TWM626243U - Disposable central drill bit locking structure - Google Patents

Abstract

This creation is about the improvement of the locking structure of a disposable center drill, especially one that can increase the locking strength, thereby simplifying the structural design of the tool.

The disposable center drill locking structure of this creation includes a tool body and a center drill. The tool body of the tool body is provided with a tool holder, the tool holder is provided with at least two screw holes, and the two sides of the screw holes are provided with circular shapes and The positioning column is not a whole circle, and the tool holder can accommodate a flat center drill that is opposite to the tool holder. The center drill is provided with two corresponding fixing holes. The center drill is locked in the tool holder by bolts, and the two sides of the fixing hole of the center drill are provided with semicircular notch locating grooves, which are matched with the positioning posts of the tool holder.

Description

Disposable center drill locking structure

This work is about the improvement of the locking structure of a center drill, especially a center drill with a discarded structure design, which has a stable locking structure, and does not cause the vibration phenomenon of tool deflection due to torque when it is subjected to lateral resistance.

The conventional center drill is designed with a circular rod body, and the two ends are set as center drill bits. The material is made of high-speed steel (HSS). However, the cutting speed of high-speed steel is limited. The applicant in this case aims to improve processing efficiency and processing quality On the premise of reducing the processing time, the tool material of the center drill is changed to tungsten carbide, and its processing speed will be 5~20 times that of high-speed steel, and the tool body and center drill of a new type are redesigned. Please refer to The applicant in this case has previously applied for the National New Patent Publication No. M361393 "Center Drill Tool", and the aforementioned applicant's No. M361393 "Center Drill Tool" has a variety of progressive and innovative structural designs, which are well recognized by the tool market. And users like it, but it still needs to be improved in use. The diameter of the cutter body 20 is too large, so that the center drill is limited during drilling, such as the step-shaped workpiece in Figure 8 or the narrow deep groove in Figure 9. The internal drilling of the center hole is often impossible because the diameter of the cutter body 20 is too large.

In addition, the center drill 30 of the "center drill tool" No. M361393 is locked by a bolt 40. Please refer to Fig. 10. When the center drill 30 is used for the side chamfering of the workpiece, the center drill 30 has two cutting edges. will be subjected to an alternating side thrust F which produces a lateral thrust on the bolt 40 Thrust F and moment M, even if the center drill 30 is restricted by the positioning rod 23, there is still a small tolerance between the center drill 30 and the positioning rod 23, even if the tolerance value is controlled below 0.05mm, there will still be Small shaking and chamfering will even cause the center drill 30 to generate vibration in a small frequency range. The higher the rotational speed, the higher the vibration frequency, which will reduce the roughness value and dimensional accuracy of the workpiece surface.

It is known that the "center drill tool" No. M361393 is locked by a bolt. When the center drill is used for side chamfering of the workpiece, it will be subjected to alternating lateral thrusts, which will generate lateral thrusts and moments on the bolts, resulting in the The center drill produces the phenomenon of tool vibration in a small frequency range. The higher the rotation speed, the higher the vibration frequency, which leads to the disadvantage of reducing the surface roughness value and dimensional accuracy of the workpiece, and the diameter of the center drill body is too large, so that the center drill is in the drilling process. It is limited when drilling, especially in stepped workpieces or drilling center holes in narrow deep grooves, often because the diameter of the tool body is too large and cannot be machined.

The disposable center drill locking structure of this creation includes a tool body and a center drill. The tool body of the tool body is provided with a tool holder, the tool holder is provided with at least two screw holes, and the two sides of the screw holes are provided with circular shapes and The positioning column is not a whole circle, and the tool holder can accommodate a flat center drill that is opposite to the tool holder. The center drill is provided with two corresponding fixing holes. The center drill is locked in the tool holder by bolts, and the two sides of the fixing hole of the center drill are provided with semicircular notch locating grooves, which are matched with the positioning posts of the tool holder.

In this creation, two bolts are used to strengthen the locking strength of the center drill and the tool body. In addition to resisting the moment caused by the cutting force, avoiding the phenomenon of tool vibration caused by a single bolt can be simplified due to the increased locking strength. The straight edge structure on both sides of the tool holder, the tool The structure of the main body is simplified, and the diameter can be reduced by 40%, which will not hinder the machining of the center hole of stepped workpieces or workpieces with narrow grooves, thereby improving the processing performance.

1: Tool body

10: Knife handle

20: Blade

21: Knife holder

221: screw hole

23: Positioning rod

231: Positioning post

30: Center Drill

31: Fixing hole

32: Positioning slot

33: Straight edge

34: Drill blade

35: Tapered Edge

351: cutting groove

40: Bolts

41: Bolt Head

P: thrust

R Heli

F, F ₁ : Lateral thrust

M, M ₁ , M ₂ : Moment

Figure 1 is a three-dimensional system diagram of this creation

Figure 2 is a combination diagram of this creation

Figure 3 is a side view combined view of this creation

Figure 4 is a schematic diagram of the center drill locked in the tool holder to generate thrust force in this creation

Figure 5 is a schematic diagram of the center drilling and chamfering construction of this creation

Figure 6 is a schematic diagram of this work in the drilling of hierarchical workpieces

Fig. 7 is a schematic diagram of this work for drilling a workpiece with a narrow groove

Figure 8 is a schematic diagram of the "center drill tool" No. M361393 drilling a hierarchical workpiece

Figure 9 is a schematic diagram of the "center drill tool" No. M361393 drilling a workpiece with a narrow groove

Figure 10 is a schematic diagram of the chamfering construction of No. M361393 "Center Drill Tool"

The disposable center drill locking structure of the present creation, please refer to Figures 1 and 2, including a tool body 1 and a center drill 30; wherein: the tool body 1 includes a tool handle 10 and a tool body 20, the aforementioned handle 10 It can be set as a straight rod shape or a tapered rod shape; the knife body 20 is provided with a knife accommodating seat 21, and the knife accommodating seat 21 is provided with at least two screw holes 221, Both sides of the screw hole 221 are provided with circular and non-circular positioning posts 231, and the tool holder 21 can accommodate a flat center drill 30 in a shape opposite to the tool holder; The center drill 30 is a flat body. The center of the body is provided with two fixing holes 31. The two sides of the fixing holes 31 are provided with positioning grooves 32 with semicircular grooves. The two sides of the center drill 30 ( The upper and lower sides of the positioning groove 32 are set as the straight edge 33, the end of the center drill 30 is set as the drill edge 34, and the taper edge 35 is set between the drill edge 34 and the straight edge 33. Having a cutting edge with a cutting groove 351 , the center drill 30 is locked to the tool holder 21 by two bolts 40 .

Please refer to FIG. 3 , in the present invention, the body of the center drill 30 is provided with two fixing holes 31 , and the center position of the two fixing holes 31 and the center position of the two screw holes 221 of the tool holder 21 have a slight deviation The value of the offset distance e is about 0.15mm; as shown in FIG. 2, when the center drill 30 is inserted into the tool body 1, the positioning grooves 32 on both sides of the center drill 30 and the tool body 1 The positioning posts 231 are fitted together and locked by two bolts 40 , as shown in FIGS. 2 and 3 , since the center of the two fixing holes 31 and the center of the two screw holes 221 of the tool holder 21 have a small With the offset distance e, when the two bolts 40 are locked downward, the bolt heads 41 (as shown in FIG. 1 ) will push the thrust P (as shown in FIG. 3 ) that pushes the fixing holes 31 upward and downward. The positioning grooves 32 on both sides of the center drill 30 and the positioning column 231 produce a resultant force R that closely fits together, as shown in FIG. The positioning groove 32 of the center drill 30 and the positioning column 231 of the tool holder 21 generate a pressing thrust P and a resultant force R. Accordingly, the center drill 30 is locked in the tool holder 21 by the bolt 40, and at the same time the upper The degrees of freedom of , down direction, and left and right directions are all restricted.

In addition, by the arrangement of the two bolts 40, the moment caused by the cutting force can be resisted, and the phenomenon of tool vibration caused by a single bolt 40 can be avoided. As shown in FIG. 5, when the two bolts 40 are cutting (especially It is in the chamfering cutting of the workpiece) the two cutting edges alternately bear the lateral thrust F, the two bolts 40 bear the lateral thrust F ₁ on average (one bolt 40 bears half of the lateral thrust F) and the lateral thrust F against the torques M ₁ and M ₂ generated by the bolts 40 , the two bolts 40 are opposed to each other to prevent the center drill 30 from shaking, and the positioning grooves 32 on both sides of the center drill 30 are matched with the positioning posts 231 of the tool body 1 . , which makes the locking force of the two bolts 40 to lock the center drill 30 tighter. Therefore, compared with the structure of the applicant's No. M361393 "center drill tool", the structure of the straight edges on both sides of the tool holder 21 is simplified. The structure of the tool body 1 is simplified, and the diameter can be reduced by at least 40%, so that the center drill 30 will not hinder the machining of the center hole of the stepped workpiece in FIG. 6 or the workpiece with the narrow groove in FIG. 7 .

In this creation, two bolts are used to strengthen the locking strength of the center drill and the tool body. In addition to resisting the moment caused by the cutting force, avoiding the vibration of the tool caused by a single bolt can also simplify the installation due to the increased locking strength. The straight edge structure on both sides of the tool seat, the structure of the tool body is simplified, and the diameter can be reduced by 40%, which will not hinder the machining of the center hole of the stepped workpiece or the workpiece with narrow grooves, thereby improving the cutting capacity. It is very progressive and practical, and it is in line with the application requirements for a new type of patent under the Patent Law, and it is due to file an application in accordance with the law.

This creation has progress and practicability among similar products, and through implementation and testing, it has been proved that this creation has industrial applicability, and this creation has not been found in publications or publicly used before the application. Therefore, this The patent requirements of progress, novelty and industrial applicability have been met at the time of creation, and an application is filed in accordance with the law; however, the above is only a preferred feasible embodiment of this creation, which does not limit the scope of the patent of this creation. Equivalent structural changes made by using the contents of this creation manual and illustrations are all included in the scope of this creation.

1: Tool body

10: Knife handle

20: Blade

21: Knife holder

221: screw hole

231: Positioning post

30: Center Drill

31: Fixing hole

32: Positioning slot

33: Straight edge

34 drill: blade

35: Tapered Edge

351: cutting groove

40: Bolts

41: Bolt Head

Claims (1)

A discarded center drill locking structure includes a tool body and a center drill; wherein: the tool body includes a tool handle and a tool body, the tool body is provided with a tool holder, and the tool holder is provided with at least two screw holes, The two sides of the screw hole are provided with circular and non-circular positioning posts, and the tool holder can accommodate a flat center drill that is opposite to the tool holder; the center drill is a A flat body, the center of the body is provided with two fixing holes, the two sides of the fixing holes are provided with positioning grooves with semi-circular grooves, the end of the center drill is set as a drill edge, and the center drill is locked by two bolts Secured to the knife holder.

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