Rock drill boom and rock drill

Abstract

The invention discloses a rock drill truck crank arm and a rock drill truck, and relates to the field of engineering machinery, which is used to realize the lightweight of the rock drill truck crank arm. The rock drill truck crank arm comprises a first connecting part, a second connecting part and a third connecting part. The first connecting part comprises a first mounting hole; the second connecting part comprises a second mounting hole; the central axis of the second mounting hole is parallel to the central axis of the first mounting hole; the third connecting part comprises a third mounting hole, and the central axis of the third mounting hole is perpendicular to the central axis of the first mounting hole. The rock drill truck crank arm provided by the technical scheme changes the relative relationship of the mounting holes of the first connecting part, the second connecting part and the third connecting part, so that the stress borne by the rock drill truck crank arm is greatly reduced after the rock drill truck crank arm is installed in place, and the weight and size of the rock drill truck crank arm can be reduced by more than 50%. Therefore, under the premise of considering the bearing capacity of the rock drill truck crank arm, the stress borne by the rock drill truck crank arm is reduced, and the lightweight and miniaturization of the rock drill truck crank arm are realized.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery, specifically to a rock drilling machine crank arm and a rock drilling machine. Background Technology

[0002] A rock drill is a type of rock drilling machinery used in tunnel and underground engineering projects, employing drill-and-blast construction. It is an important piece of equipment for tunnel and roadway excavation in underground mines, hydropower, railways, highways, and other fields. The rock drill's ability to assist in underground construction is largely due to the multiple degrees of freedom of the drill bit and the ability to adjust the drilling angle in real time according to the working environment.

[0003] As the main load-bearing structural component for achieving the aforementioned functions, the stability and reliability of the rock drill's boom directly determine the safety of the entire vehicle. In recent years, the drilling depth of rock drills has been continuously increasing, and the stress has been gradually increasing. Insufficient rigidity and strength of the boom structure have resulted in large deformation of the entire vehicle and easy cracking of the welds, affecting the use of the entire vehicle.

[0004] In related technologies, the crank arms used in rock drilling vehicles are welded, with the welds bearing the main load. The crank arms of rock drilling vehicles are subjected to large bending moments, requiring them to have high rigidity and strength, especially bending resistance. In existing technologies, the thickness of the crank arm plates is increased to improve the rigidity and strength of the crank arms.

[0005] The inventors discovered that the existing technology has at least the following problems: the existing crank arm structure is unreasonable, with many welds, and the crank arm's stiffness and strength are both weak. To improve its strength, the existing technology increases the thickness of the single plate, resulting in an increase in the weight of the crank arm structure, which is detrimental to its lightweight design. When using thick plates for welding, weldability is reduced, easily causing cracking at the weld root. Summary of the Invention

[0006] This invention proposes a rock drill crank arm and a rock drill, which are used to achieve lightweighting of the rock drill crank arm.

[0007] This invention provides a rock drill crank arm, comprising:

[0008] The first connecting portion includes a first mounting hole;

[0009] The second connecting portion includes a second mounting hole; the central axis of the second mounting hole is parallel to the central axis of the first mounting hole; and

[0010] The third connecting part includes a third mounting hole, the central axis of which is perpendicular to the central axis of the first mounting hole.

[0011] In some embodiments, the rock drill crank arm further includes:

[0012] The connecting column is integral with the third connecting part; one axial end of the connecting column is fixedly connected to the third connecting part and is integral with it, and the other axial end of the connecting column is fixedly connected to both the second connecting part and the first connecting part and is integral with it.

[0013] In some embodiments, the first connecting portion is configured as a plate, one end of the first connecting portion is fixedly connected to the connecting post and is integral thereon, and the other end of the first connecting portion is provided with the first mounting hole.

[0014] In some embodiments, the first connecting portions are arranged in pairs, with the two first connecting portions being parallel and located at different axial positions of the connecting post; the line connecting the centers of the first mounting holes of each first connecting portion is parallel to the central axis of the connecting post.

[0015] In some embodiments, the rock drill crank arm further includes:

[0016] The first reinforcing rib is disposed between the two first connecting parts, and the first reinforcing rib is fixedly connected to each of the first connecting parts and the connecting column and is integral with them.

[0017] In some embodiments, the rock drill crank arm further includes:

[0018] The reinforcing member has one end fixedly connected to and integrally formed with the first connecting part near the third connecting part among the two first connecting parts, and the other end fixedly connected to and integrally formed with the third connecting part; one side of the reinforcing member is also fixedly connected to and integrally formed with the connecting post.

[0019] In some embodiments, the second connecting portion is configured as a plate, one end of the second connecting portion is fixedly connected to the connecting post and is integral with it, and the other end of the second connecting portion is provided with the second mounting hole.

[0020] In some embodiments, the second connecting parts are arranged in pairs, and the line connecting the centers of the second mounting holes of the two second connecting parts is parallel to the central axis of the connecting post.

[0021] In some embodiments, two second connecting portions are located between two first connecting portions; and the distance between one of the first connecting portions and one of the second connecting portions is L1, and the distance between the other first connecting portion and the other second connecting portion is L2, wherein L1 and L2 are equal.

[0022] In some embodiments, the rock drill crank arm further includes:

[0023] The second reinforcing rib is disposed between the two second connecting parts. The second reinforcing rib is fixedly connected to each of the second connecting parts and the connecting column and is integral with them.

[0024] In some embodiments, the first connecting portion and the second connecting portion are located at different circumferential positions of the connecting post.

[0025] In some embodiments, the central angles corresponding to the center positions of the first connecting portion and the second connecting portion in the circumferential direction of the connecting post are 85° to 95°.

[0026] In some embodiments, the third connecting portion is constructed as a cylinder, and the third mounting hole extends through the axial direction of the third connecting portion; the connecting post is fixedly connected to the outer surface of the third connecting portion and the connection position is located at the middle position in the axial direction of the third connecting portion.

[0027] In some embodiments, the third connecting portion smoothly transitions to the connecting post.

[0028] In some embodiments, the rock drill crank arm is cast.

[0029] This invention also provides a rock drilling vehicle, including the rock drilling vehicle crank arm provided by any of the technical solutions of this invention.

[0030] The rock drill crank arm provided by the above technical solution significantly reduces the stress borne by the crank arm after it is installed by changing the relative relationship of the mounting holes of the first, second, and third connecting parts. Furthermore, compared to rock drill crank arms in the prior art, the weight of the rock drill crank arm provided by this embodiment can be reduced by more than 50%, and its size can also be reduced by more than 50% compared to the prior art. This technical solution, while maintaining the load-bearing capacity of the rock drill crank arm, reduces the stress borne by it, thus achieving lightweighting and miniaturization of the rock drill crank arm. Attached Figure Description

[0031] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0032] Figure 1 This is a front view schematic diagram of the rock drill arm installation state provided in an embodiment of the present invention.

[0033] Figure 2 This is a top view schematic diagram of the rock drill arm installation state provided in an embodiment of the present invention.

[0034] Figure 3This is a schematic diagram of the three-dimensional structure of the rock drill crank arm provided in an embodiment of the present invention.

[0035] Figure 4 This is a front view schematic diagram of the rock drill crank arm provided in an embodiment of the present invention.

[0036] Figure 5 This is a top view schematic diagram of the rock drill crank arm provided in an embodiment of the present invention.

[0037] Figure 6 This is a side view schematic diagram of the rock drill crank arm provided in an embodiment of the present invention.

[0038] Figure label:

[0039] 10. Rock drill boom; 20. Chassis; 30. Propulsion system;

[0040] 1. First connecting part; 2. Second connecting part; 3. Third connecting part; 4. Connecting post; 5. First reinforcing rib; 6. Reinforcing member; 7. Second reinforcing rib;

[0041] 11. First mounting hole;

[0042] 21. Second mounting hole;

[0043] 31. Third mounting hole. Detailed Implementation

[0044] The following is combined with Figures 1-6 The technical solution provided by this invention will be described in more detail below.

[0045] See Figure 1 and Figure 2 This invention provides a rock drill crank arm 10, which is integrally formed and manufactured using methods such as casting. The rock drill crank arm 10 is positioned between the rock drill frame 20 and the propulsion device 30, and is used to mount the propulsion device 30 to the frame 20. The rock drill crank arm 10 has an asymmetrical structure.

[0046] See Figure 3 The rock drill arm 10 includes a first connecting part 1, a second connecting part 2, and a third connecting part 3. The first connecting part 1, the second connecting part 2, and the third connecting part 3 are integrally formed, specifically by casting. The first connecting part 1 includes a first mounting hole 11. The second connecting part 2 includes a second mounting hole 21; the central axis of the second mounting hole 21 is parallel to the central axis of the first mounting hole 11. The third connecting part 3 includes a third mounting hole 31, the central axis of which is perpendicular to the central axis of the first mounting hole 11.

[0047] The first connecting part 1 and the second connecting part 2 are used to directly or indirectly install the propulsion device 30, and the third connecting part 3 is used to directly or indirectly connect with the frame 20.

[0048] The above technical solution, by changing the relative relationship of the mounting holes of the first connecting part 1, the second connecting part 2, and the third connecting part 3, significantly reduces the stress borne by the rock drill crank arm 10 after it is installed. Furthermore, compared to rock drill crank arms in the prior art, the weight of the rock drill crank arm 10 provided in this embodiment can be reduced by more than 50%, and the size of the rock drill crank arm 10 can also be reduced by more than 50% compared to the prior art. This technical solution, while maintaining the load-bearing capacity of the rock drill crank arm 10, reduces the stress borne by the rock drill crank arm 10, and also achieves lightweighting and miniaturization of the rock drill crank arm 10.

[0049] See also Figure 3 In some embodiments, the rock drill arm 10 further includes a connecting column 4, which is integral with the third connecting part 3. The connecting column 4 is specifically a hollow cylinder, which is not only very lightweight but also has a very high load-bearing capacity, and strong resistance to bending and compression. The cylindrical connecting column 4 significantly increases the strength of the rock drill arm 10. The connecting column 4 is used to install the first connecting part 1 and the second connecting part 2. The length of the connecting column 4 meets the installation requirements of the first connecting part 1 and the second connecting part 2.

[0050] One axial end of the connecting column 4 is fixedly connected to the third connecting part 3 and is integral with it. The other axial end of the connecting column 4 is fixedly connected to both the second connecting part 2 and the third connecting part 3 and is integral with them.

[0051] By setting the connecting post 4, the shape and connection relationship of the first connecting part 1, the second connecting part 2, and the third connecting part 3 can be simplified. The first connecting part 1, the second connecting part 2, and the third connecting part 3 do not need to be directly fixed to each other, but are all fixed to the connecting post 4. This simplifies the manufacturing difficulty of the components and the connection relationship between the components. It also allows for the targeted design of the structural shape of the first connecting part 1, the second connecting part 2, and the third connecting part 3, so as to make the load-bearing capacity of the rock drill crank arm 10 stronger.

[0052] In some embodiments, at least one of the first connecting portion 1, the second connecting portion 2, and the third connecting portion 3 smoothly transitions with the connecting post 4. To enhance the load-bearing capacity of the rock drill crank arm 10 and reduce stress concentration, some embodiments of the present invention use the example where each of the first connecting portion 1, the second connecting portion 2, and the third connecting portion 3 smoothly transitions with the connecting post 4. During the casting and manufacturing process of the rock drill crank arm 10, smooth transition surfaces are provided at the connection points between the first connecting portion 1, the second connecting portion 2, and the third connecting portion 3 and the connecting post 4 to achieve a smooth transition between components, thereby optimizing the performance of the rock drill crank arm 10 and improving its load-bearing capacity.

[0053] See Figure 3 and Figure 4 In some embodiments, the first connecting part 1 is constructed as a plate, one end of the first connecting part 1 is fixedly connected to the connecting post 4 and is integral with it, and the other end of the first connecting part 1 is provided with a first mounting hole 11. The end of the other end of the first connecting part 1 is an arc-shaped surface, which makes it less likely for stress concentration to form in the first connecting part 1 during the manufacturing process. Therefore, the structure of the first connecting part 1 is better and the load-bearing capacity is stronger.

[0054] The first connecting part 1 is used for direct or indirect connection with the propulsion device 30. To make the connection between the first connecting part 1 and other components more stable and reliable, the first connecting parts 1 are arranged in pairs, and the two first connecting parts 1 are parallel. The two first connecting parts 1 are located at different axial positions of the connecting column 4; the two first connecting parts 1 are distributed on the surface of the connecting column 4. The line P1 connecting the centers of the first mounting holes 11 of each first connecting part 1 is parallel to the central axis P0 of the connecting column 4.

[0055] The line connecting the centers of the holes, P1, is parallel to the central axis, P0. This arrangement can reduce the off-center load on the rock drill arm 10 after installation, making the load distribution of the rock drill arm 10 more reasonable, and thus making the rock drill arm 10 more capable of bearing load.

[0056] See Figure 3 and Figure 4To further increase the load-bearing capacity of the rock drill crank arm 10, in some embodiments, the rock drill crank arm 10 also includes a first reinforcing rib 5. The first reinforcing rib 5 is a long strip plate. The first reinforcing rib 5 is disposed between two first connecting parts 1, and the first reinforcing rib 5 is fixedly connected to each of the first connecting parts 1 and the connecting column 4 and is integrally formed. Specifically, one end of the first reinforcing rib 5 is integrally cast with one of the first connecting parts 1, and the other end of the first reinforcing rib 5 is integrally cast with the other first connecting part 1. The side of the first reinforcing rib 5 away from the connecting column 4 is constructed as a concave arc shape, and the side of the first reinforcing rib 5 facing the connecting column 4 is integrally cast with the connecting column 4. This structure of the first reinforcing rib 5 effectively increases the load-bearing capacity of the rock drill crank arm 10 at the first connecting part 1, and is lightweight, effectively balancing the requirements of load-bearing capacity and lightweight design.

[0057] See also Figure 3 and Figure 4 In some embodiments, the rock drill arm 10 further includes a reinforcing member 6. Specifically, the reinforcing member 6 is a long strip-shaped plate. As described above, the two first connecting parts 1 are denoted as A and B, respectively. Figure 4 The first connecting part 1 marked with A is closer to the third connecting part 3. Figure 4 The first connecting part 1, marked A, is far from the third connecting part 3. The reinforcing member 6 is located... Figure 4 Between the first connecting part 1 and the third connecting part 3 marked A. One end of the reinforcing member 6 is connected to... Figure 4 The first connecting part 1, marked A, is integrally cast. The other end of the reinforcing member 6 is integrally cast with the third connecting part 3. The side of the reinforcing member 6 away from the connecting post 4 is constructed as a flat or concave arc surface. The side of the reinforcing member 6 facing the connecting post 4 is integrally cast with the connecting post 4. The other end of the reinforcing member 6 is fixedly connected to the third connecting part 3 and is integral. One side of the reinforcing member 6 is also fixedly connected to the connecting post 4 and is integral. The shape of the reinforcing member 6 is similar to an airfoil. The reinforcing member 6 smoothly transitions with both the first connecting part 1 and the third connecting part 3, which makes the load distribution of the rock drill crank arm 10 reasonable and its load-bearing capacity strong.

[0058] See Figure 4 The height H1 of the reinforcing member 6 is greater than the height H2 of the first reinforcing rib 5. Here, the height H1 of the reinforcing member 6 refers to its maximum height in the front view direction. The height H2 of the first reinforcing rib 5 refers to its maximum height in the front view direction.

[0059] See Figures 3 to 5In some embodiments, the second connecting part 2 is constructed as a plate, with one end of the second connecting part 2 fixedly connected to the connecting post 4 and integrally formed, and the other end of the second connecting part 2 provided with a second mounting hole 21. The end of the other end of the second connecting part 2 is an arc-shaped surface, which makes it less likely for stress concentration to form in the second connecting part 2 during the manufacturing process, so the structure of the second connecting part 2 is superior and its load-bearing capacity is stronger.

[0060] The second connecting part 2 is also used to connect directly or indirectly with the propulsion device 30. In order to make the connection between the second connecting part 2 and other components more stable and reliable, in some embodiments, the second connecting parts 2 are arranged in pairs, and the line connecting the center of the second mounting holes 21 of the two second connecting parts 2 is parallel to the central axis of the connecting column 4.

[0061] See Figure 4 In some embodiments, two second connecting portions 2 are located between two first connecting portions 1; the two second connecting portions 2 are distributed on the surface of the connecting post 4. The two second connecting portions 2 are respectively denoted as C and D. Furthermore, Figure 4 The first connecting part 1 marked A in the middle and Figure 4 The distance of the second connecting part 2 marked C is L1. Figure 4 The first connecting part 1 marked B in the middle and Figure 4 The distance between the second connecting parts 2 marked D is L2, and L1 and L2 are equal. The two second connecting parts 2 are arranged between the two first connecting parts 1, and the plane where the middle position of the two first connecting parts 1 is located coincides with the plane where the middle position of the two second connecting parts 2 is located. This can reduce the off-center load phenomenon experienced by the rock drill arm 10 after installation.

[0062] See Figure 3 and Figure 4 In some embodiments, the rock drill crank arm 10 further includes a second reinforcing rib 7, specifically, the second reinforcing rib 7 is a long strip-shaped plate. The second reinforcing rib 7 is disposed between the two second connecting parts 2, and the second reinforcing rib 7 is fixedly connected to each of the second connecting parts 2 and the connecting column 4 and is integrally formed. The second reinforcing rib 7, the two second connecting parts 2, and the connecting column 4 are all integrally cast. The side of the second reinforcing rib 7 away from the connecting column 4 is constructed as a concave arc shape. This structure of the second reinforcing rib 7 effectively increases the load-bearing capacity of the rock drill crank arm 10 at the second connecting part 2, and is lightweight, effectively balancing the requirements of load-bearing capacity and lightweight design.

[0063] In some embodiments, the second reinforcing rib 7 and the two second connecting portions 2 generally form an H-shape. This shape can greatly increase the load-bearing capacity of the rock drill arm 10 at the second connecting portion 2, so that the rock drill arm 10 has a higher load-bearing capacity with a lighter weight.

[0064] In some embodiments, the first connecting part 1 and the second connecting part 2 are located at different circumferential positions of the connecting post 4.

[0065] In some embodiments, the central angle θ corresponding to the center position of the first connecting part 1 and the second connecting part 2 in the circumferential direction of the connecting post 4 is 85° to 95°, specifically, for example, 85°, 90°, 95°, etc. (See [reference]). Figure 6 Since both the first connecting part 1 and the second connecting part 2 have width, the central angle referred to here is the central angle between the surface position of the connecting post 4 corresponding to the center of the width direction of the first connecting part 1 and the surface position of the connecting post 4 corresponding to the center of the width direction of the second connecting part 2. By adopting the above-mentioned included angle, the requirements for installation, manufacturing, and other aspects of the first connecting part 1 and the second connecting part 2 can be balanced.

[0066] In some embodiments, the third connecting portion 3 is constructed as a cylinder, and the third mounting hole 31 penetrates the axial direction of the third connecting portion 3. The connecting post 4 is fixedly connected to the outer surface of the third connecting portion 3, and the connection position is located at the middle position in the axial direction of the third connecting portion 3. See also Figure 3 A ring of connecting holes 32 is provided around the third mounting hole 31. The third mounting hole 31 is the hole with the largest inner diameter of the third connecting part 3. The rock drill arm 10 is installed by directly or indirectly connecting to the frame 20 through the third mounting hole 31.

[0067] In the above technical solution, the connecting column 4 is fixedly connected to the outer surface of the third connecting part 3 and the connection position is located at the middle position in the axial direction of the third connecting part 3. The third mounting hole 31 has no offset relative to the central axis of the connecting column 4. This structure greatly reduces the bending moment experienced by the rock drill crank arm 10 during use, greatly improves the stress condition of the rock drill crank arm 10, and greatly enhances the load-bearing capacity of the rock drill crank arm 10.

[0068] See Figure 1 and Figure 2 The present invention also provides a rock drilling vehicle, including the rock drilling vehicle crank arm 10 provided by any of the technical solutions of the present invention.

[0069] The rock drilling vehicle provided by the above technical solution has a rock drilling vehicle crank arm 10 with a topology optimization design and is formed by casting to form an integral structure. Its structure is not only lightweight, but also has high bending stiffness and strength. It effectively solves the design contradiction between the weight of the rock drilling vehicle crank arm 10 and the structural stiffness and strength, which is conducive to the lightweight design of the rock drilling vehicle crank arm structure, improves the reliability of the rock drilling vehicle crank arm structure, and enhances the operational safety and stability of the whole vehicle.

[0070] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to facilitate the description of this invention and to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rock drilling vehicle crank arm, characterized in that, The rock drill crank arm has an asymmetrical structure and is integrally formed. The rock drill crank arm includes: The first connecting part (1) includes a first mounting hole (11); The second connecting part (2) includes a second mounting hole (21); the central axis of the second mounting hole (21) is parallel to the central axis of the first mounting hole (11); The third connecting portion (3) includes a third mounting hole (31), the central axis of which is perpendicular to the central axis of the first mounting hole (11); and The connecting column (4) has one axial end fixedly connected to the third connecting part (3) and is integral with it; the other axial end of the connecting column (4) is fixedly connected to the second connecting part (2) and the first connecting part (1) and is integral with it; the connecting column (4) is a hollow cylinder. The first connecting part (1) is constructed as a plate. One end of the first connecting part (1) is fixedly connected to the connecting post (4) and is integral with it. The other end of the first connecting part (1) is provided with the first mounting hole (11). The second connecting part (2) is constructed as a plate. One end of the second connecting part (2) is fixedly connected to the connecting post (4) and is integral with it. The other end of the second connecting part (2) is provided with the second mounting hole (21).

2. The rock drilling machine crank arm according to claim 1, characterized in that, The first connecting parts (1) are arranged in pairs, and the two first connecting parts (1) are parallel and located at different positions in the axial direction of the connecting column (4); the line connecting the center of the first mounting hole (11) of each first connecting part (1) is parallel to the central axis of the connecting column (4).

3. The rock drilling machine crank arm according to claim 2, characterized in that, Also includes: The first reinforcing rib (5) is disposed between the two first connecting parts (1); the first reinforcing rib (5) is fixedly connected to each of the first connecting parts (1) and the connecting column (4) and is integral.

4. The rock drilling machine crank arm according to claim 1, characterized in that, Also includes: The reinforcing member (6) is fixedly connected at one end to the first connecting part (1) near the third connecting part (3) of the two first connecting parts (1) and is integral with it; the other end is fixedly connected to the third connecting part (3) and is integral with it; one side of the reinforcing member (6) is also fixedly connected to the connecting post (4) and is integral with it.

5. The rock drilling machine crank arm according to claim 1, characterized in that, The second connecting parts (2) are arranged in pairs, and the line connecting the center of the second mounting hole (21) of the two second connecting parts (2) is parallel to the central axis of the connecting column (4).

6. The rock drilling machine crank arm according to claim 5, characterized in that, Two second connecting parts (2) are located between two first connecting parts (1); and the distance between one of the first connecting parts (1) and one of the second connecting parts (2) is L1, and the distance between the other first connecting part (1) and the other second connecting part (2) is L2, with L1 and L2 being equal.

7. The rock drilling machine crank arm according to claim 5, characterized in that, Also includes: The second reinforcing rib (7) is disposed between the two second connecting parts (2); the second reinforcing rib (7) is fixedly connected to each of the second connecting parts (2) and the connecting column (4) and is integral.

8. The rock drilling machine crank arm according to claim 1, characterized in that, The first connecting part (1) and the second connecting part (2) are located at different circumferential positions of the connecting post (4).

9. The rock drilling machine crank arm according to claim 8, characterized in that, The central angles of the first connecting part (1) and the second connecting part (2) at the center position of the connecting post (4) in the circumferential direction are 85° to 95°.

10. The rock drilling vehicle crank arm according to claim 1, characterized in that, The third connecting part (3) is constructed in a cylindrical shape, and the third mounting hole (31) penetrates the axial direction of the third connecting part (3); the connecting post (4) is fixedly connected to the outer surface of the third connecting part (3) and the connection position is located at the middle position in the axial direction of the third connecting part (3).

11. The rock drilling vehicle crank arm according to claim 1, characterized in that, The third connecting part (3) and the connecting post (4) are smoothly connected.

12. The rock drilling vehicle crank arm according to claim 1, characterized in that, The rock drill's crank arm is cast.

13. A rock drilling vehicle, characterized in that, Includes the rock drill crank arm (10) as described in any one of claims 1 to 12.

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