A compressor or pump stage is provided. The compressor or pump stage at least comprising a central shaft (8) and one rotor (3), where the axis of rotation of the rotor (3) is the central shaft (8) and where the rotor comprises a number, n, of rows of impellers (5) arranged at an outer perimeter of the rotor with an axial distance between neighbouring rows of impellers (5), where n={2, 3, 4...}.

A compressor of the regenerative type configured to work at pressures exceeding 50 bars includes a motor, a magnetic drive coupling connected to the motor and adapted to transmit the rotary motion to a drive shaft, which is mechanically connected to the magnetic drive coupling, and two peripheral impellers mounted on the drive shaft.

A compressor of the regenerative type configured to work at pressures exceeding 50 bars includes a motor, a magnetic drive coupling connected to the motor and adapted to transmit the rotary motion to a drive shaft, which is mechanically connected to the magnetic drive coupling, and two peripheral impellers mounted on the drive shaft.

A mechanical assembly for a vehicle (10), in particular a motor vehicle, comprises a rotating element (18), a support Got (20) for the rotating element (18), and a cover (22) attached on the support (20) for the rotating element (18). The cover (22) has at least one edge (50) attached on the support (20) for the rotating element (18) and a bottom (52) extending substantially in a plane. The N bottom (52) is at least partially covered by elastomer material (58).

A mechanical assembly for a vehicle (10), in particular a motor vehicle, comprises a rotating element (18), a support Got (20) for the rotating element (18), and a cover (22) attached on the support (20) for the rotating element (18). The cover (22) has at least one edge (50) attached on the support (20) for the rotating element (18) and a bottom (52) extending substantially in a plane. The N bottom (52) is at least partially covered by elastomer material (58).

A portable electric fan is provided and includes a shell, a fan module, and a plurality of combined seat groups. The shell has a first surface, a second surface opposite to the first surface, and a surrounding side surface that is connected to the first surface and the second surface. The shell has a hollow portion. The fan module is mounted in the hollow portion. The combined seat groups are mounted on the surrounding side surface, and each of the combined seat groups includes two bases and a bracket detachably mounted to the two bases. Each of the two bases has a first through hole and a second through hole, and an extending length direction of the first through hole and an extending direction of the second through hole are staggered relative to the surrounding side surface.

A fan driving circuit includes a primary winding, an activating capacitor, a control circuit, a switch circuit and a secondary winding. The primary winding and the activating capacitor are electrically coupled to an external power source. The control circuit generates a control signal. The switch circuit is electrically coupled to the first winding. The switch circuit is also electrically coupled to the activating capacitor. The switch circuit has at least one control terminal electrically coupled to the control circuit for receiving the control signal. The secondary winding is electrically coupled to the switch circuit. The secondary winding is electrically coupled to the switch circuit. The secondary winding electromagnetically drives a fan according to a flowing direction of its driving current. The switch circuit conducts the secondary winding's driving current's flowing direction based on the control signal's voltage level.

A fan driving circuit includes a primary winding, an activating capacitor, a control circuit, a switch circuit and a secondary winding. The primary winding and the activating capacitor are electrically coupled to an external power source. The control circuit generates a control signal. The switch circuit is electrically coupled to the first winding. The switch circuit is also electrically coupled to the activating capacitor. The switch circuit has at least one control terminal electrically coupled to the control circuit for receiving the control signal. The secondary winding is electrically coupled to the switch circuit. The secondary winding is electrically coupled to the switch circuit. The secondary winding electromagnetically drives a fan according to a flowing direction of its driving current. The switch circuit conducts the secondary winding's driving current's flowing direction based on the control signal's voltage level.

The present disclosure provides an inflation product with a built-in air pump, including an air pump (1), a connection piece (2) and an inflation product (15). The inflation product (15) includes a through hole (151) penetrating from inside to outside, the connection piece (2) is fixed at an opening of the through hole (151), the air pump (1) and the connection piece (2) are detachably connected, and the through hole (151) is provided for the air pump (1) to protrude into with a front end of the air pump (1) exposed outside the through hole (151). The front end of the air pump (1) includes an air inlet (3) in which a normally-closed switch is mounted, and an air inlet sealing cover (5) for driving the normally-closed switch (4) to be pressed down is covered on the air inlet (3).

A motor control system providing at least seventeen speed settings using industry standard control signals and an industry standard five pin speed connector. One speed monitoring pin transmits an output signal for monitoring the speed of the motor, and four speed setting pins receive input signals for setting the speed. One of the speed setting pins receives and decodes two binary states and two frequency states, thereby providing a total of thirty-two speed settings. A non-regulated isolated winding is added to an internal transformer to provide an internal isolated flyback power supply for the motor, thereby liberating a pin on the industry standard five pin speed connector to provide the fourth speed setting input pin. Transmission circuitry is associated with the speed monitoring pin, and the non-regulated isolated winding is used to provide a direct current bias to the transmission circuitry.