Abstract: A continuous ratchet drive for a fluid-operated wrench or the like comprises a support, a ratchet gear mounted on the support means turnably about a first pivot axis and having a plurality of ratchet teeth, a lever pivotable about a second pivot axis extending laterally from and parallel to the first pivot axis under the action of a drive, and two pawl elements pivotally connected with the lever means in pivot points which are spaced from the second pivot axis, the pawl elements being formed so that during pivoting of the lever in one direction one of the pawl elements engages with the teeth of the ratchet gear and turns the ratchet gear in one direction, while during pivoting the lever in an opposite direction the other of the pawl elements engages with the teeth of the ratchet gear and turns the ratchet gear in the same direction, each of the pawl elements including a supporting member having one end which is pivotally connected with the lever in a respective one of the pivot points and another end, and a p

Abstract: A power wrench for tightening and loosening of threaded connectors comprises fluid operated drive units including a cylinder and a piston movable in the cylinder and having an end, engaging units arranged to engage and turn a threaded connector for tightening or loosening the latter, a ratchet-pawl mechanism including a ratchet provided in the engaging units and at least two pawls arranged to engage different teeth of the ratchet for turning the ratchet in opposite directions, and units for connecting the drive units witht he pawls and including at least two levers both pivotally connected to the end of the piston and turnable about different axes and each connected with a respective one of the pawls.

Abstract: During tightening a threaded connector including for example a bolt and a nut a moment is first determined when a bolt starts to elongate, and thereafter the nut is turned only over such an angular distance with which a desired elongation of the bolt below its yield point is reached.

Abstract: A torque wrench for tightening or loosening of threaded connectors comprises a turnable engaging unit arranged to be turned and to engage threaded connector so as to tighten or loosen the latter in response to turning of the engaging unit, and a power drive unit for turning the engaging unit, the power drive unit including fluid-operated cylinder piston unit provided with a cylinder and two pistons, the pistons being movable independently of one another, so that when one piston with its smaller piston area is moved it applies a smaller pressure to the engaging unit to provide a smaller torque, while when both the pistons with a greater combined piston area are moved together they apply a greater pressure to the engaging unit to provide a greater torque.

Abstract: A fluid-operated wrench as comprising a cylinder-piston unit with a cylinder having a guide and a piston performing an active stroke in one direction and a reverse stroke in an opposite direction, an engaging member arranged to engage a threaded connector to be tightened or loosened, and formed so that its one circumferential portion engages the threaded connector while its remaining circumferential portion is open, and a reaction member arranged to abut against an adjacent object and spaced from the engaging member in the direction of the active stroke so that a reaction force during the active stroke tends to push the guide onto the engaging member and to reliably hold the latter on the threaded connector.

Abstract: A fluid operated wrench for tightening or loosening threaded connectors comprises a drive unit performing a forward and a rearward stroke, an abutment element arranged to abut against a neighboring object, and an engaging element arranged to engage and turn a threaded connector, the drive unit, the abutment element and the engaging element being connected with one another so that when the drive unit performs the forward stroke and the abutment element abuts against a neighboring object, the engaging element turns a threaded connector and at the same time a reaction force produced during the forward stroke pushes the engaging element onto the threaded connector.

Abstract: A fluid-operated wrench for tightening and loosening of threaded connectors, comprises a housing, drive unit arranged substantially in the housing, and engaging unit arranged to engage a threaded connector for tightening or loosening the same, the engaging unit being operatively connected with the drive unit so as to be turned and thereby to turn a threaded connector, the housing having a portion which extends to the engaging unit and forms an axle on which the engaging unit turns.

Abstract: A fluid operated wrench for tightening and loosening threaded connectors comprises a housing having a first axis, a drive arranged in the housing and providing a driving force in an axial direction, an engaging unit of one type provided in a polygonal opening for engaging respective threaded connector to be turned and an engaging unit of another type provided with connecting means for attaching exchangeable socket projections thereto made to engage respective threaded connector to be turned and both including an engaging element connected with the drive for turning about a second axis which is transverse to the first axis, the engaging units being mounted exchangeably so that the engaging units of one type can be removed and replaced by the engaging units of another type or vice versa, a structure in the housing for exchangeably mounting the engaging units so that the engaging unit of one type can be removed and replaced by the engaging unit of another type and vice versa, and a unit for providing reaction in

Abstract: A fluid-operated wrench has a reciprocable driving element having a driving end, and a lever arm element pivotable about an axis and having a connecting end pivotably connected with the reciprocable driving element by means of opening provided in the one end of one of the elements and having one straight side, and a sliding member having a side which slides over the straight side of the opening and being pivotably connected with the other element.

Abstract: A fluid operated wrench for tightening or loosening a threaded connector without turning the wrench around comprises fluid operated cylinder and piston unit having an axis, a support including a first support portion for supporting the cylinder and piston structure, and a second support portion extending substantially perpendicularly to the axis of the cylinder and piston structure, ratchet held by the first support portion and having a ratchet axis extending substantially perpendicular to the latter, reversable transmission intermediate the cylinder and piston unit and the ratchet structure to drive the latter in one or the opposite direction during movement of the piston, structure connected to the ratchet structure for engaging a threaded connector to be turned, whereby during turning of the threaded connector in one direction a force is created tending to turn the support structure in the opposite direction, a reaction member arranged to abut against a stationary object, and structure for adjustably attac

Abstract: A fluid-operated wrench for tightening and loosening threaded connectors comprises an action part having a turnable ratchet gear, and driving elements for turning the ratchet gear, and a reaction part arranged to counteract a reaction force created during tightening or loosening a threaded connector in one direction and tending to turn the action part in an opposite direction and including an attachment portion attachable to the action part and an abutment member arranged to abut against a stationary support during tightening or loosening of a threaded connector, wherein the attachment portion and the abutment member of the reaction part are formed as separate members engageable with one another so that the abutment member is movable relative to the attachment portion by a user.

Abstract: A fluid-operated wrench has a support, a ratchet gear turnably mounted on the support, a pair of driving pawls respectively having free ends engagable with the teeth of the ratchet gear, a drive with a driving element reciprocable along a forward and reverse stroke, a transmission between the driving element and the driving pawls and formed so that during the forward stroke one of the pawls turns the ratchet gear in one direction and during the rearward stroke the other of the pawls turns the ratchet gear in the same direction, wherein the transmission includes a driving arm, and the driving pawls are pivotally connected to the driving arm and at the same time guided in elongated curved slots formed as arcs of two circumferences which are described by two different radii with a center on the axis of the ratchet gear. The wrench has a housing accommodating the drive and also having an inner space in which the support together with the other element can be releasably insertable.

Abstract: A fluid-operated wrench, comprises at least one cylinder-piston unit having an axis and including a cylinder and a piston provided with a piston rod and movable together with the latter in axial direction, the piston rod having a free end operative for engaging one object, and a linkage connected with the cylinder and having a free end portion which is operative for engaging another object, so that when the one object is stationary while the other object a turnable threaded connector and the free end of the piston rod is brought into abutment against the one stationary object and then extended, the linkage is turned and thereby the free end portion of the linkage turns the turnable threaded connector, the linkage extending from the cylinder substantially in the axial direction.

Abstract: A fluid-operated wrench has a support, a ratchet gear mounted on the support turnably about its axis, a pair of driving pawls having free ends engageable with teeth of the ratchet gear, a driving arm which is turnable by a driving element and cooperates with the driving pawls so that during both a forward stroke and a return stroke of the driving element a respective one of the pawls turns the ratchet gear, and a guide which is formed so that the driving arm pivots about its pivot axis and which is located outside and spaced from the pivot axis of the driving arm.

Abstract: A hydraulically operated wrench which can be used either for simultaneously tightening or loosening two threaded connectors or to apply the full force of the wrench to tighten or loosen only a single threaded connector. The wrench includes a cylinder and a piston reciprocating therein, side plates connected to the cylinder, a drive lever mounted intermediate its ends on the side plates for pivoting about a first pivot axis and operatively connected at one end to the piston while being provided at the other end with a polygonal opening for engaging a polygonal member of a first threaded connector to be turned.

Abstract: A ratchet drive comprises a support in which the trunnions of a ratchet gear are mounted. A pair of transversely spaced drive plates are also mounted on the support for tilting movement about the axis of the ratchet gear between an active stroke and a return stroke so that front ends of a pair of drive pawls connected to the drive plates engage, during each active stroke of the latter, adjacent teeth of the ratchet gear to turn the latter through a predetermined angle during each active stroke.

Abstract: A ratchet drive comprises a support on which a ratchet gear is mounted turnably about a first pivot axis. A lever is mounted on the support tiltable about a second pivot axis spaced from and parallel to the first pivot axis between a forward stroke and a return stroke. A pair of drive pawls are mounted at one of the ends thereof on the lever tiltable about axes located spaced from and respectively to opposite sides of the second pivot axis and engaging with the other end thereof the ratchet gear, so that when the lever is moved along its forward stroke, one of the drive pawls will engage a tooth of the ratchet gear to turn the latter in one direction while the other pawl moves rearwardly over a tooth and so that during the return stroke the other pawl engages a tooth of the ratchet gear to turn the latter in the same direction while the one pawl moves rearwardly over a tooth.

Abstract: A hydraulically operated wrench for simultaneously tightening or loosening two threaded connectors comprises a drive unit including a cylinder and a piston reciprocatable therein and having a piston rod and a pair of transversely spaced side plates preferably releasably connected to the cylinder and projecting to one side of the latter. A plurality of differently constructed drive levers are provided to be selectively pivotally and releasably connected intermediate its ends to the side plates for pivoting about a first pivot axis and having each at one end a polygonal opening for engaging the polygonal member of a first threaded connector to be turned, whereas the opposite end of the respective drive lever is engaged by the piston rod to be tiltable about the first pivot axis at least during the forward stroke of the piston.

Abstract: A hydraulic wrench for simultaneous tightening or loosening of at least two polygonal members of threaded connectors, comprising a piston reciprocable in a cylinder, a connecting member projecting to one side of the cylinder, a lever tiltably mounted intermediate its ends on the connecting member, pivotally connected at one end to the outer end of a piston rod fixed to the piston for reciprocation therewith, a ratchet gear mounted turnable about its axis in the region of the other end of the lever and provided with a coaxial polygonal opening therethrough for engaging the polygonal head of a first threaded connector to be turned, a ratchet pawl tiltably mounted on the lever and engaging the teeth of the ratchet gear, the connecting member being provided with a plurality of transversely spaced bores therethrough, and at least one link tiltably connected at one end to a selected one of the plurality of bores, a second ratchet gear turnably mounted in the region of the other end of the link and provided with a c

Abstract: A continuous ratchet drive, especially for use in a wrench for tightening or loosening a threaded connector, mainly comprises a support on which a ratchet gear is mounted for rotation about its axis.