Abstract: A vent subassembly includes a vent body having an opening which is covered or uncovered dependent upon the location of a vent sleeve relative to the vent body. The vent subassembly can be connected below a packer, and the vent sleeve can be connected to a perforator so that movement of the vent sleeve is concurrently communicated to the perforator, such as for initiating the firing of the perforator. The vent sleeve is moved by an actuator subassembly, which is to be connected above the packer if the vent and actuator subassemblies are used with a packer. The actuator subassembly has a piston housing, a piston slidably disposed in the piston housing, and a connector string extending from the piston to the vent sleeve. The piston is responsive to a differential pressure existing between the annulus outside the actuator subassembly and an interior pressure within the actuator subassembly.

Abstract: An improved walk behind soil compactor having a double vibratory drum and an articulated frame. The compactor includes a rear drive unit having a pair of drive wheels and a forward frame is connected to the forward end of the rear drive unit by an articulated joint. The forward frame is attached through isolation mounts to a drum frame that includes a vertical support plate. A horizontal shaft is journaled with respect to the plate and a pair of drums are secured to the shaft on either side of the support plate. A power operated drive mechanism carried by the drum frame is connected through a gear drive to the shaft to drive the drums and a vibratory unit mounted on the drum frame imparts vibration to the drums. As the drums are supported solely from the central vertical support plate, the compactor is capable of compacting soil immediately adjacent to vertical walls.

Abstract: A device for controlling the spacing of the plates on a bridging arrangement for expansion joints in bridges or the like, in which device one or more plates run parallel between edge beams defining the expansion joint and are mounted on cross-members bridging the expansion joint. The plate is coupled to the two edge beams, or each plate is coupled to an edge beam and an adjacent plate or to two adjacent plates, by means of resilient members arranged to act in shear. Each resilient member is secured by one end to an edge beam or a plate and by the other end to a connector that is resilient to bending. Each connector connects the resilient members of an edge beam and a plate or of two plates to one another. All the plates are connected to one another and to the edge beams by one or more continuous control chains comprising shear springs and connectors.

Abstract: A bicycle derailleur which includes a linkage mechanism formed of a base member, an inner linkage member, an outer linkage member, and a movable member carrying a chain guide. The derailleur also includes a connecting assembly formed of a pair of connecting pins for respectively pivotably supporting one end of each of the inner and outer linkage members to the base member and a pair of connecting pins for respectively pivotably supporting the movable member to the other end of each of the inner and outer linkage members. The connecting pins are oriented obliquely with respect to a predetermined plane perpendicular to the axis of the sprocket assembly. The chain guide, responsive to deformation of the linkage mechanism, moves axially and radially of the sprocket assembly.

Abstract: A rock drill in which the depth of the recessed groove for accommodating the cutting body is made greater than the axial brazing-in depth of the cutting body whereby a largely stress-free seating of the cutting body results. In particular, for rock drills for making break-throughs, this recessed groove extended in the radial direction into lobes of a drill head can be used for locating cutting bodies in the lobes.

Abstract: A device for making measurements and interventions during fluid production or injection in a well passing through a geological formation is provided in tubing located in the well. The device has a propulsion position in the production tubing and a measuring or intervention position and comprises means supporting sealing members which are adapted on the one hand for uncovering an opening allowing fluid to flow along the tubing and an extension in said measuring or intervention position of the device and on the other for closing said opening in said propulsion position.

Abstract: A differential fill valve assembly for application in float collars or shoes in well casing. The valve assembly comprises a back pressure flapper valve disposed within a substantially tubular upper housing, and a lower housing containing an activating sleeve slidably disposed therein above a double flapper valve assembly. The activating sleeve initially extends into the upper housing to a sufficient extent to maintain the flapper valve in an open position and comprises a lower tubular sleeve surmounted by a circumferential ring of longitudinally upwardly extending collet fingers having radially inwardly extending shoulders thereon, said fingers and shoulders having elastomeric inserts extending therebetween; the activating sleeve is maintained in this position through use of shear pins, by which it is secured to a support ring associated with the lower housing.

Abstract: A self-righting roadway marker support for a flexible boundary or roadway marker has a hollow anchor sleeve sunk into a supporting surface, a mounting collar secured to said anchor sleeve, a pivot strut extending through and upward from the collar, a compressible coil spring to resiliently urge the strut into contact with the collar, and a spring stop which selectively limits the extent to which the coil spring may be compressed. An oblong, radiused or chamfered aperture formed in the collar cooperates with a spring-mounting eyebolt to prevent the strut from rotating when deflected. A tool is also disclosed for installing the marker support. The force required to deflect the support assembly is set to be less than the force that would destroy or permanently set or deform the boundary marker.

Abstract: An earth boring apparatus is disclosed having bearing members comprised of transition layer polycrystalline diamond. The transition layer polycrystalline diamond bearings include a polycrystalline diamond layer interfaced with a composite transition layer comprising a mixture of diamond crystals and precemented carbide pieces subjected to high temperature/high pressure conditions so as to form polycrystalline diamond material bonded to the precemented carbide pieces. The polycrystalline diamond layer acts as the bearing surface. The transition layer bearings are preferably supported by a cemented tungsten carbide substrate interfaced with the transition layer.

Abstract: A roller chain in which the pins are provided with at least one longitudinal groove oriented toward the bushing seams to improve the lubrication of the pin-bushing interface.

Abstract: Mowing device provided with a frame (1) and at least two cuttig elements (2-5) comprising collars (7) supporting cutters and rotatable about upwardly extending axes of rotation, which cutting elements (2-5) can be rotated in opposite directions such that during operation the facing sides of the cutting elements move in a direction opposite to the intended direction of displacement (A) of the mowing device, whilst near the rearmost part of an outermost cutting element, (2,5) there has been provided a freely rotatable swath wheel (13) for guiding the cut crop onto a window, said swath wheel (13) being arranged so that seen from above said swath wheel (13, 15) overlap at least partly said collar, whereby near the rearmost side of said outermost cutting element (2, 5) there have been provided two swath wheels (13, 15) overlapping each other when seen in the intended direction of movement of the device whereby the arrangement is so that axis of rotation (14) of the foremost swath wheel (13) includes a smaller angl

Abstract: A cutting element includes a stud having an inclined supporting surface. The supporting surface intersects a side surface of the stud to form an edge. A cutting member is bonded to the supporting surface. A reinforcing shoulder projects from the supporting surface adjacent a rear portion of the cutting member. The shoulder includes a side surface, a portion of which intersects the edge along a region of the edge whose forwardmost point is spaced rearwardly from a rearwardmost point of the cutting member. When the cutting element is positioned within a bore of a drill bit, that region of the edge is completely positioned within the bore so as to be reinforced by the bore wall.

Abstract: A rotary drill bit, for drilling wells in subsurface earth formations, and designed for rotation in a given direction, comprises a bit body having an internal passageway for drilling fluid. The bit body has an operating end face and at least one opening through that face communicating with the passageway. Cutters on the bit body form at least one elongate cutting region extending generally radially along a substantial portion of the operating end face. The cutters have cutting surfaces facing in the forward direction and generally continuous cutting edges at the outer extremity of the cutting surfaces. An elongate fence is carried on the bit body, extending generally parallel to the cutting region and spaced from the cutting region in a leading direction.

Abstract: The invention provides a tail bridge for bridging a tail end of a motor vehicle and a ramp rail. A first plate to be placed on the motor vehicle tail end is joined along a straight line at one edge to a second plate making an angle of from 12 to 20 degrees with the first plate. An intermediate plate is attached at the joint of the first and second plates and runs downwardly. A third plate is attached to the lower end of the intermediate plate and runs about parallel to the second plate at a distance corresponding to the thickness of a rail to be placed between the second and third plates. Bolt holes can be provided in the first and second plates for secure attachment to the motor vehicle tail end and the ramp rail.

Abstract: The invention relates to a tool suitable for closing a production column (100) of a well when the tool is located in a connector of enlarged diameter (101). The tool is lowered on the end of a cable (76) and includes a tilting valve member (60) which is oblong in shape and which is oriented longitudinally to pass through the corresponding oblong orifice of a valve seat (69) fixed to the connector, and is then oriented transversely in order to co-operate with said seat in order to close the production column when a traction force (F) is applied to the cable (76).

Abstract: A dock leveler that includes a pivotable bridge plate and an extension that can be moved back and forth relative to the latter and serves for reseting the bridge plate on a platform that is to be loaded or unloaded. A switch is provided that effects or permits automatic return of the dock leveler into the neutral or rest position. To ensure that return to the neutral position reliably occurs only when no platform is in the vicinity of the dock leveler, there is provided below the tip of the extension a sensing element that is movable in the direction toward the bridge plate and that can be contacted by the platform. The sensing element activates the switch except when the platform contacts the sensing element, at which time the switch is deactivated.

Abstract: A tensioner for a power transmission belt that is adapted to be operated in an endless path and a method of making the same are provided, the tensioner comprising a support unit for being fixed relative to the belt, a belt engaging unit carried by the support unit and being movable relative thereto, a mechanical spring unit operatively associated with the support unit and the belt engaging unit for urging the belt engaging unit relative to the support unit and against the belt with a force to tension the belt, and a frictional dampening unit operatively associated with the support unit and the belt engaging unit to dampen the movement of the belt engaging unit relative to the support unit in at least one direction of movement thereof. The dampening unit has a longitudinal axis and the support unit comprises a shaft having a longitudinal axis and being fixed from movement relative to the belt engaging unit.

Abstract: An easy to operate control means for shifting gears on dual shift bicycles is described. The control means is constructed so that the front and rear derailleurs of a dual shift bicycle are controlled together to shift to any selected gear from any engaged gear with a single operator action. The design permits the operator to preselect the new gear to be used while continuously pedaling in the present gear, with the actual gear change being made at the operator's discretion. The design also facilitates a rapid series of down shifts without requiring intervening gear selections.

Abstract: A blast joint comprising a series of standard length joints of production tubing is disclosed. The blast joint includes a series of cylindrical rings composed of an abrasion resistant material mounted about the tubular tubing joints forming a protective shield about the production tubing. A movable sleeve formed of cylindrical abrasion resistant rings is selectively shiftable to enclose and shield the tubing connection assemblies joining the production tubing forming the blast joint. The production tubing and abrasion resistant rings form a blast joint whose length exceeds the standard length of a single joint of production tubing.

Abstract: Apparatus and method for producing hydrocarbons from a subterranean hydrocarbon-bearing formation located beneath the floor of a body of water. A platform structure is installed on the floor over the formation and well conductors are extended down the structure and penetrate into the floor of the body of water. The conductors may include an upper vertical portion, then continually curve downwardly and outwardly through the structure above the floor in a manner maintaining a relatively smooth bore throughout the entire extent of the conductors. The conductors are extended into the floor of the body of water and wells are drilled, via the conductors, down into communication with the formation. Formation fluids are then produced from the formation via the conductors.This is a Reissue of a Patent which was the subject of a Reexamination Certificate No. B1 Re. 28,860, dated Sept. 3, 1985, Request Nos. 90/000,412, June 27, 1983 and 90/000,607, Aug. 13, 1984.