston (2) and the outer sleeve (1), and the second air chamber (4) is formed between the drill bit assembly (8), the piston (2) and the outer sleeve (1).

9. The down-the-hole impactor according to claim 8, characterized in that, The gas distribution channel (5) also includes: The first air passage (53) is disposed between the inner cylinder (7) and the outer sleeve (1); The first vent hole (54) is provided at the front end of the inner cylinder (7). The first vent hole (54) is connected to the first air passage (53). The piston (2) moves along the axial direction of the inner cylinder (7) so that the first air passage (53) and the air groove (52) are connected through the first vent hole (54). A plurality of first vent holes (54) are arranged circumferentially around the inner cylinder (7).

10. The down-the-hole impactor according to claim 9, characterized in that, The gas distribution channel (5) also includes: The second vent (55) is provided at the rear end of the inner cylinder (7). The second vent (55) is used to connect the first air passage (53) and the high-pressure air passage (61). A plurality of second vents (55) are arranged circumferentially around the inner cylinder (7).

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