JPH0780766A - Assembly jig - Google Patents

Abstract

PURPOSE:To provide a jig which fixes an H-type steel and an L-type steel securely and solidly as component members in assembling a working frame, a timbering stand and the like. CONSTITUTION:This assembly jig consists of a groove form part 1 and a plate form part 2, and two sets of nuts 4 are formed at both ends of the groove form part 1, the flange A of an H-type steel is held by two of bolts 3, and the flange B of an L-type steel is held by a C-type jig C to insert the flange B to projections 5 on the rear side surface of the plate form part 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing an object to be processed (generally a ceramic object) to which ultrasonic processing technology is applied and a method for manufacturing a grooved object.

[0002]

2. Description of the Related Art Ultrasonic vibration is applied to the processing (for example, groove processing = formation) of a workpiece made of a hard and brittle material such as ceramics, especially fine ceramics (both are simply referred to as ceramics hereinafter). The processing technology used is effective. FIG. 3 is a schematic perspective view showing a conventional method for processing a “circular groove having a rotationally asymmetric shape” on a ceramic workpiece. First, ultrasonic vibration is applied to a rotating grindstone 31 having a small diameter (for example, about φ10 mm) and a cut is made in a fixed workpiece 32 from a vertical direction. Next, the grindstone 31 with a shaft is moved with respect to the workpiece 32 so that a desired asymmetrical shape is obtained. When the grindstone 31 with a shaft has finished drawing a desired shape, the processing ends, and a "rotationally asymmetrical circumferential groove 33" is formed in the workpiece 32.

When machining a circumferential groove, there is also a method of using a cup grindstone for ultrasonic grinding (Japanese Patent Laid-Open No. 63-267150). This cup grindstone is obtained by brazing the grindstone to the edge of a cup-shaped base metal designed to vibrate ultrasonically at a specific frequency. Circular grooves can be processed by pressing the cup grindstone vertically against the workpiece while rotating. However, since the tool has to be rotated, the grooves are limited to "rotationally symmetrical circumferential grooves".

[0004]

The above-mentioned conventional techniques have the following problems. If a cup grindstone is used, it is possible to process (form) a “rotationally symmetrical circumferential groove”. However, in this method, although ultrasonic waves are used, since the processing method is grinding, the tool must be rotated. Therefore, it is impossible to process "a rotationally asymmetrical circumferential groove". That is, a grindstone with a shaft can only be used to process a "rotationally asymmetric circumferential groove". However, in the case of a grindstone with a shaft, since the lateral feed speed is low, it takes a long time to reach the end point of processing. Further, therefore, tool wear occurs in the grindstone with a shaft during processing. This wear reduces the diameter and length of the grindstone, so that the desired groove shape cannot be obtained near the end point of processing. As described above, due to the abrasion of the grindstone, the precision of the shape of the processed groove is lowered. In addition, a grindstone must be brazed when manufacturing a tool. The brazed portion may disturb the vibration state of ultrasonic waves. Therefore, the desired resonance frequency may not be obtained, or the amplitude required for processing may not be obtained, which may hinder the processing.

The present invention has been made in view of the above problems, and an object thereof is to shorten the processing time and improve the accuracy of the processed shape.

[0006]

In view of the above, the present invention provides a cup-shaped ultrasonic machining tool having a "working surface formed in conformity with the shape of a rotationally asymmetrical circumferential groove" as a workpiece. On the top, with abrasive grains (preferably used in the form of a suspension in which abrasive grains are dissolved) interposed, by applying relative pressure while applying ultrasonic vibration to the tool or the workpiece,
A "rotationally asymmetric circumferential groove" is machined (formed) on the workpiece.

[0007]

The cup-shaped ultrasonic machining tool (hereinafter referred to as a cup-shaped tool) used in the present invention is preferably designed by the finite element method so that the shape itself vibrates at a certain resonance frequency. The working surface of the cup-shaped tool is made according to the shape of the "rotationally asymmetric circumferential groove" to be machined. Therefore, a groove having the same shape as that of the work surface is transferred to the workpiece. The groove is processed by applying ultrasonic vibration to the cup-shaped tool or the workpiece to vibrate them, and with abrasive grains interposed between the cup-shaped tool and the workpiece,
It is performed by pressing the cup-shaped tool relative to the work piece. The abrasive grains are generally used in the form of a suspension obtained by suspending the abrasive grains in a suitable liquid (eg, water or oil).

[0008] In the conventional processing using a grindstone with a shaft, the grindstone with a shaft must be fed in the lateral direction to form a groove. Therefore, in the case of a workpiece made of a high hardness material such as ceramics, the feed rate cannot be increased because the grinding resistance increases, and the processing requires a long time. However, according to the present invention, the route along which the grindstone with the shaft is fed can be collectively processed, so that the processing time can be shortened easily.

Furthermore, since there is no starting point and ending point of machining as in the case of a grindstone with a shaft, there is no difference in shape accuracy depending on the location. Further, when a grindstone with a shaft is used, the grindstone is clogged, spilled, or crushed due to the processing, and the grindstone must be frequently retouched. Especially in high hardness materials such as ceramics, the frequency increases. In contrast,
In the present invention, even if the abrasive grains that are the cutting edges are crushed by the processing (a state in which the grindstone is crushed), new abrasive grains flow into the abrasive grains, so that there is no need to make a sharp edge. If you dare
It is only necessary to replace the suspension in the tank after processing for a few hundred hours. The labor is negligible compared to the frequency of ultrasonic grinding.

However, it is necessary to form a shape in which the groove shape is reversed in the tool in accordance with the groove shape to be formed in the workpiece. However, steel is sufficient as the material of the tool, which is easier than forming grooves in ceramics. Further, since this tool can be repeatedly used, this also contributes to shortening the processing time. Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0011]

1 is a schematic perspective view showing an embodiment of the present invention. The ultrasonic vibration system used in the present embodiment is a bolted Langevin type vibrator (not shown) which serves as an external excitation source.
It is composed of an amplitude amplification horn 4 and a cup-shaped tool 1 connected to this horn. FIG. 2 is a schematic vertical sectional view of the cup-shaped tool used in this example. The tool is designed with a diameter of 90 mm in the maximum diameter portion. Work surface (that is,
The contact surface with the work piece) is made to have the same planar shape as the "rotationally asymmetric circumferential groove" to be processed. Although the material of the tool is alloy tool steel, it is not limited to this and may be stainless steel or carbon steel, for example. The cup-shaped tool 1 is designed to vibrate at a predetermined resonance frequency (for example, 22 kHz) by the finite element method.

Alumina ceramics was used for the work piece. In processing the "rotationally asymmetric circumferential groove", first, the cup-shaped tool 1 is moved by the ultrasonic vibration system.
Is ultrasonically vibrated so that the amplitude (for example, 10 μm to 30 μm) necessary for processing is obtained. Then, the suspension 6 in which water and abrasive grains are mixed is poured onto the fixed workpiece 2 so that the entire surface to be processed is covered. Where suspension 6
Is supplied from the suspension supply hose 7. Abrasive grain is B ₄ C
(Boron Carbide) # 280 was used.

Then, the vibrating cup-shaped tool 1 is
A constant load (for example, 20N to 3) is applied to a desired position of the workpiece 2.
0N) and press from the vertical direction (indicated by arrow S in the figure). A shock is transmitted to the work piece 2 through the abrasive grains by the ultrasonic vibration, and the working progresses, so that the "rotationally asymmetrical circumferential groove 3" is formed in the work piece 2. In this embodiment, the depth is 0.2.
mm, the groove having the shape shown in FIG. 1 was processed. The time required for this processing was 5 minutes.

Next, for comparison, a small diameter (diameter φ10 m
Using the diamond grindstone (# 270) with a shaft of m), a rotationally asymmetric groove having a diameter of 90 mm and a depth of 0.5 mm was machined in the alumina ceramics (workpiece) in the same manner as in the example. The processing was performed by moving the fixed workpiece 32 so as to form the groove shown in FIG. At this time, the lateral feed speed of the grindstone was set to about 5 mm / min. The time required for this processing was 60 minutes.
When machining with this method, compared to the starting point of machining, at the end point,
The groove width was reduced by 0.1 mm and the working depth was reduced by 0.05 mm.

As described above, according to this embodiment, the processing time of the groove is about 1/10 of the conventional one, and the processing time can be greatly shortened.

[0016]

EFFECTS OF THE INVENTION In conventional ultrasonic grinding using a cup grindstone, only "rotationally symmetrical circumferential grooves" can be processed. On the other hand, according to the present invention, it is possible to machine a "rotationally asymmetrical circumferential groove" by performing ultrasonic machining using a cup-shaped tool. Further, since the tool can be integrally formed, the tool is less expensive to manufacture than the ultrasonic grinding process using the cup grindstone. Moreover, since no grindstone is used,
Eliminates the need to grind stones. Therefore, the ultrasonic vibration due to brazing is not disturbed, and a good vibration state is maintained.

On the other hand, compared with the case of using a grindstone with a small-diameter shaft, the lateral feed motion of the grindstone is unnecessary, so that a "rotationally asymmetric circumferential shape" is applied to high hardness ceramics (workpiece). The "groove" can be easily processed, and the processing time is greatly reduced. Further, in the case of a grindstone with a shaft, the wear of the grindstone had a great influence on the shape accuracy, but for the same reason (the cross feed motion is unnecessary), it is possible to perform machining without any difference in shape accuracy in terms of location. . In addition, since free abrasive grains are used, there is no clogging, spilling, or crushing of the grindstone that occurs when using the grindstone, so a good processing state can be maintained.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of the present invention.

FIG. 2 is a schematic vertical cross-sectional view of the cup-shaped tool used in the above-mentioned embodiment.

FIG. 3 is a schematic perspective view showing a conventional processing method using a grindstone with a small diameter shaft.

[Explanation of symbols]

1 Ultrasonic Processing Tool (Cup Type Tool) 2 Workpiece (Ceramics) 3 Circular Groove 4 Amplitude Enhancing Horn 5a Cup Type Tool Working Surface 6 Abrasive Grain 7 Abrasive Grain (Suspension) Supply Hose 31 With Shaft Whetstone 32 Workpiece (ceramics) 33 Circular groove or more

Claims (2)

[Claims] 1. A cup-shaped ultrasonic machining tool having a "working surface formed in accordance with the shape of a rotationally asymmetrical circumferential groove to be machined" and abrasive grains interposed between the machined work and the workpiece. In this state, the tool or the workpiece is ultrasonically vibrated while being pressed relatively to the workpiece, thereby processing a "rotationally asymmetric circumferential groove" in the workpiece. . 2. A cup-shaped ultrasonic machining tool having a "working surface formed in conformity with the shape of a rotationally asymmetrical circumferential groove to be machined" and abrasive grains interposed between the machined work and the cup-shaped ultrasonic machining tool. In this state, the tool or the workpiece is ultrasonically vibrated while being pressed relatively to the workpiece, thereby processing a "rotationally asymmetrical circumferential groove" on the workpiece. The manufacturing method of the featured grooved workpiece.