JPH026365Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rubber boot fixing device that is attached to an automobile axle or the like for waterproofing and dustproofing purposes. Conventionally, this type of boot is generally fixed to a member to be attached by wrapping a steel belt around its outer circumferential surface, and one method of fastening the steel belt is to insert the steel belt between the boot and the steel belt. A method has been proposed in which a boot fixing device equipped with a pressing jig is used to overlap both ends of the steel belt on the pressing jig, and the overlapping portion is irradiated with a laser beam to weld both ends of the steel belt. While using this laser device, the actual output may decrease due to fogging of the lens or mirror, etc.
Although welding defects may occur, the welding condition can only be inspected from the surface of the overlapping part at both ends of the steel belt, so it is difficult to determine whether the welding condition is good or bad, and the boot installation condition However, this method is difficult to apply to products where safety is important.

In order to solve this problem, the object of the present invention is to provide a boot fixing device that can accurately determine the welding state by using acoustic emission. A boot fixing device that wraps a steel belt around a surface and fixes it to a member to be attached, and includes a pressing jig that is inserted between the boot and the steel belt. In the device in which both ends are overlapped and the overlapping portion is irradiated with a laser beam to weld the ends, an acoustic stress detection element is provided in contact with the pressing jig, and an acoustic stress detection element is provided in contact with the pressing jig. The present invention is characterized in that it includes means for counting the number of peaks exceeding a predetermined amplitude of the acoustic emission wave and determining the quality of the welding condition from the magnitude of the counted number.

The present invention will be described below with reference to the illustrated embodiments.
Referring to FIG. 1, reference numeral 1 indicates a front axle of a front wheel drive vehicle, and the shaft 1 includes an intermediate shaft portion 2 and constant velocity joints 3 at both ends thereof, and each constant velocity joint 3 and the intermediate shaft portion A rubber boot 4 is attached between the two.

The boot 4 has the intermediate shaft portion 2 at one end thereof.
and the other end of the boot 4 are fixed to the intermediate shaft portion 2 and the constant velocity joint 3 by means of steel belts 5 which are fitted onto the constant velocity joint 3 and wound around the outer periphery of each of them. Since the fixation is performed in the same manner using the device of the present invention shown in FIG. 2, the procedure for fixing one end of the boot 4 to the intermediate shaft portion 2 will be described below.

First, as shown in FIG. 3, one end of the boot 4 is fitted to the boot fixing part 2a on the outer periphery of the intermediate shaft part 2, and then the pressing jig 6 provided in the present device, which is movable up and down and back and forth, is moved down. A pressing piece 6a protruding forward from the lower end of the jig 6 is pushed into a part of the outer peripheral surface of one end of the boot 4. Here, a clamp jig 7 is arranged around the fitting part of the boot 4 as shown in FIG.
In the unclamped state of the clamp jig 7, a steel belt 5 is placed between the inner peripheral surface of the clamp jig 7 and the outer peripheral surface of the boot 4.
As shown in FIG. 5, the steel belt 5 is conveyed from a belt roll 9 by two pairs of conveying rollers 10 and inserted into the gap 8, and the steel belt 5 is inserted into the gap 8. When the tip of the belt 5 goes around the gap 8 and slightly passes over the pressing piece 6a, the conveyance of the steel belt 5 is stopped,
Next, as shown in FIG. 6, the clamp jig 7 is operated to clamp the steel belt 5 wound around the outer circumferential surface of the boot 4 from the outside against the outer circumferential surface of the boot 4. Next, as shown in FIG. 7, a beam guide jig 1 is disposed above the pressing piece 6a so as to be vertically movable and has a laser beam transmission path 11a in the vertical direction.
1 is moved downward, the steel belt 5 is cut by the cutter part 11b formed on one side of the lower end of the jig 11, and both ends of the steel belt 5 are superimposed on the pressing piece 6a by the lower surface of the jig 11. Then, as shown in FIG.
The steel belt 5 is guided through the steel belt 5 to the overlapped portion at both ends, and the ends are welded together. The heat generated in the overlapping portion during this welding is prevented from propagating to the boot 4 by the pressing jig 6, and the boot 4 will not be damaged by the heat.

After welding is completed, the beam guide jig 11 is moved upward, the clamp jig 7 is unclamped, and the press jig 6 is moved back to pull out the press piece 6a. The part of the boot 4 that had been held is restored by elasticity, and its outer circumferential surface is brought into close contact with the inner circumferential surface of the steel belt 5, resulting in the boot fixed state shown in FIG.

According to the present invention, an acoustic emission detection element 13 is provided in contact with the pressing jig 6 as shown in FIG. The jig 6 is compressed by energy propagation to the pressing jig 6 via
Acoustic emission waves (hereinafter referred to as AE waves) generated from the constituent materials of the element 13
By detecting this and guiding it to the analyzer 15 via the amplifier 14 and analyzing it, it is possible to determine whether the welding condition is good or bad.

In other words, the amplitude of the AE wave increases as welding progresses, and when the number of peaks of the AE wave exceeding a certain amplitude is counted, the welding condition becomes better as the number of counts increases, as shown in Figure 9. The lower limit N of the AE wave count at which the welding condition is good, that is, the tensile strength satisfies the standard value, is experimentally determined and measured by comparing this value N with the actual measured value. When the value falls below the lower limit value N, an alarm can be issued to notify that the welding condition has become poor.

As described above, according to the present invention, the acoustic emission detection element is provided in contact with the pressing jig inserted between the boot and the steel belt, and is polymerized on the pressing jig and beam-welded. The quality of the welding at both ends of the steel belt can be determined based on the AE waves detected by the element, which has the effect of improving the reliability of product quality assurance.

[Brief explanation of the drawing]

Fig. 1 is a side view of an example of a product with a boot attached, Fig. 2 is a schematic side view of the proposed device, and Fig. 3 is a cutaway side view of the main part showing the pressing jig in the boot. Fig. 4 is a cross-sectional view taken along the - line in Fig. 3;
5 to 8 are cross-sectional views illustrating the winding and welding procedure of the steel belt, and FIG. 9 is a graph showing the relationship between the AE wave count and the tensile strength of the welded part. 4...Boots, 5...Steel belt, 6...
Pressing jig, 13...acoustic emission detection element.

Claims (1)

[Scope of utility model registration request] A boot fixing device for fixing a waterproof and dustproof rubber boot to a member to be attached by winding a steel belt around its outer peripheral surface, the boot fixing device comprising a pressing jig inserted between the boot and the steel belt, Both ends of the steel belt are overlapped on the pressing jig, and the overlapping portion is irradiated with a laser beam to weld the two ends, and an acoustic emitter is detected by contacting the pressing jig. In addition to providing an element, a means for counting the number of peaks exceeding a predetermined amplitude of an acoustic emission wave detected by the element and determining the quality of the welding condition from the magnitude of this count is provided. Features a boot fixing device.