Abstract: The present invention provides methods and systems for an adjustment device for allowing the expeditious adjustment of drive belts that includes a frame having at least one channel, a tab extending substantially perpendicularly from the longitudinal axis of the frame, and a boss rotationally disposed on the frame. A support member is disposed adjacent the frame and includes a bore for receiving an adjustment member having a first end and a second end, and the second end of the adjustment member is disposed in close proximity to the tab of the frame.

Abstract: A tensioning device for a continuous drive element includes a housing, a tensioning piston movably guided in the housing, and a pressure chamber for hydraulic fluid formed between the housing and the tensioning piston, wherein the tensioning piston comprises a vent opening, and a vent channel between the pressure chamber and the vent opening, formed by assembling at least two vent elements, wherein in the one vent element, in the contact surface to the second vent element, separate partial areas of the vent channel are formed by molded groove sections which are connected to each other by transfer grooves molded in the second vent element in the contact surface to the first vent element, such that sections of a main portion of the cross-section of flow of the vent channel are arranged on one side, and sections are arranged on another side of a plane spanned by the contact surfaces.

Abstract: Apparatus and method for controlling an electric motor providing assistance to a bicycle rider based on measuring the mechanical power generated by the rider. The power generated by the rider is measured by measuring tension in a bicycle chain (or belt) and RPM. A chain (or belt) roller is carried at the free end of a cantilevered beam and the chain (or belt) rides over the roller. The resulting deflection of the cantilevered beam provides a measurement of chain tension. A control signal for the electric motor is generated based on a smoother version of the power generated by the rider.

Abstract: A hydraulic tensioner applies appropriate tension to an endless power transmitting belt. The hydraulic tensioner includes a plunger body, an oil supply path, a check valve, a relief valve, a pressure maintaining valve interposed in a relief path and a pressure accommodating hole. The hydraulic tensioner is configured such that a path that is branched from the oil supply path for operating the pressure maintaining valve is formed independently of a supply path to the check valve.

Abstract: Deaeration of the high pressure oil chamber of a hydraulic tensioner takes place though a helical orifice formed by opposed flanks of the threads of a threaded hole in the tensioner housing and the threads of a screw inserted into the hole. The opposed flanks are maintained in spaced relationship by a force exerted by a spring washer disposed between the head of the screw and a surface of the tensioner housing surrounding the opening of the threaded hole. The flank of the thread of the hole that forms part of the boundary of the helical orifice can have a concave curvature in order to increase the aperture of the air flow path. A groove in the surface surrounding the opening of the threaded hole prevents the washer from sealing off the flow of air. This groove is disposed with its exit end at a level above its entry end.

Abstract: The present invention relates to a timing chain system including a hydraulic pressure timing chain tensioner autonomously controlling a hydraulic pressure for maintaining tension of a timing chain to effectively operate. The system may include: a crankshaft sprocket; a camshaft sprocket controlling exhaust or intake timing of the engine; a timing chain operably connecting the crankshaft and camshaft sprockets; a chain guide for the timing chain; a chain tensioner pushing the chain guide inward; and an oil supply unit for the chain tensioner. The chain tensioner may include a housing, an operating unit case fixed to the housing, a reciprocating plunger inserted into the operating unit case, a high pressure chamber, a low pressure chamber, a supply hydraulic path supplying oil from the oil supply unit to the low pressure chamber, and a regulator controlling hydraulic pressure of the low pressure chamber.

Abstract: A method and apparatus for tensioning multi-strand endless chain conveyors ensuring equal displacement and constant alignment of each strand of endless chain. Included are a hydraulically actuated cylinder assembly, a equalizing yoke assembly, and a guide frame assembly. Hydraulic lines supplying fluid to the cylinder assembly have both check valves to prevent retraction and pressure sight indicators to signal when proper hydraulic pressure is achieved during adjustment. A common yoke and guide track is included to maintain equal displacement of chain strands while applying tensioning force. Also included is a guidance apparatus that prevents seizing of components due to foreign debris and also allows for easy removal of system for maintenance or replacement.

Abstract: There is provided a ratchet-type tensioner whose spring stopping washer for seating a ratchet biasing spring is rigidly and readily assembled to a ratchet-receiving hole so as not to fall out of the ratchet-receiving hole and which reduces flapping noise and prevents seizure of the plunger by securely and stably operating a ratchet mechanism in operating an engine. The ratchet-type tensioner 100 is arranged so that the spring stopping washer has a C-ring anchored in the rear-end area of the ratchet-receiving hole by fitting in a diameter-reduced state and by enlarging its diameter within an anchoring circumferential groove of the ratchet-receiving hole and a spring stopping piece extended from the C-ring to a ring center area to seat the ratchet biasing spring.

Abstract: A hydraulic auto-tensioner includes a sleeve having its bottom end press-fitted in a sleeve fitting hole in the bottom surface of a cylinder, a rod having its bottom end slidably fitted in the sleeve, and a return spring mounted between a spring support at the upper portion of the rod and the bottom surface of the cylinder. A pressure chamber communicates with a reservoir chamber through a passage formed between fitting surfaces of the sleeve fitting hole and the sleeve. The passage has a check valve. The rod has a valve fitting hole and a communication passage through which the valve fitting hole communicates with the reservoir chamber. The valve fitting hole has a relief valve. An orifice is formed between a valve hole formed in a valve seat of the relief valve and a valve body to prevent a sharp drop in pressure in the pressure chamber.

Abstract: A hydraulically ratcheted tensioner is provided. The tensioner includes a tensioner housing and a plunger including a groove is located partially in a piston chamber in the tensioner housing. The plunger is pressurizable by hydraulic fluid. A ratchet device includes a ratchet housing and a piston having an angled end. A spring biases the piston such that the angled end is forced against a ratchet pin that extends radially through a hole in the ratchet housing and the tensioner housing. The ratchet pin is biased against the piston by a ratchet spring. In a first, non-pressurized state, the ratchet pin engages the groove. In a second, pressurized state, the pressurized hydraulic fluid forces the piston against the spring such that the angled end disengages the ratchet pin and the ratchet spring moves the ratchet pin to a position disengaged from the groove, and the hydraulic fluid pressurizes the plunger.

Abstract: A tensioning device for an endless traction element in an engine. The tensioning device has a housing, a plunger, which can he moved in the housing, a compression spring arranged in the plunger, a nonreturn valve arranged between the plunger and the housing, a cylinder arranged in the plunger, and an engagement element. The plunger and the cylinder are connected to one another by a latching system via engagement of the engagement element, and the cylinder is connected materially to the nonreturn valve.

Abstract: An internal combustion engine includes a cam chain chamber accommodating a cam chain and a chain guide guiding the cam chain. The engine also includes a chain tensioner including a case main body, a plunger sliding in the case main body, a coil spring biasing the chain guide against the cam chain via the plunger, interlocking teeth located on a surface of the plunger, and an engaging portion engaged with the interlocking teeth and configured to inhibit the plunger from moving in a direction away from the chain guide. The engine also includes oil supply passages in an inner wall of the cylinder head and an inner wall of the cylinder body and configured to supply oil to the chain tensioner.

Abstract: An auto-tensioner includes a plunger slidably inserted in a cylinder and having a closed front end protruding from the cylinder and an open rear end which is located in the cylinder. The plunger is formed with an internal thread on its inner periphery. A screw rod having an external thread formed on its outer periphery thereof and inserted in the plunger with its external thread in threaded engagement with the internal thread of the plunger. The screw rod has a rear end protruding from the open rear end of the plunger. A seat member is mounted in the cylinder and in abutment with the rear end of the screw rod. A return spring having one end thereof supported by the screw rod biases the plunger outwardly of the cylinder to press the closed front end of the plunger against a chain or a belt. An elastic member which is compressible in the axial direction of the cylinder supports the seat member.

Abstract: A tensioning device is provided for an endless drive device, having a housing, a spring-loadable tensioning piston in a piston bore of the housing, a transport locking device, and a device to adjust the working range of the tensioning piston with a retainer element on the housing having at least one spring arm and a retainer profile arranged in the forward section of the tensioning piston in the tensioning direction. The transport locking device comprises a transport groove in the tensioning piston, the spring arm of the retainer element being engageable into the transport groove, and an unlocking element, wherein the unlocking element has at least one ramp section potentially in functional contact with the spring arm. The ramp section exerts an unlocking force on the spring arm over a travel path of the unlocking element relative to the tensioning piston, forcing said spring arm out of the transport groove.

Abstract: A tensioner has a cylindrical member having multiple locking teeth, one or multiple locking pieces having locking teeth to be engaged with the locking teeth, and a locking piece receiving part to receive the aforementioned locking pieces. A shaft member is disposed inside the cylindrical member, and either the cylindrical member or the shaft member constitutes a thrust member that can be driven forward and backward by a biasing force. A ratchet mechanism allows the thrust member to move forward by the locking pieces riding over the locking teeth of the cylindrical member as they move in a reduced-diameter direction and constrains retraction of the thrust member by the locking pieces engaging with the locking teeth of the cylindrical member as they move in an increased-diameter direction. The locking teeth are all thread-like teeth having a lead angle.

Abstract: In one aspect, the invention is directed to a belt tensioner for tensioning a belt, comprising a pivot shaft that is fixedly mountable with respect to an engine block of an engine, a tensioner arm rotatably mounted to the pivot shaft for pivoting about a tensioner arm axis in a first direction and in an opposing second direction, a pulley rotatably mounted to the tensioner arm for rotation about a pulley axis, and a tensioner spring positioned to bias the tensioner arm in the first direction, wherein the tensioner spring has a first end and a second end, wherein the first end is engaged with the tensioner arm, and a micro adjustment mechanism that is operatively connected to control the position of the second end of the tensioner spring so as to control the tension in the tensioner spring.

Abstract: A tensioning device, in particular for a highly dynamic endless drive, such as a chain drive or a belt drive for an internal combustion engine, comprises a tensioner housing, a tensioning piston displaceably arranged in the tensioner housing, a pressure chamber formed between the tensioner housing and the tensioning piston and a pressure medium inlet leading into the pressure chamber and including a non-return valve. In order to meet also new demands, in the case of which oil pumps with having a low feed pressure are used, the present device discloses that a valve body of the non-return valve is defined by a leaf spring diaphragm. The device additionally relates to a non-return valve as well as an endless drive.

Abstract: In a ratchet-type tensioner having a plunger with rack teeth formed thereon and a piston with ratchet teeth that engage the rack teeth, the ratchet teeth can be disengaged from the rack teeth by insertion of a tool through a tool insertion hole in the tensioner housing and exerting a prying action on the toothed end of the piston to move the piston away from the plunger. Alternatively if an oblique camming surface is formed on the toothed end of the piston, the ratchet teeth can be disengaged from the rack teeth by pushing the tool inward against the oblique camming surface. The piston and the hole in which it slides are shaped to prevent rotation of the piston. The ratchet teeth on the piston and the rack teeth on the plunger can be oblique to allow setback of the plunger when excessive force is exerted on the plunger.

Abstract: An engine includes an engine structure defining a plurality of cylinders. A crankshaft is rotatably mounted to the engine structure and a plurality of pistons are each disposed in a corresponding one of the plurality of cylinders and drivingly connected to the crankshaft. A drive pulley is drivingly connected to the crankshaft. An accessory is mounted to the engine structure and includes a driven pulley connected to the drive pulley by a belt. The belt has a load direction extending through an axis of rotation of the drive pulley and the driven pulley. The accessory includes a housing having two slots extending generally parallel to the load direction of the belt and each receiving a fastener therein. A tensioner bolt is located between the two slots and extends generally parallel to the load direction to apply a tension force on the housing in the load direction.

Abstract: A tensioning device for a flexible drive means, such as a chain or a belt, includes a housing, a tensioning piston movably arranged in the housing and provided with a hollow space, a pressure chamber for hydraulic fluid arranged between the housing and the tensioning piston, a vent opening arranged in the tensioning piston, and a damping means in flow communication with the vent opening and with the pressure chamber. A packing element is arranged in the hollow space of the tensioning piston and is at least a component of the damping means, such that the damping means comprises a capacity for hydraulic fluid which corresponds to at least 30% of the volume of the pressure chamber added in a 1 mm stroke of the tensioning piston in the extension direction. The device relates to a series of tensioning devices as well as a transmission and a series of transmissions.

Abstract: A tensioning device for producing tension in a chain, including a hydraulic tensioner, a tensioner arm, a lever arm and a pin member. The tensioner causes the tensioner arm to pivot at one end. The lever arm is positioned with a part toward the hydraulic tensioner. The pin member is fitted in a fixed wall and also has one end inserted in a hole in part of the lever arm.

Abstract: A system according to the principles of the present disclosure includes an engine speed module and a downshift indicator module. The engine speed module determines an engine speed when a clutch is engaged with a dual mass flywheel. The downshift indicator module generates a downshift indicator signal when the engine speed is less than a first speed, the downshift indicator signal indicating when to downshift a manual transmission.

Abstract: To provide a chain tensioner that has a simple structure, is universally usable, is capable of supplying sufficient and necessary oil when restarted after a long time after the stop of oil supply, enables reduction in entire length and size, and enables easy production and reduction in production cost. An urging unit 140 provided in an oil pressure chamber 101 to be expandable and contractible urges a plunger 120 outward from a plunger bore 111 in a tensioner body 110 of the chain tensioner 100. The plunger 120 includes a plunger body 126, a check valve 150 provided inside the body, and a reserve tube 130 that has an oil reservoir chamber 123 communicating with the oil pressure chamber 101 through an oil hole 132.

Abstract: The present disclosure relates to a chain drive assembly for a work machine, in particular for a crawler-mounted crane or a crawler excavator, having a drive crawler track, at least one displaceably supported sprocket wheel, in particular a guide wheel or idler wheel, and at least one tensioning device to tension the crawler track, wherein at least one abutment is provided which bounds the displacement of the displaceably supported sprocket wheel. The present disclosure further relates to a work machine, in particular to a crawler-mounted crane or a crawler excavator, having such a chain drive assembly.

Abstract: A chain tensioner device having a first slide surface of a main arm pivotably supported at an upper end thereof, and a second slide surface of a sub-arm pivotably supported at a lower end thereof. The first and second slide surfaces slidably abut against each other. When the main arm is biased toward a timing chain via the sub-arm by a biasing force of a plunger of a tensioner lifter, a stroke of the main arm is increased with respect to a stroke of the plunger.

Abstract: A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

Abstract: A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

Abstract: A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

Abstract: A tensioner comprising a piston slidably received within a piston bore of the housing having a plurality of grooves formed on an outer circumference, the piston forming a first pressure chamber with the piston bore. The tensioner uses a mechanism to remove a sliding pawl or expandable clip from engaging the grooves on the piston, such that the piston can move towards the housing and reduce chain load when fluid pressure is reduced in the first pressure chamber during engine shutdown, but not so much as to leave the chain uncontrolled during engine restart. The mechanism may for example be a fluid biased spool piston which engages the expandable clip or a pawl piston that engages a sliding pawl.

Abstract: In a ring-type tensioner, an expansible elastic ring disposed in a groove formed in the wall of a plunger-accommodating hole cooperates with teeth formed on the plunger to restrict axial movement of the plunger. The ring and the groove in the wall of the plunger-accommodating hole have flat radial surfaces for mutual engagement. However the ring also has oblique plunger-tooth engaging surfaces. The ring has manipulable end parts that can be locked in fixed relation to each other by a tool to secure the plunger against axial movement. The tool can also be inserted into a gap between the manipulable end parts to expand the ring and thereby release the plunger.

Abstract: A ratchet-type tensioner capable of restricting setback of a plunger includes a ratchet mechanism that allows setback of the plunger by sliding a ratchet element in a disengaging direction to disengage ratchet teeth from rack teeth when a reaction force acts on the plunger as a result of excessive chain tension. The ratchet element is slidable in a ratchet-receiving hole, and an inclination suppressing structure that prevents the ratchet element from becoming skewed in the ratchet receiving hole to an extent such that its forward end contacts one side of the hole while its rearward end contacts the opposite sides of the hole.

Abstract: A tensioning apparatus or device for a flexible driving means, particularly a drive chain for an internal combustion engine, comprises a housing, a tensioning piston movably guided in said housing and an adjusting or regulating means for gradually adjusting the working stroke of the tensioning piston. The adjusting means comprises a locking bracket and an appertaining locking profile at the tensioning piston, two arch-shaped clamping sections of said locking bracket being engageable with said locking profile, and a resilient spring portion with a torsional area combining the clamping sections in spring-resilient manner. In a preferred embodiment, the locking bracket comprises a U-shaped section with a portion angled towards the housing wall and forming the torsional area.

Abstract: To increase the pressing force on a chain as the chain undergoes greater elongation. [Resolving Means] Provision is made for: a tensioner arm 2 in which a through-hole 21a is formed at a free end 21 which can pivot about a pivoting end 20; a hydraulic tensioner 3 for causing the tensioner arm 2 to pivot about the pivoting end 20; a lever arm 4 having a boss part 40 which is rotatably supported in the through-hole 21a at the free end 21 and comprises a pin insertion hole 40a at a position which is offset from the center O of the through-hole 21a, said lever arm also having a lever part 41 which extends from the boss part 40 toward the hydraulic tensioner 3 with the tip end of a piston 3a of the hydraulic tensioner 3 in abutment against it; and a pin 5 of which one end is fitted in a fixed wall 50, and of which the other end is inserted into the pin insertion hole 40a of the boss part 40 of the lever arm 4.

Abstract: One embodiment includes a tensioner that includes a housing, a piston, and a shoe. The piston extends from the housing. The shoe is carried by the piston and has a recess. The recess receives a portion or more of the piston.

Abstract: To provide a chain tensioner that has a simple structure, is universally usable and capable of supplying sufficient and necessary oil when restarted after a long time after the stop of oil supply, and enables reduction of its length and size. Urging unit 140 provided in an oil pressure chamber 101 to be extendable and contractible urges a plunger 120 outward from a plunger bore 111 in a tensioner body 110 of the chain tensioner 100. A connection groove 122 is formed in the outer circumference of the plunger 120 to form a supply chamber 102. An oil reservoir chamber 123 is formed inside the plunger 120. A leak groove 125 is formed in the outer circumference of the plunger 120 on the side of the oil pressure chamber 101 such as to extend into the supply chamber 102.

Abstract: A tensioning device (08) for a traction-device drive having a dynamically operable tensioning element (04) which acts on a traction device (03). It is a feature of the tensioning device that it has an electromagnetic actuator (09) for operating the tensioning element (04) as a function of deflections of the traction device (03) transverse to the longitudinal extent of the traction device (03).

Abstract: A hydraulic auto-tensioner includes a cylinder with a sleeve fitting hole, and a sleeve press-fitted therein. A rod has its bottom end slidable in the sleeve. A return spring is mounted between a spring seat at an upper portion of the rod and a bottom surface of the cylinder. An oil passage, with a check valve, is formed between the fitting surfaces of the sleeve fitting hole and the sleeve and communicates the pressure chamber with the reservoir chamber. The rod has a valve fitting hole open to its bottom surface, and an oil passage communicating the valve fitting hole with the reservoir chamber. A relief valve, mounted in the valve fitting hole, includes a valve seat with a valve hole having an orifice for restricting the flow rate of oil released from the pressure chamber into the reservoir chamber through the oil passage when the relief valve opens.

Abstract: The present invention provides methods and systems for an adjustment device for allowing the expeditious adjustment of drive belts that includes a frame having at least one channel, a tab extending substantially perpendicularly from the longitudinal axis of the frame, and a boss rotationally disposed on the frame. A support member is disposed adjacent the frame and includes a bore for receiving an adjustment member having a first end and a second end, and the second end of the adjustment member is disposed in close proximity to the tab of the frame.

Abstract: A hydraulic tensioner for a traction device (1) having a pressure chamber (2) in a housing (3), into which a medium that transmits pressure can be introduced, having a feed unit (5) having a non-return valve (6) at one end (4) of the pressure chamber and having an overpressure relief device (8) at the other end (7) of the pressure chamber (2), wherein the overpressure relief device (8) includes a closure element (11), a housing body (9) and a cage (10) which is at least partly arranged within the housing body (9) and which forms a stop for the closure element (11) on the side remote from the pressure chamber, wherein the cage (10) at least partly covers an end side of the housing body (9) that is remote from the pressure chamber. The invention also relates to a traction device drive having such a tensioner for a traction device.

Abstract: A tensioning device for a continuous drive element includes a housing, a tensioning piston movably guided in the housing, and a pressure chamber for hydraulic fluid formed between the housing and the tensioning piston, wherein the tensioning piston comprises a vent opening, and a vent channel between the pressure chamber and the vent opening, formed by assembling at least two vent elements, wherein in the one vent element, in the contact surface to the second vent element, separate partial areas of the vent channel are formed by molded groove sections which are connected to each other by transfer grooves molded in the second vent element in the contact surface to the first vent element, such that sections of a main portion of the cross-section of flow of the vent channel are arranged on one side, and sections are arranged on another side of a plane spanned by the contact surfaces.

Abstract: A variable flow check valve (30) and method of manufacture thereof can include a housing (36) defining an inlet passage (38) communicating with a plurality of valve seats (32) and a ball-guiding passage (40) adjacent each valve seat (32). A plurality of balls (42) is provided; one ball (42) for each valve seat (32). Each ball (42) engages within a ball-guiding passage (40) for reciprocal movement with respect to a corresponding valve seat (32) and is normally biased toward the corresponding valve seat (32). At least two of the plurality of balls (42) have at least one different fluid flow characteristic selected from a group including a size of each ball, an allowable ball travel distance for each ball, and an amount of biasing force applied to each ball. The check valve (30) can be combined with a hydraulic tensioner (10) for an endless, flexible, power transmission member (12) for an internal combustion engine of a motor vehicle.

Abstract: In a tensioner having a housing and a plunger protruding in an advancing direction from a plunger-accommodating hole formed in the housing. The plunger has a cylindrical outer wall for sliding contact with the wall of the plunger-accommodating hole, and a tapered the rear end wall. A small clearance between the cylindrical outer wall of the plunger and the wall of the plunger-accommodating hole allows the plunger to become inclined by a small amount, which increases as the plunger advances.

Abstract: A cam drive tensioner for use with an engine includes a main body mounted to a component of the engine; a shoe movably mounted to the main body, for movement in a first direction; and two or more hydraulic chambers defined between the main body and the shoe, with the two or more hydraulic chambers being laterally spaced apart from each other in a second direction generally perpendicular to the first direction.

Abstract: In a hydraulic tensioner for maintaining tension in a traveling transmission medium in an engine, oil is delivered to an expansible chamber formed by a tensioner housing and a plunger through a reserve chamber composed of an entrance reserve chamber into which oil flows from an oil supply and a supply reserve chamber from which oil flows to the expansible chamber. A partition between the entrance and supply reserve chambers establishes a communication passage that ensures an amount of oil in the supply reserve chamber sufficient to make up the loss of oil due to leakage from the expansible chamber during a long interval while engine is inoperative, and additional leakage from the expansible chamber due to reciprocating movement of the plunger when the engine is started.

Abstract: A modular tensioner system for an engine including a modular tensioner and an application specific carrier (15). The modular tensioner includes an integral anti-rotation device (14, 24, 202), backlash adjustability, and damping element. The plunger (8, 58, 108, 158), sleeve (1, 70a, 70b, 101, 151, 270a, 270b), clip (9, 59, 109, 159), retainer (6, 106), spring (4, 54, 104, 154), and hydraulic vent device (7, 57, 107, 157, 307) may be packaged as a modular assembly with the ability to mate with various suitable carriers (15).

Abstract: In a ratchet-type tensioner having a plunger with rack teeth formed thereon and a piston with ratchet teeth that engage the rack teeth, the ratchet teeth can be disengaged from the rack teeth by insertion of a tool through a tool insertion hole in the tensioner housing and exerting a prying action on the toothed end of the piston to move the piston away from the plunger. Alternatively if an oblique camming surface is formed on the toothed end of the piston, the ratchet teeth can be disengaged from the rack teeth by pushing the tool inward against the oblique camming surface. The piston and the hole in which it slides are shaped to prevent rotation of the piston. The ratchet teeth on the piston and the rack teeth on the plunger can be oblique to allow setback of the plunger when excessive force is exerted on the plunger.

Abstract: A tensioning device for an endless drive, which has a housing, in which there is an extendable cylinder. Between the housing and the cylinder there is a pressure chamber that can be filled with a pressure fluid via a supply opening in the housing. A combination valve, which has a nonreturn valve that can be opened in the direction of the pressure chamber, a movable first shutoff element, a pressure relief valve, which can be opened counter to the aforementioned direction and a movable second shutoff element inserted in the supply opening. The first shutoff element of the nonreturn valve is arranged substantially on the pressure-chamber side of the second shutoff element.

Abstract: A traction-means tensioning device having a housing that contains aluminum as a material, into which a slide sleeve is inserted axially immovably, within which a hydraulically actuatable, axially extendable piston is supported; a pressure chamber being provided between the piston, which is made of steel, and the slide sleeve, which is made of steel, that can be filled with a hydraulic medium; a securing element engaging on the slide sleeve and the housing to fix the axial position of the slide sleeve relative to the housing, the securing element being provided with an elongate fastening portion that is configured to be fixed in position in the housing and is provided at a housing-distal end with a head that is in form-fitting contact with the slide sleeve. Also, an internal combustion engine having such a traction-means tensioning device and a traction means.

Abstract: A traction mechanism drive having a hydraulic tensioner (1) which has a housing (2) fabricated from a light-metal alloy in which a slide sleeve (4) manufactured of steel is inserted that has an axially extendable piston for deflecting a tensioning and guide unit, such as a roller or a rail, a securing element (11) being clampingly disposed between the housing and the slide sleeve to prevent the slide sleeve (4) from moving out of the housing (2). Also, an internal combustion engine having such a traction-means drive and a tensionable traction means.

Abstract: In a hydraulic tensioner, a tensioner housing is provided with an oil outflow channel communicating with a high pressure oil chamber formed by a plunger and the tensioner housing. A control valve in the oil outflow channel can be adjusted manually or automatically to optimize the damping performance of the tensioner in different engines and under different operating conditions, thereby obviating individualized machining of tensioner components to achieve optimum damping.