Abstract: A drill bit adapter tool is provided having a lock member, sliding member, and spring that are slidably positioned on the tool body. The lock member engages the driver of a drill and thereby holds the adapter tool to the drill. The lock member is disengaged to permit removal of the adapter tool from the driver by moving the sliding member, lock member, and spring relative to the tool body. The adapter tool facilitates convenient and rapid replacement of drill bits or other working pieces.

Abstract: This device includes a cam which can be adjustably secured intermediate the pedal of a bicycle, which pedal is rotatably mounted on an axle, and the rotary crank of the bicycle to which the pedal axle is secured. The cam carries and defines at least one detent for mechanical engagement. The device also includes a latch mechanism which carries a pawl for releasably mechanically engaging the detentes carried by the cam. A mechanism is provided for normally biasing the pawl into engagement with the detent of the cam. Each of the detentes which is carried by the cam is designed to be located and positioned so that, in conjunction with the pawl, it can position the pedal in one or more desired orientation. One such preferred fixed orientation is with the upper surface of the pedal being horizontal, that is "up," when the crank is in a substantially top dead center position.

Abstract: Method and apparatus for centrally mounting one circular plate relative to another circular plate. The use of such method and apparatus in conjunction with a device for centering and holding a piece of pottery in a central position relative a potter's wheel axis is described.

Abstract: The centering and holding device of the invention is a relatively simple but practical piece of equipment for attachment to a potter's wheelhead for centering and holding the pot such as a vase, bowl, plate or the like on the said wheelhead. The top plate of the device is provided with sliding arms for engaging and holding the pot and the body portion of each arm extends through the top plate to project below for co-action with spiral grooves formed in the surface of the bottom plate. When the plates are rotated relatively to each other the arms move radially and to a like extent.