Impact mechanism and impact wrench applying same

Abstract

The invention relates to the technical field of impact wrenches, in particular to an impact mechanism and an impact wrench applying the same, and the impact mechanism comprises an output shaft and a striking block used for driving the output shaft to rotate; the output shaft comprises a shaft body and a flange arranged at one end of the shaft body, striking blades are arranged on the flange, and striking surfaces are arranged on the side walls of the striking blades; the hit surface is tangent to the side wall of the flange; the striking block is provided with a striking boss, the striking boss is provided with a striking surface matched with the hit surface, and the striking surface strikes the hit surface to enable the output shaft to rotate around the axis of the output shaft; when the striking face makes contact with the hit face, the striking face is attached to the hit face in parallel. The impact-resistant striking blade has the effects that the impact resistance of the striking blade is improved, and the breaking condition of the striking blade is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of impact wrenches, in particular to an impact mechanism and an impact wrench applying the same. BACKGROUND

[0002] The impact electric wrench is composed of a motor, a planetary gear reducer, a ball screw impact mechanism, a forward and reverse power switch, a power coupling device and a motorized sleeve.

[0003] At present, a common impact wrench on the market is disclosed in CN112440237A, which comprises a main body having a striking mechanism, an anvil protruding from the main body, a hammering member striking the anvil in the rotation direction, and a motor rotating the hammering member. The anvil has a blade portion for the hammering member to contact, a cylindrical portion with the protruding direction of the anvil as the front and arranged in front of the blade portion, a square column portion arranged in front of the cylindrical portion, and a cutout surface formed in each corner of the square column portion along the axial direction of the anvil. A gouging portion is arranged at the rear end of each cutout surface. The striking surface of the blade portion is horizontally arranged, and there is a sharp corner or an R corner at the connection between the blade portion and the anvil, which causes stress concentration and easily breaks when the power is high. Therefore, there is an urgent need for an impact mechanism with high impact resistance. SUMMARY

[0004] To solve the above technical problems, the present application provides an impact mechanism which has the advantages of improving its impact resistance and reducing the occurrence of broken striking blades.

[0005] To achieve the above-mentioned purposes, the technical solutions of the present application are as follows: An impact mechanism comprises an output shaft and a striking block for driving the output shaft to rotate. The output shaft comprises a shaft body and a flange arranged at one end of the shaft body, and the flange is provided with a striking blade, and the side wall of the striking blade is provided with a striking surface; the striking surface is tangentially arranged with the side wall of the flange; The striking block is provided with a striking boss, and the striking boss is provided with a striking surface matched with the striking surface, and the striking surface makes the output shaft rotate around its own axis by striking the striking surface; when the striking surface contacts the striking surface, the striking surface is parallel to the striking surface.

[0006] The above technical scheme is realized, that is, when the beating block is driven by the electric driving mechanism to rotate in a pulse mode, the beating boss drives the beating surface to beat the receiving surface in a pulse mode, so that the output shaft rotates around its own axis. The flange is arranged to strengthen the shaft body, thereby ensuring the structural stability. Meanwhile, the receiving surface is arranged tangentially to the side wall of the flange, so that there is no R angle and sharp angle between the receiving surface and the flange, thereby avoiding the stress concentration and preventing the beating blade from being broken.

[0007] As a preferred scheme of the present application, when the beating blade rotates to be vertically upward, the distance between the vertical plane passing through the central axis and the receiving surface gradually increases in the direction close to the shaft body.

[0008] The above technical scheme is realized, that is, the receiving surface is arranged to be relatively inclined, so that when the beating surface knocks the receiving surface, the knocking force F acts on the beating blade perpendicularly to the receiving surface. The knocking force F can be decomposed into the compressive stress for compressing the beating blade arranged radially to the shaft body and the tensile stress for driving the beating blade to rotate perpendicularly to the compressive stress. The tensile stress generated by the impact must first “offset” the compressive stress generated by the impact, and then the material can actually bear the tensile stress. This is equivalent to increasing the “threshold” of the material to start to bear the tensile stress, thereby further improving the impact resistance of the beating blade and ensuring the structural strength.

[0009] As a preferred scheme of the present application, the beating blade is provided with a pair of symmetrically arranged receiving surfaces, and the included angle a between the two receiving surfaces is 30°-60°.

[0010] The above technical scheme is realized, that is, the structural strength is ensured, and the ratio of the diameter of the flange to the length of the beating blade is limited to be neither too large to reduce the stress moment and cause the output impact force to be insufficient, nor too small to cause the beating blade to be too long and the impact force to be too large due to the increase of the moment, thereby causing the beating blade to be easily damaged.

[0011] As a preferred scheme of the present application, the included angle a is 45°.

[0012] The above technical scheme is realized to maintain the structural strength while ensuring the output impact force.

[0013] As a preferred scheme of the present application, the beating blade is symmetrically arranged with a pair of beating blades along the shaft body.

[0014] The above technical scheme is realized, so that the frequency of the output shaft is improved by the beating block, thereby improving the output pulse of the output shaft.

[0015] As a preferred solution of the present application, two beating bosses are provided, and the two beating bosses are arranged radially symmetrically along the shaft body.

[0016] The above technical solution is implemented, and then the impulse rotation of the beating block can act on the beating blades through the two beating bosses at the same time, so that the beating force can be evenly distributed on the two beating blades, thereby reducing the force borne by each beating blade, thereby ensuring the service life of the beating blade. At the same time, the compressive stress borne by the two beating blades is symmetrically balanced, and does not cause eccentric wear of the output shaft. Two beating surfaces are symmetrically arranged on each beating boss, so that the same beating boss can knock the two beating surfaces on the beating boss in positive and negative directions, thereby driving the output shaft to rotate in positive and negative directions.

[0017] As a preferred solution of the present application, a pair of symmetrically arranged beating surfaces are arranged on each beating boss, and the included angle b between the beating surfaces is 105°-135°.

[0018] The above technical solution is implemented, so that the beating surfaces beat in an interval, thereby improving the output efficiency, while ensuring a certain beating block storage space, thereby ensuring the beating force, so as to achieve the effect of ensuring the beating interval and the output force.

[0019] As a preferred solution of the present application, the included angle b is 120°. The above technical solution is implemented, and the optimal output interval and output force are achieved.

[0020] As a preferred solution of the present application, a fence is arranged between the beating bosses.

[0021] The above technical solution is implemented, so that the fence plays a connecting and reinforcing role between the beating bosses, thereby reducing the occurrence of deformation of the beating bosses due to impact.

[0022] The present application also provides an impact plate book, which applies the above impact mechanism and has the effects of the above impact structure.

[0023] In summary, the present application includes at least one of the following beneficial technical effects: 1. When the hitting block is pulsed to rotate under the driving of the electric driving mechanism, the hitting boss drives the hitting surface to pulse hit the hit surface, so as to rotate the output shaft around its axis. The flange is arranged to strengthen the shaft body, so as to ensure the structural stability. Meanwhile, the hit surface is tangent to the side wall of the flange, so that there is no R angle and sharp angle between the hit surface and the flange, so that no stress concentration occurs, thereby preventing the hitting blade from breaking; the hitting surface is arranged in parallel with the hit surface, so that the hitting surface is attached to the hit surface, so as to ensure the stress area between the two, thereby further ensuring that the hitting blade will not be damaged due to stress concentration. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0025] Figure 1 It is a schematic diagram of the overall structure of the embodiment of the present application.

[0026] Figure 2 It is a top view of the embodiment of the present application.

[0027] Figure 3 It is a top view of the output shaft in the embodiment of the present application.

[0028] Figure 4 It is a top view of the hitting block in the embodiment of the present application.

[0029] Reference signs: 1, output shaft; 11, flange; 12, hitting blade; 13, hit surface; 14, shaft body; 2, hitting block; 21, hitting boss; 22, hitting surface; 23, fence. DETAILED DESCRIPTION

[0030] The following will be described in combination with the drawings Figures 1-4 The present application will be further described in detail.

[0031] The embodiment of the present application discloses an impact mechanism. Referring to Figures 1-4 , the impact mechanism comprises an output shaft 1 and a hitting block 2 for driving the output shaft 1 to rotate; the output shaft 1 is rotated by the hitting block 2, so as to drive the output shaft 1 to rotate around its axis.

[0032] The output shaft 1 comprises a shaft body and a flange 11 arranged at one end of the shaft body, and a beating blade 12 is arranged on the flange 11, and a receiving surface 13 is arranged on the side wall of the beating blade 12, and the receiving surface 13 is tangentially connected with the side wall of the flange 11; wherein the arrangement of the flange 11 plays a role in strengthening the shaft body, thereby ensuring the structural stability, and at the same time, the receiving surface 13 is tangentially arranged with the side wall of the flange 11, thereby making the receiving surface 13 and the flange 11 free of R angle and sharp angle, thereby avoiding the occurrence of stress concentration, thereby preventing the occurrence of the breaking of the beating blade 12.

[0033] The beating block 2 is provided with a beating boss 21, and a beating surface 22 cooperating with the receiving surface 13 is arranged on the beating boss 21, that is, when the beating block 2 is driven by the electric drive mechanism to rotate in a pulse manner, the beating boss 21 drives the beating surface 22 to hit the receiving surface 13 in a pulse manner, thereby rotating the output shaft 1 around its own axis. When the beating surface 22 contacts the receiving surface 13, the beating surface 22 is arranged parallel to the receiving surface 13, thereby making the beating surface 22 adhere to the receiving surface 13, thereby ensuring the force bearing area therebetween, thereby further ensuring that the beating blade 12 will not be damaged due to stress concentration.

[0034] When the beating blade 12 rotates to be vertically upward, the distance between the vertical plane passing through the central axis and the receiving surface 13 gradually increases along the direction close to the shaft body, that is, the receiving surface 13 is arranged relatively obliquely, thereby making the knocking force F act on the beating blade 12 along the direction perpendicular to the receiving surface when the beating surface 22 knocks the receiving surface 13, and the knocking force F can be decomposed into a compressive stress for compressing the beating blade 12 arranged radially to the shaft body and a tensile stress for driving the beating blade 12 to rotate perpendicular to the compressive stress, and the tensile stress generated by the impact must first "offset" the compressive stress generated by the impact, and then the material can actually bear the tensile stress. This is equivalent to increasing the "threshold" at which the material begins to bear tensile stress and break, thereby further improving the impact resistance of the beating blade 12 and ensuring its structural strength.

[0035] The beating blade 12 is provided with a pair of symmetrically arranged receiving surfaces 13. The entire beating blade 12 is arranged in a trapezoidal shape, thereby ensuring its structural strength while reducing the size of the beating blade 12, thereby facilitating miniaturization. The symmetrically arranged two receiving surfaces 13 enable the beating blade 12 to be knocked in both directions, thereby realizing forward and reverse rotation. The included angle a between the two receiving surfaces 13 is 30°-60°, that is, while ensuring the structural strength, the ratio of the diameter of the flange 11 and the length of the beating blade 12 is limited to be not too large to reduce the stress moment and thereby cause the output impact force to be insufficient, and at the same time, the ratio is not too small to cause the beating blade 12 to be too long and thereby cause the impact force to be too large due to the increase of the moment of force, thereby causing the beating blade 12 to be easily damaged. In the embodiment, the included angle a is 45° to maintain the structural strength while ensuring the output impact force.

[0036] The beating blades 12 are arranged in pairs along the shaft body. Thus, the output shaft 1 is subjected to the frequency of the beating block 2, thereby improving the output pulse of the output shaft 1.

[0037] The beating boss 21 is provided with two beating bosses 21, and the two beating bosses 21 are arranged radially symmetrically along the shaft body. Thus, when the beating block 2 rotates in a pulse manner, the two beating bosses 21 can simultaneously act on the beating blades 12, thereby making the beating force evenly distributed on the two beating blades 12, so as to reduce the force on each beating blade 12, thereby ensuring the service life of the beating blade 12. At the same time, the pressure stress on the two beating blades 12 is symmetrically balanced, so as not to cause the output shaft 1 to produce eccentric wear. Two beating surfaces 22 are symmetrically arranged on each beating boss 21, thereby making the same beating boss 21 knock the two beating surfaces 13 on the beating boss 21 in a positive and negative manner, thereby driving the output shaft 1 to rotate in a positive and negative manner. The included angle B between the two beating surfaces 22 is 105°-135°, thereby making the beating surfaces 22 beat in an interval, thereby improving the output efficiency, while ensuring a certain beating block 2 power storage space, so as to ensure the beating force, thereby achieving the effect of ensuring the beating interval and the output force. In the embodiment, the included angle b is 120°, which can achieve the optimal output interval and output force.

[0038] The fence 23 is arranged between the beating bosses 21. Thus, the fence 23 plays a connecting and reinforcing role between the beating bosses, thereby reducing the deformation of the beating boss 21 due to impact.

[0039] The implementation principle of the impact mechanism in the embodiment of the application is that when the striking block 2 is driven to rotate in a pulse manner by the electric driving mechanism, the striking boss 21 drives the striking surface 22 to impact the receiving surface 13 in a pulse manner, so as to drive the output shaft 1 to rotate around the axis thereof. The flange 11 is arranged to strengthen the shaft body, thereby ensuring the structural stability. Meanwhile, the receiving surface 13 is arranged to be tangent to the side wall of the flange 11, so that there is no R angle and sharp angle between the receiving surface 13 and the flange 11, thereby preventing the stress concentration and the fracture of the striking blade 12. The included angle a between the two receiving surfaces 13 is 30°-60°, that is, the structural strength is ensured, and meanwhile, the ratio of the diameter of the flange 11 and the length of the striking blade 12 is limited to be not too large, so as to prevent the reduction of the stress moment and the insufficient output impact force. Meanwhile, the ratio is also limited to be not too small, so as to prevent the striking blade 12 from being too long, thereby preventing the increase of the stress moment and the excessive impact force under the impact force, and preventing the striking blade 12 from being damaged. The included angle B between the two striking surfaces 22 is 105°-135°, so that the striking surfaces 22 are struck in an interval manner, thereby improving the output efficiency, ensuring the power storage space of the striking block 2, and ensuring the striking force, so as to ensure the output force and the interval of the striking surfaces 22. In the embodiment, the included angle B is 120°, so as to achieve the optimal output interval and output force.

[0040] The embodiment of the application also provides an impact wrench, which comprises the impact mechanism described above, thereby having all the beneficial technical effects of the impact mechanism, and details are not described herein.

[0041] The above are the preferred embodiments of the application, and do not limit the protection scope of the application, so that: any equivalent changes made according to the structure, shape, principle of the application should be covered in the protection scope of the application.

Claims

1. An impact mechanism, characterized in that: It includes an output shaft (1) and a striking block (2) for driving the output shaft (1) to rotate; The output shaft (1) includes a shaft body and a flange (11) disposed at one end of the shaft body. The flange (11) is provided with an impact blade (12), and the side wall of the impact blade (12) is provided with an impact surface (13). The impact surface (13) is tangential to the side wall of the flange (11). The striking block (2) is provided with a striking boss (21), and the striking boss (21) is provided with a striking surface (22) that cooperates with the striking surface (13). The striking surface (22) strikes the striking surface (13) to make the output shaft (1) rotate around its own axis.

2. The impact mechanism according to claim 1, characterized in that: When the striking blade (12) rotates to a vertically upward position, the distance between the vertical plane passing through the central axis and the impact surface (13) gradually increases along the direction close to the axis.

3. The impact mechanism according to claim 1, characterized in that: The angle α between the impact surface (13) and the vertical plane is between 30° and 60°.

4. The impact mechanism according to claim 1, characterized in that: The included angle α is 45°.

5. The impact mechanism according to claim 1, characterized in that: The striking blade (12) is provided with a pair of symmetrically arranged impact surfaces (13).

6. The impact mechanism according to claim 1, characterized in that: The striking blades (12) are arranged symmetrically along the axis in a pair.

7. An impact mechanism according to claim 1, characterized in that: There are two striking bosses (21), and the two striking bosses (21) are arranged symmetrically along the radial direction of the shaft.

8. The impact mechanism according to claim 1, characterized in that: A fence (23) is provided between the striking protrusions (21).

9. An impact mechanism according to claim 1, characterized in that: When the striking surface (22) comes into contact with the impact surface (13), the striking surface (22) and the impact surface (13) are arranged parallel to each other.

10. An impact wrench comprising the impact structure of claim 1.

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