Patent Application
20170021432
The present invention relates to a machine tool, and more particularly to a high-precision cutter holder that can hold a cutter firmly.
This section provides background information related to the present disclosure which is not necessarily prior art.
With the reference to
The body 60 has two ends, a fastening portion 61, and an inner socket 62. The fastening portion 61 is disposed at one of the ends and is provided with an external thread 611 and a fastening portion end face 612. The inner socket 62 and the fastening portion 61 are arranged at the same end of the body 60, the inner socket 62 is a tapered hole which extends from one of the ends of the body 60 to the other end. The collet 70 has two ends, a conjoint portion 71, a fastening cap abutting portion 72, and an annular groove 73. The conjoint portion 71 is cone-shaped, corresponds to the inner socket 62 in sectional shape, and is disposed at one of the ends of the collet 70. The fastening cap abutting portion 72 is disposed at the other end of the collet 70. The annular groove 73 is disposed between the conjoint portion 71 and the fastening cap abutting portion 72. The annular groove 73 has a first face 731 and a second face 732, and the first face 731 and the second face 732 are parallel in radial direction. The annular groove 73 has two sides. The first face 731 is located at the side of the annular groove 73 which is adjacent to the conjoint portion 71. The second face 732 is located at the other side of the annular groove 73 which is adjacent to the fastening cap abutting portion 72.
A contact area is defined between the inner socket 62 of the body 60 and the conjoint portion 71 of the collet 70. Since the contact area is small, the collet 70 protrudes from the body 60 at a large distance. The fastening portion end face 612 and the first face 731 of the collet 70 are separated by a distance W1 between 3.5 millimeters (mm) and 3.7 mm. With the small contact area, the force for the body 60 clamping the collet 70 is weak and the cutter 80 is deflected easily. Moreover, the body 60 and the fastening cap 90 of the conventional cutter holder are connected by screwing and a gap is formed between the external thread 611 of the fastening portion 61 and the inner thread 91 of the fastening cap 90. When the conventional cutter holder spins rapidly, the gap causes vibration easily, and the body 60 fails to abut against the collet 70. The problems mentioned above cause poor balance of the conventional cutter holder and reduce machining accuracy.
To overcome the shortcomings of the conventional cutter holder, the present invention provides a firmly assembled high-precision cutter holder to mitigate or obviate the aforementioned problems.
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
An aspect of the present invention is to provide a firmly assembled high-precision cutter holder that can perform machining precisely during rapid spinning.
The cutter holder comprises a body, a collet, a cutter, and a fastening cap. The cutter is inserted into the collet. The collet is assembled on the body with the cutter. The fastening cap is mounted on the body. The cutter protrudes from the fastening cap. The body has a fastening portion. The collet has an annular groove. The fastening portion has a fastening portion end face. The annular groove has a first face. The fastening portion end face and the first face are separated by a distance. By means of confining the distance between the fastening portion end face and the first face to increase a contact area between the body and the collet, insufficient clamping force of the conventional cutter holder can be resolved. The present invention provides a firmly assembled high-precision cutter holder that can steadily clamp the collet for precise machining.
Other aspects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
The drawings described herein are for illustrative purposes only of a selected embodiment and not all possible implementations, and are not intended to limit the scope of the present disclosure.
An example embodiment will now be described more fully with reference to the accompanying drawings
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The fastening portion end face 111 of the body 10 and the first face 231 of the collet 20 are separated by a distance W2. The present invention confines the distance W2 between 0.1 mm and 0.6 mm. Compared with the conventional cutter holder, the distance W2 is smaller than the distance W1 of the conventional cutter holder. The smaller distance W2 can increase the contact area between the inner socket 115 of the body 10 and the conjoint portion 21 of the collet 20. The larger contact area between the inner socket 115 and the conjoint portion 21 can increase the clamping intensity, which can thereby resolve the conventional cutter holder's drawback that vibrations are generated easily. The first abutting portion 44 and the second abutting portion 45 of the fastening cap 40 abut against the first abutting face 113 and the second abutting face 114 of the body 10 respectively, thereby reducing generation of vibrations while the cutter holder spins rapidly.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “includes,” “including,” “having,” “has”, and “have,” are inclusive and therefore specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof.
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
