Abstract: Provided is a tool bracket in which a spindle body is inserted and the spindle body can be smoothly tilted. The tool bracket includes a housing including a cylinder chamber extending along a cylinder axis; a tilting body having a tilt axis configured to tilt about a tilt center, the tilting body to which a spindle body is attachable, the tilting body tiltable with respect to the cylinder axis; a rotation stopper member extending in a radial direction from the tilt axis, the rotation stopper member disposed in the tilting body; and a receiving groove extending along the cylinder axis, the receiving groove arranged in the housing.

Abstract: Provided is a tool bracket capable of tilting a spindle body even when a moment load acting on the spindle body is relatively small. A tool bracket includes: a housing including a cylinder chamber extending along a cylinder axis; a piston urged by compressible fluid toward distal end to reciprocate in the cylinder chamber and having an action portion disposed at distal end; and a tilting body having a tilt axis and disposed in the cylinder chamber in a tiltable manner with respect to the cylinder axis, and includes a centering portion disposed at basal end to abut the action portion, the centering portion presses the piston with the cylinder axis as an action line when the tilt axis is tilted from the cylinder axis.

Abstract: A method and an apparatus for measuring the toner concentration and the amount of electric charge, capable of simultaneously measuring the toner concentration and the amount of electric charge easily and maintaining high precision using a simple device.

Abstract: An optical system of variable magnification comprising one or more multilens units, each of which has a plurality of multilens-arrays positioned at certain spaces in the vertical direction, said multilens units being disposed in such a manner that the optical unit plane, containing optical axes of the lenses in each of the multilens arrays in one multilens unit, intersects other optical unit planes at the center line of said optical system and that each of the optical axes of the lenses in the multilens-array of each of the multilens units gradually deviates one after another from each of those of the corresponding lenses in the next positioned multilens-array within the optical unit plane.Magnifications of the optical system are changed by rotating said optical system around the axis of the intersection line of the optical unit planes to a predetermined position.