A machining center for machining a center groove on a pulley and a flange formed at opposite ends of a crankshaft of a vehicle includes a measurement unit configured to measure a moment of the crankshaft when the crankshaft is loaded and actuated, a control unit configured to calculate an imbalance amount of the crankshaft and to derive center drill coordinates for removing the imbalance amount, a compensation unit mounted in a base frame and configured to compensate a position of the crankshaft by rotating first and second rotating elements based on the center drill coordinates inputted from the control unit when the crankshaft is transported and clamped by a clamping system, and a machining unit configured to machine the center groove in the pulley and the flange of the crankshaft.

A test apparatus determines the state of torsional balance of an elongate device about its longitudinal axis. It has a base plate, supporting two sets of longitudinally spaced-apart low-friction roller bearings. The second bearings are mounted on the base at a higher location than the first bearings. A support for the second bearings has a side opening to allow lateral movement of the device under test into engagement with the underside of the second bearings which resting on the upper side of the first bearings. The device under test may be a rifle or a golf putter, the barrel or shaft respectively of which is supported on the roller bearings of the first set and in contact with the underside of the second bearings. The device will rotate about the longitudinal axis if not balanced about the axis. It is very easy and convenient for the user to place the tube in the guide to check for balance whenever checking balance of the item. The side opening allows use with a variety of devices having irregular shapes along its length.

The invention relates to a method for reducing an imbalance of a projectile shell. The projectile shell has a body (1) which has a recess (4). By this recess (4), the body is provided with an inner wall (2) and an outer wall (3). In addition, a mouth hole (6) is provided, which is connected to the recess (4). A central axis (5) is now calculated from the outer geometrical shape of the projectile shell and a measurement is then performed to ascertain an imbalance of the projectile shell. On the basis of the measured imbalance, modified axis (8) is then calculated in relation to the central axis (5), and the body (1) is rotated about the modified axis (8) on the basis of the calculated modified axis (8). As the body (1) is rotated in this way, the projectile shell is machined to eliminate the imbalance as far as possible.

A balance adjustment method for a rotor includes an imbalance acquisition step of acquiring imbalance position and amount of the rotor after a first balance correction step of correcting balance of the rotor by cutting a compressor wheel side, an excision target section determination step of determining, based on the imbalance position and amount of the rotor, an excision target range including an imbalance correction position of the turbine wheel and a removal amount in the excision target range, and a second balance correction step of correcting the balance of the rotor by repeatedly irradiating the excision target range determined in the excision target section determination step with laser light from a laser marker device to remove by the removal amount from the turbine wheel.

A rotor of a fluid machine includes a wheel with a plurality of blades. Furthermore, the rotor includes an inter-blade area defined circumferentially between a first blade and a second blade of the plurality of blades with respect to the axis of rotation. Moreover, the rotor includes a balancing mark on the wheel and within the inter-blade area. The balancing mark is elongate and has a first end and a second end. The first end and the second end are stepped axially into the inter-blade area. The balancing mark extends arcuately between the first end and the second end. The balancing mark has a depth that varies as the balancing mark extends arcuately between the first end and the second end. The balancing mark has a width that varies as the balancing mark extends arcuately between the first end and the second end.

A rotor of a fluid machine includes a wheel with a plurality of blades. Furthermore, the rotor includes an inter-blade area defined circumferentially between a first blade and a second blade of the plurality of blades with respect to the axis of rotation. Moreover, the rotor includes a balancing mark on the wheel and within the inter-blade area. The balancing mark is elongate and has a first end and a second end. The first end and the second end are stepped axially into the inter-blade area. The balancing mark extends arcuately between the first end and the second end. The balancing mark has a depth that varies as the balancing mark extends arcuately between the first end and the second end. The balancing mark has a width that varies as the balancing mark extends arcuately between the first end and the second end.

A mixed-flow turbine wheel includes: a plurality of rotor blades disposed on a circumferential surface of the hub at intervals in a circumferential direction and configured such that each of the plurality of rotor blades has a leading edge which includes, in a meridional view, an oblique edge portion where a distance between the leading edge and an axis of the rotational shaft decreases from a tip side toward a hub side, and a sensor detection surface having a flat shape and being applied with a marking which is detectable by an optical sensor device. The sensor detection surface is formed on at least one of the circumferential surface of the hub or an edge portion of a reference rotor blade being one of the plurality of rotor blades, such that, in the meridional view, a trailing-edge side angle of two angles formed between the axis of the rotational shaft and a normal of the sensor detection surface is smaller than a trailing-edge side angle of two angles formed between the axis of the rotational shaft and a normal of the oblique edge portion.

A manufacturing apparatus for manufacturing a blower blade including a plurality of blade portions having the same shape and arranged around a rotation axis line includes a machining device for machining the blower blade and a control device for controlling the machining device. The control device includes a command creation unit for creating an operation command to the machining device according to a machining program and a machining parameter, a balance measurement unit for measuring balance of the blower blade, and a machining amount adjustment unit configured to individually adjust a machining amount of each of the blade portions without changing the machining program, based on data of the balance of the blower blade measured by the balance measurement unit so as to reduce unbalance of the blower blade. A manufacturing method using the above-described manufacturing apparatus is also provided.

A manufacturing apparatus for manufacturing a blower blade including a plurality of blade portions having the same shape and arranged around a rotation axis line includes a machining device for machining the blower blade and a control device for controlling the machining device. The control device includes a command creation unit for creating an operation command to the machining device according to a machining program and a machining parameter, a balance measurement unit for measuring balance of the blower blade, and a machining amount adjustment unit configured to individually adjust a machining amount of each of the blade portions without changing the machining program, based on data of the balance of the blower blade measured by the balance measurement unit so as to reduce unbalance of the blower blade. A manufacturing method using the above-described manufacturing apparatus is also provided.

A procedure defining a balancing strategy includes: providing a computer model which predicts the vibration amplitude at a given axial position along the spool when the spool is rotated at a given rotational speed; using the model to predict respective vibration amplitudes at the given axial position for different axial positions of a unit unbalance applied to the spool; plotting the predicted vibration amplitudes as data points on a graph of vibration amplitude against axial position of the applied unit unbalance; using the graph to identify axial positions which are more or less likely to contribute to flexing of the spool at the given rotational speed when mass is added or removed from the first rotor module to reduce imbalances at the axial positions; and defining a balancing strategy based on the identification.