Abstract: A hydraulic tensioner having a porous vent formed of sintered powder metal adapted to permit air to readily escape from within the tensioner while inhibiting air ingestion during cycling and limiting oil leakage. The vent is located within an aperture of the plunger near the highest point of the tensioner or at the top of the spring within the interior space of the plunger. Alternatively, the air vent may be located at the oil supply inlet before the oil enters the tensioner's fluid chamber.

Abstract: Derailleur with at least two sprockets on a sprocket unit, which is designed so that the chain can be easily shifted between a smaller sprocket and a larger sprocket. For this purpose, at least on the larger sprocket, there is a tooth space which forms a lane for the transfer of the chain between the two sprockets. By means of a side plate support ramp on the larger sprocket, a path of a chain transfer segment which is convexly bent or curved radially outward, viewed in the axial direction, is achieved, whereby the chain transfer segment is formed during the chain transfer from the smaller sprocket to the larger sprocket in the vicinity of the double tooth space.

Abstract: A chain tensioner keeps constant the tension of a chain for transmitting the rotation of an engine crankshaft to e.g. camshafts. It includes a housing having a cylinder chamber. A rod member has its rear end inserted in the cylinder chamber for pressing a chain. A tension adjusting spring biases the rod member outwardly of the housing. The chain tensioner further includes a hydraulic damper for damping a dynamic load applied to the rod member from the chain, and a thread engagement mechanism for preventing the rod member from retracting under a static load applied to the rod member.

Abstract: A pivoting member for rotatably supporting a pulley contacting a belt is pivotally fitted with a fixing shaft via a bushing while a frictional member including a slidable surface being at a right angle to the axis of the fixing shaft is forced, by an elastic force of a resilient member, into contact with a frictional surface disposed either on the pivoting member side or the fixing side, whereby a pivotal resistance is imparted to the pivoting member. The resilient member is disposed at least one place on the circumference of a circle whose center is the fixing shaft so as to inhibit the pivoting member from being inclined by a load from the belt while the frictional member is locally disposed correspondingly to the resilient member.

Abstract: A belt lifter for a vacuum cleaner includes a rotatable member attached to an extending arm for lifting a drive belt on and off of a drive shaft to respective connect and disconnect the belt. The rotatable member includes a lever arm which facilitates the rotation of the extending arm by providing a mechanical advantage. The lever arm is of sufficient length so as to permit hand gripping by an operator. The lever arm is movable between an operating position and a stowed position.

Abstract: It is envisaged in the case of a power transmission chain (1) for guiding cables, hoses and the like in a cavity surrounded by the chain links, with several chain straps (2, 3) which can be connected in detachable fashion by upper and lower cross-members, which are assembled to form two parallel strands, overlap each other and can be angled in relation to each other, and which interlock positively in the area of the mutual overlap, that each of the parallel chain strands includes inner straps (2) and outer straps (3). Each outer strap (3) overlaps two inner straps (2). The areas of the chain straps (2, 3) which are intended to overlap the adjacent chain straps (2, 3) are arranged in a common plane which roughly forms the mid-length plane of the chain straps (2, 3). (FIG.

Abstract: A compression rubber layer of a V-belt is made of an alkylated chlorosulfonated polyethylene composition in which a value of tan .delta. is 0.08 to 0.15 under conditions of a temperature of 100.degree. C. and a frequency of 10 Hz. Thus, production of a crack during the running of the belt is restricted. The alkylated chlorosulfonated polyethylene composition is composed of 0.6 to 1.2 weight % sulfur-contained alkylated chlorosulfonated polyethylene of 100 weight parts, N,N'-m-phenylene dimaleimide of 0.2 to 5.0 weight parts, dipentamethylene thiuram tetrasulfide of 0.1 to 4.0 weight parts and pentaerythrite of 0.1 to 5.0 weight parts.

Abstract: A hydromechanical torque sensor having several plenum chambers can be utilized to transmit torque between the driving and driven parts in the power train of a motor vehicle as well as to make necessary adjustments in a hydraulically adjustable transmission. To this end, the plenum chambers of the torque sensor can be connected to or sealed from each other. The torque sensor and the transmission can receive fluid from discrete sources or from a single source by way of suitable valves.

Abstract: A bicycle rear derailleur jockey pulley assembly includes a cogwheel supported on a bearing. The bearing includes an outer ring supporting the cogwheel, an inner ring disposed radially inwardly of the outer ring, and a plurality of rolling members disposed between the inner ring and the outer ring. The outer ring is capable of movement relative to the inner ring in an axial direction so that the jockey pulley may follow the axial movement of the chain after shifting.

Abstract: An insert is defined by the present invention. The insert is an elongate cylindrical body having two end faces. At the extended end, the end face supports a PDC layer which is bonded thereto by brazing or sintering and is formed of PDC material to resist impact or shock loading and to provide a long life. The PDC layer is joined to the insert body at a surface which is defined by a central elevated point, the point being relatively small in diameter or is a point, land wherein said straight radial lines extend downwardly and outwardly therefrom. The intercept of the end face with the outer surface of the insert body is an undulating sinusoidal wave form of multiple sinusoidal cycles. This provides a shock resistant insert construction.

Abstract: A drive arrangement includes an endless flexible drive element which cooperates with a pulley of variable effective diameter having two sheave members and a drive ring between the sheave members and able to run eccentrically when the sheave members move apart. The drive arrangement also includes a stabilising member for cooperating with the drive ring so as to maintain the axis of rotation of the drive ring at least substantially parallel to the axis of rotation of the sheave members.

Abstract: A hydraulic tensioner 10 includes a hollow housing 14 having formed therewith an intermediate partition wall 12, a circular hollow cylinder 16 disposed concentrically in the housing 14, and a piston rod 18 slidably received in the cylinder 16 with a small gap or clearance therebetween. The cylinder 16 and the piston rod 18 jointly define therebetween a high pressure oil chamber 20. The pressure in the high pressure oil chamber 20 counteracts the force tending to retract the piston rod 18. The piston rod 18 projects from an open end of the housing 14, and a seal 24 surrounds the piston rod 18 to seal or close the end of the housing 14. The piston rod 18 has secured thereto a rod guide 28 disposed within the low pressure oil chamber 26. A spring 36 is disposed in a compressed condition between the housing 14 and the rod guide 28 to urge the piston rod 18 in the advancing direction. The rod guide 28 has radially elongated oil holes or passages 38 formed in its surface which engages the spring 36.

Abstract: A plurality of electronically controlled downhole tools and systems for use in production wells is presented. These tools and systems include safety valve and pressure monitoring systems, remotely controlled inflation/deflation devices, remotely actuated downhole tool stop systems, remotely controlled fluid/gas control systems, remotely controlled variable choke and shut-off valve systems and a retrievable sensor side pocket mandrel.

Abstract: A hydraulic tensioner for a wrapped power transmission device designed to minimize the amount of air present in the pressure chamber. The hydraulic tensioner includes a combination pressure relief-check valve for use with a hollow piston pressure chamber containing a spring within the pressure chamber to bias the piston outward from the bore. The valve housing is designed to reduce the volume of fluid contained within the pressure chamber minimizing the amount of air which may become trapped in the pressure chamber thus improving the performance of the tensioner.

Abstract: A tubing hanger is provided with a production bore and an annulus bore spaced radially outwardly of the production bore. The annulus bore is closed by a valve member in the form of an annular disc that is rotatable by a piston provided in the tubing hanger to move between a position in which the aperture in the valve member is aligned with the annulus bore and a position in which spaced parallel upper and lower surfaces of the valve member close the annulus bore.

Abstract: A synchronous drive belt/pulley combination wherein the lateral edges of the belt overhang the pulley.

Abstract: A rotary borer has a body (10) mountable on a drill steel and one or more cutting tips (30) at a front of the body (10). Each tip (30) is tapered and is frictionally received in a corresponding tapered slot (22) in the body (10). The slot (22) has a trailing, rigid anvil surface (16), which extends almost to the extremity of the tip (30) to support the tip (30) and to locate it laterally, and a leading, resilient retaining surface (20) well shy of the extremity of the tip (30) to expose a portion of the tip. The tip (30) is readily replaceable. Release of the tip can be effected by heat or by means of taper drift (38) for which a transverse hole (37) is provided proximate a bottom of the slot (22).

Abstract: A new type of the compact freewheel body for bicycle includes a freewheel casing, a ball seat, a hub, two rows of steel balls, an adjusting ring and a clutch located in the hub. The ball ring at the top of a convention freewheel casing is moved to the bottom to become a ball seat. The distance between two rows of steel balls is increased. The freewheel body can be made more compact. Smaller gear seat may be used and thus increasing the speed ratio and improving mechanical strength of the gear set. The wobbling of the freewheel can be effectively reduced to make the freewheel running and gear shifting smoother and more reliable.

Abstract: This invention relates to dual-sided multi-ribbed power transmission belts having a plurality of longitudinally extending, transversely spaced alternating ribs and grooves with the ribs having a distance between their midpoints of a pitch P on both sides of the belt. The grooves on opposite sides of the belt are transversely offset from each by a distance of P/2.

Abstract: The proposed chain tightener is provided with a damping piston (3) in a guide bore (2). A stop ring (8) is provided between the damping piston (3) and the housing (1). The stop ring (8) cooperates with grooves (9, 17, 13) and stops (11, 10, 14) on the housing (1) and on the damping piston (3), preventing the damping piston (3) from sliding too far into the housing (1). To allow the damping piston (3) to be locked in position in the bore (2), it is proposed that the stop ring (8) should be clamped in a locking position between two contact surfaces (12, 16) on the housing (1) and damping piston (3) respectively, the contact surfaces (12, 16) being inclined in relation to the axis of the damping piston.