Abstract: A number of different embodiments of jumper cables that are constructed to prevent sparking at the batteries where the cables are connected and disconnected. Each embodiment includes a switch means located at the middle of the cables along their length, spaced from the batteries, and in the form of either a hermetically sealed snap switch or a jack and plug arrangement. The switch means may also comprise a timer switch that automatically opens after a predetermined time period of connection. One feature of this invention incorporates jumper cable clamps that operate a cable connected to a power switch so that upon attachment or removal of the cable clamps, the power switch is opened to alleviate spark problems. A further arrangement allows current flow through the battery jumper cables only after all clamp switches are closed and there is a proper polarity matchup between the batteries.

Abstract: An easily adjustable wrench having jaws that move relative to each other. The moving mechanism comprises a pinion gear which is pivotally mounted from one of the jaws and a gear rack on the other jaw with which the pinion gear engages. An actuating button pivots the pinion gear out of engagement with the rack for quick adjustment between the jaws while the pinion gear may be manually rotated for finer adjustments.

Abstract: A system for facilitating the learning of typing by permitting only the proper finger to operate each key. The operator wears a pair of gloves having each finger wired separately to a group of electromechanical devices each for enabling or inhibiting depressing of a key depending upon whether the proper key is being depressed. Each finger has a conductive pad which completes a circuit upon contact with or slight depression of the proper key, or at least proper group of keys, for operating the electromechanical device associated with that key to enable operation of the key. A separate enabling circuit is associated with each finger. If an improper finger is used to depress a key then the circuit is not completed through the finger wire and associated conductive path and the key that is about to be depressed has its associated electromechanical device in a position to inhibit operation of that key.

Abstract: The device is configured so that it is easily held in the user's hand and thereby guided along a strip of recording tape attached to a card, sheet of paper or plastic sheet and having a predetermined message recorded thereon. The device includes a motor for self-propelling the device at the proper tape recording speed. A transducer is mounted for intimate contact with the recording tape as finger and hand pressure are applied. A visual marker or pointer on the device is used for visually guiding the device along the tape. For use with a blind person an embossed ridge may be provided on the card adjacent the tape to permit proper guidance of the device. When using letter-size sheets or cards, it is preferred that a plurality of tape strips be used, each having a message or other indicia associated therewith.

Abstract: A pair of pliers comprising a jaw assembly that is rotatable relative to a handle assembly preferably through a full 360.degree. angle thereby permitting use of the pliers with the jaw assembly in a plane that is independent of the plane of the handle assembly. The jaw assembly comprises a pair of pivotally interconnected jaws each having operating ends and a jaw centering mechanism. The handle assembly comprises a pair of handles fixed to a conic member and a linkage mechanism including a collar. The jaw assembly and the handle assembly are intercoupled by an operating shaft that passes in sequence through the collar and an aperture in the conic member to the jaw assembly whereby upon closing the handles the collar moves the shaft longitudinally thereby passing the operating ends into the conic member causing the jaw assembly to close.