JPH06238525A - Manufacture of block for direct acting machine element - Google Patents

Abstract

PURPOSE:To facilitate high precision manufacture of a block capable of directly acting through a ball bearing by finishing a straight part of a ball bearing transfer groove in specified surface roughness by polish machining after forming it by wire electrical discharge machining at first. CONSTITUTION:In a device in which a block 2 for a direct acting machine element is smoothly moved and guided along a rail for the direct acting machine element as a large number of ball bearings endlessly cycle in ball bearing transfer grooves 6, straight parts of the ball bearing transfer grooves 6 are formed in surface roughness of 6-8mum firstly by wire electrical discharge machining. Thereafter, they are machined by polish machining so that they are formed in surface roughness of 0.5-1mum. Consequently, by machining the straight parts of the ball bearing transfer grooves 6 by wire electrical charge machining, deterioration of measurement is not caused even if an electrical discharge machining device is continuously driven, and long time continuous machining can be made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a block 2 for a linear motion mechanical element which is one of the parts used in a linear motion mechanical element as shown in FIG. In particular, it relates to a method for processing the ball bearing transfer groove 6 of the block 2 for a linear motion mechanical element.

[0002]

2. Description of the Related Art Conventionally, a block for a linear motion mechanical element is shown in FIG.
Of the ball bearing transfer groove 6 is formed by using a material having a cross section as indicated by the outline line of FIG. 2, and removing a semicircular groove as shown by the hatched portion 7 in FIG. Had formed. More specifically,
Precisely align the material of the cross-sectional shape with the pallet,
Fixed and set. On the other hand, adjust the dresser shape of the engraving whetstone. That is, the curvature of the circumferential surface of the disk-shaped grindstone is precisely processed into a desired size and shape. Then, while rotating the engraving grindstone around the rotation axis, the rotation axis is moved to abut a predetermined position on the corner of the inner surface of the material. In this way, the corners of the inner surface of the material are shaved off to form semi-circular grooves.

In order to form the ball bearing transfer groove at the corner of another position, the material is reset on the pallet,
If necessary, readjust the dresser shape of the engraving whetstone,
Then, the engraving grindstone is brought into contact with a predetermined position on the inner surface of the material to perform grinding processing.

In addition, the crowning portions 62 (see FIG. 3) on the entrance side and the exit side of the ball bearing transfer groove are formed in separate steps.

[0005]

However, the conventional method of manufacturing a block for a linear motion mechanical element has the following problems.

Problem 1 The dimensional accuracy of the formed ball bearing transfer groove depends on the shape of the dresser of the engraving stone used for processing. This engraving stone gradually wears during the grinding process, and its dresser shape gradually changes. For this reason, the dresser shape of the engraving grindstone must be frequently adjusted, and the size and shape of the ball bearing transfer groove must be confirmed after the grinding process, and fine correction must be performed based on the result. There is a lot of manual work, and the dimensions of the ball bearing transfer groove
There is a problem that the shape is not constant and there are variations depending on the skill of the worker. There is a problem that a lot of manual work is required and mechanization and unmanned work cannot be performed. A lot of manual work,
There is a problem that work time is long.

Problem 2 Each time a ball bearing transfer groove is formed at another corner,
There is a problem that the material cannot be continuously operated because the material must be manually set on the pallet again. In addition, the position of the material set on the pallet subtly affects the position of the ball bearing transfer groove to be formed, and it takes time and attention to set, or the position of the ball bearing transfer groove is not constant. There is.

Problem 3 The surface roughness or surface roughness due to ordinary grinding is 1 to 1.
The limit is 5 μm. As a result, when the ball bearing is mounted in the ball bearing transfer groove for use, the movement of the ball bearing is not smooth and a large noise is generated.

Problem 4 There is a problem in that the crowning portion of the ball bearing transfer groove cannot be machined by grinding and another machining step must be provided.

Therefore, an object of the present invention is to provide a new and useful method for manufacturing a block for a linear motion mechanical element, which can solve the above-mentioned problems.

[0011]

The above-mentioned object is defined in claim 1.
The method for manufacturing a block for a linear motion mechanical element according to the first aspect of the present invention, that is, the straight portion of the ball bearing transfer groove is first formed by wire electric discharge machining to have a surface roughness of 6 to 8.
Surface roughness of 0.5 to 1μ after polishing
This is achieved by a method for manufacturing a block for a linear motion mechanical element, characterized in that m is set.

Further, the above object is obtained by a method of manufacturing a block for a linear motion mechanical element according to a second aspect of the present invention, that is, a wire electric discharge machining is first performed on the straight portion and the crowning portion of the ball bearing transfer groove. It is also achieved by a method for manufacturing a block for a linear motion mechanical element, which is characterized in that the surface roughness is 0.5 to 1 μm by polishing after forming the surface roughness to 6 to 8 μm.

[0013]

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

FIG. 1 is a perspective view in which a part of the linear motion mechanical element is cut away. FIG. 2 is a central sectional view of the block for a linear motion mechanical element, and corresponds to the section A of FIG. FIG. 3 is a perspective view near the entry side of the linear motion mechanical element block.

The material of the cross section represented by the contour line in FIG. 2 is fixed to the clamp of the electric discharge machine. Stretch between the upper wire guide of the electric discharge machine and the rotation guide of the electric discharge machine,
Wire electric discharge machining was performed by moving a wire fed at a predetermined speed to a predetermined position on the inner surface of the material and applying a voltage between the wire and the material.

First, the straight portion 61 of the ball bearing transfer groove was formed by wire electric discharge machining while keeping the wire perpendicular to the material. The upper wire guide and the rotating guide are interlocked with a computer program and a predesigned path as design data. To prevent coarse chips from falling and changing the discharge conditions,
It is desirable that the chips be small enough to attach to the wire and be removed. Therefore, it is desirable to perform so-called "pocket electric discharge machining", in which the movement path of the wire is made fine.

After the straight portion 61 is subjected to wire electric discharge machining, the crowning portion 62 is automatically formed by wire electric discharge machining without resetting the material.
By controlling the positional relationship between the upper wire guide and the rotation guide, the wire is inclined by a predetermined angle, and the crowning portion 62 on the entry side is formed by wire electric discharge machining. Again, this is done according to computer programs and design data.

As described above, the straight portion 6 of the ball bearing transfer groove is provided at each of the four corners without manpower in the middle.
1. The entry side and the exit side crowning portions 62 are formed by wire electric discharge machining. The surface roughness of the ball bearing transfer groove thus formed was 6 to 8 μm.

Then, the surface of the ball bearing transfer groove is smoothed by polishing to have a surface roughness of 0.5 to 1 μm.
As a result, the processing of the ball bearing transfer groove is completed.

[0020]

According to the present invention, since the ball bearing transfer groove is manufactured by wire electric discharge machining and polishing, the following remarkable effects can be obtained due to its construction.

(1) Due to wire electric discharge machining, dimensional deterioration does not occur even during continuous operation. As a result, continuous machining can be performed for a long time, and it is not necessary to confirm the dimensions of the formed ball bearing transfer groove or to perform fine adjustment based on it.

(2) The ball bearing transfer grooves can be machined in the four corners without re-fixing the material in the clamp of the electric discharge machine during the process. Therefore, unmanned continuous operation can be performed. Moreover, not only the straight portion but also the crowning portion can be continuously operated unmanned.

(3) Since the ball bearing transfer groove is extremely smooth, when the ball bearing is mounted and the linear motion mechanical element is used, the movement of the ball bearing becomes smoother and almost no sound is produced.

[Brief description of drawings]

FIG. 1 is a perspective view in which a part of a linear motion mechanical element is cut away.

FIG. 2 is a central sectional view of a block for a linear motion mechanical element.

FIG. 3 is a perspective view near the entry side of a block for a linear motion mechanical element.

[Explanation of symbols]

 1 Rail for linear motion mechanical element 2 Block for linear motion mechanical element 3 End plate for linear motion mechanical element 4 End seal for linear motion mechanical element 5 Ball bearing 6 Ball bearing transfer groove 61 Straight part of ball bearing transfer groove 62 Ball bearing transfer Groove crowning 7 Shaded area

Claims (2)

[Claims] 1. A surface roughness of 6 to 8 which is formed by wire electric discharge machining first on the straight portion of the ball bearing transfer groove.
Surface roughness of 0.5 to 1μ after polishing
A method for manufacturing a block for a linear motion mechanical element, characterized in that m is set. 2. The straight and crowning portions of the ball bearing transfer groove are first formed by wire electric discharge machining to have a surface roughness of 6 to 8 μm, and then polished to have a surface roughness of 0.5 to 1 μm. A method for manufacturing a block for a linear motion mechanical element.