JPH09229083A - Slide bearing for vibrating tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent decrease in accuracy of linear guide by detecting a load only at the time of oscillation of a tool applied to an equally divided bearing and a load when a load is applied, and controlling displacement of slide bearing by the difference therebetween. SOLUTION: When a clearance is generated between the slide surface of slide bearing 2 divided into three segments and the outer circumferenttial surface of a tool 1, caused by wear on the slide surface, the detected load by load detection parts 4a-4c, 4A-4C at the time of oscillation only in the same as that detected at the time of no substantial wear. However, when a load F is acts to an end of the tool 1, a load is applied to e.g. a part corresponding to the side of load detection parts 4b and 4c. The difference between the cases at the time of only oscillation and load F applied is calculated vby a control part, displacemetn control input levels 8a-8c, 8A-8C are supplied to a displacement control part, and the displacement control part is controlled by a piezoelectric element so that the detection load is the same as that at the time of no substantial wear on the slide surface. With the compensation mechanism, decrease in accuracy in the linear guide part of vibrating tool caused by increase in crearance can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding bearing for a vibrating tool, which suppresses an increase in clearance due to wear of a sliding surface of a sliding bearing of a tool linear guide of a vibrating tool for plastically deforming a workpiece by vibration of the tool. Regarding

[0002]

2. Description of the Related Art A conventional sliding bearing for a vibrating tool will be described. FIG. 6 is a sectional view showing the schematic structure thereof.

The outer peripheral surface of the rod-shaped tool 1 in FIG. 6 is supported by the inner peripheral surface of the slide bearing 2, and the oscillation mechanism 3 is provided at the upper end of the tool 1 via a block 1a having a diameter larger than that of the tool 1.
The vibration is transmitted to the tool 1 by the oscillation action of the oscillation mechanism 3.

On the outer peripheral surface of the tool 1, a spring 1 is provided between the upper end surface of the slide bearing 2 and the lower surface of the block 1a.
1 is interposed and receives the force of pushing up the tool 1 by the elastic force of the spring 11.

The tool 1, the slide bearing 2, the oscillation mechanism 3, and the spring 11 are housed in the main body 9. The lower part of the tool 1 projects from the lower end surface of the main body 9. Tool 1
The lower end of is shaped like a cone and its tip is sharpened,
Due to the oscillating action of the oscillating mechanism 3, the tip of the tool 1 is pressed against the upper surface of the workpiece 10 to perform predetermined processing on the upper surface of the workpiece.

Next, the operation of the plain bearing for a vibrating tool will be described. First, by starting the oscillation mechanism 3,
The oscillation energy of the oscillation mechanism 3 is transmitted to the tool 1 and the spring 11 through the block 1a, and the tool 1 and the spring 11 vibrate.

The vibration of the tool 1 includes the vibration energy of the spring 11 in addition to the oscillation energy directly received from the oscillation mechanism 3. The tool 1 receives both vibration energy and vibrates laterally with respect to the axis, and is loaded in the direction of the axis so that the tip of the tool 1 performs a predetermined machining on the machining surface of the workpiece 10. . At this time, if the velocity of the kinetic energy of the tool 1 is increased, the work piece 10 is efficiently plastically deformed as impact energy.

For example, the tool of the air type vibrating pen is a flanged shaft having a sharp tip on a cone.
High-speed vibration (600H)
The amplitude is about 2 mm at z-200 Hz). Small indentations are made continuous in the workpiece 10 by the collision energy of the vibration of the tool, and a character pattern or the like is machined.

Next, the sliding bearing 2 for linearly guiding the tool 1 of the vibration tool will be described. The sliding surface of the sliding bearing 2 is
It is lubricated by fluid lubrication, which regularly supplies oil, and solid lubrication, which has a lubricating effect on the material itself.

[0010]

However, the sliding bearing 2
The reciprocating vibration of the tool 1 on the sliding surface of the tool temporarily stops at the stroke end (speed becomes 0), and it is difficult to form the lubricating film at this moment. Therefore, due to the high-speed vibration and the load applied to the tip of the tool 1 during machining, wear of the slip surface is promoted, which leads to an increase in clearance.

An increase in clearance causes a decrease in precision of linear guide, uneven wear due to uneven contact surface pressure, and increase in motion resistance. Therefore, the life of the tool 1 is shortened.

[0012]

In order to solve this problem, a sliding bearing for a vibrating tool according to the present invention is provided with a work piece 10.
Tool 1 that collides with the work piece 10 to cause plastic deformation in the workpiece 10, a slide bearing 2 that bears the tool 1 and linearly guides it, and is equally divided by a bearing surface, and each of the equally divided slides. Each slide bearing is detected by detecting the load applied to the bearing 2 only when the tool 1 vibrates and the load applied to each slide bearing 2 when a load "F" is applied to the tool 1 and the difference between the detected values of the both loads. And a correction mechanism for controlling the displacement of No. 2 are provided.

[0013]

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a plain bearing 2
Is divided into equal parts and the tool 1 is linearly guided, and the load applied to the slide bearing 2 only when the tool 1 vibrates is detected by the correction mechanism, and the slide bearing 2 when the load F is applied to the tool 1 is detected. The load to be applied is detected, and the displacement of the equally divided slide bearing 2 is corrected from the difference between the detected values of the both loads.

Next, embodiments of the sliding bearing for a vibrating tool according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view showing the configuration of the embodiment. In FIG. 1, the same parts as those of the conventional example of FIG.

The tool 1 shown in FIG. 1 is formed into a rod shape so that an object to be processed (not shown) can be plastically deformed and machined as in the case of the conventional example, and the lower end thereof is a cone. It is in the shape of. The upper end of the tool 1 is connected to the oscillation mechanism 3 via a block 1a formed to have a diameter larger than that of the tool 1, and the outer peripheral surface of the tool 1 has a slide bearing 2 (characteristics of the slide bearing 2 in this embodiment). The physical composition will be described later).

A spring 11 is wound around the outer peripheral surface of the tool 1 between the upper end surface of the slide bearing 2 and the block 1a, as in the case of the conventional example. The configuration so far is the same as that of the conventional example of FIG.

FIG. 2 is a plan view of the main part in FIG. As is clear from FIGS. 1 and 2, the sliding bearing 2
Is equally divided into any number. The embodiment shown in FIGS. 1 and 2 shows a case where the image is divided into three parts.

The tool 1 is supported by the inner peripheral surface of each slide bearing 2 divided into three equal parts, and the load detecting portion 4a by a piezoelectric element is provided at the upper end portion of the outer peripheral surface of each slide bearing 2. 4c is attached. Similarly,
At the lower end portion of the outer circumference of each slide bearing 2, load detecting portions 4A to 4C by piezoelectric elements are attached. The load detectors 4a to 4c and 4A to 4C are arranged on the circumference.

As the piezoelectric element used here, for example,
The "Piezoelectric ceramic actuator" described in Chapter 9, Section 1 of the "Actuator Utility Dictionary" issued by Fuji Techno System Co., Ltd. is used.

This piezoceramic actuator incorporates thick film technology to produce (1-x-y) Pb) Ni _1/3 Nb.
_2/3 ) O _3-x PbZrO _3-y PbTiO ₃ piezoceramic material, which is a three-component solution of the same solution, is heat-treated, and a predetermined number of layers are stacked to form a layer. The area of a large number of layered electrodes formed through the disassembly process was made to match the cross-sectional area of the device, the interlayer voltage of the internal electrodes was made uniform, the internal electrodes were connected in parallel, and the external electrodes were applied. It is also.

The "applied voltage vs. generated displacement characteristic" of this piezoelectric ceramic actuator shows that the displacement is substantially proportional up to an applied voltage of about 100 V, and at a voltage higher than that, the displacement is saturated and the displacement when the voltage drops is The displacement tends to be slightly larger than when the voltage rises.

The "voltage-distortion response characteristic" has a characteristic in which the strain follows a sharp change in the applied voltage.

Further, regarding the "force-displacement characteristic", for example, the displacement is about 6 μm with respect to a mechanical load when a DC voltage of 100 V is applied between the internal electrode and the external electrode.

Each load detection section 4 using such a piezoelectric element
Displacement control parts 5a to 5c and 5A to 5C by the same piezoelectric element as described above for controlling the displacement of each slide bearing 2 are attached to the outer peripheral sides of a to 4c and 4A to 4C.

The tool 1, the slide bearing 2, the oscillation mechanism 3, the spring 11, and the load detectors 4a to 4c and 4A to 4 described above.
C, the displacement control units 5a to 5c, and 5A to 5C are housed in the main body 9. The lower end of the tool 1 penetrates the main body 9 and faces the processing surface of a workpiece (not shown).

Output levels 7a-of the load detectors 4a-4c
7c and output levels 7A to 7 of the load detectors 4A to 4C
Each C outputs a detection voltage to the control section 6. From the output end of the control unit 6,
As displacement control signals, displacement control input levels 8a to 8c,
8A to 8C, that is, the displacement voltage is the displacement control units 5a to 5C.
c, 5A to 5C.

These load detectors 4a to 4c, 4A to 4
C, the displacement control units 5a to 5c, 5A to 5C, and the control unit 6 constitute a correction mechanism.

Next, the operation of this embodiment configured as described above will be described with reference to FIGS. First, the action when the sliding surface of the sliding bearing 2 vibrates without wear (radial clearance 0) will be described with reference to FIGS. 3 and 4.

FIG. 3 is a characteristic part of the present invention, that is, the tool 1, the slide bearing 2, and the load detectors 4a to 4c, 4 respectively.
A to 4C, displacement control units 5a to 5c, 5A to 5C, output levels 7a to 7c, 7A to 7C, displacement control input level 8a.
8C and 8A to 8C are perspective views showing parts taken out. FIG. 4 is a sectional view showing the tool 1, the slide bearing 2, the load detecting portions 4b and 4c, and the portions 4A and 4C taken out.

As shown in both FIGS. 3 and 4, when only the vibration is applied (the load F is not applied to the tool 1, the load F is
(When = 0), the load applied to the plain bearing 2 is 0, so the load detectors 4a to 4c and 4A to 4C at that time
The force applied to the load detecting unit 4a-4c, 4A-4C does not change based on the above-mentioned "force-displacement characteristic", and the voltage does not change. Therefore, the load detecting units 4a-4c, 4A-4C are not changed.
The detected load detected by the output level 7a = 7b = 7
c = 0, 7A = 7B = 7C = 0.

Further, by using the tool 1, the applied load F = F
When 0 acts on the tip of the tool 1, the load detectors 4a to 4c, depending on the load applied to the slide bearing 2 at this time,
A force acts on 4A to 4C, and the load detection units 4a to 4c and 4A to 4C are based on the "force-displacement characteristic" and the slide bearing 2
The force applied to is detected, and the detected load detected is the output level 7a = 7A ≦ F0,7b = 7B ≦ F0,7c = 7.
C ≦ F0.

Next, the action of the sliding bearing 2 at the time of vibration when a clearance is generated between the outer peripheral surface of the tool 1 due to wear on the sliding surface will be described with reference to FIG. 5 is similar to FIG. 4, the tool 1, the slide bearing 2, the load detecting portions 4b and 4c, 4A and 4C.
It is sectional drawing which took out the part.

In FIG. 5, the load detected by the load detectors 4a to 4c and 4A to 4C of the load applied to the slide bearing 2 only when the tool 1 is vibrated without the applied load F (the applied load F = 0). Is the output level 7a = 7b = 7
c = 0, 7A = 7B = 7C = 0, which is the same as when not worn, but when the load load F = F0 acts on the tip of the tool 1, the load is applied to the slide bearing 2 at this time. In the example of FIG. 5, a load is applied to the upper end side and the lower end side of the slide bearing 2 depending on how the load is applied.
A load is applied to the parts corresponding to the b and 4C sides.

In accordance with this load, the load detectors 4b and 4C
A force is applied to the element to displace it, resulting in a change in voltage.

In this case, the load detected by the load detectors 4a to 4c and 4A to 4C of the load applied to the plain bearing 2 are output levels 7a ≠ 7A, 7b ≠ 7B, 7c ≠ 7.
C. Output levels 7a to 7c, 7A of this detected load
7C, that is, the difference between the detected load of the sliding bearing 2 when only vibration is applied and the detected load of the sliding bearing 2 when the applied load F = F0 acts on the tip of the tool 1 at the control section 6. Calculate and calculate from control unit 6 to displacement control unit 5
Displacement control input levels 8a to 8c and 8A to 8C, which are displacement voltages, are supplied to a to 5c and 5A to 5C, respectively, so that the detected load of the sliding bearing 2 becomes the same as when the sliding surface is not worn. Displacement control units 5a to 5c by elements,
Control 5A to 5C.

That is, the displacement controllers 5a-5c, 5A-
By applying the control input levels 8a to 8c and 8A to 8C to 5C, the displacement control sections 5a to 5c and 5A to 5C are displaced based on the above-mentioned "applied voltage vs. generated displacement characteristic", and this displacement causes slippage. The clearance generated between the bearing 2 and the outer peripheral surface of the tool 1 is corrected.

Therefore, even if a load F is applied to the tip of the tool 1 and the sliding surface of the sliding bearing 2 is abraded, a clearance is not formed between the sliding surface of the sliding bearing 2 and the tool 1. The slide bearing 2 can be displaced.

As described above, by using the correction mechanism, it is possible to control the displacement of the slide bearing 2 which is equally divided, and in the case of overload or when the friction limit between the tool 1 and the slide bearing 2 is exceeded. When an alarm means (not shown) is driven by the output of the control unit 6 to generate an alarm and the sliding bearing for a vibrating tool is incorporated in an automatic machine,
It is possible to save labor in the part that has conventionally relied on human judgment.

[0039]

As described above, according to the sliding bearing for a vibrating tool of the present invention, the sliding bearing for linearly guiding the tool is equally divided, and the load and the tool applied to the equally divided sliding bearing only when the tool vibrates. Since the displacement of the slide bearing is controlled by the correction mechanism according to the difference from the load of the slide bearing when a load is applied to it, it is possible to prevent the accuracy of the linear guide part of the vibrating tool from decreasing due to increased clearance. It is possible to extend the life of the vibrating tool.

Further, it becomes possible to output an alarm such as an overload or a friction limit over between the tool and the sliding bearing, and when incorporated in an automatic machine, it is possible to save labor in a part which has hitherto depended on human judgment. , More useful value comes out.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a configuration of an embodiment of a sliding bearing for a vibrating tool according to the present invention.

FIG. 2 is a plan view showing an essential part of the sliding bearing for a vibrating tool in FIG.

FIG. 3 is a perspective view showing the constituent members of essential parts of the sliding bearing for a vibrating tool shown in FIG.

FIG. 4 is a cross-sectional view of a slide bearing and a load detection portion for explaining the action of the slide bearing for a vibrating tool in FIG. 1 when a load F is not applied to the tool during vibration.

5 is a cross-sectional view of a slide bearing and a load detection portion for explaining the action of the slide bearing for a vibrating tool in FIG. 1 when a load F is applied to the tool.

FIG. 6 is a cross-sectional view showing a schematic configuration of a conventional sliding bearing for a vibrating tool.

[Explanation of symbols]

 1 Tool 2 Sliding Bearing 3 Oscillation Mechanism 4a-4c, 4A-4C Load Detection Section 5a-5c, 5A-5C Displacement Control Section 6 Control Section 7a-7c, 7A-7C Load Detection Output Level 8a-8c, 8A-8C Displacement Control input level

Claims (2)

[Claims] 1. A tool (1) for machining by colliding with a work (10) and causing plastic deformation of the work (10), and bearing the tool (1) to linearly guide and a bearing surface. When the load (F) is applied to the tool (1) and the load only when the tool (1) that is applied to the slide bearing (2) that is evenly divided by the above and each of the slide bearings (2) that is equally divided is applied. The sliding bearing for a vibrating tool, characterized in that the sliding bearing (2) is provided with a correction mechanism that detects the load applied to each sliding bearing (2) and controls the displacement of each sliding bearing (2) based on the difference between the detected values of the two loads. . 2. The sliding bearing for a vibrating tool according to claim 1, wherein the correction mechanism uses a piezoelectric element bonded to an outer peripheral surface of each upper end of each of the equally divided sliding bearings (2).
Load detectors (4a) to (4c) that detect the load only when vibrating (1) and the load when the load "F" acts on the tool (1),
(4A) to (4C), a control section (6) that outputs a displacement control signal in accordance with the difference between the detected load only when the vibration is applied and when the applied load "F" is applied, and each slide bearing (2 ) Is used to input the displacement control signal from the control section (6) using the piezoelectric element bonded to the outer peripheral surface of each lower end to correct the clearance between the tool (1) and the slide bearing (2). Displacement control units (5a) to (5c), (5A) to (5
A plain bearing for a vibrating tool, which is provided with C).