JPS6337125Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a rotary cutting tool having a straight shank. Conventional cutting tools of this type include drills, end mills, reamers, and the like. There are various types of holders that hold these rotary cutting tools.
Typical examples are shown in Figure 1 and Figure 2.

In Fig. 1, the cylindrical straight shank 5 is held only by the taper collet 3, so if the tool is subjected to an abnormal thrust load or cutting torque, or if the tool has a large thrust load or cutting torque, the tool shank will shank inside the taper collet 3. Multi-axis Cannot be used in drilling machines, transfer machines, machining centers, etc. In order to compensate for this drawback, a holder shown in FIG. 2 is used. In FIG. 2, a drive piece 8 that receives a cutting torque and an adjustment screw 11 that receives a thrust load and adjusts the tool length are individually housed in the main body 1. A keyway 10 is provided in the longitudinal direction of the shaft for receiving cutting torque during cutting and adjusting the tool length, so that the drive piece 8 can freely move in the axial direction. In particular, to hold tools with large thrust loads and cutting torques, such as drills, a flat tongue is attached to the rear of the straight shank, and the tongue part is attached to the flat of the straight shank on the drive piece 8 as shown in Figure 2. The taper collet 3 in Fig. 1 is inserted and fixed by tightening with the taper collet 3.
The thrust load and cutting torque can be sufficiently supported by the drive piece 8 and adjustment screw 11, but if the tool is attached to a machine and used, there is a possibility that the tool will wear out or break during cutting. When doing so, you will have to change tools midway. In the holder shown in Figure 2, the adjustment screw 11 must be operated from above the through hole 2 in the figure with a screwdriver or wrench, and even if the tool can be replaced with the holder attached to the machine, the protrusion length of the tool is When adjusting the length, the adjusting screw 11 cannot be operated from the outside, so even if a new tool or a reground tool is attached to the holder, the predetermined tool protrusion length cannot be achieved. When drilling a large number of holes with a certain depth or machining a large number of fixed side surfaces, remove the holder from the machine every time you change the tool, operate the adjustment screw after changing the tool, and adjust the tool. It is very inconvenient that the tool must be fixed to a holder and then attached to the machine according to the required protrusion length, so it cannot be easily used in multi-spindle drilling machines, transfer machines, machining centers, etc. Further, a pin 9 is driven into the drive piece 8 so as to protrude from both ends, and both ends of the pin 9 can freely move in the longitudinal direction of the axis of the keyway 10 and support cutting torque. Therefore, in the rotary tool holder of this machine, when the outer diameter of the drive piece 8 storage portion becomes smaller, the strength decreases by the provision of the keyway 10, and there are major drawbacks such as being subject to manufacturing constraints due to a decrease in rigidity. be.

Embodiments shown in FIGS. 4, 5, and 6 have been devised to solve the above-mentioned drawbacks. FIG. 4 shows that the tongue support 17 is inserted into the adjustment screw 11 with a thread formed on the outer periphery, and the pin 23 is inserted into the adjustment screw 11.
Drive it into the pin hole 22 to integrate it and adjust the adjustment metal 2.
4 is formed. The adjustment piece integrated in this way is housed in the main body 1 as shown in FIG. 6, and serves both the function of the adjustment screw and the function of the drive piece. Further, by forming the adjustment screw 11 with a left-hand thread on the right-hand tool and a right-hand thread on the left-hand tool, the thrust load and cutting torque received from the tool can be sufficiently supported. By using the rotary tool holder of the present invention, tools can be replaced due to wear or breakage of the tool cutting edge during cutting, while the holder remains attached to the machine. Adjustments can be made easily by inserting the tool and rotating it by hand to the left or right. Also, since there is no keyway in the main body, it has the advantage of being highly rigid and can be applied to tools with wide dimensions.

Embodiments of this invention will be explained below with reference to FIGS. 4, 5, and 6. The adjustment screw 11 has a cut 1 in the axial direction.
An elongated hole 13 is provided continuously to 2 and the cut 12 and penetrates through it. Further, the adjustment screw 11 is provided with an insertion hole into which a tongue support metal 17 is inserted. This insertion hole is formed of a conical hole 14 and a cylindrical hole 15. The tongue support 17 is formed with a cylindrical portion 21 whose outer circumferential surface 19 is slightly smaller than the root diameter of the adjustment screw 11 and a conical portion 20 connected to the cylindrical portion 21 . Cylindrical part 2
1 has a hole 22 perpendicular to the axis, and a tongue insertion groove 18 formed at the end. Adjustment screw 11
Insert the cylindrical shape 21 of the tongue support 17 into the conical hole 14 of the adjustment screw 11 until the surface of the conical shape 20 of the tongue support 17 comes into contact with the surface of the conical hole 14 of the adjustment screw 11. The pin holes 22 of the tongue support metal 17 are facing each other, and the pin holes 23 are driven into the pin holes to connect them.

Adjustment screw 11 combined and integrated as shown in Fig. 4
Then, screw the tongue support 17 into the main body 1 along the screw 2 at the rear end of the main body 1 in FIG. 6 (from the top in the figure). (Hereinafter, the combination of the adjustment screw 11 and the tongue support metal 17 will be referred to as an adjustment metal.) Insert the straight shank 5 with a tang into the opening of the tightening nut 4 of the main body 1 that houses the adjustment metal 24,
When the tongue 25 is seated in the tongue insertion groove 18, the adjustment piece 24 and the straight shank 5 are connected, and when the tool is rotated by hand, the adjustment piece also rotates and moves up and down in the figure, so the tool cannot be rotated. After determining the tool protrusion length, tighten the tightening nut 4. The tightened taper collet 3 is pushed upward in the drawing along the tapered surface 6 of the main body 1. Thus, the taper collet 3 is bent and the inner circumferential surface 7 presses against the outer circumferential surface of the tool shank 5, thereby strongly gripping the tool. In Figure 6, a left-hand threaded adjustment metal was used for the right-hand tool. If an excessive cutting torque is applied to the tool during cutting and the shank 5 slips inside the taper collet 3, the adjustment bolt 24, which rotates simultaneously with the main body 1,
The side surface of the tongue insertion groove 18 also slips and presses the tongue 25. Then, due to the drive action of the tongue 25, the adjustment piece advances downward, and naturally the tool is also pushed downward. However, since the cutting edge of the tool is in contact with the workpiece, the tool is actually
7 will be pushed up. In other words, tongue 25
pushes up the tongue support 17 and is pushed into the adjustment screw 11. The surface of the conical portion 20 of the pushed-in tongue support 17 presses against the surface 14 of the conical hole of the adjusting screw 11. Slot 1 on adjustment screw
2, it is pushed outward and the adjustment screw 1
1 bites into the screw 2 of the main body and is strongly locked. Since the locked adjustment screw 11 is temporarily strongly fixed to the main body and rotates together with the main body, the tongue support 17 and the tool, which are interlocked via the pin 23, are also fed with normal rotation. These machines operate instantly and fully support thrust loads and cutting torque, allowing stable cutting to continue.

Adjustment screw 11 of integrated adjustment metal 24 of the present invention
The connecting surfaces of the tongue support and the tongue support are a conical surface and a cylindrical surface, and they are connected by a pin 23, and the twisting direction of the adjustment screw is opposite to the twisting direction of the cutting blade, so thrust loads and cutting Not only can it sufficiently support the torque, but even if the tool slips due to a thrust load or cutting torque that exceeds the cutting conditions during cutting, the adjustment screw will contact the slope of the tongue support and expand in the radial direction. It bites into the thread of the main body and is strongly locked, allowing normal cutting to continue. Moreover, it is easy to manufacture. This rotary tool holder allows for stable cutting due to the synergistic effect of locking the adjustment screw, and the tool protrusion length can be easily adjusted by hand while rotating the tool after changing the tool from outside the machine, making it easy to use and versatile. Suitable for dedicated machines such as shaft drilling machines, transfer machines, and machining centers. In addition, there are many advantages such as the rigidity of the holder itself is high.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the conventional product, Fig. 2 is a sectional view of the same, Fig. 3 is a side view of Fig. 2, Fig. 4 is an assembly diagram of the adjustment metal of the present invention, and Fig. 5 is A of Fig. 4. -A sectional view,
FIG. 6 is a sectional view of an embodiment of the present invention. 1...Body, 2...Inner thread, 3...Taper collet, 4...Tightening nut, 5...Straight shank, 6...Tapered inner circumferential surface, 7...Tapered collet inner circumferential surface, 8...Drive piece , 9...pin, 10...keyway, 11...adjustment screw, 12...
...Slot, 13...Elongated hole, 14...Adjustment screw conical surface, 15...Cylindrical surface, 16...Notch, 17
...Tongue support metal, 18...Tongue insertion groove, 19
...outer peripheral surface, 20...conical part, 21...cylindrical part,
22...Pin hole, 23...Pin, 24...Adjustment metal, 25...Tang.

Claims (1)

[Scope of utility model registration request] A rotary tool holder having a taper collet for holding a straight shank tool in the rotary tool holder and a nut for tightening the taper collet, and housing an adjustment screw for adjusting the tool protrusion length and receiving a thrust load inside the holder, The adjusting screw has an axial slot and an elongated hole connected to the slot perpendicular to the axis, and a conical hole and a cylindrical hole are connected in the axial direction from the end surface of the slot. A tongue support part to be inserted into the hole is formed with a tongue support part having a tongue insertion groove, a conical part in contact with the conical hole, and a cylindrical part to be inserted into the cylindrical hole. A rotary tool holder that uses an adjustment screw with a hole provided, a pin inserted through the elongated hole of the adjustment screw into a pin hole provided in the cylindrical part of the tongue support, and the twisting direction of the screw is opposite to that of the tool.