JP3599943B2 - Brake lining inspection device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an inspection of a brake lining used for a vehicle brake, and more particularly, to a device for inspecting a crack or an internal swelling in an arc-shaped brake lining used for a drum brake.
[0002]
[Prior art]
The brake lining is made of a material obtained by mixing a fibrous material, a filler and a binder. As the fiber material, organic fibers such as cellulose pulp and aramid, metal chips such as chip-shaped metal pieces or steel wool, and inorganic fibers such as rock wool are used. As the filler, barium sulfate, calcium carbonate, graphite or the like is used. The binder binds a fiber material or a filler, and is made of a thermosetting resin such as a phenol resin and a rubber.
These raw materials are mixed at a designed ratio, then weighed to a predetermined weight, placed in a mold, and pressurized and heated to form a brake lining.
[0003]
By the way, in the above-mentioned forming process, gas is generated when the raw material is heated and melted. In principle, most of this gas is vented and released to the outside. In some cases, however, the gas is insufficiently vented and a part of the gas is trapped inside. The residual gas may cause swelling (cavity) inside the completed brake lining, or cracks may occur due to the residual gas and various conditions such as cooling conditions. If there is a crack, the strength decreases, and if there is swelling, a cavity appears and the frictional force decreases while the brake lining is used. Therefore, it is very important to inspect the formed brake lining for cracks and blisters.
In response to such requests, hitherto, cracks and swelling have been hit with a hammer, and the difference in hitting sound has been judged by ear or visually inspected on the surface.
[0004]
[Problems to be solved by the invention]
However, in such a sensory test relying on human senses, (1) the influence of the skill of the measurer is large, the stability of the measurement accuracy is lacking, (2) the noise due to the tapping noise is large, (3) especially, In the case of the brake lining of a large vehicle, there is a problem that a work becomes heavy and a burden on an operator is large.
[0005]
SUMMARY OF THE INVENTION The present invention has been made to solve these problems, and a first object of the present invention is to provide a brake lining inspection apparatus which does not require skill and eliminates hitting sounds. It is a second object of the present invention to provide a brake lining inspection device capable of reducing the burden on an operator.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a brake lining inspection apparatus according to the present invention includes a feed member that conveys a brake lining along an arc-shaped guide surface having substantially the same curvature as the brake lining, and a feed member that is conveyed along the guide surface. And an ultrasonic probe which is disposed so as to be in contact with both sides of the brake lining.
[0007]
Further, the ultrasonic probe has a rotating roller that comes into contact with a brake lining, and at least one of the ultrasonic probes is spring-biased so as to be able to advance and retreat with respect to the brake lining. It is desirable to provide an entrance detector for detecting that the leading end of the lining has reached the measurement position and an exit detector for detecting that the rear end of the brake lining has passed the measurement position.
[0008]
The feed member may be configured to include a rotating disk and a feed claw provided on the disk.
Further, it is possible to provide a carry-in device for sending the ultrasonic wave to 140 to 170 Khz or for sending an untested brake lining to the feed member, and a carry-out device for discharging the tested brake lining.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The present invention applies ultrasonic internal flaw detection to the inspection of cracks and swelling of brake linings. Conventionally, such an ultrasonic internal flaw detection method has never been used for inspection of a brake lining. Therefore, even if the ultrasonic flaw detection method is applied, whether the transmission method or the reflection method should be adopted, the number of probes is one or two, and the direct method is the water immersion method, etc. Then, the direct method was adopted as the transmission method.
[0010]
1 to 3 are views showing the configuration of a brake lining inspection apparatus using the ultrasonic flaw detection method of the present invention. FIG. 1 is a top view, FIG. 2 is a view from A in FIG. 1, and FIG. FIG. FIG. 4 is an enlarged plan view of a main part of the inspection device, and FIG. 5 is a diagram illustrating a case where the curvature radii of the brake linings are different. With reference to these drawings, first, the configuration and operation of the main part of the present invention will be described, and then the configuration and operation of the peripheral portion will be described.
[0011]
The brake lining 1 shown by a virtual line in the above-mentioned figure is used for a drum brake and has an arc-shaped surface which is a part of a cylinder. The brake lining 1 is a material in which the binder reacts under pressure and heat in the mold as described above, and is cured. After being taken out of the mold, the brake lining 1 may be polished as necessary. Has undergone various finishing processes.
[0012]
The main components of the inspection device include the feed member 2, the ultrasonic probes 4 and 5, and the detectors 6 and 7.
[0013]
The feed member 2 is provided on the upper surface of the frame of the inspection apparatus, and has a shape in which two disks are vertically stacked at an interval, has a pulley 2a in a lower frame, and has a motor also provided in the frame. 8 is connected to a pulley 8a by a belt and is rotatable. The guide surface 3 is a trajectory along which the brake lining 1 moves, and overlaps a considerable portion of the outer peripheral surface of the disk.
[0014]
The feed member 2 has a feed claw 2b formed in a protruding shape on the outer periphery thereof. When the feed member 2 rotates, the feed claw 2b hits the rear end face of the brake lining 1 so that the brake lining 1 is brought into contact with the arcuate guide surface 3. Move along.
[0015]
One of the ultrasonic probes 4 and 5 is a transmitter and the other is a receiver, and the ultrasonic wave emitted from the transmitter side is transmitted through the brake lining 1 as a work and received by the receiver. Is what you do. This method utilizes the fact that when there is a defect such as a crack or a cavity in the work, the energy of the ultrasonic wave received on the receiver side is scattered and reduced.
[0016]
The frequency of the ultrasonic wave in ultrasonic inspection differs depending on the material of the work. On the other hand, the material of the brake lining to be the work also differs depending on the type of the vehicle and is not constant. However, it is complicated to set the frequency every time the material of the brake lining to be inspected changes. For this reason, various studies were conducted on what frequency is most efficient. As a result, within the range of 140 to 170 Khz, it was found that ultrasonic waves could be transmitted through brake linings of most commonly used materials, and flaw detection inspection was possible.
[0017]
These ultrasonic probes 4 and 5 have rotating rollers 4a and 5a at their contact portions with the work, and the spring linings 4b and 5b provided inside the ultrasonic probes 4 and 5 indicate the arrow of FIG. It is a configuration that can advance and retreat in the direction. Therefore, even when inspecting the brake linings 1 having different shapes (radius of curvature), the ultrasonic probes 4 and 5 can always maintain the contact state with the brake linings following the change in the shape of the work. Has become. Further, the outer ultrasonic probe 5 can be moved toward the center of the feed member by rotating the handle of the advance / retreat mechanism 9, and the distance between the outer ultrasonic probe 5 and the inner ultrasonic probe 4 can be adjusted.
[0018]
This following state will be described with reference to FIG. FIG. 5A shows a case where the curvature radius of the brake lining 1 is smaller than the curvature of the guide surface 3. In this case, since both ends 1a of the brake lining entering the ultrasonic probes 4 and 5 are on the guide surface 3, there is no problem that the tip enters between the ultrasonic probes 4 and 5 indicated by the imaginary line. . However, the central portion 1b of the brake lining 1 is separated from the guide surface 3 by S1. Then, with the movement of the brake lining 1, the ultrasonic probes 4, 5 gradually move in the direction of the arrow shown by the spring means 4b, 5b, and follow the outer shape of the work. When the ultrasonic probes 4 and 5 move inward beyond the position shown by the solid line (the center of the brake lining), they return to the normal state (standby state) when the rear end of the brake lining 1 passes.
[0019]
FIG. 5B shows a case where the radius of curvature of the brake lining 1 is larger than the radius of curvature of the guide surface 3. In this case, if the brake lining 1 is fixed to the guide surface 3, both ends 1a, 1a are separated from the guide surface 3 by S2, and the central portion 1b comes into contact with the guide surface 3. Therefore, when both ends are sandwiched between the ultrasonic probes 4 and 5, the rotating rollers 4a and 5a of the ultrasonic probes 4 and 5 rotate and move outward and follow as shown by arrows. Will be. Thereafter, with the movement of the brake lining 1, the ultrasonic probes 4 and 5 gradually move inward by the spring means 4b and 5b to reach the center. Thereafter, it moves outward again, and returns to the normal state after the rear end comes out.
[0020]
If the brake lining 1 is not firmly fixed to the guide surface 3, the brake lining 1 may follow the guide surface 3 between the ultrasonic probes 4 and 5. However, in any case, it is still desirable that at least one of the ultrasonic probes 4 and 5 is spring-biased.
When the thickness of the brake lining 1 changes, the distance between the ultrasonic probes 4 and 5 is adjusted by turning the handle of the advance / retreat mechanism 9.
[0021]
The entrance detector 6 and the exit detector 7 irradiate light such as infrared rays from one side and receive light on the other side. When the brake lining 1 is sent in and the infrared rays of the entrance detector 6 are cut off, the leading end of the work is detected. Is determined to have reached the measurement position, the exit detector 7 is unblocked, and when the infrared light is transmitted, it can be detected that the workpiece has left the measurement position.
[0022]
The entrance detector 6 and the exit detector 7 operate in conjunction with the ultrasonic probes 4 and 5, and when the entrance detector 6 detects the tip of the workpiece, the ultrasonic probes 4 and 5 start ultrasonic flaw detection. Then, when the exit detector 7 detects the passage of the rear end of the work, the flaw detection by the ultrasonic probes 4 and 5 ends.
[0023]
The above is the main configuration of the inspection apparatus of the present invention, but the configuration and operation of the peripheral parts other than these will be described below.
Reference numeral 10 denotes a carry-in device for supplying the brake lining 1 to the inspection device of the present invention. The brake lining 1 is carried in a state of being laid down on the carrying-in device 10 and is mounted on two round bars provided in parallel with the work receiving portion 11 of the inspection device.
[0024]
The work receiving section 11 is provided with a first cylinder 11a and a second cylinder 11b. When the rod of the first cylinder 11a retracts in the direction of arrow a, the work receiving portion 11 rotates in the direction indicated by arrow b about the shaft 11c, and rotates the brake lining 1 by 90 ° to be in an upright state. Then, the rod of the second cylinder 11 b projects in the direction of arrow c, and presses the brake lining 1 against the guide surface 3 of the feed member 2.
[0025]
Above the feed member 2, a support member 12 is provided. The support member 12 has a cylindrical shape, and is fixed above the feed member 2 with the edge cut from the feed member 2. As shown in FIG. 2, the height of the brake lining 1 is considerably higher than the height of the feed member 2. For this reason, there is a concern that the brake lining 1 during the movement may not fall down. Further, there is a possibility that the brake lining 1 may fall outward, and therefore, some pressing members 20 are provided outside.
[0026]
The brake lining 1 is sent from the carry-in device 10 to the inspection device along the arrow e, moves the guide surface 3 in the direction of the arrow d, undergoes ultrasonic inspection, and is judged to be good without cracks or swelling. Then, it is discharged in the direction of arrow f by a solenoid (not shown) provided in the feed member 2 and discharged by the unloading device 13 to the outside of the device.
[0027]
Reference numeral 14 denotes a defective work removing member. This is a shape in which an arc-shaped portion 14b is added to the tip of a substantially triangular plate 14a, and the arc-shaped portion 14b enters between two discs of the feed member 2, and its outer peripheral surface is formed by the outer periphery of the feed member 2. Surface, that is, the guide surface 3. The side surface of the plate 14a is also a part of the guide surface 3. The work in which cracks and swelling were found by ultrasonic flaw detection pass through the unloading device 13 without the operation of the solenoid, and are separated from the feed member 2 by the guide surface 3 of the triangular plate 14a of the defective work elimination member 14, The defective product is discharged in the direction of arrow g by the defective discharge device 15.
[0028]
In the above embodiment, the feed member 2 and the feed claw 2b rotate integrally, but the feed member and the feed claw are separately formed, the disk of the feed member is fixed, and only the feed claw is used. The brake lining may be sent by rotating and moving along the feed member. Further, although the case where only one pair of the ultrasonic probes 4 and 5 is shown, it is obvious that a plurality of pairs may be provided.
[0029]
【The invention's effect】
As described above, the inspection apparatus of the present invention includes a feed member that conveys a brake lining along an arc-shaped guide surface having substantially the same curvature as the brake lining, and a brake lining conveyed along the guide surface. The ultrasonic probe is arranged so as to be in contact with the surface of the brake lining, so that cracks and swelling of the brake lining after molding can be inspected by ultrasonic waves. Regardless, it can be inspected accurately and easily.
[0030]
If the ultrasonic probe has a rotating roller that comes into contact with the brake lining, and at least one of the ultrasonic probes is spring-biased so as to be able to advance and retreat with respect to the brake lining, the brake lining Even if the shape changes, the inspection can be performed following the shape.
[0031]
If there is an entrance detector that detects when the tip of the brake lining has reached the measurement position and an exit detector that detects when the rear end of the brake lining has passed the measurement position, the presence of the workpiece can be detected by both detectors Can be checked and inspection can be performed, inspection can be performed reliably, and automation can be performed.
[0032]
If the feed member has a rotating disk and a feed claw provided on the disk, the radius of curvature of the disk can be made to substantially match the radius of curvature of the brake lining, and It is possible to easily follow the tentacle to the brake lining.
If the ultrasonic wave is 140 to 170 Khz, measurement is possible even if the raw material of the brake lining changes variously.
[0033]
If a configuration is provided in which a carry-in device for feeding the uninspected brake lining to the feed member and an unloading device for discharging the inspected brake lining are used, it is not necessary to carry the work manually, and labor can be saved. Further, the burden on the operator can be reduced.
[Brief description of the drawings]
FIG. 1 is a plan view showing a configuration of a brake lining inspection device of the present invention.
FIG. 2 is a view as seen from A in FIG. 1;
FIG. 3 is a view seen from B in FIG. 1;
FIG. 4 is an enlarged view of a main part of the brake lining of the present invention.
5A and 5B are diagrams showing a state in which the ultrasonic probe follows the brake lining, where FIG. 5A shows a case where the radius of curvature of the brake lining is smaller than the curvature of the guide surface, and FIG. Shows a case where the radius of curvature is large.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 brake lining 2 feed member 2 b feed claw 3 guide surface 4, 5 ultrasonic probe 4 a, 5 a rotating rollers 4 b, 5 b spring means 6 inlet detector 7 outlet detector 10 carry-in device 13 carry-out device

Claims (6)

A feed member that conveys the brake lining along an arcuate guide surface having substantially the same curvature as the curvature thereof, and an ultrasonic wave that is disposed to face both surfaces of the brake lining conveyed along the guide surface so as to contact both surfaces thereof An inspection device for a brake lining, comprising: a probe. The said ultrasonic probe has a rotating roller which contacts a brake lining, and at least one ultrasonic probe is spring-biased so that advance / retreat with respect to a brake lining is possible. The inspection device for a brake lining according to claim 1. An entrance detector for detecting that the leading end of the brake lining has reached the measurement position, and an exit detector for detecting that the rear end of the brake lining has passed the measurement position. 2. The brake lining inspection device according to 2. The brake lining inspection apparatus according to any one of claims 1 to 3, wherein the feed member has a rotating disk and a feed claw provided on the disk. The inspection device for a brake lining according to any one of claims 1 to 4, wherein the ultrasonic waves are 140 to 170 Khz. The inspection device for a brake lining according to any one of claims 1 to 5, further comprising a carry-in device for feeding the uninspected brake lining to the feed member, and a carry-out device for discharging the inspected brake lining. .

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