Portable calculator

• US 4,002,892 A
• Filed: 09/16/1974
• Issued: 01/11/1977
• Est. Priority Date: 09/15/1973
• Status: Expired due to Term

• Current Assignee: Adolf H. Zielinski
• Original Assignee: Adolf H. Zielinski
• Inventors: Zielinski, Adolf H.
• Primary Examiner(s): Dildine, Jr., R. Stephen
• Application Number:
  US05/506,196
• Time in Patent Office: 848 Days
• Field of Search: 200/292, 200/5 A, 200/5 R, 200/159 B, 235/145 R, 235/156, 307/150, 307/154, 317/101 A, 317/101 B, 317/101 C, 317/99, 317/101 D, 317/101 R, 317/101 DH, 325/492, 339/17 LC, 339/17 M
• US Class Current: 361/679.09
• CPC Class Codes: G06F 15/02 manually operated with input through keyboard and computation using a built-in program, e.g. pocket calculators
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/785 characterised by the material of the contacts, e.g. conductive polymers
• CPC Class Codes: H01H 13/807 characterised by the spatial arrangement of the contact sites, e.g. superimposed sites
• CPC Class Codes: H01H 2201/026 non precious
• CPC Class Codes: H01H 2203/02 Interspersed fingers
• CPC Class Codes: H01H 2207/022 Plug
• CPC Class Codes: H01H 2209/016 Protection layer, e.g. for legend, anti-scratch
• CPC Class Codes: H01H 2217/016 Pressure reduction membrane; Spreader layer
• CPC Class Codes: H01H 2221/01 also rotatable
• CPC Class Codes: H01H 2221/014 Slide selector
• CPC Class Codes: H01H 2221/05 Force concentrator; Actuating dimple
• CPC Class Codes: H01H 2223/034 Bezel
• CPC Class Codes: H01H 2225/002 superimposed
• CPC Class Codes: H01H 2227/004 Membrane
• CPC Class Codes: H01H 2231/002 Calculator, computer
• CPC Class Codes: H01H 2239/01 combined with other elements on the same substrate
• CPC Class Codes: H01H 2239/016 combined with start switch, discrete keyboard
• CPC Class Codes: Y10S 439/923 Separation or disconnection aid

Abstract

A portable electronic calculator is provided with a housing carrying a first printed circuit board having the operating parts mounted thereon, i.e., keyboard, electronic arithmetic unit, and multi-digit display unit. The housing is of rectangular outline and of shallow height, and is provided at one end with a receptacle communicating with the first printed circuit board and opening at the end of the housing. An electrical supply unit is mounted on a second printed circuit board which slides into said receptacle, said two printed circuit boards having plug-and-socket connection means therebetween for automatically making and breaking connections when said second printed circuit board and electrical supply unit are inserted into or removed from said receptacle.

Claims

1. A portable electronic calculator comprising a housing of substantially rectangular outline having a length greater than its width and being of shallow height relative to its width, said housing having an end opening receptacle at one end thereof surrounded by top, bottom and side walls, a first printed circuit board retained in said housing inwardly of said receptacle and having connected thereto a keyboard, an electronic arithmetic unit, and a multi-digit display unit, said housing having appropriate areas for visual access to said display unit and for manual access to said keyboard, a second printed circuit board, and electrical supply unit on said second printed circuit board, said electrical supply unit and said second printed circuit board being movable into and out of said receptacle and positioned thereon by said walls, and plug- and-socket connection means between said first and second printed circuit boards and automatically engaging and disengaging upon insertion and withdrawal of said second printed circuit board and electrical supply unit said second printed circuit board and said electrical supply unit being housed in a rectangular block fitting within said receptacle.

2. A calculator as set forth in claim 1 and further including means providing a notch in a wall of the calculator housing and a projection on said block to key the position of said block in said calcultor housing.

3. A calculator as set forth in claim 1, wherein the first and second printed circuit boards are coplanar when the second printed circuit board is in said receptacle.