JP2003028267A - Method for working nut screw for top type ball screw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for working a nut screw for a top type ball screw capable of greatly reducing working time comparing with cutting work and effective for enlargement of ball screw size and increase of circulation routes. SOLUTION: In the method for working the nut screw for the top type ball screw, laser beam L is applied to an inner circumference surface from an outer circumference surface of the nut screw 12 having a spiral groove where balls are rolled and a deflector fitting hole 17 passing through the nut screw 12 is provided on the inner circumference surface of the nut screw 12. A deflector forming circulating routes is fitted and fixed in the deflector fitting hole 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of processing a nut screw for a top type ball screw.

[0002]

2. Description of the Related Art A ball screw which converts a rotary motion into a linear motion or a linear motion into a rotary motion is capable of amplifying a small torque to obtain a large thrust force and further capable of performing a precise positioning in a linear direction. Therefore, it is widely used in machine tools, semiconductor-related devices, industrial robots, etc.

In the ball screw, the nut screw 1 of the top type ball screw shown in FIGS. 3 and 4 is provided with a spiral groove 2 on its inner peripheral surface. A deflector fitting hole 4 for fitting and fixing the deflector 3 is provided on the outer peripheral surface of the nut screw 1. The deflector fitting hole 4 is machined in the same shape as the deflector 3 so that the deflector fitting hole 4 can be fitted into the deflector 3 with no gap.

The ball 7 rolls between the spiral grooves 2 and 5 of the ball screw 6 having the spiral groove 5 and the nut screw 1 having the spiral groove 2. Further, the balls 7 are arranged in the infinite circulation path 8 of the ball screw 6, and when the nut screw 1 and the ball screw 6 relatively rotate, the balls 7 form an infinite circulation path via the circulation path of the deflector 3. .

By the way, conventionally, the method for processing the deflector fitting hole 4 is to use a cutting tool such as a drill or an end mill.
Cutting is performed from the outer peripheral surface side of the nut screw 1.
However, in response to the demand for high thrust of the ball screw 6, there is an increase in the size of the ball screw and an increase in the number of circulation circuits. However, in the conventional cutting process, the cutting removal amount increases and the processing time increases proportionally. There is a problem that it will end up.

Further, as a means for firmly fixing the deflector 3 to the nut screw 1, as shown in FIG. 5, a dovetail groove whose width becomes wider as the depth of a deflector fitting hole 4'processed in the nut screw 1 is increased. It has a shape. Then, after the deflector 3 is fitted into the deflector fitting hole 4 ', the deflector 3 is caulked and deformed by the punch 9 to prevent the deflector 3 from falling out of the deflector fitting hole 4'.

[0007]

However, when cutting the nut screw 1 with a cutting tool such as a drill or an end mill, the amount of cutting removal increases as the ball screw size increases and the number of circulation circuits increases. However, the processing time increases proportionally. Further, when the deflector fitting hole 4'to be machined in the nut screw 1 is machined into a dovetail groove shape whose width becomes wider as it goes deeper, a special tool is required for hole machining, which increases machining time and increases machining cost. Is the cause.

The present invention has been made in view of the above circumstances, and an object thereof is to easily process a deflector fitting hole for a nut screw and shorten the processing time to reduce the cost. With
An object of the present invention is to provide a method for processing a nut screw for a top screw, which can easily fix the deflector to the deflector fitting hole and reduce the processing cost.

[0009]

In order to achieve the above object, the present invention provides a method for processing a nut screw for a top type ball screw, wherein a spiral groove for transferring the ball is formed on the inner peripheral surface. Irradiating a laser beam from the outer peripheral surface of the nut screw having, a deflector fitting hole penetrating the inner peripheral surface of the nut screw is provided, and a deflector forming a circulation path is fitted and fixed in the deflector fitting hole. It is a feature of the method of processing the nut screw for the top type ball screw.

According to a second aspect of the present invention, in a method for processing a nut screw for a top type ball screw, a deflector fitting hole that penetrates from an outer peripheral surface of a nut screw having a spiral groove through which a ball is transferred to an inner peripheral surface to an inner peripheral surface is provided. After installing a deflector that forms a circulation path in this deflector fitting hole,
A method of processing a nut screw for a top type ball screw is characterized in that the deflector is laser-welded to the nut screw.

According to the first aspect of the present invention, since the deflector fitting hole is formed by laser processing, the amount of material removed is limited to the contour path of the fitting hole, so that the processing time can be greatly shortened as compared with the cutting processing. Planned.

According to the second aspect of the present invention, the deflector is laser-welded to the nut screw, so that it is not necessary to provide a deflector fitting hole having a special shape for preventing the deflector from coming off, and caulking is performed. Without, it is possible to reduce the processing time.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment, and FIG. 1 is a side view of a nut screw processing apparatus in a top type ball screw. The work support mechanism 11 is provided with a chuck 13 for gripping the nut screw 12, and the chuck 13 positions the nut screw 12 in the circumferential direction and the axial direction by an NC-controlled index 14.

A laser beam machine 15 is formed on the outer peripheral surface of the nut screw 12 at right angles to the axis of the nut screw 12.
The laser irradiation port 16 is provided.
Nut screw 1 by laser light L emitted from
A deflector fitting hole 17 penetrating to the inner peripheral surface of the second outer peripheral surface can be formed.

That is, the chuck 13 moves the nut screw 12 in the circumferential direction and the axial direction by the NC-controlled index 14, and at the same time, the nut screw 12 is moved.
The laser light L from the laser irradiation port 16 is applied to the outer peripheral surface of the. Therefore, the laser light L is scanned along the contour path of the deflector fitting hole 17, and the deflector fitting hole 17 penetrating to the inner peripheral surface of the nut screw 12 is processed. A deflector is fitted in the deflector fitting hole 17 as in the conventional case, and the deflector is fixed to the nut screw 12 by crimping, screwing or the like, or by laser welding which is a second embodiment described below.

By providing the deflector fitting hole 17 by the laser processing as described above, the amount of material removed by the laser is limited to the contour path of the deflector fitting hole 17 unlike the conventional cutting processing, so that the processing time is greatly shortened. Can be achieved.
Therefore, it is effective for increasing the size of the ball screw and increasing the circulation path.

FIG. 2 shows a second embodiment and is a vertical sectional side view of a part of the nut screw 12. The deflector fitting hole 18 formed in the nut screw 12 is formed such that the outer peripheral side of the nut screw 12 is wide and the inner peripheral side is narrow, and a fitting step portion 19 is formed.

The deflector 20 has a shape following the shape of the deflector fitting hole 18, and has an engaging edge portion 21 that engages with the fitting step portion 19. Furthermore, the deflector 20
Chamfered portions 22 are formed on both side edge portions of the.

When the deflector 20 is fixed in the deflector fitting hole 18, the deflector 20 is fitted in the deflector fitting hole 18 and the fitting step portion 19 is engaged with the engaging edge portion 21. In this state, the deflector 20 is fixed to the nut screw 12 by irradiating the joint between the deflector fitting hole 18 and the deflector 20 with the laser beam L from the laser irradiation port 23 of the laser beam machine to perform laser welding.

In this case, the extremely small portion is heated and welded by the laser beam L, the deformation due to heat hardly occurs, and the conventional taper hole processing for preventing the removal by caulking is not necessary, and the processing time is greatly shortened.

[0022]

As described above, according to the first aspect of the present invention, since the deflector fitting hole is formed by laser processing, the material removal amount is limited to the contour path of the fitting hole. Compared with, it is possible to significantly reduce the processing time, which is effective for increasing the size of the ball screw and increasing the circulation path.

According to the second aspect of the present invention, the deflector is laser-welded to the nut screw, so that it is not necessary to provide a deflector fitting hole having a special shape for preventing the deflector from coming off, and caulking is performed. Without this, the processing time can be shortened, and the processing cost can be reduced.

[Brief description of drawings]

FIG. 1 shows a first embodiment of the present invention, and is a side view of a processing device for a nut screw in a top type ball screw.

FIG. 2 shows a second embodiment of the present invention and is a vertical sectional side view of a part of a nut screw.

FIG. 3 is a vertical sectional side view of a conventional nut screw.

FIG. 4 is a vertical sectional side view of a conventional top-type ball screw.

FIG. 5 is a vertical sectional side view of a part of a conventional nut screw.

[Explanation of symbols]

12 ... Nut screw 17 Deflector fitting hole 20 ... Deflector L ... Laser light

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ryuji Iwasawa             Gunma Prefecture Maebashi City 1-8-1 Sojamachi Japan             Within Seiko Co., Ltd. F term (reference) 3J062 AA21 AA28 AA38 AB22 AC07                       BA01 CD04 CD54

Claims (2)

[Claims] 1. A method of processing a nut screw for a top type ball screw, wherein laser light is irradiated from an outer peripheral surface of a nut screw having a spiral groove in which a ball transfers to an inner peripheral surface, and the inner peripheral surface of the nut screw is irradiated. A method for processing a nut screw for a ball-screw type ball screw, characterized in that a deflector fitting hole penetrating through is provided, and a deflector forming a circulation path is fitted and fixed in the deflector fitting hole. 2. A method for processing a nut screw for a top type ball screw, wherein a deflector fitting hole is provided which penetrates from an outer peripheral surface of the nut screw to an inner peripheral surface of the nut screw having a spiral groove for transferring balls on the inner peripheral surface. A method for manufacturing a nut screw for a top-type ball screw, which comprises fitting a deflector forming a circulation path into a deflector fitting hole, and then laser-welding the deflector to the nut screw.