Abstract: A fluid impact tool of the type known as a percussion or rock drill characterized by a percussion mechanism which provides alternative reverse percussion to assist in drill string removal or recovery.

Abstract: A portion of an air-conditioning unit is divided into two so as to provide first and second air-mixing chambers each following first and second temperature adjustment mechanisms. The temperature of air in the first chamber is controlled independently of the temperature of air in the second chamber, while the first chamber communicates with a first group of air-conditioning zone or zones and the second chamber communicates with a second group of remaining zone or zones. Thus, the temperature of air fed to the first group can be controlled in a manner different from the temperature of air fed to the second group. A plurality of distributing valves are provided at air discharging outlets communicating with the first or second chambers, and the opening degree of each damper may be controlled so that air distribution amount may be controlled.

Abstract: A head parts assembly for use in a two-wheeled vehicle such as a bicycle and a motorbike includes a head pipe, a front fork pipe which extends through the head pipe and a pair of ball bearings to support the head pipe and the front fork pipe to be relatively rotatable from each other. The present head parts assembly also includes a self-adjusting mechanism which allows to maintain the head pipe and the front fork pipe in alignment at all times.

Abstract: An automobile air-conditioning system in which a single ventilation unit for supplying the conditioned air to a compartment is divided into two parts, and the air passing through each part is adapted to be controlled respectively. The compartment is divided into at least three air-conditioning zones of the front right, front left and rear seat zones so that a plurality of air outlets may supply air to the respective air-conditioning zones. The air respectively temperature-controlled is selectively supplied to each of the air outlets.