JPH0314251Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Purpose of the Invention A-1. Field of Industrial Use This invention relates to an end mill that is generally used when cutting with a milling machine and an end mill holder that tightly holds the end mill.

E-2 Prior Art An end mill holder, also called a milling chuck, is a central part of tooling that can fasten not only end mills but also various straight shank tools.One way to choose an end mill holder is to It is also said that the efficiency of milling processing will change.

Therefore, various improvements have been made to the method of tightening the end mill shank, and FIGS. 4A to 4D are representative examples thereof.

The types of holders are distinguished by the method of fastening the end mill.

In FIG. 4, A is a roll lock type, B is a single side lock type, C is a single collector lock type, and D is a draw screw lock type.

These representative examples also have problems in use,
Selective use was made depending on cutting or usage conditions or restrictions.

E-3 Problems that the invention aims to solve In the conventional fastening devices mentioned above, (1) The single-collection lock type has good runout accuracy of the end mill, but it uses many parts to ensure the holding force. In cutting operations using small-diameter end mills with large heads, the end mills from the operator are hidden behind the head of the holder, obstructing the operator's field of view and making it difficult to see. There have been cases where this has become a hindrance.

(2) The single side lock type and the draw screw lock type had the disadvantage that the end mill was pressed against one side of the hole in the holder, causing the end mill blade to run out. Further, the draw screw lock type has the further disadvantage that the head becomes large.

(3) The roll-lock type has little shrinkage margin for tightening the end mill shank, and the cylindrical end mill shank is closely parallel to the cylindrical shape, and the end of the shank and the area near the blade are evenly tightened. It had the disadvantage that it could not be maintained.

B. Structure of the device B-1. Means for solving the problems In order to solve the above problems, this device has a tool engaging portion close to the blade, an annular groove in the middle, and a screw at the end. an end mill shank, an end mill holder having a tapered hole in the head and a female thread at the bottom of the hole corresponding to the male thread of the shank; It is made up of a split tapered sleeve divided into a plurality of parts, each of which has a protrusion corresponding to the groove of the shank on its inner wall to hold the shank in place.

RO-2 Action If configured as above, the end mill shank 3
Fit the split taper sleeve 2 into the holder 1, and insert it into the tool engaging portion 8 of the end mill shank 3.
When screwed in with a wrench, the groove 4 of the end mill shank 3 and the protrusion 5 of the tapered sleeve 2 engage, and the male thread 6 of the shank is tightened into the female thread 7 of the holder 1. , taper sleeve 2
an outer peripheral tapered surface 11 and a tapered surface 9 on the inner surface of the holder.
is in contact, and the end mill stop position 10
At the same time that the end mill shank 3 stops tightening and is seated, the axes of the end mill and the holder coincide, bringing the end mill into a tightened state.

RO-3 Embodiment An embodiment of this invention will be described with reference to the drawings.

FIG. 1 shows an assembled state in a side sectional view of an embodiment of the invention.

In Fig. 2, the end mill shank 3 has the following:
A tool engaging portion 8 is provided near the blade portion, followed by a groove 4, and a screw 6 is provided at the end.

In Figure 3, the two-split tapered sleeve 2
are a set of two, with a taper 11 on the outer periphery, an inner diameter for tightening the end mill shank 3 on the inside, and a protrusion 5.
is provided.

In FIG. 4, the holder 1 has a taper 9 on the inner surface.
A female thread 7 is provided.

Two tapered sleeves 2 are fitted into the end mill shank 3, and the grooves 4 of the shank 3 are engaged with the protrusions 5.

Fit this into the hole of the holder 1, push in the end mill and taper sleeve, and at the stopped position, apply a spanner to the engagement part 8 of the shank 3 and screw it in, the male thread 6 of the shank 3, The female thread 7 of the holder 1 is fitted, and the tapered sleeve 2 is tightened as it enters the hole of the holder 1, and the tapered surface 11 on the outer periphery of the tapered sleeve 2,
When the tapered surface 9 on the inner surface of the holder contacts and the end mill stop position 10 is reached, the end mill shank 3
At the same time as the tightening stops, the axes of the end mill shank 3 and the holder 1 align, and the end mill shank is brought into a tightened state.

(See Figure 1) Effects of the invention According to this invention, the structure is simple and the number of parts is small, so the end mill holder head can be made smaller, and the operator's field of view during work is wider. , the cutting edge of the end mill becomes easier to see, and the holder head is less likely to hit the workpiece when machining the bottom surface of a stepped part, making it easier to see the end mill's cutting edge.
There is no need for multi-layered chucks, which reduces work difficulties and allows for more efficient work. In addition, since it is a draw screw type, there is no axial relief even when used for heavy cutting.
Not only does it not loosen, it has a large tightening force and holding torque. Furthermore, the tapered sleeve can be tightened to the fullest extent required for cutting, which has the effect of improving the cutting resistance of small-diameter end mills, allowing the end mill to demonstrate its full performance. .

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an embodiment of this invention. FIG. 2 is a perspective view of the end mill shank. FIG. 3 is a perspective view of one of the two split tapered sleeves. FIG. 4 is a partial perspective sectional view of the end mill holder. FIG. 5 is a front view of the split taper sleeve. FIG. 6 is a partially cut side view of the same as above. 7th
The figure is a side view of the flanged taper shank to which the holder of this invention is attached. FIG. 8 is a side view showing a conventional end mill shank fastening device for an end mill holder. 1...End mill holder, 2...Split taper sleeve, 3...End mill shank, 4...Slot, 5...Protrusion, 6...Male thread, 7...Female thread.

Claims (1)

[Scope of utility model registration request] A tool engaging part near the blade part, an annular groove in the middle,
an end mill shank having a thread at its end; an end mill holder having a tapered hole in the head and a female thread at the bottom of the hole corresponding to the male thread of the shank; and an end mill holder interposed between the end mill shank and the end mill holder. An end mill shank and an end mill holder comprising a split taper sleeve divided into a plurality of parts and having protrusions corresponding to the grooves of the shank formed on the inner wall to securely hold the shank in the holder.