JPS62130146A - Dual spindle arrangement capable of adjusting cut-depth - Google Patents

Abstract

PURPOSE:To make it possible to adjust the cut-depth at a low cost, by fixing gears having reversely twisted angles to inner and outer spindles eccentrically journalled, by meshing a helical gear on one and the same axis, and by moving this helical gear in the axial direction. CONSTITUTION:An inner spindle 5 is journalled in an outer spindle 4, eccentric therewith. A tool fitting hole 6 is formed in the inner spindle 5 at the front end of the latter, eccentric with the spindle 5. Gears 7, 8 having reversely twisted angles are fixed to the outer and inner spindles 4, 5, the gear 8 being meshed with an inner tooth gear 11. The outer diameter of the gear 7 is equal to that of the inner tooth gear 11. A helical gear 9 is integrally incorporated with gears 9a, 9b having reversely twisted angles on one and the same axis. When a thread shaft 10 is rotated, the helical gear 9 is moved in the axial direction so that the inner and outer gears 7, 11 are rotated in opposite directions so that the rotational phases of the inner and outer spindles 4, 5 vary, thereby the rotational phases of the main spindles are shifted correspondingly. With this arrangement, the cut-depth of a tool varies, and therefore, it is possible to adjust the cut-depth with a cheap device.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to, for example, the main spindle structure of a machine tool having a tool radius compensation mound, and provides a simple method for correcting the tool radius by adjusting the depth of cut of a tool in the radial direction. This relates to a two-east spindle structure that allows the depth of cut to be adjusted.

Conventional technology As a means to change the depth of cut in the radial direction by moving the cutting edge of 'U, IL: fitted into the spindle in and out, conventional methods have used a face plate with a tool slider or used an eccentric tool holder. etc. have been adopted, but the operability is poor,
Another drawback was that automatic adjustment was not possible. As a solution to this problem, there is a conventional technique disclosed in Japanese Patent Publication No. 49-18398. The inner main shaft, which is eccentrically supported by the outer main shaft, is driven by a drive source, and the outer main shaft is rotated at the same speed and in the same direction as the inner main shaft via a differential gear device.

a phase adjustment device is associated with the differential gearing;
The coaxial phase with the outer and inner main axes is adjusted. In other words, it is characterized by having a differential gear device as its main element. Although the above-mentioned drawbacks are solved by the present invention, the structure is complicated and the number of parts is large, so that high-precision adjustment is difficult.

Problems to be Solved by the Present Invention The present invention solves the above-mentioned missing Q, etc. It has a simple structure, a small number of parts, and is capable of adjusting the cutting depth so that the entire device can be formed with high precision and at low cost. The purpose is to provide a double main axis structure.

Means for Solving the Problems For this purpose, the present invention fixes gears with opposite helix angles to the outer main shaft and the inner main shaft eccentrically supported on the outer main shaft, and fixes gears with opposite helix angles on the same axis. The means is a double main shaft structure in which the amount of cutting can be adjusted by meshing helical gears formed integrally with each other and moving the helical gears in the axial direction by a moving means.

The operating helical gear is moved by a predetermined amount in its axial direction, the outer and inner main shafts are rotated in opposite directions to change the rotational phase, and the position of the tool insertion hole is changed to adjust the depth of cut. Note that this operation is effective even while the main shaft is rotating.

Example Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, an outer main shaft 4 is pivotally supported within the quill l via a bearing 2.3. Furthermore, an inner main shaft 5 is pivotally supported eccentrically within the outer main shaft 4. The eccentricity e is expressed by the distance between the center o1 of the outer main shaft 4 and the center 02 of the inner main shaft 5, as shown in FIG. A hole 6 into which a tool (not shown) is inserted is formed on the distal end side of the inner main shaft 5. The hole 6 is formed eccentrically with respect to the inner spindle 5 (the amount of eccentricity is e). Specifically, the shank of the tool is fitted into the hole 6, and the cutting edge of the tool is arranged to face the radial direction of the spindle. be done. Gears 7.8 having opposite helix angles are fixed to the outer main shaft 4 and the inner main shaft 5, and the internal gear 11 meshes with the gear 8.

The gear 7 and the internal gear 11 are formed to have the same outer diameter (pitch diameter).

The reason why the gear 8 and the internal gear 11 are used is to cancel the eccentricity of the outer and inner main shafts 4.5 and to rotate them smoothly.

The helical gear 9 is formed by integrally forming gears 9a and 9b having opposite helix angles to the same axis, and the gears 9a and 9b are arranged to mesh with the gear 7 and the internal gear 11, respectively. The gears 9a and 9b are rotatably supported by the screw shaft 10, which is the above-mentioned moving means.
It is formed to be movable in its axial direction by rotation of. A motor 12 for driving the screw shaft lO is connected to the screw shaft lO.

Further, a gear 14 connected to the main shaft rotation motor 13 meshes with the internal gear 11 (or the gear 7).

Next, the operation of this embodiment will be explained.

When the motor 12 is rotated, the screw shaft 10 rotates, and the helical gear 9 moves in the axial direction. This causes the gear 7 and the internal gear 11 to rotate in opposite directions, and the outer and inner main shafts 4
．． Change the rotation phase of 5. Therefore, the phases of the outer and inner principal axes are shifted by this amount.

On the other hand, the inner main shaft 5 can be rotated by operating the main shaft rotation motor 13. In this case, the helical gear 9 also rotates as the internal gear 11 rotates, and the gear 7 is also rotated by the gear 9a, but the inner main shaft 5 is rotated by the outer main shaft 4. There is no problem because it is supported by a central axis.

Further, by rotating the string motor 12 while the inner main shaft 5 is rotating, the same phase change as described above can be provided.

Adjustment of the depth of cut of the tool cutting edge will be explained with reference to FIG.

As described above, the outer main shaft 4 and the inner main shaft 5 are eccentric by the eccentricity tie, and the tool hole 6 is also eccentric by the eccentric amount e.

Therefore, the hole 6 is the center O of the inner main shaft 5? Radius e centered at
(eccentricity amount) circle 15h. Now the rotation phase angle is θ
Then, the cutting depth a of the cutting edge becomes as shown in the following formula.

a=e(1-casθ) Therefore, in order to obtain the predetermined depth of cut a, the rotational phase may be adjusted by an angle θ that satisfies the above equation.

In this embodiment, the eccentricity e between the outer main spindle 4 and the inner main spindle 5 and the eccentricity e of the tool hole 6 are set to be the same value, but the present invention is not limited to this.

This embodiment is a simple one using a helical gear 9 with an integral structure, and can be implemented at low cost with a small number of parts.Each component can be processed and assembled with high accuracy, improving overall accuracy.
You can do it.

Effects of the Invention As is clear from the above description, the present invention has the advantage of having a simple structure, being able to be implemented at low cost, and improving the accuracy of the device.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, and FIG. 2 is an explanatory diagram for explaining the depth of cut of a tool. l...quill, 2.3. ...Bearing, 4... Outer spindle, 5...Inner spindle, 6@...hole, 7°8.1
4...Gear, 9...Helical gear, 9a, 9b...
・Gear, 10...screw shaft. 11--Internal gear, 12--Motor, 13--Main shaft rotating motor, 15--Kisten. 1 figure

Claims (1)

[Claims] Consists of an outer main shaft that is pivotally supported by the quill, and an inner main shaft that is eccentrically supported within the outer main shaft and has an eccentric hole drilled into which a tool is inserted, and adjusts the rotational phase of the outer and inner main shafts. In the double spindle structure formed to adjust the cutting depth of the tool in the radial direction, coaxial shafts are fixed to the outer and inner spindles and are coaxial to simultaneously mesh with gears formed at opposite helix angles. A double main shaft structure capable of adjusting the depth of cut, characterized in that a helical gear formed by integrally forming a gear with a reverse helix angle on a line is provided, and a moving means for moving the helical gear along its axis is provided.