Abstract: An optical liquid sensing system for sensing liquids in contact with an optical sensing component is provided. The sensing system comprises an optical sensor connected to a control module by a fiber optic cable having two fiber optic strands, the first for receiving light emitted by the control module, and the second for receiving light reflected from a distal reflector. The strands terminate in a longitudinally oriented common ferrule within the optical sensor. The optical sensor is generally cylindrical and includes a distal reflector opposite and in a spaced relationship to the ferrule. A group of apertures is defined in the circumferential wall of the housing so as to permit entry of liquid into the housing and to draw liquid proximally located to the sensor into the housing via capillary action.

Abstract: Method and Apparatus for cooling a mold having plural parallel cooling passages therethrough, the mold having flow control means at the inlet and sight glasses at the outlets and being arranged for overfeed so that liquid is always present in all cooling passages to avoid hot spots in the mold.

Abstract: An ink supply connection to both an interchangeable print head and the ink supply container of an ink jet printer system of the asynchronous, volume displacement droplet ejection type, the ink supply including means for automatically closing off the ink supply line to prevent either the loss of ink or the introduction of air into the container, supply and print head when either the print head or the container is removed from the system. The print head includes an ink supply pressure sensor for sensing the changes in pressure in the system and a valve operated by the sensor to supply ink to the system upon reduction of the pressure below a predetermined level.

Abstract: A method of ejecting individual ink droplets on demand from an enclosed ink chamber through a nozzle wherein the pressure of ink within the chamber is controlled to maximize the positive droplet ejecting pressure while controlling the negative pressure cycle to prevent cavitation, and also to return the ink pressure to its steady state static value quickly in preparation for another droplet ejection. The ink pressure is controlled by controlling the volume of the ink chamber and the rate at which it is changed.

Abstract: A recording apparatus and method is disclosed which includes a writing fluid source feeding a drop projection means which ejects a series of droplets of writing fluid from a nozzle in a discontinuous stream with sufficient velocity to traverse a substantially straight trajectory to a recording medium. The volume of each droplet is individually controlled by electrical pulses applied to the projection means from an electronic driver. A plurality of such projection means may be employed and connected to control means whereby to print or form predetermined graphical intelligence patterns on a recording medium.