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Rectangular-shell, electrical connectors which are used in Roombas, are generally manufactured by Hirose Electric Company, Ltd. In-line contacts of two, three, and seven are used; and 2x2, 2x3, 2x6, and 2x8 contact arrays are also in use. Two pitch-sizes are used, 2-mm and 2.5-mm. When de-mating this basic shell-type, the worker will probably be able to safely do so with all of the low contact-count, small shell-size connectors -- by use of finger-nails, or small pry-bars -- so long as there is adequate free-space, and fulcrums. It is the 2x8, and one of the 2x6 connectors along the upper PWB-edge that may present some difficulty. There is also a cluster of five jacks on the PWB's front face, which are so close together that not much of anything will fit between them. It is for these few cases that use of a special connector de-mate tool is recommended. Two types are identified below.
The Dual In-line Package (DIP) extractor-tool is an old tool, having first come into use in the 1960s. It is still in use in 2006, therefore electronic-parts and equipment outlets still stock these old tools. They sell for about $5. The first illustration shows the tool alongside one of the DIPs it was built to pull out of an array of lead-sockets.
The particular tool shown in these illustrations is the AUGAT 114-1. We'll see, in a moment how nicely the tool's size works with the 16-contact (J10) Cover-pigtail connector; however, the tool also closes down well onto the 2-contact shell too.
Here, in this next view, we see the Augat tool being engaged with the plug-cap connected to J10. Notice how well the thin jaws of the tool fit between the jack and plug-cap.
The stock DIP-extractor tool will have jaws shaped like folded, flat-blade screwdriver tips -- fine for DIPs, but not quite what is needed for these Hirose connectors. If you have not already noticed the connectors have a keying-device at each end. The jack has open slots, running parallel to the mate / de-mate motions, and the plug-cap has ribs which fit those slots. Further, to prevent 180° flip-mating of the connector, Hirose offsets the keying system.
Typically the 2-mm-pitch connectors have their keys closer to the PWB than is the center of an end-face; while the 2.5-mm pitch connectors are inverse. The point of mentioning that is the tool must be modified to clear those keying ribs, and such modification is done by filing a narrow groove across each jaw. So, a wise person, doing that filing, may not want to file the grooves centered with respect to the jaws width, but rather offset them a little. Take a look at the next image, in which the fit-up of a notched jaw to the keying rib can be judged:
The tool is narrower than the connector width, so the notch may be close to the jaw's mid-point and be able to grip the connector without any interference from the PWB. If a different extractor model, say one with wider jaws, had been purchased, it could be prudent to offset the notches. In fact, that condition occurred in the home-made tool, to be discussed as the next topic.
Some people might not want to purchase a special tool for Roomba's connectors. However, de-mating the 16-contact connector by any means (except finger-nails, perhaps) that does not firmly grip the ends of the plug-cap while force is applied, is a threat to the health of the cable wires. Thus, as an effort to devise a de-mate tool from common tools or materials that might be found around many auto-garages, or home-shops, a rather crude device was formed from a free-tool which is commonly supplied with purchased house-paint (by thousands of southern California hardware and paint-stores). Here is a picture of the tool. One one end is a loop-type beer-bottle cap-lifter; while the opposite end has a handy 90° lip, that look just about right for hooking under one end of a Hirose connector.
The L-shaped ends of two paint-lid lifters were re-shaped, by grinding and filing them to reduce their widths and thickness, and were then notched to clear the keying ribs.
Four fender-washers were applied to the big-loops, a spacer was placed between the inner washers and a through-bolt with wing-nut clamped the loop-ends together, while also providing a reasonable grip on the plug-cap at the opposite end of the "tool". Here we see it fitted to P10, and ready to de-mate it:
The home-made tool works, but it is far from optimum. In fact, the title of this section says "limited application", and the reason is its jaws are still quite thick (compared to the Augat tool's jaws), and a bit of fiddling is required when shifting to smaller sized connectors. It needs a lot of clearance to neighboring hardware. For example, it will readily work on the 6-contact (wheel-system) connector appearing at lower right in the above image; but, it could not be applied to the similar connector (for the RHS-wheel) at the opposite end of the PWB (and off scene).
A final point to be recognized here is making a de-mate tool is not all that hard, if one can just find the right starting materials.
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