A machine tool having a drivetrain, which includes a tool shaft rotatably mounted on a drive support by means of a bearing assembly and a tool holder arranged on the tool shaft, wherein the tool shaft is rotationally drivable by a drive motor of the machine tool around a rotational axis, and wherein a balancing device is arranged on the tool shaft, which includes a guide body having at least one orbital path extending around the rotational axis and at least one balancing body movably mounted in the orbital path.

An umbrella base filled with a counterweight comprises an upper cover having a through hole in the center, a base plate, a sleeve, a ring and a counterweight; wherein, the upper cover is placed on top the base plate forming a chamber; the ring stands vertically inside the chamber separating the upper cover and the base plate; the sleeve has a tubular and receives an umbrella column, and is placed vertically on the center of the top surface of the upper cover and aligns with the ring; and a connecting piece is inserted through the base plate, the ring and the upper cover and connects to the sleeve. Or, the bottom of the sleeve passes through the upper cover and screws onto the ring. The umbrella base in the present invention is simple and reasonable in structure, stable and reliable in use, and low in cost, which can meet both usage and environmental protection requirements. It has an appearance not significantly different from that of parasol bases integrally molded by iron plates, and is worth popularizing.

A highly-efficient new-energy vibration controller integrating passive, semi-active and active control, including a multi-cavity beam, a battery assembly, a wound magnetic device, a damping piezoelectric device and an inertia mass assembly. The wound magnetic device includes a connecting rod, an electromagnetic wire wound on a bottom end of the connecting rod and a magnetic box arranged at a bottom of the inertia mass assembly. A top end of the connecting rod is fixedly connected to a bottom of the multi-cavity beam. The bottom end of the connecting rod passes through a center through hole of the inertia mass assembly and arranged in the magnetic box. The magnetic box is provided with a magnetic field. The damping piezoelectric device is sleevedly arranged on an outer wall of the connecting rod. The damping piezoelectric device and the wound magnetic device are both electrically connected to the battery assembly.

A highly-efficient new-energy vibration controller integrating passive, semi-active and active control, including a multi-cavity beam, a battery assembly, a wound magnetic device, a damping piezoelectric device and an inertia mass assembly. The wound magnetic device includes a connecting rod, an electromagnetic wire wound on a bottom end of the connecting rod and a magnetic box arranged at a bottom of the inertia mass assembly. A top end of the connecting rod is fixedly connected to a bottom of the multi-cavity beam. The bottom end of the connecting rod passes through a center through hole of the inertia mass assembly and arranged in the magnetic box. The magnetic box is provided with a magnetic field. The damping piezoelectric device is sleevedly arranged on an outer wall of the connecting rod. The damping piezoelectric device and the wound magnetic device are both electrically connected to the battery assembly.

The present invention provides an internal combustion engine comprising a crankshaft, the crankshaft comprising main bearing journals and cranks for connecting the crankshaft to piston rods of the engine, wherein the crankshaft is provided with counterweights, wherein at least a first counterweight is formed as a separate element and connected to the crankshaft. The present invention is characterized in that at least a second counterweight is formed integrally with the crankshaft.

The present disclosure shows a crankshaft having at least one counterweight that is preferably screwed to the crankshaft via at least two screws, with the counterweight having a contact surface at which it contacts a counter-contact surface of the crankshaft. In this respect, the position of the counterweight at the crankshaft is fixed via at least one positioning element independent of the screw connection.

A mass tuned damper for electric machines, particularly those with an external rotor and an internal stator in cantilever arrangement. The mass tuned damper includes a body with a predetermined mass and a mounting mechanism with a predetermined rigidity configured to couple the body onto a mounting surface of the stator. The mass tuned damper is configured, by varying the mass of body and/or the rigidity of the mounting mechanism, to oscillate at a first frequency equal to, but at least partially out of phase with, a resonance frequency of the stator.

A mass tuned damper for electric machines, particularly those with an external rotor and an internal stator in cantilever arrangement. The mass tuned damper includes a body with a predetermined mass and a mounting mechanism with a predetermined rigidity configured to couple the body onto a mounting surface of the stator. The mass tuned damper is configured, by varying the mass of body and/or the rigidity of the mounting mechanism, to oscillate at a first frequency equal to, but at least partially out of phase with, a resonance frequency of the stator.

A dynamic balancing apparatus includes a dynamic balancing assembly and a plurality of damping particles. The dynamic balancing assembly includes at least two structural members separately arranged on a rotating shaft connected to a rotor, wherein each structural member includes at least one recess portion. The plurality of damping particles are introduced into at least one recess portion of each structural member, such that a centroid of each structural member deviates from the axis. Accordingly, each structural member generates inertial force and moment of inertia as rotation of the rotor to offset another inertial force and moment of inertia generated by centroid deviation of the rotor while rotating to achieve dynamic balance. The plurality of damping particles can move in the recess portion as rotation of the rotor to induce friction and collision so as to achieve the effects of vibration reduction and noise reduction.

A dynamic balancing apparatus includes a dynamic balancing assembly and a plurality of damping particles. The dynamic balancing assembly includes at least two structural members separately arranged on a rotating shaft connected to a rotor, wherein each structural member includes at least one recess portion. The plurality of damping particles are introduced into at least one recess portion of each structural member, such that a centroid of each structural member deviates from the axis. Accordingly, each structural member generates inertial force and moment of inertia as rotation of the rotor to offset another inertial force and moment of inertia generated by centroid deviation of the rotor while rotating to achieve dynamic balance. The plurality of damping particles can move in the recess portion as rotation of the rotor to induce friction and collision so as to achieve the effects of vibration reduction and noise reduction.