Abstract: A bidirectional cross airflow machine tool includes a housing chamber to hold a tool spindle and air inlets and air outlets at two sides thereof. The tool spindle is coupled with a balance weight member which includes a first balance weight portion and a second balance weight portion arranged in an up and down fashion so that the tool spindle generates eccentric rotation against the machine tool. The first and second balance weight portions respectively have a first vane set and a second vane set. The first vane set sucks air via the air inlets at one side of the machine tool during rotation of the tool spindle. The air is transmitted from the first vane set to the first and second balance weight portions, and then is discharged via the second vane set through the air outlets at another side of the machine tool to form cross cooling airflow.

Abstract: An electric power tool receives an input power from an electric power source and converts the input power to a driving power to drive an electric motor. The electric power tool further includes a manual control mechanism, a magnetic control element and a power modulation circuit. The manual control mechanism includes a trigger portion movable by depressing of a user and a magnetic element movable with the trigger portion. The magnetic control element outputs an output control signal in proportion to alterations of a magnetic field caused by movements of the magnetic element. The power modulation circuit gets the input power and modulates to the driving power controlled by the output control signal to drive the electric motor. Thus by depressing the trigger portion, output power of the electric motor can be controlled to provide precise control of rotational speed and torque alterations.

Abstract: A dust-proof machine tool which has a handgrip with an aperture to hold a driving switch movable up and down and a control bar hinged thereon to generate a pivotable stroke to press the driving switch. The handgrip is coupled with a dust-proof cover which has an opening to couple on the driving switch and a press portion formed on the perimeter of the opening to press the handgrip and seal the aperture. Thereby during operation of the machine tool, dust can be prevented from entering the machine tool through the driving switch and the aperture to maintain steady operation of the machine tool and enhance the lifespan thereof.

Abstract: A machine tool providing a large grinding area includes a tool body, a rotary bracket driven by the tool body and a plurality of grinding portions coupled to the rotary bracket. The tool body includes a driving motor and a spindle driven by the driving motor to spin axially. The rotary bracket is coupled to and driven by the spindle to rotate and includes a plurality of connecting portions equally spaced from each other on the circumference formed by rotation of the rotary bracket. The grinding portions are coupled with the connecting portions and have grinding zones at the same horizontal level and are driven by the rotary bracket to rotate synchronously therewith to jointly form a grinding plane. Thereby a larger grinding area can be achieved through smaller grinding discs.

Abstract: A dust collection hood installed on a grinding machine tool which includes a driving motor and at least one grinding portion driven by the driving motor to rotate. The dust collection hood includes a circumferential wall surrounding the grinding portion and a dust collection cap. The dust collection cap is coupled with the circumferential wall to form a dust collection chamber to house the grinding portion, and includes a top fastened to the grinding machine tool. The dust collection chamber is formed at a height gradually decreased from the top towards the circumferential wall. The dust collection cap further includes a dust discharge port communicating with the dust collection chamber and an airflow guiding portion to guide airflow from the dust collection chamber to the dust discharge port. Thus a great amount of dust generated during grinding can be discharged via the dust discharge port.

Abstract: A dust proof structure for a machine tool includes a flow guiding element located therein. The machine tool includes a housing chamber to hold a spindle and the flow guiding element. The housing chamber has an air intake section and an air discharge section communicating with the air intake section. The machine tool further has an air inlet communicating with the air intake section and an air outlet communicating with the air discharge section. The spindle is coupled with an action member outside the air outlet. When the spindle drives the action member to operate, the flow guiding element introduces external air through the air inlet to the air intake section, and directs the air to the air discharge section to be discharged towards the action member. Hence dust generated by the action member during operation of the machine tool does not enter the machine tool through the air outlet.

Abstract: A bidirectional cross airflow machine tool includes a housing chamber to hold a tool spindle and air inlets and air outlets at two sides thereof. The tool spindle is coupled with a balance weight member which includes a first balance weight portion and a second balance weight portion arranged in an up and down fashion so that the tool spindle generates eccentric rotation against the machine tool. The first and second balance weight portions respectively have a first vane set and a second vane set. The first vane set sucks air via the air inlets at one side of the machine tool during rotation of the tool spindle. The air is transmitted from the first vane set to the first and second balance weight portions, and then is discharged via the second vane set through the air outlets at another side of the machine tool to form cross cooling airflow.

Abstract: A negative pressure dust collection structure aims to be used on a power tool which is coupled with an application tool operable in a working space surrounded by a dust collection hood. The dust collection hood includes at least one flow conduction vent communicating with an airflow duct through a negative pressure enhancing duct. The negative pressure enhancing duct has a negative pressure enhancing chamber communicating with the flow conduction vent. The negative pressure enhancing chamber is formed at a cross section shrunk gradually from the flow conduction vent towards the airflow duct to increase suction of the negative pressure enhancing duct to collect dust in the dust collection hood. Moreover, the negative pressure enhancing chamber has an opening edge mating the shape of the inner side of the wall of the dust collection hood to increase covering range of the airflow.

Abstract: A hand-held machine tool with improved output efficiency includes a casing to hold a control circuit connected to a power source and an electric motor which includes a stator, a rotor and an output spindle. The stator has a core and a plurality of stator magnetic poles extended radially. The stator magnetic poles are wound by an exciting winding. The core has an axle hole run through by the output spindle. The rotor has a transmission portion fastened to the output spindle and an induction portion extended from the transmission portion and horizontally corresponding to the stator magnetic poles. The induction portion has a plurality of rotor magnetic poles on an inner rim thereof corresponding to the stator magnetic poles. The rotor magnetic poles and stator magnetic poles are magnetically coupled to induce a magnetic force to drive the output spindle to rotate against the stator in the axle hole.

Abstract: A machine tool with an auxiliary cushion structure includes a machine tool having a grip portion and a trigger switch mounted on the grip portion. The grip portion has a control lever pivotally mounted thereon to enable the control lever to rotate against the grip portion, so as to press the trigger switch during rotation and drive the machine tool to operate. The grip portion further has an auxiliary cushion mounted thereon and a gap is formed between the auxiliary cushion and the control lever. The auxiliary cushion has a supporting surface which is tilted upwards from one end close to the control lever to the other end. Thus no matter the control lever is pressed by the operator or released, the operator's hand can rest on the supporting surface to alleviate or ease the fatigue.

Abstract: A machine tool with a heat conduction structure comprises a machine tool and a heat dissipation seat installed on the machine tool. The machine tool has a handle. The handle has an accommodation space accommodating a circuit board and having an opening at one end. The heat dissipation seat has a heat dissipation member arranged on the opening and a carrying member connected with the heat dissipation member and extended to the accommodation space. The carrying member carries the circuit board, contacts heat sources of the circuit board, and conducts heat to the heat dissipation member. As the machine tool is exempted from forming heat dissipation holes on the handle, the present invention can effectively prevent dust from entering the handle and damaging the circuit board. Further, the present invention can dissipate heat generated by the circuit board and maintain normal operation of the circuit board and the machine tool.

Abstract: A dust-proof switch for a machine tool which has a handgrip with an aperture to hold a driving switch movable up and down and a control bar hinged thereon to generate a pivotable stroke to press the driving switch. The handgrip is coupled with a dust-proof cover which has an opening to couple on the driving switch and a press portion formed on the perimeter of the opening to press the handgrip and seal the aperture. Thereby during operation of the machine tool, dust can be prevented from entering the machine tool through the driving switch and the aperture to maintain steady operation of the machine tool and enhance the lifespan thereof.

Abstract: A heat dissipating architecture for a machine tool is provided. The machine tool includes an accommodating space, a tool shaft mounted in the accommodating space, a counter balancing mass having a first balancing portion and a second balancing portion mounted on the tool shaft for causing an eccentric rotation stroke of the tool shaft, and an inlet communicating with the accommodating space. The heat sink is mounted on the counter balancing mass. The heat sink includes a first blade portion corresponding to the first balancing portion, a second blade portion corresponding to the second balancing portion, and a linking portion for connecting the first and second blade portions, such that during the rotation stroke of the tool shaft, the heat sink inhales air via the inlet, transmit the air from the first blade portion to the second blade portion, and then exhausts the air from the second blade portion.

Abstract: A machine tool with an auxiliary cushion structure includes a machine tool having a grip portion and a trigger switch mounted on the grip portion. The grip portion has a control lever pivotally mounted thereon to enable the control lever to rotate against the grip portion, so as to press the trigger switch during rotation and drive the machine tool to operate. The grip portion further has an auxiliary cushion mounted thereon and a gap is formed between the auxiliary cushion and the control lever. The auxiliary cushion has a supporting surface which is tilted upwards from one end close to the control lever to the other end. Thus no matter the control lever is pressed by the operator or released, the operator's hand can rest on the supporting surface to alleviate or ease the fatigue.

Abstract: A machine tool with a heat conduction structure comprises a machine tool and a heat dissipation seat installed on the machine tool. The machine tool has a handle. The handle has an accommodation space accommodating a circuit board and having an opening at one end. The heat dissipation seat has a heat dissipation member arranged on the opening and a carrying member connected with the heat dissipation member and extended to the accommodation space. The carrying member carries the circuit board, contacts heat sources of the circuit board, and conducts heat to the heat dissipation member. As the machine tool is exempted from forming heat dissipation holes on the handle, the present invention can effectively prevent dust from entering the handle and damaging the circuit board. Further, the present invention can dissipate heat generated by the circuit board and maintain normal operation of the circuit board and the machine tool.

Abstract: A power control structure aims for an electric power tool which gets an input power from an electric power source and converts the input power to a driving power to drive an electric motor. The electric power tool further includes a manual control means, a magnetic control element and a power modulation circuit. The manual control means includes a trigger portion movable by depressing of a user and a magnetic element movable with the trigger portion. The magnetic control element outputs an output control signal in proportion to alterations of a magnetic field caused by movements of the magnetic element. The power modulation circuit gets the input power and modulates to the driving power controlled by the output control signal to drive the electric motor. Thus by depressing the trigger portion, output power of the electric motor can be controlled to provide precise control of rotational speed and torque alterations.

Abstract: A heat dissipation structure for sealed machine tools includes a motor rotor rotating to drive airflow to perform heat dissipation simultaneously. It includes a machine tool housing with a heat dissipation vent and a chamber inside, a stator in the chamber and a rotor located between the stator and the housing. The rotor and the housing wall form a swirling flow space between them. The rotor and the stator form an axial flow space between them. The swirling flow space and the axial flow space communicate through a radial airflow passage. The rotor has at least one flow directing portion. The rotor rotates relative to the stator. The stator generates thermal airflow which flows from the axial flow space through a radial airflow passage to the swirling flow space. The flow directing portion performs an exchange of cooling air and thermal airflow through the heat dissipation vent.

Abstract: A negative pressure dust collection structure aims to be used on a power tool which is coupled with an application tool operable in a working space surrounded by a dust collection hood. The dust collection hood includes at least one flow conduction vent communicating with an airflow duct through a negative pressure enhancing duct. The negative pressure enhancing duct has a negative pressure enhancing chamber communicating with the flow conduction vent. The negative pressure enhancing chamber is formed at a cross section shrunk gradually from the flow conduction vent towards the airflow duct to increase suction of the negative pressure enhancing duct to collect dust in the dust collection hood. Moreover, the negative pressure enhancing chamber has an opening edge mating the shape of the inner side of the wall of the dust collection hood to increase covering range of the airflow.

Abstract: A dust proof structure for a machine tool includes a flow guiding element located therein. The machine tool includes a housing chamber to hold a spindle and the flow guiding element. The housing chamber has an air intake section and an air discharge section communicating with the air intake section. The machine tool further has an air inlet communicating with the air intake section and an air outlet communicating with the air discharge section. The spindle is coupled with an action member outside the air outlet. When the spindle drives the action member to operate, the flow guiding element introduces external air through the air inlet to the air intake section, and directs the air to the air discharge section to be discharged towards the action member. Hence dust generated by the action member during operation of the machine tool does not enter the machine tool through the air outlet.

Abstract: A heat dissipating architecture for a machine tool is provided. The machine tool includes an accommodating space, a tool shaft mounted in the accommodating space, a counter balancing mass having a first balancing portion and a second balancing portion mounted on the tool shaft for causing an eccentric rotation stroke of the tool shaft, and an inlet communicating with the accommodating space. The heat sink is mounted on the counter balancing mass. The heat sink includes a first blade portion corresponding to the first balancing portion, a second blade portion corresponding to the second balancing portion, and a linking portion for connecting the first and second blade portions, such that during the rotation stroke of the tool shaft, the heat sink inhales air via the inlet, transmit the air from the first blade portion to the second blade portion, and then exhausts the air from the second blade portion.