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General Electric and Academy plugs
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In the late 1940s George B. Benander and Gustaf R. Lawson, electrical engineers at General Electric Company, developed a method for wiring non-grounding plugs without using any tools.
See image nos 1 - 4.
About the same time Arthur Greenbaum was working on a comparable project at Academy Electrical Products Corporation. See image nos 5 - 13.

General Electric plug with automatic wiring device, 1
General Electric plug with automatic wiring device, 2
General Electric plug with automatic wiring device, 3

1

General Electric non-grounding plug. Rating is not indicated but 10A - 125V is likely. Tools are not needed to wire the plug with a flat two-wire cord. The method is described below.   {WN}

2 - 4

The principle of automatic wiring is invented by George B. Benander and Gustaf Lawson; see General Electric US patent 2609415.
The same principle has also been applied to receptacles with multiple outlets (US patent 2655639).

The method, shown in image 4, is based on figures 2 and 3 in patent 2609415. Numbers that indicated different parts of the plug have been deleted; colors are added to highlight essential parts.
  Wiring procedure:
(1) push a flat, 2-wire cord as far as possible into the plug (see image 2). Patent fig. 2 shows the cam in upright position. It is not necessary to rotate the cam beforehand. Cam in down position will be pushed upright by the cord.
(2) after being fully inserted the cord will be juxtaposed but not in electrical contact with the two prongs (red and orange triangles).
(3) rotate cam down. The prongs will pierce the cord insulation and make contact with the conductor wires (see image of cord cross section).
(4) the cam in down position (patent fig. 3) pushes the cord in a kinked position, which offers sufficient strain relief to fix the cord.

Plug right in image 2 shows an additional safety feature (green arrow).
At the end of cord the two wires are separated and pushed in opposite directions. This eliminates any chance of a short circuit between the ends, which could happen if the insulation is pushed back from the conductor wires during insertion of the cord.






General Electric plug with automatic wiring device, scheme

Benander's invention was advertised as Quick Clamp Plug.

 


Academy automatic 3-way cube

Academy automatic 3-way cube

Academy automatic 3-way cube

Academy automatic 3-way cube, detail


5 - 8 Academy automatic 3-way cube, rated at 15A - 125V.
1: topview.   2: cube with three non-grounding plugs. The brown wire is attached to mains by a wall plug (not shown). 
3, 4: inside views; both sharp brass needles (green arrows) punch the flat wire insulation when the two plug halves are closed firmly. See instruction card for details

 

Mid 1990s Academy Electrical Products Corp. became a brand of Eagle Electric Manufacturing Company, also based in New York. Plugs shown below have been marketed by Eagle as easy to install replacement plugs,  "just snap on! no tools needed".
Both Eagle plugs, bought in the US, have been donated by Roland Angenent.

Eagle Academy Super Plug
Eagle Academy Super Plug

9, 10

Academy® Super PlugTM rated at 10A - 125V.   {RA}

Plug was patented by Academy Electrical Products in 1991.
The US Patent Office assigned the patent to Eagle Electric Mfg. Co. in 1995.

Dissolution of Academy Electrical Products was proclaimed on May 3, 2000.



Eagle Academy Super Plug, details

11

The Academy Super Plug consists of two halves. Brass plug blades of the left half
have sharp points (red arrows) for penetrating the insulation of the cord that has
pushed in under latch spring of the other half.
Contact between blades and wires is made when the the two halves are pressed together (green arrow and dottes green line).
The procedure is shown also in steps 1, 2 and 3 on the Eagle instruction card right.
Eagle Academy Super Plug, card

Eagle Easy Install plug

Eagle Easy Install plug, details

12

 
13
Academy® Easy Install non grounding plug, made by Eagle Electric. Rating: 10A - 125V. The cord snap in method differs from the procedure used in the other two Academy plugs. In contrast to the Academy Super Plug (image nos. 9-11), a patent re-assignment to Eagle Electric was not necessary, because the original Academy Electrical Products patent expired already in 1985.   {RA}

How to wire an Easy Install plug.
(1) press blades together to free the blade unit; (2) open both blades; (3) push the two stranded wire all the way in; (4) press the blades fully back to their parallel position; (5) push back the blade unit into the cap; (6) the patent drawing shows that the barb (red arrow) of each blade has penetrated a wire insulation and realizes contact between wire and blade; (6 ,7) the drawing shows also that pushing the blade unit into the cap forces the cord into a zigzag shape. A pulling force exerted on the cord will not result in breaking off contact between blade and wire. Note that an eccentric cord entry is essential to establish a cord zigzag.


Academy ... Eagle ... Cooper

Eagle Electric Manufacturing was acquired by Cooper Industries in 2000 and became part of Cooper Wiring Devices. The 2018 Cooper catalog shows that Academy® Plugs are still available; find Super Plug and Easy Install Plug on page I-22. Cooper offers two versions of both plugs: a classic model with two 6.4 mm wide blades and a polarized model that has one 8.1 mm blade.
Academy® connector plugs are shown on page I-23. The Cube model has been changed slightly; the position of the three outlets differs.
Greenbaum's inventions have survived the changes in company management.
Since Eagle's patent on Easy Install plugs has been expired some other manufacturers offer the plug also.
Patents

Images 1-4
US2609415   Electric connector.
Inventors: George B. Benander and Gustaf R. Lawson. Assignee: General Electric Co., New York,
Application: Augus,t 24 1949. Patented: September  2, 1952.  Expiration date: September 2, 1969. 

Related to images 1-4
US2655639   Electrial connector with insulation piercing means contacting the conductors of electric cords.
Inventors: George B. Benander and Gustaf R. Lawson. Assignee: General Electric Co., New York,
Application: December 29, 1951. Patented: October  13, 1953.  Expiration date: October 13, 1970.

Images 5-8
US2704832   Multiple Cord Plug Receptacle.
Inventor: Arthur Greenbaum. Assignee: Academy Electrical Products Corp. New York, N.Y.
Application: March 23, 1954.  Patented: March 22, 1955.  Expiration date Mar. 22, 1972.

Images 9-11
US5041013   Electrical Connector.
Inventor: Arthur Greenbaum. Assignee Academy Electrical Corporation, Scarsdale, N.Y.*
Application: September 14, 1990.  Patented: Augustus 20, 1991.  Expiration date: Aug. 20, 2008.
* Assigned to Eagle Electric Manufacturing Company, Inc.. New York on August 31, 1995

Images 12-13
US3408616   Insulation Piercing Electrical Connectors.
Inventor: Arthur Greenbaum. Assignee: Academy Electrical Products Corp. Scarsdale, N.Y.
Application: April 21, 1966.  Patented: October 29, 1968.  Expiration date: Oct. 29, 1985.

 


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