JPWO2018159806A1 - Hammering inspection equipment - Google Patents

Abstract

The hitting sound inspection apparatus according to the present invention includes a product fixing unit for fixing and holding a product (10) on a gantry (20), a hammer head (301) for hitting the product, and a handle (302) for holding the hammer head. ), A motor (303) for driving the handle, a hitting unit (30) having a one-way clutch (340) for connecting the handle and the motor, and a hitting sound hit by the hammer head. A sound collecting unit having a sound collector (40) for detection, wherein the one-way clutch transmits power in a driving direction of the motor to the handle, and transmits power in a direction opposite to the driving direction of the motor. Disconnect.

Description

  A hitting sound inspection device that hits the surface of a product with a hitting tool, determines the attenuation of the generated hitting noise, and detects an internal defect of the product based on a comparison between the attenuation and the reference attenuation indicated by a good product. About.

  As shown in FIG. 10, a disc brake pad 10 used for braking a motorcycle and an automobile has a structure in which a friction material 11 is laminated and fixed on a back plate 12 made of cast iron or steel. I have.

  FIG. 11 shows a manufacturing process of the disc brake pad. The back plate includes a degreasing process for degreasing the back plate, a rust prevention process for performing a rust prevention process, an adhesive application process for applying an adhesive to a surface on which the friction material is fixed, and a drying process for drying the applied adhesive. It is prepared through a process. In addition, the friction material is a weighing step of weighing raw materials each comprising a fiber base material, an inorganic filler, an organic filler, a binder, etc., a mixing step of mixing the weighed raw materials to form a friction material composition, a friction material, The preform is prepared as a friction material preform through a preforming step of filling the composition into a forming apparatus, forming and preforming.

  The disc brake pad is a hot-press forming process in which the prepared back plate and the preform of friction material are stacked together and hot-pressed by a thermoforming press to fix them together, and the resulting hot-pressed body is heated and held Heat treatment step of thermally curing the binder in the friction material composition, a machining step of processing chamfers (11a in FIG. 10) and slits (11b in FIG. 10) of the friction material, and scorch treatment of the friction material surface Through a scorch processing step, a powder coating step of powder coating the side surfaces of the back plate and the friction material, and a machining step of performing final machining.

  In a disc brake pad manufactured through such a manufacturing process, if pores having a predetermined size or more remain in the friction material due to segregation of the friction material composition or the like, the pores become defects and the product life is shortened. For this reason, in the manufacturing process of the disc brake pad, only the products that pass the inspection are subjected to a hitting sound inspection process for inspecting the disc brake pad by hitting sound as a final inspection.

  As shown in FIG. 12, the hitting sound inspection is performed by holding the disc brake pad 10 with one hand and hitting the disc brake pad 10 with the hammer 50 held by the other hand, and the internal sound is generated by the hitting sound generated at that time. This is an operation for determining the presence or absence of a defect. Such a hammering test is a sensory test based on the sound of a skilled worker, and is therefore an evaluation test that largely depends on the skill of the worker.

  By the way, in recent years, the manufacturing industry has been studying labor saving in each manufacturing process in order to reduce the manufacturing cost, and also studying mechanization in hammering inspection.

  Various methods and apparatuses have been proposed for nondestructive inspection of products by hitting sounds, and are applied to various fields. For example, Patent Literature 1 discloses that a hit is applied to the surface of a product with a hitting tool, the attenuation of the generated hitting sound is obtained, and a comparison between the attenuation and a reference attenuation shown by a good product indicates that the internal defect of the product is defective. Is to be detected.

JP-A-03-092758

  In order to mechanize the hammering sound inspection, the present inventors analyzed the situation of the hammering sound inspection by hand. As shown in FIG. While hitting the product (the disc brake pad 10), it has been found that the hitting is performed by a snap hit using a flexion of a wrist, which quickly lifts the hammer 50 upward after the hit. The present inventors have conducted various studies in order to mechanically reproduce this impact situation.

  The present inventors first devised and studied the hammering sound inspection apparatus shown in FIG. 6A, the disc brake pad 10 is placed on the gantry 20 with the back plate 12 down, and the friction material 11 of the disc brake pad 10 is This is a device in which the surface is hit by the hammer head 311 of the hitting unit 31 and the hitting sound generated at the time of hitting is collected by the sound collector 40. The hitting unit 31 includes a hammer head 311, a handle 312 for supporting the hammer head 311, and a motor 313 for rotating and driving the hammer head 311 and the handle 312. The drive of the motor 313 causes the hammer head 311 to rotate the disc brake pad 10. The surface of the friction material 11 is configured to be hit. The present hitting sound inspection apparatus is characterized in that the handle 312 is made of spring steel having high elasticity in order to simulate bending of the wrist.

  However, in this hitting sound inspection device (FIG. 6), the handle 312 is made of spring steel having high elasticity, so that the handle 312 is elastically deformed by the repulsive force of the impact of the disc brake pad 10 as shown by the broken line. As a result, the surface of the friction material 11 of the disc brake pad 10 is hit again by the recovery of the elastic deformation of the handle 312. For this reason, as shown in FIG. 6B, in the waveform of the impact sound collected by the sound collector 40, the impact sound of the second impact is detected as noise, and a normal impact sound waveform is obtained. I couldn't do that.

  Next, the present inventors devised and studied the tapping sound inspection device shown in FIG. 7 includes a hammer head 321, an air cylinder 325 for driving the hammer head 321, and a spring 326 for supporting the hammer head 321. The driving unit 32 drives the air cylinder 325. The hammer head 321 strikes the surface of the friction material 11 of the disc brake pad 10. FIG. 8 shows a hitting state by the present hitting sound inspection apparatus. As shown in FIG. 8A, when the hammer head 321 strikes the friction material 11 of the disc brake pad 10, the air cylinder 325 stops driving before the strike, and the hammer head 321 causes the friction of the disc brake pad 10 due to inertial force. Material 11 was configured to be hit. In the present hammering sound inspection device, the hammer head 321 is raised by the return force of the spring 326 as shown in FIG. It is a feature of the present hitting sound inspection apparatus that such an operation reproduces a snap hit close to a manual operation and prevents a second hit.

  However, in the present hitting sound inspection device (FIGS. 7 and 8), although the snap hit close to a manual operation can be reproduced and the second hit can be prevented, the hitting sound collected is as shown in FIG. In addition, noise accompanying the expansion and contraction of the spring 326 is also detected, and a normal impact sound waveform cannot be obtained.

  Under such circumstances, an object of the present invention is to provide a tapping sound inspection device capable of preventing a second hitting and obtaining a normal hitting sound waveform free from noise. It is an object of the present invention to mechanize the hammering sound inspection which depends on the skill of a person, to save labor, and to reduce the manufacturing cost.

  Based on the above study, the present inventors conducted further studies.By applying a one-way clutch, the repulsive force at the time of impact caused the hammer head to rotate and move in the opposite direction to that at the time of impact, and this reverse direction. It has been found that it is possible to prevent the second strike while allowing the rotational movement, and to acquire a normal strike sound waveform without noise.

  The hitting sound inspection device of the present invention is based on this finding, and specifically, a product fixing unit for fixing and holding a product on a gantry, a hammer head for hitting the product, and a handle portion for holding the hammer head. A motor for driving the handle, a hitting unit having a one-way clutch for connecting the handle and the motor, and a sound collecting unit having a sound collector for detecting a hitting sound hit by the hammer head. The one-way clutch transmits power in a driving direction of the motor to the handle, and disconnects power in a direction opposite to the driving direction of the motor.

  In the hit sound inspecting device of the present invention, it is preferable that the product is held on the gantry via an elastic body, and a magnet is arranged on a part of the elastic body.

  The hitting sound inspection device of the present invention is a device in which a motor and a handle portion holding a hammer head are connected via a one-way clutch, the clutch is disengaged by a repulsive force at the time of hitting, and the hammer head moves in the opposite direction. It allows movement and prevents re-hitting with a clutch.It can reproduce a snap hit close to human hands while preventing a second hit, and can acquire a normal hitting sound waveform without noise. Things. For this reason, it is possible to mechanize the tapping sound inspection depending on the skill of the operator, achieve labor saving, and reduce the manufacturing cost.

It is a schematic diagram which shows an example of the hammering inspection apparatus of this invention. FIG. 2A is a schematic diagram showing a state of a striking sound in the hammering inspection device of the present invention, wherein FIG. 2A is a schematic diagram showing a configuration and operation of the striking device, and FIG. 2B is a schematic diagram showing a state of a one-way clutch. FIG. FIG. 3A is a schematic diagram showing a state of rebound in the hammering inspection apparatus of the present invention, where FIG. 3A is a schematic diagram showing the configuration and operation of a hammer, and FIG. 3B is a schematic diagram showing a state of a one-way clutch. FIG. 4 is a waveform of a hitting sound by the hitting sound inspection device of the present invention. It is a schematic diagram which shows another example of the hammering inspection apparatus of this invention. FIG. 6A is a schematic diagram illustrating an example of the studied hammering sound inspection apparatus, in which FIG. 6A is a schematic diagram illustrating the configuration of the apparatus and an operation at the time of hitting, and FIG. 6B is a waveform of a hitting sound by the present apparatus. It is a schematic diagram which shows the structure of another example of the hammering inspection device examined. 8A and 8B are schematic diagrams showing a state at the time of impact and a rebound state in the hammering inspection device of FIG. 7, wherein FIG. 8A is a schematic diagram showing a state at the time of impact, and FIG. FIG. 8 is a waveform of a hitting sound by the hitting sound inspection device of FIG. 7. It is a schematic diagram which shows the external appearance of a disc brake pad, FIG.10 (a) is a top view, FIG.10 (b) is a side view, FIG.10 (c) is a perspective view. FIG. 4 is a process chart showing a manufacturing process of the disc brake pad. It is a schematic diagram which shows the situation of the hammering inspection by hand.

  FIG. 1 shows an example of a tapping sound inspection apparatus according to the present invention. The hitting sound inspection apparatus shown in FIG. 1 includes a gantry 20 on which the disc brake pad 10 is mounted, a hitting unit 30 for hitting the surface of the friction material 11 of the disc brake pad 10, and a sound collector for collecting a hitting sound generated at the time of hitting. And a sound collection unit including 40.

  The sound collecting unit has a sound collector 40 and a waveform analyzer (not shown) connected to the sound collector 40, and analyzes the striking sound collected by the sound collector 40 by the waveform analyzer. The sound collection unit calculates the degree of attenuation of the struck sound collected by the waveform analyzer, compares the degree of attenuation with a reference degree of attenuation (the degree of attenuation of a non-defective product registered in advance), and detects an internal defect of the product. I do.

  The hitting unit 30 in the hitting sound inspection apparatus of the present invention includes a hammer head 301, a handle 302 for supporting the hammer head 301, and a motor 303 for driving the hammer head 301 and the handle 302 to rotate. In the striking unit 30, the handle 302 and the motor 303 are connected via a one-way clutch 340. The one-way clutch 340 is a clutch that transmits rotation in only one direction from the drive shaft side to the driven shaft, and automatically idles for rotation in the opposite direction. In the hit sound inspecting device of the present invention, the one-way clutch 340 transmits the power of the motor 303 in the driving direction of the motor and disconnects the power of the motor 303 in the direction opposite to the driving direction.

  The hitting state by the hitting unit 30 is shown in FIGS. 2 and 3. As shown in FIG. 2A, by driving the motor 303, the hammer head 301 and the handle 302 holding the hammer head 301 rotate and strike the surface of the friction material 11 of the disc brake pad 10. At this time, the connection state of the one-way clutch 340 is such that the rotating shaft 341 of the motor 303 is inserted into and connected to the one-way clutch 304 and the handle 302 is connected to the outer race of the one-way clutch 340, as shown in FIG. 342, the roller 343 of the one-way clutch 340 is engaged with the rotation of the rotation shaft 341 of the motor 304 (the outer peripheral surface of the roller 343 is the outer peripheral surface of the motor 304 and the inner peripheral surface of the outer ring 342. To the outer ring 342 by wedge action, transmitting the rotation of the motor 304 to the outer ring 342, and rotating the motor 304 to drive the hammer head 301 and the hammer. The handle 32 that holds the head 301 rotates and strikes the surface of the friction material 11 of the disc brake pad 10. The motor 303 stops driving at the time of impact.

  After the impact, as shown in FIG. 3A, the hammer head 301 and the handle portion 302 holding the hammer head 301 are disconnected from the one-way clutch 340 by the repulsive force at the time of the impact, and the rotation of the motor 303 is started. It rotates and moves in the opposite direction. At this time, in the connection state of the one-way clutch, as shown in FIG. 3B, only the outer ring 342 of the one-way clutch 340 rotates in the reverse direction. At this time, the roller 343 of the one-way clutch 340 is disengaged from the meshing position by the rotation of the outer ring 342 and the return force of the spring 344, thereby allowing the outer ring 343 to idle.

  Thereafter, the hammer head 301 attempts to rotate again in the striking direction due to the weight of the hammer head 301. However, since the rotating shaft 341 of the motor is stopped, the rollers 343 of the one-way clutch 340 are engaged when the outer ring 342 tries to rotate. Even if it moves to the position, it will be restrained by the rotating shaft 341 of the motor, the rotation of the hammer head 301 will not occur, and the second impact will be prevented.

  Further, since the sound generated when the one-way clutch 340 is operated is so small that the sound is not captured by the sound collector 40, the waveform of the impact sound by the impact inspection device of the present invention is as shown in FIG. It is good without noise.

  The one-way clutch described in FIGS. 2B and 3B is an example of a mechanism called a roller clutch (freewheel clutch), and is an example in which rollers 343 are provided on an outer ring 342. The rotating shaft 341 may be connected to the inner ring, and rollers 343 may be provided on the inner ring. Instead of the roller clutch, a mechanism such as a sprag type one-way clutch or a cam clutch may be used. That is, the one-way clutch 340 can be used without any problem as long as the power is transmitted in the driving direction of the motor of the motor 303 and the power is disconnected in the direction opposite to the driving direction of the motor 303. Can be used.

  In the hitting sound inspection device of the present invention, the disc brake pad 10 is placed on the gantry 20 with the back plate 12 facing downward and the friction material 11 facing upward, but at this time, it is held via an elastic member. Is preferred. Through the elastic member, soft holding as if held by a human hand becomes possible, and the impact at the time of impact can be absorbed. Examples of the elastic member include rubber such as natural rubber and silicone rubber, and polymer elastomers and foams such as polyurethane.

  In this case, as shown in FIG. 5, it is preferable to dispose the elastic member 210 on the gantry 20 and dispose the magnet 220 on a part of the elastic member 210. By arranging the magnet 220 in a part of the elastic member 210, the back plate 12 made of cast iron or steel can be magnetically attracted by the magnetic force of the magnet 220, and can be fixed and held on the elastic member 210. , And can be held softer. Although the magnet 220 is embedded in the upper part of the elastic member 210 in FIG. 5, it may be embedded in the lower part or inside the elastic member 210.

  Further, the gantry 20 itself may be a magnet chuck, the elastic member 210 may be disposed between the gantry 20 and the back plate 12 made of cast iron or steel, and the back plate 12 may be restrained by the magnetic attraction of the magnet chuck. .

  The hitting sound inspection apparatus of the present invention can reproduce a snap hit close to a human hand while preventing a second hit, and can obtain a normal hitting sound waveform free from noise, thereby saving labor in the manufacturing process. And contribute to reduction of manufacturing costs.

DESCRIPTION OF SYMBOLS 10 Disc brake pad 11 Friction material 12 Back plate 20 Stand 210 Elastic body 220 Magnet 30, 31, 32 Striking unit 301, 311, 321 Hammer head 302, 312 Handle part 303, 313 Motor 325 Air cylinder 326 Spring 340 One-way clutch 341 Motor rotation shaft 342 One-way clutch outer ring 343 One-way clutch roller 344 One-way clutch spring 40 Sound collector (sound collection unit)
50 hammer

Claims (5)

A product fixing unit for fixing and holding the product on a gantry;
A hammer head for hitting the product, a handle for holding the hammer head, a motor for driving the handle, and a hitting unit having a one-way clutch for connecting the handle and the motor;
A sound collecting unit having a sound collector that detects a sound hit by the hammer head,
The hit sound inspection device, wherein the one-way clutch transmits power in a driving direction of the motor to the handle, and disconnects power in a direction opposite to the driving direction of the motor.   The hitting sound inspection device according to claim 1, wherein the product is held on the gantry via an elastic body, and a magnet is arranged on a part of the elastic body.   The hitting sound inspection according to claim 1 or 2, wherein the product is a disc brake pad in which a friction material is laminated and fixed on a back plate made of cast iron or steel, and the surface of the friction material is hit with the hammer head. apparatus.   The sound collecting unit according to any one of claims 1 to 3, wherein the sound collecting unit has a waveform analyzer connected to the sound collector, and the striking sound collected by the sound collector is analyzed by the waveform analyzer. The hitting sound inspection device described.   The hitting sound according to claim 4, wherein the waveform analysis device obtains an attenuation degree of the hitting sound collected by the sound collector, and compares the attenuation degree with a reference attenuation degree to detect an internal defect of the product. Inspection equipment.

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