| 摘要 |
1,168,535. Keyboards for printers. OAK ELECTRO/NETICS CORP. 14 April, 1967 [15 April, 1966], No. 17343/67. Heading B6F. [Also in Divisions E2 and H1] A push-button assembly for a computer control panel, for example, comprises several rows R of buttons 10 wherein strips 26 slidable in a channel member 28 prevent more than one button 10 in a row being fully depressed at a time, and associated with each row R is a bar 36 which is displaced when any key in the row is depressed and strips 46 (similar to strips 26), slidable in a transverse channel member 48, prevent displacement of more than one bar 36 at a time; thus only one button in the whole assembly can be fully depressed at a time. The strips 26 (and 46) have stepped cam surfaces at their ends (Figs. 6 and 7, not shown) overlapping by approximately the thickness of the button shanks 30 so that the total displacement when a button is depressed is twice the thickness of shank 30, thus rendering manufacturing tolerances less critical. The bars 36 are carried by pivot-pins 37 on bell-cranks 34 at each end such that a bar 36 suffers similar displacement whichever button 10 in the row is depressed. Arms 44 connected to the bellcranks 34 at one end of each bar 36 displace the interlock sliders 46 when a bar is actuated. The buttons are also provided with a pivoted latch bar 52 engaging notches (66, Fig. 5, not shown), in shanks 30 to hold a button depressed until released by the initial movement of another button. Switch contacts (not described) are operated by the buttons. |
