OP

Quoted from TimMe:

Yes, I think that may be the only patent attributed directly to Dave Gottlieb other than a couple of game design patents. I read somewhere that he was proud of that patent. If I remember correctly, he had the idea of forming the socket position with a fold-back metal flap at the bottom where the solder tab was. Closing the bottom of the socket position prevented solder from wicking up into the socket cavity, which would spoil a connector and cause delays on the production line.
Since it doesn't look like Howard B. Jones ever patented their series 1400 connector, there was nothing to stop anyone from copying it. Gottlieb and Bally started making their own version of the connector, and Williams went in another direction with their own flat-blade connector for a while. But eventually it looks like Gottlieb, at least, started sub-contracting this part out to one or more suppliers again. This would have been in the 1960s, after the Howard B Jones company was long gone.
It's also interesting to note that while the form factor of the Gottlieb socket position solved the solder wicking problem, the version shown in the patent drawing actually had a design flaw that caused some trouble. There is only one thin finger on the front of the socket cavity that makes positive contact with the connector pin. This finger didn't really provide enough current carrying capability, and it also had a tendency to break off, causing the connection at that position to fail. Gottlieb realized they had a problem and made an engineering change so that each socket position had a pair of ears bending in from both sides of the socket cavity. This worked much better. The ears squeezed the pin to provide better electrical contact, and having the ears on the sides made them a lot less prone to breaking off, although that still happened occasionally.
Based on the vintage games I've worked on, it seems that Gottlieb only used the original version of their patented connector for a few years before switching over to the improved version. I worked on a 1949 Old Faithful, for example, that had the newer style connector.
- TimMe