Provided is a small-sized propeller windmill which can efficiently generate power even when a wing speed is low, has no possibility that the windmill is broken even when a strong wind blows, can stably ensure a weathercock direction of a base blade, and can suppress an environmental burden, in such a propeller windmill, the blade having a corrugated wing shape is supported in a cantilever manner by way of an elastic body, and the blade and the elastic body are made of paper or plastic. Further, to stably ensure the weathercock. direction of the base blade, a weathercock stabilizing mechanism is arranged behind the base blade.

The present invention relates to a wind turbine nacelle having a first face with a longitudinal extension in a wind direction, comprising a cooling device having a cooling area and extending from the first face of the nacelle, and a cover having at least one inner face, the cooling device being enclosed by the first face of the nacelle and the inner face of the cover. A first distance between at least one of the faces and the cooling area is at least 30 mm.

The present invention relates to a wind turbine nacelle having a top face with a longitudinal extension in a wind direction, comprising a cooling device extending from the top face of the nacelle and a cover having at least one inner face. The cooling device is enclosed by the top face of the nacelle and the inner face of the cover.

The invention relates to a wind turbine blade with at least one control surface and an actuator inside the main body of the wind turbine blade for moving the control surface, wherein the actuator comprises a fluidic muscle, a controller and a pump, and wherein the fluidic muscle is adapted to change in length and width when the pressure of the fluid within the fluidic muscle is varied.

A winglet for a rotor blade is disclosed. The winglet may generally include a winglet body extending between a first end and a second end. The winglet body may define a sweep and may have a curvature defined by a curve fit including a first radius of curvature and a second radius of curvature. The sweep between the first end and the second end may range from about 580 millimeters to about 970 millimeters. Additionally, the first radius of curvature may range from about 1500 millimeters to about 2500 millimeters and the second radius of curvature may range from about 1200 millimeters to about 2000 millimeters.

A wind turbine for generating electrical energy may include a wind turbine blade including a plurality of vortex generators integrally formed in the outer surface of the blade. The vortex generator includes a first component that defines a portion of the outer surface of the blade and a second component defining the shape of the vortex generator and at least partially surrounded by the first component. A method of manufacturing the wind turbine blade includes disposing a first plurality of layers of structural material over a mold main body and a removable insert member with a shaped cavity. A shaped plug is then pressed into the shaped cavity, and a second plurality of layers of structural material is disposed over the plug and the mold main body to complete manufacture of a wind turbine blade with a vortex generator.

A wind turbine blade with a lightning protection for a blade with a shell body has at least one lightning receptor arranged freely accessible in or on a surface of the shell body surface, and a lightning down conductor electrically connected to the lightning receptor and comprising an inner conductor made of electrically conductive material imbedded in a bedding insulation made of an electrically non-conductive material. The lightning down conductor further includes a first conductive layer having a resistance in the range of 10 to 10,000 Mega Ohm per meter (MΩ/m). The first conductive layer is located in a transverse distance from the inner conductor and being electrically isolated from the inner conductor.

A balun including a first conductor winding, a first inductor, a second inductor, a third inductor, and a fourth inductor. The first conductor winding has a figure eight shape including a first loop and a second loop. The first inductor and the second inductor substantially surround the first loop. The third inductor and the fourth inductor substantially surround the second loop.

A wind power generator generates power through a rotation of a rotor and is interconnected, and operated with its power generation output previously limited in order to be able to further supply the power to a power system in response to a decrease in system frequency. Thus, a concentrated control system derives a required restricted amount corresponding to a power generation output required to respond to the decrease in system frequency, derives a value by subtracting an amount corresponding to a latent power generation output with which the power generation output can be increased, from the required restricted amount, and sets a restricted amount of the power generation output in each wind power generator to perform the operation with the power generation output previously limited to respond to the decrease in system frequency, based on the above value.

A wind energy plant comprising a rotor having blades and a generator driven by said rotor for generating electric energy. The pitch of the blades can be adjusted and a pitch system for adjusting the pitch angle of the blades is provided, which is supplied by a hub power source. An additional electric load is provided on the hub. A pitch power control device is provided which dynamically distributes the power of the hub power source between the pitch system and the additional electric load and further acts on the pitch system such that its power consumption during high-load operation is reduced. Thus, the power consumption of the pitch system during high-load operation can be reduced and additional power provided for operating the additional load. Even large additional loads, such as a blade heater, can be operated in this way, without having to boost the hub power source.

The control system of this floating wind turbine generator is a control system of a floating wind turbine generator in which the control system controls a pitch angle control section by a pitch angle instruction value calculated on the basis of signals detected by a second sensor detecting a relative angle between a nacelle and a tower and a third sensor detecting a yaw angle from a reference position of the tower so that a signal detected by a first sensor detecting wind direction deviation relative to a vertical direction of a rotation plane of wind turbine blades indicates an angle within a predetermined range from the vertical direction of the rotation plane of the wind turbine blades, and controls a yaw driving device by a yaw driving instruction value calculated on the basis of the signals detected by the second sensor and the third sensor.

A wind turbine is provided. The wind turbine includes a generator, an output thereof being connectable to a power grid via a power transmission path, the power transmission path comprising a generator side converter coupled to the output of the generator, a grid side converter coupled to the power grid, and a DC link coupled between the generator side converter and the grid side converter. For diverting the generator power, a load dump arrangement is provided which includes at least one resistor, a plurality of switches, and a plurality of electrical connections which electrically connect the at least one resistor to the output of the generator and across the DC link via the plurality of switches. One common and configurable load dump is used for both converter system failures and grid failures. As compared to two separate load dumps for converter failures and grid failures, the single load dump will require a smaller space for a wind turbine. Thus, the weight and size of the power converter system may be reduced.

According to an embodiment, a method of operating a wind turbine comprising a DC-to-AC voltage converter is provided, the wind turbine being connectable to a grid via the DC-to-AC voltage converter, the method comprising: determining a line voltage of a power line connecting the DC-to-AC voltage converter to the grid; if the determined line voltage exceeds a predefined voltage threshold value, injecting reactive current into the power line, wherein the amount of reactive current injected is chosen such that an output voltage of the DC-to-AC voltage converter is kept within a predetermined voltage range.

A method of operating a converter of a wind turbine for providing electric energy to a utility grid includes determining a grid voltage. If the grid voltage is between a nominal voltage and a first voltage threshold, i.e. higher than the nominal voltage, a normal procedure for lowering the grid voltage is performed. If the grid voltage is above the first voltage threshold, another procedure for keeping the wind turbine connected is performed, wherein the other procedure is different from the normal procedure. Further a corresponding arrangement is described.

Wind turbine systems and methods are provided. An exemplary system includes a wind driven doubly fed induction generator having a rotor and a stator, the stator providing AC power to a stator bus. The system further includes a power converter coupled to the rotor of the doubly fed induction generator, the power converter providing an output to a line bus, and a transformer coupled to the stator bus. The system further includes a solid-state switch coupled between the stator bus and the transformer.

Systems and methods for reducing current imbalance between parallel bridge circuits used in a power converter of a doubly fed induction generator (DFIG) system are provided. A control system can monitor the bridge current of each of the bridge circuits coupled in parallel and generate a feedback signal indicative of the difference in bridge current between the parallel bridge circuits. Command signals for controlling the bridge circuits can then be developed based on the feedback signal to reduce current imbalance between the bridge circuits. For instance, the pulse width modulation of switching devices (e.g. IGBTs) used in the bridge circuits can be modified to reduce current imbalance between the parallel bridge circuits.

A method is employed for operating a wind turbine. Electrical energy is produced by means of a generator and is fed into an electrical power network. The electrical energy is fed to the secondary side of a transformer at a low voltage and is output on the primary side of the transformer at a higher voltage. The potential on the primary side of the transformer is undefined. In the method, a measured value of the voltage between the primary side of the transformer and the earth potential is first recorded. The measured value is compared with a predefined limit value. The electrical energy produced by the generator is changed if the measured value exceeds the limit value. A wind turbine is designed to carry out the method. Faults in the medium voltage network can be reacted to without an additional star point on the primary side of the transformer being required.

A retractable cord winder device, which has a front cover with center shaft, a spiral spring, a spool with a spool divider with flanged hook dividing the spool chamber into equal halves for efficient and minimal noise cable coiling, oval sliding positioning sliding disc, and a rear cover with concave recess to hold the oval positioning sliding disc with positioning stopper. The front cover is mounted with the rear cover through the center shaft via a center hole of the rear cover where there are symmetrical openings on both ends for cords folded in half to be attached to the flanged hook and retracted upon pulling down.

A method and device for winding a rotor or a stator (2), of a rotary electrical machine, having a series of teeth (21) which are delimited by notches (22). In each notch there are inserted M continuous electric wires (3) constituting a turn; M being equal to 1 or more, characterised in that n×M wires (3) are wound simultaneously in a number n of notches (22), n corresponding to the number of phases and being ≧2. The assembly of the M wires (3) constituting a phase, being inserted in a single notch (22). The device for winding has at least two carriages (4, 5), with a series of teeth, delimited by n notches (40, 50). And, likewise corresponding to the winding, each set of M continuous electric wires (3) constituting a turn, is characterised in that M×n wires (3) are inserted simultaneously in the extension of the n notches (22) of the rotary electrical machine in the n notches (40, 50) in the respective carriages (4, 5). All of the M×n wires (3) are bent together at least twice by bending the carriages (4, 5) relative to one another, and all of the M×n wires (3) thus bent are folded back in the following successive n1 notches (22) of the rotary electrical machine.

A system and process is described for producing spirally wound products. According to the process of the present disclosure, two or more webs are conveyed together in a superimposed relationship. The webs are then separated such that one web goes to a first winding module while a second web goes to a second winding module, etc. In this manner, at least two spirally wound products can be produced simultaneously. The process and system of the present disclosure are particularly well suited for processing tissue webs, such as paper towels and bath tissue. The process of the present disclosure can effectively at least double throughput on existing winding systems.

In a webbing winding device, even when a piston moves toward the other side in a movement direction due to a reaction when the piston moves to a maximum movement position, an engagement surface of a hook portion comes into contact with a subject engagement surface of a subject engagement portion, so that the movement of the piston toward the other side in the movement direction is restricted. Accordingly, the piston is prevented from returning to a standby position, and a pawl is prevented from returning to a lock position. For this reason, a state where a rotation of a locking ring in the pull-out direction is maintained. Accordingly, after the piston moves from the standby position to the maximum movement position, the piston is prevented from returning to the standby position, and the force limiter load is prevented from being changed.

A filament winding apparatus prevents a fiber bundle supplied to a liner from interfering with other fiber bundles and fiber supplying guides. First and second guide units include a plurality of fiber supplying guides arranged radially and extending and contracting in a direction approximately perpendicular to a liner central axis. When a fiber bundle supplied from a first supplying guide of the first guide unit crosses between a second supplying guide of the second guide unit and the liner, the distance from the second supplying guide to the liner central axis is made larger than the distance from the first supplying guide to the liner central axis, and in the reverse case, the distance from the first supplying guide to the liner central axis is made larger than the distance from the second supplying guide to the liner central axis.

A web rewinding apparatus having a mandrel cupping assembly for releaseably engaging unsupported ends of a plurality of mandrels is disclosed. Each of the plurality of mandrels extends generally parallel to the web winding turret assembly axis. Each of the mandrels is driven in a closed mandrel path about the web winding turret assembly axis. The mandrel cupping assembly comprises a cupping arm turret having a cupping arm turret central axis, a mandrel cup cooperatively associated with each mandrel of the plurality of mandrels, at least three motion limiting devices disposed upon the cupping arms, and a first actuator.

The wire winding apparatus includes: a wire feeding member provided to a supporting member so as to be operable, for feeding a wire; a lock mechanism capable of inhibiting an operation of the wire feeding member; a winding mechanism for rotating a core about an axis thereof to wind the wire fed from the wire feeding member around the outer circumference of the core; a feed mechanism for moving the supporting member in an axial direction of the core in synchronization with the winding performed by the winding mechanism; a proximity sensor for detecting a movement amount of the wire feeding member with respect to the supporting member; and a control section for controlling an operation of the feed mechanism to adjust a movement amount of the supporting member moved by the feed mechanism based on a detection output from the proximity sensor.

A filament winding apparatus prevents a fiber bundle supplied to a liner from interfering with other fiber bundles and fiber supplying guides. First and second guide units include a plurality of fiber supplying guides arranged radially and extending and contracting in a direction approximately perpendicular to a liner central axis. When a fiber bundle supplied from a first supplying guide of the first guide unit crosses between a second supplying guide of the second guide unit and the liner, the distance from the second supplying guide to the liner central axis is made larger than the distance from the first supplying guide to the liner central axis, and in the reverse case, the distance from the first supplying guide to the liner central axis is made larger than the distance from the second supplying guide to the liner central axis.

Laser light is emitted to a sheet member wound on a forming drum in a range which includes the entire width of the sheet member and distance data on a distance to a reflecting surface is obtained, using a two-dimensional laser sensor which has a detection range along a drum circumferential direction, while moving either the two-dimensional laser sensor or the forming drum in a drum width direction. Further, the positions of width-directional opposite end sections of the sheet member are calculated on the basis of the obtained distance data.

To provide a wire unwinding auxiliary device capable of, compared to a conventional device, effectively preventing an unwound wire material from getting twisted, entangled or flawed. A wire unwinding auxiliary device used for guiding an unwound wire material when unwinding the wire material which is wound in a coiled shape. The device comprises a plurality of rotation members 1a-1e on which the unwound wire material is set to run therethrough, and a non-rotation member 2 provided adjacent to at least a rotation member 1a through which the wire material passes first in the plurality of rotation members 1a-1e, thereby a running path of the wire material is stabilized between the non-rotation member 2 and the rotation member 1a.

A geared motor actuator having a simplified mechanical structure for driving a closing part, such as a vehicle window, moved as far as at least one end position by an electric motor (MO) via a gear (G), preferably a worm gear. Shortly before the end position is reached, switch-off of the electric motor (MO) is performed in accordance with a control device (ST). The gear (G) is drive-connected to an output driver of the closing part without any damping means. The worm wheel (4) of the worm gear, being a solid, integral component that is preferably injection-molded from plastic, is preferably designed to include the output driver as part of the integral component, and provided with a drive pinion (4.1).

Disclosed herein is a drying apparatus for a vehicle using vehicle induced wind. The drying apparatus is capable of drying a wet object using vehicle induced wind generated by the driving of the vehicle. The apparatus includes a storage cover that is rotatably coupled to a rear bumper cover via a hinge module, to form a storage space between the storage cover and the rear bumper cover. In addition the apparatus includes an inlet cover that is coupled to the rear bumper cover to form an inlet passage through which the vehicle induced wind flows into the storage space when the vehicle is being driven. A plurality of outlet holes are formed in the rear bumper cover, and are configured to operate as a passage to allow air to be discharged from the storage space to an exterior of the vehicle.

A “windowless” H-bridge buck-boost switching converter includes a regulation circuit with an error amplifier which produces a ‘comp’ signal, a comparison circuit which compares ‘comp’ with a ‘ramp’ signal, and logic circuitry which receives the comparison circuit output and a mode control signal indicating whether the converter is to operate in buck mode or boost mode and operates the primary or secondary switching elements to produce the desired output voltage in buck or boost mode, respectively. A ‘ramp’ signal generation circuit operates to shift the ‘ramp’ signal up by a voltage Vslp(p−p)+Vhys when transitioning from buck to boost mode, and to shift ‘ramp’ back down by Vslp(p−p)+Vhys when transitioning from boost to buck mode, thereby enabling the converter to operate in buck mode or boost mode only, with no need for an intermediate buck-boost region.

According to one embodiment, a windshield attachment device for coupling a windshield to a body includes a fastener portion, a bolt, and an elastomeric load isolator. The fastener portion has an opening therethrough. The bolt is configured to extend through the opening of the fastener portion and couple the fastener portion to the body. The elastomeric load isolator surrounds at least a portion of the fastener portion and separating the fastener portion from the windshield.

A casing window assembly for completion of a lateral wellbore. The casing window assembly includes a tubular casing sleeve with a casing window and an inner sleeve releasably secured within the casing sleeve at a pre-released position adjacent the casing window.

A stranding of long winding material using a substantially cylindrical rotary body. The rotary body includes a first passage for guiding a first winding material through the cylindrical rotary body and a second passage for guiding a second winding material through the cylindrical rotary body. The first passage connects a first offset inlet on a first end side of the rotary body to a first offset outlet on a second end side of the rotary body, which opposes the first end side. The second passage connects a second input, arranged on a surface of the rotary body extending between the two end sides, to a second offset output on the second or first end side of the rotary body.

The present invention relates to a steel net reinforcement structure which is used for a conveyer belt or a shutter screen. The steel net reinforcement structure comprises: a steel net including hooks projecting from both sides thereof; a reinforcement including a slit cut open along a diagonal direction on both sides thereof; and a steel core which can lock the hooks which are inserted on both inner sides of the reinforcement. The steel net reinforcement structure can be wound conveniently and flexibly while reinforcing strength of the steel net.

In a bead wire winding and forming device, a guide mechanism guiding a bead wire to a former is supported to be movable in a tangential direction of the former and includes a movable body capable of clamping and unclamping the bead wire, a guide body supported on the movable body to be swingable in a plane parallel to a rotational axis of the former and having a guide portion for guiding the bead wire in the tangential direction of the former, and a restriction member for allowing the swing motion of the guide body when the movable body is at a retracted position but for restricting the swing motion of the guide body when the movable body is at an advanced position.

The winding mandrel includes a pair of generally rounded-cube shaped or orthogonally flat-sided spherical main bodies connected together and having a plurality of cylindrical posts for forming vasoocclusive coils. The main bodies are connected together by a transition post, and the posts of the two main bodies are typically offset. A front end post and back end post are disposed on the front and rear ends of the mandrel. A short winding post member may be added between the connections of the two main bodies to provide additional winding posts.

A method and an apparatus for handling and/or servicing components of a wind turbine, such as installing and/or dismantling components into or from a wind turbine nacelle or such as servicing exterior components such as blades, hub, tower and nacelle of the wind turbine are disclosed. The gripping apparatus comprising at least one arm for gripping around the wind turbine tower, the at least one arm capable of forming a gap between gripping elements of the gripping apparatus. The at least one arm extends around the entire outer circumference, seen perpendicular to a horizontal plane, of the wind turbine tower.

A method for mounting a wind turbine blade to a wind turbine hub by use of a crane boom is provided. An orientation of the blade is kept substantially horizontal when the blade is lifted off the ground and mounted to the rotor hub. Control wires, which connect the blade via the crane boom to a winch arrangement, are used for keeping the blade orientation substantially horizontal in addition to at least one bearing wire for bearing the blade weight.

The invention relates to a device for mounting and/or dismantling a component (10), in particular a rotor blade of a wind turbine (20) comprising a tower head (21). Said device comprises at least one guide element (30) that stretches between the tower head (21) and the ground (40) and has at least one supporting device (60) that is essentially fixed in the air, supporting at least a partial load of the weight of the component (10) during the transport of the latter (10) between the ground (40) and the wind turbine (20). At least one guy (70) leads from the supporting device (60) to the component (10), whereby the length of said guy between the supporting device (60) and the component (10) can be modified.

An insulated window buck with integrated fastening and anchor elements for a self aligning cut or molded insulated concrete form (ICF) window buck. The insulated window buck with integrated fastening and anchor generally includes an insulated ICF window and door buck made with multiple components with a configuration that allows for the use of various type of materials' on the face and edges of the buck, and have the ability to friction fit to the inside of an ICF wall so as no external bracing or strapping is needed to keep the buck aligned with the ICF wall during concrete placement. Having a firm insulation material component on the internal portion of the buck is an integral part of the invention in that through the use of recesses in the insulation material the fluid concrete can flow into these recesses and make a permanent bond to the buck. Also having the ability to use single or multiple insulation pieces to make up the insulating and friction fit element of the buck is an integral part of the invention.

An electro-hydrodynamic wind energy conversion system is presented. The system includes a wind passage allowing wind flow. Further, the system includes a reservoir having an opening in communication with the wind passage and configured to hold a liquid. The system also includes an agitator coupled to the reservoir and configured to convert the liquid into droplets. Additionally, the system includes a charging system disposed substantially opposite the reservoir opening and configured to deposit an electrostatic charge on the droplets and draw the droplets into the wind passage. Moreover, the system includes a charge collector disposed at a distal end of the wind passage and configured to collect the electrostatic charge from the droplets.

Provided is a window glass sheet fitted with a seal member and incorporated with a device such as a deicer which facilitates the device and the seal member to be installed in a proper manner. The automotive window glass sheet comprises a laminated glass sheet including a first glass sheet and a second glass sheet placed on an outboard side of the first glass sheet, and a seal member fitted on a peripheral part of the laminated glass sheet. The automotive window glass sheet further comprises a cutout formed on an edge of the first glass sheet, an electrode provided on a part of the inboard side of the second glass sheet corresponding to the cutout, a lead wire connected to the electrode and a spacer extending along an edge of the second glass sheet on the inboard side of the second glass sheet in a part thereof corresponding to the cutout and defining a flat and smooth inboard surface, wherein the inboard surface of the spacer is flush with a plane extrapolated from an inboard side of the first glass sheet, and the seal member is attached to a peripheral part of the inboard side of the first glass sheet and is attached to the inboard surface of the spacer in the cutout.

A windowed muzzle has left and right side sections, a lower section, an upper section and a rear section. A left window is in the left side section and a similarly configured right window is in the right side section. A left flap is configured and sized to cover the left window and a similarly configured right flap is configured and sided to cover the right window. A securement assembly selectively retains each flap in a raised orientation above the window or in a lowered orientation covering the window.

A method and apparatus for cutting a window covering comprises saw for cutting the window blind. A clamp assembly moves the window covering relative to the saw. A controller moves the clamp assembly to automatically position the window covering relative to the saw. The saw is moved into engagement with the window covering to cut the window covering.

A gas turbine engine according to an exemplary aspect of the present disclosure includes a windmill pump driven by a spool. A first pump driven by said spool with an air-oil cooler is located downstream of the first pump. A second pump is also driven the spool with an air-air precooler located downstream of the second pump. A method of operating a gas turbine engine during a “windmilling” condition includes driving a windmill pump with a spool during a “windmilling ” condition. A lubricant is communicated to a geared architecture with the windmill pump. A first pump is driven by the spool and an air-oil cooler is located downstream of the first pump.

One embodiment (100) collects air pressure created from forward motion of a motorcycle (300) in a reservoir assembly (1001) which stores a liquid lubricant, is attached to motorcycle frame (302), and comprises a containment chamber (102), cap (106), cap seal (104), air inlet port (107), lubricant outlet port (109), and an air inlet connector (108) and a lubricant outlet connector (110) to facilitate the external attachment of conduit. The air pressure is collected by and delivered to reservoir assembly (100-1) via an air collection conduit (118) attached to motorcycle front portion (306) by a mount (130) and urges liquid lubricant through a suction conduit (124), flow restrictor (112) and delivers lubricant via discharge conduit (114) to a chain applicator (116) attached to a motorcycle swing arm assembly (304) and to the inner circumference of drive chain (310). Lubricant flow ceases after motorcycle is stopped. Other embodiments are described and shown.

A system and method for lubricating gears in a wind turbine blade pitch drive are provided, wherein the pitch drive comprises a drive pinion gear with gear teeth that engage a pitch bearing gear coupled to a respective wind turbine blade. A grease distributor is configured to mount onto and rotate with the pinion gear, and is configured to deliver grease from an external grease supply to at least one valley defined between adjacent teeth of the pinion gear in a contact area of the pinion gear with the bearing gear without the distributor contacting inter-engaging teeth of the bearing gear.

Mounting for a window in an oven appliance is provided so as to allow for thermal expansion during oven use. More particularly, an expansion zone is provided around the window such that, during heating of the window from oven operation, the window is allowed to expand without restraint that could cause cracking or shattering. Space can be allowed for both lateral and longitudinal expansion of the window.

The invention relates to a domestic cooking pot (1) comprising means of controlling (7) at least part of its operation, wherein said control means (7) have a mobile mounting between a plurality of positions, wherein said pot (1) is characterized in that it is further fitted with an information window (8) and at least an indicator (10) that is representative of one of the positions of the control means (7), and in that the window (8), the indicator (10) and the control means (7) work together so that said indicator (10) appears in the window (8) when the control means (7) are in the corresponding position.

A lower thread ending region detection apparatus prevents problems associated with false stitchings occurring from inability to detect lower thread's exhaustion during sewing operation. The lower thread ending region detection apparatus comprises: light control unit, which contacts a part of lower thread wound on a thread bobbin and activates or inactivates at least one of the functions of emitting light, reflecting light, passing light and blocking light, due to the effect of the physical movement force generated depending on whether the lower thread of the ending region is unwound; light receiving unit, which receives the light transferred out by the light control unit and outputs a detection signal; and control and notification unit, which analyzes the detection signal output from the light receiving unit to determine whether the lower thread has reached the ending region and outputs the result to the user.