A gas turbine engine includes a fan and a first drive shaft connected to the fan. A fan drive gear box connects the first drive shaft to a second drive shaft and is configured to allow the first drive shaft to rotate at a different speed than the second drive shaft. The gas turbine engine also includes a sprag clutch disposed circumferentially around the first shaft and connected to the first drive shaft. The sprag clutch is configured to allow rotation of the first drive shaft and the fan in a first direction while prohibiting rotation of the fan and the first drive shaft in a second direction.

The invention relates to a casing, particularly of an axial turbomachine compressor. This casing comprises a support of cylindrical overall shape made of composite material, a metal ring fitted by bonding to the internal surface of the support, and a layer of abradable material fitted by plasma spray onto the internal surface of the metal ring. The metal ring is preferably made of stainless steel and is preferably perforated. The perforation allows better keying of the adhesive and allows the degassing thereof. The external surface of the metal ring is preferably sandblasted prior to bonding. Its internal surface is also preferably sandblasted prior to the plasma spraying of the abradable material.

The invention relates to a casing, particularly of an axial turbomachine compressor. This casing comprises a support of cylindrical overall shape made of composite material, a metal ring fitted by bonding to the internal surface of the support, and a layer of abradable material fitted by plasma spray onto the internal surface of the metal ring. The metal ring is preferably made of stainless steel and is preferably perforated. The perforation allows better keying of the adhesive and allows the degassing thereof. The external surface of the metal ring is preferably sandblasted prior to bonding. Its internal surface is also preferably sandblasted prior to the plasma spraying of the abradable material.

A personal entertainment respiratory apparatus provides air to a user to provide a fully immersive entertainment experience. The personal entertainment system may comprise a flow generator for providing the flow of air. A personal spatial respiratory interface may be coupled to the flow generator. The personal spatial respiratory interface may comprise an outlet for the flow generator. The personal spatial respiratory interface may further be configured to direct the flow of air within an ambient breathing proximity of a user. The personal entertainment respiratory apparatus may further comprise a controller and a sensory particle dispenser. The controller and sensory particle dispenser may be configured to selectively activate release of a sensory particle from the dispenser into the directed flow of air in response to an entertainment triggering signal.

A heat dissipation fan includes a base plate, a frame formed on a side of the base plate, a stator received sin the frame, and a rotor below the stator and connected with the stator. The heat dissipation fan also has an air inlet, a first air outlet and a second air outlet. The air inlet is communicated with the first air outlet and the second air outlet. An angle is defined between each of the first air outlet and the second air outlet.

An axial-flow impeller includes a hub and blades. A tail edge of one blade has recessed portions successively arranged in a direction from a blade root of the blade to an outer edge of the blade. On a reference projection of the impeller on a reference plane perpendicular to a rotation axis of the impeller, a first connection line connects a starting point of a first recessed portion closest to the blade root and an end point of a second recessed portion closest to the outer edge, a second connection line connects a tail edge point of the blade root and the end point of the second recessed portion, one or more of the recessed portions is each partially located at a front-edge side of the second connection line, and remaining one or more of the recessed portions is each completely located between the first and second connection lines.

A motor includes a rotor rotatable about a center axis that extends vertically, a stator opposing the rotor in a radial direction, and a base portion opposing a lower surface of the stator in an axial direction. The base portion includes a lower lid portion extending in a direction orthogonal or substantially orthogonal to the center axis, a protruding portion protruding in the axial direction from an upper surface at a center of the lower lid portion, and a stator holding portion adjacent to the protruding portion in the axial direction and contactable with an inner circumferential surface of the stator. The protruding portion includes a first ventilation portion opening downward at the center of the lower lid portion and a second ventilation portion to cause the protruding portion to communicate with the first ventilation portion.

A blower includes a housing, a fan, a motor, and a speed regulator assembly including a switch for controlling the motor operation, a control member, and an actuating member both enabled to control the switch. The actuating member can move between an off state and an on state. The actuating member can move to a predefined limit position. The rotational speed of the motor corresponding to the predefined limit position is a predefined rotational speed. When the actuating member is in the off state, the motor stops running. When the actuating member is in the on state, the motor rotates. The control member has at least a first control state and a second control state. In the second control state, the motor runs at a maximum rotational speed. In the first control state, the motor runs at an intermediate speed lower than the maximum rotational speed.

The invention relates to an axial ventilator comprising an external or an internal rotor motor that has a rotor (1), at least two blades (4) with end-side connection regions (6) being connected form- and force-fittingly to said rotor (1) and this connection being achieved by bracing said connection regions (6) using a clamping ring (2). The invention is characterised in that said clamping ring (2) comprises recesses (5) that correspond to the number of blades (4) and form, together with one retainer piece (7) in each case, receiving portions (8) for the connection region (6) of the blades (4), said retainer piece (7) being supported against the rotor (1) and the clamping ring (2) being connected, with the inclusion of the connection region (6) of the blades (4), to said rotor (1), preferably to a flange (3) formed on the rotor (1) or to a hub (9), etc.

A counter-rotating axial air moving device includes a front rotor and a rear rotor. The front rotor includes a front hub and a plurality of front blades, and the number of the front blades is equal to or greater than 7 and equal to or less than 11. The rear rotor is disposed on the downstream side of the front rotor. The rear rotor includes a rear hub and a plurality of rear blades, and the number of the rear blades is equal to or greater than 6 and equal to or less than 10. The front rotor and the rear rotor are stacked with each other with a total thickness and a diameter. The ratio of the total thickness to the diameter is equal to or more than 0.91 and equal to or less than 1.5.