An impact torque generator for a hydraulic torque wrench includes a liner, a main shaft, a first drivable blade and a second drivable blade. The liner has two sealing surfaces defined at a position of 180 degree rotational symmetry. For each of the first drivable blade and the second drivable blade, a first sealing surface of the drivable blade is configured to be in contact with one of the sealing surfaces of the liner while a second sealing surface of the drivable blade slides in contact with an inner peripheral surface of the liner so as to create a seal such that a portion of an interior of the liner is divided into a high-pressure chamber and a low-pressure chamber so as to generate impact torque on the main shaft.

A rotary power tool, such as an oil pulse driver, includes: a motor, a pinion rotated by the motor, planet gears that mesh with the pinion, an internal gear that meshes with the planet gears and a shaft that is rotationally driven by the planet gears and disposed frontward of the planet gears. The internal gear comprises an internal gear part and an internal gear retaining part for holding the internal gear part. An oil unit bearing is disposed frontward of the internal gear part, and the oil unit bearing is held at a front part of the internal gear retaining part.

A pneumatic impulse wrench includes a motor, a housing with a pressure air inlet passage, an exhaust air outlet passage, and an air flow control valve provided in the exhaust air outlet passage and including a valve element shiftable between an exhaust air flow restricting position and an exhaust air flow non-restricting position. A rigid contact member is provided to positively define the exhaust air flow restricting position of the valve element, and a bypass passage of a well-defined flow area is provided to let through a limited exhaust air flow as the valve element occupies the flow restricting position in engagement with the contact member.

A torsion-detecting pneumatic impact tool is provided. A hammering set having at least one hammering block and a rotating portion which is connected with each hammering block. A transmission shaft penetrates through each the hammering block. A torsion detecting unit includes a marking piece which has a plurality of blocks, at least two sensors which detect the marking piece and an processing unit which is electrically connected with each the sensor. The hammering set, the marking piece, and the rotating assembly rotating synchronously. When each the hammering block swing strikes the transmission shaft in a direction, the hammering set and the marking piece rotate reversely slightly because of the counterforce of swing strike. When the marking piece rotates reversely, the processing unit receives a signal of a degree of rotation of the blocks detected by the at least two sensors and computes a torsion value.

A bolt clamping force transducer for a bolt tightening operation is introduced to tighten a bolted joint by driving a torque rotating shaft in a clamping force transducer, such that a helical mechanism at one end of the torque rotating shaft generates an axial force for pressing a force sensing module and thus generates a strain value thereof. A socket is driven by the other end of the torque rotating shaft, thereby generating a clamping force under which the bolted joint of a specific specification is tightened. A parameter relation between the strain value and the clamping force is calibrated with a standard axial force gauge to facilitate calculation and control of the clamping force during the tightening process where the bolted joint fitted to any torque tool is sensed to control the precision of the clamping force being exerted on the bolted joint, thereby enhancing the quality thereof.

Provided are: an impact fastening tool which prevents a torque detecting means from missing a signal and extends service life by adopting a fixed connector that prevents the trouble of being instantaneously separated (bounced) from a rotating electrode by intermittent impacts and has a shape allowing the progression of friction to be delayed structurally; and a torque tester. Both end portions of the fixed connector are fixed, and at least two protrusion portions are formed between the both end portions. The rotating electrode is disposed between one protrusion portion and the other protrusion portion such that the rotating electrode contacts the fixed connector at two or more points or in a line form. A signal required for the torque detecting means is transmitted through the contact between the rotating electrode and the fixed connector.

A method of torque control and a torque control apparatus for a pneumatic torque tool are provided. The method includes: connecting a torque control apparatus between an air supply system and a pneumatic torque tool; under predetermined working and control conditions, driving the pneumatic torque tool at the first and second working air pressures to calibrate output torque, and to obtain maximum and minimum torque values; constructing correspondence curve between air pressure and torque value based on the first and second working air pressures and the maximum and minimum torque values obtained; entering any target torque value ranging from minimum torque value to maximum torque value of the correspondence curve to obtain a corresponding working air pressure value and drive the pneumatic torque tool; and verifying whether all working and control conditions are controlled within a predetermined range of variation to control the output torque.

A bolt clamping force sensing washer includes a sensing washer, connection line assembly, and signal processor. The sensing washer includes a body, sensing component, and bushing. The body has an axial hole that matches outer diameter of a bolt's thread. The circumferential surface of the body has a circumferential groove for receiving the sensing component which measures a deformation signal generated by the body under an axial load. Two end surfaces of the body are perpendicular to the axial hole and each have a loosening-proof structure. The bushing is made of metal or plastic or formed by plastic insulating material casting to enclose the sensing component. The signal processor has a signal amplifier, microprocessor, pairing switch, power circuit unit, signal transmission unit, memory unit, RF antenna and alert unit. The connection line assembly is disposed at the bushing to electrically connect the sensing component and signal processor.

An impact tool comprises: a casing; a rotating hammer arranged in the casing and rotatable by a motor; a rotating interface element arranged in the casing and rotatable by the hammer by a series of impacts; an output shaft rotating around a rotation axis, the output shaft having a proximal end fixed to the interface element and a distal end protruding from the casing, the distal end ending with a connecting element for removable connection to an outer mechanical adaptor; a unit of measurement arranged for obtaining torque of the output shaft by a torque sensor mounted to the output shaft, the unit of measurement comprising a fixed measuring assembly mounted integrally to the casing and a rotating measuring assembly mounted so as to rotate integrally with the rotating output shaft; the fixed measuring assembly being configured to generate a supply signal and transmit the supply signal to the rotating measuring assembly to supply electrically the rotating measuring assembly; the rotating measuring assembly being configured to detect a measuring signal indicating the torque and condition the measuring signal in order to be able to send the measuring signal to the fixed measuring assembly; in which the fixed measuring assembly and the rotating measuring assembly comprise electronic devices that execute a two-directional communication in contactless mode by magnetic coupling between the fixed measuring assembly and the rotating measuring assembly, the communication being configured to supply magnetically the torque sensor and permit transmission of the measuring signal conditioned by the rotating measuring assembly to the fixed measuring assembly.

A pneumatic tool includes, but is not limited to, an air motor cylinder defining an interior configured to receive an air motor and further defining an inlet configured to receive pressurized air to supply to the air motor; a tool handle defining a source fluid passageway fluidically coupled between the inlet and an air inlet configured to receive pressurized air, the source fluid passageway configured to direct a first portion of pressurized air received by the inlet to the inlet of the air motor cylinder; an air pressure indicator coupled to the air motor cylinder and configured to provide an indication of a dynamic air pressure of the pneumatic tool; and an indicator fluid passageway fluidically coupled between the air pressure indicator and the source fluid passageway, the indicator fluid passageway configured to divert a second portion of pressurized air received by the air inlet to the air pressure indicator.