Abstract: A gear module includes a rotating cylinder, a first planetary gear set, a second planetary gear set, a concave-convex structure, and a limit bearing set. The first planetary gear set is accommodated in the rotating cylinder and includes a driven gear; the second planetary gear set includes a positioning frame, second planetary gears pivoted to a positioning frame, a driven gear engaged with the second planetary gears, and the positioning frame has a through hole; the concave-convex structure includes a convex column extended from the rotating cylinder and a concave hole formed on the positioning frame, the convex column is plugged into the concave hole; the limit bearing set includes a first ball bearing sheathing the driven gear and mounted between the driven gear and the through hole, and a second ball bearing sheathing the convex column and mounted between the convex column and the concave hole.

Abstract: A low rotational speed gear module includes a fixed tube member, a rotational sleeve, a first planetary gear set, a sun gear, and a second planetary gear set. The fixed tube member includes a first inner gear. The rotational sleeve includes a second inner gear. The first planetary gear set includes a fixing plate, first planetary gears fixed to one side of the fixing plate, and a driven gear fixed to the other side of the fixing plate. The first planetary gear is engaged at one side with the sun gear and engaged at another side with the first inner gear. The second planetary gear set includes second planetary gears. The second planetary gears is engaged at one side with the driven gear and engaged at another side with the first inner gear and the second inner gear.

Abstract: A low rotational speed gear module includes a fixed tube member, a rotational sleeve, a first planetary gear set, a sun gear, and a second planetary gear set. The fixed tube member includes a first inner gear. The rotational sleeve includes a second inner gear. The first planetary gear set includes a fixing plate, first planetary gears fixed to one side of the fixing plate, and a driven gear fixed to the other side of the fixing plate. The first planetary gear is engaged at one side with the sun gear and engaged at another side with the first inner gear. The second planetary gear set includes second planetary gears. The second planetary gears is engaged at one side with the driven gear and engaged at another side with the first inner gear and the second inner gear.

Abstract: A gearbox of an electrical drill is disclosed. The drill has a main shaft and the gear box comprises a torque mechanism having an adjusting element mounted onto the main shaft and a driving element mounted within the housing, a plurality of pegs being slide-mounted onto the adjusting element and the rotating housing linked to the adjusting element to provide a displacement and the plurality of pegs engaged with the driving element to prohibit the driving element from rotating; and a vibration switching mechanism having a switching element mounted onto the main shaft and a pad mounted within the rotating housing inserted with two pegs, and the rotating housing being capable of driving the pad to rotate the switching element, and the switching element matched with the securing peg so that the main shaft has an axial displacement.

Abstract: A dual positioning shift-adjustment structure of the gear case of electrical tools is provided. The dual positioning shift-adjustment structure contains a spring band structure and a spring steel beads structure, which make accurate, precise, and no-gap position of the gearshift. It makes shift-positioning of the torque-driven electrical tool a perfect operation and improves both operational life and quality of end products of electrical tools.

Abstract: A structure for enhancing torque output of an electric drill includes a torque output unit mounted in an inner housing of a torque control unit. The torque output unit includes an intermediate washer located between an internal gear and a locating gear ring to isolate other components behind it from any backward transmitted reaction force that is generated when the electric drill operates, making it possible to use economical plastic instead of expensive powder metallurgic locating gear ring and pinions, and to snap-fit instead of screwing a motor bedplate to a rear end of the inner housing. The locating gear ring is provided with stop lugs to engage with open recesses provided on the inner housing and the internal gear, preventing slippage of the torque output unit in the inner housing even at a large torque output.

Abstract: An automatic output shaft locking mechanism for electric tools, and particularly a locking mechanism in which the output shaft is driven by electric power and will automatically lock in position when it is turned by an external force, including a retaining end with three equi-angular projections at one end of the output shaft in the tool, and a rotary disk having three equi-angular notches at an outer side. The outer portion of the rotary disk is fitted with a securing ring, and its three notches receive lock rollers respectively. When the retaining end turns, the three projections will push the lock rollers to engage the securing ring so that the output shaft is locked in position.