Abstract: A gas turbine engine for an aircraft includes an engine core including a turbine, compressor, and core shaft connecting turbine to compressor; a fan located upstream of the engine core and including a plurality of fan blades each having a leading and trailing edge. The turbine includes a lowest pressure turbine stage having a row of rotor blades, each rotor blades extending radially and having a leading and trailing edge. The engine has a fan tip axis that joins a radially outer tip of the leading edge of a fan blade and the radially outer tip of the trailing edge of a rotor blade of the lowest pressure stage. The fan tip axis lies in a longitudinal plane which contains a centreline of engine. A fan axis angle is defined as the angle between fan tip axis and centreline, and is in a range between 10 and 20 degrees.

Abstract: The present invention relates to a turbo air blower having waterproof and damp-proof functions. The turbo air blower has a waterproof structure so as to be installed outdoor, thereby obviating the need to add a pressure-feeding line and manufacture an air blower room which are required for conventional indoor installation. Further, the turbo air blower has a reliable damp-proof function by installing various dehumidifying parts therein, thereby being capable of preventing a device from being corroded by humidity and dampness as well as providing dehumidified pressure-fed air.

Abstract: A state observation device (30) uses an ADC (37) to digitize a detection signal from a gap sensor (21) at a low-speed sampling period and uses a separation unit (38) to separate the digitized detection signal into vane detection signals considered to be for the detection of a vane of a compressor impeller and non-vane detection signals considered not to be for the detection of a vane. Further, the determination unit (39) extracts a vane peak detection signal considered to be for a vane peak by comparing a vane detection signal with vane detection signals corresponding to other vanes and non-vane detection signals, and a shaft vibration and tip clearance are determined as states of the compressor impeller on the basis of the extracted vane peak detection signal. Thus, the state observation device (30) is capable of observing the state of a rotary machine without carrying out high-speed sampling.

Abstract: A bushing including a body portion including a cylinder portion having a bore there through configured to receive a bolt; a flange portion orthogonal and integral to the cylinder portion, the flange portion configured to abut a load bearing surface of a flange; a lip portion orthogonal to and integral to the flange portion proximate the cylinder portion, wherein the lip portion redistributes a flange load.

Abstract: A vane assembly for a gas turbine includes a first shroud segment, a second shroud segment, a first inner air seal, and a seal assembly. The first shroud segment has a first end face. The second shroud segment is disposed adjacent to the first shroud segment and has a second end face that faces towards and is spaced apart from the first end face by a gap. The first inner air seal extends into the first shroud segment and defines a first trench. The seal assembly at least partially received within the first trench.

Abstract: Provided are non-limiting embodiments of a wear-resistant impeller having a non-conventional blending provided between a surface of a vane (1) and a surface of at least one of a front side shroud (15) and a rear side shroud (16). The impeller may comprise both a rear side blending (3) and a front side blending (2), and the front side blending (2) may comprise a different geometry from the rear side blending (3). The blending preferably comprises a bulbous geometry which is uniquely adapted for optimizing flow patterns adjacent to the vane and between the front and rear side shrouds in a manner which discourages the formation of horseshoe vortices proximate the leading edge (6) of the vane (1) during operation. Through the reduction, mitigation, or elimination of horseshoe vortices, local high velocities and turbulence are generally minimized, and wear experienced by portions of the impeller (e.g., to one or more vanes) from flows of abrasive slurry can be reduced.

Abstract: A spacer of a gas turbine engine is reinforced with a fiber. The fiber can be cured with a substrate to form a fiber reinforced composite material. As a gas turbine engine operates, the rotation creates forces which can deform, expand, contract or translate certain gas turbine engine components, including spacers. These forces can adversely affect gas turbine engine performance and reliability, particularly when they are either unpredictable or difficult to control. Reinforcing a spacer with a fiber may allow a lower system weight, more compact or configurable internal packaging or a high degree of reinforcement.

Abstract: The present disclosure relates to a method of manufacturing composite airfoils bonded to a metallic root. A composite body may be formed with a metallic co-molded member. The co-molded member may be transient liquid phase (TLP) bonded to a metallic root. The metallic root may allow the composite body to be attached to a rotor. The airfoil may also have a metallic edge which is TLP bonded to the composite body via a co-molded edge.

Abstract: A fan may be designed for the strategic diversion of moisture through or around a housing enclosing a controller and/or a motor. The enclosure may include one or more paths for directing moisture away from the controller or the motor. For instance, the housing may include a gap between a support structure and the housing for preventing moisture from entering the housing. The housing may also include a hollow structure for directing fluid through the housing. Additionally, the housing may include one or more channels, raised walls, gutters, and shields for preventing fluid, such as liquid water, from entering an enclosure for the controller or motor.

Abstract: A compressor for a turbine engine includes a shroud having a grooved section including a plurality of groove segments extending radially into a shroud surface. A rotor assembly rotatably supported in the shroud includes a rotor hub and a plurality of rotor blades. Each rotor blade extends radially from the rotor hub and terminates at a blade tip, which is spaced from the shroud surface by a tip gap and defines a non-constant clearance region between a leading edge position and a medial chord position along the blade chord at the minimum tip clearance. The rotor blades generate an aft axial fluid flow through the shroud and the grooved section is formed in the shroud surface upstream of the medial chord position within the non-constant clearance region for resisting a reverse axial fluid flow through the tip gap when the compressor section is operated at near stall conditions.

Abstract: An ceiling fan comprising a motor system. The motor system is mounted around a motor shaft. The motor shaft couples to a downrod for suspending the ceiling fan from a structure. The motor shaft and motor are encased by a motor housing. The motor housing comprises hub arms for mounting a plurality of blade holders. The blade holders coupled to a plurality of blades rotatable about the motor during operation. The downrod comprises a wire disk mounting guy wiring to the downrod. A retention rod is utilized internal of the motor and downrod as a secondary retention method. An electrical connector is internal of the motor shaft and electrically couples to the stator to power the motor.

Abstract: A fan for cooling an electronic device is described, wherein the fan can include an enclosure and a motor secured within the enclosure. The fan can also include an impeller to be turned by the motor, the impeller having a plurality of blades, wherein an angular spacing of the blades results in an audio spread-spectrum within a range of audio frequencies. In some examples, an arrangement of the blades has a center of mass below a threshold, and the angular spacing of the blades and a blade pass frequency (BPF) results in sound that is distributed in the range of audio frequencies.

Abstract: An accumulator device (10) includes at least two accumulator elements (14, 16) that are combined to form a structural unit (12) and that have independently from one another their own accumulator characteristic curves (18, 20), in particular as a result of different preload pressures. The respective accumulator characteristic curves (18, 20) provide a combined total accumulator characteristic curve (22). A fluid can be stored in the structural unit (12) and can be retrieved from it. A hydropneumatic suspension system (24) has such an accumulator device (10).

Abstract: An example valve includes: a piston movable between a neutral position and an actuated position, wherein in the neutral position: a second port of the valve is fluidly coupled to a first port, and a third port is fluidly decoupled from the second port; a solenoid actuator sleeve movable between an unactuated state and an actuated state, wherein in the actuated state, the solenoid actuator sleeve allows pilot fluid to apply a fluid force on a piston in a distal direction; a first feedback spring; and a second feedback spring disposed in series with the first feedback spring, wherein the first feedback spring and the second feedback spring cooperate to apply a biasing force in a proximal direction on the piston against the fluid force, wherein the piston is configured to move to the actuated position based on a relationship between the fluid force and the biasing force.

Abstract: A hydraulic system for a work machine includes a tank to store an operation fluid, a hydraulic device to be operated by the operation fluid, a control valve to control the hydraulic device, a first fluid tube connecting the hydraulic device and the control valve, the first fluid tube being to supply the operation fluid from the control valve to the hydraulic device, a second fluid tube branching from the first fluid tube and connected to the tank, a switch valve provided to the second fluid tube, the switch valve being to control a flow rate of the operation fluid, and an oil cooler provided to the second fluid tube between the switch valve and the tank.

Abstract: A fluid end with an internal bellows can be used in high pressure environments. The bellows is disposed within a plunger bore, and has an interior isolated from a working chamber of the fluid end. An end of a plunger is received in the interior of the bellows. The bellows contains an incompressible fluid at a constant volume. As the plunger extends into the interior of the bellows, the fluid it contains is displaced. Such fluid displacement causes the bellows to extend. As the plunger is retracted, the fluid replaces the volume formerly displaced by the plunger, and causes the bellows to accordion to a retracted position.

Abstract: A stress-engineered frangible structure includes multiple discrete glass members interconnected by inter-structure bonds to form a complex structural shape. Each glass member includes strengthened (i.e., by way of stress-engineering) glass material portions that are configured to transmit propagating fracture forces throughout the glass member. Each inter-structure bond includes a bonding member (e.g., glass-frit or adhesive) connected to weaker (e.g., untreated, unstrengthened, etched, or thinner) glass member region(s) disposed on one or both interconnected glass members that function to reliably transfer propagating fracture forces from one glass member to other glass member. An optional trigger mechanism generates an initial fracture force in a first (most-upstream) glass member, and the resulting propagating fracture forces are transferred by way of inter-structure bonds to all downstream glass members.

Abstract: A rod bracket is provided and includes a bracket base, wherein the bracket base defines a plurality of bracket mounting cavities and includes a base front, a base rear, a base top and a base bottom, a bracket arm having a bracket arm length and a curtain rod cradle securely associated with the bracket base via the bracket arm, wherein the plurality of bracket mounting cavities communicate the base front with the base rear and are configured at an angle of between about 30° and 60° relative to a horizontal plane, and wherein the bracket base defines a first bracket base rear opening, and wherein the ratio between the bracket arm length and the distance between the first bracket base rear opening and the base bottom is about 1:1.

Abstract: A clamping bracket includes base casing, clamping mechanism, controlling mechanism, and anchor mechanism. Clamping mechanism includes first and second clamping members. Controlling mechanism includes a first sliding member being connected to the first clamping member and being slidingly connected to the base casing, and a transmission member being connected to the base casing. Through the transmission member's own movement, transmission member drives the first clamping member to move toward or away from the second clamping member. Anchor mechanism includes a first anchor member that connects to the transmission member and a second anchor member that connects to the base casing. The first anchor member is in an unlock state when separating from the second anchor member and in a lock state when engaging with the second anchor member. Anchor mechanism allows the variable distance between the first clamping member and the second clamping member for holding different mobile devices.

Abstract: According to at least one example, a walking assist system includes a walker having a pair of laterally opposed upright tubular structures connected by at least one laterally-extending tubular portion. The walking assist system also includes a seating device having a first tubular structure formed in an inverted U—pivotably connected by a hinge mechanism to a second tubular structure formed in an inverted U-shape. The seating device also defines a stowed configuration and a deployed configuration. The walking assist system further includes a retention clip defining a first opposing end configured to removably clamp to at least one of an upright tubular structure and the laterally-extending tubular portion of the walker. The retention clip also defines a second opposing end configured to removably clamp to at least one tubular structure of the seating device.

Abstract: In one aspect, a device can include a clip member including a first end and a second end. The first end can be configured to attach to cooking device and the second end can be configured to engage a handle member of the cooking device. The clip member can be configured to be positioned in a handle position where the clip member can be configured to hold the handle member in a substantially fixed position relative to the cooking device when in the handle position.

Abstract: A mount is provided for mounting a plate to a frame assembly. The mount includes a generally cylindrical head extendable through an aperture the plate and having an upper surface, a lower face, an outer peripheral surface, and an alignment structure receivable in a slot of the frame member of the frame assembly. The cylindrical head includes a bolt-receiving bore extending through the cylindrical head along a bore axis at an acute angle to the upper face that is adapted to receive a bolt therethrough. A flange extends radially extending from the outer peripheral surface of the cylindrical head. The flange has a diameter greater than the diameter of at least a portion of the aperture through the plate. Tightening of the bolt captures the plate between the flange and the frame member.

Abstract: A pair of connectable box carcass framework members for the fabrication of non-panel constructed furniture carcasses. They simplify the construction of a furniture carcass with a minimal of tools and skill required to produce a dimensionally square, precisely sized, box that accepts an abundance of aesthetic and functional options. They are based on a pair of mechanical fastener connectable vertical and horizontal members that have connectable zipper channels, linear rabbets for the retention of side panels, screw busses, and open channels with series of spaced orifices therein for the passage of mechanical connectors.

Abstract: The disclosure relates to a first furniture part adapted to be assembled with a second furniture part. The first furniture part comprises recess and the second furniture part comprises a pin. The recess and the pin has a width which varies along the longitudinal direction (L), thereby forming insertion portions of the recess and core portions of the pin, and respective locking portions. The locking portions are provided with grooves and protrusions. The disclosure further relates to a second furniture part comprising a male part of the joint and to a method of forming a furniture part with a female part of a joint.

Abstract: A clip nut 100 has first and second opposed arms 202, 204 extending longitudinally and the second arm 204 includes first and second walls 222, 224 extending transversely of the clip nut, and the first wall 222 includes a first plurality of cavities 234, 236 and the second wall 224 includes a second plurality of cavities 248, 250. A nut 102 includes legs 112, 114 extending into respective cavities. The nut is assembled with the clip nut by putting a leg into a cavity in the first wall and moving the nut toward the second arm to engage a cavity in the second wall.

Abstract: A blind rivet nut includes a rivet sleeve having a set head, a deformation region for forming the closing head, and a threaded section having a female thread. The female thread comprises maximally four complete thread turns, which produces a blind rivet nut with a low mass.

Abstract: A flexible shaft includes first and second shaft portions, first and second angular displacement couplings, and an axial displacement coupling generally extending and centered to a rotational axis. The first shaft portion extends between the first angular displacement coupling and the axial displacement coupling. The second shaft portion extends between the axial displacement coupling and the second angular displacement coupling. The axial displacement coupling includes an outer periphery, first wall attached to and extending radially between the first shaft portion and the periphery, and a second wall attached to and extending radially between the second shaft portion and the periphery. The first and second walls are resiliently flexible to facilitate axial displacement between the first and second shaft portions.

Abstract: A trunnion assembly, comprising at least two pivot-engagement sides located opposite each other, each of the at least two pivot-engagement sides including an attachment hole, each attachment hole including a threaded area and a counterbore, the at least two attachment holes being generally coaxially located relative to each other; and at least one through-hole perpendicular to and midway between the two attachment holes of the pivot-engagement sides; a fastener releasably attached to each of the at least two attachment holes, the fastener including a head and an at least partially-threaded shaft, and a pivot tube disposed around each of the fasteners between the head and the attachment hole, the pivot tube including an inner diameter larger than the diameter of the shaft and an outer diameter smaller than the diameter of a circumscribed circle of the head of the fastener and smaller than the diameter of the counterbore.

Abstract: A slide surface of a thrust bearing includes a planar portion, a taper portion, and a pocket portion. The pocket portion includes a bottom surface, a first side surface, and a second side surface. The first side surface is formed on the side of the taper portion. The second side surface is formed on a side opposed to the first side surface. A depth from the plane of the planar portion to the thinnest portion of the taper portion is between 10 ?m and 80 ?m. A first angle that is an angle between a virtual surface obtained by extending the bottom surface and the second side surface is between 90° and 120°. And a second angle that is an angle between a virtual surface obtained by extending the first side surface and the tapered surface is between 60° and 120°.

Abstract: A pressure indicator assembly disposed in a bearing has a first pressure relief valve and a first piston disposed in a first passage formed in a first component of the bearing and a first proximity switch disposed an initial distance away from the first piston. A first preset pressure value is set on the first pressure relief valve to indicate when pressure within the bearing is greater than or equal to the first preset pressure value.

Abstract: An adjustable spacer with a non-hardened intermediate portion therebetween is mountable between a pair of roller bearings also mounted on a shaft such an axle or spindle or the like. The intermediate portion allows the spacer to collapse in the axial direction to maintain desired axial loads on the bearings.

Abstract: A walking foot for a drilling rig comprising a foot plate attacheable to a drilling rig by an travel plate, capable of functionally bearing a load in excess a quarter of the weight of a drilling rig, comprising a planar roller array wherein a plurality of load rollers with parallel rotational axes are dispersed both laterally and longitudinally within the plane, so as to fractionalize a weight applied perpendicular to the plane, and thereby promote longitudinal motion of the roller array in a direction perpendicular to the plurality of roller rotational axes.

Abstract: A circumferential seal assembly capable of separating a gas into two separate flow paths before communication between a rotatable runner and a pair of seal rings is presented. The seal assembly includes an annular seal housing, a pair of annular seal rings, a rotatable runner, and a plurality of groove structures. The seal housing is interposed between a pair of compartments. The seal rings are separately disposed within the seal housing and separately disposed around the rotatable runner. The groove structures are disposed along an outer annular surface of the rotatable runner. A gas is communicable onto the groove structures. Each groove structure includes at least two hydrodynamic grooves that separate and communicate the gas onto the seal rings. Each groove includes steps whereby the depth of at least one adjoining step decreases in the direction opposite to rotation with or without the depth of another adjoining steps increasing in the direction opposite to rotation.

Abstract: A retainer of an outer ring guide type, includes a retainer guide surface, a relief surface (edge relief groove), and an axial groove. The retainer guide surface is provided on at least one axial end portion of a retainer outer diameter surface and is guided by the outer ring. The relief surface is formed on the retainer outer diameter surface along a circumferential direction, located on an axial center side with respect to the retainer guide surface, and has an outer diameter smaller than that of the retainer guide surface. The axial groove extends from the pockets to an axial end on the retainer outer diameter surface, forms an axial step portion by axially traversing the retainer guide surface, and has a groove bottom on a radial inner side with respect to the relief surface.

Abstract: A bearing housing assembly featuring a bearing housing having a bearing housing wall portion with a bearing assembly chamber for receiving a bearing assembly and a shaft to be rotated, an oil sump for receiving and containing oil for lubricating the bearing assembly when the shaft is rotated, an oil path channel formed as an oil path for receiving dirty oil from the bearing assembly chamber for traveling down the oil path, and a filter assembly wall portion forming a filter assembly cavity coupled fluidically between the oil sump and the oil path channel; and a filter assembly arranged in the filter assembly cavity, to couple to the filter assembly wall portion, receive the dirty oil traveling down the oil path, filter the dirty oil and provide filtered oil to the oil sump, so the filtered oil can be recirculated to lubricate the bearing assembly when the shaft is rotated.

Abstract: A bearing chamber configuration that favorably directs the flow of oil/air mixture inside the bearing chamber of a gas turbine engine is disclosed. The bearing chamber includes an annular baffle surrounding a rotatable shaft. The baffle comprises an annular groove facing radially inwardly and a first radially-inner annular surface extending axially from a first side of the annular groove. The first radially-inner annular surface of the baffle cooperating with the shaft to define a first space inside the bearing chamber and adjacent the seal. The first space is circumferentially uniform.

Abstract: A seal structure includes a rotary shaft that is provided inside a housing, a metal-made surrounding portion of the housing that surrounds the rotary shaft in a radial direction of the rotary shaft, and a resin-made seal member that faces an inner circumferential surface of the surrounding portion and rotates together with the rotary shaft.

Abstract: A constant velocity joint includes balls each rollably supported by an associated one of outer ball grooves and an associated one of inner ball grooves facing each other such that the inclined direction of the associated outer ball groove relative to a central axis of an outer joint member is opposite to the inclined direction of the associated inner ball groove relative to a central axis of an inner joint member. The inner joint member includes escape portions to allow escape of the balls from the inner ball grooves to a first side of the central axis of the inner joint member. Each of the escape portions is provided at least between an end face at the first side of the central axis of the inner joint member and a first rolling guide lateral surface of the associated inner ball groove that forms an acute angle with the end face.

Abstract: A thread-reinforced joint device for a coupling device of a vehicle drive, particularly of a low-platform vehicle, includes a plurality of coupling elements, at least one thread packet coupling two adjacent coupling elements so that a force is transmittable, a support device arranged on at least one of the coupling elements for axially guiding the at least one thread packet and at least one elastic body, into which, the at least one thread packet and the coupling elements are at least partially embedded. The coupling elements are designed and/or can be positioned so that the thread-reinforced joint device is adaptable to different mounting interfaces of a respective coupling device.

Abstract: A structurally and/or functionally improved friction clutch device is disclosed. In particular, a servo spring for a clutch is to be provided which is suitable for series production. In particular, the servo spring is to be realized in the clutch while integrating already existing components. In particular, the servo spring is to keep a maximum disengaging force low. In particular, the servo spring is to operate only under worn conditions; in the new state and during separation it should be possible for it to be force-free. In particular, the total tolerance in the friction clutch device is to remain small, so that the susceptibility of the servo spring force to tolerance deviations is limited.

Abstract: A pressure plate assembly for a motor vehicle with a wear compensation mechanism which comprises a sensor element for sensing wear, wherein the sensor element has an angle lever or is constructed as an angle lever; and a motor vehicle, including such wear compensation mechanism.

Abstract: The present invention relates to a double clutch device (2) with a first clutch (18) for selective torque transmission between a clutch input side (26) and a first clutch output side (28) and a second clutch (20) for selective torque transmission between the clutch input side (26) and a second clutch output side (30), wherein an actuating force (78) counter to the reset force (102) of a first spring device (100) may be applied to the first clutch (18) via a first force transmission element (76) and an actuating force (82) counter to the reset force (116) of a second spring device (114) may be applied to second clutch (20) via a second force transmission element (80). The first spring device (100) extends through at least one recess (104) in the second force transmission element (80).

Abstract: A product comprising: an axle shaft and an input shaft, wherein the axle shaft is coaxial with the input shaft; a clutch operatively connected to the axle shaft and the input shaft constructed and arranged to selectively couple and decouple the input shaft and the axle shaft; an actuator operatively connected to the clutch to drive the clutch; and a synchronizer operatively connected to the clutch to synchronize the coupling of the input shaft and the axle shaft.

Abstract: A clutch assembly includes an output shaft extending along an axis and output teeth. A movable component is disposed adjacent to the output component. The movable component includes drive teeth and an annular engagement weight track including a groove circumscribing the axis. The movable component is movable between an engaged position, wherein the drive teeth are drivingly engaged with the output teeth, and a disengaged position, wherein the drive teeth are not engaged with the output teeth. An input component is disposed adjacent to the movable component. The input component includes engagement weight pockets. Spherical engagement weights are disposed in each engagement weight pocket. The groove has a generally uniform radial cross section across its circumference.

Abstract: A rotary propulsion system for a tiltrotor aircraft operable to transition between rotary and non rotary flight modes. The rotary propulsion system includes an engine that is coupled to a freewheeling unit. A gear system has a torque path coupling assembly between a first gear assembly that is coupled to the freewheeling unit and a second gear assembly that is coupled to a proprotor assembly. The torque path coupling assembly has an engaged position wherein the output of the first gear assembly is coupled to the input of the second gear assembly thereby providing a torque path between the engine and the proprotor assembly. The torque path coupling assembly also has a disengaged position wherein the output of the first gear assembly is independent of the input of the second gear assembly thereby interrupting the torque path between the engine and the proprotor assembly.

Abstract: A clutch controller provides protective disengagement of a clutch between an engine and driven machinery to prevent engine failure due to rapid onset overload. Sensor signals of measured parameters are used by the controller to determine potential engine failure. Multiple, successive sensor signals and elapsed times are assessed during which the current sensor signal value and the scaled rate of change in signal values is compared against a predefined amount. The clutch controller sends a clutch disengagement signal if a calculation result is indicative of imminent failure.

Abstract: A method for controlling a pneumatic actuator (1) of a transmission having at least one sealing element (6, 7) that is arranged between two elements (2, 3) of the actuator (1) that move relative to one another, and within a specifiable operating temperature range in which a leakproofness of the actuator (1) is ensured. The pneumatic actuator is acted upon with compressed air from an air supply system for actuating a transmission component. When a temperature of the actuator (1) is below a glass transition temperature of the at least one sealing element (6, 7), the actuator (1) is acted upon with pre-heated compressed air from the air supply system to warm up the at least one sealing element (6, 7) above the glass transition temperature.

Abstract: A brake caliper housing includes a first end wall, a second end wall, and a transverse wall that extends from the first end wall to the second end wall. The brake caliper housing includes a first bearing protrusion that extends from the first end wall and the transverse wall, and that defines a first lateral bearing surface and a first arcuate bearing surface that extends from the first lateral bearing surface.

Abstract: In a brake device configured to perform braking and releasing of a disc by moving a rod having a lining at a leading end of the rod by a spring device, a cylinder tube of a pressure control unit is arranged adjacent to a pressure storage unit configured to store a compressed fluid. When the disc is to be released, a pressure-receiving piston is moved to a releasing position. When the disc is to be braked, the pressure-receiving piston is returned to braking position.

Abstract: A cable adjuster is provided for a small vehicle including a bicycle. The cable adjuster includes a base portion and a control structure. The control structure includes a first member, a second member and a clutch mechanism. The first member is configured to be rotatably mounted to the base portion about a first axis. The second member is attached to the first member to rotate relative to the first member. The clutch mechanism is configured to transmit rotational force applied to the second member to the first member. The clutch mechanism is also configured to prevent from transmitting rotational force applied on the first member to the second member.