# Patent

## Title
Method of forming a shell and coil heat exchanger

## Abstract

This application is a division of Ser. No. 454,213 filed Dec. 21, 1989, now abandoned.

## Background
This invention relates to an electrical connector modularly arrayed as the electrical connector in U.S. application Ser. No. 432,429 filed Nov. 6, 1989, U.S. Pat. No. 4,981,446 and also assigned to The Boeing Company, however further configured to include retention clips for manual or automatic assembly of the electrical contacts in the connector as hereinafter described.

A preferred embodiment of the present invention utilizes an electrical connector having a connector cable clamp (backshell) and grommet assembly which is loaded with electrical contacts using a pneumatic contact loader which is then assembled onto the connector shell.

It is an object of the present invention to provide a method and apparatus enabling automation and robotic fabrication and assembly of electrical/electronic wire bundle assemblies.

A further object of the present invention includes a circular, modular connector assembly characterized by elimination of the insertion tool which results in a making of an improved and more reliable environment resisting connector.

FIG. 1 is a cross sectional view illustrative of the assembly of the present modular connector, and included in the illustration is a connector cable clamp or backshell further showing a grommet assembly being loaded with electrical contacts using a pneumatic contact loader which is subsequently assembled onto the connector shell;

FIG. 2 is a side elevational view of the grommet assembly;

FIG. 3 is an end view (face) of the connector shell where the master keyway on the receptacle face is highlighted;

FIG. 4 is a cross section of the pneumatic loader illustrating the electrical contacts being pulled into the retention clip; and,

FIG. 5 is a cross sectional schematic layout of the pneumatic contact loader.

The new electrical, circular, environment resisting connector utilizes a modular construction consisting of a connector shell 1 and a grommet assembly 2. Included in the illustration in FIG. 1 is a connector cable clamp or backshell 16 and a wired grommet assembly 2 to be loaded onto connector shell 1. The construction of the connector shell is identical to the existing Mil-C-26500, Mil-C-38999, Mil-C-83723 and Mil-C-5015 (as required) with the following modifications: key 3 is added. The alignment key 3 is located at the rear end of the connector shell 1 and positioned at 0 degree or 12 O'Clock (same polarization as the connector master keyway 4 receptacle as shown in FIG. 3 or key (plug-not shown).

The grommet assembly 2 (see FIGS. 1 and 2) consists of a grommet 5 with sealing webs 6 designed to have a seal range of 0.035-0.090 inch for #20 size contact which eliminates build-up sleeves. Grommet assembly 2 further includes dielectric 7 with retention clips 8, interfacial seal 9 designed to seal the individual holes within the grommet and a pressure ring 10 with an O-ring 11 for environmental seal and a 360 degree accessory teeth 12 and a keyway 13.

The assembly process (automation or manual) is described below: 15 onto grommet 5 (manual assembly) or use a gripper (not shown) to push contact(s) 15 onto grommet 5 (robotic assembly).

IMPORTANT: This process enables contact(s) end 17 to extend beyond the grommet assembly 2 (approximately 1/16 to 1/4 inch). robotic operation) to insert contact(s) into retention clip(s) 8.

IMPORTANT: This process also provides the Operator with a tactile and visual verification that the contacts 16 are correctly seated in the retention clips 8.

Pneumatic Contact Loader 18 (see FIG. 5) consists of: an air sensor 19, air regulator 20, air cylinder 21 and a collet 22. An air cylinder 21 and collet 22 are housed in a cylindrical shape tube 23. An exhaust (pin) hole 24 located at the tip of the cylindrical tube 23 serves as an on-off switch for the sensor 19. The amount of air blowing thru the exhaust hole 24 is set by the regulator 20 at about 15 psi. Plugging the exhaust hole 24 with the operator's thumb turns off the sensor 19 thus allowing the line pressure to flow and drive the air cylinder 21 which in turn activates the collet 22 to close and grab the electrical contact end 17. The collet 21 will release the contact 15 when the load (force) reaches 15 pounds (same requirement in installing #20 size contact). connector shell 1 and push grommet assembly 2 inside the connector shell 1.

To remove wire(s):

To move and/or replace wire(s): 8.

## Claims

1. The method of assembling an electrical connector comprising the steps of: wires (14); by pushing electrical contacts (15) onto a grommet (5); pneumatic contact loader (18); of the connector shell (1) and pushing grommet assembly (2) inside said connector shell (1), and then,