US Patent 9341173 Lance pump with a ram

An improved lance pump is disclosed for pumping a pumpable product, particularly lubricant including grease, from a lubricant supply. The pump comprises a head for placement above the supply, a tubular lance structure affixed to the head and extending down into the supply, and a pump tube inside the lance structure that is reciprocated up and down for pumping lubricant from the supply on both upstrokes and downstrokes of the tube. A ram at a lower end of the lance structure is positioned for forcing lubricant up into the tube and past an inlet check valve on a downstroke of the tube.