Portable telephone set

#1. Field of the Invention

#The present invention relates to portable telephone sets, and more particularly to a portable telephone set suitable for a global system for mobile communication (GSM).

#Recently, it has been considered in Japan to employ, as a communication system using portable telephone sets, the GSM which has been employed in Europe. The GSM does not require registration of a telephone number for each portable telephone set. Each individual (subscriber) is assigned to a subscriber identity module in which information concerning the subscriber is stored. If the subscriber exchanges the old portable telephone set by a new one, the subscriber identity module is detached from the old telephone set and is then inserted into the new one. If the rent portable telephone set is used, the subscriber inserts the own subscriber identity module into the set. Thus, the new or rent portable telephone set can be used as the subscriber own portable telephone set.

#Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings, in which:

#FIGS. 1A and 1B are diagrams of a conventional portable telephone set;

#FIG. 2A is a partially-cutout plan view of a portable telephone set according to an embodiment of the present invention;

#FIGS. 2A and 2B are diagrams of a portable telephone set 30 which can be applied to the GSM according to an embodiment of the present invention. Further, FIG. 3 is an exploded perspective view of the portable telephone set 30. FIG. 4 is an enlarged perspective view taken along arrow III shown in FIG. 2B.

#The portable telephone set 30 has a front case 32 and a back case 34 between which a printed wiring board unit 36 is interposed. The whole case of the portable telephone set 30 includes the cases 32 and 34. The front case 32 is equipped with a key group sheet 31 on which a plurality of keys are arranged. The back case 34 is equipped with an antenna 37. The printed wiring board unit 36 is equipped with a liquid crystal unit 35. The front case 32, the rear case and the printed wiring board unit 36 are longitudinal in directions Y1 and Y2. A housing 51, which will be described in detail later, is attached to the printed wiring board unit 36. The portable telephone set 30 has a front surface facing in a direction Z1 and a back surface facing in a direction Z2.

#A plurality of keys 39 are arranged in a front surface 30a of the portable telephone set 30 so that the keys 39 occupy an area located in a direction Y2 with respect to the center in the longitudinal direction. A display window 40 of the liquid crystal unit 35 and an acoustic output part 41 formed of a speaker are provided in an area located in a direction Y1 with respect to the keys 39. An acoustic output part 42 formed of a microphone is provided in the area located in the direction Y2 with respect to the key