Abstract: An extension adapter includes a body, a collar, and a gasket. The body includes a front portion, a rear portion, and a flange separating the front portion from the rear portion. The front portion has a larger diameter than the rear portion. The body also includes an inner surface that defines a bore configured to receive a tool bit. The collar is moveable along the rear portion of the body between an unlocked position in which the tool bit is removable from the bore and a locked position in which the tool bit is secured to the body. The gasket is coupled to the rear portion of the body and abutting the flange. The gasket is compressed between the flange and the collar when the collar is in the locked position to block dust and debris from entering the bore.

Abstract: A hand-held power tool includes a tool receiver with a tubular tool holder and an assigned locking device. The assigned locking device includes a locking element configured to lock an insert tool in the tubular tool holder, a pressure sleeve that is spring-loaded via an assigned spring element, and a stop sleeve, the spring-loaded pressure sleeve configured to press the locking element in a locking position against the stop sleeve. The tubular tool holder includes at least one recess in which the locking element in the locking position is located, at least portionally. The stop sleeve has, on its inner circumference, at least one contact surface that is matched to an outer contour of the locking element such that a first surface contact between the at least one contact surface and the locking element is established in the locking position.

Abstract: This disclosure includes various embodiments of couplers for coupling intraosseous (IO) devices and drivers, and various embodiments of drivers and kits.

Abstract: A hand-held power tool includes a tool receiver that includes a tubular tool holder configured to lock an insert tool therein by an assigned locking device via at least one locking element. The locking device includes a pressure sleeve that is spring-loaded via an assigned spring element, and a stop sleeve, the stop sleeve having a contact surface on its inner circumference, and the spring-loaded pressure sleeve pressing the at least one locking element in a locking position against the contact surface. The tubular tool holder has at least one recess in which the at least one locking element in the locking position is located, at least portionally, the at least one recess having a ramp-type guideway. The at least one locking element is displaceable along the ramp-type guideway from the locking position to an unlocking position.

Abstract: A fastener driving tool and an adapter for a fastener driving tool are described herein for permitting accurate placement of fasteners with respect to an edge of a board (e.g., a top edge of a siding board). The adapter may include an adapter body having a central opening for receiving a head of a fastener driving tool and two or more pins positioned in the adapter body. At least two of the pins are positioned in the adapter body such that, when the central opening receives the head, the pins are equidistant from a center of a barrel through which the fastener driving tool drives fasteners.

Abstract: A driving tool includes a driver configured to linearly move forward along a driving line to thereby strike and drive a fastener into a workpiece. The driver includes a striking member, a support member, and an engagement member engaged with the striking member and the support member and configured to restrict movement of the striking member relative to the support member in a front-rear direction. The support member includes a support surface supporting a portion of the striking member, at least one receiving surface configured to receive a reaction force to the striking member caused by driving of the fastener, and restricting parts spaced apart from each other in the front-rear direction, located at an opposite side of the striking member from the support surface in a crossing direction crossing the support surface, and configured to restrict movement of the striking member in a direction away from the support surface.

Abstract: A hand-held power tool includes a housing in which a drive motor and a transmission that is configured to be driven by the drive motor so as to drive an output shaft are arranged. The hand-held power tool also includes a mode-setting device that has at least one rotatable actuation element configured to set an operating mode, a torque-adjusting element configured to adjust a torque, and a gear changing element configured to change gears of the transmission. The torque adjusting element and the gear changing element are releasably coupled together during a gear changing process.

Abstract: A tool bit holder includes an inner sleeve in which a longitudinal bore is defined in which a tool bit is receivable and a detent is engageable with the tool bit for locking the tool bit within the longitudinal bore. An outer sleeve surrounds the inner sleeve and is movable relative to the inner sleeve between a locking position, in which the detent is engaged with the tool bit for locking the tool bit within the longitudinal bore, and a release position, in which the detent may be disengaged from the tool bit to permit removal of the tool bit from the longitudinal bore. A spring is positioned between the inner sleeve and the outer sleeve. The spring biases the outer sleeve toward the locking position.

Abstract: An impact driver screw driving device with depth adjustment has a floating sleeve that surrounds a screw driving mechanism. A floating sleeve spring provides a constant bias between a top of the floating sleeve and a top of the screw driving mechanism. A depth adjustment sleeve is threadedly connected to a lower end of the floating sleeve. The floating sleeve and the depth adjustment sleeve are free to rotate independently of the screw driving device so concussive force of the impact driver does not change a driven screw depth adjustment set by manually rotating the depth adjustment sleeve while gripping the floating sleeve.

Abstract: The present invention relates to a hydraulic percussion device and a construction apparatus having the same, the hydraulic percussion device comprising: a cylinder; a piston; a backward port connecting a front chamber of the cylinder to a hydraulic source; a forward port formed on a rear chamber of the cylinder; a forward/backward valve for controlling the forward and backward movement of the piston; a control line for moving the forward/backward valve to a forward-movement location; a long-stroke port formed between the forward port and the backward port; a short-stroke port formed between the backward port on the cylinder and the long-stroke port; a shift valve disposed between the short-stroke port and the control line; a proximity sensor for detecting a bottom dead point of the piston upon the stroke on an object; and a controller for determining a striking condition on the basis of the detected bottom dead point, and transmitting a control signal to the shift valve.

Abstract: The invention relates to a setting tool for fastening elements, comprising a driving piston that can be driven by a primary drive, and comprising a secondary drive. In order to create a lightweight, handy setting tool, the primary drive is combined with the secondary drive in a hybrid drive system for the driving piston in such a way that the driving piston can be driven by both the primary drive and the secondary drive.

Abstract: A fastener drive and release system is used with a rotational driver to drive a fastener having a washer into a workpiece. The system includes a body, a drive assembly, a tool head and a release tip. The drive assembly includes a rotating drive portion with a first engaging member and a driven portion having a second engaging member. The driven portion reciprocates between an engaged position in which the first and second engaging members engage one another and a disengaged position. The driven portion includes a drive head to engage the fastener. The tool head is disposed at an end of the body, through which the drive head extends. The release tip is disposed on the tool head and has resilient fastener head receiving and force absorbing portions. The fastener is driven into the workpiece by rotational movement imparted to the driven portion.

Abstract: A system includes: an add-on handle; and a hand-held power tool which includes a clutch setting ring, a chuck with clamping jaws and a handle fastening arrangement which is situated axially between a section of the chuck and the clutch setting ring. In at least one operating state the add-on handle fastened to the handle fastening arrangement and the clamping jaws of the chuck are situated in at least one plane which is oriented perpendicularly to a rotation axis of the chuck.

Abstract: A handheld work apparatus has an electric motor and a voltage source for operating the motor. A manual actuation element provided on a handle of the apparatus is operated by a user and is provided for activating the motor. The actuation element is connected to a control unit which controls the energy supply from the source to the motor as a function of an operating signal of the actuation element. If the control unit is in a blocking state, the energy supply to the motor is blocked independently of the operating signal of the actuation element. After receiving a control signal, the control unit switches from the blocking state to a standby state to release an energy supply to the motor. The control signal is derived from a combination of an actuation stroke and an actuation time (?TB) of the actuation element. A method for activating the apparatus is also disclosed.

Abstract: A system and method for positioning oilfield tubulars on a drilling floor (2), having an automated tubular handling system, to permit alignment and automated make up and break out of threading operations between a stationary tubular (8) and a moving tubular (34), utilizing image information from radially offset cameras (54, 56), processing the image information to recognize the tubulars within the image and develop position information for said tubulars, combining the position information from the two camera systems to develop three dimensional information for each of the tubulars, developing instructions for the automated tubular handling system to bring the stationary and moving tubulars into vertical alignment and lowering the moving tubular into threaded contact, and engaging an automated hydraulic torque wrench to make up the threaded connection.

Abstract: A hand-held power tool having hammer-drilling, drilling and screwing modes, including a mode-setting device having an actuating element, a setting element, and a gear unit for driving an output shaft, in which the actuating and setting elements are interconnected in a rotatably fixed manner, and, in an operating mode(s), the setting element is coupled to a transmission element supported at a coupling housing assigned to the gear unit and axially displaceable at the coupling housing in a screwing position associated with the screwing mode and is axially fixed in position at the coupling housing in hammer-drilling and drilling positions of the corresponding modes; the transmission element is connected to the coupling housing in a rotatably fixed manner, a predefined operating mode being settable by rotating the setting element; the setting and transmission elements being rotatable relative to one another, the setting element embracing at least sections of the transmission element.

Abstract: A bone implant drill includes a bearing received in a sleeve. A transmission shaft includes a rod extending through the bearing and a transmission member formed on an end of the rod and received in the sleeve. The other end of the rod extends beyond the sleeve. A cutting rod includes a cutter, a coupling member received in the sleeve, and a positioning member between the cutter and the coupling member. The cutter and the coupling member are provided on two ends of the cutting rod respectively. The coupling member includes second teeth releasably engageable with first teeth on a free end of the transmission member. An elastic element is mounted in the sleeve. The elastic element includes a first end mounted around the coupling member and abutting the positioning member. The elastic element further includes a second end mounted around the transmission member and abutting the bearing.

Abstract: A handheld machine tool has a drive motor for driving a tool holder, in which a tool is able to be accommodated. In addition, a cam-action mechanism for generating a hammer function is provided, which includes a cam-action mechanism holder and a notched disk. The cam-action mechanism holder is in contact with a heat-dissipating component situated inside the housing.

Abstract: A method of steering a drill bit while drilling a wellbore can include periodically delivering an impact to the drill bit as the drill bit is rotated by a drill string. The impact may be delivered to the drill bit when an axis of the drill bit is oriented in a desired azimuthal direction relative to an axis of the drill string. Another method of steering a drill bit while drilling a wellbore may include interconnecting a bend in a drill string between an impact tool and the drill bit, and periodically delivering an impact from the impact tool to the drill bit as the drill bit is rotated by the drill string. A directional drilling system can include a drill string having a bend interconnected therein, an impact tool, and a drill bit, the bend being interconnected in the drill string between the drill bit and the impact tool.

Abstract: An apparatus for pile-driving or drilling, particularly a foundation machine, including at least one hydraulic drilling or vibration drive, which is connected with a control block in an open hydraulic circuit, by way of which drive at least one further consumer can be operated. The drive is connected with a pump by way of a first feed line and with a tank by way of a first return line. The hydraulic drive is additionally connected directly with the pump by way of a second feed line, and directly with the tank by way of a second return line.

Abstract: A hammer mechanism is described as having a snap die, a tool chuck drive shaft, and an impact generating shutoff unit, which has a blocking element, which is provided for the purpose of preventing an axial displacement of the snap die. The blocking element acts on the snap die in parallel to at least one force of the tool chuck drive shaft, at least during a drilling operation.

Abstract: A system and method of fabricating a percussion tool that includes a choke valve that is replaceable and/or maintainable without disassembly of the percussion tool. The flow tube includes inner and outer walls and at least one opening formed in the outer wall. The inner wall extends from a top end of the flow tube to a bottom end of the flow tube and defines a central channel therein. The outer wall extends from the top end towards the bottom end, surrounds a portion of the inner wall, and defines an outer channel with the inner wall. The choke is positioned at the top end over the central channel and regulate a fluid flow therethrough. A check valve is positioned in fluid communication with the choke.

Abstract: The invention relates to a percussion device having a frame, a tool mounted movable in its longitudinal direction, the percussion device containing a work chamber having a movably mounted transmission piston to compress the tool so that a longitudinal stress pulse is generated to the tool, inlet and outlet channels for conducting the pressure fluid to the percussion device and away from it and a control valve that alternately directs the pressure fluid from the inlet channel to the work chamber to act on the transmission piston and, correspondingly, discharges the pressure fluid from the percussion device. The percussion device and trans-mission piston have channels that connect the pressure fluid that acted on the transmission piston to flow during the return movement of the transmission piston through the control valve and transmission piston to the pressure fluid outlet channel and cut off the flow when the transmission piston has returned to its initial position.

Abstract: A screwing tool includes an engaging member adapted to be gripped as a handle including a first inserting member. A biasing member is received within the engaging member. A driving member includes a driving head and a guiding groove at two different ends. The guiding groove receives the first inserting member. The first inserting member interconnects the engaging member and the driving member. The biasing member is disposed between the driving member and the engaging member. A control ring receives the driving member and is selectively movable between a first position disposed at a first relative position with respect to the engaging member and in which the screwing tool becomes an impact screwdriver, and a second position disposed at a second relative position with respect to the engaging member and in which the screwing tool becomes a regular screwdriver.

Abstract: The power tool has a power transmitting mechanism. When a tool bit is not pressed against a workpiece, the power transmitting mechanism is held in a power transmission interrupted state, and when the tool bit is pressed against the workpiece, the power transmitting mechanism is held in a power transmission state in which the tool bit moves together with the driven-side member in an axial direction of the tool bit so that the driving-side member receives the torque from the driven-side member and the tool bit is driven. Tapered portions are provided between the driving-side member and the driven-side member and inclined with respect to the axial direction of the tool bit. When the driven-side member moves in the axial direction of the tool bit, frictional force is caused on the tapered portions and the torque of the driving-side member is transmitted to the driven-side member by the frictional force.

Abstract: A hydraulic hammer comprising a housing (10) with a longitudinal bore (12), cylinder sleeve (14) supported in the bore (12) a rear and cover (16) closing the bore (12), and a hammer piston (15) reciprocally powered in the cylinder sleeve (14) for delivering blows to a working implement inserted in the guide sleeve (20) mounted at the front end of the bore (12). The hydraulic hammer also comprises a distribution valve (31), for directing pressure fluid to the hammer piston (15), communicating the pressure fluid source and the cylinder sleeve (14). The valve (31) comprises both a clearance seal means (44) and a seat seal (45, 46) for improved tightness.

Abstract: A ball valve assembly for use as a control valve for controlling the flow of gas through a continuous stroke pneumatic tool. The valving element is generally spherical and non-magnetizable. The generally spherical valving element is loosely confined between two concave generally conical surfaces, which are provided on valve seat members. The concave generally conical surfaces are opposed to one another to define a valve chamber therebetween. Sufficient clearance is provided so the generally spherical valving element is free to roll and tumble as it moves in the valve chamber between the concave generally conical surfaces. This allows the ball valve assembly to be self purging of excess lubricant, dust, and the like. Wear is distributed over the entire generally spherical surface of the valving element. The loose confinement is also sufficient to provide a relatively large cross-section of gas passageway through the control valve assembly.

Abstract: The power tool has a power transmitting mechanism. When a tool bit is not pressed against a workpiece, the power transmitting mechanism is held in a power transmission interrupted state, and when the tool bit is pressed against the workpiece, the power transmitting mechanism is held in a power transmission state in which the tool bit moves together with the driven-side member in an axial direction of the tool bit so that the driving-side member receives the torque from the driven-side member and the tool bit is driven. Tapered portions are provided between the driving-side member and the driven-side member and inclined with respect to the axial direction of the tool bit. When the driven-side member moves in the axial direction of the tool bit, frictional force is caused on the tapered portions and the torque of the driving-side member is transmitted to the driven-side member by the frictional force.

Abstract: A spring clutch mechanism for transmitting a driving force of a driving part to a driven part, including a first part, a second part, and a spring disposed between the first part and the second part. The first part is connected to the driven part. The second part is connected to the driving part and is rotatable relative to the first part coaxially therewith. The first part has a first end provided with a frusto-conical portion having a first tapered surface, and the second part has a second end formed with a recess provided with a second tapered surface in contact with the first tapered surface. the first part and the second part are aligned linearly and coaxially in a state that the first end is inserted into the second end maintaining contact of the first tapered surface with the second tapered surface.

Abstract: A method and means of minimizing the effect of elastic valve recoil in impact applications, such as percussive drilling, where sliding spool valves used inside the percussive device are subject to poor positioning control due to elastic recoil effects experienced when the valve impacts a stroke limiting surface. The improved valve design reduces the reflected velocity of the valve by using either an energy damping material, or a valve assembly with internal damping built-in, to dissipate the compression stress wave produced during impact.

Abstract: A percussion apparatus driven by a pressurized incompressible fluid includes a body with two coaxial bores for slidably mounting of a tool, and separately slidably mounting a striking piston having a stepped configuration. A control device varies a stroke of the striking piston between a long and a short stroke, and is connected to the directional flow valve and to a bottom chamber of the piston cylinder. The control device includes a cylinder in which a spool is mounted. A first face of the spool is situated in a first chamber permanently subjected to a determined pressure, and a second face of the spool is situated in a second chamber connected to the braking chamber for controlling the varying of the stroke of the striking piston.

Abstract: A hydraulic rock breaking device, a protection valve and a method of operating a hydraulic rock breaking device. The rock breaking device comprises a percussion device to which pressure fluid is fed along an inlet channel. The inlet channel is provided with a protection valve arranged to monitor the volume flow of pressure fluid flowing through it. If the flow is larger than what has been preset, the protection valve closes, at least partly, the connection through it, protecting thus the percussion device against too high an input power. The protection valve comprises a throttle which generates a pressure difference the magnitude of which is dependent on the fed volume flow. Information on the pressure difference is utilized in controlling the protection valve.

Abstract: There is provided a downhole hammer including a drill bit (2) retained by short (4) and long (5) drive pins in the bore of a driver chuck (1). The chuck (1) and bit (2) shank have machined longitudinal grooves (3), every second bit shank groove being blind and connected to the adjacent open groove by a short-pin length relief. The shorter pins (4) are inserted into the visible holes formed by the alignment of the open drill bit grooves and driver chuck grooves (3). The chuck (1) is then indexed which shunts the short pins (4) sideways until the longer pins (5) are insertable. The driver chuck (1) and drill bit (2) are engaged rotationally. The bit (2) slides by the desired distance due to the shorter pins (4) being entrapped in the blind grooves. The arrangement does not require a bit shank extension to accommodate a conventional bit retainer ring.

Abstract: A method for loading coil collated fasteners into a fastening tool. The method includes providing internal access to the fastening tool by moving a door structure and a portion of a canister to load the coil collated fasteners.

Abstract: A pneumatic device control apparatus and method comprising a ported valve slidably fitted over a feed tube of the pneumatic device, and using a compliant biasing device to constrain motion of the valve to provide asymmetric timing for extended pressurization of a power chamber and reduced pressurization of a return chamber of the pneumatic device. The pneumatic device can be a pneumatic hammer drill.

Abstract: A fluid distributor cylinder is for a percussive drill assembly that includes a casing having an inner circumferential surface defining a central bore, a central axis extending through the bore, a bit movably coupled with the casing and a piston movably disposed within the casing bore. The distributor cylinder includes a generally tubular body disposeable within the casing bore and having first and second ends, a central axis extending generally between the first and second ends, an outer circumferential surface. At least a section of the outer surface is configured to engage with the inner surface of the casing so to form an interference fit between the body and the casing. The cylinder includes an exterior thread and/or a radially-extending shoulder configured to releasably engage with the casing inner surface so as to substantially prevent axial displacement of the distributor body with respect to the casing.

Abstract: A pressure joining method includes a hammer drill attachment device mountable within the chuck of a hand-held hammer drill. Using the hammer drill attachment, an operator installs flooring sheets onto a hook and loop flooring subfloor. The hammer drill attachment includes a shaft for mounting the attachment within the chuck. The hammer drill imparts vibration to the shaft when operated. An angled body member is attached to the shaft and extends downward toward a foot assembly having a foot pad means. The foot assembly vibrates when the hammer drill is actuated to cause the foot pad means to abut against the overlapping sheets of a flooring system and to press the sheets onto an underlying subfloor, thereby forming a seam between the edges of the floor sections.

Abstract: A locking mechanism of a battery pack A is provided with a hook 14 which can be locked to a mounting part B of an object equipment such as an electric tool in a state slid with respect to the mounting part, and operation parts 16 for releasing the lock which are linked to the hook 14, on a case which contains a battery. The hook 14 is urged to move upward by an elastic body in a direction of being locked to the mounting part B. The operation parts 16 are arranged in both side parts of the case within such a range that they can be grasped with a single hand from both sides of a backward end in the sliding direction of the case. When the operation parts 16 are operated from the both sides, the lock between the hook 14 and the mounting part B is released against the urge by the elastic body.

Abstract: The invention relates to a method for controlling a pressure fluid operated percussion device comprising a working chamber for pressure fluid and in the working chamber a transmission piston installed movably with respect thereto so as to enable a tool installed in the percussion device to be pressed against a material to be broken in order to generate a stress pulse, and to a percussion device. The method comprises adjusting the length of the stress pulse by adjusting the time during which pressure influences the transmission piston. The percussion device comprises an adjustment element and adjustment means for adjusting the influence time of the pressure of the pressure fluid being fed via a control valve and influencing the transmission piston.

Abstract: A bit assembly is for a percussive drill that includes a casing with an interior chamber and includes a bit connectable with the casing and having a longitudinal bore and an axis through the bore. The bore has a retainer portion with one or more generally conical inner surfaces extending circumferentially about and facing generally toward the axis. A generally cylindrical valve has a longitudinal passage with an inlet fluidly connectable with the casing chamber and an outlet fluidly connectable with the bit central bore and an axis through the passage. An engagement portion with at least one generally conical outer surface extends circumferentially about and faces generally away from the valve axis. The valve engagement portion is disposable within the bit bore retainer portion such that the valve conical outer surface is disposed within and against the bit conical inner surface to retain the valve coupled with the bit.

Abstract: Disclosed herein is a pneumatic operated hammer for rock drilling, the hammer comprising a cylindrical casing, a back head mounted at an upper portion of the casing, a check valve for opening/closing a compressed air passageway in the casing, a guide for supporting the check valve, a piston adapted to ascend and descend with compressed air in the casing, and a button bit for performing a drilling work through the striking of the piston. The piston is extended to a certain length to conform to the work condition of the pneumatic hammer to thereby prevent a water back-flow phenomenon in which underground water, etc.

Abstract: Pressure-air driven percussion device for a down-the-hole drill with a hammer-piston which is axially reciprocally movable in a hammer-piston chamber through a driving device. The hammer-piston in operation acting with a hammer-end against an upper end of a drill bit which is positioned inside a chuck. An air-cushion for reducing percussive power is arranged to be formed at the hammer-end of the hammer-piston in positions where the drill bit has been moved past a predetermined distance in the percussion direction. The drill bit is sealingly slidingly supported in a drill bit bushing, and the hammer-end of the hammer-piston is formed so that it sealingly cooperates with the drill bit bushing in the positions in order to form the air-cushion.

Abstract: A drilling and/or percussive hammer comprises a handle (10) and a hammer housing (1), which can move relative to the handle (10) and inside of which, among other things, a pneumatic spring percussive mechanism (4) is housed. The pneumatic spring of the pneumatic spring percussive mechanism (4) can be ventilated via a no-load operation duct (13, 15, 17, 26, 27) that is opened and closed by a valve (16, 17, 25). The valve (16, 17, 25) can be opened and closed according to a pressing force acting upon the handle (10). A delay device (18, 20, 21, 29, 30) controls the valve (16, 17, 25) during closing so that the valve reaches the position corresponding to the detected pressing force only with a time delay. This causes a smooth transition from the no-load operation to the percussive operation.

Abstract: A device that generally includes a multistage solenoid having at least a first stage, a second stage and an armature member that travels therebetween. The device also includes a control module connected to the multistage solenoid. The control module detects a position of the armature member relative to at least one of the first stage, the second stage and a combination thereof. The control module adjusts a magnetic field of the at least one of the first stage, the second stage and the combination thereof based on the position of the plunger armature relative thereto.

Abstract: A hammer drill includes a motor; a spindle rotatingly driven by the motor and holding an output bit; a motion conversion member for converting rotational movement of the motor to reciprocating movement; a striker reciprocatingly driven by the motion conversion member for applying an axial striking force to the output bit; a striking-motion-releasing mechanism for releasing the striking force applying action exercised by the striker; and a tightening-torque adjusting clutch for interrupting the transfer of the rotational force to the output bit by increasing a load torque.

Abstract: A percussion adapter for a positive displacement motor including a housing, a torque tube and a reciprocating percussive piston operable by application of fluid pressure thereto. The piston can be driven to create a percussive effect by rotary movement of the torque tube. The percussion adapter can have a bypass option to allow flow through the percussion adapter without operation of the piston.

Abstract: This machine includes a casing (2), a tool-holder spindle (4), a motor (6), a drive mechanism (12) having positive feed which mechanically connects the motor to the spindle and which includes a first drive member (32) for rotating the spindle, a second drive member (34) for driving the spindle in translation and which is screwed onto the spindle (4) in order to advance or return the spindle, and a clutch (36) having a return configuration which disengages the second member and the motor and an advance configuration which engages them. The clutch includes a rotary engagement member (44), a first key (48) which is movable between a position for connecting the rotary member to the motor and a position for disengaging the rotary member, and a second key (50) which is movable between a position for connecting the rotary member to the casing and a position for disengaging the rotary member.

Abstract: A percussion device having, inside a machine housing (7), a movable percussive piston (2), the movement of which being controllable through a movable valve body (5), which is arranged to, in dependence of a signal indicating the axial position of the percussive piston, alternately to a pressure source and to a low pressure connect a chamber, in which a driving surface on the piston (2) is located, whereby control channel means (10, 12; 10?, 12?) for transmitting said signal have opening means opening into a cylinder space for receiving the piston (2) for co-operation with a control edge (11,13) on the piston. Adjustment means are arranged for making possible an adjustment of which axial position of the piston said signal is transmitted. The adjustment means includes at least one axially displaceable control means (9, 9?, 9?), which contacts the piston, and which includes a portion (10, 12; 10?, 12?) of the control channel means including the opening means.

Abstract: Methods and apparatus to apply axial force to a packer in a downhole tool are described. In one described example, an apparatus to apply an axial force to an inflatable packer associated with a downhole tool includes a sleeve slidingly coupled to a body of the downhole tool and an end of the packer. An inner portion of the sleeve is sealed against the body of the downhole tool to form a chamber, and the chamber is fluidly coupled to a pump associated with the downhole tool to receive a pressurized fluid to cause the sleeve to apply an axial force to the packer.

Abstract: The invention discloses a fluid-driven impactor, a power transmission mechanism for the impactor and the use of the impactor. In the prior art, the working life of the impactor is short, since a rubber primary seal and an upper fluid-diverging lid for the fluid-driven impactor are both liable to erosion and the efficiency in transmitting power is low due to the complexity of the power transmission mechanism. In order to increase the drilling speed and/or extend the life of the impactor, the side cavity passage is formed in such a way that the inner wall of the outer pipe is isolated from the side cavity passage in a watertight manner without the use of the rubber primary seal. The loss in transmitting power is minimized by integrating the anvil of the power transmission mechanism and the lower joint.