| 摘要 |
PROBLEM TO BE SOLVED: To easily and firmly adhere upper and lower cases together without deteriorating the performance of an electronic part housed therein. SOLUTION: An upper and lower case for battery pack 16, 17 are combined so as to mutually butt connecting surfaces 23a, 21 formed substantially on the whole circumference thereof. A projection 25 and receiving part 22 for welding are provided on the angle parts of the connecting surfaces 23a, 21. The upper case 16 is put on the lower case 17 containing a secondary battery, the part of the projection 25 is ultrasonically welded to temporarily fix the upper and lower cases 16, 17, and allowed to stand until the adhesive preliminarily applied to the connecting surfaces 23a, 31 entirely is hardened. Since substantially the whole circumference of the upper and lower cases 16, 17 is adhered by the adhesive, the adhesive strength is increased. Further, since they are temporarily fixed in the state where the connecting surfaces 23a, 21 are closely fitted to each other by ultrasonic welding, the upper and lower cases 16, 17 can be allowed to stand as they are without using a special fixing tool. |
