Abstract: A system for detachably coupling a mixer drive to a mixer in a portable tank, the system comprising a portable tank having a mixer mounted therein and a docking station adapted to receive the tank in an engaged configuration and to have no connection to the tank in a disengaged configuration. The mixer comprises a coupling, such as a magnetic coupling, having a first portion attached to a shaft for driving the mixer, and the docking station comprises a mixer drive having a second portion of the coupling for mating with the first portion. The tank may have one or more components for facilitating and/or maintaining engagement of the tank with the docking station. The docking station may comprise a linkage for converting engagement motion transmitted by the tank in a first direction into engagement motion of the coupling second portion in a second direction.

Abstract: Recording or measuring equipment is provided with a spring clamp or clip for holding a replaceable writing unit by the ink reservoir of the writing unit. The reservoir carries a pen with a fiber or laminar tip and has a vent at or near the end shaped for insertion in the clamp or clip. A plug equipped with a gripping knob is inserted in the vent and the vent is so located that when the plug is so inserted, the ink reservoir cannot be inserted into and held by the clamp or clip, thus assuring that the vent is opened before the pen goes into use.

Abstract: A multiple recorder printing device for recording values of variable amounts on a moving recording tape in the form of consecutive symbols of the same or different colors includes a driven common drive means to both rotate the rotary printing head and move the printing head toward and away from the recording tape. The drive means permits rotation of the rotary printing head to be momentarily arrested during the period that a printing tip on the rotary printing head is in contact with the recording tape to assure clear printing on the recording tape without smudging.

Abstract: The disposable printing head assembly includes a printing head frame structure fitted with a plurality of printing tips or pens. The printing head frame structure includes a plurality of separate store chambers including store material for containing the color printing material. The color store material may be the same or of different colors from one chamber to the other. At least one printing tip is disposed in each color store chamber. The printing tips are formed with different printing symbols such as a point, cross, star or circle.