JPH0615506A - Centering device of machine tool - Google Patents

Abstract

PURPOSE:To provide a centering device of a machine tool capable of heightening machining precision of a work. CONSTITUTION:On a spindle 1 of a machine tool, an installation member 5 installed in an attachable/detachable manner and a work supporting body 6 forming a work installation part 11 holding a work in an attachable/detachable manner are provided, on one surface of facing surfaces of the installation member 5 and the work supporting body 6, a plural number of installation holes 14 are formed, and on the other surface of the facing surfaces of the installation member 5 and the work supporting body 6, installation screws 15 to be inserted into the installation holes 14 with specified play are provided. Consequently, at the time of fixing the installation member 5 on the spindle 1, by firmly connecting the installation member 5 and the work supporting body 6 by fixing force of the installation screws 15 after displacing the center of the work supporting body 6 within a range of play of the installation screws 15 and the installation holes 14, slippage of the center of the spindle 1 and the work installation part 11 is restrained within small tolerance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centering device for machine tools.

[0002]

2. Description of the Related Art First, FIG. 3 shows a conventional example. Reference numeral 1 is a cylindrical spindle. Although not shown, the spindle 1 constitutes a part of a machine tool such as a lathe,
Rotational force is applied by the motor. Further, the machine tool is provided with a fixing screw 3 which protrudes while rotating from a hollow hole 2 formed in the center of the spindle 1.

Reference numeral 50 denotes a work mounting core metal. The work mounting core metal 50 has a mounting surface 51 that contacts the end surface of the spindle 1 and a work mounting portion 11 that holds the work 16.
Have and. A cylindrical boss 8 which is inserted into the hollow hole 2 of the spindle 1 with a slight play is formed at the center of the mounting surface 51, and the boss 8 is screwed to the fixed screw 3 at the center thereof. A screw hole 9 is formed.
A stepped portion 12 that expands is formed at one end of the work attachment portion 11, and a work fixing screw 13 is formed at the other end.

To mount the work mounting core 50 on the spindle 1, first, the boss 8 is inserted into the hollow hole 2. In this state, the hollow screw 2 and the boss 8 are fitted to each other so that the center deviation between the fixed screw 3 and the screw hole 9 is set within a certain allowable range. Next, the hollow hole 2 is set to a negative pressure state, and the mounting surface 51 is sucked to the end surface of the spindle 1 by negative pressure to temporarily fix the work mounting core metal 50. In this state, while rotating the fixing screw 3, the fixing screw 3 is advanced in the axial direction and screwed into the screw hole 9, whereby the work mounting core 50 is fixed to the spindle 1. The work 16 fitted into the work mounting portion 11 is fixed between the stepped portion 12 and a nut (not shown) screwed into the work fixing screw 13. Therefore, the work 16 is processed by rotating the spindle 1 together with the work mounting core 50 and the work 16 and bringing a tool (not shown) into contact with the work 16.

[0005]

A clearance of the order of μm is required between the hollow hole 2 of the spindle 1 and the boss 8 of the work mounting core 50 due to manufacturing tolerances.
As a result, the centers of the spindle 1 and the work mounting core 50 are easily displaced. Therefore, the processing accuracy of the work 16 is reduced, which is not suitable for precision processing.

[0006]

According to the present invention, there is provided a mounting member which is removably mounted on a spindle of a machine tool, and a work support body having a work mounting portion which holds a work in a removable manner. A plurality of mounting holes are formed on one surface of the member and the work support facing each other, and the mounting holes are inserted into the mounting hole with a predetermined play on the other surface of the mounting member and the work support facing each other. It is provided with a mounting screw.

[0007]

When the mounting member is fixed to the spindle of the machine tool, the center of the work support is displaced within the play between the mounting screw and the mounting hole, and then the mounting member and the work support are separated by the tightening force of the mounting screw. Can be firmly coupled, and by this, the deviation of the center between the spindle and the work mounting portion can be suppressed within an extremely small allowable range. Therefore, the processing accuracy of the work can be improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The same parts as those described with reference to FIG. 4 is a work mounting core,
The work mounting core 4 includes a mounting member 5 and a work support 6. The mounting member 5 has a mounting surface 7 that contacts the end surface of the spindle 1 of the machine tool, and a cylindrical shape that is formed at the center of the mounting surface 7 and that is inserted into the hollow hole 2 of the spindle 1 with a slight play. Boss 8 and this boss 8
And a screw hole 9 which is formed at the center of and is screwed into the fixed screw 3. A flange 10 and a work attachment portion 11 are formed on the work support 6. A stepped portion 12 that expands is formed at one end of the work attaching portion 11, and a work fixing screw 13 is formed at the other end. In addition, the flange 10 has three mounting holes 14 approximately 120.
The mounting member 5 is provided with three mounting screws 15 which are inserted at predetermined intervals into the mounting holes 14 with a predetermined play.

In such a structure, as described above,
Mounting member 5 in contact with the end surface of spindle 1 of machine tool
The mounting member 5 can be fixed to the end surface of the spindle 1 by screwing the fixing screw 3 of the machine tool into the screw hole 9 of the. In this case, loosen the mounting screw 15
After displacing the center of the work supporting body 6 within the range of play between the mounting hole 14 and the mounting hole 14, the mounting member 5 and the work supporting body 6 can be firmly coupled by the tightening force of the mounting screw 15. As a result, the deviation of the center between the spindle 1 and the work mounting portion 11 can be suppressed within an extremely small allowable range. Therefore, the processing accuracy of the work 16 can be improved.

To align the center of the work mounting portion 11 with the center of the spindle 1, for example, a measuring instrument such as an electric micro is fixed to the bed of a machine tool, and the spindle 1 is manually rotated to rotate the outer periphery of the work mounting portion 11. Deflection of surface Measure while measuring with an electric micro.

Although the work support 6 is fixed by the head of the mounting screw 15, a mounting screw without a head is fixedly erected on the mounting member 5, and a nut screwed to these mounting screws is used. The work support 6 may be fixed.

[0012]

According to the present invention, a mounting member detachably mounted on a spindle of a machine tool and a work support having a work mounting portion for holding a work detachably are provided. A plurality of mounting holes are formed on one surface of the surface facing the support, and a mounting screw inserted into the mounting hole with a predetermined play is formed on the other surface of the surface facing the mounting member and the work support. Since it is provided, when the mounting member is fixed to the spindle of the machine tool, the center of the work support is displaced within the play between the mounting screw and the mounting hole, and then the mounting member and the work support are tightened by the tightening force of the mounting screw. Can be firmly coupled to each other, and thereby, the deviation of the center between the spindle and the work mounting portion can be suppressed within an extremely small allowable range. Therefore, there is an effect that the processing accuracy of the work can be improved.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention and is a side view with a partial cross section.

FIG. 2 is a front view of a work support.

FIG. 3 shows a conventional example and is a side view in which a part is shown in section.

[Explanation of symbols]

 1 Spindle 5 Mounting member 6 Work support 11 Work mounting part 14 Mounting hole 15 Mounting screw 16 Work

Claims (1)

[Claims] 1. A mounting member removably mounted on a spindle of a machine tool, and a work support having a work mounting portion for removably holding a work. The mounting member and the work support are provided. A plurality of mounting holes are formed on one surface of the facing surface, and a mounting screw to be inserted into the mounting hole with a predetermined play is provided on the other surface of the facing surface of the mounting member and the work support. Characterizing machine tool centering device.