Abstract: A grinding machine and a method for grinding buttons of a rock drill bit are disclosed. The grinding machine has a frame and a grinding head. The grinding head has a rotatable grinding spindle. The free end of the grinding spindle is intended to drive, and to replaceably carry, a grinding cup. The grinding spindle has a first rotational axis, the grinding spindle being intended to rotate around the same as well as also around a second rotational axis. The first rotational axis of the grinding spindle is arranged to assume at least two separate positions, one of which positions is collinear with the second rotational axis and the second of which positions places the first rotational axis at an angle ? with the second rotational axis.

Abstract: A grinding tool for grinding buttons of a rock drill bit includes a spindle having a longitudinal axis of rotation, and a grinding cup mounted on the spindle by a tongue-and-socket connection. A fastener in the form of a coil spring secures the grinding cup to the spindle. The grinding cup can be inserted into the inside of, or around the exterior of, the coil spring. When the spindle is rotated in a working direction, the spring tightens against the grinding cup. To install or remove the grinding cup, the grinding cup is rotated relative to the spindle in a direction corresponding to the working direction, whereby engagement between the grinding cup and the coil spring becomes loosened.

Abstract: A grinding tool for grinding buttons of a rock drill bit includes a spindle having a longitudinal axis of rotation, and a grinding cup mounted on the spindle by a tongue-and-socket connection. A fastener in the form of a coil spring secures the grinding cup to the spindle. The grinding cup can be inserted into the inside of, or around the exterior of, the coil spring. When the spindle is rotated in a working direction, the spring tightens against the grinding cup. To install or remove the grinding cup, the grinding cup is rotated relative to the spindle in a direction corresponding to the working direction, whereby engagement between the grinding cup and the coil spring becomes loosened.

Abstract: The present invention relates to a method for supplying cooling medium to a grinding cup for grinding buttons of a rock drilling bit. The invention also relates to a grinding cup to carry out the method. A shank of the grinding cup is rotatably mounted in a grinding machine. In prior art grinding cups, the cooling medium is supplied via an axial bore extending through the entire grinding cup. These prior arrangements require the cooling medium to be guided through the grinding machine. The method according to the present invention supplies cooling medium to the portion of the grinding cup that is located axially between a recess of a wear part and the free end of the shank of the grinding cup.