JP3156158U - Strong twist corner rounding cutter - Google Patents

Abstract

An object of the present invention is to provide a strong torsion corner rounding cutter having excellent durability capable of smoothly and rapidly machining an R chamfered cut surface. A strongly twisted corner rounding cutter having a chamfered portion having a radius R at a corner of a work material, having 2 to 4 outer peripheral blades, having a groove groove twist angle of 30 to 60? The radius R with respect to the shank diameter is about 30 to 37% in the case of two blades, about 25 to 33% in the case of three blades, and about 20 to 25% in the case of four blades. And [Selection] Figure 1

Description

  The present invention relates to a strong twist corner rounding cutter for chamfering an R shape on a work material, and has an original strong twist shape for the purpose of improving cutting ability and durability and providing a smooth cutting surface. The present invention relates to a strong twist corner rounding cutter having a blade groove.

  The corner rounding cutter is a cutting tool having an R-shaped outer peripheral blade, which is intended to cut a work material by itself rotating and moving and to provide an R-shaped cutting surface on the work material. . As the outer peripheral blade of the end mill including the corner rounding cutter, there are a twist blade type having a twist angle and a straight blade type having no twist angle. The twisted blade type is superior to the straight blade type in cutting ability (high-speed machining), durability, and discharge of work piece chips, and is known to have the effect of giving a smooth cutting surface to the work material. It has been.

A conventional corner rounding cutter is a straight-blade type with no twist angle due to restrictions in manufacturing technology, and a rake face of the blade groove is a flat surface (Non-Patent Document 1).
Catalog issued by Sanko Seisakusho Co., Ltd. on October 10, 2007 "FA Coated Carbide / Corner Lounge Cutter (3-Flute)" catalog

  The conventional corner rounding cutter shown in Non-Patent Document 1 has high cutting resistance between the corner of the work material and the outer peripheral edge, so the outer peripheral edge wears quickly, and tool traces tend to remain on the cutting surface, making high-speed machining difficult. It is. In general, R chamfering with a radius of R2 mm or more requires two steps of pre-processing and finishing. Moreover, since the straight blade is inferior in the discharge capability of the work material chips, there is also an adverse effect on the cut finish surface due to the work material chips.

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a durable and highly torsional corner rounding cutter capable of smoothly and rapidly machining an R chamfered cut surface. It is in.

  The outer peripheral blade of the two-blade strongly twisted corner rounding cutter according to claim 1 of the present invention is a two-blade arranged at equal intervals, the twist angle of the blade groove is 30 ° to 60 °, and the shank diameter This is a strong twist corner rounding cutter characterized in that the radius R is 30% to 37%.

  The outer peripheral blade of the three-blade strongly twisted corner rounding cutter according to claim 1 of the present invention is a three-blade arranged at equal intervals, the twist angle of the blade groove is 30 ° to 60 °, and the shank diameter This is a strongly twisted corner rounding cutter characterized in that the size of the radius R with respect to is 25% to 33%.

  The outer peripheral blade of the four-blade strongly twisted corner rounding cutter according to claim 1 of the present invention is a four-blade arranged at equal intervals, the twist angle of the blade groove is 30 ° to 60 °, and the shank diameter This is a strongly twisted corner rounding cutter characterized in that the size of the radius R is 20% to 25%.

  The present invention is a cutting tool in which a twist angle is applied to a blade groove. Each blade portion of the outer peripheral blade sequentially moves while point-contacting the work material from the tip to the end on the shank side, and R machining finish is performed. At that time, it is desirable to match the torsion angle of the blade groove with the material of the work material, processing conditions, etc. so as not to place an excessive burden on each blade part, but since the conventional corner rounding cutter is a straight blade type, It is impossible to change the shape of the blade groove in accordance with the material of the work material, processing conditions, and the like. Since the outer peripheral blade is burdened when the twist angle of the blade groove is too small or too large, the present invention specifies the twist angle of the blade groove in the range of 30 ° to 60 °.

  Also, the radius R relative to the shank diameter of the two-blade strong twist corner rounding cutter is 30% to 37%, and the radius R relative to the shank diameter of the three-blade strong twist corner rounding cutter is 25% to The reason why the radius R is 20% to 25% with respect to the shank diameter of the four-blade strong twist corner rounding cutter at 33% is based on any technical viewpoint.

  According to the strongly twisted corner rounding cutter of the present invention, by applying a strong torsion angle to the blade groove, which was impossible in the past due to manufacturing restrictions, the cutting resistance is greatly reduced and the durability is improved and high speed machining is possible. It is possible to efficiently discharge the work material chips and finish the cutting surface much more smoothly. In general, even in R chamfering with a radius larger than R2 mm, which requires two steps of pre-processing and finishing, the effect is exhibited without any need for pre-processing.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 4, taking as an example a case where three outer peripheral blades of a strongly twisted corner rounding cutter (R = 5 mm) are formed at equal intervals with a shank diameter of 16 mm. I will explain.
1 and 2 are perspective views of the strongly twisted corner rounding cutter 1. FIG. 3 is a plan view thereof, and FIG. 4 is a side view thereof. 5A, 5B, and 5C show a process of providing an R chamfer on a work material by using a strongly twisted corner rounding cutter 1, respectively.

  A strongly twisted corner rounding cutter 1 according to an embodiment of the present invention includes a blade groove 3 spirally twisted at an angle of 40 ° from the tip surface 2 toward the outer periphery of the shank as shown in FIG. The outer peripheral blade 4 is formed with a radius R5 mm shape with a shank diameter ratio of about 31% in the tool axis direction from the front end surface 2 toward the outer periphery of the shank.

  The corner rounding cutter is used for processing an angular corner of a work material into an R shape. For this reason, the most load is applied to the center of the R shape of the outer peripheral blade. Since the conventional corner rounding cutter is a straight blade, the outer peripheral blade first comes into contact with the work material near the center of the R shape to which the load is most applied. Due to this so-called adverse effect per point, the conventional corner rounding cutter has a significant problem in durability.

  Since the outer peripheral edge 4 of the highly twisted corner rounding cutter according to the embodiment of the present invention is a twisted blade type cutting tool formed on the blade groove 3 having a strong twist angle of 40 °, it is in contact with the work material. The point always moves in the same direction from the tip side A to the shank side B. By this operation, it is possible to avoid the point hit which is the biggest problem of the conventional corner rounding cutter. Accordingly, the cutting resistance is remarkably reduced, the durability of the outer peripheral cutting edge is remarkably improved, and the cutting surface can be finished remarkably smoothly. In addition, the twisted fluted rake face efficiently discharges workpiece chips, dramatically reducing the adverse effects of the workpiece chips on the finished cutting surface and making it possible to finish the cutting surface smoothly. It was.

Next, a process in which the contact point between the strongly twisted corner rounding cutter and the work material of the embodiment of the present invention always moves in the same direction from the tip side to the shank side will be described with reference to FIGS. explain.
FIG. 5A shows a state in which the strongly twisted corner rounding cutter rotates clockwise as indicated by an arrow, and the tip point A on the outer peripheral blade 4 starts to contact the work material W. FIG. FIG. 5B shows a state where the strongly twisted corner rounding cutter is further rotated and positioned in the middle of the same outer peripheral blade 4. This is the position of a small circle indicated by the arrow on the right side of FIG. FIG. 5 (c) shows a state in which the workpiece is further rotated and located at the end point B of the same outer peripheral blade 4, and the right figure shows that the angular corner of the work material W is rounded.

The perspective view of a strong twist corner rounding cutter. The perspective view which shows the front-end | tip vicinity of a strong twist corner rounding cutter. The top view which shows the front-end | tip of a strong twist corner rounding cutter. Side view of a strong twist corner rounding cutter. (A)-(c) is explanatory drawing which shows the state which finishes the corner of a work material into the radius R shape with a strong torsion corner rounding cutter.

  Compared with the conventional corner rounding cutter, the present invention not only dramatically improves the quality of the cutting surface, but also significantly shortens the conventional machining time and dramatically improves the durability. It is a cutting tool suitable for all the processes in which a conventional corner rounding cutter has been used, and has a great industrial applicability.

DESCRIPTION OF SYMBOLS 1 Shank 2 Tip surface 3 Flute 4 Outer peripheral blade 5 Outer peripheral flank A End point B on outer peripheral blade End point W on outer peripheral blade Work material

Claims (1)

A strongly twisted corner rounding cutter with a chamfered portion of radius R at the corner of the work material, having 2 to 4 outer peripheral blades, a groove groove twist angle of 30 ° to 60 °, and a radius with respect to the shank diameter Strong torsion, characterized in that the size of R is around 30-37% in the case of 2 blades, around 25-33% in the case of 3 blades, and 20-25% in the case of 4 blades Corner rounding cutter.

Images