Abstract: A marking device wherein liquid is dispensed through the interfacial spaces in a bank of thin blades to an article pressed into engagement with the lower ends of the blades and wherein the flow of liquid to the blades is controlled by maintaining a vacuum in the storage tank which supplies the liquid to the blades characterized in the combination therewith of improved vacuum-producing means by means of which the vacuum of constant predetermined pressure can be maintained with a lesser volume transfer and, hence, with less evaporation of the liquid material, with less work output and, hence, less noise output, and with improved longevity of the apparatus.

Abstract: A marking device comprising a storage tank for holding a quantity of liquid marking material, a horn at the lower end of the tank containing a passage in communication at one end with the interior of the tank within which liquid is maintained by the head of liquid in the tank, a plurality of marking blades at the distal end of the horn with which the opposite end of the passage is in communication for delivering liquid to the blades characterized in that there is a conductor connected to the upper end of the tank for maintaining a vacuum in the tank above the liquid therein and a regulator valve for controlling the vacuum.