JP-7856868-B1 - milling machine

JP7856868B1JP 7856868 B1JP7856868 B1JP 7856868B1JP-7856868-B1

Abstract

The challenge to be addressed is to provide a milling cutter that allows for inexpensive and easy replacement of the inserts. The blade portion 10 has a plurality of chips 12 with a bottom blade 121 and an outer peripheral blade 122, and a blade body portion 11 which is a plate-like body on which the plurality of chips 12 are fixed to the outer circumference, and grooves 113 are formed to match the positions of the chips 12. The tip portion 21 has a tip surface to which the rear end surface of the blade body portion 11 can be fixed in close contact and detachably, and a tip outer circumference portion which has an outer diameter of 100/100 to 92/100 based on the outer diameter of the blade portion 10, and a body side groove 211 is formed which is connected to the groove 113 of the blade body portion 11 that is in close contact with the body body portion 11, and the body 20 is rotatable around the axis of rotation. A blade portion mounting hole 11a is formed in the center of the blade body portion 11, and a body mounting hole/hole is formed in the center of the tip portion 21, and radial positioning is possible by inserting fastening bolts into which the outer circumference surface of the shaft portion is in close contact with the inner circumference surface of the respective mounting hole.

Inventors

成田大興
奥山裕平

Assignees

兼房株式会社

Dates

Publication Date: 20260511
Application Date: 20250901
Priority Date: 20240903

Claims (4)

A blade portion having multiple chips and a blade body portion which is a plate-like body having blade mounting holes that penetrate in the thickness direction and are fixed to the outer circumference of the multiple chips, The rear end surface of the blade body is provided with a tip surface that can be fixed in close contact and detachably, and the tip portion has a body mounting hole/hole opening in the center of the tip surface, and the outer diameter is 100/100 to 92/100 with the outer diameter of the blade portion as the reference (100/100), and the body is rotatable around the axis of rotation, A fastening bolt in which at least a portion of the outer circumferential surface of the shaft portion between the head and the threaded portion is inserted into the inner circumferential surface of the blade mounting hole and the body mounting hole/hole, and when fastened, the outer circumferential surface of the shaft portion is shaped to be in close contact with the inner circumferential surface of the blade mounting hole and the body mounting hole/hole, It has, The aforementioned rear end surface and the aforementioned front end surface are flat and in close contact over their entire surface. A pin-like projection member is attached to one of the front end surface and the rear end surface, and the other front end surface and the rear end surface have a rotation-preventing hole of a size into which the projection member can be inserted. The thickness of the blade body is 4 mm or more. The fastening bolt is a countersunk bolt, and a tapered seat corresponding to the head of the fastening bolt is formed in the tip-side portion of the blade mounting hole, which widens in diameter towards the tip. The pressing portion of the fastening bolt, which is the part that presses against the blade body, is substantially circular, and the outer diameter of the pressing portion is 40% or more and 90% or less of the outer diameter of the blade. Milling machine.
A groove is formed on the outer circumference of the blade body portion, corresponding to the position of the tip. A body side groove is formed on the outer circumference of the tip portion, which connects to the groove when the blade body portion is in close contact with it. The milling cutter according to claim 1.
The milling cutter according to claim 1 or 2, wherein the body has a cutting fluid supply passage formed connecting a cutting fluid supply port opening at the rear end and a cutting fluid injection port opening at the front end.
The blade mounting hole and the body mounting hole/hole are cylindrical in shape and have the same or different diameters. The outer circumferential surface of the shaft portion of the fastening bolt is such that the blade body portion is fastened to the tip portion. The milling cutter according to claim 1 or 2, which is inserted with a clearance between the entire inner surface of the blade mounting hole and the inner surface of the body mounting hole/hole, respectively, to achieve the required assembly accuracy.

Description

This invention relates to a milling machine. Milling cutters have tips made of cemented carbide, polycrystalline diamond, cubic boron nitride (CBN), or other ceramics attached to the outer circumference of a disc or cylinder. Among these, there are milling cutters in which replaceable cutting edges, each with a tip fixed to the outer circumference of a disc, are detachably fixed to the front of the body. Conventional insert-type milling cutters have multiple interchangeable blades, and each blade is attached to the body, making blade replacement cumbersome. In particular, when the diameter of the blade is small, there is a limit to the number of interchangeable blades that can be installed. Furthermore, in conventional interchangeable-head milling cutters (Patent Document 2), the interchangeable blades, which have multiple cutting edges, are provided with an spigot shaft and a threaded portion, and the body is provided with an spigot hole to fasten and align the interchangeable blades with the body. However, due to the complex structure, it has been difficult to manufacture the interchangeable blades at a low cost. In addition, other conventional milling machines (Patent Documents 1 and 3) fasten and align the replaceable blade and the body by providing a spigot hole in the replaceable blade and a spigot shaft in the body, but miniaturization was difficult due to interference in the fastening structure. WO2021/060271A1Japanese Patent Publication No. 2011-056594Japanese Patent Publication No. 2001-162430 This is a perspective view of the milling machine according to Embodiment 1.This is a plan view of the milling machine of Embodiment 1.This is a front view of the milling machine according to Embodiment 1.This is an exploded assembly drawing of the milling machine according to Embodiment 1.This is a cross-sectional view taken along line A-A in Figure 2.This is a perspective view of the milling machine of Embodiment 2.This is an exploded assembly drawing of the milling machine according to Embodiment 2.This is a cross-sectional view of Embodiment 2. The milling cutter of the present invention will be described in detail below based on embodiments with reference to the drawings. The milling cutter of this embodiment is a multi-blade milling cutter with an increased number of blades, and is particularly suitable for face milling. It is especially preferable to use it for processing light metals. In this specification, the direction toward the workpiece in the rotation axis direction of the milling cutter is referred to as the tip direction, and the opposite direction to the tip direction is referred to as the rear end direction. Due to problems when creating drawings from 3D models, lines that do not clearly appear on the surface of the actual product may appear in the drawings in areas where the curvature of the curved surface changes (for example, grooves 113 and body side grooves 211 in Figures 1, 3, and 4, and areas corresponding to grooves and body side grooves in Figures 6 and 7). Furthermore, the numerical range "x to y" described herein includes the lower limit x and the upper limit y. New numerical ranges can be constructed by arbitrarily combining these upper and lower limits, as well as the numerical values listed in the specification or examples. The new numerical range may also exclude one or both of the upper and lower limits. For example, a range greater than x or a range less than y can be adopted. Moreover, numerical values arbitrarily selected from any of the above numerical ranges can be used as the upper and lower limits of the new numerical range. The milling cutter of this embodiment has a cutting edge, a body, and fastening bolts. The cutting edge and the body are fixed together such that the rear end surface of the blade body constituting the cutting edge is in close contact with the front end surface of the body. The two are fixed together by fastening bolts. The rotation axis of the fastening bolts is arranged to coincide with the rotation axis of the cutting edge and the body. The blade section has multiple tips and a blade body to which these tips are fixed. The tips have a bottom edge and an outer edge that are sharpened. The material that makes up the tips is not particularly limited, but examples include cemented carbide, polycrystalline diamond, CBN, and other ceramics. In particular, the material can be changed between the cutting edge and the rest of the blade. The number of tips is not particularly limited. If the tip becomes worn or damaged, the blade can be removed from the body and replaced with a usable blade to continue using the tool. Replacing the blade is easier than replacing or adjusting the tip. The removed blade can be resharpened, repaired, or replaced to restore the tip. The blade body is generally plate-shaped and has an overall shape close to a disc. The material used to form the blade body is not particularly limited, but alloy tool steel is preferred. The thi