Roll forming chip groove electric hammer drill bit

Abstract

The utility model relates to an electric hammer drill bit for a rolling forming chip groove, which not only can reduce the use of raw materials, but also is high in drill bit strength, high in processing efficiency and stable in quality, and comprises an electric hammer drill bit body, four spiral chip grooves are formed in a rod body of a drill rod in the electric hammer drill bit body in a rolling mode, and the diameter of the drill rod section where the spiral chip grooves are located is increased through rolling to form a thickened section. Chip removal inlets of the four spiral chip removal grooves are distributed in the outer circle face of the drill rod at equal intervals and penetrate through the outer end face of the drill rod, and chip removal outlets of the four spiral chip removal grooves are formed in a rod body of the drill rod. The electric hammer drill bit has the advantages that the use of raw materials can be reduced, the drill bit strength is high, the machining efficiency is high, and the quality is stable.

Description

Technical Field

[0001] The utility model belongs to the field of electric hammer drill manufacturing, in particular to an electric hammer drill with a rolling-formed chip removal groove. Background Art

[0002] The chip grooves of the existing electric hammer drill bits are formed by turning, such as the prior patent CN 203853966 U, named "A kind of electric hammer drill bit" owned by the holding subsidiary (Hangzhou Lichang Tools Co., Ltd.) of the applicant's holding parent company (Hangzhou Jinzuan Tools Co., Ltd.), which includes a shank with a cutter head embedded at the tip and a shank handle. The shank and the shank handle are an integral structure, and the surface of the shank is provided with two spiral chip grooves that are radially opposite to each other. The groove depth of the spiral chip groove gradually becomes shallower from 3 cm before the outlet end to the outlet end. There is no trace of the tool retreat step and no sharp angle at the outlet end of the spiral chip groove; the angle between the blade of the spiral chip groove and the axial centerline of the drill bit is an obtuse angle. The spiral chip groove is a semicircular spiral chip groove, and the angle between the blade of the semicircular spiral chip groove and the axial centerline of the drill bit is 145±10°. The spiral chip groove is a flat-bottomed trapezoidal spiral chip groove, and the angle between the blade of the flat-bottomed trapezoidal spiral chip groove and the axial centerline of the drill bit is 135±10°. The tool bar handle is a square handle, and a key groove is opened on each surface of the square handle. Since the chip groove of this type of electric hammer drill is formed by turning, in order to ensure the strength of the tool bar section with the spiral chip groove, the diameter of the tool bar needs to reach a certain size (for example, if the length of the electric hammer drill is 160mm and the depth of the spiral chip groove is 2mm, the diameter of the tool bar section where the spiral chip groove is located needs to reach 8mm), which requires more raw materials to produce this type of electric hammer drill, thereby increasing its production cost. Utility Model Content

[0003] Design purpose: In order to avoid the shortcomings of the background technology, a rolling-formed chip groove electric hammer drill is designed that can not only reduce the use of raw materials, but also has high drill bit strength, high processing efficiency and stable quality.

[0004] Design plan: To achieve the above design objectives.

[0005] 1. The drill rod in the electric hammer drill body is roll-formed with four spiral chip grooves, and the diameter of the drill rod section where the spiral chip grooves are located is enlarged by rolling to form a thickened section. The chip removal inlets of the four spiral chip grooves are equidistantly arranged on the outer circumferential surface of the drill rod, and the chip removal inlets of the four spiral chip grooves pass through the outer end surface of the drill rod. The design of the chip removal outlets of the four spiral chip grooves on the drill rod body is one of the technical features of the utility model. The purpose of such design is that: four spiral chip grooves are roll-formed on the rod body of the drill rod in the electric hammer drill bit body, and the diameter of the drill rod section where the spiral chip grooves are located is enlarged by rolling to form a thickened section, the chip removal inlets of the four spiral chip grooves are equidistantly arranged on the outer circumferential surface of the drill rod, and the chip removal inlets of the four spiral chip grooves pass through the outer end surface of the drill rod, and the rod body of the drill rod is provided with four chip removal outlets of the spiral chip grooves; the spiral chip grooves in the electric hammer drill bit are roll-formed by a chip groove rolling device after the electric hammer drill bit blank is annealed, which not only has high processing efficiency, but also the drill rod section (thickened section) where the spiral chip grooves are located is enlarged by rolling, which improves the utilization rate of raw materials while ensuring the strength of the drill bit, that is, it reduces the production cost of the electric hammer drill bit while ensuring stable production quality.

[0006] 2. The outer end surface of the drill rod is provided with an annular protrusion formed by extrusion around it, and a cutter head seat mounting groove is formed between the inner wall surface of the annular protrusion and the outer end surface of the drill rod, which is the second technical feature of the utility model. The purpose of this design is that: the rod body of the drill rod in the electric hammer drill body is roll-formed with four spiral chip removal grooves, and the chip removal entrances of the four spiral chip removal grooves are equidistantly arranged on the outer circumferential surface of the drill rod, and the outer end surface of the drill rod is provided with an annular protrusion formed by extrusion around it, and a cutter head seat mounting groove is formed between the inner wall surface of the annular protrusion and the outer end surface of the drill rod. The formation of the cutter head seat mounting groove facilitates the subsequent welding of the cutter head seat, and the chip removal entrances of the four spiral chip removal grooves are equidistantly arranged on the outer circumferential surface of the drill rod, which is conducive to the production of the cutter head seat mounting groove. In addition, the arrangement and distribution of the four spiral chip removal grooves can also ensure the roundness of the drill rod section where the spiral chip removal groove is located after rolling (good roundness can improve the use effect and service life of the drill rod section).

[0007] 3. A truncated cone-shaped transition section is provided between the drill rod and the drill handle, and the drill rod, the drill handle and the truncated cone-shaped transition section are an integral structure, the narrow circle diameter in the truncated cone-shaped transition section matches the diameter of the drill rod, and the wide circle diameter in the truncated cone-shaped transition section matches the diameter of the drill handle, which is the third technical feature of the utility model. The purpose of such a design is that a truncated cone-shaped transition section is provided between the drill rod and the drill handle, and the drill rod, the drill handle and the truncated cone-shaped transition section are an integral structure, the narrow circle diameter in the truncated cone-shaped transition section matches the diameter of the drill rod, and the wide circle diameter in the truncated cone-shaped transition section matches the diameter of the drill handle, and the setting of the truncated cone-shaped transition section can prevent the sharp part between the drill rod and the drill handle from injuring people or objects.

[0008] 4. The design of multiple keyways on the outer circumference of the drill shank is the fourth technical feature of the utility model. The purpose of this design is that the outer circumference of the drill shank is provided with multiple keyways, and the arrangement of the keyways facilitates the assembly of a rolling-formed chip removal groove electric hammer drill bit and an electric hammer.

[0009] Technical solution: A roll-formed chip groove electric hammer drill, comprising an electric hammer drill body, wherein the drill rod in the electric hammer drill body is roll-formed with four spiral chip grooves, and the diameter of the drill rod section where the spiral chip grooves are located is enlarged by rolling to form a thickened section, the chip removal inlets of the four spiral chip grooves are equidistantly arranged on the outer circumferential surface of the drill rod and the chip removal inlets of the four spiral chip grooves pass through the outer end surface of the drill rod, and the drill rod body is provided with four chip removal outlets of the spiral chip grooves.

[0010] Compared with the background technology, the electric hammer drill bit with rolling-formed chip grooves can not only reduce the use of raw materials, but also has high drill strength, high processing efficiency and stable quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 The present invention is a three-dimensional structural schematic diagram of an electric hammer drill bit with a rolling-formed chip groove.

[0012] Figure 2 The diagram is a schematic diagram of the structure of an electric hammer drill bit with a rolling-formed chip groove, viewed from above. DETAILED DESCRIPTION

[0013] Embodiment 1: refer to the attached Figure 1-Figure 2 A roll-formed chip groove electric hammer drill, comprising an electric hammer drill body 1, wherein the drill rod 2 in the electric hammer drill body 1 is roll-formed with four spiral chip grooves 21, and the diameter of the drill rod section where the spiral chip grooves 21 are located is enlarged by rolling to form a thickened section 22, wherein the four spiral chip grooves 21 are formed at one time by a chip groove rolling device, and the chip groove rolling device is a prior art, so it is not described here in detail, the chip removal inlets 23 of the four spiral chip grooves 21 are equidistantly arranged on the outer circumferential surface of the drill rod, and the chip removal inlets 23 of the four spiral chip grooves 21 pass through the outer end surface of the drill rod 2, and the rod body of the drill rod 2 is provided with four chip removal outlets 24 of the spiral chip grooves 21. The outer end surface of the drill rod 2 is provided with an annular protrusion 25 formed by extrusion and trimming, and a cutter head seat mounting groove 26 is formed between the inner wall surface of the annular protrusion 25 and the outer end surface of the drill rod 2.

[0014] The cross section of the spiral chip groove 21 is an arc surface, the groove width of the spiral chip groove 21 is 3.8mm-4.2mm, the groove depth of the spiral chip groove 21 is 1.8mm-2.2mm, the thickness of the groove wall between adjacent spiral chip grooves 21 is 0.9mm-1.1mm, the diameter of the drill rod 2 is 5.7mm-6.3mm, the diameter of the thickening section 22 is 7.7mm-8.3mm, and the length of the electric hammer drill body 1 is 150mm-170mm. Preferably, the groove width of the spiral chip groove 21 is 4mm, the groove depth of the spiral chip groove 21 is 2mm, the thickness of the groove wall between adjacent spiral chip grooves 21 is 1mm, the diameter of the drill rod 2 is 6mm, the diameter of the thickening section 22 is 8mm, and the length of the electric hammer drill body 1 is 160mm. Preferably, the length of the thickened section 22 is 70 mm, the length of the drill shank is 55 mm and the diameter of the drill shank is 10 mm, and the depth of the tool head seat mounting groove 26 is 2 mm.

[0015] A truncated cone-shaped transition section 4 is provided between the drill rod 2 and the drill shank 3, and the drill rod 2, the drill shank 3 and the truncated cone-shaped transition section 4 form an integral structure. The narrow circle diameter in the truncated cone-shaped transition section 4 matches the diameter of the drill rod 2, and the wide circle diameter in the truncated cone-shaped transition section 4 matches the diameter of the drill shank 3.

[0016] A plurality of key grooves 31 are arranged on the outer circumferential surface of the drill shank 3 .

[0017] It should be understood that although the above embodiments provide a relatively detailed textual description of the design concept of the present utility model, these textual descriptions are only simple textual descriptions of the design concept of the present utility model, rather than limitations on the design concept of the present utility model. Any combination, addition or modification that does not exceed the design concept of the present utility model shall fall within the protection scope of the present utility model.

Claims

1. A rolling-formed chip removal groove electric hammer drill, comprising an electric hammer drill body (1), characterized in that: The drill rod (2) in the electric hammer drill bit body (1) is roll-formed with four spiral chip removal grooves (21) on its rod body, and the diameter of the drill rod section where the spiral chip removal grooves (21) are located is enlarged by rolling to form a thickened section (22), the chip removal inlets (23) of the four spiral chip removal grooves (21) are equidistantly arranged on the outer circumferential surface of the drill rod, and the chip removal inlets (23) of the four spiral chip removal grooves (21) pass through the outer end surface of the drill rod (2), and the drill rod (2) is provided with four chip removal outlets (24) of the spiral chip removal grooves (21) on its rod body.

2. The rolling-formed chip groove electric hammer drill according to claim 1, characterized in that: An annular protrusion (25) formed by extrusion is provided around the outer end surface of the drill rod (2), and a cutter head seat mounting groove (26) is formed between the inner wall surface of the annular protrusion (25) and the outer end surface of the drill rod (2).

3. The rolling-formed chip removal groove electric hammer drill according to claim 1, characterized in that: The cross section of the spiral chip groove (21) is an arc-shaped surface, the groove width of the spiral chip groove (21) is 3.8 mm-4.2 mm, the groove depth of the spiral chip groove (21) is 1.8 mm-2.2 mm, the thickness of the groove wall between adjacent spiral chip grooves (21) is 0.9 mm-1.1 mm, the diameter of the drill rod (2) is 5.7 mm-6.3 mm, the diameter of the thickened section (22) is 7.7 mm-8.3 mm, and the length of the electric hammer drill body (1) is 150 mm-170 mm.

4. The rolling-formed chip removal groove electric hammer drill according to claim 3 is characterized in that: The groove width of the spiral chip groove (21) is 4 mm and the groove depth of the spiral chip groove (21) is 2 mm, the thickness of the groove wall between adjacent spiral chip grooves (21) is 1 mm, the diameter of the drill rod (2) is 6 mm, the diameter of the thickened section (22) is 8 mm, and the length of the electric hammer drill body (1) is 160 mm.

5. The rolling-formed chip groove electric hammer drill according to claim 1, characterized in that: A truncated cone-shaped transition section (4) is provided between the drill rod (2) and the drill shank (3), and the drill rod (2), the drill shank (3) and the truncated cone-shaped transition section (4) form an integral structure; the narrow circle diameter in the truncated cone-shaped transition section (4) matches the diameter of the drill rod (2), and the wide circle diameter in the truncated cone-shaped transition section (4) matches the diameter of the drill shank (3).

6. The rolling-formed chip groove electric hammer drill according to claim 5, characterized in that: A plurality of key grooves (31) are provided on the outer circumferential surface of the drill shank (3).

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