Abstract: The present disclosure provides a system and multicomponent apparatus for removing and installing a continuous track on a power machine or work vehicle. The system includes a support and biasing apparatus, an arcuate positioning component, a decoupling component, and interconnecting elements. The interacting apparatus and components include contact surfaces that bear against the continuous track surfaces to transfer and/or apply a series of forces, each force in the series comprising at least one of an upward, forward, or lateral force, or combinations thereof, to remove the track from or urge and install a replacement track into proper alignment and captive engagement with front idler and sprocket wheels of a continuous track vehicle wheel assembly. Removal and installation of continuous tracks is hereby achieved in a fraction of the time and with substantially less manpower than previously proposed solutions and methods.

Abstract: A track loading tool including a pump, a body including a main portion extending along a first axis, a first contact portion supported by the body and configured to engage a first rail, and a second contact portion supported by the body and configured to engage a second rail spaced apart from the first rail. The first contact portion and the second contact portion are positioned on a second axis offset from the first axis.

Abstract: A hand intended for a humanoid robot comprises a palm and at least one finger articulated to the palm, the finger comprising at least one phalanx and an articulation linking the phalanx to the palm, the phalanx extending in a main direction. According to the invention, the articulation comprises an elastic joining piece allowing several degrees of freedom. The hand comprises motorization means for a degree of freedom in rotation out of the degrees of freedom made possible by the joining piece, the motorized degree of freedom in rotation allowing a relative movement about an axis at right angles to the main direction of the phalanx. The other degrees of freedom out of the degrees of freedom made possible by the joining piece are not motorized.

Abstract: A system for pulling a subsea structure includes an adapter configured to be mounted to an upper end of a subsea pile. In addition, the system includes an interface assembly fixably coupled to the adapter. The interface assembly includes a first channel configured to receive a flexible tension member and a first chuck disposed in the first channel. The tension assembly includes a second channel configured to receive the flexible tension member and a second chuck disposed in the second channel. Each chuck is configured to pivot about a horizontal axis between an unlocked position allowing the flexible tension member to move in a first axial direction and a locked position preventing the tension member from moving in a second axial direction that is opposite the first axial direction.

Abstract: A device and a method for controlling a clamping press is provided when clamping a tension member as a function of the clamping force of a reference clamping member. The device has a hollow, cylindrical housing, wherein a piston coupled to the reference tension member is supported longitudinally displaceably along an axis. The housing and the piston encompass a pressure chamber that can be acted upon by a pressure medium for performing an axial stroke motion of the piston against the clamping force of the reference tension member by an inlet, and that can be connected by an outlet to the clamping press. The device further comprises a valve unit for controlling the application of the pressure medium to the clamping press, wherein the valve unit can be directly controlled by the stroke motion of the piston.

Abstract: An apparatuses and methods to release a chain. Apparatuses and methods include an electronic, mechanical, or electro-mechanical actuator system used to rotate a hooking arm. The actuator system includes an extendable piston. In some embodiments, the actuator system is hydraulic. In other embodiments, the actuator system is pneumatic.

Abstract: A method and system are described for tensioning structural strands 1 of a tendon in a duct. Each strand 1 is fitted with its own load cell 22, so that the individual tension values in each individual strand 1 can be measured during the tensioning of the strands 1. The load cells 22 may be removed after tensioning, or left in situ to enable ongoing monitoring of the tension in the strands 1. The load cells 22 may be calibrated simultaneously by tensioning the strands 1 to an equal tension using individual jacks 10, then normalizing the signals from each load cell 22 to the known equal tension value. A further calibration to a global strand load measurement may also be performed.

Abstract: A center hole ram can have a barrel, and a piston that is moveable relative to the barrel. The piston can define an axial hole that extends through the piston. A gripping assembly can be attached to the ram. The gripping assembly can be configured to grip a cable and pull the cable through the axial hole in response to multiple actuating strokes of the ram. Also, a bursting head can be attached to a cable. The cable can be pulled through a tunnel (such as an existing pipe) and through a piston of a ram. Pulling the cable can result in the cable pulling the bursting head through the tunnel toward the ram. Also, pulling the cable can include gripping the cable with a gripping assembly attached to the ram, and actuating the ram.

Abstract: A pole puller system comprising a base plate, a slide tube, and a slide. The system further comprises a hydraulic cylinder, a hydraulic fluid pump, and a pair of hydraulic hoses. There is also provided a means for coupling a pole to be pulled to the slide.

Abstract: Disclosed herein is a device for lifting an article comprising a housing having an inner chamber, the housing having a leading edge region in fluid communication with the inner chamber, the leading edge region being arranged to engage an access region between an article and a support surface beneath the article, an elongate tubular member having a first open end region and a second closed end region, the first open end region being directly or indirectly in fluid tight relation with the leading edge region, the elongate tubular member having a first surface in fluid communication with the inner chamber and an opposite second surface, the housing being arranged to provide a retracted position in which the elongate tubular member is held relative to the leading edge region and responsive to an operative pressure within the inner chamber to unfurl beyond the leading edge region to cause the elongate tubular member to migrate along the access region with the second surface in contact with the article and the supp

Abstract: A device and a method for controlling a clamping press is provided when clamping a tension member as a function of the clamping force of a reference clamping member. The device has a hollow, cylindrical housing, wherein a piston coupled to the reference tension member is supported longitudinally displaceably along an axis. The housing and the piston encompass a pressure chamber that can be acted upon by a pressure medium for performing an axial stroke motion of the piston against the clamping force of the reference tension member by an inlet, and that can be connected by an outlet to the clamping press. The device further comprises a valve unit for controlling the application of the pressure medium to the clamping press, wherein the valve unit can be directly controlled by the stroke motion of the piston.

Abstract: A portable winch and method of use is shown. One advantage of winches shown includes an ability to lower a boom or boom sections into limited access exit pit for winching operations such as pipe bursting. Sectional boom designs shown provide the ability to easily raise and lower a boom large distances without the need for a single long boom. Selected winch designs shown include flexible inserts between the boom and the winch frame that help resist damage from unforeseen shifting of the device during operation. Designs and methods shown also include multiple pulleys on a boom end unit. Fasteners are shown that reduce build up of debris.

Abstract: The invention relates to a floating lifting device, using two movable lifting structures (13, 14) which can be alternatively engaged with broaden support members (5, 6, 7) of a cable (4). The cable (4) is stored substantially without tension in the vessel (1), for instance on a drum or in a hawse-hole (10) in a looped configuration. Large loads (9) can be lowered and raised from the seabed at large water depths such as at 3000 m. Preferably, the cable is formed by neutral buoyancy material, such as synthetic cable.

Abstract: A carpet stretching device includes a housing, a piston unit, a carpet gripping head connected to the housing, a fluid supply unit connected to the housing, and an anchor member. The housing has front and rear ends, and a receiving space between the front and rear ends. The piston unit includes a piston member disposed in the receiving space for moving relative to the housing, a piston rod extending out of the housing through the front end, and a biasing member provided between the rear end of the housing and the piston member. The anchor member is attached to a front end of the piston rod in front of the carpet gripping head.

Abstract: A device for heaving in and paying out a chain by means of a hydraulic cylinder which by means of gripping devices engages the chain and lifts or lowers the chain a given distance while the locking device is deactivated. The structure comprises a frame provided with a lower locking device, a chain wheel guiding the chain, and an upper gripping device mounted in a bracket which is connected to the rod head of the hydraulic cylinder and the central axle of the chain wheel. The lower locking device is formed by two pawls which are pivotally mounted on separate pins. These pawls engage under a chain link and hold it securely. The upper gripping device is formed by at least one pawl which, together with a chain wheel having pockets for the chain, engages under a vertical chain link.

Abstract: A rail puller that applies tension to rail sections to reduce the gap between the ends of rail sections. The rail puller comprises a first clamp assembly and a second clamp assembly located at opposite ends of the rail puller. A clamping beam is coupled to the first clamp assembly and the second clamp assembly, and has a clamping cylinder that extends and retracts to adjust the length of the clamping beam. At least two pulling members are coupled to the first clamp assembly and the second clamp assembly, and each pulling member has a pulling cylinder that extends and retracts to adjust the length of the pulling member. The clamping cylinder extends to clamp the clamp assemblies to rail sections, and the pulling cylinders retract to draw the clamp assemblies toward one another and reduce the gap between the rail sections.

Abstract: A portable extraction tool facilitates soil stabilization applications that utilize compaction grouting. Compaction grouting involves installing grout injection casing into the ground in fixed-length sections to depths limited by soil compaction or bedrock. The casing is then removed in stages. Between stages, grout is pumped through the casing and into the soil at high pressure. The extraction tool provides the power, gripping strength, stability and operator control required to pull casings from the ground at a desired rate. Pulling power is provided by a pair of hydraulic cylinders. Gripping strength is provided by a progressive chuck mechanism that secures injection casings on upward movements of the cylinders and releases casings on downward movements, without damaging the reusable casings. Stability and strength are provided by a heavy, large-footprint base plate.

Abstract: A hydraulic cable tensioning device having a main body and tensioning yoke formed from aluminum and being capable of delivering 5,000 psi to tension a cable bearing a barrel and wedge assembly such as in a mine roof bolt or a cable truss. The body defines a pair of cavities which each receive an elongated member bearing a piston which together act as dual action hydraulic cylinders. A cable receiving bore defined in the body receives a cable gripping member to grip the cable while the tensioning yoke pushes against the barrel and wedge assembly in response to forces from the hydraulic cylinders.

Abstract: A device for heaving in chain (2,3) vertically by means of a locking device for the chain comprises one or more pawls (14,14') which engage the chain (2,3) in a combined hydraulic lifting (8) and gripping device (12) with an equivalent pawl system and an approximately 180.degree. guide device (1) for the chain. The guide device (1) and the lifting (8) and gripping device (12) are integrated in one unit in that the semicircular guide device (1) is hinged in the area which is furthest away from the incoming part of the chain, and that the gripping device consists of one or more pawls (12) which can hold the chain while it lies in its track (4,5) in the guide device (1). A hydraulic lifting cylinder (8) is hinged to the guide device (1) close to the incoming part of the chain.

Abstract: An offshore well is stabilized by at least three cables connected on one end to hydraulically powered cable tensions on the well casing at a location substantially below the surface of the body of water in which the well is located and on an opposite end to a respective anchor pile on the bottom body of water. The cables are equally tensioned by the hydraulically powered cylinder and are subsequently retained in taut condition by mechanical retainers.

Abstract: The invention is an attachment for a hydraulic rescue tool and a method of using the attachment. The attachment comprises a front face; a rear face; two opposing outer side faces; an inner bottom face, having grooves therein and being angled upwardly from the front face to the rear face; two inner side faces, the inner side faces being inclined with respect to the inner bottom face and having longitudinal grooves therein; the faces forming a unitary body having a generally flat V-shaped cross section.

Abstract: A wire fencing tensioning apparatus comprising a generally rectangular shaped open frame carriage mounted on a standard three-way hitch on the rear of a tractor. The generally rectangular shaped open frame carriage comprises a plurality of corresponding parallel members joined at ends to form corners, which members and corners define the generally rectangular shaped open frame carriage. The wire fencing tensioning apparatus has a pair of extending hydraulic cylinders. Each of the extending hydraulic cylinders has a pulley attached to the top of the extending portion or piston thereof through each of which pulley a cable is strung. The wire fencing tensioning apparatus has a hydraulic control, the hydraulic control being capable of independently controlling each of extending hydraulic cylinders. The wire fencing tensioning apparatus has a pair of pulley-cable systems by which tension is supplied to "stretch" the wire.

Abstract: The invention relates to a pneumatic wire tensioner device having a piston and a rod slidably mounted within a cylinder. The wire is attached to the rod and the cylinder is placed so as to abut a stationary structure to which the tensioned wire is to be affixed. A pressurized gas is introduced into the cylinder to move the piston away from the structure so as to tension the wire to a predetermined tension.

Abstract: A device for limiting the tension in a rope or the like comprises an anchorage plate (8) and a gripping unit (10) containing two piston and cylinder units (34), two gripping members (14) and a hydraulic control circuit which controls the gripping of the rope or the like in a manner dependent on the tension in the rope or the like. Tension P causes the gripping unit (10) and the anchorage plate (8) to separate, thus compressing fluid in chambers (46). This results in the double acting rams (30) biasing the gripping members (14) towards each other under the action of cams (26). If the tension rises above a threshold value the pressurized fluid trips pressure sensitive valve (54) allowing pressurized fluid to reverse reversing valve (55) thus temporarily relaxing the grip on the rope or the like.

Abstract: A puling device including a leverage mechanism to provide pull and lift by manipulation of a chain, and a force application mechanism to provide the leverage. The force application mechanism provides a variable torque that is at a maximum when the leverage mechanism is in a position to remove ground embedded structures, including posts. The torque diminishes as the leverage mechanism rotates and the structure is lifted. As the structure is lifted the configuration of the chain increases the rate of lift and also provides sufficient lift to remove structures deeply embedded in the ground.

Abstract: An aerial lift comprising a frame, an articulated boom including a first and second boom portions, a workman support structure mounted on the upper end of the second boom portion for pivotal movement relative thereto about a generally horizontal axis, and a mechanism for leveling the workman support structure throughout the range of movement of the first and second boom portions, the leveling mechanism including first and second sections of elongate material extending through the boom portions, a hydraulic assembly connected to the second section and including a hydraulic cylinder, a piston dividing the cylinder into first and second chambers, and a piston rod having one end fixedly connected to the piston, and a hydraulic accumulator communicating with one of the chambers.

Abstract: This is a chain tensioning system which uses a link section and a hydraulic power section. The link section is rectangular in shape and has a cross-link which is secured by a rod to a load hook external of the link. A securing nut is provided on the threaded rod inside the link frame. A hydraulic power section is used to move the cross-link away from the end of the link section and the securing nut then secures the cross-link in the tightened position. The hydraulic power section is then relaxed and removed and can be used on another appropriate link section.

Abstract: An apparatus for increasing the available hook raising and lowering distance is attached to a crane or other lifting structure having a boom and at least one lifting tackle utilizing at least one lifting line connected to a prime mover. The apparatus utilizes a support means attached to the crane boom substantially at the connection point of an existing upper tackle. A fixed, lower gripper platform is suspended from the support means and has at least one linear winch grip mounted thereon. A movable, upper gripper platform is connected to at least one lifting line associated with the lifting tackle. The upper gripper platform has at least one linear winch grip mounted thereon. The upper gripper platform is also adapted to reciprocate between the lower gripper platform and the upper tackle in response to the prime mover drawing in or paying out the lifting line. At least one extended load line for attachment to a load passes through the linear winch grips on the lower and upper gripper platforms.

Abstract: This disclosure describes a mechanical hand constructed to simulate the range of motion of a human band. The mechanical hand provides a remote manipulator device capable of reproducing all of the motions of the human wrist, hand, fingers, and thumb in a compact in-line package. The configuration of the hand allows the motion of each finger or digit to be independent of the motion the wrist and of the motion of each other digit. Also the motion of each joint of each digit is independent of the motion of each other joint on the same digit and other joints of other digits. Also, the hand allows the amount of pressure applied to an object by the digits and the resistance to motion of the joints in the hand by an external applied force on the hand to vary under the control of features inherent in the hand's construction. Further, a method for the organization of actuators for the hand, that may be fluid-activated cylinders, is described.

Abstract: An apparatus for removal of embedded utility-type poles which removes the poles quickly and efficiently from their embedded position without damage to the pole or surrounding structures. The apparatus includes at least 2 piston/cylinder members equally spaced about the pole, and a head member affixed to the top of each piston. Elongation of the piston induces rotation of the head into the pole to increase the gripping action and reduce slippage. Repeated actuation and retraction of the piston and head member will "jack" the pole from its embedded position.

Abstract: A chain tightener to tighten chains on a tractor or vehicle tire. The tightener comprises first and second spreader members, a frame consisting of a base portion and a longitudinal member extending between the base portion and the first spreader member. A longitudinal reinforcement member is mounted between the first spreader member and the base portion of the frame. The second spreader member reciprocates on the longitudinal member. A hydraulic cylinder is mounted and exerts force between the second spreader member and the base portion of the frame.

Abstract: A power hydraulic gear comprising a housing (1) which accommodates a piston (3) through which a traction guide member (7) is passed, and a mechanism for alternately engaging the piston (3) with the traction member (7). The traction member (7) is a rope sealingly passed through end faces (2, 2') of the housing (1) and through the piston (3) in which there are mounted devices (8) for engaging it with the rope, these devices engage with the rope and disengage from it upon delivery of pressurized fluid medium to one of chambers of the housing (1).

Abstract: An hydraulic load binder is disclosed for universal application, the piston rod assembly, the reservoir assembly and the pump assembly all being commonly housed. The channels to and from the pump and the piston rod chamber and the reservoir chamber are controlled by simple check valves. Two additional channels are provided for communicating the top of the piston rod chamber with the reservoir chamber. One of these additional channels includes a check valve which opens when the pressure in the piston rod chamber reaches a predetermined limit. The other additional channel is controlled by a needle valve, which is opened once a rotatable mechanical locking means is placed in locking position against the extended piston rod. Opening the needle valve depressurizes the piston rod chamber. The piston rod chamber is again pressurized to permit the mechanical lock to be released.

Abstract: An apparatus for stretching, loosening, and fixing a wire member includes a grasping member for grasping an end of the wire member, a displacing member for displacing the grasping member so as to stretch/loosen the wire member in the longitudinal direction thereof, a fixing member having a wedge receiving face, and a wedge member disposed axially between the fixing member and the grasping member. The wedge has a wedge face tapering toward the wedge receiving face of the fixing member and is divided circumferentially into a plurality of parts. A pushing member pushes the wedge member toward the wedge receiving face of the fixing member, and a holding member holds the wedge member away from the fixing member when the wire member is stretched/loosened by the displacing member.

Abstract: A hydropneumatic cable tensioner is comprised of an enclosed cylinder featuring a plurality of annular chambers. A fixed cable sheave is mounted to one end of the cylinder. A movable cable sheave is mounted to a piston rod connected to a piston which reciprocates in a piston bore chamber of the cylinder. Regulated compressed gas is connected to the outer accumulator chamber of the cylinder thereby exerting high pressure forces on oil found in the middle or high pressure oil chamber of the cylinder. Pressurized oil forces a piston to move outwardly thereby increasing the distance between the two sheaves and tensioning a cable and containment chamber within the piston rod. Restriction ports between the piston bore chamber and the containment chamber within the piston rod regulate movement of the piston and prevent uncontrolled acceleration should a cable failure occur.

Abstract: A rope pulling machine is convertible into a walking machine, and has a machine frame composed of a pulling station movable back and forth and a gripping station connected to the pulling station via a main cylinder/piston arrangement, the pulling and gripping stations each having an auxiliary cylinder/piston arrangement for a gripper, and the two grippers are linked via bearing shafts to the auxiliary cylinder/piston arrangement. The grippers have clamping jaws aligned in a rope direction and linked via bearing shafts to the pulling and gripping stations, respectively. The bearing shafts are designed as detachable shafts, making the grippers exchangeable with walkers having the same bearing points and bearing shafts and which form a walk station and a slave station. The walkers have pawls engaging a rack alternately, and running gears guided on the rack.

Abstract: Apparatus and a method is disclosed herein whereby flexible drive members such as for example conventional V-belts may be automatically prestretched and tensioned to a particular predetermined value with both a high degree of reliability and repeatablity. The apparatus comprises a sensor for continuously monitoring the actual tension on the flexible member and providing a signal to a central control unit. A force generating apparatus is also interconnected with the central control unit and operates to exert a force such as to increase or decrease the tension to which the flexible member is subjected. Wrench means may also be provided which are connected to the central control unit and actuated thereby so as to lock the movable pulley member or the like in position once the predetermined tension has been achieved on the flexible interconnecting member.

Abstract: A continuous operation linear hydraulic winch comprising a fixed frame, a first gripping assembly, a first pair of hydraulic jacks mounted between the frame and the first gripping assembly, a second gripping assembly and a second pair of hydraulic jacks mounted between the frame and the second gripping assembly, wherein the frame comprises a single bearing plate perpendicular to the jacks, the first gripping assembly is disposed on one side of the bearing plate and the second gripping assembly on the other side of the bearing plate, the first and second pairs of hydraulic jacks having one of their cylinders and piston rods connected to the bearing plate and the other of their cylinders and piston rods connected to a respective one of the first and second gripping assemblies.

Abstract: A device for tensioning and aligning a fabric includes a support member to which a plurality of tensioning segments are connected such that each of the segments in automatically lifted when a longitudinal hem of the fabric passes thereunder. The support member is provided with a guide plate at each vertical end which guide plates face each other and project into associated slots provided at the vertical ends of the segments with a play so as to allow a limited vertical movement as well as a limited horizontal movement of the segments along the guide plates. Each of the segments has a main body which is provided with a finger-like step-shaped extension so as to define a projection facing the fabric and a space which embraces the respective edge of a nap zone with a certain clearance.

Abstract: A cable mover has a generally stationary support, a tube centered on an axis and having a pair of axially opposite ends, a swivel joint carrying the tube on the support and permitting the tube to move only nonaxially thereon, and respective axially double-acting actuators carried on the tube ends. Respective double-acting grippers are carried on the actuators. The cable axially traverses the grippers, actuators, and tube. The grippers each have two sets of wedge jaws engageable with the cable, one of the sets of each gripper being effective to wedge in one axial direction with the cable and to slide in the other direction, and the other set of each gripper being oppositely effective. Each gripper also has a disabling body displaceable between end positions and through a central position with the body disabling one of the respective sets of jaws in one end position, the other set of jaws in the other end position, and neither set of jaws in the central position.

Abstract: A hydropneumatic cable tensioner is comprised of an enclosed cylinder featuring a plurality of annular chambers. A fixed cable sheave is mounted to one end of the cylinder. A movable cable sheave is mounted to a piston rod connected to a piston which reciprocates in the innermost or piston bore chamber of the cylinder. Regulated compressed gas is connected to the outer chamber of the cylinder thereby exerting high pressure forces on oil found in the middle or high pressure oil chamber of the cylinder. Pressurized oil forces a piston to move outwardly thereby increasing the distance between the two sheaves and tensioning a cable. Restriction means within the piston bore chamber regulate movement of the piston and prevent uncontrolled acceleration should a cable failure occur.

Abstract: An upstanding post is provided having a follower guidingly mounted thereon for adjustable positioning therealong. A pull lever is pivotally supported at one end from the follower for limited oscillation about a horizontal axis transverse to the lever and the lever is disposed in position generally paralleling the post. The other end of the lever is notched for engagement with successive links of a pull chain and an elongated longitudinally extendable thrust member has one end anchored relative to the follower and the other end engaged with the lever at a point spaced from its axis of oscillation for angularly displacing the lever away from the first end of the thrust member. The follower includes anchor structure disposed in the plane of swinging movement of the lever and spaced horizontally from the latter in the direction opposite to the direction in which the thrust member is operative to displace the lever.

Abstract: A traction device for causing stepwise relative displacement between the device and an elongate member in the form of a cable (6) comprises a stationary clamp (5) and a movable clamp (3) which is displaced by a cylinder and piston unit (1, 2). Both clamps (3, 5) are self-closing, but are provided with pressure-operated opening devices (8, 9). The opening devices (8, 9) are controlled by a first control valve (12) which is changed over at the stroke ends of the piston (2) by dogs (13, 14). A second control valve (15) which controls the travel direction of the piston (2) is governed by the pressure medium fed to the opening devices (8, 9).To lift a load suspended from the cable (6), the piston (2) is raised, with the movable clamp (3) closed to grip the cable and the stationary clamp (5) open. At the top of the piston stroke, the stationary clamp (5) closes, the movable clamp (3) opens, and the piston (2) falls to enable the movable clamp (3) to grip the cable (6) again at a lower position.

Abstract: Apparatus for releasing the means for gripping a pre-stress cable, to allow the cable to be detensioned. Each strand is usually maintained in the tensioned state by a cone truncated group of gripping means enveloping this strand. According to the invention each of the gripping means of a group surrounding a strand comprises towards the outside an extension which, in the active state of the gripping means, is spaced apart from this strand, all the extensions thus determining a volume of revolution terminating towards the outside by a hooking flange, while the extractor is formed by resilient parts distributed along the generatrices of a cylinder and comprises inwardly turned hooking flanges, the circumference determined by all the inner edges of the projections in the state of rest being of smaller diameter than that of the volume formed by the outer surface of the extensions of the gripping means beyond their hooking flange, when these gripping means are in the active state.

Abstract: A power tool for tensioning hose clamps of the type wherein one end portion of a strap overlies the other end portion and has a laterally extending tip which can break away or bend in response to the application of a pull sufficient to effect satisfactory tensioning of the looped central portion of the strap around a hose or the like. The tool has a barrel with an inlet receiving the one end portion so that the tip can be engaged by the shoulder of an entraining element mounted at the front end of a retractible piston rod. The tensioning element is reciprocable in and relative to a bearing which is reciprocable in the barrel by interposition of friction reducing rolling elements. When the piston rod is retracted, the shoulder of the tensioning element moves against the tip of the one end portion of the strap and exerts a pull upon the tip while moving with the bearing so that the force which is needed to bend or break the tip at least approximates the maximum force that is necessary to retract the piston rod.

Abstract: An apparatus for hauling in and letting out a flexible element such as a cable comprises a generally stationary housing defining a cable path and having a predetermined number N equal to at least three of grippers spaced in a row and shiftable along the path. These grippers can be clamped on the element in the path by respective actuators which can displace the grippers parallel to the path in a pulling direction and in an opposite letting-out direction. A controller responsive to gripper position and connected to the actuators operates them sequentially. Thus all but one of the grippers is first clamped on the element and the one gripper is unclamped from the element. Then the clamping grippers are displaced by the respective actuators with the element in one direction at a rate V.sub.w through a distance S/(N-1) while simultaneously the nonclamping gripper is displaced oppositely through a distance S along the element at a rate V.sub.r equal substantially to 2.multidot.V.sub.

Abstract: A belt tensioning tool for tensioning an endless belt that passes around a plurality of spaced apart pulleys with one of the pulleys being mounted for adjustable movement relative to the other pulleys. The belt tensioning tool has as its basic components an actuator assembly including an extensible rod member, a reaction assembly mounted to one end of the actuator assembly, and a slidable assembly mounted to the extensible rod member. The reaction assembly includes a reaction arm member which extends in a cantilevered fashion away from the extensible rod end of the actuator assembly. Similarly, the slidable assembly includes a cantilevered, slidable arm member which is mounted to the extensible rod member and is slidably movable along a track in the reaction arm member. The reaction arm member and slidable arm member include opposed adapter members having pulley engaging ends that extend in opposite directions.