A screw driving device includes: a case; a motor provided with a rotor; an output member capable of driving in rotation an element for driving an element to be screwed; a transmission connecting the rotor to the output member, the transmission including at least one additional gear train capable of being engaged/disengaged; an motor controller. The device includes an element for engaging the additional gear train, which is capable of being in at least: an engagement state in which the additional train is engaged, and a disengagement state in which the additional gear train is not engaged. A reduction ratio of the transmission between the rotor and the output member is different according to whether or not the additional gear train is engaged, the reduction ratio being greater when the additional gear train is engaged.

A ratchet tool provided, including: a driver body, including a handle and a working rod connected with the handle, at least one of the handle and the working rod being integrally formed with a first blocking structure; at least one sleeve member, being disposed around and unidirectionally rotatable about the driver body, integrally formed with a second blocking structure, at least one of the first and second blocking structures being configured as a ratcheting structure, the second blocking structure being releasably stuck with the first blocking structure in a rotation direction; wherein when there is a relative torque greater than a predetermined torque between the at least one sleeve member and the driver body, at least one of the first blocking structure and second the blocking structures deforms and the second blocking structure is slidable over the first blocking structure in the rotation direction.

Disclosed are aspects of exemplars of torque-limiting devices, methods and mechanisms. Exemplary methods may include placing an actuator in a tool containment interface of a handle, the interface being fluidly connected to an adjustment interface and adjustable via a fixation fastener; movably mounting a tool portion with an actuation catch and a work piece engaging region (WER) in the interface; applying sufficient force to the movable mounting to the handle may be via pins, guides and slots. Said catch may be one of a body catch and a lever catch; and, the actuator terminates on one of a ball shaped end that forms an interface with the body catch and a force lever that forms an interface with the lever catch.

A torque structure includes a first body, a second body, a first elastic member, a third body, and a limit unit. The second body is provided with a second receiving chamber, a first pivot portion, at least one first positioning portion and at least one second positioning portion. The first elastic member is received in the second receiving chamber. The third body is provided with a drive portion, a pivot seat, a second pivot portion, and a first limit portion. The limit unit is assembled with the second body and the third body and rotated between a disengaging position where the third body is unlocked from the second body and has a torque slip function relative to the second body, and a engaging position where the third body is locked by the second body and does not have a torque slip function.

A setting torque tool to tighten a screw or a similar fastener to a target torque is disclosed. The torque tool comprises a main body with a housing and a drive shaft, which is firmly attached to the housing to transfer a torque. The drive shaft has a connection area, to which a drive can be connected. An adapter for an operating tool rotates together with the housing and the drive shaft to transfer the torque, Sensor measure and evaluate the torque transferred. A release mechanism, which is arranged in the housing, releases the torque tool upon reaching a target torque.

An integrated disposable rotational speed reduction assembly having a shaft assembly, a housing, an output assembly, and a plurality of planetary gears each having a plurality of gear teeth. The shaft assembly is configured to cause rotation of the planetary gears with a sun gear. The rotation of the planetary gears is configured to cause rotation of an output shaft, with a reduction of rotational speed relative to the rotation of the shaft assembly.

A torque limiter can include a housing and a shaft. The housing can include a housing magnet enclosed within the housing. The shaft can be at least partially surrounded by the housing and can be rotatable within the housing. The shaft can include a shaft magnet integrated with the shaft to magnetically couple with the housing magnet to transmit a torque between the housing and the shaft and configured to uncouple from the housing magnet allowing the shaft to rotate within the housing when a threshold torque is reached.

A flexible bit holder may include a drive body having a receiving orifice formed therein, a drive body having a shank and a flexion assembly. The receiving orifice may be configured to receive a bit, and the shank may be configured to interface with a driver to receive rotational energy from the driver. The flexion assembly may be disposed between at least a portion of the drive body and the driven body to operably couple the drive body and driven body. The flexion assembly may be configured to transfer torque applied to the driven body by the driver to the drive body. The flexion assembly may be formed of flexible material such that the drive body is rotatable relative to the driven body about a common axis of the drive body and the driven body.

A work tool includes a housing, a spindle, a motor, a power-transmitting mechanism and a restricting member. The power-transmitting mechanism includes a sun member, a ring member, a carrier member and a planetary roller. One of the sun member and the ring member is configured to move together with the spindle in the front-rear direction relative to the other of the sun member and the ring member. The power-transmitting mechanism is configured to transmit power of the motor to the spindle when the sun member and the ring member relatively move toward each other in response to rearward movement of the spindle and the planetary roller gets into frictional contact with the sun member and the ring member. The restricting member is configured to restrict the planetary roller from moving in the front-rear direction relative to the housing.

One or more techniques and/or systems are disclosed for a tool driver device that can apply counter-torque to the device while applying torque to a target component that is engaging a target base. The example device can be operated by one hand to actuate a power input component that provides the desired torque, while providing counter-torque to offset rotation of the device. A selectably engaged counter-torque component is selected to complement the target base, to operably hold it in place during use. A power input provides power to apply rotational force to drive a selectably coupled tool, which has been selected to complement the target component engaged with a target base. The counter-torque component is operably engaged with the base, which applies counter-torque to the torque provided by the target component.