Abstract: A pneumatic ratchet wrench includes a main body formed with a receiving chamber, a head unit, a driving unit and an air motor. The head unit defines a gas passage, and includes a ring portion and a frame portion. The ring portion includes an exit in spatial communication with the gas passage and opens toward the frame portion. The driving unit includes a driving head, and a transmission shaft mounted in the head unit. The air motor drives the transmission shaft and includes a cylinder and a rotor. The cylinder includes a venting hole allowing gas produced in the cylinder to pass through the venting hole and the gas passage and to exit from the exit to be blown toward the frame portion.

Abstract: A method for detecting deviations between an actual angular displacement in a screw joint being tightened by an impulse type power wrench and an angular displacement measured between a power wrench housing and an impulse unit of the power wrench, includes determining a first angular interval (??1) between an end point (AE) of a first delivered impulse (A) and an end point (BE) of a succeeding second delivered impulse (B), determining a second angular interval (??2) between a start point (BS) of the second delivered impulse (B) and a start point (CS) of a succeeding third delivered impulse (C), comparing (??1) with (??2) to determine a difference between the intervals, and determining that a deviation exists between the actual angular displacement in the screw joint and the angular displacement measured between the power wrench housing and the impulse unit based on the determined difference between the intervals (??1 and ??2).

Abstract: A hydraulic torque impulse generator includes a drive cylinder with a hydraulic fluid chamber, an output shaft with an impulse receiving portion connected to a radially movable seal element and intermittently dividing the hydraulic fluid chamber into high and low pressure compartments, and cam profiles which can displace the seal element from an idling position to a high pressure pulse generating position. A by-pass passage communicates fluid between the high and low pressure compartments, and a valve element movable between closed and open positions controls the fluid flow. The valve element is closed during pressure build-up in the high pressure compartment and opens when a high pressure pulse is completed, and is part of a control spindle coupled to the drive cylinder. The control spindle rotates through an angular play by inherent kinetic energy at an abrupt stop of the drive cylinder at the generation of each high pressure pulse.

Abstract: Mechanisms for reducing power output of a power tool by restricting airflow into the motor of the tool. The power regulator can be implemented in only one of the rotational directions, for example, the forward (or clockwise) direction, and can be independent of the forward/reverse mechanism to avoid a user becoming confused as to the source of tactile feedback. By limiting air input to the motor, rather than bleeding out motor output, the mechanisms prevent wasted power output. Also, the power regulation mechanism can be located near the motor to more effectively restrict airflow.

Abstract: A remote-controlled adjustable-speed screw drill for gas-drive hydraulic-motive during gas drilling is provided, including a piston speed control system, a motor assembly, a cardan shaft assembly and a transmission shaft assembly which are connected with each other from up to down in sequence. The motor assembly includes air inlets, a cam, air cylinders, pistons, a connecting rod, air outlets, liquid inlets, hydraulic cylinders, liquid check valves, a liquid storage chamber, liquid outlets, a liquid injecting chamber, a liquid injecting hole, an anti-drop cap, a rotor, a stator, and a motor assembly housing. The present invention utilizes the high-pressure gas injected by the gas drilling to drive the pistons to move back and forth at high-speed, so as to drive the incompressible liquid within the driving screw to achieve the self-circulating motion, and the screw rotor is driven to rotate by the liquid.

Abstract: A downhole actuator typically for a downhole tool such as a valve, and typically for incorporation in a string of tubulars in an oil or gas well has a central axis with radially movable counterweights on opposite sides of the axis, which move radially outward to change the activation state of the actuator. The counterweights are supported by link arms which control the movement of the counterweights in response to centrifugal force created by rotation of the body, for example, during rotary drilling operations of the string. Radial outward movement of the counterweights typically transmits axial forces between sleeves at the upper and lower ends of the counterweights, so when the counterweights move radially outward, the upper and lower sleeves approach one another, which typically triggers the actuator.

Abstract: A beverage dispensing system includes a plurality of beverage sources each containing a beverage component, and at least one flow valve connected to one or more of the beverage sources and operable to control a flow of the beverage component therefrom. The system further includes a graphical display that presents a plurality of available beverages and a gesture capture device that receives a selection gesture input to select a beverage from the plurality of available beverages. A controller is also included that adjusts the at least one flow valve based on the selection gesture input to dispense the selected beverage.

Abstract: An impact device for power transmission includes an impact unit and a hydraulic pressure adjusting unit. The impact unit has a hydraulic cylinder which is installed with a piston assembly and an output shaft therein for outputting torque through the output shaft by utilizing a hydraulic pressure provided in the hydraulic cylinder. The hydraulic pressure adjusting unit is disposed in the hydraulic cylinder and operative to adjust the hydraulic pressure of the hydraulic cylinder. Therefore, the impact device for power transmission can generate a hydraulic torque pulse, and the magnitude of the output torque can be adjusted by the hydraulic pressure adjusting unit.

Abstract: A pneumatic driven wrench comprises: a housing defining a middle channel; a cylinder defining two fluid passages; a rotor; a first valve; a second valve driven by a valve-switching member for controlling fluid communication between the middle channel and a selected one of the fluid passages; a valve-triggering unit for driving the first valve; and a locking member driven by the valve-triggering unit to move between releasing and locking positions. The locking member engages one of the valve-switching member and the second valve when at the locking position. The locking member is disengaged from the one of the valve-switching member and the second valve when at the releasing position.

Abstract: A method, system, and computer readable medium containing programming for handling fully authenticated transmission of video or other data (content) from a provider to a recipient device via an intermediary device. An inner envelope containing the content and/or security features is prepared and digitally signed using a private cryptographic key. The signed inner envelope is then included in a second, outer envelope which may also include some or all of the content. The outer envelope is also digitally signed, thereby forming a data package which may be sent from the provider to the intermediary device. If the signature of the outer envelope is authenticated at the intermediary device, then the inner envelope is sent to the recipient device which then uses the inner signature to verify its authenticity. Authenticated content may then be presented or otherwise used at the recipient device.

Abstract: A pressure protection valve is provided which provides a fluid short circuit between a fluid pressure inlet of a hydraulic tool such as a hydraulic hammer and a low pressure region when the pressure at the fluid pressure inlet exceeds a first trigger pressure equal to a predetermined permissible pressure. This prevents damage to the hydraulic tool which can arise through operation at excessive fluid flow or pressure from hydraulic fluid supplied by a carrier vehicle. The pressure protection valve may maintain fluid communication between the fluid pressure inlet and the low pressure region until the pressure at the fluid pressure inlet reduces to a pressure below a predetermined second trigger pressure which is less than the first trigger pressure, to prevent further operation of the tool until the flow of fluid to the fluid pressure inlet has been stopped by an operator.

Abstract: A pneumatic impulse wrench for tightening screw joints includes a housing with a pressure air inlet passage, an exhaust air outlet passage, a rotation motor, a hydraulic impulse generator, and is connected to a stationary programmable control unit. The impulse wrench also includes a torque indicating mechanism connected to the control unit for feeding back electric signals responsive to the output torque of the wrench, an electromagnetically activated inlet valve arranged in the air inlet passage, and an electromagnetically activated exhaust valve which controls the exhaust air flow from the motor. The exhaust valve is a proportional valve activated by a linearly operated electromagnetic actuator and arranged to continuously adapt the exhaust air flow and, hence, the motor power to the characteristics of the actual screw joint being tightened in response to feed back signals from the torque indicating mechanism and in accordance with a programmed tightening strategy.

Abstract: An arrangement in a rock drill rig 10 has an inlet valve 31 arranged upstream from a displacement compressor 32 that is used for supplying an air flow 34 to at least one flushing hole 23 in the surface of a drill bit 20. The rock drill rig 10 also has an air regulator 35 arranged to regulate the system pressure in the air flow path 34 downstream from the compressor and a detector for detecting air flow through the at least one flushing hole 23 in the surface of the drill bit. The detector has a pressure sensor 36, arranged between the air regulator 35 and the inlet valve 31, for measuring the reduced system pressure.

Abstract: A portable power tool having a housing with a rotation motor for powering a working implement, wherein sensors are provided to indicate the motor speed and the power supply, and a programmable evaluation unit is arranged to compare indicated speed and pressure values with stored limit values, and to accumulate the total operation time of the power tool and compare that with preset time limits for tool service intervals, and an optical information unit is provided on the housing to indicate whether those stored limit values have been reached.

Abstract: A relief valve assembly limits the maximum torque of a gear motor of a hydraulically driven tool. The relief valve assembly dumps flow to a return channel to return hydraulic fluid to the supply when the relief valve assembly is activated. The relief valve assembly is placed in the channel of a directional valve spool, and varies its pressure setting depending upon spool position. This is useful to vary the pressure settings of a hydraulic motor in different directions.

Abstract: A hydraulic aggregate comprises a container, a reservoir for hydraulic oil, and a pump driven by a motor arranged in the reservoir. The motor is a pneumatic motor. An electric control unit for controlling a main valve is mounted on the container. The main valve causes a reversal of the stroke direction of the hydraulic connections. The division into pneumatics and low power electronics leads to an explosion-proof embodiment of low weight and little technical complexity.

Abstract: [Problem] To present a impact torque adjusting device of a hydraulic torque wrench capable of enhancing the precision of the magnitude of the impact torque generated by the impact torque generating device of the hydraulic torque wrench, shortening the generation period of impact toques, and enhancing the durability of the impact torque generating device of the hydraulic torque wrench, when rotating in two directions, that is, in normal rotation (when tightening) and in reverse rotation (when loosening).

Abstract: An air driver device having a simple construction, being of a compact size, and having excellent durability. The air driver device is designed to shut off a supply of compressed air to an air motor, by means of a tightening torque control mechanism and a shut-off valve mechanism, in a case where the tightening torque reaches the set torque value. The air device is designed to tighten screw members at a prescribed tightening force, wherein the tightening torque control mechanism is composed of (i) a clutch unit, (ii) a driving piston on the back face of which is formed one clutch plate, so that clutch plates of the clutch unit may move by making rotational differential motions in a case where the tightening torque reaches the set torque value, (iii) a cylinder for storing this driving piston, (iv) a check valve for operating the shut-off valve mechanism, in linkage with the driving piston through an oil charged in the cylinder, and (v) a torque control member for regulating the set torque value.

Abstract: A system for preventing accidents in the operation of a monitored apparatus carried by a user has terminal in direct contact with the body of the user and provided with a circuit for continuously or periodically transmitting an authorizing user data signal through the body of the user. A signal receiver assigned on the monitored apparatus or machine has an interface in contact with the user for receiving the signal, a circuit for continuously or periodically testing the received data signal, another circuit for outputting a clearance signal that allows operation of the monitored machine or apparatus after a successful test of the received authorizing user data signal, and yet another circuit for terminating output of the clearance signal following a successful test of the authorizing user data signal when a subsequent test of the data signal fails.

Abstract: A method and system for providing an enhanced and interactive window shopping and retail information exchange with shoppers, includes acoustic sensing in connection with one or more storefront windows of a retail store, and a corresponding transparent display located within the store and visible through the storefront window, the interior of the store being visible through the transparent display. Display of information on the transparent display, and in optional combination with audio information external to the store, prompts shoppers to tap the storefront window at locations which correspond to the locations of information displayed on the transparent display. The system and method is programmed to respond to taps on the window according to the locations of the taps with incentives to enter the store and/or to redeem awards or coupons in the store.

Abstract: A pneumatic drive system (1) in which the movement of an output drive unit (7) of a pneumatic drive (2) is controlled by control valve means (25 and 26) which are connected with the working chambers (12 and 13) of the pneumatic drive (2). The control valve means (25 and 26) comprise at least one air economy setting (30) setting a choke cross section and a high power setting (29) defining a flow cross section larger than it. Actuating means (12 and 13) serve to ensure that the control valve means (25) are switched over, in a fashion dependent on the air pressure obtaining in the at least one working chamber (12 and 13) from the normally assumed air economy setting (30) into the high power setting (29), when the output drive unit (7) meets with an increased resistance to motion.

Abstract: The invention relates to a striking device (5) comprising a striking mechanism (8) which is driven by a pressure medium. Said device comprises a percussion piston (13) which can be displaced back and forth by means of a control device and a control valve which is embodied as a pressure shut-off valve (19) or as a stop valve, said control valve automatically stopping the striking mechanism if it exceeds a predetermined maximum value based on the working pressure controlling the inlet line, blocking the pressure line (3) or maintaining the control device in one of the and positions thereof. The inventive striking device also comprises a hydraulic catcher buffer which is used to brake the percussion piston when it exceeds a predetermined impact plane. According to the invention, the control valve must remain deactivated at least as long as the percussion piston is displaced on the hydraulic catcher buffer.

Abstract: The hydraulic aggregate comprises, within a container (10), a reservoir (11) for hydraulic oil. A pump (15) driven by a motor (18) is arranged in the reservoir (11). The motor (18) is a pneumatic motor. An electric control unit (30) for controlling a main valve (23) is mounted on the container (10). The main valve causes a reversal of the stroke direction of the hydraulic connections (13,14). The division into pneumatics and low power electronics leads to an explosion-proof embodiment of low weight and little technical complexity.

Abstract: The invention relates to a striking device (5) comprising a striking mechanism (8) which is driven by a pressure medium. Said device comprises a percussion piston (13) which can be displaced back and forth by means of a control device and a control valve which is embodied as a pressure shut-off valve (19) or as a stop valve, said control valve automatically stopping the striking mechanism if it exceeds a predetermined maximum value based on the working pressure controlling the inlet line, blocking the pressure line (3) or maintaining the control device in one of the end positions thereof. The inventive striking device also comprises a hydraulic catcher buffer which is used to brake the percussion piston when it exceeds a predetermined impact plane. According to the invention, the control valve must remain deactivated at least as long as the percussion piston is displaced on the hydraulic catcher buffer.

Abstract: A right-handed and reverse air channel button for a pneumatic tool includes a basic body, at least one operating member and two air intake passageways. The basic body is pivotally positioned in a positioning hole of the base of a pneumatic tool, the operating member is secured at one side of the basic body and the air intake passageways are bored in the annular wall of the basic body. When the operating member is turned to actuate the basic body to rotate for a preset angle, the air intake a passageways will respectively correspond to an air intake channel and two guide channels of the base, which communicate with the positioning hole. Thus, air can pass through the basic body and get into the base to drive the pneumatic tool to rotate clockwise or counterclockwise, able to control the air amount, easy in assembly and convenient in operation.

Abstract: A pneumatic motor having a motor chamber having an inner surface with an eccentric longitudinal axis, a motive gas fluid inlet, and at least one end wall located transversely to the longitudinal axis with an exhaust aperture located therethrough. A rotor is rotatably disposed in the motor chamber on the eccentric longitudinal axis and having a plurality of radial slots, the rotor defining a first rotational position with respect to the longitudinal axis at which the distance between the rotor and the motor chamber is a minimum. A plurality of vanes is slidably carried within the plurality of radial slots and rotationally moving between the fluid inlet and the exhaust aperture during rotation of the rotor.

Abstract: A pneumatic tool includes a housing, a driving mechanism, a rear cap, a direction controller, a speed controller, and an operating member. The housing is formed with a component chamber and an intake passageway. The driving mechanism includes an output shaft rotatable about a rotary axis. The rear cap defines a cap chamber in spatial communication with the component chamber, and has a connecting passageway that intercommunicates the cap chamber and the intake passageway. The direction controller and the speed controller are mounted in the cap chamber for rotation about the rotary axis. The operating member is coupled to the direction controller, is accessible externally of the rear cap and the housing, and is operable to drive rotation of the direction controller about the rotary axis, thereby controlling direction of rotation of the output shaft. The speed controller is operable to vary torque and speed of the output shaft.

Abstract: In a method of regulating the feed force of a drilling device having a hydrostatic bore hole motor at the end of a linkage provided with a rotary and a feed drive, the feed of the linkage is set as a function of the pressure of the drive fluid for the bore hole motor in such a way that the liquid pressure remains in a predefined range or else remains constant. If the bore hole motor is equipped with an eccentricity for directional boring, for example with an angled housing, then, in addition or else independently of the feed control, directional deviations normally resulting from the linkage torsion can be compensated for by the eccentricity or the linkage being set to a corrected path angle.

Abstract: An impact tool having a control system for turning off a motor at a preselected torque level.

Abstract: A procedure and method for eliciting expert information on process capability and thereafter manipulating the elicited information in such a manner that it can effectively be used in a process capability database that is operating in a six sigma regime. The manipulation preferably includes converting the expert elicited information from a tolerance-type metric to a short term standard deviation (or sigma) metric, whereby the result of the manipulation is used to populate directly a process capability database and, as appropriate, thereby augment, replace or modulate the data already stored therein.

Abstract: A pressure leading path in a impact type tool is branched halfway through a bypass passage for connecting a high pressure chamber H with a low pressure chamber (L). The branch includes a first fixed aperture leading to the high pressure chamber (H). The branch also includes a second fixed aperture leading to the low pressure chamber (H). The pressure leading path is connected to a primary side of a relief valve. An automatic shutoff mechanism is operated by hydraulic operating fluid relieved from the secondary side of relief valve. The automatic shutoff mechanism cuts off the air supply to the air motor driving the tool, and thus automatically shuts off the tool, when the pressure in the pressure leading path exceeds a predetermined value. The present invention permits control of pulsed torque with high precision in a simple construction.

Abstract: A process to more accurately determine torque output of power impact tools using impulse. Also disclosed are processes for controlling power impact tools, in particular a mechanical impact wrench, by determining the impulse of the tool impacts and deriving torque values therefrom. A mechanical impact wrench having an electronic control is also disclosed.

Abstract: A torque control type impact wrench includes a first storage section for storing an ideal upper limit of the pulsed torque for screwing a male screw into a female screw, as a first storage value, a second storage section for storing a driving speed at which a driving section drives a torque producing section as a second storage value, and a control section for causing the driving section to drive the torque producing section at the second storage value and stopping the driving section when the pulsed torque exceeds the first storage value, wherein the control section causes the second storage section to store a value, which is larger than the second storage value, as a new second storage value when the pulsed torque does not reach the first storage value within a given time period after the driving section starts.

Abstract: The present invention relates to an impulse wrench for use in conjunction with a fastener engaging tool and a power supply to selectively rotate threaded fasteners. The wrench comprises a housing and an impulse manifold rotatably mounted within the housing. An impulse piston is mounted inside a impulse piston receiving space for reciprocating movement and has an impulse delivering surface and a pressurizing surface. The piston and the piston receiving space are constructed and arranged such that the pressurizing surface and an outer end portion of the piston receiving space cooperate to define at least a portion of a high pressure chamber which is filled with a substantially incompressible fluid.

Abstract: A hydraulic impact tool for use in a well, such as an oil or gas well, comprising a movable hammer which is arranged to prestress a spring by means of a hydraulic piston (16) provided with a through channel (20), and in which a movable sealing body (22, 45) is arranged to enable closing of the channel (43), so that hydraulic force from fluid under pressure applied to the impact tool, may displace the piston (16) and the hammer and prestress the spring, and in which the sealing body (22) is arranged to follow the piston (16) into an end position for so to open the channel (20) for throughput, so that the hydraulic force acting on the piston (16, 41) ceases, and the prestressed spring is released and drives the hammer to strike, at the same time as the piston (16, 41) returns to initial piston, whereafter the process is repeated. The sealing body (22) is arranged to close said channel (20) when the sealing body is subjected to a predetemined frictional force from fluid flowing through the impact tool.

Abstract: A procedure is described for determining the power output of a downhole drilling motor, when the motor is inside the wellbore. The technique uses stand-pipe pressure and fluid flow rate as the main inputs. The power output of the motor is calculated by carrying out two low flow stall tests at flow rates lower than the drilling flow rate. These tests result in "off-bottom" and stall pressures at the two flow rates. Another off-bottom pressure is taken at the actual flow rate that will be used during drilling operations. From the use of the off-bottom and stall pressure measurements, a determination is made of the differential pressure across the motor and the stall pressure at the actual drilling fluid flow rate. A full power curve and a predicted operating stand-pipe pressure for optimal power generation are provided based on an experimentally verified assumption regarding the change in rotation rate of the motor versus the differential pressure across the motor power section.

Abstract: A threading attachment for internal or external threading includes a spindle head (1) which is intended to be attached to a spindle on a machine tool and also a tap holder (5) with a holder body (6) in which a tap (13) is arranged during the threading work, the spindle head (1) and the tap holder (5) being extended along a joint axle. The tap holder (5) and the holder body (6) respectively have in threading position a power transmitting connection to the spindle head (1) via driving members (15, 16 and 28, 29, respectively) and have in back out position freely rotatable in relation to the spindle head (1) and arranged to be effected by a compressed medium via a driving member (18). The driving member can be a reaction turbine or an action turbine.

Abstract: In a preferably hydraulic control for a preferably hydraulically-driven earth boring mechanism, whereby a boring rod equipped with a boring tool is fed into and out of the earth with simultaneous rotation, the feed speed of the rod is regulated automatically in dependence on the rotational movement applied to the boring rod and/or on the feed force applied to the boring rod to optimize the speed of the boring process and to prevent overload damage to the boring rod, boring tool and other parts of the boring mechanism.

Abstract: A pneumatically powered torque impulse delivering tool for screw joint tightening comprises a housing (10) with a forward impulse chamber (11) enclosing a hydraulic impulse generator (15), a motor chamber (12) disposed rearwardly of the impulse chamber (11) and including a vane type air motor (19), and air inlet and outlet passages (26, 27) located at the rear end of the housing (10). The motor cylinder (20) is provided with radial air communication openings (37a,b, 38a,b, 39a,b) and outer grooves (37c,d, 38c,d, 39c,d) forming passages for connecting the openings (37a,b, 38a,b, 39a,b) to the air inlet and outlet passages (26, 27).

Abstract: An impulse wrench comprises a pneumatic rotation motor (12), a hydraulic torque impulse generator (13) provided with an impulse magnitude responsive actuator (17), a linear movement responsive electric signal producing device (25) located at the rear end of the motor (12), a movement transferring push rod (21) extending through an axial bore (22) in the motor rotor (16) and interconnecting the actuator (17) and the signal producing device (25), an electrically activated motive air shut-off valve (31) disposed concentrically with the signal producing device (25), and an external process controlling and monitoring unit (40) connected to the signal producing device (25) and the shut-off valve (31) and arranged to compute and compare received signals with predetermined values and to initiate shut-off of the power supply (31) as a desired tightening condition is reached.

Abstract: A compressed-air screw or bolt tightener having a driving motor which drives a driving shaft for a screwing or tightening tool is disclosed. The motor is operated by compressed air and a control valve for switching the compressed-air supply to the screw or bolt tightener on or off. A pressure-regulating valve is used to regulate the kinetic energy of the screw or bolt tightener.

Abstract: This invention is intended to effect torque control of high accuracy by detecting the oil pressure at the time of the generation of a pulse which forms the basis of the generated torque for a torque wrench and using the data thus obtained the effect torque control. Oil pressure pulses generated in a pulse generating mechanism 3 by the rotation of an air motor 1 are transmitted to a hydraulic cylinder 4 by a piston 33, a rod 36 and a piston 35. In addition, a pressure sensor 5 installed in the hydraulic cylinder 34 detects the oil pressure pulses and its signal is used to switch a switching valve 7, whereupon a stopping switching valve 9 and a stopping differential pressure valve 8 are successively switched, stopping the feeding of air to the air motor 1 while cutting of the passage of electric current from a battery 61 to an electric control circuit 6.

Abstract: An air tool for setting fasteners includes a pressure selecting valve member and internal passages for air balancing this valve member with a pressure relief pilot valve for bleeding a chamber of the valve member to atmosphere responsive to increased motor operating pressure. A plurality of such pilot valves may be provided in a manually rotatable selector disc. Each pilot valve may be set to a different torque output for quick and easy tool adjustment upon registering a given pilot valve with the pressure selecting valve chamber upon manipulation of the selector disc.

Abstract: A hydro-impulse screwing device comprises a rotary drive motor, a power source for the motor, a drive shaft, a pulsating hydraulic drive connecting the motor to the shaft and a power cut-off for the motor. The load at which the power cut-off functions is adjustable. The tool has a borehole extending through the length of the shaft, a conduit for conducting hydraulic fluid from the drive to the borehole, a valve in the borehole movable from a closed position to an open position in response to hydraulic pressure corresponding to a predetermined load to allow hydraulic pressure from the drive to actuate the power cut-off, a biassing element in the borehole for biassing the valve toward a closed position against the hydraulic pressure, wherein the force of the biassing element is adjusted at the end of the drive shaft to change the load at which the power cut-off operates.

Abstract: An air tool torque control system includes a controller operative to independently control two air tools with continuous programmed adjustment of the torque shut off point for each tool after each fastener joint is made. The torque specification is measured for each fastener joint made, is verified as being within an acceptable torque range, is compared to the set point of that torque specification range to determine the variation therebetween, and is then adjusted toward the mid point by the applicable correction factor for the variation determined to continuously compensate for variations in joint rate, line pressure and/or tool output. To enhance the effectiveness of the system, fast acting solenoid valves utilizing line pressure to assist in valve closure may be included to improve shut off control.

Abstract: Disclosed is a tightening control apparatus for a torque wrench including a pressure detecting device for detecting an admission pressure supplied to a torque wrench. A pressure change detecting device determines a change in pressure detected by the pressure detecting device. A striking signal output device outputs a striking signal when the change reaches a reference value.