Stevens guns were made at the plant in Chicopee Falls, Mass. Guns made from 1864 to 1886 will be marked J. STEVENS & CO. From 1886 to 1916 they were marked J. STEVENS A & T CO or J. STEVENS ARMS & TOOL CO. No Stevens firearms were manufactured from 1916 until 1920 when Savage Arms purchased the facilities and name. From 1920 until 1942 (or '48) Savage marked guns J. STEVENS ARMS CO and after that simply STEVENS or STEVENS/SAVAGE. The Stevens name was discontinued in 1991.
The patent date is in fact April 17 94, which is 1894.
What you have sounds like a "Stevens Favorite Rifle Model 1894" if you want to do a search....there is a lot of info and pictures on the web for you. These were sold by the millions, so they are not inheriently rare and valuable, but very collectable.
MODEL 1889 AND 1894 Nos':
No. 17: Basic style with half round/ half octagon barrel. Fitted with standard sights.
No. 18: Half round/ half octogon barrel Fitted with Beach combo frontsight, leaf rear sight and a vernier tang sight.
No. 19: Half round/ half octagon barrel. Fitted with Lyman front sight, leaf rear sight and Lyman tang sight.
No. 20: Round barrel smoothbore. Bead front sight. Receiver top is rounded with a sight groove.
No. 21: BICYCLE RIFLE. Short version o fthe No. 17 with a standard 20" barrel. with carrying case. Other barrel lenghts were special ordered with case. Various sights offered. Produced between 1898 to around 1903.
No. 21: LADIES RIFLE. Half round /half octagon barrel. Checkerd pistol grip stock and forearm. Swiss buttplate. Fitted with beach type front sight, open rear sight and vernier tang sight. Produced between 1910 to 1916.
Value is really hard to say without inspection. Condition is the biggest variable here, folowed by model rarity. Even in poor condition, complete they get $150. Good condition $250 to $350 and really excellent condition a little more but not too much.
Look on the links below to see what people are auctioning them off for and if these are your models......