JPS614619A - Rotary cutting tool - Google Patents

Abstract

PURPOSE:To facilitate machining work by a blade further improve its rigidity, stability and accuracy, in the case of a cutting tool which fixes the blade having a cutting edge tip to the peripheral surface of a cylindrical main unit. CONSTITUTION:The main unit 1 forms on its peripheral cylindrical surface 3 a spiral stripe, having its both side surfaces vertical with respect to the axial core, to be cut, and this stripe is divided into sections, forming many protrusions 4. A blade 2 is formed in each unit of a cutting edge 20 of a tip C, and the protrusion 4 in the main unit 1 is engaged with a groove of the blade. A clamper 9, being placed between front and rear ends of the neighboring blades, fixes the blade by tightening a screw. The blade provides a stable condition for cutting torque because the clamper tightens one blade from its both ends.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rotary cutting tool having a blade having a cutting tip fixed to the outer peripheral surface of a cylindrical body.

(Prior art) Rotary cutting tools have changed from the conventional high-speed steel integral parts to the assembled indexable type with the development of cemented carbide. Even if it is a one-piece product, the cutting blade rotates one row at a time, so machining the chip seat where the indexable insert is attached can be done relatively easily on the side, but it is extremely difficult in the direction of the rake face due to the relationship between adjacent cutting edges. . There are also cartridge and locator methods, but installation is often limited by location, so it is more economical and performance-friendly to assemble the blade and main body in terms of materials and processing time. There are many things.

When cutting is performed in three rows, pressure motion, or threaded, it becomes even more difficult to grind the cutting edge or machine the chip seat in one piece. In particular, since it is essential for a hob, which is a gear-generating gear cutting tool, that the cutting edges be arranged in a threaded manner, there are very few inventions related to indexable hobs.

However, this type of invention disclosed in Japanese Patent Application Laid-open No. 57-102722 discloses that in order to arrange the cutting edges in a threaded manner, one unit is a blade corresponding to four teeth of a hob. The blade is inserted into a spiral guide groove provided on the main body, or a spiral strip is provided on the outer circumferential surface of the main body, and a similar guide groove is drilled on the bottom of the blade. 4- It is characterized by a pitch shift. However, there are problems as shown in (1) to (2) below.

■The spiral grooves and protruding strips provided on the main body can be machined with high precision as they are similar to the process of square screws, but the fitting part of the blade that fits into the blade is extremely difficult to machine. Hobs generally have about 12 teeth in the circumferential direction, so the range of 4 teeth corresponds to + (120°) of the circumference, so we machined the 120° range into a spiral shape on both sides of the non-cylindrical body. Accurately fitting into a spiral groove requires a large number of man-hours and processing equipment and jigs.The same applies to fitting into a thin strip of a protrusion.

■It is easy to replace the tip, but the first blade requires a seat that accommodates the tip, so if one part is damaged, the seat for storing the tip will be replaced.
It is necessary to replace the toothed blade.

■Since the holder is bolted at only two places, it will be unstable if the cutting torque is 5 or more.

■Since there is no stopper provided against the force in the circumferential direction, there is no hole, and the bolt is inserted into the hole, so there is a risk that it will move with just the tightening force of the bolt.

(Objective of the present invention) The present invention was made to solve the problems of the conventional products mentioned above, and the blade is easy to process, stable against cutting torque, and has both rigidity and precision. The object is to provide an excellent rotary cutting tool.

(Structure of the present invention) A spiral protrusion having both side surfaces perpendicular to the axis is cut on the outer peripheral cylindrical surface of the main body, and the spiral protrusion is divided and deleted to form a large number of protrusions. , a blade is formed for each cutting edge unit of the chip, and grooves having surfaces parallel to both side surfaces of the blade are provided at the front and rear ends of the blade, and the protrusion of the main body is engaged with the groove of the blade, and the adjacent A clamper is placed between the front and rear ends of the blade, and the blade is fixed with screws.This enables highly accurate machining of the blade, and even if the chip seat of the plate is damaged, the blade will not be damaged. All you need to do is replace the blade.

′-! Since the clamper tightens the blade from both ends, it has excellent effects such as being stable against cutting torque.

(Description of Examples) Next, examples of the present invention will be described. As an example, a throw-away type assembly hob is shown.

The cutting edge wears out like the conventional product with double counter grinding.
In this case, the rake face is not re-ground and used again and again, but only a constant cross section is always used as a cutting edge.

Therefore, there is no need for the plate itself to be spiral, and it is only necessary that the cutting edge formed in a constant cross section be placed on the helical winding of the hob to provide the necessary angles on the side and outer circumference for cutting. Therefore, the shape of the base of the blade that holds the cutting edge may be theoretically of any shape. However, in consideration of compatibility at the time of blade replacement, ease of manufacturing, improvement in mounting strength, processing accuracy, etc., the simplest flat portion was selected in the examples.

First, the protrusions (4) formed on the outer circumferential surface of the cylindrical body (1) (protrusions (4) perpendicular to the axis) are used to increase rigidity and to reduce the manufacturing process. (1).The number of protrusions (4) is the same as that of the blade (2) (
2') The number of pinches is one more than the number of..., and the positions are scattered on the hob's helical winding, and the dividing pinches in the circumferential direction equalize the pitch of the cutting edge of the bob. Further, the protrusion (4) is provided with a stopper (5) for preventing the blade (2) from moving in the circumferential direction due to cutting torque, and the plate (2)
In order to determine the axial position of the + and also to prevent it from moving in the axial direction, the key side (6) and the blade (two cutting edge ends (7) adjacent to the rear end (8) of the plate (2) ) and the screw hole (1υ) is drilled in the protrusion (4) for simultaneously tightening the clamper (9) and the double screw α0 to the main body (1). At this time, the screw hole αυ and the threaded part α4 of the double screw are on the right side. The screw, the screw hole α2 of the clamper (9), and the screw portion Q4 of the double screw (10) are left-handed screws.

The tip (0) of the blade is attached to the tip seat (E).
The bottom surface αQ of each blade (2) (two (two)... is the outer peripheral surface of the main body (1) when the blade (2) (two (2")... (3) It is processed so that it adheres closely.

The surface of the groove (A) which is twisted and engages with the protrusion (4) (one part is machined with a 1000 line mark on the side surface of the blade, and both ends are passed through so that it fits the key side surface (6) of the protrusion (4)). In addition, there are flat lands α perpendicular to the mark Q on the bottom surface of the blade.
9), it is possible to machine an accurate chip seat (A) based on the end face Q barrel and plane land α warp.

Furthermore, the curved surface (2) of the groove (A) against the stopper (5) of each blade is machined so that it makes surface contact with the contact surface (A) on the bust rim side, and the groove (2) on the side of the cutting edge (7) is Since B) does not require the contact surface 12, it is generally counterbore enough to accommodate the double screw 00. Furthermore, since ω), ノ), etc. between each protrusion (4) are deleted, the outer peripheral surface of the main body (
The contact surface between the main body and the blade shown in 3) is extremely small.

The parts where the main body (1) processed as described above and the front and rear ends of the blade are adjacent to each other are tightened using a clamper (9) and a double screw 00). The only tool you need at this time is a hexagonal wrench that fits the hexagonal socket (15) on the head of the double screw Q0. Note that the protrusion (4) is larger than the number of blades because there is no adjacent blade on one side of the first and last blades. It is necessary to form one extra location.

In this example, the bottom surface of the blade (except for the inner cylindrical surface of 1419, each base of the grade is all flat), and the bottom surface (IQ has two flat lands at both ends, so the blade is simple) It can be processed accurately with general-purpose equipment.The main body is also screw-ground] 17 plates can be easily and accurately made, so even assembly type tools with threaded surfaces that are difficult to process can be made with rigidity. Products with good compatibility can be manufactured at low cost.

(Effects of the Invention) In the present invention, as described above, a blade is formed for each unit of the cutting edge of the chip, and the groove of the blade is engaged with the protrusion provided on the outer periphery of the main body, so that the cutting force is not applied. At this time, the abutment surface 12 of the groove at the rear end contacts the abutment surface (A) of the protrusion, so displacement in the circumferential direction is prevented and positioning is performed correctly. In addition, there is little contact surface between the blade and the blade when replacing the tip, so there is less difference between the helical surface of the main body and the flat surface of the plate, allowing for highly accurate assembly. It can be done without using other equipment or jigs, and it has many advantages such as being able to provide inexpensive products.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the arrangement of the plate base with respect to the main body of the embodiment of the present invention, FIG. 2 is a partial perspective view showing the assembly structure of the main body and the blade, and (A) is a partial perspective view of the holder. In the figure, (b) shows a partial perspective view of the blade, (c) shows a partial perspective view of the double screw, and (b) shows a partial perspective view of the clamper. ■...Body 2...Blade 21...Blade 3...Outer peripheral surface of main body 4...Protrusion
5... Stopper 6... Key side 7... Cutting edge end 8... Rear end 9... Clamper 10...
・Double screw 11...Screw hole 12 on the main body...Screw hole 13 on the clamper...Threaded part 14 of the double screw...
Double screw thread part 15...double screw hexagonal hole 16
... Bottom surface of the blade 17 ... Keyway side surface of the blade 1
8...Side surface of the blade 19...End of the bottom of the blade 20...Chip seat 21...Stopper of the plate, S5 surface 22...Surface that the stopper touches Agent Patent attorney Jun Kawauchi 2nd Amendment to Figures and Procedures Date of Schiff, August 1980 Mr. Manabu Shiga, Commissioner of the Patent Office1, Indication of the incident, Patent Application No. 125293 of 1982, 2, Name of the invention, Circulation Cutting Engineer 3, Person making the amendment Relationship with the incident
Patent applicant name (51,9) Fuji Koshi Co., Ltd. 4, agent residence Hidekazu Shiba Park Building 3F, 2-4-1 Shiba Koen, Minato-ku, Tokyo Name (7799) Patent attorney Jun Kawachi 25. Date of order for amendment A. 6. Detailed explanation of the invention in the specification subject to amendment 7. Contents of amendment 7.1 Page 3, line 18 [Necessary protrusions] The phrase "in the stripes of the ridges" should be corrected to "necessary. Also, in the strips of the protrusions." 7.2 On page 6, line 12, "pinch is equal to shi desu." is corrected to "pinch is equal to shi de desu."

Claims (2)

[Claims] (1) In a rotary cutting tool in which a number of blades with throw-away tips are arranged around the outer periphery of a cylindrical body, a spiral protrusion with both sides perpendicular to the axis is formed on the outer cylindrical surface of the body. The spiral protrusions are divided and deleted to form a large number of protrusions, and the blade is cut into the cutting edge 1 of the chip.
Each unit is formed, grooves are provided at the front and rear ends of the blade, the protrusions on the main body are engaged with the grooves on the blade, a clamper is placed between the front and rear ends of adjacent blades, and the blades are tightened with screws. A rotary cutting tool characterized by being fixed. (2) The rotary cutting tool according to claim 1, wherein a thick stopper is provided on one side of the protrusion to receive the cutting force applied to the blade.