Abstract: There is disclosed a sagittal saw blade mount and corresponding sagittal saw blade. The blade mount is configured to rotationally oscillate along a plane of motion about an axis of rotation which passes through the blade mount crossing the plane of motion at a point of rotation. The blade mount comprises a securing portion comprising two securing faces passing through the plane of motion and a locking member configured to urge a blade towards the securing portion in a first direction parallel to the plane of motion, thereby securing the blade between the locking member and the securing faces. The two securing faces are angled such that the planes of the securing faces intersect with each other and with the plane of motion at a point of intersection which is positioned such that the point of rotation lies between the point of intersection and the securing portion.

Abstract: A depth restrained cutting device for preventing unintended contact with live wires includes a plate that is rigid. The plate is configured to couple to a cutting tool. A cutting edge is coupled to and extends radially from a circumference of the plate. A stop is coupled to a first face of the plate. The stop is dimensionally smaller than the plate. The stop is configured to contact a surface of a substrate that is to be cut, such as a polyvinyl chloride pipe, to prevent contact of the cutting edge with articles, such as wires, that are positioned in the substrate.

Abstract: What is disclosed is a blade core for attachment with an endless chain assembly. The blade core is a generally circular disc having two opposing faces and a width between the faces. The blade core has a circumferential groove extending inward from the circumference of the blade core such that the drive links, or the tang of the drive links, extends from the chain located on the circumference of the circular disc inward in said groove. Ideally the width of the groove is proximate to the width of the drive link such that friction between the sides of the groove and the drive link prevent the chain from rotating along the circumference of the circular disc when the blade core and endless chain assembly are rotating to cut a material. Ideally the base of tie-strap-tie strap and tie strap-cutter assembly is the same as width of the rail to restrict lateral movement.

Abstract: A controller of a gear cutter machining apparatus includes a rotation control unit and a movement control unit. The rotation control unit rotates a gear cutter about a central axis of the gear cutter, and rotates a grinding wheel about a central axis of the grinding wheel. The movement control unit gradually changes a crossed axes angle when relatively moving the grinding wheel in a direction of the central axis of the gear cutter, and moves the grinding wheel in a translating direction that is a rotational tangent direction of the gear cutter.

Abstract: An electric discharge machine includes an electrode, a shaft-feed driving unit that, a voltage/current applying unit, a shaft-feed control unit that causes the shaft-feed driving unit to perform a jump operation, and a machining-condition setting and changing unit that sets a voltage applied between the electrode and a workpiece and an electric current flowing between the electrode and the workpiece. The machining-condition setting and changing unit determines whether the electric discharge between the electrode and the workpiece stabilizes after the jump operation ends and, in at least a part of a period before determining that the electric discharge stabilizes, sets at least one of the voltage and the electric current to a condition in which electric discharge more easily occurs than in the condition in applying the electric discharge machining.

Abstract: A soldering method includes intermittently ejecting a solder jet to a workpiece from a jet nozzle, and spraying gas on an outer side surface of the jet nozzle when stopping ejection of the solder jet from the jet nozzle. And a soldering apparatus includes a first nozzle from which a solder jet is intermittently ejected to a workpiece, and a second nozzle from which gas is sprayed on an outer side surface of the first nozzle.

Abstract: A method for welding two or more conduits includes aligning end portions thereof in an abutting relationship to define a gap. The method includes performing a spatter free root weld along the gap to configure a root layer while the inner circumferential surface side is unobstructed. After the root weld is complete, an outward thrust is applied along the inner circumferential surfaces of the conduits. During the application of the outward thrust, a filler weld is performed along the gap to fill the gap and to facilitate shrinkage of the filler and root weld materials longitudinally and radially outward while preventing pressing out of the filler and root weld materials radially inward of the inner circumferential surface.

Abstract: A method for nondestructive inspection of the weldability of a component manufactured by pressure-die-casting, especially by vacuum-assisted pressure-die-casting component, from an aluminum alloy. Using a TIG welding machine, a weld seam of specified length is produced, in an automated process with welding parameters to be predetermined and maintained constant, on the component. The surface of the component is then assessed visually for weldability on the basis of specified features.

Abstract: A welding system includes a welding wire feeder, and the welding wire feeder includes a motor and an adjustable drive shaft assembly. The motor is and configured to rotate a feed roll with respect to the wire drive assembly housing. The adjustable drive shaft assembly is coupled to the motor and configured to couple with the feed roll. The adjustable drive shaft assembly includes a drive mechanism configured to urge rotation of the feed roll and to adjust a position of the feed roll relative to the wire drive assembly housing.

Abstract: A gas-shielded arc welding method includes feeding a consumable electrode via a welding torch and performing welding while flowing a shielding gas. The welding torch includes a nozzle. An inner diameter of the nozzle is 15 mm or more. A nozzle-base material distance between a tip of the nozzle and a material to be welded is 22 mm or less. A ratio expressed by (the inner diameter of the nozzle/the nozzle-base material distance) is 0.7 or more and 1.9 or less.

Abstract: A swing arm assembly is provided for a spot welding machine. The swing arm assembly can accommodate a tip dresser or a tip exchanger and can include a lift assembly that can translate the tip dresser from a first position to a second position along a lateral axis.

Abstract: A method of using friction stir processing to repair a defect in a pre-existing weld of a pipeline of steel or other ferrous alloy. The method comprises attaching run-on and run-off tabs to the pipeline on respective sides of the defect and then advancing a friction stir processing tool into the nm-on tab. The tool is moved from the nm-on tab to the run-off tab along a weld-processing path that incorporates the defect. Once the defect is repaired, the tool is removed from the run-off tab. The run-on and run-off tabs may then be removed from the pipeline. The nm-on and nm-off tabs are generally wedge-shaped, each comprising an inner seating face and an outer running face that converges with the inner seating face. When attached to the pipeline, the tabs toward each other about the circumference of the pipeline.

Abstract: A technique for joining parts of incompatible metals involves cold spraying a 150-900 micron thick layer of a metal compatible with the second part onto the first part, and friction stir joining the parts by lap welding while keeping a tool of the FSJ tool at least 300 microns away from the first part (less layer) throughout the joining, to avoid damaging the cold spray to first part interface, and formation of intermetallics. Improved fatigue resistance is shown. A sealant can advantageously further improve fatigue resistance.

Abstract: A temperature sensor is provided inside the protrusion portion of the welding tool, and when welding is performed, the control device controls a rotation speed, a movement speed, or both rotation speed and movement speed of the welding tool, and thus the temperature detected by the temperature sensor is managed so as to fall within the predetermined management temperature range, and welding quality is equalized.

Abstract: The invention relates to a device and to a method for homogeneously welding two-dimensionally bent structures by friction stir welding.

Abstract: A method for laser processing a transparent workpiece includes forming a contour line having defects in the transparent workpiece, which includes directing a pulsed laser beam oriented along a beam pathway through a beam converting element and through a phase modifying optical element such that the portion of the pulsed laser beam directed into the transparent workpiece includes a phase shifted focal line having a cross-sectional phase contour that includes phase contour ridges induced by the phase modifying optical element and extending along phase ridge lines. Moreover, the phase shifted focal line generates an induced absorption within the transparent workpiece to produce a defect within the transparent workpiece including a central defect region and a radial arm that extends outward from the central defect region in a radial defect direction oriented within 20° of the phase ridge lines of the phase shifted focal line.

Abstract: The laser welding method according to the present disclosure has a first step for forming a weld bead by irradiating an object to be welded with a laser beam along a first helical trajectory around a first center of rotation moving in a welding direction, and a second step for irradiating the object to be welded with a laser beam along a second helical trajectory around a second center of rotation moving in the welding direction. A diameter of rotation of the laser beam in the first step is larger than a diameter of rotation of the laser beam in the second step.

Abstract: A machining system includes a laser irradiation device, a camera that captures an image of a workpiece, and a display that displays the image captured by the camera. The machining system includes a robot control device that controls the camera and the display. The camera captures the image of the workpiece before machining. The robot control device calculates a laser-beam irradiation position on the workpiece and virtually displays the laser-beam irradiation position on the display so as to overlap the workpiece image captured by the camera.

Abstract: A method for filamentation of a dielectric workpiece has a workpiece with a thickness between 0.5 and 20 mm is provided. The workpiece has boundary surfaces delimiting the workpiece. The thickness of the workpiece varies spatially and/or at least one of the boundary surfaces delimiting the workpiece has at least one curvature with a radius of curvature between 0.1 ?m and 10 m. The dielectric workpiece can have a specially formed edge.

Abstract: A cover includes a base plate, an orbital disc, a plate slide and a disc slide. The cover is configured for positioning over an opening of a light-tight enclosure. The base plate includes an aperture, a bore and a slot defined therein. The base plate is configured to engage the enclosure. The orbital disc includes an aperture defined therein, a wall disposed adjacent the aperture, and a slot defined therein. The orbital disc is configured to at least partially engage the bore of the base plate. The plate slide is configured to slidingly engage the slot of the base plate. The disc slide is configured to slidingly engage the slot of the orbital disc.

Abstract: An aluminum alloy for heat exchanger applications and a method for fabricating a billet comprising the aluminum alloy are disclosed. The aluminum alloy includes an amount of silicon between 0.01 and 0.08 wt %; an amount of iron between 0.03 and 0.12 wt %; an amount of manganese 0.50 and 0.90 wt %; an amount of titanium 0.1 and 0.15 wt %; an amount of zinc between 0.05 and 0.10 wt %; no more than 0.03 wt % copper; no more than 0.008 wt % nickel; no more than 0.03 wt % other impurities; and a balance of aluminum. The ratio of iron and silicon to manganese ranges from 0.044 to 0.40, and the total wt % of zinc and titanium is between 0.15 and 0.25 wt %. Fabrication of the billet includes heating and soaking the billet to a temperature between 575° C. and 625° C. and cooling the billet to 350° C. at a controlled rate between 100° C. and 225° C. per hour.

Abstract: Provided herein are embodiments of an aluminium composite material for use in thermal flux-free joining methods. The composite material includes at least one core layer having an aluminium core alloy and at least one outer solder layer of an aluminium solder alloy. The aluminium solder alloy has the following composition in wt %: 6.5%?Si?13%, Fe?1%, 90 ppm?Mg?300 ppm, Bi?500 ppm, Mn?0.15%, Cu?0.3%, Zn?3%, and Ti?0.3% with the remainder Al and unavoidable impurities individually at most 0.05%, in total at most 0.15%. The aluminium solder layer has an alkaline pickled or acid pickled surface. Embodiments also relate to a method for producing an aluminium composite material, a method for the thermal joining of components, and a thermally joined construction.

Abstract: Provided is an Au-based solder alloy that has high bonding reliability even when its Au content is lower than that of a conventional Au-based solder alloy. The Au-based solder alloy is used for sealing or bonding a ceramic electronic component and made of an Au—Sn—Ag alloy containing 21.1 to 43.0% by mass of Sn, 0.1 to 15% by mass of Ag, and a balance of Au and inevitable impurities, an Au—Ge—Sn alloy containing 9.5 to 15% by mass of Ge, 2 to 10% by mass of Sn, and a balance of Au and inevitable impurities, or an Au—Ag—Ge alloy containing 5 to 18% by mass of Ag, 7 to 20% by mass of Ge, and a balance of Au and inevitable impurities. When the Au-based soldering ball is crushed in one direction, a maximum stress before cracking occurs is 2.0×102 N/mm2 or more, and a square root of strain before the cracking occurs is 0.40 or more.

Abstract: The present invention concerns a process for the manufacture of flux compositions, flux compositions obtainable by the process according to the invention, aluminum or aluminum alloy parts at least partially coated with the flux composition manufactured by the process, and a brazing process and brazed metal object obtainable by said process.

Abstract: One or more techniques and/or systems are disclosed for an agglomerated welding flux that can comprise, as expressed in % by weight of flux: 25 to 35% MgO, 20 to 28% CaF2, 15 to 22% Al2O3, 12 to 17% SiO2, and 0,2 to 0,4% carbon (% by weight). The carbon can be introduced using at least one metallic compound contained in the flux. Further disclosed is a process for submerged-arc welding of at least one workpiece made of austenitic stainless steel, using the described flux. Additionally disclosed is a welded joint that can comprise 17 to 20% Cr, 5 to 8,5% Mn, and 14 to 18% Ni, which can be obtained using the described process.

Abstract: Disclosed is a workpiece receptacle, in particular for an ultrasonic welding device, that has a receiving element for receiving a workpiece. The receiving element can be moved in relation to a base element. A bearing device disposed between the receiving element and the base element for this purpose. The bearing device has spherical surfaces lying opposite one another.

Abstract: A method to repair an opening in a metallic device including: mount the device on a positioner; while the device is mounted on the positioner, sense and record positions of a surface of an opening in the device using a probe operated by a manipulator; based on the recorded positions determine a centerline and diameter of the opening; orient a digital model of the opening with respect to the opening of the device based on the centerline and diameter of the opening, and apply an weld or cladding to the opening by a welding torch maneuvered automatically by the manipulator while the device is mounted to the positioner and based on the oriented digital model of the opening.

Abstract: A method for reducing leakage through a defect area of a reactor component (or other workpiece), apparatus for performing the method, and product formed therefrom are disclosed. The method includes forming first and second spot material portions on the reactor component by friction-sealing first and second parts of a consumable structure to first and second positions of the reactor component. The friction-sealing includes pressing the consumable structure against the first and second positions of the reactor component while using a machine to rotate and/or oscillate the consumable structure, and moving the consumable structure away from the reactor component in between the forming the first and second spot material portions. The first and second positions of the reactor component are different and include a portion of the defect area. At least one of the first and second spot material portions overlaps the portion of the defect area.

Abstract: A method for determining the elongation and/or compression of a profiled sealing element applied to a body includes drawing the profiled sealing element, which exists as an endless profiled element, from a store and, with the help of an application roller and by means of an adhesive surface present on the profiled sealing element, rolling the profiled sealing element onto the body part along a line intended for the attachment. A measuring roller, which rolls on the profiled sealing element without slip, is arranged at a small distance before a drive system for the profiled sealing element. The length sensed by the measuring roller corresponds to the length of the profiled sealing element applied to the body along an application distance having a defined length.

Abstract: This tool exchange device for a machine tool uses an exchange arm to exchange tools between a processing area and a tool accommodation area which are partitioned by a partition wall provided with an opening and a shutter capable of opening and closing the opening. In the tool exchange device, an imaging device is used to capture an image of a tool in the tool accommodation area, the length of the tool is calculated from the captured image of the tool, the opening width of the shutter is determined in accordance with the length of the tool, and the shutter is opened to the determined opening width.

Abstract: A machining unit including at least one machining module. The machining module includes a protective compartment that delimits an enclosure and has a front door, which can go from a closed position to an open position defining an opening. A machining assembly is provided with a tool-holder and a part-holder. A movable carriage receives the machining assembly and can slide on a guide device, between a first position in which the machining assembly is accommodated in the enclosure and a second position in which the carriage projects from the protective compartment via the opening and the machining assembly is situated outside the enclosure. In the first position, the front door can be closed for the purpose of carrying out machining of a part by the machining assembly. The second position permits access to the machining assembly from the exterior of the protective compartment.

Abstract: System for machining workpieces including a setting-up module and a machining module for the production of components. The setting-up module includes at least one first tool holder fixing device for fixing at least one tool holder removably, and at least one first workpiece support fixing device for fixing a workpiece support removably. The machining module includes at least one second tool holder fixing device for fixing at least one tool holder removably and at least one second workpiece support fixing device for fixing a workpiece support removably, such that the tool holder and the workpiece support can both be transferred from the setting-up module to the machining module after setting up.

Abstract: A tool for chamfering cleaved tips of optical fibers. The tool including conical bores of relatively smooth and hard material terminate at a cylindrical bore that is slightly larger than the fiber core maximum diameter and a fiber centering bore that is slightly larger than the fiber coating maximum diameter. The tool provided such that when a cleaved fiber tip is inserted into the centering bore the sharp edge falls upon the chamfer that, when rotated relative to the fiber, gently grinds the edge to the chamfer angle. Chamfering cannot occur on the core face due to the absence of tool surface at this dimension.

Abstract: An abrasive belt grinding center applicable to grinding and polishing of a whole profile of a blisk is provided, an X-axis feed mechanism, a Y-axis feed mechanism, a Z-axis feed mechanism, a B-axis rotation mechanism and a C-axis rotation mechanism constitute a grinding head feed mechanism, and a housing, a drum, a synchronous driven pulley, a synchronous belt, a synchronous driving pulley, and a grinding head rotation driving motor constitute a grinding head rotation mechanism. In the present application, two grinding heads are utilized to reasonably assign the machining angle and the feeding, and rough machining and fine machining can be both realized by one time of clamping, and the combination of six degrees of freedom in space is achieved by a short drive chain, and further the rigidities of a grinding head mechanism and a workpiece clamping mechanism are ensured.

Abstract: A polishing apparatus polishes a surface of a substrate by pressing the substrate against a polishing pad on a polishing table. The polishing apparatus is configured to control a temperature of the polishing surface of the polishing pad by blowing a gas on the polishing pad during polishing. The polishing apparatus includes a pad temperature control mechanism having at least one gas ejection nozzle for ejecting a gas toward the polishing pad and configured to blow the gas onto the polishing pad to control a temperature of the polishing pad, and an atomizer having at least one nozzle for ejecting a liquid or a mixed fluid of a gas and a liquid and configured to blow the liquid or the mixed fluid onto the polishing pad to remove foreign matters on the polishing pad. The pad temperature control mechanism and the atomizer are formed into an integral unit.

Abstract: The present invention provides a polishing apparatus including: a turntable which has a polishing pad attached thereto; a polishing head configured to hold a wafer; a tank configured to store a polishing agent; a polishing agent supply mechanism which supplies the polishing agent stored in the tank to the polishing pad; a waste liquid receiver which collects the polishing agent flowing down from an upper side of the turntable; and a circulation mechanism which is connected to the waste liquid receiver and supplies the polishing agent collected by the waste liquid receiver to the tank, the polishing agent is supplied to the polishing pad from the tank by the polishing agent supply mechanism, the used polishing agent which flows down from the upper side of the turntable is collected by the waste liquid receiver, a surface of the wafer held by the polishing head is rubbed against the polishing pad so that it is polished while supplying the collected polishing agent to the tank to circulate the polishing agent, a

Abstract: CMP pad dressers having leveled tips and associated methods are provided. In one aspect, for example, a method can include pressing a CMP pad dresser against a CMP pad, where the dresser includes a monolayer of a plurality of superabrasive particles protruding from a matrix layer. The difference in protrusion distance between the highest protruding tip and the second highest protruding tip of the monolayer of superabrasive particles is less than or equal to about 10 microns and the difference in protrusion distance between the highest 10 protruding tips of the monolayer of superabrasive particles are within about 20 microns or less. The method can further include rotating the dresser against the CMP pad such that asperities are cut into the CMP pad having a maximum cutting depth of about 60 microns.

Abstract: A method and apparatus are provided for coupling a first and second wheeled vehicle. The apparatus includes a first area with a stop to engage an undersurface of the first wheeled vehicle and a second area with spaced apart openings to receive wheels of the second vehicle. The apparatus also includes a hook member positioned between the first and second areas and including surfaces to engage a perimeter of the frame of the first wheeled vehicle. The method includes engaging a perimeter of the frame of the first wheeled vehicle with the hook member. The method further includes rotating the stop about an engagement point between the hook member and the frame of the first wheeled vehicle until the stop engages an undersurface of the frame. The method further includes positioning a pair of wheels of the second vehicle in the spaced apart openings.

Abstract: The invention relates to an electric hand-held tool with a tool mount, a motor for driving a tool fastened in the tool mount, and a housing which includes a handle area, a motor area for accommodating the motor, and in which vent openings are configured for the ventilation of the motor. At least in the area of the vent openings, the housing is provided with at least one cover with a closed surface, said cover sitting flush against the housing with an edge area facing the tool mount, being arranged at a distance from the housing in an area above the vent openings, and leaving a gap between the cover and the housing in the area of its edge area facing away from the tool mount.

Abstract: A method for cleaning using solid carbon dioxide is provided. Adhesive surfaces of the vehicle components are cleaned automatically in an assembly line including several work stations. The adhesive surfaces of the vehicle components may be adhesive surfaces of coated or painted vehicle components. The vehicle components may be composed of a metal alloy such as a steel or aluminum alloy, and/or composed of a fiber composite material such as carbon-fiber-reinforced plastic. The adhesive surfaces of the vehicle components may be cleaned with specifically adapted cleaning parameters.

Abstract: A device for cleaning adhesive surfaces of vehicle components using solid carbon dioxide is provided. The device may be used for automated cleaning in an assembly line with a plurality of work stations. The device includes a chamber-type cleaning area for vehicle components, a blasting device with a jet nozzle for emitting solid carbon dioxide onto the vehicle components, a transport device for transporting the vehicle components through the cleaning chamber, and a charge discharge device for discharging an electrostatic charge from the vehicle components in order to structurally and/or functionally improve the device.

Abstract: A method for determining sufficiency of compressive residual stresses in region below cold worked surface covered by a polished surface. Method includes obtaining surface height data along scanning passes over unpolished surface of the cold worked surface and the polished surface, determining region of surface height data with low and high points, and calculating step height by calculating difference between low and high points. Determining average height of the polished surface and peak height of the unpolished surface for the low and high points respectively. Cold worked surface may be peened surface. Confocal scanning microscope may be used for obtaining surface height data. Method may be used for qualifying a cold working or peening and polishing process for an airfoil which may include at least one feature from group consisting of camber, twist, curve away from the span, and lean away from the span.

Abstract: A part processing apparatus and method is disclosed that includes a media-blasting apparatus and a cleaning apparatus. The media-blasting apparatus is configured to blast a stream of media against a surface of a part, and the cleaning apparatus is configured to clean debris or particles from the surface of the part. The cleaning apparatus includes a first spray-and-wash unit, a first ultrasonic wash unit, a second ultrasonic wash unit, and a second spray-and-wash unit. The first ultrasonic wash unit is configured to ultrasonically vibrate a liquid in the first ultrasonic wash unit at a first frequency, and the second ultrasonic wash unit is configured to ultrasonically vibrate a liquid in the second ultrasonic wash unit at a second frequency. The first and second frequencies may be different from each other, such that vibration at the second frequency causes additional debris or particles to be removed from the surface of the part.

Abstract: A wet blast machine for cleaning or preparing surfaces comprises: a treatment source for providing a pressurised mixture of treatment material; a nozzle, the nozzle comprising: an inlet for receiving the pressurised mixture of treatment material; an outlet for ejecting the pressurised mixture; and at least one hole in a wall of the nozzle, the hole for feeding one or more products into the nozzle such that one or more surfaces of the product are exposed to the treatment material whilst within the nozzle, allowing for a more efficient wet blast of the products.

Abstract: A handheld skate blade sharpening tool that has an automatically indexing, rotating sharpening stone that matches the concaved profile of the skate blade retained within a two-piece body member. Screws hold the two-piece body member together to keep the round sharpening stone sized to match the desired concave profile. The sharpening stone will remove metal to match the shape of the stone each time the sharpener is moved back and forth along the blade. The sharpening stone has gears on each end of the stone that match the gears inside the two-piece body. As the tool is moved along the skate blade, the sharpening stone will incrementally rotate within the body when the direction is changed in the reciprocating motion by the user's back and forth movement.

Abstract: A pliers includes a first member and a second member pivotally coupled to the first member. The first member and the second member each include a head and a handle having a recessed area with a non-circular cross-sectional shape and an exposed end portion adjacent the recessed area. The recessed area is bounded by a forward lip and a rear lip. The forward lip has a cross-sectional area not greater than a cross-sectional area of a portion of the handle adjacent the forward lip and opposite the recessed area. The pliers also includes a first grip positioned on the recessed area of the handle of the first member and a second grip positioned on the recessed area of the handle of the second member. The end portions of the handles are made of metal.

Abstract: An open end wrench includes a body having a jaw portion for holding a workpiece. The jaw portion includes an arcuate sliding groove, an expanding groove, and a slider movable relative to the arcuate sliding groove along an arcuate path. The jaw includes a first jaw having a force-applying face and an evasive portion adjacent to the force-applying face. When the jaw portion deforms elastically while wrenching the workpiece, the expanding groove increases the expanding effect within an elastic limit of the jaw portion, such that a corner between the force-receiving face in a first rotating direction and a sixth force-receiving face in a second rotating direction can move across the force-applying face into the evasive portion, avoiding damage to the slider and the first jaw resulting from failure in withstanding the reactive force from the workpiece. Thus, the open end wrench has high toughness and a long service life.

Abstract: A ratchet wrench includes a body, a ratchet wheel, a pawl, a switch unit, a ring, a top clip and a bottom clip. The body includes a through hole, a first recess, a second recess, a top recessed area and a bottom recessed area to accommodate the ratchet wheel, the pawl, the switch unit, the ring, the top clip and the bottom clip. The ratchet wheel has a first pivotal portion, a top groove, a second pivotal portion and a bottom groove. The pawl has a notch. The switch unit is pivoted to control the movement of the pawl in the first recess. The ring is located in the top recessed area and has a fourth pivotal portion connected to the first pivotal portion. The top clip and the bottom clip respectively clip two ends of the ratchet wheel to restrict the ring and the ratchet wheel.

Abstract: A hand tool comprises a handle having a central area having a lower end and an upper end and a pair of outwardly extending arms at the upper end, and a shaft having a fixed end connected to the lower end of the central area and an open opposite end for receiving a tool bit. A ratchet mechanism is formed between the shaft and the central area to control rotational movement of the shaft. A ring is releasably mounted on the shaft and capable of limited movement relative to the shaft.

Abstract: A power tool includes a motor disposed in a motor housing, a handle extending downward from the motor housing, a main switch provided on the handle and configured to switch the motor ON and OFF, and a state-changing operation part located on a lower portion of the motor housing or on an upper-end portion of the handle. The state-changing operation part is located upward of the main switch and is configured to effect a change of a rotational state of the motor, other than a direction of rotation of the motor, or an illumination level of a light.