Abstract: An ink priming system for a multi-pen recorder of the gravity-fed capillary tube type comprises a gas manifold common to all of the ink bottles individually provided for each channel of the recorder. Individual control valves may be selectively actuated by the operator to prime each pen. When the control valve is closed, the gas pressure is bled off so that the inking system thereafter acts as a normal gravity-fed capillary tube system. A non-clogging inking system is provided by utilizing a short length of flexible thin walled tubing to supply ink to the movable recording pen. The length of this tubing is sufficiently short that evaporation of the ink solvent through the walls of the tube is accompanied by diffusion of the dye back to the ink bottle so that the concentration of dye in the ink at the end of the tube adjacent the recording pen does not exceed saturation value during prolonged periods of non-use of the recorder.

Abstract: A keyboard type switch is disclosed wherein a domed snap disc performs triatic functions of acting as a tactile feedback source for switch operation, of supplying a conductive path for electrical energy when depressed, and of providing a contact surface for manual operation. The disclosed switch is covered by a multilayered nonconductive membrane and spacer to provide maximum safety from electrical shock to the operator.

Abstract: An ink priming system for a multi-pen recorder of the gravity-fed capillary tube type comprises a gas manifold common to all of the ink bottles individually provided for each channel of the recorder. Individual control valves may be selectively actuated by the operator to prime each pen. When the control valve is closed, the gas pressure is bled off so that the inking system thereafter acts as a normal gravity-fed capillary tube system. A non-clogging inking system is provided by utilizing a short length of flexible thin walled tubing to supply ink to the movable recording pen. The length of this tubing is sufficiently short that evaporation of the ink solvent through the walls of the tube is accompanied by diffusion of the dye back to the ink bottle so that the concentration of dye in the ink at the end of the tube adjacent the recording pen does not exceed saturation value during prolonged periods of non-use of the recorder.

Abstract: The present invention is an accessory useful in servicing capillary tube type ink pens associated with strip chart recorders and the like. The device can be used to insert an air bubble into the metallic capillary tube pen during periods of nonuse, flush the pen with solvent when necessary, and prime the pen with ink from an ink supply. The device comprises a container for holding a quantity of ink solvent and having an air pump means such as a bellows communicating with the area above the liquid in the container whereby pressure or vacuum can be applied to the interior of the container. A base member communicates with the liquid in the interior of the container and has an extended tube contained therein terminating at the opposite end in an opening containing a bushing designed to snugly mate with the tip of the recorder pen to provide an airtight/watertight seal.

Abstract: A washable non-splatter ink for use in oscillographic type pen recorders is disclosed. The ink is characterized by being stable at room temperature for extended periods of time, thus not requiring refrigeration for the maintenance of stability. The ink contains a high molecular weight polyacrylamide rather than polyethylene oxide as a pituity agent to stop splatter of the ink at fast writing speeds. The polyacrylamide allows the use of washable acid dyes. The inclusion of an unsaturated alcohol, such as butyne diol acts to retard the oxidation of the pituity, thus stabilizing the pituity against aging degradation.

Abstract: An improved multi-channel galvanometer assembly is disclosed particularly well adapted for use in such instruments as electroencephalographs and the like. The assembly includes a soft steel combination return path structure and frame supporting a plurality of galvanometer movements. The design employs pairs of samarium cobalt magnets held in place adjacent and on opposite sides of the coil of each galvanometer by magnetic attraction to the steel return path structure. The galvanometers themselves are each mounted on an aluminum support plate which also serves as a shield to prevent magnetic coupling between adjacent galvanometer coils when the galvanometers are assembled in the support frame. The galvanometers on their support plates are each individually removable and/or replaceable. The result is a lighter, smaller, multi-channel galvanometer assembly which is readily expandable and easily serviced.