Okay this isnt much to go on but it should help a bit.
Your Standard sewing machine was made in Ohio and is the "Slim" variety. The serial number should be in one of two areas, The bobbin plate or on the stitch length regulator. There should not be any letters before the numbers like Singer had in the 1900's.
The patent date just tells us that the earliest the machine could have been made but it does not make it a validation for the year of manufacture.
Post some photos of the feed dogs, that will also help in getting close to the year of manufacture. Alan on the NeedleBar has the dates to serial numbers on the Standard machine company if you go there he can nail it for you no problem. I can only get you in the ball park from the features.
Billy