Abstract: A circular saw includes a housing, a sawing assembly including a motor and a saw blade located at two opposite sides of the housing and connected together so that the saw blasé can be driven by the motor to saw the workpiece and a saw blade shield secured to the housing and covering a part of the saw blade to prevent the saw blade from cutting the surrounding people, and a prism assembly including a protective cover affixed to the front end of the saw blade shield and a prism located in the protective cover to reflect the image of the saw blade sawing the workpiece through a window of the protective cover to the line of sight of the operator. In this way, the operator can clearly confirm whether the sawing path is skewed with the normal operating posture to improve the efficiency.

Abstract: A soft start device for a power cutting machine tool, a control circuit group includes two end, one of which is connected with an input power source and the other is connected with each of two control switches. When the input power source provides a working voltage for the control circuit group, the control circuit group outputs a low-level signal to the control switches to enable a light emitting circuit group to lighting gradually from dark to light, whereby a resistance of a trigger circuit group decreases gradually to make motor setup the working voltage. Next, the control circuit group outputs a high-level signal after a period of time, to turn on the control switches for inputting voltage to the motor directly. The soft start device can not only decrease the noise during activation of the motor but effectively protect the internal components of an electronic device from damage.

Abstract: A folding mechanism operatable between an extended position and a received position is disclosed to include a rack for supporting thereon a table machine, a pair of first legs and a pair of second legs respectively pivoted to the rack for supporting the rack above the floor, two first links respectively pivoted to the rack, two sliding units slidably and respectively sleeved onto the first legs and pivotally and respectively connected with the first links, and two second links respectively pivoted to the sliding units and the second legs. The first and second links and the sliding units are moved with the second legs toward the first legs upon folding the folding mechanism from the extended position to the received position, and at the same time the sliding units are slid along the first legs, assuring safety and stability of the folding action.

Abstract: A folding mechanism operatable between an extended position and a received position is disclosed to include a rack for supporting thereon a table machine, a pair of first legs and a pair of second legs respectively pivoted to the rack for supporting the rack above the floor, two first links respectively pivoted to the rack, two sliding units slidably and respectively sleeved onto the first legs and pivotally and respectively connected with the first links, and two second links respectively pivoted to the sliding units and the second legs. The first and second links and the sliding units are moved with the second legs toward the first legs upon folding the folding mechanism from the extended position to the received position, and at the same time the sliding units are slid along the first legs, assuring safety and stability of the folding action.

Abstract: A brushless permanent-magnet motor includes a stator, a rotor rotatably mounted within the stator in a coaxial manner, a magnet set including a plurality of magnet components mounted around the periphery of the rotor and leaving a gap between the magnet set and the stator, and two locating plates made from a magnetically conductive material and respectively mounted at two opposite sides of the rotor for synchronous rotation with the magnet set and the rotor. Thus, the brushless permanent-magnet motor has a high level of structural stability, and can effectively improve the air-gap flux density and electromagnetic torque under the rated revolving speed to further enhance the performance of the motor.

Abstract: A brushless permanent-magnet motor includes a rotor, a magnet set mounted at the rotor, a stator coaxially surrounding the magnet set in a coaxial manner relative to the rotor, and a bushing set between the magnet set and the stator in a coaxial manner relative to the rotor and the stator. The stator has a plurality of teeth spaced around the inner perimeter thereof and a retaining crevice defined between the distal front end portions of each two adjacent teeth remote from the inner perimeter. The bushing has a plurality of locating ribs respectively engaged into the retaining crevices of the stator. Thus, the brushless permanent-magnet motor has a high level of structural stability, and can effectively reduce the air-gap flux density variation and instant cogging torque and torque ripples and solve vibration and noise problems.

Abstract: A method for aligning Hall sensors location in a brushless DC motor with Hall sensors, the method comprises driving the motor by a sensorless driving system for getting a first commutation phase signal; sending said first commutation phase signal to a sensorless position control unit to be processed thereby for getting an optimal commutation phase point, processing a Hall sensor signal as said motor is running by a Hall sensor circuit unit for getting a second commutation phase signal, and comparing said second commutation phase signal with said optimal commutation phase point by a signal comparing and processing unit to get a phase shifting data for aligning said Hall sensors location.

Abstract: A retaining device for a stand includes a base, a shaft inserted in the base, a handle pivotally mounted on the shaft, and a retainer sleeved on a cam portion of the handle. When the handle is pivotally moved downwards, the retainer can be driven to move toward an extending rod of the stand by actuation of the cam portion of the handle for stopping against the extending rod of the stand and retaining the extending rod of the stand in position.

Abstract: A saw assembly for a table saw includes a bracket, a driving unit swingingly connected with the bracket, a saw blade coupled to a driving shaft of the driving unit, which extends through an inclined guide slot of the bracket, an elevating unit mounted with the bracket and connected with the driving unit, and a shield pivotally mounted between the driving unit and the saw blade. When the driving unit is lifted or lowered by the actuation of the elevating unit, the saw blade can be moved upwards or downwards along the inclined guide slot of the bracket, and the shield can be rotated to keep the inclined slot of the bracket covered, thereby preventing a maintenance worker's hand from getting injured by the saw blade, and allowing the sawing chips of a workpiece to be collected effectively.

Abstract: A rip fence device for a table saw includes two parallel and spacedly arranged rails, two rotating plates pivotally and respectively connected with the rails, and a fence plate pivotally connected between the rotating plates and having a first stop wall and a second stop wall, which are vertical to each other. As a result, when the rip fence device is pulled outwards away from a lateral side of a worktable of the table saw, the lateral edge of a to-be-cut workpiece can be stopped at the second stop wall of the fence plate, and the bottom of the workpiece can be supported by the first stop wall of the fence plate, thereby allowing the workpiece to be firmly supported in the cutting process.

Abstract: A rip fence mechanism for being slidably connected to a worktable of a sawing machine includes parallel and spacedly arranged first and second rails, a fence plate pivotally connected between the first rail and the second rail in a way that the fence plate is pivotable between a vertical posture and a horizontal posture, and a support plate pivotally connected with the fence plate in a way that the support plate is pivotable between a first position where the support plate is abutted with the fence plate and a second position where the support plate is vertical to the fence plate. As a result, the lateral side of a to-be-cut workpiece can be directly stopped at the fence plate at the vertical posture and a bottom of the workpiece can be supported by the support plate at the second position during cutting.

Abstract: A saw blade elevating device for a table saw includes a mounting base, a rotating base pivotally mounted with the mounting base and having two opposite guide slots each extending inclinedly downward, a saw blade unit pivotally mounted with the mounting base and fastened to the rotating base, and a driving unit having a lead screw rotatably inserted in the mounting base, and a guide rod screwed to the lead screw and provided with two ends respectively inserted in the guide slots of the rotating base. When the lead screw is rotated, the guide rod is driven to be moveable between upper and lower dead points of the guide slots of the rotating base for causing a pivotal movement of the rotating base for lifting or lowering the saw blade unit relative to the mounting base.

Abstract: A retaining device for a stand includes a base, a shaft inserted in the base, a handle pivotally mounted on the shaft, and a retainer sleeved on a cam portion of the handle. When the handle is pivotally moved downwards, the retainer can be driven to move toward an extending rod of the stand by actuation of the cam portion of the handle for stopping against the extending rod of the stand and retaining the extending rod of the stand in position.

Abstract: An eye-protection cover quick-release structure includes a spreader, which has a notch and a locating hole at the top side and a contracted passage connected between the notch and the locating hole, a bracket, which has a locating groove for accommodating a part of the spreader and an axle hole, an axle pin, which is insertable through the axle hole of the bracket and the locating hole of the spreader and has a shank and a shoulder, and a handle fastened to the shank of the axle pin and biasable between a pressed position where the shoulder of the axle pin is forced into the locating hole of the spreader to lock the bracket to the spreader and a lifted position where the shank of the axle pin is forced into the locating hole of the spreader and movable through the contracted passage for allowing the bracket to be separated from the spreader.

Abstract: A rotary worktable positioning structure used in a miter saw is disclosed to include a first positioning unit controllable by biasing a handle to lock the worktable to the machine base or to unlock the worktable for free rotation, and a second positioning unit controllable by rotating a switching wheel to move a lock pin into one of a number of locating holes on the periphery of the machine base and to further lock the worktable in one of a number of predetermined cutting angles.

Abstract: A miter saw having a securable positioning structure for a blade guard thereof includes a saw blade, a rotatable handle, a movable blade guard, a control unit, a positioning unit, and a rope. The rotatable handle is provided for the user's holding for the cutting operation. The movable blade guard is shiftable between where it covers the saw blade and where it does not cover the saw blade. The control unit is mounted to the rotatable handle. The positioning unit is provided for blocking the movement of the movable blade guard. The rope is connected with the control unit and the positioning unit. Accordingly, the user only needs to operate the control unit to drive action of the positioning unit via the rope to hold the movable blade guard in position, thus securing the safety of the operation. In addition, the rotatable handle can be turned smoothly without any barrier.

Abstract: A workpiece feeding stopper for use in a stable saw to prevent careless feed of a workpiece having a height greater than a cutting depth of a circular saw blade includes a support arm having a rear end adapted for connection with a spreader of the table saw. A stop member is provided at a front end of the support arm and has a stop face with a bottom edge adapted for being spaced above from a worktable of the table saw by a distance slightly greater than or equal to a cutting depth of the circular saw blade and smaller than a distance between a pivot where a blade guard of the table saw and the spreader are pivotally connected to and the worktable, thereby enabling the workpiece to be completely cut without being stopped by the pivot.

Abstract: A saw blade adjustment structure for table comprises a support rod inserted through a respective arched sliding slot on a front support panel and a rear support panel, a handle pivoted to the front end of the support rod and biasable between a holding down position and a release position, and an adjustment member set between the front support panel and the handle and having an oblong hole coupled to the support rod such that the adjustment member is movable between an initial position and a push-out position subject to movement of the handle between the holding down position and the release position.

Abstract: A quickly detachable spreader mounting structure used in a table saw is disclosed to include a spreader holder, a spreader detachably clamped in the spreader holder, a positioning member inserted through the spreader holder and the spreader and having a positioning portion, and a handle coupled to the positioning member and having a protruding portion and biasable between an unlocking position where the protruding portion is moved away from the positioning portion to release the spreader from the spreader holder and a locking position where the protruding portion is abutted against the positioning portion to lock the spreader to the spreader holder.

Abstract: An eye-protection cover quick-release structure includes a spreader, which has a notch and a locating hole at the top side and a contracted passage connected between the notch and the locating hole, a bracket, which has a locating groove for accommodating a part of the spreader and an axle hole, an axle pin, which is insertable through the axle hole of the bracket and the locating hole of the spreader and has a shank and a shoulder, and a handle fastened to the shank of the axle pin and biasable between a pressed position where the shoulder of the axle pin is forced into the locating hole of the spreader to lock the bracket to the spreader and a lifted position where the shank of the axle pin is forced into the locating hole of the spreader and movable through the contracted passage for allowing the bracket to be separated from the spreader.