| 摘要 |
<p>1,069,120. Loudspeakers. PHILIPS ELECTRICAL & ASSOCIATED INDUSTRIES Ltd. Sept. 1, 1964 [Sept. 2, 1963], No. 35736/64. Heading H4J. In a moving coil loudspeaker, a soft magnetic plate 13 and pot 12 are held rigidly together by one or more indentations 10 formed in a generally frusto-conical frame 16. Conical part (12<SP>1</SP>), Fig. 2 (not shown), has an apical angle (α) a little smaller than the apical angle (#) of the frame part (16<SP>1</SP>) to assist in providing a rigid assembly. In manufacture, the frame 16 is placed on a press and the pot 12 and plate 13 are then placed in position. Grooves or other indentations 10 are then made with four or six different balls. The loudspeaker includes a central magnet 13 which is secured by adhesive or a brass centring ring either before the formation of the indentations or subsequently. The frame 16 is of aluminium coated with plastics material or is of extruded plastics.</p> |
