A reinforced hammer drill bit

Abstract

The utility model relates to a reinforced electric hammer drill bit, and the electric hammer drill bit comprises a drill body, the head of the drill body is provided with a cutting edge, and at least one chip removal groove is arranged on the drill body and extends along the axial direction of the drill body. The drill body further comprises at least one reinforcing rib which protrudes from the groove bottom surface of the chip removal groove, the spiral curve of the reinforcing rib is the same as the spiral curve of the chip removal groove, and the maximum width of the reinforcing rib is smaller than the width of the chip removal protrusion between the chip removal grooves. The electric hammer drill bit is provided with the reinforcing rib at the groove bottom of the chip removal groove, the reinforcing rib is consistent with the spiral curve of the chip removal groove, and the structural strength of the stress concentration area of the drill body can be strengthened in a targeted manner. The reinforcing rib reserves sufficient chip removal channels for the chip removal groove, and the accumulation of debris is avoided.

Description

Technical Field

[0001] This utility model relates to the field of drilling technology, and in particular to a reinforced electric hammer drill bit. Background Technology

[0002] Electric hammer drills are mainly used for drilling, grooving, or breaking up building materials. They utilize a combination of rotary cutting and reciprocating hammering motion, making them suitable for drilling into various hard materials such as concrete, brick, ceramic tiles, and building materials. The drill bit must simultaneously withstand high-frequency impact loads and rotary cutting forces. Existing electric hammer drill bits typically include a drill body with a cutting edge at the head and axially spaced chip grooves to remove drilling debris. The drill bit diameter is 5-10 mm. The chip grooves are spiral-shaped grooves formed by recesses on the drill rod surface. For example, the roller-formed chip groove electric hammer drill bit disclosed in publication number CN222790701U.

[0003] In deep hole drilling, the chip evacuation flute has a large pitch and a wide width. Reducing the flute size to increase strength would narrow the chip removal channel, leading to chip accumulation and drill bit jamming. This not only affects drilling efficiency but also accelerates cutting edge wear. Furthermore, slender drill bodies lack effective structural support during deep hole drilling, making them prone to radial wobble. This reduces drilling accuracy, and the additional friction generated by the wobble further shortens drill bit lifespan. Therefore, improvements are needed. Utility Model Content

[0004] To overcome the problems existing in related technologies, this utility model provides a reinforced electric hammer drill bit to solve the technical problem that the large pitch of the chip removal groove makes the drill body prone to bending, vibration, or even breakage.

[0005] According to a first aspect of the present invention, a reinforced electric hammer drill bit is provided. The electric hammer drill bit includes a drill body, the head of the drill body is provided with a cutting edge, and at least one chip removal groove is provided on the drill body extending along its axial direction. The drill body also includes at least one reinforcing rib protruding from the bottom surface of the chip removal groove. The helical curve of the reinforcing rib is the same as the helical curve of the chip removal groove, and the maximum width of the reinforcing rib is less than the width of the chip removal protrusion between the chip removal grooves.

[0006] In one embodiment, the ratio of the protrusion height of the reinforcing rib to the groove depth of the chip removal groove is B, where 0.5 ≤ B ≤ 1.

[0007] In one embodiment, the cross-sectional shape of the reinforcing rib is an arc, trapezoid, triangle, or rectangle.

[0008] In one embodiment, the helical length of the reinforcing rib is less than the helical length of the chip removal groove.

[0009] In one embodiment, the cross-sectional dimension of the reinforcing rib gradually decreases towards the end of the cutting edge.

[0010] In one embodiment, there are two chip removal grooves, and the bottom of each chip removal groove is provided with the reinforcing rib.

[0011] In one embodiment, the diameter of the drill body is 5mm-10mm, and the length of the drill body is greater than or equal to 600mm.

[0012] In one embodiment, the chip removal groove and the reinforcing rib are coated with a wear-resistant coating.

[0013] In one embodiment, the head of the drill body is provided with a fitting groove, and the drill bit further includes a carbide cutting tip embedded in the fitting groove. The carbide cutting tip and the drill body are welded and fixed together, and the opening of the chip removal groove is located on one side of the carbide cutting tip.

[0014] In one embodiment, the drill bit further includes a mounting portion located at the top of the drill body, the diameter of the mounting portion being larger than the diameter of the drill body, and the surface of the mounting portion having recessed guide grooves and at least two assembly grooves.

[0015] The technical solution provided by the embodiments of this utility model can include the following beneficial effects: By setting reinforcing ribs at the bottom of the chip removal groove, and the reinforcing ribs being consistent with the spiral curve of the chip removal groove, the drill bit can specifically enhance the structural strength of the stress concentration area of ​​the drill body. The reinforcing ribs reserve sufficient chip removal channels for the chip removal groove, avoiding chip accumulation. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0017] Figure 1 This is a perspective view of a hammer drill bit according to one embodiment.

[0018] Figure 2 This is a front view schematic diagram of a hammer drill bit according to one embodiment.

[0019] Figure 3 This is a schematic diagram of the head of a hammer drill bit according to one embodiment.

[0020] Figure 4 This is a schematic cross-sectional view of a hammer drill bit according to one embodiment.

[0021] Figure 5 This is a physical image of a hammer drill bit according to one embodiment.

[0022] In the figure, the drill body is 10; the chip removal groove is 11; the reinforcing rib is 12; the guide section is 121; the fitting groove is 13; the chip removal protrusion is 14; the carbide cutting head is 20; the mounting part is 30; the assembly groove is 31; and the guide groove is 32. Detailed Implementation

[0023] In the accompanying drawings of this utility model, the same or similar reference numerals correspond to the same or similar components. In the description of this utility model, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this utility model and simplifying 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, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this utility model. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0024] like Figures 1 to 3 As shown, this utility model discloses a reinforced electric hammer drill bit, which includes a drill body 10. The head of the drill body 10 is provided with a cutting edge, and at least one drill body 11 extends along its axial direction on the drill body 10. The cutting edge can drill material under the drive of the electric hammer, wherein the rock debris drill body 11 is discharged.

[0025] In this embodiment, the drill body 10 further includes at least one reinforcing rib 12 protruding from the bottom surface of the drill body 11. The helical curve of the reinforcing rib 12 is the same as that of the drill body 11, and the maximum width of the reinforcing rib 12 is less than the width of the chip removal protrusion 14 between the drill bodies 11. By providing the reinforcing rib 12 at the bottom of the drill body 11, the structural strength of the stress concentration area of ​​the drill body 10 can be specifically enhanced, and the strength of the drill body 10 is significantly improved, especially for slender drill bits with a diameter of 5mm-10mm and a length ≥600mm. The reinforcing rib 12 has the same helical curve as the drill body 11, and the drill body 11 has good chip removal function.

[0026] Furthermore, the reinforcing rib 12 is a local protrusion structure at the bottom of the drill body 11, wherein the portion of the drill body 11 between two adjacent drill bodies 11 forms a chip removal protrusion 14, the cross-sectional width of the chip removal protrusion 14 is greater than the cross-sectional width of the reinforcing rib 12, so as to form a multi-row reinforcing structure.

[0027] The ratio of the protrusion height of the reinforcing rib 12 to the groove depth of the drill body 11 is B, where 0.5 ≤ B ≤ 1. The maximum width of the reinforcing rib 12 is less than the width of the chip removal protrusion 14, and the ratio of the protrusion height of the reinforcing rib 12 to the groove depth of the drill body 11 is controlled at 0.5, 0.6, 0.7, 0.8, 0.9, and 1. This ensures that the protrusion height of the reinforcing rib 12 is less than or equal to the groove depth of the drill body 11, providing sufficient chip removal channels, preventing chip accumulation, and minimizing the impact on chip removal efficiency. In particular, when the ratio of the protrusion height of the reinforcing rib 12 to the groove depth of the drill body 11 is 0.5-0.7, the impact on chip removal efficiency is minimal, and the structural strengthening effect is good.

[0028] The reinforcing rib 12 protrudes from the bottom of the groove of the drill body 11. The cross-sectional shape of the reinforcing rib 12 is arc-shaped, trapezoidal, triangular, or rectangular. Different cross-sectional shapes can adapt to different drilling requirements. For example, the arc-shaped cross-section of the reinforcing rib 12 can reduce the accumulation of debris on the surface of the reinforcing rib 12 and improve the smoothness of chip removal, which is suitable for drilling brick and stone materials with small debris particles; the trapezoidal and rectangular cross-sections of the reinforcing rib 12 have stronger structural stability and are suitable for drilling concrete with large impact loads; the triangular cross-section of the reinforcing rib 12 has the advantages of both lightweight and strength, and is suitable for handheld electric hammer operation scenarios where the weight of the drill body 10 is required.

[0029] In one embodiment, the helical length of the reinforcing rib 12 is less than the helical length of the drill body 11, wherein the drill body 11 extends axially from the head to near the tail, and the reinforcing rib 12 covers the area of ​​greatest stress concentration in the drill body 10. Optionally, the length of the reinforcing rib 12 is 1 / 2 to 7 / 8 of the helical length of the drill body 11, which can both specifically improve the strength of key areas and avoid the decrease in chip removal performance caused by excessively long reinforcing ribs 12.

[0030] Specifically, the helical length of the reinforcing rib 12 is 1 / 2, 2 / 3, 3 / 4, 7 / 8, etc., of the helical length of the drill body 11. The reinforcing rib 12 is not provided at the end of the drill body 11, which can increase the end space of the drill body 11 and improve the smoothness of chip removal.

[0031] In one optional embodiment, the reinforcing rib 12 is a continuous convex rib structure; in another optional embodiment, the reinforcing rib 12 is a composite rib formed by combining multiple convex rib segments. There is a space between adjacent convex ribs at both ends.

[0032] like Figures 2 to 5As shown, furthermore, the cross-sectional dimension of the reinforcing rib 12 gradually decreases towards the cutting edge. The guide section 121 of the reinforcing rib 12 is designed with a refined structure, which can prevent the reinforcing rib 12 from forming an abrupt structural step at the head of the drill body 10, and prevent debris from accumulating at the step formed by the reinforcing rib 12, resulting in increased chip removal; at the same time, the gradually changing transition structure of the guide section 121 of the reinforcing rib 12 can reduce stress concentration and prevent cracks from appearing at the connection between the reinforcing rib 12 and the drill body 10 due to impact loads.

[0033] In one embodiment, there are two drill bodies 11, and each drill body 11 has a reinforcing rib 12 at the bottom of its groove. The two drill bodies 11 are symmetrically distributed along the circumference of the drill body 10. With the corresponding two reinforcing ribs 12, the stress distribution in the circumferential direction of the drill body 10 is more uniform, avoiding bending of the drill body 10 due to excessive stress on one side. At the same time, the double drill body 11 design can further improve chip removal efficiency and is suitable for drilling operations with high speed and large feed rate.

[0034] In one embodiment, the diameter of the drill body 10 is 5mm-10mm, and the length of the drill body 10 is greater than or equal to 600mm. Large-diameter hammer drill bits have high structural strength, and the reinforcing ribs 12 can be added according to design requirements. In this embodiment, for a drill body 10 with a diameter of 5mm-10mm, reinforcing ribs 12 are added inside the drill body 11 to compensate for the deficiency of insufficient strength caused by an excessively large slenderness ratio in a slender drill body 10.

[0035] The length of the drill body 10 is ≥600mm. The drill body 10 can meet the needs of deep holes in walls, deep holes in precast concrete components, etc. With the support of the reinforcing rib 12, the radial sway of the drill body 10 during the drilling process can be effectively reduced, the structural strength is increased, and thus the drilling accuracy is improved.

[0036] To further improve the service life of the drill bit, the drill body 11 and the reinforcing rib 12 are coated with a wear-resistant coating. The wear-resistant coating improves the wear resistance and surface hardness of the drill bit. For example, a tungsten carbide coating or a titanium nitride coating is preferably used. The wear-resistant coating significantly increases the surface hardness of the drill body 11 and the reinforcing rib 12, reduces wear from chips, lowers the coefficient of friction between chips and the surface, and improves chip removal smoothness.

[0037] like Figures 1 to 3As shown, in one embodiment, the drill body 10 has a fitting groove 13 at its head. The drill bit also includes a carbide cutting tip 20 embedded in the fitting groove 13. The carbide cutting tip 20 and the drill body 10 are welded and fixed together. The opening of the drill body 11 is located on one side of the carbide cutting tip 20. The head of the drill bit is machined using the carbide cutting tip 20. The hardness of the carbide cutting tip 20 is much higher than that of the drill body 10, which can improve the wear resistance and impact resistance of the cutting edge, making it suitable for drilling into high-hardness concrete. The fitting groove 13 and the welding method ensure the connection strength between the cutting tip and the drill body 10, preventing the cutting tip from falling off under high-frequency impact.

[0038] The opening of the drill body 11 is located on one side of the cutter head, which can directly guide the chips generated by the cutting edge into the drill body 11, reducing the accumulation of chips near the cutter head.

[0039] In one embodiment, the drill bit further includes a mounting portion 30 located at the top of the drill body 11. The diameter of the mounting portion 30 is larger than the diameter of the drill body 10. The surface of the mounting portion 30 is provided with recessed guide grooves 32 and at least two assembly grooves 31. The mounting portion 30 is used to connect the drill bit to the output shaft of the electric hammer, enabling quick assembly and disassembly. The increased diameter of the mounting portion 30 allows for a proper fit with the output shaft of the electric hammer, improving assembly consistency and increasing the strength of the drill bit.

[0040] The guide groove 32 enables quick positioning of the mounting part 30 and the output shaft, avoiding circumferential misalignment during assembly; multiple mounting grooves 31 are provided, which engage with the protrusions on the output shaft to transmit rotational torque and impact load, ensuring the stability of power transmission and preventing slippage.

[0041] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of this application and include common knowledge or customary technical means in the art that are not disclosed in this invention.

Claims

1. A reinforced electric hammer drill bit, the electric hammer drill bit comprising a drill body, the head of the drill body being provided with a cutting edge, and at least one chip removal groove extending along its axial direction on the drill body, characterized in that, The drill body also includes at least one reinforcing rib protruding from the bottom surface of the chip removal groove. The spiral curve of the reinforcing rib is the same as that of the chip removal groove, and the maximum width of the reinforcing rib is less than the width of the chip removal protrusion between the chip removal grooves.

2. The reinforced electric hammer drill bit according to claim 1, characterized in that, The ratio of the protrusion height of the reinforcing rib to the depth of the chip removal groove is B, where 0.5 ≤ B ≤ 1.

3. The reinforced electric hammer drill bit according to claim 1, characterized in that, The cross-sectional shape of the reinforcing rib is circular, trapezoidal, triangular, or rectangular.

4. The reinforced electric hammer drill bit according to claim 1, characterized in that, The spiral length of the reinforcing rib is less than the spiral length of the chip removal groove.

5. The reinforced electric hammer drill bit according to claim 4, characterized in that, The cross-sectional dimension of the reinforcing rib gradually decreases at the end facing the cutting edge.

6. The reinforced electric hammer drill bit according to claim 1, characterized in that, The number of chip removal grooves is two, and the bottom of each chip removal groove is provided with the reinforcing rib.

7. The reinforced electric hammer drill bit according to claim 1, characterized in that, The diameter of the drill body is 5mm-10mm, and the length of the drill body is greater than or equal to 600mm.

8. The reinforced electric hammer drill bit according to claim 1, characterized in that, The chip removal groove and reinforcing rib are coated with a wear-resistant coating.

9. The reinforced electric hammer drill bit according to claim 1, characterized in that, The head of the drill body is provided with a fitting groove, and the drill bit also includes a carbide cutting tip embedded in the fitting groove. The carbide cutting tip and the drill body are welded and fixed together, and the opening of the chip removal groove is located on one side of the carbide cutting tip.

10. The reinforced electric hammer drill bit according to claim 1, characterized in that, The drill bit also includes a mounting portion located at the top of the drill body. The diameter of the mounting portion is larger than the diameter of the drill body. The surface of the mounting portion is distributed with recessed guide grooves and at least two assembly grooves.

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