Any owner, part owner or lessee of a hay press, threshing machine, huller or other similar machine who shall press, thresh, or hull any hay, grain, corn, beans, peas or other vegetable products for another, shall, upon the filing of the statement herein provided, have a lien for the value of such services, or in case there is an agreed price, then for such agreed price upon the hay, grain or other products so pressed, threshed or hulled; said lien to commence from the time of filing notice and making demand as hereinafter provided. Such lien shall not attach in any case where the hay, grain or other products which may have been pressed, threshed, hulled or husked, shall have passed into the hands of an innocent purchaser or dealer in the usual course of trade.