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KR-20260064732-A - machine tool

KR20260064732AKR 20260064732 AKR20260064732 AKR 20260064732AKR-20260064732-A

Abstract

[Problem to be solved] Provide a machine tool that facilitates the exchange of a collet chuck to fit the outer diameter of the workpiece. [Solution] An NC lathe (1) for machining a workpiece (W1) held on a first spindle (4), wherein the first spindle (4) is provided with a collet chuck (47) having a chuck body (471) disposed at the tip portion of the first spindle (4) and a gripping portion (472) disposed inside the chuck body (471) to grip the workpiece (W1), and a spindle cap (48) that contacts the tip surface of the chuck body (471) and restricts movement toward the tip of the chuck body (471). The spindle cap (48) has a cap through hole (48a) formed in the center portion that penetrates in the Z1 axis direction, which is the axial direction of the first spindle (4), and the gripping portion (472) is capable of expanding and contracting in a diameter direction perpendicular to the Z1 axis direction, and in the contracted state in the diameter direction, the rear end is located at the rear end side of the cap through hole (48a). The portion (472b) is smaller in diameter than the cap through hole (48a).

Inventors

  • 스기모토 다카시
  • 가와무라 모토히로
  • 아사바 요헤이
  • 스기야마 다케히로
  • 미즈가키 히나코

Assignees

  • 스타 마이크로닉스 컴퍼니 리미티드

Dates

Publication Date
20260507
Application Date
20241002
Priority Date
20231012

Claims (6)

  1. As a machine tool for processing a workpiece held on a main spindle, The above main shaft is equipped with a collet chuck having a chuck body disposed at the tip portion of the main shaft and a gripping portion for gripping the workpiece, and a spindle cap that contacts the tip surface of the chuck body and restricts movement toward the tip of the chuck body. The spindle cap has a cap through hole formed in the central part that penetrates in the axial direction of the main shaft, and The above gripping portion is capable of expanding and contracting in a diameter direction perpendicular to the axis direction, and in the state of contraction in the diameter direction, the rear end portion located at the rear end side of the cap through hole is smaller in the diameter direction than the cap through hole. machine tool.
  2. In paragraph 1, The above gripping portion has an interlocking portion formed on its outer surface, and A machine tool in which the above chuck body has a part that is engaged with the above-mentioned part to restrict movement of the above-mentioned gripping part in the above-mentioned axial direction when the above-mentioned gripping part is expanded in the above-mentioned diameter direction.
  3. In paragraph 1 or 2, A machine tool having the above-mentioned gripping portion having an exposed portion exposed at the tip of the main shaft, and having an exposed concave portion concave in the axial direction at the exposed portion.
  4. In paragraph 1 or 2, A machine tool having a gripping portion that protrudes toward the tip side from the cap through hole.
  5. In paragraph 1 or 2, A machine tool having the above-mentioned gripping portion having a plurality of segmented bodies arranged in an annular shape with a gap in the circumferential direction, and an elastic member disposed between the segmented bodies to press the segmented bodies outward in the diameter direction.
  6. As a machine tool for processing a workpiece held on a main spindle, The above-mentioned main shaft comprises a collet chuck having a chuck body disposed at the tip portion of the main shaft and a gripping portion for gripping the workpiece, and a spindle cap that contacts the tip surface of the chuck body and restricts movement toward the tip of the chuck body. The spindle cap has a cap through hole formed in the central part that penetrates in the axial direction of the main shaft, and The above gripping portion is capable of expanding and contracting in a diameter direction perpendicular to the axis direction, and in the contracted state in the diameter direction, the rear end portion located at the rear end side of the cap through hole is capable of passing through the cap through hole. machine tool.

Description

machine tool The present invention relates to a machine tool for processing a workpiece held on a main spindle. A machine tool for machining a rod-shaped workpiece held on a rotatable spindle is known. This spindle is equipped with a collet chuck for holding the workpiece. On the outer circumferential surface of the collet chuck, a tapered surface is formed that becomes larger in diameter as it faces the tip of the spindle. The collet chuck is covered by a chuck sleeve having an inner circumferential surface similar to the outer circumferential surface of the collet chuck. By moving the chuck sleeve in the tip direction, the tapered surface of the collet chuck is pressed against the chuck sleeve, causing the gripping portion formed on the tip side of the collet chuck to contract in diameter and grip the workpiece. While a general collet chuck is formed as a whole, a collet chuck in which the diameter member and the body diameter member are separate bodies has also been proposed (see, for example, Patent Document 1 et al.). A collet chuck exerts high gripping force by using a gripping portion with an inner diameter that matches the outer diameter of the workpiece being machined. Therefore, when machining a workpiece with an outer diameter different from that of the workpiece being machined so far, a replacement operation is performed during the preparation phase to switch to a collet chuck with an inner diameter that matches the outer diameter of the workpiece. [Fig. 1] This is a front view showing the appearance of an NC lathe related to the present embodiment. [Fig. 2] This is a plan view showing the internal configuration of the NC lathe shown in Fig. 1 in a simplified manner. [Fig. 3] This is a cross-sectional view taken from the front by cutting the first main axis shown in Fig. 2 with a vertical plane passing through the centerline of the first main axis. [Fig. 4] This is a perspective view of the first principal axis shown in Fig. 2. [Fig. 5] This is an enlarged view of section A of Fig. 3. [Fig. 6] This is a perspective view showing the gripping portion of the first main axis shown in Fig. 5. [Fig. 7] This is a right-side view of the first main axis shown in Figs. 3 and 4. [Fig. 8] This is an enlarged view similar to Fig. 5, showing the shape of the gripping part being detached. [Fig. 9] This is an enlarged view similar to Fig. 5 showing a modified example of the gripping part. Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, the present invention will be described using an example in which it is applied to a Swiss-type NC (Numerical Control) lathe. FIG. 1 is a front view showing the appearance of an NC lathe (1) related to the present embodiment. As shown in FIG. 1, the NC lathe (1) is equipped with a cutting chamber (11), a first spindle chamber (12), and an operating section (13) on a base leg. This NC lathe (1) corresponds to an example of a machine tool. The cutting chamber (11) is positioned to the right of the NC lathe (1) when viewed from the front. A cutting chamber door (111) is installed in this cutting chamber (11). By opening the cutting chamber door (111), components such as the second spindle (8) (see FIG. 2) inside the cutting chamber (11) can be replaced. The first spindle chamber (12) is positioned to the left of the NC lathe (1) when viewed from the front. A spindle chamber door (121) is installed in this first spindle chamber (12). By opening the spindle room door (121), parts of components such as the first spindle (4) (see FIG. 2) located in the first spindle room (12) can be replaced. The operating unit (13) is positioned above the first spindle room (12). This operating unit (13) is an input device for operating the NC lathe (1). The operating unit (13) is also equipped with a display device that displays information about the NC lathe (1) or various programs stored in the NC lathe (1). The operator of the NC lathe (1) operates the NC lathe (1) using the operating unit (13). FIG. 2 is a plan view showing the internal configuration of the NC lathe (1) shown in FIG. 1 in a simplified manner. As shown in FIG. 2, inside the NC lathe (1), a control device (2), a first spindle head (3), a first spindle (4), a guide bush (5), a first tool holder (6), a second spindle head (7), a second spindle (8), and a second tool holder (9) are installed. An NC program is stored in the control device (2). The control device (2) is a computer that operates the first spindle head (3), the first spindle (4), the first tool holder (6), the second spindle head (7), the second spindle (8), and the second tool holder (9) by numerical control according to the NC program. In addition, the first tool holder (6) may be equipped with a rotary tool that rotates the tool (T1) for the first spindle itself. Likewise, the second tool holder (9) may also be equipped with a rotary tool that rotates the tool (T2) for the second spindle itself. The