A rotation device capable of improving safety includes a plurality of screw holes that each extend along the radial direction of a rotation member and each has an opening on a surface of the rotation member; and a stopper for preventing a screw disposed inside the screw hole from protruding to the outside of the opening, without interfering with insertion of a tool, for turning the screw, into the screw hole.

A rotation device capable of improving safety includes a plurality of screw holes that each extend along the radial direction of a rotation member and each has an opening on a surface of the rotation member; and a stopper for preventing a screw disposed inside the screw hole from protruding to the outside of the opening, without interfering with insertion of a tool, for turning the screw, into the screw hole.

A rotor for use in a centrifuge, and a method for balancing the rotor. The rotor includes a plurality of apertures arranged circumferentially around the rotor's axis of rotation, each configured to selectively receive a weight. A critical speed is determined for the rotor, and an imbalance determined for the rotor at a test speed below the critical speed. A trial weight is installed in a reference aperture, and another imbalance determined at the test speed. The trial weight is repeatedly moved to another aperture angularly displaced from the previous aperture, and the imbalance measured at the test speed until a predetermined number of imbalance measurements have been obtained. A target mass and location for balancing the rotor is determined from the imbalance measurements, and balancing weights installed in apertures based on the target mass and location. The balancing process may be repeated for multiple critical frequencies.

An arrangement for fastening, at multiple fastening points, a power electronic device such as a frequency converter (1) to a base (2) susceptible to vibration, at least a portion of which fastening points are vibration-damped, and which fastening points are on two opposite sides of the frequency converter (1). The invention is realized such that there are at least two fastening points (3, 4; 3, 4, 5) on each of two opposite sides of the frequency converter (1), wherein fastening points (3, 4, 5) on one side are damped while fastening points (3, 4) on the other side are undamped.

An arrangement for fastening, at multiple fastening points, a power electronic device such as a frequency converter (1) to a base (2) susceptible to vibration, at least a portion of which fastening points are vibration-damped, and which fastening points are on two opposite sides of the frequency converter (1). The invention is realized such that there are at least two fastening points (3, 4; 3, 4, 5) on each of two opposite sides of the frequency converter (1), wherein fastening points (3, 4, 5) on one side are damped while fastening points (3, 4) on the other side are undamped.

A fan of the invention includes an impeller having a plurality of blades and rotating around a rotation axis, and at least one balance weight having at least one claw portion and attached to the impeller to correct the center of gravity of the impeller. The impeller has a circumferential convex portion formed along the circumferential direction, and on which the claw portion is hooked to restrict a range of movement of the balance weight in the radial direction of the impeller, and at least one radial concave-convex portion formed along the radial direction, and on which the claw portion is hooked to restrict the range of movement of the balance weight in the circumferential direction of the impeller.

A weight applicator including a weight applicator head and at least one actuator is disclosed. The weight applicator head is adapted to carry a wheel balance weight and has a weight application surface with a weight retaining region and a leading rotation region. The at least one actuator is coupled to the weight applicator head for manipulating the weight applicator head in at least one direction. The at least one direction has a radial component. The leading rotation region is oriented to extend radially further than the weight retaining region.

In a fluid transmission device in which a core is fixed to inner ends of a plurality of blades so as to form, together with a bowl-shaped shell and the blades, an impeller, the core including a plurality of latching holes with which a projecting piece projectingly provided at the inner end of the blade is latched and including a balance weight chip welded to the core, the balance weight chip includes a projecting piece-avoiding hole through which a portion, projecting from the latching hole, of the projecting piece extends, the balance weight chip being welded to the core with a whole of the balance weight chip in intimate contact with the core.

A balancer for a wheel and tire assembly includes one or more tubes 101 containing a movable mass 104. The tube or tubes is/are mounted to a resiliently deformable support 102 with an outer dimension that substantially matches an inner dimension of the tire. the support being arranged to position and support the or each tube within the tire. The/or each tube may be annular. The support may be formed from a plastics mesh 102.

A method for balancing a shaft assembly having a shaft member. The method can include providing a balance weight having a body portion that is formed of a material that permits transmission of ultra-violet (UV) light therethrough, the body portion having a perimeter; applying an UV light-curable adhesive to at least one of the balance weight and the shaft member; positioning the balance weight to the shaft member such that the UV light-curable adhesive is abutted to the balance weight and the shaft member; and transmitting UV light through the balance weight to cure at least a portion of the UV light-curable adhesive that is disposed inwardly of the perimeter of the body portion.