PURPOSE: To raise the measuring accuracy of an earthquake bearing and the installing work efficiency by measuring exactly a direction for fixing a mule shoe by a compass, determining exactly the setting bearing of a seismometer to be installed to this mule shoe, and installing it.
CONSTITUTION: A compass 4 is set to the upper part of the mule shoe 5, and when it falls in a well pipe 1 with a rope 6, a recessed groove part 7 of the circumferential side face of the mule shoe 5 is engaged to a key 2 provided on a suitable place of the inside surface of the well pipe 1 and stops. In that place, the bearing of the needle of the compass 4 is photographed, and the mule shoe 5 is drawn upward again. After drawin up, both bodies are fixed so that the installation bearing of the seismometer (a) and the mule shoe 5 for installing it faces in the fixed direction in accordance with the bearing of the key 2. Subsequently, when the seismometer (a) falls down by using the mule shoe 5 as a guide, the recessed groove part 7 is engaged with the key 2, to place the mule shoe 5 on a pedestal 3. In this way, the measuring accuracy of an earthquake bearing and the installing work efficiency are raised.
ADACHI NORIHIKO
TAKAHASHI KATSUYA
SUZUKI TAMIO
NISSAKU KK